Environmental Science and Pollution Research最新文献

Ethylenediaminetetraacetic acid (EDTA), extensively used across multiple industries, has long been discussed for its potential to enhance heavy metal mobility in aquatic systems, with studies yielding contradictory results. This study examines the remobilization of particle-bound lead from suspended particulate matter (SPM) in the Innerste River (Lower Saxony, Germany), which is affected by historical mining and known for substantial Pb contamination. Using real river water containing its native SPM to preserve the chemical matrix of the system, we assessed Pb partitioning between total and dissolved phases to evaluate EDTA's remobilization potential. Baseline dissolved lead concentrations reached up to 1.8 µg L^-1 (median 0.69 µg L^-1). Across all batch experiments, a measurable increase in the dissolved Pb fraction occurred only at EDTA concentrations far exceeding those measured in the river (0.68-3.8 µg L^-1). Bayesian concentration-response modelling yielded no-effect concentrations (NEC) between 210 and 530 µg L^-1. Complementary speciation modelling showed that shifts in Pb speciation occur only at EDTA concentrations near the experimentally derived NEC values. These findings show that current EDTA concentrations in the Innerste are unlikely to remobilize Pb from SPM. The study also provides a statistically supported NEC estimate based on batch experiments using unaltered river water containing its naturally present SPM. To our knowledge, this is the first application of Bayesian NEC modelling to EDTA-induced Pb remobilization.

Objective: This study aims to examine the relation between daily maximum exposure to Particulate Matter (PM_2.5), high wind speed, and minimum visibility, and COVID-19 cases in El Paso County, Texas, a dust-prone region. A time-series analysis using a generalized linear model with a Poisson model was employed to analyze relative risks of COVID-19 cases in El Paso (March 2020 to November 2021). A total of 156,299 cases were diagnosed during the study period. A 10 μg/m³ increase in PM_2.5 levels was linked with higher risk ratio (RR) of COVID-19 (Lag Days 1 to 3) [lag1: RR = 1.004; 95% CI: (1.003-1.005), lag2: RR = 1.006; 95% CI: (1.005-1.007), & lag 3: RR = 1.004; 95% CI: (1.003-1.005)], followed by a decrease in cases. Similarly, a 4.47 m/s rise in maximum wind speed was associated with an elevated RR of cases on Lag Day 4 [lag4: RR = 1.009; 95% CI: (1.003-1.014)], after which numbers begin to drop. Finally, a 4.83 km decrease in minimum daily visibility was correlated with an increased RR of cases on Lag Days 1 and 2 [lag1: RR = 1.031; 95% CI: (1.023-1.039), & lag2: RR = 1.018; 95% CI: (1.011-1.024)], with a decrease on Lag days 3, 4 and 5 and resurgence on Lag days 6 and 7 [lag6: RR = 1.028; 95% CI: (1.021-1.036), & lag7: RR = 1.046; 95% CI: (1.038-1.055)]. PM_2.5, wind speed, and visibility influencing COVID-19 cases in El Paso highlight the need for evidence-based interventions, including information, education, and communication programs, early-warning systems, cross-border air-quality management, real-time monitoring, and stricter emission controls.

In this study, TiO₂@hydrochar composite catalysts were prepared using solvothermal (ST), sol-gel (SG), and impregnation (I) methods for Acid Red 97 (AR97) degradation in aqueous solutions. Hydrochar (HC) was derived from wastewater of the ice cream industry via hydrothermal carbonization (HTC). This approach presents a sustainable strategy for transforming waste into resources by converting industrial wastewater into a valuable material. The prepared catalysts were characterized and then applied in photocatalytic tests. The results showed that [TiO₂@HC]_(SG), [TiO₂@HC]_(ST), and [TiO₂@HC]_(I) composites showed significantly improved catalytic activity compared to pure TiO₂, with [TiO₂@HC]_(ST) showing the highest activity, achieving 98.88% degradation efficiency under optimal conditions. After five cycles, this catalyst maintained 88.8% of its efficiency. Quenching experiments confirmed that the ^•OH radical played a crucial role in AR97 photodegradation. Overall, the findings reveal a promising eco-friendly strategy for environmental protection, utilizing industrial wastewater-derived hydrochar to improve the photocatalytic performance of TiO₂.

