Copper Concentrations Research Articles

A novel major QTL underlying grain copper concentration in common wheat (Triticum aestivum L.)

Grain copper (Cu) concentrations represent a qualitative trait mainly controlled by genetic factors, which may differ between wheat varieties from the Sichuan Basin of China and other areas. However, the differences are poorly understood. Here, we investigated the grain Cu concentration in a remaining heterozygous line population derived from a multiparental recombinant inbred line. The grain Cu concentration varied from 4.25 to 13.44 mg/kg and 3.32 to 7.74 mg/kg over a two-year investigation, and the broad-sense heritability was 0.67. Bulked-segregation analysis revealed three quantitative trait loci on chromosomes 2A (QGr_Cu_Conc-2A), 2B (QGr_Cu_Conc-2B), and 4D (QGr_Cu_Conc-4D). QGr_Cu_Conc-2B is a novel locus, which was further narrowed between KASP-52.32 and KASP-56.57 with an interval of 52.32–56.57 Mb, explaining 17.10% of the phenotypic variation; its potential candidate gene was TraesCS2B03G0196500, encoding a chloroplast thylakoid lumen protein. KASP-52.32 successfully genotyped two common wheat populations, and the grain Cu concentration of CC genotype varieties was significantly higher than that of TT genotype varieties. Meanwhile, the concentrations of chlorophyll and the expression levels of three TaZIP8 and two TaZIP9 in flag leaves were higher in plants with high grain Cu concentration than in plants with low grain Cu concentration. These results provide guidance for understanding the genetic mechanisms underlying grain Cu concentration and may aid in wheat breeding.

Association Between Serum Essential Metal Elements and Blood Pressure in Children: A Cohort Study.

A limited number of cohort studies have explored the impact of serum essential metal elements on blood pressure (BP) or glycolipids and their regulatory mechanism in children. This study aimed to investigate the relationship between serum metal concentrations of iron (Fe), zinc (Zn), calcium (Ca), copper (Cu), and magnesium (Mg) and BP in children, and explore the potential mediating effects of glycolipid profiles. This cohort study included 1993 children (3566 BP measurements) aged 6-14 years in Chongqing, China. Serum essential metals, BP, lipid profiles, and glucose and insulin levels were measured. The relationship between serum metal levels and BP was analyzed using generalized linear and regression models, and a mediation analysis was performed to examine the potential mediating role of glycolipids. After adjusting for confounders, positive associations were found between serum Fe and Zn levels and BP parameters (all P < 0.05). A "U" style relationship between Cu and BP was found. Stronger associations were found in children aged ≤ 10years, with sex-specific differences for Fe, Zn, and Cu. The relationship between elevated BP and serum Mg and Ca was not found. Our study found that triglycerides showed a significant relationship with Fe and Zn levels (P < 0.005). Moreover, triglycerides, partially mediate the effects of Zn on elevated BP. Serum Fe, Zn, and Cu concentrations were associated with BP in children, and age and sex differences were observed. Triglycerides may play a mediating role. These findings highlight the importance of maintaining an optimal serum essential metal status for cardiovascular health in children and suggest potential early prevention strategies.

Cu- and Ag-mediated inactivation of L. pneumophila in bench- and pilot-scale drinking water systems.

