Document LX50X38yQekByJjrkez7NOMd
N36947
DUP050314358
PROCEEDINGS
of
LEAD HYGIENE CONFERENCE
Held at BISMARCK HOTEL
CHICAGO, ILL. NOVEMBER 15-16, 1948
Price: $1.00
LEAD INDUSTRIES ASSOCIATION
420 LEXINGTON AVENUE NEW YORK 17, N. Y.
DUP050314359
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CONTENTS
Page Opening Address
Felix Edgar Wormser ............ ........................................ ................ 6
Solubility and Particle Size in Lead Poisoning Gordon C, Harrold, Ph.D., and Stuart F. Meek, M.D.................. Discussion, led by May R. Mayers, M.D.........................................
11 20
The Treatment of Lead Poisoning -- Past and Present David R. Johns, M.D. ...................................................... ............... Discussion, led by William C. Wilentz, M.D...................................
25 28
Preventive Medical Armor for the Lead Industry F. B-. Lanahan, M.D. ....................................................................... Discussion led by Elston L. Belknap, M.D.....................................
41 44
The Co-ordination of Industrial Medical Services Sherman S. Pinto, M.D......................................................... ...........
55
Medical Control of Lead Workers -- A State Viewpoint John E. Silson, M.D.......................................................................... Discussion, led by Warren A. Cook ...............................................
64 73
The Production Manager Looks at Industrial Health Fred M. Gillies ...................................................................................
78
The Effect of BAL on Experimental Lead Poisoning Harry Eagle, M.D. .............................................................................. 81 Discussion, led by Alsoph H. Corwin, M.D................................... 93
Air Pollution Regulations in Los Angeles County Louis C. McCabe, Ph.D...................................................................... Discussion, led by William N. Witheridge.......................................
102 107
Aluminum and Silicosis John W. Berry, M.D............................................................................ 112 Discussion, led by O. A. Sander, M.D............................................ 118
Summation of Conference Proceedings Anthony J. Lanza, M.D........................................................................ 120
Round Table Discussion ............................................................................. 125
Urinary Porphyrins in Lead Poisoning Gordon C. Harrold, Ph.D.................................................................... Discussion ...................................................
129
134
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LEAD INDUSTRIES ASSOCIATION
LEAD HYGIENE CONFERENCE NOVEMBER 15-16, 1948
MONDAY MORNING SESSION
November 15, 1948
Mr . Ro b e r t L. Zie g f el d [SecretaryTreasurer, Lead Industries Association]: Ladies and Gentlemen: I want to wel come you all here .on behalf of the Lead Industries Association. I am not going to waste any words because I know you want to get your teeth into the meat of this meeting. 1 hope that you will all enter into the discussions that are to fol low and that you will enjoy the social activities that have been arranged.
The Lead Industries Association rec ognizes health as one of the most im portant problems the industry has. We have established a Division of Health and Safety for that reason.
We hope to make that Division of the utmost service to the industry, to the medical profession and to the public. Now it is my pleasure to introduce the Chairman of this meeting who is well known to most of you, the director of
Health and Safety of the Lead Industries Association, Mr. Manfred Bowditch.
Mr . Ma n f r e d Bo w d it c h [Director of Health and Safety, Lead Industries Association]: My introductions of the speakers are going to be brief, because, obviously, you are here to hear the speakers, not to hear the introductions.
The main prelude to our Conference will be by a man who was secretarytreasurer of the Lead Industries Associ ation from 1928 to 1947, and in my present position I very frankly marvel at the time, energy and knowledge that he was able to devote to matters of health and safety, in addition to his manifold duties as secretary-treasurer.
He is now vice-president of the St. Joseph Lead Company and, very de servedly, president of the Lead Indus tries Association. Mr. Felix E. Wormser.
5
DUP050314361
OPENING ADDRESS
By FELIX EDGAR WORMSER President, Lead Industries Association Vice President, St. Joseph Lead Company, New York, N. Y.
It is my pleasant responsibility, and at the same time a rare privilege, to open
this important Lead Hygiene Confer ence. My thoughts go back to 1937 when, here in Chicago, I had the honor of pre siding over a meeting of physicians rep resenting the member companies of the Lead Industries Association and some of their friends, to exchange experiences in the detection and treatment of lead cases. I am particularly delighted that so many of you who attended that meeting are again with us today, prepared to partici pate in this constructive conference. A great amount of water has gone over the dam, or should I say, has traveled through lead pipes, since 1937. This meeting will help to bring us up to date. Not being a medical man, and not wish ing to trespass on the time of the valuable papers which are to follow, I am going to make my comments as brief as pos sible. Perhaps the best contribution I can make to the discussion is to give you a little background.
It has been my experience that many mistaken impressions about lead in hy gienic circles could have been easily avoided through better acquaintance with the lead industry. The United States is the world's greatest source of this in dispensable lead and uses large quanti ties of it each year.
It would take 200 freight trains each 100 cars long to move the lead that is consumed in our country each year. A simple calculation will show that this amounts to about one million tons. In fact, consumption today is above this rate. It is about 1,200,000 tons a year. It' may be that the thought of this volume of lead being consumed an nually in the United States is petri
fying to those alarmists about the
toxicity of our metal, as a million tons of lead, or two billion pounds, is a consumption of around 13 lb. per capita. On the contrary, my own in terpretation is that this record shows that, despite contact with lead in nearly all our daily activities, some of it remote to be sure, the absence of reported in jury on any other but an extremely modest scale, is one of the best evidences we have of the comparative safety to health under which lead can be produced and used today.
Incidentally, you might be interested to know how such a vast amount of lead is obtained in the United States. Only about one-third of it is actually mined in the country. A roughly equal share is derived from the reclamation of junk or scrap which has assumed the proportions of a very important industry in the United States and which has become, parenthetically speaking, the largest lead mine in the world. The balance of our supply is imported from Mexico, Canada, Australia and other countries.
Lead is becoming one of our most precious metals in point of price and available supply. You may have heard about this recently, and the fact that to day lead is selling close to the price of copper -- something unheard of, and which would have been considered fan tastic only a few years ago.
Some of you serve mining companies, other smelting and refining companies, and some of you attend factories where pig lead is converted into white lead, cable sheathing, storage batteries, am munition, and dozens of other important lead articles. Today, lead assumes an even more important role in industry
e
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OPENING ADDRESS
7
than ever before, because we are on the threshold of great developments in the field of atomic power where lead will be protecting the lives of human beings from the effects of dangerous secondary radiation. I like to stress this point, be cause lead is so often condemned by virtue of its admittedly toxic properties, that it is refreshing to discover that it also has great value in the medical field as a preventive material, and by that I mean to prevent damage to the body from dangerous penetration of X-rays and other harmful electrical manifesta tions. Also, that its toxic quality is used to protect our food supply as an in gredient of insecticides.
We can divide the use of lead into two groups, class (1) in the metallic form, such as pipes, sheets and alloys, and (2) in the chemical form as white lead, litharge, lead arsenate and red lead. The first or metallic class gives us little or no trouble from a health stand point, but the second may, largely be cause of the powdery nature of the product and the well-established fact that lead is ever so much more toxic when inhaled than when ingested. Al though we are concerned here largely with problems of industrial health, the question of public exposure is also part of the agenda, and I think that possibly some of my own experiences in this field may be worth while describing.
When I first became seriously inter ested in the problem of lead hygiene quite a few years ago, I was inclined to accept without much questioning many of the pronouncements that were made about lead in hygienic and medical cir cles, but it soon became apparent to me that our knowledge was not as thorough as it .should be. Thanks to the perfectly enormous amount of work that has been done in medical circles over the past 35 years in more places than I can con veniently give credit to here, I feel that,
like a good many fears that plague humanity, this one can be dissipated in the light of our growing knowledge. For example, during the war, in an effort to economize on scarce tin, all of which has to be imported into the United States, and to consume lead (which by the way becomes plentiful in wartime), I sug gested to an officer of the Food and Drug Administration that shaving cream might well be packed in lead instead of tin or aluminum collapsible tubes. He disagreed because he said, "Suppose someone shaved and cut his face? He would" be apt to contract lead poison ing." Comment is superfluous. Events subsequently made it necessary to use lead for the purpose and that it has been done with perfect safety I have no doubt. As a matter of fact, tooth paste was added to the list of products eligible for packaging in lead, and I am sure mil lions of people used it with complete safety. I must explain, however, that in all of these tubes an interior spray of a synthetic coating was used to protect the contents from any possible contamina tion by the lead. Here then was a large public experiment in the use of lead, where a hazard had been thought to ex ist, without any ill effects.
Some years ago I had a visit from two eminent professors of agriculture from western colleges who had been delegated by the apple-growing industry in the northwest to investigate the spray residue problem. They told me that the apple industry was threatened with ex tinction unless something were done to establish a tolerance for lead which they could meet. I urged a complete and im partial investigation, and, because of the public interest involved, suggested the use of the U. S. Public Health Service. Most of you know that this was subse quently done and that the Public Health Service issued an excellent report, the conclusion of which was that they did
8 WORMSER
not find a single case of lead poisoning where the exposure is most pronounced,
among the 1,231 persons examined in do not contain any lead.
the field, some subjected to high ex
There is little excuse today for spe
I
posure of the lead arsenate spray.
cialists in the field sticking their necks
Another example, in one mining state out with the assertion that orange juice
it was alleged that water emptying into squeezed in an aluminum cup results in
a beautiful lake used for drinking pur an attack of acute lead poisoning among
poses, a lake 75 miles away from active children, and publishing the results of
mining operations, had become so con the. investigation in a medical journal.
taminated with lead picked up by the Nor should doctors rely exclusively
water in a stream passing through mine upon the highly questionable evidence
tailings or waste rock from the mines, of an X-ray bone examination to deter
that tlie water was dangerous to drink. mine the presence or absence of lead
When we made an investigation, we poisoning in children.
found that the water samples from which Like my own field, engineering, the
the lead determination had been made field of medicine has grown so vast that
were merely gallon samples. Our pro it is beyond the bounds of human ac
cedure, on the contrary, was to use complishment to be familiar with all its
1,000 gal. samples, analyzing the ample ramifications. Therefore, I recognize we
residue obtained from evaporation. In have to he tolerant of those errors we
no case were we able to check the ana detect in the medical field from time to
lysts using the gallon quantities. I think time. Thanks in a large measure to the
this shows the danger in using small excellent work of the American Medical
quantities of water, or, for that matter, Association, through its Council on In
any other material in detecting extreme dustrial Health as embodied in the Bos
ly minute amounts of metal.
ton Conference on Lead Poisoning two
It has been interesting to me to see years ago, an important step forward
other investigations of a public nature has been taken in clarifying a good
also clear lead from undeserved criti many medical misconceptions about
cism. For example, a survey made of lead. I hope that the American Medical
the use of one drop of solder in sealing Association will carry on this good work
evaporated milk cans, or the examina indefinitely.
tion of the use of lead for weighting At the same time, I want to pay my
silk. If we had time, I should like to respects to two publications of the
tell you of our examination of numerous American Public Health Association
cases of lead poisoriing from white lead, under the auspices of its Committee on
especially in infants, but I have already Lead Poisoning. These two books, prob
expounded on that in a paper I pre ably well known, are: "Occupational
sented before the American Medical Lead Exposure and Lead Poisoning,"
Association two years ago. It is here and, "Methods for Determining Lead in
where anyone is apt to go astray on the Air and in Biological Materials," and
easy assumption that because white lead should be in the library of any doctor
is synonymous with fine paint, all paint serving the lead industry or at all in
contains white lead. This is not so, as terested in the subject. It seems to me
white lead has become a minority in also that ibis is a good time to pay
volume of the various pigments used tribute to another agency which is sin
for painting in the United States. Most gularly able to work in the field of in
interior paints, and furniture paints. dustrial toxicology in a most construc-
DUP050314364
OPENING ADDRESS
9
tive manner; namely, the U. S. Public and government authorities could de
Health Service. Particularly in the rive a vast amount of data in the pub
highly important field of analytical lic's and industry's interest. I subscribe
methods in diagnosis, the work of the to that opinion. One of the things we
U. S. Public Health Service has been are doing here today is to develop an
outstanding. This is the very corner exchange of information from which
stone of medicine, for faulty diagnosis certain conclusions can be drawn, and h has lead to many misstatements in the I am hopeful, as time goes on that the
field.
Lead Industries Association itself, under
Even prior to diagnosis is the' im Mr. Bowditch's direction, will be able
portant question of verification of ex to develop surveys of great value to us
posure. In today's Conference we do all.
not have to worry about proving ex
For instance, I have always felt it
posure, because we are dealing in areas extremely pertinent that in our own lead
where the greatest hazard exists; name mines, and, so far as I know, in most
ly, in the actual production and manu lead mines, we have no trouble from
facture of lead or lead articles. We shall the metal. The chief health hazard un
all, therefore, be interested in hearing derground is silicosis, but, no doubt,
of the progress that has been made in the precautions which are taken to lay
the diagnosis and treatment of lead poi silicious dust in metal mining operations
soning. Although I realize that great also account for the excellent health
progress has been made, I do not think record in lead. In addition, of course,
industry will ever rest content until we there is the extremely high insolubility
reach perfection and that no one is hurt of galena, the lead sulphide. In a sim
by the production or use of any lead ilar manner, the experience of the prim
product. In this battle the prevention of ary lead smelters and secondary lead
exposure is our principal weapon. That smelters, the experience of our white
is also where great improvement has lead plants, storage battery industry and
been registered. By keeping lead out others, would be very useful.
of the atmosphere and by personal The late Dr.' Frederick Hoffman, as
cleanliness, the lead hazard in manu we know, endeavored to acquire a lot
facturing operations has been largely of useful information from an examina
overcome, as you well know. This prog tion of a nationwide compilation of
ress, I am confident, will be continued death certificates where lead was indi
as more people realize that, not only cated as a cause of death. This was an
from a humanitarian standpoint, but excellent project. Even though a lot
from a practical dollars and cents stand of the certificates were of questionable
point, it pays to improve hygienic prac statistical value, I would like to see more
tices.
of this done. Indeed, the more I study
In one of my numerous conferences our lead problems, the more I am con
with Dr. Aub, he once made an observa vinced that lead has nothing to fear
tion which I thought most helpful. It from the truth, and nothing but the
was that because of the widespread use truth.
of lead in industry, in so many different So important has the subject of lead
products, and in so many different hygiene always appeared to the directors
plants, industry itself constituted a great of the Lead Industries Association, that
laboratory from which, if proper rec some time ago they authorized the ap
ords were kept, the medical profession pointment to its staff of a fulltime direc-
DUP05031 4365
10 WORMSER
tor of health and safety, giving him ference, I want to express my deep
carte blanche to operate in the field, thanks to you all for coming, and to
with no reservation whatsoever. As a express my pleasure at being here where
matter of fact, this was also the basis I can listen to you.
on which I operated when I was active
Now it is my pleasure to turn the
ly engaged for the Association in doing meeting back to our Chairman. Mr.
what I could to help improve hygienic Bowditch.
conditions in our industry. My Board
Ch a ir ma n Bo w d it c h : Our next
never imposed any obstacle; their only speaker was for many years director of
thought was to get at the scientific truth and to use it to the best advantage of the public which they serve. 1 am con fident that it will always be the policy of the lead industry, comprising as it
the Industrial Hygiene Laboratories of the Chrysler Corporation in Detroit. Now, with Dr. Stuart F. Meek, who I am glad to say is also with us here, he
does, mining, refining and manufactur is conducting the Industrial Health, Hy
j
ing, now I am happy to say, all over giene and Safety Service in Detroit. Dr. the world, and so in opening this Con Gordon C. Harrold.
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SOLUBILITY AND PARTICLE SIZE IN LEAD POISONING
By GORDON G. HARROLD, Ph.D. crnd STUART F. MEEK, M.D. Industrial Health, Hygiene and Safety Service, Detroit, Mich.
I have been most impressed with the remarks that have been made. I was probably more impressed with one of the earlier remarks, to the effect that everyone wanted to get on with the meat of the meeting. Being part of that meal, I beseech your indulgence. For the more carnivorous members, this work will be published under the auspices of myself and Dr. Meek.
INTRODUCTION
In a previous study1, we provided evidence that lead chromate inhaled or ingested by human subjects did not exhibit clinical or laboratory findings indicative of lead absorption after ex posure to quantities of lead chromate greatly in excess of those regarded as safe for continuous exposure. That study involving two groups of 145 men and 40 men for 16 months was ex tended to 28 months for 20 men who were still exposed to high concentra tions based on an exposure day.
We will, in this report, extend the observations to 40 months for 26 men, and in the second part of the paper, present data on men exposed to lead metal fumes. The information is evalu ated in terms of the solubility relations of lead salts in human lung fluids2 and in terms of particle sizes.
RELATIVE TOXICITY OF LEAD CHROMATE
Exposure to PbCrO*
In our previous report on the toxicity of lead chromate1, we evaluated the ac tual exposure of two groups totalling 185 men to amounts of lead in the form of lead chromate, never less than 4.0 mg. of PbCr04 per exposure day for 18
months, and to over 18 mg. PbCrO.. per exposure day for from 12 to 15 months, with no clinical or laboratory symptoms of lead absorption.
From the above group, 26 men were selected on the basis of continuous ex posure to the highest concentrations of lead chromate. They had exposure days averaging 6.2 mg. of lead chromate for 27 additional months. The reports showed no laboratory or clinical results differing from the normal.
This group of 26 men had exposure days of over 18.3 mg. lead chromate per day for 13 months, and to 6.2 mg. lead chromate per day for 27 additional months. The highest exposure day was 12.2 mg. and the lowest was 2.6 mg. in this 27-month period. The men on the job cooperated by wearing the test collecting devices. At the end of 40 months, the group basophilic aggregation was 0.7 and the lead-in-urine average 0.039 mg. per liter. Again, no clinical or laboratory results deviating from the normal were found.
The above extension of the test results of the group, whose only selection was on a basis of continuous exposure to high quantities of lead chromate, indi cates that over long periods of time, such exposure does not cause demon strable ill effects.
In view of Silverman and Drinker3 questions about physiological breathing rates, our last results for a period of 15 months with this group of 26 men were derived mainly from the exposure days of the men on the job. All the men cooperated to some extent, and no significant deviations were noted from those results which had previously been extended from a limited number of men. These tests were not taken every day, but some values were obtained
11
DUP050314367
12 HARROLD- MEEK
every two weeks from different indivi men had worked for over 15 months
duals. The individual differences which reported lead-in-air values of 74, 105,
did appear were not important to the 118 and 121 mg. of lead per ten cubic
general average over a long period of meters of air using the electrical pre
time. The actual exposure time of no cipitator as the collecting instrument.
worker was reduced for more than two Since such methods of standards re
weeks over the total exposure lime by porting, based on the air content of con
the wearing of test equipment.
taminant per ten cubic meters of air,
Efficiency of Packed Tube Collector
are commonly employed, it can be seen that some explanation is required as it
The efficiency of the "packed tube col is determinable that lead absorption of
lector1" was checked at 28 and 40 liters lead compounds such as lead oxide,
airflow per minute using an electrical when reported in much smaller concen
precipitator in a series. Three determi trations, have caused lead absorption.
nations averaged 99.7 percent relative Thus, our correlations4 between lead-
efficiency at 28 liters per minute, and in-urine and basophilic aggregation were
three determinations at 40 liters airflow good when lead oxide was involved.
averaged 99.8 percent relative efficiency. Furthermore, our first lead chromate
The lead test material was sprayed lead report1 cites the excellent agreement
chromate in concentrations of 120 to 150 between basophilic aggregation, lead-in
milligrams of lead chromate per ten urine, and lead content of the air when
cubic meters of air as determined by the lead oxide is involved. We have addi
electrical precipitator.
tional information supporting this point.
Air Lead Concentrations Per Ten Cubic Meters
Two hundred and one (201) men ex posed to concentrations of lead-in-air averaging 1.24 mg. of lead per ten cubic
However, the concentrations that this meters had a basophilic aggregation
group of 26 men were exposed to based on the amounts of lead chromate per ten cubic meters of air using the elec trical precipitator and the midget impinger as sampling equipment were much higher. The averages comprise 328 individual air tests for the first 13-month period, and 628 separate air determinations for the 27-month period. For 13 months, the exposure average was 117.1 mg. of lead chromate for ten cubic meters of air. For the following
average of 0.9, and the lead-in-urine average was 0.081 mg. per liter of urine.
Other investigators5' have somewhat similar data which refer in the main to the soluble lead compounds--compounds readily soluble in body fluids.
We have found that when lead chrom ate1 was involved, this correlation was not evident. There is a correlation be tween the basophilic aggregation and the lead-in-urine, but none with the amounts of lead-in-air.
27 months, the average was 41.3 mg. of lead chromate per ten cubic meters of
HYPOTHESIS
air. The lowest values found in one area Our work2 on the solubility of lead
where two of the men were working salts in human pleural fluid shows that averaged 12.1 mg. of lead chromate per lead oxide and lead carbonate are much ten cubic meters of air for the last six more readily soluble in human lung
months' exposure period.
fluid than lead chromate and lead ti-
An outside agency checking one of tanate. This fact, when isolated from
the work places where some of these 26 the actual concentrations, is only im-
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SOLUBILITY AND PARTICLE SIZE
13
portant in that it allows a prediction that the more soluble salt will probably cause signs of lead absorption to appear more rapidly than in the case of the less soluble salts.
However, we believe the quantitative evaluation of the amounts of impure lead chromate in human pleural fluid2, indicates a possible explanation of the lack of harm due to very large quanti ties of inhaled lead chromate. It has been suggested that the synthetic coat ing on the lead chromate paint would prevent the dissolving of the lead com pound in the human organism, but this is not a noticeable deterrent to lead intoxication when paints containing lead oxide, lead sulphate, or even lead carbonate are sprayed.
Furthermore, we did not use a coated lead chromate in our solubility deter mination.
These quantities had not been re ported in the literature for the solubility of the lead oxide, lead carbonate, lead chromate, and lead titanate in human pleural flqid or blood serum prior to our recent paper2. We are now suggest ing a possible explanation which has been offered freely in the past based on generalized information or belief. We now have scientific data to substan tiate these beliefs.
We propose an explanation based on the extremely low solubility of lead chromate in human pleural fluid and blood serum. The amounts found solu ble in one liter of these fluids range from 1.28 mg. PbCr04 in pleural fluid to 1.14 mg. PbCrO, in blood serum. Since the total amounts of tissue fluid which could act as an exchange medium between the lung and the blood are limited, a saturation of this limited quan tity of fluid would provide total quanti ties of lead ion less than 1.0 mg. This quantity of lead is subject to a contin uous unbalanced equilibrium with the
blood, and finally with the kidney and the excretory product, the urine. The maintenance of saturation of these fluids would require, according to the laws of mass action, very large quantities of the less soluble lead chromate in the lung. When it is considered that usually, but not always, no clinical symptoms are observed when 0.2 to 0.3 mg. of lead are found in a liter of the urine and amounts of 0.05 to 0.1 mg. of lead per 100 grams of whole blood, the possibili ties of getting even 0.5 mg. of lead in the body fluids from a quantity of lead chromate of 1.0 mg. per liter of body fluid concentration is remote in even exceptional industrial exposures.
This information may appear more significant if we point out that 0.05 mg. to 0.1 mg. of lead per 100 grams of whole blood is close to 0.5 to 1.0 mg. of lead per liter of blood. We, therefore, are comparing 0.2 to 0.3 mg. lead in the excretory product, the urine, to 0.5 to 1.0 mg. of blood lead in the same vol umes of fluids to a compound which dissolves in blood serum in the range of 1.14 mg. per liter.
Actually, our measurements of 26 men exposed to. at least 6.2 mg. of lead chromate for over 40 months, and for a large portion of the time to from 15 to 20 mg. per day, showed that this saturation was not only not reached, but that the lead-in-urine and basophilic aggregation dropped to normal during a period of time when the exposure day indicated an inhalation of 6.2 mg. of lead chromate. Furthermore, for 13 months of exposure to over 18 mg. of lead chromate, no significant deviations were noted from the results observed at the end of one month's exposure.
Based on these observations, we sug gest that the insoluble lead salts which prove to have solubilities in the range of 1 mg. or less in human lung fluid at about 37C. will not be likely to be
DUP050314369
14 HARROLD-MEEK
causative of lead intoxication from in halation in quantities of less than 20 mg. of insoluble lead compound per ten cubic meters of air. We do not propose this as a standard of the M.A.C. variety, but we do suggest that it is a fact based on scientific observation.
It is our observation that even this figure may be extended considerably if more insoluble lead salts are considered. Thus, with purified lead titanate where the solubility is about 0.28 mg. PbTiCfi per liter of blood serum, we may be approaching a range where a true equi librium exists between the amounts of lead absorbable through inhalation and the amounts excreted without harm to the human organism. This relation would not obtain with impure lead ti tanate containing lead salts readily solu ble in body fluids. It is believed that any lead intoxications which may occur in a lead salt of this level of solubility would be due to the admixture, or for mation, of a more soluble lead com pound.
SOLUBILITY, PARTICLE SIZE AND EXCRETORY RATES
Our study of workers exposed to lead chromate1 has led to the question as to whether or not somewhat higher levels of urinary excretion than that of the general population can be maintained without the demonstration of clinical symptoms.
In the cases of over 100 men exposed to large quantities of lead chromate, the urinary lead excretory rate rose to 0.1 mg. per liter of urine and remained above 0.06 mg. per liter of urine for 18 months with no demonstrable damage. Certainly there must be some regulatory mechanism to adapt the organism to changed conditions. In a previous study4, we were able to show that the average individual in an industrial en vironment, exposed to more lead than
the normal population, did have a some what higher lead excretory rate of 0.05 mg. per liter of urine than had been reported for the general population7. This indication has been supported by Dreessen8 in his study on lead storage battery workers not exposed industrially to lead, whose urine contained 0.06 mg. of lead per liter.
That this rate is in equilibrium with the exposure is shown by the return to completely normal industrial levels, both for lead-in-urine and for basophilic ag gregation test, even though exposed to over 6.0 mg. of lead chromate when in the air of the work place, and over a longer period of time, approaches the normal values given for the general population.
While we have, until this point, been concerned with the solubility of lead salts as related to the environment and the effects on humans, we wish also to discuss the effects of particle size on solubility, rate of absorption, and rate of excretion.
In the case of the melting of lead compounds and alloys, it has been re ported9 in connection with brass found ries that there is not too much appre hension in this group concerning lead intoxication. This has also been our experience and that of others.
It has also been reported that the correlation of lead-in-air, lead-in-urine, and blood stippling is not good. Stalker9 reports his findings that where the at mospheric lead is in three out of four foundries, below 1.5 mg. per ten cubic meters of air, the urinary lead was ex cessive for 34 percent of the workers.
They also noted other work where urinary lead of from 0.18 to 0.21 mg. per liter with air concentrations ranging from 0.29 mg. per ten cubic meters to 11.8 mg,, and under winter conditions, 38.5 mg. in pouring areas.
Finally, it was noted that only 31
DUP050314370
SOLUBILITY AND PARTICLE SIZE
15
percent of the eases having high urinary value was 43.6 mg. The lead-in-air
lead (over 0.15 mg. per ten cubic me concentration shown in column 1, Table
ters) and 42 of the workers with high I, representing conditions two years
blood lead (over 0.07 mg. per 100 earlier averaged 24.6 mg. of lead per
grams) had high stippling (over 1,800 ten cubic meters of air.
per million). While in general agree
The lead-in-air average in the pouring
ment with the doubts generally ex area of 23 samples was 16.4 mg. The
pressed about the non-specificity of stip lowest value was 8.1 mg., and the high
pled erytherocytes for specific and sin est was 21.2 mg.
gle cases, we think it interesting to note The particle sizes involved ranged
the above small percentages of high from 0.1 [i or less to 1.0 ix for 98 percent
stippling values when most of the evi of the particles with over 90 percent of
dence submitted tends to the belief that the particles less than 0.5 it.
greater percentages of high stippling The urinary lead average for 20 ex
would occur due to the fact that these posed individuals in the melting areas
cells appear from many other sources. was 0.445 mg. per liter, and the average
Sanders10 has shown that stippled ery reported two years previously was 0.46
therocytes are not too reliable in single mg. per liter.
cases, and should be viewed with caution The urinary lead average for 13 ex
in group studies.
posed individuals in the pouring area
We4 have shown in a limited number was 0.31 mg. per liter.
of old lead cases that the basophilic Table I shows the variations existing
aggregation did not truly reflect those in individual samples, as well as the
conditions presumably existent in the fact that the average some two years
men concerned.
later was slightly lower than the first
Finally, Stalker's8 report states that samples of urine. In the composite
a group with the highest urinary lead- melting area exposures, some of the
in-urine values did not significantly vary samples of urine in the second column
from a general group of foundry work were checked by a polarographic meth
ers as regards the physical signs of lead od and good checks were obtained.
poisoning displayed on medical exami
These results are considerably higher
nation.
than the other reports we have seen,
We have recorded studies on 33 men and yet in no instance, to our knowledge,
exposed to brass fumes. These are pre have the men made complaints, or been
sented because they' add some data re away from work. It is realized that
lating to the problem of lead poisoning these cases represent too few to gene
in relation to soluble lead oxide in the ralize from, but in conjunction with
finely divided state and in somewhat other reports in the literature, it brings
greater exposures than usually reported up one fact and that is that much higher
in the literature.
lead-in-urine values seem to persist
Twenty-eight air samples were collec when the lead is: (1) soluble in body
ted by the electrical precipitator and fluids, (2) small in particle size.
analyzed by the dithizone method re
As our lead chromate exposures indi
ported by Harrold, Meek and Holden11. cate that there is a considerable varia
The lead-in-air average was 30.2 mg. of tion in the amounts of lead-in-urine com
lead per 10 cubic meters of air in the pared to the clinical symptoms and the
melting area. No values of less than lead in the form of insoluble lead com
19.7 mg. were found, and the highest pounds in air, there is also some varia-
i DUP050314371
16 HARROLD- MEEK
Table I
Melting Area
Pouring Area
Initial Tests Average lead-in-cir
24.6 mg. per 10 cubic meters.
Number of Men Ex posed -- 20
Cheeks two years later
Average of 28 samples 30.2 mg. of lead per 10 cubic meters of air;
High value 43.6 mg. lead per 10 cubic meters of air;
low value 19.7 mg. lead per 10 cubic meters of air.
Urinary Lead in mg. per liter
1.01 0.06 0.57 1.04 0.41 0.59 0.68 0.95 0.74 0.21 0.58 0.34 0.04 0.49 0.15 0.48 0.14 0.05 0.60 0.15
Urinary Lead in mg. per liter
0.74 0.10 0.68 0.44 0.51 0.47 0.60 0.33 0.58 0.34 0.61 0.42 0.08 0.48 0.40 0.58 0.15 0.41 0.76 0.21
Ave. 0.46 mg. lead per liter of urine
Ave. 0.445 mg. lead per liter of urine
tion between the lead-in-urine and leadin-air when the special cases arise of finely divided lead oxide which is very soluble in body fluids.
Hypothetically, it may be that such circumstances may lead to a more rapid transport of the lead into the urine with its removal consequently unbalancing the equilibrium between the lead in the lung and tissue fluids and the blood so that this lead is excreted in larger quan tities than are considered normal based on our usual experience. Of course.
Average of 23 samples, 16.4 mg. lead per 10 cubic meters of air.
High value, 21.2 mg. lead per 10 cubic meters of air.
Low value 8.1 mg. lead per 10 cubic meters of air. Number of men exposed -- 13.
Urinary Lead in mg. per liter
0.21 0.44 0.47 0.36 0.38 0.51 0.22 0.16 0.14 0.17 0.48 0.14 0.34
Ave. 0.31 mg. lead per liter of urine
small particle size carries other conno tations which will be discussed later.
There are other unpublished instances involving several hundred men where the lead-in-urine has been higher than we have reported without public or private reports of outbreaks of lead in toxication. Elkins14 has pointed out the lack of appreciation for urine test data among industrial hygienists. We would like to caution against the setting of fixed and arbitrary lead-in-urine values because of the apparent variability of this factor as influenced by the chemi cal and physical characteristics of the lead compound involved.
This point of view has been well stated in Hamlin and Weber's15 study in the brass foundry industry where they found that lead intoxication rarely occurred unless the rate of excretion was over 0.3 mg. lead per liter of urine and that values up to 0.2 mg. lead per liter of urine did not have definite signifi cance. They state that marked correla-
DUP05031
SOLUBILITY AND PARTICLE SIZE
17
Table II
Table 111
Lead Soldering Fumes
Lead Melting
Pb in air Pb in urine
Number of mg. per 10 mg. per Basophilic
Persons cubic meters liter Aggregation
ExposedAverage Average
percent
29 Less than 0.5 0.12 63 " 1,0 0.14
67 77
tion exists between the lead intoxication, lead-in-air and in urine. T'he disagree ment of Stalker in his study of Kentucky foundries is partly attributable to the very low range of lead-in-air reported. Our experience with larger lead-in-air exposures duplicates Hamlin and Web er's experience, but considering the mat ter- of fine fume coupled with the great solubility in human body fluid of the lead oxide involved, the appearance of high lead-in-urine values, from very small amounts of lead-in-air, is expec table. Our available evidence does not indicate serious lead intoxication from other lead-in-air exposures in lead smelt ing operations, or operations where only heated lead is involved in moderate con centration.
In the lead soldering fume work shown in Table II, the air test average represents samples taken every two months for five years. Some of the leadin-urine data are represented by persons exposed four years and some five years. Each average is composed of lead-in urines determined at three to four month intervals on all the exposed personnel and the basophilic aggregations were taken at the same lime.
In the lead melting operations. Table III, air tests were taken ever)' three to four months. Lead-in-urine and baso philic aggregation were taken every four to six months for eight years.
The tests in this table were selected from several thousand on the sole basis of having data available for a reason ably long period of time from various
Pb in air Pb in urine Number of mg. per 10 mg. per Basophilic
Persons cubic meters liter Aggregation Exposed Average Average percent
11 Less than 1.0 6 " 1.0 4 " 0.5
0.18 0.22 0.16
86 81 72
molten lead operations.The operations involved had a low percentage of labor turnover. That data would agree with the view that there is no correlation with lead-in-urine and lead-in-air values though none of the various physicians who examined the men ever found any clinical symptoms, nor do we have any record of sickness in these people which would suggest lead poisoning.
SUMMARY AND CONCLUSIONS
Our experience with large numbers of lead-in-urine values correlated with basophilic aggregation percentages and lead-in-air concentrations leads us to accept a variable lead-in-urine value, a variable lead-in-air, and a variable baso philic aggregation, depending entirely on the lead compound and state of sub division involved. Hamlin and Weber's15 experience in a brass foundry' is cor roborated for brass foundries, and per haps for all very finely divided lead oxide and lead vapor exposures.
It may not completely represent the case even in some types of lead solder ing because of the coarser lead oxide dross which is sometimes an important factor.
The same situations do not appear when very insoluable lead compounds, in any state of subdivision, are being considered.
It may not follow, nor should we be construed as believing, that lead fume does not cause lead poisoning. It can
DUP050314373
18 HARROLD - MEEK
and it does, but we are pointing out spiratory flow rate. These factors are
that it is entirely probable that larger related to the more energy-consuming
amounts of lead-in-urine may be found tasks in foundry work.
when finely divided, soluble lead com
The increase in dissolved lead of
pounds are involved than are usually small particle size (less than 0.5 ft) is,
accepted as standards, and rightfully so moreover, markedly increased due to
for the usual exposures to lead com the much larger surface area involved.
pounds readily soluble in body fluids.
We believe that this factor, coupled
We, likewise, do not conclude that with the high concentrations of lead
t lead chromate cannot cause lead poison oxide found per unit volume of pleural
ing under certain conditions, but the fluid, markedly increases the rate of
evidence we have presented makes the solubility in the body fluids, and that
appearance of lead intoxication from this lead is then transported and ex
this source highly improbable in the creted at higher levels than would be
industrial exposures which are likely to the case with the slowly soluble, larger
be encountered. This conclusion is based size particles. Within certain limits typi
almost entirely on the solubility charac fied by 1.0 mg. lead per liter of blood
teristics of this compound. In those and 0.3 mg. lead per liter of urine, this
instances where the amounts of lead lead will usually cause no harm, where
compounds which can be dissolved in as it is more likely that larger sized
body fluids, are equal to, or less than, particles in those concentration levels
the amounts which are transported and will cause damage. This concept is, of
eliminated without harm to the organ course, still dependent on the total dos
ism, the potential saturation limit is the age of lead available to cause damage,
important factor. The factor of solu as is usually the case. However, with a
bility, in this instance, is independent of rapid transport rate in the body fluids,
particle size and, perhaps, of other pos the non-exposure periods away from
sible influencing factors, whereas lead the work environment provide an in
compounds soluble to a great degree in creased opportunity to keep a lead level
body fluids are dependent on particle which will not become critical, whereas
size, both in regard to the rate of for the, soluble, but larger sized lead
solution and other factors such as the oxide particles, an accumulation of the
transport of extremely fine particles in working day will not be so readily dissi
protecting envelopes.
pated.
The question of particle size in dust The limiting value in the case of less
exposures, principally relating to silica, soluble lead compounds is, then, the
has been re-evaluated recently.121 3
solubility in body fluids which does not
In particular, Landahl and Herr exceed a certain excretion rate which is
mann13 have indicated that from 20 per readily maintained without noticeable
cent to 35 percent of the particles in the harm.
size range from 1.0 ft to less than 0.1 /i The mechanism of transport of ex
are retained in the lung, and further tremely finely-divided lead is not clear.
reduction in size indicates increasing The. work of Aub16 and Brooks17 has
retention. They further show that in been challenged by Kehoe.1,s It is pos
creasing the inspiratory flow increases sible that when the lung receives parti
the efficiency of lung retention of small cles of less than 0.1 micron, a process
particles below 1.0 micron as does in akin to gaseous diffusion may result and
creasing the tidal air at a constant in that a film may permit the transport of
DUP050314374
SOLUBILITY AND PARTICLE SIZE
19
the lead particles in the blood stream relatively unchanged. It is speculatively possible that the removal from the lung of the dust particles by dust cells or phagocytes may be accomplished with out preliminary dissolving. While it is true that colloidal lead compounds may form other chemical compounds and act as soluble lead salts in the blood stream as described by Kehoe18 it is, never theless, not proved that the very finely divided lead dusts which we are talking about act as colloidal lead under the experimental methods of intravenous administration employed in these stu dies. The instances of increased urinary lead in humans referred to in this paper may be confirmation of transportation, protected in some unknown manner,
without chemical transformation or change. Whether this be true or not, Kehoe18 has stated "There is an equi librium established with an environment in which lead absorption was unavoid able," and "that the presence of larger amounts of lead in the excreta long after experimental administration should not be interpreted as evidence of reten tion by the tissues."
Our conclusion is that somewhat larger than usual lead-in-urine values may appear when the exposure to at mospheric lead is in the form of finely divided particles, and that the appear ance of larger amounts of lead-in-urine in these situations may not be indicative of actually, or even potentially, harmful atmospheric exposure.
BIBLIOGRAPHY
1 Harrold, G. C., Meek, S. F,, Collins, G. R., and Markell, T. F., "Toxicity of Lead Chro mate," /. Ini. Hyg. & Tox., 26, 47, (1944).
-Havrold, G. C., "Solubility of Lead Salts in Human Pleural Fluid and Blood Serum," (To be published).
sSilverman, L. and Drinker, P., "Use of the Exposed Worker as an Air Sampling Unit for Contaminants," J. Ind. Hyg. & Tox., 27, 22, (1945).
*Meek, S. F,, Collins, G. R., and Harrold, G. C-, "Correlation Coefficient Between Baso philic Aggregation Test and Lead-In-Urine," J. Ind. Hyg. & Tox., 22, 401, (1940).
'Elkins, H. B., Ege, S. F,, and Ruotolo, B. P., "Evaluation of Lead Hazard," J. Ind. Hyg. & Tox., 23, 256, (1941).
Smucker, C. H., and Kistler, J. B., "The Evaluation of the Lead Hazard in the Decorat ing Department of a Glass Plant," J. Ind. Hyg. & Tox., 24, 1, (1942).
7Kehoe, R. A., Thamann, F., and Cholak, J., "Normal Absorption and Excretion of Lead," J.A.M.A., 104, 90-92, (1935).
8Dreessen, W. C-, "Health of Lead Exposed Storage Batter)' Workers," J. Ind. Hyg. & Tox., 25, 67, (1943).
9Stalker, W. M., "Lead Exposure in Brass Foundries," J. Ind. Hyg. & Tox., 29, 94, (1947).
10Sanders, D. W., "Measurement of Indus
trial Lead Exposure by Determination of Stip pling of the Erytherocytes," J. Ind. Hyg. & Tox., 25, 38, (1943).
1 -Harrold, G. C., Meek, S. F-, and Holden, F. R., "A Practical Method for the Rapid De termination of Lead When Found in the At mosphere," }. Ind. Hyg. & Tox., 18, 724, (1936).
12Hatch, T,, and Hemeon, W. C. L,, "Par ticle Size in Dust Exposures," 3. Ind. Hyg. & Tox., 30, 172, (1948).
13Landahl, H. D., and Herrmann, P. G., "On the Retention of Air-Borne Particulates in the Human Lung," J. Ind. Hyg. & Tox., 30, 181, (1948).
14 Elkins, H. B., "Urinary Excretion of Industrial Poisons," Ind. Hyg. Nevis Letter U.S.P.H.S., Vol. 8, No. 10, page 14, (1948).
15Hamlin, L. E., and Weber, H. S., "Control of Lead Hazard in Brass Foundry Industry," 1. Ind. Hyg. & Tox., 29, 367-377, (1947).
16Aub., J. C., et al; "Lead Poisoning," Med. Monographs 7. p. 24, (1926). Wms. & Wilkins.
