Since the 1940s, companies have been using PFAS – perfluoroalkyl and polyfluoroalkyl substances – to make products easier to use, from Teflon nonstick pots to waterproof rain gear, stain-resistant carpet and firefighting foam.
The chemicals’ resistance to heat, oils, stains, grease and water makes them useful. However, that same chemical stability also makes them linger in the environment – and in the human body. Studies have suggested that some types of PFAS can contribute to health harms, including thyroid disease, liver damage and kidney and testicular cancer.
The U.S. Environmental Protection Agency has concluded that there is no safe level of human exposure for two of the most common PFAS compounds: perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). It set drinking water standards limiting their acceptable levels in water systems in 2024.
