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Drinking Water Health Advisories for GenX Chemicals and PFBS

Related Information

  • General Information about PFOA, PFOS and Other PFAS
  • Interim Updated Drinking Water Advisories for PFOA and PFOS
  • General Information about Health Advisories
  • PFOA and PFOS UCMR data
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2022 Final Health Advisories for GenX Chemicals and PFBS

On June 15, 2022, EPA issued final health advisories (HAs) for these two per- and polyfluoroalkyl substances (PFAS): 1) hexafluoropropylene oxide (HFPO) dimer acid and its ammonium salt (referred to as “GenX chemicals"); and 2) perfluorobutane sulfonic acid and its potassium salt (PFBS).

In chemical and product manufacturing, GenX chemicals are considered a replacement for perfluorooctanoic acid (PFOA), and PFBS is considered a replacement for perfluorooctane sulfonic acid (PFOS).

At the same time, EPA issued interim updated drinking water health advisories for PFOA and PFOS that replace those EPA issued in 2016. These updated health advisories levels, which are based on new science, will remain in place until EPA establishes a National Primary Drinking Water Regulation.

Basic Information

  • Press Release (June 15, 2022)
  • Federal Register Notice on Lifetime Drinking Water Health Advisories for Four Perfluoroalkyl Substances (June 21, 2022)
  • Drinking Water Health Advisories for PFAS Fact Sheet for Communities (PFOA, PFOS, GenX Chemicals and PFBS) (pdf)
    • Spanish version (coming soon!)
  • Questions and Answers: HAs for PFOA, PFOS, GenX Chemicals and PFBS
    • Spanish version (coming soon!)
  • Drinking Water Health Advisories for PFAS Fact Sheet for Public Water Systems (PFOA, PFOS, GenX Chemicals and PFBS) (pdf)

Technical Information

  • Technical Fact Sheet: Drinking Water Health Advisories for Four PFAS (PFOA, PFOS, GenX Chemicals, and PFBS) (pdf) (June 2022, EPA 822-F-22-002)
  • Drinking Water Health Advisory: Hexafluoropropylene Oxide (HFPO) Dimer Acid (CASRN 13252-13-6) and HFPO Dimer Acid Ammonium Salt (CASRN 62037-80-3), Also Known as “GenX Chemicals” (pdf) (June 2022, EPA 822-R-22-005)
    • Final Human Health Toxicity Values for Hexafluoropropylene Oxide (HFPO) Dimer Acid and Its Ammonium Salt (CASRN 13252-13-6 and CASRN 62037-80-3) Also Known As “GenX Chemicals” (pdf) (October 2021)
  • Drinking Water Health Advisory: Perfluorobutane Sulfonic Acid (CASRN 375-73-5) and Related Compound Potassium Perfluorobutane Sulfonate (CASRN 29420-49-3) (pdf) (June 2022, EPA 822-R-22-006)
    • Human Health Toxicity Values for Perfluorobutane Sulfonic Acid (CASRN 375-73-5) and Related Compound Potassium Perfluorobutane Sulfonate (CASRN 29420-49-3)
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on June 21, 2022
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