An oily sheen shimmered along the Virginia side of the Potomac River this month. (Dean Naujoks / Potomac River Keeper)

If you’re in search of some locally sourced fish, be selective about what you choose to consume from the Potomac River.

American eel, carp and striped bass — which includes rockfish — caught in these waters have tested positive for elevated levels of toxic chemicals, according to an advisory this week from the D.C. Department of Energy and Environment.

Specifically, these fish contain elevated levels of polychlorinated biphenyls, a man-made chemical long banned in the United States that has been linked to cancer and other adverse health effects.

“Our goal is to protect the health and well-being of our residents,” the agency’s director, Tommy Wells, said in a statement. “This advisory helps ensure that residents who enjoy fish from District waters are aware of the health risks associated with consuming certain fish species.”

The advisory also suggests eating certain fish caught in city waters — sunfish, blue catfish, northern snakehead, white perch, largemouth bass, brown bullhead catfish and channel catfish — on a limited basis.

The city’s environmental agency has been monitoring contamination levels since 1980 and notes that improvements have been made along the way. Recommended maximum consumption levels of sunfish and largemouth bass, for instance, have more than doubled since the first advisory in 1994.

Read the full advisory here.

Courtesy of D.C.’s Department of Energy and Environment.