Journal of Atmospheric Chemistry最新文献

{"title":"Seasonal variations and sources of HONO in suburban Beijing: Implications for secondary pollution control","authors":"Yunfeng Li,&nbsp;Minghao Dong,&nbsp;Xiaoyang Liu,&nbsp;Yafei Wang,&nbsp;Hong Li,&nbsp;Rui Gao","doi":"10.1007/s10874-026-09500-0","DOIUrl":"10.1007/s10874-026-09500-0","url":null,"abstract":"<div><p>Nitrous acid (HONO), a key atmospheric component, plays an important role in hydroxyl radical (OH) production and secondary pollutant formation. To identify the concentrations, sources, and roles of HONO under different pollution conditions, we measured HONO and other pollutant concentrations in suburban Beijing during summer and autumn 2023. Significantly higher HONO concentrations occurred during a summer ozone pollution episode (PE2: 0.74 ppbv) and an autumn haze episode (PE4: 1.99 ppbv) relative to the corresponding clean periods in summer (PE1: 0.59 ppbv) and autumn (PE3: 0.69 ppbv). Vehicle emissions were not the primary source of HONO during the four episodes. During PE1 and PE2 daytime HONO production, unknown sources (68%) dominated, while the homogeneous NO + OH reaction (37.70%) predominated during PE3. During PE4, particulate nitrate photolysis (32.59%) accounted for the largest daytime source, followed by the homogeneous NO + OH reaction (24.75%). Nighttime HONO formation was primarily driven by heterogeneous NO₂ conversion on ground surfaces, with an enhanced contribution from aerosol surfaces during the haze episode. Heterogeneous NO₂ conversion reactions with higher uptake coefficients could not fully explain the unknown sources during PE1 and PE2. The strong correlation between the unknown sources and the photolysis coefficient suggested the involvement of light-driven processes during summer. HONO photolysis (41%–66%) consistently produced more OH radicals than O₃ photolysis, but O₃ photolysis (49%) was also an important contributing factor during PE2. Elevated HONO during pollution episodes may enhance the atmospheric oxidation capacity via OH production, thereby favoring secondary pollutant formation. </p></div>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"83 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148837410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Size-fractionated PM-bound metals and associated health risks in the densely populated megacity of Southern Vietnam: a preliminary investigation","authors":"Le Quoc Hau,&nbsp;Nguyen Duy Dat,&nbsp;Nhung Thi-Tuyet Hoang,&nbsp;Giang Tien Nguyen,&nbsp;Perapong Tekasakul,&nbsp;Racha Dejchanchaiwong,&nbsp;Ly Sy Phu Nguyen","doi":"10.1007/s10874-026-09499-4","DOIUrl":"10.1007/s10874-026-09499-4","url":null,"abstract":"<div><p>Size-fractionated particulate matter analysis is key to understanding how particle size influences health risks. However, data on metals distribution and respiratory deposition across PM sizes in Southeast Asia is still scarce. In this study, we evaluated the levels, size distribution, and health-related impacts of metals in particulate matter (PM) from Ho Chi Minh City (HCMC), the most densely populated urban in Southern Vietnam. Sampling was performed monthly with a five-stage nano-sampler (PM_&lt; 0.5, PM_0.5−1, PM_1−2.5, PM_2.5−10, and PM_&gt; 10). Concentrations of 8 metals were analyzed by ICP-MS, and the levels were observed in the following order: Al (1741 ng m^− 3) &gt; Fe (958 ng m^− 3) &gt; Zn (731 ng m^− 3) &gt; Pb ( 22.6 ng m^− 3) &gt; Mn (21.3 ng m^− 3) &gt; Cu (19.4 ng m^− 3) &gt; Ni ( 4.86 ng m^− 3) &gt; Cd (0.52 ng m^− 3). Crustal metals (Al and Fe) predominantly resided in the coarse particulate fraction, whereas anthropogenic metals (e.g. Pb, Zn, and Cd) were enriched in fine particles. Deposition modeling indicated that crustal metals were mostly retained in the head region (62–72%), while anthropogenic metals were deposited more in deeper lung regions (7–12%). The health risk assessment showed that the Hazard Index (HI) was markedly higher in children than in adults for both PM_2.5 and PM₁₀. Specifically, the HI for children was 1.95 for PM_2.5 and 3.54 for PM₁₀, whereas for adults, these values were 0.49 and 0.88, respectively. Regarding cancer risk, Total Cancer Risk (TCR) for children reached 1.31 × 10^− 5 for PM_2.5 and 1.75 × 10^− 5 for PM₁₀, exceeding the low-risk threshold. In contrast, the TCR for adults was considerably lower at 3.26 × 10^− 6 and 3.0 × 10^− 6. These findings indicated the importance of size-resolved PM studies to better understand exposure characteristics and potential health risks posed by toxic elemental contaminants.