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Macroalgae are widely used for bioindication and assessment; however, in the case of pollutants of different origin, it is still unclear which contaminants in thalli can be regarded as indicative because too many factors influence the ability of algae to uptake them. The present study is a part of an international HAZLESS project and was conducted in the eastern Gulf of Finland (GoF). The main goal of our study was the application of metal concentrations in macroalgae as a tool for environmental quality assessment. To achieve this goal, we calculated the threshold metal concentrations in macroalgae (Cladophora glomerata) and compared our obtained values with actual concentrations. We found significant Spearman correlations in May between metals in sediments and pore water (−0.73 for Zn, −0.62 for Cd, 0.85 for Pb) and also between metals in algae and metals in pore water (1 for Cu and Cd, 0.98 for Zn and Pb). In July, Pb in algae were significantly correlated with Pb in pore water (0.88). The application of the calculated environmental quality standard (EQSMPC) for macroalgae has shown moderate pollution by Cu and Pb in the coastal zone of the eastern GoF. This was confirmed by an assessment based on the comparisons of metal concentrations in water with Environmental Quality Standards for water (EQSw). However, differences in the bioaccumulation factor and EQSMPC between May and July have shown that it is necessary to compare samples taken during the same period every year for adequate results in long-term monitoring. Considering the sensitivity of accumulating processes to the surrounding environment, we believe that in the case of habitats with diverse conditions, even for the same species of algae, threshold values should be calculated and used individually for every habitat. Our results have shown that this approach can be widely used for an assessment of environmental quality via metal concentrations in opportunistic macroalgae and can be recommended for further use. [ABSTRACT FROM AUTHOR]

Novel photoluminescent carbon dots (CDs) were synthesized through a facile hydrothermal method using Hibiscus tea extract as a natural carbon source and boric acid as a boron source. The optical and physicochemical properties of the as-synthesized nitrogen- and boron-doped CDs (NB-CDs) were characterized using UV–Visible (UV–Vis), photoluminescence (PL) spectroscopy, Fourier-transform infrared (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The as-synthesized NB-CDs showed spherical morphology of approximately 6.2 ± 0.5 nm with quantum yield (9.2%), high aqueous solubility, strong photo-stability, and excitation-dependent PL behavior. The obtained NB-CDs exhibited high stability over a wide pH range and high ionic strength. Additionally, NB-CDs exhibited PL enhancement response with excellent sensitivity toward multi-metal ions, including Ag+, Cd2+, and Cr3+ ions, with very low detection limits of 44.5, 164.4, and 54.6 nM, respectively, with a wide concentration range of 0–10 μM. Upon testing the cytotoxicity of the NB-CDs at a concentration of 20 μg/mL for 24 h, we found no obvious inhibition of cell viability. Therefore, the proposed sensor method can be successfully applied to detect Ag+, Cd2+, and Cr3+ ions in cell imaging as well as in real water environmental samples. [ABSTRACT FROM AUTHOR]

A late-deposited colloform banded sphalerite from Pcheloyad and Sporno deposits in samples from the Earth and Man National Museum was studied. Its composition is very close to the theoretical one for sphalerite. Iron, gallium, cadmium and indium are established as trace elements in concentrations lower than those in earlier deposited sphalerite generations. The presence of wurtzite was proved by X-ray powder diffraction. A similar low-temperature colloform banded sphalerite of the Schalenblende type has so far not been described in the lead-zinc Zvezdel-Pcheloyad ore field. [ABSTRACT FROM AUTHOR]

The present study provides geochemical and geochronological data about Posušje bauxites in Bosnia and Herzegovina with the aim to characterize them as Critical Raw Materials (CRMs) sources and to put constraints on the time and genesis of the deposit. Boehmite is the bauxites' main Al-bearing mineral, while gibbsite is a minor constituent. Hematite is the dominant Fe-phase, whereas goethite is rare. The chemical analyses indicate that the Al2O3 content ranges from 49.6 to 63.0 wt %, Fe2O3 varies from 16.5 to 33.7 wt % and the SiO2 content is usually <0.5 wt %. TiO2 content ranges between 2.6 and 3.2 wt %. Typical trace elements are V (353-787 ppm), Cr (498-1055 ppm), Zr (382-558 ppm), Sc (42-72 ppm), and Ga (40-47 ppm). The sum of REEs is 357-1112 ppm. The U-Pb zircon dating indicates an age of Posušje bauxite formation at 56.6±0.5 Ma. This age closely aligns with the global climatic event that occurred approximately 56 Ma ago, called Paleocene--Eocene Thermal Maximum (PETM). [ABSTRACT FROM AUTHOR]

Regarding the aspect of mineral, thermo-mineral, and thermal waters, on the territory of the Republic of North Macedonia, there are 65 registered locations, of which 8 are categorized as spas. This includes the Kežovica spa, also known as the Štipska spa. In the vicinity of Kežovica Spa is the thermo-mineral L'Dži spring with mineralization around 1.3 g/L and the water temperature at the time of sampling was 50.1 °C. Spring L'Dži is generated by a fault structure and is linked to a granite massif of Mesozoic age. These are alkaline waters (pH = 8.3) and the hydrochemical type is chloride-sodium. Regarding the trace elements, the water of the L'Dži spring contains a large amount of boron and silica. Water also contains an increased content of arsenic (200 µg/L) and tungsten (169 µg/L). Elevated concentrations of As and W are characteristic of alkaline thermal waters in reducing conditions. Often elevated concentrations of Mo are accompanied by elevated concentrations of As and W, which is also the case. [ABSTRACT FROM AUTHOR]

The concentrations of Fe, Mn, Co, Cd, Zn, Cu, Mo, and As were registered in broad intervals and are elevated compared to the mean values for the ocean water. Vertical distributions of the element concentrations in the pore waters along four sediment cores show distinct differences, mainly for the elements Fe, Mn, Cu, and Zn. Bioturbation activities developed in the depth interval 7-15 cm could be a probable reason for the variation trends. The distributions for the elements As, Cd, Co and Zn are conservative type and the patterns for the Mo and Ni -- scavenged type. The obtained pore water profiles are similar to the distribution trends for areas in the Eastern Equatorial Pacific and show different patterns from the pore waters from the Western Pacific. [ABSTRACT FROM AUTHOR]

A laboratory experiment was performed to find out the potential bioaccumulation of metals (Al, Cu, Cd, Ni, Pb, Fe, Mn) in aquatic plants acting as natural biosorbents in the environment depending on the variation of water pH. Two plants were selected for the study: branched bur-reed—Sparganium erectum L., as a representative of emergent plants; and river water-crowfoot—Ranunculus fluitans Wimm., 1841, as a representative of submergent plants. The bioaccumulation of metals in plants relative to water (BCFW) was determined, and the metal pollution index (MPI) was calculated. The metal content in water and plants before the experiment was arranged in the following series of increasing values: Cd = Ni < Cu < Pb < Mn < Al < Fe (water) and Cd < Cu < Ni < Pb < Al < Fe < Mn (in both plants). The lowest concentration of cadmium was found in water both at the end and beginning of the experiment. In turn, aluminum level increased, and its concentration was the highest in both acidic and alkaline water. This suggests that aluminum is definitely more available to the organisms living in it under such conditions, and in higher concentrations may be a limiting factor for them. Bioaccumulation of metals (BCFW) in neutral and alkaline environments was higher in branched bur-reed, and in acidic conditions in river water-crowfoot. This may provide a basis for using specific plant species to selectively accumulate metals depending on the range of water pH. This is also supported by the MPI values, which indicate that they have a very high and often the highest impact on metal pollution levels. The observed variability of metals bioaccumulation against the condition of hydromacrophytes makes it possible to consider these plants as biosorbents used in constructed biological treatment plants, which, depending on the species placed there, can selectively absorb particular trace elements. The plants used in the experiment are common hydromacrophytes of Europe, so they can be used in the construction of artificial wetlands across the continent. The apparent diversity of metal accumulation in relation to hydromacrophytes indicates that this type of site can be inhabited by specific species, which can significantly improve the purification of natural or anthropogenic water reservoirs, i.e., those that are intended to perform a filtering function. [ABSTRACT FROM AUTHOR]

