Fish is an excellent source of low-fat protein. Fish contains a lot of omega-3 fatty acids, as well as vitamins D and B2 (riboflavin). The daily consumption of contaminated food, especially fish, is among the primary cause of heavy metals pollution to human health. The aim of the research was to determine the concentration of heavy metals in selected species of fish from the Gulf of Guinea at James Town in Ghana. In tandem with the study\'s objective, samples of different forms of fish, Cassava fish, Flatfish, Redfish, Kingfish, and Silverfish, and sediment were obtained and analyzed for the presence of heavy metals using atomic absorption spectrometer (PerkinElmer®, PinAAcle 900T). The analysis indicated a high concentration of Pb, Cd, and Cr concentrations in fish gills, muscles, and sediment. High lead concentration in Silverfish gills (5.9 mg/kg) and Flatfish gills (2.29 mg/kg) above WHO levels. Cadmium was found in all fish species and sediment except Kingfish. Chromium concentrations were high n Cassava fish (3.10 mg/kg) and Silverfish (4.01 mg/kg) and copper concentrations were absent in the fish species. Arsenic and mercury were also not detected in all fish species and sediment. Manganese concentrations were found in fish and sediment. High cadmium target hazard quotient (0.17-11.60 for adults and 0.24 to 16.24 for children) and cancer risk (0.00-0.04) values in fish samples indicated potential health concerns. The Hazard Index (HI) for the analyzed samples ranged from 0.00 to 12.48 for adults and 0.00 to 17.47 for children. The study suggests that eliminating pollution and other sources of waterbody pollution is crucial to protecting the marine environment and the health of seafood consumers.

Water pollution caused by chromium released from tannery is a serious concern to the environment and public health. Chromium removal from tannery effluent is a crying need before discharging to the surface water. In this study, acrylic acid-grafted sawdust was prepared by Tectona grandis sawdust grafting with acrylic acid employing gamma irradiation in the presence of air and Mohr\'s salt. It was treated with NaOH and the characterization of surface morphology and functional groups of modified sawdust was studied by SEM and FTIR.. The effects of solution pH, adsorbent dosage, adsorption time, and initial Cr(III) ion concentration were investigated by batch sorption studies. The process was found to be pH, temperature and concentration dependent. Langmuir and Freundlich isotherms were applied to realize the adsorption process in depth, and it was found that the Langmuir isotherm model fitted well with experimental data (R2 value of 0.983). The maximum monolayer adsorption capacity of acrylic acid-grafted sawdust for Cr(III) from aquous solution was found to be 21.55 mg g-1 at 25 °C. Pseudo-first-order and pseudo-second-order kinetic models were employed to analyze the kinetics of the process, and it was found that the experimental process followed the pseudo-second-order kinetic model, i.e. chemisorption. This study revealed that acrylic acid-grafted sawdust has a decent potential for the removal of Cr(III) from tannery effluents.

Novel functionalized and/or grafted crosslinked chitosan adsorbents were synthesized and used to remove several toxic heavy metal ions such as nickel, lead, chromium, and cadmium ions from contaminated water. The chitosan biopolymer was functionalized by maleic anhydride (CS_MA) acting also as a crosslinking agent. Glutaraldehyde-crosslinked chitosan (CS_GA) grafted with poly(methyl methacrylate) (CS_MMA) was also synthesized. The synthesized adsorbents were characterized using a variety of analytical techniques such as SEM, TGA, and FTIR, which confirmed their chemical structures and morphology. The adsorption capacity of the adsorbents was analyzed under various conditions of contact time, adsorbent dose, initial concertation, temperature, and pH and evaluated against those of pure chitosan (CS) and the crosslinked chitosan(CS_GA). The ultimate removal conditions were 0.5 g/100 mL adsorbent dose, an initial metal ion concentration of 50 ppm, a temperature of 45 °C, and pH 9. CS_MMA had the highest removal percentages for all metal ions, ranging from 92% to 94%. The adsorption was demonstrated to fit a pseudo-first-order model that followed a Langmuir adsorption isotherm. The results highlight the capacity of the synthesized polymers to efficiently remove major toxic contaminants at low cost from contaminated water, present especially in low-income areas, without harming the environment.

