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Persistent Pollutants

PFAS undetectable in most processed foods, US FDA says

Environmentalists dispute findings, raise questions about detection limits

by Britt E. Erickson
August 27, 2021

Tuna sandwich on a piece of lettuce on a wooden board next to an opened can of tuna and sliced onions and tomato.
Credit: Shutterstock
The US Food and Drug Administration is investigating PFAS in seafood after finding the chemicals in canned tuna and frozen fish sticks.

The US Food and Drug Administration did not detect per- and polyfluoroalkyl substances (PFAS) in most processed foods, including baby foods, in an analysis of 167 items commonly consumed in the US. But the agency did find perfluorooctane sulfonic acid (PFOS) in three products—frozen fish sticks, canned tuna, and protein powder.

The levels of PFOS in canned tuna (76 parts per trillion) and protein powder (140 ppt) were above the Environmental Protection Agency’s drinking water health advisory level of 70 ppt. PFOS is linked to cancer and other adverse health effects, and, like other PFAS, persists in the environment.

Despite the findings, the FDA is not warning consumers to avoid the three products. The agency claims that the sample sizes were limited and cannot be used to infer levels of PFAS in the US food supply.

The FDA has analyzed 440 foods for PFAS since 2019. The latest results represent foods distributed nationally. Previous samples were collected from areas with known PFAS contamination.

In both the recent analysis and previous ones, the FDA detected PFAS in seafood products. The agency is now analyzing commonly consumed seafood in the US to determine whether additional sampling of fish and shellfish is needed.

“As we continue to collect and analyze the data being generated, we are in a better position to determine how to strategically and effectively work with our state and federal partners to reduce dietary exposure to PFAS,” Susan Mayne, director of the FDA’s Center for Food Safety and Applied Nutrition, says in a statement.

The Environmental Working Group (EWG), an advocacy organization, points out that many of the foods the FDA listed as having PFAS below the detection limit likely contain quantifiable levels of these chemicals. The FDA changed the criteria it uses for establishing such detection limits in November 2019. This prompted the agency to replace more than 100 PFAS concentration numbers for foods reported in June 2019 with a finding that simply states the level was less than the analytical method’s limit of detection.

“Food is suspected of being a major source of exposure to PFAS,” EWG senior scientist David Andrews says in a statement. “We urgently need more comprehensive testing of our food supply with lower detection limits and the ability to identify all PFAS,” he says.

EWG and other environmental groups are also urging the FDA to consider all exposures to PFAS, including in drinking water, when evaluating the health risks of PFAS in food. Individual foods may be below a certain threshold, but consumers can be exposed to harmful amounts of PFAS when all sources are considered together, they say.



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