Many environmental monitoring works have been carried out using biomarkers as a tool to identify the effects of oil contamination on marine organisms; however, only a few studies have used sea urchin gonadal tissue for this purpose. Within this context, the present work aimed to understand the impact of an oil spill, proposing the use of sea urchin gonadal tissue as a biomarker for environmental contamination by trace metals in the species Paracentrotus lividus. Biometric analysis, quantification analyses of the elements Cd, Pb, Ni, Fe, Mn, Zn, and Cu, as well as histopathological evaluations were performed in gonads of P. lividus collected from an area affected by hydrocarbons, named as impacted shore (IS) and an area not affected, named reference shore (RS). The results showed that carapace diameter (DC), total wet weight (WW), and Cd concentrations in the gonads were significantly influenced by the interaction between the rocky shores of origin, the months of sampling, and by the sex of the individuals. Moreover, from July until September, the levels of Zn and Cd were significantly lower in male than in female gonads. In July (the month of the oil spill), the indexes of histopathological alterations (IHPA) of membrane dilation were significantly higher in individuals from the IS, compared to the individuals from the RS. In addition, there were significant correlations between biometric variables (wet weight, diameter of carapace, gonadal weight, and gonadosomatic index) and the elements Cd, Cu, Ni, and Mn concentrations. Lastly, a delay in the gametogenic cycle of the sea urchins from IS was also observed. Taken together, these findings suggest that direct exposure to trace metals induces histopathological lesions in P. lividus' gonads and affects its reproductive cycle. [ABSTRACT FROM AUTHOR]

Dolphinfish (Coryphaena hippurus) is a popular seafood choice worldwide, however, except for mercury (Hg) and selenium (Se), little is known about the concentration of other trace elements in dolphinfish muscle tissue, especially in the northwest Atlantic Ocean. This study investigated the relationship between body length (61 to 94 cm fork length) and trace element [silver (Ag), arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), Hg, manganese (Mn), nickel (Ni), lead (Pb), Se, and zinc (Zn)] concentrations in muscle tissue of dolphinfish caught off Long Island, New York (n = 16). There was a positive relationship with body length for As and Hg, a negative relationship with body length for Cu and Zn, and no relationship with body length for Cd, Fe, Mn, Pb, and Se. A negative relationship between the Se:Hg molar ratio and body length and Se:Hg molar ratio and Hg concentration was observed. Dolphinfish were low in Hg with only 18.9% (n = 3) of individuals exceeding the U.S. EPA human health criterion of 0.3 µg/g wet weight, making this species a suitable seafood choice to reduce dietary intake of Hg at the investigated body length. All fish had a Se:Hg molar ratio > 1:1 indicating that Se may have a protective effect against Hg toxicity. The selenium health benefit value (HBVSe) for all individuals was > 1, indicating there may be health benefits from consuming dolphinfish. [ABSTRACT FROM AUTHOR]

The suitability of lake sediment cores to reconstruct past inputs, regional pollution, and usage patterns of pesticides has been shown previously. Until now, no such data exist for lakes in eastern Germany. Therefore, 10 sediment cores (length 1 m) of 10 lakes in eastern Germany, the territory of the former German Democratic Republic (GDR), were collected and cut into 5–10-mm layers. In each layer, concentrations of trace elements (TEs) As, Cd, Cr, Cu, Ni, Pb, S, and Zn, as well as of organochlorine pesticides (OCPs), i.e., dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH), were analyzed. A miniaturized solid–liquid extraction technique in conjunction with headspace solid-phase microextraction (HS-SPME) and gas chromatography–mass spectrometry (GC–MS) was used for the latter. The progression of TE concentrations over time is uniform. It follows a trans-regional pattern and is indicative of activity and policy making in West Germany before 1990 instead of those in the GDR. Of OCPs, only transformation products of DDT were found. Congener ratios indicate a mainly aerial input. In the lakes' profiles, several regional features and responses to national policies and measures are visible. Dichlorodiphenyldichloroethane (DDD) concentrations reflect the history of DDT use in the GDR. Lake sediments proved to be suitable to archive short- and long-range impacts of anthropogenic activity. Our data can be used to complement and validate other forms of environmental pollution long-term monitoring and to check for the efficiency of pollution countermeasures in the past. [ABSTRACT FROM AUTHOR]

The goal of the present study is to assess the soil quality in Bulgaria using (i) an appropriate set of soil quality indicators, namely primary nutrients (C, N, P), acidity (pH), physical clay content and potentially toxic elements (PTEs: Cu, Zn, Cd, Pb, Ni, Cr, As, Hg) and (ii) respective data mining and modeling using chemometrical and geostatistical methods. It has been shown that five latent factors are responsible for the explanation of nearly 70% of the total variance of the data set available (principal components analysis) and each factor is identified in terms of its contribution to the formation of the overall soil quality—the mountain soil factor, the geogenic factor, the ore deposit factor, the low nutrition factor, and the mercury-specific factor. The obtained soil quality patterns were additionally confirmed via hierarchical cluster analysis. The spatial distribution of the patterns throughout the whole Bulgarian territory was visualized via the mapping of the factor scores for all identified latent factors. The mapping of identified soil quality patterns was used to outline regions where additional measures for the monitoring of the phytoavailability of PTEs were required. The suggested regions are located near to thermoelectric power plants and mining and metal production facilities and are characterized by intensive agricultural activity. [ABSTRACT FROM AUTHOR]

Five wild edible mushroom species, namely, Macrolepiota mastoidea, Macrolepiota konradii, Macrolepiota procera, Suillus collinitus and Cuphophyllus pratensis, were studied for their trace element contents by inductively coupled plasma - mass spectrometry (ICP-MS). The potential health risk assessments of children and adults were evaluated by the weekly intake (EWI), target hazard quotients (THQ), hazard index (HI) and cancer risk (CR). None of the analyzed elements exceeded the THQ value more than 1, but the HI values indicated that M. mastoidea and S. collinitus may be dangerous to children's health. The values of CR for As and Cd for children in all mushroom species were above 1X10-4 suggesting that there was a potential health risk. The CR values for adults suggest that all mushrooms may pose a threat to human health related to Cd. [ABSTRACT FROM AUTHOR]

The Cr, Mn, Cu, Se, Ni, As, Hg, Cd, Pb, Zn, and Fe levels in chicken, duck, and quail eggs from Jiangxi Province were determined by inductively coupled plasma mass spectrometry (ICP-MS), and the potential risks to human health were evaluated. The levels of trace elements from Jiangxi Province were not above the Chinese national standard. The target hazard quotient (THQ) values for the elements and total THQ for a combination of trace elements were <1, suggesting the absence of health risk from trace elements. The carcinogenic risks (CRs) of As, Cd, Cr, and Pb in all egg samples were negligible or within the acceptable range. These results demonstrate that trace element levels in eggs from Jiangxi Province of China were low and not associated with human health risk. In addition, levels of Fe and Zn were higher in quail eggs (30,166 and 172,356 lg.kg-1), chicken eggs (19,919 and 13,081 lg.kg-1), and duck eggs (27,123 and 14,422 lg.kg-1), suggesting that poultry eggs are good sources of trace elements essential to human health. [ABSTRACT FROM AUTHOR]

Metallic trace elements toxicity has been associated with a wide range of morphological abnormalities in fish, both in natural aquatic ecosystems and controlled environments. The bioaccumulation of metallic trace elements can have devastating effects on several aspects of fish health, encompassing physiological, reproductive, behavioural, and developmental functions. Considering the significant risks posed by metallic trace elements-induced toxicity to fish populations, this review aims to investigate the deleterious effects of prevalent metallic trace elements toxicants, such as mercury (Hg), cadmium (Cd), chromium (Cr), lead (Pb), arsenic (As), and copper (Cu), on the neurological, reproductive, embryonic, and tissue systems of fish. Employing diverse search engines and relevant keywords, an extensive review of in vitro and in vivo studies pertaining to metallic trace elements toxicity and its adverse consequences on fish and their organs was conducted. The findings indicate that Cd was the most prevalent metallic trace elements in aquatic environments, exerting the most severe impacts on various fish organs and systems, followed by Cu and Pb. Moreover, it was observed that different metals exhibited varying degrees and types of effects on fish. Given the profound adverse effects of metallic trace elements contamination in water, immediate measures need to be taken to mitigate water pollution stemming from the discharge of waste containing metallic trace elements from agricultural, industrial, and domestic water usage. This study also compares the most common methods for treating metallic trace elements contamination in water. [ABSTRACT FROM AUTHOR]

Research on finding the trace element in the fly ash material becomes imposing due to environmental effect. Coal fly ash formed from the burning of coal by thermal power plants are huge and it has been a big problem in its disposal. The main aim of this study is geochemistry of fly ash sample from Neyveli thermal power station. Mine-I has a reserve of 365 MT and covers an area of 26.69 sq. km. The tiny mine-IA, which has a reserve of 120 MT, is spread across an area of 11.6 sq. km. The Indian government has approved the expansion of the second Mine's capacity from 4.7 MT to 10.5 MT. Despite the above listed numerous studies, the behavior of trace elements are still incompletely understood and additional investigations are required. The current study is a thorough examination of trace elements in Neyveli lignite combustion bottom ash and pond ash. In the bottom ash and pond ash, the concentrations of 21 elements (As, Ba, Cr, Ag, Cd, Co, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Rb, Sr, Se, Ti, Zn, Zr, Sb, and Sn) were determined. [ABSTRACT FROM AUTHOR]

