Document B5QN2e8o54Gyq46mYG7oN244

d e pa r t me n t o f pe d ia t r ic s VANDERBILT UNIVERSITY SCHOOLOF MEDICINE NASHVILLE. TENNESSEE December 16, 1938. Dr. Robert A. Kehoe University of Cincinnati College of Medicine Cincinnati, Ohio. Dear Doctor Kehoe: I thank you for taking time to write me your long and inform ative letter of December 13th, also for the enclosed reprints and for al lowing me to read the two unpublished papers which I am enclosing herewith. This letter made very much clearer to me,than did the letter forwarded from Dr. Hooker, the basis of your criticism of my'review. There are certainly two lines of approach to the lead problem, one a primarily cuanitative one and the other more a qualitative one. The first which places chief emphasis on the quantitative aspects of absorption, retention and ex cretion of lead at various levels of exposure, and which evaluates the lead hazard in terms of whether or not the amounts of lead involved may be expected to produce clinical signs of plumbism is the line of approach ivhich you have followed in your long and valuable researches. The other point of view to which I gave rather more space in my review is chiefly concerned with how the presence of lead influences the normal chemistry and physiology of the body. I think we would both agree that both lines of approach are important, closely related and that they will eventually come together. In terms of physiological and chemical effects there is probably only a quantitative and not a qualitative difference between the actions of concentrations of lead too small to produce symptoms of poisoning and those slightly higher concentrations which ssaAet pro duce recognizable signs of intoxication. Even when one deals with frankly toxic amounts of lead there is a wide individual variation in the degree of physiological abnormality associated with a given quantity of lead. It seems likely there may still be this quantitative^variation 'when dealing with smaller amounts of lead-- yet qualitatively leadMsmfc Exerts the same influence on physio logical processes and structures in every subject. To my mind a real under standing of the toxicology of lead and an evaluation of the danger from minute amounts of lead must eventually come from an understanding of the kind of changes which lead brings about in the organism^. Admittedly we are a long way from such an understanding, and likewise admittedly we have made more real progress along the quantitative aspects of the problem. Quite possibly I dis missed too briefly what is known in terms of quantitative relationships to dwell at greater length on unfinished work which appeared to me to be fruitful and suggestive along the line of the physiologicaiyeffects of lead. This choice of emphasis was probably partly dictated by the direction of my personal inter est and more by what it seemed to me the title of my paper would make a reader expect to find emphasized in the review. Vie might argue fruitlessly all winter as to the relative merits of the two approaches but that would be of little value. I do, however, appreciate your constructive criticism. I have learned a lot in the course of writing this paper but the lesson I have learned best is "never be persuaded to write another review. HE 0012430 N131S0