USEPA’s May 18, 2022, Regional Screening Level (RSL) update included the anion and acid forms of several per- and polyfluoroalkyl substances (PFAS), providing residential and industrial soil screening levels; soil screening levels for protection of groundwater; and tapwater screening levels. 14 PFAS included in USEPA RSL Update ammonium perfluoro-2-methyl-3-oxahexanoate hexafluoropropylene oxide dimer acid (HFPO-DA) (aka, […]