Search Results (5,297)

The enrichment of cadmium (Cd) in farmland soil poses serious risks to agricultural safety and remains challenging to remediate. This study evaluated CaAl-layered double hydroxide (CaAl-LDH) as a highly efficient and stable passivator for Cd-contaminated soil. Laboratory adsorption tests demonstrated that Cd²⁺ adsorption on CaAl-LDH followed pseudo-second-order kinetics and the Langmuir model, indicating monolayer chemisorption, with a maximum capacity of 469.48 mg·g⁻¹ at pH 6. The adsorption mechanisms include surface complexation, interlayer anion exchange, dissolution–precipitation, and isomorphic substitution. A three-year field trial in Yongkang City, China showed that CaAl-LDH promoted the transformation of Cd in rhizosphere soil from the ion exchange state (F2) to the residual state (F7) and Fe–Mn oxidized state (F5), reducing the exchangeable Cd content by 26.71%. Consequently, Cd content in rice grains decreased by 68.42% in the first year and remained over 37% lower in the second year, consistently below the national food safety limit. Future research should focus on the optimization of material’s stability and application protocol. The results demonstrate that CaAl-LDH provides a cost-effective and sustainable strategy for the in situ passivation remediation of Cd-contaminated farmland, contributing to food safety and sustainable agriculture. Full article

Microplastics (MPs) are widespread contaminants in seabeds, where they are bioavailable to benthic organisms including polychaetes. Among them, the bearded fireworm represents a potential target for MP, given its opportunistic predatory and scavenging habits, reaching high densities and displaying a wide expansion range in the Mediterranean Sea. In this pilot bench-scale study, we investigated MP ingestion and egestion in this species through a simplified two-level trophic chain, using mussels as prey. Mediterranean mussels were first exposed to fluorescently labelled polystyrene microspheres (micro-PS, nominal size of 10 µm) and offered to fireworms. Within three days, fireworm faecal pellets, intestines, and body fluids were collected and digested to quantify MP. In-depth microscopy analyses were carried out to evaluate potential chemical and physical alterations of MPs during gut passage. Minimal retention of MPs in fireworm tissues was observed, while faecal pellets contained substantial quantities of micro-PS. Despite most MPs exhibiting negligible chemical changes, they were covered by faecal matter and colonised by bacteria, with minor surface alterations. Our findings provide the first evidence of MP trophic transfer from a filter feeder to a carnivorous polychaete. The rapid excretion of MPs by bearded fireworms gives insights into polychaete-mediated MP fluxes and MP fate in benthic ecosystems. Full article

Crude oil exploration and transportation have led to significant soil contamination in nearby communities, yet seasonal and depth-related variations remain poorly understood. This study assessed physicochemical properties, potentially toxic elements, and polycyclic aromatic hydrocarbons in surface (0–15 cm) and subsurface (15–30 cm) soils from the Ibaa community and its pipeline Right of Way (ROW) in Rivers State, Nigeria. Samples were collected during wet and dry seasons from five locations, and analyses were conducted using standard methods. Results showed that soil temperature ranged from 27.5 to 31.2 °C, reflecting natural environmental conditions, while nitrate concentrations (1.23–3.45 mg/kg) and moisture content (14.3–23.9%) were within acceptable WHO limits. The pH values (4.61–5.72) suggested acidic conditions, particularly in the unremediated areas. Total Organic Carbon exceeded 3%, with a maximum of 6.23% recorded in the wet season, suggesting persistent hydrocarbon contamination. Phosphorus levels (2.65–6.02 mg/kg) were below the 15 mg/kg threshold. Notably, As (4.93 mg/kg) and Cd (1.67 mg/kg) concentrations exceeded the permissible WHO limits. Positive correlations were observed between As–Cd (r = 0.79), Cd–Cu (r = 0.85), and Pb–Cu (r = 0.64). Principal Component Analysis identified four components for physicochemical parameters (81.9% variance) and two for metals (82.6% variance), suggesting crude oil combustion and vehicular emissions as dominant pollution sources. Pb also correlated significantly with total PAHs in the dry season (r = 0.54, p < 0.05). The study highlights the influence of season and depth on contaminant behavior and emphasizes the urgent need for remediation and monitoring to mitigate ecological and public health risks. Full article

