Search Results (1,748)

Heavy metals in lake sediments represent typical persistent contaminants characterized by recalcitrance, bioaccumulation potential, and delayed toxic effects, thereby exerting sustained adverse impacts on lacustrine ecosystem stability and human health. Liuye Lake is a representative small-to-medium urban lake impacted by ambient domestic sewage discharge and agricultural non-point source pollution, with documented nitrogen and phosphorus enrichment. However, the contamination profile of heavy metals in its surface sediments has not been systematically investigated to date. In this work, surface sediment samples were collected from Liuye Lake, and nine heavy metal elements (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn) were determined. An integrated approach incorporating Monte Carlo simulation, the geo-accumulation index (I_geo), and the enrichment factor (EF) method was employed to assess the ecological risk and human health risk imposed by these metals. The results revealed the following: (1) Average concentrations of eight heavy metals exceeded the background values of the Dongting Lake water system, with the exception of As, and Hg displayed potential localized anomalies. (2) Surface sediments were collectively categorized as slightly contaminated, with Hg identified as the primary pollutant, followed by minor contamination of Mn, Cr, and Ni; Monte Carlo simulation further suggested a probable risk that Mn contamination could progress to moderate levels. (3) All heavy metals posed low potential ecological risk, with an overall potential ecological risk index (RI) of 62.71, where Cd, Hg, and As were the dominant contributors. (4) Both non-carcinogenic and carcinogenic risks were generally within acceptable limits, whereas children exhibited higher non-carcinogenic susceptibility relative to adults; As and Mn were the leading contributors to non-carcinogenic risk, while Cr and As dominated carcinogenic risk. This study offers a scientific foundation for the prevention and control of heavy metal pollution and the ecological management of urban lakes. Full article

Contamination of agricultural soil by potentially toxic elements (PTEs) can be caused by volcanic emissions and the use of agrochemicals; this threatens human food security, as PTEs can be transferred from the soil to plant tissues. Sorghum is the fifth most important cereal crop worldwide, and Mexico is one of the countries with the highest sorghum production. However, these crops are vulnerable to pests; thus, agrochemicals are applied to eliminate them. In this study, the identification and translocation of PTEs into sorghum plants grown in urban and volcanic areas of central Mexico were evaluated. Sorghum plants and soil samples were collected at four sites (S1, S2, S3, and S4) in these areas. The concentrations of PTEs in the soil samples and in the different tissues of the sorghum plants were determined by inductively coupled plasma optical emission spectroscopy. It was found that these sites are contaminated with PTEs, which were attributed to volcanic emissions and anthropogenic activities. In addition, the translocation factor values for zinc, nickel, and manganese showed that these PTEs were retained in the roots of the sorghum plants; however, the average concentrations of these PTEs in the grains of the plants were higher than the translocation factor values. This result indicates that the aerial parts of the sorghum plants could have been contaminated with PTEs from the air, which could then enter humans throughout the food chain. Full article

Co-pyrolysis of sludge and plastics has gradually emerged as a crucial technical approach for waste reduction and resource recovery. This study develops high-precision, interpretable prediction models and quantifies the contributions of core risk factors to environmental risks. Based on the experimental datasets from 2015 to 2025, which include operational parameters and eight potential toxic elements (PTEs) with four chemical speciation fractions: acid-soluble/exchangeable (F1), reducible (F2), oxidizable (F3), and residual (F4), we constructed six machine learning models. Based on the experimental datasets from 2015 to 2025, which include operational parameters and eight potential toxic elements (PTEs) chemical speciation (F1–F4), we constructed six machine learning models. Feature importance analysis and Shapley Additive Explanation (SHAP) analysis were employed to identify core risk factors and interpret the model’s decision logic. Results indicate that XGBoost, Random Forest and CatBoost outperform other models, achieving test accuracies of 0.94, 0.92, and 0.90, with weighted F1-Scores of 0.94, 0.92, and 0.90, respectively. Feature importance highlights the most important features for the six different models, with Cd-F4, As-F1, and Cu-F4 contributing most significantly to the model predictions. SHAP analysis quantified the contributions of each feature to the model predictions, verified Cd-F4 as the primary risk discriminant, and further revealed that F1 and F4 of PTEs are key factors in distinguishing risk levels. This study proposes an interpretable machine learning framework, providing a theoretical basis for the optimization of the sludge and plastic co-pyrolysis process and the assessment of potential risks. Full article