The consumption of contaminated river water can have severe effects on human health. This study aims to investigate the trace elements (TEs) content and their health risk assessment in the Badigad River Basin in the lesser Himalayas of Nepal. In total, 44 water samples were collected from 22 different sites during the pre-monsoon and monsoon seasons, and 25 TEs were analyzed. Correlation matrix and principal component analysis (PCA) were used to analyze the potential relationship between the measured TEs and their source tracking. Furthermore, the water quality index (WQI), metal index (MI), and cancer index (CI) were evaluated. The TEs content in all samples were found to be within the WHO recommended guideline for drinking and domestic purposes. The dominancy order of the TEs was observed as Sr > Ba > Li > Rb > Zn > Cr > Sc > Mn > Ti > Cu > As > Ni > Co > U > V > Pb > Cs > Ga > Y > Tl > Th > Zr > Bi > Cd > Nb. The PCA analysis suggested that TEs could have natural, anthropogenic, and mixed origins. The WQI indicated that the river water is safe from a human health perspective. The MI suggested that Badigad River can be considered safer for drinking purposes, and the cancer index (CI) showed that all the reported TEs are at low-risk levels. The findings of this study could be useful for government agencies in developing more sustainable water management policies in the region. However, it is suggested that further investigations should be conducted in terms of other hydrogeochemical variables, including major ions, at spatiotemporal levels for the sustainability of the river basin. [ABSTRACT FROM AUTHOR]

Sustainable river ecosystem is the fundamental backbone of all civilizations of the world. Water contamination through heavy metals and metalloids causes wide environmental and public discontent which makes it a global concern. With this view, 20 km stretch of Gomti River encompassing 5-locations was selected for determination of 16-physicochemical parameters and 11-heavy metals in water and bed-sediment samples during two consecutive years 2019–2020 covering three seasons supplemented by indices and statistics. Bed-sediment characterization was done through scanning electron microscope–energy dispersive X-rays and attenuated total reflection-Fourier transform infrared analysis. River is significantly contaminated with Fe, Mg, Mn, Zn, Pb, Cu, Ni, Cr, Co, Cd, Hg having corresponding mean values 10.1 ± 1.8, 31.7 ± 6.2, 1.4 ± 0.5, 0.42 ± 0.07, 0.09 ± 0.03, 0.03 ± 0.02, 0.17 ± 0.02, 0.41 ± 0.14,0.19 ± 0.01, 0.18 ± 0.01, 0.002 ± 0.001 mg/l in water and 3418.7 ± 529.9, 1839.9 ± 417.6, 194.3 ± 49.1, 112.2 ± 37.5, 42.5 ± 15.7, 36.1 ± 10.6, 23.4 ± 8, 16.7 ± 5.9, 8.4 ± 3.2, 8.2 ± 3.3, 0.002 ± 0.001 µg/g in bed-sediment, respectively. Corresponding order of heavy metals concentration was Mg > Fe > Mn > Zn > Cr > Co > Cd > Ni > Pb > Cu > Hg and Fe > Mg > Mn > Zn > Pb > Cu > Ni > Cr > Co > Cd > Hg, respectively. Higher values of indices for risk quantification; geo-accumulation index (5.0), contamination factor (1191.8), enrichment factor (46.5) and potential ecological risk index (393.8) were found for Cd in bed-sediment samples. Principal component analysis (λ > 1) scored 3-factors having 65%, 19% and 11% variance for water and 75%, 10% and 7% variance for bed-sediment samples. Strong positive correlations (≥ 0.8) were observed among Mn, Cd, Co, Cr, Pb, Cu for water and sediment samples. Study could be beneficial in providing knowledge regarding heavy metal induced ecological risk to aquatic organisms and suggest ways to reduce the burden of potential influx sources. [ABSTRACT FROM AUTHOR]

Ergene River contains many chemical substances and therefore, it has negative effects on the surrounding ecosystem and local people. To find a solution to these chemical substances and also to determine the adsorption performance of the activated carbon obtained from ripe black locust seed pods, the adsorption of various elements was studied on this activated carbon in Ergene River water sample. In Ergene River water sample, the adsorption performances of Mn, Cr, Ni, Co, Cd, V, Ti, Na, Mg, K, Ca, S, P, B, Pb, Cu, Zn, Sn, and Al on the activated carbon were studied under various operating conditions.For this aim, operating condition effects, such as adsorbent dosage, adsorption temperature, and contact time on these element adsorptions were investigated. 0.4 g activated carbon was found to be adequate for the above 90% removals of most elements from 50 mL Ergene River sample, and it was noticed that adsorption temperature differently affected adsorption performances of each element in the experiments at 25, 35, and 45°C. Also, the adsorption equilibriums of most elements in activated carbon/Ergene River solution were rapidly reached in first 5 min, but reaching adsorption equilibriums of Co, Sn, Mg, K, and Ca took more times (until 1500 min). Moreover, the desorption study of these elements from the activated carbon adsorbed with chemical substances in Ergene River sample was achieved by using HCl solutions with various concentrations of 0.1, 0.5, 1, 2, 3, 4, 5, and 6 M. As a result, the activated carbon obtained from ripe black locust seed pods displayed promising performance for the most elements, bad odour, and colour removals in Ergene River sample. [ABSTRACT FROM AUTHOR]

Currently, only 50% of concrete produced from construction and demolition waste is being recycled in Europe. This falls short of the European Union's target of 70% by 2020. Moreover, this figure only considers coarse fractions (>4 mm), as technical issues arise when using fine fractions. In pursuit of a complete circular life for recycled concrete, this investigation explores the potential use of fine fractions to enhance the physicochemical conditions and reduce the element concentration of acid mine drainage. Two trickling sets were prepared using a filter holder, with acidic waters passing through a layer of recycled concrete aggregates. Results revealed an immediate increase in water pH to neutral levels, a reduction in solution oxidation, and the complete, or near-complete retention, of potentially toxic elements by the substrate (with retention percentages of over 99.9% for Al and Fe, between 43.1% and 61.1% for S, over 91.1% for Zn, and over 99.1% for Cu). The experiment also showed a significant increase in Ca levels (tripling the initial value) and some Mg in the water, which could promote the subsequent precipitation of carbonates and the retention of trace metals. In summary, this study demonstrates the effectiveness of using recycled concrete aggregates in a laboratory setting. Further investigation is necessary to evaluate the feasibility of implementing this technique at the pilot scale. [ABSTRACT FROM AUTHOR]

This preliminary study focuses on three abandoned sites, located in the communes of Temuco, Villarrica, and Lonquimay, in the Araucanía Region, Chile. Two of the sites were classified as illegal landfills and one was a former landfill. Seventy-three surface samples were taken, of which 32 were from site S1, 20 were from site S2, and 21 were from site S3. The objectives of this study were (1) to establish the background values of trace metals present in soils through different statistical methods, (2) to determine the level of contamination and possible ecological risks in soils, and (3) to assess the health risk posed to children and adults from potentially hazardous elements (As, Ba, Cd, Co, Cr, Cu, Hg, Ni, Pb, V, and Zn). The data analyzed belong to a report presented by Chile's National Environmental Centre (CENMA). An evaluation was carried out through a multivariate statistical analysis to determine the type of origin and association of the trace elements, and spatial distribution maps were generated to establish the behavior of the contents of heavy metals present in the sites studied. The background values for sites S1, S2, and S3 were obtained by the median + 2MADdian absolute deviation) method. These values varied in the range of 14,702–41,785 mg kg−1 for Al, 0.83–8.9 mg kg−1 for As, 29.2–77.2 mg kg−1 for B, 59.2–143 mg kg−1 for Ba, 10.1–22.8 mg kg−1 for Cd, 18.4–51.2 mg kg−1 for Co, 12.3–38.0 mg kg−1 for Cr, 47.8–76.6 mg kg−1 for Cu, 36,230–64,274 mg kg−1 for Fe, 0.02–0.05 mg kg−1 for Hg, 482–4396 mg kg−1 for Mn, 16.7–19.3 mg kg−1 for Ni, 1.0–17.6 mg kg−1 for Pb, 1.4–28.2 mg kg−1 for Se, 108–258 mg kg−1 for V, and 68.1–145 mg kg−1 for Zn. In terms of ecological risk, the geoaccumulation index (Igeo), enrichment factor (EF), and contamination factor (Cf) values for As and Se at site S1, As at S2, and Pb with As at S3 were the main elements indicating the highest contamination levels, as well as a higher number of samples with contaminated content. The Potential Ecological Risk Index (PERI) revealed that on average, there was a moderate ecological risk for S1 and S2 and a considerable ecological risk for S3; the main contributions were generated by As and Hg in S1 and S2, while, in S3, they were produced by Pb and As. In terms of the risk to human health, the risk was higher in children than in adults, with the ingestion route as the main source of risk. For adults, it was found that there was no likelihood that they would develop any adverse non-carcinogenic or carcinogenic health effects. In contrast, children were found to be more likely to sustain adverse health effects. Regarding the non-carcinogenic risk to children, the Co and As samples at S1, S2, and S3, and the Pb at site S3 showed values exceeding the non-carcinogenic-risk limit. Regarding the carcinogenic risk, all three sites studied had Cd samples that indicated a likelihood of children developing cancer from this heavy metal. [ABSTRACT FROM AUTHOR]

