Document evG0ErGbxBBRvJZxxKpgMLkpM

March 12, 1973 Waldo E. NelS on, M.D., Editor The Journal 6f Pediatrics 3300 Henry Avenue Philadelphia Pa. 19129 Dear Waldo: I consider that Doctor Rosen has replied satisfactorily to my critical review of the article iay himself and his colleagues as originally submitted. It was not my intention to be carpingly critical of him and his paper. As a matter of fact, I do not take pleasure in being hypercritical, and I hardly think I am full of prejudices toward other authors on the subject in question. Indeed, I was very much inclined to recommend the acceptance of the paper by the Journal of Pediatrics. However, with the assistance of Mr. Cholak, we looked at this very problem some years ago and found that the concentration of lead in the blood plasma was so low that we were unable to demonstrate at once, significant differences between the so-called no hmal findings in this respect and those obtained from persons with lead poisoning an high values of lead in the whole blood. I did not believe that our total set of methods, as applied, were sufficiently precise to detect such differences (which I considered, almost certainly, to exist) and dismissed the matter for later examination. I was not prepared to accept that Rosen's findings had demonstrated the true facts, without the necessary evidence which, therefore, I demanded. It was this experience, which led me to look skeptically, at his data and to take the position thajt his data should not yet be published. This, as you will believe, of course, is a; important matter in the physiology of this angle of the metabolism of lead. I suff t. , also, of course, from the lack of a proper critique, when it comes to analytical methods, in which, as you know, I am no expert. Incidentally this issue bedevils a great deal of the published work on the trace metals, so that I have had to move extremely carefully in my acceptance of the truth concerning a correct series of concepts. Things have moved very rapidly in this general fiel^i, and many ambitious persons have entered themselves into the acts. I find it excehdingly difficult to absorb and appraise the multitude of technical methods which have been applied in the attempt to examine the facts, for actually the issues he re relate to an understanding of details of human physiology, many of which were mt even dreamed of only a few decades ago. At any rate, let me say that I shudder, as do many other investigators, at the multiplicity and complexity of the physiological problems with which we have to deal in our appraisal of the present human environment in our efforts to arrive at the proper course. RAK:wb Sincerely yours, N6118 Robert A. Kehoe, M.D.