Document zdRJ1zRK8B07BV2nNzLaJZgj3

Oct ober 11, 19I4. I. Mr. R. L. Forney, Director, Industrial Division, National Safety Council, 20 North Wacker Drive, Chicago, Illinois, . 1 Dear Mr. Forney: I an. returning to you herewith the second and third drafts of pamphlet #3, ''Dead1', which you were so kind as to send me for an examination. It was quite impossible for me to review the second draft at the time it came to me, but I have taken the time to review the third in some detail and to make numerous suggestions, fqu will find my comments attached to this letter. I am sending also a carbon copy for your convenience. I trust my comments will be found to be useful, and wherein they appear to be critical, I hope you.will recognise that it has been my purpose to be brief and to the point, and .yet, I hope, not arbitrary. There has not been time to cover the whole pamphlet, and thus, I have indicated my willing ness to follow through with my suggestions if your committee wishes me to do so. The revisions which I have suggested are based in large part on the content of the report of the committee on lead poi soning of the Industrial Hygiene Section of the &.P.H.A., of which I am chairman. We are preparing a rather comprehensive report, a portion' of which is completed and will soon be is sued. so far as it is feasible! to ,do. so, I have attempted to bring this pamphlet into harmony'with that report, with the idea that it would be disadvantageous -if the two were to clash with each other. On the other hand, If they are in essential agreement, they will strengthen each other measurably, espe cially in relation to compensation and other medico-legal con siderations. . : -** . Other corrections or suggestions have been based on the fol lowing purposes; (1) The removal of names so far as possible-, except insofar as definite reference to published articles can be cited; (2) The avoidance of controversial statements, par ticularly when they are unnecessary for practical reasons; (J) the avoidance of discussions of medical matters so far as pos sible so as not to raise too many medico-legal difficulties; (J4.) the elimination of relatively unimportant matters for the XB 0015725 Mr. R. L. Forney - (2) - October 11, l^l}-!, sake of brevity and conciseness; (' j } the correction of ungramatleal and ambiguous statements. In many instances the explanation for a given criticism or suggestion has been of fered in the paragraph.3 which I have prepared. Obviously, I do not expect your committee to accept my correc tions verbatim. I do wish, however, to stress the fact that every correction or suggestion which I have made has been based on careful consideration and on a.rather broad experience. I should particularly hope that any authorized pamphlet of this type would avoid controversy over certain relatively. unimpor tant matters and that it would not contribute to keeping alive a number of the misconceptions which have been disposed of by recent investigation. I wish to urge particularly careful attention to the question of analytic methods, i'he pamphlet, as represented in the third draft did not deal with this ques tion realistically. what I have done with, this portion may well be subject to Improvement, but the general manner of dealing with the problem of methods Is in lino with the judg ment of the people who have had the most experience in this field during the last ten years. I can speak not only for my self and my associates, but also for a number of others whose experience has been broad. Anything that is issued on this matter ought to be up to date and in accordance with recent experience. This matter Is, quite serious, since a very great proportion of the present confusion aa to the significance of analytical data is based on uncertainty and ineptitude in the choice of methods of analysis, lour committee, therefore, should be veny cautious in Its recommendation of methods and should not authorize the use of any method which is not pu blished in minute detail, And. which has not been tested criti cally by competent workers. Very truly yours, HAS ef Robert A. Kehoe, M. D. H 0015726 1 s&fijt . 1. "through teats and analyses of samples "--3rd line Change as .follows**-- "processes through properly designed operating, ventilating, and exhaust equipment"*-- ---- j.th line Ch&ng as follows---"V?hiie the avenues of feud absorp tion into the bony and the toxic effects therein will be covered"-- ---- -- -- -- 6th and 7th lines Page S&ssJi i Chang as follows-- -''precautions should bo taken against hasardous. lead exposure on the part of employees."