Occurrence and Characteristics of Organochlorin pesticides and PCBs in Yellow Sea

Abstract

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) are important persistent organic pollutants (POPs). Their persistency, bioavailability, high toxicity and long range atmospheric transport have aroused global concern since 1960s. Hence, an international treaty, Stockholm Convention, was adopted to protect human health and the environment from persistent organic pollutants (POPs) in 2001, and entered into force in 2004. The convention nominated 12 compounds (aldrin, dieldrin, endrin, chlordane, heptachlor, HCB, DDTs, toxaphene, mirex, PCBs, dioxins, and furans) as high priority POPs. To assess the contamination status and distribution characteristics of persistent organochlorine pollutants in the Yellow Sea, we collected samples of various environmental matrixes such as sediment, seawater, and air on board R/V Eardo in September 2004 and October 2005, and analyzed 22 OCPs and 89 PCB congeners. Sampling covered half of the continental self system of the Korean side, including a dumping zone ‘Byung’. OCPs and PCBs were detected in all the matrixes from Yellow Sea. Among 87 surface sediment sampling sites, 3 or 4 sites showed PCBs, DDTs, and chlordane concentrations exceeding the effect range low (ERL) values for benthic organisms which is suggested by Long et al. (1995). All sites above the ERL values of PCBs, DDTs, and chlordanes are located in the dumping site ‘Byung’, implying that a dumping site could be a source of POPs in the Yellow Sea. However, all the concentrations are lower than the effect range median (ERM) values of each chemical. Except for 2 or 3 dumping sites, OCPs and PCBs are homogeneously distributed in the Yellow Sea. The general concentration of PCBs, DDTs, and chlordanes are relatively lower than those from Korean coastal regions; however HCH concentrations showed similar level. Among the target organochlorine compounds, PCBs, DDTs, and HCHs were major contaminants in this region. But their compositions are diverse accordi