제주도 항내 퇴적물 중의 PCBs의 분포 특성

Abstract

Polychlorinated biphenyls (PCBs) were measured in surface sediments collected three times (June, October, December, 2013), inside Jeju Harbor, Seogwipo Harbor, Songsanpo Harbor, and Hallim Harbor (where a lot of steady shipping occurs) as major harbors of Jeju Island. From the results, their horizontal distribution and the correlation between PCBs concentrations and each of organic carbon and particle size distribution were examined. In addition, their levels were compared with the sediment quality guidelines applied in foreign countries for PCBs. The results obtained were summarized as follows: 1. The concentrations of PCBs inside Jeju Harbor, Seogwipo Harbor, Songsanpo Harbor, and Hallim Harbor, were in the range of 1.62∼4.45 (mean 2.65) ng/g , 0.84∼4.23 (mean 2.03) ng/g, 0.10∼0.44 (mean 0.24) ng/g, 0.17∼0.73 (mean 0.41) ng/g on a dry weight basis, respectively, decreased in the following sequences: Jeju Harbor> Seogwipo Harbor> Hallim Harbor> Songsanpo Harbor, and the levels were very low, as compared with those in other areas of the world. 2. In the analysis of PCBs homologue patterns, high-chlorinated PCB congeners (above hexa-chlorinated congeners) were dominant in surface sediments inside Jeju Harbor and Seogwipo harbor, indicating that their sources were originated from shipping activity. However, in surface sediments inside Songsanpo Harbor and Hallim harbor, it was difficult to assume their possible sources because of different patterns with the stations or their indistinctive patterns. 3. In the relationships between PCBs concentrations and organic carbon contents, the significant correlations (r2= 0.8337, 0.8532, 0.7466, 0.7723 for Jeju Harbor,Seogwipo Harbor, Songsanpo Harbor, and Hallim Harbor, respectively) were obtained, indicating that the distribution of PCBs was affected by the organic carbon. 4. In the relationships between PCBs concentrations and particle size (mud, sand and gravel) in surface sediments, PCBs concentrations were higher in the sediments with higher mud content, indicating that higher PCBs were distributed with increasing sediments of fine gradules. 5. The PCBs concentrations in surface sediments in this study were very low, compared with ER-L (effect range-low) and TEL (threshold effects level) among sediment quality guideleines (SQGs) applied in foreign countries, such as USA, Canada, and Australia, etc), indicating that their biological effects on the bottom organisms in marine environment were expected to be very low.