Search Results (6,159)

Although prior research focused on Baghdad has identified variability in fine particulate matter concentrations (PM_2.5) and their origins, there remains uncertainty in the identification of the relative importance of local and long-range PM_2.5 sources. This study analysed hourly air pollutant concentrations and meteorological data from three monitoring sites over the year 2019 in Baghdad, namely Al-Wazeriya (WZ), Al-Andalus Square (AS), and Al-Saiydiya (SA) sites, to determine the nature of PM_2.5 sources. Multi-stage statistical models were utilised to address inherent data limitations and varying sampling dates caused by limitations on power supplies to monitoring equipment, thus improving the identification of urban particulate sources. Bivariate polar plots, concentration ratios, and conditional bivariate probability function (CBPF) plots were used to identify local sources of PM_2.5. Potential Source Contribution Function (PSCF) and concentration weighted trajectory (CWT) methods were employed for distant and regional source apportionment. Domestic diesel generators are suggested to be the primary local source of PM_2.5 pollutants in Baghdad’s WZ area (categorised as residential with significant traffic volumes). Gasoline- and diesel-fueled motor vehicles significantly contribute to PM_2.5 concentrations in the AS and SA areas, which are commercial areas with the latter having close proximity to motorway sources. Additional impacts result from gas flaring and thermal power plants in these regions. Long-range PM_2.5 transport may be attributed to the combustion of low-quality heavy fuel oils from several potential sources, including Nahrawan brick factories, oil fields, and Al-Musayyab thermal power plants, primarily towards the northeast, east, and southeast of Baghdad. Transboundary contributions to PM_2.5 concentrations in Baghdad were also identified, from industrial sources in western Iran and eastern Syria, as well as dust particulates, and oil and gas production from southwestern Iran’s Khuzestan Province, Kuwait, and the Arabian Gulf. Low to medium wind speeds (1–4 ms⁻¹) were linked with the highest source contributions, suggesting local emission sources to be the most significant contributors to high PM_2.5 at the studied sample locations. Full article

Upper Northern Thailand continues to face a protracted structural crisis from fine-particulate matter (PM_2.5), primarily driven by biomass burning and wildfires. Conventional mechanical capture systems, such as cyclones, often suffer a drastic efficiency drop when treating sub-micron particles. This study introduces an innovative Evaporative Condensation Growth Scrubber (ECGS) designed to bridge this technological gap by promoting the growth of fine particles through heterogeneous nucleation. Experimental testing across 10 different nozzle configurations was conducted to optimize the system’s performance. The results revealed that the ECGS system significantly outperformed the dry cyclone (Baseline) across all nine testing configurations. While the Baseline showed inherent limitations in capturing sub-micron particles, the ECGS demonstrated relative efficiency improvements ranging from 39.53% to 83.23% for PM_2.5, and 26.10% to 61.50% for PM₁₀ compared to the baseline. Optimal performance was achieved using a 90-degree injection angle and a 10 cm distance, which created a complete spray curtain and maximized collision probability. Under these conditions, the outlet PM_2.5 concentration stabilized at 11.81 µg/m³ within 180 s of water injection. Crucially, despite sensor interference caused by high relative humidity, the system’s effectiveness was confirmed by a significant difference in performance in PM₁₀ and PM_2.5 removal. The PM₁₀ collection efficiency outperformed that of PM_2.5 by 28.82%, providing empirical evidence that PM_2.5 particles successfully acted as nuclei for condensation and grew into the larger PM₁₀ size range. This particle growth enabled more effective centrifugal separation, demonstrating that the ECGS system offers a viable and efficient solution for fine particle removal in highly polluted environments. Full article

