Atmospheric Environment最新文献_第8页

Variability of airborne microbial communities and associations with organic pollutants in African air particulate matter across land-use types 非洲不同土地利用类型空气微生物群落的变异及其与空气颗粒物有机污染物的关联

IF 3.7 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2026-02-15 Epub Date: 2025-12-15 DOI: 10.1016/j.atmosenv.2025.121750

Egide Kalisa , Donnabella Lacap-Bugler , Matthew Adams , Jiaqi Bi , Antoine Nsabimana , Gabriel Habiyaremye , Glorieuse Uwizeye , Timothy Lawrence , Kevin Lee , Kazuichi Hayakawa , Stephen Pointing , Stephen DJ. Archer

Exposure to particulate matter (PM) is a major global health concern, yet the potential relationships between its chemical and microbial components remains poorly understood, particularly in rapidly urbanizing, understudied settings. This study presents an integrated assessment of polycyclic aromatic hydrocarbons (PAHs), nitrated PAHs (NPAHs), bacteria, and fungi in both fine (PM₂.₅) and coarse (PM₁₀) aerosols across urban, roadside, and rural sites in sub-Saharan Africa, with a focus on Rwanda across dry and wet seasons. Microbial analysis revealed that the richness and community structure of the airborne bacterial and fungal communities varied with land-use type, linked with PAH/NPAH abundance, PM size fraction, and season. Spearman correlation coefficient confirmed that bacterial communities were more strongly associated with PAH and NPAH compounds, whereas fungal communities were shaped primarily by environmental factors. One bacterial genus, Sphingobium, exhibited evidence of selective enrichment within the PAH rich PM₂.₅ size fraction, highlighting the potential for direct interaction between the biological and chemical compositions in air. We provide a critical baseline for African cities where air quality data are scarce. Current air quality standards, which prioritize chemical thresholds, overlook the biological burden carried by PM.

暴露于颗粒物（PM）是一个主要的全球健康问题，但其化学成分和微生物成分之间的潜在关系仍然知之甚少，特别是在快速城市化和研究不足的环境中。本研究对撒哈拉以南非洲城市、路边和农村地区的细颗粒物（PM2.5）和粗颗粒物（PM10）中的多环芳烃（PAHs）、硝化多环芳烃（NPAHs）、细菌和真菌进行了综合评估，重点关注卢旺达旱季和雨季的情况。微生物分析结果表明，不同土地利用类型的空气中细菌和真菌群落丰富度和群落结构不同，与PAH/NPAH丰度、PM粒径分数和季节有关。Spearman相关系数证实，细菌群落与多环芳烃和NPAH化合物的相关性更强，而真菌群落主要受环境因素的影响。一种细菌属Sphingobium在富含多环芳烃的PM2.5颗粒中表现出选择性富集的证据，突出了空气中生物和化学成分之间直接相互作用的可能性。我们为缺乏空气质量数据的非洲城市提供了一个关键的基线。目前的空气质量标准优先考虑化学阈值，忽视了颗粒物带来的生物负担。

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引用次数: 0

Associations of fine particulate matter and its chemical constituents with outpatient visits for pediatric seizures 细颗粒物及其化学成分与儿科癫痫门诊就诊的关系

IF 3.7 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2026-02-15 Epub Date: 2025-12-16 DOI: 10.1016/j.atmosenv.2025.121751

Tianqi Wang , Shiyu Zhang , Zhenchun Yang , Peng-Chou Tsai , Christine Ladd-Acosta , Yi Wang , Junfeng (Jim) Zhang

