Concentrations Of Metal Elements Research Articles

The effect of various urea-in-water solution types on exhaust particle number emission.

In order to qualitatively evaluate the impact of urea-in-water solution on the particle number emission, five different urea types were chosen under diesel engine bench test. The results show that compared to the instantaneous particle concentrations without injection, the instantaneous particle concentrations with injection increase distinctly, which are larger around 0.3-1.2 times than that without urea-in-water solution. At high speed phase, the instantaneous particle concentrations with urea-in-water solution injection rise obviously, especially for C and E solutions. In addition, the particle size distribution characteristic does not change with the urea-in-water solution dosing. The PN emission factors follow the sequence of C solution > E solution > A solution > B solution > D solution. It is deduced that the metallic element contents in the urea-in-water solution play a key role for the PN emission factor. In the future, the particle formation due to urea-in-water solution injection should be given more attention.

Analysis of heavy metal, rare, precious, and metallic element content in bottom ash from municipal solid waste incineration in Tehran based on particle size

Waste incineration is increasingly used worldwide for better municipal solid waste management and energy recovery. However, residues resulting from waste incineration, such as Bottom Ash (BA) and Fly Ash (FA), can pose environmental and human health risks due to their physicochemical properties if not managed appropriately. On the other hand, with proper utilization, these residues can be turned into valuable Municipal metal mines. In this study, BA was granulated in various size ranges (< 0.075 mm, 0.075–0.125 mm, 0.125–0.5 mm, 0.5–1 mm, 1–2 mm, 2–4 mm, 4–16 mm, and > 16 mm). The physicochemical properties, heavy metal elements, environmental hazards, and other rare and precious metal elements in each Granulated Bottom Ash (GBA) group from Tehran's waste incineration were examined using ICP-MASS. Additionally, each GBA group's mineralogical properties and elemental composition were determined using X-ray fluorescence (XRF) and X-ray diffraction (XRD). The results showed that the average concentration of heavy metals in GBA, including Zn (1974 mg/kg), Cu, and Ba (790 mg/kg), Pb (145 mg/kg), Cr (106 mg/kg), Ni (25 mg/kg), Sn (24 mg/kg), V (25 mg/kg), As (11 mg/kg), and Sb (29 mg/kg), was higher in particles smaller than 4 mm. Precious metals such as gold (average 0.3 mg/kg) and silver (average 11 mg/kg) were significantly higher in GBA particles smaller than 0.5 mm, making their extraction economically feasible. Moreover, rare metals such as Ce, Nd, La, and Y were detected in GBA, with average concentrations of 24, 8, 11, and 7 mg/kg, respectively. The results of this study indicated that BA contains environmentally concerning metals, as well as rare and precious metals, with high concentrations, especially in particles smaller than 4 mm. This highlights the need for proper pre-treatment before using these materials in civil and municipal applications or even landfilling.

Influence of leachate microenvironment on the occurrence of phthalate esters in landfills

Phthalate esters (PAEs) are added to various products as plasticizers. Plastic waste containing PAEs enters landfills as they age with use. However, the influence of microenvironmental changes on the occurrence of PAEs during landfill stabilization is still unknown. In this study, we evaluated the relationship between the physical and chemical properties of leachate, the structure of bacterial communities and the chemical structure of dissolved organic matter (DOM), and the occurrence of PAEs and the mechanism underlying their responses to changes. Landfill leachate in different stabilization states had high Cl− and NH4+ contents and its metal element (Cr, Pb, and Zn) contents generally decreased with the increase in landfill ages. Proteobacteria, Bacteroidetes, and Firmicutes were important phyla and had an average relative abundance of 68.63%. The lignin/carboxylate-rich alicyclic molecule structure was the main component of DOM (56%–64%). Of the 6-priority controlled PAEs in leachate, di-n-butyl phthalate was the most abundant (1046 μg L−1), while butyl phthalate was not detected. The results showed that pH, the relative abundance of Chloroflexi, and the value of SUVA254 can directly influence the occurrence of PAEs in leachate. The positive and negative effects vary depending on the PAE content and molecular weight. DBP and DEHP have higher environmental risks in the aquatic system. These results are intended to provide a scientific basis for the evolutionary characterization of the microenvironment in complex environmental systems and the control of novel contaminants, such as PAEs.

