Document gE66O54zMg9kBXbDMwr1NverN

A ,DIVISION OF THE e -f a r t me n t o f p u b l ic w e l f a r e Ba l t imo r e Cit y Ho s p it a l s 4940 EASTERN AVENUE BALTIMORE 24, MARYLAND Sept, 15, 1969 IN REPLY REFER TO; Dr. Robert A. Kehoe Professor Emeritus of Occupational Medicine Department of Environmental Health Kettering Laboratory, College of Medicine Eden and Bethesda Aves. Cincinnati, Ohio 45219 Dear Dr, Kehoe: Many thanks for your letter of July 21, 1 969, I am certainly in agreement with the points brought out in your letter, I am writing at this time because my thoughts have changed a little bit since my last letter to you with respect to the determination of lead in blood on capillary samples of blood. Although obtaining a capillary sample by finger prick maybe quite appealing from the public relations point of view, it may indeed introduce a significant variable from the analytic point of view. Thus the hematocrit on the capillary sample may vary significantly from the hematocrit of a venous sample, which could intro duce a significant variable with reference to lead. For this reason, we hope to try small venous samples and will, in the course of the study we are undertaking, determine how easy it is for the usual house officer to obtain one to three ml of blood by venapuncfure from very small children. I shall let you know how this progresses. It would not change the analytical procedure and might improve the reliability. 1 hope you will keep me informed, as we would be glad to try any promising analytic technique in the study we are undertaking during the next 12 months. I may add that the emphasis in this study is on the reliability of analytical and sampling procedures rather than on the incidence aspect of the problem. I do plan to be at the APHA meeting in Philadelphia in November, and hope possibly to have a chance to meet you then. Yours sincerely. JJCto.v /J. /Julian Chisolm', Jr.,} M. D. HE 0020215