Search Results (3,482)

Gas flaring from upstream oil and gas production remains a significant source of air pollution and toxic emissions, with major implications for human health and climate. However, the number of people living near flaring has not been quantified globally. This study presents the first worldwide, settlement-scale assessment of populations living within 1 km and 3 km of active upstream flare sites between 2016 and 2023, with projections to 2030. Using the VIIRS Nightfire satellite product, which provides global detections of high-temperature combustion sources, and the Global Human Settlement Layer (GHSL) population and settlement data, we developed a transparent and reproducible geospatial workflow to compute proximity-based exposure indicators by buffering flare locations and intersecting them with population rasters The analysis provides consistent estimates across five settlement categories: rural, peri-urban/suburban, semi-dense urban, dense urban, and urban centres. The VIIRS-based flaring time series combined with GHSL projections allows us to estimate how many people are likely to live near upstream flares under current flaring patterns by 2030. Results show that exposure is concentrated in a few oil-producing countries. Nigeria remains the most affected, with over 100,000 urban residents exposed in 2023. India and Pakistan dominate peri-urban and semi-urban exposures, while Indonesia and Iraq persist as multi-settlement hotspots. Although moderate declines are observed in China and Iran, little progress is evident in Nigeria, Mexico, and Indonesia. Projections for 2030 suggest exposure will increase substantially, driven by population growth and urban expansion, with about 2.7 million people living within 1 km and 14.8 million within 3 km of flaring sites. The findings establish the first globally consistent baseline for population exposure to gas flaring, supporting the monitoring and mitigation objectives of the Zero Routine Flaring by 2030 initiative. Full article

The increasing atmospheric carbon dioxide (CO₂) emissions are widely recognized as the primary driving force behind the phenomenon of global warming. Considering environmental concerns and the depletion of fossil fuel reserves, the use of electric vehicles (EVs) in transportation has emerged as one of the most promising technological alternatives to conventional gasoline-powered cars. Compared to their gasoline counterparts, EVs significantly reduce the costs associated with air pollution and mitigate adverse effects on human health. Owing to these characteristics, EVs have become one of the key components of the transition toward a sustainable future, while also steering the transformation of the global automotive industry. This transition is reshaping the structure of the global automobile industry. Many countries aim to achieve their greenhouse gas reduction targets by promoting the adoption of EVs. This study aims to empirically examine the effects of electric vehicles on CO₂ emissions in 15 high-income countries during the period 2010–2023, highlighting both short- and long-term environmental impacts. The analysis also considers economic and socio-demographic variables such as gross domestic product (GDP), urbanization, and fossil fuel consumption. The findings indicate that the share of EVs significantly reduces CO₂ emissions, whereas sales have a short-term increasing effect. Full article

Growing efforts to reduce air pollution have accelerated the development of advanced flue gas treatment technologies for coal-fired power plants. This study presents the design, development, and industrial-scale implementation of a microwave-assisted non-thermal plasma reactor, powered by a 75 kW, 915 MHz magnetron, for simultaneous sulfur dioxide (SO₂) removal and fly ash agglomeration. The reactor was installed on the outlet line of the selective catalytic reduction (SCR) system of a 22 MW_e pulverized-coal-fired boiler and evaluated under real flue gas conditions. The flue gas stream, extracted by an induced-draft fan, was supplied to the reactor through two configurations—radial and axial injection—to investigate the influence of gas flow rate and microwave power on SO₂ abatement performance. Under radial injection, the system achieved a maximum SO₂ removal efficiency of 99.0% at 5194 Nm³/h and 75 kW, corresponding to a specific energy consumption of 14.4 Wh/Nm³. Axial injection resulted in a removal efficiency of 97.5% at 4100 Nm³/h. Beyond SO₂ mitigation, exposure of flue gas to the microwave-assisted plasma environment significantly enhanced particle agglomeration, as confirmed by means of SEM imaging and particle size distribution analyses. Notably, the proportion of fine particles smaller than 2.5 µm (PM_2.5) decreased from 70.25% to 18.63% after plasma treatment, indicating improved capture potential in the downstream electrostatic precipitator (ESP). Overall, microwave-assisted plasma provides efficient SO₂ removal and enhanced particulate capture, offering a compact and potentially waste-free alternative to conventional systems. Full article

