State officials issued a “do not eat” advisory for all game fish on the Shenango River in Western Pennsylvania because of high levels of polychlorinated biphenyls (PCBs) found in fish.

Pennsylvania Department of Environmental Protection (DEP) Secretary Patrick McDonnell said in a statement the state found “extremely high levels” of the chemicals in routine tissue samples of fish taken this year. Smallmouth bass sampled from the river had PCB levels of 22 milligrams per kilogram, more than ten times the “No Consumption” advisory level of 1.9 mg/kg, the DEP said.

LISTEN: “Don’t Eat it: PCB Levels in Fish Prompt Advisory for PA River”

The state has previously issued advisories for bottom-dwelling fish like carp, muskie and channel catfish in the Shenango River, said DEP spokesman Neil Shader. But other species recently tested high in PCBs.

“This time around when we conducted sampling, we found it in more of the game species, so we wanted to make sure that we issued a sort of universal ‘do not eat’ advisory,” Shader said.

PCBs accumulate in the tissue, and can cause cancer and effect the immune, reproductive, and nervous systems, according to the EPA.

The advisory extends to all fish caught between the Shenango Lake Dam and the mouth of the Shenango River in New Castle, Pa. 

The Pennsylvania Fish and Boat Commission  will not stock trout in that section of the river until further notice.

“We are very concerned about the fate and effects of PCBs since they have an extremely long environmental half-life and will remain in the river for decades if not properly cleaned up and disposed of,” said fish and boat commission Executive Director John Arway, in a statement.

Shader said the state notified two drinking water providers with intakes along the affected stretch of the river: Aqua PA Shenango Valley, and Pennsylvania American Water in New Castle. But Shader said no PCBs have been found in drinking water so far.

“None of their monitoring has shown any sign of PCBs. All the tests came back as non-detect,” said Shader. “So there’s no concern for drinking water.”

The state has yet to determine the source of the contamination, but is investigating. 

The area of the river affected by the advisory in Lawrence and Mercer counties is near a Westinghouse superfund site in Sharon, Pa. that used PCBs until the 1970s to manufacture electrical transformers.