Metallic trace elements in marine sponges living in a semi-enclosed tropical lagoon.

The ability of marine filter feeders to accumulate metals could help monitor the health of the marine environment. This study examined the concentration of metallic trace elements (MTE) in two marine sponges, Rhabdastrella globostellata and Hyrtios erectus, from three sampling zones of the semi-enclosed Bouraké Lagoon (New Caledonia, South West Pacific). MTE in sponge tissues, seawater, and surrounding sediments was measured using inductively coupled plasma with optical emission spectroscopy. The variability in sponge MTE concentrations between species and sampling zones was visually discriminated using a principal component analysis (PCA). Sponges showed Fe, Mn, Cr, Ni, and Zn concentrations 2 to 10 times higher than in the surrounding sediments and seawater. Hyrtios erectus accumulated 3 to 20 times more MTE than R. globostellata, except for Zn. Average bioconcentration factors in sponge tissues were (in decreasing order) Zn > Ni > Mn > Fe > Cr relate to sediments and Fe > Ni > Mn > Cr > Zn relate to seawater. The PCA confirmed higher MTE concentrations in H. erectus compared to R. globostellata. Our results confirm that marine sponges can accumulate MTE to some extent and could be used as a tool for assessing metals contamination in lagoon ecosystems, particularly in New Caledonia, where 40% of the lagoon is classified as a UNESCO World Heritage Site.

Phenotypic and genetic dissection of the contents of important metallic elements in hybrid rice grown in cadmium-contaminated paddy fields

Rice (Oryza sativa L.) is a staple food that feeds over half of the world's population, and the contents of metallic elements in rice grain play important roles in human nutrition. In this study, the contents of important metallic elements were determined by ICP-OES, and included cadmium (Cd), zinc (Zn), manganese (Mn), copper (Cu), iron (Fe), nickel (Ni), calcium (Ca), and magnesium (Mg) in brown rice, in the first node from the top (Node 1), in the second node from the top (Node 2), and in roots of 55 hybrids and their parental lines. The heritability of metallic element contents (MECs), the general combining ability (GCA) for MEC, and the correlation between MECs in different organs/tissues of hybrids were also analyzed. The results indicated that: (1) there was a positive correlation between the contents of Cd and Zn in nodes and roots, but a negative correlation between the contents of Cd and Zn in brown rice of the hybrids(2) the GCA for MECs can be used to evaluate the ability of the parental lines to improve the metal contents in brown rice of the hybrids(3) the contents of Cd, Zn, Ca, and Mg in brown rice were mainly affected by additive genetic effects(4) the restorer lines R2292 and R2265 can be used to cultivate hybrids with high Zn and low Cd contents in the brown rice.

Distributions of Chromium, Copper, and Cadmium in the estuary-coastal surface sediment of Tin-Rich Island

Belitung Island known as one of the tin producer in the world, as it lied in the South East Asian tin belt. The study was conducted in the North Belitung Island to investigate some metal elements concentration of sediment along the estuary river and coastal area near to carbonate reef environment system. Thirteen sediment samples were collected from estuarine riverbed, shoreline, and offshore of North Belitung. The concentrations of metal elements were analysed to assess the environmental pollution characteristics by using flame AAS (Atomic Absorption Spectrophotometry) method. The result indicated that the average concentrations of chromium (Cr), copper (Cu), and cadmium (Cd) were 1.62-18.26, 5.72-80.07, and 1.4-4.59 mg/kg dry weight, respectively. The calculation of geo-accumulation index (Igeo) was adopted in this study to evaluate the heavy metal pollution. The Igeo values revealed that this research area has been moderately polluted by Cr and Cu, and unpolluted-moderately polluted by Cd. Based on the contamination level to adverse biological effect, the heavy metals concentration in this research area has the low potential to adverse biological effect by Cr and Cu, and low-moderately potential by Cd. This information is important to lead the study about any other elements and heavy metals to evaluate the risk assessment in the tropical area.

