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 (429Kb)
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40,648,000 Yen (FY 1994 13,821,000 Yen)
To investigate the accumulation and behavior of toxic metals in the sediments, more than two hundred marine bottom surface and core sediments collected from the southeastern coastal margin of the Sea of Japan were analyzed for heavy metals and some other elements. Mercury is concentrated clearly in the uppermost layer of the core sediments, suggesting recent anthropogenic inputs. The vertical profiles of Pb and Zn in the core sediments are also through to be a result of recent environmental pollutions, and that of Mn is due to upward migration during early diagenesis. A supercritical fluid extraction(SFE) method using modified supercritical CO2 was developed for the simultaneous extraction of PCBs in sediments. The use of SFE is rapid, accurate and specific for the analysis of PCBs in environmental samples. The concentrations of organic halogens in the sediments and marine mammals were measured by neutron activation analysis. Organic halogen concentrations in the sediment samples from the Sea of Japan were lower than those in the sediment samples from the estuary of River Tama and the Bay of Osaka. It suggests that the sediments located at the Bay of Tokyo and Osaka were so much effected by human activities. Organic halogens in most of the mammal samples were greater than 50μg/g and especially high in the samples from the mid-latitude of the North Pacific, suggesting the influence of industrial activities. It was also found that an unidentified low molecular organic bromine compound showed a higher bioaccumlation potential than known compounds such as PCB and DDT. Characterization by GPC was conducted with organic halogens in sediment samples.
Marine Pollution, Sediment, Toxic Heavy Metals, Hazardous Chemical Substances, Unknown Pollutants