Impact of heavy metals on the environment and human health: Novel therapeutic insights to counter the toxicity

A novel approach for calculating food safety models and health risk assessments of potentially toxic elements (PTEs) in cow milk

This study introduces the Milk Quality Index (MQI), a novel metric for assessing milk quality that utilizes machine learning to enhance predictive accuracy. Lead (Pb) levels (318 ± 185 mg/kg) exceeded safety limits, with chromium (Cr), aluminum (Al), and selenium (Se) also raising concerns in raw cow milk from southwestern Iran. The MQI classified 80 % of samples as 'Fair' (range: 3.95-7.03, mean: 5.46), with random forest (RF) modeling confirming Se, calcium (Ca), and magnesium (Mg) as key contributors. Health risk assessments revealed elevated noncarcinogenic (HI50th = 2.48) and carcinogenic (TCR50th = 2.39E-4) risks in children. At the same time, arsenic (As) and nickel (Ni) had the greatest impact on the HI and TCR, respectively. Approximately 96.78 % of children and 98.96 % of adults may be exposed to elevated carcinogenic risks, respectively. This approach highlights the importance of PTE monitoring in milk to enhance food safety and protect public health.

Heavy metals are liver fibrosis risk factors in people without traditional liver disease etiologies

Liver fibrosis is an important predictor of mortality. Liver disease case definitions changed in 2023. These definitions include an easily over-looked group with no traditional etiology (NTE) of liver disease and no steatosis. We analyzed heavy metals and cardiometabolic risk factors (CMRFs) as fibrosis risk factors in the NTE group and in people with another newly-defined condition, metabolic dysfunction-associated steatotic liver disease (MASLD). Two National Health and Nutrition Examination Survey (NHANES) datasets were analyzed. In NHANES III (1988-1994), fibrosis and steatosis were defined by Fibrosis-4 scores and ultrasound, respectively, in 12,208 adults. In NHANES 2017-2020, fibrosis and steatosis were defined by transient elastography and the controlled attenuation parameter (CAP) in 5525 adults. Fibrosis risk factors varied over time and by race/ethnicity. In the earlier dataset, NTE-fibrosis had a positive, non-significant, association with high blood levels of lead (Pb). MASLD-fibrosis was associated with Pb (OR = 2.5, 95 % CI, 1.4-4.4) and not with CMRFs in non-Hispanic Blacks but was associated with CMRFs in non-Hispanic Whites. Heavy metal exposures fell between the two time periods. In the later dataset, NTE-fibrosis was associated with Pb (OR = 4.2, 95 % CI, 2.6-6.8) and cadmium (OR = 1.8, 95 % CI, 1.1-3.0) in the total population, but not with most CMRFs. MASLD-fibrosis was strongly-significantly associated with CMRFs in every racial/ethnic group except non-Hispanic Blacks in whom CMRFs were only weakly associated with MASLD-fibrosis. Heavy metal pollution, which disproportionately impacts minoritized populations, decreased over time, but remained strongly associated with liver fibrosis in people lacking traditional etiological factors for liver disease.

A near-infrared "turn-on" fluorescent probe for selective detection of copper(II) ions in aqueous media and its application in cell imaging

Copper (II) is considered the third most essential trace element for life, following iron and zinc, and plays a vital role in various physiological and pathological processes. The fluorescent probe has become an important method for the detection of heavy metal ions. This investigation involved the development and synthesis of a near-infrared "turn-on" fluorescent probe, DCX-Cu, with a significant Stokes shift (156 nm), specifically to identify Cu2+ compared other ions. A detection limit (LOD) of 19.47 nM for Cu2+ was demonstrated by probe DCX-Cu. A strong linear correlation was observed between the fluorescence intensities measured at 746 nm and the concentrations of Cu2+. Furthermore, the current probe successfully visualized Cu2+ in water samples and HepG2 cells.

Impact of heavy metal toxicity on the human health and environment

Heavy metals are among the major categories of pollutants that are widespread and have enormous potential to affect the environment and public health. Today, the toxicity of heavy metals has become a challenge since it is highly toxic and can accumulate in the body system. Heavy metal contamination results from various natural and anthropogenic activities that release these elements into the environment. Consequently, heavy metals contribute to multiple forms of environmental pollution and pose serious health risks to humans. This review seeks to give an understanding of the characteristics and toxicity of several heavy metals. Some of the physicochemical properties of heavy metals that give them their toxicity as well as the many ways that they can be introduced into the environment are described in the review. Other factors including the type of heavy metals, dose of exposure, route of exposure, duration of exposure, interaction with other chemicals, and environmental factors are further examined to establish the effects on the toxicity of heavy metals. In addition, the reviews also point to the impacts of these pollutants on water, plants, and human beings as regards ecotoxicological consequences. Last but not least, prospects to justify the novelty of diverse assessment and monitoring techniques for handling these contaminants have been presented. Thus, there are several opportunities to design strategies for mitigating the removal of such contaminants by combining the understanding of the toxicity of heavy metals. Overall, this review gives adequate information to researchers and academicians on the toxicity of heavy metals that can be used to design ways of opposing these pollutants and thus protecting the environment towards the development of a sustainable future.

Biomarkers of heavy metals pollution in mangrove ecosystems: Comparative assessment in industrial impact and conservation zones

Heavy metal contamination from industrial activities in coastal regions can lead to pollution in mangrove ecosystems. Mangroves produce antioxidant compounds to mitigate the impact of free radicals. This study aimed to analyze the correlation between the concentration of heavy metals Pb and Cu and antioxidant activity in Avicennia alba and Excoecaria agallocha mangroves from areas affected by industrial activities and conservation areas, Banyuasin, South Sumatra, Indonesia. This study was conducted in September 2023 with sampling locations in the Payung Island area and the Barong River conservation area, Berbak Sembilang National Park. The samples taken included sediment and mangrove leaves. The concentration of heavy metals Pb and Cu was measured by atomic absorption spectrometry. Antioxidant activity test using the DPPH test, total phenol using the Folin-Ciocalteu method, and phytochemical profile screening using GCMS. Statistical analysis of the correlation between antioxidant activity and heavy metal concentration using the Pearson correlation. The results showed that the highest concentration of heavy metals in sediment and mangrove leaves was found in the area affected by industrial activity, with a range of Pb values of 0.67 ± 0.16-18.70 ± 0.48 mg/kg and Cu values of 3.39 ± 0.20-6.07 ± 0.37 mg / kg. The results of sediment pollution assessment for heavy metals Pb and Cu at Igeo < 0 indicates uncontaminated, 1 < Cf < 3 indicates low contamination, and PLI 0-2 indicates not polluted. While the results of heavy metal bioaccumulation in leaves were BCF < 1, indicates low bioaccumulation. E. agallocha leaves from the Pulau Payung area showed very strong antioxidant activity of 21.63 μg/ml, and the highest total phenol content reached 398.80 mg GAE/g. Analysis of compounds with the highest antioxidant activity identified the presence of esters, aldehydes, alcohols, fatty acids, glycosides, flavonoids, terpenoids, and steroids. Correlation analysis shows that higher heavy metal concentrations correspond to increased antioxidant activity and total phenol content (r ≠ 0). These findings are expected to contribute to scientific knowledge that enhances environmental sustainability, supporting effective management of coastal natural resources.

Assessing heavy metal pollution levels and associated ecological risks in peatland areas in the Mekong Delta region

Heavy metal (HM) pollution in soils and sediment is a significant concern, yet its levels and ecological risks in peatland areas remain unexplored. This study evaluates these aspects in three peatland regions of the Long An province in Vietnam. Comparisons of HM concentrations in peatland sediments from Tan Thanh, Thanh Hoa, and Duc Hue provinces in the study locations revealed highest values in the Tan Thanh region. Specifically, Cu and Ni were found in sediments at levels two to three times higher than the threshold effects level (TEL) and the effects range median (ERL) guidelines. The main sources of HM pollution in the study area are predicted to include the production and use of fertilizers and pesticides, metal surface processing, mechanical engineering and electronics manufacturing, and chemical plants. Further, positive correlations between HM concentrations and factors such as pH, total organic carbon (TOC), and clay-silt ratio in the sediments were identified through Spearman correlation analysis. The results obtained from the correlation analysis were further corroborated by Bayesian network analysis, which was also applied in this study. In addition, the contamination factor (CF) index indicated that Ni has a pollution level of "moderate degree" in Thanh Hoa (CF = 1.3) and "considerable degree" in Tan Thanh (CF = 3.2), whereas, Cu has a pollution level of "moderate degree" in both Thanh Hoa (CF = 1.3) and Tan Thanh (CF = 2.4). The modified degree of contamination (mCd) ranked the areas as Tan Thanh > Thanh Hoa > Duc Hue, with mCd indexes of 1.3, 0.7, and 0.4, respectively. The potential ecological risk index (RI) indicated a "low risk" level, with an average RI of 35.6 across all sites. These findings address knowledge gaps in HM pollution in peatlands but also contribute to the development of strategies for the protection of peatlands.