Developing sediment provenance discrimination tracers using major elements in East China Sea mud deposits

Discriminating shelf sediment provenances using sediment trace metal and rare earth element (REE) concentration and isotope ratios and clay mineral contents has several unavoidable hurdles, such as the effect of sediment grain size on metal concentrations, ubiquitous inclusion of REE-rich heavy minerals in sediments, and meager and inconsistent compositional differences. Furthermore, to date, no study has analyzed and determined a convincing tracer that can differentiate between Huanghe (HH) and Changjiang (CJ) sediment provenances, especially quantitatively. In this study, we quantitatively discriminated the provenances of the southwestern Cheju Island mud deposit (SWCIM) in the northern East China Sea (ECS) shelf, using seven major elements (Si, Al, Fe, K, Na, Ca, and Mg), and further determined the spatial variations of the contributions from the HH and CJ rivers to the northern ECS sediments. The results indicate that the SiO2/Al2O3 and Fe2O3/Al2O3 ratios of the HH, CJ, and Korean (KR) river sediments can be considered as reliable tracers for differentiation of the northern ECS shelf sediment provenance. Furthermore, the quantitative contributions of HH, CJ, and KR to the northern ECS sediment budget were approximately 80, 20, and 0%, respectively. The systematic spatial variations of the HH and CJ river contributions to the sediment provenances in the study area, such as the significant contributions of the HH river in the northwestern part of the SWCIM and the CJ river in the southwestern part, support the availability and applicability of the Fe2O3/Al2O3 ratio as a sediment provenance discrimination tracer. We propose that these major element concentration ratios can be applied to distinguish other siliciclastic shelf sediment provenances.

Prenatal Metals Exposure and pre-adolescents’ Emotional and Behavioral Problems

Emotional and behavioral problems during childhood raise the risk of subsequent developmental of mental disorders. Our aim was to study the association between maternal metal and trace element concentrations during gestation and these problems in 9 year-old children. The study sample comprised Spanish mother-child pairs in the INMA project (n = 1003). Metals and trace elements (As, Cd, Co, Cu, Mo, Ni, Pb, Sb, Se, Tl and Zn) were measured in urine samples collected during pregnancy. Inorganic As metabolites were speciated in a subsample (n = 729). Emotional and behavioral problems were assessed using the Child Behavior Checklist (CBCL) composed of three scales: internalizing, externalizing and total problems. Sociodemographic, dietary and exposure to other environmental pollutants were obtained through questionnaires. Single nucleotide polymorphisms in brain- and metabolism-related genes APOE, BDNF, GSTP1, and PON1 were determined in cord blood. Multivariate negative binomial models were used. The interaction with sex and genotypes was evaluated including interaction terms. A multi-element analysis was carried out by a principal component analysis. Higher concentrations of Cu, monomethylarsonic acid, and Pb during pregnancy were associated with an increased incidence ratio risk (IRR) between 4.6 and 7.5% for internalizing and externalizing problems for all three CBCL scales in the children. Increasing Mo, Ni and Co concentrations were associated with higher IRR for internalizing problems (up to 8%), and Cd for externalizing problems (6.7%). Modifications by sex and genotypes were found for several associations. Multi-element analysis associated multiple metals and trace elements (Ni, Cu, Se, Cd and Pb) with higher internalizing problems.

The Relationship between Body Mass Index, Metal Elements, and Antioxidant Capacity of Semen on The Human Sperm Chromatin.

Sperm chromatin abnormalities are defects in nuclear maturation and DNA integrity. These defects originated from defective spermatogenesis due to a lack of DNA repair during chromatin remodeling. Changes in semen elements can cause damage to chromatin. There is little information about the relationship between changes in trace metal elements and total antioxidant capacity (TAC) with sperm chromatin damage. The present study was conducted to determine the relationship between Selenium (Se), Iron (Fe), Zinc (Zn), Copper (Cu) and the TAC of semen with the status of human sperm chromatin. In this experimental study, semen samples (n=30) were collected from healthy men referred to Kermanshah Motazadi Hospital and stored in liquid nitrogen; after thawing and centrifugation, sperm were separated. The atomic absorption method was used to measure the concentration of metal elements. The TAC was evaluated using the ferric-reducing antioxidant capacity of the plasma method. Furthermore, the integrity of sperm chromatin was measured using the sperm DNA fragmentation (SDF) method. The status of sperm chromatin had a non-significant correlation with body mass index (BMI, P=0.25, r=0.21) and a non-significant negative correlation with sperm count (P=0.71, r=-0.71) and motility (P=0.75, r=0.61). In addition, there was no significant relationship between sperm chromatin and the TAC of semen (P=0.92, r=0.01). Additionally, there was no significant correlation between Se, Zn, or Cu concentration (P>0.05) and Fe concentration, which had a partially positive relationship with the chromatin state of sperm (P=0.24, r=0.20). The trace metal elements in the seminal fluid did not play a significant role in the status of sperm chromatin.

