Search Results (2,799)

Increased soil metal concentrations may be detrimental to human health as well as the environment. This study was conducted to infer the potential environmental risks and possible sources of heavy metal pollution in serpentine soils in Alacakaya. For this purpose, the concentrations of Ni, Co, Zn, Pb, Cu, As, and Cr in 28 soil samples collected from serpentine soils in the region were determined using ICP-MS. The heavy metal pollution of soils in the region was examined by applying different indicators, and the pollution load index (PLI), contamination factor (CF) and geo-accumulation index (Igeo) were used to assess ecological risks. The average concentrations of metals were in the order of Ni (2003) > Cu (1220) > Cr (823) > Zn (206) > Co (159) > Pb (56.9) > As (38.9) mg kg⁻¹. The arsenic (As) concentration exceeded the limits permitted by the World Health Organization (WHO) in 53.6% of the soil samples, the zinc (Zn) concentration in 35.7%; the lead (Pb) concentration in 14.3%; and the Ni, Co, Cr, and Cu concentrations in 100% of the samples. The average Igeos were as follows: As 3.28 (heavily polluted); Cu, 3.23 (heavily polluted); Pb 1.04 (moderately polluted); Zn 0.71 (lightly polluted); Ni, 4.04 (heavily to extremely polluted); and Co 2.03 and Cr 2.35 (moderately to heavily polluted). According to Igeo values, it was stated that Ni, As, Cu, Cr and Co were the elements that posed the greatest ecological risk in the study area. According to the CF values, pollution is observed in all samples, and there is very serious Ni pollution. The heavy metals showing the most pollution were Cu > As > Cr > Co > Pb > Zn. Samples from the study area demonstrate strongly contaminated soil based on the PLI (mean 7.4) values. These findings provide important information for soil remediation and the removal of heavy metal contamination from soils in similar regions. Full article

Thallium (Tl) and cadmium (Cd) are highly toxic heavy metals that frequently co-occur in sulfide ores, posing a serious food safety risk through accumulation in rice. Although calcium-based (Ca-based) amendments have been widely applied to remediate heavy metal-contaminated soils, their effectiveness in Tl–Cd co-contaminated paddy soils remains unclear. A pot experiment was conducted to evaluate four Ca-based amendments—limestone powder, dolomite powder, hydrated lime, and oyster shell powder—on Tl and Cd bioavailability and uptake in paddy soil near a mining area. Ca-based amendments effectively reduced Tl and Cd bioavailability, with DTPA-Tl reducing by 11.2–17.2% and DTPA-Cd by 8.9–21.3%. These reductions were attributed to increased soil pH and decreased DOC, Fe, and Mn in the pore water. Additionally, Ca-based amendments shifted Tl and Cd from acid-extractable to residual fractions, reducing mobility. Additionally, Ca-based amendments promoted Fe/Mn plaque formation on rice roots, reducing Tl and Cd uptake. Consequently, Tl and Cd concentrations in brown rice decreased by over 14%, with the lowest levels observed under oyster shell powder. However, Cd concentrations still exceeded the maximum permissible limit, indicating that, although Ca-based amendments show considerable potential for in situ remediation of Tl–Cd co-contaminated paddy soils, further optimization and additional measures are required to achieve safe production. Full article

