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Zhang, Yan y Vadim N. Gladyshev. "Comparative Genomics of Trace Element Dependence in Biology". Journal of Biological Chemistry 286, n.º 27 (12 de mayo de 2011): 23623–29. http://dx.doi.org/10.1074/jbc.r110.172833.
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Biological trace elements are needed in small quantities but are used by all living organisms. A growing list of trace element-dependent proteins and trace element utilization pathways highlights the importance of these elements for life. In this minireview, we focus on recent advances in comparative genomics of trace elements and explore the evolutionary dynamics of the dependence of user proteins on these elements. Many zinc protein families evolved representatives that lack this metal, whereas selenocysteine in proteins is dynamically exchanged with cysteine. Several other elements, such as molybdenum and nickel, have a limited number of user protein families, but they are strictly dependent on these metals. Comparative genomics of trace elements provides a foundation for investigating the fundamental properties, functions, and evolutionary dynamics of trace element dependence in biology.
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Liu, Xiao Ling, Jian Wang, Yong Hui Song y Ping Zeng. "Response Surface Optimization of Trace Element Requirement for the Production of Volatile Fatty Acids from Excess Sludge". Advanced Materials Research 878 (enero de 2014): 663–69. http://dx.doi.org/10.4028/www.scientific.net/amr.878.663.
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Anaerobic microorganisms involved in VFAs fermentation have inherent requirements for trace metals. It is inferred that excess sludge contains inadequate amounts of bioavailable trace metals for high-rate VFAs fermentation. The unavailability of these trace metals is probably the primary reason of poor yield without any other obvious reason. However, trace metal requirements in VFAs fermentation are not often reported in literature. Therefore, minimum requirements for trace metals including Zn, Co, Cu, Fe and Mn in VFAs fermentation from excess sludge were investigated. Firstly, the effect of each trace metal element on the VFAs production was investigated, respectively. And then, response surface methology was employed to optimize the requirement conditions of these five trace elements. The results showed that these five metal elements had the potential to enhance the production of VFAs, and the improved influences were as follows: Fe > Co > Mn > Cu > Zn. However, the production of VFAs decreased obviously with a further increase of each trace element. The optimal mixed conditions of these five trace elements were found to be 0.0982% Fe, 0.0047% Co, 0.0053% Zn, 0.0038% Cu and 0.0936% Mn. Under the optimal conditions, the concentration of VFAs reached 8410 mg/L, and increased by 2.5 times compare with the control. Finally, the consistent results between the prediction and the experiment indicated that the established polynomial model was feasible, and VFAs production could be described well by this model.
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Semenov, M. Yu, V. A. Snytko, Yu M. Semenov, A. V. Silaev y L. N. Semenova. "Metals composition of the surface waters of the Southern Baikal region and its connection with landscape and geological conditions". Доклады Академии наук 486, n.º 5 (20 de junio de 2019): 613–19. http://dx.doi.org/10.31857/s0869-56524865613-619.
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The metal composition of water and bottom sediments of southern Lake Baikal tributaries was studied and the water migration coefficients for micro- and trace elements were calculated. The map showing the study area divided into zones according to their ability to provide the certain water quality was drawn. The significant differences in mineralization, macro- and trace element composition between Lake Baikal water and tributary waters were found out. It was shown that values of water migration coefficients calculated for macro elements are similar in southern and main tributaries whereas coefficient values calculated for trace elements are quite different. This is due to dissolved matter sources such as rocks and deep ground waters which chemical composition is not typical for landscapes of Lake Baikal basin. The contribution of southern tributaries to macro element composition of lake water is between 7 and 15%, whereas tributaries contribution to trace element composition can hardly be evaluated because of higher element concentrations in riverine waters. The lower trace element concentrations in lake water with respect to riverine one is due to trace element migration in the form of complex organic compounds: long water residence time in lake favors to organic compounds decay by means of microbial- and photo-degradation followed by metal precipitation.
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Cleave y Crans. "The First-Row Transition Metals in the Periodic Table of Medicine". Inorganics 7, n.º 9 (6 de septiembre de 2019): 111. http://dx.doi.org/10.3390/inorganics7090111.
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In this manuscript, we describe medical applications of each first-row transition metal including nutritional, pharmaceutical, and diagnostic applications. The 10 first-row transition metals in particular are found to have many applications since there five essential elements among them. We summarize the aqueous chemistry of each element to illustrate that these fundamental properties are linked to medical applications and will dictate some of nature’s solutions to the needs of cells. The five essential trace elements—iron, copper, zinc, manganese, and cobalt—represent four redox active elements and one redox inactive element. Since electron transfer is a critical process that must happen for life, it is therefore not surprising that four of the essential trace elements are involved in such processes, whereas the one non-redox active element is found to have important roles as a secondary messenger.. Perhaps surprising is the fact that scandium, titanium, vanadium, chromium, and nickel have many applications, covering the entire range of benefits including controlling pathogen growth, pharmaceutical and diagnostic applications, including benefits such as nutritional additives and hardware production of key medical devices. Some patterns emerge in the summary of biological function andmedical roles that can be attributed to small differences in the first-row transition metals.
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Doherty, G. B., D. Coomans y G. J. Brunskill. "Modelling natural and enhanced trace metal concentrations in sediments of Cleveland Bay, Australia". Marine and Freshwater Research 51, n.º 8 (2000): 739. http://dx.doi.org/10.1071/mf98141.
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The major element and trace metal analytical results of a strong acid digestion have been used to model natural and enhanced trace metal concentrations in surface sediment samples from Cleveland Bay. The natural ranges in concentration of cadmium, cobalt, copper, nickel, lead and zinc in sediments have been modelled by multiple linear regression using major elements as independent variables. Sites that exceed the upper 95% prediction interval of the regression model of the natural range in concentration are classified as enhanced. Enhancement of sites by metals derived from anthropogenic sources is characterized by enhancement of cadmium, copper, lead or zinc, and can be identified by Principle Components Analysis. Sites that contain metals derived from anthropogenic sources occur within the intertidal and near-shore sediments of western Cleveland Bay. No evidence of trace metals derived from anthropogenic sources was found within the sediments of the central bay.
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Dobrinas, Simona, Alina Soceanu, Gabriela Stanciu, Viorica Popescu y Luiza Georgiana Arnold. "Trace element levels of three mushroom species". Analele Universitatii "Ovidius" Constanta - Seria Chimie 24, n.º 1 (1 de junio de 2013): 39–42. http://dx.doi.org/10.2478/auoc-2013-0008.
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AbstractThe aim of this study was to determine Cu, Fe and Cr contents of three species of fresh mushrooms and canned mushrooms: white and brown champignon (Agaricus bisporus) and Pleurotus Ostreatus. Were analyzed various plant parts: stem, cap and cuticle of fresh mushrooms and only stem and cap for canned mushrooms. The levels of trace metals of mushroom samples collected from regions of Romania, Poland and Turkey were determined by UV/Visible spectrometry - standard addition method after digestion method. The contents of investigated trace metals in mushroom samples were found to be in the range of 0.01 - 2.26 mg/Kg for chromium, 2.02 - 430.67 mg/Kg for copper and 240.40 - 7952.89 mg/Kg for iron. The iron content was found to be higher than those of the other two minerals in all the samples. Mushrooms species in the highest levels of trace elements were found white champignon for Cu and Fe and brown champignon for Cr.
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ORTEGA, RICHARD. "MICRO-PIXE FOR SINGLE CELL ANALYSIS". International Journal of PIXE 22, n.º 01n02 (enero de 2012): 51–56. http://dx.doi.org/10.1142/s0129083512400220.
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The knowledge of the intracellular distribution of biological relevant metals is important to understand their mechanisms of action in cells, either for physiological, toxicological or pathological processes. However, the direct detection of trace metals in single cells is a challenging task that requires sophisticated analytical developments. The combination of micro-PIXE with RBS and STIM (Scanning Transmission Ion Microscopy) allows the quantitative determination of trace metal content within sub-cellular compartments. The application of STIM analysis provides high spatial resolution imaging (< 200 nm) and excellent mass sensitivity (< 0.1 ng). Application of the STIM-PIXE-RBS methodology is absolutely needed when organic mass loss appears during PIXE-RBS irradiation. This combination of STIM-PIXE-RBS provides fully quantitative determination of trace element content, expressed in μg/g, which is a quite unique capability for micro-PIXE compared to other micro-analytical methods such as the electron and synchrotron x-ray fluorescence. Examples of micro-PIXE studies for sub-cellular imaging of trace elements in various fields of interest will be presented: in patho-physiology of trace elements involved in neurodegenerative diseases such as Parkinson's disease, and in toxicology of metals such as cobalt.
