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Metal Accumulation (metal + accumulation)
Kinds of Metal Accumulation Selected AbstractsSeedling Growth and Heavy Metal Accumulation of Candidate Woody Species for Revegetating Korean Mine SpoilsRESTORATION ECOLOGY, Issue 4 2008Kyung Won Seo Abstract Selecting plant species that can overcome harsh soil and microclimatic conditions and speed the recovery of degraded minelands remains a worldwide restoration challenge. This study evaluated the potential of three woody species and various organic and inorganic fertilization treatments for revegetating abandoned metalliferous mines in Korea. We compared survival, growth, and heavy metal uptake of species common to Korean minelands in two spoil types and a reference forest soil. Substrate type and fertilization both influenced seedling growth and metal concentrations substantially, but they had little effect on seedling survival. Fertilization increased the growth of all three species when grown in mine spoils but influenced the growth of seedlings grown in forest soil only marginally. Initial seedling survival and growth indicate that the study species can tolerate the heavy metal concentrations and other soil constraints of metalliferous spoil types. We estimate that plants can stabilize 2,22% of various heavy metals contained in spoil materials into plant biomass during 20 years of plantation growth. Combined with the erosion control and site amelioration benefits of mineland reforestation, stabilization of heavy metals in forest biomass justifies this treatment on abandoned Korean metalliferous mines. [source] Investigation of histopathological and cytogenetic effects on Lepomis gibbosus (Pisces: Perciformes) in the Çine stream (Ayd,n/Turkey) with determination of water pollutionENVIRONMENTAL TOXICOLOGY, Issue 6 2005Yücel Ba, lu Koca Abstract Water quality and the distribution of some heavy metals in three different organs of Lepomis gibbosus from the Çine Stream were studied. Also, histopathological changes in gill, liver, and muscle tissue were examined at light microscopical level. Micronucleus (MN) formation in fish erytrocytes, as an indicator of chromosomal damage, has been increasingly used to detect the genotoxic potential of environmental contaminants. The frequency of MN was examined from samples of fish from the Çine Stream and a control group. MN frequency was higher in fish samples caught from the Çine Stream than that in the control group. The chemicals ammonia, nitrite, nitrate, orthophosphate, and sulphate were determined as parameters that possibly affect the gill, liver, and muscle morphology. Zn was the most accumulated metal in tissues as well as in water. Maximum metal accumulation occured in both liver and gills. For histopathological examinations, samples of gills, liver, and muscle tissues of L. gibbosus were studied by using light microscopy. In this study, a significant decrease in mean length of primary and secondary lamellae were observed. Moreover, cellular proliferation developed with secondary lamellae fusion, ballooning degenerations or club deformation of secondary lamellae, as well as distribution of necrotic, hyperplastic and clavate secondary lamellae. In the liver, altered staining, swollen and ruptured parenchymal cells, loss of cord structure, reduce of glycogen in hepatocytes, and vacuolar structure filled with cellular debris and many dark particles were seen. In muscle tissue, focal necrosis, cellular dissolution, and a decline or loss of striatation in muscle fibres were found. İ 2005 Wiley Periodicals, Inc. Environ Toxicol 20: 560,571, 2005. [source] Sponges as biomonitors of heavy metals in spatial and temporal surveys in northwestern Mediterranean: Multispecies comparison,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2007Emma Cebrian Abstract Contamination by heavy metals has increased drastically in the coastal Mediterranean during the last 20 years. A comparative study on metal bioaccumulation by four widespread sponge species (Crambe crambe, Chondrosia reniformis, Phorbas tenacior, and Dysidea avara) has been performed to select the most suitable species for metal monitoring. Copper bioaccumulation fits an accumulation strategy while Pb concentration seems to be regulated in most sponges. Crambe crambe was the only studied species that bioaccumulated Pb and Cu as a function of the available metal, proving its