PH11 Bioaccumulation and Biotransformation of POPs
Exhibit Hall
8:00 AM - Thursday, 13 November 2003
(PH119) NOAA's National Status and Trends Program in Galveston Bay: Chlorinated hydrocarbons in oysters, 1986-2001.
Sericano, J.1, Wade, T.1, Brooks, J.2, Ramirez, J.2, Qian, Y.1, 1 Geochemical and Environmental Research Group - Texas A&M University, College Station, Texas, U.S.A.2 TDI-Brooks International/B&B Laboratories, College Station, Texas, U.S.A.
ABSTRACT- The Galveston Bay system constitutes one of the most economically important estuaries along the northern coast of the Gulf of Mexico. For many years now, this area has been the recipient of various environmental contaminant inputs because of its aggressively growing urban and industrial development. For this reason, the National Oceanic and Atmospheric Administration (NOAA) selected to monitor the levels of organic contaminants in bivalves from Galveston Bay as part of NOAA's National Status and Trends Mussel Watch (NS) Project. Since 1986, the NS Project has been monitoring, on a national scale, the spatial and temporal trends in the concentrations of selected trace organic and inorganic contaminants through the annual collection and analysis of bivalve mollusks. The chlorinated hydrocarbon data produced between 1986 and 2001 for six sampling locations in Galveston Bay (Houston Ship Channel, Yacht Club, Todd's Dump, Offatts Bayou, Confederate Reef, and Hanna Reef) are presented. Average total DDT concentrations for the entire study ranged from 12.8±7.98 ng/g (Hanna Reef) to 120±53.2 ng/g (Ship Channel). Similarly, average total chlordane concentrations and total PCBs ranged from 7.32±4.26 ng/g (Confederate Reef) to 102±55.9 ng/g (Offatts Bayou) and from 57.2±25.9 ng/g (Hanna Reef) to 833±352 ng/g (Ship Channel), respectively. Trends in concentrations of these contaminants with time were not obvious. The highest concentrations are generally encountered in locations closer to urban areas while the lowest levels are found in relatively isolated locations within Galveston Bay. When these concentrations are compared to other locations in the Gulf of Mexico, Ship Channel and Yacht Club are ranked in the top 10% of the most contaminated locations followed closely by Todd's Dump and Offatts Bayou in the top 20%. Only Hanna Reef and Confederate Reef, with the exception of total PCB concentrations, are ranked with cleaner locations in the Gulf of Mexico (i.e., lower 50%).
Key words: pcbs, chlorinated pesticides, oysters, Galveston Bay