Search Results (776)

The sources of potentially toxic elements (PTEs) in the lower reaches of the Yellow River (LYR) remain poorly understood due to intensive human activities in this region. To elucidate the spatiotemporal distribution characteristics and sources of PTEs, water samples were collected from both mainstream and tributary sites during the dry season (DS) and flood season (FS). Concentrations of eight PTEs (Fe, Mn, Cu, Zn, Pb, As, Cr, and Hg) were determined. The single-factor pollution index, Nemerow comprehensive pollution index, statistical techniques, and the positive matrix factorization (PMF) receptor model were jointly employed to evaluate PTEs pollution levels and quantitatively apportion its sources. The results showed that PTEs concentrations in the mainstream were significantly higher than those in the tributaries, with Fe and Mn being the primary contaminants exceeding standards. During the DS, the mean concentrations of Fe and Mn were 1.33 mg/L and 0.34 mg/L, with exceedance rates of 100% and 84.2%, respectively. In contrast, both concentrations declined markedly in the FS (Fe: 0.27 mg/L; Mn: 0.112 mg/L). The PMF model identified three sources in the DS, with contribution rates of 42.1% (geogenic background and domestic sewage), 32.4% (industrial wastewater), and 25.5% (agricultural sources). In the FS, two sources were resolved, namely a mixture of non-point source pollution and domestic sewage (64.3%) and a mixture of geogenic background and industrial wastewater (35.7%). The pronounced increase in non-point source contribution during the FS highlights the role of rainfall runoff in driving pollutant input. This study provides a scientific basis for PTEs pollution control in the LYR. Full article

Despite their size, small wetlands play a vital role in maintaining ecosystem stability. To clarify the pollution levels as well as potential ecological and health risks of potentially toxic elements (PTEs) in small wetlands, 85 water samples were collected from small wetlands in the Baghrash Lake Basin (BLB) of China, and six PTEs (As, Cd, Cu, Hg, Pb, and Zn) were determined for their contents. The Nemerow integrated pollution index (NPI) was adopted to evaluate PTE pollution levels. The ecological risk index (RI) and USEPA health risk assessment model were further applied to quantify potential ecological and health risks of PTEs, respectively. The results revealed that PTEs in small wetlands showed a slight pollution level, with an average NPI value of 0.73. Meanwhile, the integrated ecological risk index of PTEs showed a low ecological risk level, with an average RI value of 23.041. Health risk assessment results demonstrated that the non-carcinogenic risk of PTEs in small wetlands remained at a negligible level, while the carcinogenic risk stayed within acceptable limits for both local population groups: children and adults. Among all detected PTEs, Hg was identified as the primary pollutant and major ecological risk factor, while As posed the highest relative potential health risk while overall risks remained acceptable. The findings of this study can provide a scientific basis for the environmental protection of small wetlands in the BLB. Full article

The agricultural and environmental application of Miscanthus × giganteus biomass ash (MBA) as a soil amendment requires a thorough assessment of its properties, nutrient potential, and associated risks. This study characterizes the elemental composition, pH, cation exchange capacity (CEC), and polycyclic aromatic hydrocarbons (PAHs) content of MBA in comparison with other common biomass ashes (crops, wood, and sewage sludge) referred to the international regulatory standards. The ash exhibits a strong alkaline pH (11.03), suggesting potential to improve soil pH in acid soils, but requires careful controlled application to prevent excessive alkalization. The main nutrients detected include K (5.54%), Ca (2.07%), Mg (0.37%), and P (0.86%), indicating its potential as a soil amendment, though long-term use may cause nutrient imbalances. Micronutrients such as Zn (240.67 mg·kg⁻¹), Mn (297 mg·kg⁻¹), and Cu (33.5 mg·kg⁻¹) are found in concentrations suitable for agricultural use, while potentially toxic elements (PTEs), including Cd, Cr, Ni, and Pb, are below detection limits, thereby reducing the risk of pollution. As (8.3 mg·kg⁻¹) and ΣPAHs (1.63 mg·kg⁻¹) remain within safety thresholds, suggesting a low environmental toxicity of MBA. The low Na content (0.12%) indicates a minimal risk of salinity accumulation, distinguishing MBA from high-sodium biomass ashes. Soil alkalization, disruptions in nutrient balance, and element leaching are risks to be considered. Despite these concerns, its composition is in agreement with established safety guidelines, supporting its feasibility for valorization as a sustainable soil amendment and remediation material. To maximize agronomic benefits and mitigate environmental risks, it is important to utilize the ash, considering site conditions and carry out regular monitoring of the soil. Full article