Metallogenic models are vital to mineral exploration. However, there is debate concerning the origin of hydrothermal‐type ore deposits such as vein‐type U and W deposits. The formation, migration, heating and controls on the composition of metal‐fertile fluids in active geothermal systems provide insights into the formation of ore‐forming fluids. Fluid's metal contents are relatively high in the Yadong–Yangbajing–Naqu (YYN) geothermal belt of South Tibet, and a similar association of enrichment has been found in saline lakes of the region. This study analysed major ions and trace metal contents together with stable (O, H) isotopes of water samples from geothermal springs and wells and regional saline lakes and rivers along the Beng and YYN fault systems. Results demonstrate that metal‐fertile geothermal brines, were sourced from the Bangor saline lake. This study highlights the role of evaporation of saline lake water in the formation of metal‐fertile brines and the contrasting behaviors of U and W in hydrothermal conditions. [ABSTRACT FROM AUTHOR]

Over the past decade, heavy metal (HMs) contamination in soil environments has become severe worldwide. However, their resulting ecological and health risks remained elusive across a variety of soil ecosystems due to the complicated distributions and sources. This study investigated the HMs (Cr, As, Cu, Pb, Zn, Ni, Cd, and Hg) in areas with multi-mineral resources and intensive agricultural activities to study their distribution and source apportionment using a positive matrix factorization (PMF) model coupled with self-organizing map (SOM). The potential ecological and health risks were assessed in terms of distinct sources of HMs. The results disclosed that the spatial distribution of HM contaminations in the topsoil was region-dependent, primarily located in areas with high population intensity. The geo‑accumulation index (Igeo) and enrichment factor (EF) values collectively displayed that the topsoils were severely contaminated by Hg, Cu, and Pb, particularly in residential farmland areas. The comprehensive analysis combined with PMF and SOM identified both geogenic and anthropogenic sources of HMs including natural, agricultural, mining, and mixed sources (caused by multi-anthropogenic factors), accounting for 24.9%, 22.6%, 45.9%, and 6.6% contribution rates, respectively. The potential ecological risk was predominantly due to the enrichment of Hg, followed by Cd. The non-carcinogenic risks were mostly below the acceptable risk level, while the potential carcinogenic health risks caused by As and Cr should be paid prime attention to, particularly for children. In addition to the 40% geogenic sources, agricultural activities contributed to 30% of the non-carcinogenic risk, whereas mining activities contributed to nearly half of the carcinogenic health risks. [ABSTRACT FROM AUTHOR]

The impact of population expansion through economic growth and development has been identified as one of the key drivers of both water and sediment contamination from potentially harmful elements (PHEs). This presents a major hazard not only to aquatic ecosystems but local riparian communities and beyond who rely heavily on this natural resource for drinking water and fish—a valuable source of dietary micronutrients and protein. The present study measured biogeochemical concentration of PHEs in water, sediment and fish from locations pooled into four zones within Winam Gulf and Lake Victoria area of Kenya. Captured fish were used as a sentinel receptor of lake health to evaluate potential risks to fisheries and aquaculture food security. In water, concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu) and lead (Pb) were observed above the United States Environmental Protection Agency (US EPA) maximum contamination level drinking water guidelines (MCL), with aluminium (Al) observed above the Aquatic Life Criteria in all four zones. Similarly, sediment concentrations in all four zones exceeded the US EPA Effects range low (ERL) threshold guidelines for Cu, nickel (Ni), zinc (Zn) and Pb, with Cu, Zn and Pb classed at moderate contamination levels using the contamination factor. Fish tissue concentrations from the four zones were calculated using recommended daily intakes (RDI) and for PHEs as provisional maximum tolerable intakes (PMTIs) and indicated most macro- and micronutrients were at or below 10% RDI from aquaculture and wild fish, with Se indicating a greater RDI (16–29%) in all the zones. Contributions of PHEs to PMTIs were below threshold guidelines for both aquaculture and wild fish with only Cd, Cr and Pb levels being above the PMTI thresholds. There is a need to assess the long-term effects of persistent anthropogenic PHE input into Winam Gulf and the wider Lake Victoria basin. Continued monitoring of PHEs using both historical and more recent data will enable future management policies to be implemented through improved mitigation strategies to reduce their impact on water quality, fish health and subsequent human health. [ABSTRACT FROM AUTHOR]

In this research, the effect of flooding caused by heavy precipitation, postulated to be one of the consequences of climate change, on toxic metal concentrations in two demersal fish species, whiting (Merlangius merlangus euxinus) and red mullet (Mullus barbatus), was investigated. For both demersal fish species, concentrations of Hg, Fe, Cd, Pb, Se, Al, Zn, Cu, Sr, B, Cr, Mn, Ni, Ba, and Li were compared between samples taken from Türkeli, Sinop, Black Sea, before and after the flood event in August 2021. Hg, Mn, Se, Li, B, and Sr metal concentrations increased in whiting and in red mullet in the post-flood samples. Estimated daily intake, target hazard quotient, cancer risk, the maximum allowable daily consumption rate and minimum daily requirements, and health risk analyses indicated that daily consumption of whiting and red mullet was risky due to the heavy metal Hg level after the flood. In addition, it was found that the samples had higher levels of Se than Hg, Se/Hg ratios were above 1, and Se-HBV were positive. Therefore, whiting and red mullet fishing should be restricted for a limited time period in the region. [ABSTRACT FROM AUTHOR]

Nowadays, the problem of inland water pollution is acute. It is caused by vast industrial growth and agricultural intensification. Concentrations of Cd, Pb, Zn, Cu, Mn, Fe, Mg, and Kwere determined in the muscles, liver, and gonads sabrefish from Rybinsk Reservoir areas with different anthropogenic loads. The tissue samples were analyzed by atomic absorption spectrometry. Heavy metals accumulated more intensively in the body of fish from more polluted areas of the reservoir. Among the analyzed elements, the maximum accumulation levels were found for K, Zn, and Fe and the minimum levels were observed for Cd and Pb. The gonads contained the largest concentration of Cd and Mn, the muscles contained the highest concentrations of Mg, and the other elements mainly accumulated in the liver of sabrefish. The THQ and HI values for all elements did not exceed 1, which suggests that there is no potential non-carcinogenic risk to human health. The target values of carcinogenic risk (TR) for cadmium ranged from 8.32 × 10−6 to 1.22 × 10−4 in the muscles. The increased content of cadmium in the gonads of sabrefish not only poses a risk to human health, but also to the reproduction of this species in the Rybinsk Reservoir. [ABSTRACT FROM AUTHOR]

Mining has brought many environmental problems to the surrounding soil, water, and air, with toxic elements contaminating surface water, threatening ecological balance and human health. This study selected the Wenyu watershed downstream from a large molybdenum mine in the Qinling Mountains as the study area, aiming to explore the impact of molybdenum mining on surface water quality. The content characteristics of Cd, Pb, Cu, Cr and Hg in surface water, sediment, and rock samples were analyzed by field sampling and chemical testing. The results showed only obvious Cd pollution. The pollution status and ecological risk level of surface water and sediment samples in the Wenyu Stream watershed were evaluated using the single pollution index method, geo-accumulation index method, and Hakanson potential ecological risk assessment method. Finally, the sources of Cd pollution and the impact of mining on Cd distribution in the Wenyu Stream were comprehensively discussed. The research results showed that Cd content in the Wenyu Stream was significantly affected by mining activity and the coefficient of variation of Cd content reached 99.44%. Among 22 surface water samples, 21 samples met the Class II water standard, indicating a clean overall water quality of the Wenyu Stream, and only one sample exceeded the Class II water standard with a mild pollution level. All 15 sediment samples were polluted to varying degrees and the most severely polluted sample had reached a moderate to strong pollution level. Most of the samples were at a moderate pollution level. The potential ecological hazard indexes of Cd content were at medium to very strong risk level, indicating that the overall sediment in the main ditch of the Wenyu Stream was under a strong ecological risk level. The main sources of Cd pollution, including acid mine drainage, regional geological background, sediment release, and atmospheric dry and wet deposition, were discussed. [ABSTRACT FROM AUTHOR]

