The containers that hold your takeout dinner may harbor an invisible threat: fluorinated compounds that persist in our bodies long after we ingest them. They are among almost 5,000 perfluoroalkyl and polyfluoroalkyl substances, or PFAS, a class of chemicals that have been associated with health hazards that include liver damage, birth defects, cancer, and impaired immunity.
PFAS repel grease, oil, and water—properties that have come in handy for a wide range of uses since the chemicals were first created in the 1940s. For decades, they have kept food from sticking on pans, hot oil from burning a hole in the microwave popcorn bag, and grease from leaking out of pizza boxes and burger wrappings. The bond between chains of carbon and fluorine atoms is extraordinarily sturdy, which means the compounds persist in the environment and can accumulate in humans and animals. PFAS have been found in the blood of nearly every American tested, according to the Centers for Disease Control and Prevention.
Last week, the US Food and Drug Administration announced a voluntary agreement with three manufacturers of chemical products used in food packaging to phase out a PFAS called 6:2 fluorotelomer alcohol, or 6:2 FTOH. (A fourth manufacturer joined the agreement but had already stopped selling the products.) The move comes as food retailers face growing pressure to switch to PFAS-free packaging. Companies as varied as Taco Bell and Whole Foods have vowed to be proactive in seeking wrappings and containers without the chemicals.
“This action follows new analyses of data that raised questions about potential human health risks from chronic dietary exposure—findings that warrant further study,” FDA commissioner Stephen Hahn and Susan Mayne, director of the FDA’s Center for Food Safety and Applied Nutrition, wrote in a statement. “This phase-out 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.”
Earlier this year, FDA scientists published rodent studies showing that 6:2 FTOH breaks down into a metabolite that persists in blood plasma and body tissues. FDA scientists also analyzed toxicity data and found evidence of liver, kidney, immune, and reproductive effects related to the compound in rodents. The new findings contradict some previous assumptions about how 6:2 FTOH acts in the body, the scientists wrote, and previous assessments “may significantly underestimate the risk to human health.”
The FDA doesn’t consider all PFAS to be hazardous, and there’s no immediate health risk from the existing products, agency spokesperson Peter Cassell told WIRED. The phase-out will take up to five years. Beginning in January 2021, manufacturers have three years to wind down production, and then existing products can still be used for another 18 months. The FDA will monitor the progress in reducing the use of 6:2 FTOH and will continue to study PFAS.
The FDA action received muted praise from environmental health advocates and scientists. “I’d say it’s better than nothing. It’s a step in the right direction,” says Linda Birnbaum, a toxicologist and former director of the National Institute of Environmental Health Sciences.
Removing these “forever chemicals” from the food supply has long been a goal of consumer and environmental health advocates. Their pervasiveness became clear through a 2017 study led by environmental chemist Laurel Schaider at Silent Spring Institute in Newton, Massachusetts, a research group that focuses on environmental health risks. Her study involved tests of about 400 fast-food containers from around the US. The scientists detected fluorine, an indicator of the presence of PFAS, in 38 percent of sandwich and burger wrappers and 56 percent of bread and dessert wrappers.
But it isn’t just the likelihood that people could be exposed to these chemicals through eating fast food that concerns Schaider. “Those chemicals live on. They go into a landfill. They have the potential to end up in the environment,” she says.
The FDA has previously rolled back the use of PFAS. The agency took a similarly negotiated approach in 2011 when it worked with manufacturers of food packaging substances to voluntarily stop using a kind of PFAS with chains of eight carbon atoms or more—a version thought to be more hazardous to health. At the time, agency officials noted in a statement that “studies indicate that these C8 compounds persist in the environment and can have toxic effects on humans and animals.”
Schaider and colleagues found evidence of that persistence last year when they analyzed data on blood levels of certain long-chain forms of PFAS and linked them to dietary information. The data came from the US National Health and Nutrition Examination Survey, which conducts lab tests and surveys of 5,000 people each year. People who reported eating microwave popcorn every day had 39 percent to 63 percent higher blood levels of the five types of PFAS studied, and PFAS levels dropped progressively as people reported eating more home-cooked meals.
PFAS are widespread in part because they’ve had so many uses, including in stain-resistant carpeting, upholstery, and table cloths. In an emailed statement to WIRED, the Alliance for Telomer Chemistry Stewardship, a global organization that represents manufacturers of products that contain certain types of PFAS such as those in food packaging, notes that C6 fluorotelomer-based products—a type of short-chain PFAS—are used in first-responder gear and medical garments, among other critical products. The “fluorotelomer products … have undergone rigorous testing and analysis for potential effects on both human health and the environment,” read a statement from the alliance emailed to WIRED.