As an important port in the Beibu Gulf of the South China Sea, Tieshangang Bay is potentially at risk of PTE pollution, yet systematic research integrating multi-hydrological period data remains limited. By applying pollution indices (C_f, WQI, I_geo, RI) combined with PCA, and PMF, we investigated PTE distribution characteristics, risk assessment, and source apportionment across different hydrological seasons. The results indicate that average PTE concentrations in surface seawater meet Class II standards of the Sea Water Quality Standard, with Zn and As showing relatively high concentrations compared to other PTEs. High-concentration areas were mainly located in the inner and middle bay. In sediments, concentrations of Zn and Cr were relatively high, with values generally higher inside the bay than outside. Both C_f and WQI values for seawater PTEs were below 1, indicating an overall low pollution risk. However, Cd and Hg in sediments presented a moderate potential ecological risk. Source apportionment revealed that seawater PTEs primarily originated from an industrial–aquaculture composite source (44.60%), while sediment PTEs were mainly attributed to composite terrestrial inputs (53.16%). These findings provide a scientific basis for PTE pollution management and sustainable development in Tieshangang Bay. Full article

The growing share of intermittent renewable electricity has increased the need for long-duration storage in industrial energy systems. Meanwhile, many industrial processes still release recoverable low-grade waste heat. Introducing this heat into pumped thermal energy storage (PTES) can improve thermal integration, but industrial waste heat is often unsteady, and its temperature and mass flow fluctuations may disturb the charging process. This study investigates an air-based reverse Brayton PTES system assisted by an industrial hot-water waste heat stream of approximately 100 °C. A dynamic model was developed in Simulink/Simscape. The shaft speed is fixed at 3000 rpm, and a PID controller regulates the molten-salt flow rate to maintain the thermal storage temperature. The results show that increasing the waste heat temperature from 95 °C to 105 °C mainly changes the charging-side heat distribution. The waste heat utilization power increases from 36.0 MW to 37.9 MW, while the regenerator power decreases from 126.8 MW to 122.0 MW. The thermal storage power increases slightly from 117.0 MW to 119.0 MW, with the mechanical input fixed at 81.0 MW. The influence of waste heat temperature is concentrated near the low-temperature heat exchanger, regenerator, and turbine outlet. Under dynamic disturbances, faster temperature ramps increase short-term deviations, but the PID-based molten-salt flow regulation keeps the storage temperature close to 550 °C, indicating that the proposed control strategy can suppress moderate thermal disturbances during charging. When waste heat temperature and mass flow rate vary together, same-direction changes strengthen the disturbance, whereas opposite-direction changes partly offset it. These results clarify the disturbance propagation mechanism of fluctuating industrial waste heat in the PTES charging loop and provide a basis for the dynamic design and temperature-control strategy of waste-heat-assisted PTES systems. Full article

Objective: Hemispherotomy is an effective treatment for select forms of drug-resistant hemispheric epilepsy, including perinatal stroke, Rasmussen’s encephalitis, and Sturge–Weber syndrome. Post-traumatic epilepsy (PTE) has been reported to occur in ~10% of children following traumatic brain injury (TBI). TBI has not been extensively evaluated as an indication for hemispherotomy, as its effects are rarely unilateral. Here, we report the results from five pediatric cases of hemispherotomy for drug-resistant hemispheric PTE. Methods: A retrospective review was performed of all pediatric patients with drug-resistant PTE secondary to TBI who underwent hemispherotomy between 2018 and 2022 at the Children’s Hospital of Philadelphia (n = 5). All patients initially underwent craniectomy and subsequent cranioplasty due to TBI; criteria for hemispherotomy were met in the following years, leading to a recommendation for hemispherotomy at the epilepsy surgery conference. Clinical characteristics, seizure and functional outcomes, and postoperative complications were reviewed. Seizure outcomes were classified according to the Engel criteria. Results: Five children (median age: 8.3 years, range: 5.0–10.3 years) with drug-resistant PTE underwent lateral trans-sylvian hemispherotomy. TBI etiology included non-accidental trauma (n = 3) and motor vehicle accidents (n = 2). All patients exhibited Engel Class Ia seizure outcomes (median follow-up: 15 months, range: 5–39 months), with a reduction in anti-seizure medications from a median of five preoperatively to one postoperatively. No patient experienced re-operation. Neuropsychological outcomes were patient-specific, with most exhibiting a mix of gains and challenges after surgery. Conclusion: We demonstrate the use of hemispherotomy to treat drug-resistant, hemispheric PTE in five children, with excellent reduction in seizure frequency and mixed or improved neuropsychological outcomes. Full article

