Dr. O'Rourke has conducted interdisciplinary research relating environmental exposure to human health for more than 30 years. Throughout her career, she has worked on aggregate and cumulative exposure to a variety of agents including pollen, mold, house dust mites, metals (particularly arsenic) and pesticides (particularly organophosphates. These studies include the National Human Exposure Assessment Survey, the Arizona Border Survey, two surveys examining pesticide exposure among children in Yuma Co. Arizona, pesticide exposure in the Gila River Indian Community and arsenic exposure through food. She has extensive experience in designing and implementing exposure assessment field surveys, quality assurance programs and the data processing protocols for large studies. Her current research, in collaboration with Dr. Harris, focuses on multimedia, multipathway exposure to PM2.5, arsenic and uranium among the Hopi of Arizona.