Geological Structure Control on the Formation of Metal Mineralization at Quartz Veins in Jendi Village, Wonogiri Regency, Central Java

Quartz veins in the Jendi area and its surroundings are formed by geological structures with distributions and patterns that need to be known. This study uses data on striation, quartz vein orientation, and metal content in quartz veins. The use of this data aims to determine the relationship between the vein direction pattern and its metal mineral content with the main structure that forms it. The results of this study can be useful in determining the structural model and distribution of veins in the study area. The research method was carried out through a series of field and laboratory work. Fieldwork includes measuring striation data, measuring the orientation of quartz veins, and taking quartz vein samples. Studio work includes stereographic analysis of striation data, rosette diagram analysis of vein measurement data, and analysis of metallic element content of quartz veins. The quartz vein mineralization zone in the study area is controlled by a right slip fault with a northwest-southeast trend that forms a transtension zone with a north-south trend. The north-south trending veins are generally thick, long/continuous, and have a high metal content.

Mechanism of bonding, surface property, electrical behaviour, and environmental friendliness of carbon/ceramic composites produced via the pyrolysis of coal waste with polysiloxane polymer

A simple mixing-pressing followed by thermal curing and pyrolysis process was used to upcycle coal waste into high-value composites. Three coal wastes of different physicochemical properties were investigated. The hypothetical mechanisms of bonding between the coal particles and the preceramic polymer are presented. The textural properties of the coals indicated that the lowest volatile coal waste (PCD) had a dense structure. This limited the diffusion and reaction of the preceramic polymer with the coal waste during pyrolysis, thereby leading to low-quality composites. The water contact angles of the composites up to 104° imply hydrophobic surfaces, hence, no external coating might be required. Analysis of the carbon phase confirmed that the amorphous carbon structure is prevalent in the composites compared to the coal wastes. The dc volume resistivity of the composites in the range of 22 to 82 Ω-cm infers that the composites are unlikely to suffer electrostatic discharge, which makes them useful in creating self-heating building parts. The leached concentrations of heavy metal elements from the composites based on the end-of-life scenario were below the Toxicity Characteristic Leaching Procedure regulatory limits. Additionally, the release potential or mobility of the metals from the composites was not influenced by the pH of the eluants used. On the basis of the reported results, these carbon/ceramic composites show tremendous prospects as building materials due to these properties.Graphical

Environmental investigation on the use of a phosphogypsum-based road material: Radiological and leaching assessment

The transformation of phosphate ore into phosphoric acid results in the generation of high volumes of phosphogypsum (PG), an industrial by-product largely stockpiled worldwide. This solution, considered as the least damaging to the environment, constitutes a risk for the receiving environment due to the presence of harmful impurities such as heavy metals and radionuclides which hinder its large-scale valorization. This paper presents an environmental characterization of Moroccan phosphogypsum and an investigation on the environmental performance of a new lime (L) - fly ash (FA) treated phosphogypsum based road material. The concentration of metallic trace elements (Cr, Pb, Ni, Zn, Cu) in raw phosphogypsum ranged between 0.2 and 243 ppm, while its radioactivity reached 970 Bq/kg for Ra-226. The environmental performance of the proposed new road material (40% PG, 42% FA, 18% L) was evaluated using radiological risk indices besides static and dynamic leaching tests. The results showed a radioactivity reduction up to 82%, and an immobilization of metallic trace elements ranging from 25 to 100%. The stabilization/solidification mechanisms involved in the lime - fly ash treatment would be responsible for the fixation of these contaminants within the newly formed matrix.

