He studies environmental health risks in developing countries, the health impacts of climate change, and the role of the urban environment in shaping health. For the last several years his primary focus has been the health effects of exposure to indoor air pollution from biomass fuels. With support from the Center for Environmental Health in Northern Manhattan, he has helped to develop a Columbia-wide biomass working group, which coordinates and supports interdisciplinary research on the topic. These collaborations have given rise to current efforts to measure the health benefits of clean cookstoves in Ghana, Kenya, and India. He holds a Ph.D. from Harvard University and an undergraduate degree from Williams College.