17Brook, John, "The Interaction of a Finely Divided Lead Suspension With Blood Serum, Ringer Solutions, and Aqueous Phosphate Solution," Bio. Che. ]. 21, 766, (1927).
lsKelioe, R. A., Thamann, F., "The Be havior of Lead in the Animal Organism--III Colloidal Lead Compounds," /. Lab. & Clin. Med., Vol. XIX, No. 2, 178, (1933).
DUP050314375
2D DISCUSSION
Ch a ir ma n Bo w d it c h : We have now reached our first discussion period. Dr. Joseph Aub was to have led the dis cussion of Dr. Harrold's paper. When I saw Dr. Aub in Boston last Thursday, I found him greatly overworked and not feeling too well and I did not have the heart to try to pressure him into keeping this engagement, sensing that he really felt that he should not.
I thereupon sent an S.O.S. to another lead authority and friend, this one in New York, and it was characteristic of her that she wired me here in Chicago to say that she would be happy to under take this assignment, adding that she
would arrive in Chicago yesterday, and if there were any further matters in con nection with the conference in which she could help, she would be only too glad to do so.
She is an authority, widely read and quoted, on almost all subjects of indus trial hygiene, and is a member of the Committee on Lead Poisoning of the American Public Health Association. She has been associated with the Divi sion of Industrial Hygiene of the New York Labor Department since 1923, and has been its assistant director and chief of the Medical Unit since 1937. Dr. May R. Mayers.
DISCUSSION
f Dr . May R. May er s [New York State small for the support of a thesis of such
Department of Labor, New York, N. Y.]: importance. I think it is very sugges
Mr. Bowditch seems to have these dates tive. I am sure Dr. Harrold must feel
very much more clearly in mind than as I do, that there are a lot of questions
I have, and I am really surprised to which have arisen in connection with
find that one can play around with this piece of work on which he would
industrial hygiene for that many years like further data, just as I would. No Ji and still get a lot of fun out of it I doubt he will some day be able to pre
guess it is an interesting reflection on sent it to us.
the field.
It would be very interesting, for exam
I am sorry Dr. Aub is not able to be ple, to learn, with reference to a less
here this morning to discuss Dr. Har soluble lead compound such as lead
rold's paper. I would, myself, be great chromate which, presumably, is ab
ly interested to get his personal reactions sorbed into the blood stream slowly,
to it. It is a very interesting paper. As and is present there in relatively low
it is, I would say that, perhaps, I am concentrations, whether the excretion of
more sorry than you are that I have that material will continue for a much
had to pick up this assignment at the longer period of time than is the case
last minute. But I am very glad to give with a soluble lead oxide which goes
you my thoughts on it.
in and out, perhaps, more rapidly. I
Dr. Harrold has presented a very in think that would be quite interesting
teresting thesis in connection with the to know.
matter of solubility and particle size as On the other hand, I feel that we
it influences the excretion of lead in the ought to know, before drawing too
urine, and lead intoxication; and he has many conclusions, a lot more about the
presented some very interesting data actual stages of absorption and trans
with reference to it.
portation of the lead chromate in the
Perhaps my first feeling about the body. There is quite a jump in the
data is that the numbers are a little bit paper, I think, between lead in the air
DUP050314376
SOLUBILITY AND PARTICLE SIZE
21
and lead in the urine. Lead appears in large (and that is true not only of lead
the blood; some of it is stored before but it is true of many other substances
it appears in the urine.
as well) in an individual worker there
Dr. Harrold apparently has not been is not necessarily any correlation be
able, as yet, to provide us with neces tween signs of intoxication and his ex
sary data in the various situations he cretion in the urine, of that substance.
discusses, with which to more closely On the contrary, it has been very strik
correlate lead in the. air with lead in the ing that, where there is very little ex
whole blood and with lead in the urine. cretion, we have frequently found signs
I think that one must get much more of intoxication; and where there has
detailed information with reference to been a great deal of the substance ex
the in-between stages before one can be creted, there has in many cases been
entirely satisfied to draw too final con complete absence of intoxication. That
clusions on just what has happened; is something that I think one must never
why this lead appears in the urine in forget.
the way that it does, under those differ
In dealing statistically with this ma
ent circumstances.
terial, therefore, it is very important
I think that physicians are quite pre not to overlook these facts, and to make
pared to accept, though' we do it a proper allowance for them.
little bit reluctantly, the fact that there The other point I would like to men
has been demonstrated a very practical tion is the use of basophilic aggregation
usefulness in getting group urine sam in such a survey. It has its uses. How
ples for purposes of industrial control. ever, I feel that, when one is working
I think we are very anxious, however, out refinements, in terms of certain
that that not be confused with the prob special chemical and physical properties,
lems of protecting individual workers such as solubility and particle size, in
who vary greatly in their susceptibility. trying to differentiate between very
If one were to have astronomical num closely allied chemical substances, one
bers one could statistically, no doubt, must go further than merely investigat
iron out very satisfactorily all sorts of ing a single element, such as basophilic
variables, including variables in indivi aggregation and correlating that one
dual susceptibility. Within a small group element with all of these other factors
however and in the average practical in a complex picture.
situation in a plant, trying to protect First of all, basophilic aggregation,
the health of its workers, I feel that stippling, or any other single feature
whatever usefulness there is--and there merely represent special aspects of a
is a great deal of practical usefulness blood dyscrasia which is caused by lead.
in this group urinalysis for purposes of They are only elements in a very com
control -- it must always be supple plex hematological picture. I will not
mented with a great deal of attention to go into that; I do not want to take too
the individual worker's health and his long on this discussion. But the point
physical condition. Complete evidence is, I do not see that there is much value
of what is going on in his body, from in selecting a single element in a hema
the medical standpoint, must be corre tological picture for correlation with
lated with the particular findings in his these many other metabolic factors.
blood and his urine.
,
I think either you correlate the whole
Then, we are greatly impressed, as hematological picture or else you just
physicians, with the fact that, by and do not talk about it at all.
DUP050314377
22 DISCUSSION
I think this is brought out very strik ingly in our own experience with lead chromate. I am sorry that I am not in a position to present our findings in de tail. I did not have an opportunity to look over our files before coming here. But we have had some very interesting experiences lately in a lead chromate plant. It is a plant that converted from zinc chromate, during the war, to lead chromate only recently. The doctor in this plant called on us not so long ago to ask for help because he was having a lot of illness. The work is incomplete, because the doctor himself wanted to finish it, and we left it to him. As a matter of fact, he probably will not do so because there has been a reorganiza tion and he is now out, I understand. However, we are following the plant closely, but we do not have the final data; 1 wish we did have. But we have certain information which I think is very pertinent, and which I would like to mention briefly. That is, that whatever his positive findings were, they would not have been brought to light by an analysis such as Dr. Ilarrold's, which was confined to measurements of lead excretion, lead in the air and basophilic aggregation.
The changes in the blood picture found among our workers were related to other elements in the blood picture which gave us an idea, which we expect to work on, either to confirm it or throw it out. We got the impression from these blood findings, that the workers really had a very much greater depres sion of bone marrow function on ex posure to lead chromate than what one would ordinarily get with lead oxide or some of the more soluble lead sub stances.
We had a definite impression, on the other hand, that, with lead chromate perhaps because it was less soluble, workers were getting less acute lead in
toxication than one would expect. Indeed, we began to wonder whether
these workers were not actually getting a very different type of blood dyscrasia, from that ordinarily associated with lead intoxication. There was an unusu ally severe anemia, which was very re sistant to treatment. This troubled the plant doctor a great deal.
While I do not offhand remember [and, as 1 said, I did not have an op portunity to look up our files to get the precise data on it,] it is my impression that the lead concentrations in the air in this plant ranged somewhere between 2.0 and 8.0 mg. per 10 cubic meters, which is considerably less than in Dr. Harrold's experiments; and out of line with what Dr. Harrold's analysis of his experience would seem to indicate.
I mention that not to question the basic thesis Dr. Harrold presents, which I think is an interesting one, but I pre sent this experience of ours because I feel that, if one is going to go beyond the mere practical use of group sam
ples, for practical industrial control, one must drop that approach altogether and begin looking at the worker. There, again, I felt a great lack. Being a doc tor, I tend to look for medical evidence in a paper. I felt, personally, a great lack of medical data with reference to these people that were declared to have been uninjured, where (I do not remem ber the wording) apparently no injury to health was demonstrated.
As a physician, I have a feeling that, if I were to take the first block of people in that particular row and give them a physical examination, I would turn up a lot of abnormal findings. I think we can do that with every single person that comes inLo the office for a health examination. Whether we think the findings are significant or not is another matter. Whether we think they are sig nificant enough to even tell the patient,
t;
i I
L
DUPO 50314378
SOLUBILITY AND PARTICLE SIZE
23
is another matter. But, on the other these are just a few random thoughts.
hand, there are many things found.
Dr . Go r d o n C. Ha r r o l d (Detroit,
An experienced clinician looking over Mich.) : It seems as though I have to
a lot of medical data of that sort which get back on the platform. I do not dis
is found under certain conditions of ex agree with Dr. Mayers in general. We
posure tends to see a pattern, and that were discussing my paper just before
\ pattern is important. I believe for that this meeting started. reason, that every physical examination We have a paper which will be pub is, in the last analysis, an interpretation. lished in the December, 1948, Industrial
V There is no such thing as negative medi Medicine which, I think, illustrates bet
m cal findings in anybody. I would like ter than anything else our concerns and 8| very much therefore to see Dr. Harrold what is important. It is not our labora
I present us with detailed medical data, tory test as such, and it is not lead in
if he pursues this investigation further, itself. Put a piece of lead out and look
as I presume he will, because I think it at it forever: it will not hurt you. It is
is very interesting. We would then be how much damage there is to the indi
provided with something as a basis for vidual in which we have been interested
objective medical interpretations of our --and very much interested.
own in connection with the interpreta
We feel that, perhaps, this method of
tion of the laboratory data with refer detecting damage from lead -- and I
ence to lead excretion and lead in the mean real damage -- by porphyrin de
air which was presented to us.
tection in the urine is important. Por
I think we should get all those things phyrins, I think, are a measure of de
together, plus detailed hematological struction, damage and trouble in the
findings not merely as to stippling, but human organism. So, we have performed
the red cell count, the white cell count, some preliminary work after thinking
the differential, changes in morphology about the matter for a long time. We
and any abnormal cells which are found. would like very much to have some easy
We know that the blood dyscrasia in way of taking the urine and finding out
lead is characterized by an extraordi what the real damage is, as opposed to
nary number of abnormal cells consider just the amounts of lead in the urine,
ing the fact that, judging by red cell which may or may not be fully indica
count and hemoglobin, there is a very tive. We are in complete agreement on
mild secondary anemia. The drop in that topic.
red cells and hemoglobin is very small As far as the lead chromate data is
in lead workers, ordinarily. That was concerned, I still feel very strongly that
not true however with our chromate when you get down below amounts of
workers where the drop was significant lead that are transported by the normal
ly greater and suggested to us that there human population every day, we are
was perhaps a very different blood dys back in the public health problems of
crasia with which we were dealing.
the normal population. That may be the
I hope that some time we can give wrong attitude, but it is still a reason
you the completed data on that parti able suggestion.
cular experience, which we are going I do not want to take any more time,
to follow through, if the plant doctor but I did want you to appreciate that
is not going to be in a position to do it we do feel, with Dr. Mayers, the data are
himself.
not exhaustive in the sense we have cov
I hope I have not taken too long, but ered everything--we certainly have not.
DUP050314379
24 DISCUSSION
We have given you, I think,'some infor of thing that Dr. Mayers is talking
mation and we hope someone else can about, we do not have any. differentials
do more work on the subject. We cer between those lead chromate people. It
tainly cannot spend all of our time doing is purely the matter of an average. These
scientific work. There is the question men did not exceed certain quantities,
of making a living once in a while. around 0.1 mg., and they went down,
[Applause.]
again, after a period of 40 months, to
Ch a ir ma n Bo w d it c h : There are so 0.039 mg., which is really lower than
many among those present here who are the average industrial exposure in some
qualified to further discuss this subject areas of Detroit where they use a lot
that it is hard to know how to pick and of lead. We have checked that several
choose. So, I think I will simply ask if times.
there is anyone who would like to say
Ch a ir ma n Bo w d it c h : We still have
something further.
two or three minutes left in this dis
Dr . Al s o p h H. Co r w in [Johns Hop cussion period.
kins University, Baltimore, Md.]: I Mr . H. J. Weber [American Brake
should like to know if there has been Shoe Co., Chicago, 111.]: 1 would like
any attempt to correlate, in these lead to mention our experience in a brake
chromate cases, the mouth-breathers lining plant where we deal with lead
with the nose-breathers, because that sulfide. While the lead-in-air concen
might make a very great difference in tration might be as high as 10 mg. per
the amount of lead absorbed.
10 cubic meters, we have not in five
Dr . Ha r r o l d : As far as the cases years been able to demonstrate any
are concerned--and that is one reason symptoms or signs of lead intoxication
why we do not have exhaustive medical in the employees exposed.
data--these men were processed through Our experience also seems to bear
medical departments and they went out Dr. Harrold's statements about par
through physicians' hands, and they did ticle size. In our machining operations
the work on them. These data refer to where the particle size is large we do
the same men over a period, in the case not have any cases of lead intoxication
of lead chromate, of 40 months; that is whereas in melting operations we do.
three and a quarter years. There was This indicates that particle size has a ji nothing wrong with them, at least that definite bearing on lead intoxication.
the physicians could find in their normal
Ch a ir ma n Bo w d it c h : Is there any
check-up, without going into extra, de thing further?
tailed, scientific observations. One hun
Our next speaker has been in general
dred eighty-five men are quite a number and industrial practice in East Chicago
to work up in a detailed way. They are since 1912 and has been specializing
practical evaluations by the physician there in lead absorption and in alumi
in charge, of the man's suitability for num therapy.
work under the criteria of his own A member of the staff of St. Cathe
medical examination.
rine's Hospital and a former member of
The mouth-breathers and the nose- the Indiana State Board of Health, he
breathers in this particular instance were is consultant to the American Smelting
not determined. As I say, we do not & Refining Company, The Eagle-Picher
have and we did not have any suggestion Company, The Glidden Company and
of difficulty. On that basis, without, other industrial organizations in the
again, having done the exhaustive type East Chicago area. Dr. David R. Johns.
DU P050314380
THE TREATMENT OF LEAD POISONING--PAST AND PRESENT
By DAVID R. JOHNS, M.D.
Consultant, American. Smelting & Refining Co,, Eagle-Picher Co., and the Glidden Co., East Chicago, Ind.
I might say, before going on with intrude a little in saluting those pioneers.
this paper, that I do look at this picture Dr. Alice Hamilton, Dr. Aub, Dr. Fair-
from the general practitioner's stand hall, Dr. McCord, Dr. Kehoe, Dr. Lanza
point, having been in the general prac and many others. We of today are
tice of medicine since 1912 and having deeply indebted for their untiring ef
been associated with the lead industry forts in the years gone by.
for about 25 years.
Lead poisoning dates back to antiqui
I see these men and look at them ty and much has been written concern
from the standpoint of their family phy ing it for several hundred years. Today,
sician and as a general practitioner. I with the widespread use of lead in indus
think that, while as a physician I might try and the ever increasing demand for
claim some credit, I do believe that a its use, it still is a major potential cause
great deal of our success has been due of occupational disease among those
to the good housekeeping and the en who must come in contact with it in
I gineering features in the various plants. their daily work. I have had many battles with them But I, for one, have seen very little
and, probably because of those battles, lead poisoning in the last 10 or 12
m we have had better engineering and years. Lead absorption we do encoun
C better housekeeping.
ter in the course of our work, and it is
I, as a physician, visit my plants, this phase of the subject which I believe
that is, go out through them at regular, really concerns most physicians in the
stated intervals to see what the condi lead industry. To me there is only one
tions are in that plant
real type of treatment and that is pro
The subject assigned to me today phylaxis. I will not discuss the prophy
should offer little difficulty to any phy lactic phase as this will be most ably
sician who has spent some years in the done by other speakers on this program.
lead industry. Looking back over 25 The treatment of lead absorption or
years of being closely associated with lead poisoning, if a case is permitted to
this industry, he should at least find a go to that latter phase, begins at the
routine of treatment, from the many first sign of absorption as observed by
which have been suggested and prac the physician in his regular routine in
ticed, which would serve him well.
spection of the worker. And I might
The advent of the safety first move say that these men arc inspected month
ment about 40 years ago did much for ly; blood smears are taken, and the men
the safety of the worker in industry in are interviewed. I believe there is no
respect to traumatic injury but it was phase of occupational medicine where
20 years later before a great deal of a man's statement means as much as
attention was focused on occupational when one is determining whether he has
diseases. May I at this time pay tribute lead intoxication. Truly if we are to be
to the physicians who have labored so our brother's keeper there is no phase
valiantly in this field of human en of human life to which it applies more
deavor, the conservation of a human intimately than in the duties of a plant
life, the most precious asset in this physician. If evidence of lead absorp
world of today. So this morning may I tion is detected, and I mean early signs,
25
DUP050314381
26 JOHNS
such as constipation, a high stippled gineering skill, the monthly inspection
count, a moderately elevated lead urin and blood work is the outstanding part
ary level, or lowered hemoglobin, or red of the treatment of lead absorption.
cells, 1 do not wait for his blood or Naturally, other conditions such as con
other laboratory findings to be re stipation and low hemoglobin should be
checked in a week or two but advise im treated and properly checked.
mediately a quick inspection of his job There have been many ideas about
so as to correct his hazard but, more the treatment of lead poisoning; various
often, recommend a change in his em methods have been advocated and like
ployment to a less hazardous location wise many have been tried, and practi
in the plant. This is the most essential cally abandoned. Among these are sul
part of his treatment; to wait for a blood fur, sodium thiosulfate and, more re
count or a lead urine, possibly a month cently, vitamin C. However, one of the
later, to determine whether he should be oldest, magnesium sulfate for constipa
moved to another job, is to be derelict tion and potassium iodide for lead elim
in one's duty. This procedure and noth ination is still used to good advantage
ing else is usually all that one has to do by many physicians. The diagnosis
and a month later the worker is already "lead poisoning" to me implies the pa
on the way back to normal health. Pro tient has several of a number of symp
crastination in these measures is what toms, namely--pallor, nausea, colic,
leads to lead poisoning, and I, for one, generalized aching of body and joints,
see no need for a case of lead poisoning sleeplessness, changes in the blood pic
in a plant which avails itself of a regu ture which consist of a secondary anemia
lar attending physician, who has had with relatively high stippled count, and
some experience in the field of plumbism moderate or high lead urinary levels.
and has adequate laboratory facilities With several of these symptoms present,
at his command, and with the determi active treatment should be instituted at
nation of the plant officials and safety once. The treatment as outlined by Dr.
department to do their part. I may add Aub some years ago has been found
here that it is the physician's duty to extremely helpful. This consists of im
ascertain that a man's job has been mobilizing the lead present in the blood
changed and to see that he has been stream by means of the metabolism of
given sufficient time to recuperate in the calcium by which the lead is stored in
new location. I will also add that the the long bones of the body. Calcium
companies with which I am associated gluconate, intravenously, appears to act
have cooperated with me in a very satis very well and a high calcium diet is pre
factory manner. The job that industry scribed to be given when nausea sub
did in the traumatic field, they will do sides. Intestinal drainage by enema at
again in the occupational disease field. first, then salines are administered as
To the above, treatment I would add a complete physical examination of all lead workers each year; surely with all of the pathology attributed to lead some valuable information should be ob
the nausea lessens. The intense pain of lead colic is controlled by morphine and atropine, and also demerol. The sec ondary anemia is treated with hematinics and vitamins.
tained. This physical examination In those few cases which we treat for
should not be confused with the month lead poisoning the following orders are
ly inspections, interviews and blood what I give:
work. After good housekeeping and en I. Morphine and atropine or demerol
DUP050314382
*
TREATMENT OF LEAD POISONING
27
># for pain if severe.
that perhaps we can put aside the de
2. Daily enema, repeat if necessary. leading. Surely nature will eliminate
3. Calcium gluconate intravenously if the exposure is corrected.
and orally.
There is one item which to me is of
4. Sodium phosphate (Fleets) 3 some importance and I would like to
times daily when nausea subsides. present it to you with the hope that it
5. Heat to abdomen.
may be a part of your discussion. Should
6. Complete blood picture.
a man with active syphilis (positive
7. Stop enema as bowels begin to serology) but with no external lesion
function.
he employed in the lead industry? My
8. Soft diet the first two or three view's are that he should not be allowed
days, then full diet.
to w'ork in lead hazard. Lead and
9. Liver and iron for secondary syphilis appear to have a marked affin
anemia.
ity for the central nervous system. Why
10. Patient to be up as soon as colic should we permit a man to suffer the
subsides.
possibility of a double bombardment?
11. Give patient sufficient time before Industry should be concerned as to
return to work.
whether a central nervous lesion was
Inseparably tied up with the treatment due to lead as an occupational factor or
of lead absorption or lead poisoning is whether syphilis was the etiological
the evaluation of the lead blood smears factor.
or lead urines. I have used the blood Lastly there is a question which I
smear for stippled cell counts for 20 have been asked many times. Many years and it has served me well. Along writers and textbooks have answered it,
with the weekly inspections and inter but I have not agreed with them. The
views, I have had no reason to regret question is whether a man who has once
its use. We see some cases of extreme had lead poisoning should return to the
lead absorption and practically no lead same industry. My policy has been to
poisoning with the exception of a rare permit his return, hut if again in a
case of lead colic. I have no quarrel period of six months he shows signs of
with those who use the lead urines as lead absorption, to advise him to seek
their principal guide but I do believe different employment.
that there is a tendency at the present In conclusion, may I again point out
time to raise, in my opinion, the per that my remarks have centered chiefly
missible lead level to, perhaps, too high about prophylaxis and lead absorption;
a level, the normal lead urine being 0.05 of lead poisoning I could say it has been
mg. per liter. Why raise it five to eight encountered only on rare occasions. If
times that value? I, for one, am some the officials of our companies, together
what afraid to do so.
with the safety engineers, and the medi
The question of deleading a patient cal department keep ever before their
is one in which opinion is divided. Some eyes that slogan enunciated 40 years
patients I have deleaded and others I ago, by those pioneers of safety, "Eter
have not. I can see no appreciable ad nal vigilance must always be the price
vantage for those who have been de of safety," then the worker in the lead
leaded over those who have not. As industry is in safe hands and the saying
the lead hazards in industry are lessened written many centuries ago, "Thou shalt
and more careful checks are made of be thy brother's keeper," has come to
each worker exposed, it appears to me pass.
i
DU P050314383
28 DISCUSSION
Ch a ir ma n Bo w d it c h : We have in vited to lead the discussion of Dr. Johns' paper a man who, though of not quite such long experience, has been a spe cialist in surgery and urology since 1925 and has had particular interest in the problems of lead workers.
He is a past president of the Ameri
can Urological Association and a wellknown writer on subjects of public health. He is consultant to a large num ber of industries and insurance com panies in New Jersey, and is medical director of the National Lead Company's plant in Perth Amboy, N. J. Dr. Wil liam C. Wilentz.
DISCUSSION
Dr . Wil l ia m C. Wil e n t z [National Lead Co., Perth Amboy, N. J.]: The subject of lead poisoning always arouses great interest wherever one travels. I am particularly delighted at the simple manner and calm reasoning that is evi dent in the paper we have just had the pleasure to hear. There is lacking that "Plumbo-Phobia" attitude which is so prevalent throughout our literature. This is very significant because it indicates a definite and wholesome trend away from the old days when the disease was more widespread and was responsible for great numbers of cases of temporary and permanent disability as well as deaths.
This situation was more or less recog nized by the leaders of industry hut the medical and allied professions were ig norant of the physiology and causes of this disease in addition to being unfa miliar with the methods of treatment. Today, although there are still many cases of temporary disability, there are fewer and fewer cases of permanent dis ability and rarely a death. This is a practical demonstration that sincere ef forts have been made and are being continued to diminish and eliminate this hazard. The results so far are grati fying.
The following are some comments which I shall take the liberty of making so as to clarify some of the important factors mentioned by Dr. Johns:
1. I wholeheartedly agree that only
one real type of treatment exists and that is prophylaxis. But at the same time, I know that until such time as prophylaxis is practiced properly and efficiently, our prob lem still remains to a great measure a matter of treating lead poisoning with a therapeutic regime directed towards (a) overcoming the intes tinal colic and discomfort, (b) cor recting the resultant anemia, (c) making the patient symptom-free with no disability remaining and (d) returning the patient to a re munerative position as soon as pos sible. 2. The question of changing jobs of individuals who are in this ex
posure is, of course, important and vital, hut I cannot help but state that in my experience, one is con stantly confronted with the prob lem of determining each employee's tolerance to dusts and fumes and
no matter how vigilant we may be, the occasional case arises which develops so acutely that it even astonishes us. One way to over come this problem may be by short ening the work day to six hours and putting in six days a week in stead of five. This has been rec ommended by Dr. Brockway of our organization. 3. We rarely find it necessary to use morphine or its derivatives to con trol pain. We use antispasmotics
jvpy
DU P050314384
IT 1|
TREATMENT OF LEAD POISONING
29
such as syntropan, trasentine with or without phenobarbital. We must not forget that the administration of calcium intravenously not only immobilizes the lead but also acts as an antispasmotic in its own way. 4. We utilize magnesium sulphate as the cathartic of choice. We find no objection to the use of phosphosoda; in this connection it might be said that we rarely find it necessary to employ enemas. 5. We encourage hospitalization in these cases as a rule because we know of no other place in which treatment can be administered around the dock. It is our opinion that this is the best method of get ting the quickest, most dramatic and permanent results. 6. We never prescribe iron, liver or calcium orally during the acute stage--which means while they are confined to the hospital--because we feel that the body will not be able to absorb these medications until the toxic effects of the lead have been overcome or are at a standstill and the metabolic pro cesses of the body have again be come adjusted. 7. We are opposed to returning these employees again to exposure. It has been our experience that these individuals will return with a more severe episode than the original attack. 8. We never employ deleading and wholeheartedly agree with Dr. Johns. Do the numerous methods advocated by deleading sponsors work? Kehoe has stated that "there are grave doubts whether or not the elimination of the toxic agent
can' be materially accelerated by artificial means," and he further feels that "this elimination can only be accomplished spontaneously over
a considerable length of time." Aub and his associates concluded that "complete deleading cannot be done." Oliver and many others have confirmed this finding. It is most interesting to note that prac tically all the advocates of delead ing admit that the procedure is dangerous and must only be at tempted under definite and specific circumstances. Johnstone noted that "this procedure (deleading) has been discarded due to the be lief that lead is excreted from the body by normal physiologic pro cesses." It is admitted by its ad vocates that rapid deleading is to be avoided and therefore it is ad visable to immobilize the lead in the bony structure during the acute episode. They also state that de leading is then advisable since the liberation of this stored lead is an obvious factor in the onset of toxic lead episodes during metabolic up sets. It is this latter statement which apparently is the principal argu ment used by the advocates of de leading. It almost sounds convinc ing were 'it not for the fact that in our experience in treating over 60-odd cases of lead intoxication and hundreds of absorption cases, not one case has presented itself where any such metabolic upset produced any liberation of stored lead to such a degree as to inca pacitate the individual. We admit that some conditions can produce some free circulating lead into the blood stream but the results are negligible and the individuals are symptom-free as far as lead is con cerned.
Belknap has stated that "after an absence from lead exposure of one to two years, lead intoxication prac tically never develops." Aub has
DUP050314385
30 DISCUSSION
stated that "from a theoretical standpoint, deleading is advisable-- but from a practical point of view, the answer is dependent on which procedure will advance most promptly to a recovery of health." We agree wholeheartedly with this declaration but one can hardly miss the implied suggestion in this state ment that perhaps deleading is not advisable from a practical point of view. And that is exactly what you and I are interested in. In other words, it just doesn't appear to be the method of choice.
It has also been stated that cir culatory lead may cause tissue dam age but stored lead in the bones produces no deleterious effects. If this is so, and so far as we know, it has been accepted by most men in this work, then what is the justi fication for employing a method of therapy which is acknowledged by its advocates as dangerous and un certain as to its ultimate results? We know that no method is avail able for the complete removal of lead from the body and further more can see no reason why this is desirable under the circumstances when it is well recognized and ac cepted that there is a normal lead metabolism governing the intake and output of lead from the body. It is our opinion that no remedy has been found to justify the dangers inherent in deleading. It is our con tention that it is more advisable not to employ deleading procedures in view of the fact that simple im mobilization of lead within the skeletal structures of the body is the most rapid and safe method of bringing about "a state of well being."
From our point of view, we do not advocate deleading because (a)
it is admitted as a dangerous pro cedure by its advocates, (b) pro longs hospitalization, (c) prolongs disability, and (d) results are un certain. On the other hand, calcium immobilization therapy is (a) sim ple and safe, (b) shortens hospi talization, (c) shortens length of disability, and (d) results are cer tain. 9. As to lead urines -- I simply would like to confess that the estimation of lead in the urine, stool and blood has never impressed me with the same importance as some men feel. The real information is to be ob tained from our blood counts, smears, and the clinical picture of the patient himself.
10. I agree with Dr. Johns about his thoughts relative to the non-employ ment of luetics in a lead exposure j ob -- we were forced to employ a number of these individuals dur ing the war and it is interesting that our experience was most satis factory-- perhaps we were just plain lucky -- I still feel that Dr. Johns is right. I would like to mention at this point that the fellow who worries me a great deal is the employee who gets drunk after each payday -- that's the man whose count gets thrown completely out of line -- anything could happen to him, but never does, for some reason or other.
It-is my belief that the treatment of lead poisoning is very simple and very satisfactory -- that we have at our dis posal definite and specific therapeutic procedures which if carried out properly will bring excellent results and will leave no disability of a permanent nature.
Ch a ir ma n Bo w d it c h : Again, there are so many here who may well wish to contribute to this discussion that I will
DUP050314386
I
TREATMENT OF LEAD POISONING
31
simply invite anyone who feels so in clined to speak his piece.
Dr . D. J. La u e r [Kettering Labora tory, University of Cincinnati, Cincin nati, Ohio]: Dr. Johns began his study of the treatment of lead poisoning the year I was bom. [Laughter] I was most interested to hear what he had to say. It sounded quite solid.
What I wanted to do this morning was to discuss Dr. Wilentz' opinions on deleading. I quite heartily agree with his thoughts. My agreement is based upon some observations we have made on individuals, with the idea of de termining whether or not we could "de lead" them. We have examined them very carefully, doing in addition X-ray examinations and complete blood studies. In a control period we have collected 24-hour samples of urine each day for a number of days. We have collected all the feces. We have analyzed duplicate samples of blood daily for their lead content and, of course, daily stippled cell counts have been made.
After the period of preliminary (con trol) observations, I started to admin ister ammonium chloride in divided doses at the rate of 6 gr. per day. In one case, I doubled the dose to 12 gr. a day in divided doses, and the patient
tolerated it. Then I stepped it up to 14 gr. a day. We were collecting all urine, feces and blood samples daily.
In addition, I determined the carbon dioxide combining power of the blood plasma of the individual, before we began ammonium chloride. I put him on a sodium-free diet of bananas, boiled rice and water, to make sure that we would remove the sodium ion as much as possible so as to produce an acidosis which is said to cause deleading.
Finally, after he had been on 14 gr. per day, he began to get a little short of breath, and developed other symp toms of acidosis. At that time his carbon
dioxide combining power was 37 vol umes percent, and I withdrew all medi cation and let him go back on his ordi nary diet, continuing to collect 24-hour samples of urine, feces and daily dupli cate blood samples and making daily stipple counts.
At the end of four days, dioxide com bining power had returned to 52 vol umes percent, or normal.
In the study of products of the urine, feces and blood, the analytical data on the blood and excreta demonstrate that there was no deleading and no storage of lead. The experimental period re mained like the control period with re spect to lead output.
I want to continue further observa tions on this because the number of cases is somewhat limited. We have studied other agents that are said to promote deleading, such as potassium iodide, and so on, and we want to study them further. We have failed to find evidence of deleading under the influ ence of these agents.
I hope to say a little something on BAL tomorrow. We have done some studies on that.
Ch a ir ma n , Bo w d it c h : All of this augurs well for a spirited debate to morrow morning. Who is the next con tributor to this discussion?
Dr . Wm. G. Wo o d [National Lead Co., St. Louis, Mo.]: I wondered why the basophilic aggregation has not been mentioned in the treatment of these two cases. Have you used the basophilic test?
Dr . La u e r : I have used the basophilic aggregation test in the past. I have not used it for some years. We just merely used the stipple count, among other things.
Mr . G. C. Wa l t e r s [National Lead Co., Chicago, 111.]: He asked about the basophilic aggregation count. We used the basophilic aggregation count for
DUP050314387
32 DISCUSSION
about four years, along with the stippled cell count. While there was rather a constant correlation, the graph line would separate at times. The reason we abandoned it was because of the various staining elements that threw us off with a light field scope. With a dark field scope it might be different.
We found, even in normal individuals, taking the same counts, in a week's time they would differ from the day the stain was made. There may be a better stain. We used those recommended by McCord and several that were recommended in Industrial Medicine, but we could never find constantly good counts and as re liable as the stippled cell count. It would cause a great deal of argument on both sides.
Ch a ir ma n Bo w d it c h : Would you care to comment on that, Dr. Mayers?
Dr . Ma y R. May er s [New York State Department of Labor, New York N. Y.]: I have never worked with basophilic aggregations, so I would not be able to say from my own experience. But it is my feeling that, when you are dealing with the blood picture in lead poison ing, it is the very same thing as dealing with any other blood dyserasia in terms of the technics used for interpreting the blood picture. It seems to me the sim pler thing to do is to take the regular smear and stain it and examine it for stippled cells along with all other ab normal cells as one does with every other blood disease.
I would like to stress very much the fact that, in our experience, stippling per se is not too important. In a par ticular smear it may be very unimpor tant The fact that, with a very slight drop in the hemoglobin and the red cell count, you can get nucleated red cells, or marked changes in size and shape of red cells, can be much more significant in a particular case than the stipple count.
I do not like to feel that we should stress stippling too much in general. That is why I have not even tried McCord's basophilic aggregation test It is a procedure which is out of line with the general diagnostic approach to blood diseases. This approach should be just the same in lead poisoning as in any other blood disease, in my opinion.
Ch a ir ma n Bo w d it c h : Ho w about you, Dr. Johnstone; would you care to enter into this discussion?
Dr . Ru t h e r f o r d T. Jo h n s t o n e [Consultant in Occupational Medicine and Industrial Hygiene, Los Angeles, Calif.]: I do not know of any disease, occupational or otherwise, about which so much nonsense has been written as lead poisoning. I particularly object to the carry-over from the older literature which we constantly see repeated by writers today.
I have in mind a monograph on lead poisoning which was fairly recently published. This monograph quotes all of the available information about lead poisoning but fails to discriminate be tween statements which have been proven to be scientific and those which are merely conjectural. It is very con fusing.
My experience with lead poisoning is different from most of your physicians here who supervise the medical care in large plants. You probably see very few cases of lead poisoning and because of that there is a growing tendency to be lieve that lead poisoning is on the de cline. I disagree with such an assump tion. In the area where I practice we have a great number of reclaiming plants, smelting plants and a large num ber of small companies who manufac ture batteries. It is with these small companies that we have a fairly high frequency of lead poisoning. Of course, we occasionally see individuals with lead
i
DU P050314388
TREATMENT OF LEAD POISONING
33
m
poisoning who work in larger com this fellow got was spinal taps to relieve panies where they should have better his pressure. After he was discharged
hygiene.
1 followed him for a period of four or
As far as - symptoms are concerned, five years. On one occasion he had a
almost all of these cases are mild. In blood stream infection. At that time we
twelve years I have seen but one case were able to determine the lead in the
of lead encephalitis, and only two cases blood and urine which revealed no in
of wrist drop. The remaining cases, as crease above the normal. In other words,
I have said, are mild with an occasional we saw no release of lead during his
moderately severe case. There are sev acute illness. The same man was seen
eral reasons for this.
because of a severe pneumonia, and at
: In the first place, the average work that time also he had no increase of lead
man is conscious of lead hazards and he in his blood or urine.
is particularly aware of the fact that It is my opinion that the simpler we
stomach-ache may be a symptom of lead attack this problem the better, and
poisoning. Therefore, today these men when we are writing about it in the
report to a doctor fairly early in their literature we should cut out a lot of the
disease. Also, the representatives of nonsense about the sequelae of lead
labor unions within these plants are poisoning.
diligent in seeing to it that the workers
Dr . Al b e r t S. Gr a y [Director,
get early medical care.
Bureau of Industrial Hygiene, Connec
As far as the treatment of lead poison ticut Department of Health, Hartford,
ing is concerned, we actually do not Conn.]: I agree entirely with Dr. John
treat lead poisoning per se. We with stone that it is the small plants where
draw the man from exposure, and never we get these cases.
give him morphine for his colic or pain, I would like to ask Dr. Johnstone, or
nor do we use any other antispasmodics anybody who is here, if they have any
except calcium. We do not find it nec plan for industry to use as a routine
essary to hospitalize these patients. I plan. As an administrator of industrial
have not hospitalized a case of lead hygiene activities, we try not to lean
poisoning for a good many years. We down too heavily on industry but to
do treat them for their anemia, after require those things that we realize are
the initial calcium therapy.
best for the industry and the worker.
Just before coming to Chicago I One of the things that we have to do,
looked over our record sheet to deter particularly in the smaller and the
mine the average length of disability of medium-sized industries, is to suggest
our cases. This may startle you, but some routine course of procedure.
our average period of disability for Most of the plants in Connecticut, and
these men is three weeks. At the end I suspect in many of the states, are ad
of that time we send them back into an ministered to by physicians. But you
occupation where there is no lead haz know that they do not get paid for look
ard. There have been some cases with ing over the plant, and they are very
a longer period of disability, but as I busy men, usually men in general
say, the average is three weeks.
practice.
We had one case of lead encephalitis, We find, for instance, where we must
as I previously mentioned. He was have some routine procedure, where the
hospitalized, of course. This was a num men should be examined and certain
ber of years ago. The only treatment needed work done--I am not going to
DU P050314389
J 'V
. ....
34 DISCUSSION
say just what we have them do, because I want some of you to tell me what we ought to have them do--it is necessary to follow up whatever procedure is re quired continually. We .find frequently that the plant has not sent the men to the doctor. We go to the doctor, and he says, "The plant did not send them to me." The plant says, "Well, the doc tor didn't ask for them." So, we con tinually have to follow through to see that the necessary work is done.
Then, when the work is done and a report is provided there is frequently no attempt to follow through and apply the results of the examination construc tively. We look it over, go to see the doctor and if some results are high, may suggest that some of the men should be transferred, and he is usually agree able.
We go to the plant if results are high to check up on control. There does not seem to be very much interest displayed by the doctor on call in the small and medium-sized plants to follow through. He just does the examination as a part of his, if I may say so, on-call job, and there the matter rests.
I would like to hear from some of you gentlemen who have some plan which can be given to the plants re specting the procedure they should fol low. Should these men be examined once a month, once in three months? Should they have a physical examina tion before they are exposed to lead, one or two examinations, to establish a base line for their blood examination or their stipple cells, or aggregation?
I think these matters are very im portant. You folks in the lead industry undoubtedly, at times, object to what we State people want. If we knew what you think is desirable, and you knew what we feel is necessary, we could get together on something that I think we would both feel was more constructive.
We examine the environment of lead exposure very carefully. We have good engineers, doctors and chemists. We try to control exposure to lead. We have found, as a rule, that industry accepts constructive recommendations for such control but things will happen even on the best engineered job if you do not follow through.
A plant that has a good vacuum cleaning machine and a poor foreman will still use a broom. A worker will stick his head under the hood, and he will refuse to wear his respirator or leave it off on certain occasional jobs he has to do.
On many occasions, you know that the best engineering will not permit you to sleep soundly if you do not follow through.
Dr . Jo h n s t o n e : I want to answer Dr. Gray's one question, the first ques tion he asked.
I do not know how it is in the rest of the country, but out in our part of the country a good many of the plants sup ply the plant manager with the normal stipple count, then the employees at in tervals are sent to a laboratory and when the laboratory report comes back the plant manager takes it upon hitiiself to decide whether this man has too much lead in him or not. [Laughter]
The second big fault is that a great many plants hire a two-dollar doctor, and they get a two-dollar examination. They will send employees around the corner to a physician who has never been in the plant. He gives them a brief and cursory examination and then re turns them to their work. The Lead In dustries Association should encourage their members to employ experienced physicians and to pay a worthwhile fee for the examination of their men.
I do not know how far the Lead In dustries Association is going, to educate the little man. As I look through the list
!
DUP050314390
5
TREATMENT OF LEAD POISONING
35
of this membership it is apparent that Our routine is, of course, that every
most of your members employ physi man receives a pre-employment exami
cians thoroughly cognizant of this prob nation, including a complete blood pic
lem, but it is the little industries that do ture and urinalysis. Then, every man
not appreciate the problem, and that is who is exposed to a lead hazard is seen
where the big job in education lies. The by me once each month. I see groups of
second job, of all things, is to educate about 15 or 20 men each morning at
the doctor.
the plant. Every man in a lead exposure
Ch a ir ma n Bo w d it c h : I see Dr. Johns is smeared monthly. He is seen by me
is itching to make a further comment and talked to, with a general inspection
but, before he does, I want to add to and questioning. We seem to get along
what Dr. Johnstone has just said.
very well on that basis. We are doing a
I shall always remember, some years number of lead urines, also. But I have
ago, talking with the physician of a relied, in the greater part of my ex
large plant of a very large company up perience, on the inspection and examin
in my former part of the world, a plant ing of the men, and the blood smears.
which had a very definite lead hazard. Each man in the plant is examined
He said to me, "Mr. Bowditch, how yearly. He gets a complete physical ex
about this urine sulfate test for lead amination. I examine about five or six
poisoning?"
men in an hour and one-half.