“The specific products being phased out of food packaging have been reviewed by FDA prior to authorizing their use in the US, and are supported by an extensive body of health, safety, and exposure data,” the statement continued. Recently, after reviewing data from rodent studies, the FDA requested further study, which the alliance, in its statement, said underscores the rigor of the regulation of food packaging products. “As a result of FDA’s continuous oversight of these products, the Agency concluded that newly available data raised questions regarding an already evaluated potential trace-level impurity that may be found in these products—6:2 fluorotelomer alcohol (6:2 FTOH),” the statement continues. “Specifically, FDA questioned whether the existing body of scientific studies regarding certain health effects is complete with respect to this 6:2 alcohol. In response to these questions, the member companies worked proactively with FDA. It is important to emphasize that FDA did not conclude that the products at issue are unsafe. The agency only raised questions about whether additional studies are warranted.”
Some consumer advocates and toxicology and environmental health researchers have called the FDA’s approach a “whack-a-mole” process of studying and addressing health concerns of just certain types of PFAS—only to find new problems with another group of PFAS. “ Are the substitutes just going to be unfortunate substitutes?” asks Birnbaum, who also headed the National Toxicology Program. “Are we going to move from one short chain [PFAS] to another short chain until we find out that one has a problem?”
Covid-19 adds a new dimension to those concerns. Most of the immune studies on PFAS have involved long-chain forms known as PFOA and PFOS. In an extensive 2016 review of more than 150 studies, the National Toxicology Program concluded that these two forms are “presumed to be an immune hazard to humans” and cited “a high level of evidence” of suppression of the antibody response from animal studies and “a moderate level of evidence from studies in humans.”
While other PFAS haven’t been as well-studied, that isn’t the same as giving them a green light. FDA scientists who analyzed industry data on 6:2 FTOH and its metabolites reported signs of immune effects in rodents. This summer, the Agency for Toxic Substances and Disease Registry, a part of the CDC, issued a “statement on potential intersection between PFAS and Covid-19.” The agency noted that “little is known” about how PFAS exposure could affect the risk of infection with Covid-19 and that research is needed. “CDC/ATSDR recognizes that exposure to high levels of PFAS may impact the immune system. There is evidence from human and animal studies that PFAS exposure may reduce antibody responses to vaccines and may reduce infectious disease resistance,” the statement read.
It’s an important research question, says Birnbaum, who notes that scientists who have measured PFAS in groups of people as part of environmental health studies could track them during the pandemic and compare them to a less-exposed cohort. “We know some of the PFAS do suppress the immune system in humans,” she says.
Meanwhile, some political pressure is building to speed up the removal of PFAS from food wrappers. Last month, the New York state legislature voted to ban PFAS in food packaging, joining Washington state, Maine, and the cities of San Francisco and Berkeley, which impose similar restrictions. Whole Foods, Trader Joes, and Taco Bell are among other companies that have already pledged to avoid buying food packaging that contains PFAS.
And on Thursday, those efforts got a boost from the advocacy campaign Mind the Store and environmental health nonprofit Toxic-Free Future, which seek to influence retailers, policymakers, and public opinion on matters of chemical safety. The groups released an online report showing that PFAS turn up in some food wrappers provided by well-known chains. The study, which has not been peer reviewed or published in a journal, is part of a broader campaign by advocates to push for a ban on these chemicals in food packaging.
Inspired in part by the Silent Spring Institute study of fast-food containers, staff members from the advocacy groups requested unused wrappers from the three leading fast-food burger chains and three healthy food chains, at a total of 16 locations in New York City, Maryland, Seattle, and Washington, DC. They collected 38 samples, including some duplicates so they could compare the same wrappers from different geographic regions and make sure the results from wrappers from the same locations were consistent.
They placed the wrappers in sealed plastic bags, then turned them over to Galbraith Laboratories in Knoxville, Tennessee, an independent lab that performed tests on them to determine fluorine content. (Because PFAS are fluorinated compounds, detecting fluorine is an indicator of their presence.) The lab used a testing threshold of 100 parts per million of fluorine, a cutoff similar to the one used by compost certifiers who want to exclude items with PFAS. These levels don’t indicate a risk of incurring any particular health problem; they’re simply considered a reliable indicator of the chemicals’ presence.
Overall, the lab found levels above the 100 ppm threshold in two of nine sandwich wrappers (from five different restaurant chains), in all the small paper bags they tested from the three fast-food chains, and in all molded fiber bowls they tested from the healthy food chains CAVA, Sweetgreen, and Freshii.
