Air Quality Atmosphere and Health最新文献

Accurate exposure assessment is essential for understanding environmental health risks and for informing effective policy measures, particularly in areas where urban and industrial sources coexist. This study assessed long-term (2006–2019) air pollution exposure in the orographically complex Venafro Valley (southern Italy), an area characterized by multiple emission sources, to support an epidemiological investigation. To capture the spatial and source-specific heterogeneity of emissions, two complementary approaches, generally used independently, were combined. Diffuse pollution was characterized using fine particulate matter (PM_2.5) estimates derived from a satellite-based random forest model, while industrial contributions were evaluated through nitrogen oxides (NO_x) concentrations simulated by the Wrf/Calmet/Calpuff dispersion modelling system. Four exposure classes were defined for each pollutant using the “natural breaks” method to highlight relative spatial gradients rather than absolute concentration levels. The two methods revealed distinct exposure patterns. PM_2.5 peaked at the center of the valley, in the urban area of Venafro, largely influenced by traffic and biomass heating, whereas NOₓ hotspots were located near the industrial plants situated at the valley edges, close to the surrounding mountains. Overall, the findings highlight the need for integrated, multi-source approaches and additional monitoring stations to prevent biased exposure assessments. Although this study focuses on a specific area, the methodologies applied here may be transferable to other environmental or epidemiological contexts.

This study was conducted during high-pollution days, designated as Event I (PM_2.5: ≥ 300 µg m⁻³), and during moderate-pollution days (Events II; PM_2.5: ≤ 100 µg m⁻³) to understand the dynamic and toxic nature of submicron (PM₁) and fine particles (PM_2.5). Average PM₁ and PM_2.5 concentrations were 259.50 μg m⁻³ and 307.20 μg m⁻³, respectively, for Event I. These values declined to 69.25 μg m⁻³ and 103.58 μg m⁻³ during Event II for PM₁ and PM_2.5, respectively. This reduction in PM concentration was attributed to a significant decrease in the primary source emissions, regional weather variability and atmospheric chemical processes. Chemical composition such organic carbon (OC) and elemental carbon (EC), inorganic species (SO₄²⁻, NO₃⁻, NH₄⁺, Cl⁻) were observed higher in Event I compared to Event II. The secondary organic carbon (SOC) fraction was elevated during Event I in PM_2.5, accompanied by higher organic pollutants, which are attributed to enhanced primary emissions. Morphological analysis revealed diverse particle shapes, including irregular, fibrous, rod-like, elongated, spherical, and flattened forms, characterized by variations in aspect ratio, roundness, form factor, and circularity. Based on morphology and elemental mapping, we observed carbonates, quartz, sulfates, metal oxides, and fluoride particles. Furthermore, sulfate compounds appeared as K-S–O (high density) in Event I and as Na-S–O (mirabilite, low density) in Event II. The oxidative potential (OPv and OPm) showed higher levels in Event I. However, OPm exhibited a slightly increase in PM_2.5 during Event II also, due to the change in particle characteristics during atmospheric chemical processes. The total excess cancer risks (ECRs) were higher (PM₁:1.18 × 10^–3 and PM_2.5: 8.48 × 10^–4) for Event I and exhibited lower ECRs (PM₁: 8.98 × 10^–4 and PM_2.5: 3.46 × 10^–4) for Event II. Among trace metals, Chromium (Cr), Nickel (Ni), and Cobalt (Co) exhibited elevated ECR, while Lead (Pb) and Cadmium (Cd) exhibited lower ECR. Inhalation exposure was also higher during Event I compared to Event II; however, OPm contributed significantly exposure to both Events.