Growing epidemiological evidence has reported neurological effects of fine particulate matter (PM_2.5), showing stronger effects of certain PM_2.5 constituents. Among the neurologic outcomes examined so far, pediatric seizure has been rarely assessed. We conducted a time-stratified case-crossover study using pediatric seizure outpatient data from a children's hospital in Shanghai. Individual-level daily concentration of PM_2.5 and its chemical components (black carbon, organic matter, nitrate, sulfate, and ammonium) were estimated with a satellite-based spatiotemporal model. A conditional logistic regression with distributed lag model (DLM) was applied to estimate the associations of PM_2.5 and components with pediatric seizure risk over 14 days preceding to the onset date. Quantile-based g-computation (qgcomp) approach was used to assess the joint effect of a mixture of PM_2.5 components. Analyses were further stratified by sex, age, onset with/without fever, and onset with/without epilepsy. A positive association between PM_2.5 or each of the components, except organic matter, and pediatric seizure onset was observed with lag windows ranging from 0 to 7 days up to 0–14 days. In the multi-pollutant model, per interquartile range (IQR) increase in exposure to the mixture of all five PM_2.5 components were associated with a odds ratio (OR) of 1.03 (95 % CI: 0.95, 2.57). Black carbon and nitrate contributed the most to the positive association, accounting for 47 % and 42 %, respectively. Subgroup analyses showed a larger effect size in children under 5 years old, males, children with concomitant seizure and fever, and children without epilepsy, respectively. Short-term (daily average) exposure to PM_2.5 may be a risk factor for the onset of pediatric seizure. Black carbon and nitrate were the two most important constituents contributing to the PM_2.5 effect. In addition, younger children, males, and children with seizure and fever co-occurring, and children without epilepsy appeared more susceptible.

越来越多的流行病学证据报告了细颗粒物（PM2.5）对神经系统的影响，表明某些PM2.5成分的影响更强。在迄今为止检查的神经系统结果中，儿科癫痫发作很少被评估。我们使用上海一家儿童医院的儿童癫痫门诊数据进行了一项时间分层病例交叉研究。利用基于卫星的时空模型估算PM2.5及其化学成分（黑碳、有机质、硝酸盐、硫酸盐和铵）的个人水平日浓度。采用分布滞后模型（DLM）的条件logistic回归估计PM2.5及其成分与发病前14天儿童癫痫发作风险的关系。采用基于分位数的g计算（qgcomp）方法来评估PM2.5组分混合的联合效应。分析进一步按性别、年龄、发病有无发热、发病有无癫痫进行分层。PM2.5或除有机物外的其他成分与儿童癫痫发作呈正相关，滞后窗范围为0 - 7天至0 - 14天。在多污染物模型中，暴露于所有五种PM2.5成分混合物的每四分位数范围（IQR）增加与比值比（OR）为1.03相关（95% CI: 0.95, 2.57）。黑碳和硝酸盐对正相关贡献最大，分别占47%和42%。亚组分析显示，在5岁以下儿童、男性、伴有癫痫和发热的儿童以及无癫痫的儿童中，效应值更大。短期（每日平均）暴露于PM2.5可能是儿童癫痫发作的一个危险因素。黑碳和硝酸盐是造成PM2.5效应的两个最重要的成分。此外，年龄较小的儿童、男性、癫痫和发烧同时发生的儿童以及没有癫痫的儿童更容易感染。

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引用次数: 0

Quantifying source-specific formaldehyde contributions to photochemical oxidant formation in a highly polluted Chinese megacity 定量分析中国某特大污染城市源特异性甲醛对光化学氧化剂形成的贡献

IF 3.7 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2026-02-15 Epub Date: 2025-12-30 DOI: 10.1016/j.atmosenv.2025.121762

Yunxiang Zhang , Jie Tao , Panru Kang , Dong Zhang , Yifei Xu , Mingkai Wang , Shenbo Wang , Ruiqin Zhang

Formaldehyde (HCHO) critically mediates atmospheric photochemistry, yet its source-specific impacts remain poorly quantified. Integrating Positive Matrix Factorization and Observation-Based Models, we reveal average HCHO concentrations of 5.6 ± 1.6 ppb during ozone (O₃) episodes in Zhengzhou, China, with 43 % originating from RO· + O₂-driven secondary formation. Anthropogenic emission contributes 49 % (e.g., vehicles: 19 %, industry: 16 %). Under Zero-HCHO simulations, concentrations of HO₂·, OH·, and RO₂· decreased by 27 %, 20 %, and 12 %, respectively, with a concomitant 19 % reduction in net O₃ production. Source-specific HCHO reveals that secondary production dominated both ROx· (44–48 % contribution) and net O₃ (52 % contribution) formation. Notably, biogenic HCHO emissions serve a critical function in daytime photochemical oxidant formation (14–18 %) despite its 7 % HCHO share. Diurnal analysis further identifies morning rush-hour emissions of HCHO from vehicles/industries that act as photochemical primers, boosting 22 % and 15 % O₃ formation, respectively. This study provides the mechanistic, source-resolved quantification of HCHO's role in radical cycling and O₃ formation, establishing a critical link between emission sources and photochemical outcomes for targeted pollution control.

