Environmental Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand.
Environmental Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand; Environmental Chemistry Research Laboratory, Department of Chemistry, Faculty of Science, Chiang Mai, 50200, Thailand.
Environ Pollut. 2022 Jan 15;293:118488. doi: 10.1016/j.envpol.2021.118488. Epub 2021 Nov 15.
Size-fractionated particulate matters (SPMs) in a range of 9.0 to 0.43 μm, classified based on aerodynamic diameter (d) as fine PMs (0.43 μm ≤ d < 2.1 μm) and coarse PMs (2.1 μm ≤ d < 9.0 μm) were collected by cascade impactors (7 fractions) during smoke haze (SH) and non-smoke haze (NSH) seasons in urban and rural areas of Chiang Mai, Thailand. Their polycyclic aromatic hydrocarbons (PAHs) compositions were determined for respiratory health risk assessment. During SH episode, concentrations of SPMs and PAHs in the rural area were approximately two times higher than in the urban area and about 62-68% of the SPMs were fine particles. Conversely, during NSH season the concentrations in the urban area were higher due to traffic emission. The finest particle sizes (0.65-0.43 μm) contained the highest PAHs concentrations among the other PM sizes. Benzo[b]fluoranthene was a main PAH component found during SH season suggesting biomass burning is a major pollutant source. High molecular weight (5-6 rings) PAHs with high carcinogenicity were likely to concentrate in fine particles. Distribution patterns of SPMs and PAHs during SH season were bimodal with the highest peak at a fine size range (0.65-0.43 μm) and a small peak at a coarse size range (5.8-4.7 μm). Respiratory health risk was estimated based on toxicity equivalent concentrations of PAHs bound-SPMs and inhalation cancer risk (ICR). Relatively high ICR values (1.14 × 10 (rural) and 6.80 × 10 (urban)) were found during SH season in both areas, in which fine particles played an important role. It revealed that high concentration of fine particles in ambient air is related to high respiratory health risk due to high content of carcinogenic substances.
在泰国清迈市区和农村地区，烟雾霾（SH）和非烟雾霾（NSH）季节分别使用级联冲击器（7 级）收集了范围在 9.0 至 0.43μm 的粒径分级颗粒物（SPMs），这些颗粒物根据空气动力学直径（d）分为细颗粒物（0.43μm≤d＜2.1μm）和粗颗粒物（2.1μm≤d＜9.0μm）。为了进行呼吸健康风险评估，测定了它们的多环芳烃（PAHs）组成。在 SH 期间，农村地区 SPMs 和 PAHs 的浓度大约是市区的两倍，大约有 62-68%的 SPMs 是细颗粒物。相反，在 NSH 季节，由于交通排放，市区的浓度较高。在其他 PM 粒径中，最细的粒径（0.65-0.43μm）的 PAHs 浓度最高。在 SH 季节，苯并[b]荧蒽是主要的 PAH 成分，表明生物质燃烧是主要的污染源。具有高致癌性的高分子量（5-6 环）PAHs 可能集中在细颗粒物中。SH 季节 SPMs 和 PAHs 的分布模式呈双峰形，最高峰值出现在细粒径范围（0.65-0.43μm），小峰值出现在粗粒径范围（5.8-4.7μm）。基于结合 SPMs 的 PAHs 的毒性等效浓度和吸入致癌风险（ICR），对呼吸健康风险进行了估计。在这两个地区的 SH 季节，相对较高的 ICR 值（农村地区为 1.14×10，市区为 6.80×10）被发现，在这两个地区，细颗粒物都起着重要的作用。这表明，由于致癌物质含量高，环境空气中细颗粒物浓度高与呼吸健康风险高有关。