Harnessing the interplay of protein posttranslational modifications: Enhancing plant resilience to heavy metal toxicity

Heavy metals (HMs) toxicity finds substantial plant health risk, affecting germination, growth, productivity, and survival. HMs exposure can interrupt cellular function, increase oxidative stress and affect physiological processes. Plants have developed array of adaptive responses, with proteins playing key role in detecting, signalling, and mitigating metal-induced stress. Under stress, posttranslational modifications, including phosphorylation, ubiquitination, glycosylation and acetylation, are essential regulators of protein stability, localization, and function. This review examines the comprehensive profiling of PTMs in HMs stress responses, including how PTMs regulate the signalling pathways, degradation pathways, and TFs modulation. Specifically, discuss the role of phosphorylation, ubiquitination, and sumoylation, neddylation, lipidation, and S-nitrosylation in specifically under HMs stress with PTMs regulation of antioxidant enzymes, stress proteins, metal transporters and chelators of detoxification. This review illustrates the crosstalk of PTMs to show how synergistic interactions regulate protein stability, activity, and localization upon HMs stress. In cross talk, ubiquitination often starts from phosphorylation to subsequent degradation of proteins in a timely and reversible way to trigger stress responses. However, sumoylation stabilizes key transcription factors that are rapidly dephosphorylated and integral in metal detoxification, form a synergistic combination with phosphorylation to maintain their activity. It explains the future research directions, focusing on PTM engineering to generate stress tolerant plant varieties. By studying the response of plants to HMs stress through PTMs, emphasizes the relevance of PTMs towards plant resilience and advocates for systems biology integrative approach to advancing plant stress biology.

Health risk assessment upon exposure to groundwater arsenic among individuals of different sex and age groups of Vaishali district, Bihar (India)

Availability of safe drinking water is one of the requirements for maintaining good health. Unfortunately, inhabitants of many nations suffer from adverse health effects due to the intake of arsenic-contaminated groundwater. The Vaishali district of Bihar (India) is the part of Ganga River Basin, a hotspot of arsenic contamination and hence, risk assessment among its individuals is highly pertinent. This study aimed to evaluate the extent of arsenic contamination in the ground waters of Bidupur block under Vaishali district, followed by an assessment of health risk, both non-cancer and cancer, within the arsenic-exposed adult females, adult males and children. Estimation of groundwater arsenic was done in 68 duplicate samples through an MQuant test kit (Merck, Germany). For this, Microsoft Office Excel and ArcGIS software were used as a tool. The results showed that only one-fourth of the groundwater samples exceeded the WHO permissible limit of arsenic with a high contamination factor. The total hazard index (HI), representing the non-cancer risk, was found above the threshold value (>1) among all individuals, which was high among the adults, more in adult females (3.21) than adult males (2.97), and low among the children (2.02). The cancer risk, expressed in terms of cancer index (CI), was also beyond the acceptable limit (10-4 to 10-6) among all sex and age groups, ranging from 0.91 × 10-3 to 1.45 × 10-3. Conclusively, arsenic was found to pose both high non-cancer and cancer risks in the population even at its low level due to long-term exposure.

Multi-omics insights into the mechanisms of muscle damage induced by molybdenum exposure in goats

Molybdenum (Mo) is an essential trace element, yet excessive intake can result in toxicity, adversely affecting animal health and food safety. Due to increasing environmental Mo contamination from industrial and agricultural activities, understanding its toxic effects on livestock is of global concern. This study aimed to investigate the molecular mechanisms of Mo-induced muscle damage in goats using an integrative multi-omics approach. Twenty black goats were divided into a control group (CJM) and a Mo-exposed group (JM; 50 mg/kg Na2MoO4·2 H2O), and fed for 60 days. Compared with the CJM group, the JM group showed significantly reduced muscle fiber diameter, average cross-sectional area, and levels of sulfur, iron, copper, and zinc, along with significantly increased Mo accumulation (p < 0.05). Compared with the CJM group, the JM group showed significantly reduced cysteine, methionine, proline, glutamate, and arginine (p < 0.05). Metabolomics identified 274 significantly altered metabolites, primarily enriched in energy and amino acid metabolic pathways. Proteomics revealed 221 differentially expressed proteins related to stress response, protein synthesis, and energy metabolism. These proteins interfere with muscle development by affecting cell stress responses, protein synthesis, and energy metabolism pathways. Moreover, the protein digestion and absorption and sulfur metabolism pathways were significantly associated with both metabolomics and proteomics. We found that Mo exposure primarily affects muscle energy and amino acid metabolism, thereby impairing muscle development in goats. This is the first study to use multi-omics integration to elucidate the mechanism of Mo-induced muscle toxicity in goats, providing new insights into heavy metal toxicity and food safety risks in livestock.

Analytical study, environmental risk assessment, and toxicity-based bioassays of effluents from phosphate fertilizer industry: a case study in Gafsa mining basin (SW Tunisia)

The phosphate fertilizer industry (PFI) in M'dhilla-Gafsa, Tunisia, discharges untreated effluents, creating environmental concerns due to unknown composition and toxic effects, leading to potential ecological and human health risks. This study characterized wastewater from three sampling points (SP1, SP2, SP3), and revealed their high acidity pH (2-3) and salinity (32.5-96.23 g/L). BOD5/COD ratios indicated the high recalcitrance (0.01-0.1) of the effluents, reflecting their low biodegradability and persistence in the environment. Excessive levels of phosphorus (206-2094 mg/L), fluoride (154-1071 mg/L), and sulfates (835.5-9266 mg/L) were detected by ionic chromatography. ICP-MS analysis highlighted for the first time the potentially toxic elements (PTEs) content in Tunisian PFI effluent, such us Cd (0.31-0.44 mg/L), Al (7.1-27.8 mg/L), Mn (1.9-3.5 mg/L), B (15.9-25.2 mg/L), Fe (15.7-28.7 mg/L), Ni (0.37-0.48 mg/L), and Cr (1.1-2.12 mg/L). These levels exceeded the permissible national and international limits for industrial discharges, as well as those of the World Health Organization (WHO) for drinking water, indicating serious potential environmental risks. Moreover, phytotoxicity tests on Medicago sativa, Pisum sativum, and Zea mays showed decreased amylolytic and proteolytic activities during germination. Blood toxicity assays indicated significant hemolytic effects. Indeed, 50% of SP1, SP2, and SP3 wastewaters caused hemolysis percentages equal to 52.04%, 57%, and 66.77%, respectively, implying therefore an acute toxicity of the effluents. Additionally, HEK-293 cells mortality was higher after exposure to effluents, with IC50 of 12.06%, 24.23%, and 17.68% for SP1, SP2, and SP3, respectively. These findings emphasized the potential risks posed by PFI effluents to the surrounding ecosystem and the agricultural sector, leading to the contamination of the food chain. This alarming threat imposes stricter wastewater treatment measures and regulatory enforcement in the PFI sector.

Porphyrin-Based Sorbents for the Enrichment and Removal of Metal Ions

Porphyrins and their derivatives are excellent materials with specific physical and photochemical properties in medical, chemical, and technological applications. In chemistry, their properties are applied to create new functional materials with specific characteristics, such as porphyrin-based sorbents combined with porous organic polymers, silica, carbon nanostructures, or metal-organic frameworks. This review covers the applications of porphyrins and metalloporphyrins in preparing and using sorbents for metal ion enrichment and their separation. Uncommon applications that utilize specific properties of porphyrins, such as light-enhanced processes and redox properties for selective sorption and photocatalytic conversion of metal ions, are also discussed. These applications suggest new fields of use, such as the removal or recycling of metals from electronic waste or the selective elimination of heavy metals from the environment.

Inversely Vulcanized Porous Copolymer Monolith for Efficient Removal of Metal Ions from Water

Heavy metal pollution poses a significant threat to the environment and human health. Developing efficient adsorbent materials for removing these contaminants from water is crucial. Sulfur-based polymers derived from inverse vulcanization were found to be promising candidates for the adsorption of several heavy metals from water. In this work, polysulfides bearing β-diketone functional groups are synthesized for the first time through the inverse vulcanization between acetoacetoxyethyl methacrylate (AAEMA) and sulfur. Successful copolymerization and the incorporation of the acetoacetate moiety into the polymer chain are confirmed by NMR, FT-IR, Raman, XPS, XRD, DSC, and TGA analyses. A porous variant of the adsorbent is made using a facile template-assisted method exploring NaCl as a porogen. The porous polymer is analyzed using X-ray micro-CT and SEM to get insights into the internal porous architecture as well as the surface porosity of the adsorbent. Energy-dispersive X-ray (EDAX) and CHNS(O) analyses of the adsorbent reveal a sulfur-rich surface with uniformly distributed oxygen and carbon. Heavy metal adsorption studies of the synthesized polymer are conducted in a multielement solution containing different types of metal ions. The porous adsorbent exhibited remarkable heavy metal chelation properties, with a removal efficiency of 100% for Hg2+ and 72-96% removal for Cr3+, Pb2+, Co2+, Fe3+, Ni2+, Ag+, and Cu2+. The synergistic interplay between the thiol functional groups, polysulfide loops, and the strong binding affinity of the β-diketone moiety and hydroxyl group coupled with the polymer's well-defined porous structure collectively enhances its adsorption capacity toward heavy metal ions. A prototype of an identical porous adsorbent in monolithic form has been constructed. The porous monolith retains all the benefits of porous adsorbent in particulate form while allowing the separation of the adsorbent from the treated water by simply lifting it as a single unit, eliminating the necessity for filtration as is necessary with particulate adsorbents.