Explosive ordnance (EO), including AXO (abandoned explosive ordnance), IEDs (improvised explosives devices), and UXO (unexploded ordnance), are widely recognised for their blast and fragmentation hazards, but they also represent a persistent and under-addressed source of occupational chemical exposure for explosive ordnance disposal (EOD) personnel. EOD core activities liberate mixed metals and energetic chemicals, resulting in exposures that are multi-route (inhalation of dusts and fumes, dermal loading amplified by sweat and glove occlusion, and ingestion via hand-to-mouth transfer during eating, drinking, or smoking) and multi-temporal (repeated low-dose background plus task-driven spikes), as well as chemically complex. Clinically, this can present as syndromic overlap across acute and chronic domains, with symptoms that are easily misattributed to heat stress, dehydration, infection, or fatigue. Acute effects of concern include neurotoxic presentations (headache, dizziness, confusion, tremor, and seizure), respiratory and mucosal irritation following dust or fume events, gastrointestinal symptoms, and patterns suggestive of acute hepatic or renal stress, particularly when high-intensity tasks occur in hot environments that compound physiologic strain. Chronic outcomes relevant to repeatedly exposed EOD personnel include renal function decline, neurocognitive effects that can degrade operational decision making and safety, persistent haematologic abnormalities, and endocrine disruption signals, with long-latency risks requiring cautious interpretation given sparse longitudinal data and confounding co-exposures. This review synthesises the current evidence base through an EOD lens and translates it into pragmatic clinical and programmatic actions: task-based exposure characterisation; tiered biomonitoring and medical surveillance aligned to operational tempo; incident-triggered assessment pathways after high-residue events; and prevention strategies that work under field constraints, including contamination control zones, hygiene enforcement, glove and respiratory protection optimisation, tool and vehicle decontamination, and measures to prevent secondary transfer and take-home exposure. The central takeaway is practical: EOD programs can reduce morbidity and improve readiness by treating explosive ordnance as a chemical mixture exposure problem, adopting mixture-aware clinical triage, and embedding surveillance and controls that match how EOD work is actually performed. Full article

Nickel-rich NMC-811 is a benchmark cathode material for high-energy density lithium-ion batteries due to its high specific capacity (>200 mAh g⁻¹) and operating voltage (~3.8 V). However, its strong surface reactivity toward atmospheric species, particularly moisture and CO₂, poses significant challenges during storage and processing, leading to the formation of LiOH- and Li₂CO₃-rich surface layers. Although the effects of humid air have been widely investigated, a direct comparison between high relative humidity and pure CO₂ exposure remains limited. Here, we systematically examine the morphological, structural, chemical, and electrochemical evolution of commercial NMC-811 electrodes after 5 h exposure to 80% relative humidity or CO₂-saturated atmosphere. Moisture treatment induces substantial surface reconstruction, lattice shrinkage, and increased cation disorder, accompanied by extensive hydroxide and carbonate formation. In contrast, CO₂ exposure mainly modifies the outermost surface layer without significant bulk structural changes. Electrochemical testing reveals that CO₂-treated electrodes display higher initial polarization but quickly recover near-pristine performance, whereas humidity-treated electrodes exhibit persistent kinetic limitations, accelerated capacity fading, and earlier end-of-life. Overall, degradation severity follows the trend: pristine < CO₂ < RH 80%, highlighting the dominant role of moisture in irreversible structural deterioration. Full article

Environmental contaminants pose threats to exposed organisms and negatively impact the nervous, cardiovascular, immune, and reproductive systems. Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals that are ubiquitous in the environment. Given that mixtures of environmental contaminants have the potential to exacerbate toxicity, we reviewed the current literature on pesticides, microplastics, or metal exposure in combination with PFAS on aquatic vertebrates and invertebrates. The objectives were to evaluate the toxicological effects of mixtures of the selected contaminants with PFAS on aquatic organisms to better understand biological responses in animals. Based on our review, data suggest that PFAS can modify the toxicity of co-occurring pollutants. For example, synergistic effects on toxicity include chlorpyrifos + perfluorohexanoic acid (PFHxA), which increased reactive oxygen species (ROS) and upregulated neurotoxicity-related genes in zebrafish, and perfluorooctanoic acid (PFOA) + atrazine, which increased the presence of malformations and oxidative stress. However, antagonistic interactions were also observed, for example, reduced herbicide toxicity in PFOA + 2,4-dichlorophenoxyacetic acid (2,4-D) mixtures. PFAS combined with microplastics often intensified oxidative stress and developmental or reproductive effects, though polyethylene microplastics attenuated perfluorooctane sulfonic acid (PFOS)-induced immunotoxicity in fish like seabass. Interactions with metals also varied, with copper and cadmium enhancing oxidative stress while mercury mixtures with PFAS showed antagonism, underscoring the complexity of mixture effects in real environments. A computational approach demonstrated that PFOS can engage in intermolecular interactions with pesticides, microplastic monomers, and metals, suggesting chemical-level effects that could modify toxicity or bioavailability. Future studies should focus on elucidating the mechanisms underlying these complex interactions, investigating effects at different trophic levels and in a broader range of species, and should consider environmentally relevant mixtures. Full article