</p></div>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"83 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148750914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonality of isoprene emission from sixteen dominant tropical tree species in Central India","authors":"Tanzil Gaffar Malik,&nbsp;Sudhir Kumar Pandey,&nbsp;Wan Shafrina Wan Mohd Jaafar,&nbsp;Andrea Clavijo McCormick,&nbsp;Lokesh Kumar Sahu,&nbsp;Ankesh Tiwari,&nbsp;Rashmi Dubey,&nbsp;Bilal Ahmad Mir,&nbsp;Khalid Rehman Hakeem,&nbsp;Annisa Utami Rauf","doi":"10.1007/s10874-026-09498-5","DOIUrl":"10.1007/s10874-026-09498-5","url":null,"abstract":"<div><p>Isoprene is one of the most abundant biogenic volatile organic compounds (BVOCs) emitted by plants and plays a key role in atmospheric chemistry. However, seasonally resolved, species-specific outdoor enclosure-based sapling measurements in tropical ecosystems remain scarce. In this study, isoprene emission rates from sixteen dominant tropical tree species in Central India were characterized across summer, rainy, and winter seasons using a dynamic enclosure chamber with potted saplings at GGV Campus, Bilaspur. Isoprene emissions peaked in summer, contributing 52% of total annual emissions, followed by rainy (27%) and winter (21%) seasons. Among the species studied, <i>Eucalyptus globulus</i> exhibited the highest standard emission rate during summer. Emissions showed strong positive correlations with temperature (TEM) and photosynthetically active radiation (PAR), while correlations with relative humidity (RH) and carbon dioxide (CO₂) were generally weak. The observed seasonal variability reflects the combined influence of meteorological drivers and species-specific emission capacities. This study provides regionally relevant standard emission factors (Eₛ) for key tropical species in Central India, which can support improved modeling of BVOC emissions and regional atmospheric chemistry. These results represent controlled outdoor sapling measurements and should not be interpreted as mature forest canopy fluxes; the absolute emission values should therefore be treated as method-constrained estimates.</p></div>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"83 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unraveling O3 formation drivers in a Yangtze River Delta city under stagnant conditions: a PMF, meteorological normalization, and machine learning framework","authors":"Lei Tong,&nbsp;Weicheng Tong,&nbsp;Dan Li,&nbsp;Dingming Xue,&nbsp;Yang Meng,&nbsp;Mengmeng He,&nbsp;Hang Xiao","doi":"10.1007/s10874-026-09497-6","DOIUrl":"10.1007/s10874-026-09497-6","url":null,"abstract":"<div><p>Tropospheric ozone (O₃) pollution is a pressing concern in China’s Yangtze River Delta (YRD), yet its drivers remain insufficiently understood. We developed an integrated framework combining Positive Matrix Factorization (PMF) source apportionment, meteorological normalization, and explainable machine learning to investigate O₃ pollution during stagnant periods at a suburban site of YRD, focusing on high-O₃ months. O₃ concentrations frequently exceeded air quality standards, and O₃ formation exhibited a shift from annual volatile organic compounds (VOC)-limited to a warm-season transitional regime, indicating the need for coordinated VOCs and nitrogen oxides (NO_x) control during pollution periods. PMF resolved seven VOC sources, with mixed industrial emissions (MIE, 18.3%), biogenic emissions/biomass burning (BEBB, 24.3%), and industrial solvent use (ISU, 18.0%) as dominant contributors. Meteorological normalization showed that emission-driven O₃ (O₃_EMI) was consistently and substantially positive, whereas meteorology-driven O₃ (O₃_MET) was predominantly negative, underscoring the dominant role of local emissions and net O₃-scavenging effect of meteorology. SHapley Additive exPlanations (SHAP) analysis identified MIE, BEBB, and nitrogen monoxide (NO) as the top three drivers of O₃_EMI, with industrial MIE exhibiting the strongest positive contribution, likely due to its high loadings of reactive aromatics and oxygenated VOCs. Industrial VOC emissions thus emerge as the primary controllable driver of O₃ pollution under stagnant conditions. For O₃_MET, relative humidity and boundary layer height were the most influential factors. By focusing on O₃_EMI and leveraging PMF-resolved source factors, this framework enables targeted identification of controllable precursors, offering a transferable paradigm for diagnosing O₃ drivers in other regions facing similar challenges.