The research in my program involves the development and application of molecular biomarkers of exposure, dose, and effect from environmental carcinogens. The environmental carcinogens studied include agents that are naturally occurring in the diet as well as those produced as a result of cooking practices. A major emphasis of the research has been in the elucidation of the role of aflatoxins, a common contaminate of the food supply, in the induction of liver cancer in high-risk populations living in Asia and Africa. This work has led to the identification of a very strong chemical-viral interaction between aflatoxin and the human hepatitis B virus in the induction of liver cancer. These biomarkers have also been used in many collaborative molecular epidemiology studies of liver cancer risk and recently employed to assess the efficacy of a number of chemopreventive agents in trials in high-risk aflatoxin-hepatitis B virus exposed populations. This research is now being extended to develop genetic biomarkers of p53 mutations and viral alterations in human samples as early detection of disease biomarkers using a novel mass spectroscopy based method for genotyping developed in the laboratory. Thus, the research in our laboratory focuses on the translation of mechanistic research to public health based prevention strategies.