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Résumé :
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As part of a program to investigate the levels, fate and bioaccumulation of organic contaminants in a polluted marine harbor, organochlorine compounds including the polychlorinated biphenyls (PCBs), dichloro diphenyltrichloroethane and metabolites (DDTs), chlordanes, dibenzo-p-dioxins (Ds) and dibenzofurans (Fs), polycyclic aromatic hydrocarbons (PAHs) and sulphur heterocycles were analysed in sediments spiked with St. John's Harbor sludge. Winter flounder (Pseudopleuronectes americamus) were exposed to these sediments containing six levels of harbor sludge during four winter months. Following exposure, sediments were reanalysed to investigate the persistence of the contaminants. The primary contaminants detected were PAHs (similar to 5000 ng/g), predominantly alkylated phenanthrenes, fluoranthene and pyrene; PCBs with a predominance of Aroclor 1260 signature (similar to 64 ng/g), DDTs (similar to 5 ng/g), hepta and octachloro dioxins and furans (similar to 0.5 ng/g) with very row levels of less chlorinated congeners. The PAHs degraded with an estimated half life of 2 to 3 months, while no significant degradation could be attributed to the other compounds. Bioaccumulation to muscle showed the potential uptake of contaminants in biota inhabiting the harbor.
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