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Sample records for mycorrhiza enhanced arsenic

  1. Arbuscular mycorrhiza enhanced arsenic resistance of both white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.) plants in an arsenic-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Dong Yan; Zhu Yongguan [Department of Soil Environmental Science, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Smith, F. Andrew [Soil and Land Systems, School of Earth and Environmental Sciences, Waite Campus, University of Adelaide, Adelaide, SA 5005 (Australia); Wang Youshan [Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry, Beijing 100089 (China); Chen Baodong [Department of Soil Environmental Science, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China)], E-mail: bdchen@rcees.ac.cn

    2008-09-15

    In a compartmented cultivation system, white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.), with their roots freely intermingled, or separated by 37 {mu}m nylon mesh or plastic board, were grown together in an arsenic (As) contaminated soil. The influence of AM inoculation on plant growth, As uptake, phosphorus (P) nutrition, and plant competitions were investigated. Results showed that both plant species highly depended on mycorrhizas for surviving the As contamination. Mycorrhizal inoculation substantially improved plant P nutrition, and in contrast markedly decreased root to shoot As translocation and shoot As concentrations. It also showed that mycorrhizas affected the competition between the two co-existing plant species, preferentially benefiting the clover plants in term of nutrient acquisition and biomass production. Based on the present study, the role of AM fungi in plant adaptation to As contamination, and their potential use for ecological restoration of As contaminated soils are discussed. - Both white clover and ryegrass highly depend on the mycorrhizal associations for surviving heavy arsenic contamination.

  2. Arbuscular mycorrhiza enhanced arsenic resistance of both white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.) plants in an arsenic-contaminated soil

    International Nuclear Information System (INIS)

    Dong Yan; Zhu Yongguan; Smith, F. Andrew; Wang Youshan; Chen Baodong

    2008-01-01

    In a compartmented cultivation system, white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.), with their roots freely intermingled, or separated by 37 μm nylon mesh or plastic board, were grown together in an arsenic (As) contaminated soil. The influence of AM inoculation on plant growth, As uptake, phosphorus (P) nutrition, and plant competitions were investigated. Results showed that both plant species highly depended on mycorrhizas for surviving the As contamination. Mycorrhizal inoculation substantially improved plant P nutrition, and in contrast markedly decreased root to shoot As translocation and shoot As concentrations. It also showed that mycorrhizas affected the competition between the two co-existing plant species, preferentially benefiting the clover plants in term of nutrient acquisition and biomass production. Based on the present study, the role of AM fungi in plant adaptation to As contamination, and their potential use for ecological restoration of As contaminated soils are discussed. - Both white clover and ryegrass highly depend on the mycorrhizal associations for surviving heavy arsenic contamination

  3. Reaction and interaction of mycorrhizae and rhizosphere

    International Nuclear Information System (INIS)

    Kottke, I.

    1989-01-01

    Mycorrhizae of forest trees react and interact in a sensitive manner to environmental stress but have evolved adaption mechanism. Soil acidification causes no reduction of mycorrhizal frequency but shorter life span which is frequently compensated for by a higher production rate of mycorrhizae. Mycorrhizae of Norway spruce preferentially develop in soil pores. Nutrient availability probably relies more on the exchangeable ions at the surfaces of the pores than on the total ion exchange capacity. Additionally, organically bound compounds are mobilized by fungal hyphae and interaction on the rhizoplane. A lack of soil pores results in severe difficulties for Norway spruce to penetrate soil and to maintain mycorrhizal acticity. Water stress in the top soil causing a high percentage of dormant and dead mycorrhizae can be compensated for by a higher mycorrhizal production in deeper soil layers. At low nutrient availability in the mineral soil preferentially development of mycorrhizae is observed in the organic layer that may be regarded as an internal regulation mechanism, not as a toxic effect caused by Al in the mineral soil. Differentiated hyphal mantles protect mycorrhizae against water stress by impermeability and enhanced trehalose content and serve as storage and detoxification organs. There are indications of mycorrhizal types specially adapted to acidified soil conditions. (orig./vhe)

  4. Mycorrhization between Cistus ladanifer L. and Boletus edulis Bull is enhanced by the mycorrhiza helper bacteria Pseudomonas fluorescens Migula.

    Science.gov (United States)

    Mediavilla, Olaya; Olaizola, Jaime; Santos-del-Blanco, Luis; Oria-de-Rueda, Juan Andrés; Martín-Pinto, Pablo

    2016-02-01

    Boletus edulis Bull. is one of the most economically and gastronomically valuable fungi worldwide. Sporocarp production normally occurs when symbiotically associated with a number of tree species in stands over 40 years old, but it has also been reported in 3-year-old Cistus ladanifer L. shrubs. Efforts toward the domestication of B. edulis have thus focused on successfully generating C. ladanifer seedlings associated with B. edulis under controlled conditions. Microorganisms have an important role mediating mycorrhizal symbiosis, such as some bacteria species which enhance mycorrhiza formation (mycorrhiza helper bacteria). Thus, in this study, we explored the effect that mycorrhiza helper bacteria have on the efficiency and intensity of the ectomycorrhizal symbiosis between C. ladanifer and B. edulis. The aim of this work was to optimize an in vitro protocol for the mycorrhizal synthesis of B. edulis with C. ladanifer by testing the effects of fungal culture time and coinoculation with the helper bacteria Pseudomonas fluorescens Migula. The results confirmed successful mycorrhizal synthesis between C. ladanifer and B. edulis. Coinoculation of B. edulis with P. fluorescens doubled within-plant mycorrhization levels although it did not result in an increased number of seedlings colonized with B. edulis mycorrhizae. B. edulis mycelium culture time also increased mycorrhization levels but not the presence of mycorrhizae. These findings bring us closer to controlled B. edulis sporocarp production in plantations.

  5. Sulfate and glutathione enhanced arsenic accumulation by arsenic hyperaccumulator Pteris vittata L

    International Nuclear Information System (INIS)

    Wei Shuhe; Ma, Lena Q.; Saha, Uttam; Mathews, Shiny; Sundaram, Sabarinath; Rathinasabapathi, Bala; Zhou Qixing

    2010-01-01

    This experiment examined the effects of sulfate (S) and reduced glutathione (GSH) on arsenic uptake by arsenic hyperaccumulator Pteris vittata after exposing to arsenate (0, 15 or 30 mg As L -1 ) with sulfate (6.4, 12.8 or 25.6 mg S L -1 ) or GSH (0, 0.4 or 0.8 mM) for 2-wk. Total arsenic, S and GSH concentrations in plant biomass and arsenic speciation in the growth media and plant biomass were determined. While both S (18-85%) and GSH (77-89%) significantly increased arsenic uptake in P. vittata, GSH also increased arsenic translocation by 61-85% at 0.4 mM (p < 0.05). Sulfate and GSH did not impact plant biomass or arsenic speciation in the media and biomass. The S-induced arsenic accumulation by P. vittata was partially attributed to increased plant GSH (21-31%), an important non-enzymatic antioxidant countering oxidative stress. This experiment demonstrated that S and GSH can effectively enhance arsenic uptake and translocation by P. vittata. - Sulfate and glutathione increased arsenic uptake and translocation in Pteris vittata.

  6. Removal of arsenic from contaminated water using coagulation enhanced microfiltration

    International Nuclear Information System (INIS)

    Volchek, K.; Velicogna, D.; Dumouchel, A.; Wong, W.P.; Brown, C.E.

    2002-01-01

    Results of an innovative arsenic removal process were presented. The process is based on a combination of coagulation and microfiltration processes. Coagulation-Enhanced Microfiltration (CEMF) may eventually become a full-scale commercial technology. This study focused on the process with respect to groundwater treatment because of the importance of arsenic contamination in drinking water. Most experiments were bench-scale using tap water spiked with arsenic. Ferric chloride, which is commonly used in arsenic removal processes was also added. In addition, some tests were conducted on actual arsenic-contaminated water from the effluent treatment plant of a former mining site in Ontario. Results indicate a high arsenic removal efficiency in both spiked and actual water solutions. The microfiltration significantly reduced the level of arsenic in the treatment. This paper described the characteristics of membrane separation. It also presented information regarding chemically enhanced membrane filtration and coagulation-enhanced microfiltration. Bench-scale tests were conducted with both tubular membranes and with immersed capillary membranes. The effect of iron to arsenic ratios on the effectiveness of the system was also tested. It was recommended that future research should include a field study of the process on a pilot-scale to optimize process parameters and to accurately determine the cost of the process. 16 refs., 8 tabs., 9 figs

  7. Carbon-enhanced inductively coupled plasma mass spectrometric detection of arsenic and selenium and its application to arsenic speciation

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Sturup, Stefan

    1994-01-01

    Addition of carbon as methanol or ammonium carbonate to the aqueous analyte solutions in combination with increased plasma power input enhanced the inductively coupled plasma mass spectrometry (ICP-MS) signal intensities of arsenic and selenium. In the presence of the optimum 3% v/v methanol...... (noise) was not increased. Therefore, the observed increase in analyte sensitivity led to a similar increase in signal-to-noise ratio. The addition of carbon as ammonium carbonate enhanced the arsenic signal by a similar factor but caused severe contamination of the ICP-MS instrument by carbon. In the 3....../nebulization efficiency. It is proposed that an increased population of carbon ions or carbon-containing ions in the plasma facilitates a more complete ionization of analytes lower in ionization energy than carbon itself. The enhanced detection power for arsenic was applied to arsenic speciation by high...

  8. Effects of arbuscular mycorrhiza inoculation on growth and yield of tomato (Lycopersicum esculentum Mill. under salinity stress

    Directory of Open Access Journals (Sweden)

    D.R.R. Damaiyanti

    2015-10-01

    Full Text Available Objective of the research was to study the effect mycorrhiza on growth and yield of tomato. The experiment was conducted in screen house 14 m x 10.5 m, in Pasuruan on November 2013 until March 2014, The experiment was conducted as a factorial randomized complete design. The first factor was dose of mycorrhiza (without mycorrhiza, 5 g mycorrhiza, 10 g mycorrhiza, and 20 g mycorrhiza. The second factor was the salinity stress level (without NaCl, 2500 ppm NaCl, 5000 ppm NaCl, and 7500 ppm NaCl. The results showed that salinity stress at the level 7500 ppm decreased the amount of fruit by 30.84% and fresh weight per hectare decreased by 51.72%. Mycorrhizal application was not able to increase the growth and yield in saline stress conditions; it was shown by the level of infection and the number of spores on the roots of tomato plants lower the salinity level 5000 ppm and 7500 ppm. But separately, application of 20 g mycorrhiza enhanced plant growth, such as plant height, leaf area, leaf number and proline. Application of 20 g mycorrhiza increased the yield by 35.99%.

  9. Chronic subhepatotoxic exposure to arsenic enhances hepatic injury caused by high fat diet in mice

    International Nuclear Information System (INIS)

    Tan, Min; Schmidt, Robin H.; Beier, Juliane I.; Watson, Walter H.; Zhong, Hai; States, J. Christopher; Arteel, Gavin E.

    2011-01-01

    Arsenic is a ubiquitous contaminant in drinking water. Whereas arsenic can be directly hepatotoxic, the concentrations/doses required are generally higher than present in the US water supply. However, physiological/biochemical changes that are alone pathologically inert can enhance the hepatotoxic response to a subsequent stimulus. Such a ‘2-hit’ paradigm is best exemplified in chronic fatty liver diseases. Here, the hypothesis that low arsenic exposure sensitizes liver to hepatotoxicity in a mouse model of non-alcoholic fatty liver disease was tested. Accordingly, male C57Bl/6J mice were exposed to low fat diet (LFD; 13% calories as fat) or high fat diet (HFD; 42% calories as fat) and tap water or arsenic (4.9 ppm as sodium arsenite) for ten weeks. Biochemical and histologic indices of liver damage were determined. High fat diet (± arsenic) significantly increased body weight gain in mice compared with low-fat controls. HFD significantly increased liver to body weight ratios; this variable was unaffected by arsenic exposure. HFD caused steatohepatitis, as indicated by histological assessment and by increases in plasma ALT and AST. Although arsenic exposure had no effect on indices of liver damage in LFD-fed animals, it significantly increased the liver damage caused by HFD. This effect of arsenic correlated with enhanced inflammation and fibrin extracellular matrix (ECM) deposition. These data indicate that subhepatotoxic arsenic exposure enhances the toxicity of HFD. These results also suggest that arsenic exposure might be a risk factor for the development of fatty liver disease in human populations. -- Highlights: ► Characterizes a mouse model of arsenic enhanced NAFLD. ► Arsenic synergistically enhances experimental fatty liver disease at concentrations that cause no overt hepatotoxicity alone. ► This effect is associated with increased inflammation.

  10. Characterization of Tuber borchii and Arbutus unedo mycorrhizas.

    Science.gov (United States)

    Lancellotti, Enrico; Iotti, Mirco; Zambonelli, Alessandra; Franceschini, Antonio

    2014-08-01

    For the first time, arbutoid mycorrhizas established between Tuber borchii and Arbutus unedo were described. Analyzed mycorrhizas were from one T. borchii natural truffle ground, dominated by Pinus pinea, as well as synthesized in greenhouse conditions. A. unedo mycorrhizas presented some typical characteristics of ectomycorrhizas of T. borchii. However, as in arbutoid mycorrhizas, ramification was cruciform and intracellular colonization in epidermal cells was present. The ability of T. borchii to form ectomycorrhizas with A. unedo opens up the possibility to also use this fruit plant for truffle cultivation. This represents an important economic opportunity in Mediterranean areas by combining both the cultivation of precious truffles and the production of edible fruits which are used fresh or in food delicacies.

  11. Enhanced phytoremediation of arsenic contaminated land.

    Science.gov (United States)

    Jankong, P; Visoottiviseth, P; Khokiattiwong, S

    2007-08-01

    In an attempt to clean up arsenic (As) contaminated soil, the effects of phosphorus (P) fertilizer and rhizosphere microbes on arsenic accumulation by the silverback fern, Pityrogramma calomelanos, were investigated in both greenhouse and field experiments. Field experiments were conducted in Ron Phibun District, an As-contaminated area in Thailand. Soil (136-269 microg As g(-1)) was collected there and used in the greenhouse experiment. Rhizosphere microbes (bacteria and fungi) were isolated from roots of P. calomelanos growing in Ron Phibun District. The results showed that P-fertilizer significantly increased plant biomass and As accumulation of the experimental P. calomelanos. Rhizobacteria increased significantly the biomass and As content of the test plants. Thus, P-fertilizer and rhizosphere bacteria enhanced As-phytoextraction. In contrast, rhizofungi reduced significantly As concentration in plants but increased plant biomass. Therefore, rhizosphere fungi exerted their effects on phytostabilization.

  12. Use of arbuscular mycorrhiza fungi for improved crop production in ...

    African Journals Online (AJOL)

    Arbuscular mycorrhiza fungi (AMF), endophytic fungi reputed for their ability to enhance P uptake can be used to alleviate P deficiencies and improve crop productivity. Although the technology has been used in developed countries, it has not been applied in crop production systems in Africa to any significant level. This is ...

  13. The influence of vesicular-arbuscular mycorrhizas on production ...

    African Journals Online (AJOL)

    arbuscular mycorrhizas produced slight increases in dry mater production in unsterilized field plots at Cedara, Natal. Phosphorus levels in plant tops showed no increases due to mycorrhizas but crude protein content of all mycorrhizal plants were ...

  14. Radiocaesium in fruitbodies and mycorrhizae in ectomycorrhizal fungi

    International Nuclear Information System (INIS)

    Nikolova, Ivanka; Johanson, K.J.; Dahlberg, Anders

    1997-01-01

    Fruitbodies of Suillus variegatus and Lactarius rufus and, at a maximum distance of 50 cm, the corresponding mycorrhizae, were collected on a rocky area in a coniferous forest. The tuberculate mycorrhizae collected close to S. variegatus fruitbodies were identified by the RFLP pattern to be S. variegatus mycorrhizae. In contrast the smooth brown mycorrhizae collected close to fruitbodies of L. rufus were found to be of various species - L. rufus, but also Russula sp. The 137 Cs activity concentrations in fruitbodies and the fungal part of the tuburculate mycorrhizae of S. variegatus were about the same. A local enrichment of 137 Cs within fruitbodies was studied by collecting fruitbodies growing in clusters. Between 13 and 64% of the mean ground 137 Cs deposition of the cluster area (400 or 625 cm 2 ) was found in the fruitbodies. This indicates that there might be an important fungal redistribution of 137 Cs in the forest floor during the production of fruitbodies. The distribution of 137 Cs within the fruitbodies was heterogenous. For example in Cortinarious armillatus, the 137 Cs level in the cap was 2.7 times higher compared to in the stripe. (Author)

  15. Radiocaesium in fruitbodies and mycorrhizae in ectomycorrhizal fungi

    Energy Technology Data Exchange (ETDEWEB)

    Nikolova, Ivanka [N. Pouskharov Inst. of Soil Sciences and Agroecology, Sofia (Bulgaria); Johanson, K.J. [Swedish Univ. of Agricultural Sciences, Radioecology Dept., Uppsala (Sweden); Dahlberg, Anders [Swedish Univ. of Agricultural Sciences, Forest Mycology and Pathology Dept., Uppsala (Sweden)

    1997-12-31

    Fruitbodies of Suillus variegatus and Lactarius rufus and, at a maximum distance of 50 cm, the corresponding mycorrhizae, were collected on a rocky area in a coniferous forest. The tuberculate mycorrhizae collected close to S. variegatus fruitbodies were identified by the RFLP pattern to be S. variegatus mycorrhizae. In contrast the smooth brown mycorrhizae collected close to fruitbodies of L. rufus were found to be of various species - L. rufus, but also Russula sp. The {sup 137}Cs activity concentrations in fruitbodies and the fungal part of the tuburculate mycorrhizae of S. variegatus were about the same. A local enrichment of {sup 137}Cs within fruitbodies was studied by collecting fruitbodies growing in clusters. Between 13 and 64% of the mean ground {sup 137}Cs deposition of the cluster area (400 or 625 cm{sup 2}) was found in the fruitbodies. This indicates that there might be an important fungal redistribution of {sup 137}Cs in the forest floor during the production of fruitbodies. The distribution of {sup 137}Cs within the fruitbodies was heterogenous. For example in Cortinarious armillatus, the {sup 137}Cs level in the cap was 2.7 times higher compared to in the stripe. (Author).