甲醛（HCHO）是大气光化学的重要媒介，但其来源特异性影响仍然缺乏量化。综合正矩阵分解和基于观测的模型，我们发现中国郑州臭氧（O3）发作期间的平均HCHO浓度为5.6±1.6 ppb，其中43%来自RO·+ o2驱动的次生地层。人为排放贡献了49%（例如，车辆：19%，工业：16%）。在零hcho模拟下，HO2·、OH·和RO2·的浓度分别下降了27%、20%和12%，同时净O3产量减少了19%。源特异性HCHO表明，次生生产主导了ROx·（贡献44 - 48%）和净O3（贡献52%）地层。值得注意的是，尽管HCHO占7%，但生物源性HCHO排放在白天光化学氧化剂形成中起着关键作用（14 - 18%）。每日分析进一步确定，早高峰时段车辆/工业排放的HCHO作为光化学引物，分别促进22%和15%的O3形成。本研究为HCHO在自由基循环和O3形成中的作用提供了机制和来源解析的量化，为有针对性的污染控制建立了排放源与光化学结果之间的关键联系。

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引用次数: 0

Characterizing diurnal variations and driving factors of major gaseous pollutants across China 中国主要气态污染物的日变化特征及其驱动因素

IF 3.7 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2026-02-15 Epub Date: 2025-12-24 DOI: 10.1016/j.atmosenv.2025.121759

Junli Liu , Yang Qian , Siyuan Wang , Weiwei Gu , Danhuai Guo

Gaseous air pollutants pose significant threats to environmental quality and public health, with their diurnal variation patterns critically determining human exposure and health risks. However, the spatiotemporal dynamics and driving factors of these variations remain insufficiently understood at the national level. This study characterizes the diurnal variation of four key pollutants (SO₂, NO₂, CO, and O₃), using hourly observations from 1636 monitoring stations across China spanning 2014–2024. By integrating a Light Gradient Boosting Machine (LightGBM) model with SHapley Additive exPlanations (SHAP), we quantified the non-linear contributions of meteorological, topographic, and socioeconomic drivers to pollutant variability, with the robustness of the results verified through spatial sensitivity analysis. The results reveal pronounced spatial and seasonal heterogeneity in diurnal ranges. Specifically, SO₂ is shaped by the synergy of socioeconomic and meteorological factors; NO₂ is dominated by socioeconomic intensity but amplified by plateau meteorology; CO is driven by high-frequency emission cycles such as traffic patterns; and O₃ is strictly regulated by solar radiation and topography. These findings elucidate the distinct roles of emission intensity, atmospheric stability, and chemical processing in shaping diurnal cycles, underscoring the necessity of region-specific and time-targeted mitigation strategies to minimize population exposure and advance precision air-quality management.

气态空气污染物对环境质量和公众健康构成重大威胁，其日变化模式关键地决定了人类接触和健康风险。然而，在国家层面上，对这些变化的时空动态和驱动因素的了解仍然不够充分。本研究利用2014-2024年中国1636个监测站逐小时观测数据，分析了四种主要污染物（SO2、NO2、CO和O3）的日变化特征。通过将光梯度增强机（LightGBM）模型与SHapley加性解释（SHAP）相结合，我们量化了气象、地形和社会经济驱动因素对污染物变异的非线性贡献，并通过空间敏感性分析验证了结果的稳健性。结果表明，日较差具有明显的空间和季节异质性。具体而言，SO2是由社会经济因素和气象因素共同作用形成的；NO2以社会经济强度为主，高原气象强度放大；二氧化碳是由交通模式等高频排放周期驱动的；O3受太阳辐射和地形的严格调控。这些发现阐明了排放强度、大气稳定性和化学过程在形成日循环中的独特作用，强调了采取针对特定区域和有时间目标的缓解战略以最大限度地减少人口暴露和推进精确空气质量管理的必要性。

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引用次数: 0

Study the effect of photochemical processes on VOC source apportionment at a site in the Pearl River Estuary of southern China 研究光化学过程对珠江口某地点VOC源分配的影响