Areas where mining activities overlap with agricultural production may promote the mobilization of potentially toxic elements (PTEs) into soils and water resources, thereby creating exposure pathways for populations living or working in these environments. This study analyzes the concentration of PTEs in agricultural soils and irrigation water from Santa Rosa, southern Ecuador, and assesses the associated health risks for exposed agricultural workers. For this purpose, 35 soil samples were collected from farms and 12 water samples from the irrigation canal during the dry season of 2025. The concentration of PTEs in soil and water was determined using X-ray fluorescence (XRF) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. The PTE concentration in both matrices was compared with the maximum permissible limits (MPL) established by Ecuadorian regulations. Non-carcinogenic hazard indices ($\mathrm{H}\mathrm{I}$) and carcinogenic risk ($\mathrm{T}\mathrm{C}\mathrm{R}$) were estimated following the U.S. EPA methodology. In soil, As and Cr were the PTEs of greatest concern, exceeding the MPL in 93% of the samples and by up to 4.4 and 2.4 times, respectively, while in water, all PTEs were below the MPL. Non-carcinogenic risk was below the recommended limit for soil and water ($\mathrm{H}{\mathrm{I}}_{\mathrm{s}\mathrm{o}\mathrm{i}\mathrm{l}}$ = 3.00 × 10⁻² and $\mathrm{H}{\mathrm{I}}_{\mathrm{w}\mathrm{a}\mathrm{t}\mathrm{e}\mathrm{r}}$ = 2.00 × 10⁻³), with As as the dominant contributor. Cancer risk was tolerable in soil ($\mathrm{T}\mathrm{C}{\mathrm{R}}_{\mathrm{s}\mathrm{o}\mathrm{i}\mathrm{l}}$ = 4.34 × 10⁻⁵), while in water it remained at a low level ($\mathrm{T}\mathrm{C}{\mathrm{R}}_{\mathrm{w}\mathrm{a}\mathrm{t}\mathrm{e}\mathrm{r}}$ = 1.65 × 10⁻⁶). These findings identify As and Cr as priority contaminants and support targeted monitoring and source-control measures in mining-influenced agricultural areas. Overall, by integrating agricultural soil and irrigation water quality with an occupational health risk assessment in Santa Rosa, this study contributes evidence to support future research in mining–agriculture coexistence areas. Full article

To address the issues of low light absorption efficiency and limited temperature gradient distribution in conventional planar Ag₂Se-based photothermoelectric (PTE) detectors, this paper proposes a structured design strategy for the surface functional layer. Ag₂Se-based PTE detectors with periodic surface microstructure arrays were fabricated using photolithography, and the influence of surface structure on the device’s PTE response performance was systematically investigated. The results indicate that surface microstructures can enhance light absorption and localized photothermal conversion efficiency, thereby increasing the PTE output voltage. However, they also lengthen the thermal diffusion path and reduce the dynamic response speed. When the structural pitch is 6.7 um, the device exhibits optimal overall detection performance within the measured spectral range of 405–950 nm. Under irradiation at a wavelength of 950 nm and a laser power density of 120 mW/cm², the device achieved a voltage sensitivity of 0.14 mV/W. This study reveals the trade-off between enhancing the response performance and response speed of Ag₂Se-based PTE detectors through surface structural design, providing experimental evidence and design guidance for rationally optimizing device structural parameters and realizing room-temperature PTE detection. Full article

Source apportionment and the elucidation of driving mechanisms are essential for targeted soil pollution management. This study investigated surface soils across six towns in southern Shimen County, northwestern Hunan Province, where 662 samples were collected to determine the concentrations of As, Cd, Cr, Cu, Ni, Pb, and Zn. Multivariate statistics and the APCS-MLR receptor model were integrated to quantify pollution sources, while three machine learning models (RF, XGBoost, and LightGBM) were applied to identify key drivers of the spatial enrichment of Cd. Results showed that Cd was significantly enriched, with a mean concentration of 0.43 mg/kg (3.41 times the provincial background value). The mean concentrations of As, Cr, Cu, Ni, Pb and Zn were 11.97 mg/kg, 81.01 mg/kg, 24.15 mg/kg, 49.25 mg/kg, 29.56 mg/kg and 76.77 mg/kg, respectively, and these PTEs remained at normal background levels. Significant inter-element correlations indicated common sources. Three primary sources were quantified—natural parent material (43.83%), mining activities (30.99%), and mixed sources of coal mining and agricultural inputs (7.84%), with 17.34% attributed to unidentified mixed sources. Natural sources dominated the geogenic enrichment of Cd, Cu, Ni, Pb, and Zn; mining activities governed the accumulation of As, Cr, Cu, and Pb; a mixed source of coal mining and agricultural practices contributed substantially to Cd enrichment. Machine learning identified PM10, topography, strata, and soil type as dominant drivers, with their total feature importance reaching 70.05%. Among these factors, natural factors and anthropogenic factors accounted for 44.23% and 55.77% of the total feature importance, in turn revealing coupled natural–anthropogenic controls. This study establishes an integrated framework linking source apportionment and driver identification, providing scientific insights for potentially toxic elements (PTEs) control in analogous mining–agricultural regions. Full article

