上海市大气颗粒物生物毒性及二噁英呼吸暴露风险评价

Biotoxicity effects and respiratory risk assessment of PCDD/Fs exposured to atmospheric particulates in Shanghai

使用Vibrio fischeri发光细菌法,评价了工业区和居民区大气颗粒物悬浮液的细菌毒性,并对颗粒物暴露后的老鼠毒性效应进行了分析和讨论;应用HRGC-HRMS研究了工业区大气中二噁英浓度水平及组分特征,并在此基础上开展了二噁英呼吸暴露风险评价.结果显示:工业区大气颗粒物的细菌毒性要明显高于居民区,表明急性毒性结果与局地污染排放密切相关;不同粒径分布的大气颗粒物细菌毒性结果产生显著差异,证明毒性成分主要吸附在较细粒径的颗粒物上.强有力的证据表明,颗粒物暴露后的肺组织病理损伤与氧化性自由基过量产生有关,因此与自由基相关的毒理机制可作为下一步深入研究的路径.4个采样点主动采样、被动采样和大气沉降样品二噁英浓度范围分别为0.034~1.29pg/m^3、0.031~0.103pg/m^3和0.226~4.67pg/(m^2·d),平均值分别为0.366pg/m^3、0.063pg/m^3和1.82pg/(m^2·d);优势组分分别为2,3,4,7,8-Pe CDF、2,3,4,6,7,8-Hx CDF、1,2,3,6,7,8-Hx CDF和1,2,3,4,7,8-Hx CDF,2,3,4,7,8-Pe CDF、1,2,3,7,8-Pe CDD、2,3,7,8-TCDD和2,3,7,8-TCDF,2,3,4,7,8-Pe CDF、1,2,3,7,8-Pe CDD、2,3,4,6,7,8-Hx CDF和1,2,3,6,7,8-Hx CDF.成人和儿童呼吸暴露量最大值分别为9.74×10^(-2)pg/(kg·d)和1.28×10^(-1)pg/(kg·d),均低于0.4pg/(kg·d)(呼吸进入人体的每日允许摄入量),表明暴露风险处于可接受水平.

Bacterial toxicity of atmospheric particulate suspensions in residential and industrial areas was evaluated with Microtox test（Vibrio fischeri）,and the toxicity effects of rats after particulate exposure were also analyzed and discussed.HRGC-HRMS was applied to study concentration level and composition characteristic of PCDD/Fs,in addition,dioxin respiratory exposure risk assessment was conducted based on the data analysis.Results showed that the acute toxicity of atmospheric particulate in industrial site was higher than those in residential site,which indicated that acute toxicity was closely related to local pollution.The bacterial toxicity results of airborne particles with different particle sizes were significantly different,which suggested that toxicant was mainly adsorbed on finer particles.Exposure experiment studies provided overwhelming evidence that pathological damage of lungs after particulate exposure was correlative with overproduction of oxidative free radical,so toxicological mechanism associated with free radicals could be used as a pathway for further in-depth study.Concentration of PCDD/Fs ranged from 0.034～1.29pg/m^3 in active sampling,from0.031～0.103pg/m^3 in passive sampling,and from 0.226～4.67pg/（m^2·d）in atmospheric deposition sampling respectively,with a mean concentration of 0.366pg/m^3,0.063pg/m^3 and 1.82pg/（m^2·d）respectively.Dominant composition characteristics of PCDD/Fs were 2,3,4,7,8-Pe CDF,2,3,4,6,7,8-Hx CDF,1,2,3,6,7,8-Hx CDF,1,2,3,4,7,8-Hx CDF for active sampling,2,3,4,7,8-Pe CDF,1,2,3,7,8-Pe CDD,2,3,7,8-TCDD,2,3,7,8-TCDF for passive sampling,and 2,3,4,7,8-Pe CDF,1,2,3,7,8-Pe CDD,2,3,7,8-TCDD,2,3,7,8-TCDF for atmospheric deposition sampling respectively.Maximum respiratory exposures of adult[9.74×10^（-2）pg/（kg·d）]and children[1.28×10^（-1）pg/（kg·d）]were lower than 0.4pg/（kg·d）^（-1）（maximum allowed daily intake）,which indicated an acceptable level of inhalation exposure risk.