IF 3.7 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2026-02-15 Epub Date: 2025-12-03 DOI: 10.1016/j.atmosenv.2025.121718

Guizhen Fang , Yee Jun Tham , Lili Ming , Bing Wu , Jiayin Sun , Danna Zhao , Cuizhi Sun , Ying Yang , Haoyu Jiang , Haichao Wang , Shichun Zou , Yuan Gao , Zhenhao Ling

To advance the understanding of the characteristics and photochemical processes of VOCs in the Pearl River Estuary (PRE), an intensive field measurement campaign was conducted at an island site (Da Wan Shan Island, DWS) in winter, using a proton transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS). A total of 133 VOC species were identified, with a mean total VOC mixing ratio of 8.2 ± 5.3 ppbv. Oxygenated VOCs (OVOCs), particularly C_xH_yO₁ (55.0 %) and C_xH_yO₂ (21.0 %) dominated the VOCs. Although the level of total VOCs was lower at DWS than that typically observed in the inland Pearl River Delta (PRD) region, distinct temporal and diurnal variations of VOCs were found in scenarios of different air masses (i.e., continental outflow (Scenarios A1 and A2) and marine air masses (Scenario A3)), which had undergone different degrees of photochemical processes. This indicated different photochemical evolutions and sources of VOCs. The source apportionment results of PMF with the input of initial (IC-PMF) and observed concentrations (OC-PMF) were compared to further evaluate the influence of photochemical consumption on the source apportionment results. We found that photochemical oxidation not only causes changes in VOC concentration and composition but also affects the source characteristics of VOCs. Through the IC-PMF results, vehicle + solid fuel combustion and liquid petroleum gas (LPG)-related emissions had higher contributions in continental outflow air masses of Scenarios A1 (12.6 % and 21.1 %) and A2 (16.9 % and 13.9 %), but only 3.3 % and 4.1 % in marine air masses (Scenarios A3), indicating that anthropogenic sources remain significant in PRD and PRE. Our study shows that outflow air masses from the PRD region has been through active photochemical processes, which can degrade the air quality over PRE, emphasizing the urgent need for mitigation of VOC emissions to reduce the photochemical pollution in this region.

为了进一步了解珠江口（PRE） VOCs的特征及其光化学过程，利用质子转移反应飞行时间质谱仪（PTR-ToF-MS）于冬季在大湾山岛（DWS）进行了大量野外测量。共鉴定出133种VOC，平均总VOC混合比为8.2±5.3 ppbv。含氧VOCs （OVOCs）以CxHyO1（55.0%）和CxHyO2（21.0%）为主。虽然DWS的总VOCs水平低于珠三角内陆地区的典型观测值，但不同气团（即大陆外流气团（A1和A2）和海洋气团（A3））经历了不同程度的光化学过程，其VOCs的时间和日变化差异明显。这表明VOCs的光化学演化和来源不同。将输入初始浓度（IC-PMF）和观测浓度（OC-PMF）的PMF源分配结果进行比较，进一步评价光化学消耗对源分配结果的影响。我们发现光化学氧化不仅会引起VOC浓度和组成的变化，还会影响VOCs的来源特征。通过IC-PMF的结果，车辆+固体燃料燃烧和液化石油气（LPG）相关排放在情景A1（12.6%和21.1%）和A2（16.9%和13.9%）的大陆流出气团中贡献更高，但在情景A3的海洋气团中贡献仅为3.3%和4.1%，表明人为源在珠三角和PRE中仍然重要。我们的研究表明，从珠三角地区流出的气团已经通过活跃的光化学过程，可以降低PRE的空气质量，强调迫切需要减少VOC的排放，以减少该地区的光化学污染。

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引用次数: 0

Local industrial δ18O signatures refine carbon monoxide source apportionment and prevent overestimation of primary emissions in a typical industrial city 在一个典型的工业城市，局部工业δ18O特征改进了一氧化碳源的分配，并防止了一次排放的高估

IF 3.7 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2026-02-15 Epub Date: 2025-12-19 DOI: 10.1016/j.atmosenv.2025.121755