An environmental-friendly approach for phytoremediation of zinc ion by Lemnaceae species: process behavior and characterization studies

Phytoremediation is a promising approach grounded in green and sustainable development principles for decontaminating water and soil. Among the studied duckweed species (Spirodela polyrhiza, Wolffia arrhizal, and Lemna minor), S. polyrhiza exhibited the highest zinc removal efficiency of 88.50% by day 7, followed by L. minor and W. arrhiza with removal efficiency of 78.69 and 38.59%, respectively. This study investigated the effects of environmental factors, including initial zinc ion concentration (50, 100, 150, 200, and 250 mg/L), solution pH (pH 5, 6, 7, and 8), and macrophytes mass (5, 10, 15, 20, and 25 g) on the phytoremediation of the zinc ion from synthetic wastewater by S. polyrhiza. The process effectively treated 500 mL of synthetic wastewater containing 100 ppm zinc ion and the process could be enhanced to achieve the removal efficiency of 90% by adjusting the solution pH to slightly acidic (pH 5) and increasing the mass of duckweed to its saturation point (20 g). Excessive zinc intake by duckweed led to chlorophyll reduction, negatively impacting the duckweed growth rate. Scanning electron microscopy (SEM) analysis revealed that the duckweed fronds' surface became uneven after the treatment, with the irregular small particles attached due to cellular damage. The energy dispersive X-ray (EDX) analysis confirmed the successful uptake and accumulation of zinc in the duckweed cells from the synthetic wastewater. In conclusion, duckweed-based phytoremediation demonstrates significant potential for removing zinc ion from wastewater, at low and moderate concentrations.

Assessment of Selected Heavy Metals and Arsenic Concentrations in Wild Boar (Sus scrofa L.) from Papuk Nature Park (Croatia)

The aim of this study was to measure the concentrations of As, Cd, Hg, Pb, Cr, Cu, Fe and Zn in the muscle, liver and kidney of wild boar (Sus scrofa) in Papuk Nature Park, Eastern Croatia. Muscles, liver and kidney of 38 wild boars, up to 3 years of age, were collected and the concentrations of elements were determined by ICP-MS. Cadmium exceeded the permitted levels acceptable for human consumption in 50% of kidney samples (max. = 6.64 mg kg-1), 20% of liver samples (max. = 4.60 mg kg-1) and 43% of muscle samples (max. = 0.672 mg kg-1). Lead exceeded acceptable levels in 63% of liver samples (max. = 0.463 mg kg-1), 51% of kidney samples (max. = 11.8 mg kg-1) and 65% of muscle samples (max. = 9.10 mg kg-1). Mercury concentrations in the liver were higher than allowed in 13% (max. = 0.552 mg kg-1) in kidneys in 27% (max. = 0.484 mg kg-1), and in the muscles in 15% (max. = 0.103 mg kg-1) of cases. Arsenic concentrations in muscles exceeded the permissible value in 30% of cases (max. = 0.286 mg kg-1). The concentrations of Cr, Cu, Fe and Zn did not significantly differ from the values reported in other studies. Median concentrations of Cr, Cu, Fe and Zn ranged as follows: muscle (0.193, 2.94, 44.5 and 20.6 mg kg-1), kidney (0.140, 5.32, 110 and 23.3 mg kg-1) and liver (0.130, 3.71, 278 and 36.0 mg kg-1).

Insights into roles of biochar on migration and accumulation of cadmium in Spartina alterniflora Loisel. -sediment systems and their microbial effects

It is widely recognized that remediating cadmium (Cd)-contaminated sediments using biochar (BC) can significantly influence plant growth and development. However, the efficiency of such remediation often diminishes in field trials compared to greenhouse experiments, likely due to limited comprehension of the BC addition on the plant-sediment-microbe interaction. In this study, a 56-day pot experiment demonstrated that BC application offered (i) enhanced plant root length and biomass, (ii) increased proline content, (iii) improved photosynthetic capacity (e.g., total chlorophyll content), and (iv) mitigated oxidative stress (e.g., decreased the peroxidase (POD) and (CAT) activity, and increased superoxide dismutase (SOD) activity). The increased SOD allowed better scavenging of reactive oxygen species (ROS) in leaves (the primary site of ROS generation), thereby alleviating leaf growth retardation. Notably, the translocation factor of Cd significantly reduced to 0.0034 in BC-amended sediments, under high-Cd toxicity. Qualitative and quantitative analysis identified that BC facilitated the Cd binding ability on the wall of the root cells (up to 85.67 ± 0.88 %) by increasing the adsorption capacity of matrix polysaccharides. Furthermore, the bioavailable Cd proportion in sediments was markedly reduced after BC addition. BC also increased the relative abundances of bacteria, such as Desulfuromonadia and Alteromonadaleswhich were involved in Cd immobilization, and enhanced microbial adaptability to Cd-stress by boosting genetic and environmental information processing functions. The mechanisms on how BC reduced the bioavailable Cd in sediment was dependent on both BC and root presence. These findings demonstrated that BC application is an effective strategy for remediating Cd-contaminated coastal wetlands, offering significant benefits for environmental health and human well-being.

Health Risk for Non-Dietary Children's Exposure to Heavy Metals in Postindustrial Areas in Upper Silesia, Poland

Heavy metal exposure is a significant public health problem, especially among children, who are a particularly vulnerable group. This study investigates the non-dietary exposure of children to lead, cadmium, and zinc and the associated health risk in three selected locations near the former non-ferrous metal smelters. Soil samples were collected from schools, parks, playgrounds, and other recreational places where children spend their free time in three districts of such towns as Katowice, Świętochłowice, and Piekary Śląskie. The contents of Cd, Pb, and Zn in the surface soil samples had the following ranges: 4.09-20.94 mg Cd/kg d.m., 161.70-1027.68 mg Pb/kg d.m., and 577.76-1475.93 mg Zn/kg d.m., respectively. The threshold doses of Cd, Zn, and Pb are 0.001 mg × kg-1 × day-1, 0.3 mg × kg-1 × day-1, and 0.0035 mg × kg-1 × day-1. A significant health risk was estimated as a result of non-dietary exposure of children to lead. The greatest non-cancer health risk in the population of children <6 years of age and in younger school children (<12 years of age) was shown. The problem was especially concerning in the scenario that assumed ingestion of soil particles in the areas most heavily contaminated with lead in the Katowice-Szopienice district. The public health policy should aim to monitor the current exposure of the local population to Pb and educate them on effective prophylactic methods to minimize environmental health risks.

Variability of urinary metal in short-, mid-, long-term periods and its optimal sampling strategy: A novel epidemiological insight to exposure classification

The health effects of metals are well-documented, but relying on single urine samples may inadequately reflect short-, mid-, or long-term exposure, leading to potential misclassification. Variability in urinary metal concentrations and its implications for exposure assessment across different timeframes and epidemiological study designs remain underexplored. Identifying optimal sampling strategies and minimum sample sizes is crucial for exposure assessment of enhancing environmental health research. In a two-year repeated-measures study of healthy adults across 4 visits (2019-2021), first morning void (FMV) urine samples were collected to measure 22 metals. Variance apportionments and intraclass correlation coefficients (ICCs) evaluated metal reproducibility over short-, mid-, and long-term intervals. Surrogate category analyses were conducted to determine the minimum sample size needed for accurate exposure classification. For the long-term variability, four epidemiological scenarios were considered and compared to assess their ability in improving exposure classification. In total, 3,541 FMV samples were collected from 60 participants during all visits. We observed daily variations in metal levels at both the group and individual levels, with fluctuations ranging from several-fold to several tens of times. Co and Zn showed the highest reproducibility, requiring only 2-3 samples to accurately classify exposure across short-, mid-, and long-term periods. Other metals, such as As, Cu, Rb, Sr, Cs, and V, demonstrated good predictive ability, requiring approximately 5 and 10 samples to characterize exposure levels over one month and two years. Conversely, Al, Cr, Sb, and Se consistently failed to meet specificity thresholds of 0.7. Study designs that account for "visits apart" and involve subjects sampling on the same day performed better in exposure classification. Future studies examining the health effects of urinary metals with high temporal variability should carefully consider sampling dates, intervals, and sample size when designing their study to ensure accurate exposure classification across the population.

The role of TPS in promoting the disintegration of LDPE/TPS blends to unravel the degradation mechanism of plastic films

This study explores the role of thermoplastic starch (TPS) in accelerating the degradation of low-density polyethylene (LDPE), a widely used single-use plastic that contributes significantly to environmental pollution. By blending TPS with LDPE, the research focuses on the abiotic degradation of these plastic films under simulated environmental conditions through photo-oxidation via accelerated weathering tests. Over a 10-week period-representing approximately nine months of natural exposure-the films were exposed to light, air, moisture, and heat. The degradation mechanisms were analyzed using Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC), while film disintegration was closely monitored. An additional 8-week seedling experiment assessed the impact of the degraded films on plant growth. Results indicated that LDPE/TPS blends began disintegrating after 6 weeks (approximately 5.4 months), achieving a 36 % degradation rate and reaching complete disintegration at 10 weeks. This surpassed the degradation performance of both standard biodegradable plastics and Oxo-PE. The primary degradation driver was water infiltration, which induced film swelling and contraction, leading to LDPE molecular chain breakdown. These findings provide critical insights into the disintegration mechanisms of LDPE/TPS blends and present a promising approach to accelerating plastic degradation, potentially reducing environmental plastic waste.