Legionella pneumophila (Lp) is an opportunistic drinking water pathogen that can cause infections through the inhalation of Lp-containing aerosols and can occur in premise plumbing systems. In this work, the use of copper (Cu) and silver (Ag) ions was evaluated at the bench and pilot scale to determine (i) the effective independent concentrations of copper and silver that are efficacious in inactivating Lp, (ii) the impact of various water quality parameters on the efficaciousness of copper and silver ions, and (iii) the effectiveness and practicality of using dissociation to produce ions at the pilot scale. At the bench scale, it was determined that 0.3 ppm and 0.03 ppm of Cu and Ag, respectively, achieved 6-log inactivation of Lp in 5 h in experimental buffer. But, in dechlorinated filter-sterilized tap water, the same concentrations of Cu were not effective, and the effectiveness of Ag was slower. pH and dissolved inorganic carbon content were found to be important parameters in determining if the use of Cu and Ag ions is appropriate. At the pilot scale, dissociation was successfully used to produce Cu and Ag ions. Target levels of ions were met at the pilot scale but were difficult to achieve, and no impact was observed on Lp concentrations. Results from this study suggest that there are important caveats in the application of this technology when applied in a drinking water matrix and prior understanding of a system's water chemistry may be important to determine the effectiveness of Lp disinfection using Cu and Ag.IMPORTANCEThis work sheds light on the effectiveness of using Cu and Ag ions to inactivate (or kill) Legionella pneumophila. Legionella is an opportunistic drinking water pathogen of public health concern. This work demonstrates that there are important caveats in the application of using Cu and Ag ions to inactivate Legionella pneumophila.

Impact of a Complex Passivating Agent on Heavy Metal Immobilization in Pig Manure and Plant Development

In order to immobilize heavy metals in livestock and poultry manure and promote the safe utilization of pig manure resources, this experiment utilized three types of dried pig manure mixed with soil as raw materials. A combination of biochar and bentonite was established, including treatments with the addition of pig manure (CZ), 2.5% bentonite (F1), 7.5% bentonite (F2), 2.5% biochar (F3), 7.5% biochar (F4), 2.5% biochar + 2.5% bentonite (F5), 2.5% biochar + 7.5% bentonite (F6), 7.5% biochar + 2.5% bentonite (F7), 7.5% biochar + 7.5% bentonite (F8), and with zero addition (CK). After the passivation treatments had been applied, a soybean pot experiment was established to measure various physiological indicators at different soybean development stages. The results revealed that the passivated Cu was predominantly in the reduced and residual states. The passivation rates for F8 in LPS, F7 in MPS, and F8 in HPS were 34.10%, 29.90%, and 39.50%, respectively. Among the three concentrations of a pig manure–soil mixture, the impact of low copper concentration on soybean growth was relatively minimal, whereas medium and high copper concentrations significantly impaired soybean health, resulting in varying degrees of interveinal chlorosis and leaf yellowing from the tip to the base of young leaves, thereby affecting photosynthesis. The combined application of biochar and bentonite enhanced copper passivation and facilitated soybean growth and development.

Toward Global Sediment Management: Lessons Learned From a Multidimensional Risk Assessment

ABSTRACTSediment from the Serbian Great Bačka Canal (GBC), which has long been classified as toxic waste due to high pollutant concentrations, exemplifies the sediment management challenges in Europe, where regulations vary by country. Serbian legislation primarily focuses on total metal concentrations relative to prescribed limits. Our study addresses this limitation by using an integrated approach to assess sediment pollution's detrimental effects at the ecosystem level. This approach is particularly relevant for the GBC, an environmental hotspot historically impacted by severe pollution from untreated industrial wastewater and population growth. Although previous research on the GBC has predominantly focused on chemical analyses, often overlooking broader environmental and health impacts, our study aims to evaluate whether ecotoxicological tests provide a more comprehensive assessment of sediment quality compared to traditional methods. Although only copper concentrations surpassed national limits, multiple metals and polycyclic aromatic hydrocarbons (PAHs) exceeded international sediment quality guidelines (SQGs). Sequential extraction revealed that 50% of copper was immobilized in the residual fraction, and ecotoxicological tests with Myriophyllum aquaticum indicated potential toxicity. Human health risk assessments showed a low risk of carcinogenic effects from PAHs, but a higher risk associated with zinc and copper. These findings highlight the urgent need for pollution reduction and ecological restoration in the GBC and similar river systems.

SERIAL HEALTH ASSESSMENT WITH STANDARDIZED EXTERNAL SCORING AND HEMOLYMPH EVALUATION IN THE AMERICAN HORSESHOE CRAB (LIMULUS POLYPHEMUS).