This study evaluates the abatement of four common azole fungicides—prochloraz, tebuconazole, tetraconazole, and penconazole—using ozonation (O₃), electro-oxidation (EO on boron-doped diamond anode), and their coupling (EO–O₃). A central composite design (CCD) with three coded factors—current (A), electrolyte (B), and ozone concentration in the gas phase (C)—was employed to model three responses: pollutant abatement (%), apparent pseudo-first-order rate constant k (min⁻¹), and TOC removal (%). Quadratic models showed good in-samples (R² ≈ 0.84–0.86). Ozone and current dominate abatement and kinetics (with curvature in current), while the electrolyte penalizes mineralization and narrows the window for TOC removal. Under optimal conditions, 116 mA (current), 0.992 mM (electrolyte), and 7.09 ppm (ozone concentration), the EO–O₃ configuration results in a TOC removal of 33.78%. At a reaction time of 10 min (total abatement of the pollutants), the hybrid EO–O₃ configuration exhibits a specific energy consumption (SEC) of 1.825 kWh·m⁻³. We compare trends with the last decade of literature on ozone-based EAOPs, electro-peroxone variants, and BDD anodic oxidation, and outline practical guidance for its application and scale-up, and model refinement in predictive settings. Full article

Remediating complex-contaminated soils demands the synergistic optimization of efficiency, cost-effectiveness, and carbon emission reduction. Currently, ultra-high-temperature thermal desorption technology is mature in terms of principle and laboratory-scale performance; however, ongoing efforts are focusing on achieving stable, efficient, controllable, and cost-optimized operation in large-scale engineering applications. To address this gap, this study aimed to (1) verify the energy efficiency and economic benefits of removing over 98% of target pollutants at a 7.5 × 10⁴ m³ contaminated site and (2) elucidate the mechanisms underlying parallel scale–technology dual-factor cost reduction and energy–carbon–cost optimization, thereby accumulating case experience and data support for large-scale engineering deployment. To achieve these objectives, a “thermal stability–chemical oxidizability” classification criterion was developed to guide a parallel remediation strategy, integrating ex situ ultra-high-temperature thermal desorption (1000 °C) with persulfate-based chemical oxidation. This strategy was implemented at a 7.5 × 10⁴ m³ large-scale site, delivering robust performance: the total petroleum hydrocarbon (TPH) and pentachlorophenol (PCP) removal efficiencies exceeded 99%, with a median removal rate of 98% for polycyclic aromatic hydrocarbons (PAHs). It also provided a critical operational example of a large-scale engineering application, demonstrating a daily treatment capacity of 987 m³, a unit remediation cost of 800 CNY·m⁻³, and energy consumption of 820 kWh·m⁻³, outperforming established benchmarks reported in the literature. A net reduction of 2.9 kilotonnes of CO₂ equivalent (kt CO₂e) in greenhouse gas emissions was achieved, which could be further enhanced with an additional 8.8 kt CO₂e by integrating a hybrid renewable energy system (70% photovoltaic–molten salt thermal storage + 30% green power). In summary, this study establishes a “high-temperature–parallel oxidation–low-carbon energy” framework for the rapid remediation of large-scale multi-contaminant sites, proposes a feasible pathway toward developing a soil carbon credit mechanism, and fills a critical gap between laboratory-scale success and large-scale engineering applications of ultra-high-temperature remediation technologies. Full article