Application Progress of Carbon Quantum Dot Composites in Fluorescent Detection of Food Safety

Carbon quantum dots (CQDs) have emerged as promising nanomaterials due to their unique optical properties, excellent biocompatibility, and cost-effectiveness. This review highlights recent advances in CQD-based composite materials and their applications in fluorescence detection, particularly in food safety. Combining CQDs with diverse materials enhances their fluorescence performance, stability, and selectivity, enabling the sensitive detection of various food contaminants. CQD composites offer significant improvements over conventional methods, including lower detection limits, faster response times, and broader applicability. Key areas of focus include the detection of pesticide residues, veterinary drug residues, heavy metal ions, and pathogenic bacteria in complex food matrices. Advanced doping and hybridization strategies, such as heteroatom incorporation, further optimize their optical and chemical properties. These innovations address critical challenges in food safety monitoring, paving the way for more effective and accessible detection technologies. Future developments in CQD composites are expected to expand their applications, ensuring enhanced food quality and public health protection.

Development of a novel low-cost adsorbent Chitosan@EDTA@Cellulose composite to effectively remove Methyl Orange dye from wastewater: Experimental and theoretical investigation

Methyl Orange, a toxic and persistent azo dye, poses significant environmental challenges in aquatic ecosystems. This study investigates the efficiency of a novel Chitosan@EDTA@Cellulose composite, synthesized by linking shrimp-derived chitosan and cactus-derived cellulose using EDTA as a linking agent. Comprehensive characterization techniques, including Fourier-transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and Brunauer-Emmett-Teller surface area analysis, were employed. Under optimal conditions (pH 5, 50 mg/L dye concentration, 55 min, 0.1 g adsorbent), the composite achieved a maximum adsorption capacity of 55.87 mg/g, significantly outperforming chitosan (7.29 mg/g) and cellulose (5.69 mg/g). Adsorption followed the pseudo-second-order kinetic model and the Langmuir isotherm model, with thermodynamic analysis confirming a spontaneous and endothermic process. Competitive adsorption tests demonstrated >90 % removal efficiency despite the presence of interfering ions, attributed to the chelating properties of EDTA and the synergistic effect of the composite structure. Reusability tests showed a slight efficiency decline from 97.8 % to 81.86 % after four cycles. Box-Behnken Design optimization identified adsorbent mass, pH, and dye concentration as key factors in removal efficiency. Density Functional Theory analysis clarified the functional group interactions driving adsorption. These findings underscore the composite's potential as an effective and eco-friendly adsorbent for Methyl Orange removal.

The impact of salinity on heavy metal accumulation in seaweed

Aquatic heavy metal pollution, driven by industrialization and climate change, threatens marine ecosystems through bioaccumulation. Climate-induced salinity fluctuations influence metal speciation and bioavailability in coastal environments. Seaweeds, crucial for nutrient cycling and economic use, exhibit species-specific metal uptake under varying salinity conditions. This study employs bibliometric analysis to examine research trends from 1995 to 2024 on the impact of salinity on metal accumulation in seaweeds. A search conducted on 8 October 2024 resulted in 242 articles, which were then filtered to 28 relevant studies for analysis. Using the Web of Science Core Collection, these articles were analyzed with VOSviewer and Bibliometrix to identify key contributors, collaborations, and research themes. Results reveal a growing academic interest since 2006, with increasing citation counts reflecting global concern over salinity and heavy metal pollution. Significant contributions from Brazil and Portugal, alongside strong European collaborations, highlight regional strengths. Five key themes emerge, encompassing seaweed physiology, biomonitoring, and phytoremediation. Findings indicate that salinity fluctuations significantly affect metal bioavailability and uptake in seaweeds, influenced by species-specific factors, temperature, and pH. This study highlights the need for targeted, site-specific research on diverse seaweed species to effectively manage heavy metal pollution in coastal ecosystems, particularly in light of climate change and industrial activities. Additionally, the research emphasizes the potential of seaweeds as bioindicators and bioremediators in environmental monitoring and pollution management.

Occupational exposure to wildland firefighting and its effects on systemic DNA damage

BACKGROUND

Portugal is among the European Union countries more devastated by forest fires. Wildland firefighters are at the forefront of this battle, facing exposure to a wide range of harmful pollutants. Epidemiological studies have highlighted a potential link between occupational firefighting exposure and several diseases, including cancer. To date, very few studies have explored the biological mechanisms associated with such exposure. The present longitudinal study aims to assess changes in early effect biomarkers following wildland firefighters' occupational exposure to a real wildfire event.

METHODS

Paired blood samples from 59 healthy Portuguese wildland firefighters were collected at two different time points: before wildfire season and after a fire event during wildfire season. Sociodemographic variables (e.g., age, sex) and work-related factors (e.g., years of service) were assessed via a self-reported questionnaire. Levels of early effect biomarkers, such as primary DNA damage and oxidative DNA damage (oxidised purines) were assessed via comet assay. DNA double-strand breaks (DSBs) were evaluated by phosphorylated H2AX (γH2AX). Moreover, hydroxylated polycyclic aromatic hydrocarbon metabolites (OHPAHs) and metal(loid)s were quantified in urine samples. The influence of urinary OHPAHs, urinary metal(loid)s, and other exposure-related factors (e.g., firefighting duration) on changes (Δ) in early effect biomarkers (post-vs. baseline levels) was investigated.

RESULTS

Firefighting activities led to a significant increase in both primary DNA damage and oxidative DNA damage by 22 % (95 % CI: 1.11-1.35; p < 0.05) and 23 % (95 % CI: 1.04-1.45; p < 0.05), respectively. Results from linear regression revealed that per each unit increase of urinary 2-hydroxyfluorene (2-OHFlu) (μmol/mol creatinine), the risk of ⧍ oxidative DNA damage increased by 20 % [FR: 1.20 (1.09-1.32); p < 0.01]. Additionally, each unit increase in urinary cesium (Cs) (μg/L) resulted in a significant 4 % increase in Δ primary DNA damage [FR: 1.04 (1.01-1.06); p < 0.05] and a 3 % increase in Δ oxidative DNA damage [FR: 1.03 (1.01-1.05); p < 0.05]. Post-exposure levels of γH2AX were significantly correlated with urinary 2-OHFlu levels assessed after firefighting (r = 0.30; p < 0.05). Furthermore, exposure duration and reported breathing difficulties during firefighting were significantly associated with increased levels of primary DNA damage.

CONCLUSION

Results obtained provide insights into the potential human health effects of wildland firefighting occupational exposure at the genetic and molecular levels, offering new and important mechanistic data. These findings are crucial for implementing health and safety measures, recommendations, and best practices to mitigate occupational risks and protect the health of wildland firefighters.

Novel green synthesis of Al-Fe₃O₄ nanocomposite for magnetic d-μSPE of Cd(II) from water and food samples

A novel and green nanocomposite (Al-Fe₃O₄) was synthesized and used for the magnetic d-μSPE method for separating and enriching Cd(II) from dried fruit samples. Aluminum foil waste and banana peels were used as the precursors. The green nanocomposite was characterized using FTIR, XRD, and FE-SEM techniques. The characterization results indicated a successful synthesis with active sites for efficient and simple extraction. The method performance showed significant results of low limits of detection (LOD) and quantification (LOQ) of 0.068 and 0.227 μg L-1, respectively. The method demonstrated an efficient extraction time of just 15 s using hand shaking. The optimal parameters were determined as pH 8.0, an adsorbent amount of 5 mg, adsorption and desorption intervals of 15 s and 0.5 min, a sample volume of 30 mL, and an eluent volume of 3.0 mL of 0.1 mol L-1 of HNO₃. The greenness degree of both the synthesis and magnetic d-μSPE methods was evaluated, which achieved high eco-scale and greenness scores of 94 and 0.79, respectively. The detected Cd(II) levels in the food samples were 10.2, 17.0, 27.4, and 18.8 μg kg-1 for dried Granny Smith apples, dried apricots, raisins, and dried kiwi, respectively. The developed method demonstrated exceptional sensitivity and reliability, successfully extracting Cd(II) at ultra-trace levels.

Colpomenia sinuosa extract mitigates lead acetate-induced testicular dysfunctions in male rats

Background

Colpomenia sinuosa brown alga contains pharmacologically active compounds with a wide spectrum of bioactivities; however, few studies have been conducted in the Mediterranean to assess their effects against heavy metal toxicity. One common non-biodegradable contaminant that poses a serious risk to human health and the environment is lead (Pb). This study investigated the efficacy of C. sinuosa extract (CSE) treatment on testicular injury caused by lead acetate (PbAc) in rats.

Methods

The phytochemical, GC/MS profiling, and metal chelation ability of CSE were evaluated. Molecular docking studies were performed using AutoDock Vina. The oral LD50 of CSE was determined by probit analysis. 40 male rats were used as follows: Gp1 as a negative control; Gp2 was treated with 1/10 of CSE LD50 (340 mg/kg b. wt.); Gp3 was administered PbAc solution (100 mg/kg b. wt.); Gp4 was orally administered PbAc as in Gp3 and CSE as in Gp2. All treatments were given daily by gastric tube for 30 days. Body weight changes, biochemical, molecular, and histopathological examinations were investigated.

Results

The results demonstrate that CSE exerted a pronounced metal-chelating activity in vitro and contain promising phytochemicals. The LD50 of CSE was 3,400 mg/kg b. wt. PbAc-treated rats reported significant testicular dysfunction with impaired semen analysis, biochemical, molecular, and histological changes. CSE treatment showed significant palliative effects on these dysfunctions via improvements in antioxidant status, anti-inflammatory properties, and histopathological alterations. Interestingly, CSE treatment modulates the JAK2/STAT3, and NLRP3/Caspase-1 pathways axis in PbAc-injured rats.