Heavy metal(loid) (HM) contamination in water arises from various anthropogenic activities and natural processes, posing risks to human health through ingestion and dermal absorption. Although numerous studies have assessed health risks associated with HMs in water, inconsistencies in the selection of exposure and toxicity factors limit comparability and reliability across studies. To address this gap, the aim of this review was to provide a comprehensive synthesis of exposure and toxicity factors used in health risk assessment (HRA) of HMs in water. The objectives were to evaluate the variability in ingestion, body weight, exposure duration and frequency, and dermal contact parameters, as well as in reference doses and cancer slope factors and to propose standardized values and statistical distributions for more consistent risk estimation. A systematic search of the Scopus database retrieved 806 studies, from which highly cited articles (≥100 citations) and recent publications (2023–2025) were prioritized for analysis. The findings revealed substantial variability in factors and showed that probabilistic approaches, particularly Monte Carlo simulation, were increasingly applied and provided more reliable estimates than traditional deterministic methods. The highest agreement was observed for exposure frequency for ingestion (365 days/year) and skin surface area (18,000 cm²), each applied in 75.5% of cases. By identifying inconsistencies in current practices and proposing standardized exposure and toxicity values and distributions for water, this review is expected to offer practical recommendations to improve the robustness, reliability, and comparability of HRAs, ultimately informing more effective policy-making and water management practices. Full article

Land Surface Temperature (LST) is a critical variable for understanding land–atmosphere interactions and is widely applied in urban heat monitoring, evapotranspiration estimation, near-surface air temperature modeling, soil moisture assessment, and climate studies. MODIS LST products, with their global coverage, long-term consistency, and radiometric calibration, are a major source of LST data. However, frequent data gaps caused by cloud contamination and atmospheric interference severely limit their applicability in analyses requiring high spatiotemporal continuity. This study presents a seamless MODIS LST reconstruction framework that integrates multi-source data fusion and a multi-stage optimization strategy. The method consists of three key components: (1) topography- and land cover-constrained spatial interpolation, which preliminarily fills orbit-induced gaps using elevation and land cover similarity criteria; (2) pixel-level LST reconstruction via random forest (RF) modeling with multi-source predictors (e.g., NDVI, NDWI, surface reflectance, DEM, land cover), coupled with HANTS-based temporal smoothing to enhance temporal consistency and seasonal fidelity; and (3) Poisson-based image fusion, which ensures spatial continuity and smooth transitions without compromising temperature gradients. Experiments conducted over two representative regions—Huainan and Jining—demonstrate the superior performance of the proposed method under both daytime and nighttime scenarios. The integrated approach (Step 3) achieves high accuracy, with correlation coefficients (CCs) exceeding 0.95 and root mean square errors (RMSEs) below 2K, outperforming conventional HANTS and standalone interpolation methods. Cross-validation with high-resolution Landsat LST further confirms the method’s ability to retain spatial detail and cross-scale consistency. Overall, this study offers a robust and generalizable solution for reconstructing MODIS LST with high spatial and temporal fidelity. The framework holds strong potential for broad applications in land surface process modeling, regional climate studies, and urban thermal environment analysis. Full article

The physical demands of overhead tasks can lead to musculoskeletal strain, particularly in scenarios requiring prolonged arm elevation such as in Chemical, Biological, Radiological, and Nuclear (CBRN) operations. To address this, an active shoulder exoskeleton was developed that is compatible with CBRN protective gear. The aim of this laboratory study was to assess the biomechanical and physiological effects of the system during upper limb tasks representative of real-world applications, without the use of protective suits. Twenty-two male participants performed two tasks with and without the exoskeleton: (1) 5 kg lifting task and (2) repetitive spraying tasks with a spray lance. Muscle activity of the m. anterior deltoid was measured using surface electromyography, while energy expenditure was assessed via spiroergometry. The exoskeleton significantly reduced muscular demands in the anterior deltoid, with a decrease of up to 40% during the spraying task and 29% percent during lifting task. Additionally, oxygen consumption per kilogram of body mass decreased by 6.5 to 8.2% across tasks. Participants reported lower fatigue and greater task manageability when using the exoskeleton, particularly for sustained and semi-static overhead postures. The results demonstrate that the exoskeleton effectively reduces workload during upper limb tasks. These findings support its application not only for soldiers in contaminated environments but also in industrial settings involving overhead work. Future research will need to validate these effects under realistic CBRN conditions to confirm operational compatibility. Full article

