Distribution And Ecological Risk Assessment Of SVOCs In Surface Sediments From Taihu Lake

As China's second largest freshwater lake,Taihu lake located at the junction between Jiangsu and Zhejiang provinces. It play an important role in water traffic. In recent years, affected by coastal agricultural and industrial development and the impact of human activities, pollution situation of Taihu Lake becomes worse day after day. As the research object in this paper about lake region (31°00'～31°30'N,120°00'～120°25'E), we had analyzed for organic pollutants in water and surface sediments samples which were collected from Taihu Lake and done ecological risk assessment with reference to the relevant evaluation method.The main conclusions are:1. There are 10 kinds of organic pollutants detected in water samples of Taihu Lake, including:Naphthalene,2-Methyl naphthalene,Phenanthrene, Fluorene, Fluoranthene, Pyrene, Dimethyl phthalate, Dinbutyl phthalate, Dibenzofuran, their distribution are obviously regional.In addition to 2,4-Dinitrotoluene, the other pollutants did not exceed the "Surface Water Environmental Quality Standard"(GB3838-2002).The risk assessment of organic pollutants in water samples from Taihu Lake were evaluated by using quotient method and the effect of extrapolation discribed in EU risk assessment guidelines(TGD). The results showed that pollutants in water did no threat to the environment except Phenanthrene. In addition, Fluoranthene, Pyrene and Dibenzofuran have slight ecological risk.2.6 classes 23 species organic pollutants in sediments of Taihu Lake were reported:PHAs(12), Esters(5), Substituted Aromatic Compounds(2), Phenols(2), Furans(1) and Ketones(1). The distribution of these compounds in sediments are similar in water showing significantly regional. With mSQG-Q and species sensitivity distribution method for ecological risk assessment about polycyclic aromatic hydrocarbons in sediments of Taihu Lake, evaluation results are basically consistent. It is showed that serious ecological risk does not exist in Taihu lake. Fluorine and Phenanthrene may have a little ecological risks in local place of Taihu Lake.