A new study found high levels of toxic “forever chemicals” in freshwater fish nationwide. Compared to store-bought fish, the fish examined in the study had an average of nearly 280 times more of these toxic chemicals called PFAS. Particularly high levels were found in fish caught in urban areas.
This study, published in Environmental Research, is concerning news for recreational fisherman who cook up what they catch and communities that rely on subsistence fishing or have cultural traditions that involve fishing. Previous work by the Food and Drug Administration found commercially available fish in grocery stores and restaurants generally had relatively low PFAS levels; experts say store-bought fish are often from offshore fisheries that seem to be less affected.
“Even infrequent consumption of, for example, four meals per year [of freshwater fish] could potentially double the amount of PFOS in your body,” said Tasha Stoiber, one of the study authors and a scientist at the advocacy organization the Environmental Working Group. PFOS is one of many thousands of types of PFAS chemicals.
Some governmental bodies, including in the state of Massachusetts, have focused on measuring and regulating PFAS in drinking water. This study adds to a growing understanding that food can also be a significant source of PFAS exposure.
“This is a consequence of many decades of an unregulated class of chemicals. That pollution has now accumulated in fish,” said Stoiber.
PFAS are manmade chemicals that are used in a wide range of products, everything from firefighting foams to dental floss to nonstick pots and pans. The chemicals are useful in repelling water, oil and grease. However, the chemicals — which take a very long time to break down — are linked to a long list of health concerns, including suppressing the immune system, disrupting the endocrine system and increasing the risk of certain types of cancer.
The study examined over 500 fish samples and 44 different species gathered by the Environmental Protection Agency between 2013 and 2015 across the U.S. Smallmouth bass, largemouth bass and channel catfish tended to have some of the higher levels of PFAS. Other studies have found that populations that are more likely to consume fish — including licensed anglers and Burmese refugees in Western New York state — have higher levels of PFAS in their blood compared to the general population.
Given the level of PFAS contamination across the country, the findings did not surprise Elsie Sunderland, who is an environmental chemist at Harvard and was not involved in the study.
“But this is the first time it has been shown that for people who have traditional practices that include a lot of local fishing activity or there's a community fishery that they're very highly exposed by consuming relatively small amounts of fish. So just one meal,” she said.
She pointed out that other toxins found in fish, such as mercury or PCBs, often accumulate in older fish that are higher on the food chain. In contrast, “PFAS seem to really reflect site-specific contamination,” said Sunderland.
“The big message from that is we really need consumption advisories across the country,” she said, adding that the chemicals are still being widely produced.
Sunderland would like to see movement on both the state and federal level to provide local fish advisories and information on how much can safely be consumed. She would also like to see PFAS chemicals regulated at the federal level.
FAQs
A new study found high levels of toxic “forever chemicals” in freshwater fish nationwide. Compared to store-bought fish, the fish examined in the study had an average of nearly 280 times more of these toxic chemicals called PFAS. Particularly high levels were found in fish caught in urban areas.
Which fish have forever chemicals? ›
Just like mercury, PFAS bioaccumulate up the food chain, so bigger fish, like largemouth bass, generally contain more chemicals than smaller fish. Mercury is more widespread in Maine, but Kopec said PFAS levels near contamination sources are concerningly high.
What are the harmful chemicals in fish? ›
Fish absorb contaminants such as PCBs, PBDEs, dioxins, and chlorinated pesticides from water, sediments, and the food they eat. In contaminated areas, bottom-dwelling fish are especially likely to have high levels of these chemicals because these substances settle to the bottom where the fish feed.
What is the most prevalent group of Pfass detected in freshwater fish? ›
Though it is no longer made in the U.S., PFOS remains the most commonly found — and tested for — PFAS chemical in fish today. The primary maker of PFOS, 3M, announced it would begin phasing the chemical out in 2000.
What fish has the lowest PFAS? ›
While studies are ongoing to answer this question, a new study suggests that eating commercially caught finfish and seafood, such as cod and tuna, have lower concentrations of PFAS when compared to freshwater fish.
