High levels of “forever chemicals” have been reported in freshwater fish and water from a Maryland creek, raising new questions about the extent and seriousness of these compounds’ contamination in the Chesapeake Bay watershed.
Per– and poly-fluoroalkyl substances, or PFAS, were found in the blood plasma of smallmouth bass taken in 2018 from Antietam Creek near where it flows into the Potomac River, according to Vicki Blazer, a biologist with the U.S. Geological Survey’s Leetown Science Center in Kearneysville, WV.
PFAS compounds also were detected — though at lower levels — in the plasma of the popular gamefish in three other locations: the South Branch of the Potomac in West Virginia and at two sites in the Susquehanna River in Pennsylvania.
PFAS are a group of more than 4,700 chemicals that have been used for decades in a wide variety of products, including nonstick cookware, stain– and water-repellant fabrics and fire-fighting foams. They are very persistent — hence their nickname — and have been found across the United States in groundwater and surface water, in fish and other foods, as well as in people’s bodies.
The extent of PFAS contamination reported in the six-state Chesapeake Bay watershed has been fairly limited — about 20 sites, many of them connected with military bases or airports where fire-fighting foam has been sprayed. But testing to date also has been limited, though Pennsylvania and Maryland are expanding their search for the compounds in drinking water supplies.
The USGS data are the first reports of PFAS contamination in finfish in the Bay watershed, though a 2002 study reported finding the compounds in oysters at the mouth of the Patuxent River. The Maryland Department of the Environment is checking for PFAS in oysters from that site and from the St. Mary’s River.
Animal studies have found that exposure to high levels of some PFAS can affect growth and development, reproduction, thyroid function and the immune system, as well as injure the liver. Just as they’ve been found in many people, PFAS also have been widely detected in wildlife and fish, where their effects on those animals are less well-known. But PFAS bioaccumulate, meaning they can build up in people who eat contaminated fish and wildlife.
Blazer said the levels measured in the Antietam Creek bass were high compared with what she’d seen in scientific literature. A Canadian lab commissioned by the USGS to analyze the blood plasma samples detected six different PFAS compounds. Levels of one — perfluorooactane sulfonate, or PFOS — measured as high as 574,000 parts per trillion. The average PFOS level among all 34 bass plasma samples was 381,000 parts per trillion.
PFAS levels in fish tend to be highest in their blood and livers, Blazer said, with much lower levels in their muscle or tissue, which is what’s typically converted for fillets.
‘So what we’re eating tends to be lower [in PFAS] than in the plasma,” the USGS scientist said.
“We don’t know what it means to the fish yet,” she added. But it’s become one more possible factor in the health problems she’s been studying for more than a decade in the watershed’s smallmouth bass, including abnormal sexual organs, skin lesions, die-offs and poor reproduction.
Research suggests several factors could be involved in the species’ declining abundance in the watershed, including abnormally high river flows during the spring spawning season. But Blazer and her team have identified other possible culprits, including bacteria and viruses, parasites and hormone-altering chemicals that can suppress a fish’s immune system.
“It does look like [PFAS] might be another risk factor for the immunosuppression we see,” Blazer said. She’s having plasma analyzed from fish collected in other years to see if they also show PFAS contamination.
Brent Walls, the Upper Potomac Riverkeeper, called the PFAS levels in bass plasma from Antietam Creek “astronomical” and “very troubling.” Anglers fishing for sport often release smallmouth bass, he said, but many also are consumed.
The riverkeeper said the USGS data prompted him to look for possible sources of PFAS contamination in Antietam Creek. He hired a Pennsylvania laboratory to analyze water samples he collected from outfalls for wastewater treatment plants serving Hagerstown and Smithsburg. He also sampled water near the mouth of the creek for a comparison.
The lab reported detecting a total of 11 different PFAS compounds at the three sampling sites. The lab measured a cumulative 138 parts per trillion in treated wastewater at Hagerstown, 82 parts per trillion at Smithsburg, and only 7 ppt at the creek’s mouth.
The U.S. Environmental Protection Agency does not regulate PFAS, though it has said it’s moving toward doing that for a handful of the compounds. It did set a “health advisory level” in 2016 for drinking water of 70 parts per trillion for two compounds, PFOS and PFOA, or perfluorooctanic acid.
Levels of PFOS and PFOA in the riverkeeper’s water samples did not exceed the EPA recommended level for drinking water. But Walls noted that PFAS can build up in animals and people if they ingest it repeatedly over time.
“There’s just a lot of unanswered questions about levels,” he said. “What’s the toxic level in drinking water? What’s the level in fish consumption? What’s good and what’s not good?”
He said he was also worried that contaminants might be in sewage sludge from wastewater plants, which gets spread as fertilizer on farm fields.
Walls said he had presented his and the USGS data to the Maryland Department of the Environment earlier this year but was frustrated by the agency’s lack of response to date.
A number of states, likewise frustrated by the EPA’s failure to regulate PFAS, have set or are considering setting much lower limits on PFAS in their drinking water. Pennsylvania is among them. With about 30 contaminated water supplies reported across the state already, the Department of Environmental Protection began testing for PFAS last year in about 400 other locations statewide where it believes contamination is possible.
The MDE spokesman said agency officials have reviewed the Antietam Creek information and hope to have a conference soon with the riverkeeper. Apperson said officials want to know more about how he collected the water samples and the basis for his conclusion about health risks associated with PFAS in fish blood.
Walls welcomes the scrutiny. “Everything was by the book … our sampling program is pretty solid,” he said. Meanwhile, he said he hopes that Maryland officials will be prompted to do their own research and protect the public.
“It’s pretty much up to the states to start doing this, because the federal government is dragging their feet for sure,” he said.
By Tim Wheeler