Search Results (2,262)

Accurate identification of HMs contamination in mine tailings is essential for understanding pollution and supporting remediation. However, conventional laboratory monitoring is labor-intensive, time-consuming, and spatially discontinuous, while UAV hyperspectral inversion is limited by spectral inconsistency, unstable performance under small-sample conditions, and insufficient interpretability. Here, we developed an interpretable UAV–laboratory synergistic framework for Cd and Pb mapping in the Yitong open-pit mine. Forty site-level soil samples, composited from 200 subsamples, were linked with UAV hyperspectral observations. Direct Standardization was used to harmonize UAV and laboratory spectra. A weighted voting ensemble (RF, GBDT, and XGBoost) achieved the best performance (R² = 0.85), outperforming the individual models and showing slightly higher stability than CNN (R² = 0.84). Environmental covariates (pH, SOM, SMC) revealed distinct metal-specific prediction patterns: Cd was mainly associated with pH–SOM interactions, whereas Pb was more strongly associated with SOM–SMC coupling. SHAP and Grad-CAM identified sensitive spectral regions, with Cd linked to the 440–580 nm range and Pb to the 720–740 nm range. Overall, this study provides an integrated framework that combines spectral transfer correction, stable multi-model inversion, and mechanism-oriented interpretability for HMs monitoring in complex mining environments. Full article

Heavy metal pollution from coal gangue severely degrades mine soil structure and threatens landscape ecological stability. Particularly, γ-polyglutamic acid (γ-PGA), a green biopolymer, offers potential applications for pollution remediation while supporting ecological restoration. To evaluate γ-PGA’s efficacy in immobilizing Pb, Cd, and Zn in gangue-based soil and clarify its regulatory mechanism for landscape-friendly remediation, soil samples from a 3-year-weathered gangue hill in the Liupanshui mining area were subjected to indoor leaching experiments with different γ-PGA doses, combined with material characterization and Density Functional Theory (DFT) simulations. The results showed that the optimal γ-PGA dose was 6 g/kg, achieving 93.25% Pb immobilization and reducing Cd/Zn migration risk by over 30%; γ-PGA acted via carboxyl-amide dual-site chelation and hydrogen-bonded agglomeration, forming stable aggregates that inhibited metal migration. DFT calculations confirmed strong chelation for Cu²⁺ (−59.54 kcal/mol, BSSE-corrected: −57.23 kcal/mol), while Pb²⁺ and Cd²⁺ showed weaker binding (−8.32 kcal/mol and −5.67 kcal/mol, BSSE-corrected: −6.15 kcal/mol and −3.89 kcal/mol, respectively), indicating multi-pathway immobilization mechanisms. This study provides a theoretical basis for applying γ-PGA in mine landscape ecological restoration. Full article

Heavy metal contamination in soil and the resulting groundwater pollution are common at many brownfield sites. Soil washing, which dissolves contaminants into a washing solution to separate them from the soil matrix, has emerged as a promising remediation strategy. This study assessed the feasibility of applying soil washing to Pb-contaminated soil collected from an industrial area within the Trieste Port Authority (Italy) through a series of leaching tests. Batch tests were conducted using ethylenediaminetetraacetic acid (EDTA)-based extractants combined with various reducing agents to identify the most effective and environmentally sustainable washing solution. The results show that coupling EDTA with hydroxylamine hydrochloride or sodium dithionite significantly enhanced Pb solubilisation compared with EDTA alone, with dithionite emerging as the most suitable reducing agent due to its lower toxicity and reduced environmental impact. Sequential extraction tests revealed that up to 50% of total Pb could be removed after repeated washing cycles. Column leaching tests further confirmed the high efficiency of the EDTA–sodium dithionite system, achieving Pb removal rates of approximately 70% under continuous flow conditions. Overall, the results demonstrate that EDTA combined with low-dose sodium dithionite provides an effective and practical remediation strategy for heavily polluted industrial soils. Full article

