Per- and polyfluoroalkyl substances (PFAS) are a large family of man-made, globally-distributed chemicals. They include perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). PFAS have been widely used in consumer products such as non-stick cookware, carpets and carpet treatment products, food packaging, aqueous firefighting foams, and in the aerospace, automotive, construction, and electronics industries.
Once released into the environment, some PFAS are not easily broken down when exposed to air, water, or sunlight. Thus people can be exposed to PFAS that were manufactured months or years in the past. PFAS can travel long distances in the air and water with the result that people may be exposed to PFAS manufactured or emitted from production facilities many miles away from the point of exposure. Human exposure can also occur through contact with products containing PFAS.
A recent study of the effectiveness of currently-used treatment technologies for removal of PFAS from raw water or potable reuse sources found that granular activated carbon and anion exchange can under certain conditions treat long-chain PFAS and that costly nanofiltration and reverse osmosis could potentially treat most PFAS.