Document pZ706G84me0yOLG2nD7XjXNk

K 00122 t t. it / April 7, 1955 Mr. K. E. KesselUerg Ethyl Corporation Research and Development Department Research Laboratories 1600 West Eight Mile Road Furndale 20 Detroit, Michigan Dear Howard: I have gone over your memo with some care, and have made a few editorial suggestions. As I anticipated, there was little need for such editing, but I have added a bit here, and changed a sentence a bit there, and perhaps I've improved the text somewhat. I return it herewith. You have certainly extracted the essence of the argument with the possible exception of one idea, whieh is implied but not expressed. I refer here to the fact that there ha3 been no progressive change in the general pattern of the excretion of lead, as observed in fair sized segments of our population (represented in the groups of persons examined in various surveys including the last one which began in 1955), during the last ten or fifteen years in which the methods of investigation have been substantially constant. It has been demonstrated that groups of people respond fairly promptly to increases in their exposure to lead by excreting lead at an increased rate. The failure to show such response, therefore, means that the increase, if any, in the general exposure to lead, has been insignificant. Thanks for letting me see this. Cordially yours. RAK:ss Enclosure. Robert A. Kehoe, M. D. He 001P.9i.ii