典型电子垃圾拆解区二噁英污染特征、相分配及暴露风险

选取南方某典型电子垃圾拆解区不同作业区为研究对象，重点研究了拆解地大气中二噁英的污染特征、气相-颗粒相分配及呼吸暴露风险。通过对5个采样点（包括1个背景点）的研究发现，电子垃圾拆解作业区颗粒相ΣPCDD/Fs的质量浓度为：20.64-56.14 pg·m^-3，毒性当量为：I-TEQ 0.293-1.490 pg·m^-3；气相ΣPCDD/Fs的质量浓度为：3.861-19.29 pg·m^-3，毒性当量为：I-TEQ 0.384-2.150 pg·m^-3。背景点大气中二噁英浓度相对较低，颗粒相和气相样品中质量浓度值分别为：3.734 pg·m^-3和2.637 pg·m^-3,毒性当量仅为I-TEQ 0.176-0.267 pg·m^-3；要明显低于电子垃圾拆解区。基于污染物气相-颗粒相分配系数与蒸汽压的关系对二噁英的气-固分配行为研究显示，除了拆解混合作业区有较好的分配系数（-0.64）外，其它监测点位二噁英的气-固平衡状态较弱（-0.27--0.03），更多的是以低分子量的单体化合物赋存于气相样品中。对拆解区二噁英呼吸暴露风险研究结果表明，儿童呼吸暴露风险要高于成年人；同时无论是儿童还是成年人，其二噁英的呼吸暴露量均要高于国内外城市报道的二噁英人体呼吸暴露量，说明本次监测的电子垃圾拆解区存在的潜在健康风险不容忽视。

Pollution Characteristics,Gas/Particle Partitioning and Inhalation Risk Assessment of Dioxin in the Typical e-waste Dismantling Region

Different operating sites in the typical electronic waste （E-waste） dismantling region, south China, have been selected to study. A short-term sampling scheme was devised to determine the levels of gas/particle-bound polychlorinated dibenzo-p-dioxins and dibenzofurans （PCDD/Fs） in and to evaluate the impact of PCDD/Fs on the lives of the inhabitants in E-waste dismantling region. Samples were collected from five different operating sites （including one background） of dismantling area, and the results indicated that the particle and gas PCDD/Fs concentrations （toxic equivalent quantity （TEQ）） for dismantling area were 20.64-56.14 pg·m^-3（0.293-1.490 pg I-TEQ·m^-3） and 3.861-19.29 pg·m^-3 （0.384-2.150 pg I-TEQ·m^-3）, respectively, which were higher than the concentration of particle and gas PCDD/Fs（3.734 pg·m^-3 and 2.637 pg·m^-3） for the background, and the TEQ in the latter sampling site only has 0.176-0.267 pg I-TEQ·m^-3. Based on relation of gas/particle partitioning coefficient and sub-cooled liquid vapor pressure pressure for pollutants, the research for behavior of PCDD/Fs in gas/particle partitioning showed that the gas/particle equilibrium state was weak （-0.27--0.03） in the most of monitoring sites, except for mixed operation site （the distribution coefficient was-0.64）, which were more low molecular weight of monomer compounds in gas phase. Results of daily intake of PCDD/Fs by inhaling air suggested that the inhalation exposure of PCDD/Fs by the inhabitants for children is higher than adults. In addition, the results were higher than daily intake of PCDD/Fs in other city, which indicated that the potential health risks of e-waste dismantling region in this research can not be ignored.