Froment, Jean Park, Jong-Uk Kim, Sang-Woo Cho, Yoonjin Choi, Soobin Seo, Young Hun Baik, Seungyun Lee, Ji Eun Martin, Jonathan W. 2025-02-20T06:00:05Z 2025-02-20T06:00:05Z 2025-02-09 2025-02 0013-936X https://pubs.kist.re.kr/handle/201004/151766 The complex and dynamic nature of airborne fine particulate matter (PM2.5) has hindered understanding of its chemical composition, sources, and toxic effects. In the first steps of a larger study, here, we aimed to elucidate relationships between source regions, ambient conditions, and the chemical composition in water extracts of PM2.5 samples (n = 85) collected over 16 months at an observatory in the Yellow Sea. In each extract, we quantified elements and major ions and profiled the complex mixtures of organic compounds by nontarget mass spectrometry. More than 50,000 nontarget features were detected, and by consensus of in silico tools, we assigned a molecular formula to 13,907 features. Oxygenated compounds were most prominent, followed by mixed nitrogenated/oxygenated compounds, organic sulfates, and sulfonates. Spectral matching enabled identification or structural annotation of 43 substances, and a workflow involving SIRIUS and MS-DIAL software enabled annotation of 74 unknown per- and polyfluoroalkyl substances with primary source regions in China and the Korean Peninsula. Multivariate modeling revealed seasonal variations in chemistry, attributable to the combination of warmer temperatures and maritime source regions in summer and to cooler temperatures and source regions of China in winter. English American Chemical Society Exploring the Chemical Complexity and Sources of Airborne Fine Particulate Matter in East Asia by Nontarget Analysis and Multivariate Modeling Article 10.1021/acs.est.4c09615 1 Environmental Science & Technology, v.59, no.5, pp.2623 - 2640 Environmental Science & Technology 59 5 2623 2640 N scie scopus 001409543600001 Engineering, Environmental Environmental Sciences Engineering Environmental Sciences & Ecology Article POLYFLUOROALKYL SUBSTANCES PM2.5 WATER EMISSIONS PM2.5 air pollution high-resolutionmass spectrometry nontarget sources PFAS