--- Lines 2 and 1 f rom bottom Omit reference to slow absorption of load in oil as prac tically unimportant and change sentence as follows:"Tetraethyl lead is an oily, liquid, organic compound of load that is.dangerously.volatile at ordinary tempera tures* It is also readily absorbed through the healthy, unbroken skin, for these reasons, it .is a highly dan gerous material and mueihe manufactured and handled with grn.it ca,"0 against Inflation of vapor and contact with the skin. It is usedjchiefly as an anti-knock agent in motor gasoline to which it is aadeu-in low concentrations that do not give rise: to thef dougor of lead absorption among persona who handle and dispense gasoline, Tetra ethyl lean has also bden used in small'quant Itlea in the .tanufaoturo of other chemicals* Regulations governing the use of tetraethyl lead....*. .etc. n 8. Change as f o l l o w s ^ C o m m e r c i a l products containing lead compounds ar not always described or labeled in .such a manner that tbs. managers, foremen, or workmen in an Indus trie! plant or proceeds are aware .that they are using lead compounds, efheh such'commercial preparations are supplied for uae, it should be the practice of. the supplier to point out the potential lead hazard associated with the use- of . the product by employing suitable warning labels. Employees may. .,,,* .etc,13 ' " 10. Bo useful purpose is served by emphasising th factor of individual susceptibility, to do so encourages men to be lieve .that they can ward off effects that would injur weaker persons, .Moreover, there Is much lees validity In the idea of special susceptibility than is commonly be lieved. Still further the question of dosage Is so greatXy modified by the time factor thqt th acute toxic dose Is of little consequence in. relation to occupational lead exposure, The whole question of immediate toxicity should ' be soft-pedaled, therefore, while stressing the importance of avoiding unknown and uncontrolled exposure to all lead compounds. N19633.0] It is.also Important to avoid the discussion of the uncom mon effects of lead Intoxication and to call the attention of laymen to the more usual and characteristic effects, so 2 may raoo.gnis the. existence of danger on the other, I should revamp this paragraph as follows! "henever there la lead exposure there Is potential dan ger from the absorption of load "The de.-ree of danger depends upon the extent and duration of the exposure, The poisonous effects of load absorption are usually nianifda ted in one or more of the following ways* Cl) By disturbances of t lie digestive system, in the fora of loss of appetite, constipation, vague abdominal discomfort, and in more severe cases by severe cramping abdomin! pain (colic}; (2) By painful and stiff joints, bones, and muscles; (3) By general weakness, loss of weight, and pallor; ' Uj.) By loss cf strength in the fingers, hands, or forearms, and inability to use them In the per formance cf customary tasks; (5) Sy damage to the blood with the production of anemia.rt (Hots that no reference is made here to "stippling" or *lead line**. This omission is deliberate, and necessary, because those arc not "poisonous effects".) Too much stress has been put on kidney damage and injury to the reproductive system in connection with lead poi soning, These are definitely controversial matters from a medical point of view and should not be presented thus factually without adequate discussion. It is bettor her to omit reference to them by calling attention to the more common effects. Pa,g,e It -' 11 and 12.1 should omit these sections altogether. They give lit tle or no useful information to industrial executives, hy - gienlsts, or physicians, and they confuse the Issue, which is covered better In paragraph 13. Paragraphs 11 and 12 are technically erudite, but practically unimportant except to the toxicologist. This pamphlet is directed at the specific problem of prolonged occupational load exposure. The. issue should be stated, clearly by emphasizing certain statements In Paragraph 13 as follows: IJ. It must bo recognised that virtually all compounds of lead are poisonous if they are handled in such a manner as to be introduced regularly or frequently, in sufficient quan tity, into the air breathed by industrial workmen, or if they are t aken into the mouth and swallowed in sufficient amount over a long enough period of ti-ae. Some compounds 3 of lead are more dangerous than others for a variety of reasons. Some are more soluble in the tissues and fluids of the body than are others. Some of them must be employed or processed in a physical state that makes them difficult to handle without danger of exposure, Thus it may be feasi ble: in some instances to select a relatively safe lead com pound for a specific industrial purpose in place