As the director of the Southern California Particle Center and Supersite, a research center dedicated to looking at air pollution and its health effects, Dr. John Froines' work attempts to answer the question, How does particulate matter in the air harm the body? In addition to his air pollution research, Froines also looks at the carcinogenic risks of certain substances, such as arsenic and chromium. He has conducted extensive research on pesticide exposure in Mexico and as the chairman of the California's Scientific Review Panel, he reviews data on proposed toxic air contaminants to ensure the appropriate applications of science and risk assessment.