Soil contamination by heavy metals (HMs) [or potential toxic elements (PTEs)] poses serious risks to ecosystems and human health. Metals persist in the environment and can reach groundwater and freshwater as part of the food-chain. In soils, anthropogenic inputs dominate over geogenic sources. Metal mobility is strongly controlled by factors such as pH, mineralogy, and erosion processes that transport metal-bearing clay fractions. Wind and water can transport soil, mainly clay particles that can usually bind contaminants such as HMs. Using waste material is a tool suggested from the circular economy, so waste becomes a valuable resource. This study evaluates the immobilization efficiency of several heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn) using phosphate amendments—synthetic hydroxyapatite, phosphatic rock from Florida and Morocco—applied to a brownfield site. Heavy metal immobilization followed a two-step mechanism: first rapid surface complexation and secondly partial dissolution of hydroxyapatite and ion exchange with Ca, leading to the precipitation of metal-substituted hydroxyapatite phases. Synthetic hydroxyapatite generally shows the best efficiency, whereas phosphatic rocks were less effective but still provided a measurable immobilization. From a circular economy perspective, however, phosphatic rocks remain attractive due to their lower cost, availability, and waste-valorization potential. Full article

Soil vulnerability is commonly assessed using environmental indicators; however, the lack of systematic and continuous monitoring often leads to incomplete and fragmented data, particularly in surface coal mining areas affected by potentially toxic element (PTE) contamination. Existing studies mainly focus on impact assessment, with limited emphasis on structured decision-support frameworks for selecting optimal soil protection strategies. This study addresses this gap by proposing an integrated hybrid decision-making framework that combines the Analytic Hierarchy Process (AHP), Sustainability Balanced Scorecard (SBSC), and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). The main contribution lies in integrating strategic sustainability perspectives (SBSC) with quantitative multi-criteria methods (AHP and TOPSIS), enabling a transparent and consistent evaluation of soil protection strategies across environmental, economic, technical, and social dimensions. The framework was applied to the Kostolac mining and energy complex in Serbia as a representative case study, using data from the State of the Environment Report as the basis for expert evaluation. The results identify risk reduction and environmental effectiveness as the dominant criteria, while the Progressive Strategy (SBSC) achieved the highest ranking. Sensitivity analysis confirmed the robustness of the model. From a policy perspective, the findings support prioritizing sustainability-oriented and risk-reduction strategies in mining regulations and investment planning. Full article

Potentially toxic elements (PTE) are persistent contaminants in coastal systems and may accumulate in marine organisms, with relevance for both environmental monitoring and seafood safety assessment. This study provides an exploratory cross-biota assessment of Cd, Cr, Cu, Ni, and Pb in fishery resources from the Romanian Black Sea in 2024. The dataset included 24 composite samples and 120 analyte-level observations across bivalves, gastropods, pelagic fish, and demersal fish. Tissue concentrations were integrated with regulatory maximum levels, bioconcentration factors (BCF), biota–sediment accumulation factors (BSAF), and adult dietary risk indices, including estimated daily intake (EDI), target hazard quotient (THQ), and total target hazard quotient (TTHQ). Within the limits of this single-year dataset, Cd and Pb concentrations were generally higher in bivalves than in fish and gastropods, whereas Cr showed higher values in several fish samples, particularly pelagic fish. Cd was the main element of concern, with regulatory exceedances occurring mainly in bivalves and fewer exceedances in pelagic fish, while Pb exceedance was isolated. BCF and BSAF supported the relevance of Cd as a priority element but were interpreted only as descriptive tissue–water and tissue–sediment ratios, not as evidence of specific uptake pathways. Low abiotic Cd concentrations may have inflated some ratio-based values, and Cr interpretation remains limited by the absence of Cr speciation and dissolved/particulate partitioning data. The adult dietary risk assessment did not indicate substantial non-carcinogenic concern, as all individual THQ values and cumulative TTHQ values remained below 1. Overall, the findings support continued PTE monitoring in the Romanian Black Sea, using sessile bivalves as indicators of local environmental contamination and including gastropods and representative pelagic and demersal fish species of ecological and fisheries relevance to capture contaminant patterns across benthic and mobile fishery resources. Future monitoring should improve species-level replication, integrate metal partitioning in abiotic matrices, and include additional contaminants of seafood safety relevance, particularly Hg and As. Full article