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Budko, D. F. y D. M. Martynova. "Trace element uptake assessment in the planktonic biofiltration system". Океанология 59, n.º 1 (18 de abril de 2019): 33–44. http://dx.doi.org/10.31857/s0030-157459133-44.
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The concentration of trace elements (Fe, Mn, Cr, Co, Ni, Cu, Pb, Cd, As) through the planktonic food chain of the White Sea have been studied by the experimental approach. The experiment included zooplankton sampled in a reference area feeding on a seston contained the different trace metals concentrations. Seston sampled in the st. Chupa was enriched by Fe, Cu, Pb, Cr, Co, As, and Ni comparing to the seston from st. Kartesh (reference area). The differences in the concentrations of the suspended particular matter and of the indicator elements of a terrigenous admixture (Al, Ti, Zr) evidence on higher natural background of the trace metals’ content in the seston from st. Chupa due to higher contribution of the minerals. Zooplankton that fed on the seston characterised by higher trace elements’ content has accumulated Fe, Mn, and Cr, at a less degree, Ni, Co, Pb, and Cu; particularly, these were the elements which content were high in seston. Despite Mn content in seston did not differ between two treatments, this element was accumulated by the zooplankton, but had low content in faecal pellets. This tells about the highest Mn assimilation by the zooplankton; this element may become the most bioavailability. When comparing the trace element content between the seston and the faecal pellets, the concentrations of the most elements in faecal pellets are lower comprising as low as Zn – 72%; Mn – 24; Cu – 97; Pb – 62; Cr – 99; Co – 78; Ni – 87; As – 96; Cd – 65% of the concentration in the seston.
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Zhang, Qing Wei, She Li Chai, Jing Cai y Li Na Gao. "Baseline Concentrations of Trace Metals in Grassland Topsoils from West Jilin Province, Northeast China". Advanced Materials Research 347-353 (octubre de 2011): 2140–45. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.2140.
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The objective of this study was to determine the baseline concentrations of trace elements in grassland topsoils from 155 soil sampling sites in West Jilin province, Northeast China, to establish the relationships between the trace metal contents and soil physicochemical properties and major oxide contents and among trace metal concentrations themselves, and to identify the possible sources of trace element in soils. The baseline concentrations of trace elements(mg/kg) were: As 3.12-14.18, B 16.17-49.08, Cd 0.037-0.127, Co 0.96-15.28, Cr 18.87-60.83, Cu 10.81-24.75, Hg 0.004-0.035, Mn 171.25-657.87, Mo 0.08-1.15, Ni 6.79-30, Pb 12.58 -26.08, Se 0.03-0.36, and Zn 18.93-61.03. The upper baseline limits of these elements were all less than the Chinese Environmental Quality Standard for Soils, the Dutch Intervention Values for Soils, implying that trace element contents in the studied soils were of the safety levels.Fe2O3 and Al2O3 had stronger correlations with most trace elements than other oxides, and Co,Cr,Cu,Mn, Ni were highly correlated one another. Three types of geochemical associations were distinguished from this study:the first association involving As,Co,Cr,Cu,Mn,Mo,Ni,Pb,Zn,Al2O3 and Fe2O3 was mainly associated with Al,Fe-Mn oxides and/or with the Al-bearing clay minerals, suggesting that the trace elements were mainly derived from lithogenic and pedogenic processes; the second association including Se, Hg, Cd, CaO and organic carbon was mainly associated with organic matter and calcium oxides, showing that Se,Hg and Cd were mainly contributed by anthropogenic sources; the third association containing B, Na2O, K2O, MgO, pH, and electrical conductivity was mainly associated salinization processes of soils, implying that alkaline pH and high Na contents would enhance B concentration of soils.
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Stafilov, Trajče y Irina Karadjova. "Atomic absorption spectrometry in wine analysis". Macedonian Journal of Chemistry and Chemical Engineering 28, n.º 1 (15 de junio de 2009): 17. http://dx.doi.org/10.20450/mjcce.2009.218.
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This article reviews methods for the determination and identification of trace elements in wine by using atomic absorption spectrometry (AAS). Wine is one of the most widely consumed beverages and strict analytical control of trace elements content is required during the whole process of wine production from grape to the final product. Levels of trace elements in wine are important from both points of view: organoleptic – Fe, Cu, Mn and Zn concentrations are directly related to the destabilization and oxidative evolution of wines, and toxicological – toxic elements content should be under the allowable limit, wine identification. The identification of metals in wine is subject of increasing interest since complexation may reduce their toxicity and bioavailability. AAS is one of widely used methods for routine analytical control of wine quality recommended by the International Organization of Vine and Wine. Two main approaches – preliminary sample digestion and direct instrumental measurement combined with AAS for trace element determination in wines are reviewed and discussed. Procedures for various sample pretreatments, for trace element separation and preconcentration are presented. Advances in metal identification studies in wines based on AAS are presented.
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Ma, Yamin y Andrew W. Rate. "Metals adsorbed to charcoal are not identifiable by sequential extraction". Environmental Chemistry 4, n.º 1 (2007): 26. http://dx.doi.org/10.1071/en06051.
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Environmental context. Charcoal is widespread in soils and may be a major component of soil organic matter. Trace metal ions in soils are predominantly associated with solid phase materials, including charcoal, and the identity of the solid phase and the mechanisms of association influence the geochemical behaviour of metals. Metals associated with soil mineral phases are estimated using techniques such as selective sequential extraction, and the sorption reactions of metal ions are well understood. Much less is known about the associations of trace metals with natural charcoal, and metals associated with charcoal in soils are likely to be misidentified in sequential extraction procedures. Abstract. Given that up to 50% of the soil carbon store can consist of charcoal, it is possible that trace elements can become immobilised through their interaction with natural charcoal. Hence, natural charcoal may be a significant sink that has yet to be accounted for in trace element biogeochemical cycles. Testing this hypothesis becomes problematic considering the typically small size (<53 µm) of charcoal particles that occur naturally in Australian soils, making isolation and analysis of natural soil charcoal difficult. Therefore, in this study, we test the robustness of a typical sequential extraction technique by applying it to naturally occurring charcoal that had been spiked with five different concentrations of metal ions (Al3+, Cr3+, Cu2+, Ni2+, Zn2+, Cd2+, Ag+, Pb2+). The method was then applied to contrasting soils mixed with this spiked charcoal. The sequential extraction scheme consisted of the following five extractions the in order: (1) sodium acetate (targeting the adsorbed-exchangeable-carbonate fraction), (2) sodium pyrophosphate (organic fraction), (3) ammonium oxalate (amorphous iron/manganese oxides), (4) hydroxylamine hydrochloride (crystalline iron/manganese oxides) and (5) residual (aqua regia digest). The majority of metals added to the charcoal were extracted in the fractions targeting both the amorphous and crystalline iron and manganese oxides, at low additions of metal ions. At higher additions of metals, the metals were mostly extracted from charcoal in the adsorbed-exchangeable-carbonate fraction. When the spiked charcoal was added to soils, a trend similar to the charcoal-only experiment was observed in the sequential extraction data. Higher concentrations of metals (compared with the control) were extracted for the charcoal-amended soils, in the same fractions as in the charcoal-only extractions. Since the concentration of metals extracted in the various extractants changed with increasing metal loads on charcoal, sequential extractions cannot be used to identify the contribution of metals from the charcoal pool. Therefore, a potentially large pool of trace elements could be misrepresented when sequential extraction techniques are applied, particularly for soils in which there is a large concentration of charcoal. Hence, there is still a large gap in knowledge with regard to the significance of charcoal in ‘real’ soils, particularly with respect to the role of charcoal as a trace element sink.
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Okochi, Haruno. "Ultra-trace element determination for metals - State of the art." Bulletin of the Japan Institute of Metals 27, n.º 3 (1988): 200–207. http://dx.doi.org/10.2320/materia1962.27.200.