Kai Xie , Yulong Yan , Jiaqi Dong , Lin Peng

Carbon monoxide (CO) is a trace gas that affects atmospheric oxidative capacity and climate change, making accurate source apportionment crucial. Here, for the first time, we identified the isotopic signatures (δ¹⁸O) of industrial-related CO sources in Changzhi of Northern China. And total 21 ambient CO samples were collected from July 17 to July 21, 2023 with the duration of 2 h. These signatures were integrated with the Stable Isotope Analysis in R (MixSIAR) model to apportion CO sources. During the observation period, the average CO mixing ratio was 0.73 ± 0.26 ppm, which exceeded the summer average levels in both China and globally. Industrial-related sources exhibited distinct δ¹⁸O enrichment (24.5 ± 1.0 ‰ for steel industry to 29.2 ± 0.1 ‰ for heavy-duty diesel trucks). They are clearly separated from existed δ¹⁸O signatures from secondary formation and vehicle sources, thus providing essential reference data for isotopic source apportionment. The δ¹⁸O values of ambient CO varied by 3.5 ‰ overall, while diurnal fluctuations were minor (approximately 0.3 ‰), indicating relative stability on diurnal scale. Incorporating industrial-related isotopic signatures into MixSIAR, contribution of primary emissions decreased from 73.6 % to 56.0 %. These results indicate only based on existed source spectra (non-methane hydrocarbons oxidation and light-duty vehicle emissions) substantially overestimate the contribution of primary sources. These findings fill a knowledge gap concerning the isotopic signatures of industrial CO emissions and emphasize the importance of incorporating localized isotopic signatures into source apportionment. This work also provides basis for developing targeted mitigation strategies in industrial cities.

一氧化碳（CO）是一种影响大气氧化能力和气候变化的微量气体，因此准确的来源分配至关重要。本文首次确定了长治地区工业相关CO源的δ18O同位素特征。在2023年7月17日至7月21日共采集了21份环境CO样品，持续时间为2 h。这些特征与R （MixSIAR）稳定同位素分析模型相结合，用于CO源的分配。观测期内平均CO混合比为0.73±0.26 ppm，超过了中国和全球夏季平均水平。工业相关来源表现出明显的δ18O富集（钢铁工业为24.5±1.0‰，重型柴油卡车为29.2±0.1‰）。它们与次生地层和车辆源的δ18O特征明显分离，为同位素源分配提供了重要的参考资料。大气CO的δ18O值变化幅度总体为3.5‰，日变化幅度较小（约为0.3‰），在日尺度上相对稳定。在MixSIAR中加入工业相关的同位素特征，一次排放的贡献从73.6%下降到56.0%。这些结果表明，仅基于现有的源光谱（非甲烷烃氧化和轻型汽车排放）大大高估了一次源的贡献。这些发现填补了有关工业CO排放同位素特征的知识空白，并强调了将局部同位素特征纳入源分配的重要性。这项工作还为工业城市制定有针对性的缓解战略提供了依据。

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引用次数: 0

The association between indoor VOCs exposure and lung function in adult asthma patients and the mediating effect of metabolites 成人哮喘患者室内VOCs暴露与肺功能的关系及代谢物的中介作用

IF 3.7 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2026-02-15 Epub Date: 2025-12-16 DOI: 10.1016/j.atmosenv.2025.121749

Miao Yu , Dongxia Jiang , Ying Shang , Zhengxiong Li , Chun Chang , Shaodan Huang

The health effects of combined exposure to indoor volatile organic compounds (VOCs) on lung function in adults with asthma remain unclear, and the underlying metabolic mechanisms are incompletely understood. In this panel study, 53 adult asthma patients underwent repeated home visits where indoor air samples were collected for VOC measurement, lung function was assessed, and exhaled breath condensate samples were obtained for untargeted metabolomic analysis. We used linear mixed effects models to evaluate associations between individual VOCs and lung function parameters. VOCs exhibiting significant individual effects were further analyzed using quantile g-computation and Bayesian kernel machine regression models to assess combined exposure effects and identify key contributors. Metabolic pathways were explored through mediation analysis. The linear mixed effects models identified 11 VOC components significantly and negatively associated with lung function: methacrolein, acetone, butyl acetate, toluene, ethylbenzene, styrene, trichloroethylene, tetrachloroethylene, n-hexane, octane, and hexadecane. The quantile g-computation model revealed a significant negative joint effect of these VOCs on lung function, with ethylbenzene and methacrolein contributing most substantially. These findings were corroborated by the Bayesian kernel machine regression model, supporting the robustness of the results. Mediation analysis demonstrated that proline, glycine, putrescine, and phenylethanolamine mediated the effect of trichloroethylene on reduced percent predicted peak expiratory flow, accounting for 31.0 %–41.6 % of the total effect. In conclusion, combined exposure to indoor VOCs adversely affects lung function in adults with asthma, mediated in part by specific metabolites. These findings underscore the importance of addressing indoor air quality in asthma management strategies.

