Per- and polyfluoroalkyl substances (PFAS), commonly known as 'persistent chemicals,' have become contaminants of global concern because of their difficulty in breaking down in the environment. These chemicals are widely used in cleaning products, paints, carpets, non-stick cookware, and some personal care products (e.g., sunscreens and shampoos). However, PFAS spreads through air, water and soil and eventually enters the food chain, including crops and animals, and even aquatic products. Recently, the U.S. Food and Drug Administration's (FDA's) latest research and actions to address PFAS contamination in aquatic products have garnered a great deal of attention both inside and outside the industry.

The FDA tested 81 retail aquatic product samples for PFAS between 2021 and 2022, covering a wide range of categories such as canned tuna, Atlantic salmon, tilapia fillets, wild blue crab meat and claws, farmed shrimp, Alaska pollock rods and canned clams. The results of these samples, which came from a variety of countries and regions, showed that some of the canned clams imported from China contained detectable levels of perfluorooctanoic acid (PFOA, a type of PFAS) at a 'possible health risk' level, and the FDA assessed that the average consumer would consume more than about 10 ounces (about 283 pounds) per month of the canned clam products with the highest levels of PFOA. 10 ounces (about 283 grams) per month for the average consumer, while children should be limited to no more than 2 ounces (about 57 grams) per month. This finding led to the recall of some brands of smoked clam products in 2022, including Bumble Bee Foods and Crown Prince brands.

Studies have shown that PFAS contamination can bring about a range of health problems, including developmental issues, changes in liver function, reduced immune response, and an increased risk of certain cancers. While the FDA noted that the levels of other types of PFAS in most aquatic product samples 'probably do not pose a health risk,' further investigation is needed into the issue of PFOA in imported canned clams, as well as PFAS contamination in clams as a whole.

In order to more fully assess U.S. consumers' intake of PFAS through food, the FDA plans to further expand the scope of testing. The focus will include filter-feeding shellfish such as clams, oysters, mussels and scallops. In addition, FDA will conduct a survey of 600 samples of the top 10 most popular fish species for U.S. consumers. The ranking was released by the National Fisheries Institute based on statistics from the National Oceanic and Atmospheric Administration (NOAA).2022 data shows that shrimp reigns at the top of the list with 5.5 pounds of consumption per capita, followed by salmon (3.22 pounds), canned tuna (2.2 pounds), tilapia (1.01 pounds), and balsa (0.86 pounds).