Regulators have only recently begun to address a dangerous class of chemicals contaminating the country's water supply, but an as-of-yet unpublished Food and Drug Administration study confirmed for the first time what scientists have long known: It's not just water that's contaminated. Americans are likely consuming per- and poly-fluoroalkyl substances (PFAS)—man-made contaminants—with every meal, from packaged meats to chocolate cake sold at the grocery store.
PFAS are chemicals once commonly used in water-repellent clothing, firefighting foams, non-stick cookware, and other household products. They're known as "forever chemicals" because they linger in the body for years, accumulating over time, and are associated with a wide variety of adverse health effects from increased risk of testicular and kidney cancer to developmental disorders. According to the non-profit Environmental Working Group, 99 percent of Americans have some level of PFAS in their blood. They reach us through water, dust, air—and, now, the FDA says, through food.
That food was a PFAS source has been common knowledge in the scientific community for some time, according to Natural Resources Defense Council staff scientist Anna Reade. "Scientists and health officials have always felt that a large percentage of our exposure comes from contaminated food," she says.
But it might be news to consumers and even retailers selling food contaminated by PFAS. As advocates have warned for years, there's been little action to ban or even evaluate the safety of PFAS in food at the federal level: Although epidemiology studies have long confirmed PFAS levels in fish and other foods, the FDA only recently confirmed news of its first test.
The FDA researchers sampled items from three, undisclosed cities in the United States in a yet unpublished study obtained this week by the Associated Press. The findings are dramatic—some foods turned up PFAS levels of 865 parts per trillion, and as high as 17,640 ppt in chocolate cake, well above the 70 ppt the Environmental Protection Agency sets as its current health advisory level for drinking water. (Other agencies have criticized the EPA's water limits as too high.)
People, of course, consume more water than cake—but the U.S. has no existing standard for PFAS in food. That doesn't mean it's not a health risk.
"If you're thinking about toxic impacts, you need to know about total exposure," says Carla Ng, assistant professor of civil and environmental engineering at the University of Pittsburgh. "Having only the drinking water picture is only a small side of that. We need to know where the biggest source of exposures in humans to different PFAS are."
The contamination in foods is likely even more widespread than the FDA results suggest, Ng warns. PFAS have been found in commercial baby food and breast milk; other studies have found eating contaminated seafood increased PFAS concentration in humans.
FDA spokeswoman Tara Rabin told the Associated Press that the agency thought the contamination it found was "not likely to be a human health concern." Experts who study PFAS say it will take more research to understand the risks.
"Although levels in some of the individual foods appear to be pretty high, relative to 70 parts per trillion health advisory ... they're unlikely to be consumed on a chronic basis in the same way water is consumed," says Jamie DeWitt, a toxicology professor at East Carolina State University. "The data leads to the question: Is it time for a comprehensive risk assessment that includes more than just drinking water?"
The FDA only tested for 16 PFAS, according to several experts, and there are thousands of these chemicals in use worldwide. On top of that, Reade notes that many communities affected by PFAS are small, rural communities. "None of them are picked up in the national testing," she says.
The chemicals can enter the food supply in many ways: A farmer irrigates with PFAS-contaminated water or applies sewage sludge to a field, which then contaminates the soil. Those chemicals get taken up by crops, and those crops are fed to animals—and so PFAS move their way up the food chain. The FDA's results confirmed this, showing contamination was higher in milk and vegetables produced near an industrial PFAS plant and an Air Force base, a common source of PFAS contamination.
Some of the compounds also reach consumers at the grocery store. The FDA has approved certain PFAS for use in food packaging, including items like grease-resistant paper plates, cardboard take-out containers, and popcorn bags. And while the industry has phased out PFAS regulated by the EPA over the years, the FDA's test results suggest companies are replacing the old PFAS compounds with others, including that found in the chocolate cake, according to University of Michigan epidemiologist Sung Kyun Park. "We need to monitor this other replacement," he says. "The bottom line is that contamination is everywhere."
Washington State banned PFAS in food packaging this year, and other states are following suit. But advocates say the federal government needs to take action. "[The FDA needs] to consider those uses they approved may yield the next round of environmental contamination," Tom Neltner, chemicals policy director for Environmental Defense Fund, said in a conference call on Thursday.
Scientists and environmental advocates would like to see federal agencies enforce stricter standards for exposure, regulate biosolids application, and ban PFAS in food packaging. "The picture that comes across to me is that ... these substances are everywhere, and until we stop using them, we're not going to be able to get away from them," Ng says.
Stopping contamination at the source is one way to start—which brings Reade back to the chocolate cake. Did PFAS come from contamination in the baking process? From the grease-proof paper used to serve the cake? "There's no way for us to know, which is very frustrating," she says. "It just points to a general problem with this process in our country. We should have more transparency in what we buy."