Now, Dr. Johns, would you like to add To answer this gentleman, our routine
something?
is: I visit the plant twice a week. Every
Dr . Jo h n s : I entered the lead field man in a lead exposure is seen by me
in the days when, if I visited a plant to monthly. I am the one to say whether
call on the superintendent to talk over a man's employment is changed, and I
some matters, he would look up and have had some difficulties in that matter,
down the hall to see if anybody had though, I think, as I said before in the
seen me come into his office. [Laughter] paper, that my insistence that a man's
Also, the stipple counts and anything employment be changed has stirred them
else which releated to lead intoxication up on their engineering ends.
were kept in the superintendent's safe. I do want to say, and I still believe
Nobody saw' them but the doctor and that we are derelict in our dust counts
him, and then, later on, the safety man. in the plants. They are not made fre
But I have gone along for 25 years quently enough. 1 think, if there is one
in this phase, and I can say that man thing that we must do in the lead indus
agement has gone along with me. I try, it is to sell management on the fact
think, by far the greater part of the that we should take more dust counts.
credit for so few lead poisoning cases, The men are changed in their employ
in my experience, has been due a great ment, and I see that they are changed.
deal to the engineering and good house We have a record of every man who I
keeping and the inspection of the plant advise that his work be changed, and I
by the physician.
check. If he has been put back on any
It is true there are small plants in regular work, he must come in, and I
which a physician does not visit, only 0. K. his going back to his old employ
on call, but, in my field, I visit each one ment. That is the regime that we follow
of my plants twice weekly and spend in the three plants that I take care of.
about an hour and one-half to two As far as seeing lead poisoning, I can
hours at each plant,
say truthfully, in the last eight years we
DUP050314391
36 DISCUSSION
have had no cases that have gone before red cells.
the Industrial Board in the State of
Dr . Gr a y : It runs about the same
Indiana from the three plants that I with the aggregations.
take care of. I think we are doing a job
Dr . Jo h n s : We do not do the aggre
there, but it has been in cooperation gations ; we do the stipple count. I think
with plant management and the doctors. there is nothing more important than to
I would estimate, roughly, the num bring your man in periodically, once a
ber of men who are exposed to a lead month, and talk to him and find out
hazard in all three plants, at about 500. what he is doing.
Dr . Gr a y : I would like to say, I think
Dr . Gr a y : I think that is very im
some time some clever man, who has portant.
been at the job as long as you have
Dr . Jo h n : I think there is no phase
i might tell us the differentiation, the di of medicine where you have to take the
viding line between lead absorption and man's history as much as you do in lead
lead intoxication.
absorption or lead poisoning, because
We talk about lead absorption, and what he tells you is pretty nearly what
somebody says, "I don't treat any cases is happening.
of lead poisoning. Some of the fellows Dr . Gr a y : That is unfortunate in the
have colic." And somebody else says small plant. You usually cannot get that.
they don't treat any cases of lead poi
Dr . Jo h n s : That is right. I will agree
soning, "but a fellow isn't feeling well. with you.
Has he got lead poisoning?"
Mr . Wa l t e r s : Some years back we
I do not think that we are very clear had to make the stippled cell counts
in our delineation between lead absorp twice weekly, in order to keep ahead of
tion and lead poisoning. As for myself the men, but it was in a very bad spot
lead poisoning is sufficient absorption and has since been removed. We would
to produce signs and symptoms, but never have been able to keep ahead of
many apparently do not subscribe to them if we had made the counts only
this definition.
once a month.
Dr . Jo h n s : When any man comes to
Dr . Jo h n s : We do them routinely,
me and, when I question him, he tells but every man exposed to a lead hazard
me that periodically he has intestinal will be smeared once a month.
cramps, I regard him as a case of lead
Mr . Wa l t e r s : Some of the people
poisoning. But for lead absorption, I here might be from small plants and I
use this as my threshold: If a man has would like to say that we should not
over 1,200 stipple cells per million red belittle any one technique that they may
cells, his work is changed immediately. use. For instance, some plant might
I grant you that, in your textbooks, employ only one technique, where a
they say 300 or 400 is permissible but, larger plant might employ five or six
after years in this, I have seen no cases very elaborate techniques, including
where we got into any trouble about it, tests for lead in the feces, urine, blood
or the man has been ill where he has levels, etc. So, that the small plant
not been permitted to go along over should not feel that, because their par
1,200. In our stipple count we call that ticular technique is not complete within
0.12, and his work is changed, if he goes itself, to assume an attitude that "Oh,
over that.
well, we will just forget it entirely,"
Dr . Gr a y : Your stipple is 0.12?
because one technique is a tool and it
Dr . Jo h n s : That is 1,200 per million should not be dropped. It should be
DUP050314392
TREATMENT OF LEAD POISONING
37
built onto and I believe progressive Johnstone about hospitalization. We
small plants will build to it.
have talked about this before. We hos
Da. Jo h n s : I have been very for pitalize our cases of lead intoxication;
tunate in having the same man examine I mean the really sick fellows. It varies
my smears for 22 years. That, to me, as to degree. The doctor says that we
means a great deal. When I send smears must see sicker patients. I am willing
to the hospital, I am somewhat skep to take that as the answer, because I
tical. Our man finds stipple cells and think we hospitalize 65 to 70 percent of
the hospital does not find them. I think our cases, and we are delighted to do it,
that is because they do not see very because, you know, it is the one place
many slides with stipple counts, but, where you can really do a job. You
fortunately, I have had our technician know they are going to get the medica
for 22 years, and he examines about tion. You certainly cannot give them
6,000 slides a year.
one shot a day, and expect to clear up
Dr . Wil l ia m C. Wil e n t z [National the case quickly or satisfactorily.
Lead Co., Perth Amboy, N. J.] I would I just send them to the hospital. Many
like to comment upon what Dr. Mayers of these men I was unable to send be
said before. She is taking no chances cause they would not go. It is a long
when she talks about taking the whole procedure if you do not hospitalize, and
picture as the horizon. Do not worry I like hospitalization because of effi
about the stipples or do not pay too ciency.
much attention to it is not quite fair
Dr . Jo h n s t o n e: Ho w long did you
a remark.
say the disability is. Doctor?
Dr. Mayers, I think that, in lead, stip
Dr . Wil e n t z: An average of three
pling is so attached to the problem, to weeks. Our ambulatory cases are usually
the poison, you cannot belittle it, and I disabled about 15 days; on our hospital
know that you do not, but I do not want cases, the average disability is about 30
anybody to get the idea that you feel days. We are talking here of lost time
that way about it.
from work
^
It is so intimately attached, if you I would like to mike another remark.
do not pay attention to it, you may be I said something about it before. It
lost. It is a big thing. Lead and stip seems to me that we should not confine
pling go hand in hand, so much so that, the information that we get from our
when you have your cases in a hospital, work just to periodicals that go to you
what do you find? You find the tech and myself. I think that is one of the
nicians in the hospital do not know what mistakes that we make. I think the in
a stipple cell looks like. How often do formation that we have, that we get,
they see it? I don't know, but I do ought to be placed in periodicals that
know one thing about it, when we send have a large circulation, so that the
people with lead, they learn on our other fellow who may occasionally meet
patients. They don't know what stippling these cases but who does not know lead
looks like. We have, of course, our poisoning when he sees it, will get some
technicians who are trained for it. But, of this information.
so far as I am concerned, stippling is After all, we are talking to each other,
part and parcel of the entire picture and I do not know how much good it does,
it is terribly important. You have to but it ought to do us a lot of good.
learn for yourself how important it is. There is a limit as to how much good
I would like to say something to Dr. it can do. Many of you people could
DU P050314393
38 DISCUSSION
come up and say what we have been ears, because in some meetings where
saying this morning, with just as much I have gotten up and ventured even to
authority because you have equal ex mention the word "stippled cell" or even
perience.
such a thing as a lead line, I have often
I would like to see a more widespread been properly put in my place.
dissemination of this information, in
In that connection, I recall at the
stead of confirming it just to you and Boston meeting of the A.M.A., when
to me.
this whole subject was explored, we had
Dr . El s t o n L. Be l k n a p [Globe- a visiting physician from England--
Union, Inc., Milwaukee, Wis.j: I hope I believe his name was Dr. Lane--whose
to say a little more this afternoon and first comment was, "I have listened all
in a little more connected fashion, but morning and I haven't heard anybody
I felt I could not miss this opportunity mention the subject of a lead line."
i of congratulating two men who are Indeed the papers up to that time had
i physicians and clinicians on an excellent been largely laboratory and non-clinical. grasp of the subject, namely. Dr. Johns In regard to stipple cells, I received
and Dr. Wilentz. It is not because their a letter from the director of probably
ideas and my ideas are exactly alike. one of the largest storage battery com
We have minor differences. But what panies in England, from the assistant
impressed me was the opinion of men medical officer, Dr. Scott, who had writ
who know their way around in the field ten over here asking our practical pro
of industrial medicine and who have cedure in controlling lead absorption
seen many cases of lead poisoning, se and lead intoxication in storage battery
vere cases in the old days, less severe workers so that they are able to keep
now.
healthy and at work. He was wondering
I did not want to let the opportunity if, perhaps, they were getting behind the
.! pass without paying my deep respects times over there in England and not
to both of them, and also to the other using up-to-date laboratory work.
men who were the discussants, such as
In reply to my letter he said that he
Dr. Johnstone, who also has had a great has approximately 800 men under his
deal of practical experience.
supervision. He says, "On the average,
Sometimes I have been so discouraged we may transfer, temporarily or perma
in a meeting of this kind that I did not nently, ten to fifteen men a year on the
say anything. [Laughter] I would see grounds of sub-clinical plumbism." He
men get up who were not physicians, does not let them go to the point of
and some men who were physicians-- disabling lead intoxication, however.
which was, perhaps worse [laughter]
In regard to this subject of stippled
--and make comments showing that they cells, which he approves of, as our
had no clinical grasp of the subject of speakers have today, and which with
lead poisoning. After all, there is such hemoglobin study, they use largely in
a thing as lead poisoning. Men do be controlling their problem, he says,
come ill and sick with lead absorption. "Having studied your and Dr. Fairhall's
We say they have lead intoxication. views, I feel that our present methods
Fortunately, lead poisoning or true lead are very much in agreement and that
intoxication is much rarer now than it there is no good reason for changing
used to be.
them."
The emphasis that we have heard Whenever I have talked to men who
today, on stipple cells, is balm to my have been in an industry where men
DUP05 0314394
TREATMENT OF LEAD POISONING
.
39
work all day long, with heavy amounts of lead exposure, I note that they rely heavily on the counting of stipple cells. They rely, also, on frequent examina tions, such as have been stressed by Dr. Johns today.
There is no machine, protective equip ment, or even an excellent foreman that c,,an always control a situation so that a man may not suddenly have an ex cessive amount of lead absorption.
There is the human factor which is un predictable, and that must be controlled by a well founded system of medical control.
Nineteen years ago when I was called to become consultant medical director of the storage battery concern where I am now at the home plant, and which has eight or nine plants over the coun try, we had in our home plant 20 men per hundred disabled every year from lead intoxication.
We gradually reduced that by trans ferring men, by engineering protection and by conferences with management, who were very anxious for several rea sons to reduce lead exposure. For the past twelve years, we have had no cases of disabling lead absorption or lead intoxication. By disability, agreeing with Dr. Johns, I mean that a man is actually sick. If he has a pain in his bell)', constipation, anemia, and a cor responding rising stipple cell curve with evidence of lead absorption shown by lead line and perhaps by lead in the urine, then I believe he is a case of lead poisoning. Until recently, we have had no such case for twelve years.
We did have lead absorption but not a case of disabling lead intoxication. We never, in fact, were without some man who had considerable lead absorption as shown by lead line and stippled cell elevation figuring on the criterion of around 20, 30 per 50 fields. This I re gard as the dangerous level.
I think, probably, Dr. Johns' figure of 12 is safer; that is, he says 1,200 per million which, when you divide that by 100, gives 12 per 50 fields. There are about 10,000 red cells per 50 fields. 1 think, perhaps, management felt that there was no such thing as lead poison ing or even lead absorption at the home plant for some reason.
We had to use respirators at certain jobs. There were certain operations where both the engineers and I had recommended changes, such as remelt ing in the plant where scrap is dumped on the floor and then shoveled into a kettle. But it took a real case to awaken everybody.
About a month and one-half ago, I observed that one man was showing stipple cells 20 per 50 fields, when he also began to show a lead line. I re marked on the matter not only to the foreman but to the man himself. I have always found it most advisable to take the worker into my confidence and say, "Joe, you have a lead line. You are ab sorbing some lead. It isn't lead poison ing now, but, if you are not careful and if you do not cooperate with your res pirator, you may have a terrific belly ache."
He said he would cooperate, but he didn't. Management wanted to keep him. It was a dirty job; a remelt job is usually the dirtiest place in the factory, and he was willing to work. He was making good money. So, for purposes of production, they kept him.
About two weeks ago I wrote, a special comment to the superintendent asking that he be moved. About three days later, he suddenly did not show up for work. His stipple cells were running 20 to 24; and as I said, he had a faint lead, line. He was feeling fine the last time I had seen him. The day before he left work, his stipple cells were 50. I took the technician and we went out to see
1
DU P050314395
1
40 DISCUSSION
the patient. We had been told by a lay man at the plant that probably he was out attending to some "special pri vate work," but, having followed the patient personally, I felt he was not a man who would complain unless he really had something the matter with him.
Knowing the warning signal of that stipple cell count, that sudden rise, 20, 24, 50, I thought, "Here is where our record is broken."
When I got out there, I found him sitting up, hunched over, and clutching his abdomen. He was a man who did not complain much. You have to know these individuals to know their reaction to pain. I said, "Joe, how did- you sleep last night?"
He said, "I didn't sleep." "What is the trouble?" "My bowels haven't moved for two days. I was up every hour, trying to have my bowels move, but I couldn't do it. I took salts. I took Ex-Lax. I took everything that I or my friends had." His hemoglobin had previously been dropping very slowly, 90, 85, 80--and was now below 80, which is a danger sign----was 78--and his stipple cells were 75. So I said, "Well, just get in the car with us. We are taking you to the hospital." At the hospital we gave the same treatment that has been outlined, cal cium gluconate intravenously, to relieve the spasm, and then a saline cathartic, when the spasm was relieved to empty the bowels. We also aided that with an enema, and we had very good results. When we opened the channel, as it were, all the different cathartics suddenly be gan to work [laughter] and he was very grateful. [Laughter] We only had to give the one calcium gluconate intra venously.
I would call his case a relatively mild
case because, usually, these cases do not come under control for a day or two,
but they do get relief with calcium glu conate intravenously every four hours. I
believe that is fully as good if not better
than morphine. I agree with Dr. John
stone on that, again.
We knew we had some warning; we
knew what was coming. The only thing was that I was not tough enough with our management.
The other day I read an article by one of the medical directors of a large corporation, and he was describing the qualities of a good medical director. He said, of course, such a physician had to be diligent and a good student, but he had to be a damn good fighter, and I think that is so, even with the
best of management.
'
My particular company has really leaned over backwards to give me every cooperation. When I first went there,
they said, "Hitch your wagon to a star. We may not be able to gear our pro
duction immediately to the changes you
want, but we will change as soon as we can," and they have done that consis tently. Our medical program has been keyed into that.
That gives you a practical instance, though some of you, perhaps, are not familiar with how the physician works these problems out, how we study a case and often predict a case and how we de
cide that it is a case of lead poisoning, see that compensation is given, and then have the man return to work promptly.
This man is not going back to work with lead immediately. He has no great anemia, however, and I feel that, if con ditions are right, he can do some work with lead again if properly protected, but I certainly would not put him on the remelt kettle again.
Thank you.
DU P050314396
MONDAY AFTERNOON SESSION
November 15. 1948
Ch a ir ma n Bo w d it c h .: Our first speaker this afternoon, as compared with some of those whom we heard this morning, is a relative newcomer to in dustrial medicine. Following periods of private practice and general medicine in the Army, he had his first industrial
work in the Plastics Division of the duPont Company at Arlington, New Jersey, and is now medical director of the Electric Storage Battery Company in Philadelphia. Dr. F. B. Lanahan will speak on Preventive Medical Armor for the Lead Industry.
Bl PREVENTIVE MEDICAL ARMOR FOR THE LEAD INDUSTRY
|r By F. B. LANAHAN, M.D. Medical Director, Electric Storage Battery Co., Philadelphia, Pa.
I should like to preface my prepared presentation by a few remarks which I am stimulated to make in light of the tone of the discussions which preceded the luncheon period.
My relative youth and brevity of ex perience in industrial medicine prompts me to make the obvious remark, that my position here at this microphone draws heavily on the courage of my convictions.
At Philadelphia, the Electric Storage Battery Company has two plants. We have, to our conviction, over 2,000 people who have a lead exposure of some extent. We have two physicians who are full time and two part-time physicians.
During this past year, with our pres ent program, grossly revamped from what previously existed, we have cre ated an atmosphere and a facility which have prompted our employees to make easy use of our presence during the eight hours of their day-shift.
It is on the basis of that facility, not on the basis of our laboratory studies, that we have seen too many cases of lead intoxication, not severe intoxica tion, yet lead intoxication.
They have not come to us commonly on the basis of our stipple cell-hemo globin studies. We are aware of them
because these men, to our great good fortune, have made use of our constant presence among them. When we are alarmed by high stipple cells and at tempt to substantiate the lead factor by analytical blood and urine studies, most commonly, we find ourselves in some diagnostic problem other than lead.
In passing, briefly, I would like to mention one disorder that impresses us most deeply, and I am sure exists in all of your plants. It is the problem of the Mediterranean type anemia, which we see in a number of our Italians. That, strikingly, will raise stipple counts.
The other cases that have come to us primarily through our blood studies have been a multiple myeloma and liver carcinoma.
Inasmuch as it takes two full-time physicians and two part-time physicians to give what we feel is a reasonable type of industrial medicine, I would like to join hands with Dr. Gray and say that, with the $2-a-visit type of industrial medicine, you are not getting even $2 worth; it is impossible.
41
DU P050314397
42 LANAHAN
With that preface to describe the en know which horse to look for. When
vironment that my presence here repre analytical methods were resorted to, it
sents, I should like to present this for was for specific diagnostic purposes;
your consideration.
indeed, too late with too little for pre
Purges are known chiefly within the ventive medical aims.
walls of Communistic domination. Ul
We found the use of hemoglobin de
cerations on the body of nations in terminations, stippled cell counts and
flicted by extended arms of the Marxian physical examinations established as the
Octopus are excised by healing Chris medical methods of choice, and we fol
tian action. Curative or destructive lowed them, lacking knowledge of better
are today's searching forces.
means. These revealed established dis
Curative and constructive are the orders of structure and function. Lead
aims of The Electric Storage Battery in air determinations were in use. These
Medical Division in Philadelphia. Pre necessarily were brief and infrequent
ventive medical principles form the when related to the individual's total
foundation of the Division's reorgani work exposure. They could not reflect
zation instituted one year ago. Assess negligent working habits. Hygiene in
ment of all established procedures was structions fell on torpid health attitudes
instituted. On the body of the Pre as on the well known duck's back. The
ventive Medical Program, lead control knowledge that these methods and work
methods hung like a withered arm, help ing habits were widely existent in the
less to prevent illness.
lead industry gave small and unwanted
Though harsh is our criticism of es consolation.
tablished methods, sincere is our ad
To establish preventive medical prin
miration for investigators who applied ciples a wide chasm appeared before us.
these methods in the light of past It was the void between lead exposure
knowledge. It is believed these same and toxic lead absorption, between re
investigators with their proven abilities sults of spot air samples and actual lead
will, with the stronger light of present absorption during the total work period,
knowledge, lead the industry forward influenced by 'negligent working habits.
into the arena of preventive medicine. It was the darkness obscuring failing
As our present control methods are tissue defenses of the worker whose pro
known to be common to the lead in longed exposure to generally safe en
dustry in general, our convictions and vironment could be causing insidious
corrective measures are presented here damage. A bridge was needed to span
for general consideration.
the chasm and give firm footing for the
Entering the field of lead toxicology, preservation of health.
we carried deep rooted convictions con
Nature is found to give the bridge.
cerning the soundness of preventive An instrument of the Divine Scientist,
medical principles and the wealth of human metabolism, spans the chasm.
benefit they hold for industry. We The man on the j ob is the best impinger
looked for methods of control indicative and precipitator of the lead to which he
of levels of lead absorption within limits is exposed. His period of collective
compatible with health. Methods in use samples represents his total working
were found to be non-specific of lead period. His faulty working habits are
absorption and demonstrative of exist reflected. These facts are recorded in
ing tissue damage. Invariably, the analytical studies of his excretions.
horse was out of the barn. Nor did we The direct relationship between at-
DUP050314398
PREVENTIVE MEDICAL ARMOR
43
mospheric and oral lead contamination technical errors. Yet, it is practical with
and lead excretion in Hood, urine and in the abilities of all of us who are de
feces has been revealed by the meticu termined to strive for the highest plane
lous studies of Dr. Robert Kehoe and of medicine and hygiene.
his associates at the Kettering Labora
It is our purpose to use this method
tory. Ranges of excretions related to for the regular observation of our work
casual and to occupational exposures men. Relying generally on spot urine
and compatible with health have been samples, we will study larger volumes
indicated by them. Criteria for dealing or frequent spot samples of urine in the
with workmen on the planes of their event a single spot result suggests an
lead absorption and excretion have been increasing range of excretion. When
established by them on the basis of long high range of excretion is indicated by
experience.
the additional studies, samples of blood
The use of these analytical studies and urine will be obtained for more
are known to all of us. Essentially, our precise analysis.
application of them has been for diag
As the rapid method is known to con
nostic purposes. When we have been fuse bismuth with lead, it will be routine
alarmed by anemia, high stipple count to inquire of any medication being taken
or clinical evidences of disorders which by the workers. The incidence of bis
could mean lead intoxication, we have muth in the routine studies is expected
resorted to them.
to be small. When high values are ob
Few of us have applied the analytical tained, the longer method of analysis
measures as preventive controls. Known will be employed, thus excluding bis
outstanding exceptions have been the muth or any other metal than lead.
programs developed by Dr. Hamlin in To minimize contamination of the
the American Brake Shoe Corp. and in samples by work clothing it is planned
the Ethyl Corp., but to a lesser degree in to collect the samples before work
certain other industries, by Dr. Kehoe. clothes are worn or after showers. Col
The majority of us have placed the bur lection of samples at the beginning of a
den of our negligence on the complexity shift is likely to exclude high concentra
of analytical procedures.
tions or dilutions of the samples.
We can no longer afford to retain our Equipment necessary to apply the use
present methods in the guise of lead of the rapid method is approximated to
control. We must recognize them for cost $3,000. As the analyses must be
their inadequacy as preventive measures made in an atmosphere free of lead, the
and resort to them in their true function cost of air conditioning a room in the
as secondary diagnostic tools. This production area would have to be ac
change is forced upon us by the present counted. A 500 sq, ft. area is considered
availability of a simplified, rapid ana adequate for the analytical laboratory.
lytical method to determine lead in urine A technician working under the super
spot samples. This is the procedure de vision of a chemist can make 30 to 40
scribed by Dr. Jacob Cholak and his determinations daily. To avoid phos
associates at the Kettering Laboratory in phate precipitation, the samples must be
the January, 1948 number of the Jour analyzed as soon as possible after they
nal of Industrial Hygiene and Toxi are voided and always within 24 hours.
cology.
A general survey of the plant by this
Though rapid, the method demands method will establish the mean excretory
studied care to avoid contamination and levels of the men working in specific
i
DU P050314399
44 DISCUSSION
areas. On this basis a schedule of inter val studies can be established. Attending to necessary precision, the ease with which the analyses can be made will allow for a flexibility of the scheduled studies to check variations in production methods and environmental factors.
This routine applicable to group studies will be applied to individual workmen whose excretory levels fail to conform to mean group values.
Air analyses will be used to accom plish its present purpose but it will gain a firmer footing of usefulness in dis tinguishing the atmospheric factor of contamination in suspected environ ments. The suspicion will have been cast by high mean values among the work men of the particular area.
Should our facilities and the person nel permit us to develop our own analy ses by the longer methods, as has been shown to be practical by Dr. Hamlin and Mr. Weber of the American Brake Shoe Corp., the combined equipment is judged to cost about $10,000.
As in the general field of industrial medicine, small plants with limited bud
gets can share the benefit of this quality of medicine and hygiene by pooling their needs and spreading their expenses through the use of centrally located in dustrial clinics. The qualification of such existing clinics for our particular need or the stimulus to develop them is a fertile field of activity for the Lead In dustries Association.
As we progress toward the accomplish ment of our program we do so with the stimulating conviction that our efforts will establish a regimen of preventive medical control which will -- Keep men fit for their jobs and jobs fit for men.
Ch a ir ma n Bo w d it c h : The principal discussion of Dr. Lanahan's paper will he by a man from whom you heard this morning. He is a specialist in industrial medicine and toxicology of many years' standing, a member of the Committee on Lead Poisoning of the American Public Health Association, associate pro fessor of medicine at Marquette Uni versity and consultant to Globe-Union, Inc. and to a number of other industries and insurance companies. Dr. Elston L. Belknap.
DISCUSSION
Dr . El s t o n L. Be l k n a p [GlobeUnion, Inc., Milwaukee, Wis.]: Mr. Bowditch, members of the Lead Indus tries Association, friends and co-work ers: I believe that Dr. Lanahan is to be congratulated for his convictions and his determination to approach this in a very basic way.
I wonder, and perhaps he can answer me shortly, whether his method of urine examination, spot samples and group samples, will replace the time-honored method of physical examinations for lead lines, blood studies for hemoglobin, types of red cells, stipple cells and his tory, or whether it is used to supple ment it.
1 am interested to know how soon, also, he thought he could recheck his workers with this method. For instance, if he has 2,000 workers and 40 can be done a day, it would take about fifty days before he could get back and re check a worker. Perhaps he will supple ment that with the other usual forms of treatment in the meantime.
My experience with lead in the urine has been to get it, if possible, about twice a year on a lead worker, prefer ably a twenty-four hour urine that has been collected at home, away from the plant. It is then studied by the Fairhall modification of the chromate method, which, though it takes three or four
DUP050314400
PREVENTIVE MEDICAL ARMOR
45
days, we have felt from experience has been the most fundamentally safe pro cedure because it is primarily an ana lytical chemical method.
I understand that Dr. Fairhall has modified this so that the analysis can be done in a matter of hours. This, I be lieve, will answer the objections to this method. '
It seems to me the question comes
back to this. When you have done an examination of lead in the urine, what do you have? Do you have a diagnosis of lead poisoning or do you have a diagnosis of lead absorption?
Certainly, the Public Health Commit tee, of which Dr. Kehoe is chairman, specifically said that no one laboratory finding made the diagnosis of lead poi soning and, as already has been brought out here by a number of speakers, in cluding Dr. Mayers, whom I have al ways admired primarily for her ability as a clinician, that one must view the patient as a whole. No one should at tempt to make a diagnosis of lead poi soning by any one laboratory finding.
I have seen workmen who have be come ill with relatively low urine leads. The man that I mentioned this morn ing, for instance, I believe had about --0.25 mg. of lead with no symptoms, and the day he got in the hospital, he had 0.14 mg. of lead per litre of urine. I do not believe that that was the result of any magical treatment that he re ceived in that interval. I think that is simply the variation in urine findings that one must expect in these cases.
On the other hand, I have seen men working for thirty years in the storage battery industry with urine values as high as 0.5, 0.6 and 1.0 mg. of lead per litre of urine, who have never been disabled, ill, lost any time and have shown no anemia, who have had no wristdrop, no lead encephalopathy. They have normal blood pressure and a nor
mal routine urine. One such man is still turning out a good day's work at the age of sixty-five, and he dales back to the time when conditions were not as we would desire them, when 25 years ago, 75 percent of the men had evidence of heavy lead absorption.
We know also that our lead in the air at times is much more than it should be, 3, 10, 12, 15, 18 mg. per 10 cu. feet. Of course, we have corrected that now with air line respirators using as much suction at the source of the dust as possible. In modern production meth ods, even when you are improving a situation, often the worker has to use the respirator.
Of course, no one can deny if the respirator is used continuously and no effort is made to correct conditions of lead exposure, it is a confession of en gineering weakness. If you wish, how ever, to keep men from being sick, I am afraid you are going to use respirators occasionally in the storage battery in dustry while protective suction equip ment is being fitted into production.
In fact, if that man I was talking about this morning, could have a job found for hijn, and I think it can be found, where he is using not an ordi nary respirator which he is likely to discard, perhaps, because he does not get enough air through it, and is given an air-line respirator, that would be just the same to me as if he were moved out from the lead exposure. I have done that again and again, and the man is still making good money and he is satis fied; the company is satisfied, because he goes on and continues his convales cence even while working.
We covered this morning, I think, what constitutes lead poisoning or true lead intoxication. Lead absorption is one thing; disabling lead intoxication is another. We are not using those terms to escape any responsibility. We are
DUP050314401
48 DISCUSSION
simply wanting to be precise, as we like to be in any field of medicine.
A sign of lead absorption, certainly, is lead line, a finding which can be easily determined by spot illumination, even a flashlight, or better still, a head mirror and a small hand lens which costs about ninety-five cents, inciden tally. One can then definitely say there is or there is not a deposit of linear or round row of dots in the gum tissue next to the teeth.
Of course, one should know that the individual has not been taking bismuth for the treatment of syphilis. Otherwise, the physician cannot rule out the fact that the apparent lead line may be a bismuth line. I have seen some per fectly marvelous lead lines that excited me and then I found out when the Wasserman report came back, and after a little private conference with the indi vidual, that he was getting bismuth as treatment for syphilis. In fact, some of the men doing syphilology insist that a patient is not receiving sufficient bis muth unless he shows a bismuth line.
One does not always see a lead line if a man has good teeth. A case that I had had perfect teeth and showed no lead line until after he was disabled. The pyorrhea, decay and detritus around teeth seem to be a precipitate of what is apparently lead sulfide in the gum. However, that is merely an evidence of lead absorption.
Certainly, if there is no bismuth to be confused with, and if one sees a lead line, one knows that the worker has had too much lead absorption and the phy sician should be on his guard regarding a possible disabling lead intoxication.
That is fully as important to me as the determination of the lead value in the urine. It is certainly a good deal less expensive.
In doing medical work in industry, one has to learn to fit in with produc
tion schedules. The men are not always anxious to come in for periodic re examinations even though it may be on company time, and the company is not too anxious to have them. However, I want to see the men as often as nec essary. That may be every day in some cases, though usually every two weeks and in some cases every month or three months, depending on the concentration of exposure. But to make an examina tion of the man for a lead line, to talk to him, really to get that patient-doctor relationship that Dr. Johns spoke about this morning, to take his blood pressure and to make a note and record the facts is usually a matter of only a very few minutes.
Then, if one's technician is working at the same time on another group of men and gets the hemoglobin and the stippled cells, one can fit, as you see, right into production. Nobody warms the chair very long. But we have our information, and we see the man as often as we need to in our best judgment.
We have men who have been having their cars stuck for blood every two weeks, for twenty years, and, if we miss them, we hear,from them. If we forget to call them in, they come in complain ing, "Why don't you call me in?"
That is something you would not ex pect, but those old-timers know the con ditions that were there before we started this system, and they know that it pays to have this medical observation. So much for lead line, which is a simple procedure and which I should like to illustrate presently.
Like a lead line, a few stippled cells, say, 5 to 10 per 50 fields, are also an indication of lead absorption but are not likely to mean lead intoxication. They are much simpler to study than lead in the urine. Lead in the urine is
extremely valuable in mass group stu dies. It is valuable for research pur-
1I
DUPO50314402
ii
-ii'riv; r"' -r- . . . . . . . -
PREVENTIVE MEDICAL ARMOR
47
poses and, certainly for medico-legal cases for doubtful cases.
I hope I have intimated that I have nD quarrel with people who are inter ested in doing lead in the urine. I think that it is a valuable and helpful adjunct, but as Dr. Fairhall has said, urinary lead excretion is orje of six cardinal factors in the diagnosis of lead poison ing and, standing by itself, a urinary lead indicates nothing but lead absorp tion.
I should like to emphasize the symp toms of lead intoxication. As I said this morning, if a man is sick, if he is really ill, if he is weak, if he is nauseated and vomiting, and if he has a real constipa tion or occasionally if he has diarrhea, and even more rarely, if he has a fleet ing arthralgia, or joint pains, with all the other factors, if we know that he has been exposed to lead, if he shows evi dence of lead absorption in some one of those ways, with those symptoms, plus a rising stippled cell curve, then we know that he probably has true lead poisoning. Then it is just and wise to admit it to the patient promptly and tell him what he has and see that he gets immediate relief. Fortunately, relief can be given to the most severe type of violent lead colic in 20 to 30 minutes after the injection of calcium gluconate.
I am especially interested in trying to make this clear to you today because this i3 what I try to make clear to . my medical students and what we also try to make clear to the doctors in . our county and state medical societies. The doctors are the harder problem, ' inci dentally. We make the distinction be tween lead absorption and lead intoxi cation, because, in a perfectly sincere manner, the average doctor who, per haps, has seen one or two cases of lead absorption and intoxication in his life, if any, even in medical school, often relies primarily on the statement of his
patient, "Yes, I work with lead." "What do you mean you work with
lead?"
"I work with paint." "What kind of paint?" "I don't know. All paint has lead, hasn't it?" Unfortunately, the doctor does not always pursue that type of questioning until he is forced to on the witness stand, and then it is somewhat embar rassing to him as a physician to admit his error in being led astray by his patient. In our State, our Industrial Commis sion examiners are often called on to act as attorney for an applicant, and I have heard them go through that questioning before a hearing comes to pass. If the applicant cannot answer intelligently, they say, "You have no case. Go find out what kind of paint you are working with." If the doctor has the facts he should speak with authority but the average doctor does not realize that he is re garded by a layman as an authority. One of our problems is to make the average physician realize the weight that is put upon his words. A patient often comes to him and says, "Doctor, I have been working .with lead, and I have a bellyache. Don't you think I have lead poisoning?" The physician often replies, "Well, I don't know; perhaps you have," and then passes it off. He does not even think of the possibility of this going to court. He finds a little anemia, with or without stippled cells; he may not even look for lead line and probably forgets to have a urine lead. Then suddenly he finds himself called up to a court hear ing and he has to make good the mis taken idea the patient had, that his physician thought he had lead poison ing. Such a physician is in for a bad half-hour on the stand, with a competent
! DUP050314403
48 DISCUSSION
cross-examination by an experienced at- exposure. By and large, by his own ad-
torney.
mission, the average doctor knows very
The physician, if he wishes to speak little about it except what he reads in
with authority, must make his diagnosis the textbooks. These, in many cases, are
one that will stand up not only in court perhaps twenty years behind the times,
but that he could get up and argue for The problem, then is one of educa-
before his county medical society. There tion of our young physicians as well as
is the jury of his true peers, and every education of the laymen, of management
word he says to them has to stand the and of the worker to distinguish the
severest kind of scrutiny. Even though points I have been making,
he knows that he cannot make a diagno- In regard to residuals, in my expe-
sis on one laboratory finding alone, he rience, the 90 percent of the cases which
must depend on exposure, plus the fol- go to make up lead colic come through
lowing facts:
without any permanent residual. True,
There must be evidence of lead ab- they may have temporary anemia. The ( sorption shown in the urine and gums lead palsy cases may have a residual,
or a few stippled ceils. There must be but not always, if treated properly,
actual signs of intoxication, usually a Lead encephalopathies, the third and
disabling colic and usually terrific con- rarest of the three types of lead intoxi-
stipation, obstipation, we call it, which cation, may have a serious residual, if
does not respond to any cathartic.
they recover at all, such as mental in-
That makes up the ordinary kind of volvement, but, again, they may come
lead intoxication. Ninety per cent of through, as did some of the ethyl-fluid
the cases are lead colic. Hunter, of cases, without any residuals at all.
England, has said that there are ten I would not like to leave anybody
times as many lead colic cases as lead with the impression that we do not meet
palsy cases. Most of us see very few lead poisoning anymore in modem in
lead palsy cases, fortunately. I have dustry. 1 agree with Dr. Johnstone, that
seen, perhaps, half a dozen in twenty- in the small industry we are likely to
five years.
have it all the time. It frequently ap-
When we have looked at this thing pears in unusual places in many small
from the point of view of industrial plants.
exposure, then we have to go at it from The accompanying photographs show
the standpoint of differential diagnosis, how we go in what we think is a 1, 2, 3
Does this man have a gallbladder colic? manner.
Does he even have a coronary occlusion Fig. 1 -- I show this photograph of
referred pain to the abdomen? Does inserting separators between storage
he have a pancreatitis? Does he have battery plates because I think any lay-
kidney colic? And, in the case of a man who has never done anything with
palsy case, are we dealing with, perhaps, lead -- and the average doctor has to be
an alcoholic, or infectious neuritis? It regarded as a layman in this area -- can
is a helpful sign that with most cases tell, by looking at the left-hand picture,
of lead palsy, there is no pain, and the that conditions in that picture are not
palsy is primarily extensor rather than nearly as good as they are in the right-
flexor.
hand picture.
I have gone into some detail on this You can see in the picture on the left-
because the usual physician has not had hand side that a plank has been thrown
experience with this type of industrial on the floor; lead dust can fall on the
DUP050314404
C/' ' PREVENTIVE MEDICAL ARMOR
49
Fig. 1--The old and new method of inserting separators between storage battery plates.
plank and be kicked up and inhaled. In the right-hand picture there is a slotted rack so the dust falls through to the floor where it will not be kicked up as dust and then can be washed down at the end of the working day.
In the right-hand picture again we have slotted down-draft suction tables. I think you can see for yourself that that man on the right has a much safer job. In spite of that, we insist that they wear respirators, whenever possible, though, practically, the engineering pre cautions there have cut the lead ex posure remarkably.
Fig. 2 -- Often we have the problem as to diagnosis of a lead line. "Doctor, have you ever seen one?" Some doctors admit that they have not, but I think
this picture proves that there is such a thing.
You see here the definite, punctate deposit of lead sulphide in the mucous membrane next to the teeth. The dirt and detritus on the tooth is not the lead line. That is what we see under a lens, a ninety-five-cent lens, plus a flash light. Thus, one can make the diagnosis in the home. If there is no bismuth treat ment here, the case is one of heavy lead absorption.
Fig. 3 -- We heard a good deal about this mythical character called "Mr. Stippled Cell" this morning. There is one. This is a white cell; these are red cells. There is another stippled cell. There are two stippled cells in one field, so that 50 fields would have about 100
DUP050314405
50 DISCUSSION
1
Fig. 2--The definite, punc tate deposit of lead sulphide, appearing as small black dots, in the mucous mem
brane next to the teeth.
stippled cells which is quite enough number of teeth opposite which there
often to be associated with disabling is a gum lead line, and the strength of
lead colic.
the wrist extension. We observe the
Figs. 4 and 5 -- This periodic re blood pressure finding also because we
t examination chart gives you an idea of are interested in finding whether these
1 the value of recheck studies. These ex cases are going to go on and develop
t aminations are made about every two an increased amount of hypertension
weeks with the date at the top; then at and arteriosclerosis as some have al
the side the particular symptoms that we leged in the older literature. To date
are looking for, either weakness, head we have not seen that in our experience.
ache, drowsiness, if there was a brain At the bottom of the chart we have
involvement and the usual gastro-intes- a place to record stippled cell count
tinal symptoms, such as constipation or
colic. We do watch the weight though the
weight does not give any specific in
formation, only to indicate something
as to the general physical condition of
the man. Then we test each man for extensor
weakness of the wrist at the same time
we are taking his blood pressure and
looking at his teeth. Teleky, I think,
was the one who brought out most
clearly the importance of testing the
extensors prophylactically.
We make a note as to the pallor, the
Fig. 3--Photomicrograph showing stippled blood cells.
! i
DUP050314406
PREVENTIVE MEDICAL ARMOR
51
HISTORY
1. NAME
. 2. STUDY NO.
BIRTHPLACE
3. ADDRESS
4. M. F.
W. B,
S. M.
W. D.
5. FAMILY DR.
6. WHAT TYPE.WORK APPLIED FOR:
7. HISTORY OF PREVIOUS EMPLOYMENT IN THIS PLANT:
CLOCK NO. DESCENT PHONE
L.R. AVER. WT. WT. 1 YR. AGO
8. HISTORY OF PREVIOUS EMPLOYMENT IN OTHER PLANTS;
DATE AGE
GREATEST WT.
9. FAMILY HISTORY
GOITER -- HEART
BRIGHTS
TBC.
_________ DIABETES______________________________
10. PAST HISTORY:
ILLNESS {SCARLET - RHEUMATIC FEVER)
_________ OPERATIONS__________________________
_________ ACCIDENTS _________________ _________
VENEREAL TREATMENT
_________
REMARKS: ..... ..
11. PHYSICAL EXAMINATION:
DATE
WEIGHT
HEIGHT
EST. WT.
PULSE
TEMPERATURE
PALLOR
LEAD LINE OF TEETH
R. WRIST EXTENSION
L. WRIST EXTENSION
LUNGS
GLANDS
ARTERIES
B. P.
HEART
ABDOMEN
REFLEXES
HERNIA
SPINE
EXTREMITIES
VISION-R.
L
VACCINATION
12. LABORATORY EXAMINATION:
STIPPLING 4f IN 50 FIELDS
HGB. <SAHU)
R. B.C.
W. B. C.
URINE
WASSERMAN
13. DIAGNOSIS:
PRE-EMPLOYMENT
B. H.
EXP.
UPON DISCHARGE
14. RECOMMENDATION:
Fig. 4--Periodic re-examination chart (front).
DUP050314407
52 DISCUSSION
Form 804
PERIODIC RE-EXAMINATION
NAME
Number
DATE
OCCUPATION
DURATION
PREV. PO. EXPOS. HISTORY
WEAKNESS
--
.