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Giouri, K., M. Vavelidis, V. Melfos y L. Papadopoulou. "ASSESSMENT OF SELECTED METALS ENRICHMENT IN SEDIMENTS FROM PALEA KAVALA RIVER, NE MACEDONIA, NORTHERN GREECE". Bulletin of the Geological Society of Greece 50, n.º 4 (28 de julio de 2017): 2137. http://dx.doi.org/10.12681/bgsg.14266.
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In surface aquatic systems, trace elements and especially heavy metals accumulate in sediments. Thus, the determination of sediment chemical characteristics is critical in the assessment of an aquatic environment’s quality. Thirteen sediment samples from Palea Kavala river (NE Macedonia, Greece) were studied for their content in Al, Fe, Cu, Cd, Mn, Pb, Zn. In order to evaluate the metal enrichment for environmental purposes, two geochemical indices were employed: Enrichment Factor (EF) and Geoaccumulation Index (Igeo). According to the results, Al was the most abundant major element in sediments with Fe and Mn to follow. Trace element content followed the order Pb>Zn>Cu>Cd. EF values revealed that samples are enriched in Cd and Pb, while Igeo values also suggested that there is considerable contamination concerning Cd and Pb. It is concluded that ore mineralizations which occur in Palea Kavala region contribute to the elevated concentrations of all the studied elements, since they comprise mainly Fe-Mn metal assemblages including minerals such as pyrite, goethite, chalcopyrite, galena, sphalerite and pyrolousite.
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Jing, Li, Li Fadong, Liu Qiang, Song Shuai y Zhao Guangshuai. "Spatial distribution and sources of dissolved trace metals in surface water of the Wei River, China". Water Science and Technology 67, n.º 4 (1 de febrero de 2013): 817–23. http://dx.doi.org/10.2166/wst.2012.608.
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For this study, 34 water samples were collected along the Wei River and its tributaries. Multivariate statistical analyses were employed to interpret the environmental data and to identify the natural and anthropogenic trace metal inputs to the surface waters of the river. Our results revealed that Zn, Se, B, Ba, Fe, Mn, Mo, Ni and V were all detected in the Wei River. Compared to drinking water guidelines, the primary trace metal pollution components (B, Ni, Zn and Mn) exceeded drinking water standard levels by 47.1, 50.0, 44.1 and 26.5%, respectively. Inter-element relationships and landscape features of trace metals conducted by hierarchical cluster analysis (HCA) identified a uniform source of trace metals for all sampling sites, excluding one site that exhibited anomalous concentrations. Based on the patterns of relative loadings of individual metals calculated by principal component analysis (PCA), the primary trace metal sources were associated with natural/geogenic contributions, agro-chemical processes and discharge from local industrial sources. These results demonstrated the impact of human activities on metal concentrations in the Wei River.
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Outridge, P. M., G. Veinott y R. D. Evans. "Laser ablation ICP-MS analysis of incremental biological structures: archives of trace-element accumulation". Environmental Reviews 3, n.º 2 (1 de abril de 1995): 160–70. http://dx.doi.org/10.1139/a95-007.
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Incremental growth layers occur in the hard structures of many types of organisms (tree xylem, mollusc shells, vertebrate teeth, otoliths, scales, etc.). Microprobes have previously shown that these layers contain archival information about an organism's chemical environment. However, trace elements, including metals, are generally undetectable with these instruments. A relatively new technique, laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS) promises multielement analytical capability with extremely low detection limits (conservatively, <1 ppm), combined with very fine spatial resolution (down to 30–100 μm beam diameter). Fish otoliths and vertebrate tooth cement and dentin offer the greatest potential for retrieving element archival information, because they are not subject to resorption, and reflect the organism's exposure to or accumulation of trace elements from the ambient environment. Other structures are less promising, because they exhibit element mobility between growth layers (tree rings), or are subject to metabolic turnover and resorption (scales, bones, shells). While the LA-ICP-MS technique is novel in the biological sciences, the few studies available indicate that reproducible, year-by-year data on metal accumulation or exposure will probably be retrievable from many types of incremental structures. The main problem currently is the lack of solid standard reference materials which match the physicochemical properties of hard biological tissues.Key words: laser ablation, mass spectrometry, trace metals, environmental pollution, calcified tissues.
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Halden, N. M. y L. A. Friedrich. "Trace-element distributions in fish otoliths: natural markers of life histories, environmental conditions and exposure to tailings effluence". Mineralogical Magazine 72, n.º 2 (abril de 2008): 593–605. http://dx.doi.org/10.1180/minmag.2008.072.2.593.
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AbstractOtoliths, the earbones of teleost (bony) fish, are constructed from alternating layers of aragonite and protein. Laser ablation inductively coupled plasma mass spectrometry and proton-induced X-ray emission are used to obtain spatially well-resolved trace element line-scans that show trace-element concentrations are correlated with the annular structure. Zoned Sr and Zn signatures are common whereas other elements such as Cu, Pb, Li and Cs can be related to the proximity of mineral deposits. Aragonite in otoliths can incorporate a wide range of trace elements at the low-ppm level including alkali- and alkaline-earth elements and base metals; Se has also been detected in proximity to coal mines. These trace elements, in combination with the annular structures, are an important archive for recording information on environments occupied by fish, environmental change and exposure to pollutants.
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MURAO, SATOSHI y SOEY H. SIE. "PIXE AS AN ESSENTIAL TOOL FOR RARE METAL BENEFICIATION AND EXPLORATION". International Journal of PIXE 05, n.º 02n03 (enero de 1995): 97–103. http://dx.doi.org/10.1142/s0129083595000137.
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We have examined tin-polymetallic ore, a complex mixture of cassiterite (SnO2) and sulfides, by micro-PIXE. Tin-polymetallic ore is one of the major sources of technologically important “rare metals”, especially of indium and bismuth, usually as trace elements. In addition to such rare metals, silver is another important trace component in the ore. But the trace elemental distribution of tin-polymetallic deposit has not well been described due to the small size of constituent minerals, complex ore texture, and lack of analytical method to detect trace elements in a small area. PIXE with a proton microbeam could be an effective tool to solve this problem by delineating the distribution of these trace elements among carrier minerals with the required sensitivity. Thus we have applied PIXE with the CSIRO’s proton microprobe to a tin-polymetallic ore from Canada. The result showed that micro-PIXE is an essential tool to study trace element distribution in such a complex ore.
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Mattigod, S. V., P. F. Pratt y E. B. Schalscha. "Trace Metal Speciation in a Soil Profile Irrigated with Waste Waters". Water Science and Technology 17, n.º 9 (1 de septiembre de 1985): 133–42. http://dx.doi.org/10.2166/wst.1985.0087.
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A chemical equilibrium computer model: GEOCHEM, was used to predict the trace metal behavior in a soil profile if subjected to a long-term irrigation with waste waters. Various categories of interactions such as acid-base equilibria, soluble complex formation of metals with organic and inorganic ligands, dissolution-precipitation reactions and ion-exchange reactions were included in simulation. The metal-soluble organic interactions were accounted for by a mixture model. The computations included a 10 metal - 15 ligand system with 262 soluble complex species and 21 possible solid phases. The results predicted that a major fraction of alkali elements in solution tend to be in free ionic forms, whereas, major fractions of the alkaline earths were predicted to be present in adsorbed and/or precipitated forms. In marked contrast, significant soluble fractions of transition series metals were predicted to be in adsorbed and/or complexed forms. The degree of attenuation of these transition series elements moving through the soil profile seems to be governed mainly by the degree of adsorption on soil surfaces and the tendency of these elements to form soluble organic complexes. The predicted mobilities of these elements in this soil profile was Cu > Ni > Zn > Cd. Application of this equilibrium model appears to provide a first approximation approach to simulate the trace element behavior in soil profiles.
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Sheppard, M. I., S. C. Sheppard y C. A. Grant. "Solid/liquid partition coefficients to model trace element critical loads for agricultural soils in Canada". Canadian Journal of Soil Science 87, Special Issue (1 de marzo de 2007): 189–201. http://dx.doi.org/10.4141/s06-061.
