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Infrared pump-probe and two-dimensional infrared (2D-IR) spectroscopies were used to study the vibrational dynamics of a homologous set of trimetallic dodecacarbonyls with increasingly heavy atomic masses in tetrahydrofuran solution. The vibrational lifetimes showed some evidence of the vibrational heavy atom effect (VHAE) but were not consistent across the sample set. Spectral diffusion was measured by 2D-IR spectroscopy to investigate whether the changes produced by the VHAE had influenced other aspects of vibrational dynamics. The triiron species was found to be more dynamic on very fast timescales and may exhibit evidence of a transient bridging CO structure. Centerline slope analysis of the high-frequency CO peak for each complex revealed that the vibrational dynamics were subtly but consistently slowed for the compounds with heavier metal atoms. [ABSTRACT FROM AUTHOR]

Programmable and non-volatile spin-based logic devices have attracted significant interest for use in logic circuits. Realization of logic operations via spin–orbit torque (SOT) driven magnetization switching could be a crucial step in the direction of building logic-in-memory architectures. In this work, we demonstrate experimentally, the realization of four logic operations in a heavy metal/ferrimagnet bilayer structure via SOT switching. We also propose a general scheme for choosing input parameters to achieve programmable logic operations. The bulk and tunable perpendicular magnetic anisotropy and relatively lower saturation magnetization in ferrimagnets are found to make them more energy efficient in performing logic operations, as compared to conventional ferromagnets. Thus, ferrimagnets are promising candidates for use in logic-in-memory architectures, leading to the realization of user-friendly spin logic devices in the future. [ABSTRACT FROM AUTHOR]

Alloying heavy metals (HMs) has been an effective method for enhancing the efficiency of spin–orbit torque. In this study, we demonstrate that Pt100−xWx/Pt/Co/Ta multilayers still maintain perpendicular magnetic anisotropy after high-temperature annealing. Doping tungsten (W) into HM platinum (Pt) at the bottom of a Pt/Co/Ta multilayer significantly increases the spin Hall angle (θ S H ) and reduces the critical switching current density (Jc). The harmonic Hall test results show that the θ S H of the Pt88W12 alloy film is approximately 0.29, which is higher than that of the pure Pt film (0.15). The magnetization switching test reveals that the Jc of Pt94W6 alloy film is approximately 4.892 × 106 A/cm2, which is 51.9% lower than that of the pure Pt film. This study offers a valuable method for reducing power consumption and enhancing the efficiency of related application devices. [ABSTRACT FROM AUTHOR]

First-ever measurements of particulate matter (PM2.5, PM10, and TSP) along with gaseous pollutants (CO, NO2, and SO2) were performed from June 2019 to April 2020 in Faisalabad, Metropolitan, Pakistan, to assess their seasonal variations; Summer 2019, Autumn 2019, Winter 2019-2020, and Spring 2020. Pollutant measurements were carried out at 30 locations with a 3-km grid distance from the Sitara Chemical Industry in District Faisalabad to Bhianwala, Sargodha Road, Tehsil Lalian, District Chiniot. ArcGIS 10.8 was used to interpolate pollutant concentrations using the inverse distance weightage method. PM2.5, PM10, and TSP concentrations were highest in summer, and lowest in autumn or winter. CO, NO2, and SO2 concentrations were highest in summer or spring and lowest in winter. Seasonal average NO2 and SO2 concentrations exceeded WHO annual air quality guide values. For all 4 seasons, some sites had better air quality than others. Even in these cleaner sites air quality index (AQI) was unhealthy for sensitive groups and the less good sites showed Very critical AQI (> 500). Dust-bound carbon and sulfur contents were higher in spring (64 mg g-1) and summer (1.17 mg g-1) and lower in autumn (55 mg g-1) and winter (1.08 mg g-1). Venous blood analysis of 20 individuals showed cadmium and lead concentrations higher than WHO permissible limits. Those individuals exposed to direct roadside pollution for longer periods because of their occupation tended to show higher Pb and Cd blood concentrations. It is concluded that air quality along the roadside is extremely poor and potentially damaging to the health of exposed workers.

The co-occurrence of cadmium (Cd) pollution and selenium (Se) deficiency commonly exists in global soils, especially in China. As a result, there is great interest in developing practical agronomic strategies to simultaneously achieve Cd remediation and Se mobilization in paddy soils, thereby enhancing food quality/safety. To this end, we conducted a field-plot trial on soils having high geological background levels of Cd (0.67 mg kg-1) and Se (0.50 mg kg-1). We explored 12 contrasting fertilizers (urea, potassium sulfate (K2SO4), calcium-magnesium-phosphate (CMP)), amendments (manure and biochar) and their combinations on Cd/Se bioavailability. Soil pH, total organic carbon (TOC), soil available Cd/Se, Cd/Se fractions and Cd/Se accumulation in different rice components were determined. No significant differences existed in mean grain yield among treatments. Results showed that application of urea and K2SO4 decreased soil pH, whereas the CMP fertilizer and biochar treatments increased soil pH. There were no significant changes in TOC concentrations. Three treatments (CMP, manure, biochar) significantly decreased soil available Cd, whereas no treatment affected soil available Se at the maturity stage. Four treatments (CMP, manure, biochar and manure＋urea＋CMP＋K2SO4) achieved our dual goal of Cd reduction and Se enrichment in rice grain. Structural equation modeling (SEM) demonstrated that soil available Cd and root Cd were negatively affected by pH and organic matter (OM), whereas soil available Se was positively affected by pH. Moreover, redundancy analysis (RDA) showed strong positive correlations between soil available Cd, exchangeable Cd and reducible Cd with grain Cd concentration, as well as between pH and soil available Se with grain Se concentration. Further, there was a strong negative correlation between residual Cd/Se (non-available fraction) and grain Cd/Se concentrations. Overall, this study identified the primary factors affecting Cd/Se bioavailability, thereby providing new guidance for achieving safe production of Se-enriched rice through fertilizer/amendment management of Cd-enriched soils.

Castellaniella species have been isolated from a variety of mixed-waste environments including the nitrate and multiple metal-contaminated subsurface at the Oak Ridge Reservation (ORR). Previous studies examining microbial community composition and nitrate removal at ORR during biostimulation efforts reported increased abundances of members of the Castellaniella genus concurrent with increased denitrification rates. Thus, we asked how genomic and abiotic factors control the Castellaniella biogeography at the site to understand how these factors may influence nitrate transformation in an anthropogenically impacted setting. We report the isolation and characterization of several Castellaniella strains from the ORR subsurface. Five of these isolates match at 100% identity (at the 16S rRNA gene V4 region) to two Castellaniella amplicon sequence variants (ASVs), ASV1 and ASV2, that have persisted in the ORR subsurface for at least 2 decades. However, ASV2 has consistently higher relative abundance in samples taken from the site and was also the dominant blooming denitrifier population during a prior biostimulation effort. We found that the ASV2 representative strain has greater resistance to mixed metal stress than the ASV1 representative strains. We attribute this resistance, in part, to the large number of unique heavy metal resistance genes identified on a genomic island in the ASV2 representative genome. Additionally, we suggest that the relatively lower fitness of ASV1 may be connected to the loss of the nitrous oxide reductase (nos) operon (and associated nitrous oxide reductase activity) due to the insertion at this genomic locus of a mobile genetic element carrying copper resistance genes. This study demonstrates the value of integrating genomic, environmental, and phenotypic data to characterize the biogeography of key microorganisms in contaminated sites.

Sewage sludge is an important soil conditioner, and source of nutrients with a potential for use in agriculture. However, such benefit needs to be weighed against the risks due to the presence of heavy metals, and other substances that may endanger human health, plants, soil and the ecosystem. This research had the objective of evaluating the agricultural potential of sewage sludge together with the risks that may be present in use. Samples of sewage sludge from seven wastewater treatment plants in Eswatini were analyzed for selected physical and chemical parameters, and heavy metal concentrations using commonly established laboratory procedures. The analysis results indicated that, sludge samples exhibited high organic matter content, cation exchange capacity, macro nutrients such as nitrogen and phosphorus and micro nutrients (trace metal elements) needed for plant growth. Anaerobically digested sludge samples showed higher carbon to nitrogen ratio because of biomass loss in the form of methane and carbon dioxide. The heavy metal concentrations are all within safe limits except the sludge from Matsapha area that had levels of chromium, and nickel above regulatory limits. With respect to their heavy metal contents, most of the sludge samples would qualify as Class A sludge ready to be used as organic fertilizer for agriculture without regular monitoring of heavy metals in the soil to which they are applied. The study results indicated the importance of sewage sludge for their agricultural potential through supplementation of both micro and macro nutrients needed for plant growth, for improving the soil properties such as water holding capacity and permeability, through the increase of organic matter content, and retention of nutrients due to the high cation exchange capacity. All these benefits are realized with sewage sludge being a lower cost alternative to commercial fertilizers. Moreover, the low concentration of heavy metals present in the sludge presents lower risk that may arise in the course of utilizing the sludge as agricultural supplement. Key words: Agriculture, fertilizer, heavy metals, nutrient, sewage, sludge, nitrogen, phosphorous, INTRODUCTION Sewage sludge is known to contain nutrients and trace elements that are required for growing plants. It is also a good soil conditioner that offers comparative advantages over mineral [...]