Nowadays, clean-up of heavy metals from wastewaters using waste residue carbon-based material has received increasing attention. In this work, a novel Chinese medicine residue carbon-based nano zero-valent iron composite (CM-nZVI) had been successfully prepared using the combined Chinese medicine residue, FeCl3 and green tea extract. Cr(VI) and/ or Cd(II) removal in water by the CM-nZVI were systematacially investigated with a series of batch experiments. The most relevant findings indicated the adsorption efficiecy and capacity of Cr(VI) by CM-nZVI were respecitvely nearly 98% and 26 mg/g under optimized reaction conditions. The negative influences of the cations on the Cr(VI) removal followed the order of Al3+ > Ca2+ > Mg2+ Na+ > K+, but the anions followed the order of HCO3− > PO43− > NO3− > Cl− > SO42−. Humic acid (HA) and ionic strength with high concentrations severely inhibited Cr(VI) removal. The Cr(VI) adsorption on CM-nZVI fitted well by the pseudo-second-order kinetic and Langmuir models. A monolayer endothermic chemisorption occurred on Cr(VI) adsorption over CM-nZVI, and Cr(VI) removal by CM-nZVI primarily involved in the absorption, reduction, precipitation and complexation processes. Both Cr(VI) and Cd(II) removals had been achieved by CM-nZVI at their low concentrations. This CM-nZVI showed a better reusability proprity for Cr(VI) and Cd(II) removal with the regeneration of CM-nZVI through simple pickling. The outcomes of this work show that CM-nZVI could be used an effective material for heavy metals removal from water. [ABSTRACT FROM AUTHOR]

In order to realize the simultaneous removal of nine metal ions from water, in this study, an excellent flocculant suitable for the simultaneous removal of multiple metal ions in water was developed by using the excellent flocculation properties of graphene oxide (GO) combined with biological flocculants. First, this study investigated the concentrations and pollution levels of nine metal pollutants in surface water and groundwater of a typical city in central China. The maximum concentrations of these nine metal ions were Al 0.29, Ni 0.0325, Ba 0.948, Fe 1.12, As 0.05, Cd 0.01, Zn 1.45, Mn 1.24, and Hg 0.16 (in mg/L). Second, the three-dimensional structure diagram of GO was established. Gaussian16W software and the pm6D3 semi-empirical method were used to analysis the structure and the vibration of GO. The B3LYP function and basis set DEF2SVP was used to calculate the single point energy. Third, with varying the flocculation time, it was found that the maximum flocculation efficiency could reach more than 80.00% under the optimal conditions, that is, with a metal ion mixture of 20 mg/L. The optimal dosage of GO was 15 mg/L. The optimal time for bioflocculation efficiency was 2.5 h, and the optimal concentration of bioflocculant was 3 mg/L. The optimal flocculation efficiency was 82.01% under the optimal conditions. [ABSTRACT FROM AUTHOR]

Natural thermal and mineral waters are widely distributed along the Hellenic region and are related to the geodynamic regime of the country. The diverse lithological and tectonic settings they are found in reflect the great variability in their chemical and isotopic composition. The current study presents 276 (published and unpublished) trace element water data and discusses the sources and processes affecting the water by taking into consideration the framework of their geographic distribution. The dataset is divided in groups using temperature- and pH-related criteria. Results yield a wide range of concentrations, often related to the solubility properties of the individual elements and the factors impacting them (i.e. temperature, acidity, redox conditions and salinity). Many elements (e.g. alkalis, Ti, Sr, As and Tl) present a good correlation with temperature, which is in cases impacted by water rock interactions, while others (e.g. Be, Al, Cu, Se, Cd) exhibit either no relation or an inverse correlation with T possibly because they become oversaturated at higher temperatures in solid phases. A moderately constant inverse correlation is noticed for the vast majority of trace elements and pH, whereas no relationship between trace element concentrations and Eh was found. Seawater contamination and water-rock interaction seem to be the main natural processes that influence both salinity and elemental content. All in all, Greek thermomineral waters exceed occasionally the accepted limits representing in such cases serious harm to the environment and probably indirectly (through the water cycle) to human health. [ABSTRACT FROM AUTHOR]

Port and industrial activities often cause contamination of estuarine sediments, yet information on sediment metal contamination in Richards Bay Harbour is limited. This study examined the extent and ecological relevance of metal contamination using sediment quality guidelines, pollution indices, macrobenthic community structure and the biotic index M-AMBI. Sediment samples for metal and macrobenthic analyses were collected quarterly at seven sites during 2016−2017 using a Van Veen sediment grab sampler. Sediment samples were acid digested using a microwave digester and analysed for metal concentrations using ICP-OES. Highest metal concentrations (Cd, Cr, Cu, Ni and Zn) were associated with areas most affected by industrial activities, while concentrations of most metals at the remaining sites were low. Pollution indices confirmed significant enrichment of Cd, Cr and Cu in bulk terminal sediment. Sediment quality guidelines revealed potential toxicity associated with Cu, Cr and Ni. The dominant taxa were Halmyrapseudes digitalis (two sites), Mediomastus capensis (three sites) and Sigambra parva (two sites). A significant inverse correlation existed between pollution indices and M-AMBI scores, confirming the adverse effect of metals on habitat quality. The need for a biomonitoring programme incorporating relevant biotic and abiotic indices is emphasised to assess the long-term effects of sediment contamination on aquatic communities in South African estuarine environments. [ABSTRACT FROM AUTHOR]

The knowledge of migratory connectivity is important for understanding the potential drivers of populations and it is thus important for conservation implications. Migratory connectivity of species can be studied using exogenous, such as rings and transmitters, or endogenous markers, such as stable isotopes and trace elements. The use of trace elements has been much less frequently studied compared to stable isotopes. Trace elements can be studied from the feathers of birds and this does not necessarily require trapping of individuals. Here we studied the variation of 18 different trace elements in feathers of two long‐distance trans‐African migrants, willow warblers Phylloscopus trochilus and barn swallows Hirundo rustica, using body feathers of museum specimens of birds from Finnish breeding grounds. The trace elements were measured using laser‐ablation inductively‐coupled‐plasma mass‐spectrometry (LA‐ICP‐MS). We show that trace element concentrations were relatively stable along the rachis within the same feather except in Ni and S, which showed a quadratic pattern. In general, variation within feathers of the same individuals was smaller than in feathers between individuals for most elements. Furthermore, concentrations of 11 trace elements showed significantly higher concentrations in willow warbler feathers collected in spring than in autumn, moulted in African wintering grounds and European breeding grounds, respectively. Last, concentrations of seven trace elements were significantly higher in the spring feathers of willow warblers compared to barn swallows. This suggests that trace elements could be used to separate moulting grounds of the birds on the larger scale within the same species, but also sampling design should be carefully considered. [ABSTRACT FROM AUTHOR]

Preserving the ecological health of wetlands has enormous importance in an arid climate. Manchar Lake, located in the arid part of Pakistan, is one of the most vulnerable freshwater lakes and has continuously been exposed to direct pollutants influx. Its vulnerability demands an assessment of pollution loads of trace elements in bed sediments. This study was carried out with sediment samples from 21 locations. Nine trace elements (As, Pb, Fe, Cr, Hg, Cu, Ni, Mn, and Zn) were detected using Inductively Coupled Plasma Mass Spectrometry. Pollution load-related analytical approaches were applied to estimate the contamination loads of individual elements and the aggregated ecological risks. Overall, the mean concentrations of all trace elements in lakebed sediments were detected as: As 5.4, Pb 2.2, Cr 17, Cu 1.5, Fe 165.1, Hg 0.028, Mn 2.6, Ni 7.5, and Zn 64.9 in mg/kg. Results revealed that the lakebed sediment is significantly polluted, primarily with Fe, Zn, Hg, Cr, and As. The spread of these trace elements also varies across locations as many locations do not receive polluted water during dry seasons due to the low water level in the lake. The ecological risk assessment and multivariate analysis findings establish that the Main Nara Valley Drain comprising drainage water from agricultural fields and in part from municipalities is the greatest pollution source to the lake. This dangerous pollution problem calls for action to restore the purity of the natural lake ecosystem. [ABSTRACT FROM AUTHOR]

