Per- and polyfluoroalkyl substances

Per- and polyfluoroalkyl substances (PFAS^[1] or PFASs^[2]) are a group of synthetic organofluorine chemical compounds that have multiple fluorine atoms attached to an alkyl chain; there are 7 million such chemicals according to PubChem.^[3] PFAS came into use after the invention of Teflon in 1938 to make fluoropolymer coatings and products that resist heat, oil, stains, grease, and water. They are now used in products including waterproof fabric such as Nylon, yoga pants, carpets, shampoo, feminine hygiene products, mobile phone screens, wall paint, furniture, adhesives, food packaging, heat-resistant non-stick cooking surfaces such as Teflon,^[4] firefighting foam, and the insulation of electrical wire.^[5][6][7] PFAS are also used by the cosmetic industry in most cosmetics and personal care products, including lipstick, eye liner, mascara, foundation, concealer, lip balm, blush, and nail polish.^[8][9]

Many PFAS such as PFOS and PFOA pose health and environmental concerns because they are persistent organic pollutants or "forever chemicals"; they have half-lives of up to over 8 years due to a carbon-fluorine bond, one of the strongest in organic chemistry.^{[10][11][12][13][14][15]} They move through soils and bioaccumulate in fish and wildlife, which are then eaten by humans. Residues are now commonly found in rain and drinking water.^{[10][16][17][6]} Since PFAS compounds are highly mobile, they are readily absorbed through human skin and through tear ducts, and such products on lips are often unwittingly ingested.^[18] Due to the large number of PFAS, it is challenging to study and assess the potential human health and environmental risks; more research is necessary and is ongoing.^{[19][10][20][5]}

Exposure to PFAS, some of which have been classified as carcinogenic, has been linked to cancers such as kidney, prostate and testicular cancer, ulcerative colitis, thyroid disease, suboptimal antibody response / decreased immunity, decreased fertility, reduced infant and fetal growth and developmental issues in children, obesity, dyslipidemia (abnormally high cholesterol), and higher rates of hormone interference.^[5][21][22]

The use of PFAS has been regulated internationally by the Stockholm Convention on Persistent Organic Pollutants since 2009, with some jurisdictions, such as China and the European Union planning further reductions and phase-outs. However, major producers and users such as the United States, Israel, and Malaysia have not ratified the agreement and the chemical industry has lobbied governments to reduce regulations^[23] or has moved production to countries such as Thailand, where there is less regulation.^[24][25] In the United States, the Republican Party has filibustered bills regulating the chemicals.^[23] Cover-ups and the suppression of studies in 2018 by the Trump administration led to bipartisan outrage.^[26][27]

The market for PFAS was estimated to be $28 billion in 2023 and the majority are produced by 12 companies: 3M, AGC Inc., Archroma, Arkema, BASF, Bayer, Chemours, Daikin, Honeywell, Merck Group, Shandong Dongyue Chemical, and Solvay.^[28] Sales of PFAS, which cost approximately $20 per kilogram, generate a total industry profit of $4 billion per year on 16% profit margins.^[29] Due to health concerns, several companies have ended or plan to end the sale of PFAS or products that contain them; these include W. L. Gore & Associates (the maker of Gore-Tex), H&M, Patagonia, REI, and 3M.^{[30][31][32][33][34][35]} PFAS producers have paid billions of dollars to settle litigation claims, the largest being a $10.3 billion settlement paid by 3M for water contamination in 2023.^[36] Studies have shown that companies have known of the health dangers – DuPont and 3M were aware that PFAS was "highly toxic when inhaled and moderately toxic when ingested" since the 1970s.^[37] Externality, including remediation of PFAS from soil and water contamination, the cost of treating related diseases, and monitoring of PFAS pollution may cost as much as US$17.5 trillion annually, according to ChemSec.^[29] The Nordic Council of Ministers estimated health costs to be at least €52–84 billion in the European Economic Area.^[38] In the United States, PFAS-attributable disease costs are estimated to be US$6–62 billion.^[39][40]