天津黑碳气溶胶潜在来源分析与健康风险评估

采用2010~2013年BC连续在线观测资料，分析天津地区BC的季节分布、潜在来源及其健康效应.结果表明，2010~2013年BC气溶胶浓度平均值为（4.49±3.26）μg/m³，秋季浓度最高，为6.31μg/m³，冬季和夏季次之，春季最低，为2.59μg/m³.各季节BC浓度的日变化特征类似，均呈早晚双峰分布，早间峰值高于晚间，且夜间高于日间.混合层高度和近地层风从垂直和水平两方面影响BC的时空分布，各季节作用强度并不相同.浓度权重轨迹分析表明天津高浓度BC的主要贡献区域为河北、山东、河南等华北平原地区.此外，秋季内蒙古中部和山西北部等西北区域也会影响天津.天津城区各季节成人和儿童的致癌风险（CR）均高于EPA给定的可接受风险水平（10^-6），非致癌风险水平较低，秋季因高浓度BC引发的呼吸系统死亡率相对风险为1.118，需要引起高度关注.

Potential source analysis and health risk assessment of black carbon aerosol in Tianjin City

Black carbon (BC) produced by incomplete combustion of fossil fuels and biofuels has an important impact on human health and climate change. Based on the continuous online observation data of Tianjin from 2010 to 2013, the seasonal distribution, potential sources and health effects of BC in the atmosphere of Tianjin were analyzed. The average BC aerosol concentration was (4.49±3.26)μg/m³, which was the highest in autumn, the second in winter and summer, and the lowest in spring. The diurnal variation characteristics of BC concentration in different seasons were similar, showing a bimodal distribution in the morning and evening. The peak value in the morning was higher than in the evening. The concentration of BC in night was higher than that in day in each season. Mixed layer thickness (MLT) and near-surface wind affected the spatial and temporal distribution of BC under horizontal and vertical directions. Concentration weight trajectory (CWT) analysis showed that Hebei, Shandong and Henan were the main potential areas affecting BC in Tianjin. In addition, northwest regions such as Inner Mongolia and northern Shanxi affected Tianjin in autumn. The lifetime cancer risk (CR) of adults and children in Tianjin was higher than USAEPA given acceptable risk level (10^-6), but the Hazard Quotien(HQ) was acceptable. Since the relative risk (RR) of respiratory mortality caused by high concentration of BC in autumn was 1.118, we need to pay close attention to the health risk of BC.