1-Octanesulfonic acid, 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluoro-, ammonium salt

Made and used for oil- and water‑repellent products, metal plating, semiconductor processing, and older firefighting foams (AFFF); can contaminate soil, water, and waste streams [1][2].

Drinking contaminated water (common near airports, military bases, or fluorochemical plants), eating contaminated fish/food, breathing household dust, and some workplaces; it can pass during pregnancy and into breast milk [1][3].

PFOS accumulates in people. Studies link exposure with higher cholesterol, reduced vaccine response, liver and thyroid changes, pregnancy-induced hypertension, and developmental effects; EPA set very low drinking water standards due to these risks [1][2][3].

Workers using AFFF or PFAS, people on contaminated private wells, and pregnant people, infants, and children [1][3].

Check local PFAS water results; use NSF/ANSI 53 or 58 certified filters; follow fish and foam-use advisories; wet-dust and HEPA vacuum; avoid optional stain‑resistant treatments [2][3].