New Delhi, the capital city of India, routinely records hazardous fine-particle concentrations during the post-monsoon season, yet the quantitative link between regional crop-residue burning and episodic haze remains contested. This study integrates multi-sensor satellite products with atmospheric trajectory modelling to attribute the late-October–early-November aerosol enhancement over the capital during 2020–2024. Columnar aerosol optical depth (AOD) at 550 nm was extracted from MODIS Terra–Aqua (10 km); active-fire detections were taken from VIIRS S-NPP (375 m); harvest dynamics were approximated from MODIS NDVI (250 m); and 120 h forward air-mass trajectories at 500–1000 m a.g.l. were generated with NOAA-HYSPLIT driven by GDAS 1° fields. Seasonal-trend decomposition and Theil–Sen statistics revealed a consistent AOD surge of 0.35 ± 0.06 above pre-monsoon levels (p < 0.05). Punjab contributed 90% of regional fire counts in 2020 but only 40% in 2024, whereas Haryana showed a marginal decline. Daily fire counts within Punjab–Haryana explained 78% of Delhi AOD variance during October–November (r = 0.78, p ≪ 0.01). NDVI differencing confirmed harvest-related vegetation loss across > 90% of cropland pixels in week 43 each year. Cluster analysis indicated that 60% of trajectories originating overactive-burn zones intersected Delhi within 36 h, increasing the probability of AOD > 1.2 by a factor of five. These convergent lines of evidence identify stubble combustion as the primary driver of Delhi’s recurring autumn haze. Accelerated deployment of in-situ straw incorporation, baler-mulcher systems, and regional burning-ban enforcement, supported by real-time satellite surveillance, is recommended to achieve National Clean Air Programme particulate-matter targets and to safeguard regional public health. Economic co-benefits are anticipated through fuel savings, improved soil organic carbon, and rural air-quality gains across the Indo-Gangetic Plain.

Air pollution is a widespread global environmental hazard that poses significant threats to both human health and the earth’s ecosystems. Particulate matter (PM_2.5) is one of the most perilous forms of air pollution if present in higher concentrations. This tiny material is incorporated into the air by both anthropogenic and natural activities and may further lead to poor ambient air quality. The size of these particles has been directly linked to their reactivity and potential impact on human health. Inhalable coarse particles 2.5 to 10 μm in diameter and fine particles < 2.5 μm in diameter are the primary concern due to their high surface-to-volume ratio. Owing to their diverse physicochemical characteristics, such as the heterogeneous mixture of particle sizes, small diameters, and chemical components, PM_2.5 have been found to be associated with many respiratory and reproductive-related disorders, cardiovascular diseases, central nervous system dysfunctions, and cancer. In this review article, we have highlighted the sources, occurrence, and human toxicological effects of PM_2.5, as well as their role in the progression of various human diseases. Various preclinical and epidemiological studies are also covered to reveal the harmful effects of PM_2.5 on human health worldwide. This comprehensive analysis of PM_2.5 may help policymakers and other stakeholders adopt more stringent measures to phase out PM_2.5 levels and mitigate its negative impacts on human health and the ecosystem.

Carbon mitigation policies have emerged as a pivotal strategy for mitigating global climate warming, making it imperative to accurately evaluate the effectiveness of such policies. This study employs a textual analysis approach to construct an indicator of carbon policy intensity (CPI) at the municipal level in China, and utilizes unbalanced panel data from 2006 to 2021 to examine its impact on carbon emissions (CE) in China. The findings reveal as follows: (1) CPI exerts a significant positive effect on reducing carbon emissions, a conclusion that remains robust after being validated by a series of robustness strategies, including multi-time-point difference-in-differences. (2) CPI primarily facilitates carbon emission reduction by stimulating green innovation and promoting the upgrading of industrial structures. (3) CPI demonstrates a more pronounced effect on emission reduction in eastern regions and areas with lower levels of carbon emissions, while its effect is relatively weaker in central and western regions and areas with higher levels of carbon emissions. The research not only confirms China’s positive efforts in carbon mitigation policies but also underscores the necessity of formulating regionally targeted, differentiated carbon policies.

Indoor air pollution is a significant concern as people spend more than 90% of their time indoors, and exposure to indoor air pollutants has been linked to various health issues. Microorganisms play a crucial role in the production of indoor air pollutants, including the release of volatile organic compounds (VOCs) through their metabolic processes and the degradation of primary air pollutants, resulting in the formation of secondary air pollutants. Given the growing evidence linking respiratory diseases to microbial exposure and moisture-damaged buildings, further investigation into microbial volatile organic compounds (MVOCs) as secondary-level indoor air pollutants is warranted. Using a scoping review methodology, this paper examined the existing literature published between 2010 and 2023 that focuses on MVOCs in indoor air in homes and schools. This review identifies information gaps and trends in the scoped literature, synthesizes and consolidates available information, describes, characterizes, and consolidates information on the sources, concentrations, range, and trends of MVOCs, associated health risks, economic and socioeconomic factors, and pinpoints areas that require further investigation. Gaps and limitations identified in the current understanding of MVOCs in indoor air include limited generalizability of findings, incomplete assessment of MVOCs, inadequate consideration of confounding factors, and a lack of standards and exposure thresholds. Identified gaps provided an opportunity to present recommendations for the investigation into MVOCs in indoor air, including the need for investigation into specific cause and effect relationship investigation, remediation strategy, interactive and combined effects, and permissible exposure limits.