This study is based on data obtained as part of continuous monitoring of small gas impurities (SO₂, NO₂, NO), mass concentration of aerosol particles PM_2.5 and meteorological parameters, which was first implemented at the Tankhoi observation point (southeastern coast of Lake Baikal, Russia) from October 2023 to May 2025. Statistical methods and the non-parametric wind regression receptor model (NWR) were used to analyze temporal variability and identify sources of pollution. It was found that the concentrations of gas impurities have a clearly pronounced winter maximum: the median values for sulfur dioxide and nitrogen in winter reached 9.2 μg/m³ and 13.8 μg/m³, respectively, which is associated with emissions from coal-fired thermal power plants and unfavorable meteorological conditions (inversions, low boundary layer height). In contrast to gases, PM_2.5 demonstrated a summer peak up to 43.5 μg/m³ in July–August 2024 due to abnormally hot weather and forest fires. The daily course of sulfur dioxide was characterized by an atypical daily maximum caused by the convective transport of polluted air masses from the upper layers of the boundary layer. During this period, higher concentrations of sulfur dioxide caused by long-range high-altitude transport of emissions from regional thermal power plants can reach the ground surface, leading to an increase in their concentration in the near-surface layer. Using the NWR model, the influence of regional thermal power plants located 100–150 km northwest of the station on the levels of SO₂ and NO₂ was confirmed. The results also highlight the contribution of local sources, such as vehicles, stoves, and shipping, to the formation of NO and PM_2.5. Full article

The depletion of fossil fuel reserves and the pollution produced by fuel combustion are major concerns in the energy generation sector. Due to this, waste heat recovery has become a stringent objective in this domain. The current study pursues this objective with regard to gas–steam combined cycle power plants, which are currently viewed as the most advanced technology in fossil fuel power generation. The proposed solution for waste heat recovery is to add an organic Rankine cycle (ORC) power system to the gas–steam combined cycle power plant with a Solar Centaur 40 gas turbine, produced by Solar Turbines, a Caterpillar Company (San Diego, CA, USA). The ORC power system is placed along the path of the flue gas, downstream of the heat recovery steam generator of the combined cycle power plant. R1336mzz (Z), R1233zd (E), and R601a were investigated as working fluids. The performance of the ORC system was analyzed as a function of the degree of superheat. The superheating process was proven to be disadvantageous since it led to performance deterioration. The numerical study showed that the overall efficiency of the combined cycle power plant increased up to 0.014 (1.4%) as a consequence of adding the ORC system, which itself achieves a maximum efficiency of 0.133 (13.3%). The annual fuel (natural gas) savings achievable under these conditions were roughly estimated at 398,185 Nm³/year, equating to annual fuel cost savings of approximately 269,000 EUR/year and an 810 t/year reduction in CO₂ emissions. Full article

For many years, Warsaw has been one of the European cities with the worst air quality, mainly due to harmful pollutants emitted by the residential sector and street traffic. This has led to high concentrations of particulate matter (PM), nitrogen oxides (NO_x), and also benzo alpha pyrene (BaP), often exceeding WHO standards. However, since 2010, there have been significant changes in the Polish energy mix, with a trend towards a decrease in the share of coal, with a simultaneous increase in the share of renewable energy sources and natural gas. The article presents the related effects of the relevant central government’s policy during the last decade, further supported by the pro-environment decisions of the Warsaw authorities. We also present trends in the concentration of harmful pollutants over the 2012–2023 decade as recorded by the air quality monitoring system. Complete pollution records for 2023 come from two air quality monitoring systems recently operating in the city (GIOŚ official stationary and AIRLY IoT sensor systems). Since the sensors of these systems are located at different sites, the average annual records of both systems were compared indirectly, using the computer simulation results of key pollutant propagation in 2023. Based on the tests conducted, the hypothesis of equality of the annual means for the results from both the monitoring systems and the modeling is not rejected, despite a seemingly clear underestimation of the IoT sensors’ recordings versus the official ones. The reasons for these differences are investigated through a direct comparison and analysis of the average monthly recordings from the monitoring systems. Full article

