Institute of Mass Spectrometry and Atmospheric Environment, Guangdong Provincial Engineering Research Center for On-line Source Apportionment System of Air Pollution, Jinan University, Guangzhou, 510632, PR China; State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou, 510632, PR China.
State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China.
Environ Res. 2022 Nov;214(Pt 4):114075. doi: 10.1016/j.envres.2022.114075. Epub 2022 Aug 10.
Although recent laboratory simulations have demonstrated that organic matter prevents the degradation of polycyclic aromatic hydrocarbons (PAHs), their role in the long-range transport of PAHs in the real atmosphere remains poorly understood. In this study, we measured the chemical composition and mixing state of PAHs-containing individual particles in aerosols from three sources, one urban area and one remote area. PAHs-containing particles were classified into five types: organic carbon (OC), potassium mixed with organic carbon (KOC), potassium mixed with sodium (KNa), Krich and PAH-rich. The PAH-rich and KOC particles were the main types of particles produced by vehicle exhaust/coal burning and biomass burning, respectively, accounting for >50% of the PAHs-containing particles. It was found that organic matter enhancement of PAHs-containing particles occurs in the ambient atmosphere, with organic-rich (OC and KOC) particles accounting for >90%. Further analysis revealed that the increase in the fractions of PAHs was related to the mixing state with organic compounds due to the protection of organics against PAHs and/or the aging of PAHs-containing particles. The results of this study improve our understanding of the chemical composition and mixing state of PAHs particles in atmospheric aerosols from emission sources and urban and remote areas, and provide field observation evidence to support the promotion of the study of long-range transport of PAHs by organics.
虽然最近的实验室模拟表明，有机物可以防止多环芳烃（PAHs）的降解，但它们在大气中长距离传输 PAHs 的作用仍不清楚。在这项研究中，我们测量了来自三个来源（一个城市地区和一个偏远地区）的气溶胶中含 PAHs 的单个颗粒的化学组成和混合状态。含 PAHs 的颗粒被分为五种类型：有机碳（OC）、钾与有机碳混合（KOC）、钾与钠混合（KNa）、富钾和富 PAHs。富 PAHs 和 KOC 颗粒分别是机动车尾气/煤炭燃烧和生物质燃烧产生的主要颗粒类型，占含 PAHs 颗粒的>50%。研究发现，有机物质在环境大气中增强了含 PAHs 的颗粒，其中富含有机物的（OC 和 KOC）颗粒占>90%。进一步分析表明，由于有机物对 PAHs 的保护和/或含 PAHs 颗粒的老化，PAHs 分数的增加与有机化合物的混合状态有关。本研究的结果提高了我们对大气气溶胶中源自排放源和城市及偏远地区的 PAHs 颗粒的化学组成和混合状态的认识，并提供了现场观测证据，支持了对有机物促进 PAHs 长距离传输的研究。