Conclusion

This study for the first time investigated the biochemical and molecular mechanisms regarding the effects of CSE treatment on PbAc-induced testicular damage in male rats. CSE showed potential attenuative effect on the testis injury induced by PbAc treatment by targeting JAK2/STAT3, and NLRP3/Caspase-1 pathways. These findings suggest that CSE could be used against the adverse effect of PbAc on male repro-toxicity.

A simple and low-cost electrode based on Nafion-stabilized silver nanoparticles supported on FTO for the electrochemical determination of Pb (II) and Cu (II)

Increasing awareness of the environmental risks posed by heavy metal accumulation in the environment-due to their toxicity and persistence in biological systems-has driven the development of more efficient and accessible detection methods. Conventional techniques, despite their accuracy, are often expensive, time-consuming, and reliant on non-portable specialized equipment. This study presents a novel, low-cost electrochemical sensor using a fluorine-doped tin oxide (FTO) electrode modified with Nafion-stabilized silver nanoparticles (AgNPs) for the rapid and accurate detection of Pb (II) and Cu (II) in water samples. The electrode preparation involved the ultrasonic cleaning of the FTO, followed by its surface modification with Nafion and the electrodeposition of AgNPs. Electrochemical and structural characterization confirmed the advantages of this approach, showing a significant improvement in conductivity and in the active surface area of the electrode, which allowed for the sensitive detection of the target metals. The optimization of analytical parameters, including accumulation time, deposition potential, and pH, facilitated the effective determination of the analytes by differential pulse anodic stripping voltammetry (DPV). The results demonstrated low detection limits of 8.87 ppb for Pb (II) and 3.26 ppb for Cu (II), suitable for in-situ applications in environmental monitoring according to environmental quality standards. The sensor's portability, coupled with its low cost and rapid analysis capability, addresses critical challenges in current monitoring practices and opens new avenues for widespread environmental surveillance in remote areas such as the Andean regions, where heavy metal contamination is a significant concern.

Natural gums-derived hydrogels for adsorptive removal of heavy metals: A review

This review explores advancing and refining hydrogels derived from natural gums for heavy metal ion adsorption, focusing on their efficiency, capacity, and influencing parameters. The high adsorption capacity of these hydrogels, with values reaching up to 384.6 mg/g (Pb2+) and 203.7 mg/g (Cu2+), is linked to functional moieties like -COOH and -OH, which bind to metal ions through electrostatic interactions, exchange of ions, and coordination mechanisms. Adsorption efficiency is governed by conditions such as duration of contact, temperature, and pH. Temperature studies imply that adsorption occurs through an endothermic mechanism, with positive ΔH values and negative ΔG values, validating the spontaneity and efficiency of the process. Adsorption isotherms, including Langmuir and Freundlich models, have shown promising fits, with a high correlation coefficient (r2 > 0.9). The kinetic study reveals that the adsorption follows pseudo-second-order kinetics, implying a chemisorption mechanism. The occurrence of interfering ions (e.g., Na+, Ca2+) can reduce adsorption efficiency, but their impact is minimal at lower concentrations. Overall, gum-based hydrogels provide an eco-conscious and reliable approach for metal ion removal in aqueous solutions, showing potential for large-scale environmental applications. Further studies focusing on improving adsorption capacity and scalability are recommended to enhance their practical utility in wastewater treatment.

Bioaccumulation and Trophic Transfer of Heavy Metals in Marine Fish: Ecological and Ecosystem-Level Impacts

Heavy metal contamination in marine ecosystems poses a critical environmental challenge, with significant implications for biodiversity, trophic dynamics, and human health. Marine fish are key bioindicators of heavy metal pollution because of their role in food webs and their capacity for bioaccumulation and trophic transfer. This review synthesizes current knowledge on the pathways and mechanisms of heavy metal accumulation in marine fish, focusing on factors that influence the uptake, retention, and tissue distribution. We explore the processes governing trophic transfer and biomagnification, highlighting species-specific accumulation patterns and the risks posed to apex predators, including humans. Additionally, we assess the ecological consequences of heavy metal contamination at population, community, and ecosystem levels, emphasizing its effects on fish reproduction, community structure, and trophic interactions. By integrating recent findings, this review highlights key knowledge gaps and suggests future research directions to improve environmental monitoring and risk assessment. Given the persistence and bioavailability of heavy metals in marine environments, effective pollution control strategies and sustainable fisheries management are imperative to mitigate long-term ecological and public health risks.

A New Photoelectrocatalytic Water Purification System for Simultaneous Removal of Organic Pollutants and Heavy Metal Ions in Water

A new photoelectrocatalytic water purification system was investigated by combining photocatalysis and electrochemistry. This configuration achieves simultaneous removal of both organic compounds and inorganic heavy metal ions from water by taking a carbon electrode as the working electrode and another electrode coated with a photocatalyst as the counter electrode. A negative bias potential is imparted onto the working electrode to induce the reduction of heavy metal ions, whereas the photocatalytic degradation of organic pollutants on the counter electrode is amplified via the transfer of photoexcited electrons from the counter electrode to the working electrode. Evaluations conducted in bulk solutions demonstrated that photoelectrocatalysis surpassed photocatalysis by yielding an organic matter degradation efficiency 2.3 times higher, successfully degrading 98% of a 10 μM methylene blue solution within 2 h. Simultaneously, the system realized the recovery of heavy metal ions, including copper, lead, and cadmium. This new photoelectrocatalytic water purification system was further integrated with microchannels, and the testing data affirm the substantial potential for system miniaturization.

Highly selective copper recovery from industrial wastewater via electric field-enhanced ultrafiltration assisted with a picolyl-modified polyelectrolyte

Copper-containing industrial wastewater, characterized by strong acidity, high ionic strength, and various competing metals, presents significant challenges for Cu(II) recovery. To address these issues, an electric field-enhanced ultrafiltration process was developed, assisted with a functional polyelectrolyte with high selectivity for Cu(II). The polyelectrolyte, termed PPEI, was synthesized by grafting picolyl groups onto polyethyleneimine (PEI), enhancing its affinity for Cu(II). The captured Cu(II) was subsequently recovered through electrolysis, demonstrating a sustainable approach for both Cu recovery and PPEI recycling. The synthesis and stability of PPEI were confirmed through infrared spectroscopy, particle size analysis, and dialysis validation, ensuring its reliability in practical applications. The incorporation of picolyl groups onto PPEI enhances its selectivity for Cu(II) via coordination with two amines and four pyridyl groups per copper ion. Under acidic conditions, the maximum loading ratio of copper to PPEI is 1:4 with loading capacity of 119.4 mg/g, which increases to 1.5:4 (i.e., 179.1 mg/g) under neutral to alkaline conditions due to the deprotonation of excess amines. PPEI effectively removes Cu(II) from solutions under various harsh conditions at the loading ratio of 4, maintaining 92-98 % removal efficiency in the presence of high salt concentrations (up to 1 M NaCl) and pH as low as 1, and approximately 85 % removal in solutions with competing metal ions at concentrations up to 50 times higher than Cu(II). Scanning electron microscopy and membrane flux changes indicated that the application of a positive electric field significantly reduces membrane fouling and enhances Cu(II) selectivity. The application of a +0.2 V voltage to the membrane side reduced the flux decline rate by 58 %, significantly improving membrane performance while maintaining a Cu(II) removal efficiency of over 95 %. Electrolysis optimized at a current density of ≤0.004 A/cm2 achieved an 80 % copper recovery while allowing PPEI to be released for recycling. Tests conducted using two types of real industrial wastewater demonstrated a copper removal rate of ∼95 %, with a recovery rate of ∼80 %. This study provides a novel and highly selective approach for the efficient recovery of valuable metals from industrial wastewaters.

Eggshell waste as a bioremoval agent for potentially toxic elements/metals and microbial contaminants from raw water of the Nile River in Egypt

Recently, microbial, and potentially toxic elements/metals (PTEs) contamination of aquatic ecosystems has been increasing in Egypt, owing to the bio-disposal of such pollutants in water effluents. This study focused on using Eggshell waste (ESW) as a bioremoval agent for metals and microbial contaminants from raw water of the Nile river in Egypt which considered the source for life for all Egyptians. ESW was collected from local bakeries in Cairo, Egypt, and prepared for use as bioadsorbent. All raw water samples were treated with prepared ESW and tested for initial and end concentrations of PTEs and microbial load contents. Moreover, Scanning Electron Microscopy with Energy Dispersive X-ray analysis (SEM-EDX) was performed to test ESW characterization properties before and after raw water treatment using ESW. Results obtained by SEM recorded irregular rhombus-like stereo structures with tiny pore structures and lamellar structures with enlarged pore architectures dispersed randomly on the surface before ESW treatment. After ESW treatment, SEM-EDX results indicated a regular and adhesive appearance on the surface of ESW. Moreover, current results revealed that bioremoval efficiency reached 94.4, 64.7, and 51.4% for removing lead, cadmium, and iron, using ESW, respectively. Moreover, ESW was highly effective in eliminating Escherichia coli throughout the first 4 h of contacting and inhibiting 70% of the microbial load incubated at 37 °C, and complete inhibition occurred after 24 h of contacting process. Overall, this study advances knowledge in bioremediation and offers practical solutions for water quality management using organic waste materials.