Tree rings record environmental conditions and can serve as long-term biomonitors of urban pollution. This study evaluated the radial growth and chemical composition of Pinus greggii wood in three urban green areas of Mexico City: San Juan de Aragón Park (SJA), Sierra de Guadalupe State Park (GUAD), and Vivero Coyoacán National Park (COY). Tree ring chemical elements were analyzed at annual resolution for the period 2002 to 2022, and their relationships with atmospheric pollutant concentrations, including nitrogen oxides (NO_x), carbon monoxide (CO), ozone (O₃), and particulate matter (PM), of medium size or smaller than 10 µm, including the fractions PM_2.5 and PM₁₀, were assessed using a spatial scaling approach. Elemental concentrations were determined using X-ray fluorescence (XRF). Statistical analyses included analysis of variance (ANOVA), Theil–Sen trend estimation, and Pearson correlation with lag analysis (up to 3 years). The oldest trees were recorded in COY (52 years), while the youngest were recorded in GUAD (13 years). Distinct temporal patterns in elemental concentrations were detected among sites; for instance, peak concentrations of Fe (307 ppm), Cu (11 ppm), and Zn (51 ppm) occurred in GUAD in 2021, while Pb concentrations declined during 2019–2020 across all three sites. Significant correlations (p < 0.05) were identified between Cu, Fe, Zn, and Pb and the atmospheric pollutants (NO_x, PM_2.5, PM₁₀, O₃). Notably, O₃ showed significant positive correlations with Fe at SJA (up to r = 0.80) and GUAD (up to r = 0.46) with lags ranging from 0 to 3 years, suggesting delayed responses between atmospheric pollution and elemental deposition in tree rings. These findings highlight the sensitivity of P. greggii to urban atmospheric pollution and support its potential as a long-term biomonitoring tool, as well as its importance for informing policies aimed at improving air quality and promoting the sustainable management of urban green spaces. Full article

Nanoparticles (interchangeably called ultrafine particles) constitute one of the growing risks encountered in everyday life. Both short- and long-term exposure to them, as well as to particulate matter in general, may pose serious health risks. In this study, we focus on monitoring of particle concentration in urban air for 200 days, with special attention to nanoparticles. The overall data coverage exceeded 80%, reaching over 97% in three selected months. Measurements were carried out at 25.5 m height in southern Warsaw, in close vicinity to residential blocks with apartments also at the same level. Data were collected from January to first half of August 2025 using a Grimm MINI-WRAS portable wide-range aerosol spectrometer and a thermo-hygro-barometer. Over the 8-month period, significant variations between months and days in both nanoparticle and all particulate matter concentrations were observed. Winter months were almost four times more polluted with particles (both nanoparticles and those above 100 nm) than spring and summer periods. Although nanoparticle concentration in colder months was higher, the percentage of nanoparticles was lower. An important aspect of these investigations was comparing the obtained results with publicly available air pollution data from urban air quality monitoring stations, which represent ground-level measurements. At rooftop altitude, PM_2.5/PM₁₀ ratios were significantly higher than those measured at ground level. Full article

Fireworks are widely used at festive events worldwide and are commonly employed at indoor wedding ceremonies in Türkiye; however, their impact on indoor air quality has not been adequately investigated. This study examines particulate matter (PM) emissions generated by volcano-type fireworks used in indoor wedding halls. Particle samples were collected across five size fractions (>2.5, 1.0–2.5, 0.50–1.0, 0.25–0.50, and <0.25 µm) using a 5-stage Sioutas cascade impactor, and elemental compositions were determined by ICP-MS. PM_2.5 concentrations ranged between 1518 and 7796 µg/m³, while total PM concentrations varied between 2088 and 8656 µg/m³. These values are substantially higher than the guideline limits reported by the World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA), indicating very high short-term exposure levels. Fine particles (PM_2.5) accounted for 56.5–92.4% of total PM, with particles smaller than 1 µm forming the dominant fraction. Among the analyzed elements, aluminum (Al), zinc (Zn), and iron (Fe) were the most abundant metals, predominantly associated with fine particles. The highest concentrations were generally observed in the 0.25–0.5 µm size range. These findings showed that the use of indoor fireworks can lead to high concentrations of fine particulate matter and metal-rich aerosols. This issue should be considered, as it may pose a health risk for those in enclosed spaces in future studies. Full article

Most air pollution research in India has predominantly focused on the Indo-Gangetic Plain (IGP) owing to its high pollution levels and dense populations, leaving peninsular India comparatively undercharacterized. In contrast, South India remains underexplored because of its relatively limited long-term monitoring and more favorable meteorology. This geographical imbalance restricts a comprehensive national understanding of particulate matter (PM) dynamics. Addressing this gap, the present study delivers a multi-scale (hourly to interannual) spatiotemporal assessments of PM_2.5 across eight monitoring stations in Andhra Pradesh, a South Indian State, for the period 2020–2024. The analysis reveals pronounced seasonal variability, with persistent winter and post-monsoon maxima. Although overall concentrations are low compared to northern India, urban–industrial centers such as Visakhapatnam and Rajahmahendravaram frequently exceeded both the National Ambient Air Quality Standards (NAAQS) and World Health Organization (WHO) guidelines. Notably, Amaravati, a non-industrial and low-lying inland site, exhibited anomalously moderate PM_2.5 levels, with ~11.58% of hourly values surpassing 60 µg m⁻³. The COVID-19 lockdown period further offered a natural experiment, revealing substantial reductions (30–65%) in PM_2.5 and PM₁₀ at major urban sites while concurrent ozone enhancements (up to ~50%) at Tirupati and Rajahmundry exposed complex photochemical sensitivity under reduced NO_x conditions. Satellite-based MERRA-2 estimates corroborated inter-annual variability and the short-lived improvement in air quality. This study demonstrates that air quality dynamics in the state of Andhra Pradesh are governed by region-specific meteorological controls, episodic processes, and localized emission characteristics, necessitating expanded long-term monitoring infrastructure and improved satellite–ground calibration frameworks. Full article

