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GenX Toxicity Assessments Documents

In November 2020, EPA announced the availability of the final Toxicity Assessment for Perfluorobutane Sulfonic Acid (CASRN 375-73-5) and Related Compound Potassium Perfluorobutane Sulfonate (CASRN 29420-49-3) and the Toxicity Assessment: 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.

In addition, you will find the publicly released draft materials from November 2018, including: the draft toxicity reports, public comment documents, EPA's response to comment's document, and supporting communication materials.

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