Biden EPA finalizes first-ever mandatory PFOA and PFOS drinking water limits at 4 parts per trillion

The Biden EPA finalizes the National Primary Drinking Water Regulation setting enforceable maximum contaminant levels for six PFAS chemicals — PFOA and PFOS individually at 4 parts per trillion, with a maximum contaminant level goal of zero based on identified cancer risk. The rule also sets 10 ppt limits for PFNA, PFHxS, and GenX chemicals. Public water systems serving 66,000+ utilities must complete initial monitoring by 2027 and achieve compliance by April 2029. EPA projects the rule will reduce PFAS exposure for approximately 100 million Americans.