Micronutrient deficiencies in human diets, often exacerbated by soil degradation, pose a significant global health challenge. Glacial flour, fine sediments produced by glacial erosion, may offer a sustainable, low-cost solution to improve soil fertility and enhance micronutrient availability in crops. This study evaluates the potential of glacial flour soil amendments from glaciers with two contrasting lithologies—basaltic Sólheimajökull (Iceland) and metasedimentary Chhota Shigri (Himalaya)—to enrich soybeans (Glycine max var. Black Jet) with essential nutrients while assessing the risk associated with potentially toxic elements. In a controlled glasshouse experiment, soybeans were grown in artificial soils amended with five doses of glacial flour (0.5–20 T ha⁻¹) and analysed for 18 elements. Results demonstrated enhanced uptake of key nutrients such as Zn, Fe, Mo, and Se, particularly in Icelandic glacial flour treatments, supporting the potential for crop biofortification. However, Himalayan flour led to arsenic (As) accumulation at higher doses, exceeding food safety limits. Multivariate clustering revealed two distinct element uptake behaviours: oxyanion-mediated and mimicking elements (Mo, Se, Sr, As) and those driven by plant demand (macronutrients, Fe, Mn, Zn). These findings highlight glacial flour’s potential for nutrient enrichment but also of potentially toxic elements, underscoring the need for source-specific screening to ensure safe agricultural application in deglaciating regions. Full article

In this study, the variation in chromium (Cr) and cadmium (Cd) concentrations in peppers, tomatoes, corn, eggplants, and cucumbers grown adjacent to the industrial area in Düzce, one of Europe’s most polluted cities and known for its high levels of potential toxic element (PTE) pollution, was determined based on species and organ. In addition, the concentrations of these elements in the soil were determined, and the translocation factor (TF) and bioconcentration factor (BCF) in the plant organs were calculated. The study found that Cr pollution, in particular, was well above threshold values in the region and accumulated to high concentrations in all plant organs, including fruits. The study found that soil Cr concentrations were well above the limit values set by international organizations. Cd concentrations in fruits ranged from 0.22 mg/kg to 0.33 mg/kg. Based on these results, Cd concentrations in all species exceed the limit values set by international standards by more than twice. The Cr concentration determined in fruits in the study ranged from 178.47 mg/kg to 579.80 mg/kg. According to these values, the Cr concentration determined in fruits is hundreds of times higher than the limit value in all species. TF values were high for Cd in tomato fruits and Cr in pepper and cucumber fruits. In contrast, TF values for both Cd and Cr were very low in corn fruits. Based on these results, cultivating crops such as tomatoes, cucumbers, and peppers should be avoided in the region, and corn should be emphasized. Thus, the rate of Cr and Cd entering the human body through the food chain can be reduced. Full article

Rare earth elements (REE), such as gadolinium (Gd) and erbium (Er), are increasingly recognised as emerging environmental contaminants due to their widespread use in industrial processes, electronics, and medical imaging applications. Despite their extensive presence in aquatic ecosystems, little is known about their developmental toxicity. In this study, Xenopus laevis embryos were exposed to environmentally relevant concentrations of Gd and Er during critical early developmental stages. The assessed endpoints included survival, malformations, growth (body length), and heart rate. Both Gd and Er caused significant sublethal effects, including increased axial malformations, reduced growth, and altered cardiac activity. To explore potential mechanisms of toxicity, the expression patterns of key developmental genes (fgf8, bmp4, sox9, egr2, rax1, pax6) and pro-inflammatory cytokines (tnfα, il1β, p65) were analysed using Real-Time PCR. The results showed dysregulation of gene expression, indicating disruption to pathways involved in morphogenesis and neurodevelopment. Elevated reactive oxygen species levels suggested that oxidative stress was a contributing factor. Raman spectroscopy confirmed biochemical changes affecting proteins, lipids, and nucleic acids, providing evidence of cellular stress and metabolic imbalance. Overall, our findings demonstrate that even low-level exposure to Gd and Er can impair amphibian embryonic development and disturb molecular homeostasis. These results emphasise the ecological risks of REE pollution and highlight the importance of ongoing environmental monitoring and long-term toxicological research. Full article

