Scientists with NOAA’s Mussel Watch Program collected oysters from multiple sites in Chesapeake Bay this past winter as part of their larger effort to evaluate coastal water quality in the South Atlantic region.
Bivalve shellfish, such as oysters and mussels, serve as ideal indicators of chemical pollution. They tend to bioaccumulate pollutants from the large amounts of water they filter, they have limited mobility, and they are commonly found throughout the coastal zone.
The researchers will test the oysters sampled for nearly 600 chemical contaminants, including pesticides, pharmaceuticals, heavy metals, and per- and polyfluoroalkyl substances (PFAS). The team will then compare results to 2026 data from neighboring states, as well as to historic, nationwide data, to gain a better understanding of chemical contamination along the South Atlantic coast over time. Mussel Watch assessments are conducted on a five-year rotating schedule, with 2021 being the last year the region was sampled.
Chesapeake Bay is the largest estuary in the continental United States, with a watershed that covers over 64,000 square miles and provides critical habitats for wildlife and commercially important fisheries. However, centuries of land development and agricultural and industrial activities have added thousands of pollutants and excessive sediment to runoff, compromising water quality in the bay.
Bay managers can use Mussel Watch monitoring data to track the progress of contamination control efforts and to inform related management decisions. Data from the 2026 South Atlantic assessment will be available next year on NCCOS’ Coastal Pollution Data Explorer website.
Since 1986, the Mussel Watch Program has monitored U.S. coastal waters for chemical contaminants and biological indicators of water quality. The Chesapeake Bay oyster sampling work was conducted with the assistance of the Maryland Department of the Environment and the NCCOS Cooperative Oxford Laboratory and is authorized under Section 202, Title II of the Marine Protection, Research and Sanctuaries Act (MPRSA) (33 USC 1442).