Search Results (5,114)

As industrial waste gas, nitrogen dioxide (NO₂) is a serious hazard to air pollution and human health, and there is a pressing demand for developing high-performance NO₂ gas sensors. Tin disulfide (SnS₂), a representative two-dimensional metal sulfide characterized by a significant specific surface area, a suitable electron band gap, and an easily tunable layered structure, shows a broad application prospect in gas sensing applications. Nevertheless, SnS₂-based gas sensors suffer from poor sensitivity, which seriously hinders their application in room temperature gas sensing. In this study, Ag/SnS₂ heterojunction nanomaterials were synthesized by an in situ reduction approach. The findings reveals that the gas-sensitive response of the Ag/SnS₂ nanocomposites at room temperature under visible light irradiation can achieve 10.5 to 1 ppm NO₂, with a detection limit as low as 200 ppb, which realizes the room-temperature detection of Sub-ppm NO₂. Meanwhile, the sensor exhibits good selectivity, reproducibility (cyclic stability > 95%). The improved gas sensitivity of the Ag/SnS₂ sensor can be due to the synergistic effect of the carrier separation at the Ag/SnS₂ Schottky junction and the localized surface plasmon resonance (LSPR) of Ag nanoparticles. The LSPR effect significantly enhances light absorption and surface-active site density, facilitating trace NO₂ detection at room temperature. This study provides the foundation for the subsequent development of room temperature layered metal sulfide gas sensors. Full article

Plastic pollution is a pressing global environmental challenge, and low-density-polyethylene (LDPE) is among the most persistent synthetic polymers. This study investigates the in vitro biodegradation of LDPE by native Aspergillus strains isolated from plastic-contaminated soils in Trujillo, Peru. Molecular techniques were used to identify the Aspergillus species. The LDPE strips were incubated for 50 days, and biodegradation was evaluated by weight loss (%), pH variation, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Likewise, the reduction rate and half-life of the polymer (t_1/2) were calculated. Three strains of Aspergillus—A. niger H1C, A. ochraceopetaliformis H3C, and A. tamarii H6C—were isolated and evaluated for their ability to LDPE under in vitro conditions. A. niger H1C exhibited the most weight reduction (4.25 ± 1.67%) and a polymer half-life of 897.89 days, while A. tamarii H6C demonstrated a comparable loss (3.79 ± 1.52%) with a half-life of 901.6 days. A. ochraceopetaliformis H3C exhibited a moderate degradation (1.98 ± 0.37%), with the longest half-life recorded at 1757.33 days. The process was supported by pH variations. Furthermore, FTIR and SEM analyses revealed structural modifications in LDPE including formation of hydroxyl, carbonyl, and ether groups, suggesting oxidative and enzymatic activity-possibly mediated by lipases induced under lipid-rich conditions. This is the first report of A. ochraceopetaliformis and A. tamarii, highlighting their potential in sustainable plastic bioremediation strategies aligned with SDG 13 (Climate Action). Full article

To address the greenhouse effect and environmental pollution stemming from fossil fuels, the development of new energy sources is widely regarded as a critical pathway toward achieving carbon neutrality. Microalgae, as a feedstock for third-generation biofuels, have emerged as a research hotspot for producing biojet fuel due to their high photosynthetic efficiency, non-competition with food crops, and potential for carbon reduction. This paper provides a systematic review of technological advancements in the catalytic hydrogenation of microalgal oil for biojet fuel production. It specifically focuses on the reaction mechanisms and catalyst design involved in the hydrogenation–deoxygenation and cracking/isomerization processes within the Oil-to-Jet (OTJ) pathway. Furthermore, the paper compares the performance differences among various catalyst support materials and between precious and non-precious metal catalysts. Finally, it outlines the current landscape of policy support and progress in industrialization projects globally. Full article

Reducing food loss and waste (FLW) is a global priority under UN SDG 12.3, yet Taiwan has lacked stage-specific FLW data and systematic valuation of its environmental and economic implications. This study addresses these gaps by integrating localized FLW estimates from the APEC-FLOWS database with an enhanced analytical framework—the Environmentally Extended Input–Output Valuation (EEIO-V) model. The EEIO-V extends conventional input–output analysis by monetizing multiple environmental burdens, including greenhouse gases, air pollutants, wastewater, and solid waste, thereby linking FLW reduction to tangible economic benefits and policy design. The simulations reveal substantial differences in environmental cost reductions across supply chain stages, with downstream interventions delivering the largest benefits, particularly in reducing air pollution and greenhouse gases. By contrast, upstream measures contribute relatively smaller improvements. These findings highlight the novelty of EEIO-V in bridging environmental valuation with system-level FLW analysis, and they provide actionable insights for designing cost-effective, stage-specific strategies that prioritize downstream interventions to advance Taiwan’s sustainability and policy goals. Full article