Indexical methods assessing PTEs distribution in Mahan river command area, central India's coal mining zone

The quality of water can significantly affect the regional water resources due to scarcity of potable water in industrial area. The purpose of this study was to explore potentially toxic trace elements (PTEs) contamination and their seasonal variations in different water sources within the coal mining area of the Mahan River command area, Central India. To achieve this, 96 water samples were collected across two distinct seasons and analysed for PTEs. The results indicate that during the pre-monsoon season, the concentrations of Mn (18%), Cu (4%), Pb (8%), Ni (18%), Cd (2%), Al (4%), Cr (2%), and Fe (30%) exceeded permissible limits. In the post-monsoon season, Mn (15%), Pb (6%), Ni (15%), Cd (2%), Al (15%), Fe (46%) and Ba (4%) surpassed the standards. The multiple groundwater pollution indexical methods further revealed that 14% [Heavy metal pollution index (HPI)], 14% [Heavy metal evaluation index (HEI)], 18% [Contamination index (CI)], 14% [the entropy-weight based HM contamination index (EHCI)] and 20% [Heavy metal index (HMI)] of the samples exceeded permissible thresholds during the pre-monsoon season. Similarly, during the post-monsoon period, 10% (HPI), 10% (HEI), 15% (CI), 15% (EHCI) and 17% (HMI) of the samples were above acceptable limits. The relationship between the pH of water and the total load of dissolved metals is established using Caboi plot, confirming that mine water from mine water from Bhatgaon Underground (UG), Mahamaya UG, and Mahan Opencast (OC) [PR40, PR41, PR42, PR43, PR47, and PR48], surrounding rivers, and groundwater sources, exhibited an "Acid-High Metal" characteristic. This suggests significant contamination from acid mine drainage and mineral dissolution. Apart from the anthropogenic inputs, geogenic and environmental processes are responsible for the current distribution of PTEs and their seasonal variations.

Boron-Doped Diamond Electrodes for Toxins Sensing in Environmental Samples-A Review

Boron-doped diamond electrodes have found applications in the detection, monitoring, and mitigation of toxic chemicals resulting from various industries and human activities. The boron-doped diamond electrode is a widely applicable technology in this field, primarily due to its excellent surface characteristics: minimal to no adsorption, a wide operating potential range, robustness, and high selectivity. These extraordinary properties can be further enhanced through surface termination, which can additionally improve the analytical performance of boron-doped diamond (BDD) electrodes. The high accuracy and precision of the developed methods indicate the broad practical applicability of these electrodes across various sample matrices. Some studies have shown that different strategies can lead to enhanced sensitivity and selectivity, such as modifying the electrode surface (nanostructuring), forming different composite materials based on BDD, or implementing miniaturization techniques. Thus, this review summarizes the recent literature on the electroanalytical applications of BDDE surfaces, with a particular focus on environmental applications.

Performance of Limoniastrum guyonianum in nutrient removal and tolerance in Halloufa Wetland, Algeria

Phytoremediation is an effective and sustainable method for removing pollutants from wastewater. This study investigates the phytoremediation capabilities of Limoniastrum guyonianum, a halophytic Saharan plant species, for excess phosphorus and nitrogen in domestic wastewater. The plants were sourced from the "Halloufa" wetland, a wastewater discharge area in the north of El-Oued, south-eastern Algeria. The research was conducted using pilot-scale circular beds designed for phytoremediation, each with an 18-liter capacity, filled with layers of gravel and a clay-sand mixture. These beds were part of a vertical surface flow system at the National Sanitation Office (ONA) domestic wastewater treatment facility in El-Oued, Algeria. The results demonstrated significant improvements in water quality parameters. Treatment with L. guyonianum reduced pH values from 8.07 to 7.64 and decreased turbidity from 116.25 NTU to 8.87 NTU. The mean concentration values of ammonia, phosphate, and biochemical oxygen demand (BOD5) were reduced by 99.22%, 55.58%, and 78.6%, respectively. The study concludes that L. guyonianum is highly efficient in remediating nitrogen contaminants, effective in reducing phosphorus levels, and capable of lowering biochemical oxygen demand. L. guyonianum presents a nontoxic, eco-friendly, and cost-effective alternative for wastewater treatment in the "Halloufa" wetland, highlighting its potential for application in bioremediation processes.

Kuala Gula Bird Sanctuary, Perak, Malaysia: Status, challenges and future for migratory shorebirds population in the East-Asian Australian Flyway

Birds are an excellent bio-indicator of biodiversity changes. Migratory shorebirds in particular cover a large distances traversing different types of habitats, from the tundra region in the most northern part of the world, to tropical and temperate areas in the southern most area. Kuala Gula, a sanctuary for more than 200 bird species is part of an Important Bird and Biodiversity Areas (IBAs) along the East-Asian Australian Flyway. Despite its importance, the area including its coastline is continuously pressured by anthropogenic activity. As such, there is a need to critically review Kuala Gula's environmental status to highlight its potential, along with understanding the issues and threats particularly to the migratory shorebirds population in the long run. This is important not just to maintain Kuala Gula's relevance as part of the important IBA in the Southeast Asia, but also to ascertain its qualification to meet its recognition's goal. Throughout this review, we found that there are several issues that need to be addressed urgently, particularly ones related to pollution activity. Furthermore, the studies done so far are not coordinated well enough and lack continuity. As such, certain important information is still lacking making the protection and conservation of the area a big challenge. It is concluded that, the stability and sustainability of Kuala Gula's habitats and its coastline is at stake, and there is a hope that this review will help related stakeholders to understand the current issues, and work together effectively to conserve the area.

Potentially toxic elements accumulation in the surface sediment of the Bouregreg estuary, Morocco: Implications for environmental changes and human activities over the last decades

This study investigates the sources, spatiotemporal distribution, contamination levels, and ecological risks of six potentially toxic elements (PTEs) in surface sediments of the Bouregreg Estuary, Morocco, an ecologically significant estuarine system undergoing urbanization and management improvements. The mean PTEs concentrations (mg/kg) were Zn (47.32) > V (30.72) > Pb (17.41) > Cr (14.31) > Cu (9.92) > Cd (1.17). Cd emerged as the most concerning pollutant (up to 2.12 mg/kg), exceeding the background value, showing moderate to strong pollution (Igeo), moderate to very high contamination (CF), and moderate to high ecological risk (ERI). Followed by Pb which showed low to moderate contamination (up to 23.21 mg/kg) according to the CF, correlating with fine, organic-rich sediments near urban areas. Significant seasonal and spatial variations, influenced by anthropogenic pressures and sediment characteristics, were confirmed through principal component analysis and correlation analysis. Historical comparisons indicate an overall improvement in the estuary's ecological health. However, persistent Cd and Pb hotspots emphasize the need for targeted management strategies to safeguard the estuary's ecological integrity and community health.

Integration of physio-biochemical, biological and molecular approaches to improve heavy metal tolerance in plants

Heavy metal toxicity hinders plant growth and development by inducing oxidative stress, decreasing biomass, impairing photosynthesis, and potentially leading to plant death. The inherent defense mechanisms employed by plants, including metal sequestration into vacuoles, phytochelation, cell wall metal adsorption and an enhanced antioxidant system can be improved via various approaches to mitigate heavy metal toxicity. This review primarily outlines plants direct and indirect responses to HM stress and the tolerance mechanisms by which plants combat the toxic effects of metals and metalloids to understand the effective management of HMs and metalloids in the soil system. Furthermore, this review highlights measures to mitigate metal and metalloid toxicity and improve metal tolerance through various physio-biochemical, biological, and molecular approaches. This review also provides a comprehensive account of all the mitigative approaches by comparing physio-biochemical, biological and molecular approaches. Finally, we compared all the mitigative approaches used in monocotyledonous and dicotyledonous to increase their metal tolerance. Although many studies have compared monocot and dicot plants based on metal toxicity and tolerance effects, comparisons of these mitigative approaches have not been explored.

Potential function of plant-growth-promoting endophytic Serratia fonticola CPSE11 from Codonopsis pilosula in phytoremediation of Cadmium ion (Cd2+)

Plant growth promoting rhizobacteria (PGPR) have potential application value in reducing metal accumulation in medicinal plants. The objective of this study was to isolate, characterize and evaluate the effects of endophyte on the growth and metal resistance of Codonopsis pilosula under Cadmium ion (Cd2+) stress. Five endophytic strains were isolated from the root of C. pilosula. Serratia (CPSE11, CPSE12), Enterobacter (CPSE22), Bacillus subtilis (CPSE32), and Microbacterium (CPSE8). Serratia fonticola CPSE11 showed high tolerance to Cd2+. The adsorption of Cd2+ was consistent with the first-order kinetic model, and had a strong correlation with the Langmuir model. The maximum single-layer adsorption capacity (q^m) was 58.47 mg/g (R2 > 0.9). In hydroponic experiments, 107 cfu/mL CPSE11 could effectively alleviate the toxic effect of Cd2+ (0, 5, 10 and 15 mg/L) on C. pilosula. Genomic analysis showed that CPSE11 has genes involved in extracellular polysaccharide (EPS) synthesis, transcription, transport, and metal resistance. These include czcB, cusA/czcA, cusB, and cusC, and genes encoding copper (Cu), silver (Ag), cadmium (Cd), zinc (Zn), and cobalt (Co) efflux pumps. CPSE11 enhances the resistance of C. pilosula to Cd2+ stress by producing siderophores, IAA, ACC, fixing nitrogen and regulating the antioxidant system. CPSE11 alleviates the toxic effect of Cd2+ stress on C. pilosula through EPS fixation, RND-type efflux system and specific translocation of metal tolerance gene family. EPS depend on ABC transporter and Wzx/Wzy pathway to produce. The research will promote the sustainable development of medicinal plants and the application of PGPR in metal stress.