  16. Mycorrhiza of Dryopteris carthusiana in southern Poland

    Directory of Open Access Journals (Sweden)

    Juliusz Unrug

    2014-08-01

    Full Text Available The research on mycorrhiza of Dryopteris carthusiana from natural sites and those contaminated by heavy metals (Niepołomice Forest, both on lowlands and mountainous areas in Poland, was carried out. Mycorrhizal colonization of Arum-type was higher in ferns growing on tree stumps than in specimens developing directly on the soil. Additionally, an increase in mycorrhiza intensity and arbuscular richness with the rising ground humidity was observed. In comparison to natural sites, mycorrhizas from the areas contaminated by heavy metals were much less developed and the roots were often infected by parasites. Two morphotypes of mycorrhizal fungi have been described The most common was a fine endophyte (Glomales.

  17. The influence of arbuscular mycorrhizae on root precision nutrient foraging of two pioneer plant species during early reclamation

    Science.gov (United States)

    Boldt-Burisch, Katja; Naeth, M. Anne

    2017-04-01

    On many post mining sites in the Lusatian Mining District (East Germany) soil heterogeneity consists of sandy soil with embedded clay-silt fragments. Those clays silt fragments might act as nutrient hotspots. Arbuscular mycorrhizal fungi in an infertile ecosystem could enhance a plant's ability to selectively forage for those nutrients and thus to improve plants nutrient supply. In our study we investigated whether silt-clay fragments within a sandy soil matrix induced preferential root growth of Lotus corniculatus and Calamagrostis epigeios, whether arbuscular mycorrhizae influenced root foraging patterns, and to what extent selective rooting in clay silt fragments influenced plant growth were addressed in this research. Soil types were sterile and non-sterile sandy soil and clay-silt fragments. Treatments were with and without arbuscular mycorrhizae, with and without soil solution, and soil solution and mycorrhizal inoculum combined. Root biomass, root density and intraradical fungal alkaline phosphatase activity and frequency were determined in fragments relative to sandy soil. Furthermore, temporal relationship of number of roots in fragments and plant height was assessed. Lotus corniculatus showed strong selective rooting into fragments especially with those plants treated with commercial cultivated arbuscular mycorrhizae; Calamagrostis epigeios did not. Without arbuscular mycorrhizae, L. corniculatus growth was significantly reduced and selective rooting did not occur. Selective rooting induced significant growth spurts of L. corniculatus. Roots in fragments had higher fungal alkaline phosphatase activity suggesting that mycorrhizal efficiency and related plants phosphorus supply is enhanced in roots in fragments. The application of cultivated arbuscular mycorrhizal fungi significantly and quickly influenced root foraging patterns, especially those of L. corniculatus, suggesting mycorrhizae may also enhance the ability of other plants to selectively forage

  18. Ethanol enhances arsenic-induced cyclooxygenase-2 expression via both NFAT and NF-κB signalings in colorectal cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lei; Hitron, John Andrew [Center for Research on Environmental Disease, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Wise, James T.F. [Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Son, Young-Ok; Roy, Ram Vinod [Center for Research on Environmental Disease, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Kim, Donghern; Dai, Jin [Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Pratheeshkumar, Poyil [Center for Research on Environmental Disease, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Zhang, Zhuo [Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Xu, Mei; Luo, Jia [Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Shi, Xianglin, E-mail: xshi5@uky.edu [Center for Research on Environmental Disease, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States)

    2015-10-15

    Arsenic is a known carcinogen to humans, and chronic exposure to environmental arsenic is a worldwide health concern. As a dietary factor, ethanol carries a well-established risk for malignancies, but the effects of co-exposure to arsenic and ethanol on tumor development are not well understood. In the present study, we hypothesized that ethanol would enhance the function of an environmental carcinogen such as arsenic through increase in COX-2 expression. Our in vitro results show that ethanol enhanced arsenic-induced COX-2 expression. We also show that the increased COX-2 expression associates with intracellular ROS generation, up-regulated AKT signaling, with activation of both NFAT and NF-κB pathways. We demonstrate that antioxidant enzymes have an inhibitory effect on arsenic/ethanol-induced COX-2 expression, indicating that the responsive signaling pathways from co-exposure to arsenic and ethanol relate to ROS generation. In vivo results also show that co-exposure to arsenic and ethanol increased COX-2 expression in mice. We conclude that ethanol enhances arsenic-induced COX-2 expression in colorectal cancer cells via both the NFAT and NF-κB pathways. These results imply that, as a common dietary factor, ethanol ingestion may be a compounding risk factor for arsenic-induced carcinogenesis/cancer development. - Highlights: • Arsenic is able to induce Cox-2 expression in colorectal cancer cells. • Ethanol, a diet nutritional factor, could enhance arsenic-induced Cox-2. • The up-regulation of Cox-2 via both NFAT and NF-κB activities.

  19. Ethanol enhances arsenic-induced cyclooxygenase-2 expression via both NFAT and NF-κB signalings in colorectal cancer cells

    International Nuclear Information System (INIS)

    Wang, Lei; Hitron, John Andrew; Wise, James T.F.; Son, Young-Ok; Roy, Ram Vinod; Kim, Donghern; Dai, Jin; Pratheeshkumar, Poyil; Zhang, Zhuo; Xu, Mei; Luo, Jia; Shi, Xianglin

    2015-01-01

    Arsenic is a known carcinogen to humans, and chronic exposure to environmental arsenic is a worldwide health concern. As a dietary factor, ethanol carries a well-established risk for malignancies, but the effects of co-exposure to arsenic and ethanol on tumor development are not well understood. In the present study, we hypothesized that ethanol would enhance the function of an environmental carcinogen such as arsenic through increase in COX-2 expression. Our in vitro results show that ethanol enhanced arsenic-induced COX-2 expression. We also show that the increased COX-2 expression associates with intracellular ROS generation, up-regulated AKT signaling, with activation of both NFAT and NF-κB pathways. We demonstrate that antioxidant enzymes have an inhibitory effect on arsenic/ethanol-induced COX-2 expression, indicating that the responsive signaling pathways from co-exposure to arsenic and ethanol relate to ROS generation. In vivo results also show that co-exposure to arsenic and ethanol increased COX-2 expression in mice. We conclude that ethanol enhances arsenic-induced COX-2 expression in colorectal cancer cells via both the NFAT and NF-κB pathways. These results imply that, as a common dietary factor, ethanol ingestion may be a compounding risk factor for arsenic-induced carcinogenesis/cancer development. - Highlights: • Arsenic is able to induce Cox-2 expression in colorectal cancer cells. • Ethanol, a diet nutritional factor, could enhance arsenic-induced Cox-2. • The up-regulation of Cox-2 via both NFAT and NF-κB activities.

  20. Effect of mycorrhiza symbiosis on the Nacl salinity in Sorghum bicolor

    African Journals Online (AJOL)

    Jane

    2011-08-01

    Aug 1, 2011 ... Khajehzadeh, 1996). Mycorrhiza is a mutual symbiosis between thallus of some fungi and the root of organic plants. In nature, mycorrhiza is important in satisfying the needs of the plants for water and nutrition. Among the microorganisms living in the soil, arbuscular mycorrhiza fungi are especially important ...

  1. Mycorrhiza and crop production

    Energy Technology Data Exchange (ETDEWEB)

    Hayman, D S

    1980-10-09

    This article describes recent research with vesicular-arbuscular mycorrhiza, a symbiotic fungus-root association. The suggestion that the symbiotic association may be harnessed to achieve more economical use of phosphate fertilizers is discussed and the results from various test crops are given.

  2. Effects of Arbuscular Mycorrhiza on Osmotic Adjustment and Photosynthetic Physiology of Maize Seedlings in Black Soils Region of Northeast China

    Directory of Open Access Journals (Sweden)

    Hongwen Xu

    Full Text Available ABSTRACT To investigate the effect of arbuscular mycorrhiza fungi on maize growth, osmoregulation substances and photosynthetic physiology, a popular maize variety ZD 958 was measured under potted condition. Arbuscular mycorrhiza (AM symbiosis promoted plant growth, and enhanced plant height, leaf length, mean leaf width and dry weight. Higher soluble sugar and protein, but lower proline concentrations were detected in AM seedlings than corresponding non-AM seedlings. Quantum yield of PSII photochemistry and potential photochemical efficiency increased by arbuscular mycorrhiza fungi, meanwhile, AM plants had lower primary fluorescence but higher maximal fluorescence and variable fluorescence than non-AM plants. AM enhanced apparent quantum efficiency, maximum net photosynthetic rate, dark respiration rate and light saturation point, but reduced light compensation point. The conclusion was that, after the seedling inoculated with Glomus. tortuosum, AM symbioses could protect cell from being hurt through regulating substances related to osmotic adjustment, besides, the efficiency of light utilization, the capacity of using low light and the capacity of fitting and using high light were all increased by AM symbiosis.

  3. The effect of potassium and mycorrhiza on growth of vanilla (Vanilla planifolia Andrew

    Directory of Open Access Journals (Sweden)

    I GEDE TIRTA

    2006-04-01

    Full Text Available The few and shallow roots caused slow growth of vanilla seedling. Mycorrhiza may increased the absorption of water and nutrients, while potassium may increased the rate of growth and strength of seedlings. This study was conducted at Sambangan Village, Buleleng, Bali in 2003 (April-Agustus 2003. The experiment was done in polybag and was arranged in Randomized Block Design with three replications. The treatments were consisted of two factors. The first factor was the rates of KCl fertilizer ( 0, 100 and 200 kg ha-1 or 0, 0,10 and 0,20 9 plant-1 and the second factor was the rates of mycorrhiza (0, 20 and 30 g plant-1. The aim of the research to study interactions between potassium and mycorrhiza and The optimum dosage the mycorrhiza on growth of vanilla (Vanilla planifolia Andrew. The resultes showed that there were interactions between potassium and mycorrhiza on fresh weight of the new shoot, root length and fresh root weight. The optimum dosage of the mycorrhiza was 20 g plant-1 with new shoot fresh weight was 25.63 g plant-1. The longest root (24.67 cm plant-1 was observed at the treatment without potasium with 20 g plant-1 mycorrhiza and this was 23% longer than control (19.93 cm plant-1. The highest fresh root weight (2.48 g plant-1 was observed at the dosage of 200 kg KCl ha-1 and 20 g mycorrhiza plant-1 and that was 55% heavier than control (1.60 g plant-1. The leaf number of the plant with 20 g plant-1 mycorrhiza was 6.22 and that was 18% more than control with leaf number 5.25. The total fresh weight of the seedling with 20 g plant-1 mycorrhiza was 86.74 g plant-1or 15% higher compared with control (75.18 g plant-1. The dosage of 100 kg KCl ha-1 increased the K content of the plant (2.45%K or 35% higher than control (1.81%K.

  4. Both Phosphorus Fertilizers and Indigenous Bacteria Enhance Arsenic Release into Groundwater in Arsenic-Contaminated Aquifers.

    Science.gov (United States)

    Lin, Tzu-Yu; Wei, Chia-Cheng; Huang, Chi-Wei; Chang, Chun-Han; Hsu, Fu-Lan; Liao, Vivian Hsiu-Chuan

    2016-03-23

    Arsenic (As) is a human carcinogen, and arsenic contamination in groundwater is a worldwide public health concern. Arsenic-affected areas are found in many places but are reported mostly in agricultural farmlands, yet the interaction of fertilizers, microorganisms, and arsenic mobilization in arsenic-contaminated aquifers remains uncharacterized. This study investigates the effects of fertilizers and bacteria on the mobilization of arsenic in two arsenic-contaminated aquifers. We performed microcosm experiments using arsenic-contaminated sediments and amended with inorganic nitrogenous or phosphorus fertilizers for 1 and 4 months under aerobic and anaerobic conditions. The results show that microcosms amended with 100 mg/L phosphorus fertilizers (dipotassium phosphate), but not nitrogenous fertilizers (ammonium sulfate), significantly increase aqueous As(III) release in arsenic-contaminated sediments under anaerobic condition. We also show that concentrations of iron, manganese, potassium, sodium, calcium, and magnesium are increased in the aqueous phase and that the addition of dipotassium phosphate causes a further increase in aqueous iron, potassium, and sodium, suggesting that multiple metal elements may take part in the arsenic release process. Furthermore, microbial analysis indicates that the dominant microbial phylum is shifted from α-proteobacteria to β- and γ-proteobacteria when the As(III) is increased and phosphate is added in the aquifer. Our results provide evidence that both phosphorus fertilizers and microorganisms can mediate the release of arsenic to groundwater in arsenic-contaminated sediments under anaerobic condition. Our study suggests that agricultural activity such as the use of fertilizers and monitoring phosphate concentration in groundwater should be taken into consideration for the management of arsenic in groundwater.

  5. The fficiency of Mycorrhiza biofertilizer treatment to the growth and yield of soybean

    Science.gov (United States)

    Samanhudi; Pujiasmanto, B.; Sudadi; Putra, I. H.; Mumtazah, H. M.

    2018-03-01

    Soybean is one of the major commodities in Indonesia. Due to its high demand, its requires an effort to increase the production. Soybeans are generally cultivated in dry land, for that its need a special management to increase the yield. The association between Mycorrhiza and roots help the plant to get water and nutrients. In this regard Mycorrhiza expected to increase soybean yield and efficiency. This research aim is to study the dose of Mycorrhiza on the growth and yield of soybean efficiently. The experiment was conducted in Selogiri District, Wonogiri, while the analysis of Mycorrhiza and soil was inFaculty of Agriculture, Universitas Sebelas Maret Surakarta from February to April 2016. Randomized Complete Block Design (RCBD) with two factors was emplyed for this experiment. The treatments are compost dose (derived from Waste Management Faculty of Agriculture UNS) and Mycorrhizal dose (obtained from BPPT Serpong). The result showed that the Mycorrhiza treatmentwas able to improved the growth and yield of soybean. The most efficient dose of is Mycorrhiza treatment at 0.64 ton ha-1.

  6. Arsenic transformation predisposes human skin keratinocytes to UV-induced DNA damage yet enhances their survival apparently by diminishing oxidant response

    International Nuclear Information System (INIS)

    Sun Yang; Kojima, Chikara; Chignell, Colin; Mason, Ronald; Waalkes, Michael P.

    2011-01-01

    Inorganic arsenic and UV, both human skin carcinogens, may act together as skin co-carcinogens. We find human skin keratinocytes (HaCaT cells) are malignantly transformed by low-level arsenite (100 nM, 30 weeks; termed As-TM cells) and with transformation concurrently undergo full adaptation to arsenic toxicity involving reduced apoptosis and oxidative stress response to high arsenite concentrations. Oxidative DNA damage (ODD) is a possible mechanism in arsenic carcinogenesis and a hallmark of UV-induced skin cancer. In the current work, inorganic arsenite exposure (100 nM) did not induce ODD during the 30 weeks required for malignant transformation. Although acute UV-treatment (UVA, 25 J/cm 2 ) increased ODD in passage-matched control cells, once transformed by arsenic to As-TM cells, acute UV actually further increased ODD (> 50%). Despite enhanced ODD, As-TM cells were resistant to UV-induced apoptosis. The response of apoptotic factors and oxidative stress genes was strongly mitigated in As-TM cells after UV exposure including increased Bcl2/Bax ratio and reduced Caspase-3, Nrf2, and Keap1 expression. Several Nrf2-related genes (HO-1, GCLs, SOD) showed diminished responses in As-TM cells after UV exposure consistent with reduced oxidant stress response. UV-exposed As-TM cells showed increased expression of cyclin D1 (proliferation gene) and decreased p16 (tumor suppressor). UV exposure enhanced the malignant phenotype of As-TM cells. Thus, the co-carcinogenicity between UV and arsenic in skin cancer might involve adaptation to chronic arsenic exposure generally mitigating the oxidative stress response, allowing apoptotic by-pass after UV and enhanced cell survival even in the face of increased UV-induced oxidative stress and increased ODD. - Highlights: → Arsenic transformation adapted to UV-induced apoptosis. → Arsenic transformation diminished oxidant response. → Arsenic transformation enhanced UV-induced DNA damage.

