Polycyclic and organochlorine hydrocarbons in sediments of the northern South China Sea.

Mar Pollut Bull. 2018 Dec;137:668-676. doi: 10.1016/j.marpolbul.2018.10.039. Epub 2018 Nov 15. Kaiser D1, Schulz-Bull DE2, Waniek JJ3. Author information 1 Leibniz Institute for Baltic Sea Research Warnemünde, 18119 Rostock, Germany. Electronic address: david.kaiser@io-warnemuende.de. 2 Leibniz Institute for Baltic Sea Research Warnemünde, 18119 Rostock, Germany. Electronic address: detlef.schulz-bull@io-warnemuende.de. 3 Leibniz Institute for Baltic Sea Research Warnemünde, 18119 Rostock, Germany. Electronic address: joanna.waniek@io-warnemuende.de. Abstract We investigated the concentration distribution and composition of organic pollutants in sediments of the shelf and the deep northern South China Sea (NSCS). Concentrations of polycyclic aromatic hydrocarbons (Σ15PAH; 10.69-66.45 ng g-1), Dichlorodiphenyltrichloroethane (Σ4DDT; 0-0.82 ng g-1), and polychlorinated biphenyls (Σ24PCB; 0-0.12 ng g-1) are below established sediment quality guidelines, suggesting no environmental risk. Surprisingly, concentrations increase from the shelf to the deep NSCS, and are higher in the east of the study area. The organic pollutant composition indicates PAH mainly derived from pyrogenic sources, and mostly degraded DDT and PCB. However, in the deep NSCS, considerable contribution of petrogenic PAH, low chlorinated PCB and p,p'-DDT suggest more recent input from different sources compared to the shelf. From these results we infer that organic pollution in the NSCS does not originate from the Pearl River Estuary but from the NE SCS, SW of Taiwan. KEYWORDS: Organic pollution; Sediment; Source appointment; South China Sea