Document wry8ZMedLEYgE0baXNZOGj7mV

i? V . / ^ "<Dlt UNITED STATES ENVIRONMENTAL PROTECTION AGENCY HEALTH EFFECTS RESEARCH LABORATORY RESEARCH TRIANGLE PARK NORTH CAROLINA 27711 DATE: October 24, 1984 SUBJ: Review of work on Blood Lead and Blood Pressure by Pirkle and Schhwwartz */ J FROM: Victor Hasselblad, Ph.D. Biometry Division, HERL (MD-55) TO: David Weil, Ph.D. ECAO (MD-52) The paper, and the work done in connection with the paper, represent a comprehensive examination of the relationship of blood lead and blood pressure. The authors have examined all possible factors available from the study, and have extracted maximal information from them. I know of no serious flaws in their work. There is one word of caution that needs to be made. The use of logarithms of the independent variable forces an infinite slope of the dose response curve at th^ origin. It also forces a flat curve for large values of the independent variable. This may or may not reflect reality. In any event, the use of the dose response curve in the low and high range of the independent variable is extremely dangerous. TEH 0350093 N36697 DUP050298722