室内挥发性有机化合物（VOCs）联合暴露对哮喘成人肺功能的健康影响尚不清楚，其潜在的代谢机制也不完全清楚。在这项小组研究中，53名成年哮喘患者进行了多次家访，收集室内空气样本进行VOC测量，评估肺功能，并获得呼出液样本进行非靶向代谢组学分析。我们使用线性混合效应模型来评估个体挥发性有机化合物与肺功能参数之间的关系。使用分位数g计算和贝叶斯核机回归模型进一步分析具有显著个体效应的挥发性有机化合物，以评估综合暴露效应并识别关键贡献者。通过中介分析探索代谢途径。线性混合效应模型确定了与肺功能显著负相关的11种VOC成分：甲基丙烯、丙酮、乙酸丁酯、甲苯、乙苯、苯乙烯、三氯乙烯、四氯乙烯、正己烷、辛烷和十六烷。分位数g计算模型显示，这些挥发性有机化合物对肺功能有显著的负联合影响，其中乙苯和甲基丙烯的影响最大。这些发现被贝叶斯核机回归模型证实，支持结果的鲁棒性。中介分析表明，脯氨酸、甘氨酸、腐胺和苯乙醇胺介导了三氯乙烯对预期呼气峰流量降低的影响，占总效应的31.0% - 41.6%。综上所述，室内VOCs联合暴露对哮喘成人肺功能产生不利影响，部分由特定代谢物介导。这些发现强调了在哮喘管理策略中处理室内空气质量的重要性。

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引用次数: 0

A comprehensive risk assessment of non-dioxin-like and dioxin-like PCBs in indoor and outdoor dust from Hefei, China 合肥市室内外粉尘中非类二恶英和类二恶英多氯联苯的综合风险评估

IF 3.7 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2026-02-15 Epub Date: 2025-12-16 DOI: 10.1016/j.atmosenv.2025.121740

Mengchen Shen , Li Zhou , Guijian Liu , Ruijia Liu , Hao Yin , Yanyun Hu , Muhammad Arif , Qing Zhang

Airborne contamination by non-dioxin-like (NDL) and dioxin-like (DL) polychlorinated biphenyls (PCBs) is a prevalent and significant issue affecting industrial cities worldwide and is a potential health hazard for humans and wildlife. This study investigates the contamination and health risks of polychlorinated biphenyls (PCBs) in indoor and outdoor dust from Hefei, China. The mean concentrations of ΣNDL-PCBs were 56.27 ng/g and 7.47 ng/g for indoor and outdoor dust, respectively, while ΣDL-PCBs averaged 98.81 ng/g in indoor dust and 92.86 ng/g in outdoor dust. A probabilistic health risk assessment was conducted for different age groups. The results revealed distinct PCB distribution patterns, with PCBs primarily concentrated in finer particle sizes (26–62 μm) indoors compared to outdoors (>62 μm). The health risk assessment is based on a probabilistic human health risk assessment model developed by Monte Carlo simulation methodology for five different age groups, highlighting the acceptable noncarcinogenic health effects indicated by the hazard index (HI) values. The Monte Carlo simulation was conducted with 10,000 iterations, and the 95 % confidence interval was used to express the uncertainty of the risk estimates. Exposure parameters, such as the dust intake rate, body weight, and exposure parameter, were incorporated as probabilistic inputs based on established literature or survey data. However, concerning indoor dust, the study raises concerns regarding infants' exposure to DL-PCBs and NDL-PCBs, with a total cancer risk (TCR) probability close to 5 % and exceeding the acceptable risk level of 1.00E-6 as defined by the US EPA. DL-PCBs consistently demonstrated higher hazard index and TCR values than NDL-PCBs across all scenarios. These findings highlight health concern for infants and underscore the need for targeted strategies to mitigate PCB contamination and reduce exposure, particularly in indoor environments.

