环太湖河流沉积物中PAHs的空间分布、毒性及源解析

Spatial Distribution, Toxicity and Source Apportionment of PAHs in Sediments from Rivers Around Taihu Lake

对环太湖41条河流表层沉积物中16种美国环保署优先控制的PAHs含量进行了检测,并分析了其空间分布、毒性和来源。结果表明:沉积物中PAHs浓度范围为382.5~2 268.7 ng·g-1,平均值为1 056.6 ng·g-1,其中TEQBa P的浓度为36.3~224.0 ng·g-1,平均值为98.8 ng·g-1;PAHs浓度的高值区出现在太湖西北部河流,其中龙游河(TR8)最高,漕桥河(TR10)次之。利用分子比值法和正定矩阵模型(PMF)对PAHs的来源进行定性和定量分析可知,汽油、柴油燃烧对环太湖河道表层沉积物中PAHs贡献最大(44.6%),其次为煤炭燃烧(39.1%)和生物质燃烧(16.3%);使用PMF-TEQ(正定矩阵模型和毒性当量)定量计算3种源对PAHs毒性(TEQBa P)的贡献,结果表明化石燃料燃烧的贡献最大。

In this study, the concentrations of 16 US EPA priority PAHs were analyzed from 41 sediment samples collected from rivers around Taihu Lake, and their distributions, sources and ecological risks were further investigated. The total concentrations of PAHs ranged from382.5~2 268.7 ng·g-1with a mean value of 1 056.6 ng·g-1, while TEQBapvaried from 36.3~224.0 ng·g-1with an average of 98.8 ng·g-1. The sample in Longyou River(TR8)had the highest concentration of PAHs, followed by Caoqiao River(TR10), which are located to the north of Taihu Lake. The major contributors to total PAHs in sediments were gasoline and diesel combustion(44.6%), followed by coal combustion(39.1%), and biomass combustion(16.3%). The fossil fuel combustion was the greatest contributor to the toxicity of PAHs in river sediments.