济南市道路尘中类二噁英类多氯联苯残留情况

通过采集济南市区主要路段道路尘样品,用气相色谱-电子俘获检测器(GC-ECD)方法分析了济南市区主要路段道路尘中毒性较高的12种类二噁英类多氯联苯(DL-PCBs)的残留情况,并对样品中DL-PCBs的含量、污染水平及同系物的组成进行了详细研究。结果发现,DL-PCBs在各采样点均有检出,残留总浓度在0.20～22.84ng/g(干重)范围内,平均值为0.0051ng/kg,同系物PCB81的检出率最高为90%,而同系物PCB189未被检出。计算的毒性当量(TEQ)值显示,对毒性当量贡献最大的是同系物PCB126,其TEQ值高达117.100pg/g(干重)。由平均残留百分含量较大的同系物结构分析可知,济南市区主要路段道路尘中非邻位氯取代的剧毒类二噁英类PCBs含量相对较大。

Research on the Residual State of DL-PCBs in Road Dust in Jinan

By collecting the main road dust samples in Jinan city,the pollutant residues of 12 types of Dioxin-Like Polychlorinated Biphenyls（DL-PCBs） with higher toxicity were quantitatively analyzed using the method of gas chromatography with electron capture detection（GC-ECD）.The residual concentration,pollution levels and homologues composition of DL-PCBs were investigated in detail.The detection and analysis results indicated that the others 11 DL-PCBs were detected except PCB169 absent in all samples.The total concentration of DL-PCBs was in the range of 0.20～22.84 ng/g（dry weight） and the average value was 0.0051 ng/kg.The content of PCB81 was the most（90%）.The toxic equivalent values（TEQ） showed that the PCB126 had the highest TEQ value,which is 117.100 pg/g（dry weigh）.The average residual percentage analysis of homologues showed that the percent of non-ortho chlorine substituted DL-PCBs were relatively large.