FDA recently released the results of its seafood survey it conducted to measure the amount of per- and polyfluoroalkyl substances (PFAS) in 81 seafood samples of clams, cod, crab, pollock, salmon, shrimp, tuna, and tilapia collected at retail. FDA determined that the estimated exposure to perfluorooctanoic acid (PFOA) from certain samples of imported canned clams is likely a health concern. Two companies have initiated voluntary recalls as a result of the FDA sampling and health hazard analysis of the levels of PFOA found in the products. FDA plans to conduct broader testing of canned and fresh clams for PFAS in the future.


Per- and polyfluoroalkyl substances (PFAS) are a group of chemicals that have been used in a range of consumer products for decades. Research shows that some PFAS (e.g., PFOA and PFOS) may be linked to certain health effects. To understand the potential dietary exposure to PFAS from food, FDA first conducted a survey of PFAS in the general food supply. Of the 532 Total Diet Study (TDS) samples FDA tested for PFAS, only ten samples contained detectable levels of certain PFAS, eight of which were seafood.1

FDA PFAS Seafood Survey & Findings

To better understand the sources and levels of PFAS chemicals in seafood, FDA conducted a targeted survey for PFAS in the most commonly consumed seafood. On July 6, 2022, FDA released the testing results from the survey based on 81 retail seafood samples of clams, cod, crab, pollock, salmon, shrimp, tuna, and tilapia, most of which were imported to the United States.2 60 of the 81 samples contained detectable levels of PFAS, with most samples containing more than one type of PFAS detected.

When FDA identified detectable levels of PFAS, it evaluated individually the PFAS detected that have toxicological reference values. FDA developed toxicological reference values for six different PFAS: PFOA, PFOS, PFNA, PFHxS, HFPO-DA [GenX], and PFBS.3

In focusing on the samples showing detectable levels of these 6 types of PFAS molecules for which the agency has toxicological reference values, FDA determined that the estimated exposure to PFOA, from certain samples of canned clams, likely presented a health concern.4 The agency found detectable levels of PFOA in canned clams, with the two highest levels of PFOA reported as 19,822 parts per trillion (ppt) and 20,133 ppt. The samples with the highest levels both were from China. FDA concluded the PFOA levels could present a potential health concern to consumers who eat more than approximately 10 ounces of the clams per month. The agency also stated the clams pose a possible health concern for young children who consume 2 ounces of the clams per month. Notably, FDA found the levels of the other types of PFAS evaluated in the clams, as well as the PFAS evaluated for all other seafood samples, are not likely to be a health concern.

Voluntary Recalls and Next Steps

After learning the findings of the FDA seafood survey, the two canned clam companies with the samples containing the highest levels of PFOA recalled the canned clam products from the market.

FDA also stated that they are working with the canned clam distributors involved in the survey to understand the possible sources of PFAS so that the distributors can work to reduce the levels of PFAS in their products. Further, the agency plans to conduct further testing on canned and fresh clams, both domestic and imported.

We will continue to monitor the legal and regulatory developments related to PFAS chemicals in food.