</p></div>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"83 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ambient PM2.5 chemical composition in a residential area in Johannesburg, South Africa","authors":"Victoria Sekiti,&nbsp;Peter Molnár,&nbsp;Johan Boman,&nbsp;Janine Wichmann","doi":"10.1007/s10874-026-09495-8","DOIUrl":"10.1007/s10874-026-09495-8","url":null,"abstract":"<div><p>PM_2.5 is associated with multiple adverse health outcomes, yet data on its concentration, composition and sources in African cities remain limited. This study presents the first detailed characterisation of outdoor PM_2.5 in Johannesburg, South Africa. Twenty-four-hour filter samples were collected every sixth day from 3 October 2020 to 12 October 2021 at a residential site in the suburb of Buccleuch. Samples were analysed using gravimetric methods, smoke-stain reflectometry, optical transmissometry and X-ray fluorescence. Source contributions were assessed using principal component analysis (PCA), enrichment factor (EF) analysis and Hybrid Single Particle Lagrangian Integrated Trajectory model for backward trajectories. The mean PM_2.5 concentration was 8.1 µg.m⁻³(range: 0.04–30 µg.m⁻³), exceeding the World Health Organization (WHO) annual guideline (5 µg.m⁻³). Daily concentrations surpassed the WHO daily guideline (15 µg.m⁻³) on seven of the 55 sampling days. Mean black carbon (BC) and organic carbon (OC) concentrations were 0.51 and 0.46 µg.m⁻³, respectively. Twelve trace elements were detected, with Fe, K, S and Si most abundant. PM_2.5, BC, OC and several elements were significantly higher in winter and autumn, reflecting increased combustion activities and unfavourable meteorological conditions. Trajectory analysis indicated contributions from regional mining and coal-related activities. Integrated PCA and EF results showed that PM_2.5 comprised resuspended dust, traffic-related non-exhaust emissions, local residential combustion and regionally transported pollution. These findings highlight multi-source exposure and the need for coordinated air quality management at municipal and regional scales.</p></div>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"83 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10874-026-09495-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148281816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AHP-Weighted multi-pollutant composite with Getis–Ord Gi* hotspot analysis from sentinel-5P over Rajasthan, India","authors":"Saurabh Singh,&nbsp;Wafa Saleh Alkhuraiji,&nbsp;Rabin Chakrabortty,&nbsp;Arkadeep Dutta,&nbsp;Ali Raza,&nbsp;Mohamed Zhran","doi":"10.1007/s10874-026-09496-7","DOIUrl":"10.1007/s10874-026-09496-7","url":null,"abstract":"<div><p>Satellite data from the Sentinel-5P/TROPOMI sensor are used to monitor major air pollutants across Rajasthan in a consistent way. This study uses these observations to examine trends in six pollutants (NO₂, SO₂, CO, O₃, CH₄ and HCHO) from 2018 to 2024 and to find statistically significant hotspot areas. An Analytic Hierarchy Process (AHP) is applied to assign weights to the six pollutants after checking that the consistency ratio is within the accepted limit (CR ≤ 0.10). The weighted layers are combined to create a Composite Burden (CB) map. Hot and cold spots are then detected using the Getis–Ord Gi* statistic, based on a regular grid, an optimized neighborhood distance, row-standardized spatial weights, and false-discovery-rate correction. The state-level trend analysis shows that ozone (O₃) and methane (CH₄) are increasing steadily and significantly during the study period. Sulfur dioxide (SO₂) shows a small decline, while nitrogen dioxide (NO₂), carbon monoxide (CO) and formaldehyde (HCHO) show only small or non-significant changes. The CB and Gi* results highlight three main hotspot belts. The first is in the northern canal region, including Sri Ganganagar, Hanumangarh and Churu. The second follows the north-eastern industrial and transport corridor from Khairthal–Tijara through Bhiwadi, Neemrana, Kotputli, Behror, Alwar, Bharatpur and Dholpur. The third lies in the south-central and south-eastern industrial belt around Chittorgarh and the Kota–Baran–Jhalawar region, where many power plants and cement units are located. District-level analysis also shows similar increases in O₃ and CH₄ across major urban and industrial centres. This combined AHP and Gi* approach gives a clear, decision-oriented picture of Rajasthan’s multi-pollutant burden and points to priority regions for actions such as NOₓ/VOC control, SO₂ reduction at large point sources, and CH₄ management in agricultural and waste-rich districts.