天津滨海新区大气中多氯联苯的季节分布与气粒分配

2013年4月~2014年1月在天津滨海新区泰达学院分季节采集23对大气样品(气相+颗粒相).分析了样品中84种多氯联苯(PCBs)异构体,结果表明,总浓度为71.08~567.36pg/m3(均值307.18pg/m3);春、夏、秋、冬四个季节的PCBs浓度分别为275.19,372.55,259.96,281.81pg/m3,季节规律不明显,冬季浓度偏高,可能是由工业源排放的PCBs和冬季较高的大气颗粒物浓度造成;气相多氯联苯占总浓度的77.47%,且季节差异明显,夏季(92.44%)>秋季(85.16%)>春季(80.61%)>冬季(42.70%);Clausius-Clapeyron (C.C)方程斜率为-5302,表明气相PCBs对温度依赖程度很大,其受到了当地工业源的影响;log KP与log PL0和log KOA的斜率分别为-0.43和0.46,偏离了气粒分配平衡时对应的斜率-1和+1,表明滨海新区大气中多氯联苯受到了当地污染源排放的强烈影响,所以没有达到平衡状态.

Seasonal variation and gas/particle partitioning of atmospheric PCBs from Binhai New District,Tianjin

The 23 paired samples (gas+particle) were collected from Binhai New District (BHND) during April 2013 to January 2014. The 84 PCB congeners were analyzed for each sample and the results were shown as following, the total PCBs concentrations ranged from 71.08 to 567.26 pg/m3 with the mean value as 307.18 pg/m3; The mean values for spring, summer, autumn and winter were 275.19, 372.55, 259.96, 281.81 pg/m3, the weak seasonal distribution trends and relatively higher PCBs levels in winter possibly resulted from the PCBs emission from the local industrial sources and higher particle levels for winter compared with the other three seasons; The gas PCBs accounted for 77.47% of the total PCBs and showed a strong seasonal trends as summer>autumn>spring>winter; The slope of regressed C.C plot was -5302, indicated the gas PCBs were mainly originated from local sources. The slopes for regressed log KP-log PL0 and log PL0-log KOA plots were -0.43 and 0.46, deviated from the –1 and +1 for the equilibrium status of gas/particle partitioning, indicated the strong influence of local industrial sources.