Goa, a biodiversity hotspot, is also a major iron ore producing state in India. This study investigated total heavy metal (HM) contamination in 65 georeferenced soil samples through inductively coupled plasma atomic emission spectrophotometer (ICP-AES) for assessing risk of mining activity on agricultural soils. The mean concentrations of copper (Cu), zinc (Zn), lead (Pb), nickel (Ni), chromium (Cr), cadmium (Cd), manganese (Mn), iron (Fe) and cobalt (Co) were 125.60, 75.60, 96.40, 51.20, 69.30, 25.77, 2091, 162638 and 21.20 mg kg−1, respectively. Lower pH, higher organic carbon (OC) and fine-textured soil augmented metal accumulation processes. Boxplot of geoaccumulation index (Igeo) values indicated that lead (Pb) metal had more variation in the study area. Mean Igeo values of metals in descending order are Fe (4.24) > Mn (3.08) > Cu (2.84) > Co (2.47) > Pb (1.85) > Cd (0.7) > Zn (0.58) > Ni (0.45) > Cr (0.16). Mean values of modified degree of contamination (mCdeg) (10.4) and pollution load index (PLI) (6.19) revealed high contamination with deteriorating soil quality. Combined approach of correlation, principal component (PC) and cluster analysis indicated the source of origin by describing association of metals with Fe. PC biplot showed that impact of mining was more on lowland agro-ecosystem rather than natural due to slope factor which led to clogging of pores by mining overburden mixed soil deposition from uphill as evidenced from the presence of waterlogged fallow lands. Fuzzy k-mean clustering yielded three contamination zones (CZs) of low (CZ2), moderate (CZ1) and high (CZ3) degree of contamination. The CZs-based site-specific land management plan might lead to a sustainable ecosystem through coexistence of both mining and agricultural activity by arresting contamination and restoring fallow lands. [ABSTRACT FROM AUTHOR]

The present study investigated the distribution, sources, bioavailable fractions, and ecological risks of nine metals (Al, Cd, Co, Cr, Cu, Fe, Mn, Pb, and Zn) in water, sediment, and vegetation samples collected from a shallow lake within the industrial town of Ranipet, India. The lake water samples exceeded the concentrations of Al, Cd, Cr, Cu, Fe, Mn, and Pb beyond BIS (Bureau of Indian Standards) limits for drinking water with Cr to be highest as 6.73 mg/L. The Geo-accumulation index for lake bed sediment samples were in the order of Cr>Cu>Co>Mn>Zn>Pb. The bioavailability of the metals in sediment samples determined through Sequential Extraction Procedure (SEP) showed Cr>Co>Zn>Cu>Pb>Mn>Fe>Al. The sediment samples collected from the root zone of different plant species (Cynodon dactylon, Sida acuta, and Eclipta prostrata) exhibited varied bioavailable fractions than lake bed sediments, which indicated the influence of plants in mobilising and fixing the metals. The plant samples had metals concentration in the order of Root>Stem>Leaves and showed the possibility of phytoremediation. Principle Component Analysis (PCA) and Pearson Correlation Matrix (PCM) in the lake bed sediment samples identified the clustering of Al and Fe which indicated probable lithological origin. The lone clustering of Cr from Co, Mn, and Cu indicated separate anthropogenic sources. Further Al, Fe, and Mn showed strong correlations with TOC (Total Organic Carbon) substantiate their distribution under influence of TOC. The study indicated elevated metals pollution is water, sediment, and plants samples from lake area which require immediate attention from all the stakeholders. The assessment of pollution in small and shallow lakes amidst industrial belts need to be prioritised as they often become victims of industrial encroachment and cease to exist in long run. [ABSTRACT FROM AUTHOR]

The Changpo–Tongkeng tin polymetallic deposit in Dachang, Guangxi, is a world-class, superlarge, polymetallic tin deposit consisting of lower skarn zinc–copper ore bodies and upper tin polymetallic ore bodies. Garnet is the main gangue mineral in the skarn zinc–copper ore bodies and has a granular texture. Based on hand specimens and microscopic observations, the existing garnet can be divided into two generations: an early generation (Grt I) and a late generation (Grt II). The results of electron probe microanalysis (EPMA) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) in situ microanalysis show that the contents of SiO2 and CaO in the garnets from the two generations present limited variations, while the FeOT and Al2O3 contents vary significantly, indicating the grossular–andradite solid solution series (Gro29–82And12–69). Compared with Grt I (Gro72And25), Grt II (Gro39And59) is Fe-enriched and oscillatory zoning is developed. The total rare earth element (REE) contents in the two generations of garnet are relatively low, showing light rare earth element (LREE) depletion and heavy rare earth element (HREE) enrichment patterns. Grt II has higher REE content than Grt I and exhibits significant negative Eu anomalies (δEu = 0.18–0.44). The contents and variation characteristics of the major and trace elements in the two generations of garnet suggest that there were variable redox conditions and water/rock ratios in the hydrothermal system during the crystallization process of garnet. In the early stage, skarnization was in a relatively closed and low-oxygen fugacity system, with hydrothermal diffusion metasomatism being dominant, forming homogeneous Grt I lacking well-developed zoning. In the late stage of skarnization, the oxygen fugacity of the ore-forming fluids increased, with infiltration metasomatism being dominant, forming Grt II with well-developed oscillatory zoning. The contents of Sn, As, W, In, and Ge in the garnets are relatively high and increase with the proportion of andradite. Sn in zinc–copper ore bodies mainly exists in the form of isomorphic substitution in garnet, which may be the main reason for the lack of tin ore bodies during the skarn stage. This paper compares the trace element contents in garnets from domestic skarn deposits. The results indicate that the Sn content and δEu in garnet can be used to evaluate the tin-forming potential of skarn deposits. [ABSTRACT FROM AUTHOR]

Selected Malaysian black shale sequences of the Permo-Triassic and Devonian ages that crop out in the Central Belt were investigated to discuss their chemical composition, provenance, tectonic setting, and weathering history. X-ray fluorescence (XRF) analysis shows that the BRSZ Unit 1 black shale has elevated SiO2, TiO2, and K2O contents compared to the Semantan and Gua Musang black shale. In terms of trace elements, the BRSZ Unit 1 black shale has elevated trace element contents compared to the Semantan and Gua Musang black shales. The BRSZ Unit 1 has the highest V, U, Pb, and Mo contents relative to the other two formations. The Mo content is significant in the BRSZ Unit 1 and is thought to be associated with the elevated total organic carbon (TOC) in the BRSZ Unit 1 black shale. Compared to Post-Archean Australian Shale (PAAS), the BRSZ Unit 1 and Gua Musang black shales are low in Fe2O3, MnO, CaO, Na2O, and P2O5. The Semantan black shales are deficient in CaO, K2O, and P2O5 and enriched in MnO. The black shales of BRSZ Unit 1 are enriched in V, Cu, Ga, Rb, Mo, Sn, Pb, and U. Except for Pb (mean: 32.3 ppm), the Gua Musang black shales are largely depleted in trace elements. Similar to the Semantan black shales, all trace element concentrations are largely depleted with the exception of Sc (mean: 22.3 ppm), which is slightly higher. Provenance analysis shows that the BRSZ Unit 1, Semantan, and Gua Musang black shales derived from felsic and intermediate parental source rocks. The BRSZ Unit 1 and Gua Musang black shales indicate a collision setting, whereas the Semantan black shales show affinity to a continental arc setting. The CIA values for all the samples analyzed in this study range between 79.4 and 95.8, indicating an intense chemical weathering in warm and wet paleoclimatic conditions. The average CIW values of samples from the BRSZ Unit 1, Semantan, and Gua Musang are 99.4, 94.5, and 98.6, respectively, implying an intense degree of weathering of the source rocks. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the levels of major (Na, Mg, K, Ca) and heavy (Cr, Mn, Fe, Ni, Cu, Zn, Cd) metals and health risk assessment of the peel, flesh and seed of pumpkins cultivated in Ethiopia, using microwave plasma-atomic emission spectrometry. Dried powdered samples (0.5 g) were wet digested with 69% HNO3 and 30% H2O2 in microwave digester. The percent recovery for the three parts of pumpkin samples were 90-110%. The mean concentration of metals in pumpkin peel, flesh, seed samples, respectively, were K (27806±9767, 29531±2452, 10667±1133), Ca (5267±2092, 3190±900, 2919±397), Mg (4716±469, 848±349, 4668±413), Fe (158±29, 111±46, 225±56), Na (167±116, 63.1±15, 171±123), Mn (28.9±1.4, 9.61±3.2, 33.4±4.9), Zn (24.2±4.4, 10.6±4.0, 67.5±12.3), Cu (8.14±1.1, 15.1±9.3, 10.8±0.9), Ni (3.79±2.4, 2.14±1.3, 3.44±2.8), Cr (0.28±0.1, 0.36±0.2, 0.69±0.1), Cd (0.24±0.1, 0.46±0.1, 1.39±0.2) mg/kg. The hazard index (HI) of pumpkin flesh and seed indicated ingestion of pumpkin is safe from non-carcinogenic risk. The total cancer risk (CR) due to consumption of pumpkin flesh and seed through Cr and Cd from the three sampling sites are in the range 1.1 x 10-4 -1.8 x 10-4, indicating a non-risk of exposure to cancer due to the consumption of pumpkin grown in the sampling areas. [ABSTRACT FROM AUTHOR]