Cyanide is extensively used in hydrometallurgical leaching due to its strong metal-chelating ability, yet its acute toxicity raises major environmental concerns. This study evaluates photoactivated BiVO₄ synthesized by the sol-gel method and combined with ozone for the degradation of metal-cyanide complexes in alkaline matrices (pH 10.5) containing silver, copper, iron, lead, and zinc, representative of effluents from silver leaching in the Mexican mining industry. Synthetic solutions were prepared and characterized to reproduce these conditions. Thermodynamic stability diagrams indicated that free cyanide and complexes such as Ag(CN)₂⁻, Cu(CN)₃²⁻, and Fe(CN)₆⁴⁻ persist at alkaline pH, while lead and zinc showed no tendency to form stable cyanide complexes. Oxidative treatments favored complex dissociation, with cyanate predicted as the main by-product; experimentally, ammonium was identified as the dominant degradation product. The BiVO₄/ozone system under irradiation demonstrated superior performance compared to individual processes, achieving faster cyanide abatement and improved efficiency. Kinetics followed a modified Langmuir-Hinshelwood model that accounted for both surface-mediated photocatalysis and bulk-phase ozone reactions. Complete cyanide removal was achieved in two consecutive cycles, though partial deactivation occurred in the third cycle due to BiVO₄ surface poisoning by adsorbed metals, confirmed by SEM/EDS and atomic absorption. Despite gradual loss of activity, the coupled process consistently removed both free and complexed cyanide while reducing ozone demand compared with conventional ozonation. These findings highlight photocatalytic ozonation with BiVO₄ as a promising and sustainable strategy for the treatment of metallurgical effluents, offering efficient pollutant degradation and lower oxidant consumption in comparison with conventional approaches.

The cultivation of Daucus carota L. (carrot)  on soils polluted with trace elements (TE) constitutes an innovative phytomanagement approach, combining significant ecological and economic benefits. This plant species exhibits a notable capacity to extract trace elements from the soil while generating valuable biomass, primarily intended for hydrodistillation to produce high-quality essential oils (EO). Carrots exhibit an enhanced capacity to accumulate cadmium in their leaf tissues, with a high bioconcentration factor (BCF = 1.71), as well as significant zinc accumulation. Furthermore, the cultivation of this biennial plant promotes an increase in soil microbial biomass, as assessed by phospholipid fatty acid (PLFA) content, specifically enriching populations of Gram- bacteria, Gram+ bacteria, and saprotrophic fungi, thereby contributing to the modulation of microbial dynamics and the alleviation of stress within soil microbial communities. The EO extracted from carrot seeds contain TE concentrations below the quantification limit compared to other commercially available EO. Chemical analysis of the EO reveals a composition similar to that of commercial oils, with the major components being carotol (27.53%), an oxygenated sesquiterpene, and sabinene (26.08%), a monoterpene hydrocarbon. These EO have been extensively evaluated for their biological properties, demonstrating significant antifungal activity against Fusarium culmorum (IC50 = 0.57 ± 0.11 mg/ml) and Zymoseptoria tritici (IC50 = 1.09 ± 0.12 mg/ml), as well as antigermination activity against Blumeria graminis spores (IC50 = 1.47 ± 0.15 mg/ml). Additionally, these EO exhibit notable herbicidal properties, particularly in inhibiting root elongation and germination of the monocots species Lolium perenne (ryegrass) and the dicots species Lactuca sativa (lettuce). These findings highlight the potential of carrot as a tool for phytoremediation and the production of high-value bioactive compounds.

This study aimed to develop a comprehensive risk profile of four key occupational harmful factors-heat stress, inadequate illumination, noise, and respirable dust-within a representative ceramic manufacturing facility in Iran. Standardized instruments and protocols were used to assess four physical harmful factors. Dust concentration was measured via NIOSH 0600 using SKC pumps and nylon cyclones. Noise levels were recorded with a type 2 sound level meter (Extech 407732). Illuminance was measured with a GM1040 lux meter at a height of 0.85 m, and heat stress was evaluated using a wet-bulb globe temperature (WBGT) meter. The risk ratio (RR) was calculated for each harmful factor as a single risk index. An integrated risk assessment followed, incorporating RR values, the number of exposed workers, and exposure duration. Prioritization of harmful factors and similar exposure groups (SEGs) was performed using the Pareto principle. The findings revealed that the average levels of noise, illumination, respirable dust, and temperature in the studied ceramic industry were 82.88 dB(A), 114.83 lx, 4.15 mg/m³, and 21.01 °C, respectively. The RR matrix analysis identified respirable dust exposure as a high-risk factor, with a prioritization index exceeding 386%. In comparison, noise was classified as a medium-risk factor, with priority levels ranging from 321 to 386%. In contrast, poor illumination and heat stress were categorized as low-risk factors (integrated risk assessment (IRI) < 321%). Among the SEGs, the packing occupational group exhibited the highest comprehensive risk profile (IRI ≥ 379%) and was consequently identified as the top priority for control interventions in accordance with the Pareto principle. This risk-based framework offers a systematic approach for prioritizing occupational health interventions and optimizing resource allocation in industrial environments. Clinical trial number: This is not applicable.

