Document Y9e5BOXJqmQbJQg1rLMnNKd8

February 9, 1971 Mr. Louie Hernandez, Jr. 250 De Neve Circle Los Angeles, California Dear Mr. Hernandez: I'm afraid that the subject on which you are writing your thesis has very little to do with "inhaled particulate lead," but a much more pertinent part of the work in the Kettering Laboratory, by myself and associates, namely, the lead in food and beverages, will be referred to in a booklet which Z am sending to you. Xn this same booklet will be found some reference to the fate of inhaled particulate lead compounds. t I should make it clear to you that some of the lead in food is not the result of contamination, but is rather lead in the food as it is found in vegetation, its fruit and its roots, and in animals as well as men which have fed upon vegetation and other animal forms. The effects of lead on biological systems should also be understood as being dependent, in large part on the quantity taken in, in one way or another. So far as we or anyone else knows, man has always had lead in his body, his food and his beverages, including water. We are not sure of the amounts taken in earlier times, but certainly for the last half century, the amounts taken in food and beverages have been very similar. Only when the quantities involved are very much larger than those wi h1ich occur regularly, do they cause any illness or injury. The means by which such contamination occurs are varied, but they have nothing to do with thelead which is inhaled with the ambient air. One could write a book about the manner in which food is contaminated with lead, as the result of spraying, shipping, processing, canning, and preparing in the household for eating. The containers in which food materials are stored in the household and elsewhere, the kettles, skillets and pans in which they are cooked, and the tableware, drinking glasses and mugs, as well as the knives, forks and spoons used - all of these are important - o r may be if composed of the wrong materials. As a matter of fact, processed foods in the united States are remarkably clean, and they are packaged in such a manner as to keep them clean. This is all very good from the aspect of hygiene although there is some doubt about such matters as appetizing flavor. What I mean .to say, however, is that the contamination of food and beverages with lead in the iUnited States is not much of a problem. You should be careful, therefore not to speak of these matters without being very sure of your facts, since the cases of lead poisoning that occur in the United States are very rarely due to contaminated food N5996 Mr. Louie Hernandez, Jr Page 2 February 9, 1971 However, Z must leave the thesis to you and hope that you will be sufficiently interested in the truth of the natter to exercise considerable care in documenting your story and its conclusions. I am sending a paper bound booklet of a series of lectures which I gave in London in 1960. More information is available since that time, but this still presents facts which have changed very little since the third decade of the present century. With best wishes for the success of your efforts, Sincerely yours, RAKjwb Robert A. Kehoe, M.D. Professor Emeritus of Occupational Medicine