Cadmium (Cd) and lead (Pb) co-contamination in construction and demolition waste landfill soils presents a significant challenge to ecosystem health, necessitating effective remediation strategies. This study investigated a synergistic approach combining a composite amendment (compost, superphosphate, desulfurized gypsum) with seven plant species to elucidate the interactions driving metal immobilization and phytoextraction. The amendment significantly altered soil properties: it reduced total Cd while increasing its bioavailability, and enhanced soil fertility (e.g., elevated organic matter and total nitrogen). Plant responses varied: Solanum americanum Mill. and Tagetes patula L. exhibited high Cd phytoextraction capacity, whereas Lolium perenne L. sequestered Cd/Pb primarily in roots. The bacterial community shifted from an oligotrophic, stress-tolerant state (e.g., Sphingomonas-dominated) in contaminated soil to a copiotrophic, functionally active state (e.g., Streptomyces-enriched) in amended soil. Community structure was strongly correlated with available Cd, pH, and nutrient levels. Key microbial biomarkers were specifically enriched in different plant rhizospheres. In contrast, the fungal community exhibited minimal responsiveness. These findings demonstrate that remediation efficiency is governed by an integrated “amendment–plant–microbe” framework: amendments regulate metal bioavailability, plants execute extraction or stabilization, and the restructured microbiome supports nutrient cycling and plant health. This integrated remediation strategy directly supports the Sustainable Development Goals of the 2030 Agenda, especially on environmentally sound management of chemicals and wastes and land degradation neutrality. This mechanistic understanding underscores the necessity of combined biological and chemical strategies for sustainable remediation of co-contaminated soils, ultimately enabling ecological reclamation and safe recycling of such urban marginal lands into productive uses. Full article

Heavy metals in the soil inhibit plant growth, which significantly reduce the crop yield and quality. Natural Resistance-Associated Macrophage Proteins (NRAMP) are widely distributed on the plasma and vacuolar membranes of plant roots, stems, and leaves. The NRAMP gene family plays a crucial role in modulating plant heavy-metal uptake, sequestration, distribution, and translocation, while the molecular evolution and mechanisms underlying these processes remain unclear. Here, we reviewed recent progress on plant NRAMP genes, focusing on their structural characteristics and functions in the absorption, transport, accumulation, and detoxification of various heavy metals. Furthermore, we performed an evolutionary analysis of NRAMP in green plants, indicating expansion and tandem duplication in ferns. In addition, their key amino acid sequences and secondary structures were highly conserved across plant species. The expression of diverse tissue showed that NRAMP genes displayed distinct spatial regulation in the leaves and roots. We also explored the underlying molecular mechanisms and regulatory pathways by which NRAMP genes influence heavy metal uptake. Therefore, by integrating structural conservation, molecular evolution, tissue- and single-cell expression patterns, ion-stress-responsive expression, regulatory pathways, and the Cd–Mn nutrient–toxin trade-off, this review provides a framework for identifying unresolved NRAMP functions and for guiding future strategies in low-heavy-metal crop breeding, metal homeostasis engineering, and phytoremediation. Full article

This paper presents a field case study of a mechanical failure that occurred in the bottom-hole assembly (BHA) during composite plug milling after hydraulic fracturing operations. The failure sequence was reconstructed using field hook load and torque records, operational documentation, and inspection of the damaged components recovered from the borehole. The results indicate that the critical condition developed progressively and was associated with increasing resistance to drill string movement, insufficient hole cleaning, and repeated attempts to continue milling and release the partially immobilized assembly. The observed damage pattern, together with the presence of residual cuttings and metallic debris in the borehole, supports the conclusion that the loss of the BHA section at the hydraulic safety sub resulted from the interaction of several adverse operational factors acting simultaneously, particularly the combined action of pull-up force and rotation under deteriorating borehole conditions. A supporting strength assessment of the hydraulic safety sub was used to relate characteristic operating points to the admissible working range of the connector. The study shows that hook load and torque data provide the greatest practical value when interpreted jointly and in their operational context rather than as isolated peak values. The findings support safer planning and execution of plug-milling and stuck-pipe remediation operations in highly deviated wells. Full article

