太湖竺山湾湖滨带沉积物中多环芳烃分布、来源及风险评价

Distribution,Sources and Risk Assessment of Polycyclic Aromatic Hydrocarbons in Sediments from Zhushan Bay Littoral Zone,Lake Taihu

采用GC-MS联用技术分析了太湖竺山湾湖滨带10个点位和湖中心1个点位沉积物中16种US EPA优控多环芳烃（PAHs）的浓度。结果表明，16种多环芳烃的浓度为61.2~2 032.3 ng/g，平均浓度为1 131.5 ng/g。湖滨带点位以4环和5~6环多环芳烃为主，所占比例分别为28.6%和60.9%；湖中心点位以2~3环多环芳烃为主，所占比例为88.1%以上。湖滨带沉积物中多环芳烃主要来源为煤、石油等化石燃料的高温燃烧，而湖中心沉积物中多环芳烃主要来自油类泄漏污染。生态风险评价表明，湖滨带表层沉积物并不存在严重的多环芳烃生态风险，但是部分区域的某些多环芳烃浓度超过多效应区间低值（ERL），可能存在对生物的潜在危害，需加强生态风险防范。

Surface sediment samples were collected from lakeside zone of Zhushan Bay, Lake Taihu, of which 10 samples were collected from the littoral zone and one sample was collected from the center of the lake. The concentrations of 16 US EPA-priority-controlled polycyclic aromatic hydrocarbons （PAHs） were analyzed by GC-MS. The results showed that PAHs content varied from 61.2 to 2 032.3 ng/g, and the mean value was 1 131.5 ng/g. The spectra of PAHs showed that 4 rings and 5-6 rings were predominant ones in littoral zone, accounting for 28.6% and 60.9%, respectively, while 2-3 rings PAHs were predominant in the center of the lake, accounting for 88.1%. The source of PAHs in littoral zone sediments was mainly attributed to high-temperature combustion of coal, oil and other fossil fuels, but that in center of the lake was mainly attributed to oil spill. No significant PAH ecological risk was found in littoral zone of Lake Taihu according to ecological risk assessment. However, some PAH concentrations exceeded the effects range low （ERL） in some sampling sites. Potential harmful effects on organisms might exist, and ecological risk should be prevented.