京津冀地区有害重金属大气排放污染时空特征、源解析及暴露风险研究

Recently, sever haze pollution frequently happened in the Beijing-Tianjin-Hebei regions of China have been one of the hottest topics in the atmospheric environment field throughout the world. Therein, the temporal and spatial distribution characteristics, source appointment of toxic heavy metals which were mainly adsorbed on the fine particles have received highlighted concerns owing to their adverse effects on human health and eco-environment. In this program, several toxic trace elements including Pb, As, Cd and Sb were selected as targeted elements in the Beijing-Tianjin-Hebei regions, the atmospheric emission characteristics and emission factors of these elements were determined according to the field-test measurements for selected typical sources, and the regional emission inventory of these elements was developed by combing the relevant activity levels; further the inventory was gridded into 0.1º ×0.1º resolution with ArcGIS system and was used for input data to conduct atmospheric concentration simulation by using WRF-CHEM models. On the same time, by applying multi-level particle sampling instruments, ambient aerosol collection and analysis for TSP/PM10/PM2.5/PM1.0 will be carried out in different seasons and typical heavy pollution periods in Beijing and several surrounding cities such as Baoding, Shijiazhuang, and Langfang cities, so as to obtain the temporal and spatial distribution characteristics of the targeted elements and their accumulation features on different diameter-levels particles, then source appointment of Pb and As will be explored by using receptor models such as CMB. In addition, the preliminary assessment of exposure risks on atmospheric toxic elements such as Pb for different inhabitants in the regions will be attempted to conduct based on the results of typical source measurements and regional ambient exposure. Consequently, a much better understanding of these targeted toxic elements on their temporal and spatial characteristics, source appointment as well as potential exposure risks on public health, can supply very useful information on implementing regional complex air pollution control and comprehensive prevention of heavy metals pollution in China.

京津冀地区长时间大范围严重灰霾污染是全球关注的大气环境热点问题，主要以细颗粒形式存在的有害重金属大气排放污染、源解析及健康影响尤为值得重视。课题针对铅、砷、镉等有害元素,通过典型源现场烟气排放测试分析等构建本地化排放因子，结合地区活动水平建立京津冀地区0.1 ×0.1 网格化大气排放清单，输入WRF-CHEM模式开展区域大气浓度模拟,识别重污染地区和重点排放源；同时在北京及周边保定、石家庄、廊坊等城市选择不同季节和重污染时段开展大气TSP/PM10/PM2.5/PM1.0颗粒物采样分析，获取有害元素污染时空分布与输送特征及其在不同粒径颗粒的富集规律,并耦合CMB等受体模型进行源解析；进而初步开展该地区不同人群大气铅、砷、镉暴露风险评价。从而系统深入探究京津冀地区铅、砷、镉等有害重金属大气排放污染时空分布及区域传输特征、来源解析及健康风险，为区域复合大气污染控制和重金属污染防治提供科学依据。

近年来，以颗粒物形式存在的有害重金属元素大气排放及其对人类健康和生态环境的危害受到广泛关注。本研究基于经济发展和技术扩散理论，首次建立了典型人为源有害重金属大气排放因子动态估算模型，综合使用排放因子法和ArcGIS地理信息系统工具，系统构建了多尺度区域长时间跨度、多种有害重金属高时空分辨率的典型人为源12种有害重金属(Hg, As, Se, Pb, Cd, Cr, Ni, Sb, Mn, Co, Cu and Zn)大气排放清单。结合大型点源（燃煤电厂、工业锅炉、有色冶炼、水泥、钢铁等）经纬度信息和GDP、人口分布等面源污染分配因子，利用ArcGIS地理信息软件对排放清单进行了精细化网格处理，获取了具有高时空分辨率9 km×9 km的京津冀地区有害重金属元素的时空分布特征，并采用蒙特卡罗模拟法对排放清单结果的不确定性进行了量化分析；针对京津冀地区，以9 km×9 km京津冀地区有害重金属元素大气排放清单为输入条件，利用WRF-CMAQ模式，开展了有害重金属（如As、Pb、Cd、Cr、Ni、Cu等）大气质量浓度数值模拟分析探索研究；选取京津冀及周边典型城市（北京、天津、保定、廊坊等）开展气颗粒物采样分析，深入探究了大气颗粒物及其重金属组分的理化特征及时空变化规律，结合后向轨迹分析、统计方法分析及PMF模型等受体源解析方法和手段，揭示了该地区大气颗粒物及典型有害重金属的来源及迁移转化规律，同时，利用EPA模型对重金属的人群暴露风险进行了系统评价。本项目共培养7名博士生（其中已毕业3人）、11名硕士生（已毕业6人）、中青学术带头人2名。研究团队成员先后参加国际会议和国内会议20余次。2014年至今在国内外重要学术期刊及国际国内会议共发表论文26篇和会议报告20余次。SCI收录期刊论文22篇，其中在ES&T、ACP、Atmos. Environ.、STOTEN、 Environ. Pollut.等TOP杂志发表SCI TOP论文16篇，一区TOP4篇，影响因子合计80，引用350余次。