Document aBw8J4L9K1gOzXgEeY2zwpeVX

April 19, 1973 Dr. George Wetherill Professor Department of Planetary and Space Science UCLA Los Angeles, California 90024 Dear Doctor Wetherill: I have had the pleasure of examining your proposal for an investigation which should, I believe, make it possible to determine the proportion of lead which is absorbed under ordinary conditions of life in the respiratory tract of man as compared with that absorbed in the alimentary tract. (I shall not go further to describe the objectives of your investigation, since, I believe, what is said above will be sufficient for the identification of your proposal to the National Science Foundation.) I and my associates have been studying the metabolism of lead in man for many years, ana have been unable, as yet, to solve this problem. I am most anxious, therefore, to learn the outcome of your observations at the earliest possible time. 1 am also prepared to be of such service to you and your colleagues as I may. I am not at all presuming that any such service will be desired or needed, but we have not published many of the details of our work on human subjects over the period of thirty-odd years, and I may be able to be helpful in some measure. Certainly, I am highly interested in your approach to the matter and excitedly interested in what comes of it. It seems to me very likely, indeed, that you will obtain valid answers to certain primary questions, as well as significant leads into other physiologic phenomena. Incidentally, my own investigations will hardly continue on for many more years, and to the extent that they go on, they will be concerned mainly with some additional features of occupational exposure to lead compounds, such as, for example, the variability of the absorption of various compounds of lead. The hazards of occupational exposure to lead have never been examined thoroughly, and the need for additional information is very great. I hope to be able to extend our observations into some of the dubious areas, and certainly one of those relates to respiratory exposure to, and absorption of, lead compounds under a variety of conditions about which we know very little for certain. With best wishes for the progress and success of your efforts, and my kina regards, Sincerely yours, RAK:wb Robert A. Kehoe, M.D. Professor Emeritus of Occupational Medicine