Road dust constitutes a significant source of atmospheric particulate matter (PM), substantially contributing to urban pollution loads. However, systematic source apportionment of road dust remains insufficient, and conventional receptor modeling approaches exhibit notable limitations. This study aims to trace the sources of urban road dust by integrating micro- and macro-scale perspectives. We innovatively developed and applied a methodology that leverages Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS) characterization of particle heterogeneity and regional disparity to constrain Positive Matrix Factorization (PMF) source apportionment. Key findings reveal that: The principal sources of urban road dust were identified as geogenic sources, sea salt, coal combustion, vehicle emissions (further differentiated into exhaust and non-exhaust mechanical wear when the PMF model featured multiple characteristic factors), and industrial activities. The proposed multi-scale integrated approach enables more scientifically robust and precise identification of PM sources, offering a novel methodological framework and valuable reference for researchers in related fields.

Molecular passage across the placenta generally serves developmental purposes, but some also can induce harm. Particulate matter (PM) affects the pregnancy through the maternal circulation to the placenta. Black Carbon (BC) particles, produced by high temperature fuel combustion, contribute to global air pollution and climate change. Its health impacts likely extend beyond respiratory complications. Thus, studying BC translocation into human tissues provides insights into the mechanisms of observed adverse outcomes. The placenta is a useful organ since it provides further understanding of placental transport mechanisms, impacts on the tissue and embryo/fetus, and for developing prevention strategies. Having well-measured tissue dose metrics would also provide an epidemiological tool to related exposures to a variety of health outcomes in the woman, fetus, and resulting child. Thus, quantitatively establishing their presence in the placenta and blood provides an important exploratory tool. Such submicron particles challenge traditional microscopy limits, requiring effective measurement systems and rigorous assessment strategies. A microscopic methodology for quantifying BC particles in human placental histology slides utilizing multiphoton microscopy has been previously reported. However, there are substantial issues with the prior method and thus, this work has developed a more rigorous approach to demonstrate transplacental movement of BC particles.

Tropospheric ozone (O₃) remains a critical air quality challenge in China despite effective reductions in PM_2.5 levels. This study investigates the phenomenon of Ozone Suppression (OS) under high-temperature conditions across six major urban agglomerations in China—Beijing-Tianjin-Hebei (BTH), Yangtze River Delta (YRD), Pearl River Delta (PRD), Cheng-Yu (CY), Middle Yangtze River Delta (MYR), and Middle Plain (MP)—from 2015 to 2024. Using a Z-test, we identified the cutoff temperature (T_c) for OS events and analyzed its spatiotemporal variability. Results revealed significant regional differences, with T_c ranging from 28.0 °C to 35.3 °C, higher in plains and lower in coastal and plateau regions. An XGBoost model was developed to predict daily maximum 8-hour O₃ (O₃-8 h) under OS, demonstrating strong performance (CV-R²: 0.69–0.85, CV-RMSE: 18.12–23.37 µg·m^− 3). SHAP analysis quantified the relative contributions of meteorological, anthropogenic, and natural factors. Key drivers included PM_2.5, 2-m temperature (t2m), and meridional wind (v10), with pronounced regional heterogeneity: PM_2.5 dominated in MYR, PRD, and YRD, while t2m, surface solar downwards (ssrd), and 2-m dew point (d2m) were primary in BTH, CY, and MP, respectively. Meteorological factors contributed 39.0%–66.2% to O₃-8 h variations. These findings underscore the need for region-specific ozone control strategies tailored to localized drivers under warming climate conditions.

Magnetic nanoparticles are recognized components of air pollution with potential health impacts. While outdoor sources and effects have been studied, the characteristics, origins, and health implications of magnetic particles indoors remain less understood. Here we review current literature on indoor magnetic particles, analyzing their physicochemical properties, sources and potential health risks inferred from related environmental studies. Although source-attribution studies show progress for outdoor emissions, only limited evidence exists for indoor sources, with combustion activities, cigarette smoke, and toner-based printing identified as contributors. Current data indicate that exogenous magnetic nanoparticles can be internalized and translocated across multiple organs, and several toxicity pathways have been described. However, key uncertainties persist regarding dose–response relationships, toxicologically meaningful magnetic metrics, and exposure thresholds. These findings highlight the need for integrated research to better characterize indoor magnetic nanoparticles, differentiate indoor and outdoor sources, and clarify their role in chronic health outcomes associated with air pollution.