suitability for monitoring purposes. Then, we examined its effectiveness as a bioindicator at large spatial and temporal scales, comparing metal accumulation in this species and in sediments. Crambe crambe provided accurate information on the background levels of metals in the area at both spatial and temporal scales, and furthermore it reflected seasonal fluctuations of the bioavailable metals, which would be impossible to assess by means of a sediment survey. [source] Comparison of Cd, Cu, and Zn toxic effects on four marine phytoplankton by pulse-amplitude-modulated fluorometryENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2005Ai-Jun Miao Abstract The toxic effects of Cd, Cu, and Zn on four different marine phytoplankton, Dunaliella tertiolecta, Prorocentrum minimum, Synechococcus sp., and Thalassiosira weissflogii, were examined by comparing the cell-specific growth rate, pulse-amplitude-modulated (PAM) parameters (maximum photosystem II quantum yield ,M and operational quantum yield ,'M), chlorophyll a content, and cellular metal concentration, over a 96-h period. The calculated no-observed-effect concentration (NOEC) based on both cell-specific growth rate and two PAM parameters (,M and ,'M) were mostly identical. Thus, these PAM parameters and cell-specific growth rate were comparable in their sensitivities as the biomarkers for trace metal toxicity to marine phytoplankton. The cyanobacteria Synechococcus sp. was the most sensitive species among the four algal species tested because of its higher cell surface to volume ratio. The toxicity of the three tested metals followed the order of Cd > Cu > Zn based on the cellular metal concentration of the four algae at the NOEC. The cellular metal bioaccumulation followed the same Freundlich isotherm for each metal regardless of the algal species, indicating that the metal accumulation was a nonmetabolic process under high ambient metal concentrations and that the cell surface metal binding was comparable among the different species. For all the algae examined in our study, the bioaccumulation potentials of Cu and Zn were similar to each other, while the Cd bioaccumulation was much lower under environmentally realistic metal concentration. [source] Biofilm formation by algae as a mechanism for surviving on mine tailingsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2005J. Viridiana García-Meza Abstract Photosynthetic biofilms successfully colonize the sediments of a mine tailings reservoir (Guanajuato, Mexico) despite the high metal concentrations that are present. To elucidate the mechanisms of biofilm survival despite metal ores, experiments were performed to evaluate the response of seminatural biofilms to Cu, Zn, and a combination of both metals at concentrations observed in the field. The biofilms were composed mostly of the chlorophyte Chlorococcum sp. and the cyanobacterium Phormidium sp., and their response to the two added metals was described by measurements of extracellular polymeric substances (EPS) and in vivo fluorescence. The photosynthetic efficiency and the minimal chlorophyll fluorescence of dark-adapted cells were measured by multiwavelength pulse amplitude,modulated fluorometry. The photosynthetic efficiency of light-adapted cells (,PSII) also was measured. Metal exposure increased the EPS production of biofilms, as visualized with confocal laser-scanning microscopy. Extracellular polymeric substances enhanced the extracellular metal accumulation from the first day of metal exposure. Metals provoked changes in the relative abundance of the dominant taxa because of a species-specific response to the metals when added individually. Metals affected the ,psii less than the total biomass, suggesting ongoing activity of the surviving biofilms. Survival of individual biofilm photosynthetic cells was found to resume from the embedding in the mucilaginous structure, which immobilizes the metals extracellularly. The survival of biofilms under mixed-metal exposure has practical applications in the remediation of mine tailings. [source] Field contamination of the starfish Asterias rubens by metals.ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2003Part 1: Short-, long-term accumulation along a pollution gradient Abstract The accumulation of Cd, Pb, Zn, and Cu in the starfish Asterias rubens was studied in a Norwegian fjord characterized by a gradient of metal pollution in the sediments, ranging from very high metal concentrations at its head to much lower levels at its opening. The concentrations of metals in starfish from natural populations along the gradient (long-term accumulation) and in starfish that were transferred up the gradient (short-term accumulation) were compared. At long-term, Cd and Pb accumulations by starfish living at normal salinity (30,) were related to the level of contamination of of the environment while Cu and, to a lesser extent, Zn accumulations appeared strictly controlled. At short-term, Pb was accumulated steadily, Cd and Zn were accumulated transiently in the pyloric caeca (fast compartment), and Cu was not accumulated at all. Depuration experiments (transfer down the gradient) showed that Cd and Pb were efficiently eliminated from the pyloric caeca but not from the body wall (slow compartment). It is concluded that Pb is chronically accumulated, without apparent control, Cd is subjected to a regulating mechanism in the pyloric caeca which is overwhelmed over the long-term; Zn is tightly controlled in the pyloric caeca and Cu in both pyloric caeca and body wall. A distinct color variety of starfish is restricted to the low salinity (22-26,) superficial water layer. This variety showed a different pattern of metal accumulation over the long-term. This pattern is attributed to the particular hydrological conditions prevailing in this upper layer. [source] Influence of salinity on lead and cadmium accumulation by the salt cedar (Tamarix smyrnensis Bunge)JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 6 2009Eleni Manousaki Abstract BACKGROUND: The removal of heavy metals from polluted soils through the use of suitable plants has attracted much interest over recent decades. In this study Tamarix smyrnensis Bunge has been investigated for the characterization of its metal tolerance and ability to accumulate Pb and Cd, in order to evaluate its effectiveness as a cleanup tool for phytoextraction applications. For this purpose, two hydroponic experiments were performed, one with lead at concentration 100 ppm and a second with cadmium at concentration 5 ppm and at three different salt concentrations (0, 100, 200 mmol L,1 NaCl). RESULTS: The experimental results showed that Pb and Cd accumulation in shoots ranged from 150,270 ppm and 7.5,42 ppm, respectively, and salinity was found to increase metal accumulation in shoots. However, the presence of high metal and salt concentrations affected negatively the health and finally the survival of the plants. CONCLUSION:T. smyrnensis is neither a Pb nor a Cd hyperaccumulator; however, metal accumulation levels in shoots considered together with its high biomass production suggest that it could be used for phytoextraction applications. Furthermore, salinity has a positive influence on Pb and Cd accumulation in harvestable parts of the plant when it remains in low concentrations. Copyright İ 2009 Society of Chemical Industry [source] A high-throughput determination of metal concentrations in whole intact Arabidopsis thaliana seeds using synchrotron-based X-ray fluorescence spectroscopyJOURNAL OF SYNCHROTRON RADIATION, Issue 4 2006Lester W. Young The identification of genes involved in metal metabolism in plants requires the `screening' of thousands of genetic variants. While inductively coupled plasma mass-spectroscopy has been used to identify variants with an altered total metal concentration, a more convenient high-throughput technique capable of examining individual seeds (or other tissues) would be useful. Here, the high brightness of synchrotron radiation has been utilised to examine relative metal concentrations in seeds of the genetically well characterised plant Arabidopsis thaliana. The relative concentrations of Mn, Fe, Ni, Cu and Zn in individual seeds were determined using a 500,µm × 500,µm beam. Metal concentrations were normally distributed, except where metal-containing dust contaminated the samples. Neither seed orientation nor genetic background (from three `wild type' variants with different genetic lineages) had a significant affect on the Zn-normalised metal concentration. No advantages, such as the observation of tissue-specific metal accumulation, were obtained by using a 50,µm × 50,µm beam. A high-throughput proof-of-concept experiment was demonstrated that could be used to screen libraries of genetic variants for individuals with altered metal concentrations. Further