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Canadian consumers are demanding a sustainable agricultural industry as well as products delivered under Best Management Practices (BMPs). Trace element accumulation in soils may influence crop productivity, food quality and ecosystem and human health. Canada’s feed and foodstuff export industry has already faced cases of penalties for high trace element content [cadmium (Cd) in durum wheat]. Thus, it is imperative to be able to estimate the accumulation and potential short- and long-term impacts of trace elements in soil. A national-level Trace Element Indicator (TEI) based on present loadings of trace elements to agricultural land is in progress. An Expert Panel including Canadian, American and Australian experts guided the assembly of a proposed methodology for this TEI. The proposed TEI, described briefly here, is a critical load approach with a single expression of the risk of impact from single or multiple trace elements from multiple sources (manures, biosolids, effluents and fertilizers and natural processes), invoked in a stochastic manner. Two key data requirements are the current background levels of trace elements in soil, and the leachability of these trace elements. A survey of total and soluble concentrations of 54 elements in up to 112 soils was completed. Although preliminary in scope, these represent key soil series in Canada. From this, a database of the solid/liquid partition coefficient, Kd, was computed. These Kd values will be used to characterize the leachability of the trace elements. Key words: Cadmium, copper, zinc, lead, nickel, uranium, metals, Kd, distribution coefficient
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Lewis, V. D., S. H. Nam y I. T. Urasa. "Speciation of Trace Metals by Ion Chromatography with Element Selective Detectors". Journal of Chromatographic Science 27, n.º 8 (1 de agosto de 1989): 468–73. http://dx.doi.org/10.1093/chromsci/27.8.468.
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Sokol, Ella, Svetlana Kokh, Victor Sharygin, Victoria Danilovsky, Yurii Seryotkin, Ruslan Liferovich, Anna Deviatiiarova, Elena Nigmatulina y Nikolay Karmanov. "Mineralogical Diversity of Ca2SiO4-Bearing Combustion Metamorphic Rocks in the Hatrurim Basin: Implications for Storage and Partitioning of Elements in Oil Shale Clinkering". Minerals 9, n.º 8 (30 de julio de 2019): 465. http://dx.doi.org/10.3390/min9080465.
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This is the first attempt to provide a general mineralogical and geochemical survey of natural Ca2SiO4-bearing combustion metamorphic (CM) rocks produced by annealing and decarbonation of bioproductive Maastrichtian oil shales in the Hatrurim Basin (Negev Desert, Israel). We present a synthesis of data collected for fifteen years on thirty nine minerals existing as fairly large grains suitable for analytical examination. The Hatrurim Ca2SiO4-bearing CM rocks, which are natural analogs of industrial cement clinker, have been studied comprehensively, with a focus on several key issues: major- and trace-element compositions of the rocks and their sedimentary precursors; mineral chemistry of rock-forming phases; accessory mineralogy; incorporation of heavy metals and other trace elements into different phases of clinker-like natural assemblages; role of trace elements in stabilization/destabilization of Ca2SiO4 polymorphic modifications; mineralogical diversity of Ca2SiO4-bearing CM rocks and trace element partitioning during high-temperature–low-pressure anhydrous sintering. The reported results have implications for mineral formation and element partitioning during high-temperature–low-pressure combustion metamorphism of trace element-loaded bituminous marine chalky sediments (“oil shales”) as well as for the joint effect of multiple elements on the properties and hydration behavior of crystalline phases in industrial cement clinkers.
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Yaman, M., G. Kaya y M. Simsek. "Comparison of trace element concentrations in cancerous and noncancerous human endometrial and ovary tissues". International Journal of Gynecologic Cancer 17, n.º 1 (enero de 2007): 220–28. http://dx.doi.org/10.1111/j.1525-1438.2006.00742.x.
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Question of whether trace metal concentrations in tissues are increased or decreased in cancerous patients in comparison with noncancerous patients has not been answered yet, due to the fact that the data known in this field are rare and have contradictory results. Although Zn and Cu concentrations in serum and tissues of cancerous patients have extensively been studied, the precise role of these metals in carcinogenesis is not clearly understood. There are few studies on the concentrations of essential and toxic trace/minor metals in human tissue samples in comparison with serum and plasma samples. Trace metal concentrations including Cd, Cu, Zn, Fe, Mg, Ca, and Ni in both cancerous and noncancerous endometrial, ovary, and cervix uteri tissues were determined by atomic absorption spectrometry. The tissue samples were digested by using microwave energy. Slotted tube atom trap was used to improve the sensitivity of copper and cadmium in flame atomic absorption spectrometry determination. The concentrations of iron in cancerous endometrial tissues were found to be significantly higher than those in noncancerous samples (P< 0.01). On the contrary Fe, Zn concentration in cancerous endometrial tissue was found to be lower significantly than those in noncancerous samples (P= 0.005), whereas the other studied metals were not observed different. Furthermore, Cu and Ca concentrations in cancerous ovary samples were observed to be higher than those in noncancerous ovary tissues (P< 0.01 for Cu andP= 0.1 for Ca), whereas Mg, Fe, and Zn levels in cancerous ovary samples were not found to be different than those in noncancerous tissues.
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Fergusson, Jack E. "The significance of the variability in analytical results for lead, copper, nickel, and zinc in street dust". Canadian Journal of Chemistry 65, n.º 5 (1 de mayo de 1987): 1002–6. http://dx.doi.org/10.1139/v87-171.
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Street dust has frequently been used as a material for the monitoring of trace element pollution, and in particular for the metal lead. The value of the analytical data, as a measure of pollution, depends on understanding the spatial, temporal, and bulk characteristics of the dust. The influence of each of these factors on the variability of trace element analytical results has been investigated in order to determine whether or not the variations reflect differing pollution levels. The concentrations of the four metals Pb, Cu, Ni, and Zn have been measured in street dust collected from a variety of situations. Coefficients of variation > 20% (particularly for lead) for a series of samples have been taken as a guide to real differences in lead levels between samples in the series. An important factor in the variability of heavy metal levels in dust is the distribution of particle size within a sample. Concentrations of the trace metals fall and then rise as the particle size decreases from 1000 μm down to silt sized particles.
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Pacyna, Jozef M., M. Trevor Scholtz y Y. F. (Arthur) Li. "Global budget of trace metal sources". Environmental Reviews 3, n.º 2 (1 de abril de 1995): 145–59. http://dx.doi.org/10.1139/a95-006.
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Global emission inventories, being the key information for the global budgets of trace metals, have become available only recently. The latest information on emissions and sources of trace metals on a global scale is presented in this paper. As the global assessments are prepared on the basis of estimates of regional emissions, these latter data are also reviewed here. A comparison of the worldwide atmospheric emissions from natural and anthropogenic sources suggests that various human activities are the dominant source of many trace metals, including As, Cd, Pb, and Zn. A comparison of the atmospheric and aquatic emissions indicates that, for most of the trace metals, the annual anthropogenic inputs into water exceed the quantities emitted to the atmosphere. However, the largest quantities of trace metals are discharged to the terrestrial environment. So far, the Pb budget seems to be the most accurate owing to a large body of information available on this element. The largest emissions of Pb were estimated for gasoline combustion, contributing about two thirds of the total emissions to the atmosphere. Emissions from nonferrous metal production contributed about one quarter. Emissions from the European and Asian sources contributed each about one third of the global emissions, followed by emissions from sources in North America. A spatial distribution of the global Pb emissions is presented within a 1 × 1° grid system.Key words: trace metals, lead, global emission, emission map.
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YILMAZ, Hınç, Vugar ALİYEV, Zeliha KAYAALTI, Bülent YALÇIN y Tülin SÖYLEMEZOĞLU. "Levels of Trace Elements and Toxic Metals in Autopsy Renal Tissue Samples". Turkiye Klinikleri Journal of Medical Sciences 32, n.º 1 (2012): 7–14. http://dx.doi.org/10.5336/medsci.2010-20051.
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Arce, Silvia, Soledad Cerutti, Roberto Olsina, Mara R. Gomez y Luis D. Martnez. "Trace Element Profile of a Wild Edible Mushroom (Suillus granulatus)". Journal of AOAC INTERNATIONAL 91, n.º 4 (1 de julio de 2008): 853–57. http://dx.doi.org/10.1093/jaoac/91.4.853.