This study investigates the geochemical behavior and transport mechanisms of Rare Earth Elements (REEs), Yttrium (Y), Zirconium (Zr), and Hafnium (Hf) in three natural water systems under reducing conditions: the Santa Barbara and Occhio dell’Abisso mud volcanoes and a sulphureous spring at Villafranca Sicula. A comprehensive fractionation approach was applied to isolate the truly dissolved fraction (TDF < 10 kDa), the colloidal fraction (10 kDa < CF < 450 nm), the suspended particulate matter (SPM > 450 nm), and the associated bottom sediments. Analytical results reveal that REE distribution is significantly influenced by redox conditions and solid–liquid interface processes. The absence of negative Cerium (Ce) anomalies and the presence of pronounced positive Europium (Eu) anomalies in the Santa Barbara and Occhio dell’Abisso waters suggest strongly reducing environments where Eu²⁺ stability is enhanced. Shale-normalized patterns indicate that, while SPM and sediment fractions often exhibit Middle REE (MREE) enrichment, linked to Mn-bearing and Fe-oxyhydroxide phases, the dissolved phase reflects dissolution processes governed by a non-CHARAC (CHarge-and-RAdius-Controlled) behavior. Furthermore, the study highlights a significant decoupling in the Zr/Hf and Y/Ho pairs. While these pairs remain coherent during magmatic processes, they undergo mutual fractionation in aqueous systems due to differential reactivity toward colloidal surfaces and organic ligands. Specifically, Zr/Hf ratios in the colloidal and dissolved fractions deviate from chondritic values, driven by the preferential scavenging of Hf onto mineral surfaces. These findings underscore the utility of REE and Zr-Hf systematics as high-resolution tracers for reconstructing water–rock interaction processes and elemental cycling in complex hydrological environments. Full article

Glacial ice cores are evidence of past environmental conditions through gases and particulate matter trapped within the drilled material. The Central Andes in the South American region are highly sensitive to climate changes; a long record of temperature and precipitation variability can be found in relation to massive ice caps. Available oxygen isotope data from three glacial ice cores from Nevados Sajama, Huascaran and Illimani (Peru and Bolivia) drilled over the last decades in the Central Andes are revisited to investigate climate variability over the past seven millennia, a period characterized globally by remarkable climatic stability. The analysis revealed statistically significant millennial- and centennial-scale periodicities in the isotope records ranging from centennial to millennial timescales. These cycles have periods of 1.3, 0.87, 0.67, 0.46, and 0.25 kiloyears (ka). A series of regional temperature minima and maxima are also identified. This variability in the Andean climate during the mid and late Holocene is interpreted as being strongly controlled by changes in solar activity, in particular, the forcing of “grand solar minima” is recognized. Likewise, less frequent climate changes could be correlated with Bond cycles and increased or decreased activity of the Atlantic Meridional Overturning Circulation (also known as AMOC or the thermohaline), among other climate forcings such as volcanic activity. Full article

Accurate, high-resolution emission inventories are essential for air quality modeling and policy evaluation, yet national-scale inventories for Thailand remain limited in spatial and temporal detail. This study develops a comprehensive national emission inventory for Thailand in 2019 (EI–TH 2019), covering 12 major air pollutants and greenhouse gases across key sectors, including energy, transport, industry, agriculture, waste, and residential activities. The inventory is constructed using country-specific activity data from official statistics and sectoral surveys, combined with GAINS-consistent emission factors and control assumptions. Emissions are resolved at 1 × 1 km spatial resolution and monthly temporal resolution to capture Thailand-specific emission dynamics. The results show that emissions across major pollutants are dominated by a limited number of source groups, with biomass burning and residential solid-fuel use driving particulate matter, transport dominating NO_x and CO emissions, large-scale combustion and industry controlling SO₂ emissions, and agriculture contributing the majority of NH₃ emissions. Strong seasonal variability is observed in PM_2.5, CO, and NH₃, primarily driven by dry-season biomass burning, whereas NO_x and SO₂ exhibit relatively stable temporal patterns. The reliability of EI–TH 2019 is supported by a multi-dimensional evaluation framework. Temporal consistency is demonstrated through strong agreement between modeled PM_2.5 emissions and ground-based observations, as well as between NO_x emissions and satellite-derived TROPOMI NO₂ (r = 0.93; ρ = 0.96). Biomass burning timing is further validated using satellite fire activity (VIIRS), showing consistent seasonal patterns. Comparisons with global inventories (EDGAR v8.1, HTAP v3.2, and GFED5.1) reveal systematic differences in sectoral contributions, temporal profiles, and emission magnitudes, particularly for biomass burning, reflecting the importance of country-specific data and assumptions. Overall, EI–TH 2019 provides a robust, high-resolution, and policy-relevant emission dataset that improves the representation of emission processes in Thailand. The results highlight key priority sectors—biomass burning, transport, industry, and agriculture—for targeted emission-reduction strategies and support applications in chemical transport modeling, exposure assessment, and integrated air-quality and climate-policy analysis. Full article