非类二恶英（NDL）和类二恶英（DL）多氯联苯（PCBs）的空气污染是影响全球工业城市的一个普遍而重要的问题，对人类和野生动物都是潜在的健康危害。本研究调查了合肥市室内外粉尘中多氯联苯（PCBs）的污染及健康风险。室内、室外粉尘浓度ΣNDL-PCBs平均值分别为56.27 ng/g和7.47 ng/g，室内粉尘浓度ΣDL-PCBs平均值为98.81 ng/g，室外粉尘浓度为92.86 ng/g。对不同年龄组进行了概率健康风险评估。结果显示不同的PCB分布模式，与室外（>62 μm）相比，室内PCB主要集中在更细的粒径（26-62 μm）。健康风险评估基于蒙特卡罗模拟方法为五个不同年龄组开发的概率人类健康风险评估模型，突出了危害指数（HI）值所表明的可接受的非致癌健康影响。采用蒙特卡罗模拟法进行10000次迭代，采用95%置信区间表示风险估计的不确定性。暴露参数，如吸尘率、体重和暴露参数，被纳入基于既定文献或调查数据的概率输入。然而，关于室内粉尘，该研究提出了对婴儿暴露于DL-PCBs和NDL-PCBs的担忧，总癌症风险（TCR）概率接近5%，超过了美国环保署定义的可接受风险水平1.00E-6。在所有情况下，dl - pcb的危害指数和TCR值始终高于ndl - pcb。这些发现突出了婴儿的健康问题，并强调需要有针对性的战略来减轻多氯联苯污染和减少接触，特别是在室内环境中。

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引用次数: 0

Secondary organic aerosol formation in the arctic (Ny-Ålesund) atmosphere during summer: inferences from water-soluble dicarboxylic acids and related compounds 夏季北极（Ny-Ålesund）大气中二次有机气溶胶的形成：来自水溶性二羧酸和相关化合物的推论

IF 3.7 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2026-02-15 Epub Date: 2025-12-10 DOI: 10.1016/j.atmosenv.2025.121737

Suresh K. R. Boreddy, Prashant Hegde, Mukunda M. Gogoi, S. Suresh Babu

High-latitude regions are particularly susceptible to the impacts of climate change and global warming. Organic aerosols are widespread and play a vital role in the Earth's climate; therefore, monitoring their molecular distributions, sources, and formation processes is essential. The present study investigates water-soluble dicarboxylic acids and related secondary organic compounds in aerosols from the Gruvebadet observatory in Ny-Ålesund during summer 2023 to gain insights into the formation processes of secondary organic aerosols (SOA) in the Arctic atmosphere. The results indicate that oxalic acid (C₂) was the most abundant, followed by succinic (C₄) and phthalic (Ph) acids, as well as malonic (C₃) and azelaic (C₉) acids. The higher abundance of C₄ over C₃ (on average) suggests relatively fresh emission sources. The high fumaric-to-maleic (F/M) ratios (mean: 1.14 ± 0.46) and diacids-C/TC ratios (16.4 ± 6.67 %) indicate that photochemical processes were a significant source of diacids throughout the sampling period. The mass diagnostic ratios indicate that the photochemical oxidation of unsaturated fatty acids (UFAs) enriched in the sea-surface micro-layer is the primary source of SOA, followed by the oxidation of aromatic hydrocarbons (AHCs). Furthermore, quantification of C₂ associated with the photooxidation of UFAs was conducted using a linear relationship-based approach. The results show that on average, 61 ± 20 % (range: 9–83 %) of C₂ was derived from the oxidation of UFAs, with the rest was attributed to the photooxidation of AHCs. The present study also highlighted potential uncertainties in using regression-based source apportionment of C₂ with bootstrap analysis. These findings will improve our understanding of the transformation processes of organic aerosols, which are vital for climate modellers to accurately estimate SOA mass and its climatic effects, especially in the Arctic environment.