</p></div>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"83 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148261817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Particulate mercury in a suburb of the Yangtze River Delta, China: Characteristics, sources and health risk assessment","authors":"Dipesh Rupakheti,&nbsp;Xingna Yu,&nbsp;Xiufeng Yin,&nbsp;Junming Guo,&nbsp;Jiaying Zhang,&nbsp;Maheswar Rupakheti,&nbsp;Jianlin Hu","doi":"10.1007/s10874-026-09494-9","DOIUrl":"10.1007/s10874-026-09494-9","url":null,"abstract":"<div><p>This study investigates the characteristics, sources, and health risks of particulate-bound mercury (PBM) in PM₂.₅ from a suburban site in Nanjing, within the Yangtze River Delta, China. Seasonal sampling conducted in 2019 revealed a mean PBM concentration of 106 ± 115 pg/m³, with the highest levels in autumn. The PBM/PM₂.₅ ratio indicated significant anthropogenic influence. The estimated annual dry deposition flux of PBM was 39.86 µg/m²/yr. Health risk assessment determined that the non-carcinogenic risks from PBM exposure were below the safety threshold (Hazard Index &lt; 1) for both children and adults. However, children were found to be more vulnerable, with risk levels approximately 11 times higher than adults, primarily through the ingestion pathway. Back-trajectory analysis indicated that air masses influencing the site originated from local, regional, and long-range sources. The findings underscore that while current PBM levels pose minimal immediate health risks, the heightened susceptibility of children and the significant dry deposition flux warrant continued monitoring and further investigation into the complete atmospheric mercury cycle in this economically vital region.</p></div>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"83 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148172639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interplay of chemistry, meteorology, and transport in modulating Surface ozone over a tropical coastal semi-urban site in Southern India","authors":"Revathy S. Ajayakumar,&nbsp;Sobhan Kumar Kompalli,&nbsp;M. Ashok Williams,&nbsp;T. V. Lakshmi Kumar,&nbsp;S. Suresh Babu","doi":"10.1007/s10874-026-09493-w","DOIUrl":"10.1007/s10874-026-09493-w","url":null,"abstract":"<div>\u0000 \u0000 <p>Tropospheric ozone (O₃) pollution in urban regions has fueled numerous studies due to its far-reaching impacts on health, agriculture, and the climate. In this study, the variability of surface O₃ and the roles of distinct physical and chemical drivers were investigated at a tropical coastal semi-urban site in southern peninsular India using observations collected from February 2021 to February 2023. The results revealed higher mean O₃ concentrations during premonsoon due to stronger photochemistry. The lower seasonal amplitude (24%) of O₃ compared to other coastal/urban Indian locations suggests a strong reservoir of O₃ throughout the year at this tropical site. Furthermore, the influence of atmospheric chemistry on O₃ variations is examined using photolytic rate constants for NO₂ to estimate the Leighton ratio (Φ) (the ratio of O₃-production to O₃-loss rate) and the period of its deviation from unity. The overall Φ ranged from 0.5 to 1.9, and the average net production of O₃ was ~ 13.8 ± 5.2 ppbv h^− 1. The short-scale changes in O₃ and NO_x concentrations were governed by the mesoscale sea-land breeze circulation. The role of chemical, meteorological processes, and transport pathways in controlling surface O₃ concentrations was further demonstrated by evaluating three distinct high O₃ events. The Copernicus Atmosphere Monitoring Service model successfully reproduced the observed O₃ variability; however, absolute O₃ concentrations were typically overestimated, suggesting issues with the modeled processes and/or emission inventories.