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Abstract Seventeen elements, Al, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, V, and Zn (macroelements and trace elements) were investigated by Atomic Spectrometries on a particular wild edible mushroom collected in the central region of Argentina during 2 different years in the same season. The metal content profile in Suillus granulatus samples is given. The found quantities of Na, K, Ca, Mg, Fe, P, V, and Al were 0.40, 10.84, 0.48, 0.30, 0.57, 4.24, 0.18, and 1.23 g/kg dry weight, respectively. The levels of Li, Cu, Zn, Cd, Co, Ni, Cr, and Mn were 0.98, 23.02, 22.30, 0.26, 0.16, 1.17, 0.90, and 28.75 mg/kg dry weight, respectively. Pb was not detected at the investigated levels. The results indicate that the levels of metals in the analyzed samples are not considered to be a health risk. In order to demonstrate the validity of our method, a recovery study was performed with acceptable results.
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Sokol, E. V., A. S. Deviatiiarova, S. N. Kokh, V. V. Reverdatto, D. A. Artemyev y V. Yu Kolobov. "Sulfides in the marbles of spurrite-merwinite facies: the Kochumdek River, East Siberia". Доклады Академии наук 489, n.º 2 (20 de noviembre de 2019): 174–78. http://dx.doi.org/10.31857/s0869-56524892174-178.
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In the marbles of the Kochumdek contact metamorphic aureole pyrrhotite, rasvumite, sphalerite, alabandite, wurtzite, galena, acanthite have been identified. Mineralogical diversity of sulphides is the consequence of the efficient crystal-chemical fractionation of trace elements under the PT‑conditions of spurrite-merwinite metamorphic facies. Trace element and isotope fingerprints of sulfides indicate that sedimentary parent rocks were the main source of sulfur and metals for sulfides mineralization.
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Baraj, Besnik, Luis Felipe Niencheski, Gilberto Fillmann y Luciano Hermanns. "Biochemical normalization of trace metals in Arctocephalus australis". Brazilian Journal of Oceanography 57, n.º 1 (marzo de 2009): 1–6. http://dx.doi.org/10.1590/s1679-87592009000100001.
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Initially, the heart concentration data does not seem relevant for use as a bioindicator, mainly due to its low concentration level. After applying a normalizing procedure, the heart results were a better Hg bioindicator (preconcentration coefficient 43.1) than those of the kidney (preconcentration coefficient 8.6). Cadmium preconcentration coefficients were 128.1, 195.3 and 5.2 for liver, kidney and heart, respectively, demonstrating the high accumulative capacity especially for the liver and kidneys. Iron is proposed as a normalizing element for the definiton of the regional natural biochemical population of the metals. In general, positive correlation coefficients were found between Fe and other metals.
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Budiyanto, Fitri. "GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROPHOTOMETRY SEBAGAI METODE ANALISIS LOGAM BERAT". OSEANA 42, n.º 3 (30 de octubre de 2017): 9–20. http://dx.doi.org/10.14203/oseana.2017.vol.42no.3.80.
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GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROPHOTOMETRY AS A METHOD FOR ANALYZING HEAVY METAL. Heavy metal, mostly present in a (ultra) trace-level, becomes one of the hazardous pollutants due to its toxicity, bioaccumulative, biomagnification characters. Conducting a micro analysis of these trace-level pollutants, a sensitive instrument and method are strongly recommended. Graphite Furnace Atomic Absorption Spectrophotometer (GFAAS) offers a solution for the challenge. It uses the principle of light emission absorption by nascent atom cloud from the metals. The analysis has been developed in three stages of the tube heating programs, i.e. drying, ashing and then atomizing element at 3000° C. Since the injected sample is almost completely atomized, the sensitivity of GFAAS is extremely high and this value is covering up the disadvantages of the other analyses. Therefore, the GFAAS analysis is suitable fo ultra-trace analysis of ultra-trace pollutants like heavy metals in environment.
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Jakovljevic, Ksenija, Sanja Djurovic, Mina Antusevic, Nevena Mihailovic, Uros Buzurovic y Gordana Tomovic. "Heavy metal tolerance of Pontechium maculatum (Boraginaceae) from several ultramafic localities in Serbia". Botanica Serbica 43, n.º 1 (2019): 73–83. http://dx.doi.org/10.2298/botserb1901073j.
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Pontechium maculatum, a facultative metallophyte, was collected from four ultramafic localities in Serbia and analysed in terms of micro- and macroelement accumulation. The aim of the study was to reveal trace element profiles and differences in uptake and translocation of heavy metals in populations growing under heavy metal stress. The concentrations of major and trace elements in soil samples (Ca, Mg, Fe, Mn, Ni, Pb, Cr, Zn, Cu, Co, Cd) and in plant tissues (Fe, Mn, Ni, Pb, Cr, Zn, Cu, Co, Cd) are presented. The results of our analysis indicate that P. maculatum efficiently absorbs Zn and Cr, while for most of the other elements accumulation levels fit in the range of values obtained for several other species from ultramafic localities on the Balkan Peninsula.
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Markovic, Jelena, Danijela Joksimovic y Slavka Stankovic. "Trace element concentrations in wild mussels from the coastal area of the southeastern Adriatic, Montenegro". Archives of Biological Sciences 64, n.º 1 (2012): 265–75. http://dx.doi.org/10.2298/abs1201265m.
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The aim of the present investigation was to quantify the levels of trace elements (Zn, Cu, As, Pb, Cd and total Hg) in the Mediterranean mussel, Mytilus galloprovincialis (L.). Based on their levels, the quality of Montenegro seawater for future mussel farming was estimated. The mussel M. galloprovincialis (L.) was collected from four sites in the Montenegrin costal area in the period of two years to determine trace element concentrations and to classify the quality of the coastal water and possible health risks from its consumption. The mean metal concentrations in the mussels ranged from 133.5-205.9 for Zn, 7.50-14.5 for Cu, 4.42-13.3 for As, 4.70-12.9 for Pb, 1.73-2.41 for Cd and 0.07-0.59 for total Hg in mg/kg dry weight. The levels of toxic metals (except for Pb) in the mussels were within the maximum residual levels prescribed by the laws of Montenegro, the EU and the USFDA. In addition, the trace metal concentrations found in the mussels in this study were similar to regional data using this mussel as a biomonitoring agent of seawater quality.
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Li, Xiaoping, Bin Liu, Yu Zhang, Jiwen Wang, Hameed Ullah, Ming Zhou, Liyuan Peng et al. "Spatial Distributions, Sources, Potential Risks of Multi-Trace Metal/Metalloids in Street Dusts from Barbican Downtown Embracing by Xi’an Ancient City Wall (NW, China)". International Journal of Environmental Research and Public Health 16, n.º 16 (20 de agosto de 2019): 2992. http://dx.doi.org/10.3390/ijerph16162992.
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A total of 116 dust samples in downtown within the city wall were collected, and the spatial occurrence, source and health risk status of 19 trace metal/metalloids bound in street dusts (SDs) were systematically investigated. Geochemical maps, associations, risk models and indices were calculated to define levels of distribution, possible natural or anthropogenic sources, ecological and human health risks. It was found that the wide variations of these 19 trace metals would be observed in spatial maps, which indicated strongly anthropogenic activities inputs. Compared to the calculations of the potential ecological risk index of toxic trace metals, Pb (Eri = 20.32) ranked at the level of considerable ecological risk. The non-carcinogenic and carcinogenic risk from most trace metals exposed to children and adults were no significant health risks, except for the non-carcinogenic risk of Cr and As to children, and the carcinogenic risk of Cr to adults. The unacceptable risk locations were observed at traffic conjunctions, which should be given attention. The source apportionment results indicated that the trace metals/metalloids Co, Ga, Nb, As, Ni, and Y, coupled with main elements Al, K, Mg, Ca and Si, would possibly originate from “Soil Re-suspension”, whereas Fe, Cu, Rb, La, Ba, Mn, Ti, Ce and Zr were possibly derived from “Brake Wear”. As regards the Na, no valid assumption was formulated about the presence of this element in brake wear, while Cr, Sr, Zn were possibly associated with “Tire Wear”. Comparatively, V would be suggested as a representative source of fuel consumption, and Pb could possibly belong to “Traffic Pigment”. It was noted that the barbican city, surrounded by the Xi’an Ancient City Wall at 12 m high, would trap the trace metal emissions, and consequently increase the health risk for local residents.