DROWSINESS
INSOMNIA HEADACHE VERTIGO
!
1
BOWELS # TIMES WITHOUT CATH. CONSTIPATION DIARRHEA METALLIC TASTE
1
1
i---------- 1
;
ANOREXIA NAUSEA
l1 I
VOMITING
1
ABDOMINAL OR CHEST PAIN
1
WHERE
-
1
WHEN
~1
WT. AVERAGE
[!
RESP.
| 1!
---------- !---------J 1
MUSCLE WEAKNESS
|
MUSCLE TREMOR
.I
ii i
!
MUSCLE TINGLING
| i: !
MUSCLE CRAMPS
! I: '1
j, JOINT PAINS ACUTE ILLNESS
1 j :1
i!! 1: , ; ;---------- J
;
PHYSICAL EXAMINATION PULSE - TEMPERATURE
i:
1i ;
^r
PAtLOR LEAD UNE # OF TEETH
......--
R. WRIST EXTENSION
i
L. WRIST EXTENSION
LUNGS
GLANDS
B.P.
HEART
ABDOMEN
REFLEXES
HERNIA
SPINE EXTREMITIES
--
LABORATORY EXAMINATION STIPPLING # IN 50 FIELDS HGB. (SAHLI) R. B. C. W. B. C. URINE WAS5ERMAN
i
t
RECOMMENDATION OR RX`
Fig. 5--Periodic re-examination chart (back).
!
j
I
DUP050314408
PREVENTIVE MEDICAL ARMOR
53
and the hemoglobin. In one particular statement that there is no short cut to
b,: case, early in the game, when we did clinical medicine. As Dr. Mayers has
not take warning quick enough, he said, every single case has to be viewed
was running 10, 21, 30, 110, 217 stip as a whole, from the viewpoint of gen
pled cells and we still let him stay on eral differential diagnosis, and one must
the same job. He began with diarrhea, study the whole picture, not any one
which was an intestinal influenza, and at laboratory finding, not even stippled
first he had no lead line. Then he sud cells alone.
denly blew up with constipation and Knowing these things to be facts, we
afterwards he had his lead line.
can, with good conscience, go about our
The anemia was a late development job of keeping the worker healthy and
here. That is the most important thing, I at work.
think, in the blood picture regarding
Ch a ir ma n Bo w d it c h : We are so be
lead. We all agree that lead stippling, or hind schedule that I think we had better
stippling of red cells is not a specific in confine any further discussion to a brief
dicator for lead absorption or intoxica reply by Dr. Lanahan, if he so wishes.
tion. You may find it with Hodgkin's Anything more cam be at the end of the
disease. Benzol poisoning, tumor, malig afternoon, if we have time.
nancy, any type of severe anemia, will Dr . La n a h a n : Dr. Belknap posed sev
eventually show nucleated red and stip eral questions in relation to my presen
pled cells, but with the lead intoxication, tation. The one that strikes me as most
you get your stippled cell rise early, long important is whether or not we plan to
before the hemoglobin drops.
use urine lead determinations to make
In this case he did not have his drop our diagnoses of intoxication, or resort
to 65 and 60 hemoglobin until after he to other measures.
was disabled. If we had been relying on He has touched on the heart of what
the hemoglobin, we would have allowed I feel is our presentation. The problem
him to go a lot further than we did, ab of which we are intolerant in our present
sorbing even greater amounts of lead. program is that it is a diagnostic pro
Following calcium gluconate intra gram. When we apply our proposed
venously, the patient went back to work analytical studies as we are determined
and worked for two or three years. He to apply them and are faced with a
was in excellent physical condition be diagnostic problem, we will admit to
fore he left our employ. He went back ourselves that we have failed somewhere
to the same type of work, incidentally, along the line, foiled in prevention.
but with a respirator. This particular Our persuasion to head in this direc
man had been working at a job where tion is based on the studies that have
nobody thought he had a lead exposure. been made by Dr. Kehoe and others who
He was working in the forming room, have established the ranges of blood and
normally a wet room, but he was the one urine lead levels that are compatible
man in the department who was drop with health, that are seen in people with
ping dry plates into a battery ease. He known occupational exposure, accepting
did not show up for examination until these ranges as our starting point. We
he got sick. We did not like that; we like hope to keep our people within a range
to be able to put our finger on these of lead excretion compatible with such
cases of impending intoxication three or standards. As we see them working their
four months ahead of time.
way above such standards, we hope to
I think I should like to close with the make more extensive studies to catch the
DUP050314409
54 DISCUSSION
bugs in our rapid method. At this stage we feel that we will be ahead of clinical symptoms and stipple cell changes. We will be before the stage of diagnostic procedures, using preventive methods.
Dr. Belknap has asked, if urine deter minations will replace physical examina tions. As I mentioned in the preface to my presentation, in spite of, let's say, the abundance of our medical personnel, we feel that we are not able to watch our people as intimately as necessary to pre vent diagnostic problems.
We are looking for something which will give us a signpost by which we can have our fingers on everyone before they become diagnostic problems, and we hope that onr proposed method is the measure by which we may accomplish this. When we find groups, and the indi viduals within the groups, having excre tory ranges above those which have been declared as compatible with health, we will resort to our present program of physical examinations and complete blood studies, repeating them as fre quently as we wish.
Again, let me say, when we have a diagnostic problem, we will admit that our preventive medical program has a hole in it.
Dr. Belknap asked how soon we can plan to review these people, if it re quires one technician for 30 or 40 deter minations daily? Our present program, which I have described as involving study of stippled cells, hemoglobin deter minations and personal communications with these people, entails the entire acti vity of two laboratory technicians.
We estimate that it takes them 20 minutes for each technician to do each laboratory study, which results in the determination of the hemoglobin and the stippled cell count. We believe urine studies will involve no greater time and will require no additional technical per
sonnel.
Our chemist, who at present does our lead in air determinations, can oversee the precision of our laboratory analyti cal studies, for I do not presume to be so qualified.
I might add this. In Fig. I, Dr. Belknap presented to you the picture of an assembly line, with grating in the floor and the down-draft in the table. Men were wearing respirators.
It is my routine to accompany the gen eral safety committee which, inciden tally, is a management-labor coordinated committee, in visiting every procedure throughout both plants once a month. I would love to find that each time we passed the -assembly line and any other process we bad, we would see our men actually wearing respirators, where they have been issued.
The respirator is either, obviously, down on his chest or it is in a position where he can quickly duck his nose under it as we are going by.
We have down-draft; we have water under the grates, and we have respira tors. Our air levels worry us. We have people getting sick. We are doing what all of you are doing, and we are not satisfied with it.
Ch a ir ma n Bo w d it c h : This seems an appropriate moment to repeat Mr. H. J. Weber's very excellent definition of the industrial respirator. He has aptly de scribed this device as "A muzzle type ornament worn loosely pendant from the neck, used in dirty industries to dis tinguish the laborers from the office employees."
I am sorry that we cannot continue this discussion further at this time, for I know that there are one or two others who could contribute valuably to it, but we must get on with the program and hope to be able to continue at the end of the afternoon or, if not, then to morrow.
Our next speaker was the physician
DUP050314410
CO-ORDINATION OF MEDICAL SERVICES
55
of the Massachusetts Division of Occu pational Hygiene from 1940 to 1942 and then became director of the Louisi ana Division of Industrial Hygiene. He went from that position into the Army as a battalion surgeon in the infantry. Then, in 1946, he became physician of
the American Smelting & Refining Com pany at Tacoma, Washington, and in 1947 was appointed medical director of that company, with headquarters in Denver, Colorado.
Dr. Sherman S. Pinto will discuss The Co-ordination of Industrial Medical Services.
THE CO-ORDINATION OF INDUSTRIAL MEDICAL SERVICES
By SHERMAN S. PINTO, M.D. Medical Director, American Smelting & Refining Co., Denver, Colo.
In a medical program embracing many widely scattered plants it is es sential that careful consideration be given to centralization of some and de centralization of other procedures. In this talk I wish to point out where centralization is advantageous and also where decentralization is preferable.
Medical care in industry is more than bandaging cuts, setting fractures and passing out aspirin for headaches. An industrial medical program should be designed to prevent disease, recognize sickness early so that treatment can be started before serious consequences have developed, and help employees secure the best medical care when sickness does occur.
Now let us examine the various parts of a medical program to see how they fit into the general picture.
The medical examination form is one of the basic tools of industrial medicine and great care should be exercised in its adoption.
It is preferable to use the same medi cal examination form throughout one company. This establishes uniformity -of procedure and allows certain aspects of the examination to be stressed.
Medical examination forms are ex tremely varied and there is no universal
form applicable to all industries. We considered numerous forms used in in dustry, insurance forms. Army forms and hospital forms before we drafted a form for our own use. The form we now use is as simple as we could make it, yet all the essential and important in formation desired can be recorded.
It was also designed to allow the doctor to make the examination with a minimum of writing. Most of us dislike to write extensive records and will make better reports if they can be written briefly.
At the top of the accompanying form is the usual identifying data, name, ad dress, etc. Immediately below that is a section for recording past occupational history. Most medical schools sadly neg lect the occupational history but we feel it is especially important in the lead industry. We have found a number of men applying for work in lead plants who will state in their occupational his tory that they recently quit work in another lead plant. Obviously such men should be studied very carefully for evi dence of abnormal lead absorption be fore they are put to work and exposed to more lead fumes and dust.
In the occupational history we also stress exposure to dust in former jobs.
DUP050314411
56 PINTO
Many of our plants have ore crushing operations and we have found it im portant to know whether or not a man has been exposed to silica dust on other jobs. We hire men with early silicosis.
for instance, but we put them on nondusty work.
The usual medical history is recorded in the next space. As you can see, a number of diseases have been- mentioned
AMERICAN SMELTING AND REFINING CO.
PLANT Fill out this blank IN DUPLICATE and sond carbon copy to office of Medical Director, Shaman S. Pinto, IS. D., BO? First National Bank Building, Denver 2, Colorado. Original to remain in doctor's or narea's die in plant dispensary as b confidential record, available only to plant doctor or none.
{Trial ar l>pa SpalliBC at aa Hoc!*) Samritr cart)
JI8WD M. F.
OCCCPATIOHAIi HISTORY (Oar nit asnnri t Cut or fomul _ If aa. pn drcosataaua, fnalbB and da
MEDICAL HISTORY, (Any o! loUowtftgr in poll? TOUEFCOZOSIS. ASTHMA. BEAST DISEASE. EKEUMAHSM. DIABETES. EPILEPSY, VENEREAL DISEASES.
DISEASES DUE TO OCCUPATION. DERMATITIS. AUENGIES. w|nun`tt OFQtATIONS. U to, piv# drcwaatencet. duration and dalaa.)
'
fSa* BuUatia ol Inalruetiooi lot aalaSa all 1total fctlote). FtSAtOatSaFEtuCTntVSfrccEnMpaPULaOaylUir OLD EMPLOYEE? {Total yaaob SUla oeoopatUa)
msorr c o mp l a in t s ?
DATS Or EXAMINATION
DATE OF SUMMATION
DATE OF EXAMINATION
WEIGHT-HEIGHT
TEMPS2AS0BE
GENERAL APPEARANCE EVES
VISION--Sight T 1 OtfldilAMA
VISION--Loll f St*CS,>rt*
1 J0~ U Car- 20 ii -- -- IlCtld -- --
to20 H Cr> 23 44
-- -- itdad -- --
20 H ---- 20 U ----
Cor* a ii
ractad -- --
to .Car- 20- II
(acted -- --
20 l Cm- 20 li -- -- nctad -- --
to 20 U Car- 20 U -- -- ractad -- --
NOSE AND EARS MOUTH
THROAT AND NECX
HEART
BLOOD PSESSUBE
CHEST AND SUNOS
ABDOMEN
BACK
HERNIAS AND UKOS
EdlDOTIEI
VAgCOSE YENS AND
I, sxnr
ii EMOTIONAL STA9IUTT
OTHER nNSSIOS
KD-S--10-49
Fig* 1---Medical examination chart (front).
DUP050314412
CO-ORDINATION OF MEDICAL SERVICES
57
by name. This was done to remind the doctor not to overlook those diseases which might have sequelae of import ance for work in industry.
On the lower part of the sheet are
three columns for recording physical findings. The first column is used for the initial examination, the other two for subsequent examinations. As you can see, all the findings which the doctor
(Sm Euliatm o! toctnetioM ta details on all Itatet feakiw) _
P URINALYSIS
g BLOOD SESOLOBT
^ COMPLETE BLOOD COUNT
^ O STIPPLED
COUNT
2 3 l ead in treats
" S LEAD IN BLOOD
" DA7E 07 BUSONATION
DATE OF EXAMINATION
DATE OF EXAMINATION
OTHER LABORATORY
CHEST X-RAY FINDDICS
SUMMARY OP ALL SiatJtnCAKT FStDOtOS
RECOMMENDATIONS
WAS PROSPECT HIRED?
IP HOT HOED. STATS WKT
i|
MAY REGULAR EMPLOYEE CONTINUE PRESENT DUTIES
17 NOT, STATS WHY
FAMILY PHYSICIAN AND ADDRESS EXAMntSta DOCTOR IPItu* Sign)
DISPENSARY RECORD OB C THER MOTES
Fig. 2--Medical examination chart (back).
DUP050314413
58 PINTO
makes are recorded on one side of the letin explaining every item on each line
form. There is no necessity to turn the of the examination form. This bulletin
form over, and a carbon copy can be is given to all plant physicians so they
easily. made.
may understand just what is included
The reverse side of the form (Fig. 2) in each item.
is used for recording all types of ex
Before a man is hired he is given a
aminations which might be made in a thorough physical examination. This is
laboratory. Only those spaces are used done for the purpose of determining the
which are required, and not all that type of work he is best suited for
laboratory work is done on each man. physically as well as to see that the
Near the bottom of the form are sev work he is going to do will not be in
eral questions for the doctor to answer. jurious to him. Thus, a man with der
The first question is, "Was prospect matitis would not be hired for a job
hired?" The next question is, "May in which he might have excessive ex
regular employee continue present du posure to a skin irritant. In certain
ties?" In essence the answer to these plants all jobs go by strict seniority
questions represents the doctor's final while in others men can be hired for
medical opinion of the man and his rela specific jobs. For this reason the de
i tion to the job.
cision as to whether or not a man is
At the bottom of the form is a space qualified for a job must be made by
for clinical notes which are made when the local doctor. We do not attempt to
a man returns to the dispensary for any lay down hard and fast rules for pre
sort of treatment. Thus, on this one employment physical qualifications.
i
sheet we have a serial record of an em
Periodic examinations for hourly em
ployee showing his physical examination ployees are a form of preventive medi
at three different times and a brief cine. Most of our employees are examined
record of his treatments in the dispen every two years and all findings of sig
sary during that time. Sometimes more nificance are discussed with the patient
space for clinical notes is needed and The examination itself may include spe
a blank sheet can be attached to the cial laboratory work if such seems indi
original one for this purpose.
cated provided the cause of the disorder
Such a form as I have described is suit is the result of an industrial process. This
able for pre-employment and periodic ex includes such things as urinalyses for ar
aminations of workers in any type of a senic, selenium, etc. For special types of
smelting plant, and will also serve for examinations which seem necessary for
keeping clinical records. It is a multiple- further diagnosis as in cases of early
use form from which unnecessary exam cataract, suspected cancer of the gastro
inations and questions are eliminated. intestinal tract, etc., the patient is referred
The family history, for instance, has to his own physician. No man is fired
been eliminated since we found such because of a disability but on the phy
little information of practical value. sician's recommendation he may be al
Similarly, you can see that routine lowed a year's sick leave with retention
measurement of the size of chest and of seniority rights.
-,
abdomen have been discarded. These Men quickly realize when periodic ex
are time consuming procedures which aminations are for their benefit and we
have no particular significance in an have had the experience of men ori a
industrial medical examination.
picket line come to the dispensary dur
We also wrote a comprehensive bul ing a strike and ask for their periodic
DUP050314414
CO-ORDINATION OF MEDICAL SERVICES
59
examinations. They knew the examina munity. Later a type of influenza ap
tion was for their benefit and any dis peared protection against which was not
ability which might be found would not provided by the vaccine. As a result
be used as an excuse for discharge. many employees became sick and were
Similarly, we have had a union official antagonistic to the further use of pro
with heart trouble ask us if it would be tective vaccines. Preventive medical
safe for him to make an extensive air measures must have a reasonable chance
plane trip at a time he was engaged in to succeed or the whole idea of preven
contract negotiations. Such a question tion will be discredited.
puts the doctor very much on the spot The chest X-ray has become an im
because if he says the trip should not portant part of the examination pro
be made the doctor might be suspected cedure. For plants with 1,000 or more
of trying to sabotage the union's part in employees the purchase of an X-ray
the negotiations. However, the important machine by the plant is justified. For point is that a medical department can smaller plants, arrangements are made
have the respect and confidence of both to have chest plates taken by a local
union and management if it is scrupu doctor. Labor turn-over is still high in
lously fair and honest in its work.
many parts of the country so we often
The question is often raised whether do not take a routine chest X-ray until
industry should engage in preventive a man has been on the job 30 days.
public health medicine. We feel that However, if the man gives a history of
when local conditions call for preventive arrested tuberculosis or exposure to sil
medical practices, industry should parti ica dust, an X-ray is taken immediately
cipate. Plant-sponsored smallpox vacci as part of the pre-employment examina
nations at a time when there is a local tion. Abnormal chest films are sent to a
smallpox outbreak is an example of the central office for consultation. We feel
type of preventive measure I have in only a recognized expert can be ex
mind.
pected correctly to interpret the evidence
The administration of influenza vac of early tuberculosis or pneumoconiosis.
cine is another measure about which By the same token many men are ap
there is controversy at present. During proved for employment who have healed
the last two years influenza outbreaks chest lesions of what was probably a
have been local in nature and the type fungus infection of the lungs. We are
of infecting organism has varied in dif interested in trying to put a man to
ferent communities. Such outbreaks have work. That should be the aim of a
also varied as to time of appearance in medical examination, not to try and
various parts of the country. We have keep men from working.
asked our individual plants to watch In a company-wide medical program
'I closely for the appearance of influenza practices which are found beneficial in in the community. If a type of influenza one plant can be extended to all plants.
appears for which a suitable vaccine is When doctors know they are part of a
available we recommend that the local company-wide plan, they become more
plant make an effort to vaccinate as interested in the workings of the plant.
many of its employees as possible. This We encourage all our doctors to visit the
is done at Company expense. Two years various departments of their plant fre
ago some of our plants pushed the ad quently and become familiar with all
ministration of influenza vaccine before operating procedures. Only when a doc
any influenza had appeared in the com tor understands a man's job can he cor-
I DUP050314415
60 PINTO
rectly evaluate the presence or absence of the health hazards connected with that job. In the central office, we keep in close touch with company management and are acquainted with new developments and processes which are to be installed in plants. Having in mind the potential hazards of a new process we are able to visit the doctor at the plant concerned and acquaint him with the new process at the time it is started, Many times this has proven the truth of the old axiom that "an ounce of prevention is worth a pound of cure."
Medicine in general and industrial medicine in particular is entering a new era. Whereas the disease process of the individual patient has been of primary concern in the past, we are now intensely interested in the environment and its possible effect on the patient. The atom bomb has made us all acutely aware that the environment can suddenly and violently affect the health of an individual. Modern industry has changed remarkably in the last 15 years and almost all industries use many more toxic chemicals now than were employed formerly. Thus in a more widespread but less dramatic fashion the modern industrial physician is as concerned with the environment as is the doctor surveying the effects of an atomic explosion on the general population.
Our studies of the plant environment are centralized rather than left to the individual endeavors of each separate plant. At a central laboratory are men trained in industrial hygiene -- trained te make all the necessary air studies for fume and dust control. They are equipped with all the necessary instruments, and this expense is justified since they use these instruments the year around. Check surveys are made in each plant at least once a year, and all operations producing questionable amounts of fume or dust are studied. An im-
portant part of such studies is to differentiate between conditions which are a nuisance and those which are a definite health hazard. In the control of poor conditions a higher priority is naturally given to the control of definite health hazards than to the nuisance conditions,
A program of periodic urinalyses has been adopted as another measure of the effectiveness of engineering control in the manufacturing process. With regard to lead, all men potentially exposed to lead dust or fumes have a routine urinalysis for lead at periodic intervals. Urine samples are collected at the indi vidual plants and sent to the central laboratory for analysis. The samples are collected in glass bottles which have paraffin-lined caps and are shipped in wooden containers. This has proven very satisfactory and we have much confidence in the urinary lead determination which is done routinely by a skilled chemist. Urinary lead analyses done infrequently by a chemist are often subject to error, and we feel that centralizing the urinary lead determinations results in much greater accuracy, For emergency determinations a sample can be airmailed from any part of the United States on one day and the result telegraphed to the sender within 24 hours. Ordinarily, routine samples are sent by train.
The centralization of the industrial hygiene laboratory also allows the chemists there to become proficient in anaIyzing urine for the rarer non-ferrous metals. The need for such determina tions in any one plant is infrequent but the aggregate from a number of plants provides a sufficient number of samples to assure a chemist maintaining his skill in running that determination,
All individual urinary lead determinations are recorded in the central medical office on graphic record cards as shown in Fig. 3. By this means, a continuous
u
DUP050314416
f
AMERICAN SMELTING AND REFINING COMPANY URINARY LEAD CONCENTRATION
CO-ORDINATION OF M EDICAL SERVICES
wpssss
62 PINTO
visual record is easily kept. If a man's brains of the executive group is a com
urinary lead level reaches an unfavorable pany's greatest single asset, and it is
height or starts to show an unfavorable important that the health of these men
upward trend, the plant manager's atten. be properly protected. We have a sys
tion is called to the case and steps are tem of annual examinations for the ex
taken to reduce the man's lead exposure. ecutive group which includes a chest
As a point of interest, I should like to X-ray and an electrocardiogram. The
point out that urinary lead analyses occa examinations are made by a doctor of
sionally bring to light unexpected lead the man's own choosing, and copies of
exposures. One such case that we saw the examination are sent to the central
I
recently was in the operator of a plant medical office. These records are strictly vacuum cleaner. Apparently the cleaner confidential at all times. Since execu
bag leaked slightly and the operator tives are sometimes moved from one
absorbed enough lead dust from this plant to another, it was found ad
leak to show an excessive exposure.
vantageous to file their records in a
The graphic record cards are useful central office. Thus, these records are
| in following the individual employee easily available if a man wishes to have and may also furnish other information. his old records compared with more re
The records of the same department in cent ones. If the examination discloses
several plants can be easily compared a physical condition which should be
and the effectiveness of control measures corrected, the executive is contacted and
in different plants brought out. Similar urged to get the necessary treatment.
ly, different departments in the same The cooperation of the executive group
plant can quickly be compared and the has been splendid and the vast majority
place where further engineering control have expressed their appreciation of
is necessary becomes quite evident.
such examinations.
New construction and new processes The last point I would like to men
are of interest to the medical department tion is the medical care of non-industrial
because we feel it is much simpler and illnesses. This is a subject about which
less expensive to build proper controls there is much discussion at present, and
into new construction than it is to add I anticipate more in the future.
them later. This acquaintanceship with Prepaid medical care plans are nu
new construction is primarily a problem merous in type and complexity, and
for the medical director since he is in local workman's benefit associations,
closer touch with company operations. commercial insurance plans, and Blue
Several engineers specialize in ventila Cross are familiar to all of you I am
tion and wc work in close cooperation sure. These plans have been devised
with them. When a new installation is because there was a demand for them.
completed we make atmospheric tests In- addition, the idea of compensation
f!l
for fume and dust control. If a ventila for time-loss due to accidents is almost
tion job is effective and satisfactory, it universally accepted in American indus
will probably be used as an example in try. As a further extension and broaden
later installations so we work with the ing of these two ideas, sickness benefit
engineers to make each new type of unemployment insurance is being advo
equipment as satisfactory as possible. cated in many states. At present two
An important part of any medical states have such insurance in force and
program is the development of periodic in a third it was started in January,
examinations for top executives. The 1949.
1
DUP050314418
CO-ORDINATION OF MEDICAL SERVICES
63
This type of legislation affects indus trial medical practice particularly if there is a difference between the amount paid for accident benefits and sickness benefits. Thus an employee with a low back pain of rather vague origin will wish to have his disability classified under the fund which will pay him the greatest benefit. It is important, then, that such legislation be carefully studied when it is proposed and suggestions made to keep accident and sickness bene fits comparable. Furthermore, there should be no duplication of payments from both accident and sickness funds for the same disability. Such duplica
tion places a premium on accidents and
defeats the purpose of the legislation. Ch a ir ma n Bo w d it c h : I am afraid
that, for lack of time, we will have to
continue to the next subject without dis
cussion of this one.
Our next speaker is, again, one of the
younger group, a man whose principal
interest, until recently, has been in the
field of biochemical and physiological
research. For the last year and a half
he has been senior industrial hygiene
physician of the New York State Depart
ment of Labor.
Dr. John E. Silson will discuss Med
ical Control of Lead Workers -- A State
Viewpoint.
.
5 |
i
I
DUP050314419
MEDICAL CONTROL OF LEAD WORKERS -- A STATE VIEWPOINT
By JOHN E. SILSON, M.D. Senior Industrial Hygiene Physician, New York State Department of Labor, New York
Lead poisoning is one of the oldest workroom where lead is handled, and
and best known of the industrial dis requires the employer to provide a suit
eases, and for this reason was one of the able eating place; and another which
first problems to confront the various requires that the employer supply hot
governmental industrial hygiene agen water, soap and towels to all employees
cies. Today, after many years of experi exposed to lead. All cases of lead poison
ence, countless statistics and innumerable ing must be reported to the Labor De
studies, its control still remains one of partment.
the principal tasks of the industrial hy
To carry out these and other provi
gienist. The Division of Industrial Hy sions of the Labor Law, the Division of
giene and Safety Standards of the New Industrial Hygiene has been established
York State Department of Labor, like as a part of the Labor Department. In
its counterparts in other states, is con this respect it differs from most other
stantly made aware of instances of ex states, where industrial hygiene is a
posure of workers to excessive amounts function of the Health Department. This
of lead. Through the years, many prin enables the Division to integrate its
i ciples of control have been evolved work closely with the other units of the which are applicable to some of these Department responsible for protecting
cases; but others may present problems the workers. Codes for the safe opera
requiring a new approach and an indi tion of factories and other industries are
vidual solution. This paper will present drawn up by a special unit of this Divi
certain aspects of both the standardized sion. The enforcement of these Codes is
procedures which the Division has facilitated by cooperation between this
evolved and the special problems which Division and the Division of Industrial
it has met.
Safety Service. All equipment for the
New York State has always been in control of atmospheric contaminants
the forefront in the field of labor legis must be approved prior to installation
lation. Similarly, it has pioneered the by the Industrial Hygiene Engineering
entrance of the states into industrial hy Unit; and plans for all factory and mer
giene activities. The State Labor Law cantile buildings outside New York City
provides for protection of employees must have the approval of another En
i*i from "dust, gases, fumes, vapors, fibers gineering Unit. This results in informa
:!i
:i
or other impurities .... generated or tion as to hazardous operations coming
released in the course of business car to our attention at the onset and cur
ried on in any workroom or factory in rently from such sources as the factory
quantities tending to injure the health." inspectors and the Workmen's Compen
Under this provision, the control of lead sation Board.
fumes and dusts has been made the Tied into all these activities are the
responsibility of the Division of Indus functions of the Medical Unit. It inves
trial Hygiene and Safety Standards. tigates cases of industrial disease to
There are further provisions in the La advise on prevention and control, con
bor Law specifically applicable to lead; ducts field research in various poten
one which forbids taking food into any tially hazardous industries, organizes
64
DUP050314420
MEDICAL CONTROL
65
programs of medical control where work ers are exposed to toxic substances, and assists outside physicians in the dif ferential diagnosis of cases of doubtful industrial poisoning. It has also been of assistance in helping plants set up med ical offices, and in planning special hy giene facilities for factories with par ticularly hazardous exposures, it has on its staff an industrial nurse consultant conversant with the problems of running a plant medical office, and a nutritionist experienced in organizing and improving plant cafeterias, lunch rooms and other eating facilities.
In carrying out these activities in plants where an exposure to lead exists, we have observed a wide disparity in the nature and extent of medical supervision of the exposed workers. In some plants, almost complete reliance is placed upon stipple cell counts; in others, urine ex aminations for lead concentrations alone are employed. Still other plants are either unaware of their hazard, or do nothing about it for other reasons. Even where fairly complete examinations are made, considerable variation in the in terpretation of results has been found.
MEDICAL CONTROL PROGRAM
In the interest of promoting good in dustrial hygiene, and of spotting cases of lead absorption before poisoning oc curs, the Division has drawn up a pro gram for the systematized periodic survey of workers in plants handling lead in any of its forms. The recom mendations embodied in this program are the minimum controls which should be maintained in order to insure the health of the workers. They are predi cated on the realization that laboratory tests and mechanical analysis cannot supplant the intelligent observation and evaluation of the worker as an individual by a properly qualified physician. On the other hand, it is appreciated that the
average plant physician cannot do un limited numbers of complete physical examinations. This plan is designed, therefore, to assist the physician in de tecting early cases of increased lead ab sorption or intoxication by screening all the workers at frequent intervals.
In a plant with a limited number of lead workers, this screening could be easily handled by the plant physician himself. Where larger numbers of em ployees are involved, however, the fre quent screening examination might be done more conveniently by the plant nurse or medical technician, leaving the physician more time to evaluate the re sults and to call in those workers with abnormal findings for additional exam inations. This would require an indi vidual specially trained in hematological technique who would be given supple mentary instruction by the physician on what to observe in the screening exam ination and on the proper method of collecting urine samples to avoid con tamination. Such lay personnel, how ever, should be carefully supervised by the physician in charge.
CLASSIFICATION OF WORKERS
The program is designed to cover all workers handling lead in a plant or those performing special functions which bring them into contact with lead in any form, whether as fumes, dusts, mists or vapors. Variations will undoubtedly be necessary depending upon the number and percentage of workers in a plant who are exposed Lo lead, and the extent of their exposure. In general, particu larly in those plants where the majority of the workers are so exposed, it has been found advisable to divide the workers into two groups. Group A, the high exposure group, should consist of all workers directly exposed to large amounts of lead or lead compound dusts, fumes, and mists, such as burners.
DU PO50314421
68 SILSON
oxide makers, pasters and dry-plate Cholak of the Kettering Laboratories
handlers in battery plants; pigment published a greatly simplified test for
grinders, blenders and baggers; paint urinary lead. The method has certain de
mixers and sprayers; smelters and cast ficiencies in that it does not eliminate
ers in lead, brass and other alloy foun bismuth and certain other possible con
dries; and all other workers, including taminants, and is only applicable to
porters and maintenance men, whose freshly voided specimens. It is ideally
occupation involves exposure to high at suited to a rapid screening technique,
mospheric lead concentrations. Group though, since any false results obtained
B, the low exposure group, should in will be higher than normal. This en
clude the less exposed workers in plants ables one to eliminate from further con
handling lead or lead compounds, such sideration all those specimens which are
as shippers; wet-plate battery assem reported low, by a procedure which can
blers; all workers in typesetting and be rapidly performed on large numbers
casting rooms of printing plants; work of specimens.
ers engaged in wet processing of lead,
Utilizing this method, "spot samples"
and all other workers whose occupations of urine should be analyzed for lead
involve exposure to relatively lower at monthly on all workers in Group A, and
mospheric lead concentrations.
every two months on those in Group B.
"Spot samples" are advised, rather than
SCREENING EXAMINATION
24-hour or other large collections, both
The program is based on a periodic screening examination of all the employ ees. The physician, plant nurse or med ical technician should interview each worker in Group A monthly, and in Group B every two months. The worker should be observed for pallor, tremor and lead line, and questioned for the fol lowing symptoms: weakness, headache, vertigo, fatigue, insomnia, anorexia, nausea, vomiting, constipation, diarrhea, abdominal cramps, metallic taste in nouth, tremors, and joint and muscle pains. Ail workers having abnormal signs or symptoms should be referred immediately to the plant physician for a complete examination.
to meet the requirement for freshly voided urine, and to avoid the danger of contamination. The variations intro duced by this method of sampling are more than compensated for by the abil ity to make frequent checks, and can be further controlled by correction for spe cific gravity. Since it has been shown that the fluctuations in urinary lead bear a ratio to the solids excreted, and the latter in turn are roughly proportional to the specific gravity, it has been rec ommended that all lead determinations be corrected to an average specific grav ity of 1.024. In essence, this merely allows for any additional water excreted through diuresis, which appears to have little or no effect on the actual lead out
LEAD IN URINE
put. It is accomplished by determining tlie specific gravity on each specimen
Until quite recently, the techniques analyzed, and multiplying the lead value
for the determination of lead in urine obtained by the factor 24/G, where "G"
were so time-consuming and laborious represents the last two figures of the
that frequent examination of the urine specific gravity of the specimen.
of all exposed employees was economic
Where a corrected value of 0.1 mg.
ally unfeasible in many cases. In Janu per liter or greater is obtained by this
ary, 1948, however. Professor Jacob screening technique, the test should be
T
DU P050314422
MEDICAL CONTROL
67
|f repeated by one of the standard labora- ical control, a complete history and
I tory methods. This could be done on a physical examination should be given
ft, spot sample again, or on a larger sample each worker, and this should be done
I' collected oft the job. Twenty-four hour for each additional worker subsequently
I' specimens collected in part during work- hired, at the time of his employment.
l: ing hours are not advised, because of This examination should include, in ad
f the danger of contamination. When the dition to the usual pre-placement med
recheck examination confirms the find ical examination, a complete history of
! ing of 0.1 mg. or higher, the worker should be kept under observation, and examined again within two weeks.
previous employments, with special em phasis on exposure to lead and an inves tigation for neurological abnormalities,
blood dyscrasias, and cardiovascular
HEMATOLOGY
and kidney diseases. Workers in these
! Blood smears should be taken on all categories may be more readily injured
j workers and studied for abnormalities, by lead exposure.
such as stippling, polychromatophilia
A repetition of the complete physical
and changes in morphology. This pro examination, with an interval history,
cedure should be carried out monthly on should be given each worker annually
` workers in Group A, and every two thereafter.
' months on those in Group B, at the time of the periodic screening and urine ex- INTERIM PHYSICAL EXAMINATIONS
i
animations. When significant abnormal-
The frequency and extent of interim
f ities are found in the blood smear, it physical examinations of workers by the
j should be repeated in one week,
plant physician will be determined by
j A red blood cell count, white blood his review and analysis of the "screen
j cell count and hemoglobin determination ing" records of the individual workers,
1 should be done every three months on in accordance with the schedules pre
each worker in Group A, and every six viously discussed.
months on each worker in Group B.
Workers whose records indicate ab
normalities should be given careful and
;
RECORDING OF RESULTS
complete physical examinations by the
A standard form should be used for plant physician. When necessary, labo ! each worker giving his occupation, place ratory tests should be repeated, or other
I of work and group classification. In per laboratory data obtained as indicated. il sons showing unusual susceptibility, an Quantitative determinations of lead in
y individual classification of the worker the blood may be extremely helpful in
f may be desirable. This may differ from differential diagnosis.
I that of his group. On this form, the re-
| suits of each screening examination
LABORATORY STANDARDS
should be checked off, and all laboratory findings should be entered. This form should be made a part of the confiden tial medical records of the plant.
The presence of significant, hemato logical abnormalities such as stippling, changes in the color or morphology of the red blood cells, or a drop in the
PRE-PLACEMENT AND ANNUAL PHYSICAL EXAMINATIONS
hemoglobin, particularly when persis tent, should be considered as a warning of incipient intoxication. The values of
Upon institution of this plan of med 0.1 mg. of lead per liter of urine, and
DUP050314423
68 SILSON
0.07 mg. of lead per hundred cc. of whole blood are generally considered the upper limits of "normal" for lead workers. Variations from the "normal" are common and can be interpreted only in conjunction with all of the clinical findings on physical examination. The laboratory provides valuable aids to di agnosis. It is not, however, a substitute for good clinical medicine.
the basis of subsequent examination. Of course, where an instance of lead poisoning is due to deficient controls, it may be possible for the worker to con tinue at his job as soon as effective con trols are instituted. In cases showing unusual susceptibility to lead, it may be necessary for the worker to avoid com pletely all further exposure to this in dustrial hazard.
INTERPRETATION OF FINDINGS
PLANT CONTROL
In evaluating the findings in a given case, considerable weight should be given to trends, such as a progressive increase in pallor, tremor, weight loss, constipation, headache, hematological abnormalities including stipple cell count, or urinary lead excretion. A lead line indicates storage, not intoxication. The development of intercurrent disease, whether or not it is the result of lead exposure, should be given special con sideration by the physician -- particu larly those conditions which tend to make the worker more susceptible to the injurious effects of further exposure. The final interpretation of the case and the decision as to what to do for a given worker will depend upon a careful evaluation of the entire medical picture, which includes both clinical and labo ratory data.
RECLASSIFICATION OF WORKERS
Workers in Group B who show labo ratory evidences of increased lead ab sorption without lead intoxication should be reclassified as Group A, and followed even more closely if necessary. Any worker showing symptoms or signs of lead intoxication should be immedi ately transferred to a lead-free job, or one with minimal exposure. When, if ever, such a worker may be permitted to resume his regular work should be determined by the plant physician on
In addition to serving as a check on the individual worker, this screening program affords an excellent cheek on the engineering and sanitary control of the plant as a whole. The plant physi cian, carefully reviewing his medical findings by occupation and department, is frequently in a better position than anyone else in the organization to spot a breakdown in controls or an unusually hazardous type or place of work, and to recommend additional controls be fore serious illness results. Where a definite rise in lead absorption or lead intoxication occurs in a group, investi gation of the working conditions of that group should be instituted at once. This should include, air studies for lead. Wherever possible, atmospheric lead concentrations should be kept below the safe accepted standard of 1.5 mg. per ten cubic meters of air.
EXPERIENCE WITH THIS PLAN IN NEW YORK STATE
It is still too early to evaluate how successfully this plan is functioning in New York State. The program was only drawn up a little over a year ago, and at that time, the problem of urinary lead determinations on a large scale was still a deterrent to its practical applica tion in some plants. The incorporation of the Cholak technique into the plan has materially improved its feasibility
MEDICAL CONTROL
69
i since. By and large, it has been well mum of coveralls and a cap, and where
r: received in the plants where it has been contamination is very heavy, under
r proposed, particularly in the larger ones clothes and socks as well. These clothes
; where a medical office is already in exist- should replace the workers' street clothes
| ence. Some of the many smaller plants and not be worn over them. Provision
f have difficulty in getting a medical set- should be made for laundering them at
| up organized, and in arranging for the least weekly, and more often, up to
laboratory work. We hope in the next daily, if necessary. In order to achieve
* year or two to review the findings in the these objectives, the plant management
. plants which have adopted it, to see may find it advantageous to supply the
f whether a program such as this can be necessary garments to the workers and
j of material assistance in improving con to launder them as often as the indi
; trol and cutting down the incidence of vidual situation warrants.
; lead poisoning.
In addition, all lead workers whose
shoes become heavily impregnaled with | PLANT HYGIENE AND SANITATION lead materials should be provided with
Another phase of the problem of medical and required to wear suitable protective control of lead workers involves the footwear while on the job, which will sanitation and hygiene facilities of the not be worn home. Those engaged in the plant. Workers exposed to lead fumes, handling of lead materials in a wet state ' dusts and solutions tend to accumulate should whenever possible, wear protec ; the material on their persons, their hair tive gloves and aprons.
S and their work clothes. When special
; precautions are not taken, they will
LOCKER ROOMS
!
carry this material home with them. This
Double locker rooms, with an inter
subjects the worker to additional ex- vening lavatory, should be provided for
j posure during his non-working hours,
i
both male and female lead workers. The Furthermore, the possibility of ingestion first locker room, designated as the
| of lead, though of secondary importance, "clean" room, is where the worker dis
exists when adequate drinking and lunch robes on arrival. From it, he passes
room facilities are not supplied. It is,
through the lavatory to the "dirty"
therefore, essential to make special pro room, where his work clothes are kept.
vision regarding work clothes, locker At quitting time, he can then remove his
rooms and eating and drinking facili- contaminated clothes in the "dirty"
j ties, to prevent contamination of street room, shower or wash thoroughly, and
i it I
clothes, and to minimize exposure during lunch hours. Along these lines, the
dress in the "clean" room without dan
| Division has operated on a number of ger of contaminating his street clothes.
Access to the "clean" room should be
n principles outlined below, which it rec possible without passing through con
ommends to those industries where they taminated areas of the plant; and simi
are applicable.
larly, it should be possible for em
WORK CLOTHES
ployees, in their work clothes, to pro ceed to and from their jobs without con
All lead workers should have available taminating offices and other clean areas
at the plant special clothes into which they can change before starting work. These clothes should consist as a mini
of the plant. Both locker rooms should be designed
to afford maximum ease of cleaning.
J
DUP050314425
70 SILSON
The floors should be of waterproof ma terial, with sanitary bases, sloped and drained so that they can be hosed or scrubbed down readily. Lockers should have tightly closing doors with louvres or other ventilation. They should have inclined tops, and the bottoms should be continuous with the sanitary base of the flooring, to prevent dust from settling on them or collecting underneath. Sepa rate toilets should, if possible, he avail able to the "clean" and "dirty" locker rooms. All plumbing facilities, benches and other equipment should be so de signed that they can be readily cleaned.
WASHING FACILITIES
As was previously mentioned, the New York State Labor Law, through the Code Bulletins promulgated under it, specifically requires special washing fa cilities where lead or other toxic ma terials are handled. A minimum of one wash basin or its equivalent, equipped with running hot and cold water, must be provided for every ten employees. In addition, soap and individual towels, which may be of paper, are mandatory, and it is advisable to supply nail brushes and special cleansing agents where necessary.
