WASHINGTON – A new study warns that eating just one serving of freshwater fish, such as catfish, trout or salmon, could expose people to a large amount of harmful chemical compounds.
Environmental Working Group researchers have discovered elevated levels of so-called “forever chemicals” in fish caught in U.S. lakes and rivers. Their study found that eating just a single serving of freshwater fish could equal a month’s worth of drinking water with PFAS at a level high enough to be harmful to consumers.
PFAS, or perfluoroalkyl substances, are a group of more than 9,000 different chemicals, some of which are already banned or highly restricted. Manufacturers commonly use them in nonstick cookware, food packaging, stain repellants, coatings, and firefighting foams.
PFAS chemicals are nearly impossible to destroy. They can accumulate in animals along the food chain and also contaminate everything from drinking water to food and personal care products. PFAS can build up in our bodies and never break down. Studies have found them in the blood of virtually everyone, including babies.
Studies have also linked very low doses of PFAS in drinking water to suppressing the immune system, weakening the effectiveness of vaccines and increasing the risk of certain cancers. Researchers believe that PFAS can also increase cholesterol, reproductive and developmental problems, and other health problems.
Environmental Working Group (EWG) scientists found that the average amounts of PFAS in freshwater fish in the US were 280 times greater than the chemicals ever detected in some commercially caught fish. The results estimate that eating a single freshwater fish caught in a lake or river could result in PFAS exposure equal to consuming store-bought fish daily for an entire year.
“People who consume freshwater fish, especially those who catch and eat fish regularly, are at risk of having alarming levels of PFAS in their bodies,” says lead study author David Andrews, Ph.D. ., EWG senior scientist, in a press release. . “Growing up, I went fishing every week and ate those fish. But now, when I see fish, all I think about is PFAS contamination.”
What chemicals are hidden in fresh water?
The study’s authors say the most common chemical found by far was PFOS, or sulfonic acid, accounting for about three out of four total PFAS detections on average.
“These test results are impressive,” adds Scott Faber, EWG’s senior vice president of government affairs. “Eating one bass is equivalent to drinking PFOS-contaminated water for a month.”
Researchers say consuming freshwater fish contaminated with PFOS can lead to “significant” increases in blood serum levels of the chemical forever. Even occasional consumption of freshwater fish could increase PFOS levels in the body.
“The degree to which PFAS has contaminated fish is surprising,” says Nadia Barbo, a graduate student at Duke University and principal investigator of this project. “There should be a single health protection fish consumption advisory for freshwater fish across the country.”
The researchers analyzed data from more than 500 samples of fish fillets collected between 2013 and 2015. The average level of total PFAS in fillets was 9,500 nanograms per kilogram, with an average of 11,800 nanograms per kilogram in fish of the Great Lakes.
“PFASs contaminate fish in the United States, with the highest levels in the Great Lakes and fish caught in urban areas,” says study co-author Tasha Stoiber, Ph.D., senior scientist at EWG. “PFASs don’t go away when products are discarded or thrown away. Our research shows that more common disposal methods can end up leading to more environmental contamination.”
Who is polluting America’s waterways?
Freshwater fish are an important source of protein for many Americans, but PFAS contamination threatens those who can’t afford seafood at the grocery store.
“Identifying sources of PFAS exposure is an urgent public health priority,” says Stoiber.
Researchers estimate there may be more than 40,000 industrial PFAS contaminants in the United States. These include manufacturing facilities, municipal landfills, wastewater treatment plants and airports. Contaminated water has spread PFAS to soil, crops and wildlife, including fish.
“For decades, polluters have dumped as much PFAS as they wanted with impunity into our rivers, streams, lakes and bays. We must turn off the tap on PFAS contamination from industrial discharges, which affects more Americans every day.” notes EWG’s Faber.
Tests have revealed that almost all fish in American rivers and streams are contaminated with PFAS in the parts per million range, even higher than parts per trillion. Although more recent tests have found decreased levels of PFAS, freshwater fish still show high levels of the chemicals.
“EPA must move quickly to establish regulations for industries most likely to release PFAS into the environment. Downstream communities, in particular, have suffered the consequences of unregulated PFAS discharges for too long,” concludes Faber.
The results are published in the journal Environmental Research.
South West News Service writer Stephen Beech contributed to this report.