Serial health assessment of a managed population of American horseshoe crabs (HSC; Limulus polyphemus) was performed. Twenty HSC were examined once a month for 7 mon; this included a physical exam with a standardized scoring sheet, HR, morphometrics, and hemolymph evaluation with hemocyte count, copper concentration, and biochemistry panel. The HSC in this population had varying levels of external lesions at enrollment. All HSC were clinically and behaviorally stable over the study period, with no apparent differences in evaluated parameters in relation to degree of external lesions. Although the standardized scoring sheet was found to be helpful to complete the evaluation, the qualitative criteria potentially masks clinically important gradations in some parameters. HR ranged from 4 to 60 bpm, with high intra- and interindividual variability. Increased prosomal widths (PW) were found to be correlated with lower HR. Plots of weight (W) in grams divided by PW in centimeters are roughly linear, and W:PW shows promise as a method of body condition evaluation in a hard-shelled animal. Serial collection of ∼2 ml of hemolymph led to no appreciable clinical decline in any animal. Total protein levels were stable and higher than previously reported for HSC in managed care. Glucose values were stable throughout the study period, which is interpreted as reflecting adequate nutritional intake in the study animals. Further studies are needed to determine the clinical utility of standardized vertebrate biochemistry panels in invertebrate species.

PROXIMATE, MINERAL AND PHYTOCHEMICAL ANALYSIS OF SOME MEDICINAL PLANTS COLLECTED FROM ORATHUR VILLAGE, THIRUPORUR TALUK KANCHEEPURAM DISTRICT TAMILNADU, INDIA

The use of medicinal plants has a long tradition as part of the human diet and has therapeutic agents. That is why they are well accepted by consumers and are generally considered to be environmentally friendly, efficient and generally considered to be safe alternative to antibiotics due to the presence of phytochemicals found in the leaves, stem bark, roots, flowers amongst others. Medicinal plant also possesses nutritional properties and play multiple pharmacological roles such as anti-inflammatory, antioxidant, anti-cancer, antimicrobial, anti-viral, anti-fungal, anti-helminthic, hepato-protective activity amongst others. This study was aimed at accessing the proximate, mineral and phytochemical composition of Tephrosia purpurea, Adhatoda vasica, Crataeva nurvala, Bauhinia racemose, Holarrhena antidysenterica and Aegle marmelos. Result on proximate analysis showed that moisture content varied from 13.57 – 16.02 %, dry matter (83.98 – 86.43 %), crude protein (5.06 – 7.12 %), ash (9.90 – 12.04 %), crude fibre (12.74 – 14.32 %), crude fat (0.10 – 0.22 %) and carbohydrates (40.30 – 50.17 %). Concentrations of calcium, phosphorus, potassium, magnesium, zinc, manganese, sodium and copper ranged from 120 – 148.0 mg/100g, 180.0 – 300 mg/100g, 66.8 – 94.2 mg/100g, 41.8 – 69.8 mg/100g, 27.9 – 44.6 mg/100g, 119 – 133 mg/100g and 8.21 – 13.1 mg/100g respectively. Quantitative evaluation of tannins showed that values varied from 39.00 – 46.50 mg/g, alkaloids (26.35 – 35.09 mg/g), saponins (20.05 – 30.40 mg/g), flavonoids (66.10 – 86.11 mg/g), terpenoids (40.71 – 45.88 mg/g) and phenols (106.8 – 125.4 mg/g). In conclusion, it was discovered that it contained some essential nutrients in significant quantities. However, values obtained varied due to age of plant, specie, processing method among others. The presence of phytochemicals in these plant suggests that it has pharmacological properties. Accessing the constituent’s in this plants could lead to a novel drug discovery and curb the increasing cases in antimicrobial resistance.

Mechanism study of the effect of copper ions on the stability of As(III) sulfuration precipitation in acidic copper smelting wastewater.