This review focuses on research outputs of water purification, wastewater treatment, metallic remediation, and sorption-based experimental studies. It aims to identify the leading nations contributing to these areas and identify the journals that have published the highest number of papers from 2010 to 2025, and centers on yearly publication trends. A thorough quantitative analysis was carried out to examine key characteristics of adsorbents derived from various materials, as well as symmetry and asymmetry of wastewater treatment for the removal of metallic pollutants. Key adsorption mechanisms—including ion exchange, surface complexation, electrostatic attraction, and pore filling—are discussed alongside the structural roles of symmetric (ordered) and asymmetric (heterogeneous) adsorbent architectures. Data was collected from the Scopus database, focusing on specific keywords like “metal,” “water,” “removal,” “adsorption,” “purification,” “drinking water,” “nano adsorbent,” etc. Among approximately 29,598 publications encompassing research papers, reviews, short communications, conference papers, and book chapters, China emerged as the leading publisher with 11,957 papers, trailed by India (4324 papers), the USA (1825 papers), Iran (1739 papers), Saudi Arabia (1484 papers), Egypt (1318 papers), and Republic of Korea (1194 papers). The bibliometric mapping of conventional adsorbents and nanomaterials used in sorption-based technologies was analyzed using VOSviewer, revealing major research clusters, research hotspots, networks, and evolutionary patterns in wastewater treatment and sorption-based water purification. This study indicates that several journals from Elsevier Ltd. and Springer Nature are leading the field with a large number of publications per year. The analysis reveals a consistent upward trend in the number of research publications in recent years. In sum, the bibliometric data provided highlights the growing relevance of these areas among academicians and acts as a catalyst for further research, motivating researchers to investigate new adsorbents or modifications that could improve adsorption performance while maintaining economic viability and efficiency. Full article

Augmenting aquaculture feeds with black soldier fly (Hermetia illucens L.) larvae is an emerging solution to the industry’s fishmeal and fish oil dependence. However, the larva’s nutritional plasticity often results in bioaccumulation of metals from the rearing substrates. Larvae can be nutritionally enriched with microalgae, but research investigating growth impacts and metals uptake are lacking. In this study, a Stichococcaceae algae strain that is used to phycoremediate effluent from commercial anaerobic digesters was investigated as a rearing substrate. Larvae were reared on chicken feed enriched with stepped ratios of algae and spent coffee grounds (a reference waste feed). Growth, survival and metals content (ICP-OES) were recorded when 10% of larvae were prepupal. Survival was >98.5% across all treatments with a trend of increased growth with microalgal inclusion, and no significant impact of metals on growth. Metals uptake as determined by a bioaccumulation factor was significantly lower in the highest algae treatment compared to the coffee-only treatment. Larvae consistently accumulated cadmium and lead whereas arsenic bioaccumulation was only observed in three treatments. Cadmium had the highest bioaccumulation factor (up to 4.06) and arsenic the lowest (down to 0.41). Larvae did not exceed current European Union maximum metal ions levels for inclusion into aquafeeds. These findings highlight the potential of using Stichococcaceae to enrich black soldier fly larvae, offering a dual sustainable solution for wastewater remediation and aquaculture feed provision. Full article

The emerging demand for water pollution control has driven a significant interest in advanced porous materials for sustainable and effective wastewater treatment technologies. Metal–organic frameworks (MOFs) have been employed as promising substrates due to their versatile properties, especially their high surface area, tunable properties, and chemical functionality. However, their practical applications are often limited by poor aqueous stability, instability during recovery, and high production costs. Lignocellulosic biomass (LCB) is an abundant, low-cost, and renewable resource, primarily composed of cellulose, hemicellulose, and lignin, offering a sustainable solution for these challenges. This review critically examines the recent advances in design and applications of LCB-MOF materials for wastewater remediation. Several synthesis strategies, including in situ growth, ex situ impregnation, and post-synthetic modification, are systematically discussed in relation to their significance in enhancing stability, recyclability, and dispersibility of MOFs. The key, structural, morphological, and physicochemical properties of these LCB-MOFs were analyzed, along with their performance in removing organic dyes and heavy metal ions. Current drawbacks in long-term stability, scalability, and real-world wastewater performance are highlighted. Overall, LCB-MOFs demonstrate a promising class of sustainable materials that align with the principles of the circular economy and green chemistry, making them ideal for next-generation wastewater remediation technologies. Full article