This study aims to explore the role of government environmental auditing in promoting China’s coordinated goals of “pollution reduction, carbon mitigation, ecological expansion, and growth.” By analyzing 1959 panel data from 227 prefecture-level cities in China between 2011 and 2022, a four-dimensional evaluation framework was constructed, and empirical testing was carried out using a double machine learning method. The results indicate that environmental auditing significantly enhances the synergy of environmental governance, mainly by raising public environmental awareness, promoting industrial clustering, and fostering green innovation. Additionally, green finance provides complementary support to this process. This effect is particularly pronounced in regions with higher levels of marketization, more developed financial technology, and greater environmental expenditure. Based on these findings, this study concludes that environmental auditing plays a crucial role in promoting China’s coordinated goals of “pollution reduction, carbon mitigation, ecological expansion, and growth.” In particular, environmental auditing demonstrates its institutional value in promoting sustainable governance, especially in developing economies. Full article

Pharmaceuticals are emerging contaminants of global concern, but their occurrence and removal in semi-arid regions such as Algeria remain poorly documented. This study provides the first systematic evaluation of pharmaceutical and physicochemical parameters in two wastewater treatment plants (WWTPs) in Mascara: an activated sludge system (WWTP-1) and an aerated lagoon system (WWTP-2). Ten pharmaceuticals of different therapeutic classes were quantified using UPLC-HR-QTOF-MS in influent, effluent, and sludge samples, and removal efficiencies were compared using ANOVA and Principal Component Analysis (PCA). WWTP-1 showed higher efficiency, with >90% removal of COD, BOD₅, and ammonium, and near-complete elimination of sulfamethoxazole (99.9%) and atenolol (94%). In contrast, WWTP-2 achieved only moderate reductions (69% COD, 51% BOD₅) and low pharmaceutical removal, with negative efficiencies for persistent compounds such as carbamazepine, diclofenac, and ibuprofen. Weak correlations between macro- and micropollutants indicated that traditional indicators cannot predict pharmaceutical behavior. This work is the first to integrate physicochemical monitoring, pharmaceutical profiling, and multivariate analysis in Algerian WWTPs. The findings highlight the limitations of conventional treatment in semi-arid conditions and provide a critical baseline for adopting advanced technologies to mitigate pharmaceutical pollution in North Africa. Full article

The utilization of carbon dioxide (CO₂) offers an effective approach for alleviating the carbon-reduction pressures associated with fossil energy consumption. However, studies on the use of CO₂ as an auxiliary agent in water treatment to enhance the removal of emerging contaminants are limited. In this study, the photodegradation of ciprofloxacin (CIP) was investigated using ultraviolet (UV) irradiation combined with CO₂ dosing (UV/CO₂). The results demonstrated that the UV/CO₂ system effectively degraded CIP, with CO₂ concentration and solution pH exerting a critical influence. Inorganic anions and metal cations had negligible effects on CIP degradation efficiency, whereas natural organic matter (NOM) had a pronounced inhibitory effect. Mechanistic analysis revealed that superoxide radicals ($·{\mathrm{O}}_2^{-}$) and carbonate radicals (${\mathrm{CO}}_3^{•-}$) were the primary oxidizing species, whereas the excited triplet state of CIP (³CIP*) and singlet oxygen played crucial roles in initiating radical generation. LC–MS analysis and density functional theory calculations indicated that the main degradation routes involved defluorination, decarboxylation, and epoxidation of the piperazine ring. Toxicity assessment indicated that the transformation products generated by UV/CO₂ were less toxic than the parent compound. Furthermore, the UV/CO₂ process demonstrated high energy efficiency, with a low electrical energy per order (EEO) value of 0.4193 kWh·m⁻³·order⁻¹. These findings suggest that the UV/CO₂ system is a promising alternative for the treatment of photosensitive organic pollutants and provides a beneficial pathway for CO₂ utilization. Full article

The concentration characteristics of SO₂, NO₂, O₃, and CO in the marine atmosphere are of great significance for understanding air–sea interactions and regional atmospheric chemical processes. However, due to the challenging conditions of marine monitoring, long-term continuous observational data remain scarce. To address this gap, this study proposes a Transfer Learning–Convolutional Neural Network (TL-CNN) model that integrates ERA5 meteorological data, EAC4 atmospheric composition reanalysis data, and ground-based observations through multi-source data fusion. During data preprocessing, the Data Interpolating Empirical Orthogonal Function (DINEOF), inverse distance weighting (IDW) spatial interpolation, and Gaussian filtering methods were employed to improve data continuity and consistency. Using ERA5 meteorological variables as inputs and EAC4 pollutant concentrations as training targets, a CNN-based inversion framework was constructed. Results show that the CNN model achieved an average coefficient of determination (R²) exceeding 0.80 on the pretraining test set, significantly outperforming random forest and deep neural networks, particularly in reproducing nearshore gradients and regional spatial distributions. After incorporating transfer learning and fine-tuning with station observations, the model inversion results reached an average R² of 0.72 against site measurements, effectively correcting systematic biases in the reanalysis data. Among the pollutants, the inversion of SO₂ performed relatively poorly, mainly because emission reduction trends from anthropogenic sources were not sufficiently represented in the reanalysis dataset. Overall, the TL-CNN model provides more accurate pollutant concentration fields for offshore regions with limited observations, offering strong support for marine atmospheric environment studies and assessments of marine ecological effects. It also demonstrates the potential of combining deep learning and transfer learning in atmospheric chemistry research. Full article

