In 2023, it’s hard to get away from breaking news about PFAS, a class of more than 12,000 chemicals used in countless products from nonstick pans to cosmetics to food packaging. These so-called forever chemicals have been linked to a host of physical ills, including increased risk of certain cancers, high cholesterol, hormonal disruption, immune-system problems, decreased fertility, and developmental delays in children.
PFAS, first developed in the 1940s, weren’t always so well known by people outside of the industries manufacturing them. But a new study analyzing industry documents published reveals just how much and how early the two biggest manufacturers of the chemicals—3M and DuPont—knew about the potential harms the products posed. As the researchers found, and knew broadly about the dangers the chemicals pose by 1970—two decades before the public really became aware of the chemicals’ health risks.