Federal Role in Responding to Potential Risks of Per- and Polyfluoroalkyl Substances (PFAS) David M. Bearden, Coordinator Specialist in Environmental Policy Jerry H. Yen Analyst in Environmental Policy Mary Tiemann Specialist in Environmental Policy Elena H. Humphreys Analyst in Environmental Policy October 23, 2019 Congressional Research Service 7-. www.crs.gov R45986