Sustainable management of industrial solid waste is critical for a circular economy. This study presents a novel approach for valorizing blast furnace slag (BFS) into NaA zeolite through selective acetic acid leaching followed by hydrothermal crystallization. The leaching step selectively extracts Ca²⁺ and Mg²⁺ while efficiently retaining silicon and aluminum in the solid residue, producing a reactive aluminosilicate precursor that facilitates zeolite nucleation and growth. The effects of the silicon-to-aluminum molar ratio (n(Si)/n(Al)), crystallization temperature, and duration on the phase evolution and morphology were systematically investigated. The results demonstrate that phase-pure NaA zeolite with high crystallinity and a uniform cubic morphology can be obtained from precursor gels with n(Si)/n(Al) ratios of 0.5–1.25. Optimal synthesis conditions were identified as n(Na):n(Si):n(Al):n(H₂O) = 6:1:1:240 at 373 K for 8 h. The resulting zeolites exhibit a BET specific surface area of 52.1 m²/g, a micropore volume of 0.016 cm³/g, an average adsorption pore size of 4.7 nm, and an external specific surface area of 12.8 m²/g. It achieved near-complete removal of Cu²⁺ and high adsorption efficiencies for Pb²⁺ (77.78%) and Ni²⁺ (71.79%) from 250 mg/L solutions at 298 K with a dosage of 4.0 g/L, following the affinity sequence Cu²⁺ > Pb²⁺ > Ni²⁺, with all pairwise differences statistically significant at p < 0.001, using one-way ANOVA and Tukey’s HSD tests. The adsorption of three metal ions was most accurately described by the Freundlich isotherm and pseudo-second-order kinetic models, indicating heterogeneous multilayer chemisorption. The theoretical maximum monolayer adsorption capacities (q_max) were 307.67 mg/g for Cu²⁺, 246.09 mg/g for Pb²⁺, and 173.79 mg/g for Ni²⁺, whereas the kinetic equilibrium adsorption capacities (q_e) reached 62.69, 48.85 and 41.69 mg/g, respectively. This study demonstrates a value-added strategy for valorizing BFS into a micro-mesoporous adsorbent, advancing both circular resource utilization and environmental remediation. Full article

Ternary heterojunction photocatalysts enhance the separation and transport of photogenerated charge carriers, thereby boosting their redox activity for use in environmental and sustainable energy applications. This study focuses on the synthesis of a TiO₂/Bi₂O₃/g-C₃N₄ heterojunction composite via a ceramic method with TiO₂ loadings of 80%, 85%, and 90% (denoted 80T-BC, 85T-BC, and 90T-BC, respectively) to investigate structure–property–performance relationships in photocatalytic dye degradation. The structural, optical, and morphological properties of the synthesised materials were characterised using X-ray diffraction (XRD), scanning electron microscopy (SEM), and diffuse reflectance UV–Vis spectroscopy (DRS). The photocatalytic performance was evaluated by measuring the degradation of Rhodamine B under visible light irradiation. Under optimised conditions (pH 6, initial RhB concentration of 5 mg/L, and a reaction time of 120 min), a degradation rate of 99% was achieved. Furthermore, the semiconductor demonstrated significant antibacterial activity against both Gram-negative (Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacteria. This study presents a promising strategy for modifying TiO₂-based semiconductors by incorporating different metal oxides. The formation of the resulting heterojunction significantly enhances photocatalytic efficiency, demonstrating strong potential for practical environmental remediation. Full article

Heavy metal contamination in soils threatens ecosystem stability, agricultural productivity, and human health due to its persistence, toxicity, and ecological risks. Microbial remediation has emerged as a sustainable and cost-effective strategy, but the knowledge structure and research trends in this field remain insufficiently summarized. This study conducted a bibliometric analysis of publications on microbial remediation of heavy metal-contaminated soils retrieved from the Web of Science Core Collection from 2000 to 2025. VOSviewer (version 1.6.20), CiteSpace (version 7.0.R0), and the bibliometrix package (version 4.5.0) were used to analyze publication trends, major contributors, influential journals, and keyword evolution. The results showed that the number of publications increased continuously, with rapid growth after 2020. China, India, and the United States were the leading contributors, while Poland, Spain, and the United States played important bridging roles in international collaboration. Ravi Naidu was the most cited author, and Journal of Hazardous Materials was the most productive journal. Keyword analysis revealed a shift from pollutant degradation and microbial screening toward plant–microbe synergistic remediation, co-contaminated soil treatment, microbial community responses, and ecological risk assessment. Future research should emphasize multi-omics-based mechanisms, long-term in situ applications, and integrated evaluation frameworks. Full article

