Document 3Lg7B962063ExKJZ0RGDaEOn

October 13, 1952 M r . S . R. Wiley Mr. R. Jacobs Research Center Johns-Manville Corporation Manvilie, New Jersey Gentlemen : Having had requests from both of you for analytical methods for :lead in biological materials, I forward such information in the form of reprints from the literature. I gather from the statements in the two letters that your company has not applied analytical methods of control previously, and that neither of you has had experience in the use of the methods of analysis for lead in biological material. If this is true, I cannot, warn you too strongly against attempts to put such methods to work, and especially against any efforts which may jbe required of you in the Interpretation of such analytical results. As to the analytical work, whether chemical or physical in type, the [pitfalls involved in the frequency with which samples , equipment and chemicals are contaminated with lead are wholly beyond one's imagination, regardless of his technical profi ciency, unless he has had experience. The techniques are highly exacting, and the environment of the laboratory in which one works must be made meticulously free of all foreign materials i- ' ' As tp the type and quantities of samples to be obtained, and the ^nethods of obtaining them, the problem Is difficult and requires detailed knowledge of the sad experience of all who have] gone before and learned In the hard way what not to d o . In short this Is no job for a novice. Specific training and experience are necessary to avoid serious mistakes and painful experiences. The InterpretatJm of the results of 3uch analyses is essentially a medical job. Proper Interpretation requires a background of physiological knowledge, and a consideration of the medical features of the general hygienic problem. You may suspect that in saying this I am attempting to protect the prestige of the physician, but such is not the case. I know from wide experience the difficulties that have arisen when non-medical people are asked to assume medical responsibilities in this very matter. licrode termination of Lead in Biological Material With Dithizone Extraction at high pH - Cholak, Hubbard, Burkey Mr. S. R. Wiley and Mr. R. Jacobs - (2) - October 13, 1952 Everything will be all right so long a3 the lead exposure which you are asked to measure is kept within safe limits, if and when it is or becomes dangerous, you will be on the spot, and you will not be able to deal with the situation. For this reason, there must always be a coordinated effort betwe the analyst, who should assume no responsibility for the interpretation and application of the results, and the medical man, who only rarely has the knowledge and skill required to do the analyses. The physician should see to it that the right type and amount of sample is provided for analysis, while the analyst should see that the samples are obtained, in such a manner (equipment, surroundings, containers, etc.) that they will not be contaminated. (Ho-matter what you do, they will be contaminated occasionally, but unless you provide proper precautions they will be contaminated so regularly that your work will all be in vain.) The articles being sent you will provide part of the help you need, but you will be able to save yourselves much time and untold grief, as well as no little expense, if you will pay us a visit and see at first hand the facilities^equipment and procedures that are necessary to obtain usefur/reliable results. I would suggest'that yourselves and a physician; of your company might well visit us for a discussion of your problem, and that one or both of you plan to stay long enough to go through the steps of the procedures and to acquire a sound knowledge, not so much pf the routine technique, although that will be valuable, but of the pitfalls that must be avoided if you are not to repeat all or most of the mistakes that others have made in arriving at sound procedures. May I also urge you to consider seriously what I hare said about the medical part of this problem If you are not to have the help and guidance of a physician in certain aspects of the program, it is highly questionable in my mind as to whether or not you should allow yourself to be drawn into it. Very truly yours, RAK ef Robert A. Kehoe ," H7~5T Enc. Quantitative Speetrographic Determination cf Lead in Biological Material - Cholak Determination of Lead in Biological Materials - Comparison of Speetrographic,Dithizone, and s-Diphenylcarbazide Methods - Cholak, Hubbard, McITary and Story Speetrographic Analysis of Biological Material III. Lead, Tin, Aluminum, Copper and Silver - Cholak and Story determination of Lead in Biological Material - Cholak and Bambach l n d CCholakiC Deposition of Lead from Biological Material - Bambact Spectroche/mlcal Determination of Trace Metals in Biological Material - Cholak ana Story