Sulfide precipitation is considered as a very efficient method for removing arsenic from actual copper smelting acidic wastewater. However, the arsenic removal process can be affected by copper ions. This study focuses on the mechanism of copper ions' influence on the stability of As(III) sulfuration precipitation. Sulfuration reaction experiments are carried out using Na2S in three different simulated highly acidic wastewaters with initial As(III) concentrations of 2000mg/L (LAs), 5000mg/L (MAs), and 10000mg/L (HAs), and the implications of processes variables of S/As ratio and copper concentration on the stability of As(III) sulfuration precipitation are discussed. The results show that the As(III) sulfuration precipitation is significantly affected by copper ions in the LAs reaction systems, whereas in the MAs and HAs reaction systems, which can be noticeably affected by copper ions only when the S/As is not greater than 1.5 (≤ 1.5), i.e., when the amount of Na2S is insufficient. Person correlation analysis also demonstrates a remarkable negative correlation (correlation coefficient is around - 0.96) between the S/As ratio and copper ion concentration on As(III) removal efficiency in the LAs reaction systems. The effect of copper ions on As2S3 is further investigated, and it is detected that copper ions cause approximately 3.3% of the precipitated As2S3 to be re-dissolved. This study proves that copper ions not only compete with As(III) for S2-, but also cause the precipitated As2S3 to re-dissolve. Therefore, in the actual manufacturing process, it is essential to control not only the sulfiding dose, but also the copper ions. This study provides a specific reference for actual enterprises to sulfurize As(III) from highly acidic wastewater and is of great significance for controlling actual industrial processes.

Effect of annealing temperature onto physical properties of Cu doped ZnO thin films prepared using spray pyrolysis

Abstract Herein we report the effect of annealing on spray-pyrolysis-deposited Cu-doped zinc oxide thin films, with a fixed 3 wt% copper concentration and annealing temperatures of 450 and 500 °C. Various analytical techniques were employed to evaluate the effect of annealed films, which exhibited high stability in physical properties and minimal influence from the annealing process. XRD analysis confirmed that all films maintained a hexagonal ZnO structure without any additional phases, indicating the high purity of the films, with the (002) peak serving as the main diffraction peak for both as-deposited and annealed films. Crystallite size, calculated using the Halder-Wagner equation, revealing an increase from 13.96 nm for the as-deposited film to 14.26 nm for film annealed at 450 °C and 14.65 nm for film annealed at 500 °C. Microstrain values were measured at 2.3 × 10−3, 2.5 × 10−3, and 1.3 × 10−3 for the as-deposited and annealed films. Surface imaging with FE-SEM revealed average grain sizes of 57.25 nm, 68 nm, and 67.8 nm for the as-deposited film and those annealed at 450 °C and 500 °C, respectively. The estimated band gap values were 3.14 eV for the as-deposited films, 3.15 eV for those annealed at 450 °C, and 3.16 eV for films annealed at 500 °C. According to the Spitzer-Fan model, both the density of states and plasma frequency remained constant across the films, while the relaxation time and optical mobility were lowest at 450 °C, where the high-frequency dielectric constant reaches its peak.

Heavy metal characteristics and ecological threat assessment in water and sediments of Eniong Creek, Niger Delta, Nigeria

Heavy metal characteristics and ecological threat assessment in water and sediments of Eniong Creek, Nigeria was studied between August 2022 and January 2023 in 3 stations. Seven heavy metals were analyzed with standard methods and compared with quality Standard. Ecological threat was assessed in water using two metal pollution indices while six sediment quality assessment indices were used to access the sediment quality. Results showed that the mean concentrations of nickel, copper, cadmium and zinc in water sample exceeded the permissible limits set by National environmental (surface and groundwater) quality regulations for aquatic life, while copper and cadmium exceeded the permissible limits set by Canadian sediment standards quality for the protection of aquatic life in sediments in all the stations. The heavy metal pollution index (HPI) values exceeded the threshold (100) across the stations, ranging between 469.53 and 686.74 while comprehensive pollution index (CPI) ranged between 1.405 and 1.854, indicating moderate contaminated water. The sediment indices indicated that cadmium and copper were the major metallic pollutants. The indices indicated the following –contamination factor: copper (moderate) and cadmium (very high), degree of contamination (very high); ecological risk: cadmium and copper (high) while lead and zinc were moderate; potential ecological risk (high); quantification of contamination: cadmium and copper (anthropogenic); geo-accumulation index: cadmium (very highly polluted). The study revealed that the water body and sediments were polluted, attributed to anthropogenic activities.Keywords: Eniong Creek; Heavy Metals, Nigeria; Sediment; Water