Odontocetes obtain nutrients including essential elements through their diet and are exposed to heavy metal contaminants via ingestion of contaminated prey. We evaluated the prevalence, concentration, and tissue distribution of essential and non-essential trace elements, including heavy metal toxicants, in tissue (blubber, kidney, liver, skeletal muscle, skin) and fecal samples collected from 90 odontocetes, representing nine species, that stranded in Georgia and Florida, USA during 2007-2021. Samples were analyzed for concentrations of seven essential (cobalt, copper, iron, manganese, molybdenum, selenium, zinc) and five non-essential (arsenic, cadmium, lead, mercury, thallium) elemental analytes using inductively-coupled plasma mass spectrometry. Rissos dolphins (Grampus griseus) and short-finned pilot whales (Globicephala macrorhynchus) had the highest median concentrations of mercury, cadmium, and lead, while dwarf sperm whales (Kogia sima) had the lowest. Adult pygmy and dwarf sperm whales that stranded in 2019-2021 had higher concentrations of arsenic, copper, iron, lead, manganese, selenium, thallium, and zinc compared to those that stranded in 2010-2018, suggesting an increasing risk of exposure over time. The highest concentrations of many elements (e.g., cadmium, cobalt, copper, manganese, molybdenum, thallium, zinc) were in fecal samples, illustrating the usefulness of this noninvasively collected sample. Aside from fecal samples, hepatic tissues had the highest concentrations of iron, manganese, mercury, molybdenum, and selenium in most species; renal tissues had the highest concentrations of cadmium; skin had the highest concentrations of zinc; and copper, arsenic, and lead concentrations were primarily distributed among the liver and kidneys. Phylogenetic differences in patterns of trace element concentrations likely reflect species-specific differences in diet, trophic level, and feeding strategies, while heterogeneous distributions of elemental analytes among different organ types reflect differences in elemental biotransformation, elimination, and storage. This study illustrates the importance of monitoring toxic contaminants in stranded odontocetes, which serve as important sentinels of environmental contamination, and whose health may be linked to human health.

The demolding process in micro-injection molding constitutes a critical phase, exerting a decisive influence on the quality of polymer microstructures. In this study, the demolding forces of PMMA microfluidic chips were measured under different demolding temperatures, packing pressures, and demolding speeds by using pure nickel (Ni) mold insert. The dimensional deviations of the microchannels with different aspect ratios were analyzed. In addition, the effect of mold insert modification on the demolding force was further analyzed. The results showed that the effect of demolding temperature on the demolding force was the most significant, and the peak demolding force decreased with the decrease in temperature. The width of the microchannels increased and the depth decreased after demolding, while the opposite results were observed for the micro-mixing structures. However, the dimensional deviation of the micromixing structures was larger than that of the microchannels. Using the optimal molding parameters, the peak demolding force could be reduced from 114.0 N at 110[degrees]C to 47.0 N, a decrease of 58.8%. It is noteworthy that, when the microchannel was narrower than 100 [micro]m, achieving precise replication of microchannel dimensions became progressively more challenging as the microchannel width decreased. Using the Ni-W[S.sub.2] mold insert with low surface energy and low friction coefficient, the demolding force could be further reduced by 38.3%. The effect of the molding quality of microfluidic chip microstructures on the mixing performance of heavy metals was demonstrated by micro-mixing experiments. Highlights * Demolding temperature crucially affects microstructure dimensions. * Optimal parameters and modified mold insert reduce demolding force by 38.3%. * Dimensional deviation increases with the increase of microchannel aspect ratio. * Optimized microfluidic chip enhances [Co.sup.2+] chemiluminescence by 6.42%. KEYWORDS demolding force, dimensional deviation, microfluidic chip, micro-injection molding, microstructure, 1 | INTRODUCTION Microfluidics is extensively employed in various fields such as biotechnology, chemical analysis, and medical diagnosis. (1,2) Microfluidic chips, which integrate an array of microstructures including microchannels, microcolumns, [...]

Heavy metals, pharmaceuticals, microplastics, dyes, and radionuclides in wastewater increasingly threaten environmental sustainability. Metal‐organic frameworks (MOFs) are versatile materials for mitigating these contaminants through efficient detection, capture, adsorption, and degradation. These crystalline structures, formed by combining metal ions with organic ligands, offer high surface area, tailored porosity, reproducibility, and robust chemical stability. This review compiles recent advancements in MOFs for pollutant removal, highlighting innovations in selective adsorption mechanisms for heavy metals, functionalized MOFs for pharmaceutical and microplastic removal, and enhanced photocatalytic degradation for dyes. Unique to this review is the integration of recent innovations such as ion exchange capabilities and photocatalytic degradation under visible light, addressing advanced applications that significantly enhance pollutant removal efficiency that other reviews have not covered comprehensively. The review also cites our group's recent work on a curcumin‐immobilized zeolitic imidazolate framework‐8 (Cmim@ZIF‐8) nanoprobe, demonstrating high selectivity for Fe2+ ions in water (detection limit: 7.64 μM) and its applicability in live‐cell imaging of HepG2 cells. Advanced techniques like density functional theory (DFT) simulations are employed to elucidate adsorption and degradation mechanisms, bridging theoretical insights with experimental findings. By critically evaluating these developments, the review identifies promising avenues for optimizing MOF design and advancing effective water treatment solutions. [ABSTRACT FROM AUTHOR]

Ambient PM2.5 and their toxic components were measured in six ecologically different districts of India. Cadmium (Cd), arsenic (As), chromium (Cr), copper (Cu), zinc (Zn), molybdenum (Mo), and lead (Pb) were present in most of the PM2.5 samples analysed. A new heavy metal exposure index (HEI) was formulated based on weighted geometric mean approach using substance toxicity points given by Agency for Toxic Substance and Disease Registry (ATSDR). The proposed HEI differentiates toxic PM2.5 and helps screen unhealthy air pollution regions, and can thus assist in forming adequate public health policy. [ABSTRACT FROM AUTHOR]

With the excavation of landfill sites, the disposal and reduction of organic-rich soils with high proportions of heavy metals have become urgent issues. This study focuses on the pollution characteristics and ecological risks associated with heavy metals in the humus soil of a municipal solid waste (MSW) landfill. The results indicate that the concentrations of heavy metals in the humus soil followed the sequence of Cu > Zn > Cr > Pb > Ni > As > Cd > Hg, and Cu and Cd exhibited the highest exceedance multiples. Except for Cr, the concentrations of the heavy metals in the humus soil were higher than those in combustible components, with a strong Hg correlation. Heavy metal forms indicate varying degrees of mobility and stability; Cr, As, Hg, and Pb were stable, while Ni, Cd, Cu, and Zn showed higher mobility. The results of the principal component analysis reveal that heavy metals primarily originate from industrial and agricultural waste. Finally, the geoaccumulation index of the metals indicated that Cu, Zn, Cd, and Pb exhibited severe contamination. Most importantly, Cd posed the greatest environmental risk as it has the highest effective content, bioavailability, and mobility. This study provides a scientific foundation for mitigating heavy metal pollution in the humus soil of landfill sites. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the potential of replacing fly ash (FA) with bauxite tailing (BT) slurry for geopolymer synthesis and investigate the long-term leaching behaviour of BT slurry/FA geopolymers (BFGs) for heavy metal immobilisation. The mechanical properties and heavy metal immobilisation efficiency of BFGs were tested, and numerical simulations were conducted to assess their environmental impact as a backfill material. The results showed that the incorporation of 5 Wt.% BT increased the early compressive strength of the geopolymer without any additional treatment. A small quantity of Cu2+ improved the mechanical strength, while excess heavy metals harmed the geopolymer. Heavy metal immobilisation efficiency decreased with increased heavy metal addition and exceeded 99.9% for Pb2+ and Cu2+ when simulating acid rain leachate. The modified Elovich equation described the leaching kinetics of Cu2+ well, and the leaching rate decreased with time. Numerical analysis indicated that Cu2+ leaching from landfill leachate occurred in three phases, with an initial increase followed by a gradual decrease, stabilisation, and diffusion into the surrounding soil layer. This study provides insight into the material's long-term stability and environmental performance, offering a scientific basis for relevant engineering applications. Highlights: Direct utilisation of unprocessed tailing slurry to synthesise geopolymer. The leaching pattern of Pb2+ and Cu2+ under acidic conditions was explored. The modified Elovich equation effectively describes the leaching kinetics of Cu2+. The environmental impact of bauxite tailings slurry-based geopolymers was evaluated. [ABSTRACT FROM AUTHOR]

