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Maryland Department of the Environment

Department of the Environment issues first fish consumption advisory for PFAS


Recommended limits issued for three species caught in Piscataway Creek as part of Maryland’s comprehensive response to risks

BALTIMORE (Oct. 15, 2021) – The Maryland Department of the Environment (MDE) has issued its first fish consumption advisory based on levels of a chemical compound in a class known as PFAS (per- and polyfluoroalkyl substances).

MDE issued guidelines for eating three species of fish caught in Piscataway Creek in Prince George’s County after sampling fish there and completing a scientific review of health risks posed by levels of PFOS (perfluorooctane sulfonate), one of the more widely studied PFAS chemicals. The recommended monthly limits are for redbreast sunfish and yellow bullhead catfish in the non-tidal portion of Piscataway Creek and largemouth bass in the tidal headwaters of Piscataway Creek.

“Maryland is committed to reducing the risks of PFAS chemicals in our state and continuing our close coordination with scientific, local, state and federal partners,” said Maryland Environment Secretary Ben Grumbles. “Our focus on PFAS in fish tissue and the resulting consumption advisory is another step forward in understanding, communicating, and reducing the potential for harm.”

Maryland has monitored levels of certain chemicals, including polychlorinated biphenyl (PCB) and mercury, in the state’s recreationally caught fish for decades. Findings from such monitoring are the basis for MDE’s fish consumption guidelines.

In fall 2020, MDE’s fish tissue sampling program began to include sampling for PFAS. 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. These 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.

The U.S. Environmental Protection Agency (EPA) has determined that exposure to PFOS over certain levels may increase the risk of developmental health effects during pregnancy or to breastfed infants as well as the risk of cancer, immune system damage or damage to the liver, thyroid or other organ systems.

MDE collected fish from routine monitoring, or core, stations. MDE also added two fish tissue sample locations in Piscataway Creek. MDE found elevated concentrations of PFOS in redbreast sunfish, yellow bullhead catfish and largemouth bass, leading to the new guidelines. MDE is also expanding sample collection in the larger Potomac area between fall 2021 and fall 2022.

In fall 2020, MDE began sampling of fish tissue for PFAS on the Eastern Shore, which includes stations in the Chester, Choptank, Corsica, Elk and Wicomico rivers and Isle of Wight and Chesapeake bays. The results from that sampling showed no levels of concern.

MDE is collecting additional, targeted monitoring for PFAS in certain specific water bodies that have been identified as having nearby potential sources of PFAS as well as sampling in locations known to be frequented by subsistence anglers and fishers. MDE will assess fish tissue sampling results for PFAS in specific waters and develop advisories when necessary to reduce human health risk.

MDE is putting a priority on the implementation of a science-based comprehensive plan for PFAS risk that is focused first on determining whether there are locations in Maryland where there are unacceptable risks to human health associated with exposures to PFAS and whether there are locations of continuing releases of PFAS compounds. Earlier this year, MDE released a report on a first phase of sampling of public drinking water systems across Maryland. A report on the results of a second round of sampling of additional public drinking water systems, and a third round of sampling is ongoing.

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