After much anticipation in the environmental community, EPA has announced proposed enforceable drinking water standards for six PFAS compounds, including PFOA and PFOS.

Unlike the agency’s two prior health advisories, these maximum contaminant levels (MCLs), if finalized, will set legally enforceable compliance standards for drinking water. Of interest is that EPA set the new proposed MCLs for PFOA and PFOS at the practical quantitation level (PQL), defined as the “lowest concentration of a contaminant that can be reliably achieved within specified limits of precision and accuracy during routine laboratory operating conditions.” According to EPA, “EPA has determined that PFOA and PFOS are likely carcinogens (i.e., cancer causing) and that there is no level of these contaminants that is without a risk of adverse health effects. Therefore, EPA is proposing the set the MCL for these two contaminants at four parts per trillion, the lowest feasible level based on the ability to reliably measure and remove these contaminants from drinking water.” Thus, although the proposed enforceable MCLs are higher than EPA’s 2022 Health Advisory for PFOA and PFOS, which were set based on health risks, the proposed new MCLs are still set at essentially the instrument detection levels.