In recent years, heavy metals derived from several anthropogenic sources have both direct and indirect detrimental effects on the health of the environment and living organisms. Whole-cell bioreporters (WCBs) that can be used to monitor the levels of heavy metals in drinking and natural spring waters are important. In this study, whole-cell arsenic bacterial bioreporters were immobilized using polycaprolactone (PCL) electrospun fibers as the support material. The aim is to determine the properties of this immobilized bioreporter system by evaluating its performance in arsenic detection. Within the scope of the study, different growth media and fiber immobilization times were tested to determine the parameters affecting the fluorescent signals emitted by the immobilized bioreporter system in the presence of two dominant forms of arsenic, namely arsenite (As(III)) and arsenate (As(V)). In addition, the sensitivity, selectivity, response time, and shelf-life of the developed bioreporter system were evaluated. As far as the literature is concerned, this is the first study to investigate the potential of using PCL-electrospun fiber-immobilized fluorescent bacterial bioreporter for arsenic detection. This study will open new avenues in environmental arsenic monitoring. [ABSTRACT FROM AUTHOR]

With the increasing shortage of land resources and the aggravation of soil pollution in mining areas, the remediation of soil in abandoned mining areas has gradually attracted people's attention. The remediation of heavy metal contaminated soil in mining areas is the key to reduce the harm of heavy metals to the environment and human health. In this study, municipal sludge and phytoremediation technology were combined to investigate the migration and transformation of heavy metals at the soil-plant interface in improved mining areas through indoor pot experiments. The results showed that heavy metals in non-rhizosphere soil entered the rhizosphere environment with the growth of plants, leading to the increase of heavy metal content in rhizosphere soil. The cumulative amounts of Cu, Zn, Pb and Cd were 1299.32, 832.10, 347.89 and 71.34 mg/kg, respectively. The content of oxidized Cu and Zn decreased with increasing planting days, while the oxidized Pb and Cd showed an increasing trend. Under acidic conditions, H+ is easy to compete with heavy metal ions for exchangeable positions in the clay mineral layer, so that the reducible heavy metals are easy to be converted into exchangeable states. In this paper, the effects of various factors on the distribution of heavy metals were discussed by adjusting soil pH, adding humic acid and root exudates, so as to analyse the migration and transformation mechanism of heavy metals at the soil-plant interface, and provide a reliable theoretical basis for soil remediation in mining areas. [ABSTRACT FROM AUTHOR]

Background: Malay herbal medicine (MHM) is a popular medication and supplementation among Malaysian mothers during pregnancy and postpartum. It is expected to improve the baby's health, increase breastmilk production, promote slimming and uterine involution, and improve the mother's general health. Recent increases in reports of heavy metal contamination have raised safety concerns. Objective: This pilot exploratory study employed a comparative cross-sectional design to investigate the types of MHM ingested during pregnancy and postpartum, their possible heavy metal contamination and associated health risks. Method: This study involved 167 healthy postpartum Malay women. Findings: MHM consumption was significantly associated with the mother's number of pregnancies and children (p < 0.05) as well as her pre-pregnancy weight (p < 0.05). Mothers who consume MHM were twice as likely (95% CI 1.077–3.963) to experience threatened abortion. Heavy metals were detected in the three most widely consumed MHM samples. The mean concentration of heavy metals in these samples were 47.44 ± 67.74 μg/kg for As, 25.34 ± 2.48 μg/kg for Cd, 3685.87 ± 5683.36 μg/kg for Cr and 194.33 ± 195.19 μg/kg for Pb. The calculated non-carcinogenic hazard health risks (HQ) and health index (HI) were less than one, suggesting no adverse health impacts under the exposure conditions studied. Conclusion: While the HQ and HI values indicate no immediate health risks, the potential transfer from mother to foetus during pregnancy and from mother to infant during breastfeeding warrants further investigation. Additional studies are essential to confirm our findings and monitor the health of mothers and infants. [ABSTRACT FROM AUTHOR]

Heavy metal pollution has been a serious risk in the Indigenous Zinc Smelting in Northwest Guizhou, China. Long-term open-air stacking of waste slag has also led to a great increase in the heavy metal reactivity under suitable environmental conditions after leaching, thus continuously migrating to the surrounding groundwater, surface water, and soil. A substantial amount of mining slag has been left behind, due to outdated technology and extensive production. Therefore, it is very urgent to clarify the contamination status of heavy metals in the soil, water bodies, and sediments in the areas, particularly with the concentrated distribution of Indigenous Zinc Smelting slag and their potential ecological risks, in order to protect the local land and water resources for the food safety and public health. This study focused on an 8 km2 area with a relatively wide distribution of Indigenous Zinc Smelting slag from traditional smelting areas. Human pollution sources were avoided to collect the surface soil samples within a grid of 1/9 km2. The background levels of heavy metals in surface soils were established over the region. Some samples were collected from the smaller watersheds, including surface soil, sediment from water systems, leachate, mine slag, and water bodies, according to the hydrogeological and topographical conditions. Additionally, the samples of deep soil profile were gathered from the site, where the largest amount of mine slag was stored for the longest time. The content of heavy metals and pH value were measured in various samples using the single-factor pollution index, Nemerow comprehensive pollution index, and potential ecological risk index. The spatial distribution and pollution status of heavy metals were analyzed in different media. The results show that the surface soil in the study area was mainly acidic, where the average contents of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn were 23.54, 3.20, 208.78, 193.02, 0.07, 91.41, 315.80, and 479.13 mg/kg, respectively. Except for Hg and pH, the contents of the rest elements were higher than the background value of surface soil in the Bijie region. The contents of As, Cd, Cr, Cu, Ni, Pb, and Zn exceeded the national environmental background values of surface soil. The overall slag was neutral with the average contents of As, Cd, Cu, Hg, Pb, and Zn higher than the average value of surface soil in the study area. Especially Pb, the raw materials used in local traditional zinc smelting were imported the lead-zinc ores. The soil profile samples show that the heavy metals were mainly concentrated in the surface soil of 0-20cm, whereas, the heavy metals in deep soil were mainly controlled by geological background and primary soil. The highest contents of As, Cd, Cu, Pb, and Zn in small watershed sediments were 274, 11.90, 488, 2340, and 2580 mg/kg, respectively, all of which were located in the central area of traditional zinc smelting slag. The highest contents of Cr, Cu, Ni, Pb, and Zn in the surface water of a small watershed were distributed downstream of the slag concentrated distribution area, which were 43.60, 64.90, 15.70, 226.00, and 223.00 mg/L, respectively. Only Ni was slightly higher than the content of slag leachate in groundwater. The contents of the rest elements were lower than those in the leachate. Single-factor evaluation was performed on the pollution of heavy metals in the surface soil. The Cd and Cu shared the highest proportion of pollution, with the Cd in the widest range of pollution. The Nemerow comprehensive pollution index for heavy metals in small watershed sediments was heavily polluted by As, Cd, Cu, Pb, and Zn. The very strong potential ecological risk was only found in the central part of the traditional Indigenous Zinc Smelting slag distribution area. The Nemerow comprehensive pollution index of heavy metals in small watershed water bodies was severely polluted; The medium to very strong potential ecological risk areas were concentrated in the traditional zinc smelting slag distribution areas. There was an extremely uneven distribution of As, Cd, Pb, and Zn in the surface soil with the coefficients of variation exceeding 1.5, indicating the strong human factors. About 12.5% of the study area shared a strong ecological risk, which was mainly distributed around the waste dump site of the Indigenous Zinc Smelting plant. As such, the Indigenous Zinc Smelting slag posed a significant impact on the surrounding ecology. The pollution range of heavy metals was concentrated mainly within 2500 m in the water sediments in the small watershed; The impact of slag on groundwater was less than that on surface water, due to the restriction from the hydrogeological conditions. Overall, the pollution areas of the zinc smelting slag in the study area were mainly distributed around the centralized storage area of the slag, with a relatively limited range of impacts. [ABSTRACT FROM AUTHOR]

