R/TX-2

Strategic focus area:

Description:

Per- and polyfluoroalkyl substances (PFAS) are environmentally persistent contaminants linked to adverse health outcomes in humans and wildlife. In Maryland's Chesapeake Bay and Coastal Bays, PFAS accumulation in sediments and biota, as well as their ecological impacts, remain poorly understood. This project will reconstruct multidecadal PFAS deposition histories using sediment cores, apply microbial community profiling to assess benthic ecosystem responses, and translate findings into practical guidance for aquaculture and environmental management. Sediment cores from selected sites in the Choptank River and Maryland Coastal Bays will be dated using 210Pb radiometric methods and analyzed for PFAS concentrations and geochemical indicators. Concurrently, sediment microbial communities will be characterized through 16S rRNA gene sequencing to reveal shifts in diversity and function under long-term PFAS exposure. Shellfish tissue PFAS levels will provide validation for sediment screening thresholds. This integrated approach will identify site-specific PFAS deposition patterns, link chemical accumulation with microbial and geochemical changes, and highlight implications for aquaculture, permitting, and sediment management. Key deliverables include PFAS baseline maps, a tiered sediment risk classification framework, stakeholder-friendly factsheets, and science-based decision-support tools. Engagement with Maryland Department of the Environment, Choptank Riverkeeper, and Envision the Choptank will ensure outputs are tailored to user needs. Findings will support regulatory, resource management, and aquaculture site planning decisions by offering a time-resolved view of PFAS contamination and its ecosystem impacts. This project will fill critical knowledge gaps in PFAS deposition trends and sediment microbial responses, advancing actionable science for coastal ecosystem resilience. It aligns with Maryland Sea Grant's Healthy Coastal Ecosystems focus area by integrating PFAS geochronology with microbial ecology and stakeholder-driven translation of research into practical applications for Chesapeake Bay and Maryland Coastal Bays.