Encapsulation of lubricating agents has many advantages, as it helps to protect them from external factors, oxidation and degradation, can support their controlled and prolonged release, and also preserves the environment from accidental contamination with these substances. In our experiments various types of thermo-responsive, paraffin wax capsules capable of safely transporting liquid and semi-solid lubricants were designed, fabricated and tested. Lubricating oils were primarily encapsulated inside hemispherical wax shells closed with special caps, but also in wax spherocylinders and two-compartment structures. Greases were protected with wax coatings with the thickness ranging from 0.187 to 0.774 mm. The payload release from our core–shell capsules occurred not only due to the exerted mechanical force but also in a controlled manner upon prolonged contact with a heated surface. The wax shells of the capsules lying on the plate, whose temperature was increased at a rate of 0.025°C/s, began to melt gradually, starting from ≈55.5 °C. This temperature-triggered lubricant liberation can be useful when, for example, a machine element becomes excessively hot due to friction. The wax itself also has lubricating properties, so the crushed or melted coating cannot be treated as waste, but only as an additional factor supporting lubrication. The practical applications of our wax capsules were demonstrated with five examples. Full article

The photocatalytic efficiency of TiO₂ was significantly enhanced by coupling with WO₃ to form a TiO₂/WO₃ heterostructure, designed to operate effectively under UV-LED irradiation. The nanocomposites were synthesized via a hydrothermal route, and their activity was evaluated through the degradation of the pharmaceutical pollutant venlafaxine. Contaminants are rarely addressed in photocatalytic studies. Unlike a simple physical mixture of commercial TiO₂ and WO₃ powders, the hydrothermally synthesized TiO₂/WO₃ photocatalyst exhibited superior efficiency, attributable to its nanoscale dimensions achieved via the hydrothermal route, which promoted improved charge carrier separation, enhanced surface homogeneity, and the formation of an effective heterojunction interface. An optimization study varying the WO₃ content (5, 10, 20, and 30 wt.%) within the TiO₂ revealed that the 10 wt.% WO₃ composition achieved the highest performance, with ~52% venlafaxine degradation within 60 min. SEM, TEM, FTIR, Raman spectroscopy, XRD, and UV-Vis DRS revealed the successful incorporation of WO3 into the TiO₂ matrix, confirming phase purity and composition-dependent structural evolution of the nanocomposite, and evidencing extended light absorption and superior charge-transfer properties. Importantly, the optimized photocatalyst thin film retained excellent stability and reusability, maintaining high degradation efficiency over three consecutive cycles with negligible activity loss, which avoids slurry separation. These findings establish hydrothermally synthesized TiO₂/10%WO₃ thin film heterostructures as effective and sustainable photocatalytic platforms for the removal of pharmaceutical pollutants in wastewater under UV-LED irradiation. Full article

