HA7 Evaluating Movement and Effects of POPs
Room 18C/D, Level 4
8:00 AM - 12:00 PM, Thursday, 13 November 2003
Chair: Johnson, Kevin ,
Co-chair: Letcher, Robert ,
(537) Evaluation of biota-sediment accumulation factors for PCB congeners in zooplankton and benthic infauna from the tidal Anacostia River, Washington, DC.
Foster, G1, Doelling Brown, P1, 1 George Mason University, Fairfax, VA, USA
ABSTRACT- The Anacostia River, a tidal freshwater tributary of the Potomac River, flows through the city of Washington, D.C. Because of the presence of persistent organic pollutants (POPs) in river sediments, it has been designated a Toxics Region of Concern by the EPA-Chesapeake Bay Program. Polychlorinated biphenyls (PCBs), representing a prominent group of POPs, are a primary cause of recreational fish consumption advisories issued for the tidal Anacostia River. Bioaccumulation of PCBs in the lower trophic organisms in the river was assessed to better predict the entry of PCBs in the aquatic food chain. Samples of water, sediment, benthic organisms, and zooplankton were collected from two locations in the river across multiple seasons and in multiple years. Congener specific PCBs were quantified using a gas chromatography-electron capture detection based method. Congener profiles for the various matrices were evaluated using principal components analysis (PCA), and accumulation factors were estimated for benthic organisms and zooplankton. Median concentrations of total-PCBs (tPCBs) in sediment at the two sites were 163 ng/g and 333 ng/g respectively, with corresponding median concentrations of 112 ng/g wwt and 90 ng/g wwt in the benthic organisms. The biota-sediment accumulation factor (BSAF) ranged from 0.87 to 2.51. Zooplankton accumulation factors were calculated based on tPCB concentrations in the particulate phase of the river water. Particle PCB concentrations at these sites were 13.2 ng/L and 8.9 ng/L, with corresponding concentrations in the zooplankton of 188 ng/g and 77 ng/g. The median zooplankton particulate accumulation factor (ZPAF) was 3.28. These empirically derived values correspond with accumulation factors estimated based on equilibrium partitioning theory (EPT), as well as values determined by previous investigations.
Key words: bioaccumulation factors, polychlorinated biphenyls, zooplankton, benthic infauna