The content of heavy metal Cu in soil is an important indicator for assessing soil quality. However, soil hyperspectral data contain a large amount of redundant data, which can affect the effectiveness of spectral modelling. To address this problem, a combined method based on Whale Optimization Algorithm and Successive Projection Algorithm (WOA-SPA) is proposed to select the characteristic bands. And a prediction model of soil heavy metal Cu content was constructed using the partial least squares method. The experimental results show that: (1) The prediction accuracy of soil Cu content using the WOA-PLSR model was higher than that of the SPA-PLSR model, with RPD increased by 0.229, the R2 increased by 0.07, and RMSE decreased by 0.354. (2) Running the WOA and WOA-SPA combination algorithms 30 times respectively to prove the stability of the algorithms, the prediction accuracy of the model constructed based on the WOA-SPA combination algorithm is better than that of the model constructed based on the WOA algorithm as a whole. (3) Compared with the WOA or SPA algorithm alone, the prediction model constructed based on the WOA-SPA algorithm has a better prediction performance, with RPD of 2.259, R2 of 0.804, and RMSE of 2.396 for the prediction set. (4) Comparing the spatial distribution maps of the measured and predicted values, it can be observed that the spatial distribution between the predicted Cu content values based on the combined WOA-SPA algorithm and the measured Cu content values are basically consistent. This study indicates that the WOA-SPA-PLSR model has good stability and prediction accuracy for the prediction of Cu content in soil, which is of great practical significance for the rapid and accurate estimation of heavy metal Cu content in soil. HIGHLIGHTS: A novel dimensionality reduction method based on WOA-SPA was proposed. The WOA-SPA-PLSR model was constructed, which can accurately and quantitatively predict the content of heavy metal Cu in soil. The characteristic band selected by the WOA-SPA combination algorithm accounts for 2.79% of the full band, effectively reducing the dimensionality of soil hyperspectral data. Comparing the spatial distribution maps of measuredsoil Cu content and predicted soil Cu content,it can be found that the spatialdistribution of thetwois basically consistent. This shows that the WOA-SPA-PLSR model can effectively predict the spatialdistribution of soil Cu content in this area. [ABSTRACT FROM AUTHOR]

• The ash melting temperature decreased on the influence of Na2O. • An appropriate ratio of MBA and MFA can effectively reduce the Cr leaching level. • The stabilization of heavy metals was enhanced when vitreous content exceeded 97.7%. • The solidification effect on Mn and Zn was readily apparent. Medical waste incineration ash (MWIA) has significant concentrations of heavy metals, dioxins, and chlorine that, if handled incorrectly, might cause permanent damage to the environment and humans. The low content of calcium (Ca), silicon (Si), and aluminum (Al) is a brand-new challenge for the melting technique of MWIA. This work added coal fly ash (CFA) to explore the effect of melting on the detoxication treatment of MWIA. It was found that the produced vitrification product has a high vitreous content (98.61%) and a low potential ecological risk, with an initial ash solidification rate of 67.38%. By quantitatively assessing the morphological distribution features of heavy metals in ashes before melting and molten products, the stabilization and solidification rules of heavy metals during the melting process were investigated. This work ascertained the feasibility of co-vitrification of MWIA and CFA. In addition, the high-temperature melting and vitrification accelerated the detoxification of MWIA and the solidification of heavy metals. [ABSTRACT FROM AUTHOR]

[Display omitted] • High concentrations of pollutants were present in runoff flowing through tailings. • Metals have strong migration ability in TCLP environment. • The cumulative release of Mn, Zn, Co, and Ni was larger. • Seepage affects the chemical fraction of metals in tailings. • Mn has posed a serious threat to groundwater. The continued growth in demand for mineral resources has led to a large amount of mining wastes, which is a major challenge in the context of carbon neutrality and climate change. In this study, runoff migration, batch leaching, and column experiments were used to investigate the short-, medium-, and long-term leaching of heavy metals from legacy tailings, respectively; the cumulative metal release kinetic equations were established, and the long-term effects of tailings leaching were verified by HYDRUS-1D. In runoff migration experiments, surface dissolution of tailings and the co-migration of adsorbed soil particles by erosion were the main carriers in the early stages of leachate formation (Mn ∼ 65 mg/L and SO 4 2- up to 2697.2 mg/L). Batch leaching tests showed that the concentration of heavy metals in soil leached by acid rain were 0.1 ∼ 22.0 μg/L for Cr, 0.7 ∼ 26.0 μg/L for Cu, 4.8 ∼ 5646.0 μg/L for Mn, 0.3 ∼ 232.4 μg/L for Ni, and 1.3 ∼ 448.0 μg/L for Zn. The results of column experiments indicated that some soluble components and metals with high mobility showed a significant decreasing trend at cumulative L/S ≤ 2. Additionally, the metals have higher leaching rates under TCLP conditions, as shown by Mn > Co > Zn > Cd > Ni > Cu > Pb > Cr. The fitting results of Langmuir equation were closer to the cumulative release of metals in the real case, and the release amounts of Mn, Zn, Co, and Ni were higher with 55, 5.84, 2.66, and 2.51 mg/kg, respectively. The water flow within tailings affects the spatial distribution of metals, which mainly exist in relatively stable chemical fractions (F3 + F4 + F5 > 90 %) after leaching. Numerical simulation verified that Mn in leachate has reached 8 mg/L at a scale of up to 100 years. The research results are expected to provide technical basis for realizing the resource utilization of tailings in the future. [ABSTRACT FROM AUTHOR]

A long-term sustainable tungsten cathode-solution anode glow discharge (SAGD) source for atomic emission spectrometry was developed for the determination of heavy metal elements. The tungsten cathode of this source was cooled by a compact refrigeration semiconductor, which is simple in design and able to operate at atmospheric pressure for long periods. When the equipment operates at its optimal conditions (75 mA discharge current, 2.0 mm discharge gap, 3.8 mL min−1 flow rate, and solution pH value of 2.0), the detection limits of Ag (338.24 nm), Cd (228.80 nm), Hg (253.66 nm), Pb (368.28 nm), Tl (337.52 nm), and Zn (213.79 nm) were explored, and the values were 0.030, 1.7, 7.2, 17, 0.24, and 25 μg L−1, respectively. The interference of coexisting ions in water, such as K+, Ca2+, Na+, Mg2+, and Li+, on the analytical performance of the solution anode glow discharge-atomic emission spectrometry (SAGD-AES) for Cd, Hg, Pb, and Zn were investigated. The results showed that coexisting metal ions' interferences are insignificant. The SAGD-AES system was successfully applied for analyzing water samples from the Yangtze River and Baixi River, and its accuracy and practicality were verified by comparison with inductively coupled plasma-optical emission spectrometry (ICP-OES) results. [ABSTRACT FROM AUTHOR]