work is required to standardise the technique before screening of libraries is possible. [source] Redox active iron accumulation in aceruloplasminemiaNEUROPATHOLOGY, Issue 5 2008Luis F. Gonzalez-Cuyar Aceruloplasminemia is an autosomal recessive disorder characterized by a ceruloplasmin gene mutation and defective or absent ceruloplasmin function. Because ceruloplasmin functions in iron transport and storage, aceruloplasminemia leads to excessive iron accumulation systemically and within the CNS. The type and form of iron deposited is unclear and while oxidative stress was hypothesized as a potential mechanism of cytotoxicity in this disorder, direct evidence linking oxidative stress to the underlying genetic defect has not been provided. To address these issues, we studied autopsy brain tissue from two subjects with genetically confirmed aceruloplasminemia using an assay developed in our laboratory for redox-active iron assessment. We found iron deposited in perivascular areas, localizing to terminal astrocytic processes and further showed that this iron was redox active. These data are consistent with the concept that oxidative stress, driven by heavy metal accumulation, represents the primary cellular cytotoxic process, accounting for neuronal damage in affected brain regions. As such, aceruloplasminemia is an excellent model of transition metal-driven oxidative stress and neurodegeneration. [source] The dilemma of controlling heavy metal accumulation in plantsNEW PHYTOLOGIST, Issue 1 2009Ute Kraemer No abstract is available for this article. [source] Increased cysteine availability is essential for cadmium tolerance and accumulation in Arabidopsis thalianaPLANT BIOTECHNOLOGY JOURNAL, Issue 6 2004José R. Domínguez-Solís Summary Employing genetic transformation using an Atcys-3A cDNA construct expressing the cytosolic O -acetylserine(thiol)lyase (OASTL), we obtained two Arabidopsis lines with different capabilities for supplying cysteine under metal stress conditions. Lines 1-2 and 10-10, grown under standard conditions, showed similar levels of cysteine and glutathione (GSH) to those of the wild-type. However, in the presence of cadmium, line 10-10 showed significantly higher levels. The increased thiol content allowed line 10-10 to survive under severe heavy metal stress conditions (up to 400 µm of cadmium in the growth medium), and resulted in an accumulation of cadmium in the leaves to a level similar to that of metal hyperaccumulator plants. Investigation of the epidermal leaf surface clearly showed that most of the cadmium had accumulated in the trichomes. Furthermore, line 10-10 was able to accumulate more cadmium in its trichomes than the wild-type, whereas line 1-2 showed a reduced capacity for cadmium accumulation. Our results suggest that an increased rate of cysteine biosynthesis is responsible for the enhanced cadmium tolerance and accumulation in trichome leaves. Thus, molecular engineering of the cysteine biosynthesis pathway, together with modification of the number of leaf trichomes, may have considerable potential in increasing heavy metal accumulation for phytoremediation purposes. [source] Proteomic analysis of Arabidopsis halleri shoots in response to the heavy metals cadmium and zinc and rhizosphere microorganismsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 21 2009Silvia Farinati Abstract Arabidopsis halleri has the rare ability to colonize heavy metal-polluted sites and is an emerging model for research on adaptation and metal hyperaccumulation. The aim of this study was to analyze the effect of plant,microbe interaction on the accumulation of cadmium (Cd) and zinc (Zn) in shoots of an ecotype of A. halleri grown in heavy metal-contaminated soil and to compare the shoot proteome of plants grown solely in the presence of Cd and Zn or in the presence of these two metals and the autochthonous soil rhizosphere-derived microorganisms. The results of this analysis emphasized the role of plant,microbe interaction in shoot metal accumulation. Differences in protein expression pattern, identified by a proteomic approach involving 2-DE and MS, indicated a general upregulation of photosynthesis-related proteins in plants exposed to metals and to metals plus microorganisms, suggesting that metal accumulation in shoots is an energy-demanding process. The analysis also showed that proteins involved in plant defense mechanisms were downregulated