Mycogenic nanomaterials, nanoparticles (NPs) biosynthesized through fungal enzymatic and metabolic activity, have emerged as a compelling alternative to chemically synthesized nanomaterials, offering fundamental biocompatibility, green production conditions, and biologically functional surface coatings. Fungi, acting as natural “nanofactories,” harness reductases, oxidoreductases, secreted proteins, and secondary metabolites to reduce metal ions into stable NPs under ambient conditions, simultaneously capping the particles with biomolecules that enhance colloidal stability, biocompatibility, and secondary biological activity. Unlike previous reviews that have addressed either biosynthesis mechanisms or applications in isolation, this review uniquely adopts a structured “Promise vs. Barrier” framework across six interconnected thematic pillars, offering the first comprehensive critical synthesis that simultaneously maps mechanistic frontiers, biodiversity gaps, and translational barriers within mycogenic nanotechnology. The present review critically examines both the extraordinary promise and the persistent barriers facing mycogenic nanotechnology across biosynthetic mechanisms, fungal biodiversity, nanomaterial portfolio expansion, biomedical applications, environmental and agricultural utility, and industrial scalability. We highlight how emerging multiomics approaches, integrating transcriptomics, proteomics, and metabolomics, are beginning to decode the molecular blueprints of fungal NP synthesis, while acknowledging that mechanistic knowledge gaps, limited genetic toolkits for non-model fungi, and the absence of standardized protocols continue to impede progress. The fungal kingdom represents a vast, underexplored reservoir of nanofactory potential, with fewer than 1% of known species evaluated to date; strategic bioprospecting using genome mining and machine learning is beginning to unlock this diversity. Mycogenic NPs demonstrate broad-spectrum antimicrobial activity against multidrug-resistant pathogens, selective anticancer activity, biosensing capacity, and applications in wound healing, sustainable agriculture, environmental remediation, and smart food packaging. However, critical deficits persist in clinical validation, long-term toxicity data, manufacturing reproducibility, and regulatory clarity. The review concludes with a tiered roadmap, spanning immediate mechanistic priorities through to long-term synthetic biology and AI-integrated commercialization, and calls for coordinated international action on standardization, reference material development, and harmonized regulatory frameworks to bridge the gap between laboratory promise and real-world application. Full article

Heavy metal pollution remains a major global environmental challenge due to persistent ecological risks and potential threats to food safety. Microbial remediation and phytoremediation represent sustainable alternatives to conventional treatments; however, their effectiveness is strongly influenced by number of factors including nutrient availability. This review critically examines how nutritional regulation governs microbial metabolism, plant physiological responses, and rhizosphere interactions to enhance heavy metal transformation and removal. Metal bioavailability depends on type, concentration, soil pH, redox potential, and microbial processes. Interventions including fertilizers, chelating agents, inoculation with arbuscular mycorrhizal fungi and plant-growth-promoting rhizobacteria enhance phytoremediation processes through regulating plant nutrient and heavy metal uptake, while selection between ammonium/nitrate changes rhizosphere pH consequently affects plant metal uptake. Similarly, nutrients, i.e., phosphate, iron, zinc and manganese competitively affect metal uptake. Organic amendments enhance phytostabilization, especially for selenium and mercury, while enhancing chromium reduction. Sulfur-reducing bacteria precipitate metals as insoluble sulfides with 90% efficiency. In addition, soil amendments including plant-growth-promoting rhizobacteria, arbuscular mycorrhizal fungi, and metal-chelating agents can be strategically used to enhance the phytoextraction from metal from contaminated soils. We suggest that the future integration of modern approaches such as multi-omics and cisgenesis supported by artificial intelligence tools can help to accurately predict the efficiency of nutrient regulation strategies and their remediation outcomes, thereby supporting evidence-based soil management. Full article

Biological invasions and environmental pollution are the two primary threats facing contemporary agricultural ecosystems, and their interaction exacerbates agroecological risks and undermines agricultural sustainability. This study was conducted to systematically elucidate how heavy metals (HMs) and microplastics (MPs) alter the relative advantages of invasive plants in ecosystems, clarify the ecological processes involved, and propose recommendations for the protection of farmland ecosystems. The main conclusions are as follows: (1) Pollution acts as an environmental filter that negatively affects native species, including crops, while creating relative advantages for invasive plants with high tolerance and adaptive physiological mechanisms. (2) Pollution stress enables invasive plants to gain a competitive advantage over native plants through highly plastic resource allocation strategies, prioritization of growth, and more powerful allelopathic effects. (3) Pollution systematically amplifies the advantage of invasive plants by altering the strength of plant–soil feedback (PSF) and driving the restructuring of rhizosphere microbial communities. (4) Invasive plants can be used to produce biochar, which can then be applied in farmland ecosystems for the control of invasive plants and remediation of soil pollution. The framework constructed in this study indicates that heavy metal and microplastic pollution may enhance the invasion of alien plants, posing a serious threat to agroecosystem health and food security. However, using invasive plants as feedstock to produce biochar may offer a solution to the intertwined challenges of plant invasion and environmental pollution. Full article