关中农村生物质燃烧排放棕碳气溶胶的人体暴露健康效应

Biomass burning is one of the important sources to Brown Carbon (BrC), which is the important species of particulate matters (PM). Guanzhong Plain is one of the major areas in which the air quality is heavily polluted by the high PM concentrations. The biomass is used as the main heating fuel in most rural households in this area. Due to the fine and ultrafine particle size distribution characteristic of BrC, and complexity and toxicity in its chemical compositions, the toxicological effects for human from BrC emitted from the biomass burning, as well as the related epidemiologic study need to be studied urgently. In this proposal, personal exposure sampling and epidemiological survey will be carried out for housewives who stayed in the biomass combustion environment for long time in Guanzhong rural area. An improved seven-wavelength DRI2015 thermal/optical carbon analyzer will be applied for rapid and accurate analysis the concentrations of low-content and different particle sizes personal exposure BrC. This work aims to estimate the influences of varied burning ways and biomass fuels to the personal exposure BrC and the quantitative correlations with the reactive oxygen species (ROS) and epidemiological indexes, to investigate the effects of different particle sizes BrC on respiratory and cardiovascular systems, and try to find out the toxicology mechanism of BrC to human. This research will enhance our understanding on the BrC potential environmental and health impacts, provide basic data and scientific advice for the rural residents for individual health protection in Northern China.

生物质燃烧排放是大气颗粒物中重要成分棕碳（BrC）的主要来源之一。关中地区细颗粒物污染是全国最为严重的区域之一，生物质是该地区农村家庭的主要燃料。由于BrC细及超细粒径的富集特点和化学成分的复杂性与毒性，亟需开展生物质燃烧排放主导的BrC引发的健康毒性效应和流行病学研究。本项目拟在关中地区农村使用颗粒物个体暴露采样器对长期生活在生物质燃烧环境中的家庭主妇进行不同粒径颗粒物的采集及流行病学调查，采用先进的七波段DRI2015热/光碳分析仪快速准确地测量低含量多粒径的人体暴露BrC的浓度分布，查明不同固体燃料和燃烧方式对BrC人体暴露的影响及其与造成细胞损伤的活性氧簇（ROS）和流行病学、毒理学指标的定量关联，探讨不同粒径BrC对呼吸和心血管系统的影响，尝试查明BrC健康负效应的毒理学机制。该研究将提高我们对BrC潜在环境影响和致病机制的认识，为我国北方农村居民健康防护提供研究案例和科学建议。

家用固体燃料燃烧仍是汾渭平原地区农村冬季大气污染的主要贡献源。本项目在汾渭平原的典型代表城市（西安、铜川、运城等）农村地区开展了对不同固体燃料使用者的人体暴露大气颗粒物（PM）采集，准确地定量了不同固体燃料燃烧对不同粒径PM中棕碳（BrC）的关键组分（多环芳烃[PAHs]和硝化酚[NPs]等）的人体暴露的影响，得出了大气污染物暴露与人体炎症、氧化应激等健康指标的关联。. 铜川市清洁煤使用者呈现最低的PAHs和NPs暴露浓度，清洁煤替代块煤和生物质后各粒径PM和NPs浓度分别降低了28.6-66.3%和52.2-82.4%，PAHs暴露浓度降低了89.0-93.9%；人体炎症因子（IL-6）和氧化应激因子（8-OHdG）降低了12%-72%，血管内皮生长因子（VEGF）升高了65%。运城市在线污染物数据表明电/无加热组的三种粒径颗粒物（即PM10、PM2.5、PM1）的人体暴露浓度分别比煤组低5.1%、9.1%和12%。西安冬夏两季流行病学调查发现尿液中IL-6、8-OHdG、HR、SBP、DBP在冬季显著高于夏季，固体燃料使用者尿液中的IL-6水平明显高于非固体燃料使用者；在铜川市发现唾液中的IL-6与燃料PM2.5、OC、EC的排放因子（EFs）的显著正相关性以及唾液中8-OHdG与PM2.5、OC的EFs的显著正相关性；在运城市得出与尿液中8-OHdG、IL-8与PMs、NO2暴露剂量的正相关性。. 本项目定量研究了固体燃料排放的大气PM中特定BrC组分的暴露水平与粒径相关的潜在健康危害，评估了不同污染物暴露对流行病学指标的影响，为进一步认识到我国家用固体燃料排放污染物的致病和损伤机理做出了贡献，为政府制定北方农村家庭的能源使用策略提供科学性建议，促进我国北方农村能源转型。