indicating that heavy metals accumulation in leaves supplies a protection system and highlights a cross-talk between heavy metal signaling and defense signaling. [source] Multivariate analysis of protein profiles of metal hyperaccumulator Thlaspi caerulescens accessionsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 12 2006Marjo H. Tuomainen Abstract Thlaspi caerulescens is increasingly acknowledged as one of the best models for studying metal hyperaccumulation in plants. In order to study the mechanisms underlying metal hyperaccumulation, we used proteomic profiling to identify differences in protein intensities among three T.,caerulescens accessions with pronounced differences in tolerance, uptake and root to shoot translocation of Zn and Cd. Proteins were separated using two-dimensional electrophoresis and stained with SYPRO Orange. Intensity values and quality scores were obtained for each spot by using PDQuest software. Principal component analysis was used to test the separation of the protein profiles of the three plant accessions at various metal exposures, and to detect groups of proteins responsible for the differences. Spot sets representing individual proteins were analysed with the analysis of variance and non-parametric Kruskal-Wallis test. Clearest differences were seen among the Thlaspi accessions, while the effects of metal exposures were less pronounced. The 48,tentatively identified spots represent core metabolic functions (e.g. photosynthesis, nitrogen assimilation, carbohydrate metabolism) as well as putative signalling and regulatory functions. The possible roles of some of the proteins in heavy metal accumulation and tolerance are discussed. [source] Multiple Sources of Metals of Mineralization in Lower Cambrian Black Shales of South China: Evidence from Geochemical and Petrographic StudyRESOURCE GEOLOGY, Issue 1 2008Jan Pa Abstract Black shales of the Lower Cambrian Niutitang Formation in southern China (Huangjiawan mine, Zunyi region, northern part of the Guizhou Province) host regionally distributed stratiform polymetallic Ni-Mo-platinum group elements (PGE)-Au phosphate- and sulfide-rich ores. These are confined to a ,0.2-m thick ore horizon composed of mineralized bodies of algal onkolites, phosphate nodules, and sulfide and shale clasts in a mineralized phosphate- and organic matter-rich matrix. Compared to footwall and hanging wall shales, the ore bed is strongly enriched in Ni (up to 100-fold), As (up to 97-fold), Mo (up to 95-fold), Sb (up to 67-fold), Rh (up to 49-fold), Cu (up to 37-fold), Pd (up to 33-fold), Ru (up to 24-fold), Zn (up to 23-fold), Pt (up to 21-fold), Ir (up to 15-fold), Co (up to 14-fold), and Pb (up to 13-fold). Even footwall and hanging wall black shales are significantly enriched by Mo (21-fold) and Ni (12-fold) but depleted in Cr in comparison to average Cambrian black shale. Organic matter is represented by separate accumulations dispersed in the rock matrix or as biotic bitumen droplets and veinlets in ore clasts. Similar organic carbon (Corg) values in an ore bed and enclosing footwall and hanging wall shales of little mineralization indicate that metal accumulation was not controlled only by biogenic productivity and organic matter accumulation rate. Evaporitic conditions during sedimentation of the basal part of the Niutitang Formation were documented by an occurrence of preserved Ni-, V-, Cr-, and Cu-enriched phosphate-rich hardground with halite and anhydrite pseudomorphs on the paleosurface of the underlying Neoproterozoic carbonates. Neoproterozoic black shales of the Doushantuo Formation are characterized by increased metal concentrations. Comparison of metal abundances in both hardground and Doushantuo black shales indicate that black shales could have become a source of metal-rich hardground during weathering. The polymetallic Ni-Mo-PGE sulfide-rich ore bed is interpreted to represent a remnant of shallow-water hardground horizon rich in metals, which originated in a sediment-starved, semi-restricted, seawater environment. During the Early Cambrian transgression an influx of fresh seawater and intensive evaporation, together with the hydrothermal enrichment of seawater in a semi-restricted basin, resulted in the formation of dense metalliferous brines; co-precipitation of metals together with phosphates and sulfides occurred at or above the oxic,anoxic sediment interface. Metal-enriched