of one that would give rise to a much greater potential hazard, -'evercneless it should not; be believed that preventive mea sures can be neglected or reduced in effectiveness, because the compound or compounds in use are allegedly low in toxi city. Em s JL ,, ^ lq. Change as follows:-- head and its compounds can be taken into the body by inhalation or by ingestion (swallowing). (Tetraethyl lead Is readily absorbed through the skin. See paragraph 7) Inhalation of lead is by far the most com mon and moot dangerous form of industrial lead exposurd. It should not be assumed, however, that it is, unnecessary to warn and protect industrial workers against the ingestion, of lead compounds, and against careless and unnecessary skin contact with lead compounds. Every effort should be made to encourage and facilitate the development of care and clean liness on the part of workmen, not only to avoid lead absorp tion, but also to avoid dermatoses.** (I should require excellent evidence before I could accept the statement that lead In oil is absorbed in appreciable quantities through the healthy or Injured skin. Is there such evidence, either clinical or experimental? Unless the# is uncontrovertable evidence, this reference to it should be deleted entirely.) 15. Change as follows*--- ''The remainder is deposited on the sur face of the lung tissue from which it is absorbed and dis tributed into the tissues of the body." (It is unnecessary and: unwise to d escribe questionable physiological mechanisms. It Is quite improbable that lead is carried In the blood as the phosphate, and there is no point here in making a statemerit that most investigators will criticize. In point of fact practically all the lead in the blood is carried in the red blood corpuscles and no one hast he vaguest idea as to whether it is thei5 in organic or inorganic combination.) 16. Change as follows, and for similar reasons;--^eliminateaNJrd line through the feces. The greater portion of the lead which\ is absorbed from the astro-enteric tract is carried to the liver. It eventually finds its way into other tissues of the body and also back into the intestine by way of the bile," Page 6 17. Delete completely as repetitious and lacking in useful in formation. Tetraethyl lead is dangerous, not because it is absorbed directly into the blood stream, thereby short-circutting the liver, but because it goes quickly to t he organs of high fat content, that Is, the brain as well as the liver. It does not cause an immediate, but rather a delayed intoxi ad:9 'SE&26 2?. 28. Hevise as follows; Methods of Laaci Analysis. ifT?h@re ar a muabr o .general methods which can. b em ployed In the analysis of load dusta. Soma of Lhasa are squally satisfactory S or the analysis of loau In biologi cal materials after suitable preparation of such samples Thoraforo, it scams advisable at tills point to combine all descriptive references to analytical methods and their applications, so far as they cun be dealt with in this pamphlet. Only quantitative rethods are i-ciC*nfeloned, sin.ee w,o mero detection of lose in samples is without value, Methods based on orthodox chemical procoduro a whereby load is separated from other metals as the sulphide, sulphate, or chromate, ana determined finally by titrametrie, colori metric, or turbid .metric techniques have ceen described in numerous modifications by various r.eatl atora, ivies aro laborious and tiup-con 8uml ng, and are fraught with numerous technical difficulties* but they yield satisfac tory results in tho hunda of careful analysts, if the quantities of loa;: dealt with are sufficient In quantity, I.e, 0.2 nililrrama or vsore. nsforenccs to articles de scribing these methods 'rill be fur-nished on z-o ^uosl., but sii.ee there matnodo have boon largely wispluced in recent years by more sensitive, more accurate, and .tor convenient methods, they will hot b diecusoed further. (Keferencea yivon out hero should induca not only Pairhall's method, but curtain modifications and. improvements in it that have been described much more precisely than Pairhall's, They should also include other methoda based on chemical separatQX'7 .rineiplos, a number of which have proved their worth in tho hands of Australian, British, -nd American Investigators. Fairly complete reference to these can be found In a number of papers or? methods'. I shall be glad to supply them on request.) Bsvoral electrolytic techniques for fee determination of load have been, described and employed with reasonable suc cess by vsr|qs..investigators,. These, too, except for cer tain United applications have boh'superceded .to a largo extent by methods developed mor recently. Various modifications;, of