M1 AM Delaware River/Bay
Monday, 14 November 2005: 8:00 AM - 11:40 AM in Ballroom 1

(FIS-1117-745971) Distribution of Organic Compounds and Trace Elements in Fish Tissue and Streambed Sediment in the Delaware River Basin, Pennsylvania, New Jersey, and New York, 1998-2000.

Fischer, Jeffrey¹, Romanok, Kristin ¹, Brightbill, Robin², Riva-Murray, Karen³, Bilger, Michael², ¹ U.S. Geological Survey, Trenton, NJ, USA² U.S. Geological Survey, New Cumberland, PA, USA³ U.S. Geological Survey, Troy, NY, USA

ABSTRACT- From 1998 to 2000, the U.S. Geological Survey collected fish-tissue samples at 25 sites and streambed-sediment samples at 35 sites throughout the Delaware River Basin to determine the distribution of organic compounds and trace elements in streams in different land-use settings. The most frequently detected contaminants in fish tissue were mercury, DDTs, polychlorinated biphenyls (PCBs), chlordanes, and dieldrin. Detection frequencies ranged from 100 percent for mercury to 60 percent for dieldrin. U.S. Fish and Wildlife Service guidelines for the protection of fish-eating wildlife were exceeded most frequently by mercury and PCBs (at 84 and 52 percent of sites, respectively). Concentrations of PCBs, chlordanes, and dieldrin increased with the percentage of urban land in a basin, and the wildlife guidelines for these compounds were exceeded most frequently in urban basins. The most frequently detected organic compounds in streambed sediment were DDTs, polycyclic aromatic hydrocarbons (PAHs), phthalates, PCBs, chlordanes, dieldrin, and phenols. Detection frequencies ranged from 80 percent for DDTs to 54 percent for phenols. All eight trace elements analyzed for were detected at 97 percent of the bed-sediment sites. The Probable Effect Concentration (PEC), the threshold above which adverse biological effects frequently occur, was exceeded most frequently by lead, chromium, zinc, PAHs, chlordanes, and nickel (at 26 to 16 percent of the sites). Arsenic, cadmium, copper and dieldrin concentrations exceeded the PEC at about 5 percent of the sites. Arsenic concentrations were highest in the Coastal Plain, and concentrations of cadmium and zinc were elevated in regions where coal had been mined in the past. Concentrations of many contaminants in sediment increased with the percentage of urban land in a basin, and the PEC was exceeded most frequently in urban basins. Mercury, cadmium, zinc, PAHs, and phthalates were detected more frequently and at higher concentrations in forested basins than in agricultural basins.

Key words: contaminants, sediment, tissue