Industrialization has brought many environmental problems since its expansion, including heavy metal contamination in water used for agricultural irrigation. This research uses microbial fuel cell technology to generate bioelectricity and remove arsenic, copper, and iron, using contaminated agricultural water as a substrate and Bacillus marisflavi as a biocatalyst. The results obtained for electrical potential and current were 0.798 V and 3.519 mA, respectively, on the sixth day of operation and the pH value was 6.54 with an EC equal to 198.72 mS/cm, with a removal of 99.08, 56.08, and 91.39% of the concentrations of As, Cu, and Fe, respectively, obtained in 72 h. Likewise, total nitrogen concentrations, organic carbon, loss on ignition, dissolved organic carbon, and chemical oxygen demand were reduced by 69.047, 86.922, 85.378, 88.458, and 90.771%, respectively. At the same time, the PDMAX shown was 376.20 ± 15.478 mW/cm2, with a calculated internal resistance of 42.550 ± 12.353 Ω. This technique presents an essential advance in overcoming existing technical barriers because the engineered microbial fuel cells are accessible and scalable. It will generate important value by naturally reducing toxic metals and electrical energy, producing electric currents in a sustainable and affordable way.

Heavy-metal contamination in agricultural soil, particularly of cadmium (Cd), poses serious threats to soil biodiversity, rice production, and food safety. Soil microbes improve soil fertility by regulating soil organic matter production, plant nutrient accumulation, and pollutant transformation. Addressing the impact of Cd toxicity on soil fungal community composition, soil health, and rice yield is urgently required for sustainable rice production. Vermicompost (VC) is an organic fertilizer that alleviates the toxic effects of Cd on soil microbial biodiversity and functionality and improves crop productivity sustainably. In the present study, we examined the effects of different doses of VC (i.e., 0, 3, and 6 tons ha-1) and levels of Cd stress (i.e., 0 and 25 mg Cd kg-1) on soil biochemical attributes, soil fungal community composition, and fragrant-rice grain yield. The results showed that the Cd toxicity significantly reduced soil fertility, eukaryotic microbial community composition and rice grain yield. However, the VC addition alleviated the Cd toxicity and significantly improved the soil fungal community; additionally, it enhanced the relative abundance of Ascomycota, Chlorophyta, Ciliophora, Basidiomycota, and Glomeromycta in Cd-contaminated soils. Moreover, the VC addition enhanced the soil\'s chemical attributes, including soil pH, soil organic carbon (SOC), available nitrogen (AN), total nitrogen (TN), and microbial biomass C and N, compared to non-VC treated soil under Cd toxicity conditions. Similarly, the VC application significantly increased rice grain yield and decreased the Cd uptake in rice. One possible explanation for the reduced Cd uptake in plants is that VC amendments influence the soil\'s biological properties, which ultimately reduces soil Cd bioavailability and subsequently influences the Cd uptake and accumulation in rice plants. RDA analysis determined that the leading fungal species were highly related to soil environmental attributes and microbial biomass C and N production. However, the relative abundance levels of Ascomycota, Basidiomycota, and Glomeromycta were strongly associated with soil environmental variables. Thus, the outcomes of this study reveal that the use of VC in Cd-contaminated soils could be useful for sustainable rice production and safe utilization of Cd-polluted soil.

Precipitation is an important factor that influences the quality of surface water in many regions of the world. The pollution of stormwater runoff from roads and parking lots is an understudied area in water quality research. Therefore, a comprehensive analysis of the physicochemical properties of rainwater flowing from parking lots was carried out, considering heavy metals and organic micropollutants. High concentrations of zinc were observed in rainwater, in addition to alkanes, e.g., tetradecane, hexadecane, octadecane, 2,6,10-trimethyldodecane, 2-methyldodecane; phenolic derivatives, such as 2,6-dimethoxyphenol and 2,4-di-tertbutylphenol; and compounds such as benzothiazole. To remove the contaminants present in rainwater, adsorption using silica carriers of the MCF (Mesostructured Cellular Foams) type was performed. Three groups of modified carriers were prepared, i.e., (1) SH (thiol), (2) NH2 (amino), and (3) NH2/SH (amine and thiol functional groups). The research problem, which is addressed in the presented article, is concerned with the silica carrier influence of the functional group on the adsorption efficiency of micropollutants. The study included an evaluation of the effects of adsorption dose and time on the efficiency of the contaminant removal process, as well as an analysis of adsorption isotherms and reaction kinetics. The colour adsorption from rainwater was 94-95% for MCF-NH2 and MCF-NH2/SH. Zinc adsorbance was at a level of 90% for MCF-NH2, and for MCF-NH2/SH, 52%. Studies have shown the high efficacy (100%) of MCF-NH2 in removing organic micropollutants, especially phenolic compounds and benzothiazole. On the other hand, octadecane was the least susceptible to adsorption in each case. It was found that the highest efficiency of removal of organic micropollutants and zinc ions was obtained through the use of functionalized silica NH2.

