Distributions of Sedimentary POPs (Persistent Organic Pollutants) in Tokyo Bay - Results from the Survey of POPs in Tokyo Bay in 2002.
In 2002, vertical and horizontal distributions of POPs in Tokyo Bay were surveyed by Hydrographic and Oceanographic Department, Japan Coast Guard. The samples were analyzed about thirteen kinds of POPs. The sedimentation dating of core samples were analyzed based on 210Pb measurements. In the horizontal distributions of POPs, most of substances show the highest concentration points on the head of the bay, next higher points were on the entrance of the bay, and the lowest points were near the Nakano-se and Uraga-Suido traffic routes. The concentrations of each substance on the head of Tokyo Bay were compared. PCBs and most of the substances show the higher concentration in the west part than the east part of the bay. On the other hand some components of Dioxins, PCDDs and PCDFs, show the higher concentrations in the east part than the west part. Characteristics of these surface distributions are considered to be related to the source of the substances and/or the sedimentation environment such as the grain size. Historical trend of POPs was considered from the vertical distributions of POPs’ concentration. The concentrations of PCBs and most of the substances began rising at 1950s, showing the peak near 1970, and then lowering until today. The concentration of Chlordanes showed the peak at 1980s, and relatively high concentrations were kept until today. The concentration of HCB began rising at 1950s, and relatively high concentrations were kept until today. The historical trends of the concentrations were considered to be reflected the terms of use and/or discharge of each substance.
| Main Authors: | , , , , , , , , , |
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| Format: | Journal Contribution biblioteca |
| Language: | Japanese |
| Published: |
2005
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| Online Access: | http://hdl.handle.net/1834/15722 |
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