Background: Cryopreservation induces oxidative stress, membrane disruption, and mitochondrial injury in spermatozoa, leading to impaired motility and fertility. Selenium, as an essential trace element, protects cells from oxidative damage through selenoproteins such as glutathione peroxidase 4 (GPX4), a critical enzyme that detoxifies lipid hydroperoxides and inhibits ferroptosis. This study investigated whether supplementation with L-selenomethionine (L-SeMet), an organic selenium source with superior bioavailability and lower toxicity than inorganic forms, could alleviate cryo-induced sperm injury by suppressing ferroptosis. Methods & Results: Dairy goat sperm were cryopreserved with 0, 2, 4, 6, 8, 10 μM L-SeMet. Supplementation with 6 μM L-SeMet significantly improved motility, membrane and acrosome integrity, and mitochondrial membrane potential. Biochemical assays showed reduced iron, ROS, and MDA levels, alongside increased ATP, SOD, and GSH contents. Proteomic analysis identified 148 differentially expressed proteins, including up-regulation of GPX4, FTH1, VDAC2, and VDAC3—core ferroptosis regulators. Metabolomic profiling further revealed enrichment in unsaturated fatty acid biosynthesis, amino acid metabolism, and the TCA cycle, pathways closely linked to ferroptosis regulation. Transmission electron microscopy confirmed that L-SeMet preserved mitochondrial ultrastructure. Mechanistically, L-SeMet mirrored the ferroptosis inhibitor N-acetyl-L-cysteine and reversed RSL3-induced oxidative damage. Western blotting verified activation of the NRF2–SLC7A11–GPX4 antioxidant axis and inhibition of KEAP1 expression. Conclusions: Collectively, these findings demonstrate that L-SeMet protects spermatozoa from cryo-induced injury by stabilizing redox homeostasis, maintaining mitochondrial function, and inhibiting ferroptosis. The results highlight ferroptosis as a critical mechanism of sperm cryodamage and identify L-SeMet as a promising metabolic intervention to enhance post-thaw sperm quality and fertility. Full article

It is estimated that at least 16.1% of croplands in China are polluted with heavy metals, and cadmium (Cd) is a typical toxic element inhibiting plant growth. Sorghum bicolor × S. sudanense, a C4 plant with high biomass and stress tolerance, has potential for phytoremediation, but its Cd tolerance mechanism remains unclear. In this study, physiological and transcriptomic responses of Cd-tolerant (S6) and sensitive (2190A/201900131) cultivars were analyzed under 25 mg/L Cd stress. The results showed that S6 exhibited milder phenotypic inhibition (leaf yellowing, growth retardation) than the sensitive cultivar. Cd was mainly accumulated in roots (S6: 4988.37 mg/kg; sensitive: 7030.06 mg/kg at 7 d), with S6 having a lower translocation factor. Physiologically, S6 maintained higher chlorophyll content, stable photosynthetic efficiency (Fv/Fm, PI), and lower malondialdehyde (MDA) accumulation, while antioxidant enzyme (SOD, CAT, APX) genes were significantly upregulated. Transcriptomic analysis identified 47,797 differentially expressed genes (DEGs), enriched in glutathione metabolism, ABC transporter-mediated transport, metal chelation, and antioxidant defense pathways. Genes related to cell wall biosynthesis, metal transporters (ZIP, HMA), and transcription factors (MYB, WRKY) were synergistically upregulated in S6, enhancing Cd sequestration and detoxification. These findings clarify the physiological and molecular mechanisms of Cd tolerance in Sorghum bicolor × S. sudanense, providing a basis for its application in Cd-contaminated soil phytoremediation. Full article

Cholestasis in children is characterized by impaired bile flow that disrupts hepatic metabolism, nutrient homeostasis, and effects trace element balance. This narrative review summarizes current evidence on the metabolism, biological functions, and clinical implications of key trace elements—zinc, selenium, copper, and manganese—in pediatric cholestatic liver disease. The liver regulates trace element absorption, intracellular trafficking, storage, and biliary excretion; cholestasis alters these processes, leading to deficiencies or toxic accumulation. Zinc and selenium deficiencies are common and contribute to impaired growth, immune dysfunction, oxidative stress, and delayed hepatic regeneration. Conversely, reduced biliary excretion promotes copper and manganese accumulation, potentially exacerbating liver injury and causing manganese-related neurotoxicity. Recent advances in understanding metal-specific hepatic transporters and trafficking pathways have provided mechanistic insight into these alterations. Management strategies emphasize individualized supplementation, monitoring during enteral and parenteral nutrition, and prevention of deficiency and toxicity. Precision-based nutritional approaches may improve outcomes in pediatric cholestatic liver disease. Full article

