太湖流域水源地多氯联苯分布特征与污染水平

为系统了解太湖流域主要水源地多氯联苯(PCBs)的污染现状,于2012年3月和6月分别采集水相、悬浮颗粒物和沉积物样品,并利用气相色谱-质谱联用仪(GC-MS)对PCBs的浓度进行了分析。结果表明,3月水相、悬浮颗粒物和沉积物中均未检测出PCBs类物质。6月水相中PCBs质量浓度在ND~1.04 ng·L~(-1)之间,平均值为0.57 ng·L~(-1),悬浮颗粒物和沉积物中PCBs质量浓度分别在0.96~2.72 ng·g-1和0.47~1.29 ng·g-1之间。Aroclor 1016和Aroclor 1260在3种介质中均有检出,且Aroclor1016浓度均为最高。与国内外研究相比较,太湖流域主要水源地PCBs污染水平较低。水相中PCBs浓度水平低于我国地表水环境质量标准;悬浮颗粒物和沉积物中PCBs浓度水平均低于加拿大保护水生环境沉积物化学品风险评价标准的LEL值,说明各样点PCBs对底栖动物无毒性影响。

Distribution Characteristics and Pollution Level of PCBs in Water Source Area of Taihu River Basin

In order to systematically investigate the pollution status of Polychlorinated biphenyls (PCBs) in major water source area of Taihu River Basin, water samples, suspended particulate matter and sediment samples were collected in March 2012 and June 2012, respectively. Then samples were analyzed by gas chromatography-mass spectrometry (GC-MS) to investigate the concentration of PCBs. The results showed that, in March, there were no PCBs in water, suspended particulate matter and sediment. In June, the concentration of PCBs in the aqueous phase was between ND and 1.04 ng·L-1, with an average of 0.57 ng·L-1. The concentration of PCBs in suspended particles and sediments was between 0.96 to 2.72 ng·g-1 and 0.47 to 1.29 ng·g-1, respectively. Aroclor1016 and Aroclor 1260 were detected in all kinds of medium, and the concentrations of Aroclor1016 were the highest. Compared with the domestic and foreign researches, the pollution level of PCBs was lower in water source area of Taihu River Basin. The concentration of PCBs in the water phase was lower than environmental quality standards for surface water in China. The concentration of PCBs in suspended particulate matter and sediments were lower than the LEL value of risk assessment criteria for aquatic chemicals in Canada, which indicates PCBs has no toxic effect on benthic animals at each sampling site.