Hexavalent chromium (Cr(VI)) is a highly toxic form of chromium, which can be found in industrial effluents from various sectors, such as the metallurgical, tanning, and pigment industries. The presence of Cr(VI) in the environment is a concern due to its negative effects on human health and the ecosystem since it is carcinogenic, mutagenic, and can cause damage to the respiratory, renal, hepatic, and dermatological systems. Adsorption is a sustainable alternative for the removal of Cr(VI) from the environment since it is an efficient, low-cost technique and can be adjusted according to specific environmental conditions. The use of algae biomass activated with chemical agents can be a promising solution to improve the adsorption capacity of the material and contribute to the mitigation of contamination by Cr(VI) and the protection of human health and the environment. The results of the study indicate that the activation of the red macroalgae Gelidium sp. with zinc chloride (ZnCl2) resulted in improvements in the adsorbent properties of the material for the removal of Cr(VI) in aqueous solutions. The physical characteristics of the material were analyzed, and it was observed that the surface area increased from 2.90 to 3.12 m2 g−1 after activation with ZnCl2. Furthermore, changes in the surface structure of the material were observed, with the presence of irregularities, mainly after the adsorption of Cr(VI). The analysis of functional groups indicated that the main groups present in the native biomass remained after activation with zinc, and new diffraction peaks also appeared, indicating the chemical modification of the material. The adsorption experiments were carried out under different conditions, such as pH, dosage, temperature, Cr(VI) concentration, and contact time. It was observed that the adsorption was favored under acidic conditions, with a dose of 0.05 g L−1 of activated biomass. Equilibrium was reached quickly in the first few minutes, and the general kinetic model best fitted the experimental data. The kinetic adsorption capacity was higher for the activated material (226 mg g−1) compared to the native material (114 mg g−1). Increasing the concentration of Cr(VI) in the solution resulted in an increase in the adsorption capacity, indicating that the driving force gradient was greater at higher concentrations of the contaminating ion. The isothermal data were well fitted by the Koble-Corrigan heterogeneous surface model, and the maximum adsorption capacities were estimated at 126 mg g−1 and 240 mg g−1 for native and activated biomass, respectively, at the highest Cr(VI) concentration studied (150 mg L−1). The results indicate that the activation of the red macroalgae Gelidium sp. with zinc chloride improved its adsorbent properties for the removal of Cr(VI) ions, with high adsorption capacity and efficiency, demonstrating a high potential for application in the removal of Cr(VI) metal ions in aqueous solutions. [ABSTRACT FROM AUTHOR]

In present work, the genotoxicity of Hg2+, Ag+, Cr6+, Ni2+, Pb2+, Co2+, Mn2+, Zn2+, and Cr3+ was investigated via a quantitative toxicogenomics assay, to understand the toxic mechanism of heavy metals with greater depth. Under the experimental conditions, Hg2+, Ag+, and Cr6+ showed a more serious toxic impact on the expression of functional genes (eg., oxyR, katG, grxA, osmE, emrE, dinG) than Ni2+, Pb2+, Co2+, Mn2+, Zn2+, and Cr3+, while the protein, oxidative, and membrane stress response pathways were more sensitive to the toxicity of Hg2+, Ag+, and Cr6+ than the DNA and general stress response pathways. Compared with the other kinds of heavy metals, Ni2+, Pb2+, Co2+, and Mn2+ altered the expression of functional genes (uvrY, recX, mutY, and sbmC) related to the DNA stress response pathways more seriously, while Zn2+ and Cr3+ changed the expression of the functional genes (yfjG, ydgL, ssrA, and osmC) associated with the general stress response pathway more significantly. Meanwhile, the toxicity of Ni2+, Pb2+, Co2+, and Mn2+ was slightly higher than that of Zn2+ and Cr3+ in terms of the total value of transcriptional effect level Index (TELI) by detecting the promoter activities of different functional genes. In addition, to survive the toxicity of heavy metals, the expression of multidrug efflux genes (ydgL, cyoA, emrA, and emrE) and toxicity-resistant genes (Ion, dnaJ, clpB, mutY, dnaK, rpoD, sbmC) mainly functioned. [ABSTRACT FROM AUTHOR]

Despite the excellent thermometric performance of many developed luminescent nanomaterials, their use has not gone beyond proof‐of‐concept in vivo experiments to date. An important issue that needs to be resolved before moving toward true biomedical applications of engineered nanothermometers is their potential toxicity and bioaccumulation in the human body considering the ultimate objective of clinical applications. Since most reported nanothermometers currently are not degradable materials and are mainly based on the incorporation of heavy metal ions, these aspects remain of genuine concern in the fields of nanomedicine, nanobiotechnology, nanotoxicology, and nanopharmacology. This work explores the possibility of designing visible, as well as near‐infrared, emitting luminescent ratiometric nanothermometers based on appropriate organic dye mixtures embedded in hollow disulfide‐bridged periodic mesoporous organosilica (PMO) particles. Such hybrid particles show excellent thermometric performance in the physiological temperature range (20–50 °C), favorable degradability in simulated physiological conditions, as well as no toxicity to healthy normal human dermal fibroblast (NHDF) cells in a wide concentration range. Considering the simplicity of the approach from the synthetic point of view, and the large available library of known fluorescent dyes emitting in various regions of the electromagnetic range, this motif renders a very promising approach to designing novel non‐toxic, decomposable, luminescent ratiometric thermometers. [ABSTRACT FROM AUTHOR]

Phosphorus-modified biochar has been proven to enhance the precipitation and complexation of heavy metal ions from wastewater. However, the current modification methods require large amounts of exogenous P and have high energy consumption. Hence, this study proposes and analyzes a strategy integrating biochar production, phosphorus wastewater treatment, dephosphorization waste recovery, and heavy metal removal. "BC-Ca-P" was derived from Ca-modified biochar after phosphorus wastewater treatment. The adsorption of Pb(II) by BC-Ca-P followed the Langmuir isotherm and pseudo–second–order kinetic models. The maximum adsorption capability of 361.20 mg·g−1 at pH 5.0 for 2 h was markedly greater than that of external phosphorous-modified biochar. The adsorption mechanisms were dominated by chemical precipitation and complexation. Furthermore, density functional theory calculations indicated that oxygen-containing functional groups (P-O and C-O) contributed the most to the efficient adsorption of Pb(II) onto BC-Ca-P. To explore its practical feasibility, the adsorption performance of BC-Ca-P recovered from an actual environment was evaluated. The continuous-flow adsorption behavior was investigated and well-fitted utilizing the Thomas and Yoon–Nelson models. There was a negligible P leakage risk of BC-Ca-P during heavy metal treatment. This study describes a novel and sustainable method to utilize dephosphorization waste for heavy metal removal. Article Highlights: Dephosphorization biochar waste was used to sustainably remove heavy metals from wastewater. Field-recovered dephosphorization biochar waste displayed high Pb adsorption capacity. Dephosphorization biochar for heavy metal removal is an eco–friendly waste–reduction and resource–utilization method. [ABSTRACT FROM AUTHOR]

Background: Herbal medicines used for male sexual disorders are widespread across the globe and have been noted as likely candidates for adulteration. To assure access to safe and quality herbal products, this study aimed at sampling some herbal capsules indicated for male vitality for quality analytical checks. Methods: Herbal capsules sampled from two regions were subjected to physicochemical assessment, using pharmacopeial and regulatory standards. Microbial quality analysis was also performed on the selected products. A validated HPLC method for simultaneous analysis of sildenafil citrate and tadalafil was used to detect and quantify the possible presence of phosphodiesterase inhibitors in the selected products. Results: Out of a total of 57 herbal capsules, 19 were indicated for male sexual related illnesses of which only 8 fulfilled the inclusion criteria of being used exclusively for male vitality. The majority (62.5%) of the herbal products failed the weight uniformity test but all of them disintegrated within the acceptable limit of 30 min. The moisture and heavy metal contents were within limits of acceptability. Majority (87.5%) of the herbal products failed the test for the aerobic bacteria count; however, none of the isolated bacteria was pathogenic. Sildenafil citrate was detected in the majority (87.5%) of the herbal products in concentrations of 0.98–33.95 mg/g. Two products contained both sildenafil and tadalafil. High batch-to-batch variability was recorded in some physicochemical parameters and pharmaceutical adulterants. Conclusion: High incidence of quality fails and adulteration of herbal capsules for sexual disorders observed means there is a real risk of unintended dosing with phosphodiesterase inhibitors. This represents a public health issue and necessitates tighter monitoring of production standards by the regulator. [ABSTRACT FROM AUTHOR]

Pyrolysis of animal manure at high temperature is necessary to effectively immobilize heavy metals, while the available phosphorus (P) level in biochar is relatively low, rendering it unsuitable for use as fertilizer. In this study, the pretreatment of swine manure with different potassium (K) sources (KOH, K2CO3, CH3COOK and C6H5K3O7) was conducted to produce a biochar with enhanced P availability and heavy metals immobility. The addition of all K compounds lowered the peak temperature of decomposition of cellulose in swine manure. The percentage of ammonium citrate and formic acid extractable P in biochar increased with K addition compared to undoped biochar, with CH3COOK and C6H5K3O7 showing greater effectiveness than KOH and K2CO3, however, water- extractable P did not exhibit significant changes. Additionally, the available and dissolved Si increased due to the doping of K, with KOH and K2CO3 having a stronger effect than CH3COOK and C6H5K3O7. X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) analysis revealed that K addition led to the formation of soluble CaKPO4 and silicate. In addition, the incorporation of K promoted the transformation of labile copper (Cu) and znic (Zn) into the stable fraction while simultaneously reducing their environmental risk. Our study suggest that the co-pyrolysis of swine manure and organic K represents an effective and valuable method for producing biochar with optimized P availability and heavy metals immobility. [ABSTRACT FROM AUTHOR]