</p>\u0000 </div>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"83 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147559826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From clean air to severe haze: evolution of PM₂.₅ and water-soluble ions during a firework-influenced pollution episode","authors":"Zhendong Ke,&nbsp;Peipei Shao,&nbsp;Changlin Zhan,&nbsp;Chong Wei,&nbsp;Ziguo Liu,&nbsp;Ting Liu,&nbsp;Shan Liu","doi":"10.1007/s10874-026-09492-x","DOIUrl":"10.1007/s10874-026-09492-x","url":null,"abstract":"<div>\u0000 \u0000 <p>A severe air pollution episode occurred in Huangshi City, central China, during February 2024, coinciding with intensive Spring Festival fireworks. To investigate the chemical processes, PM₂.₅ mass and water-soluble inorganic ions (WSIIs) were analyzed in conjunction with ionic balance, correlation, and backward trajectory models. The episode exhibited three distinct phases. In the pre-pollution stage (February 5–8), PM₂.₅ remained stable around 60 µg/m³, with secondary inorganic aerosols (NO₃⁻, SO₄²⁻, NH₄⁺) as the major components under humid and stagnant conditions conducive to secondary aerosol formation. During the pollution peak (February 9–10), concentrations approached 800 µg/m³ due to firework emissions and stagnant conditions. Ion composition shifted markedly, with sharp increases in K⁺, Cl⁻, and Mg²⁺, concurrent decreases in NO₃⁻ and NH₄⁺, and a low neutralization ratio, indicating strongly acidic aerosols dominated by fireworks-derived sulfate. Ozone depletion further suppressed photochemistry and secondary aerosol production. In the post-pollution stage (February 11–14), improved dispersion and reduced emissions lowered PM₂.₅ to background levels, while NO₃⁻ and NH₄⁺ rebounded and dust-related ions (Ca²⁺, Mg²⁺) increased. Backward trajectory clustering revealed that northern transport contributed during the clean phase, local stagnation dominated the pollution peak, and mixed inflows supported atmospheric cleansing thereafter. These findings demonstrate that episodic fireworks can significantly reshape aerosol composition and acidity, with meteorological conditions determining the severity of pollution episodes.</p>\u0000 </div>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"83 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147441049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbonaceous composition assessment of PM2.5 near Taj Mahal in wintertime and heritage risk","authors":"Bhupendra Swarup Sharma,&nbsp;Astha Tomar,&nbsp;Sudhir Kumar Sharma","doi":"10.1007/s10874-026-09491-y","DOIUrl":"10.1007/s10874-026-09491-y","url":null,"abstract":"<div>\u0000 \u0000 <p>Carbonaceous components, including organic carbon (OC) and elemental carbon (EC), are critical constituents of Fine Particulate Matter (PM_2.5) as these components can significantly impact the local environment, climate, and human health. The present study aims to measure PM_2.5 and its carbonaceous content (OC and EC) in close proximity to the Taj Mahal during the winter period of January to February 2022. The estimated average mass concentration of PM_2.5 was 154.2 ± 65.4 µg/m³. This level is alarmingly high, being almost 2.5 times greater than the daily standard (60.0 µg/m³) set by the National Ambient Air Quality Standards (NAAQS) of India and a staggering 10 times higher than the World Health Organization (WHO) guidelines (15.0 µg/m³). Such elevated levels of PM_2.5 indicate severely degraded air quality in the area, posing significant risks to both the environment and human health. The concentrations of OC and EC were found to be 19.8 ± 7.8 µg/m³ and 8.11 ± 2.81 µg/m³, respectively. These value underscore the predominance of carbonaceous aerosols in the local atmosphere. OC and EC are found to be positively corelated with each other indicating their emission from similar sources. The eight carbon fraction analysis of PM_2.5 shows that biomass burning and road dust were the main sources of emission at sampling site. The average concentration of primary organic carbon (POC) was 14.67 µg/m³ whereas secondary organic carbon (SOC) was recorded as 5.55 µg/m³, highlighting that organic carbon in the region is contributed by both primary sources and secondary processes, including the condensation or adsorption of organic compounds.</p>\u0000 </div>","PeriodicalId":611,"journal":{"name":"Journal of Atmospheric Chemistry","volume":"83 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147335722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}