Estimation of the Multielement Content in Rocks Based on a Combination of Visible–Near-Infrared Reflectance Spectroscopy and Band Index Analysis

Rock geochemical methods are effective for geological surveys, but typical sampling and laboratory-based analytical methods are time-consuming and costly. However, using visible–near-infrared spectroscopy to estimate the metal element content of rock is an alternative method. This study discussed the potential of hyperspectral estimation of Cu and its significant associated elemental content. Ninety-five rock samples were collected from the Kalatage Yudai copper–nickel deposit in Hami, Xinjiang. The effects of different spectral resolutions, spectral preprocessing, band indices, and characteristic band selection on the estimation of the element contents of Fe, Cu, Co, and Ti were investigated. The results show that when the spectral resolution is 5 nm, good results are obtained for all four metal elements, Fe, Cu, Co, and Ti, with the coefficients of determination R2 reaching 0.54, 0.59, 0.41, and 0.78, respectively. The best results are obtained for all transformed spectra with continuum removal, inverse transformation, continuum removal, and logarithmic transformation, respectively. In addition, the accuracy of the estimation models constructed by combining band indices and feature band selection was superior compared with full-band spectra for Fe (R2 = 0.654, MAE = 1.27%, and RPD = 1.498), Cu (R2 = 0.694, MAE = 20.509, and RPD = 1.711), Co (R2 = 0.805, MAE = 2.573, and RPD = 2.199), and Ti (R2 = 0.501, MAE = 0.04%, and RPD = 1.412). The results indicate that using band indices can provide a more accurate estimation of metal element content, providing a new technical method for the efficient acquisition of regional mineralization indicator element content distribution.

Utilizing X-ray fluorescence (XRF) method to evaluate the content of metal elements in soil and their effects on the total phenolic and flavonoid contents of some medicinal plants.

Soil factors, especially metal elements in the soil, play a significant role in forming and accumulating secondary metabolites, which determine the medicinal properties of medicinal herbs. In this study, the concentrations of some metal elements (K, Mn, Fe, Cu, Zn, and Cr) in Cam Mountain and Tinh Bien Town, An Giang Province, Vietnam, were determined using the XRF method. We simultaneously determined the total phenolic and flavonoid content of some medicinal herbs collected from the collected soil sample areas, thereby assessing the influence of these elements on the formation of secondary metabolites in medicinal plants. The results showed that K, Mn, and Cr were mainly concentrated in the topsoil and transition layers; Fe and Cu elements tended to concentrate in the transition layer and the subsoil when surveying the soil profile. K, Mn, Cu, and Cr concentrations were more focused in Tinh Bien area, while Fe and Zn had higher concentrations at Cam Mountain. Additionally, results from evaluating the relationship between the content of the elements in the soil and the content of two active compounds also showed the correlation regression model between Zn and flavonoid expression by level 4 at the 5% significance level. Thus, the nonlinear model is suitable for evaluating the relationship between the content of metal elements in the soil and the active compound in medicinal plants.

INVESTIGATION INTO THE PESTICIDES RESIDUES IN SESAME, MILLET, RICE, AND GUINEA CORN GROWN AROUND THE HADEJIA-KOMADUGU-YOBE RIVER AREA IN YOBE STATE, NIGERIA.

Application of pesticides during crop production often results in pesticide residue, a significant source of heavy metals in the harvested crops. This raises concern for consumers' health due to the potentially deleterious effects of pesticides on animals, particularly humans. This study examined the levels of pesticide residues using a gas chromatography-mass spectrometry (GC-MS) system and heavy metal elements concentration using Atomic Absorption Spectrometry (AAS) in four food crops (Sesame, Millet, Rice, and Guinea corn) cultivated in (Gwio-Kura) Gashua and Hadejia towns in Nigeria. The results disclosed that Sesame was the only crop with Dichlorvos from both Gashua and Hadejia, surpassing the WHO's limit for pesticide residue concentrations, and that the Hadejia samples had higher levels than the Gashua samples. The study also detected traces of Cadmium (Cd), Lead (Pb), Nickel (Ni), and Manganese (Mn) in the crops, but they were below the permissible intake levels established by FAO/WHO. However, Arsenic (As) and Chromium (Cr) exceeded the FAO/WHO limits and may entail serious health problems such as kidney damage and cancer. Mercury (Hg) was not detected in any of the crops. Our findings suggest health authorities monitor and regulate heavy elements intake in food crops, especially those with high toxic contamination, to prevent adverse health effects such as the kidney disease on humans and animals, currently prevalent in the area.&#x0D;

Contamination of selected heavy metals in Limnothrissa miodon (Boulenger, 1906) in the four strata of Lake Kariba Zambia: are the consumers at risk?