Microplastics (MPs), as an emerging persistent contaminant, pose a potential threat to ecosystems and human health. The adsorptive removal of MPs from aqueous environments using magnetic nanoparticles has become a particularly promising remediation technology. Nevertheless, there remain significant knowledge gaps regarding its adsorption mechanism, especially how the key physical properties of magnetic nanoparticles regulate their adsorption behavior towards MPs. This study first investigated the relationship between the particle size of Fe₃O₄ nanoparticles and their adsorption efficacy for MPs. The results demonstrated a non-monotonic, size-dependent adsorption of MPs by Fe₃O₄ nanoparticles, with the adsorption efficiency and capacity following the order: 300 nm > 15 nm > 100 nm. This non-linear relationship suggested that factors other than specific surface area (which would favor smaller particles) are significantly influencing the adsorption process. Isotherm analysis indicated that the adsorption is not an ideal monolayer coverage process. Kinetic studies showed that the adsorption process could be better described by the pseudo-second-order model, while intra-particle diffusion played a critical role throughout the adsorption process. Furthermore, the effect of pH on adsorption efficiency was examined, revealing that the optimal performance occurs under neutral to weak acidic conditions, which is consistent with measurements of surface charges of nanoparticles. These findings suggest that the adsorption is not determined by specific surface area but is dominated by electrostatic interactions. The size-dependent adsorption of MPs by Fe₃O₄ nanoparticles provides new insights for the modification of magnetic adsorbents and offers a novel perspective for the sustainable and efficient remediation of environmental MPs pollution. Full article

Access to clean water remains a global challenge, particularly in areas where populations rely on surface water. These water sources must be treated. Coagulation with chemicals causes environmental problems and adverse effects on human health. Natural coagulants obtained from papaya (Carica papaya) waste are presented as an alternative that is safe for human health, non-polluting, and biodegradable. The effectiveness of these natural coagulants is compared to that of aluminum sulfate using jar tests and synthetic and natural surface water, with statistical tools to model treatment processes. All coagulants have competitive results, reaching turbidity remotion levels above 90%. However, in equivalent tested ranges, natural coagulants require lower dosages and perform better with high initial water turbidity due to their polymeric bridging mechanisms and adsorption processes through the action of their functional groups, as detected by FTIR analysis. Additional testing with contaminated water from the Valsequillo dam confirms the use of these coagulants to treat water, with papaya seed coagulant yielding the best results and requiring lower doses, making it a competitive alternative. It can be concluded that papaya-based coagulants obtained from waste can be used as an eco-friendly alternative to aluminum sulfate in physicochemical treatments to purify surface water for human consumption. Full article

Metal contamination poses serious environmental and human health risks, which results in the need for low-cost remediation approaches. The utilization of agricultural byproducts for the removal of metal contaminants is considered cost-effective and environmentally sustainable. Garlic byproducts are rich in sulfur-containing compounds, and various functional groups contribute to metal binding. This study aimed to evaluate the potential of garlic stem and peel for the removal of cadmium (Cd), lead (Pb), and arsenic (As) from aqueous solutions and for their immobilization in contaminated soils. Batch sorption experiments conducted at pH 7 for 24 h showed that garlic stem removed 71.5% of Cd and 70.8% of Pb, while garlic peel achieved 65.4% and 79.4% removal, respectively. The higher Pb removal by garlic peel might be attributed to its higher sulfur content. However, both byproducts were less effective in removing As(III) and showed negligible removal of As(V), as these species predominantly occur in neutral or negatively charged species at neutral pH, resulting in weak interactions with negatively charged surface functional groups. Soil incubation experiments were conducted using 1% and 5% amendments of garlic stem and peel in Pb- and As-contaminated soils. Extractable Pb concentrations significantly increased in soils treated with 1% garlic peel because of the formation of labile complexes of Pb with dissolved organic carbon. However, a column experiment to evaluate the impact on Pb mobility under saturated and unsaturated conditions showed that Pb concentration in soil pore water decreased with garlic stem. Pb concentration was lower under saturated conditions, possibly due to the precipitation of Pb as PbS. Although the short-term application of raw agricultural byproducts increased extractable metal concentrations, long-term incubation reduced Pb levels in pore water. These findings suggest that unmodified garlic stem is a promising, cost-effective amendment for Pb immobilization in soil. Nevertheless, caution is needed in its application to prevent unintended metal mobilization in soil. Full article

