多溴联苯醚、多氯联苯在典型污染地区的大气-植物交换及来源解析

项目名称： 多溴联苯醚、多氯联苯在典型污染地区的大气-植物交换及来源解析

项目编号： No.40801199

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 化学工业

项目作者： 陈社军

作者单位： 中国科学院广州地球化学研究所

项目金额： 20万元

中文摘要： 对清远电子垃圾处理地区和对照区大气和植物中的HFRs和PCBs进行了研究。主要成果有：1)电子垃圾拆卸是珠三角大气中HFRs污染的重要来源之一，受温度控制的从污染介质中的挥发是大气中低卤代HFRs重要来源，但对于颗粒物HFRs的主要来源和释放机制还不清楚，需要进一步研究。2)植被是该地区HFRs重要的储蓄体，植被和大气之间的HFRs之间的交换受温度影响，并能影响大气中的浓度；拆卸区和对照区植被中HFRs的浓度之间的差距比大气中小得多。研究阐明了HFRs的大气-植物交换机制，自然条件下对早期的模型进行了验证；颗粒物沉降是植物从大气中吸收大多数HFRs的重要途径，第一次阐明了这一分配过程与污染物KOA的非线性关系。3)对电子垃圾拆卸地、城市地区和农村对照区的HFRs的大气沉降进行了调查；并初步探讨了不同HFRs在大气中的迁移；通过PCA-MLR对对照地区大气中的BFRs的来源进行了解析，揭示了珠三角工业和电子垃圾拆卸活动是该地区最主要的HFRs来源。4)目前对PCBs的数据还在分析当中，PCBs的手性特征和HFRs结果的对比等将会对该地区大气和植物中SOCs污染和环境行为有更深的认识。

中文关键词： 多溴联苯醚（PBDEs）；多氯联苯（PCBs）；植物大气交换；电子垃圾

英文摘要： Halogenated flame retardants (HFRs) and polychlorinated biphenyls (PCBs) in the atmosphere and plants at an e-waste site and a reference site in Qingyuan, South China were measured. The major results are: 1) E-waste dismantling activity is one of the most important sources of HFRs in the atmosphere in the Pearl River Delta (PRD). The gaseous concentrations of less halogenated HFRs at e-waste site were strongly controlled by temperature-driven evaporation from contaminated surfaces except for winter, whereas the emission mechanisms of HFRs associated with airborne particles are not clear yet. The physicochemical properties of the atmospheric particles at the e-waste and reference sites were probably different, for which more research is needed. The results also suggests that the primitive e-waste recycling in the developing countries in Asian is a signi?cant source of these chemicals and has important implications for their global transport. 2) Vegetation is an important sink of HFRs in the studied area. The air-plant exchange of HFRs was influenced mainly by temperature, and would affect the concentration of HFRs in the air. The difference in HFR concentrations between the e-waste and reference sites was much smaller in the vegetation than that in the air. This study clarified the air-plant exchange mechanism and verified the previous interpretative framework under nature condition. Particle-bound deposition is an important pathway for plant uptake of HFRs from atmosphere. This study is the first report on the nonlinearity relationships between log plant/air partition coefficient (KPA) and log octanol-air partition coefficients (KOA). 3) Atmospheric deposition of HFRs at e-waste, urban and rural (reference) sites was investigated and atmospheric transport of individual HFRs was discussed. Source apportionment of HFRs in the atmosphere at the reference site was estimated by principal component analyses with multiple linear regression analysis (PCA-MLR). The industrial and e-waste recycling activities in the PRD are two important sources of HFRs in the environment. 4) Data analysis for PCBs in the samples is still in process. This will add further understanding of SOCs in the air and vegetation at these sites and their environmental behavior by comparing the results of PCBs and HFRs and by analyzing the chiral signitures of PCBs.

英文关键词： Polybrominated diphenyl ethers (PBDEs); Polychlorinated biphenyls (PCBs); Air-plant exchange; E-waste