太湖表层沉积物中多环芳烃的污染现状及来源分析

Distribution and sources of polycyclic aromatic hydrocarbons in surface sediments from Taihu Lake

为全面了解太湖表层沉积物中多环芳烃(PAHs)的污染状况,在太湖范围内采集了41处表层沉积物样品,利用气相色谱-质谱联用技术(GC-MS)对样品中16种优控多环芳烃进行了检测.结果表明,太湖表层沉积物中16种优控PAHs总量介于262.06—1087.22 ng·g-1之间,总体呈近岸高于湖心,东部高于西部.特征化合物指数分析显示太湖表层沉积物中PAHs以石油、煤、木材的燃烧为主,主成分分析(PCA)表明来自石油类物质高温燃烧产生的PAHs占总贡献的56%,煤及木材的燃烧占39%.ER-L及ER-M值表明太湖表层沉积物中PAHs并无严重的生态风险,但对部分化合物的潜在生态风险应该警惕.

Contents of sixteen priority polycyclic aromatic hydrocarbons （PAHs） in 41 surface sediment samples taken from Taihu Lake were analysed by GC-MS for understanding the PAHs pollution comprehensively. The results showed that the total concentration of 16 priority PAHs ranged from 262.06 ng-g-1 to 1087.22ng.g-1 , enriched mainly off the nearshore and gradually reduced towards lake central, east towards west. Characteristic values analysis of selected molecular indices indicated that the sources of PAHs in Taihu Lake surface sediments mainly originated from combustion of petroleum, coal and wood. The PCA analysis showed that 56% PAHs were from high temperature combustion of petroleum, and 39% PAHs were from combustion of coal and wood. The ER-L and ER-M indicated that there was no serious ecological risk of PAHs in Taihu Lake surface sediments, but attention should be paid to the potential ecological risk of some compounds.