Makers of PFAS ‘Forever Chemicals’ Covered Up Health Risks, Secret Industry Documents Reveal

Makers of PFAS (per and polyfluoroalkyl substances) “forever chemicals” have a lot to hide. Exposure to the toxic compounds — found in everything from nonstick cookware and personal care products, like shampoo and dental floss, to waterproof rain gear — has been shown to cause cancer, thyroid disease, liver damage and fertility issues.

Recently, previously secret chemical industry documents were analyzed by researchers from the University of California San Francisco (UCSF). They found that chemical manufacturers had used tactics previously employed by the tobacco industry to suppress their knowledge of the health hazards caused by PFAS exposure, a press release from UCSF said.

“These documents reveal clear evidence that the chemical industry knew about the dangers of PFAS and failed to let the public, regulators, and even their own employees know the risks,” said Tracey J. Woodruff, Ph.D., professor and director of the UCSF Program on Reproductive Health and the Environment (PRHE), who is also a former policy advisor and senior scientist at the U.S. Environmental Protection Agency (EPA) and senior author of the paper, in the press release.

The paper, “The Devil they Knew: Chemical Documents Analysis of Industry Influence on PFAS Science,” was published in the journal Annals of Global Health.

The researchers examined documents from 3M and DuPont, the largest PFAS manufacturers, and analyzed their tactics in delaying public awareness of the toxicity of PFAS, as well as regulations governing the use of the dangerous chemicals.

The analysis of the PFAS industry documents is the first by scientists to use methods devised to expose tobacco industry strategies.

In analyzing similar documents from cigarette manufacturers, the researchers used scientific methods developed by researcher for the tobacco industry Stan Glantz, reported The Guardian. They found that producers of PFAS and their cohorts often used two strategies favored by tobacco companies: twisting public discourse and hiding internal studies that showed health impacts.

“All these companies… try to prevent the development of public understanding and they’re always years ahead of the public and mainstream scientific community,” Glantz said, as The Guardian reported.

PFAS are extremely resistant to breaking down and have since become omnipresent in people’s bodies and the environment, but their manufacturers had been aware of their dangerous effects for decades.

“DuPont had evidence of PFAS toxicity from internal animal and occupational studies that they did not publish in the scientific literature and failed to report their findings to EPA as required under TSCA. These documents were all marked as ‘confidential,’ and in some cases, industry executives are explicit that they ‘wanted this memo destroyed,’” the paper states.

The hidden industry documents were found when a lawsuit was filed by attorney Robert Bilott. Bilott successfully sued DuPont for PFAS contamination for the first time. The film Dark Waters featured the story, and Bilott gave the 45 years worth of documents — from 1961 to 2006 — to the producers of documentary The Devil We Know. They, in turn, gave the documents to the Chemical Industry Documents Library at UCSF.

“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,” said first author of the report Nadia Gaber, MD, Ph.D., who led the research as a PRHE fellow, in the press release. “This research is important to inform policy and move us towards a precautionary rather than reactionary principle of chemical regulation.”

In the paper, the authors state that, for the first 50 years PFAS were in use, not much was known publicly about their toxicity. This was notwithstanding the fact that “industry had multiple studies showing adverse health effects at least 21 years before they were reported in public findings.”

A timeline of the knowledge the industry had versus what the public knew is documented in the paper, with an analysis of the chemical industry’s strategies for suppressing the information or protecting their dangerous products.

One example is the documentation of cases of enlarged organs in a company report as early as 1961. The Chief of Toxicology at Teflon discovered that the chemicals used in the product had “the ability to increase the size of the liver of rats at low doses,” and recommended that they “be handled ‘with extreme care’ and that ‘contact with the skin should be strictly avoided.’”

Additionally, an internal memo from DuPont-funded Haskell Laboratory in 1970 found one PFAS, C8, to be “highly toxic when inhaled and moderately toxic when ingested.”

And, in 1980, 3M and DuPont learned that two out of eight employees who were pregnant while working in C8 manufacturing had given birth to children who had birth defects. The company didn’t tell employees or publish the information, and an internal memo the next year said, “We know of no evidence of birth defects caused by C-8 at DuPont.”

Not only that, but despite these and other examples, employees were told in 1980 that C8 “has a lower toxicity, like table salt.”

Following reports of groundwater contaminated with PFAS near a DuPont manufacturing plant, a press release from 1991 made the claim that, “C-8 has no known toxic or ill health effects in humans at concentration levels detected.”

When lawsuits in 1998 and 2002 garnered more media attention, an email from DuPont to the EPA said, “We need EPA to quickly (like first thing tomorrow) say the following: That consumer products sold under the Teflon brand are safe and to date there are no human health effects known to be caused by PFOA [Perfluorooctanoic acid].”

The EPA fined DuPont in 2004 for not revealing their PFOA findings. At the time, the settlement of $16.45 million — a small portion of the company’s $1 billion yearly profits from C8 and PFOA in 2005 — was the biggest civil penalty under U.S. environmental laws.

“As many countries pursue legal and legislative action to curb PFAS production, we hope they are aided by the timeline of evidence presented in this paper,” Woodruff said in the press release. “This timeline reveals serious failures in the way the U.S. currently regulates harmful chemicals.”