Conventional nitrogen fertilization in a maize cropping system enhances the soil’s methane (CH₄) sink but exacerbates emissions of nitrous oxide (N₂O) and nitric oxide (NO). This study demonstrates that conventional nitrogen application (UN) increased CH₄ uptake by 154%, while elevating N₂O and NO emissions by 190% and 301%, respectively, compared to zero nitrogen plots (N0). Fertilization fundamentally reconfigured the regulatory mechanisms governing gas fluxes: under UN, fluxes were controlled by a complex interplay of nitrogen substrates, carbon availability, moisture, and temperature, whereas under N0, CH₄ uptake exhibited significantly enhanced temperature sensitivity (with Q₁₀ increasing from 1.06 to 7.54) and nitrogen oxide emissions became more dependent on native ammonium and extractable organic carbon. Crucially, nitrogen withdrawal reduced soil ammonium by 37.1% without altering non-nitrogen soil properties, including temperature, moisture, and labile carbon pools. Collectively, these findings are consistent with the concept of nitrogen saturation under conventional fertilization rates. Optimizing these rates presents a significant opportunity to mitigate greenhouse gas emissions and air pollution while improving nitrogen use efficiency, thereby aligning agricultural production with climate goals and public health objectives without destabilizing short-term soil function. Full article

The escalating challenges of insecticide resistance and environmental pollution underscore the urgent need for sustainable and multi-functional biopesticides. This study reveals the chemical diversity and potent bioactivity of essential oils (EOs) from Neolamarckia cadamba, highlighting their potential as a valuable source of bioactive agents. Gas chromatography–mass spectrometry analysis revealed a striking contrast between the essential oils: the stem bark EO was dominated by methyl salicylate (MeSA, 97.61%), representing the first report of MeSA as a major constituent in this species, while the leaf oil exhibited a complex profile enriched with diterpenoids (25.09%) and fatty acids (23.21%). Both EOs exhibited significant insecticidal efficacy against Aedes aegypti, demonstrating rapid knockdown with median knockdown times (KT₅₀) of 1.36–1.97 min—surpassing the synthetic dimefluthrin. Additionally, they demonstrated pronounced toxicity, with median lethal concentrations (LC₅₀) of 73.41–75.27 μg/mL and fumigant toxicity values of 0.20–0.22 μL/L. Notably, the major component MeSA in the stem bark EO demonstrated obvious insecticidal potential, exhibiting rapid knockdown activity (KT₅₀ of 2.29 min), fumigant toxicity (LC₅₀ of 1.55 μL/L, 5 h), and poisonous activity (LC₅₀ of 92.67 μg/mL, 24 h). Meanwhile, both the stem bark EO and MeSA exhibited strong antifungal activity against the phytopathogen Rhizoctonia solani, with median effective concentration (EC₅₀) values of 48.70 and 53.91 μg/mL, respectively. This efficacy surpassed that of the commercial fungicide physcion (EC₅₀ of 93.34 μg/mL). Additionally, the EOs demonstrated moderate antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Mechanistic investigations revealed that the antifungal action of MeSA involved severe cellular disruption, including ultrastructural damage, membrane peroxidation, and critical metabolic suppression via the inhibition of succinate dehydrogenase activity. Our results clearly established N. cadamba EOs, particularly the MeSA-rich stem bark oil, as potent, plant-based, and multi-target agent with significant potential for integration into sustainable pest and disease management strategies. Full article

The implementation of ultra-low emission standards in the steel industry imposes higher demands on flue gas purification. Carbon-based materials, leveraging their porous structure and surface activity, demonstrate high adsorption potential for treating heavy metal ions, sulfur- and nitrogen-containing compounds, and volatile organic pollutants. However, their application is constrained by a limited selective adsorption capacity. This paper systematically analyzes the mechanisms by which carbon-based materials treat water, air, and soil pollutants; investigates their physical and chemical degradation patterns; and summarizes practical physicochemical modification pathways. Research indicates that modification techniques can effectively overcome performance limitations of carbon-based materials, enhance pollutant adsorption efficiency, and provide new insights for the engineering application of multi-media pollution synergistic control and environmental remediation technologies. Full article