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Tashenov, A. K., A. S. Kabylova, M. V. Frontasyeva, N. M. Omarova y S. V. Morzhukhina. "Assessment of heavy metal and other toxic elements deposition in the Karaganda Region based on moss analysis". BULLETIN of the L.N. Gumilyov Eurasian National University. Chemistry. Geography. Ecology Series 130, n.º 1 (2020): 54–61. http://dx.doi.org/10.32523/2616-6771-2020-130-1-54-61.
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The results on assessing trace element contamination of the environment based on analysis of moss biomonitors collected in Central Kazakhstan. Concentrations of elements were determined by neutron activation analysis and atomic absorption spectrometry in the Joint Institute for Nuclear Research. A total of 39 elements were identified, including heavy metals.
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Fryer, Brian J. y John D. Greenough. "Evidence for mantle heterogeneity from platinum-group-element abundances in Indian Ocean basalts". Canadian Journal of Earth Sciences 29, n.º 11 (1 de noviembre de 1992): 2329–40. http://dx.doi.org/10.1139/e92-181.
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Oceanic-island tholeiitic basalts recovered from four sunken oceanic islands along the Reunion hot-spot trace show trace-element and mineralogical characteristics ranging from typical oceanic-island tholeiites to incompatible-element-depleted tholeiites resembling mid-ocean-ridge basalts. There are also variable degrees of magma evolution at each island. Noble metal (Au, Pd, Pt, Rh, Ru, Ir) abundances tend to decrease with magma evolution and with magma "alkalinity", indicating that the metals behave as compatible elements during crystal fractionation processes and during mantle melting processes. Palladium-to-iridium ratios also decrease with increasing alkalinity. Absolute abundances of elements such as Pd are higher than those in typical mid-ocean-ridge basalts, by factors up to 30, despite many major-element similarities with the latter. Comparison with other types of mafic rocks shows that Pd/Ir ratios increase with decreasing alkalinity in basaltic rocks but plunge to alkali-basalt values in komatiites. A model involving retention of low-melting-point Au, Pd, and Rh in mantle sulphides, which completely dissolve by intermediate percentages of melting, and the high-melting-point metals Ir and Ru in late-melting mantle alloys explains increasing Pd/Ir ratios with decreasing alkalinity (increasing melting percentages) in oceanic basalts and the low Pd/Ir ratios of high-percentage melt komatiites.The high noble metal concentrations in Indian Ocean basalts compared with basalts from many other ocean basins are most easily explained by higher concentrations in their source regions. This may be related to incomplete mixing of a post-core-formation meteoritic component of the upper mantle, or deep mantle plume-derived blebs of core material that either failed to reach the core, during core–mantle differentiation, or were plucked from the core by a convecting lower mantle. The latter is tentatively favoured due to the apparently higher noble metal concentrations in oceanic-island (plume) basalts.
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Yang, Rong, Zeyu Du y Junqia Kong. "Decadal changes and ecological risk assessment of trace and heavy metal elements in soils of a desert oasis, Linze County, China". Soil Research 57, n.º 2 (2019): 178. http://dx.doi.org/10.1071/sr18245.
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This study assesses decadal changes (2005–2015) in the trace and heavy metal element contents of soils from four land use types at a desert oasis and also determines associated ecological and health risks. Concentrations of boron, molybdenum, manganese, zinc, copper, cadmium, lead, and mercury increased significantly over the decade. Farmland ecosystems had higher concentrations of soil trace and heavy metal elements than natural ecosystems, but intercropping with alfalfa tended to reduce concentrations. The environmental pollution assessment indicated that soils were moderately affected by human activities, particularly in farmland ecosystems. The potential degree of ecological risk from all elements was moderate, and in relation to land use this risk decreased in the following order: long-term cultivated farmland>newly reclaimed farmlands with monoculture>newly reclaimed farmlands with intercropping>natural desert grassland. Eight soil heavy metals posed potential non-carcinogenic risks, and dermal contact was the major exposure pathway; however, the carcinogenic risk level from soil was acceptable. These results suggest that agricultural activities increased the concentrations of certain soil trace and heavy metal elements and that adopting appropriate farmland management, such as intercropping with alfalfa, limited this increasing trend.
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Song, Y. y G. Muller. "Biogeochemical cycling of nutrients and trace metals in anoxic freshwater sediments of the Neckar River, Germany". Marine and Freshwater Research 46, n.º 1 (1995): 237. http://dx.doi.org/10.1071/mf9950237.
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Pore-water components (SO42-, Fe2+, Mn2+), including nutrients (NH4+:, NO3-, PO43-), alkalinity and pH were determined at three sites in the Neckar River. Sequential extraction procedures and trace metals in both pore waters and sediments are reported in order to evaluate the mobility of trace metals in contaminated sediments. The results show that the mineralization of organic matter plays an important role in the cycling of nutrients and trace metals. Pore-water profiles (Zn, Cu, Pb, Cd) suggest that the element maximums at the sediment-water interface are caused by the decomposition of biomass. Low concentrations of dissolved Zn, Cu, Pb and Cd in the anoxic sediments can be explained by a sharp decrease of SO42- in pore water concomitant with HS- production. This leads to the formation of highly insoluble metal sulfides. Solubility calculations show that the sediments act as a sink for trace metals with respect to trace metal sulfides. The organic/sulfidic-bound fraction accounts for 64-81% of Cd in the sediment cores, 36-67% of Pb and 51-69% of Cu. In contrast, Cr in pore water increases with depth because of its release from Fe/Mn oxides. NH4+ and PO43- are also released into the pore water owing to the mineralization of organic matter. No significant fluxes of NH4+ and PO43- into overlying water were found because of the existence of an oxic surface layer.
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Huque, Roksana, M. Kamruzzaman Munshi, Afifa Khatun, Mahfuza Islam, Afzal Hossain, Arzina Hossain, Shirin Akter, Jamiul Kabir, Yeasmin Nahar Jolly y Ashraful Islam. "Comparative Study of Raw and Boiled Silver Pomfret Fish from Coastal Area and Retail Market in Relation to Trace Metals and Proximate Composition". International Journal of Food Science 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/826139.
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Trace metals concentration and proximate composition of raw and boiled silver pomfret (Pampus argenteus) from coastal area and retail market were determined to gain the knowledge of the risk and benefits associated with indiscriminate consumption of marine fishes. The effects of cooking (boiling) on trace metal and proximate composition of silver pomfret fish were also investigated. Trace element results were determined by the Energy Dispersive X-ray Fluorescence (EDXRF) Spectrometer wherein fish samples from both areas exceeded the standard limits set by FAO/WHO for manganese, lead, cadmiumm and chromium and boiling has no significant effects on these three metal concentrations. Long-term intake of these contaminated fish samples can pose a health risk to humans who consume them.
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Zaccaroni, Annalisa, Camilla Niccoli, Giulia Andreani, Dino Scaravelli, Maria Ferrante, Antonia Lucisano y Gloria Isani. "Trace metal concentration in wild avian species from Campania, Italy". Open Chemistry 9, n.º 1 (1 de febrero de 2011): 86–93. http://dx.doi.org/10.2478/s11532-010-0119-7.
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AbstractThis study was conducted to determine heavy metals concentrations in tissues of 94 birds belonging to different species from coastal areas of Naples and Salerno (Southern Italy) in order to provide baseline data concerning trace element levels in wild birds living in or close to an area characterized by high anthropogenic impact. Additional aim of this study was to verify if diet influenced metal accumulation, so birds were classified as birds of prey, fish eating birds and insectivorous birds. Kidney was the primary organ for Cd accumulation in all groups considered, Pb was accumulated preferentially in bone, whereas Hg showed high values in liver of fish eating birds. Zn showed the highest mean concentrations, while Cu levels were one order of magnitude less. The variance analysis with respect to feeding habits disclosed only a lower accumulation of Hg in insectivores with respect to the other groups. For all metals, the concentrations measured in tissues should be considered indicative of chronic exposure to low, “background” environmental levels and/or to the presence of low bioavailable metals in the environment. In addition, metal levels were not of toxicological concern, being always well below the toxic thresholds defined for each metal.
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Tutic, Adnan, Srecko Novakovic, Mitar Lutovac, Rade Biocanin, Sonja Ketin y Nusret Omerovic. "The Heavy Metals in Agrosystems and Impact on Health and Quality of Life". Open Access Macedonian Journal of Medical Sciences 3, n.º 2 (3 de junio de 2015): 345–55. http://dx.doi.org/10.3889/oamjms.2015.048.