Among the steelmaking slag, secondary metallurgy slag (SMS) is the most problematic to be recycled. Several attempts to recover such slag as lime replacement, slag flux, pozzolanic materials have been made for long time with pros and cons. However, the amount of recyclable slag is limited and often their employment requires higher energy demand than traditional materials. Nevertheless, the use of SMS in agriculture is poorly or never considered. In this article, the legal and technical evaluation of SMS as raw material for fertilizers production is investigated. Compliance of technical specification, toxic metals concentration, and leaching behavior allows to confirm the technical feasibility of SMS use as a raw material for fertilizers manufacture. Both from the literature data and the experimental results on 16 industrial SMS samples, the requirements for calcium‐magnesium‐sulfur‐based fertilizers, soil correctives and for sanitizing agricultural sewage sludge, appear fully satisfied. The CaO concentration in SMS (35–60 wt%) is abundantly higher than the requirements (≥15 wt%) and CaO is present in most part as water‐soluble complexes such as calcium aluminates (70 wt%), silicates (10 wt%), and sulfide (4 wt%). The pH of the SMS samples leachate is comparable to that of fresh lime (12.35 vs 12.46), highlighting a better behavior for sewage sludge sanitation with respect to limestone (9.98). The measured toxic metals and leachate elements concentration over the corresponding admittable threshold are always lower than 0.5 and 1.0 (mg kg−1/mg kg−1) for liming materials. Finally, these results lead to officially approve the use of SMS as soil corrective according to the Italian Fertilizer Regulation. [ABSTRACT FROM AUTHOR]

Summary Metal contamination in rice grains is a critical global issue, posing serious health risks and affecting food safety, especially in countries like Malaysia where rice is a staple food. This study aimed to assess the effectiveness of various cooking treatments, with a focus on parboiling before absorption cooking (PBA), in reducing metal contamination in Malaysian rice. Metal levels were measured using tandem inductively coupled plasma mass spectrometry (ICP‐MS/MS), and health risks were assessed following USEPA guidelines. Parboiling before absorption cooking was found to eliminate 77.9% of toxic metals and 68.4% of essential metals while keeping arsenic (As), cadmium (Cd) and lead (Pb) concentrations below permissible limits. Deterministic health risk assessment indicated that PBA reduced hazard index by 84.5% and lifetime carcinogenic risk (LCR) from As exposure by 88.9%. Hazard quotient for nickel (Ni) and zinc (Zn) remained acceptable for all age groups except for As in children, where LCR exceeded permissible limits. Monte Carlo simulations revealed that over 95% of individuals across age groups faced unacceptable non‐carcinogenic and carcinogenic risks from As exposure, regardless of cooking method. In conclusion, PBA effectively lowered metal concentrations and health risks, especially for toxic metals in rice. Future studies could enhance risk assessment accuracy by analysing metal bioavailability and speciation of metals particularly As. [ABSTRACT FROM AUTHOR]

Summary The use of black soldier fly larvae (BSFL) to valorise different organic waste streams and the subsequent use of resulting larvae as a feedstock ingredient is increasing rapidly in several regions across the globe. The lack of knowledge about several safety issues including chemical contaminants (e.g. heavy metals) seems to affect the upscaling and commercialisation of this product. This study evaluates the safety of the BSFL against chemical contaminants including heavy metals and mycotoxins in both BSFL and frass samples reared with different food waste streams (e.g. soy waste, customised bread‐vegetable diet, food waste mixture, supermarket and childcare centre) from two commercial production facilities. The effect of larval instars and post‐harvest treatments (e.g. blanching and drying) on the safety of the BSFL was also investigated. The concentration of heavy metals was primarily influenced by the concentration in the food waste streams. The concentration was also higher in 6th instar compared to 5th instar larvae. The effect of blanching and drying have a varied effect on the concentration of heavy metals. Mycotoxins were found to be below the limit of quantification for all samples. The outcomes of this study indicated that BSFL grown on food waste streams and the resulting frass is safe against different heavy metals analysed. The findings of this study will assist the commercial BSFL manufacturers with the identification of relevant control points to ensure the chemical safety of their products. Therefore, encourage the use of different food waste streams as feedstock for rearing BSFL. [ABSTRACT FROM AUTHOR]

Introduction: The drilling industry is one of the main sectors of the oil industry, and oil drilling is one of the most specialized industrial activities. Large-scale production of sugarcane bagasse in Khuzestan Province creates an environmental opportunity to utilize this agricultural byproduct in different sections as a valuable byproduct. This study aimed to investigate the ability of the raw form of bagasse and its transformed structure in heavy metal fixation in drilling mud and to investigate the efficiency of crude bagasse, processed bagasse, and biochar adsorbents in removing heavy metals from the drilling mud residues of Ahvaz oil field. Methods: Sampling of drilling mud waste from Mishan Geological Formation (MGF) and Aghajari Geological Formation (AGF) was done on a vibrating sieve. The treatments examined in this research include the contact time in six levels (30, 60, 90, 120, 150, and 180 min), amount of the adsorbent in three levels (0.1, 0.5, and 1 g), adsorbent type in three levels (crude bagasse, processed bagasse, and biochar), and the formation type in two levels (Aghajari and Mishan). After chemical digestion, the samples were placed in contact with crude bagasse, processed bagasse, and biochar according to the designed conditions. Then, the removal percentages of Ba, Ni, V, Cd, Fe, and Pb were calculated. Means were compared using Duncan's test at the 1% level. Results and Discussion: The results showed that the biochar adsorbent is the most efficient compared to other adsorbents. The maximum removal percentages of heavy metals Ba, Ni, V, Cd, Fe, and Pb by crude bagasse are 72.53%, 68.89%, 79.49%, 76.88%, 49.42%, and 85%, respectively. In addition, the results showed that the maximum removal percentages of heavy metals Ba, Ni, V, Cd, Fe, and Pb by crude bagasse are 81/72%, 83/89%, 86/67%, 83/44%, 64/41%, and 90.72%, respectively. The maximum efficiency of biochar for adsorbing heavy metals Ba, Ni, V, Cd, Fe, and Pb is 90.70%, 91.84%, 88.89%, 88.75%, 78.59%, and 97.75%, respectively. The maximum amount of heavy metals adsorbed by all adsorbents was 1 gr/L, and the adsorption efficiency increased by increasing the amount of the adsorbent from 0.2 to 1 gr/L. In examining the effect of contact time, the maximum removal percentage of heavy metals barium and cadmium was obtained in 120 min, nickel and lead in 90 min, and vanadium and iron in 60 min. After the above contact times, there was no increase in the maximum percentage of metal removal. [ABSTRACT FROM AUTHOR]

Lead (Pb(II)) ions in water pose a significant threat to both human health and aquatic ecosystems. Various approaches have been employed for wastewater treatment, but adsorption is often preferred due to its effectiveness. However, its practical application is limited by the large quantities of adsorbent required, which consequently increases operational costs. In this study, orange-modified iron-oxide nanoparticles (O-Fe3O4) are synthesized from agro-waste mass (orange peel), and adsorption experiments were conducted for the removal of Pb(II) from aqueous solution. Characterization studies confirm that O-Fe3O4 nanoparticles possess a mesoporous hexagonal nanocrystalline structure, with diameters measuring less than 100 nm. The adsorption process was optimized using a central composite design framework combined with response surface methodology. The analysis of interaction effects demonstrated that they significantly influenced the effectiveness of adsorption removal. The study revealed that an initial concentration of 25 mg/L, a dosage of 0.2 g/L, a contact period of 90 min, and a pH of 5.5 were the optimum conditions to achieve above 95% of Pb(II) removal. The green synthesized O-Fe3O4 nanoparticles, which presented high efficacy, makes it a promising option for implementing the sustainable water purification. [ABSTRACT FROM AUTHOR]

