Manufacturers of ‘Forever Chemicals’ Knew of Health Risks, Secret Documents Reveal

Secretly held documents from DuPont and 3M, two of the most prominent manufacturers of ‘forever chemicals,’ reveal that company leaders knew of the harmful health effects of some per- and poly-fluoroalkyl substances (PFAS) long before they informed the public. In internal research, two of their most popular chemicals, called PFOS and PFOA, were found to have all sorts of adverse health effects that government officials were not made aware of. These documents, spanning 1961 to 2006, were initially obtained by attorney Robert Bilott in the early 2000s when he sued DuPont for PFAS contamination successfully. Recently, these documents were donated to researchers at the University of California, San Francisco (UCSF), by the producers of a 2018 investigative documentary on DuPont.

PFAS Chemicals Pose Health Risks

PFAS chemicals are known as ‘forever chemicals’ because they take ages to break down in the environment. They have been used since the 1940s in non-stick cookware, fabric treatment, cosmetics, and food packaging. Of the more than 12,000 known PFAS variants available today, two clearly show adverse health outcomes, including increased risks of cancer and birth defects. In the early 2000s, PFOA and PFOS were phased out of production in the US, but by then, they had already spread far and wide. Even at minor traces, these chemicals can cause adverse health effects. Over 90% of pregnant people in the US continue to be exposed to these potentially harmful chemicals.

Deceptive Industry Tactics and Chemical Regulations

At first, both DuPont and 3M claimed that PFAS chemicals were biologically inert. However, investigative reporting and legal disclosures show that industry leaders knew this wasn’t true for many years. Internal documents from the 1970s show that DuPont knew that PFOA was “highly toxic” when inhaled and “moderately toxic” when ingested. As far back as 1961, documents show that Teflon’s Chief of Toxicology knew PFOA had “the ability to increase the size of the liver of rats at low doses” and should “be handled ‘with extreme care’ and that ‘contact with the skin should be strictly avoided.’” It took 30 years after industry knowledge for the first peer-reviewed papers to connect birth defects to PFAS in the scientific literature.

Today, chemical regulations in the US are usually made in hindsight, putting public health at risk. Novel materials are manufactured first and tested for toxicity only after they appear on the market. The harms of this approach are more than evident when looking at the history of ‘forever chemicals.’ No federal enforceable limits on any PFAS chemicals have been established in the US, and researchers at UCSF point out that “having access to these documents allows us to see what the manufacturers knew and when, but also how polluting industries keep critical public health information private. This research is important to inform policy and move us towards a precautionary rather than reactionary principle of chemical regulation.”

The deceptive tactics used by DuPont and 3M to suppress research and influence government regulations are reminiscent of those employed by tobacco companies, researchers say. If something does not change, history could easily keep repeating itself.