first scientific society founded 1833 in America. In 1948 he was Chief of the Mexican Delegation of the World Health Assembly in Geneva, during which his initiative and efforts helped to establish the Division of Environmental Sanitation and the Panel on Brucellosis. He received the first award of Physiology of the Mexican Society of Internal Medicine and the Gold Medal and Diploma for Public Health Merit of the Department of Public Health and Public Assistance. Silver Medal, Gold Medal and Diplomas for 25, 30 and 35 years of Professorship of the School of Medicine National University of Mexico, have been awarded to him and other honours include: Gold Medal and Diploma for Health Merit, Mexican Public Health Association; Diplom for the Foundation and Distinguished Services, National Committee Against Tuberculosis, Mexico. Honorary membership Inter American Statistical Institute. For 40 years León was member and vice president of the American Public Health Association. He published 1992 his book 50 Years Of Investigation In Mexico Marquéz López Editorial Inc. In 1979 Leon started to conduct a research on cancer treatment. Unfortunately because of his old age he could not publish a scientific publication of the successful therapies cases applied. Nevertheless, he was able to cure some cases of cancer sick patients in his practice, and most of those where hopeless cases. He married 1934 María del Refugio Lomelí Sánchez in Mexico City and they raised 9 children. References The author taken from: International Who's Who of Intellectuals. Quiminet entry on Leon External link 1909 births 2001 deaths Mexican public health doctors Mexican expatriates in the United States National Autonomous University of Mexico alumni David Geffen School of Medicine at UCLA faculty Harvard School of Public Health alumni