  7. Arbuscular mycorrhiza in soil quality assessment

    DEFF Research Database (Denmark)

    Kling, M.; Jakobsen, I.

    1998-01-01

    aggregates and to the protection of plants against drought and root pathogens. Assessment of soil quality, defined as the capacity of a soil to function within ecosystem boundaries to sustain biological productivity, maintain environmental quality, and promote plant health, should therefore include both......Arbuscular mycorrhizal (AM) fungi constitute a living bridge for the transport of nutrients from soil to plant roots, and are considered as the group of soil microorganisms that is of most direct importance to nutrient uptake by herbaceous plants. AM fungi also contribute to the formation of soil...... quantitative and qualitative measurements of this important biological resource. Various methods for the assessment of the potential for mycorrhiza formation and function are presented. Examples are given of the application of these methods to assess the impact of pesticides on the mycorrhiza....

  8. Enhancements of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) metabolism and carcinogenic risk via NNK/arsenic interaction

    International Nuclear Information System (INIS)

    Lee, H.-L.; Chang, Louis W.; Wu, J.-P.; Ueng, Y.-F.; Tsai, M.-H.; Hsieh, Dennis Paul Hsientang; Lin Pinpin

    2008-01-01

    Epidemiological studies indicated an enhancement of cigarette smoke-induced carcinogenicity, including hepatocellular carcinoma, by arsenic. We believe that arsenic will enhance the expression of hepatic CYP2A enzyme and NNK metabolism (a cigarette smoke component), thus its metabolites, and carcinogenic DNA adducts. Male ICR mice were exposed to NNK (0.5 mg/mouse) and sodium arsenite (0, 10, or 20 mg/kg) daily via gavaging for 10 days and their urine was collected at day 10 for NNK metabolite analysis. Liver samples were also obtained for CYP2A enzyme and DNA adducts evaluations. Both the cyp2a4/5 mRNA levels and the CYP2A enzyme activity were significantly elevated in arsenic-treated mice liver. Furthermore, urinary NNK metabolites in NNK/arsenic co-treated mice also increased compared to those treated with NNK alone. Concomitantly, DNA adducts (N 7 -methylguanine and O 6 -methylguanine) were significantly elevated in the livers of mice co-treated with NNK and arsenic. Our findings provide clear evidence that arsenic increased NNK metabolism by up-regulation of CYP2A expression and activity leading to an increased NNK metabolism and DNA adducts (N 7 -methylguanine and O 6 -methylguanine). These findings suggest that in the presence of arsenic, NNK could induce greater DNA adducts formation in hepatic tissues resulting in higher carcinogenic potential

  9. Diversity and evolution of ABC proteins in mycorrhiza-forming fungi.

    Science.gov (United States)

    Kovalchuk, Andriy; Kohler, Annegret; Martin, Francis; Asiegbu, Fred O

    2015-12-28

    Transporter proteins are predicted to have an important role in the mycorrhizal symbiosis, due to the fact that this type of an interaction between plants and fungi requires a continuous nutrient and signalling exchange. ABC transporters are one of the large groups of transporter proteins found both in plants and in fungi. The crucial role of plant ABC transporters in the formation of the mycorrhizal symbiosis has been demonstrated recently. Some of the fungal ABC transporter-encoding genes are also induced during the mycorrhiza formation. However, no experimental evidences of the direct involvement of fungal ABC transporters in this process are available so far. To facilitate the identification of fungal ABC proteins with a potential role in the establishment of the mycorrhizal symbiosis, we have performed an inventory of the ABC protein-encoding genes in the genomes of 25 species of mycorrhiza-forming fungi. We have identified, manually annotated and curated more than 1300 gene models of putative ABC protein-encoding genes. Out of those, more than 1000 models are predicted to encode functional proteins, whereas about 300 models represent gene fragments or putative pseudogenes. We have also performed the phylogenetic analysis of the identified sequences. The sets of ABC proteins in the mycorrhiza-forming species were compared to the related saprotrophic or plant-pathogenic fungal species. Our results demonstrate the high diversity of ABC genes in the genomes of mycorrhiza-forming fungi. Via comparison of transcriptomics data from different species, we have identified candidate groups of ABC transporters that might have a role in the process of the mycorrhiza formation. Results of our inventory will facilitate the identification of fungal transporters with a role in the mycorrhiza formation. We also provide the first data on ABC protein-coding genes for the phylum Glomeromycota and for orders Pezizales, Atheliales, Cantharellales and Sebacinales, contributing to

  10. Novel chitosan/PVA/zerovalent iron biopolymeric nanofibers with enhanced arsenic removal applications.

    Science.gov (United States)

    Chauhan, Divya; Dwivedi, Jaya; Sankararamakrishnan, Nalini

    2014-01-01

    Enhanced removal application of both forms of inorganic arsenic from arsenic-contaminated aquifers at near-neutral pH was studied using a novel electrospun chitosan/PVA/zerovalent iron (CPZ) nanofibrous mat. CPZ was carefully examined using scanning electron microscopy (SEM) equipped with energy-dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), atomic fluorescence spectroscopy (AFM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermal gravimetric analysis (TGA). Application of the adsorbent towards the removal of total inorganic arsenic in batch mode has also been studied. A suitable mechanism for the adsorption has also been discussed. CPZ nanofibers mat was found capable to remove 200.0±10.0 mg g(-1) of As(V) and 142.9±7.2 mg g(-1) of As(III) from aqueous solution of pH 7.0 at ambient condition. Addition of ethylenediaminetetraacetic acid (EDTA) enabled the stability of iron in zerovalent state (ZVI). Enhanced capacity of the fibrous mat could be attributed to the high surface area of the fibers, presence of ZVI, and presence of functional groups such as amino, carboxyl, and hydroxyl groups of the chitosan and EDTA. Both Langmuir and Freundlich adsorption isotherms were applicable to describe the removal process. The possible mechanism of adsorption has been explained in terms of electrostatic attraction between the protonated amino groups of chitosan/arsenate ions and oxidation of arsenite to arsenate by Fentons generated from ZVI and subsequent complexation of the arsenate with the oxidized iron. These CPZ nanofibrous mats has been prepared with environmentally benign naturally occurring biodegradable biopolymer chitosan, which offers unique advantage in the removal of arsenic from contaminated groundwater.

  11. Hijacking membrane transporters for arsenic phytoextraction

    Science.gov (United States)

    LeBlanc, Melissa S.; McKinney, Elizabeth C.; Meagher, Richard B.; Smith, Aaron P.

    2012-01-01

    Arsenic is a toxic metalloid and recognized carcinogen. Arsenate and arsenite are the most common arsenic species available for uptake by plants. As an inorganic phosphate (Pi) analog, arsenate is acquired by plant roots through endogenous Pi transport systems. Inside the cell, arsenate is reduced to the thiol-reactive form arsenite. Glutathione (GSH)-conjugates of arsenite may be extruded from the cell or sequestered in vacuoles by members of the ATP-binding cassette (ABC) family of transporters. In the present study we sought to enhance both plant arsenic uptake through Pi transporter overexpression, and plant arsenic tolerance through ABC transporter overexpression. We demonstrate that Arabidopsis thaliana plants overexpressing the high-affinity Pi transporter family members, AtPht1;1 or AtPht1;7, are hypersensitive to arsenate due to increased arsenate uptake. These plants do not exhibit increased sensitivity to arsenite. Co-overexpression of the yeast ABC transporter YCF1 in combination with AtPht1;1 or AtPht1;7 suppresses the arsenate-sensitive phenotype while further enhancing arsenic uptake. Taken together, our results support an arsenic transport mechanism in which arsenate uptake is increased through Pi transporter overexpression, and arsenic tolerance is enhanced through YCF1-mediated vacuolar sequestration. This work substantiates the viability of coupling enhanced uptake and vacuolar sequestration as a means for developing a prototypical engineered arsenic hyperaccumulator. PMID:23108027

  12. Subchronic Arsenic Exposure Induces Anxiety-Like Behaviors in Normal Mice and Enhances Depression-Like Behaviors in the Chemically Induced Mouse Model of Depression

    Directory of Open Access Journals (Sweden)

    Chia-Yu Chang

    2015-01-01

    Full Text Available Accumulating evidence implicates that subchronic arsenic exposure causes cerebral neurodegeneration leading to behavioral disturbances relevant to psychiatric disorders. However, there is still little information regarding the influence of subchronic exposure to arsenic-contaminated drinking water on mood disorders and its underlying mechanisms in the cerebral prefrontal cortex. The aim of this study is to assess the effects of subchronic arsenic exposure (10 mg/LAs2O3 in drinking water on the anxiety- and depression-like behaviors in normal mice and in the chemically induced mouse model of depression by reserpine pretreatment. Our findings demonstrated that 4 weeks of arsenic exposure enhance anxiety-like behaviors on elevated plus maze (EPM and open field test (OFT in normal mice, and 8 weeks of arsenic exposure augment depression-like behaviors on tail suspension test (TST and forced swimming test (FST in the reserpine pretreated mice. In summary, in this present study, we demonstrated that subchronic arsenic exposure induces only the anxiety-like behaviors in normal mice and enhances the depression-like behaviors in the reserpine induced mouse model of depression, in which the cerebral prefrontal cortex BDNF-TrkB signaling pathway is involved. We also found that eight weeks of subchronic arsenic exposure are needed to enhance the depression-like behaviors in the mouse model of depression. These findings imply that arsenic could be an enhancer of depressive symptoms for those patients who already had the attribute of depression.

  13. Arbuscular mycorrhiza reduces phytoextraction of uranium, thorium and other elements from phosphate rock

    International Nuclear Information System (INIS)

    Roos, Per; Jakobsen, Iver

    2008-01-01

    Uptake of metals from uranium-rich phosphate rock was studied in Medicago truncatula plants grown in symbiosis with the arbuscular mycorrhizal fungus Glomus intraradices or in the absence of mycorrhizas. Shoot concentrations of uranium and thorium were lower in mycorrhizal than in non-mycorrhizal plants and root-to-shoot ratio of most metals was increased by mycorrhizas. This protective role of mycorrhizas was observed even at very high supplies of phosphate rock. In contrast, phosphorus uptake was similar at all levels of phosphate rock, suggesting that the P was unavailable to the plant-fungus uptake systems. The results support the role of arbuscular mycorrhiza as being an important component in phytostabilization of uranium. This is the first study to report on mycorrhizal effect and the uptake and root-to-shoot transfer of thorium from phosphate rock

  14. Arbuscular mycorrhiza reduces phytoextraction of uranium, thorium and other elements from phosphate rock

    Energy Technology Data Exchange (ETDEWEB)

    Roos, Per [Radiation Research Department, Riso National Laboratory, Technical University of Denmark, DK-4000 Roskilde (Denmark); Jakobsen, Iver [Biosystems Department, Riso National Laboratory, Technical University of Denmark, DK-4000 Roskilde (Denmark)], E-mail: iver.jakobsen@risoe.dk

    2008-05-15

    Uptake of metals from uranium-rich phosphate rock was studied in Medicago truncatula plants grown in symbiosis with the arbuscular mycorrhizal fungus Glomus intraradices or in the absence of mycorrhizas. Shoot concentrations of uranium and thorium were lower in mycorrhizal than in non-mycorrhizal plants and root-to-shoot ratio of most metals was increased by mycorrhizas. This protective role of mycorrhizas was observed even at very high supplies of phosphate rock. In contrast, phosphorus uptake was similar at all levels of phosphate rock, suggesting that the P was unavailable to the plant-fungus uptake systems. The results support the role of arbuscular mycorrhiza as being an important component in phytostabilization of uranium. This is the first study to report on mycorrhizal effect and the uptake and root-to-shoot transfer of thorium from phosphate rock.

  15. Effect of applying an arsenic-resistant and plant growth-promoting rhizobacterium to enhance soil arsenic phytoremediation by Populus deltoides LH05-17.

    Science.gov (United States)

    Wang, Q; Xiong, D; Zhao, P; Yu, X; Tu, B; Wang, G

    2011-11-01

    Bioremediation of highly arsenic (As)-contaminated soil is difficult because As is very toxic for plants and micro-organisms. The aim of this study was to investigate soil arsenic removal effects using poplar in combination with the inoculation of a plant growth-promoting rhizobacterium (PGPR). A rhizobacterium D14 was isolated and identified within Agrobacterium radiobacter. This strain was highly resistant to arsenic and produced indole acetic acid and siderophore. Greenhouse pot bioremediation experiments were performed for 5 months using poplar (Populus deltoides LH05-17) grown on As-amended soils, inoculated with strain D14. The results showed that P. deltoides was an efficient arsenic accumulator; however, high As concentrations (150 and 300 mg kg(-1)) inhibited its growth. With the bacterial inoculation, in the 300 mg kg(-1) As-amended soils, 54% As in the soil was removed, which was higher than the uninoculated treatments (43%), and As concentrations in roots, stems and leaves were significantly increased by 229, 113 and 291%, respectively. In addition, the As translocation ratio [(stems + leaves)/roots = 0·8] was significantly higher than the uninoculated treatments (0·5). About 45% As was translocated from roots to the above-ground tissues. The plant height and dry weight of roots, stems and leaves were all enhanced; the contents of chlorophyll and soluble sugar, and the activities of superoxide dismutase and catalase were all increased; and the content of a toxic compound malondialdehyde was decreased. The results indicated that the inoculation of strain D14 could contribute to the increase in the As tolerance of P. deltoides, promotion of the growth, increase in the uptake efficiency and enhancement of As translocation. The use of P. deltoides in combination with the inoculation of strain D14 provides a potential application for efficient soil arsenic bioremediation. © 2011 The Authors. Journal of Applied Microbiology ©2011 The Society for Applied

  16. Effect of Mycorrhiza Symbiosis on Yield, Yield Components and Water Use Efficiency of Sesame (Sesamum indicum L. Affected by Different Irrigation Regimes in Mashhad Condition

    Directory of Open Access Journals (Sweden)

    A Koocheki

    2016-02-01

    Full Text Available Introduction Plant association with mycorrhiza has been considered as one of the options to improve input efficiency particularly for water and nutrient - (Allen and Musik, 1993; Bolan, 1991. This has been due to kncreasing the absorbing area of the root and therefore better contact with water and nutrients. Inoculation with mycorrhiza enhances nutrient uptake with low immobility such as phosphorus and solphur-, improve association and could be an option to drought and other environmental abnormalities such as salinity (Rice et al., 2002. Moreover, higher water use efficiency (WUE for crops -has been reported in the literatures (Sekhara and Reddy, 1993.The sustainable use of scarce water resources in Iran is a priority for agricultural development. The pressure of using water in agriculture sector is increasing, so creating ways to improve water-use efficiency and taking a full advantage of available water are crucial. Water stress reduce crop yield by impairing the growth of crop canopy and biomass. Scheduling water application is very crucial for efficient use of drip irrigation system, as excessive irrigation reduces yield, while inadequate irrigation causes water stress and reduces production. The aim of present study was to evaluate the symbiotic effect of mycorrhiza on yield, yield components and water use efficiency of sesame under different irrigation regimes in Mashhad. Material and Methods In order to investigate the impact of inoculation with two species of Arbuscular mycorrhiza fungi on yield, yield components and water use efficiency (WUE of sesame (Sesamum indicum L. under different irrigation regimes, an experiment was conducted as split plot based on a randomized complete block design with three replications during two growing seasons 2009-2010 and 2010-2011 at the Agricultural Research Station, College of Agriculture, Ferdowsi University of Mashhad.. The experimental factors were three irrigation regimes include 2000, 3000 and

  17. Nitrogen transfer via VA mycorrhiza hyphae link between roots of red clover

    International Nuclear Information System (INIS)

    Zhang Junling; Li Xiaolin; Yang Zhifu

    1997-01-01

    Five compartments with a air gap was designed to examine underground N transfer via VAM hyphae link between roots of red clover. 15 N was injected into the root compartment for donor plant 4 weeks after planting. Plants were harvested 6 weeks afterwards. The experiment had four treatments: two N levels (receiver root compartment); mycorrhiza and non-mycorrhiza treatment (B compartment), and each with four replicates. It was demonstrated that there was no significant difference in 15 N abundance in receiver red clover regardless of the inoculation of mycorrhiza fungi and nitrogen fertilization. Both shoot and root dry weight of receiver plants were not affected too, however, plant P and N nutrient status got better under this condition

  18. Effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus application rates

    Directory of Open Access Journals (Sweden)

    S. Fatih Ergin

    2016-10-01

    Full Text Available In this study, effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus fertilization rates were investigated. Phosphorus were added into growing media as 0, 50, 100 and 200 mg P2O5/kg with and without mycorrhiza applications. Phosphorus applications significantly increased yield criteria of lettuce according to the control treatment statistically. Mycorrhiza application also significantly increased plant diameter, plant dry weight and phosphor uptake by plant. The highest phosphorus uptakes by plants were determined in 200 mg P2O5/kg treatments as 88.8 mg P/pot with mycorrhiza and 83.1 mg P/pot without mycorrhiza application. In the control at 0 doses of phosphorus with mycorrhiza treatment, phosphorus uptake (69.9 mg P/pot, edible weight (84.36 g, dry weight (8.64 g and leaf number (28 of lettuce were higher than that (47.7 mg P/pot, 59.33 g, 6.75 g and 20, respectively in the control without mycorrhiza application. It was determined that mycorrhiza had positive effect on growth criteria and phosphorus nutrition by lettuce plant, and this effect decreased at higher phosphorus application rates.

