Document G5grOjr7LjMEeLk8pOrjn81vm

December 19* 1938 Mr. F* E, Harfc Anaconda Wire and Cable Company Marion* Indiana Dear Mr* Hart*- I have no doubt you remember the suggestions which I made at the time of my visit to your plant. However some of our observations in dicated that there might be some factors in the lead absorption of your workmen which were not fully accounted for by my observations. Accordingly I have thought it best to make a brief report* giving you the benefit of all the data and information which we obtained and making such certain recommendations to you for the avoidance of further difficulties. I have just heard from Mr. Shaner concerning the outcome of the suit against your company. I am not surprised at this result and, as a matter of fact* I think you are rather fortunate that the vereict was not larger. On the other hand I wish to confirm my belief, without which I would not have testified in this case* that this man did not have lead poisoning and that it was not a factor in his present disability. Of course he may have had some rather mild symptoms of plumbism at the time of his initial illness* but I doubt this* and there was no evidence in the record* so far as I saw* which justified one in making a diagnosis of lead poisoning. On the other hand* there was no proof that he did not have lead poisoning. This was the weakness in your case* since you were confronted with the testimony of at least two local doctors who believed that the symptoms were feferrible to lead absorption. This 13 the problem which all employers of w orkmen in the lead trades have to he able to meet. The diagnosis of lead poisoning is regularly made on the history of exposure$ That Is to say* the occupational history of the employee that Indicates that he is engaged In work which involves some contact with lead-containing materials. The average doctor does not make any attempt to evaluate the magnitude of the exposure and he tends to ascribe any existing illness to the effects of lead absorption* If he is not straightened out at that time by a thorough study of the patient* which demonstrates the facts one way or the other, he will thereafter hold to the conviction that his diagnosis was correct. It is, therefore, incumbent upon the employer to obtain medical assistance and advice which is more competent than that of the general practitioner of medicine. It is for this reason that I have made reference in the attached report to a means by which the facts can be obtained in doubtful cases of illness among employees* I think the time is coming and, in fact, not far away when employers in the hazardous trades will be compelled to exercise the utmost precautions in the avoidance of exposure. Despite this fact, I think there will be an increasing necessity for the utmost precision in the medical supervision of workmen In industry, I trust you will find the report which I send herewith.of some interest and value. Very truly yours. RAKjis Robert A.' Kehoe, MYd . i KE" 0020967 MAGNITUDE OP LEAD EXPOSURE It? MARION, INDIANA PLANT OF ANACONDA WIRE AND CABLE COMPANY Air samples were taken In the Immediate vicinity of a melting pot in which scrap lead from cables was being melted* Detailed observations were made over a period of an hour and a half In order to note the conditions which were most favorable for the distribution of particulate lead compounds In the atmos phere* It so happened that the end of one ohlft and the beginning of another came during these observations* This period involved the removal of dross from the melting pot, an operation which occurs once per day, and which Involves much greater dissemination of dust than that associated with any other procedure* Air samples were taken from several points about the pot, at the height of the operator*s face, during the period of normal operation. These samples were composited into Sample wl* Another series of samples, similarly combined as Sample G2 were obtained during the filling of the pot and during the removal of the dross* The analysis of these samples yielded the following results*- Sample #1 .21,144-0*0 ml* contained 0*002 rag/Pb equivalent to 0*09 per cu# meter* Sample **2 21,635*0 ml* contained 0*006 mg* Pb equivalent to 0*28 mg* per cu. meter* The values for particulate lead in atmosphere are usually expressed In terns of 10 cubic meters of air, and on this basis It is currently accepted that values in excess of 5 HE 0020968 N 24436.01 -2 at'illgrsBss per 10 cubic Enters are unsafe# Some workers give 3llghfcly loaer values* in aota instances m low ns 1*5 milligrams per 10 cubic motors* *Tho evidence* however* la very good In Indicating that basic exposures as low aa that involved in bre thing air containing 2 1" llgrema of lead per 10 cubic meters* are sub stantially cafe for all workera regardless of susceptibility factors* On thia baala of ccaparison the values observed in the vicinity of the pot ay be regarded m Indicative of safety* in that the basic lead concentration has appeared to be in the neighborhood of 1 milligram per 10 cubic