Artificial intelligence based detection and control strategies for river water pollution: A comprehensive review

Water quality (WQ) is a metric for assessing the overall health and safety of water bodies like a river. Owing to the habitation of anthropogenic habitation around its basin, the rivers can become one of the most contaminated water sources globally. The solutions to prevent and remit the impact of river water pollution faces many challenges, one of these entails the management of nonlinear, nonstationary water related dataset. This paper provides a detailed overview of Artificial Intelligence (AI) based techniques and algorithms, highlighting their practical applications in the critical domain of river water pollution diction and control. This review shows models for river WQ simulation from 2019 to 2024, in which over 110 research articles from various databases are analyzed. Key advancements in Machine Learning (ML) and Deep Learning (DL) technologies, including Artificial Neural Networks (ANN), Deep Neural Networks (DNN), Long Short-Term Memory (LSTM), and Random Forest (RF), are highlighted. Besides that, the amalgamation of Internet of Things (IoT) technologies is tested, showing their role in enhancing real-time monitoring and predictive capabilities through continuous data collection and advanced ML/DL models. This review addresses critical challenges and identifies emerging opportunities for future research by showcasing the application of ML, DL, and IoT innovations in surface WQ modeling. It highlights the potential of leveraging advanced technologies to form strengthen solutions for sustainable water resource management and the protection of vital aquatic ecosystems.

Unravelling the developmental toxicity of heavy metals using zebrafish as a model: a narrative review

Developmental toxicity is the disruption of an organism's normal development which may occur in either the parent before conception or in the growing creature itself. Zebrafish (Danio rerio) are being employed as effective vertebrate models to evaluate the safety and toxicity of chemicals because they can breed multiple times in a year so we can observe the toxic effects in the next generation and their development mental stages can be observed and define clearly because their 1 cell stage to prime stage is transparent so we can observe the development of every organ also they have nearly about 80% genetic similarity with humans and shares the similar neuromodulatory structure along with multiple neurotransmitter. The recent research endeavours to examine the harmful outcome of various heavy metals such as cadmium, chromium, nickel, arsenic, lead, mercury, bismuth, iron, manganese, and thallium along with microplastics on zebrafish embryos when subjected to environmentally acceptable levels of every single metal in addition to co-exposure at various points in time. These heavy metals can alter the mRNA expression levels, increase the reactive oxygen species (ROS) generation, decrease antioxidant expression, damage neuronal function, alter neurotransmitter release, alter the expression of several apoptotic proteins, interfere with the different signalling pathways, decrease heat rates, increase malformations like - pericardial oedema, heart oedema, reduce in length tail bending abnormal formation in fins. Thereafter we concluded that due to its involvement in the food chain, it also causes severe effects on human beings.

Assessing air quality impacts of gas stations through heavy metal analysis in dust and employees' scalp hair in Erbil City

This research focused on examining the occurrence of heavy metals, including Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Hg, Pb, and V, within the dust and scalp hair of individuals working at gas stations within Erbil province, as well as residents living in rural areas of Hawraman, away from polluted sources. The measurements of metals were performed in a laboratory environment utilizing an XRF device, including the Thermo Scientific Genius 9000 model. The findings revealed significantly higher concentrations of heavy metals in dust particles and hair samples collected from gas station workers compared to those from clean rural areas. The values derived from the Geo-accumulation index (IGEO) and Pollution Load Index (PLI) suggest that pollution from gas stations ranged from uncontaminated to moderate, reaching severe levels. Specifically, the PLI at gas stations reached an elevated level of 7.02, decreasing to 0.49 in rural areas. A strong connection has been identified between the concentrations of metallic elements in the dust particles and worker's hair samples. Workers with over 22 years of experience had higher metal levels in their hair, while those aged 20-30 had lower levels than those over 55.

Ultrasensitive dual-mode biosensor for photoelectrochemical and differential pulse voltammetry detection of thrombin based on DNA self-assembly

Abnormal levels of thrombin may be associated with various diseases, such as thrombosis and hemorrhagic diseases, making precise detection of thrombin particularly important. Dual signal detection is a method that enhances detection sensitivity and specificity by simultaneously utilizing two different signals. Its primary advantages include improving detection accuracy and reducing false positive rates, making it particularly suitable for clinical analysis and diagnostics. In this work, we developed a dual signal detection method for thrombin based on DNA self-assembly. This design incorporates an X-DNA structure. The two bottom arms of the X-shaped DNA (X-DNA) are designed to bind to CuInS2 nanoparticles via dehydration reactions between amine and carboxyl groups. The two top arms of the X-DNA are designed to hybridize with complementary DNA/glucose oxidase (GOx) and DNA/ferrocene (Fc), respectively. Thrombin triggers the hybridization of DNA/GOx and X-DNA, simultaneously causing the dissociation of DNA/Fc from X-DNA. In the Photoelectrochemical mode, GOx can react with O2 and glucose in the detection solution, resulting in a corresponding decrease in the amount of O2 acting as an electron acceptor and a decrease in the photoelectric signal. In the Differential Pulse Voltammetry mode, due to the decrease in Fc content, the DPV signal also shows a weakening trend. The detection method exhibits a good linear relationship within the range of 10 fM -10 nM, with a detection limit of 6.89 fM and 5.86 fM. The enhanced analytical sensitivity and specificity of dual signal detection technology offer broad prospects for improving disease diagnosis.

Simultaneous Measurements of Nanotrace Amounts of Lead and Cadmium Using an Environmentally Friendly Sensor (An Activated Glassy Carbon Electrode Modified with a Bismuth Film)

This paper shows the fabrication of a new environmentally friendly sensor, an activated glassy carbon electrode with an in situ deposited bismuth film (aGCE/BiF), to determine Cd(II) and Pb(II) at the nanotrace level. The electrochemical activation of the GCE surface was achieved in a solution of 0.1 M phosphate-buffered saline (PBS) of pH = 7 by performing five cyclic voltammetric scans in the range of -1.5-2.5 V at ν of 100 mV/s. The newly developed electrode provides several advantages, such as an increased electron active surface (compared to the glassy carbon electrode) and improved electron transfer kinetics. As a result, the new voltammetric procedure (square-wave anodic stripping voltammetry, SWASV) was established and optimized. With the SWASV method, the following calibration curves and low detection limits (LODs) were obtained for Cd(II) and Pb(II), respectively: 5-100 nM, 0.62 nM, 2-200 nM, and 0.18 nM. The newly prepared method was used to determine the amounts of Pb(II) and Cd(II) in the certified reference material, and the results agreed with the certified values. Moreover, the procedure was successfully applied to determine the Cd(II) and Pb(II) in river samples. The official and standard addition methods validated the measurement results.

Effects of heavy metals on variation in bacterial communities in farmland soil of tailing dam collapse area

Heavy metals are commonly present in polluted soil in mining areas. In this study, we investigated 10 sites of farmland soil in the heavy metal tailing dam collapse area (TDCA) with the dominant phyla Acidobacteriota, Proteobacteria, Bacteroidetes, and Planctomycetes. The heavy metal dam collapse area is a composite contamination area of multiple heavy metals, with Cd, Pb and Zn being the most severely contaminated, and the levels of Hg and Cu exceeding the screening values at some of the sites. The Shannon, Chao1 and ACE indices revealed high microbial diversity but low relative abundance of microorganisms at the severely polluted TDCA1 and TDCA3 sites. The results of redundancy analysis (RDA) showed that Hg (Max = 4.31 mg/kg) and Cu (Max = 100 mg/kg) were important factors affecting soil microbial community in the TDCA compared to other heavy metals. Correlation analysis of heavy metals with microbial communities showed that RB41 (Acidobacteria) was more resistant to high concentrations of Cd, Pb, and Zn pollution. The genera of UTCFX1 (Chloroflxi) and norank_TRA3-20 had strong tolerance to the heavy metal Hg. Cu was significantly negatively correlated with norank_WD2101_soil_group (P < 0.05). Therefore these can be used as indicators for monitoring potential heavy metal contamination. The results can be used to predict the changes in the ecosystem of the mining area to maintain its ecological balance and health.

Perceived Health Impacts of Surface Mining: Local Perspectives from the Mining Communities in Libjo, Dinagat Islands, Philippines

This study examines the perceived health impacts of a mining company on residents of Libjo, Dinagat Islands, Philippines, addressing a critical research gap in understanding the perceived health impacts of mining activities in underrepresented regions. The perceived health impacts of mining operations were examined using a qualitative research approach, employing semi-structured interviews. The interview instrument was developed to investigate how mining company activities impact key health determinants, such as water quality, sanitation, income, employment, infrastructure, education, and women's empowerment. The study was conducted across multiple sites at different distances from the mining area to further investigate the possible distance-based variations. The findings indicate that the mining company has positively impacted several areas, particularly income, employment, infrastructure, education, and women's empowerment. However, there were mixed perceptions regarding water quality and sanitation. The majority of respondents, particularly those who are near the mining sites, perceived a significant positive impact on health service delivery, attributing it to the company's support initiatives. Despite these positive impacts, the community expressed concerns about potential negative environmental consequences, such as air and water pollution, deforestation, land degradation, and noise pollution. This study reveals the complex relationship between mining operations and community health, emphasizing the importance of balancing economic benefits and environmental safety. The study further contributes to a deeper understanding of how mining operations affect the community's health and well-being and their potential distance-based variations.