Microplastics (MPs) often co-occur with heavy metals (HMs), posing combined stress that inhibits plant growth. While plant growth-promoting bacteria (PGPB) are known to alleviate heavy metal toxicity, their role under MP–HM co-contamination and the differential responses of rhizosphere microbial communities remain unclear. This study evaluated the effects of cadmium (Cd) and lead (Pb), polylactic acid (PLA) MPs, and their combined contamination on spinach growth using pot experiments, and assessed the mitigation potential of two PGPB strains. PGPB inoculation significantly increased plant height and dry weight. High-throughput sequencing revealed that pollution treatments and PGPB altered rhizosphere bacterial and fungal community composition and diversity. Microbial shifts were closely associated with soil chemical properties and plant growth. Notably, bacteria and fungi exhibited distinct response patterns to combined stress and remediation. Functional prediction (PICRUSt2) indicated that microbial communities enhanced metabolic processes and nutrient (N and P) cycling to cope with stress. PGPB inoculation reduced heavy metal toxicity, improved soil nutrient status (P and K), increased microbial diversity, and regulated microbial functions, thereby supporting soil ecological stability. These findings provide insights into rhizosphere microbial mechanisms and support the application of PGPB for remediation of MP–HM co-contaminated soils. Full article

Flat glass waste from building demolition is an underused resource with potential to reduce the climate impact of construction materials. This study compares two recycling pathways for flat glass waste: the first is closed-loop recycling into new glass, and the second is the use of glass in concrete as a replacement for cement. The comparison is based on life cycle, circularity assessment and experimental evaluation of concrete performance. Recycling flat glass into new glass can reduce emissions by 945 kg CO₂eq per ton of recycled glass when the production mix contains 65 percent recycled content. However, only between 1 and 3% percent of demolition flat glass is suitable for this process because of contamination and quality limitations. As a result, the practical climate benefit of demolition glass in new glass production is limited to about 38 kg CO₂eq per ton of demolition glass. Concrete offers a much larger waste sink. Replacing 20% of cement with milled glass powder results in emission savings of 776 kg CO₂eq per ton of glass. A concrete mix containing 33% glass shows the same compressive strength as a reference mix. Full article

The chemical equilibria of metal ions between soil solution and solid phases govern the solubility of metals in soil. However, the identity of these controlling phases remains poorly understood in historically polluted environments. This study aimed to identify the dominant mineral phases regulating the activities of Zn²⁺, Cd²⁺, Pb²⁺, and Ni²⁺ in soils subjected to long-term contamination from sewage sludge, municipal solid waste, river water, and industrial effluents across India. The soil samples were collected from various locations historically polluted by sewage sludge, municipal solid waste, polluted river water and industrial effluents. The free ion activities of Zn²⁺ (pZn²⁺), Cd²⁺ (pCd²⁺), Pb²⁺ (pPb²⁺) and Ni²⁺ (pNi²⁺) in soil pore water were estimated using the geochemical speciation model WHAM-VII. The metal ion activities were higher in industrial effluents and solid waste-treated soils as compared to other contaminated soils. The solubility of Zn and Cd in soils contaminated with Zn-smelter effluents was controlled by franklinite (ZnFe₂O₄) in equilibrium with goethite (α-FeOOH) and otavite (CdCO₃), respectively. Identification of minerals further reveals that nickel ferrite (NiFe₂O₄) in equilibrium with lepidocrocite (γ-FeOOH) governs the activity of Ni²⁺ in cycle factory effluent-irrigated soils of Sonepat, Haryana. At the municipal solid waste-contaminated site, the Pb²⁺ activity was controlled by exchangeable Pb in soils, whereas Zn²⁺ activity was governed by willemite (Zn₂SiO₄) in equilibrium with quartz (SiO₂). These findings provide new insights into mineralogical controls on heavy metal solubility under diverse contamination scenarios. Formation of highly soluble minerals like otavite, willemite, and nickel ferrite suggested the potential ecological risk of Cd, Zn, and Ni, respectively, in polluted soils. Full article