The giant panda (Ailuropoda melanoleuca) is recognized worldwide as an icon for wildlife conservation. The Qinling subspecies (Ailuropoda melanoleuca qinlingensis) inhabiting the Qinling Mountains is more endangered. Previous studies have indicated that Qinling pandas are potentially at risk from environmental pollutants, which they are exposed to via food and drinking water. However, there is little information about the surface water quality in the Qinling Mountains, and it is unknown whether drinking water is an important pollutant source for pandas. Water samples were collected from five different nature reserves in Qinling, each of which is home to a population of pandas. The samples were analyzed for five essential metals of copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), and nickel (Ni) and four non-essential metals of lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg). The concentrations of all heavy metals (HMs) were higher in buffer zones than in the core areas and were highest in Foping and Niuweihe nature reserves. The concentrations of mercury exceeded the water quality standard in the core zone of three reserves, suggesting that NWH (Niuweihe), THS (Tianhuashan), and PHL (Pingheliang) giant panda populations were at risk from mercury toxicity. The accumulation of other elements over time could also pose a serious risk to pandas. Three main sources of pollution were identified: coal combustion, waste incineration, and fertilizer use; traffic-related activities; and metal mining. Environmental pollution is compromising the efforts to conserve the giant panda, and measures need to be put in place to control pollution sources. [ABSTRACT FROM AUTHOR]

In order to understand the impact of lead-zinc mining and processing activities on the soil ecological environment of downstream agricultural land, taking the downstream agricultural land of a lead-zinc mining enterprise in Guizhou as the research object, and the soil and agricultural products samples in A and B areas of the study area were collected by random distribution method, and the contents of eight heavy metals were determined. The pollution characteristics and risk assessment of eight heavy metals (Pb, Cd, Ni, As, Hg, Cu, Cr, Zn) in the soil of agricultural land in the study area were analyzed by single factor pollution index (Pi) method and Nemero comprehensive pollution index (PN ). High risk quotient (HQ) and high risk index (HI) were used to evaluate the health risks of heavy metals in rice and corn to adults and children. The results showed that the soil of agricultural land in this area was polluted by different degrees of heavy metals, Cd was heavily polluted, As and Zn were slightly polluted. The comprehensive pollution index of soil heavy metals in area A was greater than that in area B, and Cd contributed the most to the comprehensive pollution index. The heavy metals in agricultural products in this area were mainly Cd content exceeding the standard, and the Cd exceeding rate of rice was greater than that of corn;there was no significant correlation between the total amount of heavy metals in rice and corn and the total amount of heavy metals in soil in the study area. Intake of rice and corn in this area, single heavy metals Cd and As had a great risk to human health. Rice had a great possibility of health impact on the human body, and the impact on children was significantly greater than that on adults. Corn did not have a health impact on the human body. [ABSTRACT FROM AUTHOR]

Global concern about the accumulation of heavy metal(loid)s (HMs) in agricultural soils and its subsequent effects on human health has increased. In particular, arsenic is a metalloid with known toxic and carcinogenic properties. This study was conducted with the aim of investigating arsenic contamination in agricultural soils of Hashtroud County, while assessing the levels of some heavy metals and the associated ecological and health risks due to possible exposure to these contaminants. The average concentrations of zinc (Zn), lead (Pb), nickel (Ni), copper (Cu), chromium (Cr), arsenic (As), cobalt (Co), and cadmium (Cd) (respectively, 72, 42, 41, 40, 24, 16, 13, and 0.6 (mg/kg)) did not exceed the national guideline value except for As. Arsenic was the element most enriched in the study area (enrichment factor (EF): 3.3). In general, the soil samples showed moderate ecological risk (RI = 174.17). The non-carcinogenic risks of HMs were acceptable, while the carcinogenic risk value (LCR) for As exceeded the threshold of 1 × 10−4 at 10% of the samples. Source attribution of HMs using the positive matrix factorization (PMF) model showed that Zn and Pb were mainly due to vehicle emissions. Agricultural activities and atmospheric deposition were the predominant sources of Cu and Zn; As and Cd were from natural sources; and Ni, Cr, and Co were from mixed sources of pedogenic factors and agricultural activities. To conclude, in study area, addressing arsenic as a main concern is crucial due to its ecological and health risks. The agro-geogenic source with a contribution rate of 64.87%, was identified as the primary origin of the elements. Further research is needed to investigate the bioaccumulation and bioavailability of HMs in the soil-crop system. [ABSTRACT FROM AUTHOR]

Paper-based microfluidics combined with potentiometric measurement has emerged as an attractive approach for detecting various chemical ionic moieties. Detection of heavy metal ions, using paper substrates as solution sampling and delivery systems remains challenging despite efforts to introduce several physico-chemical paper substrate modifications to stop adsorption of ions onto the paper substrates. This study quantitatively investigates the adsorption of heavy metal ions on the paper substrates during paper-based potentiometric measurements and explains the super-Nernstian response of potentiometric sensors through local depletion of heavy metal ions from the solution. Consequently, based on the investigated ion adsorption, a corrective potential protocol was established for the electrodes coupled with paper-based solution sampling by predicting interference free sensor response from paper-based measurement. Furthermore, the ion adsorption was also recorded for mixed metal ion solutions to understand competitive primary/interfering ions adsorption onto the paper substrates and establish corrective measures to predict interference free sensor response. In this method, no modifications of the paper substrates are necessary before actual potentiometric measurements. The proposed corrective protocol allows prediction of sensor response based on the paper-based solution sampling potentiometric measurement, providing a simple methodological approach based on correction of potential readout of the potentiometric sensor, thus completely resigning from the need of modifying paper substrate for measurements of heavy metal ions. [ABSTRACT FROM AUTHOR]

Singlet oxygen production and its reactivity have significant implications in fields ranging from polymer science to photodynamic therapy. Extensive research has focused on the development of organic-based materials and heavy metal complexes, including Ru(II), Rh(III), Ir(III) and Pt(II). However, metal complexes containing Au(I) have been scarcely explored and warrant further investigation. This review provides a comprehensive analysis of reported compounds, classified based on the ligands coordinated to the gold(I) centre. Additionally, future directions in photosensitizer development and singlet oxygen applications are discussed. [ABSTRACT FROM AUTHOR]

AbstractIn China, increasing breeding waste has caused environmental problems. This study explored the possibility of using breeding waste compost (BWC) instead of chemical fertilizer in vegetable cultivation. The experiment included no fertilizer (CK), 100% chemical fertilizer (CF), 10, 20, and 30% substitution of cow dung compost (CDC), goose dung compost (GDC), and duck dung compost (DDC) with chemical fertilizer (C01, C02, C03, G01, G02, G03, D01, D02, D03). The results showed that BWC, particularly GDC, promoted lettuce growth and development. Compared to CK, the leaf fresh and dry weight of G03 were the highest, increasing significantly by 6.60 and 7.29 times, and the root fresh and dry weight of G02 were the highest, increasing significantly by 12.72 and 6.00 times. Different BWC improved soluble sugar, soluble protein, and Vitamin C to varying degrees, and the nitrate contents of some BWC treatments were lower than that of CK and CF. Conversely, CF had the highest nitrate accumulation and limited effects on certain growth and quality parameters. The mineral elements in lettuce were also affected by the type and dosage of fertilizers. The total nitrogen of CF, total phosphorus of G03, total potassium of G02, Ca and Mg of D01, Fe of CF, and Zn of G02 were at the peak. The rapid increase of biomass in GDC treatments led to reductions in Ca and Fe. Applying fertilizers would affect heavy metals in lettuce to unequal degrees, but all were within the food safety scope. The principal component analysis revealed the comprehensive effect of GDC treatments was recommended. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are structures with high surface area that can be used to remove heavy metals (HMs) efficiently from the environment. The effect of MOFs on HMs removal from contaminated soils has not been already investigated. Monometallic MOFs are easier to synthesize with high efficiency, and it is also important to compare their structures. In the present study, Zn-BTC, Cu-BTC, and Fe-BTC as three metal-trimesic acid MOFs were synthesized from the combination of zinc (Zn), copper (Cu), and iron (Fe) nitrates with benzene-1,3,5-tricarboxylic acid (H3BTC) by solvothermal method. BET analysis showed that the specific surface areas of the Zn-BTC, Cu-BTC, and Fe-BTC were 502.63, 768.39 and 92.4 m2g-1, respectively. The synthesized MOFs were added at the rates of 0.5 and 1% by weight to the soils contaminated with 100 mgkg-1 of Zn, nickel (Ni), lead (Pb), and cadmium (Cd). Then quinoa seeds were sown in the treated soils. According to the results, the uptakes of all four HMs by quinoa were the lowest in the Cu-BTC 1% treated pots and the lowest uptakes were observed for Pb in shoot and root (4.87 and 0.39, μgpot-1, respectively). The lowest concentration of metal extracted with EDTA in the post-harvest soils was for Pb (11.86 mgkg-1) in the Cu-BTC 1% treatment. The lowest metal pollution indices were observed after the application of Cu-BTC 1%, which were 20.29 and 11.53 for shoot and root, respectively. With equal molar ratios, highly porous and honeycomb-shaped structure, the most crystallized and the smallest constituent particle size (34.64 nm) were obtained only from the combination of Cu ions with H3BTC. The lowest porosity, crystallinity, and a semi-gel like feature was found for the Fe-BTC. The synthesized Cu-BTC showed the highest capacity of stabilizing HMs, especially Pb in the soil compared to the Zn-BTC and the Fe-BTC. The highly porous characteristic of the Cu-BTC can make the application of this MOF as a suitable environmental solution for the remediation of high Pb-contaminated soils. [ABSTRACT FROM AUTHOR]

