Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan.
Int J Environ Res Public Health. 2020 Nov 6;17(21):8224. doi: 10.3390/ijerph17218224.
Daily PM (particulate matter with aerodynamic diameter ≤2.5 μm) samples were simultaneously collected at two background sites (Wajima Air Monitoring Station (WAMS) and Fukue-Jima Atmosphere and Aerosol Monitoring Station (FAMS)) in Japan in the East Asian winter and summer monsoon periods of 2017 and 2019, to compare the characteristics of air pollutants among different regions and to determine the possible variation during the long-range transport process. Polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs (NPAHs), and water-soluble inorganic ions (WSIIs) were analyzed. Despite the PM concentrations at FAMS (8.90-78.5 µg/m) being higher than those at WAMS (2.33-21.2 µg/m) in the winter monsoon period, the average concentrations of ∑PAHs, ∑NPAHs, and ∑WSIIs were similar between the two sites. Diagnostic ratios indicated PAHs mainly originated from traffic emissions and mostly aged, whereas NPAHs were mostly secondarily formed during long-range transport. WSIIs at WAMS were mainly formed via the combustion process and secondary reactions, whereas those at FAMS mainly originated from sea salt and dust. Backward trajectories revealed the air masses could not only come from Asian continental coastal regions but also distant landlocked areas in the winter monsoon period, whereas most came from the ocean in the summer monsoon period. These findings can provide basic data for the establishment of prediction models of transboundary air pollutants in East Asia.
在 2017 年和 2019 年东亚冬、夏季季风期间，在日本的两个背景站点（Wajima 空气监测站（WAMS）和福江大气和气溶胶监测站（FAMS））同时采集了每日 PM（空气动力学直径≤2.5μm 的颗粒物）样品，以比较不同地区空气污染物的特征，并确定在长程传输过程中可能发生的变化。分析了多环芳烃（PAHs）、硝基多环芳烃（NPAHs）和水溶性无机离子（WSIIs）。尽管冬季季风期间 FAMS 的 PM 浓度（8.90-78.5μg/m）高于 WAMS 的浓度（2.33-21.2μg/m），但两个站点的∑PAHs、∑NPAHs 和∑WSIIs 的平均浓度相似。诊断比表明 PAHs 主要来源于交通排放，且大部分已经老化，而 NPAHs 主要在长程传输过程中形成。WAMS 上的 WSIIs 主要通过燃烧过程和二次反应形成，而 FAMS 上的 WSIIs 主要来自海盐和灰尘。后向轨迹表明，在冬季季风期间，空气团不仅可以来自亚洲大陆沿海地区，还可以来自内陆地区，而在夏季季风期间，空气团主要来自海洋。这些发现可以为东亚跨境空气污染物预测模型的建立提供基础数据。