hardground was disintegrated by the action of waves or bottom currents and deposited in a deeper part of the anoxic basin. Contemporaneously with the formation of a polymetallic Ni-Mo-PGE-Au sulfide ore bed, economic sedimentary exhalative (SEDEX)-type barite deposits were forming in a stratigraphically and geotectonically similar setting. The results of geochemical study at the Shang Gongtang SEDEX-type Ba deposit indicate that concentrations of Ag, As, Cr, Cu, Fe, Mn, Ni, Pb, Sb, V, Zn and other metals decrease from top of the barite body toward the hanging wall black shale. Lower Cambrian black shales of the Niutitang Formation above the barite body also display similar element abundances as Neoproterozoic black shales of the Doushantuo Formation, developed in the footwall of the barite body. But the geochemical composition of the sulfide layer is different from the Ni-Mo ore bed, showing only elevated Pb, Cu, Ni and Mo values. It is suggested that hydrothermal brines at Shang Gongtang might have leached metals from footwall Neoproterozoic sequences and became, after mixing with normal seawater, an additional source of Ag, Cr, Cu, Pb, Sb, Zn, Ni, PGE, V and other metals. [source] Level of trace elements in Pteridophytes growing on serpentine and metalliferous soilsJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 6 2007Laura Cornara Abstract A screening of Pteridophytes growing on serpentine and metalliferous soils in Northern Italy was carried out to assess the ability of these plants to tolerate or accumulate trace elements of toxicological interest. Few data are available on metal tolerance/accumulation of terrestrial ferns growing in the Mediterranean region, and several species presented here have never been investigated for this purpose. The trace-element composition (As, Cd, Cr, Cu, Fe, Ni, Pb, Zn) and P content of aerial parts of plants (12 fern and 2 horsetail species) and of their associated soils were measured. An analysis of the relationship between element concentrations in soil and in shoot revealed a significant correlation only for Zn (p < 0.05). Hierarchical cluster analysis based on element concentrations in plant aerial parts showed two outliers, viz. Equisetum ramosissimum Desf., showing the highest levels of Cr, Fe, Cu, Ni, and As, and Nephrolepis cordifolia C. Presl., showing the highest Pb value. The bioaccumulation factor exceeded 1 only for Cd in two species, Athyrium filix-femina and Dryopteris filix-mas. However, also in these cases the corresponding values of the metal in the shoots were below the thresholds for hyperaccumulators. The examined Pteridophytes seem to have developed their adaptation prevalently through mechanisms of tolerance based on metal exclusion. None of these plant species seem suitable for phytoextraction, but N. cordifolia, Pteridium aquilinum ssp. aquilinum, and E. ramosissimum have potential to be used for stabilization and restoration of soils rich in heavy metals. [source] Proteomic analysis of Arabidopsis halleri shoots in response to the heavy metals cadmium and zinc and rhizosphere microorganismsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 21 2009Silvia Farinati Abstract Arabidopsis halleri has the rare ability to colonize heavy metal-polluted sites and is an emerging model for research on adaptation and metal hyperaccumulation. The aim of this study was to analyze the effect of plant,microbe interaction on the accumulation of cadmium (Cd) and zinc (Zn) in shoots of an ecotype of A. halleri grown in heavy metal-contaminated soil and to compare the shoot proteome of plants grown solely in the presence of Cd and Zn or in the presence of these two metals and the autochthonous soil rhizosphere-derived microorganisms. The results of this analysis emphasized the role of plant,microbe interaction in shoot metal accumulation. Differences in protein expression pattern, identified by a proteomic approach involving 2-DE and MS, indicated a general upregulation of photosynthesis-related proteins in plants exposed to metals and to metals plus microorganisms, suggesting that metal accumulation in shoots is an energy-demanding process. The analysis also showed that proteins involved in plant defense mechanisms were downregulated indicating that heavy metals accumulation in leaves supplies a protection system and highlights a cross-talk between heavy metal signaling and defense signaling. [source] | ||||||||||||||||