Pollution of aquatic ecosystems is one of the major challenges affecting many countries of the world. Heavy metal pollutants, in particular, threaten the life of aquatic organisms (fauna and flora) and, more importantly, humans who consume aquatic products as a critical source of proteins. In the present study, the concentrations of selected heavy metals (cobalt- Co, Chromium-Cr, nickel- Ni and manganese- Mn) in Limnothrissa miodon, locally known as ‘Kapenta’ were assessed using the Microwave Plasma Atomic Emission Spectrometer (MP AES) 4200 at the Zambia Agricultural Research Institute (ZARI). The fish was collected from Lake Kariba, Zambia, which is divided into four fisheries management strata (I, II, III, and IV). The health risks to consumers were evaluated using the Estimated Daily Intake (EDI), Target Hazard Quotient (THQ) and Hazard Index (HI). Analysis of variance (ANOVA) was used to assess the difference in the means of heavy metal concentration across the four strata for each element. The concentrations of all the heavy metal elements were within the permissible limits considered to be safe for human consumption based on the Food and Agriculture Organization (FAO) standards. However, the concentration of individual heavy metal elements varied significantly across the strata with stratum I and II showing higher levels in general except for Mn which was highest in stratum II and III compared with the other strata. Furthermore, Mn concentration was the highest in all the strata and the highest concentration was observed in the fish from stratum II. The EDIs, THQs and HIs of each heavy metal element did not show any threat to consumers of the fish from the lake. Further studies are required to better understand the potential sources of heavy metals and to regularly monitor existing activities that may elevate the concentration levels.

Distribution of Minor and Major Metallic Elements in Residential Indoor Dust: A Case Study in Latvia.

The coronavirus disease 2019 (COVID-19) pandemic has not only brought considerable and permanent changes to economies and healthcare systems, but it has also greatly changed the habits of almost the entire society. During the lockdowns, people were forced to stay in their dwellings, which served as a catalyst for the initiation of a survey on the estimation of the metallic element content in residential indoor dust in different parts of Latvia. This article presents the study results obtained through the analysis of collected dust samples from 46 dwellings, both in the capital of Latvia, Riga, and in smaller cities. Two methods were employed for indoor dust collection: vacuum sampling and manual sampling with a brush and plastic spatula. After microwave-assisted acid extraction, the samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS) in terms of the major (Na, K, Ca, Mg, Al and Fe) and minor (Mn, Ni, Co, Pb, Cr, As, Ba, Li, Be, B, V, Cu, Zn, Se, Rb, Sr, Cd, La, Ce and Bi) elements. For the data analysis, principal component analysis was performed. Among the measured metals, the highest values were determined for the macro and most abundant elements (Na > K > Ca > Fe > Mg > Al). The concentration ranges of the persistently detected elements were as follows: Pb, 0.27-1200 mg kg-1; Cd, 0.01-6.37 mg kg-1; Ni, 0.07-513 mg kg-1; As, 0.01-69.2 mg kg-1; Cu, 5.71-1900 mg kg-1; Zn, 53.6-21,100 mg kg-1; and Cr, 4.93-412 mg kg-1. The critical limit values of metallic elements in soil defined by the legislation of the Republic of Latvia (indicating the level at or above which the functional characteristics of soil are disrupted, or pollution poses a direct threat to human health or the environment) were exceeded in the following numbers of dwellings: Pb = 4, Ni = 2, As = 1, Cu = 16, Cr = 1 and Zn = 28.

