中文摘要：

目的探讨2008北京奥运相关大气污染控制措施对大气细颗粒物（PM2．5）金属组分及其细胞毒性的影响。方法于2008年采集奥运前与奥运期间PM2．5，以电感耦合等离子体质谱仪和发射光谱仪测定PM2．5中金属元素含量。以不同浓度的两种PM2．5处理人肺腺癌A549细胞24h，观察PM2．5对细胞膜通透性、线粒体琥珀酸脱氢酶（SDH）活力及溶酶体酸性磷酸酶（ACP）漏出的影响。结果奥运期间PM2．5元素含量大多低于奥运前PM2．5。与对照组相比，奥运前与奥运期间PM2．5在5、25和125μg／ml染毒组中的线粒体SDH活力下降，溶酶体ACP漏出增加（P〈0．05）；奥运前与奥运期间PM2．5在25和125μ／ml染毒组中的细胞膜通透性增加（P〈0．05）。与奥运前相比，奥运期间PM2．5在25和125μg／ml组中对细胞膜通透性的影响较小（P〈0．05）。结论北京奥运相关大气污染控制措施降低了PM2．5中的金属组分含量；奥运前与奥运期间PM2．5均可对A549细胞产生明显的毒性作用；奥运期间PM2．5具有更小的膜毒性，可能与金属组分的降低有关。

英文摘要：

Objective To study the influece of the pollution control measures for the 2008 Beijing Olympic Games on the metal components and the cytotoxicity of fine particulate matter （PM2.5）. Methods PM2.5 was collected before and during Beijing Olympic Games in 2008. The metal elements of PM2.5 were analyzed. The A549 cell was exposed to two kinds of PM2.5 for 24 h at different concentrations. After 24 h of exposure, the cell membrane permeability, the activity of mitochondrial succinate dehydrogenase （SDH） and the leakage of acid phosphatase （ACP） were detected. Results The contents of metal elements of PM2.5 collected during Beijing Olympic Games were lower than those of which collected before Beijing Olympic Games. Above 5 p,g/ml, both kinds of PM2.5 could significantly induce the suppression of SDH activity and the increase in ACP leakage, while the increase in cell membrane permeability was observed at the higher concentration. Compared with PM2.5 collected before Beijing Olympic Games, the impact of PM2.5 collected during Beijing Olympic Games on cell membrane induced significantly decrease in 25 and 125 p.g/ml groups. Conclusion Two kinds of PM2.5 show significant cytotoxicity on A549 cell. The reduction of cell membrane toxicity of PM2.5 collected during Beijing Olympic games may be associated with the reduction of the metal components resulted from the air pollution control measures for the 2008 Beijing Olympic Games.