Potentially toxic element (PTE) contamination in rice poses significant food safety risks, particularly in regions with intensive agriculture, industry, and traffic. This study provides a systematic assessment of the accumulation, translocation, sources, and health risks of PTEs (As, Cd, Cr, Cu, Ni, Pb, Zn) in the atmospheric deposition–soil–rice system across four distinct anthropogenic source areas (industrial, peri-urban, rural, and roadside areas) in Hunan Province, China. The rural area was categorized as clean. Industrial areas had the highest soil pollution index, while roadside areas recorded the highest atmospheric deposition flux of Pb (19.95 μg/m²/day) and As (1.93 μg/m²/day). Correspondingly, industrial areas exhibited the highest Cd (0.38 mg/kg) and Pb (0.94 mg/kg) in rice grains, whereas roadside areas showed the highest Pb (1.40 mg/kg) and As (2.99 mg/kg) in leaves. The findings indicated that rice in roadside areas primarily accumulate PTEs through foliar absorption of atmospheric deposition, whereas in industrial and peri-urban areas it was primarily through root uptake and translocation of PTEs to rice grains, particularly for Cd and Pb. Source apportionment identified natural, industrial, and traffic as the three primary sources. The Bayesian mixing model revealed that the natural source contributed the highest proportion to rice grains (48.3–70.6%) across all four source areas. Except for natural sources, industrial sources dominated in industrial areas (29.1%), traffic emissions prevailed in roadside areas (19.4%), while mixed sources had the highest proportion in peri-urban areas (28.4%). Health risk assessment revealed that the total hazard index followed the order of peri-urban > industrial > roadside > rural areas, with rice ingestion being the dominant exposure pathway, accounting for over 90% of the total risk. The primary contributors to health risks were identified as As, Cd, and Pb, particularly in industrial and peri-urban areas. These findings provide a scientific basis for developing region-specific mitigation strategies tailored to the dominant contamination pathways in each area. Full article

Early diagnosis of post-traumatic epilepsy (PTE) is crucial for timely intervention. However, it is hampered by the lack of reliable biomarkers. In this review, we provide a comprehensive summary of current advances in PTE biomarker research, drawing primarily on evidence from human cohort studies, with selective support from experimental animal models where mechanistic insights are required. We cover (i) neuroimaging, including CT, MRI, and EEG/qEEG, which reveal structural and functional alterations associated with epileptogenesis; (ii) molecular biomarkers, including RNAs, proteins, metabolites, and extracellular vesicle (EV)-derived molecules that reflect neuroinflammation, blood–brain barrier (BBB) dysfunction, neuronal injury, and synaptic remodeling; and (iii) artificial intelligence (AI)-assisted approaches, which integrate multimodal datasets to identify complex predictive patterns. While individual modalities offer valuable but incomplete prognostic information, AI-driven analytics hold the greatest promise for early predictive power by combining multimodal data. Future progress will depend on the integration of high-resolution imaging, multi-omics profiling, and rigorous validation to deliver clinically actionable biomarker panels and ultimately reduce the burden of PTE. Full article

Potentially toxic elements (PTE) pollution from lead–zinc (Pb–Zn) production poses significant ecological risks, requiring systematic assessment across the industrial chain. This study investigated soil, surface water, and sediments near a Pb–Zn mining area, integrating pollution indices (I_geo, NIPI, RI) with human health risk models. A spatial analysis framework was established by combining proportional symbol mapping and Thiessen polygons to analyze contamination patterns under small-sample conditions. Results showed a clear pollution hierarchy: smelting > beneficiation > tailings ≈ mining. Smelting and beneficiation zones exhibited multi-element pollution; Hazard Index (HI) exceedance probabilities reached 89% and 95%, respectively, while carcinogenic risk (CR) exceedance approached 100% across all zones. Cd was the dominant ecological risk factor, particularly in mining and tailings zones, where risk was mainly driven by a single element. Source apportionment identified two industrial groups—smelting-related (Pb, Hg, Zn, Se) and ore-associated (As, Cd, Cu, Sb)—whereas Cr, Ni, Co, and V were mainly derived from natural sources. These results indicate the need for coordinated management of beneficiation and smelting processes and provide a spatial analysis approach for small-sample assessment. Full article