Dr. Giffe Johnson is a Research Assistant Professor at the University of South Florida College of Public Health in the Department of Environmental and Occupational Health.  Dr. Johnson has published and presented research on a variety of topics related to environmental and occupational health including environmental benzene risk assessment, occupational exposure to asbestos, and substance abuse epidemiology in the emergency room.  Current research activities include pesticide biomonitoring in agricultural workers, the effect of poly (ADP-ribose) polymerase (PARP) inhibition on chemical induced toxicity, and conducting large scale occupational health surveillance using secondary data sources.