(full paper is archived in the Miller Library)
Title: PCB and DDT residues in fishes of Elkhorn Slough and the Pajaro River, California
Student Author(s): Koenig, Walter D.
Location: Final Papers Biology 175H
Date: June 1971
Keywords: marine pollution
Abstract: Samples of fishes from theh Pajaro River and Elkhorn Slough were analyzed for chlorinated hydrocarbon residues. All DDT/PCB ratios for flesh and whole fish samples were less than 1.2; ratios were substantially greater than 1 in leopard shark liver samples. The possibility that the high concentration of DDT stored in the liver tissue is antagonistic to PCB storage is discussed. The percentage of total PCB content present in combined mono, di, and trichlorobiphenyls for the five species taken fro the Pajaro River was found ot exhibit a slight inverse relationship to the idealized trophic levels on which these fishes feed. PCB's more than DDT levels tended to increase in these same five fishes as one moved up theis simplified fraction of a food chain. Samples from the Pajaro River were compared to the same species captured in Elkhorn Slogh and found to have significantly greater PCB and DDT concentrations.