A Preliminary Health Risk Assessment of Heavy Metal Contamination in Chembarambakkam Lake, Tamil Nadu, South India

Chembarambakkam Lake, an important freshwater reservoir in Chennai that provides drinking water to the city, has noticed a decline in water quality as a result of heavy metal pollution. This study aimed to evaluate the heavy metal contamination in the environment of Chembarambakkam Lake with a health risk assessment. This study involved a comprehensive analysis of toxic heavy metal levels in five waters, sediments, and commercially available freshwater fish samples, considering their bioaccumulation and potential risks to human health. We observed lead (Pb), cadmium (Cd), zinc (Zn), and copper (Cu) concentrations in water, sediments, and various fish species, including tilapia (Mozambique Tilapia), wild carp (Hemiculter leucisulus), pearl-spot (Etroplus maculatus), spotted barb (Barbodes binotatus), and snakehead murrel (Channa Striate). The results indicated that, in order of prominence, the metals in the water were Cu &gt; Zn &gt; Pb &gt; Cd, whereas those found in sediments were Zn &gt; Cu &gt; Pb &gt; Cd. The metal concentration in the sediments varied between Cd (0.52–0.82 µg/g), Cu (13.75–38.07 µg/g), Pb (1.30–3.74 µg/g), and Zn (12.60–61.12 µg/g). Similarly, the metal concentrations in the water varied between Cd (0.63–0.72 µg/L), Cu (5.35–55.17 µg/L), Pb (BDL–12.39 µg/L), and Zn (0.62–1.49 µg/L). The order of metals in the fish was Zn &gt; Cd &gt; Cu &gt; Pb. The Cd concentration ranged from 0.3 to 0.60 µg/g, Cu was from BDL to 0.72 µg/g, Pb was from BDL–0.68 µg/g, and Zn was from 13.32–48.48 µg/g. The Cd and Zn concentrations were consistently the highest across the fish, sediment, and water samples. These findings shed light on the health risks associated with heavy metal pollution in Chembarambakkam Lake and suggest the need for potential bioremediation approaches.

Kinetic adsorption and isotherm models of nickel

The study investigated the adsorption capacity of Pinus halepensis Mill biomass (PHM) that has been modified to remove nickel (II) from aqueous solutions. The underwent chemical modification using zinc chloride (0.1N) to produce activated carbon. The resultant products were analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. Several variables were taken into account to achieve optimal adsorption conditions. These factors include the duration of agitation, the starting concentration of copper, and the pH level. Consequently, the highest level of efficiency was obtained at 90 mg/g when equilibrium was established after 120 minutes. The pseudo-second-order kinetic model offers a more appropriate characterization of the adsorption kinetics. Nickel adsorption adheres to the principles of the Langmuir and Freundlich isotherms. The Langmuir isotherm model produces the most favorable parameters. The adsorption capacity increased with the elevation of the initial concentration (from 1000 to 400mg/l) employed in this work at a neutral pH and 25°C in temperature.

