利用树皮作为生物指示物监测大气中的二噁英

Using tree bark as biomonitor to monitor atmospheric dioxins in an E-waste dismantlying area

目的相比于空气样品,树皮具有易采集,易运输和对POPs有很好吸附等特点,利用树皮作为生物指示物监测空气中半挥发性有机化合物。方法该研究选择我国某电子垃圾典型拆解地区作为试验点,采用高通量同位素稀释-高分辨气质联用法分析树皮样品（n=23）中的二噁英。结果结果显示树皮中二噁英的总浓度为（107.8±12.4）×10^3pg g^-1脂肪重,毒性当量为（1.3±0.1）×10^3pgTEQg-1脂肪重。通过和其它地区的研究对比发现,该地区树皮样品中二噁英浓度是目前为止所有同类样品中浓度最高的之一,该结果表明试验点地区受到严重的二噁英污染。结论通过对树皮中二噁英的指纹特征进行研究,说明该地区二噁英污染主要来源于电子垃圾的无序焚烧。

Objective Tree bark had been used as biomonitor to monitor atmospheric semi-volatile organic compounds（SVOCs）.Methods To investigate the environmental level and profile of polychlorinated dibenzo-p-dioxins and dibenzofurans（PCDD/Fs）,tree bark samples（n=23）were collected from an e-waste recycling area in China.Results The average concentration of PCDD/Fs determined by isotope dilution-high resolution gas chromatography（HRGC）coupled with high resolution mass spectrometer（HRMS）was（107.8±12.4）×10^3 pg g^-1 lipid weight.PCDD/F-toxic equivalent（TEQ,WHO-1998）was（1.3±0.1）×10^3 pg TEQ g^-1 lipid weight.The profile of PCDD/Fs in the tree bark was also discussed.Tetra-CDFs was the main homologue and accounted for 30.4% of total PCDD/Fs;As for TEQs,2,3,4,7,8-PeCDF were the main contributors and accounted for 33.4% of the total PCDD/F-TEQs.Comparing with the worldwide tree bark samples,high accumulation of PCDD/Fs in the sample indicated heavy contamination of these pollutants in the studied area.Conclusions The homologue and congener profile of PCDD/Fs suggested that these pollutants were originated from the crude E-waste recycling activity,such as open-burning of E-waste.