This study analyses surficial sediments for heavy metal contamination in three different zones: Western India, Ganga Plains, and Central India. To estimate the geochemical environment of the surficial soil, five heavy metals, namely Co, Cu, Ni, Zn, and Pb were examined. Enrichment factor (EF) indicated the highest contamination for Co which showed deficient to minimal contamination in 11 samples, moderate contamination in 11 samples, significant contamination in 16 samples and very significant contamination in 1 amongst the 39 samples from various locations in all three zones depicted. The geo-accumulation index suggests that the variability in Co observed was −1.5 to 2.68 indicating augmentation of the Co concentrations in the study areas with respect to background values. Among 39 of the total locations sampled, 20 of them fall in the category of no pollution with respect to Pollution Load Index (PLI), while 18 fall under the category of moderate pollution and one location falls under the category of heavy pollution. Although all the indices suggested that the zones have not been subjected to extreme levels of pollution yet, appropriate measures may be taken to contain further anthropogenic contamination of these soils to preserve the surficial soils and their ecology. [ABSTRACT FROM AUTHOR]

In response to the ever increasing need to develop more efficient and sustainable methods for removing heavy metal contaminants from aqueous systems, the following article reports on the design of highly mesoporous alginate‐derived materials (Starbon®) and their application to the adsorption of heavy metals. Using the Starbon® process to expand, dry and pyrolyse an inherently porous polysaccharide precursor, it was possible to produce mesoporous materials (BJH mesopore volumes 0.81–0.94 cm3 g−1) with large surface areas (157–297 m2 g−1) across a range of low pyrolysis temperatures (200–300 °C). The mechanisms of thermal decomposition were explored in terms of chemical and structural changes using N2‐sorption porosimetry, thermogravimetric analysis, titration, FT‐IR spectroscopy and 13C NMR spectroscopy. It was found that, as a result of intermolecular dehydration and crosslinking, sufficient chemical stability is obtained by the intermediate temperature of 250 °C, with limited improvement seen at higher temperatures. In addition, the materials retained large metal adsorption capacities (0.70–1.72 mmol g−1) as well as strong selectivity for Cu2+ ions (over Co2+ and Ni2+), as compared to commercial petrochemical‐derived cation exchange resin Amberlite™ Mac 3H. Thus, highlighting the potential of Starbon® materials as a sustainable answer to the widespread problem of heavy metal‐contaminated wastewaters. [ABSTRACT FROM AUTHOR]

Bacterial exopolysaccharides (EPS) have emerged as one of the key players in the field of heavy metal-contaminated environmental bioremediation. This study aimed to characterize and evaluate the metal biosorption potential of EPS produced by a novel Psychrobacillus strain, NEAU-3TGS, isolated from an iron ore deposit at Tamra iron mine, northern Tunisia. Genomic and pan-genomic analysis of NEAU-3TGS bacterium with nine validated published Psychrobacillus species was also performed. The results showed that the NEAU-3TGS genome (4.48 Mb) had a mean GC content of 36%, 4,243 coding sequences and 14 RNA genes. Phylogenomic analysis and calculation of nucleotide identity (ANI) values (less than 95% for new species with all strains) confirmed that NEAU-3TGS represents a potential new species. Pangenomic analysis revealed that Psychrobacillus genomic diversity represents an "open" pangenome model with 33,091 homologous genes, including 65 core, 3,738 shell, and 29,288 cloud genes. Structural EPS characterization by attenuated total reflectance-Fourier transform infrared (ATRFTIR) spectroscopy showed uronic acid and α-1,4-glycosidic bonds as dominant components of the EPS. X-ray diffraction (XRD) analysis revealed the presence of chitin, chitosan, and calcite CaCO3 and confirmed the amorphous nature of the EPS. Heavy metal bioabsorption assessment showed that iron and lead were more adsorbed than copper and cadmium. Notably, the optimum activity was observed at 37°C, pH=7 and after 3 h contact of EPS with each metal. Genomic insights on iron acquisition and metabolism in Psychrobacillus sp. NEAU-3TGS suggested that no genes involved in siderophore biosynthesis were found, and only the gene cluster FeuABCD and trilactone hydrolase genes involved in the uptake of siderophores, iron transporter and exporter are present. Molecular modelling and docking of FeuA (protein peptidoglycan siderophore-binding protein) and siderophores ferrienterobactine [Fe+3 (ENT)]-3 and ferribacillibactine [Fe+3 (BB)]-3 ligand revealed that [Fe+3 (ENT)]-3 binds to Phe122, Lys127, Ile100, Gln314, Arg215, Arg217, and Gln252. Almost the same for [Fe+3 (ENT)]-3knowledge, this is the first report on the characterization of EPS and the adsorption of heavy metals by Psychrobacillus species. The heavy metal removal capabilities may be advantageous for using these organisms in metal remediation. [ABSTRACT FROM AUTHOR]

Sustainable structures are an important area of research, particularly for anticipated extended human presence on the Moon or Mars. Persistent human presence on the Moon will require building materials that are already present at the site to construct bases. The high cost associated with reinforcing metal (rebar) in mission payloads necessitates the exploration of alternative reinforcement methods for sustained lunar bases. Human hair is strong in tensile strength and will become available in any long-term mission. By using otherwise wasted hair instead of heavy metal, mission payloads and costs could be lowered. Concrete workability, compressive strength, and porosity were measured for a series of different cement compositions. These compositions consisted of combinations of Ordinary Portland Cement (OPC), lunar regolith, deionized (DI) water and human hair. Increased workability and porosity were found for increasing hair concentrations. Compressive strength slightly decreased with increased hair concentration. [ABSTRACT FROM AUTHOR]

Heavy metal contamination and potential risks to human health related to consuming major food crops near Iringa Municipal dumpsite are presented. Soil samples, maize (Zea mays L.) and common beans (Phaseolus vulgaris L.) were collected downslope around the dumpsite during wet season. Soil samples were analyzed using Energy-Dispersive X-Ray Fluorescence (EDXRF) while crop (maize and beans) samples were analyzed using Flame Atomic Absorption Spectrophotometer (FAAS). The potential health risks associated with human exposure to heavy metals in maize and common beans was evaluated according to the method prescribed by the United States Environmental Protection Agency. The concentrations Cd (3.25–10.78 mg/kg), As (1.84–10.98 mg/kg) and Ni (71.74–55.10 mg/kg) in soil samples exceed the maximum allowable limits set by Tanzania Bureau of Standards (TBS). The average heavy metal concentration in food crops followed the trend Cd, As < Cr, Pb < Ni < Cu < Mn < Zn with Pb in maize (0.96 mg/kg) and common beans (0.81 mg/kg) above FAO/WHO regulatory standards of 0.3 mg/kg. This implied health concerns to consuming food crops grown in the vicinity of the dumpsite. Further, lifetime–incremental cancer risk (ILCR) assessment suggest that consuming maize and common beans from the study area could increase the risk of both cancer and non-cancerous diseases in both adults and children. However, the degree of ILCR in children was noticeably higher (1.0 × 10–2) than in adults (5.10. × 10–6) for Pb in common beans. Therefore sustainable waste management should be stressed and continuous monitoring of environments around dumpsites is crucial to mitigate the negative impacts on public and environments. [ABSTRACT FROM AUTHOR]