Perfluorohexanoic acid (PFHxA) is a perfluorocarboxylic acid derivative of hexanoic acid. Side-chain fluorinated polymers and fluorotelomer compounds with five carbon atoms or more commonly degrade into perfluorohexanoic acid.
Perfluorohexanoic acid does not seem to persistently bioaccumulate in the manner of many other PFAS. For example, in a study sponsored by the Swedish EPA, Swedish ski wax technicians, who have high PFAS exposure, did not have significantly higher levels of PFHxA in their blood samples when compared to the general population median for their age groups, even while having concentrations of other PFAS, like PFOA, up to 44 times higher than the general population.
In 2020 Michigan adopted drinking water standards for five previously unregulated PFAS compounds including PFHxA which has a maximum contaminant level (MCL) of 400 parts per billion (ppb).
Its placing on the market and use will be restricted in the EEA and Switzerland by 2026.Commission Regulation (EU) 2024/2462 of 19 September 2024 amending Annex XVII to Regulation (EC) No 1907/2006 of the European Parliament and of the Council as regards undecafluorohexanoic acid (PFHxA), its salts and PFHxA-related substances
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