The NIEHS Superfund Research Program (SRP) presents the second session in the Risk e-Learning series, The Interplay Between Environmental Exposures and Infectious Agents. The seminar series examines the interactions between environmental exposures and infectious agents in the development of disease. The series will highlight researchers from around the country who are doing innovative research to better understand this relationship between environmental exposures, infectious agents, and immune response. In this session, researchers will present innovative research to better understand how environmental chemicals alter immune response. Philippe Grandjean, M.D., D.M.Sc., a professor at the Harvard School of Public Health, will describe his research linking elevated exposure to perfluorinated compounds with reduced immune response to vaccinations. Bruce Stanton, Ph.D., a professor at Dartmouth College and Director of the Dartmouth SRP Center, will discuss his research on the effects of arsenic on Pseudomonas aeruginosa infections in the lung by adversely affecting the innate immune response. Inorganic and organic forms of arsenic, at levels relevant to exposures in the US, have adverse effects on cytokine secretion by human bronchial epithelial cells and macrophages, thereby disrupting the ability of the lungs to clear bacterial infections. Syed Hashsham, Ph.D., a professor at Michigan State University (MSU) and MSU SRP Center project leader, will talk about the ongoing research related to the role of keystone bacteria in modulating the immune system and their interaction with the host in response to dioxin exposure. Concepts related to microbial community modeling and tracking will also be presented. To view this archive online or download the slides associated with this seminar, please visit http://www.clu-in.org/conf/tio/SRPInterplay2_103116/