Graphene oxide (GO) is considered as a promising adsorbent material for the removal of metal from aqueous environments. Here, we have used the density functional theory (DFT) approach and a combination of parameters to characterise the interactions of GO with lead (Pb) and cadmium (Cd), i.e., typical harmful metals often found in water. Our model systems consist of a singly and doubly adsorbed neutral (Pb0, Cd0) and charged (Pb2+, Cd2+) atoms adsorbed on the GO nanoparticle of the chemical formula C30H14O15. We show that a single charged metal ion binds more strongly than a neutral atom of the same type. Moreover, to determine the possibility of multiple adsorptions of the GO nanoparticle, two metal atoms of the same species were co-adsorbed on its surface. We found a site-dependent adsorption energy such that when two atoms of the same specie are adsorbed at sites Si and Sj, the binding energy per atom depends on whether one of the two atoms is adsorbed firstly on the Si or Sj sites. Furthermore, the binding energy per atom for the two co-adsorbed atoms of the same specie (i.e., neutral or charged) is less than the binding energy of a singly adsorbed atom. This suggests that atoms may become less likely to be adsorbed on the GO nanoparticle when their concentration increases. We adduce the origin of this observation to be interplay between the metal-metal interaction on the one hand and GO-metal on the other, with the former resulting in less binding for the charged adsorbed metals in particular, due to repulsive interaction between two positively charged ions. The frontier molecular orbitals analysis and the calculated global reactivity descriptors of the respective GO-metal complexes revealed that all the GO-metal complexes have a smaller HOMO-LUMO gap (HLG) relative to that of pristine metal-free GO nanoparticle. This may indicate that although the GO-metal complexes are stable, they are less stable compared to metal-free GO nanoparticles. The negative values of the chemical potentials obtained for all the GO-metal complexes further confirm their stability. Our work differs from previous experimental studies in that those lacked details of the interaction mechanisms between GO, Pb and Cd, as well as previous theoretical studies which used limited numbers of parameters to characterise the GO-metal interactions. Rather, we present a set of parameters or descriptors which provide comprehensive physical and electronic characterisation of GO-metal systems as obtained via the DFT calculations. These parameters, along with those reported in previous studies, may find applications in rational design and high-throughput screening of graphene-based materials for water purification, as an example.

A recent study conducted in Khon Kaen Province, Thailand, evaluated the effectiveness of a technology-assisted intervention aimed at improving water quality and addressing related health issues in communities around key water bodies. The intervention targeted health concerns associated with water contamination, including chronic kidney diseases, skin conditions, hypertension, and neurological symptoms. The study included water quality assessments and health evaluations of 586 residents and implemented a Learning Innovation Platform (LIP) across 13 communities. Results showed significant improvements in the community, including a decrease in hypertension and skin-related health issues, as well as enhanced community awareness and proficiency in implementing simple water quality assessments and treatment. The study demonstrated the value of a comprehensive, technology-driven community approach, effectively enhancing water quality and health outcomes, and promoting greater community awareness and self-sufficiency in managing environmental health risks.

Metals are integral components of the natural environment, and their presence in the food supply is inevitable and complex. While essential metals such as sodium, potassium, magnesium, calcium, iron, zinc, and copper are crucial for various physiological functions and must be consumed through the diet, others, like lead, mercury, and cadmium, are toxic even at low concentrations and pose serious health risks. This study comprehensively analyzes the presence, importance, and consequences of metals in the food chain. We explore the pathways through which metals enter the food supply, their distribution across different food types, and the associated health implications. By examining current regulatory standards for maximum allowable levels of various metals, we highlight the importance of ensuring food safety and protecting public health. Furthermore, this research underscores the need for continuous monitoring and management of metal content in food, especially as global agricultural and food production practices evolve. Our findings aim to inform dietary recommendations, food fortification strategies, and regulatory policies, ultimately contributing to safer and more nutritionally balanced diets.

Canola is the largest self-produced vegetable oil source in China, although excessive levels of cadmium, lead, and arsenic seriously affect its yield. Therefore, developing methods to identify canola materials with good heavy metal tolerance is a hot topic for canola breeding. In this study, canola near-isogenic lines with different oil contents (F338 (40.62%) and F335 (46.68%) as the control) and heavy metal tolerances were used as raw materials. In an experiment with 100 times the safe standard values, the superoxide dismutase (SOD) and peroxidase (POD) activities of F335 were 32.02 mmol/mg and 71.84 mmol/mg, while the activities of F338 were 24.85 mmol/mg and 63.86 mmol/mg, exhibiting significant differences. The DEGs and DAPs in the MAPK signaling pathway of the plant hormone signal transduction pathway and other related pathways were analyzed and verified using RT-qPCR. SAUR36 and SAUR32 were identified as the key differential genes. The expression of the SAUR36 gene in canola materials planted in the experimental field was significantly higher than in the control, and FY958 exhibited the largest difference (27.82 times). In this study, SOD and SAUR36 were found to be closely related to heavy metal stress tolerance. Therefore, they may be used to screen for new canola materials with good heavy metal stress tolerance for canola breeding.