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The metal is a chemical element that conducts electricity well and heat, and the nonferrous metals builds cations and ionic bonds. Heavy metals include metals whose density is higher than 5 g/cm3. The whole range of the metal is in the form of essential trace elements, essential for a number of functions in the human body, and its deficiency results in a lack of occurrence of a serious symptom. The best examples are anemia lack of iron, lack of chromium in diabetes, growth problems in lack of nickel. Other elements such as lead, cadmium, mercury, arsenic and molybdenum have been shown to exhibit large quantities of toxic effects. The paper examines the problem of heavy metals originating from agriculture on agroecosystems. This group of pollutants is considered the most important cause of degradation of soil quality, surface and groundwater and direct causal adverse effects on human and animal health. In order to complete the environmental monitoring of pollutants, these main categories, origins, and possible negative impacts of the basic principles of preventing their toxic effects were examined.
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Pott, Ute y David H. Turpin. "Changes in atmospheric trace element deposition in the Fraser Valley, B.C., Canada from 1960 to 1993 measured by moss monitoring with Isothecium stoloniferum". Canadian Journal of Botany 74, n.º 8 (1 de agosto de 1996): 1345–53. http://dx.doi.org/10.1139/b96-163.
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Moss monitoring, a common bioindication method, was used to investigate temporal changes of atmospheric trace element deposition since the 1960s in the Fraser Valley, British Columbia. Vancouver, Canada's third largest metropolitan area, is located in the west of the Fraser Valley and has a significant effect on the air quality of the region. Changes in atmospheric deposition of lead, cadmium, chromium, nickel, zinc, and manganese were estimated by analyzing local samples of the common woodland moss Isothecium stoloniferum Brid. collected during three different time periods: 1960–1966, 1975–1980, and 1993. A significant decrease was found for lead, cadmium, chromium, nickel, and zinc, when samples from 1960–1966 were compared with those collected in 1993. The declining metal levels are associated with a change in industrial activity, a reduction in fuel oil combustion for space heating, and abandonment of leaded gasoline. Manganese concentration in the moss samples increased significantly over the past 30 years. This increase might be related to the replacement of the antiknock additive, tetraethyl lead, with methylcyclopentadienyl manganese tricarbonyl. The present study shows how changes in human activity can affect and counterbalance increasing pressure from a fast-growing population in respect to trace element pollution. Keywords: moss monitoring, bioindication, heavy metals, trace elements, Isothecium stoloniferum, air pollution, metal deposition.
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Pastorino, Paolo, Annalisa Zaccaroni, Alberto Doretto, Elisa Falasco, Marina Silvi, Alessandro Dondo, Antonia Concetta Elia, Marino Prearo y Francesca Bona. "Functional Feeding Groups of Aquatic Insects Influence Trace Element Accumulation: Findings for Filterers, Scrapers and Predators from the Po Basin". Biology 9, n.º 9 (14 de septiembre de 2020): 288. http://dx.doi.org/10.3390/biology9090288.
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For this study, we measured the concentrations of 23 trace elements (Al, As, Ba, Bi, Cd, Cr, Co, Cu, Fe, Ga, Hg, In, Li, Mn, Mo, Ni, Pb, Se, Sr, Ti, Tl, V, and Zn) in the whole bodies of three functional feeding groups (FFG) (filterers—Hydropsychidae, scrapers—Heptageniidae, and predators—Odonata) of aquatic insects collected from two sites in the Po basin (Po Settimo and Malone Front, Northwest Italy) to determine: (a) how FFG influence trace element accumulations, (b) if scrapers accumulate higher elements compared to the other FFG, since they graze on periphyton, which represents one of the major sinks of metals, and (c) the potential use of macroinvertebrates to assess the bioavailability of trace elements in freshwater. The hierarchical clustering analysis generated three main groups based on trace element concentrations: the most abundant elements were Fe and Al, followed by Sr, In, Zn, V, Mo, and Cu. Tl was below the limit of detection (LOD) in all FFG. Ga was detected only in scrapers from both sites and Hg only in predators from Po Settimo. The principal component analysis showed that concentrations of Al, As, Bi, Cd, Co, Cr, Ga, Fe, In, Mn, Pb, Ni, and Sr were highest in scrapers, suggesting that trace elements accumulate from the ingestion of epilithic periphyton (biofilm). Odonata (predators) accumulate certain elements (Ba, Hg, Li, Se, V, Ti, and Zn) in higher concentrations by food ingestion composed of different aquatic organisms. Differently, Cu and Mo concentrations were the highest in filterers due to their bioavailability in the water column. Non-metric multidimensional scaling clearly differentiated the FFG based on their ability to accumulate trace elements. The findings from this study represent an important step toward the definition of an innovative approach based on trace element accumulation by macroinvertebrates.
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Antcibor, I., A. Eschenbach, S. Zubrzycki, L. Kutzbach, D. Bolshiyanov y E. M. Pfeiffer. "Trace metal distribution in pristine permafrost-affected soils of the Lena River delta and its hinterland, northern Siberia, Russia". Biogeosciences 11, n.º 1 (2 de enero de 2014): 1–15. http://dx.doi.org/10.5194/bg-11-1-2014.
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Abstract. Soils are an important compartment of ecosystems and have the ability to buffer and immobilize substances of natural and anthropogenic origin to prevent their movement to other environment compartments. Predicted climatic changes together with other anthropogenic influences on Arctic terrestrial environments may affect biogeochemical processes enhancing leaching and migration of trace elements in permafrost-affected soils. This is especially important since Arctic ecosystems are considered to be highly sensitive to climatic changes as well as to chemical contamination. This study characterises background levels of trace metals in permafrost-affected soils of the Lena River delta and its hinterland in northern Siberia (73.5–69.5° N), representing a remote region far from evident anthropogenic trace metal sources. Investigations on the element content of iron (Fe), arsenic (As), manganese (Mn), zinc (Zn), nickel (Ni), copper (Cu), lead (Pb), cadmium (Cd), cobalt (Co), and mercury (Hg) in different soil types developed in different geological parent materials have been carried out. The highest median concentrations of Fe and Mn were observed in soils belonging to ice-rich permafrost sediments formed during the Pleistocene (ice-complex) while the highest median values of Ni, Pb and Zn were found in soils of both the ice-complex and the Holocene estuarine terrace of the Lena River delta region, as well as in the southernmost study unit of the hinterland area. Detailed observations of trace metal distribution on the micro scale showed that organic matter content, soil texture and iron-oxide contents influenced by cryogenic processes, temperature, and hydrological regimes are the most important factors determining the metal abundance in permafrost-affected soils. The observed range of trace element background concentrations was similar to trace metal levels reported for other pristine northern areas.
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GRIME, GEOFFREY W., EVA PÅLSGÅRD, ELSPETH F. GARMAN, MARTA UGARTE, DAVID POTTAGE y PAUL WYETH. "RECENT BIOMEDICAL APPLICATIONS OF THE OXFORD SCANNING PROTON MICROPROBE". International Journal of PIXE 09, n.º 03n04 (enero de 1999): 199–216. http://dx.doi.org/10.1142/s0129083599000309.
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The Oxford Scanning Proton Microprobe continues to be used in the field of trace element measurement in biological systems, exploiting the unique advantages of sensitive, quantitative trace element analysis using PIXE, high spatial resolution and the long penetrating power of MeV protons. This paper outlines a number of recent applications which highlight these advantages. These include: (a) Analysing the distribution of metals in the pupae of leaf-cutting ants to determine the storage sites and transport mechanism of metals used to harden the edges of the mandibles. (b) A study of the distribution of zinc in the retina of rats to determine the role of zinc in light and dark adaptation of the eye. (c) The analysis of crystals of proteins and other large organic molecules prepared for structure determination using x-ray diffraction. These often contain metal atoms, and the identity and concentration of the metal is an important diagnostic for determining the nature of the protein and the quality of the crystallisation. The crystals are normally small (~100μm) and so microPIXE is being used to characterise them. This technique has wide ranging applications, including qualitative and quantitative identification of metals in reaction centres, in active sites and in metal binding proteins, and of DNA or RNA bound to proteins.
