中文摘要：

当前,中国大气中PM2.5污染形势严峻。2013年,在全国纳入监测范围的74座城市中,接近92%的城市的PM2.5年均浓度未达到国家标准,其中,京津冀、长三角和珠三角等重点区域PM2.5污染尤为严重。PM2.5中含有的多种有毒有害物质可直接危害公众身体健康。已有的研究结果显示,PM2.5污染会直接影响人体的呼吸系统、心血管系统,与肺癌的发生率和死亡率密切相关,但需从PM2.5毒理学及暴露-反应关系等影响机制方面做深入研究。中国对大气中PM2.5污染的治理任重道远,强化PM2.5的健康风险研究,科学评价PM2.5污染对中国不同人群疾病发生的负担率等应是认真思考的问题。

英文摘要：

The situation of PM2.5 pollution in China is serious at present. Among 74 cities starting PM2.5 monitoring in 2013, about 92% cities have PM2.5 concentrations exceeding the state standard limit value. The most polluted areas in China are the BeijingTianjin-Hebei region, Yangtze River Delta region and the Pearl River Delta region. Some poisonous species contained in PM2.5 may have a direct influence on human health. Some research results indicate that diseases such as respiratory system and cardiovascular system are evidently affected by PM2.5 pollution. Moreover, PM25 concentration and chemical composition are directly related to lung cancer. Therefore, some key problems, like PM2.5 toxicology, exposure-response relationship and so on, should be further studied, and the health risk assessment on PM2.5 pollution must be strengthened as well.