大通湖表层沉积物中多环芳烃的含量、来源与生态风险评估

Concentrations,Sources and Ecological Risk Assessment of Polycyclic Aromatic Hydrocarbons in Surface Sediments from Datong Lake

为了解环洞庭湖区湖泊沉积物中多环芳烃（PAHs）的污染状况，2008年10月，选择典型内湖大通湖采集3个表层沉积物样品，采用加速溶剂萃取-高效液相色谱法测定了样品中美国环境保护局优先控制的16种PAHs。结果表明，大通湖表层沉积物中共检出9种PAHs，其含量在82～310μg/kg，平均185μg/kg。根据LMW/HMW、Phe/Ant和Fla/Pyr的比值判断，大通湖表层沉积物中的PAHs主要来源于煤炭、石油等化石燃料的不完全燃烧。大通湖各点位表层沉积物中w（PAHs）均低于ERL，更远低于ERM，生态风险较低。与国内其它湖泊（水库）相比，大通湖表层沉积物中PAHs的污染较轻。

In order to assess the pollution status of PAHs in surface sediments from lakes around Dongting Lake Area, three surface sediment samples from different parts of Datong Lake, a typical inner lake ,were collected in October 2008. The concentrations of 16 PAHs identified as priority pollutants by the US EPA, were measured using accelerated solvent extraction and HPLC. The results showed that nine PAHs were detected and their total concentrations were 82～310μg/kg,average 185μg/kg.According to the ratios of LMW/HMW, Phe/Ant and Fla/Pyr, PAHs in surface sediments from Datong Lake were assumed to come mainly from coal, oil and other fossil fuels incomplete combustion. The ecological risk of PAHs in the surface sediments from Datong Lake was low, as the concentrations of PAHs were lower than the ERL values, much lower than the ERM values. Comparing with other lakes’ PAHs level（reservoirs） in China, the pollution level of PAHs in surface sediments from Datong Lake was light.