Dashan Village area is one of the representative areas in China with high selenium concentration in the natural environment. A total of 133 topsoil samples have been collected in the Dashan Village area to explore the potential toxic elements (PTEs) background concentrations in soils under different land-use types for a comprehensive PTEs risk assessment (arsenic, cadmium, chromium, copper, mercury, nickel, lead, selenium and zinc). The results show that the geometric mean concentrations of As, Cr, Cu, Hg, Ni, Pb, Se and Zn found in the soil of the Dashan Village area were lower than the control standard for soil contamination risk in agricultural land. However, the geometric mean concentrations of Cd exceeded their corresponding standard values. For different land-use types, geometric mean concentrations of As, Cd, Cu, Hg, Ni and Pb in the arable soils were higher than in woodland soils and tea garden soils. Based on the potential ecological risk assessment, the woodland, arable and tea garden were at low-risk levels. Cadmium posed the highest ecological risk, while the other PTEs were of low risk in soils. Multiple statistical analyses and geostatistical analysis indicated that the concentrations of Cr, Ni, Pb, Cu, Zn and Se originated mainly from natural sources, while the concentrations of Cd, As and Hg could be influenced by anthropogenic activities. These results provide scientific support for the safe utilization and ecological sustainability of selenium-rich land resources. [ABSTRACT FROM AUTHOR]

Percolation of toxic metals existing in fly ash is the prime source of subterranean water contamination in the locale areas near industrial units. In this regard, a field survey was done in the vicinity of Rosa Thermal Power Plant situated in the Shahjahanpur district of Uttar Pradesh, India to examine the natural vegetation particularly aquatic ferns growing naturally in fly ash (FA) contaminated water bodies. It was observed that four aquatic ferns namely Marsilea minuta, Salvinia molesta, Ceratopteris thalictroides, and Azolla filiculoides were growing in the target site in which Azolla biomass has been found enduring and flourishing dominantly near the banks of Garrah River adjoining to the thermal power plant. The result of physicochemical studies of FA polluted water bodies revealed that the concentration of Cd, Cr, Pb, Al, Ni, Si, Mn, and Cu were 42.3, 41.1, 40.1, 4615, 204, 5600, 70 and 58.6 (μg/g) which are significantly high in comparison to the control (reference) site in which Cd, Cr, Pb, Al and Si are below detection limit and Ni, Mn, and Cu were 23.8, 45.8 and 25.4 (μg/g) respectively. Similarly, the metal content of collected Azolla filiculoides was significantly higher than the control site. Metal content (μg/g) in Azolla was found according to following pattern: Fe (61400) ˃ Si (9400) ˃ Cr (7900) ˃ Ni (6100) ˃ Cu (5600) ˃ Pb (4900) ˃ Zn (4600) ˃ Al (3800) > Mn (3200) > Cd (2700) > B (1100). The total chlorophyll was heavily decreased by 58.33 (%) in FA contaminated site in comparison to the control site. The result of antioxidant enzymes like MDA, SOD, and GPX was found to increase by 73.38 (%), 47.56 (%), and 80.75 (%) respectively in Azolla biomass growing in polluted water bodies due to the generation of oxidative damage by free radicals. However, the plant was not showing any visual phytotoxic symptoms. Therefore, it indicates that the Azolla filiculoides has the capability to withstand FA-induced metal toxicity and it may prove an ideal candidate to detoxify FA-contaminated water bodies. [ABSTRACT FROM AUTHOR]

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Fish constitutes the main protein source for the Amazonian population. However, the impact of different anthropogenic activities on trace element and metal accumulation in fish and their risks for human health at a regional scale remain largely unexplored. Here we assessed exposure levels of 10 trace elements and metals (Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, Pb, and Hg) in 56 samples belonging to 11 different species of fish from the Brazilian Amazon. We studied the relationship between exposure levels, fish origin, and fish feeding habits, and assessed toxicological and carcinogenic risks for the Amazonian population. No significant correlation was found between sampling site and exposure levels to the studied elements, but a significant difference was found between the accumulation of some metals and the position of the fish species in the food chain. The concentrations of Cr and Hg in fish flesh were found to exceed the Brazilian limits for human consumption. This study shows that current fish consumption patterns can lead to estimated daily intakes of Hg, As and Cr that exceed the oral reference dose, thus posing a toxicological concern. Furthermore, carcinogenic risks may be expected due to the continued exposure to Cr and As. The results of this study show that the consumption of wild caught fish in the Amazon region should be controlled. Moreover, continued monitoring of trace element and metal contamination in fish and on the health of the Amazonian population is recommended, particularly for riverine and indigenous communities. [Display omitted] [ABSTRACT FROM AUTHOR]

Trace elements pollution is a current One Health problem, affecting the health of all living beings (including humans and animals) and the environment itself. Metal(loid)s (as As, Cd, Co, Cu, Hg, Pb, and others) represent hazardous substances with implications in different organs and organic functions, in both acute or chronic exposures. The use of animal species as biomonitoring tools has been pointed out as an essential piece to correctly monitor and evaluate this pollution worldwide. Hedgehogs have been used for this purpose although in very few locations, despite the notable potential they have, due to several biological and ecological characteristics. Their food regiment (mainly insectivorous), distribution, resilience, trophic level and adaptability represent some examples of those positive aspects. This review intends to briefly summarize these hedgehogs' attributes and critically analyse them as positive aspects that turn this species into a suitable bioindicator of exposure and effects of heavy metal(loid) pollution. [ABSTRACT FROM AUTHOR]

In this study, authors also observed that copper (Cu) and Pb concentrations in spider webs had a positive correlation with levels of these metals in spiders' bodies. A classic case is mercury (Hg) bioaccumulation and biomagnification, which can compromise the entire food web and reach humans via consumption (Förstner & Gottfried, [9]). Regardless of the comprehensive attention given to emerging contaminants, classic contaminants such as metals continue to compromise the conservation of land, freshwater, polar, and coastal environments. [Extracted from the article]

Globally, the hazardous substance in children's goods is of great concern. Toxic chemicals are potentially harmful to the health and growth of infants and children. Lead (Pb) and cadmium (Cd)-contaminated children's jewelry is widely encountered in many countries. This study aims to determine the concentration of metal toxicants (Pb, Cd, Ni, Cu, Zn, Co, and Fe) in event-based (Independence Day festival) children's jewelry, considering time-limited and fast production products that may compromise the quality and safety parameters during manufacturing. The determinations are for the time-constraint industrial production of children's jewelry in the context of the toxic substances in a variety of base materials used. This is the first time event-based children's jewelry has been monitored and critically assessed for metal contamination. Forty-two samples, including metallic, wooden, textile, rubber, plastic, and paint-coated plastic children's jewelry, were tested. Seventy-four percent of samples detected Pb and Cd in quantifiable amounts. Ni in 71%, Cu in 67%, Co in 43%, and Zn and Fe were detected in 100% samples with quantifiable amounts. Twenty-two ID-CJ samples exceeded the US regulatory limit for Pb and four samples for Cd. However, twenty-nine samples for Pb, eleven for Cd, five for Co, and one for Cu exceeded the EU regulatory limit. The highest concentration of Pb was found in paint-coated plastic jewelry, and the highest Cd was found in metallic jewelry. These results suggest that the potential hazards of event-based children's jewelry deserve the attention of government agencies seeking to limit children's exposure to toxic chemicals. Intergovernmental organizations and individual countries regulate chemicals in consumer products, but a coordinated international approach is lacking. Some continents and countries still lack in regulations for children's products, especially jewelry, and toys. [ABSTRACT FROM AUTHOR]