Stabilization/solidification (S/S) is a crucial technology for the engineering reuse of oil-contaminated soil. A key challenge, however, is preventing the migration of residual oil under varying hydraulic conditions. This study investigates the efficacy of a lime and fly ash binder in treating oil-contaminated soil. We systematically compared the performance of untreated (UOCS) and treated (TOCS) soils under different aqueous environments (humidity injection, water injection, and permeation). We evaluated oil migration, water-holding capacity, and permeability characteristics. The results demonstrate that the lime–fly ash treatment effectively adsorbed and immobilized oil contaminants, restricting their mobility to a remarkably low range of 0.54% to 4.90%. Furthermore, the S/S treatment significantly improved the soil’s hydraulic properties: it enhanced the water-holding capacity, reduced the soil-water characteristic curve hysteresis, and counteracted the oil-induced hydrophobicity. Consequently, the effective permeation channels were restored, leading to a higher permeability coefficient in TOCS compared to UOCS. Crucially, the hydro-mechanical performance of the treated soil met the criteria of the Solidification/Stabilization Resource Guide, confirming its suitability for engineering applications. Full article

With the rapid progression of global industrialization and urbanization, heavy metal contamination has emerged as a major global threat, especially cadmium pollution. Consequently, optimizing remediation measures has become a pivotal means to solve cadmium contamination. Compared to traditional physical and chemical remediation methods, microbial remediation has great potential in addressing cadmium pollution. In this study, a novel bacterial strain, Chryseobacterium sp. HGX-24, exhibiting high cadmium resistance was successfully isolated and screened from cadmium-contaminated environments. A preliminary discussion of the response mechanisms of this strain under cadmium stress is provided. Additionally, preliminarily explored the synergistic remediation of microbial-plant in cadmium-contaminated soil. Under conditions of high cadmium concentration, cadmium ions were effectively adsorbed by strain HGX-24 through extracellular polymers and functional groups on the cell wall surface, including −COOH, −CONH−, −NH, −OH, and >C=O. Extracellular proteins and polysaccharides were secreted by strain HGX-24 to regulate the adverse effects of heavy-metal cadmium ions on bacterial growth. Furthermore, the expression of genes such as antioxidant defense and ROS scavenging (katG, fabG, ybjT), Fe-S cluster assembly (sufB, sufD), sulfur metabolism (cysAU), amino acid metabolism (hisA, cysD, aspC), phenylacetic acid catabolism (paaC), and ribosomal proteins (rplC, rpsC, rpsL, rplA, rplY, rpmC) was regulated, affecting the synthesis and metabolism of membrane transporters (ABC transporters and efflux RND transporters), antioxidant enzymes (SOD, COT, POD), Fe-S clusters, thioredoxin family proteins, and ribosomal proteins, thereby enhancing resistance to cadmium toxicity. Moreover, strain HGX-24 was found to regulate the activities of redox enzymes in Zea mays L., thereby alleviating oxidative stress and reducing the negative feedback effects of reactive oxygen species in Z. mays. Full article