The global fight to mitigate greenhouse gas emissions and address climate change demands that firms implement energy-saving strategies while maintaining firm financial performance. However, the impact of energy efficiency on corporate financial performance remains underexplored, especially in South Africa. This study applied a two-step system generalized method of moments (SGMM) to explore the impact of energy efficiency on the financial performance of higher polluters and emitters listed on the Johannesburg Stock Exchange (JSE) over the period from 2015 to 2023. The sample for the study was 58 companies listed on the JSE. The data was sourced from the firm’s annual reports covering the period of 9 years (2015–2023). Our study reveals no significant association between energy-saving strategies and firm financial performance within high-polluting and emitting firms listed on the JSE. Notably, the study reports that leverage positively affects both firm profitability and market valuation, suggesting that debts may serve as a dynamic capability for improving firm performance if it is used strategically. Our findings underscore the importance of mandatory independent assurance of ESG reports to mitigate greenwashing risks. Full article

Mining activities have caused widespread land degradation and contamination, affecting millions of hectares worldwide and posing persistent ecological risks. However, reclamation substrates are constrained by limited availability and compromised quality, which restricts their ability to fully support mine ecological restoration. Among various amendment materials, biomass-based amendments have been widely applied due to their broad availability, renewability, biodegradability, and low cost. In recent years, their role has expanded beyond simple nutrient supplementation to encompass multiple functions, including structural optimization, pollutant stabilization, and microbial regulation. This review highlights the valorisation of biomass-derived solid wastes as multifunctional amendments for mine ecological restoration. By converting agricultural and industrial wastes into green materials, these amendments improve substrate structure, stabilize heavy metals and organic pollutants, enhance nutrient cycling, and stimulate microbial activity. Potential risks, including nutrient leaching, secondary pollution, and greenhouse gas emissions, are critically assessed, with emphasis on their variability under different environmental conditions. By integrating functional benefits with ecological risks, this work underscores the critical role of biomass-based amendments as waste-to-resource strategies in advancing sustainable mine reclamation, contributing to circular economy goals, and supporting environmental engineering practices. Full article

Achieving sustainable air quality improvements in rapidly industrializing regions requires a clear understanding of the emission sources that drive the formation of PM_2.5 pollution. This study identified the sources of PM_2.5 and its organic carbon (OC) in Zibo, a typical industrial city in Northern China Plain, using the Positive Matrix Factorization (PMF) model during five pollution episodes (P1–P5) from 26 November 2022 to 9 February 2023. A high-temporal-resolution online observation of 61 organic molecular tracers was conducted using an Aerodyne TAG stand-alone system combined with a gas chromatograph–mass spectrometer (TAG-GC/MS) system. The results indicate that during pollution episodes, PM_2.5 was contributed by 32.4% from coal combustion and 27.1% from inorganic secondary sources. Moreover, fireworks contributed 13.1% of PM_2.5, primarily due to the extensive fireworks during the Gregorian and Lunar New Year celebrations. Similarly, coal combustion was the largest contributor to OC, followed by mobile sources and secondary organic aerosol (SOA) sources, accounting for 16.2% and 15.3%, respectively. Although fireworks contributed significantly to PM_2.5 concentrations (31.6% in P4 of 20–24 January 2023), their impact on OC was negligible. Overall, a combination of local and regional industrial combustion emissions, mobile sources, extensive residential heating during cold weather, and unfavorable meteorological conditions led to elevated secondary aerosol concentrations and the occurrence of this haze episode. The high-temporal-resolution measurements obtained using the TAG-GC/MS system, which provided more information on source-indicating organic molecules (tracers), significantly enhanced the source apportionment capability of PM_2.5 and OC. The findings provide science-based evidence for designing more sustainable emission control strategies, highlighting that the coordinated management of coal combustion, mobile emissions, and wintertime heating is essential for long-term air quality and public health benefits. Full article