Human activities inevitably affect natural ecosystems, the impact of which most often refers to negative factors resulting in the accumulation of toxic elements in environmental components. This study quantified the presence of 12 toxic elements (Cd, Co, Cr, Cu, Hg, Fe, Mn, Ni, Pb, Zn, As, and Se) in water, soil, and six melliferous plant species across the Republic of Croatia. Sampling sites were classified into four groups according to the dominant anthropogenic impact: agricultural areas, urban and traffic-affected zones, industrial vicinities, and forested hill regions. The results demonstrate the transfer of toxic elements from abiotic matrices into plants, indicating their potential as bioaccumulators. Soil contamination with toxic metals was identified as a relevant ecological risk factor, while contamination of melliferous plants highlights potential implications for human health through the production of honeybee-derived products. Element concentrations in water and soil were determined using three atomic absorption spectrometry techniques (FAAS, GFAAS, and CVAAS), whereas concentrations in floral samples of melliferous plants were measured using inductively coupled plasma mass spectrometry (ICP MS). The obtained results were interpreted in relation to natural background levels and the current national legislation. Anthropogenic impacts were further evaluated using environmental quality indices and bioaccumulation factors, revealing site-specific contamination patterns of both natural and anthropogenic origin. Full article

This study developed and evaluated multifunctional Cu-doped Zeolitic Imidazolate Framework-8 nanoparticles coated with hyaluronic acid (Cu-ZIF-8@HA) for antimicrobial application on stainless-steel food-contact surfaces. Structural characterization through SEM, TEM, and elemental mapping confirmed the successful synthesis, uniform Cu incorporation, and HA coating without compromising the crystalline ZIF-8 framework. Cu doping reduced particle size (~130 nm) and enhanced redox activity, while HA encapsulation improved colloidal stability and biocompatibility by shifting zeta potential from positive (+22.1 mV) to negative (−18.7 mV). Cytotoxicity assays demonstrated that HA significantly mitigated metal-induced toxicity, maintaining >70% cell viability at ≤1000 µg/mL. Antibacterial assessments revealed potent activity against Salmonella Typhimurium ATCC 14028 and Escherichia coli O157:H7, with Cu-ZIF-8@HA exhibiting the largest inhibition zones (18.15–20.33 mm), lowest MIC/MBC values (500/2000 µg/mL and 1000/2500 µg/mL), and over 6-log reductions in bacterial adhesion on stainless steel. Enhanced wettability (contact angle 11.77°) and surface energy (64.42 mN/m) further facilitated antimicrobial contact. These results confirm that Cu-ZIF-8@HA integrates the oxidative potency of Cu, the structural stability of ZIF-8, and the biocompatibility of HA, offering a promising and safe nanomaterial platform for controlling bacterial contamination and biofilm formation in food-processing environments. Full article

Heavy metals in urban dust, derived from anthropogenic activities and natural sources, are considered potentially toxic elements for human health. The city of Puebla, located in Central Mexico, is one of the ten largest metropolitan cities in Mexico. Near this city is the Popocatépetl volcano, which contributes heavy metals through the emission of ash. The objectives of this study were to evaluate heavy metal contamination in urban dust and volcanic ash from the city of Puebla, and to determine the associated human health risks. Heavy metals were analyzed using an XRF spectrometer. The level of contamination was established according to the contamination factor, the geoaccumulation index and the contaminant load index. Furthermore, non-carcinogenic risk indices (HIs) were calculated to evaluate the health risk. The results revealed the presence of 18 elements (Ca, Cr, Cu, Fe, K, Mn, Nb, Ni, Pb, Rb, Sb, Sn, Sr, Ti, Y, V, Zn and Zr), with the highest concentrations found for most in urban dust samples, while Rb, Ca and K showed higher concentrations in ash samples. High levels of Sb and Sn contamination were found in 90 to 100% of the dust and ash samples, while Cr, Cu, Ni, Pb and Zn showed considerable levels of contamination in 60 to 90% of the samples. According to the US EPA thresholds, the health risk assessment indicated safe levels (HI < 0.25) for Cu, Fe, Mn, Ni, Pb, Sn, V and Zn in the urban dust and volcanic ash samples, while some of the samples exceeded the safety threshold (HI > 1) for Cr and Sb with respect to the child population in the city of Puebla. These results must be taken into consideration by environmental and government authorities, and the degree of pollution should be reduced accordingly. Full article

