Dr. Rich's research focuses on the cardiovascular, respiratory, and perinatal/reproductive health effects of exposures to environmental agents including ambient air pollution. He is an environmental epidemiologist whose research is directed at understanding not only if specific environmental agents impact health, but also by what pathophysiologic mechanisms, by what environmental pollutant or mixture, and in what potentially susceptible sub-group of the population. Working with a large collaborative air pollution research group, he also studies whether different air pollution mixtures, sources, and components impact cardiopulmonary and reproductive events and biomarkers of different pathophysiologic mechanisms underlying such health effects.