Sun, December 12, 2021
The American food supply is likely riddled with far more dangerous toxins than the average consumer would anticipate, and scientists say they lack sufficient, streamlined data about the "forever chemicals" lurking in food packaging and farmlands.
While state and federal agencies have improved data collection for PFAS - perfluoroalkyl and polyfluoroalkyl substances - in drinking water, only "anecdotal evidence" exists for other exposure sources, such as ingestion of food, inhalation of dust and dermal uptake, Elsie Sunderland, an environmental chemistry professor at Harvard University, told the Subcommittees on Environment and Research and Technology earlier this week.
"While we've made progress in understanding the contribution of drinking water as an exposure source, the relative importance of these other sources is basically not understood," Sunderland said in a Friday interview with The Hill.
PFAS include thousands of toxic compounds linked to kidney, liver, immunological, developmental and reproductive issues. While these substances are most known for contaminating groundwater via firefighting foam, they are also key ingredients in food packaging and household products like nonstick pans, toys, makeup and waterproof apparel.
Sunderland recalled how she and a student were running samples from a contaminated groundwater site, when they decided to test PFAS levels in the compostable food packaging they had with them. They found that the levels were "higher than all the contaminated groundwater."
Scientists say that PFAS-coated packaging is not just problematic for the consumer of that particular meal.
"When you go to throw your compostable food packaging in the compost pile, you're contaminating your compost, which you then send to these big places to be composted," Abigail Hendershott, executive director of the Michigan PFAS Action Response Team (MPART), told The Hill.
The E.U. has deemed the dietary intake of PFAS so problematic that several countries have banned it in food packaging, Sunderland said in her testimony. By contrast, data on PFAS exposures in the U.S. food supply are minimal and analytical methods in research are limited - likely leading to an underestimation of exposures.
"Europe is just a little bit ahead and they have more of a precautionary approach," Sunderland told The Hill. "Here we're really into quantitative risk assessment and demonstrating that something causes an appreciable harm before we regulate."
But that type of "reactive management strategy" doesn't work well when targeting chemicals like PFAS, since scientists cannot "catch up" with the thousands of chemicals in the class, according to Sunderland.
The Food and Drug Administration recently undertook a "Total Diet Study" that looked at PFAS content in nationally distributed processed foods, finding that 164 of the 167 foods tested had no detectable levels of PFAS. The FDA's acting commissioner, Janet Woodcock, said in a statement that the administration would work to understand PFAS concentrations in foods, aiming "to ensure the U.S. food supply continues to be among the safest in the world."
Sunderland said she found this study problematic due to its small size and lack of specific information about the samples. The sample size was not representative of the U.S. population, she continued, noting that if the findings were multiplied by the amount of food that people eat, the results not meet the safety levels established by the European Food Safety Authority.
"I also think there's a bit of a mixed mandate that FDA has because they sell food, but they also are charged with food safety," Sunderland said.
The murkiness regarding levels of PFAS in the nation's food supply is not limited to packaging. In many states, like Maine and Michigan, high levels of PFAS have also been found on farmlands, where mixtures of biosolids and industrial sludge have been used as fertilizer, according to Sunderland's testimony.
"Michigan has a rich history of manufacturing and farming, and when those two exist together, there's a concern about the potential for PFAS to enter the food supply," added Hendershott, from Michigan's MPART initiative, in her subcommittee testimony.
MPART was established in 2017 as a body to protect drinking water standards and investigate sources of PFAS in Michigan, including in food chain staples like fish.
"What Michigan's really been doing is a multifaceted approach to evaluating PFAS occurrence in our state," Hendershott told The Hill. "And it all ties into food safety."
Hendershott said that greater federal support is necessary to understand how PFAS enters the food cycle, like when cattle encounter PFAS by grazing on PFAS-contaminated fields, according to her testimony.
"This is the foundation of food supply, going straight to our farmers and ensuring our farmers have good, safe drinking water, they have fields and crops that are not contaminated with PFAS," Hendershott told The Hill.
In addition to a lack of data on PFAS in U.S. food supplies, there are limitations to current analytical methods. Sunderland said that officials, therefore, "are systematically underestimating exposures to these compounds," according to her testimony.
Sunderland stressed the need for new analytical tools to detect PFAS precursors - compounds that break down into PFAS but are difficult to detect - as well as simpler measurement techniques for routine monitoring across communities.
She also called for the Environmental Protection Agency and the National Institute of Standards and Technology to standardize methods and laboratory intercomparisons, to ensure that data generated across multiple labs is comparable. Doing so, her testimony explained, could help "address the chemical whack-a-mole situation we are now experiencing."
"The 'whack-a-mole' situation is basically - we phase out one PFAS, and then industry introduces a new one that's chemically slightly different and tells everybody it's safe," Sunderland said. "It takes 20-30 years before we really understand, using human cohort data, that this is the problem. And by that time, there's already a new compound."
In his opening statement, however, Rep. Michael Waltz (R-Fla.) maintained that "scientific research is determining not all PFAS chemicals entail the same risks."
Waltz added that "more research is needed to better understand the individual properties and characteristics of PFAS."
"We don't need these chemicals in most of the consumer products, in my opinion and the opinion of most of my colleagues," Sunderland countered, in her conversation with The Hill.
At a congressional level, Sunderland said she would like to see more support for ongoing research at the National Institutes of Health, the Centers for Disease Control, the EPA and the U.S. Geological Survey - looking at exposure pathways for diverse demographic groups in a statistically representative manner.
Hendershott, meanwhile, called for "better predictive models for PFAS behavior," stressing in her testimony that measurement techniques have outpaced risk assessment abilities.
Hendershott added she would like to see more studies on which crops have the least PFAS uptake and whether there are any types of PFAS-resistant crops that could be grown. But such research, she agreed, requires standardization so that methodologies and results are comparable among laboratories.
"There needs to be a lot more study and research on dietary exposure - how that happens," Hendershott said. "Food packaging obviously could be a source. But there are a lot of other potential sources that need to be researched. So it is kind of a black box at this point that needs a lot more study."
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