Enters* chile the brief periodic exposure* during dressing and shoveling Is of the order of 2*5 to 3*0 milligrams per 10 cubic meters# Ey experience is Industry loads o to believe that this degree of exposure does not Induce sufficient load absorption to cause load poisoning# This conclusion la fully verified by the results obtained in the semination of 2 employees whose work has involved dally exposure to such lead as 1 regularly distributed into the atmos phere around the pot* neither of the two workmen showed say clinical evidence of occupational lead absorption* neither had a lead line* despite the presence of conditions in the mouth (pyorrhoea) which are favorable to the development of lead deposits in the gum tissue* neither of them showed any blood changes (anemia or stippling) suggestive of load absorption# neither of the had abnormal quantities of lead In their blood end urine# had 0#9l* ffig# Pb per liter of urine* and 0*05 mg# Pb per 100 grams of whole blood* while0*03 mg* Fb per liter of urine and G#Q55 ag* Pb per 130 grams of whole blood# These are quite within the limits of values found in perfectly normal persona with no occupational exposure to lead compounds# K E" 0020969 X conelad# therefore# from the .cabins tl on-of - these data# that the occupational conditions studied at this time are not such m to entail tho risk of lead poisoning in workmen* It is also my pinion that the conditions described m in existence at the tin of the plaintifffs employment* while probably involving somechat greater exposure than that ahlete occurs at present# were not sufficiently different in type or magnitude to justify an opinion that lead poisoning would have resulted fro the exposure# Good clinical evidence would be required# therefore# to convince me that the plaintiff had lead poisoning at the tire It as claimed that he- had# By good clinical evidence I mean that characteristic symptoms# associated with lead line of the gums# perhaps# and certainly with excessive numbers of ''stippled1* red blood corpuscles# should have been present* rfha presence of ab normal quentities of load in the urine or blood or in both at that tl`0# would have been convincing# chile- the lack of ouch evidence is a serious fault in the plaintiff *s claim* Beturnine to the subject of "stippled" erythrocytes (red blood corpuscles) it is necessary to demonstrate the presence of abnormal numbers before significance can be attached to the phenomenon * "Stippled" erythro cytes occur in the blood of normal persons up to ton or more per fifty microscopic fields* and they are found la increased numbers In a wide variety of conditions which have nothing whatever to do with lead absorption* Their presence# without reference to numbers# or without knowledge of other concomitant changes in the blood# Is nholly without diagnostic significance* Signed tf. 'S 0020970 Hebert A. KKBCE REPORT AND RKCC*8fiSt>ATI< . <1 ON CERTAIN C0NDITK N8 OBSERVED ANACONDA SIRE AND CABLE CO 2 A NY at MARion, INDIANA* Air samples ere taken In the Immediate vicinity of a melting pot In which scrap lead from cables as being melted. Detailed observations ere made over a period of an hour and a half In order to note the conditions which or most favorable for the distribution of particulate lead compounds In the atmos* phero* It so happened that the end of one shift and the beginning of another came during these observations* This period involved the removal of dross from the melting pot* an operation which occurs several times in each shift* and which Involves much greater dissemination of dust than that associated with any other procedure* Air samples ere taken from several points about the pot* at the height of the operators face* during the period of normal operation* These samples nor composited into Sample ul. Another series of samples* similarly combined as Sampled ere obtained during the filling of the pot and during the removal of the dross* The analysis of these samples yielded the following results* Sample ul 21*144.0*0 ml* contained 0*002 mft/Pb equivalent to 0*09 mg* per cu* meter. Sample 2 21*635*0 ml* contained 0*006 mg* Pb equivalent to 0*28 mg* per ou* meter* The values for particulate lead in atmosphere are usually expressed In terms of 10 cubic meters of air* and on this basis it is currently aoeepted that values In excess of 5 HE 0020971 N 24436.02 2 milligrama per 10 cubic meters are unsafe* Some workers give slightly lower values* in some instances as low as 1*5 milligrams per 10 cubic meters* The evidence* however* is very good in indicating that basic exposures as low as that involved in breathing air containing 2 milligrams of lead per IQ cubic meters* are sub* stanfcially safe for all workers regardless of susceptibility factors* On this basis of comparison the values observed in the vicinity of the pot may be regarded as indicative of a reasonable safety, in that the basic lead concentration has appeared to be in the neighborhood of 1 milligram per 10 cubic meters* while the brief periodic exposure* during dressing and shoveling la of