U.S. EPA Announces New National Primary Drinking Water Regulations for PFAS

On April 10, 2024, the U.S. Environmental Protection Agency (EPA) announced the first-ever legally enforceable drinking water standards for per- and polyfluoroalkyl substances (PFAS). PFAS are a group of thousands of manmade chemicals that have been manufactured and used globally since the 1940s. They are commonly found in textiles, cookware, packaging, plastics, and firefighting foams. PFAS are typically very persistent in the environment and in the human body, meaning that they do not break down and can accumulate over long periods of time. For that reason, they are often called “forever chemicals.” This action is the most recent step in the EPA’s October 2021 “PFAS Strategic Roadmap,” a report establishing action items to address PFAS contamination and timelines for their completion.

Under the Safe Drinking Water Act, the EPA has the authority to regulate drinking water contaminants in public water systems through enforceable National Primary Drinking Water Regulations (NPDWRs) and monitoring requirements. The new NPDWR sets maximum contaminant levels (MCLs) for five individual PFAS: PFOA, PFOS, PFNA, PFHxS, and HFPO-DA (also known as GenX Chemicals). In addition, the EPA established limits for PFAS mixtures containing at least two or more of PFHxS, PFNA, HFPO-DA, and PFBS using a Hazard Index MCL.

Public water systems have three years to complete their initial monitoring for these PFAS and must inform the public of the level of PFAS measured in their drinking water. Where PFAS levels exceed the MCLs, systems must implement solutions to reduce PFAS in their drinking water within five years. The new standards are expected to impose billions of dollars in additional costs on local water utilities across the U.S.

The enforceable PFAS MCLs establish a standard for PFAS in drinking water that may be, and already has been, used in litigation targeting PFAS manufacturers. On April 15, 2024, California water utilities filed a lawsuit against seven PFAS manufacturers alleging negligence and nuisance and citing exceedances of the new NPDWR standards.

A pre-publication of the PFAS NPDWR is available here.

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