Kuwait experiences persistently high levels of air pollution driven by industrial emissions, transportation, oil-related activities, and frequent desert dust storms. This study aims to synthesize and critically evaluate the available evidence on the relationship between air pollution, Air Quality Index (AQI), and health outcomes in Kuwait using a guided narrative review approach. A guided literature search identified 26 peer-reviewed studies published between 2014 and 2026 about Kuwait air pollution, which were assessed for methodological characteristics, pollutant types, health outcome categories, and vulnerable populations. The most frequently examined pollutants were particulate matter (PM_2.5: 69%; PM₁₀: 38%), followed by NO₂ (23%), multi-pollutant and AQI-based (19%), O₃ (12%), SO₂ (12%), VOCs and PAHs (8%). Health-related investigations most commonly addressed mortality and respiratory morbidity, while cardiovascular, metabolic, biomarker-based, and cancer-related outcomes were less frequently represented. Among studies reporting direct health outcomes, elevated PM_2.5 exposure was generally associated with increased risks of respiratory hospitalizations, cardiovascular events, and all-cause mortality. Susceptible populations identified across the literature include children, older adults, individuals with pre-existing chronic conditions, and outdoor workers, who may experience higher exposure levels and greater health vulnerability. However, a substantial proportion of the included studies focused primarily on exposure characterization or pollutant modeling without direct assessment of health outcomes. These studies nonetheless indicate consistently elevated pollutant levels and seasonal variability, which may plausibly contribute to population health risks. Overall, while the available Kuwait-specific evidence suggests potential adverse health effects linked to air pollution, the strength of direct epidemiological evidence remains limited. Important gaps persist, including the scarcity of long-term cohort studies, limited multi-pollutant analyses, and insufficient integration of AQI categories with health outcomes. These limitations highlight the need for more robust and longitudinal research to better quantify health risks and inform public health policy in Kuwait. Full article

This study presents an optimized numerical and empirical modeling framework for ionic wind-driven electrostatic precipitators designed for atmospheric particulate matter (PM) removal. While traditional particle tracing models in long ducts often suffer from transient evaluation errors (the “flight time paradox”), this work introduces a Fate-based Steady-state Evaluation (FSE) method. By coupling Electrostatics, Laminar Flow, and Particle Tracing in a high-fidelity 2D axisymmetric model, we achieved a baseline validation with a Mean Absolute Error (MAE) of 5.3% compared to experimental data (20 kV, 0.5 m/s). Furthermore, a non-linear regression engine based on a physical-exponential decay function was developed to provide real-time performance predictions. The resulting hybrid model demonstrates a high scientific reliability (R² = 0.98), establishing it as a robust tool for the design and optimization of air purification systems targeting fine atmospheric aerosols (0.1–3.0 μm). In addition, the proposed Fate-based Steady-state Evaluation (FSE) method eliminates transient bias commonly observed in long-duct Lagrangian particle simulations. This methodological improvement enables statistically consistent efficiency estimation for electrohydrodynamic filtration systems and can be applied to a broad class of Computational Fluid Dynamics (CFD)-based particulate capture studies. The developed framework enables rapid design optimization of compact electrohydrodynamic filtration systems and provides a practical alternative to computationally expensive full-scale Computational Fluid Dynamics (CFD) simulations. Full article