the order of 2*5 to 5*0 milligrams per 10 cubic meters* My experience in industry leads me to believe that this degree of exposure does not induce sufficient lead absorption to cause lead poisoning* This conclusion is verified by the results obtained in the examination of 2 employees whose work has Involved daily exposure to such lead as is regularly distributed into the atmos* phere around the pot* Neither of the two workmen showed any clinical evidence of occupational lead absorption. Neither had a lead line, despite the presence of conditions in the mouth (pyorrhoea) which are favorable to the development of lead deposits in the gum tissue* Neither of them showed any blood changes (anemia or stippling) suggestive of lead absorption* Neither of them had abnormal quantities of lead in their blood and urine* had O.OU mg* Pb per liter of urine, and 0.03 g* Pb per 100 grams of whole blood* while 0*03 mg* Pb per liter of urine and 0*035 mg. Pb per 100 grams of whole blood. These are quite within the limits of \slues fouhd in normal persons with no occupational exposure to load compounds. K 002097a 3 Certain additional observations ere mad in the plant and on the two workmen which nor not referred to in the preceding paragraphs* Samples of the feces of the two men ere obtained on the morning after a day of normal work. Vie have found that such samples give a good Indication of the magnitude of the lead exposure. Unfortunately one of the fcno samples was too small to be useful but the other contained l?ijj6 ragra* lead, a quantity which is suggestive although Inconclusive evidence of significant lead exposure* A sample of dust was taken from the top of an electric switch or fuse box situated above a drinking fountain abcr* 10 feet from the melting pot* This dust was seen to contain small bfight globules of metallic lead, which evidently had been dis charged from the molting pot* The analysis of this dust demon strated the presence in It of 23*7^ of lead* There was a con siderable quantity of dust at this point, and it Is believed that the analysis indicates the dessemination into the air of un necessary quantities of metallic lead in finely divided fora* Just what operation in the plant Is responsible for this situation la not apparent, but the matter should be investigated# On the basis of the combined observations, it is recommended that certain changes be mad in >the equipment and operating procedures. (1) . The fan which blows across the melting pot from the rear of the operator should be eliminated In order to avoid the distribution of dust into the air. (2) The melting pot could with probable advantage be enclosed 002097$$. on three aides In much the some fashion as a ehonlcal fuse hood, (3) An extension of the ventilating duct should be extended to the area immediately overlying the pigging molds* (h) The dross from the pot should be removed directly into a receptacle which la equipped with a tight-fitting top. Instead of making use of an intermediate tray which subsequently must be emptied into a large collecting receptacle* ($)* Other sources of dust and fume should be sought out by means of periodic critical observation of all working operations. When such sources are noted, they should be corrected* (6), .orkmen on this job should be supplied 1th work clones, and with double lockers* They should remove their clothing put it In the clean locker and change to work clothes (kept in the other locker), At the end of the shift, they should reverse the process, bathing before resuming their clean clothing, (7) Quite In addition to the advantages of greater safety to the workmen, experience has shorn! that pre-employment and periodic examination of workmen in hazardous trades, or in trades which are generally aseiaaed to be hazardous, provides a considerable security to the employer against mistaken or fraudulent claims of occupational Injury or illness* Such examinations should be carried out with precision* If done properly they will prove useful for the recognition of hazardous exposure* The advantages of such In formation are considerable In view of the frequency olfch which operating changes occur In manufacturing plants* When vague or uncertain types of Illness appear among workmen, it is advisable, from every point of view, to make complete ollnical studies and to arrive at diagnoses which can. If necessary. be substantiated in court. The typo of nodical service which will accomplish this purpose, will deserve the confidence of workmen and will pre%mnt difficulties like the cases recently at issue, while at the sea time, it will inform plant management as to the status of such occupational hazards as arise from the operation of a plant. Such medical supervision is recommended, at least, in the case of men engaged in work which involves potential spoeure to toxic materials# Any assistance or advice whleh will be instrumental in bringing about such an hygienic program will gladly be given# Signed? Sireoior ~..'..... t,r Kettering laboratory of Applied Physiology University of Cincinnati 0020975