In particular, they found that a Big Mac clamshell box and McDonald’s fry and cookie bags exceeded the 100 ppm threshold of fluorine, although other wrappers for burgers, Egg McMuffin, and McChicken sandwiches did not. Cardboard boxes for McNuggets or fries also had low or undetectable fluorine levels. At Burger King, one Whopper wrapping out of three tested above that threshold for fluorine; bags for chicken nuggets and cookies also tested positive, although paperboard boxes did not. Only a cookie bag exceeded the screening level at Wendy’s. Ironically, the healthier outlets fared worse, as all the molded fiber bowls for grains or salad showed levels of fluorine that were higher than any levels detected in the fast-food wrappers.
The report drew immediate results—of just the type desired by the advocates. On the eve of its release, officials from the Mediterranean fast-casual restaurant chain CAVA announced that they would eliminate PFAS in their food packaging within a year. “At CAVA, we care about our impact on our communities and on the world at large,” a CAVA spokesperson wrote in an email to WIRED. “As part of our ongoing environmental and social responsibility efforts we are actively working to ensure our sustainable packaging continues to be responsibly sourced, compostable, functional, and now PFAS free. We are pledging to eliminate PFAS from our food packaging by mid-2021, and will publicly share progress on this commitment in the year ahead.”
Freshii, a healthy fast-casual chain, also says they will move toward alternatives. Veronica Castillo, Freshii’s vice president for marketing, told WIRED in an email: “Freshii is in the final stages of transitioning its 16- and 32-ounce pulp bowls to a version that is fully PFAS-free. Freshii intends to roll out these PFAS-free bowls in the early part of 2021, if not before.”
Even before it was included in the Mind the Store and Toxic-Free Future analysis, officials from the salad restaurant Sweetgreen had announced that they would eliminate PFAS from bowls by the end of this year. “We originally introduced compostable containers to make a positive impact on the food ecosystem, however, given recent concerns around PFAS, we started working with new and existing suppliers as well as an independent safety expert to find a more sustainable and compostable solution,” read a Sweetgreen statement emailed to WIRED. “This past January, we partnered with Footprint to pilot compostable, PFAS-free bowls in our San Francisco stores with a goal of rolling out this new packaging nationwide by the end of 2020 at which time they'll also be made domestically and out of post-industrial recycled paperboard." (Footprint is a technology firm focused on creating sustainable packaging and alternatives to single-use plastic.)
Burger King officials also responded to the report and the FDA’s announced phase-out by promising to seek alternatives. “We are looking forward to extending our safe ingredients policy to include the removal of the short-term PFAS recently identified by the FDA,” a spokesperson for Restaurant Brands International, Burger King’s parent company, wrote in an email. “We will work with our suppliers to remove them from all packaging by or, where feasible, earlier than the three years recommended by the FDA.”
A spokesperson for McDonald’s, the world’s largest burger chain, responded to a query from WIRED by touting the company’s commitment to eliminating PFAS but didn’t offer specifics: “The safety and well-being of our communities is our top priority. We’ve eliminated significant subset classes of PFASs from McDonald’s food packaging across the world. We know there is more progress to be made across the industry, and we are exploring opportunities with our supplier partners to go further.”
Representatives from Wendy’s did not respond to a request for comment from WIRED.
While lauding the commitments announced by the healthy fast-casual chains, Mike Schade, director of the Mind the Store campaign, still criticized other fast-food leaders. “We’re extremely disappointed by the lack of action by the burger chains,” he says. “These are three of the largest fast-food chains in the US. With the pandemic, more and more people have been getting takeout, and these companies could play a big role in reducing our exposure to these hazardous chemicals.”
As more states ban the chemicals and some chain restaurants avoid them, manufacturers of food packaging may feel compelled to find other ways to keep the juice and grease from leaking out, says Laurel Schaider of Silent Spring. “There’s going to be more momentum,” she predicts.
For people who need a break from the kitchen or want to support their local restaurants, Schaider says to pay attention to the takeout containers. In her research, she found that thicker paperboard boxes were less likely to contain PFAS; likewise, none of the paperboard cartons used for fries or desserts that were tested by Mind the Store and Toxic-Free Future met the threshold indicating they contained PFAS.
But if concerned consumers want to do more to avoid the “forever chemicals,” her advice is simple: Skip the takeout altogether. “We all know eating more fresh foods is better for our health,” Schaider says. “It’s yet another reason to eat more fresh foods when we can.”