Perfluorohexanoic acid (PFHxA) is a

fluorinated In chemistry, halogenation is a chemical reaction which introduces one or more halogens into a chemical compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. ...

carboxylic acid In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an Substituent, R-group. The general formula of a carboxylic acid is often written as or , sometimes as with R referring to an organyl ...

derivative of

hexanoic acid Caproic acid, also known as hexanoic acid, is the carboxylic acid derived from hexane with the chemical formula . It is a colorless oily liquid with a fatty, cheesy, waxy odor resembling that of goats or other barnyard animals. It is a fatty acid ...

. Fluorinated polymers with six

carbon Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 ...

or less commonly degrade into perfluorohexanoic acid. Perfluorohexanoic acid does not seem to persistently bioaccumulate in the manner of many other

PFAS Per- and polyfluoroalkyl substances (also PFAS, PFASs, and informally referred to as "forever chemicals") are a group of synthetic organofluorine chemical compounds that have multiple fluorine atoms attached to an alkyl chain; there are 7 millio ...

. For example, in a study sponsored by the Swedish EPA, Swedish

ski wax Ski wax is a material applied to the bottom of snow runners, including skis, snowboards, and toboggans, to improve their coefficient of friction performance under varying snow conditions. The two main types of wax used on skis are glide waxes and ...

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 Perfluorooctanoic acid (PFOA; conjugate base perfluorooctanoate; also known colloquially as C8, from its chemical formula C8HF15O2) is a perfluorinated carboxylic acid produced and used worldwide as an industrial surfactant in chemical process ...

, up to 44 times higher than the general population. In 2020

Michigan Michigan ( ) is a peninsular U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest, Upper Midwestern United States. It shares water and land boundaries with Minnesota to the northwest, Wisconsin to the west, ...

adopted drinking water standards for five previously unregulated PFAS compounds including PFHxA which has a

maximum contaminant level Maximum contaminant levels (MCLs) are standards that are set by the United States Environmental Protection Agency (EPA) for drinking water quality.Joseph Cotruvo, Victor Kimm, Arden Calvert“Drinking Water: A Half Century of Progress.”EPA Alumn ...

(MCL) of 400 parts per billion ( ppb). Its placing on the market and use will be restricted in the

EEA The European Economic Area (EEA) was established via the ''Agreement on the European Economic Area'', an international agreement which enables the extension of the European Union's single market to member states of the European Free Trade Assoc ...

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
/ref>

References

Chemistry timelines Perfluorocarboxylic acids