Hazard Study of Sludge from Mining Wastewater Treatment Systems (Tailings), Accumulation of Contaminants and Potential Utilization Proposals

The increase in gold mining activities has led to a substantial rise in tailings generation, which carry distinct physicochemical and microbiological properties. This study aimed to evaluate the hazardous characteristics of mining tailings using the CRETIB (corrosivity, reactivity, explosiveness, toxicity, ignitability, biological-infectious) methodology. The research analyzed concentrations of heavy metals including arsenic, cadmium, copper, chromium, lead, mercury, nickel, and zinc, alongside parameters such as pH, cyanide, hydrogen sulfide, and coliform bacteria. Tailings samples were collected from a mine in Ponce Enriquez, Ecuador, at the surface and at a depth of 2 m across three monitoring campaigns. The results indicate that the tailings do not exhibit hazardous characteristics according to CRETIB criteria. While arsenic, chromium, copper, nickel, zinc, and mercury concentrations showed significant differences between the surface and 2 m depth, accumulating at the bottom of the tailings dam by 30–72%, parameters such as pH, cyanide, and hydrogen sulfide were higher at the surface, likely due to volatilization and precipitation effects. Lead did not show significant differences, but also tended to accumulate at depth. These findings suggest that the tailings could be safely utilized in the production of construction materials such as bricks, geopolymer concrete, and fiber cement, promoting circular economy practices and sustainable development in mining.

Experimental study on metallic impurity behavior with boronization wall conditioning in EAST tokamak

Operation of EAST tokamak with full metal wall without any wall conditioning are attempted in 2023 and 2024 experimental campaign to address the issues related to ITER tungsten wall operation. It is found that H-mode plasma could be sustained even with a substantial increase in metallic impurity content caused by strong plasma-wall interaction under uncoated metal wall. Boronization wall conditioning is therefore performed to improve the plasma performance with higher injected power. This study aims to quantitatively assess the impact of boronization wall conditioning on metallic impurity concentration and behavior in the EAST tokamak. It is then proved to be an effective wall conditioning approach for significantly controlling high-Z impurity content. In this work, the impurity spectra at extreme ultraviolet (EUV) wavelength range measured by sets of fast-time-response and space-resolved EUV spectrometers are widely used in the data analysis. The variation in the boron content in plasma after boronization are investigated by monitoring the 2nd order of B V line at 48.59 Å. It is found that the persistence time of boron in EAST device after a boronization with 10 g of carborane (C2B10H12) is about 2000 s (∼150 shots) of discharge duration. The impact of different wall conditions (uncoated metal wall and boron coated wall) on metallic impurity content are then quantitatively studied. After boronization, the concentration of tungsten (CW) and molybdenum (CMo) dropped by 85 %, e. g., from 2.0 × 10-4 to 4.1 × 10-5 and from 4.6 × 10-5 to 6.3 × 10-6, respectively. While the concentration of copper (CCu) and iron (CFe) decreased by approximately 50 % and 65 %, respectively, e. g., from 4.3 × 10-5 to 2.1 × 10-5 and from 2.0 × 10-4 to 6.9 × 10-5. A comparison of the line emission profiles from tungsten ions of W26+ − W32+ and W43+ before and after boronization reveals an overall reduction in the intensity while without obvious change in the profile shape, which suggests a reduction in metallic impurities source after boronization instead of altering impurity transport in core plasma significantly.

Interactive effect of anthropogenic activities and seasonal changes on the biophysicochemical properties and heavy metal status of tropical surface water resources

Seasonal changes and uncontrolled anthropogenic activities alter surface water resources quality and threaten access to water for consumptive and non-consumptive needs of humankind. This study examines the interactive impact of seasonal variation and anthropogenic activities on selected biophysicochemical properties and heavy metal status of tropical surface water resources. The study was conducted with water samples taken from upstream, midstream and downstream of the networked surface water system of the Barekese and Owabi dams in the Ashanti Region of Ghana during the wet season (March – Mid. October 2019) and dry season (Mid. October – February,2019). The result revealed that the downstream had significantly higher levels of conductivity, BOD, NO3-N, NH4-N, as well as Escherichia coli (E. coli) when compared to the midstream and upstream. The levels of NO3-N were significantly higher during the wet season while conductivity, TSS, E. coli and copper were higher during the dry season. Significant interactive effects between seasons and anthropogenic activities on water quality were observed. The anthropogenic impacts on conductivity, E. coli, and copper concentration were observed during the dry season while that of NO3-N was observed during the wet season. Overall, the water quality was poorest during the dry season and mainly in the downstream where anthropogenic activities are pronounced. This means that efforts towards improving surface water quality should be targeted at downstream activities, especially during the dry season. The study recommends the need for effective monitoring and control of activities such as dry season farming and indiscriminate discharge of waste into tributaries of surface water especially within the downstream.