The elemental composition of the vitreous humor may reflect physiological and pathological processes occurring in the eye. The objective of this study was to provide a complex multielemental analysis of human vitreous humor. Vitreous humor samples (n = 57) were collected post-mortem during autopsies. Inductively coupled plasma mass spectrometry (ICP-MS) was employed to quantify micro-, trace-, ultra-trace, and toxic elements. The study showed the occurrence of elements at the ppm (Na, K, P, Ca, Mg), ppb (Al, Rb, Zn, Fe, Sr, Cu), and ppt (Ce, La, Nd, Tb) levels. Hierarchical clustering using Ward’s method and k-means analysis revealed four distinct clusters, including two major clusters representing the baseline macro- and microelement profile characteristic for the studied population. Correlations between elements revealed statistically significant (p < 0.05) positive and negative correlations between elements with (I) chemical similarity Ce-La, Cs-Rb, Rb-K, Ca-P, Zn-Cu, and Cs-K; (II) a possible common environmental origin, Cd-P, and Rb-P; (III) involvement in similar biological processes as K-P; and (iv) a common geochemical origin and similar biological functions, i.e., Se-Zn. The study identified several quantitative trends in the demographic and medical characteristics of the participants. Alcohol users had significantly higher Zn concentrations than non-alcohol users; women had significantly higher Ca concentrations than men; higher BMI correlated positively with Cs and negatively with Be and Cr levels; and Cu, Sb, Cd, Se, and Ca concentrations increased with age. The presence of several toxic and potentially toxic elements was identified in the vitreous body: Al (>10 ppb); Cd, Cr, Pb, Ni, Mn; and Ba (<10 ppb); As, Hg, Sb, Tl, Bi, Be (<1 ppb). The study showed that, within a given geographic region, the accumulation profiles of toxic metals are quite homogeneous, indicating common sources of exposure. Full article

Drug repurposing in oncology is often framed as a drug–target matching exercise, yet many candidates with plausible biological rationales fail in the clinic. In solid tumors, therapeutic outcomes are constrained not only by pharmacological target relevance but also by limited tumor accessibility, heterogeneous intratumoral exposure, loss of context-dependent activity, and dose-limiting systemic toxicity. This perspective argues that repurposing strategies should treat exposure engineering as a design principle alongside molecular selectivity. Peptides that bind cell- or matrix-associated molecules at the tumor site have the potential to implement spatial, temporal, and subcellular control over where and when a drug engages its pharmacological target, thereby enabling confinement of polypharmacology to tumor contexts. Mechanistic modes of peptide-enabled exposure selectivity (homing, anchoring/retention, conditional activation, penetration enhancement, and subcellular biasing), key failure modes, and translational constraints are discussed, together with an exposure-centric screening workflow to prioritize repurposed agents most amenable to peptide-guided rescue. Emphasizing the combination of exposure control and the addressing-element layer clarifies when and how pharmacologically promiscuous drugs may be repurposed safely and effectively. Full article

Microplastic (MP) pollution represents a significant environmental threat, impacting aquatic ecosystems and human health. This review examines critical elements of MP risk assessment, including exposure pathways, properties (polymer type, size, and shape), bioaccumulation, and ecological and health effects. It underscores the challenges of quantifying MP exposure and identifying pollutants, as well as gaps in understanding pollutant adsorption/desorption and biofilm impacts. MPs serve as carriers for organic pollutants, heavy metals, and chemical additives, potentially magnifying toxic effects. Emerging contaminants, such as pharmaceuticals, exacerbate these risks. Laboratory research is crucial to trace MPs through food chains from primary producers to humans and assess bioaccumulation and health impacts. Current assessments, however, are insufficient to provide comprehensive ecological risk evaluations. The review highlights the need for improved methodologies to assess MPs’ fate, trophic transfer, and long-term ecological effects. MPs often release harmful additives like plasticizers and flame retardants, necessitating studies to differentiate the impacts of polymers and additives. It emphasizes integrating MP toxicity data into risk models while fostering collaboration among scientists, policymakers, and communities. The paper advocates for a comprehensive framework combining advanced analytical methods and environmental monitoring to refine risk assessment models. These efforts aim to strengthen public awareness, support informed environmental policies, and promote sustainable practices to mitigate MP pollution impacts. Addressing these research gaps will significantly enhance the scientific understanding of MP risks and guide effective management strategies for environmental and human health protection. Full article