The District of Columbia’s environmental health agency has issued its first fish consumption advisory based on the presence of PFAS, or “forever chemicals,” in fish caught in the rivers running through the nation’s capital. The advisory warns people who eat fish caught from portions of the Potomac and Anacostia rivers within the district to consider eating less or none of certain fish.
Issued in December, the advisory is based on fish tissue studies conducted by the district’s Department of Energy and Environment. For the first time, these studies tested for the presence of per- and polyfluoroalkyl substances, or PFAS, in addition to looking for PCBs (polychlorinated biphenyls), PAHs (polycyclic aromatic hydrocarbons), metals and certain pesticides. PCBs are also considered a “chemical of concern” in fish tissues taken from these same water bodies.
The group of synthetic substances known as PFAS are called forever chemicals because they do not break down in the environment. Instead, much like other chemicals that can be toxic to both humans and the environment, they tend to accumulate over time. Long-term exposure to PFAS, including by consuming foods containing the chemicals, can pose health risks such as cancer, liver problems and decreased immunity.
PFAS have for decades been widely used in a variety of industrial and consumer products, from firefighting foam to nonstick cookware, making it difficult to trace and address sources of the pollution in surface waters.
The U.S. Environmental Protection Agency has published draft criteria for limiting certain PFAS in waters that support aquatic life but doesn’t yet have final standards in place.
Studies are under way to better understand how much is too much when it comes to the ubiquitous chemicals. While federal drinking water standards for PFAS have been issued, the process of setting standards for fish consumption advisories can be even more complex.
The Department of Energy and Environment said its fish advisory notice for PFAS is “preliminary” because the EPA has not yet issued its final guidance “on how to interpret” concentrations of PFAS in fish tissue.
The district’s fish consumption warnings do not pertain to fish purchased from restaurants, supermarkets or fish vendors in the city.
For now, the agency advises the general public not to eat eel, carp, striped bass or largemouth bass from any DC waterway; to limit consumption of blue catfish to three servings per month; and to have no more than one serving per month of brown bullhead catfish, channel catfish, gizzard shad, smallmouth bass, snakehead, sunfish, white perch and yellow perch.
DOEE did not sample tissue from flathead catfish.
