Makers of PFAS, a class of chemicals used in everything from cookware to food containers and makeup, had evidence the substances were toxic as early as the 1970s and obscured the danger, according to a new study based on industry archives held at the University of California.
Governments in Canada and the U.S. are now cracking down on per- and polyfluoroalkyl substances (PFAS), a class of more than 9,000 human-made chemicals produced since the 1940s. They have unique properties that make them heat-resistant, oil- and water-repellent and friction-resistant, and are found in products from cosmetics and take-out boxes to non-stick cookware and fire suppressants.
PFAS are sometimes called