The estuarine and coastal regions of India and Taiwan are under increasing threat from pollutants such as microplastics (MPs) and heavy metals including cadmium (Cd). These contaminants are known to have adversely affect biodiversity and water quality. In this study, the combined toxic effects of polyethylene microplastics (PE-MPs) and Cd were evaluated using Poecilia sphenops, a euryhaline fish species, selected for its adaptability to varying salinity conditions. P. sphenops were exposed to Cd (20, 40, and 60 μg/L), MPs (8, 16, 24 mg/L), and co-exposure combinations ranging from Cd 5 μg/L + MPs 4 mg/L to Cd 20 μg/L + MPs 16 mg/L Results showed significant (p< 0.05) negative effects on growth parameters including body weight gain, specific growth rate (SGR), and survival rate. Hematological analysis revealed significant (p< 0.05) decreases in hemoglobin (Hb), red blood cells (RBCs), and white blood cells (WBCs), indicating impaired oxygen transport and compromised immune function. Elevated blood glucose levels indicated physiological stress, while reduced total protein levels suggested a compromised nutritional status. Antioxidant enzyme activities, including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx), were significantly (p < 0.05) decreased in the toxicant-treated groups compared with the control. Digestive enzyme activities (proteases, amylases, and lipases) were also reduced, suggesting impaired digestion and nutrient assimilation. The study also included a comparative assessment of water quality between the exposed and control tanks. Water quality parameters such as turbidity, salinity, hardness, alkalinity, chloride, fluoride, and total suspended solids (TSSs) were elevated in the toxicant-treated media, accompanied by a notable decline in dissolved oxygen (DO) levels. These findings highlight the urgent need for integrated pollution control and water quality monitoring, particularly in coastal regions vulnerable to desalination discharges and plastic contamination. Sustainable management strategies must address these complex interactions between multiple pollutants to protect aquatic ecosystems. Full article

Miscanthus lutarioriparius exhibits strong potential for cadmium (Cd) accumulation, making it a promising candidate for the phytoremediation of Cd-contaminated soils. However, its full remediation potential remains underexploited, highlighting the need for targeted genetic improvement This study presents a comprehensive genome-wide identification and systematic characterization of 20 Ml4CL (4-coumarate: CoA ligase genes) in the M. lutarioriparius. Results indicate that the Ml4CL gene family has undergone substantial evolutionary divergence and expansion. Phylogenetic classification is highly consistent with gene structures ad conserved motifs suggesting potential functional diversification. Promoter analysis revealed a complex cis-regulatory landscape enriched in n ABA- and light-responsive elements, frequently co-occuring with hormone-responsive elements associated with jasmonic acid (JA), gibberellins (GAs), salicylic acid (SA), and strigolactones (SLs) signaling. This pattern suggests that the Ml4CL family may function as an integrative regulatory node linking multiple stress and hormonal signaling pathways. Importantly, under Cd stress, Ml4CL genes exhibited diverse expression dynamics, including gene-specific repression and dose-dependent biphasic responses. Notably, Ml4CL4 showed strong repression, while other members displayed “induction-then-repression” or “repression-then-induction” patterns, suggesting a staged or hierarichical transcriptional response. These findings further suggest that Cd-responsive signaling networks may involve non-linear or threshold-dependent mechanismsthat activate distinct transcriptional programs depending on stress levels. Collectively, this study highlights the regulatory role of the Ml4CL family in plant adaptation to complex environments and identifies candidate dose-resonsive regulatory elements and key allelic variations. These findings provide valuable targets for molecular breeding and synthetic biology aimed at improving crop stress resilience. Full article

