Dr. Chen is a senior environmental epidemiologist who focuses on perinatal, pediatric, and aging outcomes and a variety of exposures: lead, mercury, cadmium, DDT, isoflavones, flame retardants, perfluoroalkyl substances (PFAS), air pollution, and electronic waste recycling. He has established international studies to examine chemical mixture exposure from informal e-waste recycling in resource-poor communities and has raised awareness of the potential chemical toxicity to pregnant women and developing children; these efforts have impacted policy making and prevention. He has systematically investigated thyroid hormone disruption and developmental neurotoxicity in children from prenatal and postnatal exposure to polybrominated diphenyl ethers (PBDEs), PFAS, organophosphate esters (OPEs) and replacement brominated flame retardants (RBFRs), using the Health Outcomes and Measures of the Environment (HOME) Study, a Cincinnati-based pregnancy and birth cohort with repeated childhood and adolescence follow-ups.  

Dr. Chen is currently investigating chemical mixture exposures and child neurobehavior using U.S. and Canadian birth cohorts. He also examines exposome and cognitive aging. He is involved in and is curator of the Treatment of Lead-exposed Children (TLC) Study, a placebo-controlled multi-center randomized clinical trial at sites including Philadelphia, following its completion at the National Institute of Environmental Health Sciences (NIEHS). He is an Associate Editor of International Journal of Hygiene and Environmental Health and serves on the editorial review board of Environmental Health Perspectives. Dr. Chen is Associate Director of the Translational Research Support Core (TRSC) in the NIEHS-funded Center of Excellence in Environmental Toxicology (CEET) and is Co-Director of the NIEHS-funded Philadelphia Regional Center for Children's Environmental Health (PRCCEH).