All lead workers heavily contaminated in the course of their work should shower every day before leaving the plant. All others should wash thorough ly all exposed parts of the body after removing their work clothes and before dressing. They should be advised to bathe and wash their hair at least twice a week. Washing or showering should be done under factory supervision, and at least ten minutes should be allowed at the end of each shift for this pur pose. A minimum of one hot shower should be provided in every lavatory for emergencies, with additional ones on
the basis of one for every five workers requiring daily showers.
LUNCH ROOMS
As stated earlier, the New York State Labor Law provides that in all indus tries handling lead, the workers are not permitted to bring into or eat in the workroom any food, that a notice to this effect must be posted, and that some place for them to eat their food must be provided. While theoretically, space set aside in a locker room fulfills these re quirements, it is not a satisfactory solu tion, because, with the set-up described above, the workers would either have to eat in the "dirty" room, where their food could become contaminated, or else in the "clean" room, which would re quire them to shower and change their clothes to avoid contaminating it. Since it is inexpedient for them to do this at lunch time, lunch room facilities should be provided for all the workers, wher ever possible.
The type of facility would vary with the size of the individual plant and the habits of its workers, ranging from a room in which to eat lunches brought in, to a full cafeteria service. The room should be constructed with waterproof drained floors, sanitary bases, and readily cleaned tables and benches, so that it can be hosed down after each meal period. Workers should not be permitted to return to the "clean" locker rooms during lunch hours: to this end, a cubbyhole for each worker should be provided in or near the lunch room in which he can leave his lunch on ar rival in the morning. Unless the lunch room is located sufficiently close to the locker rooms so that the latter's facilities can be utilized, a separate wash room should be provided adjacent to it. It should not be located where contamina tion from the workrooms is likely. In
II .H ,. ^
T
I
DUP050314426
MEDICAL CONTROL
71
larger plants, the lunch room is some unit should be set up, from which the
times placed adjacent to a yard or other respirators would be issued daily or as
enclosure in which the workers can eat required, and collected, cleaned, steri
their lunch or relax out-of-doors, if they lized, tested, and if necessary repaired,
so desire. It is recommended that, as a ready for reissue. When a worker re
minimum, a dispensing machine for quires one constantly, he should be pro
beverages, preferably milk, be provided. vided with two, which are exchanged
1 Efforts should be made to discourage daily at a fixed time under proper con
the workers from eating in neighbor trol. A convenient arrangement is to
hood lunchrooms in contaminated put the respirators into individual paper
clothing.
bags, identified for each worker, after
An abundant supply of drinking maintenance has been performed. The
water should be maintained by the use maintenance and issue of respirators
of angle jet fountains. Where these should be under the direct supervision
cannot be provided, water should be of the medical department or the safety
supplied outside of any workroom where engineer. When respirators are used
lead processing is done, and individual intermittently by the workers, they will
paper cups should be furnished.
as a rule leave them suspended about
RESPIRATORS
their necks when not in use. Frequently, this results in contamination of the in
While the Division does not in general side of the respirator from contact with
approve the use of respirators as a means lead-impregnated work clothes. To re
of control, there are certain special cir duce this to a minimum, it is recom
cumstances where they must be used, mended that the worker be issued a
either because engineering controls are plastic bib against which the respirator
impossible for the particular operation, can rest. The smooth surface will shed
or because the operation is so infre dust more readily than the work clothes,
quent as to make elaborate ventilation and can be kept clean more easily.
unfeasible. In addition, in certain in stances, respirators may be required in APPLICATION IN NEW YORK STATE
addition to engineering controls. Air
In the application of these principles
line respirators are indicated whenever to various plants and industries in
the exposure is heavy or work is done New York State, considerable flexibility
in a confined space, as for example, is allowed, and each instance is treated
when cutting red-leaded steel in a ship's as an individual problem. The extent to
hold; for lower exposures, a cartridge or which each of these principles can be
canister type of respirator approved for applied in a particular plant is discussed
the particular nature of the lead ex with the management, and a program
posure, such as dust, fume or mist, may agreed upon which is both feasible and
be adequate. Maintenance and cleaning adequate. Moreover, since many of
men especially, whose work carries them them are merely recommendations, and
all over a plant and into areas where not enforceable by law, we try to demon
the local or general ventilation may not strate how their adoption will be of
be effective, should be protected in this benefit to die industry. The following
way.
examples illustrate our approach:
When respirators are used, their main
An ideal opportunity presented itself
tenance should not be left to the indivi when we were approached by a com
dual worker. A centralized respirator pany manufacturing pottery decalco-
DUP050314427
72 SILSON
manias to help them plan for the con- extremely accurate, it is necessary to
trol of the lead hazard in a new plant air condition the press room to avoid
they were in process of building. Al- changes in paper size due to varying
most all the pigments used in printing temperature and humidity. The com-
tfaese decals contain lead borosilicate as pany had planned to recirculate all of
a flux and some, in addition, contain the air for this reason, but the Division
other lead salts as a basic color. The felt this to be inadvisable. Studies were
majority of them are dusted onto the therefore made on the presses, dusters,
sheets after printing the pattern in var- and brushes in the old plant, and local
nish, and the excess powder is then ventilation designed which would reduce
brushed off after the varnish has dried, the air contamination with a minimum
Although lead borosilicate is considered volume of exhausted air. The duct sys-
less toxic than some of the more soluble terns and collectors were then integrated
salts, the dusty character of these opera- into the plans for the new building,
tions still creates a real hazard requir- It was agreed to recirculate none of the
ing careful controL
local exhaust air and a maximum of
The company roadily accepted our 20% of the general room air, and pro
suggestion to set up a program of medi- visions to condition an adequate amount
cal control in accordance with the pre- of make-up air were therefore included,
viously discussed outline, and a medical Another special problem came to the
oESce with adequate space and facilities attention of the Division through a case
for putting such a program into effect of lead poisoning in a newspaper stereo-
was incorporated into the building typer. The plant in which he worked
plans. In addition, numerous alterations was a clean and up-to-date one, which
were made in the layout of the locker would normally not have been sus-
rooms to conform to the above sugges- pected. Air tests made in the breathing
tions, and a lunch room, which had riot zones of the workers revealed values
been projected, was included in the re- two to three times the maximum allow-
vised plans. After much discussion, it able concentration for lead in the
was decided that the lead contamination breathing zones of the workers at all
was not sufficiently great to warrant operations. Further studies then showed
, compulsory showers, but one shower the lead in the general room air to be
for emergencies was included in each uniformly high, and determinations
I lavatory. Double locker rooms, in place made at the possible points of origin
of a larger single one originally planned, indicated that this was due, not to fumes
. . were designed, with entrances so ar- from the melting pots or pouring opera-
1 ranged as to avoid contamination of' tions, as was first suspeoted, but to fine :
clean areas of the building. A larger particles dispersed in the air by the cut-
number of washing facilities than had off saw on the caster. A special means
been originally thought necessary were for locally exhausting this saw is being
also included.
'
' devised, and a program of medical
In addition to the medical and sani- examinations for the workers has been
' tary aspects, the Engineering Unit of recommended to the company,
the Division was able to supply consid- Still another case of lead poisoning -
erable assistance in planning the ven- was reported in a worker in another
tilation controls in the new plant Since plant who was spray painting the backs
each color is printed with a separate of mirrors with a special lead-containing
press run, and superposition has to be paint Here the exposure was due to
.
DUP050314428
MEDICAL CONTROL
73
faulty design of the spray booth. Re design of the booth, and the additional use of cartridge respirators proved to be the solution; and arrangements were made with the plant physician for a periodic medical check-up on all the ex posed workers.
CONCLUSIONS
In conclusion, then, the New York State Division of Industrial Hygiene and Safety Standards has prepared an integrated program for the medical con trol of lead workers. A system of peri odic screening examinations under medi cal supervision is recommended, which includes an evaluation of symptoms, a limited physical examination, and blood and urine tests; and in addition, a com plete examination by the plant physician at least annually. This serves as a check both on the individual worker, and, by analysis of the data by groups and de partments, on the occupation and work room. Further recommendations have been made for special considerations in planning locker and lunch rooms, and for a well-rounded program of individ ual and plant hygiene. A means for safely using respirators when necessary
has been proposed. By and large, this program, when combined with proper engineering controls to remove most of the lead at its point of origin, and peri odic air tests to check the efficiency of operation, should enable a plant to re duce the incidence of lead poisoning to that of a rare phenomenon, and to im prove the health and morale of all its workers.
Ch a ir ma n Bo w d it c h : Our next and final speaker of the afternoon has been selected to lead the discussion of Dr. Silson's paper because of his long and important connection with the Connec ticut State Department of Public Health, where he was industrial hygiene chem ist from 1928 to 1937.
During that period, he was chairman of the Engineering Committee of the National Silicosis Conference, and more recently has been chairman of the Com mittee on Determination of Atmospheric Contaminants of the American Public Health Association. He is now director of the Division of Industrial Hygiene and Engineering Research of the Zurich General Accident & Liability Insurance Company. Mr. .Warren A. Cook.
DISCUSSION
Mr . Wa r r e n A. Co o k [Director, Di vision of Industrial Hygiene and En gineering Research, Zurich General Accident and Liability Insurance Co., Ltd., Chicago, Illinois]: With the in corporation of all the elements outlined in the medical control program pre sented by Dr. Silson, I think we will agree that the possibility of development of lead poisoning would indeed be low. There are a number of points, however, which I feel might be introduced to
increase the practicality of such a pro gram.
Frequencies of periodic examinations of workers, their blood and their urine, were presented, based upon the occu pation or operation involving the lead exposure. This should serve as a valu able guide. However, the results of one or two initial series of such tests should influence future frequencies of them. Assuming negative results from the physical examinations and blood tests,
DUP050314429
74 DISCUSSION
the magnitude of the exposure as indi use of air line respirators, or other con
cated by concentration of lead in urine trol measures.
'
serves as a better criterion of preferred
In the matter of work clothes, the
frequency of all these examinations than wearing of gloves was mentioned in
can any fixed schedule.
handling wet lead compounds. If Dr.
For example, spray painters were Silson had in mind skin absorption of
listed in classification A. Spray painters lead, I assume that he was referring to
may be exposed to a small amount of organic lead compounds such as lead
lead, where the lead' may be present tetraethyl inasmuch as we need not be
only in the proportion of Vs percent as too concerned about skin absorption of
a drier. Or we may have an olive drab inorganic lead compounds whether wet
paint with 7 percent lead chromate, or or dry.
the paint be red lead itself. Certainly,
In discussing the matter of respir
we would not feel that a worker who is ators, cartridge respirators were men
spray painting in front of a well-ex tioned. Though these are in order for
hausted spray booth, with a paint which solvent vapor protection, filter type res
might contain V> percent of lead naph- pirators are more effective for lead dusts
thenate as a drier should be examined and fumes.
_
at the frequency required under classi
In regard to maintenance of respir
fication A.
ators, one of the best procedures is that
On the other hand, if spray painters published by the industrial hygienist of
happened to be removing red lead paint the Allis Chalmers plant at West Allis,
with a power-driven scratch brush in a Wise., in the March, 1948 issue of the
confined area prior to painting, an early American Industrial Hygiene Associa
examination might show sufficiently high tion Quarterly. This covers both the
exposure that a second series of tests cleaning and the sterilizing and handling
would be indicated within a week. of respirators from a maintenance point
Schedules should certainly be set up as of view.
outlined by Dr. Silson, but these should
It should be emphasized that the great
be shifted one way or the other accord importance of lead-in-urine analyses in
ing to the exposures of the individual the lead hygiene program is that of a
group.
control measure. The real value of these
As a recent example, we wanted to be analyses is to determine whether the
certain that there was no excessive lead worker is exposed to enough lead to
exposure in cutting up some of the cause lead poisoning, rather than to de
LSTs and DE's that were built during termine whether or not he may have it
the war. Our general information was after he has been heavily exposed.
that the shipyards had used zinc chro
As to whether the worker should be
mate primers and only the small percent told what his lead-in-urine result is, I
of lead for the driers in the gray finish feel, personally, that the local situation
coats.
should govern the decision. The attitude
To our great surprise, on checking of the individual group of workers and
the paint chips from a number of DE's, their relation toward management, the
we found from 8 to 20 percent lead. number of them, what you expect to,
We accordingly started with a high fre find and what you expect to do with the
quency of lead-in-urine analyses to de lead-in-urine results are all factors.
termine whether the exposure to lead
Our experience in certain other plants
could be kept to satisfactory limits by has been that the lead-in-urines can be
DUP050314430
MEDICAL CONTROL
75
used to enlist the greater cooperation of the individual worker.
For example, in one spray painting department where lead chromate was being used on large machinery, lead-in urines were run. At the end of one month, we collected another set of urine samples. The workers were very much interested in the results of the first samples.
We indicated that one test didn't mean too much, but told the men that the results were low or average for such work according to the results. In one case where the result was high, we told them that this one test did not mean that his health was affected but it did mean that he should reduce his exposure or he would be getting too much lead and might develop symptoms if he continued to breathe in too much lead over a period of time. We inquired whether he was wearing his respirator all the time, or whether he carried it on the side of his face. Did he make sure not to get in line with some other operator's spray gun and was he careful to avoid working between the parts being sprayed and the exhaust ventilation.
We took another group of samples at the end of the next month, and every one of them was well down. We length ened the frequency to a quarterly period, but did not further extend the period because we felt that at any time the workers could get careless and over expose themselves. Thus we let both the type of work being done and the results that we had obtained fix the frequency of the lead-in-urine determi nations.
In discussing a medical program in industry, I should not fail to express an opinion which is very firmly fixed with me, and. I am sure with most indus trial hygiene people. Whereas we may place much emphasis on the laboratory and technical phases of a lead hygiene
program, we also insist that medical control is an essential.
Ch a ir ma n Bo w d it c h : Mr. Cook made reference to paints used by the Navy. I wonder if Dr. Brown would care to comment on what Mr. Cook said on this subject.
Dr . Er n e s t W. Br o w n [Council on Industrial Health, American Medical Association, Chicago, 111.]: The later methods of control?
Ch a ir ma n Bo w d it c h : No. He spoke of the nature of the paints that were used on ships. Would you perhaps re peat what you said about this, Mr. Cook?
Dr, Brown, of course, was in charge of industrial hygiene research in the Navy during the war.
Mr . Co o k : I am very glad Dr. Brown is here to give us the answers on the lead paint on these ships. On the LST we found only 0.45 percent lead as the naphthenate in the drier. On the super structure and various other parts of the LST, there were similar low percent ages.
On one DE, we found 20.6 percent lead. A second DE ran about 21 percent and three others gave 8, 16 and 15 per cent lead. -
Since the only lead in the paint used on Navy ships in the yards with which we had contact during the war was the half a percent used in the drier, your information on the probable source of litis lead paint would be of very great interest.
Dr . Br o w n : Yo u probably know, Mr. Cook, that the Navy abandoned the use of lead paints officially in December, 1941 and went to another pigment from that time, namely zinc chromate.
The DE type of boats were built during the war period; therefore, should have been painted officially with another type of paint and not with lead paint.
I think, however, there was some
DUP050314431
76 DISCUSSION
bootlegging in regard to red lead paint, despite the official instructions from headquarters. I know that a certain number of ships did get red lead on them.
Dr . Le o n ar d J. Go l d w a t e r [Pro fessor of Industrial Health, School of Public Health, Columbia University, New York, N. Y.]: In our experience, we found the only time we ran into lead paints was on ships of foreign countries which were here for repair, particularly British ships. When they came in and needed some burning or cutting or weld ing done, we had to watch out for lead poisoning; in fact, we saw some cases of lead absorption, but not on the ships of our own Navy. It may be that some of those that Mr. Cook has run into were at some time in foreign yards for over haul or repair and got some British or French or some other kind of lead paint on them, but the Navy, just as Captain Brown said, had practically no lead paint.
Dr . Br o w n : I would like to add another point. While the Navy discon tinued the use of red lead paint in De cember, 1941, it authorized the con sumption or using up of all stocks on hand, which probably were extensive, involving quite a considerable carry over. [Laughter]
Ch a ir ma n Bo w d it c h : As one of our outstanding veteran state industrial hy giene administrators, I wonder if Dr. Gray would like to add anything to the discussion of Dr. Silson's paper.
Dr . Al b e r t S. Gr a y [Director, Bu reau of Industrial Hygiene, Connecticut Department of Health, Hartford,Conn.]: There is nothing I care to add, Mr. Bowditch, except to emphasize -that medical control is a very big factor in this whole story. We utilize it in Connecticut, and it has been shown very definitely that it checks up the engineering and it checks up the carelessness of the individuals
who are working in these lead industries. It is very necessary, I think.
Ch a ir ma n Bo w d it c h : Are there any further comments?
Mr . G. C. Wa l t e r s [National Lead Co., Chicago, 111.] : I would like to ask Dr. Silson about his comment on the spot sampling for urine, because of con tamination of a more elaborate sample. Do you mean the sampling within the plant?
Dr . Jo h n E. Sil s o n : We feel that, for frequent checks, spot samples are quite adequate and the most simple to collect. If a larger specimen is wanted for re check, then we like to see off-the-job samples collected; 24 hours, over Sun day, when the worker is not working; or maybe two or three nights at home, without collecting the daytime samples while he is in the plant. But to have them collect a 24-hour sample during die work week, we feel, brings up too great a danger of contamination. The worker has to carry a botde with him, and he almost invariably contaminates it.
Mr . Wa l t e r s : I wondered how Dr. Belknap gathered the 24-hour sample. Have you any absolute way of knowing it is the urine pf the man in question? Do you gain better results by having a 24-hour sample than you would by a spot sample?
Dr . Be l k n a p : Well, we have no guar antee, of course, that it is not a sample of the entire family [laughter] while the man has gone fishing over the weekend. But, just like anything else, in evaluat ing a man's symptoms from frequent re-checks if you know the man per sonally you can tell pretty well whether he has been cheating on this urine . proposition.
It just seems to me that, when one is dealing with millionths of a gram, really of lead, even in a liter sample, of 2,000 ce. sample, you would have less error if you studied a larger sample
DUP050314432
MEDICAL CONTROL
77
than a spot sample. The problem may be a medico-legal one. I simply would like to say, in regard to this urine lead study, that I have no. quarrel with col lection of urines. I think we are going to learn a lot more in the procedures as suggested by Dr. Silson, using the Cholak method, and Dr. FairhalPs short method can probably be used also. But we have to have something to tell a man who has the idea that he has lead poi soning, or his doctor has told him that he may have lead poisoning. That is the problem. You can eventually, by your engineering technique and air con trol, have your air concentration and your resultant urine lead down to within safe limits, but you still have the psy chology of the patient who knows that he is working with lead and fears it in any amount. The hemo-stippled cells and lead line of the gums are quicker to
determine and more diagnostic than urine leads done regarding actual lead intoxication.
Unless you have something specific that you can say whether or not he has anemia, or whether he has a lead line, stippled cells or any other evidence of possible lead absorption or lead intoxi cation, then you are at the mercy, really, of the man's family doctor. In many cases, if the family doctor is well in formed, you can rely on his cooperation. However, there are instances where you cannot afford to let the family physician merely speculate regarding lead absorp tion versus lead intoxication.
Ch a ir ma n Bo w d it c h : We have run well beyond our closing time and I should therefore postpone further dis cussion of stippled cells versus urine until after lunch tomorrow. We stand adjourned.
DUP050314433
DINNER SESSION
November 16, 1948
Pr e s id e n t Wo r ms er : Our guest of honor and speaker of the evening is a graduate of Cornell University, Class of 1918, where his athletic prowess earned him recognition as an All-American tackle. He has continued his interest in sports, particularly football, as an ad viser to the Chicago Bears, and is an amateur aviator. His entire professional career has been spent with the Inland Steel Company, and LIFE recently re produced his photograph as an excellent
illustration of a self-made man who has worked his way up to the top from hum ble beginnings, and of what can be done by Americans under our system of free enterprise. With his vast experience in handling men, I am sure you arc in for a treat in hearing his views on industrial health. I take great pleasure in present ing to you Mr. Fred M. Gillies, Works
Manager of Inland Steel Company's In
diana Harbor Works.
THE PRODUCTION MANAGER LOOKS AT INDUSTRIAL HEALTH
By FRED M. GILLIES
IForIts Manager, Indiana Harbor Works, Inland Steel Co., East Chicago, Ind.
The industrial progress of America is controlled completely by two men. One is the production manager--the other the worker.
Modern industry requires both ma chines and men. Machines must be de signed by men and they can not produce without operators. Machines must be serviced by men to be kept in efficient operating condition. So no matter how ingeniously we design machines, we still must devote most of our attention to the men who operate and service them. We cannot design men like we do machines, we have to take them as God gives them to us, but we can care for these men, and see to it that they operate efficiently. Here is where the production manager comes into the picture.
Somehow, there has been developed a feeling that productivity in America has expanded at the expense of social jus tice. Also, the idea has been advanced that human problems are increasing due to industrial pressures. We believe these assumptions are false. An unjust social
situation and unfair standard of human values could not possibly give America the production record it enjoys today. And, as for social problems increasing, that may be true to some degree, in so far as the population is increasing, but is more reasonably explained by the fact that we are today more aware of social problems, just as we have become more aware of the early signs and symptoms of cancer and other diseases.
During 1948 the index of production per man hour is approximately 30 per cent greater than it was ten years ago, and it is about 60 percent greater than it was 20 years ago. It is not unusual today for production to exceed 100 per cent of rated capacity. In buying power a United States worker makes more than twice as much as a British worker, un der a Socialistic government; and ten times as much as a Russian worker, under a Communistic system. Somehow, as a production manager, I cannot quite see how we compare unfavorably with the rest of the world in matters of social
78
PRODUCTION MANAGER LOOKS AT INDUSTRIAL HEALTH
79
justice, human values, and personal hap piness.
The degree of production depends en tirely upon men. The production that men may deliver is directly related, among other things, to the state of men tal and physical health. For that reason, industry is interested in maintaining good health in its workers. However, progressive industrial leaders feel that production should not be the sole reason for an interest in the health of workers. The merit of the humanistic attitude is clear to all of us today.
It is quite apparent that industrial medical service can not and should not do the whole job of looking after the health of its people, and it would be impossible to do so even if industry wanted to, because of such factors as weather-, epidemics, domestic problems, etc., all of which play their part. How ever, industrial medical service can go a long way toward the ideal by providing an ethical medical program suited to the particular needs of the industry.
In the interests of production, indus try should have the answers to several questions:
Is the health of the worker suitable to the job?
Does the worker maintain that degree of health as he continues to work on the job?
Is the environment in which he works safe and healthful and reasonably free from annoyances?
Does the worker understand how to keep himself in a healthy state?
The answers to these questions can be provided only by the doctor and hy gienist. When greater production is called for in our normal competitive scheme of things the production man ager should get better results if he has made it a practice to interest himself in the health problems of the worker.
Naturally, at this point there might be some question that this would be more effective for morale than an increase in pay. It has been said that if the indus trialist could forget about profits, the workman forget about pay, and the poli tician forget about votes, our troubles would be over.
The production man naturally believes in private enterprise, and it follows that he is interested in how much and how far medical and hygiene services are to be extended to employees. Because a thing works well, there is often a tendency to over-do it In the case of industrial med icine and hygiene, the production man ager feels that the same principles that apply to private enterprise should apply to medical services within industry.
Briefly such services should probably include:
Medical and surgical services for those who are injured or made ill by their jobs.
Emergency services, within ethical limits, for non-industrial illnesses or injuries.
Pre-employment and periodic physical examinations.
Industrial hygiene surveys and serv ices within the industry.
General health education and advice.
All other things, including the treatment of non-industrial illnesses and disease, preventive medicine and public health, should properly lie outside of manage ment.
Although the industrial medical de partment should cooperate with public health agencies and private practitioners and assist wherever possible in commun ity Health programs, the prerogatives of such agencies should not be infringed upon by the industrial doctor or hy gienist The reverse situation should hold equally well.
DUP050314435
80 GILLIES
In administering such a program, it is probably well to remember that the in dustrial doctor and hygienist are trusted representatives of management, whose chief interests are in maintaining the health of all employees, including those in management.
It has occurred to me that the indus trial doctor and hfgienist perform a very valuable and important function in the labor and industrial relations pic ture, directly or indirectly. The intimate problems of personal health and happi ness can not be adequately discussed and solved anywhere as well as they can in the privacy of the doctor's office. This is especially true if management respects the confidential relationship, which must
exist between the doctor and the em ployee.
In our busy world of today, which is becoming very crowded and where life has become more complex, it is neces sary for the industrialist in charge of production to step back from time to time and take a look at himself in sharp and candid focus. He should examine the philosophy of his daily life and the things he does to see if he is contrib uting something to relieve the fears and bitterness which beset and plague us.
The sincere and friendly interest that modem industry is taking in the health of its workers will help in a large way to dispel some of the conflicts that have existed in the past.
!
i
DUP050314436
TUESDAY MORNING SESSION
NOVEMBER 16, 1948
Ch a ir ma n Bo w d it c h : Our first paper this morning will be by a man who was Acting Chief of Research of the U. S. Food and Drug Administration during the war and is now Scientific Director
of the Research Branch of the National Cancer Institute. On the basis of his very extensive animal experimentation with BAL, Dr. Harry Eagle will speak on "The Effect of BAL on Experimental Lead Poisoning."
THE EFFECT OF BAL ON EXPERIMENTAL LEAD POISONING
By HARRY EAGLE, M.D.
Scientific Director, Research Branch, National Cancer Institute, Bethesda, Mi.
BAL was developed in the early days of the war by a group of inspired Brit ish investigators under the leadership of Dr. Peters, Dr. Stockton and Dr. Thomp son, primarily for the treatment of po tential injuries caused by the arsenical war gases.
I will not detail the events that led to the development of this compound, other than to say that it began with the almost chance observation that when certain toxic arsenicals were allowed to react with tissues, they combined with twice as much tissue sulfhydryl groups as they should have on the basis of the then ac
cepted ideas as to the mechanism of the reaction between arsenical and tissue SH groups.
In the top right-hand corner of Fig. Is is the chemical structure for BAL 2, 3dimercaptopropanol.
This was only one of many com pounds which were synthesized and found able to compete with the tissues for the possession of arsenic. Even after an arsenical war gas had reacted with and combined with tissues Land pre-
*The figures and-tables included in this manu script have been reproduced from a number of previous publications listed on page 91.
Fig. 1--The top right-hand corner is the chemical struc ture for BAL 2, 3-dimercaptopropanol and in the top left-hand corner is the tissue-arsenic compound formed after arsenical war gas had reacted and com
bined with tissues.
Ji DUP050314437
82 EAGLE
sumably with sulfhydryl groups in those animals which had already gone on to
tissues] to form a tissue-arsenic com develop systemic evidence of arsenic
; pound which is illustrated in the top poisoning. For example, we injected left-hand of Fig. 1, the BAL could com some rabbits with mapharsen at 20 mg.
pete effectively with the tissue sulfhydryl per kilogram which in man corresponds
groups for the possession of the arsenic to about 1200 mg. and which is reg
to form a Bal-dithioarsenite. Monothiols, ularly fatal. The rabbits immediately
such as cysteine and glutathione which developed signs of distress, vasodilata
were far less effective than these dithiols tion, dyspnea, and died within a short
in competing with tissue sulfhydryl time. If, five minutes after the initial
groups for the possession of the arsenic. injection of mapharsen, and when the
During the war, also, Dr. Barron and animal was already in acute distress, it
a number of others in this country was given an injection of BAL, there
showed that arsenicals generally were was a spectacular recovery, and within
able to inactivate a large number of en half an hour. This makes for a striking
zyme proteins containing sulfhydryl classroom demonstration.
groups, and that BAL could reverse the
Under the microscope, if one takes a
inhibitory effect of arsenicals [and also suspension of, for example, trypano
of mercury compounds]. It seemed somes, which are extremely sensitive to
probable that the toxic effects of arsenic most of the trivalent arsenicals, and adds
on tissue was due to the fact that they one of these arsenicals in sufficient con
combined with and thus inactivated cer centration, the organisms are immobil
tain sulfhydryl-containing enzyme pro ized almost instantaneously. Within a
teins in tissues, and that the reversal of few minutes any one familiar with
that combination hy BAL was the basis their microscope appearance would say,
of its therapeutic action.
"These are dead organisms." They have
When it was originally developed, become globular and vacuolated, and
BAL was first thought to be of value have swollen to about twice their nor
merely as a local antidote to the skin mal size.
and eye injuries caused by Lewisite,
if, at that point, one adds a little BAL
Adamsite, and the other toxic arsenical in solution on to the slide, the trepano-
war gases which were used, to limited somes, like Lazarus, rise from the dead
degree, in the first World War, and on and resume their normal, elongated
which there has been some study in the form, and become actively motile. This
intervening period.
also makes for a pretty laboratory dem
Fortunately, the use of the arsenical onstration.
war gases did not materialize in this
Table I illustrates this resuscitating
war, and the use of BAL for the treat experiment. If one adds some BAL to a
ment of certain types of metal poison suspension of "killed" trypanosomes,
ing, has thus been a by-product of a less than one minute after the ; rldition
war scare.
of the arsenical, more than 95 per cent
It soon developed that the favorable of the organisms are resuscitated by as
therapeutic effect of BAL on gas poison little as iy% molar equivalents of BAL.
ing would not be limited to its local
The longer one waits from the time
effect on skin areas or eye areas which of the addition of arsenic to the time of
had been damaged by contact with revival by the addition of BAL, the less
these gases. Even when BAL was given successful the results. Thus, after 30
systemieally, it had favorable effect on minutes, only around 10 per cent of the
DUP050314438
u
BAL
83
organisms are revived, no matter how much BAL was added. By that time a fair proportion of the organisms had al ready lysed, and tlieir resuscitation would involve reassembling the organism.
The right-hand portion of the table shows that, in this respect, cysteine and, indeed, any monothioj, is far less effec tive than BAL. To revive 95 per cent of the organism with cysteine, for exam ple, required 1,250 molar equivalents, instead of 1%. That is a measure of the far greater affinity of the dithiol for the arsenic.
The effect of BAL in counteracting systemic arsenic poisoning is due to the fact that it can compete successfully with a tissue dithiol group for the possession of arsenic. This is shown in Table II. Trypanosomes combine with arsenic, and are able to concentrate some of these toxic arsenicals to an extraordi nary degree, so that the concentration of arsenic in the organisms is 100 and even 200 times greater than in the surround ing fluid. The figure in the last column of the table is the ratio of the concen tration of arsenic in the trypanosomes to its concentration in the surrounding fluid.
If, to such a suspension, one adds some BAL, the drug abstracts the ar senic from the trypanosomes and strik ingly reduces the concentration of ar senic in the trypanosomes relative to that in the fluid, e.g. from 257 to 28.
In another experiment with phenyl arsenoxide the hydrolyzed form of one of the war gases, the ratio of concentra tions was reduced by cysteine acting in concentration of 0.01M from 143 to 33, but, by BAL, in one-tenth that concen tration, down to nine.
I should say at this point what BAL stood for. When the material was still in the secret category some of our col leagues learned enough about it to spec ulate that BAL might stand for bismuth, arsenic and lead [Laughter]. This was, in the light of what we now know, a very
shrewd guess indeed. Actually, BAL stood for British Anti-Lewisite, because it was first developed for the treatment
of lewisite poisoning. Those of us working with the com
pound--I am sure Dr. Corwin would subscribe to this--were always a little puzzled at the secrecy which surrounded the material. It required little more than a sub-average sense of smell and a
TABLE I The Resuscitation of Arsenic-Poisoned Trypanosomes by BAL and by Cysteine
Trypanosomes were completely immobilized in one minute by the addition of phenyl arsenoxide to T 0~5 molar concentration. Sulfydryi compounds were added at Ihe intervals and in the amounts Indicated.
Time organisms exposed to
arsenical before addition of
--SH compound
< 1' 5'
15'
30'
Molar equivalents of -SH compound added
'
BAL
Cysteine
12
6
3 m%
2500 1250 625 312 156
Proportion of motile organisms 60 minutes after addition of -SH
>95 >95 >95 >95 0 >95 >95 84 0 0
>95 >95
92
00
79 77 41 0 0
73
50
40 0
0
20 20 6 0 0
12 15 4 0 0
0 0 000
DUP050314439
84 EAGLE
laboratory able to do some elementary analyses to arrive at the complete struc ture of BAL. However, it remained in the top secret category, and everyone nearby was unhappily aware of the fact that somebody in the place was working with mercaptides.
One difficulty with the possible syste mic use of BAL was its great lability, the fact that it not only easily oxidized but rearranged, and that it did not hold up either in water or in propylene gly col. We found, however, it could be stabilized by solution in peanut oil and benzo-benzoate, and that in glass sealed ampules such solutions could be auto claved with a minimal loss in activity. The ampules have now held up for something like five years, with no ap parent loss in activity, and no change in their iodine titration.
The fact that BAL acts by abstracting arsenic from the tissues was clearly shown by its effects on the urinary ex cretion of arsenic.
Fig. 2 illustrates an experiment in rabbits which had been poisoned by the injection of lewisiie, not locally applied to the skin but actually injected. As you see, when BAL was administered 24 hours after the original injection of lewisite, there was a striking effect on the rate at which the arsenic was ex creted in the urine.
You will note that this effect is tempo rary. The effect of a single injection of BAL is done and over with in two to four hours. For the first two hours, there is a striking effect on the excretion of arsenic. In the succeeding two hours the effect is less, and, thereafter, the rate of excretion falls to essentially normal levels. This suggested that, if BAL was going to be used therapeutically in man, these oil solutions of BAL would have to be injected approximately every four hours, in order to have a maintained, continuing effect.
Fig. 3 is an experiment with a differ ent arsenical. One sees the tremendous
TABLE I!
The Removal of Arsenic from Trypanosomes by' BAL and by Cysteine
(Trypanosoma) suspension = 1.9--3 x 10s per cc.)
Arsenical added
--SB compound added
Micrograms Compd. used per cc.
Phenyl arsenoxide
1.67
Time
Com-
after
pound arsenical
0 Cysteine
BAL
_
10'* 10'*
Final concen tration
--
0.01M 0.001 M
Condition of suspension 60' after addition of
--SB compound
% Motile
Ratio of arsenic concn. in trypanosomes
arsenic concn. in supernatant
0 154 43 33 81 9
p-Carbamido-
0 3' -- 0
phenyl
1.67
arsenoxide
BAL 3' 0.002M >95
257 28
0 5' -- 0
Mapharsen
1.3S
BAL 5' 0.0002M >95
118 15
*A.U organisms immobilized at time oi addition of --SH compound.
DUP050314440
BAL lim.', ------------------- ;-----------------------------------------------
85
effect on the urinary excretion of ar senic, when BAL was injected even 24 hours after the administration of die arsenical. The dotted curves in the lower left-hand are the rate of excretion in the control, untreated rabbits.
The next step was to attempt to apply these findings in man. Although there had been a great deal of study on the toxicity of BAL in experimental animals, those of you who have ever
tried to extrapolate toxicity data from mice, rabbits or dogs to man, are also aware of the fact that that extrapolation is fraught with danger. Usually one encounters in man toxic reactions which one does not see in animals, and often at dosage levels which in animals have no demonstrable effect.
Two experiments were started, one in some prisoners who volunteered for the study, and the other in a group of peo ple who came to the Rapid Treatment Center for anti-syphilitic treatment.
Although the lethal dose in animals, on a single injection was something like 40 mg. per kilogram, we began with % mg. per kilogram; and I am very glad we did. As long as the dosage levels were less than 2% mg. per kilo, per injection, there was no difficulty. As soon as the dosage exceeded 214 mg. per kilo, there were rather frightening reactions, the severity of which was pro portional to dosage.
There was lacrimation, a sense of burning in the mucous membranes, gen eralized aches and pains. But more dis turbing than any of these was a sense
Fig. 2--The effect of BAL (injected intramuscularly in peanut oil benzyl ben zoate solution) on the urinary excretion of Lewisite in rabbits. Lewisite was injected intravenously in propylene glycol solution (0.69 mg. per kg.). Twentyfour hours later the rabbit was given a single intramuscular injection of 10 mg. per kg. BAL (5 per cent solution in peanut oil with 10 per cent benzyl benzoate). Urine specimens were obtained by catheterization just before the
injection of BAL, and 4, 8 and 24 hours later.
Hours After Injection of Lewisite
Single intravenous injection (0.69 mg./kg - 0.0033 mmol./kg.)
DUP050314441
Fig. 3--The effect of BAL (injected intravenously in saline solution) on the urinary excretion of phenylarsenoxide in rabbits. A rabbit was injected intravenously with 0.56 mg. per kg. phenyl arsenoxide. Twenty-four, 48 and 72 hours later the rabbit was given an intravenous injection of 10 mg. per kg. BAL in saline solution. Urine specimens were collected by catheter ization just before and 4 hours after each BAL injection. The'open circles at the bottom of the figure refer to two control rabbits receiving no BAL- The striking effect of BAL on the hourly excretion of arsenic is indicated in the cross-hatched blocks at the top of the figure.
of anxiety, a sense of precordial com pression, and in a fair number of cases, at these upper dosages, a rather striking increase in blood pressure. All of these effects were temporary, and had largely disappeared within thirty minutes. Nev ertheless, we felt that we ought to recommend dosages not to exceed 2% to 3 mg. per kilo.
A considerable number of patients with arsenic poisoning were treated with BAL. Our first report included some 227 cases of various types of
arsenic poisoning, most of them occur ring as complications of antisyphilitic treatment in the pre-penicillin era.
Those included cases of arsenic der matitis, hemorrhagic encephalitis, blood dyscrasias, jaundice, mistaken admin istration of massive doses of arsenic, and the rather mild complication con sisting of fever and headache which is often, however, a premonitory symptom of beginning toxic encephalopathy.
The results were gratifying. In cases of dermatitis although there were a few
DU P050314442
I
BAL
87
which were refractory, and although the occasional case developed an abscess caused by a needle going through an infected area involved by the dermatitic process, the average hospitalization pe riod was reduced from the many weeks
and months with which you are all familiar to an average of something like 13 to 15 days. The symptomatic relief in 48 to 72 hours was sometimes quite dramatic.
In the cases of toxic encephalopathy,
Fig. 4--The effect of BAT. in cases with agranulocytosis. At the point marked zero in the abscissa, BAL was given.
DUP050314443
88 EAGLE
exactly as we found with trypanosomes and rabbits, the longer one waited be tween the onset of symptoms and the administration of the BAL, the worse the results. If BAL was not given for six, twelve or twenty-four hours after the beginning of evidence of cerebral damage, its therapeutic effects were rather minimal. If, on the other hand, BAL was given within six hours or less, after the beginning of symptoms of cerebral involvement, the results were quite gratifying. Our mortality in this group was something like 15 percent as compared with 50 to 75 percent in a control group.
In arsenical jaundice it did very little. There was an occasional case which re sponded dramatically, but most cases re sponded hot at all. This raises, again, the old question which you will find discussed at length in the standard hand books on syphilotherapy, as to the causa tion of so-called arsenical jaundice: whether it really is caused by the arsenic, or whether other factors may, perhaps, supervene.
In the blood dyscrasias, BAL did nothing in the cases which involved aplastic anemia, but was effective in cases of agranulocytosis.
Fig. 4 shows the effect of BAL in cases with agranulocytosis. At the point marked zero in the abscissa, BAL was given. The regular increase in the white cell count, after the administration of BAL and, in one or two cases, the very dramatic increase immediately after, strongly suggests that the return of the white count to normal in these oases of agranulocytosis was related to the fact that BAL had promoted the excretion of arsenic.
In the oases receiving massive doses
of mapharsen in error, we had several experiences. One case began pleasantly enough. The physician in charge of the clinic happened to be with me in Wash ington. His clinic was in the far west, and he received a telegram that, by mistake, the patient had received 1200 mg. of mapharsen. He wired back, "Give him BAL."
The patient was given two or three in jections of BAL and felt so much better that BAL was discontinued, whereupon the patient went on to develop acute atrophy of the liver in twelve days. Ob viously you cannot expect 1200 mg. of arsenic to be detoxified by two or three injections of BAL, amounting, in sum total, to 200 or 300 mg. of BAL, most of which is rapidly excreted.
As a result of our experience in these 227 oases it was recommended to the armed forces that, in cases of toxic re actions to arsenic, however encountered, if the reactions were severe, [e.g. a se vere dermatitis or toxic encephalopathy] treatment with BAL be given around the clock, every four hours, for at least two days, at A dosage of 2^ mg. per kilogram. In a man of 70 kilograms, this is 175 mg., or approximately 2 cc. of the 10 percent solution per injection.
At the end of those two days, if the patient was obviously better, the number of injections per day could be reduced from a total of six to something like two to four, and eventually discontinued completely after seven to ten days.
It was natural to attempt to extend these observations with arsenic to other heavy metals which, like arsenic, have , ability to react with sulfhydryl groups.
In experiments on antimony poison ing, for example. Fig. 5, it was shown that in rabbits which had been poisoned
DUP050314444
BAL
89
with a variety of antimonials BAL regu larly had the same striking effect on the urinary excretion of antimony as it had in arsenic poisoning.
The effects on survival, although not quite as dramatic, were nevertheless real. In animals which had received large amounts of arsenical, between 1 and 1.2 times the lethal dose and, in several instances, three or four times the lethal dose, we were able to protect, in some instances, 75, in others 91, and others only 50 percent of all the ani mals which had adequate treatment with BAL.
Our group did not study the effect of BAL in gold poisoning. Those of you who have been following the literature will, however, have seen case reports of patients with dermatitis resulting from the use of the gold salts in the treatment of arthritis. Although there is by no means unanimity of opinion, there is the consensus among those who have used the drug that it has definitely shortened the time of recovery.
In mercury poisoning. Dr. Longcope, Dr. Luetscher, and their associates have had what appear at the moment to have been extraordinarily favorable results with the use of BAL. I do not have to tell this group how difficult it is to evaluate results in mercury poisoning. Some patients who get minimal amounts die, and others who get classical amounts of mercury may recover. The definite evaluation of the effects of any thera peutic agent in mercury poisoning will require the slow and laborious accumu lation of data. There is, however, good reason to believe, on the basis of the data already in hand, BAL will prove highly effective in the treatment of mer cury poisoning.
