PFOSA can be synthesized from perfluorooctanesulfonyl halides by reaction with liquid ammonia[5] or by a two step reaction via an azide followed by reduction with Zn and HCl.[6] PFOSA is also a metabolic by-product of N-alkylated perfluorooctanesulfonamides.[5] For example, N-ethyl perfluorooctanesulfonamidoethanol (N-EtFOSE), which was primarily used on paper,[7]
and N-methyl perfluorooctanesulfonamidoethanol (N-MeFOSE), which was primarily used on carpets and textiles, both metabolize via acetates to PFOSA.[8]
Wildlife biomonitoring studies have found the highest level of PFOSA in the liver of common dolphin (Mediterranean Sea, Italy) with a concentration of 878 parts per billion; the liver of mink from Illinois, US, contained 590 parts per billion.[14] In fish, the highest levels detected were in the liver of Norway Pike (91 parts per billion) and homogenates of slimy sculpin (150 parts per billion) from Lake Ontario.[14] Differences in biotransformation across species could explain some of its presence.[14] In humans, PFOSA has been detected in sub- to low-parts per billion levels;[14] for example, in 1999–2000 US serum samples, the 95th percentile (or value where only 5% of the population was higher) was 1.4 parts per billion[15] while in 2003–2004 the 95th percentile fell to 0.2 parts per billion.[16] However, whole-blood concentrations are about five times higher than those in blood plasma or serum.[17]
^Boulanger B, Vargo JD, Schnoor JL, Hornbuckle KC (August 2005). "Evaluation of perfluorooctane surfactants in a wastewater treatment system and in a commercial surface protection product". Environ. Sci. Technol. 39 (15): 5524–30. Bibcode:2005EnST...39.5524B. doi:10.1021/es050213u. PMID16124283. Supporting Information (PDF).
^Fromme H, Tittlemier SA, Völkel W, Wilhelm M, Twardella D (May 2009). "Perfluorinated compounds – Exposure assessment for the general population in western countries". Int. J. Hyg. Environ. Health. 212 (3): 239–70. doi:10.1016/j.ijheh.2008.04.007. PMID18565792.
^Olsen GW, Church TR, Larson EB, van Belle G, Lundberg JK, Hansen KJ, Burris JM, Mandel JH, Zobel LR (March 2004). "Serum concentrations of perfluorooctanesulfonate and other fluorochemicals in an elderly population from Seattle, Washington". Chemosphere. 54 (11): 1599–611. Bibcode:2004Chmsp..54.1599O. doi:10.1016/j.chemosphere.2003.09.025. PMID14675839.
^Grossman MR, Mispagel ME, Bowen JM (December 1992). "Distribution and tissue elimination in rats during and after prolonged dietary exposure to a highly fluorinated sulfonamide pesticide". J. Agric. Food Chem. 40 (12): 2505–9. doi:10.1021/jf00024a033.