Dissolved silicic acid (Si) in groundwater can reduce the As-removal performance of adsorbents used for treating contaminated water. However, its effects on Mg-based adsorbents remain largely unexplored. In this study, As-removal tests were conducted under various test conditions to evaluate the suitability of Mg-based adsorbents (MgO, Mg(OH)₂, and MgCO₃) for the purification of As-contaminated water in the presence of Si. As-removal performance varied significantly depending on the Mg-based adsorbent type and dosage (W_Ad0/V), As valence, and the initial As and Si (C_Si0) concentrations. In some cases, As removal improved at relatively low C_Si0; however, overall performance decreased with increasing C_Si0 for all Mg-based adsorbents. Moreover, compared with Mg(OH)_2, the performance of MgO and MgCO₃ was more strongly affected by Si. This inhibition is attributed to competition between Si and As for adsorption sites on the adsorbent surface. Furthermore, for MgO and MgCO₃, the amount of As removed by coprecipitation with secondarily generated Mg(OH)₂ aggregates was inferred to decrease with increasing C_Si0, because higher C_Si0 lowered the solution pH. Overall, MgO and Mg(OH)₂ can function effectively as adsorbents for As treatment when W_Ad0/V is appropriately selected, considering the range of Si concentrations typically found in groundwater. Full article

The evaluation of potentially toxic element concentrations (PTEs) in soils and plants is essential for understanding environmental quality and potential human exposure in areas affected by intense anthropogenic activity. This study addresses a research gap in the Valencian Region, focusing on soil–plant interactions of PTEs in urban and industrial environments. We assess the status of the soil–plant system in a region of the Valencian Community (eastern Spain) subjected to strong urban, industrial and agricultural pressure. A total of 55 soil samples and 47 plant samples were collected from agricultural, urban and industrial sites and analysed for soil properties, major elements (Al, Mg, Fe) and PTEs (As, Cd, Co, Cr, Cu, Li, Mn, Ni, Sr, V and Zn). Land use significantly influenced soil physicochemical characteristics, with clear differentiation among environments. Soil texture and organic matter were the main factors controlling element retention, while Al, Fe and Mg dominated the geochemical composition, consistent with Mediterranean calcareous soils. Correlation analyses revealed strong co-occurrence patterns among lithogenic elements (e.g., Fe-Al, r = 0.917 p < 0.01), soil texture and chemical properties, indicating a shared origin and preferential retention in the fine fraction and soil organic matter. Contamination indices identified potential environmental risk mainly associated with Cu, Pb, Sr and Zn, particularly in densely populated areas. Mean concentrations of Cd, Cr, Cu, Pb and Zn were, respectively, 0.63 mg kg⁻¹, 42.25 mg kg⁻¹, 31.49 mg kg⁻¹, 56.91 mg kg⁻¹ and 76.08 mg kg⁻¹. These elements exceeded Spanish regulatory reference values in several soils. Bioaccumulation indices indicated notable plant uptake of As, Sr and Zn, highlighting their potential for trophic transfer. Full article

This study investigates the degradation characteristics, pathways, and mechanisms of ochratoxin A (OTA) by Weizmannia coagulans CGMCC 9951 (W. coagulans CGMCC 9951), as well as its detoxification effect on Cornus officinalis pulp through fermentation. The strain efficiently degraded 300 ng/mL of OTA within 72 h (98% degradation) under optimal conditions of 37 °C, pH 5.0, and 180 rpm. Active degradation substances were primarily localized in the cell-free supernatant (CF). The degradation activity was significantly inhibited by heat treatment, proteinase K, EDTA, Cu²⁺, and organic reagents, suggesting an enzymatic mechanism. UHPLC-MS and MS/MS analysis indicated that OTA appears to be degraded to a product consistent with ochratoxin α (OTα). Based on homology to known OTA-degrading carboxypeptidases, the gene encoding WGU28473.1 was selected, expressed in E. coli, and confirmed to possess OTA-degrading activity. Molecular docking suggested potential interactions between the enzyme and OTA. Under optimal conditions, co-fermentation with Cornus officinalis pulp contaminated with 300 ng/mL OTA for 96 h resulted in a 74% degradation of OTA. The fermentation process increased the pulp’s sugar content and ABTS⁺ free radical scavenging capacity, reduced acidity, and improved the safety of the pulp. These findings demonstrate that W. coagulans CGMCC 9951 efficiently degrades OTA and improves pulp quality, highlighting its potential as a starter culture for detoxifying OTA-contaminated food. Full article