  19. Enhanced urinary bladder and liver carcinogenesis in male CD1 mice exposed to transplacental inorganic arsenic and postnatal diethylstilbestrol or tamoxifen

    International Nuclear Information System (INIS)

    Waalkes, Michael P.; Liu Jie; Ward, Jerrold M.; Diwan, Bhalchandra A.

    2006-01-01

    Pregnant CD1 mice received 85 ppm arsenite in the drinking water from gestation day 8 to 18, groups (n = 35) of male offspring were subsequently injected on postpartum days 1 through 5 with diethylstilbestrol (DES; 2 μg/pup/day) or tamoxifen (TAM; 10 μg/pup/day), and tumor formation was assessed over 90 weeks. Arsenic alone increased hepatocellular carcinoma (14%), adenoma (23%) and total tumors (31%) compared to control (0, 2 and 2%, respectively). Arsenic alone also increased lung adenocarcinoma, adrenal cortical adenoma and renal cystic tubular hyperplasia compared to control. Compared to arsenic alone, arsenic plus DES increased liver tumor incidence in mice at risk 2.2-fold and increased liver tumor multiplicity (tumors/liver) 1.8-fold. The treatments alone did not impact urinary bladder carcinogenesis, but arsenic plus TAM significantly increased formation of urinary bladder transitional cell tumors (papilloma and carcinoma; 13%) compared to control (0%). Urinary bladder proliferative lesions (combined tumors and hyperplasia) were also increased by arsenic plus TAM (40%) or arsenic plus DES (43%) compared to control (0%) or the treatments alone. Urinary bladder proliferative lesions occurred in the absence of any evidence of uroepithelial cytotoxic lesions. Urinary bladder lesions and hepatocellular carcinoma induced by arsenic plus TAM and/or DES overexpressed estrogen receptor-α, indicating that aberrant estrogen signaling may have been a factor in the enhanced carcinogenic response. Thus, in male CD1 mice, gestational arsenic exposure alone induced liver adenoma and carcinoma, lung adenocarcinoma, adrenal adenoma and renal cystic hyperplasia. Furthermore, DES enhanced transplacental arsenic-induced hepatocarcinogenesis. In utero arsenic also initiated urinary bladder tumor formation when followed by postnatal TAM and uroepithelial proliferative lesions when followed by TAM or DES

  20. Effectiveness of cow manure and mycorrhiza on the growth of soybean

    Science.gov (United States)

    Muktiyanta, M. N. A.; Samanhudi; Yunus, A.; Pujiasmanto, B.; Minardi, S.

    2018-03-01

    Soybean is one of the major food crop commodities in Indonesia. The needs of soybean each year is always increasing, but the the production rate is low. The research aimed to know the influence of treatment doses of cow manure and mycorrhiza towards growth and yield of soybeans. This research was conducted using Randomized Complete Block Design with two factors. The first factor is the dose of cow manure: S0 (0 g/plot), S1 (781.25 g/plot), S2 (1562.5 g/plot), and S3 (2343.75 g/plot). The second factor is the dose of mycorrhiza: M0 (0 g/plot), M1 (100 g/plot), and M2 (200 g/plot). The observed parameters is plant height, the number of productive branches, weight of 100 seeds, root length, fresh weight of biomass, dry weight of biomass, conversion calculation results of soybeans per hectacre and the percentage of roots infected with mycorrhiza. Data were analyzed with ANOVA at 5% significance level, continued with Duncan test at 5% confidence level. The results showed that no interaction between the two treatments. Doses of cow manure provides significant influence to plant height and the length of the root. Whereas, the doses of mycorrhiza provides significant effect to the number of productive branch, weight of 100 seeds, dry weight of biomass, and the conversion of soybean yield per hectare.

  1. Nicotinamide enhances repair of arsenic and ultraviolet radiation-induced DNA damage in HaCaT keratinocytes and ex vivo human skin.

    Directory of Open Access Journals (Sweden)

    Benjamin C Thompson

    Full Text Available Arsenic-induced skin cancer is a significant global health burden. In areas with arsenic contamination of water sources, such as China, Pakistan, Myanmar, Cambodia and especially Bangladesh and West Bengal, large populations are at risk of arsenic-induced skin cancer. Arsenic acts as a co-carcinogen with ultraviolet (UV radiation and affects DNA damage and repair. Nicotinamide (vitamin B3 reduces premalignant keratoses in sun-damaged skin, likely by prevention of UV-induced cellular energy depletion and enhancement of DNA repair. We investigated whether nicotinamide modifies DNA repair following exposure to UV radiation and sodium arsenite. HaCaT keratinocytes and ex vivo human skin were exposed to 2μM sodium arsenite and low dose (2J/cm2 solar-simulated UV, with and without nicotinamide supplementation. DNA photolesions in the form of 8-oxo-7,8-dihydro-2'-deoxyguanosine and cyclobutane pyrimidine dimers were detected by immunofluorescence. Arsenic exposure significantly increased levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine in irradiated cells. Nicotinamide reduced both types of photolesions in HaCaT keratinocytes and in ex vivo human skin, likely by enhancing DNA repair. These results demonstrate a reduction of two different photolesions over time in two different models in UV and arsenic exposed cells. Nicotinamide is a nontoxic, inexpensive agent with potential for chemoprevention of arsenic induced skin cancer.

  2. Enhancing arsenic removal from groundwater at household level with naturally occurring iron

    Directory of Open Access Journals (Sweden)

    Anitha Kumari Sharma

    2016-06-01

    Full Text Available A supply of drinking water low in Arsenic (As prevents arsenic poisoning. The presence of high concentrations of iron (Fe in groundwater under the alluvial plains of the large rivers in Southeast Asia is a prerequisite for the simple removal of As. This study investigated the mechanisms and possibilities for enhancing As removal with naturally occurring Fe in a reliable, low cost and sustainable way. The results of the study show that As removal with Fe is greatly enhanced by the addition of an oxidizing agent (preferably KMnO4 immediately after the pumping of groundwater. Further enhancement of As removal in the presence of Fe can be achieved by adding a small volume of a concentrated basic solution of MnO4- and AlO2-, which has a combined oxidation, coagulation and buffering capacity. Best results were obtained when this solution was mixed with the groundwater immediately after its pumping until a pale pink color appeared. Maximum required reaction time was 10 minutes and subsequent filtration of the water was able to reduce the As concentration to near zero. Concentrations of MnO4- and AlO2- can be varied in the solution to achieve sufficient As removal to suit different Fe/As ratios and the presence of interfering co-occurring anions.

  3. Effects of water deficit and mycorrhizae on grain yield, reproductive and physiological traits of corn hybrids

    Directory of Open Access Journals (Sweden)

    Mikail Nordokht

    2018-06-01

    Full Text Available Increasing crop production to ensure future food security while reducing environmental pressure on agro-ecosystems requires improved water and nutrient use efficiency. the arid and semiarid regions of the world lack of sufficient water supply is the major problem for corn cultivation and is a restriction for its production, so studies on the growth limitation and germination of corn seeds under drought conditions seems very necessary. The effects of drought on plant growth depend on several factors such as plant genetic resistance, stage of growth and duration of plant expose to drought. The AMF are playing a vital role in sustainable agriculture because they enhance plant water relations, which improve the drought resistance of host plants. It is important to increase our understanding of AM fungal and maize genotype interactions and water condition on the symbiosis, and on the physiology and nutritional status of maize plants. Thus Mycorrhizae application and choosing suitable cultivar are of simple managements in decreasing drought effect. This investigation had done in order to investigate effect of irrigation regimes (irrigation after 70, 110 and 150 mm evaporaation from evaporate basin, Mycorrhizae (non application and application of Mycorrhizae and cultivar (704 and 640 on growth and yield of maize. A split factorial experiment based on randomized complete block design with three replications was conducted during growing season of 2015 at Islamic Azad University, Malekan Branch, Plots were then furrow irrigated in the mornings every week. Each block was including 12 plots. The size of each plot was 3.5m×4m, and there was in each plot, 5 rows with a distance of 75 cm, and the length of 4 m. The distance between plots was selected 150 cm, and the distance between blocks was selected 3 m. By mid August an area of 2.5 m from 3 line of plot area was separately harvested and traits were evaluated. MSTAT-C and EXCEL were used to analyze data

  4. Small System Use of a Solid Arsenic Oxidizing Media in Place of Chemical Oxidation to Enhance Arsenic Removals

    Science.gov (United States)

    As part of the USEPA Arsenic Demonstration Program, an arsenic removal adsorptive media treatment system (10 gpm) was installed at Head Start School in Buckeye Lake, Ohio on June 28, 2006. The source water (ground water) contained around 20 µg/L of arsenic, existing predominatel...

  5. Uptake and speciation of selenium in garlic cultivated in soil amended with symbiotic fungi (mycorrhiza) and selenate

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Lobinski, R.; Burger-Meyer, K.

    2006-01-01

    The scope of the work was to investigate the influence of selenate fertilisation and the addition of symbiotic fungi (mycorrhiza) to soil on selenium and selenium species concentrations in garlic. The selenium species were extracted from garlic cultivated in experimental plots by proteolytic...... in garlic. The selenium content in garlic, which was analysed by ICP-MS, showed that addition of mycorrhiza to the natural soil increased the selenium uptake by garlic tenfold to 15 mu g g(-1) (dry mass). Fertilisation with selenate and addition of mycorrhiza strongly increased the selenium content...... of soil by mycorrhiza and/or by selenate increased the content of selenium but not the distribution of detected selenium species in garlic. Finally, the use of two-dimensional HPLC (size exclusion followed by reversed-phase) allowed the structural characterisation of gamma...

  6. A Phytoremediation Strategy for Arsenic

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2005-06-01

    A Phytoremediation Strategy for Arsenic Progress Report May, 2005 Richard B. Meagher Principal Investigator Arsenic pollution affects the health of several hundred millions of people world wide, and an estimated 10 million Americans have unsafe levels of arsenic in their drinking water. However, few environmentally sound remedies for cleaning up arsenic contaminated soil and water have been proposed. Phytoremediation, the use of plants to extract and sequester environmental pollutants, is one new technology that offers an ecologically sound solution to a devastating problem. We propose that it is less disruptive to the environment to harvest and dispose of several thousand pounds per acre of contaminated aboveground plant material, than to excavate and dispose of 1 to 5 million pounds of contaminated soil per acre (assumes contamination runs 3 ft deep). Our objective is to develop a genetics-based phytoremediation strategy for arsenic removal that can be used in any plant species. This strategy requires the enhanced expression of several transgenes from diverse sources. Our working hypothesis is that organ-specific expression of several genes controlling the transport, electrochemical state, and binding of arsenic will result in the efficient extraction and hyperaccumulation of arsenic into aboveground plant tissues. This hypothesis is supported by theoretical arguments and strong preliminary data. We proposed six Specific Aims focused on testing and developing this arsenic phytoremediation strategy. During the first 18 months of the grant we made significant progress on five Specific Aims and began work on the sixth as summarized below. Specific Aim 1: Enhance plant arsenic resistance and greatly expand sinks for arsenite by expressing elevated levels of thiol-rich, arsenic-binding peptides. Hyperaccumulation of arsenic depends upon making plants that are both highly tolerant to arsenic and that have the capacity to store large amounts of arsenic aboveground

  7. [Response of arbuscular mycorrhizal fungal lipid metabolism to symbiotic signals in mycorrhiza].

    Science.gov (United States)

    Tian, Lei; Li, Yuanjing; Tian, Chunjie

    2016-01-04

    Arbuscular mycorrhizal (AM) fungi play an important role in energy flow and nutrient cycling, besides their wide distribution in the cosystem. With a long co-evolution, AM fungi and host plant have formed a symbiotic relationship, and fungal lipid metabolism may be the key point to find the symbiotic mechanism in arbusculart mycorrhiza. Here, we reviewed the most recent progress on the interaction between AM fungal lipid metabolism and symbiotic signaling networks, especially the response of AM fungal lipid metabolism to symbiotic signals. Furthermore, we discussed the response of AM fungal lipid storage and release to symbiotic or non-symbiotic status, and the correlation between fungal lipid metabolism and nutrient transfer in mycorrhiza. In addition, we explored the feedback of the lipolysis process to molecular signals during the establishment of symbiosis, and the corresponding material conversion and energy metabolism besides the crosstalk of fungal lipid metabolism and signaling networks. This review will help understand symbiotic mechanism of arbuscular mycorrhiza fungi and further application in ecosystem.

  8. Production of fungal and bacterial growth modulating secondary metabolites is widespread among mycorrhiza-associated streptomycetes

    Science.gov (United States)

    2012-01-01

    Background Studies on mycorrhiza associated bacteria suggest that bacterial-fungal interactions play important roles during mycorrhiza formation and affect plant health. We surveyed Streptomyces Actinobacteria, known as antibiotic producers and antagonists of fungi, from Norway spruce mycorrhizas with predominantly Piloderma species as the fungal partner. Results Fifteen Streptomyces isolates exhibited substantial variation in inhibition of tested mycorrhizal and plant pathogenic fungi (Amanita muscaria, Fusarium oxysporum, Hebeloma cylindrosporum, Heterobasidion abietinum, Heterobasidion annosum, Laccaria bicolor, Piloderma croceum). The growth of the mycorrhiza-forming fungus Laccaria bicolor was stimulated by some of the streptomycetes, and Piloderma croceum was only moderately affected. Bacteria responded to the streptomycetes differently than the fungi. For instance the strain Streptomyces sp. AcM11, which inhibited most tested fungi, was less inhibitory to bacteria than other tested streptomycetes. The determined patterns of Streptomyces-microbe interactions were associated with distinct patterns of secondary metabolite production. Notably, potentially novel metabolites were produced by strains that were less antagonistic to fungi. Most of the identified metabolites were antibiotics (e.g. cycloheximide, actiphenol) and siderophores (e.g. ferulic acid, desferroxiamines). Plant disease resistance was activated by a single streptomycete strain only. Conclusions Mycorrhiza associated streptomycetes appear to have an important role in inhibiting the growth of fungi and bacteria. Additionally, our study indicates that the Streptomyces strains, which are not general antagonists of fungi, may produce still un-described metabolites. PMID:22852578

  9. Evaluation of Two Mycorrhiza Species and Nitroxin on Yield and Yield Components of Garlic (Allium sativum L. in an Ecological Agroecosystem

    Directory of Open Access Journals (Sweden)

    P Rezvani Moghaddam

    2016-02-01

    Full Text Available Introduction Maintenance of soil fertility is one of the most important issues affecting the sustainability of food production. The application of ecological inputs such as mycorrhiza and biofertilizers are one of those approaches which are needed to maintain soil fertility Biofetilizers include different types of free living organisms that convert unavailable nutrients to available forms and enhance root development and better seed germination. Plant growth promoting rhizobacteria (PGPR occupy the rhizosphere of many plant species and have beneficial effects on the host plant. They may directly and indirectly influence the plant growth. A direct mechanism would be to increase plant growth by supplying the plant with nutrients and hormones. Indirect mechanisms, on the other hand, include reduced susceptibility to diseases and acting as a form of defense referred to as induces systematic resistance. Mycorrhiza arbuscular fungi are other coexist microorganisms that improve soil fertility, nutrients cycling and agroecosystem health. Mycorrhizal fungi are the most abundant organisms in agricultural soils. Many researchers have pointed to the positive roles of mycorrhizal fungi on plants growth characteristics. Arbuscular mycorrhizas are found in 85% of all plant families and occur in many crop species. Mineral nutrients such as potassium, calcium, copper, zinc and iron are assimilated more quickly and in greater amounts by mycorrhizal plants. Arbuscular mycorrhizal inoculation has also been shown to increase plant resistance of pathogen attack. Garlic (Allium sativum L. is a very powerful medicinal plant that is often underestimated. Garlic is easy to grow and can be grown year-round in any mild climates. Garlic cloves are used for consumption (row and cooked or for medicinal purposes. They have a characteristic pungent, spicy flavor that mellows and sweetens considerably with cooking. Despite of many studies on the effects of mycorrhiza and

  10. Evaluation of integrated management of organic manure application and mycorrhiza inoculation on growth criteria, qualitative and essential oil yield of hyssop (Hyssopus officinalis L. under Mashhad climatic conditions

    Directory of Open Access Journals (Sweden)

    J. Shabahang

    2016-05-01

    Full Text Available In order to study impacts of organic manure levels and inoculation with mycorrhiza fungi on growth, quantitative and qualitative yield of hyssop (Hyssopus officinalis L., a field experiment was conducted as factorial based on a randomized complete block design with three replications at the Agricultural Research Station, Ferdowsi University of Mashhad, during two growing seasons of 2009-2010 and 2010-2011. Mycorhiza inoculation (with and without inoculation and five levels of organic manure as decomposed cow manure (zero, 10, 20, 30 and 40 t.ha-1 were considered as treatments. Plant height, canopy diameter, leaf to shoot ratio, shoot dry weight, essential oil content and essential oil yield of hyssop were measured and calculated accordingly. The results showed that the simple and interaction effects between organic manure and mycorrhiza were significant (p≤0.01 on plant height, canopy diameter, leaf to stem ratio, shoot dry weight and essential oil content and yield of hyssop. By increasing organic manure level from zero to 30 t.ha-1 enhanced shoot dry weight and essential oil yield of hyssop up to 127 and 43%, respectively. Whereas by increasing organic manure level up to 40 t.ha-1 improved these traits up to 12 and 24%, respectively. Mycorrhiza inoculation enhanced shoot dry weight and essential oil yield up to 19 and 14%, respectively. The second year, growth of hyssop plants due to suitable establishment and more availability of nutrients were higher than the first year. Organic manure enhanced growth and yield of hyssop due to availability of nutrients and improvement in soil characteristics. Mycorrhiza inoculation promoted growth and yield of this valuable medicinal plant because of root development and nutrient availability particularly phosphorus.

