However, PFHxS is an unusual exception in that its half-life is greater than both longer and shorter chain equivalents such as PFOS or PFBS.

[10] Data from the 2003-2004 National Health and Nutrition Examination Survey in the United States found the average serum concentration of PFHxS in the general US population to be 1.9 μg/L, with the 10th and 90th percentiles being 0.7 and 8.3 μg/L, respectively.

This reflects the relative lack of epidemiological and toxicological information on the human health effects of exposure to PFHxS.

[4] PFHxS, its salts and related compounds have been recommended to be added to Annex A of the United Nations Stockholm Convention on Persistent Organic Pollutants.

[16] Upon entry into force, nations party to the convention are legally bound to take act to cease production and use of PFHxS.

[17] Food Standards Australia New Zealand found insufficient evidence to justify a tolerable daily intake (TDI) for PFHxS specifically.

[19] The Danish EPA has established a drinking water and groundwater limit value of 2 ng/L for the sum of 4 PFASs; , PFHxS, PFOS, PFOA, and perfluorononanoic acid (PFNA).

[20] The Swedish National Food Agency recommends a drinking water limit of 0.09 μg/L for the sum of 11 PFASs (PFBS, PFHxS, PFOS, 6:2 FTSA, PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFNA and PFDA).

The United States Environmental Protection Agency (EPA) is developing toxicity values for PFHxS, as well as PFBA, PFHxA, PFNA and PFDA.

[4] In 2020, Michigan adopted drinking water standards for 5 previously unregulated PFASs including PFHxS, which has a maximum contaminant level (MCL) of 51 parts per trillion (ppt) or 0.051 μg/L.