Using δ65Cu and δ34S to determine the fate of copper in stream waters draining porphyry mineralization: Implications for exploration targeting

The fate of metals, such as Cu, in stream waters draining porphyry mineralization is commonly controlled by several natural processes such as sorption, microbial processes, and ligand availability. Isotopes of Cu offer a novel approach to understanding these processes and determining metal sources within complicated mineralogical systems. Drainages at the Casino Cu-Au-Mo porphyry deposit, Yukon, Canada exhibit circumneutral (pH > 5) in Casino Creek and natural acid rock drainage (pH < 3.5) in Proctor Gulch with the precipitation of schwertmannite (Fe3+). Isotopic systems δ65Cu and δ34Ssulfate indicate different metal sources, with signatures of both hypogene and supergene mineralization. Waters from Proctor Gulch contain δ65Cu values (< −0.5 ‰) consistent with supergene Cu sources from the leached or oxide portion of the mineralization. Comparatively, drainage in the upper part of Casino Creek contains a δ65Cu composition (> 0.5 ‰) characteristic of Cu sourced from hypogene sulfide mineral oxidation. Variation in metal sources is similarly supported by aqueous δ34Ssulfate values in the stream waters, which suggest mixing of S derived from a sulfide mineral phase and a much heavier sulfate mineral (e.g., gypsum or anhydrite). Isotopic fractionation of Cu in the dissolved (<0.45 μm) phase presents two predominant controls on Cu dispersion. The natural acid conditions in Proctor Gulch favor the preferential co-precipitation of 63Cu with schwertmannite but could be influenced by intracellular assimilation or adsorption by microbes, which also has been shown to preferentially favor 63Cu. Copper isotopic fractionation results in a gradient of increasing δ65Cu values in waters downstream. In Casino Creek, higher pH conditions favor the precipitation of Fe(OH)3 and the preferential adsorption of 65Cu, resulting in decreasing δ65Cu values downstream. Copper concentrations in stream waters remain elevated (up to 4.1 μg/L) above ambient background (1.9 μg/L) levels up to 11 km downstream of the deposit. Given the abundance of surface water in many parts of northern Canada, hydrogeochemical prospecting using broad scale stream water catchment analysis is clearly a viable greenfield exploration methodology.

Формирование техногенных гидрохимических потоков при разработке месторождений олова в арктических районах Якутии

The article analyzes the results of studying technogenic hydrochemical dispersion flows arising during the development of ore and placer tin deposits in the Arctic regions of the North-East of Yakutia. Most of the large tin deposits are located beyond the Arctic Circle: primary (Deputatskoye, Dyakhtardakhskoye, Kester, Ulakhan-Egelyakhskoye, Churpunnya, Ege-Khaya) and placer (Smolnikova, Tasappa, Tirekhtyakh, Chokurdakhskaya) deposits. Development of tin deposits leads to a sharp change in the chemical composition of natural waters and the formation of extensive technogenic hydrochemical flows that negatively affect ecosystems. Pollution of natural waters during the development of tin deposits is associated with abnormal concentrations of mineral suspensions, sulfates, hydrogen, iron, aluminum, manganese, copper, zinc, lead, arsenic, and mercury.