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Adeaga, Olusegun, Gil Mahe, Claudine Dieulin, Francoise Elbaz-Poulichet, Nathalie Rouche, Jean-Luc Seidel y Eric Servat. "Quality of water resources in the Niger basin and in the region of Lagos (Nigeria)". Bulletin of Geography. Physical Geography Series 13, n.º 1 (1 de diciembre de 2017): 51–60. http://dx.doi.org/10.1515/bgeo-2017-0013.
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AbstractWater quality studies in Nigeria are usually conducted at local scales and limited to a restricted number of chemical contaminants, while reliable data on trace metal concentrations (including arsenic) are relatively scarce. This study focuses on the quality of available renewable water resources in terms of major ion and trace element concentrations at selected sampling locations in the Lower River Niger basin and part of the Lagos region. A screening of water contamination by arsenic and heavy metals was carried out through water sampling at selected locations using in situ measurement and laboratory testing to estimate heavy metal concentrations and water type. The analysis reveals moderate trace element contamination of the water resources, with the exception of Pb, while Mn and, to a lesser extent, Al exceeded WHO quality standards, but the Arsenic concentrations are within drinking water quality standards and are safe for consumption and irrigation, while the water type is Bicarbonate.
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Sim, Siong Fong, Teck Yee Ling, Lee Nyanti, Terri Zhuan Ean Lee, Nurul Aida Lu Mohd Irwan Lu y Tomy Bakeh. "Distribution of Major and Trace Elements in a Tropical Hydroelectric Reservoir in Sarawak, Malaysia". International Scholarly Research Notices 2014 (21 de septiembre de 2014): 1–12. http://dx.doi.org/10.1155/2014/870187.
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This paper reports the metals content in water, sediment, macroalgae, aquatic plant, and fish of Batang Ai Hydroelectric Reservoir in Sarawak, Malaysia. The samples were acid digested and subjected to atomic absorption spectrometry analysis for Na, K, Mn, Cr, Ni, Zn, Mg, Fe, Sn, Al, Ca, As, Se, and Hg. The total Hg content was analysed on the mercury analyser. Results showed that metals in water, sediment, macroalgae, aquatic plant, and fish are distinguishable, with sediment and biota samples more susceptible to metal accumulation. The distributions of heavy metals in water specifically Se, Sn, and As could have associated with the input of fish feed, boating, and construction activities. The accumulation of heavy metals in sediment, macroalgae, and aquatic plant on the other hand might be largely influenced by the redox conditions in the aquatic environment. According to the contamination factor and the geoaccumulation index, sediment in Batang Ai Reservoir possesses low risk of contamination. The average metal contents in sediment and river water are consistently lower than the literature values reported and well below the limit of various guidelines. For fishes, trace element Hg was detected; however, the concentration was below the permissible level suggested by the Food and Agriculture Organization.
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van de Flierdt, Tina, Alexander M. Griffiths, Myriam Lambelet, Susan H. Little, Torben Stichel y David J. Wilson. "Neodymium in the oceans: a global database, a regional comparison and implications for palaeoceanographic research". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, n.º 2081 (28 de noviembre de 2016): 20150293. http://dx.doi.org/10.1098/rsta.2015.0293.
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The neodymium (Nd) isotopic composition of seawater has been used extensively to reconstruct ocean circulation on a variety of time scales. However, dissolved neodymium concentrations and isotopes do not always behave conservatively, and quantitative deconvolution of this non-conservative component can be used to detect trace metal inputs and isotopic exchange at ocean–sediment interfaces. In order to facilitate such comparisons for historical datasets, we here provide an extended global database for Nd isotopes and concentrations in the context of hydrography and nutrients. Since 2010, combined datasets for a large range of trace elements and isotopes are collected on international GEOTRACES section cruises, alongside classical nutrient and hydrography measurements. Here, we take a first step towards exploiting these datasets by comparing high-resolution Nd sections for the western and eastern North Atlantic in the context of hydrography, nutrients and aluminium (Al) concentrations. Evaluating those data in tracer–tracer space reveals that North Atlantic seawater Nd isotopes and concentrations generally follow the patterns of advection, as do Al concentrations. Deviations from water mass mixing are observed locally, associated with the addition or removal of trace metals in benthic nepheloid layers, exchange with ocean margins (i.e. boundary exchange) and/or exchange with particulate phases (i.e. reversible scavenging). We emphasize that the complexity of some of the new datasets cautions against a quantitative interpretation of individual palaeo Nd isotope records, and indicates the importance of spatial reconstructions for a more balanced approach to deciphering past ocean changes. This article is part of the themed issue ‘Biological and climatic impacts of ocean trace element chemistry’.
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Cory-Slechta, Deborah, Marissa Sobolewski y Günter Oberdörster. "Air Pollution-Related Brain Metal Dyshomeostasis as a Potential Risk Factor for Neurodevelopmental Disorders and Neurodegenerative Diseases". Atmosphere 11, n.º 10 (14 de octubre de 2020): 1098. http://dx.doi.org/10.3390/atmos11101098.
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Increasing evidence links air pollution (AP) exposure to effects on the central nervous system structure and function. Particulate matter AP, especially the ultrafine (nanoparticle) components, can carry numerous metal and trace element contaminants that can reach the brain in utero and after birth. Excess brain exposure to either essential or non-essential elements can result in brain dyshomeostasis, which has been implicated in both neurodevelopmental disorders (NDDs; autism spectrum disorder, schizophrenia, and attention deficit hyperactivity disorder) and neurodegenerative diseases (NDGDs; Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, and amyotrophic lateral sclerosis). This review summarizes the current understanding of the extent to which the inhalational or intranasal instillation of metals reproduces in vivo the shared features of NDDs and NDGDs, including enlarged lateral ventricles, alterations in myelination, glutamatergic dysfunction, neuronal cell death, inflammation, microglial activation, oxidative stress, mitochondrial dysfunction, altered social behaviors, cognitive dysfunction, and impulsivity. Although evidence is limited to date, neuronal cell death, oxidative stress, and mitochondrial dysfunction are reproduced by numerous metals. Understanding the specific contribution of metals/trace elements to this neurotoxicity can guide the development of more realistic animal exposure models of human AP exposure and consequently lead to a more meaningful approach to mechanistic studies, potential intervention strategies, and regulatory requirements.
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Bermudez, Gonzalo M. A., Raquel Jasan, Rita Plá y María L. Pignata. "Heavy metals and trace elements in atmospheric fall-out: Their relationship with topsoil and wheat element composition". Journal of Hazardous Materials 213-214 (abril de 2012): 447–56. http://dx.doi.org/10.1016/j.jhazmat.2012.02.023.
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Saçmacı, Şerife y Şenol Kartal. "A Multi-Element Ion-Pair Extraction for Trace Metals Determination in Environmental Samples". CLEAN - Soil, Air, Water 39, n.º 6 (20 de mayo de 2011): 577–83. http://dx.doi.org/10.1002/clen.201000210.
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Deng, Junjing, David J. Vine, Si Chen, Youssef S. G. Nashed, Qiaoling Jin, Nicholas W. Phillips, Tom Peterka, Rob Ross, Stefan Vogt y Chris J. Jacobsen. "Simultaneous cryo X-ray ptychographic and fluorescence microscopy of green algae". Proceedings of the National Academy of Sciences 112, n.º 8 (9 de febrero de 2015): 2314–19. http://dx.doi.org/10.1073/pnas.1413003112.
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Trace metals play important roles in normal and in disease-causing biological functions. X-ray fluorescence microscopy reveals trace elements with no dependence on binding affinities (unlike with visible light fluorophores) and with improved sensitivity relative to electron probes. However, X-ray fluorescence is not very sensitive for showing the light elements that comprise the majority of cellular material. Here we show that X-ray ptychography can be combined with fluorescence to image both cellular structure and trace element distribution in frozen-hydrated cells at cryogenic temperatures, with high structural and chemical fidelity. Ptychographic reconstruction algorithms deliver phase and absorption contrast images at a resolution beyond that of the illuminating lens or beam size. Using 5.2-keV X-rays, we have obtained sub–30-nm resolution structural images and ∼90-nm–resolution fluorescence images of several elements in frozen-hydrated green algae. This combined approach offers a way to study the role of trace elements in their structural context.