东平湖表层沉积物中多氯联苯来源初探

Spatial Distribution and Source Analysis of Polychlorinated Biphenyls (PCBs) in Dongping Lake

运用GC-μECD方法测定了东平湖表层沉积物16个采样点中7种指示性多氯联苯(PCBs)的含量,利用Arcgis10.2中IDW插值方法对多氯联苯的空间分布进行了分析,运用主成分分析法对东平湖多氯联苯的来源进行了探讨,结果表明:多氯联苯的含量为0~605.9 ng/kg;空间插值分析发现无论是多氯联苯总含量还是同系物的空间分布均呈现由大汶河入湖口向西北方向递减的趋势;东平湖表层沉积物中多氯联苯的同系物以高代氯为主,推测其来源为木材和煤炭的燃烧释放、进口电容器中多氯联苯的迁移、东平湖周围以及大汶河沿岸水泥厂和电炉炼钢厂产生的污染。研究多氯联苯与8种商业多氯联苯(PCBs)混合物(Aroclor)产品的单体质量占比进行主成分分析发现,其存在较大差异性,说明东平湖表层沉积物中多氯联苯的来源较为复杂。

The concentrations of 7 polychlorinated biphenyls at 16 sampling points’ surface sediment from Dongping Lake were determined by GC-μECD method. Arcgis10.2 IDW was used to determine the spatial distribution of PCBs and the source apportionment of PCBs in the surface sediment was conducted by principal component analysis(PCA). The results show that the concentrations of total PCBs range from 0 to 605.9 ng/kg. It finds out that both the total content and homologues of PCBs show a decrease tendency from the Dawen River to the northwest. Mean while, it finds out that the main part in surface sediment of Dongping Lake is higher chlorinated homologues of PCBs. It reveals that PCBs in the sediment mainly originates from leakage of capacitor, cement plants and electric furnace steelmaking plants around Dongping Lake and along the Dawen River. Moreover, the congener compositions of the sediment are different from known commercial Aroclors. This can explain that the source of PCBs in surface sediment of Dongping Lake is complex.