A curious incident developed early in the application of BAL to the use in mercury poisoning. In normal subjects, as soon as one exceeds a dosage of 2 mg. per kilogram, one begins to run into toxic reactions. In these mercurypoisoned patients, however. Dr. Longcope and his associates found they could give 3, 4. and 5 mg. per kilo and have no trouble whatsoever. That was
Fig. 5--The effect of BAL on the urinary ex cretion of antimony. The experimental data, plotted on a percentage basis, refer to the twohour period immediately preceding the injec tion of BAL as 100. The symbols have the
same significance as in Fig. 1.
90 EAGLE
Fig. 6--The effect of BAL on the urinary excretion of lead, plotted on a logarithmic scale.
puzzling until it was realized that, in these patients who have taken large amounts of mercury, there is enough mercury in the body so that not only does the BAL detoxify the mercury, but the mercury also detoxifies the BAL. Otherwise toxic amounts of BAL com bine with enough mercury in vivo so as to reduce the immediate toxic reac tion to the BAL.
My ostensible l'eason for being here today is to talk about lead poisoning.
Dr. Germuth and I did some work with rabbits which was reported last year. I will say immediately that I feel as strongly as some of you that, to para phrase Gertrude Stein, a rabbit is a rab bit is a rabbit, and that it is dangerous and, indeed, impossible to extrapolate data from animals to man. The animal data can only suggest lines of attack, the ultimate answer to which is always the human trial.
With that necessary reservation, in
DU P050314446
BAL
91
Fig. 7--The effect of multiple injections of BAL on the urinary excretion of lead in animals with a subcutaneous deposit of lead acetate.
animals which were poisoned with lead acetate, by a method which has abso lutely no analogy to any type of lead poisoning one encounters in man, BAL had a striking effect in accelerating the urinary excretion of lead.
Animals Wkre given subcutaneous in jections of lead acetate in truly heroic doses. In these doses the lead is not absorbed but establishes a local depot
of lead, from which it is slowly ab sorbed, and the animal dies in the fol lowing weeks. It is thus a subacute type of lead poisoning.
In such animals, the injection of BAL does have a striking effect in promoting the mobilization and excretion of lead. I would like to point out that Fig. 6 is a logarithmic scale, so the differences are
even more pronounced than they appear to be at first glance.
In this chart the results have been ex pressed on a percentage basis. One hundred is the average excretion of lead in these animals immediately prior to the injection of the BAL. As you will see, for the first two hours after the in jection of the BAL in the animals, the
rate of excretion was increased from ten-
to fiftyfold. As has been regularly ob served, whether with arsenic or anti mony, and reflecting the pharmacology of BAL, the effect then fell off sharply in the following two hours, so that be tween the fourth and sixth hour the rate of excretion was only slightly greater than in the pre-BAL control
period.
DUP050314447
92 F.AGLE
I should say, also, that, although BAL the excretion of lead was so striking as,
did have this striking effect in promot perhaps, to justify its cautious thera
ing excretion, it did not promote the peutic trial in human cases."
survival of these animals.
That expresses my purpose in being
Fig. 7 shows the effect of repeated in here this morning. There are enough
jections of BAL. As one continues to data now with respect to the treatment
give BAL, what one gets back each time with BAL of cases of arsenic, gold,
progressively . diminishes. Apparently antimony and mercury poisoning, to
the first few injections of BAL permit suggest that, in those types of poison
the animal to excrete the lead which is ing, it has a definite therapeutic action.
readily mobilized, and has no effect on
The toxic reactions from the BAL
some of the massive depots from which have been minimal except for the occa
the lead can be mobilized only with sional and transitory local reaction at
difficulty. Just where those readily mo the site of the injection. 1 submit that
bilized depots may be, we do not know. it may, perhaps, be worth while to try
In these animals receiving massive BAL cautiously in the treatment of lead
amounts of lead acetate and, also, in poisoning with adequate controls with
animals which had been acutely poi respect to its effect on excretion, its
soned by the intravenous injection of effect on the blood concentration of lead,
lead acetate, BAL had no effect on sur on stippling, and so on. I would not be
vival. In one experiment which we have surprised if it were wholly ineffective,
not been able to duplicate, BAL actually but I think it deserves trial.
seemed to accelerate the death of the
I would like to submit for your con
lead-poisoned animals.
sideration, also, the possibility that a
In spite of that, I would like to read single injection of BAL, given once or
the last paragraph of our original paper. twice a week, to those of your men who
"It is clear that, under the conditions are most acutely exposed, might permit
of die present experiments, BAL had no the excretion of enough lead to put off,
demonstrable protective action and, at for a long time, the accumulation of
times, actually accelerated the toxic ef enough lead in the body to cause toxic
fects of lead acetate in rabbits. The data symptoms. "
offer no reason to believe that BAL
I wish to suggest, also, that, although
would prove of value in the treatment of BAL has proved so effective in the treat
lead poisoning in man.
ment of certain types of heavy metal
"Nevertheless, the experimental lead poisoning, there is no reason to believe
poisoning produced in rabbits by either that other compounds may not be de
the subcutaneous or intravenous injec veloped which are even more effective,
tion of lead acetate differs so materially and which, acting on the same principle i from that seen in man, both with respect as BAL may serve to abstract lead from
to the route of administration, the chem its combination with tissues.
ical form of lead, the chronicity of the
Ch a ir ma n Bo w d it c h : The discussion
intoxication and the organs which are of Dr. Eagle's paper will be opened by ! affected, that the results obtained with the professor of chemistry at Johns Hop
BAL in these experimental animals had kins University, who has led an exten-' .
no necessary significance with respect sive research project in deleading and,
to possible therapeutic activity in man. with his colleagues, has devised a new
"Despite the' present failure of BAL chemical substance for this purpose. Dr.
to detoxify lead in rabbits, its effect on Alsoph H. Corwin.
DUP050314448
BAL
93
DISCUSSION
Dr . Al s o p h H. Co r w in [Johns Hop kins University, Baltimore, Md.]: I think Dr. Eagle's cautious optimism in the case of BAL--or should I say conserva tive recommendations--are entirely jus tified. I, for one, would be most happy to see some clinical trials of the sort he suggests, carried out with BAL.
However, I want to direct attention to a slightly different matter in connec tion with these studies. Dr. Eagle's paper has emphasized the differences between various metals in their poisoning effects, and, particularly, in their resistance to antidotes.
This suggests that, in the elaboration of new antidotes, differences between the various metals must be emphasized so that the chemist can take advantage of the chemical differences in order to get effective agents for the treatment of poisoning.
If you read the paper of Peters, Stocke and Thompson, you obtain the concept that there will be a limited number of types of compounds which should be effective in the treatment of heavy metal poisoning. The reasoning seems tight; it seems hard to find a way through it to a new type of compound. But our examination of this subject has led us to believe that the reasoning is not quite
as tight as might seem on the first examination, and that there are ways through to the development of other compounds which may be more effective for certain metals.
One suggestion which came to us is the known affinity of dithizone for lead. Dithizone is used analytically in the determination of lead, and it will not combine with arsenic at all; neither will it combine with antimony. So, here we have a practical suggestion of a marked chemical difference between lead, in its reaction to a possible antidote, and arsenic, in its reaction to a possible antidote.
I want to suggest to you, briefly, how a chemist might go at the job of con structing an antidote for heavy metal poisoning. The accompanying photo graphs, which are cartoons, will give you an idea of what Dr. Eagle has pre sented in much more formal fashion for you.
Fig. 1--This suggests how a sulfhydryl enzyme may act in the body. I do not want you to interpret this too literally, naturally. I do not wish even to suggest that all sulfhydryl enzymes act similarly.
Here we have our sulfhydryl enzyme, with his two hands, and here we have a sugar molecule. You see he is nice
Figs. 1 & 2.
DUP050314449
94 DISCUSSION
Figs. 3, 4, 5 & 6 (from top to bottom).
and fat. The sulfhydryl enzyme reduces the sugar molecule and, in that, per forms a necessary metabolic function.
Fig. 2--The enzyme then has ex hausted its potentialities momentarily, and needs a helping hand from some thing else. It gets this from traveling glutathione in the blood or, perhaps, some other source of sulfhydryl which performs an exchange, reactivates the enzyme for further work, and is prop erly punished for putting its fingers into other people's business. [Laughter]
Fig. 3--This gives you a concept of how poisoning with a heavy metal-- in this case I have chosen mercury, mercury chloride--may work on the enzyme. Here is the enzyme ready to go to work on the sugar, but mercury comes along instead, and the enzyme is taken out of action, at least momentarily, by the mercury.
Fig. 4--BAL, as we have had pointed out, is effective in mercury poisoning. It takes the load off the enzyme which we thought originally was dead, but we have found now that, instead of being dead, the enzyme was only stunned and could be revived. You see the hydrogens are here, on the sulfhydryl compounds, ready to attack the sugar again, and the BAL carries off the load of mercury. Apparently it does not like it too much. [Laughter]
Fig. 5--This shows dithizone. As you know, it is a red dye. We thought it would be interesting to represent it by an Indian.
The chemical process of activation of these materials for metals probably involves polarization. It was our feeling that, if you could get materials which were strongly enough polarized, you would have at least one of the items necessary to bring about greater affinity of these substances for heavy metals.
DUP050314450
BAL 95
1
of tlie dithizone molecule. We obtained
a reasonably water-soluble compound
which had, to us, quite surprising
properties.
In the first place, I would like to em
phasize some of the disadvantages of
BAL. First is the odor that Dr. Eagle
has so graphically pointed out. The ma
terial can be smelled a mile away. Sec
ond, the relative toxicity. Approximate
ly 2% to 3 mg. per kilo can be given
without discomfort.
The substance we have worked with
has no odor at all. It substitutes for
odor, color. The animals and people
that have taken the substance turn up
1 one of llie properties of the substance with bright red urine. It is an orange to the exclusion of others. But, you see, red, so it is distinguishable from blood, in this process of activation, I have got but people are not always too careful
a negative sulfur here; this is a minus about this distinction.
. charge and there is a positive charge
This solubilized dithizone has been
down at the other hand. In this polari given parenterally at the rate of 400 mg.
zation process, the material is ready for per kilogram per day over a period of
attack on the heavy metal, so the ma four weeks, without any detectable signs
terial which can be polarized should be of intoxication.
most effective as an antidote.
In a "tour de force," we brought up
We feel that dithizone may have its a litter of mice that had never had any
advantages over BAL because the ma drinking water. Their water was always
terial has a more negative sulfur, a more contaminated with this material to the
vigorously attacking sulfur than BAL extent of 2,500^ mg. per kilogram per
does.
day. That is 2% gm. per kilo per day,
? Fig. 6--This shows you the inacti- throughout their lives. They never had
: vated enzyme, again, properly stunned, white water to drink. This red water
and the Indians go after the mercury. seemed to satisfy them perfectly well,
Fig. 7--This shows you they have, and they brought normal litters, and the
just like the BAL, taken their load off litters were brought up with red water
the enzyme and revived it for future instead of white water, and they had
activity.
normal litters. At that time we discon
That is enough fantasy in the matter. tinued the experiment, but we do not
I would like to report a few factual believe any .cumulative effects of this
results. Dithizone, itself, is too insoluble substance will probably be found. Two
to be effective in applications of this percent solutions are not irritating to
sort It is necessary, first, in order to the eye.
get an effective material, to make it
The disadvantages of the soluble di
water-soluble. This water solubility can thizone are first, its high cost. We did
be obtained in a number of ways chemi one rabbit experiment with the material.
cally. The way we chose was to put car All the rest of our work has been done
boxyl groups on in the desired positions with mice. The reason is that it took
DUP050314451
96 DISCUSSION
us about four months to accumulate the lead colic that.you see in people, and
enough substance to do the one rabbit severe intestinal involvement is certainly
experiment. This is something which present. So, we have both the kidneys
can be solved later, as Dr. Eagle has and the intestines to look after.
suggested to me privately. It might be
In animals that have been killed with
possible to get somebody to work this a lethal dose, you will find hemorrhages.
synthesis in large kettles instead of These can be entirely controlled with the
smaller pots of the sort we use in the soluble dithizone derivative, in a man
chemistry laboratory. But we have at ner which I suggest would he useful in
tacked the problem from another direc human cases, even when the colic has
tion. We have attempted to improve been properly controlled with calcium.
the synthesis and believe that the next We use colonic irrigations on animals
time we need more of the material, it that have had lethal doses of lead. We
will not be quite as difficult to procure. can bring them to autopsy then and find
It has another disadvantage, and that no hemorrhages. So, again, we have an
is its lack of stability to air. The pow effect of all or none.
der keeps quite well. The water solu
The antidote then is capable, when
tions must be stored under' nitrogen in brought into contact with the intestinal
order to have them keep, and we are not mucosa, of preventing intestinal dam
quite sure they keep perfectly under age. The kidney block, however, is much
these conditions, but they certainly keep more difficult.
longer under nitrogen than they do in
I want to say that, in the human cases
air. Hence, in our experimental work of lead poisoning, it seems to me quite
we always use freshly prepared solu probable that, even after the colic is
tions.
controlled and the pain has disappeared,
This substance was first developed there may be intoxication from lead
for cadmium poisoning; later for lead absorption, from the intestines, and
poisoning. It seems to work well against damage to the intestines. So, it seems
cadmium. There is no difficulty at all to me entirely warranted to try colonic
in converting a dose, which is 100 per irrigations with an antidote, as distinct
cent lethal, of cadmium to a dose which from colonic irrigations without an
has no lethal effects at all. It is a 100:0 antidote.
ratio. We can save all animals that are The kidney block is a much more dif
poisoned with a lethal dose of cadmium. ficult problem. Once an animal's kidney
However, the cadmium problem is es is blocked, it is hopeless, in our experi
sentially easier than the lead problem, ence, to try to revive it. Kidney block
because an animal that has a lethal dose takes place, sometime, fairly early in
of lead has many, many times the the stages of poisoning. We believe this
amount of metal in its body than the is one of the reasons why late antidote
animal that has the lethal.dose of cad use is not effective, while early antidote
mium. The result is that in lead poison ' use may be effective.
ing a tremendous volume of material
However, there are apparently two
must be moved.
kinds of kidney block. One, interference
Acute lethal lead poisoning is quite with the enzymatic work of the kidney
different from the type of lead poisoning which normally permits excretion to go
that was discussed yesterday. Acute forward. This is the normal type of
lethal lead poisoning has as one of its kidney block you get in heavy metal
manifestations kidney block. It also has poisonings of all kinds. The kidney
DUP050314452
BAL
97
ceases to function, but you do not nec essarily get a precipitate backing up be hind the excretory organ.
However, in these antidote treatments, you see another kind of kidney block. This is a mechanical kidney block due to the limited solubility of the metal antidote complex, and apparently it is not due to poisoning, although it is very difficult to be certain of this matter. But in the case of cadmium poisoning
we have been able to take certain steps which will help start kidney action again, and, on doing this, the block is removed and the kidney seemed to func tion quite normally. I believe that this is possible in the lead cases, too.
In the lead cases, the amount of ma terial that has to be handled by the kid ney, as I say, is approximately 50 times as great as it is in the cadmium cases, so that the possibility of mechanical blocking of the kidney is much greater.
We fmd that the administration of a large amount of physiological salt solu tion is the best method for unstopping the kidney; that is the best we have been able to find so far.
Under these conditions, the kidney is opened up, and a lot more of the heavy metal is eliminated. I do not feel that we yet have the answer in lead poison ing. I think that a certain amount of optimism is in order. I think, perhaps, we are on the right track.
We are able with this antidote, and in the case of mice only --- I must under line again -- we are able to increase the survival time of all animals. We are not able to save all animals. We hope that by improved techniques of administra tion we may be able to save all animals from lethal doses of lead. We certainly feel that we have here a substance which warrants further investigation in the control of colic, in the speeding up of recovery from metal poisoning, and per haps even in the treatment of acute
lethal lead poisoning which occasionally
occurs.
Ch a ir ma n Bo w d it c h : This subject is
now open for brief discussion.
Dr . Go r d o n C. Ha r r o l d [Detroit,
Mich. ]: I would like to ask whether or
not it would be possible to take this
insoluble compound and add some ma
terials that would gradually release this
very insoluble material, so you could
slowly eliminate that block.
Dr . Co r w in : All I could say to that
is that we have tried but have not been
successful. Apparently what happens is
that this material, like BAL, mobilizes
the lead, and, once you get the block
formed, more and more of the substance
pours into the kidney. The thing you
have to do is to keep the block from
forming, or else remove it in the early
stages by flooding the kidneys. We have
not been able to do anything besides
flood the kidneys to get the block to
move.
Dr . D. J. La u e r [Kettering Labora
tory, University of Cincinnati, Cincin
nati, Ohio]: I enjoyed very much the
interesting, lucid discussion this morn
ing on BAL by both Dr. Eagle and Dr.
Corwin.
-
I would briefly like to present some
observations made by Dr. Henry Ryder
and others of the stall of the Kettering
Laboratory, relating to the use of BAL
in cases of human lead poisoning, a
preliminary report of which was pub
lished in Science, July 18, 1947, by
Ryder, Cholak and Kehoe. Two groups
of patients, all ill with acute lead poison
ing, were studied.
There was no evidence that the two
groups of men were from populations
with different attributes. The type, dura
tion, intensity and multiplicity of symp
toms were similar in the two groups.
There were 11 in one group and 16 in
the control group. These people were
all hospitalized.
98 DISCUSSION
Treatment with dithiopropanol was
individualized, and usually given in each
phase to the limit of tolerance. The
first patient was given 5 mg. per kilo
immediately, and 2% mg. per kilo every
four hours, for eleven doses. -Therapy
was discontinued because of hyperten
sion, severe joint and muscle pains, or
subsidence of colic.
In later cases it was attempted to give
more dithiopropanol by less frequent
injections over a longer period of time.
This was unsuccessful.
The average patient was treated three
days and given I.7gm. of dithiopropanol.
Some patients appeared to be better and
some worse, following the administra
tion of BAL. It seemed apparent that
the drug had no immediate spasmolytic
effect.
The time at which colic or pain re
mained persistently absent appeared not
to be influenced by the administration
of BAL. Persistent weakness was present,
uniformly, after the disappearance of
pain.
.
Men treated with dithiopropanol did
not recover and return to work more
promptly than did those untreated.
From the clinical viewpoint, then, the
use of BAL was without beneficial
effects.
There was, however, a characteristic
and dramatic effect upon the lead metab
olism. The lead concentration in the
urine increased from five- to fifty-fold
with the greatest relative increase in the
men that had not been exposed ab
normally to lead. The effect on the
blood lead concentration was immediate
and in the reverse direction from that of
the urine. By seven and one-half minutes
the blood lead concentration was falling
rapidly and it continued to fall, but
with diminishing rapidity, the maximum
fall being reached between one and
eight hours. Gradually there was a
return in the lead concentrations in both
blood and urine to levels approximating those observed before the administration of BAL.
The plasma and fecal lead concentra tions were unchanged by the therapy. The total amount of lead eliminated from the body by a single injection did not exceed 1 mg. and was usually a few tenths of a milligram.
In summary, it has been observed that dithiopropanol causes a prompt drop in erythrocyte lead concentration and an immediate rise in the urine lead concentration to a degree far greater than that observed following any other type of therapy tested.
It has also been observed that the drug has no spasmolytic effect and does not shorten the course of the spontane ously reversible condition, lead colic.
It is, therefore, inferred that the me chanism of intoxication and the mecha nism of storage and elimination of lead are not intimately related.
The observed effects on lead metabo lism are consistent with the hypothesis that lead combines with some erythro cyte component and that this combina tion can be partially reversed in vivo by BAL therapy, but the failure of symp tomatic response to therapy gives no support to the theory that an enzyme system dependent on thiol groups for its activity is involved in the mechanism of lead poisoning.
The data of these studies will be pub lished by these men in detail soon.
I am now interested, under the stim ulus of Dr. Eagle, in using BAL prophylactically. About three weeks ago I took two men of the same age, the same race and the same length of exposure, doing identically the same job, on a- reverbera tory furnace. One works from midnight to eight in the morning, and the other takes over from eight in the morning until four in the afternoon.
Their urinary and blood lead levels
DUP05031 4454
BAL
99
are about the same; their stipple count Union, Inc., Milwaukee, Wis.]: I wish about the same; and their state of health to ask Dr. Eagle a couple of questions.
about the same.
There have been noted in the literature
I ran a control period on them for some side effects, with the use of BAL
about a week. Then, one I gave 2 mg. notably that it inactivates insulin or the
per kilo of BAL, and the other one I production of insulin, perhaps, and the
gave an equivalent volume of liver ex action of insulin as an enzyme. If so,
tract. These data have? not been avail would there be any permanent effect able for study and, therefore, they may on that mechanism? Also, does Dr.
not be introduced into the record at this Eagle see any reason why procaine
tune. Thank you for this opportunity.
should not be combined with the BAL, because it is an extremely painful pro
Ch a ir ma n Bo w d it c h : We are ap cedure to have that given, as I have
parently faced with a new unit of mea observed, and I wonder too, if the use
surement. Did I understand Dr. Lauer of procaine would either decrease the
to refer to 2 mg. per "Kehoe?" [Laugh effectiveness of the BAL or otherwise
ter ] - make it dangerous to use?
Is there any further discussion of this
Then I would like to know- what he
very interesting subject?
thinks of the fact that has been noted
Dr . Wil l ia m C. Wil e n t z [National in the literature that the BAL and cad
Lead Co., Perth Amboy, N. J.]: This mium end-product is toxic to the kidney
is the first time I have ever heard this tissue.
discussion on BAL. So, it strikes me as
Ch a ir ma n Bo w d it c h : Will you re
a most interesting thing.
spond, Dr. Eagle?
I would like Lo tell Dr. Eagle some
Dr . Ea g l e : I would like to make it
thing along this line; I noticed, in the clear that I am not here to recommend
treatment of these animals, you injected anything, and that I am not a proponent
them when they were acutely poisoned. of any particular method of treatment.
You know, in lead poisoning, most men
The only point I am trying to make
do not approve of such dramatic things, is that, in support of Dr. Corwin, it
even the men who advocate deleading. seems to me that the last word has cer
They wait until the acute phase is over. tainly not been said on the treatment
So, there is some difference.
of lead poisoning.
I am curious to see what is going to
Everything we have observed in other
happen in the long run. In other words, types of poisoning indicates that the
should these men, in trying their experi earlier treatment with BAL is begun,
ments on the human, employ BAL dur the better. If it were to be effective, one
ing the acute stage of human lead poi might suppose it would be most effective
soning? Where are they going to be if in the acute stages. On the other hand,
they do not give it during the acute there is very little in the animal data to
stage? In other words, will it be safe indicate that BAL is going to be dra
lo give BAL during acute stage or in matically effective in the treatment of
chronic stage as a deleading agent? I lead poisoning. I think that studies
would welcome some advice along these such as those of Dr. Lauer ought to be
lines so we could help establish the carried on, perhaps on an even larger
value of BAL in the human lead intoxi scale, in order to establish once and for
cation cases.
all what BAL can or cannot do in the
Dr . El s t o n L. Be l k n a p [Globe- treatment of lead poisoning.
DUP050314455
100 DISCUSSION
The other aspect of the problem is, have developed in the many hundreds
will BAL have any effect in the preven of patients who have been treated with
tion of lead poisoning? Can one, by BAL for various types of arsenic poi
pulling out a fraction of a milligram of soning.
lead once or twice a week from whatever
As to cadmium poisoning, there is
focus it can be mobilized, effectively some evidence that, although BAL ef
delay the onset of symptoms in a large fectively mobilizes cadmium, that mo
number of men? 6 Dr. Lauer's attempt bilized cadmium is toxic to the kidney.
with these two men is laudable. I think
So far at least, we have seen no evi
it ought to be increased tenfold and a dence in man of this possible toxic ef
hundredfold, to get data of statistical fect of BAL in cases of lead poisoning.
significance.
Nevertheless, I again would suggest
But the last and most important point caution in its use. There was a case of
is the report of Dr. Corwin. There are, lead poisoning treated by Dr. Robert
I think, enough data in hand to indicate Austrian in the Johns Hopkins Hospital
that one can develop compounds with while I was there. In this case, as Dr.
specific affinities for heavy metals, and Ryder and his associates did in their
with relatively minor toxicities for the series, we observed a striking effect on
host. I think it is in the development lead excretion. The man recovered un
of such compounds, almost certainly not eventfully; but he may have recovered
BAL, hut compounds which, like BAL, anyway. It will take just the type of
have a specific affinity for heavy metal study Dr. Lauer has undertaken in the
and relatively minor affinity for the host two cases he described, on a much
tissues -- it is in the development of larger scale, to evaluate BAL or any
such compounds that we have the best other agent suggested for the treatment
hope for the successful treatment of of lead poisoning.
lead poisoning.
Dr . Be l k n a p : If the doses as reported
As to the question concerning the by Dr. Lauer were a shade too heavy,
local reaction to BAL, in preliminary that might have accounted for some of
trials I think the men should be fore the symptoms.
j!
i
warned that the injection is going to
Dr . Ea g l e: Yes, I think they were.
hurt somewhat and they may have local They exceeded anything we have dared
pain for fifteen minutes or half an hour to use even in our treatment of severe
after the injection. In my experience arsenic poisoning. In mercury poison
at least, they do not mind it. The incor- ing, there is a mutual detoxification. If
poralion of 20 percent benzylbenzoate one is going to try this in lead cases,
in the peanut oil solution has done a I would recommend injections of the 10
great deal to cut down the local reac percent solution at a dosage of 2.5
tion. I cannot believe that procaine mg. per kilogram at four-hour intervals,
would have any chemical effect or repeated four times a day. This brings
pharmacological effect on the activity of the treatment within the compass of a
the BAL, and it perhaps could be tried. twelve-hour day. I would suggest no
Although it is true that BAL added more than that in treatment, continued
directly to insulin does have an effect, for two to four days, and then slope off
we have seen no significant effect on to about two a day.
blood sugar in the patients which have
If any of those present are going to
been studied from that point of view. try BAL for the prevention of lead poi
If it. had had an effect, I think it would soning, and if you can get the coopera-
DUP050314456
BAL
101
m--------------------------- --
tion of your men [and that is difficult]
`I would suggest one or two injections a
week, again at a dosage of 2x/z mg, per kilogram. In a man weighing 75 kilos (165 pounds) this represents 1.9 cc. of the 10 percent solution.
Ch a ir ma n Bo w d it c h : Our next paper will be by a man who was associated with the University of Illinois in fuel utilization for the Geological Survey prior to the war. During the war he
was head of the Coal Division of the Bureau of Mines, and, in that connec tion, became interested in our present subject while in the Ruhr. He is now director of the Air Pollution Control District of Los Angeles County, Cali fornia.
Dr. Louis C. McCabe will speak on "Air Pollution Control Regulations in Los Angeles County."
REFERENCES
The Systemic Treatment of Arsenic Poi soning with BAL (2, 3-Dimercaptopropanol). Yen. Dis Inj. 27: 114, May 1946. Harry Eagle.
Clinical Uses of 2, 3-Dimercaptopropanol (BAL). I. The Systemic Treatment of Experimental Arsenic Poisoning (Mapharsen, Lewisite, Phenylarsenoxide) with BAL. J. of Clin. Inv. XXV: 451-466, July 1946. Harry Eagle, Harold J. Magnuson and Ralph Fleischman.
The Protective Action of BAL in Experi mental Antimony Poisoning. J. Pharmacol, and Exp. Therap., 89: 196-204, Feb. 1947. Harry Eagle, Frederick G. Germuth, Jr., Harold J. Magnuson, and Ralph Fleischman.
The Effect of BAL on the Excretion of Arsenic in Arsenical Intoxication. /. Clin. tnv. XXV: 534-40, July 1946. J. A. Luetseher, Jr., Harry Eagle, and W. T. Longcope.
The Systemic Treatment of 227 Cases of Arsenic Poisoning (Encephalitis, Dermatitis, Blood Dyscrasias, Jaundice, Fever) with 2, 3Dimercaptopropanol (BAL). Am. J. Sjrph., Gonor., and Yen. Dis. 30: 420-441, Sept. 1946, Harry Eagle and Harold J. Magnuson.
The Efficacy of BAL (2, 3-Dimercaptopro panol) in the Treatment of Experimental Lead Poisoning in Rabbits. J. Pharmacol, and Exp. Therap. 92: 397410, April 1948. Frederick G. Germuth, Jr,, Harry Eagle and with the technical assistance of Jean C. Grossberg.
DUP050314457
AIR POLLUTION REGULATIONS IN LOS ANGELES COUNTY
By LOUIS C. McCABE, Ph.D.
Director, Los Angeles County Air Pollution, Control District, Los Angeles, Calif.
Los Angeles has experienced an in creasing nuisance from atmospheric con tamination by fumes, gases and dusts in recent years. The term "smog" has been applied to this complex of atmos pheric contamination which frequently limits visibility to a few blocks and causes eye, nose, and throat irritation. It attained objectionable proportions in the early years of the war, and, in response to public demand, the 1947 session of the California legislature added comprehensive statutes to the Health and Safety Code, namely Chap ter 2, Division 20, for the purpose of controlling it. The Act recognizes that the problem is broader than "smoke abatement" and provides that the Board of Supervisors of any county on finding that serious "air pollution" exists, may establish a county-wide district to con trol it and may pass such supplementary regulations as are required.
Topography and meteorological con ditions aggravate the effects of air pollu tion1 in the Los Angeles Basin. High mountain ranges surround it on three sides. Prevailing winds during most of the year are westerly or southwesterly during the daytime while their average velocity is only slightly more than six miles per hour on a 24-hour basis. These on-shore "sea breezes" move gently over the area from 8:30 in the morning until midnight During the night a light land breeze develops which moves down the mountain valleys toward the sea-coast at an average of about one mile per hour. In the sum mer and early fall, temperature inver sion limits the vertical distribution of the atmospheric pollution as the local winds move it over the area from the west during the day. If pollution does
not escape through the mountain passes during the day, it returns on the night breeze to be reinforced by the next day's contamination. The inversion layer is very resistant to turbulence and holds the pollution near the ground. Visibility is greatly restricted at times of low inversion.
In Los Angeles County, essentially no coal is burned and air pollution from improper oil firing is comparatively rare. The great majority of the air pol lution problems that are encountered stem from emissions that are a func tional part of the plant operation, and careful operation and design cannot al ways prevent these emissions. Frequent ly, the only way they can be prevented is by the addition to the plant of me chanical equipment designed to remove the emissions. Most of the dusts and mists we would control are less than one micron (1/25,000 in.) in size. This is largely a new and untried field of con trol in this area. Dust particles larger than ten microns are relatively easy to remove from effluent gases2. It is these particles that deposit under normal meteorological conditions within five or ten miles of their origin and are prob ably responsible for most of the dust precipitated over the city. Improved cyclones may be used with the expendi ture of a large amount of power to re cover dust down to five microns in diameter. Between one and five microns, various types of water scrubbers can be used. Below one micron, the dust parti cles are most effective in scattering light and, therefore, are responsible for low visibility. These particles do not settle but remain suspended unless they are washed out by rain. They are effectively removed at the point of origin by the
102
DUP050314458
AIR POLLUTION
103
electrostatic precipitator, fine fiber, or thick sand filters or the Venturi scrub ber.
The rules and regulations of the Dis trict which affect the metallurgical in dustries are briefly summarized as follows:
1. RINGELMANN CHART. A person shall not discharge into the atmos phere from any single source of emission any air contaminant for a period or periods aggregating more than three minutes in any one hour, which is
(a) As dark or darker in shade as that designated as No. 2 on the Ringelmann chart, as published by the United States Bureau of Mines, or
(b) Of such opacity as to obscure an observer's view to a degree equal to or greater than does smoke described in subsection (a) of this rule.
2. PARTICULATE MATTER. A per son shall not discharge into the at mosphere any dust, ashes, charred paper, soot, grime, carbon, or other particulate matter exceeding 0.40 grains per cubic foot at the point of discharge into the atmosphere.
3. SPECIFIC CONTAMINANTS. A person shall not discharge into the atmosphere any one or more of the following contaminants, in any state, or any combination thereof exceed ing in concentration at the point of discharge: Lead......................... 0.035 grains per cubic foot Zinc oxide............... 0.035 grains per cubic foot Sulfur compounds . 0.2 percent by volume (calculated as SOr)
Fourteen industrial groups have com pleted or are in the process of studying their specific air pollution problems. This paper is concerned primarily with
the investigations and findings of the non-ferrous founders, the gray iron founders, and the two open hearth steel plants of the area. The writer has drawn heavily on reports on the nature and quantity of contaminants furnished the District by these three groups.
The non-ferrous founders employed six consulting engineering organizations or laboratories in Los Angeles to make a series of 16 tests on six representative types of equipment in use by the nonferrous founders for eight different al loys. The factors evaluated in the survey were: (a) Type of furnace. (b) Maximum and average concentra
tions, and the variation of concen tration during the melting cycle, of both fume and other particulate matter.
(c) Type of fuel used,-- oil, gas or electricity -- and fuel-air ratios.
(d) Composition of the alloy. The investigators found it necessary
to establish a procedure for field sam pling and laboratory analysis. The sur vey of representative foundries showed that in many cases the products of com bustion and the material volatilized from the furnaces are discharged directly into the air without any specific exhaust sys tem. In some cases, hoods and exhaust stacks were already installed but in gen eral they depend on gravity circulation for exhausting the system. The temper ature of the gases discharged from the furnaces range between 2,500 and 3,500 degrees Fahrenheit, and are diluted by a considerable amount of secondary air on entering the stack. Direct sampling of gases was not feasible at the furnace temperatures obtaining, and where ex haust systems were not already pro vided, a portable hood, stack and blower was used for measurement of air flow and for obtaining samples for analysis (Fig. 1).
DUP050314459
104 McCABE
The following conclusions for general operating conditions and procedures are drawn from Table I. The average loss due to volatilization and recondensation for average brass foundries and smelting operations is approximately constant-- in the neighborhood of one percent of the total melt charged. A loss of this magnitude for these operations will re sult in violation of our present regula tions. Foundries handling copper-lead, magnesium, aluminum, and high nickelbrass alloys, however, will be within the legal limits of emissions, providing good foundry practices are followed in all operations.
It is estimated that in addition to the cost of hoods and stacks, the installation of equipment for removal of fumes from the stack gases will cost between $2,000 and $20,000 per furnace exclusive of operating and maintenance cost.
The average particle size of zinc fume
is less than one-half micron. In high concentrations, the fume may agglom erate into large particles, but at other times the particles remain discrete. The small particle size precludes the use of cyclones. The non-ferrous foundry re port summarizes three general types which may be applied to their installa tions at. reasonable expense: 1. Fabric filters (bag houses) are prob
ably the most efficient of the three types and, where cooling flues are required, will probably be the high est in first cost of installation. Bag houses may be either automatic or manually operated. 2. Mechanical scrubbers are available in a wide range of sizes and types with auxiliary equipment of many different kinds to meet special con ditions. Generally speaking, the me chanical scrubber would not be as efficient as the bag house on foundry
Fig. 1--Diagramatic sketch of sampling layout for typical brass furnace.
DUP050314460
AIR POLLUTION
105
TABLE I
Significant Data for Loss Calculations Non-Ferrous Industry
Type
Stack Loading Average at 6G*F. Wt. of Melt
Total Loss
Time of Melt
Effluent Melt Disch urge Ratio at 60F.
Yellow Brass Medium Melt Ave. of 2 tests
Red Brass Medium Melt Ave. of 2 tests
Red Brass Heavy Melt Ave. of 2 tests
Brass Smelting 1 test
0.42$ gr./cu. ft. 0.2S2 gr./cu. ft. 0,409 gr./cu. ft. 0.39 gr,/cu, ft.
800 lb.
1.31 %-- 10.47 lb. 90--100 min.
00 lb.
3.0l%-- 6.00 1b.
78 min.
3650 lb.
0.985%-- 36.0 lb.
25 tons 1.26 %--629.0 lb.
161 min. 25 hr.
99% ZnO
215 cu. ft./lb.
90% Zu
282 cu. ft./lb.
169 cu. ft./lb. 226 cu. ft./lb.
Copper-lead, magnesium, aluminum, and bigh nickel-braes alloys will give low discharges and Total losses of less than 0.2% (.002).
emissions. The overall cost, for equivalent volumes would generally be lower than for a bag house.
3. Packed tower. This type of collec tion equipment is generally adapted to handling large volumes of gas, carrying relatively low concentra tions of solids. Their efficiency is generally lower. The first cost of the installation for equivalent vol umes, is usually lower than fabric filters. This type of equipment is
generally used for fine dust in rela tively low concentrations, and the successful application of packed towers to foundry gases will depend upon the effectiveness of "wetting agents."
Three pilot installations are now un dergoing test by the Non-ferrous Found ers Association for the purpose of de termining recoveries and operating costs. The results of these pilot opera tions will enable each operator to de-
TABLE II
Significant Data for Loss Calculations Ferrous Industry
Type
Stuck Loading
Wt. of Melt
Total Loss
Time of Melt
Effluent to Melt Ratio
Discharge
Gray Iron Light Melt
Medium Melt 1 test
1.604 gr./cu. ft. 1.1 gr./cu. ft.
Heavy Melt 1 test
0.798 gr./mt. ft.
Steel
Open Hearth
2 tests
0.79--0.86 gr./cu. ft.
6.17 tons 0.743%-- 92.1 lb.
80 min. 32.5 cu. ft./lb.
17.0 tons 1.45 %--S08 lb.
156 min.
91.5 cu. ft./lb. Lead and ZnO 5% each
Silicon Oxide 30% Iron Oxide 10%
Remainder carbon aceous material
50.4 tons 0.564%--570 3b. 5 hr. 20 min, 49.5 cu. ft./lb.
7 to 5 ton9/hr.
0.63 to 0.65
8% to 10% hr.
726 to 667 lb.
55.6 to 53.1 Oxides of zinc, cu. ft./lb. lead, iron and
silicon
Mean particle size. 0.25 microns No particle above 3 microns
Opacity in excess of 40% during majority of melt
DUP050314461
10d McCABE
Sample
A B C D E F G
TABLE III
,
Summary of Concentrations in Samples Collected
(Grains per cubic foot at 60 F. and 14.7 psii
Time P. M.
2:51-5:02 5,2:51 - 4:21 4:26-5:02 5:46-9:30 5:46-6:46
7:09-8.09 8:30-9:30
Particulate Matter
1.421 1.962
--
0.420 1.104 0.441 0.368
- Zinc Oxide
--
1.--344
--
0.482 0.153 0.103
Lead
____
0.138
____
--
0.095 0.048 0.046
cide which type of equipment will meet his individual requirements. The Asso ciation's consultants estimate that the installation cost in collection equipment will range from $.25 up to $1.50 per cubic foot of gas handled, depending on the character of emission, the efficiency required, and the preference of the operator. The cost of the hood and duct systems is estimated to be from $.20 to $.50 or more per cubic foot of gas
handled. The methods and procedures used by
the ferrous industry for obtaining the data given in Table II is essentially the same as that previously described for the non-ferrous industry. The ratio of percent loss to total weight of the melt establishes that the effluent-melt ratio in cubic feet per pound is a measure of efficiency of foundry practice. On the basis of this ratio and from the study of the tabulations in Table II for the ferrous industry, it was found that the percent loss amounted to between 0.5 percent and 0.9 percent. One test showed a loss of 1.59 percent but a further study of the effluent-melt ratio shows that this high loss results from excessive dilution. During the major portion of the melt time, the ferrous industry violates the present law both as
to stack loading and opacity. The total particulate matter, zinc
oxide and lead concentrations for an open hearth furnace are shown in Table III.
Particle size of emissions was deter mined from filtration Samples A and D, taken during the period between charges and the melting period follow ing the second charge, respectively. In addition, 14 separate samples were taken directly on electron microscope screens by means of a thermal precipi tator in order to obtain more accurate results on the smallest particle sizes.
Particle size distribution is summa rized as follows:
St'ze Sample A
1-3 microns
10.5%
0.5-1 "
30.2%
0.15-0.5 "
49.0%.
Below 0.15 microns 10.3%
100.0%
Sample j 4.1%
26.6% 49.9% 19.4%
100.0%
Regulations relative to certain specific < dusts and particulate matter have been expressed in grains per cubic foot at 60 degree Fahrenheit and 14.7 psi pres sure. This approach encounters certain difficulties unless a standard quantity of excess air is established as well. It is anticipated 'that future regulations will
DU P050314462
AIR POLLUTION
107
be on a mass-rate basis. In order to ob tain effective improvement in visibility and to bring about a reduction of sub micron material, it may be necessary to specifically limit it.
BIBLIOGRAPHY
' Beer, Charles G. P. and Leopold, Luna B., "Meteorological Factors Influencing Air Pol lution in the Los Angeles Area." Trans., American Geophysical Union, Vol. 28, No. 2, (April 1947).
1 Johnstone, H. F.. University of Illinois, Urbana, Illinois, Personal communication.
Ch a ir ma n Bo w d it c h ; The leader of the discussion of Dr. McCabe's presen tation was formerly associated with Pro fessor Philip Drinker at Harvard, after which he was with Dr. Carey McCord in the Bureau of Industrial Hygiene at Detroit, and from 1941 to 1946 was director of that Bureau. He has been on the faculties of Wayne University and the University of Michigan and is now ventilation consultant to the Gen eral Motors Corporation in Detroit. Mr. William N. Witheridge.
DISCUSSION
Mr . Wil l ia m N. Wit h e r id g e [Gen eral Motors Corp., Research Labora tories Division, Detroit, Mich.]: My function here is going to be actually and literally as a leader because there are at least a dozen of you here whose work should be in the record in prefer ence to mine. As a matter of fact, I suspect, because of the lateness of the hour, we may not give everyone a chance to make the comments that they would like to make, because I am sure there are many who have rather strong feelings on certain phases of the subject.