South Korea faces high levels of air pollution and is currently not on track to meet its transport sector 2030 and 2050 greenhouse gas emission reduction targets primarily due to infrastructural limitations. This study examines the potential health benefits of a more rapid green transition of South Korea’s transport sector from 2026 to 2050 in terms of avoided premature deaths and years of life lost due to reduced ambient PM_2.5 exposure. The research conducts a scenario analysis comparing the business-as-usual trajectory of the transport sector with two alternative scenarios. In the first alternative scenario, South Korea’s transport sector achieves its 2030 NDC in 2035 and carbon neutrality in 2050 with a reliance on CCUS for emission capture. The second alternative scenario entails stronger climate action in which the transport sector meets the 2030 NDC target in 2030 and the 2050 carbon neutrality transport sector target through a complete green transition to electric vehicles and hydrogen vehicles. The first alternative scenario results in an average of 80 avoided premature deaths (775 avoided years of life lost) and 53 MTCO₂e avoided emissions per year from 2026 to 2050. The second more rapid green transition scenario of South Korea’s transport sector achieves an average of 96 avoided premature deaths (925 avoided years of life lost) and 66 MTCO₂e avoided emissions per year. This research supports a more rapid green transition of South Korea’s transport sector for both health and climate gains. Full article

We investigated the application of an adsorbent fabricated from satsuma mandarin peel biomass using coating with poly(glycidyl methacrylate) followed by sequential treatment with hydroxylamine and hydrochloric acid for the remediation of hexavalent chromium-polluted water. The adsorbent was characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Batch adsorption experiments were conducted wherein initial solution pH, initial chromium concentration, contact time, and temperature were varied. The adsorption equilibrium experimental data were well simulated by the Langmuir and Jovanovic models, pointing toward the formation of a monolayer of adsorbed chromium ions. The total chromium adsorption capacity of the functionalized satsuma mandarin peel adsorbent reached 219.28 mg g⁻¹ at initial pH 1.4 and 60 °C, markedly higher than 110.23 mg g⁻¹ at 30 °C. Where Cr(VI) was the sole chromium oxidation state in the initial solutions synthesized from potassium dichromate, the presence of Cr(III) ions in the final solutions confirmed Cr(VI) reduction. The results of this study show that the functionalized satsuma mandarin peel biomass is a potential candidate for use in the removal of hexavalent chromium from aqueous solution through reduction-coupled adsorption. Full article

Urban soils are often affected by long-term deposition of persistent organic pollutants, including polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). This study evaluated the biodegradation potential of indigenous bacterial strains isolated from chronically contaminated soils in Lausanne, Switzerland. Using selective enrichment techniques, five strains were isolated, with no biosafety concerns for human health and environmental applications. These isolates were screened for their ability to degrade dibenzofuran (DBF) and 2,7-dichlorodibenzo-p-dioxin (2,7-DD) under mineral medium conditions. A simplified two-strain consortium (Acinetobacter bohemicus and Bacillus velezensis) and a broader five-strain co-culture were then applied to real soil microcosms over a 24-week period. This work provides the first experimental evidence that A. bohemicus and B. velezensis can degrade DBF and 2,7-DD under controlled conditions. Dioxin concentrations were monitored at 4, 8, and 24 weeks using a Gas Chromatography Mass Spectrometry (GC-MS). In laboratory conditions, co-cultures showed enhanced degradation compared to individual strains, likely due to metabolic complementarity. In soil, the simplified two-strain consortium performed better at dioxin degradation, especially at earlier time points. Although no statistically significant reductions were observed due to high variability and limited sample size, consistent trends emerged, particularly at the most contaminated site. These findings support the relevance of testing bioremediation strategies under realistic environmental conditions. Full article