tho Fischer-Loopoldi method* (aiding us of dlthixom (diphenylthio carbason) as a means of extracting:lead quantitatively from Its aqueous solutions to -forraa colored complex), have been developed in recent years and have cosas to occupy first place among procedures for the determination of load, The method is sufficiently sensitive to deal with the minute quantities of lead present in small samples of urine, blood, and tissues, and when properly carried out, it is specific for lead and quantitatively 'precise. Several of the modificaticos ha.i- been described In step-by-step detail and can bo relied upon implicitly when amployad by careful and experienced analysts. Among those used extensively with 5- a variety of materials are the methods described by Clifford and ^lchmann, by Alikins, llloughby, and Xrasmer,a nd by Hubbard. 9. Spectrographic analysis of materials containing lead can be carried out with extreme sensitivity and with accuracy equivalent- to that of the bast dish!zone methods, he metnod requires highly specialized and costly equipment, and therefore, it is not widely used* because of this limitation, further discussion of it will not be under taken hero* deference can be made to the papers of Chol&k, et al for details of the technique. 30. Here use paragraph 28 with modifications beginning with line 3 as follows: "lt has in its favor the use of com paratively simple technique and somewhat greater spaed in the final determination of lead, with this as with other methods, however, the preparation of samples re quires tire ana care, and thereby, a considerable limi tation of the speed of analysis is imposed, then properiy handled, the method will yield results comparable in accuracy with the aithizone and spoctrogr&pnic methods." defer hero to the paper of Bambach. rage 9 30, maximum permissible .concentration (This will become pi If previous recommendations are followed.) Correct first sentence to a void repetition of "permissible" and "per mitted"; "The lead concentration in workrooms should not be permitted to exceed-- -"etc. bjgns of lead foisonina Pages 10 21*. and 12 This section of the pamphlet should be revised drastically, in my opinion, not so much because it is incorrect in its facts, as because It is not directed either to laymen or physicians in such a way as to provide clearly the infor mation required, The layman will not understand the sim ple facts which he should haveybecause they are mixed in with strictly medical and physiological considerations. The physician will not accept the medical Information be cause It is not presented in the manner to which he is ac customed, The discussion, therefore, while fairly clear to the specialist, is both too much and too little to ac complish its purpose. In ay opinion the discussion of normal lead absorption and the evidences of Increased lead absorption should be included in the previous section on "The Action of toad and Lead Compounds on the Body", since this information concerns lead absorption and could well follow the paragraphs on the "Entrance of lead into the body", just -before "Testing for Presence of head in Air and Analysis of sample", buoh an arrangement would per mit the Inclusion of a later section for the information of physicians, on "CMnical types of lead poisoning and -6- the diagnosis of lead poisoning"* this to bo--substituted for the section now entitled t{Tigris if -bead Poisoning", fuch. a section, prepared by a physician for physicians, could be a brief but adequate statement of the present status of the subject, with a few well chosen references to the literature, inatoau of the partial quotation of authorities I should be glad to assist in the prepara tion of such a asetivu in any way possible, hut I cannot develop my suggestions in tine. to meet the dead-line cot up in the letter accompanying the draft, I shall also be glaa to Suez-lit this section of the report of the Commit;teo on Lead foiconing of the i.P.H.A. as soon as it has been coou)l(itu, for such use us it nay be here, On the other hand, if it la necessary to issue this pUKphlnt quits soon, I should suggest eliminating this ruction, noroll:/ adding suitable laforciation to the layman to the section on 'l?he lotion of Lead and Iliad 'compounds on the sorly", 8/hile i nave not h&a. bica to raview th remining storiai in minute .dettali* it seoais to m to be very s&llafhotory* excepfc for che last page* on whioh tha load flndlnga In th urine are espresse*! in non-^wantit&tive ter/as. I &g aure w?, Krorsenberg wouid Alali to aodify tLia to include quantitativo limite in th *#e t th `trine, ueferenee rolgfcb al so te j&ado to th quantitative anslytical findlngs in'he biood. H 0015732