Tongzhang Zheng is Professor of Epidemiology (environmental health) at the Yale School of Public Health. He received a D.Sc. from the Harvard University in 1990. His research interests have been in the area of environmental pollution and human health, particularly in cancer epidemiology and aetiology related to environmental hormone disruptors, genetic susceptibility and gene-environmental interaction. His research emphasizes the role of organochlorine compounds (such as PCBs, DDE and other pesticides) in the aetiology of several major cancers in the United States including breast, Non-Hodgkin lymphoma, Hodgkin’s diseases, multiple myeloma and testicular cancer. Tongzhang Zheng has considerable experience in conducting epidemiological studies in China. He is the Principal Investigator (PI) for a National Institutes of Health (NIH) training grant studying air pollution, temperature changes and human health in 6 different cities with different types of air pollution in China. He is also PI for a case-control study of liver cancer in China and serves as Co-Investigator for a case-control study of indoor pollution, gene polymorphisms and risk of lung cancer in Xuanwei County in China. In 2007 he received an Honorary M.A from the Yale University.