  11. Effect of arbuscular mycorrhiza on the growth and development of micropropagated Annona cherimola plants

    Directory of Open Access Journals (Sweden)

    Concepcion Azcón-Aguilar

    1994-05-01

    Full Text Available Annona cherimola Mill., cherimoya, is a tropical plantation crop of interest in fruit culture. Micropropagation techniques have been developed due to the need to increase productivity through clonal selection. Because of the mycorrhizal dependence exhibited by this crop for optimal growth and the recognized role of mycorrhiza establishment for the survival and development of most of the plants produced in vitro, the effect of mycorrhiza inoculation on the development of micropropagated plants of Annona cherimola was investigated. Mycorrhizal inoculation was assayed at two different stages of the micropropagation process: (i immediately after the in vitro phase, before starting the acclimatization period, and (ii after the acclimatization phase, before starting the post-acclimatization period under greenhouse conditions. Plantlet survival was about 50 % after the acclimatization period. Plant growth and development profited remarkably from mycorrhiza establishment. Most of the arbuscular mycorrhizal fungi (AMF assayed greatly increased shoot and root biomass and leaf area. Micropropagated Annona plants seem to be more dependent on mycorrhiza formation for optimal growth than plants derived from seeds. The greatest effects of AMF on plant growth were observed when they were introduced after the acclimatization period.

  12. Blockage of JNK pathway enhances arsenic trioxide-induced apoptosis in human keratinocytes

    International Nuclear Information System (INIS)

    Huang, H.-S.; Liu, Z.-M.; Hong, D.-Y.

    2010-01-01

    Arsenic is well known as a carcinogen predisposing humans to some severe diseases and also as an effective medicine for treating acute promyelocytic leukemia, syphilis, and psoriasis. Multiple active mechanisms, including cell cycle arrest and apoptosis, have been proposed in therapy; however, the opposing effects of arsenic remain controversial. Our previous study found that arsenic trioxide (ATO)-induced activation of p21 WAF1/CIP1 (p21) led to A431 cell death through the antagonistic effects of the signaling of ERK1/2 and JNK1. In the current study, the inhibitory effects of JNK1 on ATO-induced p21 expression were explored. Over-expression of JNK1 in A431 cells could inhibit p21 expression, which was associated with HDAC1 and TGIF. Using the GST pull-down assay and fluorescence resonance energy transfer analysis, N-terminal domain (amino acids 1-108) of TGIF, critical to its binding with c-Jun, was found. Using reporter assays, requirement of the C-terminal domain (amino acids 138-272) of TGIF to suppress ATO-induced p21 expression was observed. Thus, the domains of TGIF that carried out its inhibitory effects on p21 were identified. Finally, treatment with JNK inhibitor SP600125 could enhance ATO-induced apoptosis of HaCaT keratinocytes by using flow cytometry.

  13. Heavy metal distribution in Suillus luteus mycorrhizas - as revealed by micro-PIXE analysis

    Science.gov (United States)

    Turnau, K.; Przybyłowicz, W. J.; Mesjasz-Przybyłowicz, J.

    2001-07-01

    Suillus luteus/Pinus sylvestris mycorrhizas, collected from zinc wastes in Southern Poland, were selected as potential biofilters on the basis of earlier studies carried out with energy dispersive spectrometry (EDS) microanalytical system coupled to scanning electron microscope (SEM) and transmission electron microscope (TEM). Using the National Accelerator Centre (NAC) nuclear microprobe, elemental concentrations in the ectomycorrhiza parts were for the first time estimated quantitatively. Micro-proton-induced X-ray emission (PIXE) true elemental maps from freeze-dried and chemically fixed mycorrhizas revealed strong accumulation of Ca, Fe, Zn and Pb within the fungal mantle and in the rhizomorph. Vascular tissue was enriched with P, S and K, while high concentrations of Si and Cl were present in the endodermis. Cu was the only element showing elevated concentrations in the cortex region. Elemental losses and redistributions were found in mycorrhizas prepared by chemical fixation. Some problems related to elemental imaging are discussed.

  14. Heavy metal distribution in Suillus luteus mycorrhizas - as revealed by micro-PIXE analysis

    International Nuclear Information System (INIS)

    Turnau, K.; Przybylowicz, W.J.; Mesjasz-Przybylowicz, J.

    2001-01-01

    Suillus luteus/Pinus sylvestris mycorrhizas, collected from zinc wastes in Southern Poland, were selected as potential biofilters on the basis of earlier studies carried out with energy dispersive spectrometry (EDS) microanalytical system coupled to scanning electron microscope (SEM) and transmission electron microscope (TEM). Using the National Accelerator Centre (NAC) nuclear microprobe, elemental concentrations in the ectomycorrhiza parts were for the first time estimated quantitatively. Micro-proton-induced X-ray emission (PIXE) true elemental maps from freeze-dried and chemically fixed mycorrhizas revealed strong accumulation of Ca, Fe, Zn and Pb within the fungal mantle and in the rhizomorph. Vascular tissue was enriched with P, S and K, while high concentrations of Si and Cl were present in the endodermis. Cu was the only element showing elevated concentrations in the cortex region. Elemental losses and redistributions were found in mycorrhizas prepared by chemical fixation. Some problems related to elemental imaging are discussed

  15. Nitrate transport processes in Fagus-Laccaria-mycorrhizae

    NARCIS (Netherlands)

    Kreuzwieser, J; Stulen, [No Value; Wiersema, P; Vaalburg, W; Rennenberg, H

    2000-01-01

    The contribution of influx and efflux of NO3- on NO3- net uptake has been studied in excised mycorrhizae of 18-20 week old beech (Fagus sylvatica L.) trees. Net uptake rates of NO3- followed uniphasic Michaelis-Menten kinetics in the concentration range between 10 mu M and 1.0 mM external NO3-, with

  16. Production of fungal and bacterial growth modulating secondary metabolites is widespread among mycorrhiza-associated streptomycetes

    Directory of Open Access Journals (Sweden)

    Schrey Silvia D

    2012-08-01

    Full Text Available Abstract Background Studies on mycorrhiza associated bacteria suggest that bacterial-fungal interactions play important roles during mycorrhiza formation and affect plant health. We surveyed Streptomyces Actinobacteria, known as antibiotic producers and antagonists of fungi, from Norway spruce mycorrhizas with predominantly Piloderma species as the fungal partner. Results Fifteen Streptomyces isolates exhibited substantial variation in inhibition of tested mycorrhizal and plant pathogenic fungi (Amanita muscaria, Fusarium oxysporum, Hebeloma cylindrosporum, Heterobasidion abietinum, Heterobasidion annosum, Laccaria bicolor, Piloderma croceum. The growth of the mycorrhiza-forming fungus Laccaria bicolor was stimulated by some of the streptomycetes, and Piloderma croceum was only moderately affected. Bacteria responded to the streptomycetes differently than the fungi. For instance the strain Streptomyces sp. AcM11, which inhibited most tested fungi, was less inhibitory to bacteria than other tested streptomycetes. The determined patterns of Streptomyces-microbe interactions were associated with distinct patterns of secondary metabolite production. Notably, potentially novel metabolites were produced by strains that were less antagonistic to fungi. Most of the identified metabolites were antibiotics (e.g. cycloheximide, actiphenol and siderophores (e.g. ferulic acid, desferroxiamines. Plant disease resistance was activated by a single streptomycete strain only. Conclusions Mycorrhiza associated streptomycetes appear to have an important role in inhibiting the growth of fungi and bacteria. Additionally, our study indicates that the Streptomyces strains, which are not general antagonists of fungi, may produce still un-described metabolites.

  17. Effects of Tissue Culture and Mycorrhiza Applications in Organic Farming on Concentrations of Phytochemicals and Antioxidant Capacities in Ginger (Zingiber officinale Roscoe) Rhizomes and Leaves.

    Science.gov (United States)

    Min, Byungrok R; Marsh, Lurline E; Brathwaite, Keegan; Daramola, Adebola O

    2017-04-01

    Tissue culture and mycorrhiza applications can provide disease-free seedlings and enhanced nutrient absorption, respectively, for organic farming. Ginger (Zingiber officinale Roscoe) is rich in phytochemicals and has various health-protective potentials. This study was aimed at determining effects of tissue culture and mycorrhiza applications alone or in combinations in organic farming on phytochemical contents (total phenolics and flavonoids [TP and TF, respectively], gingerol and shogaol homologues, phenolic acids, and carotenoids) and antioxidant capacities (DPPH [2,2-diphenyl-1-picrylhydrazyl] radical scavenging, oxygen radical absorbance (ORAC), and iron-chelating capacities [ICC]) in solvent-extractable (Free) and cell-wall-matrix-bound (Bound) fractions of ginger rhizome and Free fraction of the leaves in comparison with non-organics. Concentrations of the phytochemicals and antioxidant capacities, except for carotenoids and ICC, were significantly higher in organic ginger rhizomes and leaves than in non-organics regardless of the fractions and treatments (P < 0.05). Mycorrhiza application in organic farming significantly increased levels of TP, TF, gingerols, and ORAC in the Free fraction of the rhizome (P < 0.05). Furthermore, the combined application of tissue culture and mycorrhiza significantly increased concentrations of TF and gingerols and ORAC in the Free fraction of the rhizome (P < 0.05), suggesting their synergistic effects. Considerable amounts of phenolics were found in the Bound fractions of the rhizomes. Six-gingerol, ferulic acid, and lutein were predominant ones among gingerols, phenolic acids, and carotenoids, respectively, in ginger rhizomes. The results suggest that organic farming with mycorrhiza and tissue culture applications can increase concentrations of phytochemicals and antioxidant capacities in ginger rhizomes and leaves and therefore improve their health-protective potentials. © 2017 Institute of Food Technologists®.

  18. Effects of mycorrhiza inoculation and different irrigation levels on yield, yield components and essential oil contents of fennel (Foeniculum vulgare Mill. and ajwain (Trachyspermum ammi L.

    Directory of Open Access Journals (Sweden)

    A Koocheki

    2016-05-01

    Full Text Available Introduction Fertilizers are the key components which provide plant nutrients' needs in recent years (Omid Jangir & Sing, 1996; Kapoor et al., 2007. In many cases, using chemical fertilizers has different negative environmental effects such as soil, water and air pollution, which increase environmental hazardous and production costs (Jangir & Sing, 1996; Kapoor et al., 2007. Biological activities are markedly enhanced by microbial interactions in the rhizosphere of plants (Kapoor et al., 2007. Many investigators have successfully used mycorrhiza to increase the availability of immobilized phosphate and thus minimize the use of mineral fertilizers. Arbuscular Mycorrhizal Fungi (AMF can better enable a plant to withstand environmental stresses such as drought and salinity. AMF interacts with pathogens and other rhizosphere inhabitants which affect plant health and nutrition. More importantly, mycorrhizal fungi are capable of dissolving weakly soluble soil minerals, especially phosphate, by releasing acids or increasing CO2 partial pressure (Gupta et al., 2002; Gosling et al., 2006; Kapoor et al., 2007. Therefore, they have the ability to enhance host plant uptake of relatively immobile nutrients particularly P, S and Zn. Limited water supply is also another major environmental constraint in the productivity of crop and medicinal plants. Moisture deficiency induces various physiological and metabolic responses such as stomatal closure, decline in growth rate and photosynthesis (Flexas and Medrano, 2002. The results of Baher et al. (2002 showed that greater soil water stress decreased plant height and total fresh and dry weight of Satureja hortensis. Materials and Methods In order to study the effects of mycorrhiza inoculation and different irrigation levels on the growth, quantitative and qualitative yield of fennel (Foeniculum vulgare Mill. and ajwain (Trachyspermum ammi L., a field experiment was conducted as factorial based on randomized

  19. An attempt to electrically enhance phytoremediation of arsenic contaminated water

    KAUST Repository

    Kubiak, Jan J.; Khankhane, Premraj J.; Kleingeld, Pieter J.; Lima, Ana T.

    2012-01-01

    Water polluted with arsenic presents a challenge for remediation. A combination of phyto- and electro-remediation was attempted in this study. Four tanks were setup in order to assess the arsenic removal ability of the two methods separately

  20. Vertical distribution and temperature relations of sheathing mycorrhizas of Betula spp. growing on coal spoil

    Energy Technology Data Exchange (ETDEWEB)

    Ingleby, K.; Last, F.T.; Mason, P.A.

    1985-10-01

    Naturally-occurring fine roots (<2 mm dia.) of Betula spp. were sampled to a depth of 30 cm at seven locations on each of two transects across a heap of coal spoil in parts subject to after-burn. In the top 20 cm of substrate, 87% of the root pieces occurred. Irrespective of depth, sheathing mycorrhizas were found on 83% of the roof pieces. While the percentages of Paxillus-type mycorrhizas decreased with soil depth, those of a Scleroderma-type significantly increased. Total numbers of mycorrhizas counted at the end-of-season were independent of substrate temperatures. However, numbers of Paxillus-type mycorrhizas were inversely related to both annual mean and spring substrate temperatures, whereas those of the Scleroderma- type were directly related. Vegetative cultures of Scleroderma citrinum grew on an agar medium at 30 C, whereas those of Paxillus involutus did not; at lower temperatures the two fungi responded similarly to temperature changes. The evidence suggests that the observed patterns of mycorrhizal development reflect the changing competitive abilities of Scleroderma and Paxillus and/or host influences at different temperatures in the range 8-16 C.

  1. Enhanced carcinogenicity by coexposure to arsenic and iron and a novel remediation system for the elements in well drinking water.

    Science.gov (United States)

    Kumasaka, Mayuko Y; Yamanoshita, Osamu; Shimizu, Shingo; Ohnuma, Shoko; Furuta, Akio; Yajima, Ichiro; Nizam, Saika; Khalequzzaman, Md; Shekhar, Hossain U; Nakajima, Tamie; Kato, Masashi

    2013-03-01

    Various carcinomas including skin cancer are explosively increasing in arsenicosis patients who drink arsenic-polluted well water, especially in Bangladesh. Although well drinking water in the cancer-prone areas contains various elements, very little is known about the effects of elements except arsenic on carcinogenicity. In order to clarify the carcinogenic effects of coexposure to arsenic and iron, anchorage-independent growth and invasion in human untransformed HaCaT and transformed A431 keratinocytes were examined. Since the mean ratio of arsenic and iron in well water was 1:10 in cancer-prone areas of Bangladesh, effects of 1 μM arsenic and 10 μM iron were investigated. Iron synergistically promoted arsenic-mediated anchorage-independent growth in untransformed and transformed keratinocytes. Iron additionally increased invasion in both types of keratinocytes. Activities of c-SRC and ERK that regulate anchorage-independent growth and invasion were synergistically enhanced in both types of keratinocytes. Our results suggest that iron promotes arsenic-mediated transformation of untransformed keratinocytes and progression of transformed keratinocytes. We then developed a low-cost and high-performance adsorbent composed of a hydrotalcite-like compound for arsenic and iron. The adsorbent rapidly reduced concentrations of both elements from well drinking water in cancer-prone areas of Bangladesh to levels less than those in WHO health-based guidelines for drinking water. Thus, we not only demonstrated for the first time increased carcinogenicity by coexposure to arsenic and iron but also proposed a novel remediation system for well drinking water.

