Petros Koutrakis

Professor of Environmental Sciences
HSPH Department of Environmental Health

Dr. Koutrakis’ research activities focus on the development of human exposure measurement techniques and the investigation of sources, transport, and the fate of air pollutants. In collaboration with his colleagues in the Environmental Chemistry Laboratory, he has developed ambient particle concentrators and high volume samplers that can be used to conduct human and animal inhalation studies. He has also developed a personal ozone monitor, a continuous fine particle measurement technique…

Nima Hejazi

Assistant Professor
Department of Biostatistics, Harvard T.H. Chan School of Public Health

Nima Hejazi, PhD, is an Assistant Professor of Biostatistics at the T.H. Chan School of Public Health of Harvard University. He completed an NSF Mathematical Sciences Postdoctoral Research Fellowship, and, before this, obtained his PhD in Biostatistics from UC Berkeley. He was on the founding core development team of the tlverse project (, an extensible ecosystem for targeted learning in the R language, and, since 2020, has collaborated closely with…

Photo of David Christiani

David Christiani

Professor of Environmental Genetics
HSPH Department of Environmental Health

My major research interests are occupational, environmental and molecular epidemiology. I have been interested in studying the impact of exposures to various pollutants on health and the interactions between host factors (genetic and acquired susceptibility), and environmental exposures in producing acute and chronic diseases. This research is part of a field known as molecular epidemiology. I have been active in developing new methods for assessing health effects after exposure to…

Jiyoung Son

Associate Research Scientist
Yale School of the Environment

Dr. Son is an epidemiologist with a background in biostatistics and a focus on environmental health. Her research focuses on 1) estimating the health impacts from environmental stressors on human health; 2) methods for estimating exposure to environmental conditions, primarily air pollution and weather; 3) the health impacts of different types of airborne particulate matter based on their chemical structure and sources; 4) effects for subpopulations, such as by gender…