Groundwater on military bases along the Chesapeake Bay is contaminated with toxic PFAS “forever chemicals” at levels many times above the level some regulators say is safe for drinking, and they are probably ending up in blue crabs, oysters and other marine life that are consumed by humans.
The Chesapeake Bay holds a diverse ecosystem that stretches about 200 miles from northern Maryland to southern Virginia, and is among the world’s most productive estuaries. Its brackish saltwater is renowned for shellfish like oysters and blue crabs, the latter of which largely drives the state’s $600m seafood industry, which sends its catch across the globe.
But the Chesapeake is also home to the US Naval Academy and more than a dozen other military installations, and public health advocates suspect the PFAS contamination largely stems from firefighting foam used to extinguish fires or during training exercises.
The Environmental Working Group analysis compiled Department of Defense data from nine bases along the bay, revealing levels as high as 2.25 million parts per trillion (ppt). Some states have set safe drinking water levels for individual PFAS compounds as low as 1 ppt.
The contamination presents an “extremely troubling” health threat in the nation’s largest estuary, said Scott Faber, EWG’s senior vice president for government affairs.
“We’ve seen higher levels in water, but not many … and it strikes at the heart and, perhaps more importantly, the stomach of everyone who comes from this part of the world,” Faber said.
PFAS, or per- and polyfluoroalkyl substances, are a class of about 9,000 compounds used to make products water, stain or heat resistant. They’re also commonly found in food packaging, clothing and carpeting, and are often dubbed “forever chemicals” because they do not naturally break down.
The compounds are linked to cancer, birth defects, liver disease, thyroid disease, decreased immunity, hormone disruption and a range of other serious health problems.
EWG identified groundwater contamination at every base that has tested for the chemicals, and frequently at levels that are considered extremely high.
The groundwater is hydrologically connected to the bay, and state studies of Hog Point oysters harvested from near Maryland’s Patuxent River Naval Air Station found PFAS levels in the meat as high as 1.1m ppt. A 2020 study conducted in the same area by Public Employees for Environmental Responsibility (PEER) found PFAS levels in striped bass at more than 23,000 ppt, crab meat at about 6,000 ppt and oysters at more than 2,000 ppt.
Though the federal government has failed to set limits for PFAS in food, the levels are “very disturbing”, said Tim Whitehouse, PEER’s executive director, and especially a threat to pregnant women.
“This shouldn’t be in our environment and we shouldn’t normalize this, because we know these chemicals are very dangerous,” he said.
PFAS were also found to be contaminating some of the region’s municipal drinking water and private wells, though the extent is unclear. PFAS levels in waters further from the bases also aren’t known.
The DoD has proposed a 30-year timeline for cleaning up PFAS contamination at hundreds of bases across the US, but little progress has been made in the Chesapeake.
“They haven’t really started cleaning it up at this point,” said Jared Hayes, EWG’s policy analyst.
In the meantime, there’s little that consumers can do to protect themselves beyond exercising caution, Whitehouse said.
“I wouldn’t say don’t eat seafood, but you need to be cautious about it and watch your consumption patterns,” he said. “Unfortunately so little is known about the extent of the contamination and what levels are harmful to human health that it creates this big uncertainty, and the government needs to step in and do its job.”