  2. Surface-enhanced raman spectroscopy substrate for arsenic sensing in groundwater

    Science.gov (United States)

    Yang, Peidong; Mulvihill, Martin; Tao, Andrea R.; Sinsermsuksakul, Prasert; Arnold, John

    2015-06-16

    A surface-enhanced Raman spectroscopy (SERS) substrate formed from a plurality of monolayers of polyhedral silver nanocrystals, wherein at least one of the monolayers has polyvinypyrrolidone (PVP) on its surface, and thereby configured for sensing arsenic is described. Highly active SERS substrates are formed by assembling high density monolayers of differently shaped silver nanocrystals onto a solid support. SERS detection is performed directly on this substrate by placing a droplet of the analyte solution onto the nanocrystal monolayer. Adsorbed polymer, polyvinypyrrolidone (PVP), on the surface of the nanoparticles facilitates the binding of both arsenate and arsenite near the silver surface, allowing for highly accurate and sensitive detection capabilities.

  3. Effect of mycorrhizas application on plant growth and nutrient uptake in cucumber production under field conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ortas, I.

    2010-07-01

    Mycorrhizas application in horticultural production in the Eastern Mediterranean region of Turkey has been studied under field conditions for several years. The effects of different arbuscular mycorrhizal fungi (AMF) have been evaluated under field conditions for cucumber production. The parameters measured were seedling survival, plant growth and yield, and root colonization. In 1998 and 1999, Glomus mosseae and Glomus etunicatum inoculated cucumber seedlings were treated with and without P (100 kg P2O5 ha-1) application. A second experiment was set up to evaluate the response of cucumber to the inoculation with a consortia of indigenous mycorrhizae, G. mosseae, G. etunicatum, Glomus clarum, Glomus caledonium and a mixture of these four species. Inoculated and control non inoculated cucumber seedlings were established under field conditions in 1998, 2001, 2002 and 2004. Seedling quality, seedling survival under field conditions and yield response to mycorrhiza were tested. Fruits were harvested periodically; at blossom, plant leaves and root samples were taken for nutrient content and mycorrhizal colonization analysis respectively. The field experiment results showed that mycorrhiza inoculation significantly increased cucumber seedling survival, fruit yield, P and Zn shoot concentrations. Indigenous mycorrhiza inoculum was successful in colonizing plant roots and resulted in better plant growth and yield. The relative effectiveness of each of the inocula tested was not consistent in the different experiments, although inoculated plants always grew better than control no inoculated. The most relevant result for growers was the increased survival of seedlings. (Author) 20 refs.

  4. Arbuscular mycorrhiza reduces phytoextraction of uranium, thorium and other elements from phosphate rock

    DEFF Research Database (Denmark)

    Roos, Per; Jakobsen, Iver

    2008-01-01

    Uptake of metals from uranium-rich phosphate rock was studied in Medicago truncatula plants grown in symbiosis with the arbuscular mycorrhizal fungus Glomus intraradices or in the absence of mycorrhizas. Shoot concentrations of uranium and thorium were lower in mycorrhizal than in non-mycorrhizal......-fungus uptake systems. The results support the role of arbuscular mycorrhiza as being an important component in phytostabilization of uranium. This is the first study to report on mycorrhizal effect and the uptake and root-to-shoot transfer of thorium from phosphate rock. (c) 2007 Elsevier Ltd. All rights...

  5. Occurrence and succession of mycorrhizas in Alnus incana

    Energy Technology Data Exchange (ETDEWEB)

    Arveby, A.S. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Section of Forest Ecophysiology; Granhall, U. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Microbiology

    1998-12-31

    The occurrence of different mycorrhizas of the grey alder, Alnus incana (L.) Moench., in Sweden was investigated. Root sampling was carried out in planted and natural grey alder stands, representing different soil types, geographical sites, and plant ages. Mycorrhizal infection of roots was found to be frequent at all investigated sites, except for some planted peat bogs, where alders do not occur naturally. At the latter sites, mycorrhizal infection was less frequent and consisted only of ectomycorrhizas. Young trees here were non-mycorrhizal. At all other sites vesicular-arbuscular mycorrhiza (VAM) was found to be the almost exclusive type of mycorrhiza in first-year seedlings. In trees older than one year ectomycorrhiza was the dominating type. In the planted stands up to five years of age no fruitbodies of ectomycorrhizal fungi were found. In such stands the ectomycorrhizas generally had thin, translucent mantles and could be observed only by microscopic examination. In one old plantation (27 years) and in the natural stands sporocarps of several specific `alder fungi` were found. Here, the mycorrhizal root tips had thick, mostly whitish mantles. The Hartig net was in all cases confined to penetration between epidermal cells. Soil collected from one alder site and two non-alder biotopes readily infected grey alder seedlings with Frankia and VAM fungi whereas a peat soil failed to infect seedlings with any symbiont. In vitro inoculation of nodulated seedlings with Glomus mossae (Nicol. and Gerd.) Gerdemann and Trappe resulted in VAM-infection. Simultaneous syntheses with isolates of alder-specific, and other, ectomycorrhizal fungi, using three different methods, failed. On the basis of these results an endomycorrhizal-ectomycorrhizal succession after the first growth season in Alnus incana is concluded. A subsequent succession of ectomycorrhizal species from early-stage to late-stage ones is discussed 58 refs, 3 figs, 2 tabs

  6. An attempt to electrically enhance phytoremediation of arsenic contaminated water

    NARCIS (Netherlands)

    Kubiak, J.J.; Khankhane, P.J.; Kleingeld, P.J.; Lima, A.T.

    2012-01-01

    Water polluted with arsenic presents a challenge for remediation. A combination of phyto- and electro-remediation was attempted in this study. Four tanks were setup in order to assess the arsenic removal ability of the two methods separately and in combination. Lemna minor was chosen for As

  7. Diversity of arbuscular mycorrhiza in the rhizosphere of Cajeput in agroforestry system with different fertilizer management of maize

    Science.gov (United States)

    Parwi; Pudjiasmanto, B.; Purnomo, D.; Cahyani, VR

    2017-11-01

    This study investigated the diversity of arbuscular mycorrhiza in rhizosphere of cajeput with different fertilizer management of maize. This research was conducted by observation on cajeput agroforestry system in Ponorogo that have different fertilizer management of maize: conventional management (CM), universal management (UM) and alternative management (AM1, AM2, and AM3). The result showed that the highest infection of arbuscular mycorrhiza was observed in the plot of AM3, while the lowest colonization was observed in the plot of CM. Infection of arbuscular mycorrhiza in roots cajeput from five fertilizer management, ranging from 32.64% - 63.33%. In all fertilizer management, there were eight species of arbuscular mycorrhiza which five species were Glomus genus, one species was Acaulospora genus and two species were Gigaspora genus. Glomus constrictum was the dominant species in all fertilizer management. Acaulospora favoeta was found only in the plot of AM3. Spore density varies between 150-594 / 100g of soil. The highest spore density was observed in the plot of AM3, while the lowest spore density was observed in the plot of AM1. The highest diversity index value of arbuscular mycorrhiza (Species richness and Shannon-Wiener) was observed in the plot of AM3.

  8. Small Systems Use of a Solid Arsenic Oxidizing Media in Place of Chemical Oxidation to Enhance Arsenic Removal

    Science.gov (United States)

    Presentation provides information on the need to oxidize As III to As V to increase arsenic removal followed by information on the results of an arsenic demonstration project (Plainview CDS) using a solid oxidizing media (Filox) to oxidize As III. The presentation includes a sho...

  9. Atorvastatin ameliorates arsenic-induced hypertension and enhancement of vascular redox signaling in rats

    International Nuclear Information System (INIS)

    Sarath, Thengumpallil Sasindran; Waghe, Prashantkumar; Gupta, Priyanka; Choudhury, Soumen; Kannan, Kandasamy; Pillai, Ayyappan Harikrishna; Harikumar, Sankaran Kutty; Mishra, Santosh Kumar; Sarkar, Souvendra Nath

    2014-01-01

    Chronic arsenic exposure has been linked to elevated blood pressure and cardiovascular diseases, while statins reduce the incidence of cardiovascular disease predominantly by their low density lipoprotein-lowering effect. Besides, statins have other beneficial effects, including antioxidant and anti-inflammatory activities. We evaluated whether atorvastatin, a widely used statin, can ameliorate arsenic-induced increase in blood pressure and alteration in lipid profile and also whether the amelioration could relate to altered NO and ROS signaling. Rats were exposed to sodium arsenite (100 ppm) through drinking water for 90 consecutive days. Atorvastatin (10 mg/kg bw, orally) was administered once daily during the last 30 days of arsenic exposure. On the 91st day, blood was collected for lipid profile. Western blot of iNOS and eNOS protein, NO and 3-nitrotyrosine production, Nox-4 and p22Phox mRNA expression, Nox activity, ROS generation, lipid peroxidation and antioxidants were evaluated in thoracic aorta. Arsenic increased systolic, diastolic and mean arterial blood pressure, while it decreased HDL-C and increased LDL-C, total cholesterol and triglycerides in serum. Arsenic down-regulated eNOS and up-regulated iNOS protein expression and increased basal NO and 3-nitrotyrosine level. Arsenic increased aortic Nox-4 and p22Phox mRNA expression, Nox activity, ROS generation and lipid peroxidation. Further, arsenic decreased the activities of superoxide dismutase, catalase, and glutathione peroxidase and depleted aortic GSH content. Atorvastatin regularized blood pressure, improved lipid profile and attenuated arsenic-mediated redox alterations. The results demonstrate that atorvastatin has the potential to ameliorate arsenic-induced hypertension by improving lipid profile, aortic NO signaling and restoring vascular redox homeostasis. - Highlights: • Arsenic increased systolic, diastolic and mean arterial blood pressure and caused dyslipidemia. • Arsenic increased

  10. Atorvastatin ameliorates arsenic-induced hypertension and enhancement of vascular redox signaling in rats

    Energy Technology Data Exchange (ETDEWEB)

    Sarath, Thengumpallil Sasindran; Waghe, Prashantkumar; Gupta, Priyanka; Choudhury, Soumen; Kannan, Kandasamy [Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, 243122 Bareilly, Uttar Pradesh (India); Pillai, Ayyappan Harikrishna [Division of Animal Biochemistry, Indian Veterinary Research Institute, Izatnagar, 243122 Bareilly, Uttar Pradesh (India); Harikumar, Sankaran Kutty; Mishra, Santosh Kumar [Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, 243122 Bareilly, Uttar Pradesh (India); Sarkar, Souvendra Nath, E-mail: snsarkar1911@rediffmail.com [Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar, 243122 Bareilly, Uttar Pradesh (India)

    2014-11-01

    Chronic arsenic exposure has been linked to elevated blood pressure and cardiovascular diseases, while statins reduce the incidence of cardiovascular disease predominantly by their low density lipoprotein-lowering effect. Besides, statins have other beneficial effects, including antioxidant and anti-inflammatory activities. We evaluated whether atorvastatin, a widely used statin, can ameliorate arsenic-induced increase in blood pressure and alteration in lipid profile and also whether the amelioration could relate to altered NO and ROS signaling. Rats were exposed to sodium arsenite (100 ppm) through drinking water for 90 consecutive days. Atorvastatin (10 mg/kg bw, orally) was administered once daily during the last 30 days of arsenic exposure. On the 91st day, blood was collected for lipid profile. Western blot of iNOS and eNOS protein, NO and 3-nitrotyrosine production, Nox-4 and p22Phox mRNA expression, Nox activity, ROS generation, lipid peroxidation and antioxidants were evaluated in thoracic aorta. Arsenic increased systolic, diastolic and mean arterial blood pressure, while it decreased HDL-C and increased LDL-C, total cholesterol and triglycerides in serum. Arsenic down-regulated eNOS and up-regulated iNOS protein expression and increased basal NO and 3-nitrotyrosine level. Arsenic increased aortic Nox-4 and p22Phox mRNA expression, Nox activity, ROS generation and lipid peroxidation. Further, arsenic decreased the activities of superoxide dismutase, catalase, and glutathione peroxidase and depleted aortic GSH content. Atorvastatin regularized blood pressure, improved lipid profile and attenuated arsenic-mediated redox alterations. The results demonstrate that atorvastatin has the potential to ameliorate arsenic-induced hypertension by improving lipid profile, aortic NO signaling and restoring vascular redox homeostasis. - Highlights: • Arsenic increased systolic, diastolic and mean arterial blood pressure and caused dyslipidemia. • Arsenic increased

  11. Interactions of mycorrhizal fungi with Pteris vittata (As hyperaccumulator) in As-contaminated soils

    International Nuclear Information System (INIS)

    Leung, H.M.; Ye, Z.H.; Wong, M.H.

    2006-01-01

    A greenhouse trial was conducted to investigate the role of arbuscular mycorrhizas (AM) in aiding arsenic (As) uptake and tolerance by Pteris vittata (As hyperaccumulator) and Cynodon dactylon (a multi-metal root accumulator). Plants inoculated with lived and killed native mycorrhizas isolated from an As mine site were grown in a sterile and slightly acidic soil. The infectious percentage of mycorrhizas (0 mg/kg As: 26.4%, 50 mg/kg As: 30.3%, 100 mg/kg As: 40.6%) and the average biomass of shoots in infected P. vittata increased (0 mg/kg As: 2.45 g/pot, 50 mg/kg As: 2.48 g/pot, 100 mg/kg As: 10.9 g/pot) according to the increase of As levels when compared to control. The indigenous mycorrhizas enhanced As accumulation (0 mg/kg As: 3.70 mg/kg, 50 mg/kg As: 58.3 mg/kg; 100 mg/kg As: 88.1 mg/kg) in the As mine populations of P. vittata and also sustained its growth by aiding P absorption. For C. dactylon, As was mainly accumulated in mycorrhizal roots and translocation to shoots was inhibited. - Indigenous mycorrhizal fungi play an important role in As tolerance

  12. Interactions of mycorrhizal fungi with Pteris vittata (As hyperaccumulator) in As-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Leung, H.M. [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong (China); Ye, Z.H. [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong (China); School of Life Sciences, Zhongshan University, Guangzhou 510275 (China); Wong, M.H. [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong (China)]. E-mail: mhwong@hkbu.edu.hk

    2006-01-15

    A greenhouse trial was conducted to investigate the role of arbuscular mycorrhizas (AM) in aiding arsenic (As) uptake and tolerance by Pteris vittata (As hyperaccumulator) and Cynodon dactylon (a multi-metal root accumulator). Plants inoculated with lived and killed native mycorrhizas isolated from an As mine site were grown in a sterile and slightly acidic soil. The infectious percentage of mycorrhizas (0 mg/kg As: 26.4%, 50 mg/kg As: 30.3%, 100 mg/kg As: 40.6%) and the average biomass of shoots in infected P. vittata increased (0 mg/kg As: 2.45 g/pot, 50 mg/kg As: 2.48 g/pot, 100 mg/kg As: 10.9 g/pot) according to the increase of As levels when compared to control. The indigenous mycorrhizas enhanced As accumulation (0 mg/kg As: 3.70 mg/kg, 50 mg/kg As: 58.3 mg/kg; 100 mg/kg As: 88.1 mg/kg) in the As mine populations of P. vittata and also sustained its growth by aiding P absorption. For C. dactylon, As was mainly accumulated in mycorrhizal roots and translocation to shoots was inhibited. - Indigenous mycorrhizal fungi play an important role in As tolerance.

  13. Mthfr gene ablation enhances susceptibility to arsenic prenatal toxicity

    International Nuclear Information System (INIS)

    Wlodarczyk, Bogdan J.; Zhu, Huiping; Finnell, Richard H.