Study of Heavy Metal Content in Lola Snail (Trochus niloticus) in The Karang Island of Central Tapanuli Regency

Research on the analysis of heavy metal content in the waters of Karang Island, Central Tapanuli Regency aims to know the metal content in Lola Snail meat, sediment, and Lola Snail shells. The research method begins with taking samples of Lola snails and sediments on Karang Island and preparing the samples. Then, the samples were analyzed by AAS (Atomic Absorption Spectrometry) to determine the content of heavy metal elements in the meat of Lola Snail, followed by XRD (X-Ray Diffraction) testing to determine the content of heavy metal elements in sediments, and also testing with EDX (Energy Dispersive X-Ray) to determine the content of heavy metals in the shell. The results of the analysis on the AAS test showed that the order of heavy metal concentrations in Lola snail meat at station I was Zn Cr Cu Cd Pb, while at station II was Zn Cu Cr Cd Pb. The results of the sequence of heavy metal concentrations using XRD in sediments around Karang Island at the station I was Zn Cr Cu Cd Pb, while at station II was Zn Cd Cu Cr Pb. The results of the analysis on the shells of Lola snails using EDX at both stations showed they did not contain heavy metal elements (Pb, Cd, Cu, Cr, and Zn), but only contained O, Ca, Mg, Na, Al, and Si elements.

An evaluation of elemental enrichment in rocks: In the case of Kısacık and its neighborhood (Ayvacık, Çanakkale/Türkiye)

In this study, the enrichment of the major oxide, trace element/heavy metal and rare earth element contents of the rocks outcropping in Kısacık and its vicinity (Ayvacık-Çanakkale/Türkiye) were investigated. The rocks in the field were handled in 5 groups, and whole rock analyses were carried out for 22 samples collected representing these rock groups and Element Enrichment Factor (EEF) of the major oxide, trace element/heavy metal and rare earth element contents of the rocks were calculated. As a result, it was determined that the Kısacık volcanics were enriched in SiO2, Fe2O3, K2O, Be, Co, Cs, Th, U, W, La, Eu, Tm, Yb, Lu, Mo, As, Cd, Sb, Bi and Hg elements at a rate of &gt;1 to &gt;150 according to the upper crust values, and the Fe2O3, MgO, CaO, TiO2, P2O5, MnO, Cr, Sc, Co, Nb, Sr, Mo, Cu, Ni, Cad, Sb, Bi, V, Cu and Cd concentrations of the Ophiolitic Mélange were enriched in ratios ranging from &gt;1 to &gt;36 according to the upper crust values. It has been also observed that the listvenitic rocks in the Ophiolitic Mélange are enriched in Cr, Co, Ni, As and Hg elements compared to the upper crust. As to Kazdağ Group, MgO, CaO, K2O, MnO, Cr, Co, Ta, U, W, Mo, Cu, Ni, As and Cd were enriched. Listvenite were enriched in SiO2, Fe2O3, MgO, Mn, Cr, Co, Ni, As, Sb and Hg at a rate of &gt;1 to &gt;32 according to the upper crust values. When the rocks in the area were evaluated together, some oxides (e.g., CaO, MgO, Fe2O3, TiO2) and elements (e.g., Cr, Ni, Co) were enriched due to parental rock, while some oxides (e.g., SiO2, K2O and MnO) and elements (As, Sb, Hg) were enriched due to epigenic processes such as hydrothermal alteration and weathering.

Assessing the influence of geological stress induced damage and initial pH levels on the metal leaching behaviors of cemented paste backfill

Cemented paste backfill (CPB) is generally considered environmentally friendly when used in mining operations. However, the combination of geological stresses and groundwater seepage in an underground environment may cause the metallic elements contained in CPB to escape confined areas and potentially pollute the external environment. In this paper, geological stress-induced damage to CPB and the initial pH levels of the surrounding environment are assessed to determine their influences on the metal leaching behavior of CPB. Research methods used in the analysis include component characterization, static leaching tests, and kinetic theory analysis. The research results show that: as damage to CPB increased, both the pH and conductivity of the leachate increased, while the concentration of metallic elements in the leachate also increased except for aluminum (Al). Different metallic elements showed various leaching behaviors as the initial pH of the leaching solution increased. The release process of metallic elements from CPB can be segmented into three separate stages: the surface release stage, the internal release stage, and the adsorption and precipitation stage. Kinetic equations are obtained to describe the release rate of metallic elements. The leaching process is a dynamic equilibrium system formed by the release, absorption, and precipitation of metallic elements in the leachate. This research provides data for the evaluation of environmental effects on CPB.