Selective lead ion sensing via cotton pad-based Na2EDTA capped AuNPs: A smartphone-assisted colorimetric method

Herein, Na2EDTA-capped AuNPs specifically designed for selective smartphone-assisted colorimetric detection are synthesized and characterized. Na2EDTA-capped AuNPs was synthesized and characterized by UV-Visible spectroscopy, ATR, Raman, XRD, SEM and EDX. The calculated activation energy of the produced nanoparticles was 0.2 eV. Using XRD and SEM, the average crystallite size was found to be approximately 25 nm. Only Pb2+ and Cd2+, among the following metal ions: Mg2+, K+, Ca2+, Co2+, Ni2+, Ba2+, Hg+, Bi2+, Pb2+, and Cd2+, caused the AuNa2EDTA solution's hue to shift from reddish in color to blue. Pb2+ and Cd2+ were distinguished using a Na2S solution. Cotton pad with AuNa2EDTA integrated served as the substrate for metal ion adsorption. The GIMP software-supported smartphone was used to implement the color contrast (R) method. In the 10-2000 μM range, a straight line represented the relationship between 1/R and Pb2+ ion concentrations, with a limit of detection (LOD) of 0.28 μM was revealed. Real water sample collected from Rupsa River, Khulna, Bangladesh was tested by the developed colorimetric method to be 80 μM of Pb2+ ion. Combining the prevalence of smartphones and the potential of nanotechnology, a cotton-pad based platform functionalized with AuNa2EDTA may be a ground-breaking method for the detection of Pb2+ ions in various media.

Disposable electronic cigarettes - chemical composition and health effects of their use. A systematic review

OBJECTIVE

Despite the rising popularity of disposable e-cigarettes, little is known about their chemical characteristics, or their impact on users' health. This work attempts to summarize current knowledge about chemical composition and known health effects of disposable e-cigarettes.

METHODS

The literature search was performed in February and March 2024 in Pub Med and Science Direct databases (no time range) by the terms 'disposable electronic cigarette', 'disposable e-cigarette', 'disposable e-cigs', 'cig-a-like e-cigarette', 'cig-a-like electronic cigarette'.

RESULTS

Disposable e-cigarettes contain: nicotine, humectants (propylene glycol, glycerin), flavoring agents (diacetyl, acetoin, triacetin, p-menthone, triethyl citrate, ethyl maltol, 3-hexen-1-ol, methyl anthranilate, α-terpineol, perillartine, benzyl alcohol, vanillin, melonal, methyl dihydrojasmonate, and γ-decalactone), cooling agents (WS-3, WS-23, menthol), carbonyl compounds (acetaldehyde, formaldehyde, propionaldehyde, acetone, acrolein) volatile organic compounds (VOCs) (benzene, ethanol, methanol, styrene, acetylpirazine and 2,3,5-trimethylpyrazine), metals and inorganic compounds (chromium, nickel, manganese, lead, aluminum, and zinc) and reactive oxygen species. Furthermore, there was some evidence of nicotine dependence, risk of cancer and adverse respiratory effects of using disposable e-cigarettes.

CONCLUSIONS

Despite the fact that disposable e-cigarettes contain significantly less toxins compared to combustible cigarettes, they include compounds that are absent in such products that may provide health risk in prolonged usage. In addition, there is a limited number of data on the health effect of disposable e-cigarettes, especially in long time period, for never-smokers. Therefore, due to growing popularity of disposable e-cigarettes among young people, who choose them when initiating nicotine use, further research on their long-term impact of on the users' health is necessary.

Ecological and health risk assessment of Sharm El-sheikh beach sediments, Red Sea coast

Sharm El-Sheikh, located at the southern entrance of the Gulf of Aqaba, is a key tourist destination known for its mild climate and commitment to environmental initiatives, notably hosting COP27 in 2022. This study evaluates heavy metal contamination in beach sediments to assess environmental and human risks. Sampling was conducted at Sharm Port and El-Maya Bay, both popular tourist areas. Sediment samples revealed varying concentrations of Fe, Mn, Zn, Pb, Cu, and Co, all within safe levels. Non-carcinogenic and carcinogenic risks were evaluated through chronic daily intake and hazard indices, revealing that ingestion poses the highest risk among exposure pathways. However, the beach sediments of the study area are generally safe for recreational use by both adults and children according to international standards. Statistical analyses identified low-level natural and anthropogenic sources of contamination, underscoring the need for ongoing environmental monitoring to preserve environmental quality in this vital tourist area and to ensure public health and safety by implementing sustainable waste management practices, regulating tourism activities, and protecting marine ecosystems.

Nano-mediated Management of Metal Toxicity-induced Neurodegeneration: A Critical Review

Heavy metals, omnipresent in the environment, though imperative in trace quantities for human physiology, become a serious health hazard due to their toxicity. Copper, arsenic, lead, iron, and mercury are some examples of the heavy metals responsible for oxidative stress, which is one of the primary factors behind neurodegenerative diseases like Alzheimer's, Parkinson's, and amyotrophic lateral sclerosis. Neurodegeneration is caused by toxicity due to environmental exposure to these toxic substances or genetic variation. Conventional therapies, relying on chelation and antioxidants, suffer from the broader perspective of metal removal in a non-selective manner and poor targeting of the brain. In this respect, treatments based on nanotechnology that employ nanoparticles such as dendrimers, micelles, and liposomes constitute a promising interest in enhancing drug delivery with minimal neurotoxicity. The present review outlines the heavy metals responsible for neurodegenerative diseases, their pathophysiology, management strategies available at present, and the scope of nanotechnology intervention in overcoming shortcomings of conventional therapies. The genetic influence of heavy metals on neurological health is also part of this article.

Assessment of Arthrobacter oxydans Subcellular Structural Stability in Response to Metal Action using Differential Scanning Calorimetry

Despite significant efforts in recent years to clean up the environment, pollution remains a major issue. Bioremediation is the most effective and ecologically friendly way to clean and regenerate chemically polluted environments. Microorganisms' biostabilization of soluble and insoluble forms of hazardous contaminants can be employed to remediate areas contaminated with heavy metals. Understanding how contaminants affect and disrupt intracellular structures and functions is a prerequisite to using microorganisms. The study focuses on the exposure of soil bacteria A. oxydans to Cu (II) and Cs (I). The stability of subcellular structures and intracellular processes leading to cell death or adaptation were assessed using the Differential Scanning Calorimetry (DSC) method. The DSC could lay out in sequence the complex series of denaturation events that take place when cells are heated. The DSC analysis provided the possibility to verify the character of the studied metal action at the whole bacteria cell level at the early stage of metal action.

Enhanced Removal of Cu2+ and Pb2+ Ions from Wastewater via a Hybrid Capacitive Deionization Platform with MnO2/N-Doped Mesoporous Carbon Nanocomposite Electrodes

Integrating MnO2 with carbon is a reliable strategy to improve capacitive deionization (CDI) performance by leveraging the unique properties of both components (i.e., MnO2 and carbon). However, the influences of preliminary functionalization of carbon (e.g., nitrogen doping, KOH activation) and pairing of cathodes and anodes on the CDI performance have yet to be systematically explored. Herein, we prepared a group of MnO2-decorated mesoporous carbon composites with nitrogen as a dopant (i.e., MK-NMCS, K-NMCS, NMCS, and CS), and systematically evaluated the desalination performance of various cathode//anode pairs in a hybrid capacitive deionization (HCDI) for capturing Na+, Cu2+, and Pb2+, respectively. Of all electrodes, the MK-NMCS//K-NMCS pair demonstrates the optimum desalination performance based on salt adsorption capacity (SAC) and cycling stability, offering a SAC of 25.4 mg g-1 and a SAC retention of 102.4% after 50 consecutive charge-discharge cycles at 1.2 V in 500 ppm of NaCl solution. In addition, the MK-NMCS//K-NMCS electrodes also show the maximum ion adsorption capacity (IAC) toward Cu2+ and Pb2+ ions compared to other cathode//anode pairs, attaining an IAC of 37.0 and 30.0 mg Cu2+ per gram electrode materials at 1.2 V in 500 and 200 ppm of Cu2+ solutions, respectively (cf. 32.2 mg of Pb2+ per gram of electrode materials in 200 ppm of Pb2+ solution). Besides, these electrodes exhibit excellent cycling stability when applied in removing each heavy metal ion separately, with IAC retentions of 90.0 and 98.5% after 50 cycles toward Cu2+ and Pb2+ ions, respectively. Mechanical analysis reveals that both heavy metals are likely to be sequestered via capacitive electrosorption by carbon, intercalation with MnO2, and surface complexation at the external surface of the [MnO6] octahedral layers. Our results demonstrated a great potential of the MnO2-decorated N-doped carbon//prefunctionalized carbon pairs, in particular, the MK-NMCS//K-NMCS electrode pair for capturing heavy metal ions via HCDI platforms. Such prefunctionalization and pairing strategies are very promising for screening high-performance composite electrodes for wastewater remediation.