    2014-01-01

    Background: In utero exposure to arsenic is known to adversely affect reproductive outcomes. Evidence of arsenic teratogenicity varies widely and depends on individual genotypic differences in sensitivity to As. In this study, we investigated the potential interaction between 5,10-methylenetetrahydrofolate reductase (Mthfr) genotype and arsenic embryotoxicity using the Mthfr knockout mouse model. Methods: Pregnant dams were treated with sodium arsenate, and reproductive outcomes including: implantation, resorption, congenital malformation and fetal birth weight were recorded at E18.5. Results: When the dams in Mthfr +/− × Mthfr +/− matings were treated with 7.2 mg/kg As, the resorption rate increased to 43.4%, from a background frequency of 7.2%. The As treatment also induced external malformations (40.9%) and significantly lowered the average fetal birth weight among fetuses, without any obvious toxic effect on the dam. When comparing the pregnancy outcomes resulting from different mating scenarios (Mthfr +/+ × Mthfr +/− , Mthfr +/− × Mthfr +/− and Mthfr −/− × Mthfr+/− ) and arsenic exposure; the resorption rate showed a linear relationship with the number of null alleles (0, 1 or 2) in the Mthfr dams. Fetuses from nullizygous dams had the highest rate of external malformations (43%) and lowest average birth weight. When comparing the outcomes of reciprocal matings (nullizygote × wild-type versus wild-type × nullizygote) after As treatment, the null dams showed significantly higher rates of resorptions and malformations, along with lower fetal birth weights. Conclusions: Maternal genotype contributes to the sensitivity of As embryotoxicity in the Mthfr mouse model. The fetal genotype, however, does not appear to affect the reproductive outcome after in utero As exposure. - Highlights: • An interaction between Mthfr genotype and arsenic embryotoxicity is presented. • Maternal Mthfr genotype contributes to the sensitivity of As

  14. Effect of Household Solid Waste on Initial Growth Performance of Acacia auriculiformis and Cedrela toona in Mycorrhiza Inoculated Soil

    Directory of Open Access Journals (Sweden)

    M.M. Abdullah-Al-Mamun

    2015-09-01

    Full Text Available Solid waste disposal and management became one of the major environmental concerns in Bangladesh. Realising the problem, the present study has been undertaken with a view to find a sound and effective way of bio-degradable solid waste management. The study was carried out in the nursery of Institute of Forestry and Environmental Sciences at University of Chittagong to determine the effects of solid waste and waste inoculated with mycorrhizal soil on initial growth performance of Acacia auriculiformis and Cedrela toona. Before planting the seedlings, decomposable waste and mycorrhiza inoculated decomposable waste were placed on the planting holes. Physical growth parameters of seedlings (shoot and root length, leaf and branch number, fresh and dry weight of shoot and root and nodulation status and the macro nutrients (N, P and K were recorded after six months of planting. The highest performance of physical parameters was recorded in the soil treated by mycorrhiza inoculated waste. Cedrela toona was represented by maximum nutrients uptake (N-2.60%, P-0.21% and K-2.34% respectively in the soil treated with mycorrhiza. In case of Acacia auriculiformis, N uptake was maximum (3.02% in control while K uptake was highest (1.27% in soil with waste and P (0.18% uptake was highest in the soil treated with mycorrhiza inoculated waste. Highest initial growth performance was revealed by seedlings treated with mycorrhiza inoculated waste. This study suggested to use mycorrhiza and waste for plantation purposes for hygienic disposal of solid waste and to reduce cost of cultivation.

  15. Mycorrhiza helper bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Deveau, Aurelie [French National Insitute for Agricultural Research (INRA); Labbe, Jessy [ORNL

    2016-10-01

    This chapter focuses on the Mycorrhiza Helper Bacteria (MHB), a generic name given to bacteria which stimulate the formation of mycorrhizal symbiosis. By extension, some bacterial strains that positively impact the functioning of mycorrhizal symbiosis are also called MHB. These bacteria have applicative interests, as they indirectly improve the health and growth of tree seedlings. MHB are not restricted to a specific type of ecosystem, but are rather generalist in the way that they associate with both herbaceous and woody mycorrhizal plants from boreal, temperate, arid and tropical ecosystems. However, understanding the molecular mechanisms and their specificities will help us to know more about the ecology of the MHB. The process of acquisition varies between fungal species; while ectomycorrhizal fungi most probably recurrently acquire them from the environment, the association between bacterial endosymbionts and Glomeromycota probably dates back to very ancient times, and has since been vertically transmitted.

  16. Enhanced protective activity of nano formulated andrographolide against arsenic induced liver damage.

    Science.gov (United States)

    Das, Sujata; Pradhan, Goutam Kumar; Das, Subhadip; Nath, Debjani; Das Saha, Krishna

    2015-12-05

    Chronic exposure to arsenic over a period of time induces toxicity, primarily in liver but gradually in all systems of the body. Andrographolide (AG), a major diterpene lactone of Andrographis paniculata, shows a wide array of physiological functions including hepatoprotection. Therapeutic applications of AG are however seriously constrained because of its insolubility, poor bioavailability, and short plasma half-life. Nanoparticulation of AG is a possible solution to these problems. In the present study we investigated the effectiveness of polylactide co-glycolide (PLGA) nanocapsulated andrographolide (NA) against arsenic induced liver damage in mice. NA of average diameter 65.8 nm and encapsulation efficiency of 64% were prepared. Sodium arsenite at a dose of 40 mg/L supplied via drinking water in mice significantly raised the serum level of liver function markers such as AST, ALT, and ALP, and caused arsenic deposition in liver and ROS generation, though it did not show any lethality up to 30 days of exposure. However, even liver toxicity was not observed when mice were given AG and NA orally at doses up to 100 mg/kg bwt and 20 mg/kg bwt respectively on alternate days for one month. Treatment of non-toxic doses of AG or NA on alternate days along with arsenic significantly decreased the arsenic induced elevation of the serum level of ALT, AST and ALP, and arsenic deposition in liver. AG and NA increased the level of hepatic antioxidant enzymes such as superoxide dismutase (SOD), and catalase (CAT), and the level of reduced glutathione (GSH). Also, the ROS level was lowered in mice exposed to arsenic but treated with AG or NA. Protective efficiency of NA is about five times more than that of AG. Administration of NA to arsenic-treated mice caused signs of improvement in liver tissue architecture. In conclusion, the results of this study suggest that NA could be beneficial against arsenic-induced liver toxicity. Copyright © 2015 Elsevier Ireland Ltd. All rights

  17. Arsenic Remediation by Synthetic and Natural Adsorbents

    Directory of Open Access Journals (Sweden)

    Muhammad Saqaf Jagirani

    2017-06-01

    Full Text Available The contagion of toxic metals in water is a serious environmental and health concern and threatening problem worldwide. Particularly arsenic contamination in ground water has became great dilemma in the earlier decades. With advent in research for arsenic remediation, standard of drinking water is improving and now reduced to few parts per million (ppm level of arsenic in drinking water sources. However, due to continuous enhancement in environmental pollution, remediation techniques are still needed to achieve the drinking water quality standard. Development of novel and economically feasible removal techniques or materials for selective separation of this toxic specie has been the main focus of research. Several arsenic removal techniques, including membrane separation, coagulation, precipitation, anion exchange have been developed. The aim of this article is to review briefly arsenic chemistry and previous and current available technologies that have been reported various low-cost adsorbents for arsenic removal.

  18. Evaluation of Two Mycorrhiza Species and Nitroxin on Yield and Yield Components of Garlic (Allium sativum L.) in an Ecological Agroecosystem

    OpenAIRE

    P Rezvani Moghaddam; M. B Amiri; A Norozian; H. R Ehyaee

    2016-01-01

    Introduction Maintenance of soil fertility is one of the most important issues affecting the sustainability of food production. The application of ecological inputs such as mycorrhiza and biofertilizers are one of those approaches which are needed to maintain soil fertility Biofetilizers include different types of free living organisms that convert unavailable nutrients to available forms and enhance root development and better seed germination. Plant growth promoting rhizobacteria (PGPR)...

  19. Cloning arbuscule-related genes from mycorrhizas

    DEFF Research Database (Denmark)

    Burleigh, Stephen

    2000-01-01

    Until recently little was known about the identity of the genes expressed in the arbuscules of mycorrhizas, due in part to problems associated with cloning genes from the tissues of an obligate symbiont. However, the combination of advanced molecular techniques, innovative use of the materials...... available and fortuitous cloning has resulted in the recent identification of a number of arbuscule-related genes. This article provides a brief summary of the genes involved in arbuscule development, function and regulation, and the techniques used to study them. Molecular techniques include differential...

  20. Response of free-living soil protozoa and microorganisms to elevated atmospheric CO2 and presence of mycorrhiza

    DEFF Research Database (Denmark)

    Rønn, R.; Gavito, M.; Larsen, J.

    2002-01-01

    with or without the presence of the arbuscular mycorrhizal (AM) fungus Glomus caledonium. It was hypothesised that (1) the populations of free-living soil protozoa would increase as a response to elevated CO2, (2) the effect of elevated CO2 on protozoa would be moderated by the presence of mycorrhiza and (3......) the presence of arbuscular mycorrhiza would affect soil protozoan numbers regardless of atmospheric CO2. After 3 weeks growth there was no difference in bacterial numbers (direct counts) in soil, but the number of free-living bacterial-feeding protozoa was significantly higher under elevated CO2...... elevated CO2 suggest increased bacterial production, whereas the lower populations in response to presence of mycorrhiza suggest a depressing effect on bacterial production by AM colonisation. (C) 2002 Elsevier Science Ltd. All rights reserved....

  1. Mthfr gene ablation enhances susceptibility to arsenic prenatal toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Wlodarczyk, Bogdan J., E-mail: bwlodarczyk@austin.utexas.edu; Zhu, Huiping; Finnell, Richard H.

    2014-02-15

    Background: In utero exposure to arsenic is known to adversely affect reproductive outcomes. Evidence of arsenic teratogenicity varies widely and depends on individual genotypic differences in sensitivity to As. In this study, we investigated the potential interaction between 5,10-methylenetetrahydrofolate reductase (Mthfr) genotype and arsenic embryotoxicity using the Mthfr knockout mouse model. Methods: Pregnant dams were treated with sodium arsenate, and reproductive outcomes including: implantation, resorption, congenital malformation and fetal birth weight were recorded at E18.5. Results: When the dams in Mthfr{sup +/−} × Mthfr{sup +/−} matings were treated with 7.2 mg/kg As, the resorption rate increased to 43.4%, from a background frequency of 7.2%. The As treatment also induced external malformations (40.9%) and significantly lowered the average fetal birth weight among fetuses, without any obvious toxic effect on the dam. When comparing the pregnancy outcomes resulting from different mating scenarios (Mthfr{sup +/+} × Mthfr{sup +/−}, Mthfr{sup +/−} × Mthfr{sup +/−} and Mthfr{sup −/−} × {sup Mthfr+/−}) and arsenic exposure; the resorption rate showed a linear relationship with the number of null alleles (0, 1 or 2) in the Mthfr dams. Fetuses from nullizygous dams had the highest rate of external malformations (43%) and lowest average birth weight. When comparing the outcomes of reciprocal matings (nullizygote × wild-type versus wild-type × nullizygote) after As treatment, the null dams showed significantly higher rates of resorptions and malformations, along with lower fetal birth weights. Conclusions: Maternal genotype contributes to the sensitivity of As embryotoxicity in the Mthfr mouse model. The fetal genotype, however, does not appear to affect the reproductive outcome after in utero As exposure. - Highlights: • An interaction between Mthfr genotype and arsenic embryotoxicity is presented. • Maternal Mthfr genotype

  2. Fractionation of Nitrogen Isotopes by Plants with Different Types of Mycorrhiza in Mountain Tundra Ecosystems

    Science.gov (United States)

    Buzin, Igor; Makarov, Mikhail; Maslov, Mikhail; Tiunov, Alexei

    2017-04-01

    We studied nitrogen concentration and nitrogen isotope composition in plants from four mountain tundra ecosystems in the Khibiny Mountains. The ecosystems consisted of a toposequence beginning with the shrub-lichen heath (SLH) on the ridge and upper slope, followed by the Betula nana dominated shrub heath (SH) on the middle slope, the cereal meadow (CM) on the lower slope and the sedge meadow (SM) at the bottom of the slope. The inorganic nitrogen concentration of the soils from the studied ecosystems were significantly different; the SLH soil was found to contain the minimum concentration of N-NH4+ and N-NO3- , while in the soils of the meadow ecosystems these concentrations were much higher. The concentration of nitrogen in leaves of the dominant plant species in all of the ecosystems is directly connected with the concentration of inorganic nitrogen in the soils, regardless of the plant's mycorrhizal symbiosis type. However, such a correlation is not apparent in the case of plant roots, especially for plant roots with ectomycorrhiza and ericoid mycorrhiza. The majority of plant species with these types of mycorrhiza in the SH and particularly in the CM were enriched in 15N in comparison with the SLH (such plants were not found within the SM). This could be due to several reasons: 1) the decreasing role of mycorrhiza in nitrogen consumption and therefore in the fractionation of isotopes in the relatively-N-enriched ecosystems; 2) the use of relatively-15N-enriched forms of nitrogen for plant nutrition in meadow ecosystems. This heavier nitrogen isotope composition in plant roots with ectomycorrhiza and ericoid mycorrhiza in ecosystems with available nitrogen enriched soils doesn't correspond to the classical idea of mycorrhiza decreasing participation in nitrogen plant nutrition. The analysis of the isotope composition of separate labile forms of nitrogen makes it possible to explain the phenomenon. Not all arbuscular mycorrhizal species within the sedge meadow

  3. 134Cs in heather seed plants grown with and without mycorrhiza

    International Nuclear Information System (INIS)

    Strandberg, M.; Johansson, M.

    1988-01-01

    Experiments were carried out to determine differences between mycorrhized and non-mycorrhized seed plants of heather, Calluna vulgaris(L)Hull, as regards the uptake of 134 Cs. In most treatments heather with mycorrhiza had a significantly higher transfer of 134 Cs to the shoots than heather without mycorrhiza. As an average the concentration of 134 Cs was 18% higher in the mycorrhized plants than in the non-mycorrhized. Application of 10 kg K/ha reduced the concentration of 134 Cs in shoots of heather by 49% as an average. Because of improved growth in the potassium fertilized pots the reduction viewed on the basis of the area was only 33%. Nitrogen application does not significantly influence the concentration of 134 Cs in shoots of heather regardless of mycorrhizal status. (Copyright (c) 1988 Elsevier Science B.V., Amsterdam. All rights reserved.)

  4. Effects of metal lead on growth and mycorrhizae of an invasive plant species (Solidago canadensis L.).

    Science.gov (United States)

    Yang, Ruyi; Yu, Guodong; Tang, Jianjun; Chen, Xin

    2008-01-01

    It is less known whether and how soil metal lead (Pb) impacts the invasion of exotic plants. A greenhouse experiment was conducted to estimate the effects of lead on the growth and mycorrhizae of an invasive species (Solidago canadensis L.) in a microcosm system. Each microcosm unit was separated into HOST and TEST compartments by a replaceable mesh screen that allowed arbuscular mycorrhizal (AM) fungal hyphae rather than plant roots to grow into the TEST compartments. Three Pb levels (control, 300, and 600 mg/kg soil) were used in this study to simulate ambient soil and two pollution sites where S. canadensis grows. Mycorrhizal inoculum comprised five indigenous arbuscular mycorrhizal fungal species (Glomus mosseae, Glomus versiform, Glomus diaphanum, Glomus geosporum, and Glomus etunicatum). The 15N isotope tracer was used to quantify the mycorrhizally mediated nitrogen acquisition of plants. The results showed that S. canadensis was highly dependent on mycorrhizae. The Pb additions significantly decreased biomass and arbuscular mycorrhizal colonization (root length colonized, RLC%) but did not affect spore numbers, N (including total N and 15N) and P uptake. The facilitating efficiency of mycorrhizae on nutrient acquisition was promoted by Pb treatments. The Pb was mostly sequestered in belowground of plant (root and rhizome). The results suggest that the high efficiency of mycorrhizae on nutrient uptake might give S. canadensis a great advantage over native species in Pb polluted soils.

  5. Effects of Mycorrhiza on the Growth and Productivity of Faidherbia ...

    African Journals Online (AJOL)

    The effects of mycorrhiza on growth and growth components of Faidherbia albida (Del.) A. Chev. was investigated in the semi arid environment of Sokoto State, Nigeria. A complete randomized block design with five replications and factorial combination of three watering regimes (daily for unstressed plant, twice weekly for ...

  6. Correlation of Breastmilk Arsenic With Maternal, Infant Urinary Arsenic and Drinking Water Arsenic in an Arsenic Affected Area of Bangladesh

    Science.gov (United States)

    Alauddin, M.; Islam, M. R.; Milton, A. H.; Alauddin, S. T.; Mouly, T.; Behri, E.; Ayesha, A.; Akter, S.; Islam, M. M.

    2016-12-01

    About 97% of population in Bangladesh depend on groundwater as the principle source of drinking water and this water is highly contaminated with inorganic arsenic. Consumption of arsenic contaminated drinking water by pregnant women raises the prospect of early life exposure to inorganic arsenic for newborn which may be lead to adverse health effect in later life. This work was carried out in parts of Gopalganj district in Bangladesh, a region affected by arsenic contamination in groundwater. The objective of the work was to assess potential early life exposure to arsenic for infants through breastfeeding by mothers who were drinking water with arsenic levels ranging from 100 to 300 µg/l. A cohort of 30 mother-baby pairs were selected for the current study. Breastmilk samples from mothers, urine samples from each pair of subjects at 1, 6 and 9 month age of infant were collected and total arsenic were determined in these samples. In addition speciation of urinary arsenic and metabolites were carried out in 12 mother-baby pairs. Median level for breastmilk arsenic were 0.50 µg/l. Urinary arsenic of infants did not correlate with breastmilk arsenic with progressing age of infants. Maternal and infant urinary total arsenic at 1 month age of infant showed some positive correlation (r = 0.39). In infant urine major metabolite were dimethyl arsenic acid (DMA) (approximately 70%) indicating good methylating capacity for infants at 1 and 6 months of age. In conclusion, infants were not exposed to arsenic through breastfeeding even though mothers were exposed to significant levels of arsenic through drinking water.

