‘Forever chemicals’: what are PFAS and what risk do they pose?
They have useful properties, but some have been banned and toxicity of others is unknown
PFAS are a family of thousands of human-made substances – nicknamed “forever chemicals” because they do not break down in the environment – that have been widely used since the 1940s in a huge range of everyday consumer products and industrial processes.
Valued for their nonstick and stain-repellent properties, they can be found in food packaging, cosmetics, cookware, waterproof clothing, carpets, mattresses, electronics and fire-fighting foams. In industry, they are used in processes such as metal finishing and plating, hydraulic fluids and semiconductor manufacturing.
Uses of just two of the substances – PFOS and PFOA – have been banned or restricted because of their toxic, persistent and bioaccumulative effects, but there are concerns about others on which there is less toxicity evidence available because they have been less studied.
The chemicals have a relatively low profile in the UK, but in the US PFAS has become a household term. The devastating impacts of PFOA was first exposed by US lawyer Rob Bilott who has been fighting for decades on behalf of people exposed to the chemicals. His David and Goliath struggle to prove that DuPont, which was using PFOA in the manufacture of Teflon, had poisoned drinking water with PFOA, and that PFOA manufacturers had long known about its toxic effects, was portrayed by Mark Ruffalo in the 2019 film Dark Waters.
Related: PFAS ‘forever chemicals’ constantly cycle through ground, air and water, study finds
Bilott’s work led to an enormous epidemiological study of 69,000 people, which linked PFOA to a range of diseases, including kidney and testicular cancer. His class actions have led to settlements of about $753m to date and have spawned similar legal cases across the world, including in Australia where PFOS from firefighting foam used at defence bases has made it into water used by a number of towns.
No longer able to ignore the issue, in the US, the Environmental Protection Agency has created a list of more than 120,000 locations where people may be exposed to PFAS.
In Europe, Germany, Denmark, the Netherlands, Norway and Sweden have signalled their intention to ban the manufacture of PFAS, most of their uses and their placement on the EU market.
