New fish consumption advisory from Maryland warns of PFOS exposure in Conococheague fish

08 December 2023- The Maryland Department of the Environment has issued a new fish consumption advisory for certain locations based on levels of a chemical compound in a class known as PFAS (per- and polyfluoroalkyl substances) for 15 fish species found in Maryland waterways.

Washington County’s advisory can be found HERE, with the state advising that children should not consume most bass from the Conococheague Creek due to increased exposure of the fish to PFOS chemicals.

“Fish is an important part of a healthy diet, but it is important to share what we’ve learned to help people—including subsistence anglers in underserved communities— make informed decisions about what they and their families eat,“ said Maryland Department of the Environment Secretary Serena McIlwain. ”Maryland is committed to informing the public, following the science, and providing data as part of our comprehensive response to PFAS as an emerging national concern.” 

Though the vast majority of fish from Maryland waters may be eaten in moderation, the advisory provides updated guidelines for recommended consumption for certain recreationally-caught fish species in Maryland’s fresh, estuarine, and marine waters.

PFAS refers to a group of more than 4,000 human-made chemicals that have been used since the 1940s in a range of products, including stain- and water-resistant fabrics and carpeting, cleaning products, paints, cookware, food packaging and fire-fighting foams. The uses have led to PFAS entering the environment, where they have been measured in soil, surface water, groundwater and seafood. Most people have been exposed to PFAS because of its use in so many common consumer goods.

Fish consumption advisories provide recommended limits on how often certain fish may be eaten to help minimize health risks. Consumption guidelines offer recommendations on the number of meals per month by species for the general population, women of childbearing age, and children. If a person were to eat more than the recommended meals every month for 30 years, then they have an increased risk of 1 in 10,000 of having a health outcome due to that level of consumption.

Of the species with a new PFAS-based advisory, large and smallmouth bass (13 advisories), sunfish, including bluegill (12 advisories) and white perch (11 advisories) had the highest numbers of advisories based on location and accounting for more conservative recommendations for women of childbearing age and children. None of the results from this round of PFAS sampling led to an advisory for all populations to completely avoid any fish from any Maryland waterway. Testing revealed no PFAS levels of concern or need to recommend meal limits for blue crabs or oysters.

A previous round of testing and resulting advisories for meal limits based on PFAS were issued in 2021 for three species of fish caught in Piscataway Creek in Prince George’s County. 

Maryland has monitored levels of certain chemicals, including polychlorinated biphenyl and mercury, in the state’s recreational fishing for decades. Findings from such monitoring are the basis for the department’s fish consumption advisories. Surveillance will continue as needed.