Sugarcane juice (SJ) is a naturally sweet beverage rich in sucrose but prone to microbial contamination, raising concerns among health-conscious consumers. This study aimed to develop a functional SJ enriched with fructooligosaccharides (FOS) using enzymatic treatment, followed by high-pressure processing (HPP) to enhance its safety and quality. The enzymatic conversion of sucrose to FOS was achieved using Pectinex^® Ultra SP-L (commercial enzyme), with varying enzyme concentrations, temperatures and incubation times to identify the optimal conditions via response surface methodology (RSM). Under optimal conditions (1000 U/g enzyme concentration, 48 °C, 13 h), sucrose in raw SJ (124.33 g/L) decreased by 59.17 g/L, resulting in maximum reducing sugars (16.02 ± 0.58 g/L) and enhanced FOS yields, notably kestose (2.37 g/L) and nystose (9.35 g/L). After being treated with HPP at 600 MPa for 3 min, E. coli K12 and L. innocua were effectively inactivated by achieving > 5 log reduction, meeting USFDA standards. Furthermore, it was also observed that HPP could reduce yeast (6.56 × 10² CFU/mL). Meanwhile, mold, E. coli, and coliforms were not detected. Additionally, HPP maintained the juice’s physicochemical properties, outperforming thermal pasteurization (85 °C for 10 min) in quality preservation. This study highlights the potential of enzymatic treatment and HPP in improving SJ safety and functionality. Full article

In coastal hot and humid regions, the steel pin of AC porcelain insulators often suffers from severe electrochemical corrosion due to surface contamination and moisture, leading to insulator string breakage. Contrary to the common belief that AC corrosion is negligible, this study reveals the significant role of the DC component in leakage currents and the synergy of this DC component with localized high current densities in accelerating corrosion, based on field investigations and experiments. Using a simulation model based on the Suwarno equivalent circuit, it is shown that non-linear contamination causes highly non-sinusoidal leakage currents, with total harmonic distortion up to 40% and a DC component of approximately 22%. To mitigate this, a conductive silicone rubber coating is proposed to block moisture and distribute leakage current evenly, keeping surface current density below the critical threshold of 100 A/m². Simulations indicate that a 2 mm thick coating with conductivity around 10⁻⁴ S/m effectively reduces current density to a safe level. Accelerated corrosion tests confirm that this conductive coating significantly suppresses pitting corrosion caused by high current densities, outperforming traditional insulating coatings. This study presents a practical and effective approach for protecting AC insulators in harsh environments, contributing to improved transmission line reliability in high-temperature and high-humidity regions. Full article

Norovirus (NoV) is a symptomatic virus that is the leading cause of gastrointestinal disease. It spreads easily through the fecal–oral route and contact with contaminated food or surfaces. Maintaining a high level of hygiene in food industry settings and refocusing food production on isolating and testing natural compounds that exhibit antimicrobial and antioxidant properties are important elements in preventing NoVs infection. This study evaluated plant extracts prepared by cold brew and cold concentrate techniques for their antioxidant and antiviral activity. The extracts obtained demonstrated high antioxidant activity, with notable variation depending on the plant material, ranging from moderate to very strong levels. Correspondingly, high antiviral potential was observed, reaching the nearly complete inactivation of the virus. Remarkably, the highest virucidal effects were already achieved at relatively elevated, but not maximal, antioxidant activity levels. The results of the study indicate that cold water extraction techniques allow for the obtention of plant extracts showing strong virus-inactivating activity and favorable antioxidant activity. Full article

Soil contamination with heavy metals (HM) poses a risk to human health and can impact different soil functions. This study aimed to determine the influence of heavy metal pollution on the physical and physicochemical characteristics of the two profiles of alluvial–deluvial soil under grassland located at different distances from the Aurubis-Pirdop Copper smelter in Bulgaria. Data for soil particle-size distribution, soil bulk and particle densities, mineralogical composition, soil organic carbon contents, cation exchange properties, surface charge, soil water retention curves, pore size distribution—obtained by mercury intrusion porosimetry (MIP)—and thermal properties were obtained. The contents of Pb, Cu, As, Zn, and Cd were above the maximum permissible level in the humic horizon and decreased with depth and distance from the Copper smelter. Depending on HM speciation, the correlations are established with SOC and most physicochemical parameters. It can be concluded that the HMs impact the clay content, specific surface area, distribution of pores, and the water stability of soil aggregate fraction 1–3 mm to varying degrees. Full article