Replacement chemical in Teflon causing cancer in lab rats - report
GenX was the replacement for perfluorooctanoic acid (PFOA), a long-chain perfluorinated chemical previously used in Teflon products.
DuPont shelved PFOA in 2009, following a class-action lawsuit regarding health hazards associated with the chemical. The US Environmental Protection Agency (EPA) has worked to investigate and even discourage the use of PFOA, also known as C8, but has not determined that it "poses an unreasonable risk to the public."
Meanwhile, DuPont has moved on, replacing PFOA/C8 with GenX to make its popular Teflon cookware and hundreds of other products. DuPont has characterized GenX as safer than PFOA, saying the former has a "more favorable toxicological profile" than PFOA/C8.
The names/structures of potentially toxic chemicals can be withheld from the public and all but a few EPA officials. https://t.co/eVzvNGS2cr— The Intercept (@the_intercept) March 3, 2016
Reports accessed by The Intercept were filed with the EPA between 2006 and 2013 under Section 8 (e) of the Toxic Substances Control Act. That section of the 1976 law requires an entity involved in the manufacture or dissemination of a chemical substance or mixture that has information that "reasonably supports the conclusion" that the substance "presents a substantial risk of injury to health or the environment" must inform the EPA.
The documents say GenX has been associated with deleterious health effects in test animals, including cancer, weight gain, changes to the immune system and cholesterol levels, fluctuations in the size of kidneys and livers, and problems related to reproduction.
In January 2013, a DuPont report stated that rats exposed to varying amounts of GenX over a two-year period formed cancerous tumors in the liver, pancreas, and testicles. Rats also developed benign tumors, kidney disease, liver failing, and uterine polyps, The Intercept reported.
The company scientist that signed the report downplayed the significance of these conditions in relation to humans, writing “these tumor findings are not considered relevant for human risk assessment.” DuPont scientists had previously made similar claims about C8/PFOA.
“It’s the same constellation of effects you see with PFOA,” said Deborah Rice, a retired toxicologist and risk assessor for the EPA's National Center for Environmental Assessment. “There’s no way you can call this a safe substitute.”
Alan Ducatman, an environmental health sciences professor at the West Virginia University School of Public Health, told The Intercept that DuPont engages in "cherry picking" of its own data regarding health effects on animals versus humans. The company, he said, points out "species differences only when arguing that a problematic study finding is not relevant.”
Ducatman noted that GenX is similar to C8/PFOA and like-chemicals in that it has damning effects on the liver, immune system, and how the body processes fats.
“This reminds me a lot of a path we have recently traveled," he said. "That journey is not ending well.”
Another of DuPont's C8/PFOA studies submitted to the EPA found that male rats given any amount of GenX experienced changes in cholesterol levels, among other issues. Yet the company said “these changes were of uncertain relationship to treatment and considered non-adverse.”
Other reports found that lab animals given GenX were more likely to give premature birth and to deliver babies that weighed less than rats not given GenX. Delayed puberty was another effect on GenX-exposed animals. Yet those reports describe only the effects of large doses of GenX, which is an incomplete snapshot of the chemical's capabilities, according to Laura Vandenberg, a reproductive biologist at the University of Massachusetts, Amherst.
“That might make sense if what we were worried about was whether this chemical maims or kills you outright,” Vandenberg told The Intercept. “But that’s not what we’re seeing. People don’t cook on Teflon and drop dead. These are chemicals that interfere with normal biological functions at low doses and contribute to disease.” Hormones act at low doses, she said. Thus, “you have to study them at low doses.”
Despite clear warnings about GenX represented in the DuPont reports, one EPA official said there is no guarantee the agency will act. “A lot of them do just get filed away,” said Vincent Cogliano, director of the Integrated Risk Information System at the EPA. An attempt to add GenX to a list of substances monitored in drinking water will certainly be met with resistance, he said.
“Companies fight them and bring in other scientists who debunk the studies that show there are health hazards," Cogliano said.
DuPont would not comment to The Intercept, saying GenX is now produced by Chemours, described as a "spin-off of the DuPont Performance Chemicals unit."
Of GenX, Chemours said that the "full body of testing data indicates that the polymerization aid can be used safely in the manufacture of fluoropolymers. It is rapidly eliminated from the body with low bioaccumulation potential. … Regulatory authorities in the US, Europe, China, Japan and Taiwan have reviewed the testing data on our new polymerization aid and have given permission for its manufacture and use."
In October 2015, an Ohio woman was awarded $1.6 million after a jury found that PFOA leaked from a DuPont plant into drinking water supplies, contributing to her kidney cancer.