深圳大运会期间大气中多环芳烃的特征及消减情况研究

深圳大运会期间,利用大流量主动采样器对深圳市5个点位进行大气样品采集,检测其气相及颗粒相中总的多环芳烃(PAHs)浓度以及与2010年夏季的监测数据进行比较,研究PAHs通过各种空气质量保障措施实施后的消减情况.结果表明,大运期间5个点位∑PAHs变化范围为15.80~62.09ng/m3,平均值30.77ng/m3,与2010年夏季相比,PAHs平均消减28%;大运期间PAHs单体中均以3~4环为主,平均占总浓度的88%;通过特征分子比值法推断大运期间机动车尾气排放是PAHs的主要来源,但是柴油车尾气排放和燃煤电厂废气排放的贡献比率增加;大运期间∑BaPeq比2010年夏季降低36%,BaP浓度以及∑BaPeq浓度都低于我国环境空气中对BaP的限值标准;呼吸致癌风险评价表明,大运期间为每百万人致癌3.8例,2010年夏季为每百万人致癌7.3例,致癌风险下降48%.

Pollutant characterization and reduction of polycyclic aromatic hydrocarbons (PAHs) in atmosphere during Shenzhen Universiade

Air samples of five sampling sites in Shenzhen were collected by the active Hi-Vol air sampler during 2011 Shenzhen Universiade. The PAHs in both air phase and particulates phase were analyzed, and the statistically reductions for all PAHs during the Shenzhen Universiade by all kinds of air quality protection measures relative to the summer of 2010 were studied. The concentrations of ∑PAHs in Shenzhen Universiade ranged from 15.80 to 62.09ng/m3(average: 30.77 ng/m3), a reduction of 28% compared with the summer of 2010.The 3-ring and 4-ring PAHs are the main monomers, which accounted for 88%. It is indicated that vehicle exhaust was the major PAHs source,but the PAHs contribution rate of Diesel car and coal combustion increased during Shenzhen Universiade by the diagnostic ratio method,.∑BaPeq was reduced by 36% compared with the summer of 2010, the concentration of BaP and ∑BaPeq in five sites were below our country’s limited standard. The study of the inhalation cancer risk showed that the PAHs inhalation exposure lead to 7.3 cancer cases per million people in the summer of 2010, whereas the cases decreased to 3.8 in Shenzhen Universiade, a reduction of 48%.