Which fish are high in PFAS? ›
Just like mercury, PFAS bioaccumulate up the food chain, so bigger fish, like largemouth bass, generally contain more chemicals than smaller fish. Mercury is more widespread in Maine, but Kopec said PFAS levels near contamination sources are concerningly high.
Why can't you eat freshwater fish? ›
Making a meal of freshwater fish such as largemouth bass, lake trout, or catfish could come with an unwanted helping of a potentially harmful chemical called perfluorooctane sulfonic acid (PFOS).
Are all freshwater fish contaminated? ›
Testing fish for PFAS
National EPA tests show nearly all fish in U.S. rivers and streams are contaminated with PFAS in the parts-per-billion range – even greater than parts per trillion.
Which fish are most contaminated? ›
The most contaminated fish that you should never eat
- Bluefin/Bigeye/Ahi tuna (worst), slightly better Albacore and Yellowfin tuna however still highly contaminated.
- Swordfish.
- Shark.
- King mackerel and Spanish Mackerel.
- Orange roughly.
- Chilean sea bass.
- Grouper.
- Monkfish.
You can't look at fish and tell if they contain chemical pollutants. The only way to tell if fish contain harmful levels of chemical pollutants is to have them tested in a laboratory.
The testing data, from the US Environmental Protection Agency and Food and Drug Administration, showed that consuming a single meal of freshwater fish could lead to similar PFAS exposure as ingesting store-bought fish every day for a year.
Are freshwater fish healthy to eat? ›
“Wild caught, freshwater fish in the United States are far more contaminated with toxic PFAS “forever chemicals” than those commercially caught in oceans, and the highest levels are found in fish from the Great Lakes, a new analysis of federal data suggests.
Are freshwater fish contaminated with PFAS? ›
“PFAS in freshwater fish is at such a concentration that for anyone consuming, even infrequently, it would likely be their major source of exposure over the course of the year,” said David Andrews, a co-author of the study and researcher at EWG.
What is the safest fish to eat? ›
The top 10 healthy fish to include in your diet:
- Cod. ...
- Trout. ...
- Sardines. ...
- Crab. ...
- Haddock. ...
- Tuna. ...
- Mussels. Mussels are inexpensive, sustainable and rich in omega-3 fatty acid. ...
- Prawns. Prawns are a low-calorie seafood, that are low in fat but high in protein.
7 Healthiest Fish to Eat, According to Experts
- Sardines. “Sardines are one of the healthiest fish to eat because they're very high in omega-3s,” says Gomer. ...
- Mackerel. Mackerel is a good source of omega-3 fatty acids, says Sauceda. ...
- Anchovies. ...
- Salmon. ...
- Herring. ...
- Trout. ...
- Tuna.
An analysis of U.S. government data derived from more than 500 fish samples revealed that the majority of fish living in streams, rivers and lakes across the country are contaminated with per- and poly-fluoroalkyl substances (PFAS) at levels almost 300 times higher than found in fish from other sources, including ocean ...
What is the healthiest fish for longevity? ›
5 of the Healthiest Fish to Eat
- Salmon, Wild-Caught (including canned) ...
- Sardines, Wild-Caught (including canned) ...
- Rainbow Trout (and some types of Lake) ...
- Herring. ...
- Orange Roughy. ...
- Salmon, Farmed in Pens (Atlantic) ...
- Mahi-Mahi (Costa Rica, Guatemala & Peru)
Testing fish for PFAS
National EPA tests show nearly all fish in U.S. rivers and streams are contaminated with PFAS in the parts-per-billion range – even greater than parts per trillion. Although the most recent test results found decreasing PFAS levels, freshwater fish are still contaminated at high levels.
What foods have the most forever chemicals? ›
PFA chemicals, used in some pesticides, were identified in a range of foods in 2022, according to results from the latest Government testing.
- Grapes, Oranges, apples bananas and Kiwifruit in a fruit bowl (PA Archive)
- Strawberries are the worst offender, with 95% of 120 test samples containing PFA pesticides (PA Archive)
