电子垃圾拆解对台州氯代/溴代二噁英浓度和组成的影响

电子垃圾拆解会导致有毒有害污染物向大气的排放,造成环境污染的产生。为了解电子垃圾拆解及废旧金属再生活动对拆解地及邻近地区空气质量的影响,对台州峰江金属再生园区附近及对照区路桥市区大气中(气态和颗粒态)氯代二噁英(PCDD/Fs)、溴代二噁英(PBDD/Fs)的含量、同系物组成及气/固分配规律进行了研究,通过相关性分析探讨了PCDD/Fs和PBDD/Fs的可能来源。结果显示,金属再生园区冬季采样期间17种2,3,7,8-PCDD/Fs和8种2,3,7,8-PBDD/Fs的平均浓度分别为212.2 pg·m-3和17.6 pg·m-3,夏季采样期间的平均浓度分别为84.5 pg·m-3和5.4 pg·m-3,均显著高于对照点。夏季采样期间对照点处于再生园区的下风向,其二噁英浓度高于冬季,说明其受到了金属再生园区的明显影响。基于相关性分析的结果,塑料焚烧是金属再生活动中氯代和溴代二噁英的主要来源。初步的暴露风险评价表明,金属再生园区附近居民每日摄入的二噁英含量远远超过世界卫生组织规定的人体每日耐受量(1~4 pg W-TEQ·kg-1·d-1)。上述研究结果为规范电子垃圾拆解活动提供了基础数据。

Impact of E-Waste Dismantling Activities on the Levels and Compositions of PCDD/Fs and PBDD/Fs in the Atmosphere of Taizhou

Toxic pollutants will be introduced into the atmosphere and cause environmental pollution during the e-waste dismantling processes. To get a better understanding of the impact of e-waste dismantling and metal recycling activities on the air quality of the local and surrounding areas of the e-waste dismantling area, gaseous and particulate samples were collected in the atmosphere around the Fengjiang metal-recycling industrial park and in the urban area in Taizhou of China to investigate the concentrations, homologous compositions and gas/particle partitioning of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and polybrominated dibenzo-p-dioxins/dibenzofurans (PBDD/Fs). Potential sources of the atmospheric dioxins were investigated through correlation analysis. The average concentrations of 2,3,7,8-PCDD/Fs and 2,3,7,8-PBDD/Fs near the industrial park during the winter sampling period were 212.2 pg?m-3 and 17.6 pg?m-3, and 84.5 pg?m-3 and 5.4 pg?m-3 during the summer period, respectively, which were significantly higher than those at the control site in the urban area. Being in the downwind direction of the e-waste dismantling area during the summer sampling period, the urban area was influenced by the pollutants from the dismantling activities and thus showed higher dioxin concentrations during the summer period than that during the winter sampling period. Correlation analysis showed that the concentrations of dioxins were significantly correlated with those of PBDEs, Cl- and quaterphenyl, indicating that burning of plastic materials was the main source of airborne dioxins near the e-waste dismantling area. Preliminary inhalation risk assessment showed that the total dioxins intake doses of the residents near the e-waste dismantling area at Fengjiang town of Taizhou far exceeded the tolerable daily intake limit (1~4 pg W-TEQ?kg^-1?d-1) suggested by WHO. The results of this study provided basic data for the regulation of e-waste dismantling and metal-recycling activities.