This study measured concentrations of trace elements (Al, As, Cd, Cu, Fe, Mn, Ni, and Pb) in the muscle of pink shrimps (genus Penaeus) from two anthropized estuarine systems in Brazil: Guanabara Bay (GB) and Sepetiba Bay (SB). Concentrations were highest in the less anthropized SB site, where shrimps showed higher assimilation rates that can be explained by their higher trophic position compared to shrimps from GB. These results reinforce the role of food sources as the main route of trace elements for the aquatic animals. [ABSTRACT FROM AUTHOR]

The effect of previous frozen storage (−18 °C for 6 months) and different coating media (aqueous: water and brine; oily: sunflower, refined olive, and extra-virgin olive oils) on the essential macroelement and trace element content of canned Atlantic mackerel (Scomber scombrus) was studied. Previous frozen storage led to an increased (p < 0.05) content of canned samples of K (oil-coated samples) and Ca (all coating conditions) and to a decreased (p < 0.05) content of P (aqueous-coating samples) and S (water- and oil-coated samples). For trace elements, a content increase (p < 0.05) in Cu and Se (brine-canned samples) and Mn (water- and refined-olive-oil-coated samples) was detected in canned fish muscle with frozen storage. Concerning the coating effect, aqueous-coating samples showed lower (p < 0.05) Mg, P, S, K, and Ca contents than their corresponding oil-coated samples. For trace elements, lower average contents were found for Co, Cu, Mn, Se, and Fe in aqueous-coating fish muscle when compared to their counterparts coated in oily media. Content changes in the different elements in canned fish muscle are discussed based on interactions with other tissue constituents and modifications that such constituents undergo during processing (i.e., protein denaturation, liquor losses from the muscle, lipid changes). [ABSTRACT FROM AUTHOR]

Populus species are well documented for being potentially suitable for phytoremediation purposes regarding their accumulation characteristics. However, published results are contradictory. Based on the data gathered during an extensive literature search, we aimed to assess and revise the metal accumulation potential in the root, stem, and leaf of Populus species growing in contaminated soils, with meta-analysis. We evaluated the influences of pollution level, soil pH, and exposure time on the metal uptake patterns. We found accumulations of Cd, Cr, Cu, Pb, and Zn to be significant in each plant part, while that was only moderate for Ni, and limited for Mn. By calculating the soil pollution index (PI), we observed significantly intensive, PI-independent accumulation for Cd, Cr, Cu, Ni, Pb, and Zn. A decrease in soil pH significantly increased the uptake of Mn and significantly decreased the accumulation of Pb in the stem. Metal uptake was significantly influenced by exposure time as well; Cd concentration was significantly decreased in the stem, while concentrations of Cr in the stem and leaf, and Mn in the stem were significantly increased with time. These aforementioned findings support a well-founded metal-and-growth condition-specific application of poplars in phytoremediation processes, also triggering further in-depth assessments to enhance the efficiency of relevant poplar-based technologies. [ABSTRACT FROM AUTHOR]

Atmospheric deposition is an important source of the essential trace element selenium (Se) to terrestrial ecosystems and food chains. The fate of Se supplied to surface environments by atmospheric deposition strongly depends on total Se concentrations as well as its chemical form (speciation). However, the factors determining total Se and its speciation in atmospheric deposition remain poorly understood. Here, we applied different chemical measurements to aerosol samples taken at a weekly resolution over 5 years (2015–2019), as well as precipitation and cloud water samples taken during a field campaign of two months in 2019 at Pic du Midi Observatory (French Pyrenees; 2877 m a.s.l.) and combined these observations with sophisticated modelling approaches. The high-altitude site enables the investigation of local and long-range elemental transport from both marine and continental sources and the role of different weather systems in elemental deposition. Total concentrations of trace elements were measured in aerosol extracts and wet deposition, and Se speciation was obtained with an optimized chromatographic method coupled to inductively coupled plasma tandem mass spectrometry (LC-ICP-MS/MS). These analyses were combined with molecular organic compound analysis by pyrolysis-gas chromatography mass spectrometry (Py-GC-MS). For modelling the source contributions to Se, we used a combination of i) a Eulerian approach with the atmospheric aerosol-chemistry-climate model SOCOL-AERv2, and ii) a Lagrangian approach with air parcel backward trajectories and a moisture source diagnostics. While weekly Se measurements in the 2015–2020 aerosol time series agreed very well (r ~0.8) with SOCOL-AERv2 model results, the higher Se concentrations (>0.05 ng·m-3) observed in summer were underestimated by the model. We could explain these higher concentrations in summer by convection related to thunderstorms that led to high aerosol loadings and which are not resolved explicitly in the model. In addition, convective events, associated with continental moisture sources, also explained the highest concentrations of Se and most other trace elements in wet deposition, due to efficient below cloud scavenging, indicating the importance of local cloud dynamics on the supply of Se and other, essential and non-essential, trace elements to surface environments. While data for water isotopes in precipitation indicated an uncoupling of hydrological and trace element cycling related to below cloud scavenging, cloud water isotopes and trace elements showed high correlations indicating that the water and trace element cycles are strongly coupled from the source to the formation of clouds with a possible decoupling occurring during precipitation. Furthermore, cloud water showed more regional trace element and moisture sources than precipitation samples. With this comprehensive set of observations and model diagnostics we could explain inorganic Se speciation in unprecedented detail by linking moisture sources and organic chemical compounds in aerosols to speciation data of Se and S, indicating local vs long-range transport and anthropogenic vs natural Se sources. We report for the first-time organic Se in precipitation (and aerosols), for which we could elucidate a marine biogenic source. Our study thus provides new insights into the factors explaining atmospheric deposition of Se and other trace elements and highlights the importance of weather system dynamics in addition to source contributions for the atmospheric supply of trace elements to surface environments. [ABSTRACT FROM AUTHOR]

Activation of low-grade phosphate rocks such as dolomite phosphate rock (DPR) with organic molecules of humic acid (HA) and sodium lignosulfonate (SLS) holds promise for developing slow release P fertilizers. Consequently, activated DPR fertilizers also contains multiple essential plant elements, including P, Ca, Mg, Zn, and Fe, while minimizing leaching losses of nutrients and heavy metals. Greenhouse experiments were conducted to examine the availability of Ca, Mg, and trace metals in soils applied with activated DPR fertilizers and subsequent response of lettuce (Lactuca Sativa L.) as compared with original DPR and water-soluble P fertilizers including superphosphates (SP) and diammonium phosphates (DAP). Application of activated DPR fertilizers stimulated the uptake of Ca, Mg, Zn, Fe, B by lettuce plants relative to original DPR and DAP. Potential toxic elements such as Cr, Cd, Ni, Pb, and Cu were mostly immobilized in soil without uptake by lettuce when applied with activated DPRs primarily due to increased soil pH, as compared with water soluble fertilizers such as DAP and SPs. Apparently, the activated DPR fertilizers offer advantages over original DPR materials and water-soluble P fertilizers in providing multiple nutrients with minimal adverse effects on soil and environmental quality. [ABSTRACT FROM AUTHOR]

The Nanmushu Zn–Pb deposit is a large-scale and representative deposit in the Mayuan ore field on the northern margin of the Yangtze Block. This study investigates the trace element geochemistry of sphalerite from this deposit using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The results show that the main trace elements in sphalerite include various trace elements, such as Mn, Fe, Cu, Ga, Ge, Ag, Cd, Pb, Co, Hg, Tl, In, Sn, and Sb. Among them, Ag, Ge, Cd, and Cu are valuable components that may be recovered during mineral processing or smelting techniques. The histograms, LA-ICP-MS time-resolved depth profiles, and linear scan profiles indicated that most trace elements occur in sphalerite as isomorphs, while partial Pb, Fe, and Ag occur as tiny mineral inclusions. The correlation diagrams of trace elements revealed that Fe2+, Mn2+, Pb2+, and Tl3+ can substitute Zn2+ in sphalerite through isomorphism. In sphalerite, Cd2+ and Hg2+ together or Mn2+, Pb2+, and Tl3+ together can replace Zn2+, i.e., ((3Mn, 3Pb, 2Tl)6+, 3(Cd, Hg)2+) ↔ 3Zn2+. Moreover, there is a mechanism of Ge4+ with Cu+ or Ga3+ with Cu+ replacing Zn2+ in the Nanmushu deposit, i.e., Ge4+ + 2Cu+ ↔ 3Zn2+ or 2Ga3+ + 2Cu+ ↔ 4Zn2+. Furthermore, the trace element compositions indicate that the Nanmushu Zn mineralization occurred under low-temperature conditions (<200 °C) and should be classified as a Mississippi Valley-type (MVT) deposit. This study provides new insights into the occurrence and substitution mechanisms of trace elements in sphalerite and the metallogenic constraints of the Nanmushu deposit. [ABSTRACT FROM AUTHOR]