An eco-friendly mesoporous silica gel (SG) was synthesized from raw Tunisian sand and evaluated for the adsorption of the toxic crystal violet (CV) dye from water. The SG was characterized using XRD, FTIR, SEM-EDX, N2 physisorption, TGA, and ZP. Structural analysis confirmed an amorphous phase and identified surface silanol (Si-OH) groups. The material exhibited a highly porous morphology and a pure SiO₂ composition. N₂ physisorption analysis revealed a high specific surface area of 103 m²/g and a mesoporous structure with an average pore diameter of 19 nm. ZP measurements confirmed a negative surface charge, thereby promoting the uptake of CV. Effective adsorption conditions were identified as pH 10, an adsorbent dosage of 0.05 g, and a contact time of 30 min. Equilibrium isotherms were well described by both Langmuir and Freundlich models, with a maximum uptake of 164 mg/g. The adsorption kinetics were best described by the pseudo-second-order model. The SG demonstrated remarkable stability, retaining 84% over three consecutive cycles. These findings confirm that the derived SG is reliable and stable, highlighting the successful valorization of natural sand for environmental remediation.

Plastic pollution has emerged as a pervasive environmental threat, with polyvinyl chloride (PVC) being a persistent polymer that can degrade into smaller fragments. These particles contaminate aquatic environments, accumulate in biota, and pose serious ecological and health risks. This study used computational methods to investigate the adsorption of vinyl chloride (VC), a PVC oligomer, onto montmorillonite (MMT). Vienna Ab initio Simulation Package was used to perform Density Functional Theory calculations. The interaction between VC and MMT was assessed through binding energy, density of states (DOS), projected DOS, and charge analysis. A negative binding energy (- 0.62 eV) confirmed favorable adsorption. The reduced HOMO-LUMO gap in the VC-MMT hybrid indicated electronic interactions. The orbital-resolved projected density of states (PDOS) showed overlap between the O 2p orbitals of MMT and the H 1 s orbitals of VC. Bader charge analysis revealed negligible charge transfer to the VC molecule upon adsorption, while charge density difference showed localized electron redistribution at the VC-MMT interface. These results indicate a noncovalent interaction without the formation of shared charge density, consistent with polarization-driven physisorption. Molecular dynamics simulations supported these interactions, showing that the VC molecule remained associated with the MMT surface through noncovalent forces. Root mean square deviation (RMSD) confirmed that the VC-MMT structure remained stable throughout the simulation, while the interaction energy exhibited stable fluctuations over time. These findings suggest that MMT holds potential as an effective sink for PVC microplastics through stable, non-covalent surface retention, thereby reducing their dispersion in environmental matrices.

Lakes Koka and Ziway in the Central Rift Valley (CRV) of Ethiopia are essential socio-ecological systems that provide water for domestic use, irrigation, hydropower, and fisheries, while also sustaining diverse biological communities. However, these lakes are under severe ecological stress due to intensifying anthropogenic pollution from industrial, agricultural, and urban sources. This review synthesizes multidisciplinary evidence on pollution sources, types, and ecological consequences, focusing on impacts to water quality and ecosystem services. Physicochemical data reveal that concentrations of heavy metals, nutrients, and organic pollutants regularly exceed World Health Organization (WHO) guidelines, with alarming levels of nitrate, phosphate, lead, chromium, and cadmium observed in both lakes. Agricultural runoff, industrial effluents, and untreated municipal wastewater emerge as primary pollution sources. These contaminants drive eutrophication, biodiversity loss, and the decline of fisheries, thereby undermining livelihoods and exacerbating water insecurity. Invasive species such as water hyacinth further degrade aquatic habitats, while sedimentation alters hydrological dynamics. The review highlights the flowing impacts of pollution on ecosystem services, including disruption of water supply, economic loss, and health risks. It also identifies knowledge gaps and emphasizes the need for integrated watershed governance, investment in wastewater treatment technologies, adoption of sustainable agricultural practices, and enhanced community participation. The review underscores the urgency of adopting a multisectoral response grounded in Integrated Water Resources Management (IWRM), emphasizing collaborative governance, technological innovation, and community-led stewardship as pathways to restore and sustain the health and services of lake ecosystems in the CRV.