낙동강 하천 및 호소 퇴적물에서의 PAHs, OCPs, Co-PCBs 농도 분포와 발생원 평가

We investigated the levels and distribution patterns of 16 priority polycyclic aromatic hydrocarbons (PAHs), 12 Coplanar polychlorinated biphenyls (Co-PCBs) and organochlorine pesticides (OCPs) in the surface sediments from the Nakdong river basin, Korea. The levels of 16 PAHs and 12 Co-PCBs in the river sediment samples ranged from not detected (N.D.)~969.3 ng/g-dry, 4.2~7716.5 pg/g-dry (0.0~10.1 pg-TEQ/g-dry), respectively. Also, the levels of 16 PAHs were from 5.8~2987.2 ng/g-dry and 4.3~461.1 pg/g-dry (0.0~0.6 pg-TEQ/g-dry) for 12 Co-PCBs in the lake sediment samples. Only dichloro-diphenyl-trichloroethane (DDT) were detected among target OCPs and the concentration ranged from N.D.~1.5 ng/g-dry in the river sediment samples. These contamination levels were far below the guideline values suggested for environmental quality assessment. Low molecular weight PAHs were dominant in the river sediment samples, while middle and high molecular weight PAHs were dominant among 16 PAHs in the lake sediment samples. PCB-118 and PCB-105 were predominant congeners in the sediment, which were similar to the results obtained from previous studies. With these results, the assessment of potential sources of PAHs and Co-PCBs contamination in the sediments of the Nakdong river basin was performed. The pyrogenic-PAHs originated from combustion of fossil fuel and biomass were related with the PAHs contribution in most of the sediment samples, and Co-PCBs in the sediment samples were related with commercial PCB products.