Air pollution, particularly high ambient particulate matter (PM) concentrations, poses a serious public health concern in South Korea. This study analyzed 139 daily PM samples collected from an urban site in Seoul between March 2018 and January 2020. This study aimed to quantify the chemical composition of PM and identify the source characteristics. The average PM mass concentration for the entire study period was 25.3 μg m. The chemical composition was dominated by ionic particles (13.2 μg m, 52%), carbonaceous particles (7.0 μg m, 28%), and trace elements (0.5 μg m, 2%). The Positive Matrix Factorization (PMF) model was employed to identify PM sources using quality-controlled sampling data after eliminating factors that could adversely affect the modeling. Seven sources were resolved through PMF, applying a trial-and-error method to determine the optimal number of sources. The PMF modeling results indicated that secondary sulfate (28%) was the largest contributor, followed by internal factors (23%), secondary nitrate (19%), soil (14%), biomass burning (9%), and aged sea salt (7%). As an additional case study, the analysis of backward trajectories for the winter of 2018, which had the highest PM concentrations, revealed that the air current carrying PM had passed from the northwest region of Seoul. Particulary, source identification for this winter case resulted in the highest secondary nitrate across all study periods. This more specific interpretation of the pollutant characteristics of PM in Seoul could aid in developing effective control strategies and policies for air pollution mitigation.

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2018-2020年首尔PM2.5化学成分及来源解析

空气污染，特别是环境颗粒物 (PM) 浓度较高，在韩国构成了严重的公共卫生问题。本研究分析了 2018 年 3 月至 2020 年 1 月期间从首尔市区采集的 139 个每日 PM 样本。本研究旨在量化 PM 的化学成分并确定来源特征。整个研究期间的平均PM质量浓度为25.3 μg m。化学成分主要为离子颗粒（13.2 μg m，52%）、碳质颗粒（7.0 μg m，28%）和微量元素（0.5 μg m，2%）。在消除可能对建模产生不利影响的因素后，采用正矩阵分解 (PMF) 模型使用质量控制的采样数据来识别 PM 源。通过 PMF 解决了七个源，应用试错法来确定最佳源数量。PMF模型结果表明，次生硫酸盐（28%）是最大的贡献者，其次是内部因素（23%）、次生硝酸盐（19%）、土壤（14%）、生物质燃烧（9%）和老化海盐(7%)。作为另一个案例研究，对 2018 年冬季 PM 浓度最高的向后轨迹分析表明，携带 PM 的气流是从首尔西北部地区经过的。特别是，这个冬季案例的来源识别导致所有研究期间的次生硝酸盐含量最高。对首尔 PM 污染物特征的更具体解释可能有助于制定有效的控制策略和减轻空气污染的政策。