Park Shin-Young, Cho Yong-Sung, Jang Hyeok, Kwon Jaymin, Yoon Sung Won, Lee Cheol-Min
Department of Environmental & Chemical Engineering, Seokyeong University, Seoul, Korea.
Department of Public Health, California State University, Fresno, USA.
Sci Rep. 2025 Jul 2;15(1):23529. doi: 10.1038/s41598-025-99353-6.
The coronavirus disease 2019 (COVID-19) pandemic was reported to improve air quality. However, the effects of lockdown on PM₂.₅ and its chemical components based on source-specific characteristics remain unclear. This study evaluated and compared the components of PM₂.₅ across three target sites-Seoul, Ansan-Siheung, and Wonju-based on source distribution patterns during the pandemic and post-pandemic periods. The results revealed that total ion concentrations decreased by 7-19% at the target sites, while trace element concentrations increased by 19-29% in the post-pandemic period. Carbon concentrations showed region-specific trends. Components associated with secondary formation, such as SO₄²⁻, NO₃⁻, and NH₄⁺, decreased, whereas natural-origin components, such as Cl⁻, Na⁺, Mg²⁺, and Ca²⁺, increased, indicating enhanced dust resuspension. Furthermore, a positive matrix factorization (PMF) analysis demonstrated a predominance of primary emission sources and resuspended dust in the post-pandemic period, with a decline in contributions from secondary formation sources. These regional variations were primarily influenced by the extent of socioeconomic activities, with Seoul exhibiting a higher contribution from primary emissions and suspended dust. This study emphasizes the importance of establishing region-specific air quality improvement policies by scientifically identifying the impacts of anthropogenic activity on PM₂.₅ components and their sources.
据报道，2019冠状病毒病（COVID-19）大流行改善了空气质量。然而，基于源特定特征的封锁对细颗粒物（PM₂.₅）及其化学成分的影响仍不明确。本研究根据大流行期间和大流行后时期的源分布模式，对首尔、安山-始兴和原州这三个目标地点的PM₂.₅成分进行了评估和比较。结果显示，目标地点的总离子浓度下降了7%-19%，而在大流行后时期，微量元素浓度上升了19%-29%。碳浓度呈现出区域特定趋势。与二次形成相关的成分，如SO₄²⁻、NO₃⁻和NH₄⁺减少，而天然来源成分，如Cl⁻、Na⁺、Mg²⁺和Ca²⁺增加，表明扬尘再悬浮增强。此外，正矩阵因子分解（PMF）分析表明，在大流行后时期，主要排放源和再悬浮灰尘占主导地位，二次形成源的贡献下降。这些区域差异主要受社会经济活动程度的影响，首尔的主要排放和悬浮灰尘贡献更高。本研究强调了通过科学确定人为活动对PM₂.₅成分及其来源的影响来制定区域特定空气质量改善政策的重要性。