It should be clear, I think, that the problem in Los Angeles is greatly dif ferent from that of accidental incidents such as occurred at Donora and those which have appeared in the history of air pollution.
The problem of community pollution that is continuous and prolonged and develops a response such as has occurred in Los Angeles indicates definite need for a very good program of control and, of course, an excellent program of study of the scope of the problem and the possible methods of control.
I think Dr. McCabe has, perhaps, the supreme outdoor air pollution labora tory in the world.
It was stated yesterday by someone that much has been written on lead poisoning and a great amount has been nonsense. So far as I am concerned, there has been the greatest amount of nonsense published and spoken about the subject of atmospheric pollution, and I do not refer to the specific case of Los Angeles. Every time a single incident occurs, a great deal of excite ment develops, way out of proportion to the real nature of the problem. Al though that no doubt hastens the inves tigative process, against this must be charged the community-wide injurious effects of mass hysteria and, perhaps, widespread incidence of so-called "com munity hypertension."
So far as my own opinions on some of these matters are concerned, I think it would be well to delay them and to get into the record some of the com ments of men who have specialized in this field and who have done some very interesting and important work in their own communities.
I would like, first, to suggest that we hear from Mr. Dyktor, who is now Com missioner of Air Pollution Control for the City of Cleveland. It is quite a temptation for me to describe, briefly.
i#
_ ..
DU P050314463
108 DISCUSSION
die nature of his program because I feel, in an administrative way, that it is a rather ideal combination, but I think Mr. Dyktor should do that himself, and I would like to hear from him now.
Mr . H. G. Dy k t o r [Commissioner of Air Pollution Control, Cleveland, Ohio]: Mr. Chairman, I have certainly been taken by surprise. I settled myself down to listen to Mr. Witheridge review the paper given by Dr. McCabe. I did not expect to come here and expound my views on it. Some of you have heard them before, so I shall bore you again.
In so far as Cleveland is concerned, we are quite conservative. We make haste very slowly, and I must admit that we do that under the compulsion of ignorance, because we realize that there is so much to find out in connection with the air pollution, and we have not yet scratched the surface.
Therefore, it behooved us to move, as I said before, very slowly. The first step was to pacify the public that made the demand for the better life and expected miracles to happen overnight, just because legislation was. passed through council, and, on the other hand, to pacify industry which expected, as a result of this piece of legislation, that they would be dealt with harshly because they are, naturally, the source of emis sion of the pollution.
So, the job is quite educational and informative, so far as I am concerned. The pacification of the public, at times, is quite possible, if you attend the socalled mass meetings where people use you as a target for their complaints and, if you have a thick skin, you can take it. You will find, however, that it generally develops afterwards that they did not mean to be harsh with you, that they understand what the problem is, and will go along with you.
With industries, of course, I had an advantage. Because I had been in charge
of industrial hygiene before I took on the job as Commissioner of Air Pollu tion Control, they knew me personally, they knew that I would cooperate with them and that I would not do anything drastic, in so far as they were concerned.
Not knowing very much about air pollution control, because of the lack of fundamental information--and I admit that quite frankly--we have adopted the attitude in Cleveland that the various in dustries should be responsible for clean ing their own houses. We always went on the premise that they knew their own business far better than we did, and, if they needed help, they knew where to get it, and we were ready to furnish it to them. That was quite accepted, and, be lieve it or not, the industries in Cleve land, at least, under this process of cooperation and education, have already spent hundreds of thousands of dollars in the matter of just fifteen months. As a matter of fact, we have their confi dence, and they are calling us in almost daily in order to help them out with their air pollution problems.
I find that very fine because I am free to judge by results rather than by arbi trary limits. I would not know at pres ent what limits to set, even from the point of view of industrial toxicology, where we do have many, many yard sticks, of which some are good and some are not so good, as you know. When you get down to industrial nuisances, with their exceedingly low concentra tions, we really do not know because what may be a nuisance to one person may not be a nuisance to another. Hu mans vary that much, as you all know. Therefore, we are very cautious in es tablishing maximum allowable concen trations for nuisances.
We have quite a variety of industries in Cleveland. We have three very large steel plants; we have dozens of found ries. We have the lead industries. We
DU P050314464
AIR POLLUTION
109
have chemical industries, and others and, when 1 say "smoke abatement" I
jJMt 7
covering the entire gamut. I would be mean smoke that is the result of incom
jf in a very poor situation if I produced plete combustion of fuels. Also we have,
a set of maximum allowable concentra of course, what I consider, for the size
tions for nuisances and made industries of Cleveland and for the activity, a
' live up to them, without knowing before pretty good laboratory. It took me quite
hand that they could do so.
a long time to sell the idea both to the
We have not promised the people city council and to the budget director,
elimination of air pollution, not at all. in order to get the necessary funds for
We have only promised them that it it.
would be reduced to a level where indus
Today we have excellent team work
try and the community will be able to within the division, because we have
live at least peacefully, if not quite com many staff meetings whereby I straight
fortably, side by side.
en out quite a few of these problems of
I think, if we do that, we shall have personality, which you find among pro
' accomplished a great deal, and, after fessional people. I am also able to take
wards, it will he a job of keeping the sole responsibility for the conditions in
, pollution at that tolerable level.
Cleveland, give service to the commun
As far as our administration of this ity and to industry, and keep every
problem is concerned, and of which Mr. thing under control, as far as I can.
. Witheridge gave you an inkling, it came
I do not mean to imply that we have
about because of the fact that some of succeeded. We know that we have
f these activities were handled in different passed the apex of the curve. We are
departments. Those of you who have on the downgrade but a little, but we
had government experience know that are moving in the right direction.
it is very' easy to pass the responsibility Thank you very much.
from one to another, and thereby duck
Mr . Wit h e r id g e : Thanks very much,
the issue and let the other fellow carry Mr. Dyktor.
the burden. But that did not produce
I was very glad to hear, during Dr.
1 results.
McCabe's discussion, the mention of his
Because of this lack of results there feeling that the standards for stack
was a Citizens Air Purification Com "loading" or discharge into the atmos
mittee appointed by the Mayor. I did phere probably in the future will be
not much care for the word "purifica based on the mass of material released
tion" but that was none of my doing. rather than specific concentration.
This committee prevailed upon the city Those of you who have copies of the
fathers to do something about it. I was paper, perhaps may have received the
consulted, and I suggested that these impression that concentration, as it is
various activities be combined into one true in most of the ordinances around
' division, called the Division of Air Pol the country, is used independent of
lution Control. At present we have in either the volume of gas discharged, or
this division three bureaus: one, of the magnitude of the operation, or the
course, the basic industrial hygiene number of stacks per unit of ground
bureau; second, the industrial nui- area, or any other rating devise you
: sances, which takes care of all the com might use.
plaints arising from discharges into the The fact remains that a very, very
free atmosphere from The various of small volume of discharge at several
fending plants; third, smoke abatement, times the permissible limit may still be
DUP050314465
110 DISCUSSION
a rather insignificant source of trouble in the community. Naturally, therefore, it is necessary, I think, in most of these problems, to make it clear early that possibly tremendous volumes of contam inated gas discharged at less than the standard concentration might be more troublesome than a, few minor sources that are obviously above the limits.
I would like to have some comment from Dr. Fredrick at this stage, who is now director of the Bureau of Industrial Hygiene in Detroit, and in connection with the Detroit program of smoke abatement and pollution control, has provided the technical assistance to the Smoke Abatement Division in matters of air pollution investigation. Dr. Fred
rick. Dn. Wil l ia m G. Fr e d r ic k [Bureau
of Industrial Hygiene, Detroit Depart ment of Health, Detroit, Mich.]: The matter of basing limits on stack dis charge is the only satisfactory solution to the problem. The concentrations of contaminant out in the general atmos phere become so low that they practi cally defy our present analytical tech nics.
It is possible to solve the problem, but the expenditure of time required is disproportionate to the facilities that are available for doing the job.
I think most of us who had to suffer with the problem of measuring the amount of contaminant in the general atmosphere will he in agreement. If wc can base it on the source of contamina tion, the measurement problem becomes much simpler and, after all, that is the point where it is going to have to be controlled anyway.
There is another comment I would like to make. In all of the ordinances which have come to my attention, at mospheric contamination values and stack loading values are expressed in a queer and archaic system of units and
nomenclature.
.
The use of the metric system of
nomenclature in atmospheric pollution
work in general, particularly in the in
dustrial hygiene and health field, is well
established. We use the milligram per
cubic meter nomenclature or the milli
liters per unit volume nomenclature.
The use of grains per cubic foot or
ounces per cubic foot or pounds per
cubic foot is a very awkward and in
consistent system of nomenclature, and
I believe that the ordinances should be
revised. It will save the chemist from
making recalculations, and it will cer
tainly make it possible for people who
are, in general, working in the field, to
really understand the magnitude of the
limit.
The figures which I notice in the
manuscript here this morning are quite
incomprehensible to me, unless I get
out a slide rule and apply a few factors.
Ch a ir ma n Bo w d it c h : I would like
to add to what Dr. Fredrick has just
said with the comment that, while I was
in Los Angeles and was talking with
one of Dr. McCabe's chemists, I asked
him what these regulations meant in
terms of out more usual nomenclature
in industrial hygiene. He replied that
he hadn't the foggiest idea, but would
be very glad to sit down with a slide
rule and figure it all out for me.
Dr . Mc Ca b e : We went through this
argument. On one side we had the en
gineers and on the other side we had
the industrial hygienists and the chem
ists. The engineers finally won out.
The question of who is going to use the
slide rule is, I think, what you have to
decide.
Mr . Wit h e r id g e : You need two col
umns of data, so that nobody needs to
use a slide rule.
It is interesting to me to find on one
program discussions both of indoor con
tamination problems and outdoor oon-
DUP050314466
AIR POLLUTION
111
tamination. I think those of you in die industrial hygiene field have been, for some years, conscious at least of poten tial, and sometimes real strains that can develop between those who are trying to clean up the inside of plants and the other regulatory groups trying to clean up the neighborhoods .of plants, which is one of the reasons I stated earlier that Mr. Dyktor has the thing really under
his thumb. Investigators who have worked pri
marily on the inside of plants, neverthe less, as a result of the work they have done with rather specialized and elab orate devices, and trace-analytical pro cedures. have been called upon to study outdoor problems as well. The experi ence of most of those who have been in the field for years has been that, by force, whether they had an original in terest in the problem or not, they have had to develop one and comply with some of these demands, and that, in so doing, a great deal was learned about the simultaneous control of contamina tion, both inside and outside of the plant, which is really the best way of approach.
1 would suggest that we have a few comments at this stage by Dr. Sappington who has been a veteran industrial health consultant for many years and has expressed to me the fact that a good many of these outdoor pollution prob lems have been brought to him for study. Dr. Sappington.
Dr . C. O. Sa p p in g t o n [Industrial Medical Consultant, Chicago, 111.]: Mr. Witheridge, I certainly want to make this short, because the hour is quite late.
My experience in this field is almost entirely limited to the medicolegal as pects of it, which are highly contro versial. However, I see, both as a phy sician and an industrial hygienist, that there are certain parallels in industrial hygiene codes and in the regulations for
atmospheric pollution. _ I think it might be well, and I do
make the suggestion seriously, that those who are devising regulations or codes, as you may call them, for preventing atmosphere pollution, or controlling it, might very well share their experiences with those who have been working on
industrial hygiene codes. I would like to make just two refer
ences here. These may be old to most of you but I found them very helpful. Con cerning the remark that a great deal of "hokum" has been written on this sub ject, as well as on lead, I would like to cite two references which I believe will be quite helpful. One is "Atmospheric Pollution by Heavy Industry" by E. Wendell Hewson of Toronto, published in Industrial and Engineering Chem istry, March, 1944, in which he tells about the conditions at Trail, British Columbia. The other one is also en titled "Atmosphere Pollution" by our friends Hemeon and Hatch, also in Industrial and Engineering Chemistry, May, 1947.
I feel that there are certain very basic things in these two references which those of you who don't know about might consider.
Mr . Wit h e r id g e : Thank you verymuch, Dr. Sappington.
In justice to the following speaker, I believe that all further comments on this subject should be deferred until after the luncheon, because we have a period for discussion this afternoon and this subject can then perhaps be the target of further comment.
Ch a ir ma n Bo w d it c h : Our final paper on the morning program will be by the Assistant Professor of Medicine, Uni versity of Colorado Medical Center, where he was largely responsible for one of the few scientific appraisals of aluminum therapy that has thus far been made. Dr. John W. Berry.
M--a
DUP050314467
ALUMINUM AND SILICOSIS
By JOHN W. BERRY, M.D.
Assistant Professor of Medicine, University of Colorado Medical Center, Denver, Colo.
Since Denny, Robson and Irwin pub
lished their historic papers in 1937 and
1939, those interested in silicosis have
been anxiously anticipating information
derived from study on the human which
would allow them to fit these experi
mental observations into their proper
place in the management of the silicosis
problem in industry and in clinical
medicine. Since the first of these papers
appeared over eleven years ago, it would
seem that considerable useful informa
tion should now be available; such is
largely not the case.
.
The answers to certain very important
questions must be known before it will
be possible to determine what part, if
any, aluminum inhalations are to play
in the treatment and prevention of sili
cosis. We must know the effect of
aluminum on man, the effectiveness of
aluminum in the prevention of silicosis,
the effect of aluminum in patients dis
abled by silicosis, and the effect of
aluminum in doses that are used pro-
phylactically and therapeutically on
tuberculosis. Partial answers to these
questions are available.
The fact that aluminum is very prob
ably harmless to the human lung can
be inferred from the following informa
tion. You are all probably familiar with
the frequently cited observations made
at the Aluminum Co. of America in
which the study, both clinical and of the
chest x-ray films, of 125 men who had
been exposed to very great concentra
tions of aluminum dust for many years,
failed to disclose any pathologic change
which could be attributed to the alumi
num. The British Medical Council, after
reviewing the findings of 50 workers
exposed to aluminum in high concentra
tion over a long period of time, were
112
able to report in 1936 that there was no evidence of pathological change due to the inhalation of aluminum dust. Hunter, Milton, Perry, and Thompson studied persons who were engaged in the grind ing of aluminum propellors during the war, and again there is no evidence that aluminum was in any way toxic. For the past several years in English pot teries, aluminum has been substituted for quartz in the manufacture of dishes. In this operation a large number of men have inhaled considerable aluminum over a period of years, and again there is no evidence that aluminum is patho genic. Finally, in the United States, Canada and other countries, many thou sands of men have inhaled aluminum dust as a prophylactic and therapeutic agent in silicosis, and in these cases there is no convincing evidence that aluminum has caused any pulmonary change.
On the other hand there have been several reports from Germany in which a peculiar pulmonary disease has oc curred in persons exposed to large quan tities of aluminum. While aluminum has been thought to he the agent respon sible for this condition in Germany, there is no proof of this. Follow-up studies on these cases and on this prob lem are now being carried on by English investigators; the final answer is not available. Recently Riddell and Shaver have reported a peculiar pulmonary disease occurring in men who have been
exposed to large quantities of aluminum. These cases closely resemble those which have occurred in Germany. Again, in none of these cases has aluminum been proved to be the etiologic agent; in fact there is considerable doubt that alumi num is responsible for these cases, but
DUP050314468
mr
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P" 5 g
ill
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i
ALUMINUM AND SILICOSIS
113
it is well to keep these reports in mind.
will be granted is that proper dust
In spite of this it is probably safe to control be instituted in plants in which
assume that aluminum, as it is used pro- there is a silicon hazard. It is only after
phylactically and therapeutically, is safe. the dust in the plants has been con At least there is no convincing evidence trolled to the satisfaction of the McIn
available to show that aluminum has tyre people that aluminum inhalations
in any case been harmful.
are allowed. If dust is suppressed prop
In regard to the prevention of silicosis erly, there will be rio silicosis, and there
by the use of aluminum, I think that fore one cannot use such groups to judge
it has been established beyond a reason the effect of aluminum if in reality there
able doubt that aluminum in the proper compounds and in adequate dose will prevent the development of silicosis in
is no silicon hazard. However, in many situations adequate dust control is very difficult; for this reason there may be
experimental animals. This has been some justification for the use of alumi
well demonstrated by Denny, Robson num in the plants. But, when it comes
and Irwin and amply confirmed by to using statistics derived in this way to
Gardner and his group at the Saranac prove the value of aluminum, one cannot
Laboratory. There are two reports in tell which of the two factors is respon
the literature which tend to cast some sible for a reduced incidence of silicosis,
doubt upon 'this conclusion, but I think the dust control or aluminum. For this
the failure recorded by these men was reason it is impossible to use the inci
due to experimental difficulties, rather dence of silicosis before the institution
than to failure of aluminum.
of aluminum and that afterward to form
Shortly after the discovery that alumi an opinion as to the effect of aluminum.
num would prevent silicosis in animals, In order that I am not misunderstood, I
several projects were started to test its am not suggesting that dust control be
effectiveness in the human, both in the neglected and aluminum substituted, but
prevention and for the treatment of silicosis. But in spite of the fact that several thousand men have received
I only wish to point out that in this situation the effect of aluminum will re main unknown. In view of these facts,
prophylactic aluminum inhalations, it is it has been suggested that since some
impossible at this time to arrive at any men will refuse aluminum inhalations
conclusion. There are several reasons and they will work in the same environ
for this. First of all, silicosis is a disease which develops very slowly and there has been insufficient time in most in stances to evaluate its prophylactic value. But aside from the time factor, I have
ment with those taking the aluminum, that the incidence of silicosis in these two groups be compared in order to form an opinion as to the effect of alum inum. This plan has many possibilities
considerable doubt as to whether we are going to be able to evaluate the prophvlactic value by the use of the results of the work now under way or already reported. The entire procedure, as you undoubtedly know, is patented by the
of error and is very comparable to the control system used in the early work with BCG, and I am sure that you are familiar with the doubt and indecision surrounding BCG. Men who refuse to take the aluminum can reasonably be
McIntyre Research Ltd., and in order to use aluminum, a license from the Mclntyre Research Ltd. must be secured. One of the conditions upon which a license
expected to be the same men who would deliberately violate any measure for dust control which depended upon workman execution, and for this reason this is a
(ft
mam
DUP050314469
114 BERRY
group in which silicosis is most likely to occur. Therefore, in my opinion the use of this sort of control will of neces sity weigh any statistics very heavily in favor of aluminum. It seems to me that in order to arrive at the answer to this problem, it will be necessary to do scien tifically controlled. experimentation by means of large numbers of men over a long period of time, during which time the magnitude of the silicon hazard is known. These men must be divided into two groups, not haphazardly, such as using those who refuse inhalations, but by some deliberate plan so that by chance we would have comparable groups. It is only by use of this or some other similar plan designed to be as nearly foolproof as it can be made, that we will arrive at a reasonable con clusion in regard to the value of alum inum in the prevention of silicosis. Most of the work reported to date is actually of no scientific value, except perhaps to demonstrate the safety of aluminum in halation. I realize that there is little reason to think that aluminum will not be as effective in man as it is in the ex perimental animal, but until it is proved to be as effective in man, we cannot accept it without reservation.
The evaluation of the therapeutic ef fect of aluminum in silicosis is as diffi cult as or more difficult than is the evaluation of the prophylactic use. In the reports available, there are many cases described as disabled by silicosis without a clear definition of what is meant by disability. It should be noted, however, that many of the persons said to be disabled were able to work, and I think these cases more properly should have been called symptomatic cases of silicosis, or described as partially dis abled with a note as to exactly what is meant by partial disability. In the main, the improvement reported in the litera ture is subjective improvement. In other
words, the patient, thinks that he feels better. I think it is fair to compare such evaluations to the testimonials we fre quently read in newspapers which are used to prove the' value of many nos trums. The silicotic has a disease which has frequently caused the deaths of many of his friends and associates and for which there was no hope of treat ment until aluminum was introduced. If we remember this, it is easy to under stand how the administration of an agent thought to help silicotics will brighten the outlook of these individu als. For these reasons we must turn to the reports in which there has been some attempt to determine the effect of aluminum by objective methods.
The early report of Blaisdell, Crombie and MacPherson described the pulmo
nary function tests used by them. The tests used by them were apparently as good as are available at the present time. By means of these tests they showed that five of their treated men showed definite improvement in pulmo nary function. However, one member of their so-called control group also showed significant improvement in pul monary function. In view of the fact that the treated group was much larger than the untreated group, the percentage of those treated showing improvement was 14.7 and of the untreated group, one patient amounted to 12 percent of the untreated group. They do not give the specific results of their tests, and in view of the fact that one man who had received no aluminum and had not even been subjected to the same suggestive management as the treated group, showed improvement, I think we must be very skeptical of this reported result, especially since the percentage of im provement is almost the same in both groups. Hannon, in a recent report, claims 80 percent of the treated patients showed at least 20 percent improvement
DUP050314470
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ALUMINUM AND SILICOSIS
115
in their "respiratory effort." He does not say specifically which tests of pulmonary function were used, but I presume it was the maximum breathing capacity. He did not test those who did not claim im provement; at least he makes no report of such tests. Wright at the Saranac Laboratory has done physiological stu dies on pulmonary function in men treated for silicosis, but he can demon strate significant improvement in only 5 percent. In addition to silicotics, Wright has taken another group of men who, although they were not silicotic, thought they had the disease. He treated these men with aluminum and could demonstrate considerable subjective clin ical improvement in them.
At the University of Colorado we were skeptical of the value of aluminum in the relief of disability when it was due to silicosis. We undertook a study which I will briefly summarize, although I have little to add to the published re port. We selected a group of 42 sili cotics because they were disabled to varying degrees by their silicosis, be cause they had no compensation claims which would tend to color their symp toms, and because they were free of demonstrable tuberculosis. At the onset of this work we did not use a control system because we thought that by con ducting the experiment for a sufficient period of time we would be able to de termine the real value of aluminum, but as the work progressed it became obvi ous that we would never arrive at any answer without a control group, since those receiving aluminum were so en thusiastic and believed themselves to be so much improved, in spite of obvious deterioration of health of some cases. For this reason we altered the apparatus by which the dust was administered so that we could allow certain men to go through the same routine but receive only air from the machine. These men
who were selected as,controls did not know, of course, that they were not re ceiving aluminum. Soon after the initia tion of the control system we felt that our skepticism was justified, since im provement very comparable to that ob served in the men who had received aluminum became evident in members of the control group who had received no aluminum. In the early part of our work, after a few inhalations of alum inum, men who were unable to walk up stairs previously, were able to do so. This was very impressive, but after we initiated the control system, we noted the very same improvement in the men who had received only air. To be cer tain there was no accidental contamina tion of the air by aluminum, we checked the control outlets and found no signifi cant amount of aluminum in the air breathed by the controls. We used only the amorphus hydrated alumina XH 1010 as recommended by Gardner. The men received on the average a total of 130 treatments, spread over a period of one year. The men breathed an atmos phere containing 300,000,000 particles of alumina per cubic foot. The particle size averaged 1 to 3 microns in diame ter. How much of this dust reached the alveoli is unknown.
Since the conclusion of this work in January, 1948, I have had the oppor tunity to examine a few of these men. Members of both the control and the treated groups continue to state that they have been definitely helped by this treatment. This is true even when it is obvious that the man's health has de teriorated, The most interesting of these cases is one to whom I talked two weeks before his death, at which time he was very firm in his conviction that he had been improved. At the time of this ex amination he was extremely dyspneic, had a large liver, very marked ankle edema, and it was obvious that he was
ill
I
DUP050314471
no BERRY
seriously ill. Following death I was un without detectable harmful effects. Dr.
able to secure postmortem examination, Hannon has told me that he has treated
but it seems to me reasonable to suppose a few cases of silico-tuberculosis with
that he died of pulmonary insufficiency reduced doses of aluminum without any
which precipitated the right heart fail demonstrable harmful effects. These
ure. Several other men who received cases certainly form an inadequate basis
aluminum at the University of Colorado upon which to rest an opinion as to the
have died, but I have been unable to effect of aluminum inhalations. It may
secure postmortem examination, since be interesting to note in this connection
their home is usually at some distance that in a report by Dr. George of Austra
from the school and I have not learned lia, he cites some work by Gardner in
of their death until after their funeral.
which animals with silico-tuberculosis
Most of those interested in aluminum were given aluminum which seemed to
therapy have recommended that the in prolong their life without actually influ
halations should not be given to persons encing the course of the tuberculosis.
who have obvious evidence of tubercu
It is generally accepted that silicotics
losis or in whom there is found reason frequently become tuberculous. This
to strongly suspect the presence of tuber view has been challenged by Ornstein
culosis. The reason for this is based and a few others, but the vast majority
mostly upon the work of Gardner and of those who have seen large numbers
his group, in which they demonstrated of silicotics are convinced beyond any
that the administration of large amounts reasonable doubt that tuberculosis com
of aluminum to animals decreased the plicated a high percentage of cases. The
resistance of those animals to tubercu reason for the unusual frequency of tu
losis. The doses used in these experi berculosis in these patients is unknown.
ments were far larger than any used in We do know that the presence of silicon
the prophylactic or therapeutic adminis in culture media will cause the tubercle
tration of aluminum.
bacilli to grow faster and more luxuri
The only reference in the literature antly. It is also known that the presence
which I can find which suggests that of silicosis in animals will cause such
the inhalation of aluminum in the hu animals to exhibit less resistance than
man leads to premature development of normal to the tubercle bacillus.
tuberculosis is contained in the report
Although the solubility theory of the
of King and Sutherland to the British pathogenesis of silicosis is not univer
Research Council in which Dr. William sally accepted, it would seem to me to
Taylor of the Workmen's Compensation be the most reasonable assumption to
Board of Timmins, Ontario, states that explain the pathogenicity of silicon di
he believes two cases have developed tu oxide available at the present time. It
berculosis possibly as the result of alum would also seem to me, in view of the
;:i inum inhalations. King and Sutherland fact that tuberculosis complicates sili were not convinced that these cases of cosis in any stage, that the decreased re silico-tuberculosis were in any way un sistance to tuberculosis must be in some
usual, and there was no proof that they way connected with the soluble product-,
were due to aluminum inhalation. On of silicon dioxide. If this be the case, and
the other hand, in the report of W. E. if aluminum is capable of decreasing the
George on a visit to the United States, solubility of silicon, then perhaps the use
he quotes Dr. Crombie as saying he had of aluminum, while of little value in re
treated persons with silico-tuberculosis lieving the symptoms due to silicosis,
DUP050314472
may possibly prevent die development of tuberculosis in silicotics. I realize that the weight of evidence as it is known at the present time is heavily against the probability of this idea and I make this suggestion somewhat in desperation be cause of the disastrous effect of tubercu losis when it occurs in die presence of silicosis. I am aware of the fact that in a few cases tuberculosis has become first evident either during or following alum inum inhalations. But I am of the opin ion that if there is the slightest chance of reducing the incidence of tuberculosis by the use of aluminum, we should take that chance, since we have nothing else to offer these men. In our very small group at the University of Colorado, there was no instance of tuberculosis in the treated group either during or fol lowing treatment. This applies only to those whom I have had an opportunity to examine, approximately half the group. During the same interval a smaller group of controls who received no aluminum showed two cases in which the onset of tuberculosis occurred many weeks after the beginning of the experi ment
In summary I should like to say that because the results in animals are so striking, the value of aluminum in the prevention of silicosis in the human should .be determined, but in my opinion the methods used at present probably will not produce the answer. If alum inum proves to be helpful in die preven tion of silicosis, even then it should not be used in preference to dust control. This may prove to be a real danger be cause of the expense of an adequate dust control program. It has been sug gested that aluminum be used in two distinct situations: first, in those indi viduals who develop silicosis in an en vironment which is safe for most workers, or develop silicosis after an abnormally short period of exposure;
and secondly, where the industrial situa tion is such that dust cannot be con trolled for short periods of time. In regard to the first group, I am sure that there are those who develop silicosis more rapidly than the average for an unknown reason, but in my opinion the majority of such people fall into one of two groups: those who are mouthbreathers or because of nasal pathology their nasal mucosa is not as effective as normal in protecting the respiratory tract, and those who must take in to their chest an abnormally large amount of air to secure a given amount of oxy gen. Into this group fall such diseases as chronic asthma, chronic bronchitis, and other pulmonary diseases. Men with these ailments should he excluded from employment in dusty industries. Be cause this would reduce the number of men who developed silicosis in an en vironment which is safe for most work ers. In the second group, it is true that there are instances where it is not pos sible to constandy control the dust, but these of course should be held at a min imum before aluminum is used.
I think there is very great doubt that aluminum inhalations are actually capa ble of relieving the symptoms of sili cosis, but there may be a remote possi bility that by the use of aluminum the incidence of tuberculosis in silicotics can be reduced. There is no experimen tal basis for this opinion.
Early in the course of this work it was hoped that aluminum would stop the progress of silicosis, if it did nothing more, but there is some evidence that it does not halt die disease. In the report of King and Sutherland previously quoted they mentioned the fact that Drs. Riddell, Cunningham and Taylor have noted that in the cases reported by Crombie, Blaisdell and MacPherson 23 out of 46 treated cases have progressed. This progression was evident in some
DUP050314473
1X8 DISCUSSION
who had claimed they were Letter. Rid dell mentions that other cases had pro gressed in spite of aluminum adminis tration. Therefore we are forced to conclude that aluminum, in some cases at least, does not halt the progress of silicosis once the disease is established.
Ch a ir ma n Bo w d it c h : The discussion of Dr. Berry's paper will be led by one
of our leading authorities on silicosis, especially in the foundry industry. He has probably the most extensive collec tion of roentgenograms of this disease in the United States, has written very extensively on the subject, and is con sultant to many industries throughout
the country. Dr. 0. A. Sander of Mil waukee.
DISCUSSION
Dr . 0. A. SANDER [Milwaukee, Wis.]: All who are interested in this matter owe a debt of gratitude to Dr. Berry and his co-workers in Denver for this clear-cut and well controlled investigation. Ac
tually it was the first and still is the only scientifically controlled study of the ef fect of aluminum in human silicotics. It is the only human experimentation from which any valid conclusions can be drawn. What we long suspected was proven beyond doubt; i.e., that it was not the aluminum which was responsible for the subjective improvement claimed by some 65 percent of silicotics so treated. Sugar pills would have accom plished the same results had they been publicized as the long-sought-for cure.
This evidence should not halt all fur ther investigations, however, into the possible therapeutic value of aluminum. There still is the group of cases, small in number but tremendously important, in which silicosis develops rather rapid ly. Where one finds a sandblaster, for example, as I did recently, who last year had only increased trunk and linear markings on his chest film and this year has a well developed nodulation because he had had a defective helmet which was not properly maintained, any therapeu tic measure which offers even the most minute ray of hope of arresting the almost certain progression of his sili cosis should be attempted. There is evidence now, as stated by Dr. Berry
in quoting Drs. Riddell and Cunning ham, that metallic aluminum is not halt ing such progression very effectively. The hydrated alumina and colloidal alumi num hydroxide, however, may be more effective with such cases. This statement is based on animal work at the Saranac Laboratory from material as yet unpub lished. In a recent communication from Dr. Vorwald, he stated that there was marked arrest of the silicotic changes which precede the formation of fibrous nodules when such animals were exposed to hydrated alumina. Comparable pro tection was not observed when similar prenodular silicotic animals were exposed to the metallic aluminum. Unfortunate; ly, for the purposes of experimental evaluation at least, such rapidly develop ing silicosis is very rare today. Present evidence, however, suggests that the hy drated alumina should be started at once on such cases when discovered, provided a tuberculous background for the rapid progression can be ruled out.
As for the general prophylactic use of aluminum in foundry workers, I should like to say a few words about that. As a result of the aluminum publicity sev eral years ago, there were demands from many foundry employees in our area for an aluminum dusting program. I have consistently discouraged them for sev eral reasons. First and foremost, found ry silicosis can be prevented and is being prevented today by adequate dust con-
3
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DUP050314474
ALUMINUM AND SILICOSIS
119
trol. We see only very occasional cases of new silicosis developed since the con trol programs have been enforced, such as occasional sandblasters whose pro tective equipment has failed. Such cases can be treated individually. I visualize more harm than good by an over-all dusting program because laxity in dust control is bound to creep in no matter how rigid the rules.
The other reason I have discouraged aluminum dusting for foundries is that the atmospheric dust in foundries is always mixed and already contains com ponents which have been shown experi mentally to be almost as protective as aluminum. In foundries today, the silica content seldom exceeds 20 to 25 percent, with 35 percent as the upper limit in the poorest controlled foundries. That means that 65 to 80 percent of the dust which foundry workers breathe tends to prevent or at least modify the reaction of the silica they are breathing. These other components are primarily iron and carbon. It hardly seems necessary to add another component to such mixed dusts. The only exception, as already stated, is the occasional sandblaster who through equipment failure develops a rather acute silicosis. His exposure to free silica has been too excessive for the
mixed dust in the general foundry to
be at all protective. In closing, I agree in every respect
with Dr. Lanza's statements in his ex cellent editorial in the American Review of Tuberculosis of June, 1948 and I recommend that all who are interested in this matter read it. In the same issue,
by the way, is Dr. Berry's first paper
on his work, which also is fascinating reading. I quote from Dr. Lanza's edi
torial:
"It is to be hoped that further con trolled studies will be forthcoming, and that the propagation of the alumi num treatment will be stayed until further information as to its effects is available. It is especially desirable that the possible beneficial effects on early stages of silicosis be thoroughly explored. The continuation of present practices will tend only to cause fur ther confusion and, in the long run, may defeat the purposes which the Canadian group originally had in mind."
Ch a ir ma n Bo w d it c h : We seem to have about 15 minutes to go. Who would like to add a contribution to the dis cussion of this subject?
Dr . Da v id R. Jo h n s [Consultant, American Smelting & Refining Co., Eagle-Picher Co., and Glidden Co., East Chicago, Ind.]: Mr. Chairman, all I would care to say at this time is that we have been trying out aluminum therapy at two plants, but on a large scale in one. Our five-year period will shortly be up. I am concerned about a man who has secondary or third stage silicosis and who is terribly disabled, but I do not believe that you can change scar tissue or fibrosis. My concern is with the possibility of slowing up these men who have reached a 2+ or a potential pri mary silicosis, and we are now complet ing a five-year period.
Wc see nothing in our observations at the present time to discontinue the use of aluminum. We are going on with it, and we expect to publish what we feel we have seen in that five-year period.
I might say that we are treating about 1,200 cases at the present time,
Ch a ir ma n Bo w d it c h : Are there fur ther comments on this subject? If not, we will continue after lunch.
.
DUP050314475
TUESDAY LUNCHEON SESSION
NOVEMBER 16, 1948
Ch a ir ma n Bo w d it c i-i : When I was arranging the program for this confer ence, I got to thinking about the Saranac Silicosis Symposiums of the 1930s and the summations that my old and good friend Roy Gardner made at the close of those Symposiums, and I found my self wondering who could do the same for us at this conference. Rather na turally, I thought of another equally old and good friend, not only of Dr. Gard
ner's but of mine. I asked him to perform this service for us and charac teristically, he consented.
To anyone who knows anything about industrial hygiene, he needs no introduc tion whatsoever, so I name him to you, as he was affectionately designated at the time that he received the Knudsen Award for outstanding service to indus trial medicine, Tony Lanza.
SUMMATION OF CONFERENCE PROCEEDINGS
Dr . An t h o n y J. La n z a [Associate Medical Director, Metropolitan Life In surance Co., New York, N. Y, ]: Mr. Chairman, ladies and gentlemen: In the course of an active and sometimes dis oriented career, I have attended all kinds of meetings. I feel this is one of the best meetings which I have ever attended. I think it is good because I learned something, and, strangely enough, I think that is why most of us
come to meetings of this sort.
I have learned a lot in the last two days, and it is valuable knowledge. One thing that this session has emphasized wisely is that, in this whole matter of industrial health, you are dealing with two skills -- medicine and engineering. I do not think that either one is more important than the other. But, on the other hand, I will say this. The doctor by himself can do a pretty good job, the engineer by himself can do a pretty good job, but only by working together and appreciating each others' responsi bilities and points of view can they do the sort of rounded-ouL job that the
120
exigencies of industry [when I say "in dustry" I use the word as an all-inclusive term, embracing both the employer and the workers] demand.
I want to touch briefly now on some of the high spots of this meeting, as they seem to me.
Dr. Harrold put his finger on some thing, when he spoke about particle size. I have been in this business quite a long time, and for a number of years we
used to talk, and we still do talk, rather
glibly about particle concentrations in the atmosphere, and so many million particles per cubic foot, or so many milligrams per cubic meter, and we thought that we knew everything there was to know about particle size.
T made this kind of a statement over and over again [there is nothing like eating your words once in a while, you know]: that it took very small particles, to get into the lungs, that most of those that did damage were probably below 5 microns in size. That is all right; I go along with that yet. Also, when you got down below half a micron, or some-
DUP050314476
_
SUMMATION
121
where around that, these sizes did not have much significance; that they floated in and out with the tidal air and were not of much concern. I think probably that statement is as erroneous as any thing can be. In these questions of dust pollution, whether you are talking about substances that act like silica, asbestos or diatomaceous earth, or substances that act like lead, maybe the electron microscope is going to change a lot of our thinking. I am beginning to think now that particle size is one of the things about which we know extremely little, and yet which may be-the determining factor in some of these questions that puzzle us; why we get contrary evi dence on clinical examinations or on laboratory examinations of people who we think are exposed to the same type
of hazard. : Dr. May R. Mayers, with that charac teristic good sense that always distin guishes her, uttered a truism that we should always remember, and that is that we must consider the patient as a whole.
Somebody said, in talking about that at our meeting, that the laboratory find ings often do not indicate the serious ness of the condition.
You hear a lot about industrial medi
cine and industrial hygiene nowadays, and that it is a branch of public health or that it is a branch of preventive medi cine, and so on. These statements are partially true, but, after all, tlie physi cian and the engineer, and particularly the physician who gives his time to in dustry is dealing with people just as much as the general practitioner up the block who takes care of little Susie or Johnny or the boss or his wife. They are dealing with people. That is why, as one of your commentators said yester day, the patient-physician relationship is so important. I think it was Dr. Belknap who said that.
Then our old friend Dr. Johns made a statement, the importance of which I do not know whether you all appreciated when he said it. What did he say? He said, "I visit my plants. I visit my plants every week."
You know, I get a lot of diagnoses, made by presumably good men who are supposed to know their business. They make these diagnoses by adding up two and two and getting fourteen. They would not make these diagnoses if they were familiar with the conditions under which their patients worked; they could not make them. But, as Dr. Johns said, he visits his plants, and that is why he is a successful industrial physician today.
I am no expert on lead poisoning. I
have seen very little of it. But it seemed to me, in listening to the discussions yesterday, that there was a general agreement on the treatment, and I could not hear that there was any very active opposition to the statement by Dr. Wilentz that deleading is dangerous; he did not believe in deleading. As far as I know, that statement went unchal lenged by the persons here. I think one did say that it was of doubtful value, but apparently the general opinion was that it was not good practice.
There was general agreement that there is much mild lead poisoning, that there is not much aggravated or severe lead poisoning, and that most of the ill effects of lead are found in the small plants and among the occasional users. I think that is absolutely true. Our own experience seems to bear that out. Yet every once in a while, you know, it crops up in a way that takes you competely by surprise.
Some time ago I had occasion to visit a plant where the amount of pre sumably nonoccupational illness was ex tremely high, and most of it fell into the general classification of gastro-in-
J
DUP050314477
122 LANZA
testinal diseases. I thought that looked funny because, as you gentlemen know, the general American ratio of sickness among the population is three cases of respiratory to one gastro-intestinal. That seems to be about the American average.
In this particular plant it was the other way around,,, three times as many gastro-intestinal cases as there were res piratory.
I went down to see this plant. It was a perfectly beautiful plant. It was fairly new, beautifully laid out, designed, ven tilated and illuminated. Everything was top notch, but one item was wrong.
One of the prime operations consisted of the assembly of small parts, which was done by girls working on each side of a long table with a moving belt down the middle. They assembled the parts, and then they were moved up to the end of the table, and at the end of the table was a man who had a lead pot, and he soldered them. Here was the wall with the windows, and the windows were all open. It is perfectly obvious what happened.
The fresh air, the sunshine and every thing was lovely, but the fresh air blew all the fumes from the lead pot right on down the table; they leaded everybody in the place, from cellar to garret. They did not miss anybody but the superin tendent, and I was not sure about him. None of them had wrist drop or colic, or anything like that, but did lose their appendixes and a few of them lost their gallbladders, too. So, you never know.
Dr. Gray touched on something that I think is giving all of us a great deal of trouble and a considerable amount of worry, and I am quite sure that I have not got the answer. But Dr. Gray, in the course of his comments, said that the physician on call does not have the time nor is he paid to inspect his plant.
Golly, how true that is! And how
much trouble and how much mistaken diagnosis and how much poor practice is covered in that sentence!
This morning I listened more or less entranced by the discussion of Dr. Eagle and Dr. Corwin, well considered, judi cious expressions of opinion, founded on research principles and sound re search procedure, talking about BAL. I thought it a very careful and very scholarly presentation.
As I listened to their discourse and looked at those fascinating cartoons of Dr. Corwin's, the thought occurred to me that maybe two years from now, if we were looking over the bound pro ceedings of this meeting here today, probably we would think then that that joint presentation was the high spot of this meeting.
The subjects of the coordination of medical services and of the role of the state agency with respect to the control of working conditions, I think were very amply and very ably covered by persons who had had a great deal of practical experience in those fields.
The state has an interest; the com munity has an interest. I sometimes think that the poor working conditions and certain amount of turmoil that are seen at times, where the industry is off the beaten path, are due to that fact, that it is away from our common knowl edge.
