A single serving of freshwater fish can deliver as much PFAS “forever chemicals” as drinking a month’s worth of water tainted with the toxins, a new study says, echoing a Colorado study last year that found the dangerous compounds in every fish sample from popular state waters.
An analysis of EPA samples by the nonprofit Environmental Working Group, published Tuesday in the journal “Environmental Research,” compared the PFAS ingestion from eating one fish portion to drinking water tainted at 48 parts per trillion for a whole month. In June, the EPA lowered its recommended guidelines for two of the thousands of PFAS variations, PFOA and PFOS, from a maximum of 70 parts per trillion in drinking water down to 0.004 and 0.02 parts per trillion, respectively.
There is no EPA or Colorado standard for the amount of PFAS chemicals allowed in fish caught by anglers or sold to consumers. Grocery store seafood tested by the U.S. Food and Drug Administration did not test nearly as high for PFOS, one of the most potentially dangerous of the thousands of varieties of PFAS compounds, the EWG study said.
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Lower income anglers who rely on fresh caught fish for sustenance, and cultures that consume their own catch more regularly, are more vulnerable to the contamination, the study said. That makes fresh caught fish yet another environmental justice issue, with disproportionate impacts from historic pollution, as scientists find PFAS toxins collecting in more and more places.
Past random sampling of human blood has shown PFAS in the bloodstream of nearly everyone on Earth. The water- and fire-repellent chemicals have been used for decades in plastics and coatings ranging from carpet to fast food wrappers to firefighting foam to cosmetics. PFAS sheds from the consumer and industrial products into sewage, stormwater drainage, and freshwater streams and lakes.
The EPA and state officials across the country must research and establish safe fish consumption levels given the extent of PFAS contamination, said co-author and chemist David Andrews, of Environmental Working Group.
“Across the country, levels are staggeringly high in freshwater fish,” Andrews said. “Even very infrequent consumption” would lead to elevated blood levels of potentially dangerous chemicals, he said.
There may be a small amount of hope for the future of battling PFAS contamination from study results showing a decrease in the most recent fish samples from earlier tests taken in the same area, Andrews said. Still, even those diminished results are far too high, as the EPA steadily lowers the amount of PFAS exposure it considers safe in drinking water.
Long-term reduction of PFAS in the food chain is only possible through eliminating the sources of manufacturing and leaching of the chemicals into waterways, Andrews and other researchers say. It takes decades for PFAS levels in humans to begin clearing out of the bloodstream.
“There’s no easy solution,” Andrews said. “It ultimately comes back to regulation of entry of PFAS” into the environment, and “it’s a slow process,” he added.
To test for PFAS almost anywhere in the United States is to find PFAS. Local and state regulators in Colorado have found drinking water sources contaminated by PFAS in runoff from Air Force bases and firefighting training centers that used foam employing the chemicals. State officials have written PFAS standards into water-discharge permits for the Suncor refinery in Commerce City after finding elevated levels.
Colorado health officials are also working with statewide sewage treatment agencies to establish a testing protocol for the biosolids resulting from wastewater treatment. The biosolids are usually spread as fertilizer on Eastern Plains farmland owned by the treatment agencies or local farmers, and the biosolids contain PFAS.
Dozens of Colorado cities and towns are also working with the state on plans to reduce PFAS contamination in their drinking water supplies, after the EPA’s sharp revision downward of guidance levels in June 2022. Some cities will have to spend tens of millions of dollars on new treatment plants with the equipment to filter out the most dangerous PFAS compounds. Even then, researchers have not yet agreed on safe ways to dispose of the used filters and other debris that will result.
The South Adams County Water and Sanitation District, anchored by Commerce City and serving 65,000 people, paid Denver Water $2.75 million last year for enough supply to dilute local well water tainted by the “forever chemicals” from firefighting foam runoff. The district needs $130 million to build a replacement plant with new equipment to take out PFAS and other chemicals, and is hoping for federal grants from the Bipartisan Infrastructure Law to make it possible.
The group of chemicals known as PFAS encompasses thousands of compounds used in consumer and industrial products. Produced since the 1940s, some versions do not break down over time and have been shown to contribute to human health problems including low birth weight babies, high cholesterol, compromised immunity, increased cancer risk and infertility.
For a study released in 2022, staff from the Colorado health department, the Colorado School of Mines, and Colorado Parks and Wildlife collected 49 fish across 10 species in the summer and fall of 2020. They sampled fish from Willow Springs Pond in Fountain, in El Paso County; Mann-Nyholt Lake in Henderson, in Adams County; and Tabor Lake in Wheat Ridge, in Jefferson County.
The sites were chosen in part because they are popular fishing spots where anglers often eat their catch. All of the fish contained a form of PFAS. State officials said at the time they did not have enough information to say whether consuming fish from those areas was a health threat.
The EWG study analyzed more than 500 samples of fish filets collected from 2013 to 2015. Measurements of the PFOS variety of the chemicals in one fish filet were equivalent to drinking water for a month at PFAS levels far higher than health guidelines, the researchers said.
The Colorado legislature last year passed a law phasing out sales of consumer goods containing PFAS over the next few years, joining a growing handful of states trying to influence manufacturers to cut off the stream of goods using “forever chemicals.” In addition, Colorado Attorney General Phil Weiser joined other states suing DuPont and other manufacturers of the chemicals in an effort to recoup cleanup funds .