高纬度地区特别容易受到气候变化和全球变暖的影响。有机气溶胶分布广泛，在地球气候中起着至关重要的作用；因此，监测它们的分子分布、来源和形成过程是必不可少的。本研究调查了2023年夏季美国Ny Gruvebadet观测站-Ålesund气溶胶中的水溶性二羧酸和相关的二次有机化合物，以深入了解北极大气中二次有机气溶胶（SOA）的形成过程。结果表明，草酸（C2）含量最多，其次为琥珀酸（C4）和邻苯二甲酸（Ph），丙二酸（C3）和壬二酸（C9）。C4的丰度高于C3（平均），表明排放源相对较新鲜。富马/马来酸（F/M）比值（平均值：1.14±0.46）和二酸- c /TC比值（16.4±6.67%）表明，在整个采样期间，光化学过程是二酸的重要来源。质量诊断比值表明，海洋表层微层富集的不饱和脂肪酸（UFAs）的光化学氧化是SOA的主要来源，其次是芳香烃（AHCs）的氧化。此外，使用基于线性关系的方法对与ufa光氧化相关的C2进行了量化。结果表明，平均61±20%（范围：9 - 83%）的C2来源于ufa的氧化，其余来源于AHCs的光氧化。本研究还强调了使用基于回归的C2源分配与bootstrap分析的潜在不确定性。这些发现将提高我们对有机气溶胶转化过程的理解，这对于气候建模者准确估计SOA质量及其气候影响至关重要，特别是在北极环境中。

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引用次数: 0

Atmospheric boundary layer characteristics during severe air pollution and fog events over Delhi: Insights from ground-based Lidar, satellites, and models 德里严重空气污染和雾事件期间的大气边界层特征：来自地面激光雷达、卫星和模型的见解

IF 3.7 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2026-02-15 Epub Date: 2025-11-20 DOI: 10.1016/j.atmosenv.2025.121684

Dharmendra Kumar Kamat , Som Kumar Sharma , Prashant Kumar , Kondapalli Niranjan Kumar , Sourita Saha , Aniket , Sukhwinder Kaur , Arun

Delhi experiences severe air quality deterioration during the post-monsoon and winter seasons, driven by anthropogenic emissions and natural meteorological factors. This study investigates the atmospheric boundary layer (ABL) characteristics during heavy air pollution and fog conditions over Delhi from October 2023 to February 2024 using ground-based Lidar, satellite, and reanalysis data. Lidar measurements reveal a persistently shallow ABL (<1 km) from November to January, with nighttime boundary layer height (BLH) suppressed by strong radiative inversions. Elevated PM_2.5 concentrations during this period show an inverse, power-law relationship with BLH. The ventilation coefficient (VC) remained below 800 m²s^-1 from November to January, indicating poor dispersion. INSAT-3D/3DR satellite data showed a peak fog occurrence of 75 % over Delhi, with the highest frequency in January. Analysis showed that the combined frequency of haze, fog, and low-level clouds reached 22.46 % during the study period, with the highest occurrences in November (45.10 %) and January (39.55 %). Ground-based Lidar observations captured fine-scale features such as shallow inversion layers, nighttime ABL collapse, and diurnal boundary layer development more accurately than reanalysis. These insights are crucial for enhancing urban weather models, air quality forecasts, and early warning systems in pollution-affected regions.

在人为排放和自然气象因素的推动下，德里在季风后和冬季经历了严重的空气质量恶化。本研究利用地面激光雷达、卫星和再分析数据，研究了2023年10月至2024年2月德里重污染和雾条件下的大气边界层（ABL）特征。激光雷达测量显示，从11月到1月，一个持续的浅ABL (<1 km)，夜间边界层高度（BLH）被强辐射逆温抑制。在此期间，PM2.5浓度升高与BLH呈反比的幂律关系。11 -1月通风系数（VC）保持在800 m2s-1以下，散度较差。INSAT-3D/3DR卫星数据显示，德里的雾峰值发生率为75%，一月份的频率最高。分析表明，霾、雾和低层云在研究期间的总频率达到22.46%，其中11月（45.10%）和1月（39.55%）出现频率最高。地面激光雷达观测比再分析更准确地捕获了诸如浅层逆温层、夜间ABL塌陷和日边界层发展等精细尺度特征。这些见解对于加强城市天气模型、空气质量预报和污染影响地区的早期预警系统至关重要。

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引用次数: 0