Chemical giants DuPont and Daikin knew the dangers of a PFAS compound widely used in food packaging since 2010, but hid them from the public and the Food and Drug Administration (FDA), company studies obtained by the Guardian reveal. The chemicals, called 6:2 FTOH, are now linked to a range of serious health issues, and Americans are still being exposed to them in greaseproof pizza boxes, carryout containers, fast-food wrappers, and paperboard packaging. The companies initially told the FDA that the compounds were safer and less likely to accumulate in humans than older types of PFAS, also known as “forever chemicals” and submitted internal studies to support that claim. But Daikin withheld a 2009 study that indicated toxicity to lab rats’ livers and kidneys, while DuPont in 2012 did not alert the FDA or public to new internal data that indicated that the chemical stays in animals’ bodies for much longer than initially thought. Science from industry, the FDA and independent researchers now links 6:2 FTOH to kidney disease, liver damage, cancer, neurological damage, developmental problems and autoimmune disorders, while researchers also found higher mortality rates among young animals and mothers exposed to the chemicals. Had the FDA seen the data, it is unlikely that it would have approved 6:2 FTOH, said Maricel Maffini, an independent researcher who studies PFAS in food packaging. And though Daikin may have broken the law, it and DuPont, which has previously been caught hiding studies that suggest toxicity in PFAS, are not facing any repercussions. “Those things shouldn’t happen, and if they do then there should be consequences, but oversight is lax,” Maffini said. In 2020, the FDA reached agreements with some major PFAS manufacturers to voluntarily stop using 6:2 FTOH compounds in food packaging within five years. But documents show that the FDA first became aware of DuPont’s hidden study in 2015, and public health advocates say a 10-year timeline to reassess and remove the chemical is unacceptable. Moreover, the FDA phase-out only applies to 6:2 FTOH compounds, and does not include other similar “short chain” PFAS, raising questions about whether the agency is fully protecting the public from the class of potentially toxic chemicals. “I think people need to be able to rely on the FDA to turn science at the agency into real action, and right now that doesn’t seem to be the case,” said Tom Neltner, chemicals policy director with the Environmental Defense Fund. He and Maffini obtained the companies’ studies and related documents from Daikin’s website and the FDA through Freedom of Information Act requests. The 6:2 FTOH compound is part of a newer generation of “short chain” PFAS that were designed to replace older and supposedly more harmful “long chain” PFAS. The industry claims that short chain compounds are uniformly safe and “practically non-toxic”. However, independent researchers like Erika Schreder, science director for Toxic Free Future, have found that PFAS, regardless of chain length, accumulate in the environment and humans, and are toxic. “The fact that we continue to uncover evidence that the current-use PFAS have similar toxicity to the [long chain] compounds that have been phased out makes a strong argument for regulating harmful chemicals like PFAS as a class,” Schreder said. In a statement to the Guardian, an FDA spokesperson defended the agency’s handling of 6:2 FTOH, noting that the studies “do not demonstrate an imminent health hazard” and more studies were needed to draw concrete conclusions about its safety, and that of other short chain PFAS. Daikin and Chemours, a company that in 2015 was spun off from DuPont’s PFAS division, did not respond to requests for comment. DuPont hides alarming new data Industry reports and communications among the FDA and PFAS producers between 2008 and 2020 show how a sequence of inadequate chemical safety analyses, hidden studies and lax oversight created a scenario in which Americans continue to be exposed to the dangerous compound in food packaging. The 2008 6:2 FTOH studies that DuPont submitted to the FDA monitored the impact of high exposure levels to the chemical on two generations of lab rats. The animals suffered kidney failure, liver damage, mammary gland problems, mottled teeth and other issues. However, DuPont and the FDA felt that humans’ exposure would be much lower and, with little supporting evidence, believed that the short chain PFAS would not accumulate in human bodies, Maffini said. She called such studies on PFAS “inaccurate and inappropriate” because the chemicals are toxic at “extremely low levels” and are known to accumulate in animals’ bodies. Indeed, the longer-term DuPont study completed in 2012 found that 6:2 FTOH stayed in lab animals’ bodies for longer than previously thought. Still, DuPont did not alert the FDA or publish the study. Though the law does not require companies to make such information public, the results strongly suggested a health threat, and DuPont “had an ethical obligation to not just publish it, but flag it for the FDA”, Neltner said. Three years later, DuPont partially summarized its 2012 findings in a peer-reviewed 6:2 FTOH study that Maffini said used “cherry-picked” data to support its claim that the compound was safe. Though it omitted the 2012 study’s details, communications show it caught the attention of the FDA, which wrote that the study alerted the agency “to potential biopersistence of [6:2 FTOH] and raised potential safety concerns”. That triggered a safety review, but the process would drag out for about five years as Americans continued to be exposed. Even when DuPont in its 2008 study reported some health problems in lab animals at high exposure levels, it did so in a way that appears designed to confuse, Maffini noted. One passage that revealed that high doses of the chemical lead to blood in rats’ urine read that the doses “resulted in a significant reduction in the number of female rats with blood absent in the urine”. Daikin omits damning science The FDA in 2009 approved the Daikin-developed 6:2 FTOH compound for use in food packaging, partly basing the decision on the company’s studies that suggested that the chemical was non-toxic. But about 10 years later, Maffini and Neltner discovered that Daikin had withheld two studies from the FDA that suggested toxicity to lab animals’ livers and kidneys at low exposure levels – one completed before the FDA approved the chemical, and one after. They caught the omission by cross-checking studies for the chemical posted to Daikin’s website with those submitted to the FDA, and found the data on health effects was never given to the agency. Neltner noted that the law required the first study to be submitted to the FDA. Maffini said they asked Daikin about the omission and the company responded by removing the report from its website, but it can still be found using the Wayback machine site. As part of its safety review of the chemical, the FDA convened a 2018 meeting with Chemours, Daikin and others in the industry at which the agency requested studies related to 6:2 FTOH. Communications confirm that the FDA did not previously have DuPont’s 2012 study or Daikin’s 2007 study. Between 2018 and 2020, three FDA analyses that included Daikin’s and DuPont’s studies broadly concluded that 6:2 FTOH may stick in the human body for years and could be more toxic than the companies had previously suggested. A 2019 communication between the FDA and the PFAS manufacturer Asahi showed urgency on the part of the agency to get the chemical removed from the market, but in July 2020 it announced that four major producers of the compound had agreed to have all food packaging with 6:2 FTOH off the shelves by 2025. In its announcement, the FDA wrote that the extended timeline “balances uncertainty about the potential for public health risks with minimizing potential market disruptions to food packaging supply chains during the Covid-19 public health emergency”. Maffini questioned whether the public’s health was being put first. “The agency’s own scientists were in a rush to get it out of the marketplace so it’s really hard to understand why the FDA agreed to a five-year phase-out,” she said. Neltner also underscored what he and Maffini view as other deficiencies in the FDA’s chemical approval process that contributed to the 6:2 FTOH problem: the agency does not demand sufficient safety data up front and there is no systematic reassessment to determine whether chemicals are safe after they are sent to the market. The FDA again defended its process, stating that the agency “updates our safety assessments as appropriate” and said industry “must provide sufficient information demonstrating that” chemicals are safe. But Neltner said the problems with 6:2 FTOH suggest otherwise. “They’re making grossly inaccurate assumptions that are not defensible,” Neltner said.