State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Faculty of Environmental Engineering, The University of Kitakyushu, 1-1 Hibikino, Wakamatsu, Kitakyushu, Fukuoka 808-0135, Japan.
Ecotoxicol Environ Saf. 2021 Mar 15;211:111937. doi: 10.1016/j.ecoenv.2021.111937. Epub 2021 Jan 19.
In order to investigate the pollution characteristics of size-segregated particles and metal elements (MEs) after the Chinese Air Pollution Prevention Action Plan was released in 2013, an intensive field campaign was conducted in the suburban area of Chaoyang District, Beijing in winter 2016. The size distributions of particle mass concentrations were bimodal, with the first peak in the fine fraction (0.4-2.1 µm) and the second peak in the coarse fraction (3.3-5.8 µm). Moreover, the proportion of fine particles increased and the proportion of coarse particles decreased as the pollution level was more elevated. It was found that the composition of coarse particles is as important as that of fine particles when pollution of aerosol metals in the atmosphere in 2016 were compared to 2013. In addition, according to the size distribution characteristics, 23 MEs were divided into three groups: (a) Fe, Co, Sr, Al, Ti, Ba, and U, which concentrated in coarse mode; (b) Zn, As, Cd, Tl, and Pb, which concentrated in fine mode; and (c) Na, K, Be, V, Cr, Mn, Ni, Cu, Mo, Ag, and Sn, showing bimodal distribution. Under clean air, slight pollution and moderate pollution conditions, most elements maintained their original size distributions, while under severe pollution, the unimodal distributions of most MEs became bimodal distributions. The factors analysis combined with size distributions indicated that Na, Zn, Mo, Ag, Cd, and Tl, showing the moderate to severe contamination on environment, were significantly influenced by diffuse regional emissions or anthropogenic source emissions (vehicle exhaust emissions and combustion process). The environmental risk assessment revealed that the heavy metal loading in the atmospheric particles collected had a high potential for ecological risk to the environment during sampling period because of the high contribution of Cd, Tl, Zn and Pb.
为了研究 2013 年中国空气污染防治行动计划实施后大气颗粒物中元素（MEs）的污染特征，我们于 2016 年冬季在北京朝阳区郊区进行了一次强化野外活动。颗粒物质量浓度的粒径分布呈双峰形态，第一个峰值在细颗粒（0.4-2.1μm），第二个峰值在粗颗粒（3.3-5.8μm）。此外，随着污染水平的升高，细颗粒的比例增加，粗颗粒的比例减少。结果表明，与 2013 年相比，2016 年大气气溶胶金属污染时，粗颗粒的组成与细颗粒一样重要。此外，根据粒径分布特征，将 23 种 ME 分为三组：（a）Fe、Co、Sr、Al、Ti、Ba 和 U，主要集中在粗模态；（b）Zn、As、Cd、Tl 和 Pb，主要集中在细模态；（c）Na、K、Be、V、Cr、Mn、Ni、Cu、Mo、Ag 和 Sn，呈双峰分布。在清洁空气、轻度污染和中度污染条件下，大多数元素保持其原始粒径分布，而在严重污染条件下，大多数 ME 的单峰分布变为双峰分布。结合粒径分布的因子分析表明，Na、Zn、Mo、Ag、Cd 和 Tl 等元素对环境的中度至重度污染受到区域扩散排放或人为源排放（车辆尾气排放和燃烧过程）的显著影响。环境风险评估表明，由于 Cd、Tl、Zn 和 Pb 的高贡献率，大气颗粒物中重金属负荷在采样期间对环境具有很高的生态风险。