Understanding the dose of ambient PM_2.5 inhaled by middle school students during active commuting between home and school is essential for optimizing their travel routes and reducing associated health risks. However, accurately modeling this remains challenging due to the difficulty of measuring ambient PM_2.5 concentrations along commuting routes at a population scale. In this study, we overcome this limitation by employing spatiotemporally dense observations of on-road ambient PM_2.5 concentrations collected through a massive mobile monitoring fleet consisting of around 200 continuously operating taxis installed with air quality monitoring instruments. Leveraging these rich on-road PM_2.5 observations combined with a GIS-terrain-based PM_2.5 dosage modeling approach, we (1) assess middle school students’ PM_2.5 dosages during morning (7:00 am–8:00 am) home–school walking commuting along the shortest-distance route; (2) examine the feasibility of identifying an alternative route for each student that minimizes PM_2.5 dosages during commuting; (3) investigate the trade-off between the relative reduction in PM_2.5 dosage and the relative increase in route length when opting for the alternative lowest-dosage route; and (4) examine whether exposure inequalities exist among students of different family socioeconomic statuses (SES) during their home–school commutes. The results show that (1) 18.8–57.6% of the students can reduce the dose of PM_2.5 by walking along an alternative lowest-dose route; (2) an alternative lowest-dose route could be found by walking along a parallel, less-polluted local road or walking on the less-trafficked side of the street; (3) seeking an alternative lowest-dose route offers a favorable trade-off between effectiveness and cost; and (4) exposure inequities do exist in a portion of students’ walking commutes and those students from higher-SES are more likely to experience higher exposure risks. The findings in our study could offer valuable insights into commuter exposure and inspire future research. Full article

Air quality is a vital factor for safeguarding public and environmental health. Particulate matter (i.e., PM2.5 and PM10) and nitrogen dioxide are among the most harmful air pollutants leading to severe health risks such as respiratory and cardiovascular diseases, while also affecting the environment negatively by contributing to the formation of acid rains and ground level ozone. The European Union has introduced new thresholds on those pollutants to be met by the year 2030, taking into consideration the guidelines set by the World Health Organization, aiming for a healthier environment for humans and living species. Cyprus is an island that is vulnerable to those pollutants mostly due to its geographic location, facilitating shipping activities and dust transport from Sahara Desert, and the methods used to produce electricity which primarily rely on petroleum products. Furthermore, the country suffers from heavy traffic conditions, making it susceptible to high levels of nitrogen dioxide. Thus, the projection of air pollutants according to different scenarios based on regulations and policies of the European Union are necessary towards clean air and better practices. The Screening for High Emission Reduction Potential on Air (SHERPA) is a tool developed by the European Commission which allows the simulation of emission reduction scenarios and their effect on the following key pollutants: NO, NO₂, O₃, PM2.5, PM10. This study aims to assess the potential of the SHERPA simulation tool to support air quality related decision and policy planning in Cyprus to ensure that the country will remain within the thresholds that will be applicable in 2030. Full article

Achieving carbon emission reduction synergy is vital for green economic transformation. This study examines whether environmental governance pressure promotes such synergy, simultaneously driving carbon reduction and pollution control. Leveraging the 2012 Ambient Air Quality Standard as a quasi-natural experiment, we employ a continuous difference-in-differences (DID) method on 250 prefecture-level cities from 2009 to 2022. Our findings reveal that increased environmental governance pressure significantly reduces both the total amount and intensity of carbon emissions, demonstrating a clear synergistic effect. This synergy is positively correlated with reductions in major air pollutants (e.g., SO₂ and NO_x), indicating that pressure curbs both the total amount and intensity of carbon emissions. Mechanistic analysis shows that this pressure primarily curtails carbon emissions by fostering green innovation and accelerating cleaner energy transitions, with no ‘green paradox’. It also promotes low-carbon industrial restructuring while reducing reliance on end-of-pipe pollution management. Heterogeneity analysis indicates stronger synergistic effects in regions with lower emission reduction costs (e.g., western China, less developed industrial bases). We recommend robust central government environmental regulation policies to amplify local governance pressure, strengthen carbon reduction synergy, and facilitate continuous green development. Full article

As cattle are criticized for contributing to environmental problems by emitting pollutants, it is expected that environmental regulations on livestock will be strengthened. This will lead to an increase in the costs and benefits associated with these regulations. This paper develops a model that clearly shows the effects of environmental regulations on the production costs for cattle-breeding farmers and the changes in social welfare, as well as environmental benefits. The benefits associated with the regulation are measured by evaluating reductions in both greenhouse gas (GHG) and ammonia emissions. These benefits are then compared to the reduction in social welfare. According to the analysis, the reduction in social welfare, in terms of consumer and producer surplus, outweighs the environmental benefits. These results suggest that, in designing environmental regulations, policy measures are needed to alleviate producers’ economic burdens and minimize reductions in social welfare through byproduct utilization and technical support. Furthermore, this study contributes to laying the institutional foundation for the sustainable development of the livestock industry and the reduction in management costs associated with manure treatment. Full article