November 28, 2022

Volume XII, Number 332


EPA’s New Drinking Water Health Advisories for PFAS Chemicals

Yesterday, US Environmental Protection Agency (EPA) announced far more stringent drinking water health advisories for per- and polyfluoroalkyl substances (PFAS).

We previously blogged on this topic here and here.

Under the Safe Drinking Water Act, EPA may publish health advisories for contaminants that are not subject to any national primary drinking water regulation. These health advisories are intended to provide technical information that federal, state, and local agencies can use to inform actions to address PFAS in drinking water, including water quality monitoring, optimization of existing technologies that reduce PFAS, and strategies to reduce exposure to these substances. The advisories are not enforceable by federal law.

The new advisories are interim and apply to four PFAS, including perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), final health advisories for hexafluoropropylene oxide (HFPO) dimer acid and its ammonium salt (together referred to as “GenX chemicals”), and perfluororbutane sulfonic acid and its related compound potassium perfluororbutane sulfonate (together referred to as “PFBS”). The advisories are “interim” in that they are meant to be in place until EPA’s issuance of a National Primary Drinking Water Regulation for PFAS. A proposed version of that regulation is expected later this year.

The health advisories, which identify the concentration of chemicals in drinking water at or below the level at which adverse health effects are not anticipated to occur, are:

  • 0.004 parts per trillion (ppt) for PFOA;

  • 0.02 ppt for PFOS;

  • 10 ppt for GenX chemicals; and

  • 2,000 ppt for PFBS

Among other stakeholders, the American Chemistry Council responded to the new interim advisories by pointing out that these levels are below current reliable testing and treatment capabilities and that the underlying supporting reports are subject to ongoing review by EPA’s Science Advisory Board.

Prior PFAS Heath Advisories

The interim health advisories replace EPA 2016 final health advisories for PFOA and PFOS, which were both set at 70 ppt. As noted by the American Chemistry Council, the studies underlying the new advisories are currently undergoing EPA Science Advisory Board review. EPA has explained that it is proceeding with the new advisories regardless due to its concern about the public health implications of its preliminary findings regarding these chemicals.

GenX Chemicals and PFBS

This is the first time EPA has issued health advisories for these chemicals. (GenX chemicals are often considered as replacements for PFOA, and PFBS is often considered a replacement for PFOS.)

Next Steps

EPA plans on proposing a PFAS National Drinking Water Regulation this fall. These advisories are intended to provide guidance for the period prior to that regulation going into effect.

© 2022 ArentFox Schiff LLPNational Law Review, Volume XII, Number 167

About this Author

Daniel Deeb Civil Litigation Attorney Schiff Hardin

Dan has been practicing environmental law for more than 20 years. His practice includes all facets of environmental law permitting, compliance and litigation, including federal and state cases involving the Clean Water Act, Clean Air Act, RCRA, CERCLA, FIFRA, TSCA, brownfields redevelopment, and state analogs. Before practicing law, Dan worked as a senior chemist for an environmental consulting firm and clerked for the U.S. EPA’s Office of Enforcement and Compliance Assurance. He is a frequent lecturer and has written about environmental legal issues for a variety of publications. His...


Sara A. McQuillen is an associate with Schiff Hardin in Washington. She is only admitted to the TX Bar, however is practicing under the supervision of partners in the District of Columbia offices. 


  • University of Notre Dame Law School, J.D., 2017, cum laude
    Journal of Legislation, Executive Notes Editor
    Dean’s List
    Best Brief Award, Legal Reseach and Writing II
  • University of Texas at Austin, B.A., 2014, magna cum laude
20- 724- 6837