MP12 Organic, Metallic, Organometallic Pollutants
Monday, 14 November 2005: 8:00 AM - 6:30 PM in Exhibit Hall

(PHE-1117-716967) Identification of PCB, PAH and Chlordane Source Reaches in the Anacostia River Watershed, MD/DC.

Phelps, H¹, ¹ University of the District of Columbia, Washington, DC, USA

ABSTRACT- The freshwater Anacostia River estuary of Washington, DC is one of three Areas of Concern in the Chesapeake Bay. It has a fishing advisory for PCBs and chlordane and a depauperate benthos with high tumor incidence in resident fish. Two-week active biomonitoring with Corbicula fluminea clams has been found effective and was used to assess significant levels of bioavailable EPA Priority Pollutants and six metals in first and second order tributaries of the Anacostia River watershed. Clams placed in one tributary (Lower Beaverdam Creek) had significant PCB and Aroclor accumulation starting at the highest of several industrial centers. High PAH bioaccumulation was found at many sites in the Northeast Branch with greatest concentrations associated with three industrial centers. High chlordane bioaccumulation was found at only one second-order stream of the Northeast Branch which was not associated with any industrial center. Clams placed in the Northwest Branch had no significent bioaccumulation of pesticides, PCBs or PAHs. No significant pollutant bioaccumulation was found in the Beltsville Agricultural Center drainage. No metal levels exceeded control levels in nearby Potomac River clams. All of the most contaminated watershed sites except two were located in the Maryland counties around DC.

Key words: watershed, PCB, PAH, Anacostia