Dr. Kleiman is an expert in environmental exposures and their health effects in both humans and animal models. Current NIH funded research focuses on defining those genetic, epigenetic, serological, environmental and social factors that influence response to COVID-19 infection, potential risks for long COVID, and potential of breakthrough infection. In addition, Dr. Kleiman is helping lead a federally funded safety study designed to evaluate potential human ocular and skin risks from exposure to farUVC radiation, an emerging approach to combat airborne pathogens, and SARS-CoV-2, in particular. Dr. Kleiman’s other funded research interests include examination of the health effects arising from acute and chronic radiation exposures with particular emphasis on ocular manifestations, as well as health effects associated with exposure to toxic and heavy metals, and, in particular that arising from e-cigarette use. Dr. Kleiman directs a Radiation Safety Officer (RSO) Training course required for a Nuclear Regulatory Commission Type C license and his institutional responsibilities include serving as Vice-Chair of the IACUC, Chair of Faculty Steering and a member of the Columbia University/Irving Medical Center Joint Radiation Safety Committee. Dr. Kleiman serves as an expert for a variety of domestic and international regulatory and advisory bodies and serves on the editorial boards of a number of peer-reviewed academic journals. His research has led to insights into how ionizing and UV radiation damages the eye and causes visual dysfunction as well as how individual genetic determinants influence radiation risk. His laboratory was the first to report that arsenic exposure leads to bioaccumulation in the eye lens. More recently, his NIEHS funded research reported on metal exposure risk arising from e-cigarette aerosol exposure. These investigations help inform and guide current human exposure guidelines for environmental hazards and have therapeutic implications for sensitive subsets of the human population.CoronavirusSARS-CoV-2Long COVIDCOVID-19BiodosimetryIonizing RadiationChernobyl Nuclear AccidentRadiation CataractRadiation Health EffectsPublic HealthOphthalmologyOcular AnatomyEye LensArsenicE-cigarettesVapingHeavy metalsOxidative StressDNA Damage and Repair