Then this morning we heard Dr. McCabe from Los Angeles. I was out on the West Coast for four months last year, and I spent some time down in Los Angeles. I was interested in the synthetic rubber plants that have been erected south of the city. That was right after one of the outbursts of smog and popular indignation and the mild de gree of hysteria that goes with that sort of event. You know, nothing makes peo ple so unhappy and gets them so excited as something that smells bad. If you
DUP050314478
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SUMMATION
123
If have ever noticed it in your working atmospheric pollution and the dirtying A conditions, they will eat silica dust, they of their silks and rayons and linens and
jj will eat lead, they will deal with any whatnot, all of which, of course, is thing, but let something smell bad, and, passed on to the consumer. You under
brother, they are right up in arms! It stand that. But we believe that the next
is peculiar, but it is the truth.
great forward step in public health in
I was fascinated by Dr. McCabe's this country is going to be in connec
description of the interplay of meteoro tion with the control of atmospheric
logical conditions and the exhausts from pollution.
the stacks of different types of industries.
Far be it from me to comment on the
He made it very clear as to why what interesting remarks of Mr. Witheridge,
i happens, does happen. The remedy, of Mr. Dyktor and Dr. Fredrick, because
course, is not so simple.
they were in realms in which I have no
But, on the other hand, in talking to experience, but it seemed to me that the
students in recent years, I have com indications are clear that everybody is
monly made this observation: the Ameri beginning to get disturbed, and the sort
can people have been educated to spend of thing that happened in that little town
enormous quantities of money on pro in Pennsylvania the other day, regard
viding their communities with good less of how correct the newspaper ac
drinking water. You can take an auto counts may be, is going to stir things
mobile trip from Maine to California, up quite a lot.
or from Florida to Seattle, and you will
Well, that brings us to the last paper
stop at all kinds of places, big city on the agenda this morning, the one on
hotels, tourist camps, tourist boarding aluminum therapy. It must be twelve
houses, roadside diners and whatnots, years since Dr. Roy Gardner, Dr. R. R.
and vou can feel almost certain, when Sayers and I first went to Timmins, On
they put a glass of water in front of tario, to see their demonstration of this
you, it is fit to drink. To be sure, it aluminum.
may taste a little of chlorine, but one
We spent a day at the Banting Insti
' .v
cannot be too finicky about that.
tute. Dr. Banting was alive then, of
The reason that is so is because the course. I was very much impressed --
American public has been educated to we were all impressed -- with the people
demand good drinking water. They who constitute McIntyre Research, Ltd.
have not been educated to demand good I think they are an awfully good bunch
air. They are just beginning to wake of fellows. I think they are absolutely
up to the fact that maybe they can do on the square.
something about atmospheric conditions,
Well, I think the whole aluminum
and that it is not necessary to have their question is beginning to lose some of its
community, including the places where point, but I will say this, that Dr. Berry
their homes are, blanketed a good many presented a well-balanced, well-consid
days a year with a lot of fog and smoke. ered, fair paper. I thought it was an
The people who run the department honest and fair statement, and he and
stores have been screaming about it for his associates are in a position to make
years, because the economic loss to them a well-balanced statement, because they
is terrific. We talked to some of the de have done a well-balanced job. Hind partment store people in Pittsburgh, and sight is always better than foresight.
you would be quite surprised to learn
I think there have been a lot of mis
the extent of the loss to them due to takes made in the whole way this alum-
-- * *
DUP050314479
124 LANZA
inum business was handled. I am not critical of it, particularly. I simply feel that conditions in industry are such that you cannot run a scientific experiment or a control where your people are go ing and coming, and they are here today and gone tomorrow, and you never see them again. How,can you follow them up? How can you know what happens to them? You don't. It might be pos sible if you were dealing with an acute condition, but not a chronic condition that may take fifteen or twenty years to develop.
I am only going to say one thing more
about this. The last time I was in To ronto", and I went up there at the invita tion of the McIntyre people, I made this observation to them.
I said [and, mind you, I do not ques tion their motives in the least], "You have been running this thing now for going onto eleven years. You must have learned something. I think that, inas much as you are spreading it and have
set up machinery to introduce it around industry -- in other words, out pushing it -- I do think that you ought to tell us what the Canadian experience is. Let me put it very simply: What has become of the people to whom you started giv ing aluminum ten years ago? Are they alive? Are they dead? What did they die of, if they did die? What is their physical condition at the present time?"
This afternoon 1 understand there is going to be a general discussion, with no holds barred, and it seemed to me I saw some of the gentlemen out in the hallway sort of sharpening up their razors. So, I hope you have a grand meeting this afternoon.
I think the Lead Industries Associa tion has done itself proud, and I think Mr. Manfred Bowditch has done a very good job.
Ch a ir ma n Bo w d it c h : We will re sume in the other room in five or ten minutes.
DU P050314480
TUESDAY AFTERNOON SESSION
NOVEMBER 16, 1948
Ch a ir ma n Bo w d x t c h : I think we might as well get started on our round table. I can assume that the first subject we should go back to is the stippled cell - urine discussion of yesterday,
which did not seem to have been ex hausted by the time we had to leave it for other matters. Is there anyone who would like to continue the discussion on this subject?
ROUND TABLE DISCUSSION
m
mft
Dr . Al b e r t S. Gr a y [Director, Bu reau of Industrial Hygiene, Connecticut Department of Health, Hartford, Conn.]: I just want to ask a question. We were using stipple cell counts some years ago, and then Carey McCord and the U. S. Public Health Service persuaded us to use the basophilic aggregation test. We are doing that, and it seems satisfactory, and I am not going back to the stipple cell counting unless a good reason is provided.
I would like to know somebody who is doing either or both of them, and if there is anyone here who thinks the stipple cell count is very much better than the basophilic count, I would like to know about it, because, if there seems to be a good reason to do it, we will go back to it. At the present time in all the industries in Connecticut which have any real lead exposure, part of the con trol that we require of them is certain medical control, part of which is a cell count. They can use stipple cells, if they want to, but we recommend the other.
I would like to get some opinions on that matter. At the present time we are running the basophilic cell counts, urine, lead in urine and porphyrin. Examina tion for porphyrin seems to be getting
quite popular now. We have only been doing it for a month. We are trying to
find out if we can get any correlation
between the porphyrin content and the basophilic aggregation and the lead in urine.
I believe, as these gentlemen said, the thing to do is to see the process, of course, and to see the individual.
Dr . Wil l ia m G. Wo o d [National Lead Co., St. Louis, Mo.]: Concerning the basophilic aggregation, from our observation over many years at the St. Louis Lead and Oil Works, we have concluded the basophilic aggregation test of McCord has proven not only of diagnostic but prognostic value.
We believe it to be a criterion show ing reaction to degeneration as well as denoting the degree of regeneration. I do not know how many of you agree with me on that, but we have found after about eleven years, since we have been using both the basophilic aggre gation and the stipple count, that a sig nificant rise in the basophilic aggrega tion indicates an increase in the forma tion of new cells, although some basophilic degeneration of old cells is included in this count.
When we see a patient showing a low hemoglobin and red count with positive history of lead exposure, coupled with an increase in his stipple count, and if his basophilic aggregation increases, we feel, and our experience has taught us that we have adequate reason to feel
125
DUP050314481
126 DISCUSSION
assured, that he is reacting physiologi
cally. especially if he is under treatment.
Another thing that I would like to
say is concerning the stipple count. I
would like to make an appeal for stand
ardization in their enumeration. Nor
mally, you know, we have anywhere
from 15 to 60 oiymore stipples, or socalled basophils per hundred thousand
red cells in the circulating human blood
at all times. Aside from our views as
to its importance in diagnosis and
pathology, I make this appeal, inasmuch
as we find in the literature, case reports
and records of divergence of opinion as
to the manner of enumerating stippled
cells.
.
We feel that, for expediency at least,
we should come to an agreement in this
matter.
As regards the number per field, I did
that for many years but found out, I
believed, we were in error to a certain
extent when we expected to establish
the number of stipples in the circulating
blood, while examining a few or even 50
fields, and noting the number per field.
I felt that we ought to consider the
fact that some fields contain more blood
than others and, therefore, more stip
ples, though admitting the fact that the
film should contain, say, from about 150
to 200 red blood cells per field. Fre
quently we see reports, [and to me it is
rather amusing] such as rare, few, oc
casional, many, so many per field, de
creasing, increasing, 1, 2 or 3-|-, Class
A, B or C, or one or more percent.
These counts, I contend, are more or
less confusing, inexact and misleading,
and I think we should be as explicit in
the stipple count as we are with our
other tests which, by common usage and
with more or less exactness we have
learned to understand are recognized as
standards. On this premise, I wouid like to ask
if it is not more practical to use the more
accurate and, furthermore, the simplest method, that one being used by most writers, of stating the number per hundred thousand or per million red cells. That has been uppermost in my mind for some time and I have been wondering why we do not standardize this thing. Of course, that is up to you gentlemen.
Mr . G. C. Wa l t e r s [National Lead Co., Chicago, 111.]: Could I say a word here? There is one reason why the stippled cell technique has not been standardized and that is because we have microscopic light fields and dark fields, and until we come to a common objective as to which is the best sort of a microscope to use for it, I doubt if we will get together on any one particular stain, or technique. There has been a lot said about the Wright stain, but I have never found it en tirely satisfactory for the light field work in stippling alone although it may be okay for other pathological blood work. It might be wonderful but we do not use the Wright stain in the light field. In the dark field it may be better than any other stain. I do not know, because we do not use the dark field.
Dr. Wilentz has used the dark field, and he might make some comment on it. I might say, while I am here that, as I stated yesterday, we compared the ag gregation count with the stipple count over a period of four years, running both. One time I tried to do both on the same slide, by fixing one half of the slide and not the other. It worked at times, and at other times it did not work. The only reason we gave it up was be cause of the staining qualities. The stain seemed to precipitate so by the end of tire week, on the same man who was not exposed at all, we would get different readings. For that reason, we finally gave up on the basophilic count, al though there may be some of you that
DU P050314482
ROUND TABLE
127
can use it to advantage, and, for those that can, I say "All to the good." I found men, absolutely non-exposed, who ran above IV2 percent which McCord allows, and even close to 2 percent, but that man did not show any stippling.
Dr . Wo o d : Very likely you have the difficulty with your staips. These stains, I understand, must be made up fresh.
Dr. L. E. Thompson of Washington University, does our blood work at the St. Louis plant and makes his stains up fresh each time. I think the secret of a lot of the troubles we have been having with the basophilic aggregation is the slain itself. I build a lot of faith on my basophilic aggregation. As 1 say, I al ways try to let the men know something about it, when I see the basophilic ag gregation going up. If the stipples are up and the hemoglobin and red count are down, I feel all right if the baso philic aggregation stays up, but let that drop and the others continue down, then I know I will have trouble.
Mr . Wa l t er s : I wondered if Dr. Sappington would say something.
Dr . C. O. Sa p p in g t o n [Industrial Medical Consultant, Chicago, 111.]: I want to ask a question. I would like to get Dr. Wilentz to talk about what he does with dark field with reference to either basophilic aggregation or stippled cells. I do not know anything about dark field at all with reference to these cells. I would like to know something about ihein.
Dr . Wil l ia m C. Wil e n t z [National Lead Co., Perth Amboy, N. J.]: I do not know of what value I can he about this particular subject. The scope that we use is a combination scope. It is two scopes in one. You cannot buy it; you have to put it together. It was developed by the Research Department of National Lead, and even all the various subsidi aries of National Lead do not have this scope available. For instance, I had to
have an extra one during the war, and
we found it almost impossible to get it
together. You have to buy a regular
microscope, and then you have to buy
special parts to it, to add to this. I can
not tell you what it is because I do not
know myself. There are only one or two
fellows in the whole country who can
put it together. One fellow left, and that
left one fellow, and the company cannot
afford to fire him. [Laughter]
Frankly, the truth of the matter is
that we have two scopes in one. We
use what you men all have, the ordinary
microscope, and then we have the dark
field addition. They double check; both
counts are checked on the same scope.
In other words, my technicians check
themselves by the stipple counts and by
the reticulocytes. They go hand in hand.
We have had men come down and ob
serve our set-up, which is a small set-up,
but where a lot of work is done. It is
tlie same old story, when they leave,
everybody wants that scope.
We had a man come down here two
weeks ago, the chief technician at the
Standard Oil Company at Bayway, New
Jersey. He no more than got back, in
fact he could not wait to get back to his
plant, he wanted a scope like that.
Let me put it this way, to show you
there is a difference: each man in his
own little bailiwick knows what he is
doing. That is the answer; it is as ob
vious as that. We happen to have this
particular scope. I do not say we know
anything more than anybody else. But
this dark field scope permits us to see
more than what you would like to see
sometimes.
Dr . Gr a y : That is the trouble. I see
more in the light field than I want to
see. [Laughter]
.
Dr . Wil e n t z : The point is this: We
have a very wonderful comparison. You
take, for instance, a man that we have.
We sent him to the hospital that very
j
DUP050314483
128 DISCUSSION
day. We had a count done on him in the morning at the plant. We sent him up to the hospital that very morning, and we had a count done in. the hospital immediately. Although we know counts are variable, the counts taken, for in stance, in our hospital, by their techni cians and the counts done by my tech nicians at the plant being very different, I am not concerned about that. We take the worst count and play ball on that count. We get the worst count by our scopes, in other words, .we are not kid ding ourselves because we can't afford to.
Mr . Wa l t er s : Our experience has been the same.
Dr . Sa p p in g t o n : You mean you get more in the dark field than the light field, a higher count?
Dr . Wil e n t z : Sure. Dr . Wo o d : There is no comparison with the dark field in the detection of the Treponema. Dr . Wil e n t z : It looks the same, but a different bug. Dr . Wo o d : Could we have a diagram drawn, so we could build a correspond ing scope ? Dr . Wil e n t z : Sure you could but not with my help. You have to be a magician, and I am not kidding. Dr . Wo o d : I believe I can get Dr. Thompson of Washington University lo do it. Dr . Wil e n t z : This is a scope devised by the research department, on its own-- it would be more proper to say, "put together." Dr . Wo o d : It isn't hidden. We can look it up and get all the facts. Dr . Wil e n t z : Well, I don't know. There is no trade mark. It is a special thing made up. You saw the scope that was in Life, wasn't it, about the doctor in Chicago looking up the sludge. He made it himself, that microscope. It is possible; these fellows can do anything.
but it is a very costly thing, by the way.
I think the ordinary microscope costs $300 today.
Mr . Wa l t e r s : Three to five hundred
dollars.
Dr . Wil en t z : I think, when you get
through with the scope I am talking
about, it represents about $800. I think
that is approximately what it is. But
that is not going to solve your problem.
It is still prophylaxis.
Dr . Go r d o n C. Ha r r o l d [Detroit,
Mich.]: I wish we had the same situa
tion of a man who cannot get fired.
Since everyone cannot have that, and
we do not have it, I would like to give
you some of our struggles with some
thing that everybody can have.
What we are looking for is something
that the physician can have in his office,
and maybe in ten minutes make up his
mind. I do not say it is the whole an
swer; it is part of it, and, again, we are
not making all-inclusive statements. It is
something that needs a lot of work.
I was talking to Dr. Mayers about
coproporphyrins the other day, and she
has had people from abroad who have
been determining porphyrins in urine.
Dr. Gray was talking about it today. It
is in the air. I think that it is timely.
It is something that we all should look
at very carefully. It may produce an an
swer that all of us have needed; an
answer to damage to the organism, and
not to the transport of lead in the blood
stream.
I mentioned the other day, in a par
tial answer, something that probably was
not any answer. This complete article is
going to appear, through the kindness of
Dr. Sappington, in Industrial Medicine
here in December, 1948. Since it is for
malized, it would, perhaps, be better for
me to read it as it will appear. It will
not appear as having been given at this
meeting.
.
Do not get me wrong on certain state-
DUP050314484
URINARY PORPHYRINS
129
merits. Dr. Meek and I talked about por phyrins in 1937 and 1938. We did not have enough to go on then, and, more than that, we received some initial dis couragement from friends of ours who did not think it was quite the thing.
It so happened that I have a friend who is probably the best man in chlorophyl in America, and chlorophyl, as you know, is only differentiated from hemo globin in the sense that you have a mag nesium ion or atom in place of the iron
atom. Don't ask me to draw the struc ture for chlorophyl; that is tough busi ness; I guess it can he done; I know it can be. Abroad they have been experi menting with porphyrins a long time
and 1 think they feel that it is worth a great deal. I am rather amazed it has not been timely enough in this country until recently. It seems that is one area where we have moved a little bit slower on than we should have. I will go on with this formalized paper.
URINARY PORPHYRINS IN LEAD POISONING
Py GORDON G. HARROLD, Ph.D.
Consultant, Industrial Health, Hygiene and Safety Service, Detroit, Mich.
Recently de Langen and ten Berg1 re ported on a simple semi-quantitative method for determining increased uri nary porphyrins in lead poisoning. Based upon a comparative examination of 87 persons with high lead intake in drink ing water and normal human controls taking pre-determined quantities of lead, these authors concluded their method of detecting abnormal amounts of urinary porphyrins was a more reliable early indication of lead poisoning than basophile granulation of erythrocytes.
Salomon and Cowgill" have investi gated urinary porphyrins in lead-poi soned dogs and have concluded that dogs excrete increased quantities of uri nary porphyrins in lead poisoning as does man, but porphyrinuria in dogs is a late, rather than early manifestation. Incidentally, you get a different por phyrin in dogs, evidently, copropor phyrins that may be I and II and the coproporphyrin III. The research work is just coming up to date. That is one of our difficulties with this whole busi ness. An editorial in the Journal of the American Medical Association3 recently
called attention to this interesting sub ject. It included a review of the work of Fischer et al who were responsible for most of our present knowledge of the structure and chemical relationships of the porphyrins. Fischer won the No bel Prize in 1930 for his work in demon strating various porphyrin isomers; his investigations were terminated by death in 1945. Also mentioned is the work of Watson4 and his group who have estab lished that 100 micrograms of urinary coproporphyrin per day is the upper limit of normal, about 80% of which is
the Type I isomer and about 20% is coproporphyrin III. The amounts of coproporphyrin vary in different patho logic states as does the ratio of the two isomers. Particularly in lead poison ing, coproporphyrin III in the urine is greatly increased up to 8 mg. per day.
The editorial previously mentioned3 cites Lhe theory advanced by Rimington6 to account for increased coproporphyrin III in the urine in lead poisoning. Rimington's theory is that the normal com bination of protoporphyrin with iron to form hemoglobin may be "blocked" by
130 HARROLD
lead; the protoporphyrin which is un though it be much higher than the upper
used is converted to coproporphyrin III limit of normal, it merely indicates ab
and excreted in the urine.
normal lead absorption, unless other
Rimington's theory gained support findings in a given case enable one to
when Vigliani and Waldenstrom (re make a clinical diagnosis of lead poi
ported by Kench8) reported finding an soning."
increase in blood protoporphyrin in lead
Because quantitative analyses of urine
poisoning and Vannotti and Imholz7 for lead are time-consuming and require
found' an increase in non-hemoglobin specific, and for some methods, expen
iron in lead poisoning.
sive equipment and qualified personnel,
However, Kench et als do not accept attention has been focused on the need
the Rimington theory because they could for simple tests which will give an early
not correlate quantitatively the copro indication of dangerous lead absorption
porphyrin III excretion in lead poison or lead poisoning. The need is for sim
ing with hemoglobin metabolism. They ple, inexpensive tests which can be per
prefer the theory that lead in the blood formed in plants or physicians' offices
stream is absorbed on the lipoid-protein by the industrial hygiene field worker
film of the erythrocyte, and early de or the physician.
struction of red cells in the peripheral
Quantitative enumeration of baso
circulation is, or gives rise to, stimula philic stippled erythrocytes has been
tion of bone marrow. When consider found to he a fairly laborious and time
able lead is present in hone marrow, the consuming technique and one that is
production of protoporphyrin for hemo not entirely specific, nor is the correla
globin formation is inhibited. Thus, tion with clinical state and other tests
Kench's group view decreased hemo satisfactory. I think the fact that we
globin in lead poisoning as due to de talk about it and have to talk about it
creased formation of protoporphyrin so much indicates the uncertain state of
rather than lack of its utilization.
affairs. The basophilic aggregation test
In most of the reference material of McCord,10 while no more specific, has
given to this point, there is no attempt proved to be a valuable refinement; it
to distinguish between lead absorption is relatively simple and saves time. This
and lead poisoning;0 this distinction is test is particularly suitable for rapid
i important in any consideration of uri large scale survey work. Positive results
nary lead content. Adequate urinary in individual cases can he valuable cor
lead determination procedures, having a roborative evidence. Good correlation
sensitivity in the order of one micro between the basophilic aggregation test
gram per liter, as used in the work re and urinary lead excretion has been
ported herein,10 will indicate lead excre demonstrated10 in the case of certain
tion specifically and provides a basis for lead salts soluble in human pleural fluid
comparison with the accepted normal and blood serum. It does not correlate,
range of urinary lead excretion in unex as we have indicated,10 in "old" cases
posed persons.8'10'11 It is believed that of lead poisoning. We have had a num
correlation has been established between ber of cases that were given to us. We
the lead content of 24-hour collections checked up on it and went through it.
of urine and samples consisting of single I am sorry Dr. Fredrick has evidently
voidings.10,12 However, the amount of had to make a train. I had hoped he
urinary lead excreted per liter or per would discuss that because he has a lot
day is just that and no more; even of additional information.
DUP050314486
URINARY PORPHYRINS
131
The urinary porphyrins have been ples as were used to determine the por
given considerable attention with refer phyrins were used in Column 2 but two
ence to lead poisoning. The hope is ex drops of 3% hydrogen peroxide were
pressed that as our knowledge of por phyrin metabolism increases, a simple test may be evolved which will give an early indication of lead absorption and/or lead poisoning.
The following report does not reveal
added. The peroxide provides the same basic information under ultraviolet light as the samples without it but the inten sity appears slightly increased and equal in all instances so that doubtful cases may be determined. It has been noted
such a test, but it is hoped that it will that some samples which gave a faint
aid in stimulating interest in this ap doubtful appearance of red phosphores
proach to the problem.
cence did not give this appearance with the H202. All samples in which the red
EXPERIMENTAL
or light pink fluorescence appeared with out question without the H,02 showed
Single voidings of urine were ob the same, abeit slightly intensified color
tained from 66 workers exposed to lead with the H202.
fumes. The lead content was determined
We, therefore, have relied in our
on a portion of each sample.10 The semi- evaluation on the results revealed by the
quantitative urinary porphyrin test of method modified by H202.
de Langen and ten Berg1 wes performed
It will be noted in Table I that 31 of
on another portion as follows:
66 samples gave some degree of red
To 20 cc. of urine, add 2 cc. glacial fluorescence and could be called posi
acetic acid and 2 cc. ether and shake tive. It can also be noted that there is,
briefly [I am sorry this paper does apparently, no great correlation between
not point out the fact that we added the fluorescence phenomena in the case
another cc. of ether because of the of the positive findings with the urinary
20 cc. of urine absorbing a certain lead content. That is probably an over
proportion of ether and a certain simplification. There may be consider
amount going off in gas.j; the test able correlation.
tube is then examined under ultra
This ratio of 31 positives out of 66
violet light. You do have a certain lead-exposed workers may be compared
millimicron range here that you prob with the work of Franke and Litzner
ably should hit, but it works under a cited by Watson4 who found that 17 out
general ultraviolet light. We tried it of 43 lead-exposed workers gave urine
out with a toy, and it worked beauti samples containing over 500 gamma co
fully; just as well as it did with an proporphyrin III per liter, the range
. expensive instrument. The normal being 120 to 1,810 gamma per liter. The
I urine subjected to this procedure will normal range of coproporphyrin III for
reveal a light blue to green fluores unexposed persons was reported as 30 to
cence in the ether layer. Urine con 70 gamma per liter of urine.
taining large amounts of copropor
There are some variations in this work
phyrin III will exhibit a rose to deep that, have been reported by various in
red fluorescence in the ether layer.
vestigators. It is not conclusive, but I
This data is shown in Table I, to think the indications are it will be a tool
gether with the further data provided by that will be available which, when
a modification previously used in other worked up, will be infinitely more valu
work with porphyrins. The same sam able to us than basophilic aggregation
.;jp'
DU P050314487
132 HARROLD
Table I
Porphyrin Evaluation
Porphyrin Evaluation
modified by HiOs
Urinary Excretion of Pb in mg. per liter
Porphyrin Evaluation
Porphyrin Evaluation modified
by HzO?
U rinary
Excretion of Pb in mg.
per liter
LR.............. . . . VLR . . . . . . 0.36
BG . . . . . . . BG . . ,. . . . 0.38
B .............. . . . B . . . . . . . 0.26
RR.............. . . . RR . .
. 0 44
RR plus . . . . . RR . . . . . . 0.56
R .............. . . . R . . . . . . . 0.60
BG.............. . . . BG . . .. . . . 0.12
B ..............
. . . . 0.30
B .............. . . . B
RR.............. RRR .... B?.............. RR.............. R .............. RR..............
B? ....
BG..............
R?..............
BG . . . .
R .............. R?................. R?..............
BG . . .
LR..............
B ...
RR.............. RRR..............
.... ... .... .... ". . . ... ... ... ... ... ... ... ... .. . ... ... . .. ... ... ...
0.42 0.32 0.42 0.20 0.12 0.24 0.26 0.46 0.34 0.32 0.16 0.86 0.12 0.10 0.16 0.02 0.18 0.22 0.14
R?.............. . . . BG . . ... . . B .............. . . . B . . . . . .
BG.............. . . . BG . . . . . , BG.............. . . . BG . . ., . . .
B .............. . . . B . . . ...
R................... . . . R . . . . . .
R?.............. . . . R . . . . . .
BG.............. . . . BG . . . . . .
R?.............. . . . BG . . . . . .
B?.............. . . . VLR . . . . . .
BG.............. . . . BG . . . . . .
BG.............. . . . LR . . . . . . R ..............
R .............. . . . RR . . . . . .
BG.................. . . BG
BG.................. . . BG R .............. . . . R
... ... ..... ... ...
RRR .... . . . RRR . . . . .
R .............. . . . RR . . . . . .
RR.................. . . RR . . . . . .
RRR............. . . . RRR . . . . .
B ................. . . . B B ................. . . B
... . .. ... ...
B?................. . . R . . . . . .
B .............. . . B . . . . . .
B ................. . . B . . . . . .
B ................. . . B . . . . . .
0.10 0.20 0.14 0.24 0.18 0.46 0.30 0.10 0.28 0.32 0.44 0.44
0.50 0.36 0.81 0.35 0.53 0.40 0.51 0.61 0.15 0.20 0.25 0.24 0.37 0.23
BG.................
BG . . . .
. . BG
BG.................
.. . . :. . . .
...
0.22 0.26 0.14
B ................. . . B BG ..... . . . B BG................. . . B
.. .... .... .. ... ...
0.28 0.19 0.20
BG.................
LR . ..............
. . . 0.16 R ................. . . RR . . . . . . 0.52
. . . C.32 BG ...... . . B . . . . . . 0.31
RR ...... . . RR . . . . . .: 0.14 RR................. . . RR . . . . . . 0.22
Symbols: B: Blue BG: Blue Green
VLR: Very Light Rose
LR: Light Rose R:Rose RR: Strong Red
RRR: Very Strong Red
Note: Some of the values marked "BG" actually had a strong yellow fluorescence but in view
of the fact that this phenomena was negative as regards the light rose colors, these few values were included as "BG's."
DUP050314488
w
It
ISPi;
WB-
11
jf
M: !
i.
URINARY PORPHYRINS
133
or stippling methods and, certainly, it will be an additional tool.
Watson1 reported normal copropor phyrin III in urine of unexposed indi viduals as ranging from 1.4 to 34.3 gamma per day. The results published by Kench3 are of a lower order; he re ported on 12 lead-exposed workers whose average urinary lead was 292 gamma per liter with a range of 182 to 436 gamma per liter; the average copro porphyrin III content of the urine was at the rate of 88 gamma per liter with a range of 16 to 343 gamma per liter. Kench did not demonstrate direct corre lation of urinary lead with copropor phyrin III.
Schein14 would indicate that 50 gamma would be the high upper limit for copro porphyrin III per liter of urine. The fluorescence phenomena is quite sensi tive and will appear below this range. Experimental data correlating fluores cence with coproporphyrin III is not available to us at the present time.
SUMMARY
The rapid evaluation of present or potential lead intoxication by means of the determination of porphyrins in urine is subject, as is stippling or basophilic aggregation to the influence of a num ber of other chemicals. However, it is not directly dependent on any blood discrasia and is much more likely to be indicative of lead intoxications which are not dependent on anemias. It, there fore, represents potentially a laboratory tool which can represent with much greater fidelity the various forms of lead intoxication than could stippling meth ods. Finally, it should be noted that we are relating a phenomena which may be much more indicative of damage than either the amounts of lead in blood oxurine which, at best, represent an indi cation of the transportation of lead in
some form or another throughout the
organism.
-
BIBLIOGRAPHY
' de Langen, C. D., and ten Berg, J. A. G., "Porphyrin in Urine as First Symptom of
Lead Poisoning," Acta Med, Scatidinav., 130, 37 (1948). (Abs.JM.M.A., 138, 244, 1948).
s Salomon, K., and Cowgill, G. R., "Porphy rinuria in Lead-Poisoned Dogs," J. lad. Hyg. & Tox. 30, 114 (1948).
3 Editorial, "The Significance of Urinary Co
proporphyrins," J.A.M.A., 136, 627 (1948).
* Watson, C. J., and Larson, E. A., "The Urinary Coproporphyrins in Health and Dis
ease," Physiol. Rev., 27, 478 (1947).
5 Rimington, C-, Compt. rend. d. trav. da lab. Carlsberg, serie chim., 22, 454 (1938).
"Vigliani, E. C-, and Waldenstrom, J.,
Deatsch. Arch. f. klin. med., 180, 182 (1937)
(As reported by Kench).
7 Vannotti, A., and Imholz, A., "Die Beziehon gen des Reticulumendothels Zum Umsatz des Nichthamoglobineisens," Z. ges. exp. Med. 106, 597 (1939).
3 Kench, ,T. E., Gillam, A. E., and Lane, R. E-, "Haemopoiesis in Lead Poisoning" Biochem. /., 36, 384 (1942).
" Occupational Lead Exposure and Lead Poisoning, American Public Health Associ ation Report of the Committee on Lead Poi soning of the Industrial Hygiene Section (1943).
10 Meek, S. F., Collins, G. R. and Harrold, G. C., "Correlation Coefficient Between Baso philic Aggregation Test and Lead in Urine," J. Ini. Hyg. & Tox., 22, 401 (1940).
,lKehoe, R. A., Thamann, F., and Cholak, J., "Normal Absorption and Excretion of Lead," J.A.M.A., 104, 90 (1935).
77 Barnes, E. C., "Possibilities of Control of Lead Exposure by Examining Less than 24
Hour Urine Samples," J. Ind. Hyg. & Tox., 21,
464 (1939).
13 McCord, C. P., Holden, F. R-, and John ston, J., "Basophilic Aggregation Test in the Lead Poisoning Epidemic of 1934-1935," Am. J. Pub. Health, 25, 1089 (1935).
14 Schein, U., "Zum Nachweis der Porphyrinuric bei Bleier Kraukungen" Arbcitsschultz, pp. 336-339 (1943) ; Chem. Zentr., 2, 46 (1944).
mm
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Ch a ir ma n Bo w d it c h : I might com ment on this very interesting discussion of Dr. Harrold's by saying that he showed me this paper two weeks ago or so, when I was here in Chicago, and I conceived the idea that it might be made the basis of a little symposium here this afternoon on the subject of porphyrins. I discussed it wifh Dr. Mayers and found that she was extremely interested. I discussed it by telephone with Dr. Aub in Boston, who suggested that I get in touch with Dr. Karl Dohriner at Me morial Hospital, which I did, and had a little session with him. He suggested that I get in touch with Dr. Watson at
the University of Minnesota. 1 tried the next morning to reach him at Minneapo lis and wound up by reaching him in Richmond, Virginia. He was extremely interested and enthusiastic, but found it impossible to be here because of an unbreakable prior engagement. Of course, the whole tiling was on very short notice, but, from my conversations with these individuals who are experts in the field, there is no question in my mind that there will be no diffi culty whatsoever in pursuing the matter further.
Dr. Mayers, would you care to com ment on the subject?
DISCUSSION
Dr . Ma y R. Ma y e r s [New York State Department of Labor, New York, N. Y.]: I do not feel as though I really know anything about it. I am greatly in terested but, beyond that, 1 do not know that I have anything to contribute at this stage.
Mr . G. C. Wa l t er s [National Lead Co., Chicago, 111.]: Could I ask Dr. Harrold what he used on his urine lead, in his talk yesterday, and how it compares in time and complexity with the por phyrin that you just talked about now? Have you compared the two?
Dr . Ha r r o l d : You mean you want me to tell you how fast we can do urinary leads, or how slow you can do these porphyrin tests? That is an inter esting topic.
We do have certain thoughts on that subject of what you can do, how fast and how many. You have certain choices with Cholak's spectrographic method. You can test up to 40 urine samples a day. I do not think you can do more than that, and with the polarograph and with a good man doing the work, you
can analyze, perhaps, 50 urine samples a day for lead content.
With the dithizone method we pub lished some time ago -- the method that we use -- we are stuck with it; with that method which was published back about 1937, 1938, or something of that sort -- we have been using it since 1935 or 1936 -- we cannot analyze more than 25 samples a day, and that takes a good man working a little overtime on his eight-hour shift. Even good men do not like to work more than eight hours. But this method you can probably complete in less than fifteen minutes, and all you need is a test tube and a strong right arm. I have tested over 100 samples in eight hours.
Dr . Gr a y [Director, Bureau of In dustrial Hygiene, Connecticut Depart ment of Health, Hartford, Conn.]: You don't need a very good technical man either, do you?
Dr . Ha r r o l d : No . Once you set up your chart, anybody who can read could do a pretty good job on the thing. That has some obvious merit. It may not be
1
3 8 A ii
I
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the final answer, but I think that it will add tremendously to our knowledge.
5ut I think we need to review the fact that, in our various laboratory artefacts -- I am not a physician, my partner is -- we determine laboratory artefacts, and that is all they are. Who was it said -- I believe it was Dr. Eagle -- a rabbit is a rabbit is a rabbit, and you cannot change that. In determining lead in urine, it is lead in urine, but as to whether it hurt anybody in getting there, I do not think we know a thing and that is what we want to know. I think the porphyrins will tell us whether somebody got hurt, when that lead was going through the organism.
I wanted to emphasize something that Warren Cook said. Determine lead in urines, and keep on using the method because it does provide a good yardstick on certain operations in the plant, when you are doing operational control and building your safeguard, so you will not have any sick people. While you are doing that, your lead in urines do help, and are an added factor in your engi neering control. In that sense, I think it is perhaps as important as it is in your diagnostic data. Does that answer your
question ? Mh . Wa l t er s : Very good. Dr . J. M. Le o n a r d [National Lead
Co., Chicago, 111.]: Do you use a Wood's filter?
Dr . Ha r r o l d : No. Dr. Watson, whom Manfred has men tioned here, is really, I think, the dean of all authorities in this country and has done sound, solid, back-breaking work, and he probably knows more about it than anybody in this country and perhaps as much as the three or four or five outstanding experts in vari ous other countries. You do not have to use a Wood's filter. It is true that you get an ideal band at 401 nra.'s, and then there is
another band at 357, but for the copro porphyria 111, it is about 401. It may not be to your advantage to want to complicate this kind of thing. If you could set up a sound basis to do the test in the office on a basis of a gradation of six different degrees, from where there is "nothing," or "up to something," or "very strong," it may be that that is as far as you want to take it.
So far, all the work that has been done, in trying to make it extremely ac curate, on a fully quantitative basis, has led to quite a lot of variations in the amounts of coproporphyrin III that are determined by various investigators. There is another point. The fluorescent phenomenon is more sensitive than many others, and you have difficulty in forming test compounds, which is just like that of dithizone utilization. It may be beLter not to do those things. You certainly do not have to get the kind of data we were putting together.
I presume, Dr. Gray, you have been doing something like that.
Dr . Gr a y : Exactly. Dr . Ha r r o l d : Dr. Fredrick and I see each other at meetings, and he has told me some of the things he has tried. I even see Bill Witheridge at meetings. Dr. Fredrick was telling me about what he has done. He has taken some samples which he can read in the daylight, with out the fluorescent phenomenon. They start getting red in the ether layer. I suspect that would go high in our sixdegree range. The ones we found ex tremely strong were in that category. Dr . Le o n a r d : Does your entire ether
layer fluoresce? Dr . Ha r r o l d : The whole ether layer
will fluoresce, and the other material below that will fluoresce. Urine will fluoresce a yellowish or greenish type of color. The phenomenon of that light yellow means something. I do not know what it means. Whether it is bismuth.
Mi
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and we have a tip-off, as we do in the dithizone action or some other organic material is present, is uncertain. It is an interesting sidelight.
Dr . Jo h n E. Sil s o n [New York State Department of Labor, New York, N. Y.] : Aren't coproporphyrins stable, so you could make up standards containing measured quantities and use them for comparisons?
Dr . Ha r r o l d : Yo u can, but I have not done it. It is a tough job. What you do is to break down your hematin, and hematin, broken down, goes into por phyrins and you get a certain amount of coproporphyrin III and copropor phyrin I, and at least eight other cop roporphyrins. You form your methyl esters then. After you have done the separation technique, you take the methyl esters back, and you can get your coproporphyrin III. It is not an easy job but it can be done.
The original work was done the hard way, by taking hundreds of gallons of urine, and some people took blood, and various methods of getting breakdowns, and going at it in a pioneer way. That part is established. It is now a matter of applying some of the things we know, and pushing ahead. In my opinion, the step is short. I do not think we have to go loo far before we have something fairly decent, and the next year should produce a reasonable answer.
Mr . Wa l t e r s : Will your paper be available?
Dr . IIa r r o l d : It will be published December 15.
Dr . Sa p p in g t o n : About that time, in
Industrial Medicine. Ch a ir ma n Bo w d it c h : Is there further
discussion of this subject of die porphy rins?
Dr . Le o n a r d : I would like to ask a question. Has anyone used the spectro graph in the determination of lead in urine. Is it reliable, and can wc use it?
Ch a ir ma n Bo w d it c h : It is not used widely, 1 believe, and my knowledge of its use is very limited.
Dr . Le o n ar d : We have used it on one sample. I took just a single specimen from one of our boys who has persistent ly shown a fairly high stipple cell count. Our man over at the plant took a drop of this urine, dried it out and sparked it under the spectrograph, and he got a very beautiful red ink, and he just estimated the number of gammas of lead per liter that that urine would be. It is simple. It certainly is a simple thing to do. It only takes a few minutes. I wonder why there hasn't been some thing more done about it. I would like to see some work done on it, and maybe it could help clarify all this controversy about quantities, amounts and all of that.
Dr . D. J. La u e r [Kettering Labora tory, University of Cincinnati, Cincin nati, Ohio]: I just wrant to say that Cholak of the Kettering Laboratory has been using the spectrograph for the determination of lead and other trace metals in many types of biological ma terial, including samples of urine of large and small volume. He has been using a spectrographic method as a check method on the dithozone method for years and has published extensively on it. Certain other investigators are using it, too. The methods are satisfac tory and are available to those who have proper equipment and adequate technical training.
Ch a ir ma n Bo w d it c i-i : I might add this comment to the question that was raised a little while ago with regard to the standardization of stippled cell count ing in connection with the work of a subcommittee of the Z-37 Committee of the American Standards Association.
I wrote to the other members of this subconmiitee last June, suggesting that two questions be taken up by the main committee, one being that of establish-
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ing separate atmospheric standards for the various compounds, or some of the various compounds of lead on the basis of their known greater or less toxicity, and the second one being the question of establishing standards for stippled cell counting.
The replies varied very greatly. I had them mimeographed aftd sent them out, in turn, to some 20 or more authorities throughout the country, asking for their views, and those, in turn, came back. I should say I had somewhere between 25 and 30 replies in all. There was no uni form support for the idea of trying to work out standards for stippled cell counting, and I got all kinds of replies on the question of standards for the various lead compounds, which boiled down to two main schools of thought.
One was to the effect that we should let well enough alone, even admitting that there was a tremendous variation in tox icity, and that the 1% mg- per 10 M3 was so well established that we might as well hang onto it and let it go at that, leaving any questions of discrepancies in toxicity to the intelligence of the indi vidual industrial hygienist.
The other school believed that we definitely should do what I proposed, and that we should do it as immediately as possible. They were equally divided. There was also a sub-school that felt that we should set up these separate standards, but only after further and careful research.
So that is where the matter rests. I used these opinions as a basis for my part in a panel discussion at the A.P.H.A. in Boston last week, and the comment I got there again indicated a quite sharp division of thought on the subject.
I mention this only because lead is
interesting to all of us here and, like the woman convinced against her will, 1 am still of the opinion that it is illogical to use the same standard for galena that we do for lead oxide.
I believe that Dr. Mayers was of the school that thinks we should let well enough alone. Would you care to com ment on this, Dr. Mayers?
Dr . Ma y e r s : 1 think it is a very in teresting subject. My principal reason for wanting to let well enough alone, is that I feel you are dealing not only with differences in chemical formula: but with differences in physical proper ties, and operational factors as well. So, you have several variables, and we do not know very much about any of them. We do not even know too much about differences in permissible standards on die basis of the purely chemical for mulae alone.
So I feel that, to be wandering out into this great unknown, would not be very helpful. Why not drerefore just leave it as it is until we get more in formation? Perhaps some time in the future it might be a good idea to do something. But we are dealing with at least dnee variables about which we know very little; and any one of which can swing the picture, outbalancing the other two. Even operational factors are
uncertain in terms of quantities used
and the many and varied conditions of
exposure. I believe we would be just wandering into a field where we would
really have very little scientific data to guide us.
Ch a ir ma n Bo w d it c h : Are there any
further comments on this subject? If not, I will declare the Conference at an end. Thank you very much.
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