Environmental factors play a crucial role in shaping human development. This study explores an extension of the United Nations Planetary pressure-adjusted Human Development Index ($PHDI$) by incorporating three methodological refinements: (i) a disaggregated analysis of material footprint data; (ii) the inclusion of a local adjustment factor related to fine particulate matter (PM${}_{2.5}$) exposure; and (iii) a variation to the planetary pressure aggregation method for obtaining the $PHD{I}^{*}$ index. The geographical scope encompasses 137 countries across the five permanently inhabited continents (Africa, America, Asia, Europe, and Oceania). The analysis first evaluates how these additional parameters deviate from the standard UN framework, followed by a continental assessment of national performances and their underlying drivers. A revised global ranking is presented, with countries categorised into four development levels based on Jenks Natural Breaks-derived cut-off values. Comparative cartographic visualisations highlight the shifts among the standard indexes and the proposed $PHD{I}^{*}$, illustrating that while some high-development countries—primarily in Europe—maintain their status, the inclusion of environmental aspects change the categories of important countries. These results suggest that accounting for localised environmental stressors and a more detailed material footprint analysis provides a more granular representation of the constraints on human development. Full article

The aim of this paper is to identify the major environmental impact categories associated with geotechnical works, evaluate the adequacy of commonly used weighting methods, and highlight the need to adapt them to sector-specific characteristics and local conditions. Currently applied weighting approaches rely on standardized values that may not accurately reflect the environmental impact of activities across different economic sectors. Moreover, several impact categories, such as eutrophication, acidification, and water use, are strongly dependent on local conditions. The study included the identification of key environmental challenges across Europe and the development of maps illustrating their spatial distribution. Four weighting methods were applied and compared in terms of their influence on the ranking of assessed materials. The analysis shows that geotechnical works include Global Warming Potential, Photochemical Ozone Creation Potential, Particulate Matter, and Abiotic Depletion Potential—fossil. Adapting weightings to local conditions did not change the ranking of analyzed materials in Poland. However, it may significantly influence the results in regions facing different environmental challenges. The results may support the adaptation of environmental assessment methods in geotechnics and contribute to informed decision-making for sustainable development. Full article

Particulate matter is a significant component of air pollutants, especially PM_2.5-bound polycyclic aromatic hydrocarbons (PAHs), due to multiple toxicological effects on organisms. In this study, the concentrations of PM_2.5-bound PAHs at the two most important ports in Mexico (Veracruz and Manzanillo) were determined to identify emission sources and evaluate potential health impacts. Average PM_2.5 concentrations were higher in Veracruz (12.90 ± 4.77 μg/m³) than in Manzanillo (10.96 ± 3.99 μg/m³), although both were below Mexico’s current air quality standards. Total PAH concentrations were also higher in Veracruz (22.14 ± 16.76 ng/m³) compared to Manzanillo (11.65 ± 9.04 ng/m³). The identified PAHs and diagnostic ratios indicated different emissions patterns: in Manzanillo, concentrations were associated with high-temperature pyrogenic sources, while in Veracruz, greater contributions from mixed sources were observed. The ILCR assessment was 4.61 × 10⁻⁷ for Manzanillo and 8.77 × 10⁻⁷ for Veracruz, both below the accepted risk threshold. Despite relatively low health risk estimates, the presence of carcinogenic PAHs, such as benzo[a]pyrene, highlights the need for continuous monitoring and mitigation strategies in port environments. These results provide pioneering, highly valuable insights into the dynamics of air pollution in these Mexican ports and their potential health implications. Full article

The identification and characterization of air pollutants in metropolitan environments are of paramount global concern due to their significant implications for air quality and public health. This study investigates the chemical composition of fine particulate matter (PM_2.5) at two strategically selected urban sites in Seoul, South Korea, during 2020: Gwanghwamun Plaza, representing a high-density central location, and Bokjeong Station, situated in the metropolitan periphery. A key aspect of this research is the detection of terephthalic acid (TPA)—a distinct marker of polyethylene terephthalate (PET) combustion—using high-resolution liquid chromatography–time-of-flight tandem mass spectrometry (LC-ToF-MS/MS). Results from the simultaneous measurement campaign demonstrate that nighttime conditions strongly influence PM_2.5 at both sites, with increases observed not only in absolute concentrations (levoglucosan, TPA, As, CO, and NH₃) but also in OC-normalized ratios (levoglucosan/OC and TPA/OC). The consistent nighttime enhancement of these ratios suggests that the observed increases cannot be explained solely by reduced planetary boundary layer height but instead indicate relatively stronger emission contributions. These increases are likely influenced by waste incineration activities, wherein PET-based plastics and wood materials are combusted. Furthermore, assessment of the dithiothreitol assay-derived oxidative potential (DTT-OP) underscores the heightened oxidative stress associated with these emissions, posing substantial health risks. Full article