Efficient removal of low concentrations of copper and lead ions in water using chitosan-condensed tannin composite microspheres

Condensed tannin was solidified onto chitosan microspheres to prepare chitosan-tannin (CT) composite microspheres with a simple preparation method to study its performance in adsorbing copper (Cu2+) and lead ions (Pb2+) in aqueous media. The study investigated the influence of the mass ratio of tannin and chitosan, pH value, adsorption time, and initial concentrations of Cu2+ and Pb2+ on the adsorption capacity of Cu2+ and Pb2+ ions. Additionally, the study examined the adsorption isotherms and kinetics of Cu2+ and Pb2+ on CT composite microspheres. The adsorption process aligns more closely with the fitting results of the Langmuir model. The maximum capacity for saturated monolayer adsorption of CT composite microspheres for Cu2+ and Pb2+ was 37.6 and 52.9 mg/g, respectively. The adsorption process of CT composite microspheres for Cu2+ and Pb2+ was primarily driven by single-layer chemical adsorption. In addition, metal ions adsorbed onto CT composite microspheres can be released by treating them with a dilute solution of strong acid. Furthermore, the CT composite microspheres exhibited impressive removal efficiencies of 82 % and 95 % for Cu2+ and Pb2+ respectively, even at low concentrations of 2 mg/L. The CT composite microspheres have the ability to easily separate the adsorbed Cu2+ and Pb2+ ions.

Physico-chemical and heavy metal analysis of ground and surface water obtained from some selected areas in Kaduna metropolis

Water samples from 10 selected boreholes and 3 hand-dug wells within the three areas of Kaduna Metropolis were collected; Physico-Chemical parameters and heavy metals were determined. The results of the Physico-Chemical analysis were obtained in the following range, temperature (17.3-20.9), conductivity (44-60 mV), alkalinity (184-688 mg/l) BOD (6.5-15.4 mg/l) all within the set limit of WHO standard, TDS value (1197-2340 mg/l) fell above the set limit of WHO standard , the chemical constituents were obtained in the following range pH (7.25-7.67), Magnesium (1.28-6.08 mg/l), Calcium (0.12-0.90 mg/l), Nitrate (0.03-0.32 mg/l) with Chloride value (2.33-495.6) above the set limit of WHO standard, the highest value of 0.1241mg/l was found in Chromium. the concentrations of heavy metals (mg/l) Chromium, Iron, Lead, and Copper in the Groundwater were found in the following range, lead (0.0001- 0.120 mg/l), Chromium (0.0001- 0.124 mg/l), iron (0.0191- 0.3547 mg/l) and Copper (0.0006- 0.0070 mg/l). The results obtained fell within the limit set by World Health Organisation with the exception of Chromium which was 0.124 mg/l in sample SH3 and Lead which was in sample MF2. Which these two had concentrations above the limits set by World Health Organisation.

Optimization and greenness assessments of the supramolecular solvent-assisted cloud point extraction method for copper spectrophotometric determination in water and food samples

For the first time, the green supramolecular solvents (SUPRASs)-based cloud point extraction (CPE) approach was created for copper spectrophotometric determination in food and water samples. SUPRASs were synthesized in six different forms and used as synergistic reagents. SUPRAS (water, salicylic acid, and THF) mixed with TritonX-114 (TX-114) to be the most efficient extraction solvent. The validation investigation found that the linearity range, limit of detection (LOD), limit of quantification (LOQ), enhancement factor (EF), and preconcentration factor (PF) are 0.2-700.0 μg L-1, 0.1 μg L-1, 0.33 μg L-1, 85.0, and 50.0, respectively. The technique's accuracy was calculated using standard reference materials (SRMs) (GBW07605 Tea Leaves and GBW10019 Apple) and ranged between 96.0 and 98.9%. Lastly, a novel SUPRAS-CPE approach was utilized to determine copper concentrations in real water, food tests, and SRMs. Furthermore, the SUPRAS-CPE conforms to green chemistry principles by using less both time and energy than previous studies. Also, the greenness values were determined by three recent tools. The Analytical Greenness Metric for Sample Preparation (AGREEprep), Complex Modified GAPI (ComplexMoGAPI), and Sample Preparation Metric of Sustainability (SPMS) programs produced results of 0.79, 86.0, and 8.42, respectively. These results are strongly aligned with both green ideals and environmentally friendly practices. The finding increases the possibilities for using SUPRAS-CPE to extract additional mineral ions.