EPA Releases Draft IRIS Assessment of PFHxS and Related Salts

On July 24, 2023, EPA released a draft IRIS Toxicological Review of Perfluorohexanesulfonic Acid (PFHxS) and Related Salts.  Comments on the draft assessment will be accepted through September 22, 2023.

The IRIS assessment found that, given sufficient exposure conditions, PFHxS is likely to cause thyroid and developmental immune effects in humans.  Other evidence suggests but is insufficient to infer that PFHxS exposure might cause teratological, hepatic, neurodevelopmental, and cardiometabolic effects in humans.  EPA concluded that there is inadequate information to assess whether PFHxS exposure can result in hematopoietic, reproductive, renal, and carcinogenic effects.

PFHxS is one of three PFAS currently undergoing IRIS assessments, along with PFNA and PFDA.  EPA previously published final IRIS assessments for two other PFAS: PFBA in December 2022 and PFHxA in April 2023.