  7. Survey the Effect of Mycorrhiza and Azospirillum of Wheat Cultivars Resistance in Yellow Rust

    Directory of Open Access Journals (Sweden)

    M. Jiriaie

    2017-01-01

    -levels (non-inoculated seeds and inoculated seed and wheat cultivars in three levels, Chamran (bread wheat, Dena and Behrang (durum wheat varieties. In this experiment evaluated, to yellow rust disease, the intensity of infection, the average coefficient of infection, type of infection and area under disease progress curve (AUDPC. Infection type and disease severity were also recorded at flag leaf stage using modified Cobb’s scale. First symptoms of yellow rust were observed in middle January of 2013. Analysis of variance was performed using PROC ANOVA of SAS (version 9.1.3, 2004The comparison of the means was done by Duncan test at a probability level of 5 percent. Results and Discussion: Survey on the resistance to yellow rust in wheat cultivars treated with Mycorrhiza and Azospirillum showed that seed inoculation with Azospirillum traits reduced between 10 percent to 13 percent and the use strains of Mycorrhiza fungi intensity of infection 45-51 percent, the average coefficient of infection and AUDPC 74-85 percent respectively for G. intraradices and G. mosseae strains have been reduced compared with control and Chamran cultivar between 40-70 percent showed more Sensitivity to disease from durum varieties. Generally, the lowest of infection intensity (18.33 was obtained from inoculation of C.V Dena seeds with Azospirillum and G. mosseae strain. According to the result, we found yellow rust in all experiment field also the incidence varied between 10-70 percent. Therefore, it is concluded that, given the climatic conditions favorable to the spread of yellow rust, the incidence of yellow rust in the region that have a high degree of pathogenicity. In general the results of this test, mycorrhiza application has a significant role in enhancing wheat resistance to yellow rust. The seed inoculation with Azospirillum although did not have significant role in disease control, but increased at an acceptable level resistance to wheat rust. But the important point was the combined

  8. Gibberellin-Abscisic Acid Balances during Arbuscular Mycorrhiza Formation in Tomato

    Czech Academy of Sciences Publication Activity Database

    Martin-Rodriguez, J.A.; Huertas, R.; Ho-Plagaro, T.; Ocampo, J.A.; Turečková, Veronika; Tarkowská, Danuše; Ludwig-Mueller, J.; Garcia-Garrido, J.M.

    2016-01-01

    Roč. 7, AUG 23 (2016), s. 1273 ISSN 1664-462X R&D Projects: GA ČR GA14-34792S; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : arbuscular mycorrhiza * plant hormones * gibberellins Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.298, year: 2016

  9. Arsenic geochemistry of groundwater in Southeast Asia.

    Science.gov (United States)

    Kim, Kyoung-Woong; Chanpiwat, Penradee; Hanh, Hoang Thi; Phan, Kongkea; Sthiannopkao, Suthipong

    2011-12-01

    The occurrence of high concentrations of arsenic in the groundwater of the Southeast Asia region has received much attention in the past decade. This study presents an overview of the arsenic contamination problems in Vietnam, Cambodia, Lao People's Democratic Republic and Thailand. Most groundwater used as a source of drinking water in rural areas has been found to be contaminated with arsenic exceeding the WHO drinking water guideline of 10 μg·L(-1). With the exception of Thailand, groundwater was found to be contaminated with naturally occurring arsenic in the region. Interestingly, high arsenic concentrations (> 10 μg·L(-1)) were generally found in the floodplain areas located along the Mekong River. The source of elevated arsenic concentrations in groundwater is thought to be the release of arsenic from river sediments under highly reducing conditions. In Thailand, arsenic has never been found naturally in groundwater, but originates from tin mining activities. More than 10 million residents in Southeast Asia are estimated to be at risk from consuming arsenic-contaminated groundwater. In Southeast Asia, groundwater has been found to be a significant source of daily inorganic arsenic intake in humans. A positive correlation between groundwater arsenic concentration and arsenic concentration in human hair has been observed in Cambodia and Vietnam. A substantial knowledge gap exists between the epidemiology of arsenicosis and its impact on human health. More collaborative studies particularly on the scope of public health and its epidemiology are needed to conduct to fulfill the knowledge gaps of As as well as to enhance the operational responses to As issue in Southeast Asian countries.

  10. Binational Arsenic Exposure Survey: Methodology and Estimated Arsenic Intake from Drinking Water and Urinary Arsenic Concentrations

    Directory of Open Access Journals (Sweden)

    Robin B. Harris

    2012-03-01

    Full Text Available The Binational Arsenic Exposure Survey (BAsES was designed to evaluate probable arsenic exposures in selected areas of southern Arizona and northern Mexico, two regions with known elevated levels of arsenic in groundwater reserves. This paper describes the methodology of BAsES and the relationship between estimated arsenic intake from beverages and arsenic output in urine. Households from eight communities were selected for their varying groundwater arsenic concentrations in Arizona, USA and Sonora, Mexico. Adults responded to questionnaires and provided dietary information. A first morning urine void and water from all household drinking sources were collected. Associations between urinary arsenic concentration (total, organic, inorganic and estimated level of arsenic consumed from water and other beverages were evaluated through crude associations and by random effects models. Median estimated total arsenic intake from beverages among participants from Arizona communities ranged from 1.7 to 14.1 µg/day compared to 0.6 to 3.4 µg/day among those from Mexico communities. In contrast, median urinary inorganic arsenic concentrations were greatest among participants from Hermosillo, Mexico (6.2 µg/L whereas a high of 2.0 µg/L was found among participants from Ajo, Arizona. Estimated arsenic intake from drinking water was associated with urinary total arsenic concentration (p < 0.001, urinary inorganic arsenic concentration (p < 0.001, and urinary sum of species (p < 0.001. Urinary arsenic concentrations increased between 7% and 12% for each one percent increase in arsenic consumed from drinking water. Variability in arsenic intake from beverages and urinary arsenic output yielded counter intuitive results. Estimated intake of arsenic from all beverages was greatest among Arizonans yet participants in Mexico had higher urinary total and inorganic arsenic concentrations. Other contributors to urinary arsenic concentrations should be evaluated.

  11. Antioxidative responses to arsenic in the arsenic-hyperaccumulator Chinese brake fern (Pteris vittata L.)

    International Nuclear Information System (INIS)

    Cao Xinde; Ma, Lena Q.; Tu Cong

    2004-01-01

    This study measured antioxidative responses of Chinese brake fern (Pteris vittata L.) upon exposure to arsenic (As) of different concentrations. Chinese brake fern was grown in an artificially-contaminated soil containing 0 to 200 mg As kg -1 (Na 2 HAsO 4 ) for 12 weeks in a greenhouse. Soil As concentrations at ≤20 mg kg -1 enhanced plant growth, with 12-71% biomass increase compared to the control. Such beneficial effects were not observed at >20 mg As kg -1 . Plant As concentrations increased with soil As concentrations, with more As being accumulated in the fronds (aboveground biomass) than in the roots and with maximum frond As concentration being 4675 mg kg -1 . Arsenic uptake by Chinese brake enhanced uptake of nutrient elements K, P, Fe, Mn, and Zn except Ca and Mg, whose concentrations mostly decreased. The contents of non-enzymatic antioxidants (glutathione, acid-soluble thiol) followed similar trends as plant As concentrations, increasing with soil As concentrations, with greater contents in the fronds than in the roots especially when exposed to high As concentrations (>50 mg kg -1 ). The activities of enzymatic antioxidants (superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase) in Chinese brake followed the same trends as plant biomass, increasing with soil As up to 20 mg kg -1 and then decreased. The results indicated though both enzymatic and non-enzymatic antioxidants played significant roles in As detoxification and hyperaccumulation in Chinese brake, the former is more important at low As exposure (≤20 mg kg -1 ), whereas the latter is more critical at high As exposure (50-200 mg kg -1 ). - At low levels of arsenic exposure, enzymatic antioxidants are important for arsenic detoxification and accumulation in Chinese brake fern, while non-enzymatic antioxidants were more important at high arsenic exposure

  12. Interactions of arsenic and phenanthrene on their uptake and antioxidative response in Pteris vittata L

    International Nuclear Information System (INIS)

    Sun Lu; Yan Xiulan; Liao Xiaoyong; Wen Yi; Chong Zhongyi; Liang Tao

    2011-01-01

    The interactions of arsenic and phenanthrene on plant uptake and antioxidative response of Pteris vitatta L. were studied hydroponically. The combination of arsenic and phenanthrene decreased arsenic contents in fronds by 30-51%, whereas increased arsenic concentrations 1.2-1.6 times in roots, demonstrating the suppression of arsenic translocation compared to the corresponding treatment without phenanthrene. Under the co-exposure, As(III) concentrations in fronds deceased by 12-73%, and at higher arsenic exposure level (≥10 mg/L), As(V) in fronds and As(III) in roots increased compared to the single arsenic treatment. Arsenic exposure elevated phenanthrene concentrations in root by 39-164%. The co-existence of arsenic and phenanthrene had little impact on plant arsenic accumulation, although synergistic effect on antioxidants was observed, suggesting the special physiological process of P. vitatta in the co-exposure and application potential of P. vitatta in phytoremediation of arsenic and PAHs co-contamination. - Highlights: → Pteris vitatta L. show tolerance to the arsenic and phenanthrene co-exposure. → P. vitatta efficiently accumulate arsenic and simultaneously enhance phenanthrene dissipation. → Phenanthrene suppresses arsenic translocation from roots to fronds. → Phenanthrene causes As(III) elevation in roots while reduction in fronds. → Synergistic effect potentiates the toxicity and antioxidants in plant. - Pteris vitatta L. not only efficiently accumulate arsenic but also enhance phenanthrene dissipation under the arsenic and phenanthrene co-exposure.

  13. Interactions of arsenic and phenanthrene on their uptake and antioxidative response in Pteris vittata L

    Energy Technology Data Exchange (ETDEWEB)

    Sun Lu [Beijing Key Lab of Industrial Land Contamination and Remediation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100049 (China); Yan Xiulan [Beijing Key Lab of Industrial Land Contamination and Remediation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101 (China); Liao Xiaoyong, E-mail: liaoxy@igsnrr.ac.cn [Beijing Key Lab of Industrial Land Contamination and Remediation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101 (China); Wen Yi; Chong Zhongyi; Liang Tao [Beijing Key Lab of Industrial Land Contamination and Remediation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101 (China)

    2011-12-15

    The interactions of arsenic and phenanthrene on plant uptake and antioxidative response of Pteris vitatta L. were studied hydroponically. The combination of arsenic and phenanthrene decreased arsenic contents in fronds by 30-51%, whereas increased arsenic concentrations 1.2-1.6 times in roots, demonstrating the suppression of arsenic translocation compared to the corresponding treatment without phenanthrene. Under the co-exposure, As(III) concentrations in fronds deceased by 12-73%, and at higher arsenic exposure level ({>=}10 mg/L), As(V) in fronds and As(III) in roots increased compared to the single arsenic treatment. Arsenic exposure elevated phenanthrene concentrations in root by 39-164%. The co-existence of arsenic and phenanthrene had little impact on plant arsenic accumulation, although synergistic effect on antioxidants was observed, suggesting the special physiological process of P. vitatta in the co-exposure and application potential of P. vitatta in phytoremediation of arsenic and PAHs co-contamination. - Highlights: > Pteris vitatta L. show tolerance to the arsenic and phenanthrene co-exposure. > P. vitatta efficiently accumulate arsenic and simultaneously enhance phenanthrene dissipation. > Phenanthrene suppresses arsenic translocation from roots to fronds. > Phenanthrene causes As(III) elevation in roots while reduction in fronds. > Synergistic effect potentiates the toxicity and antioxidants in plant. - Pteris vitatta L. not only efficiently accumulate arsenic but also enhance phenanthrene dissipation under the arsenic and phenanthrene co-exposure.

  14. Influence of arbuscular mycorrhizae on photosynthesis and water status of maize plants under salt stress.

    Science.gov (United States)

    Sheng, Min; Tang, Ming; Chen, Hui; Yang, Baowei; Zhang, Fengfeng; Huang, Yanhui

    2008-09-01

    The influence of arbuscular mycorrhizal (AM) fungus Glomus mosseae on characteristics of the growth, water status, chlorophyll concentration, gas exchange, and chlorophyll fluorescence of maize plants under salt stress was studied in the greenhouse. Maize plants were grown in sand and soil mixture with five NaCl levels (0, 0.5, 1.0, 1.5, and 2.0 g/kg dry substrate) for 55 days, following 15 days of non-saline pretreatment. Under salt stress, mycorrhizal maize plants had higher dry weight of shoot and root, higher relative chlorophyll content, better water status (decreased water saturation deficit, increased water use efficiency, and relative water content), higher gas exchange capacity (increased photosynthetic rate, stomatal conductance and transpiration rate, and decreased intercellular CO(2) concentration), higher non-photochemistry efficiency [increased non-photochemical quenching values (NPQ)], and higher photochemistry efficiency [increased the maximum quantum yield in the dark-adapted state (Fv/Fm), the maximum quantum yield in the light-adapted sate (Fv'/Fm'), the actual quantum yield in the light-adapted steady state (phiPSII) and the photochemical quenching values (qP)], compared with non-mycorrhizal maize plants. In addition, AM symbiosis could trigger the regulation of the energy biturcation between photochemical and non-photochemical events reflected in the deexcitation rate constants (kN, kN', kP, and kP'). All the results show that G. mosseae alleviates the deleterious effect of salt stress on plant growth, through improving plant water status, chlorophyll concentration, and photosynthetic capacity, while the influence of AM symbiosis on photosynthetic capacity of maize plants can be indirectly affected by soil salinity and mycorrhizae-mediated enhancement of water status, but not by the mycorrhizae-mediated enhancement of chlorophyll concentration and plant biomass.

  15. The effects of arsenic or the combination of arsenic and radiation exposure is enhanced through the overexpression of the GSTO family member p28

    International Nuclear Information System (INIS)

    Giri, U.; Story, M.D.; Terry, N.H.A.; Giri, D.K.; Calkins, P.R.

    2003-01-01

    Full text: p28 is a member of the GST omega superfamily and has dehydroascorbate reductase, GST, and glutaredoxin activities. Furthermore, p28 is the rate-limiting enzyme in the bio-transformation of arsenic. The monomethyl arsenous reducatase activity of p28 produces dimethylarseniate, the most toxic form of arsenic. We investigated how p28 modulated arsenic cellular sensitivity in two mammalian models: 1) in LY-ar and LY-as cells where p28 is over-expressed and not expressed, respectively; and 2) in stably transfected A549 cells where p28 is over-expressed via a CMV promoter. The LY-ar mouse lymphoma cell line is radio and chemo-resistant and apoptosis refractory, whereas the parental cell line, LY-as, is radiosensitive and apoptotically permissive. In addition, we studied the effect of arsenic as a radiosensitizer in both cell systems. In LY-ar cells arsenic induced a dose- and time- dependent increase in apoptosis, which is comparable to that seen in LY-as cells. Arsenic plus 2.5Gy radiation induced apoptosis in LY-ar cells, which was more than additive. Survival in LY-ar cells was reduced to that of LY-as cells as well as p28 overexpression induced G2/M arrest in A549 cells and the combination of radiation with arsenic decreased the clonogenic survival of both the A549 and A549-p28 cells but the effect is more pronounced in the A549-P28 cell line. A549 and A549-p28 cells did not show a differential response to Taxol, which induces G2/M arrest and cell death via an inhibition of tubulin depolarization. Arsenic modulated the level of reduced GSH in both cell systems in a dose- and time- dependent manner, which correlated with survival outcome. This study illustrated that arsenic acts as a radiosensitizer and p28 augmented the potential of arsenic in inducing apoptosis, G2/M arrest, and radiosensitization. Further studies are underway to examine the bio-chemical pathways involved in arsenic-mediated cell death and the role of p28 therein

  16. Early phosphorus nutrition, mycorrhizae development, dry matter partitioning and yield of maize

    DEFF Research Database (Denmark)

    Gavito, M.E.; Miller, M.H.

    1998-01-01

    to a mycorrhizal mycelium network (no-tillage treatments). Maize yield and harvest index were lower after cropping With canola. The yield for conventional tillage was higher than that for no-tillage but the harvest index was lower. The hypothesis was supported at early stages of maize growth by the effect...... was used with previous crop (Zea mays L.-maize and Brassica napus L.-canola), tillage practices (no-tillage or conventional tillage) and P fertilization (5 levels) as factors chosen to modify mycorrhizae development at early developmental stages of maize. Previous cropping with canola resulted in decreased......We conducted a field experiment to test the hypothesis that improved phosphorus nutrition occurs in maize plants with rapid arbuscular (AM) mycorrhizae development at early developmental stages and that this also is reflected in dry matter allocation and final yield. A split-split plot design...

  17. Sorption of Arsenic from Desalination Concentrate onto Drinking Water Treatment Solids: Operating Conditions and Kinetics

    Directory of Open Access Journals (Sweden)

    Xuesong Xu

    2018-01-01

    Full Text Available Selective removal of arsenic from aqueous solutions with high salinity is required for safe disposal of the concentrate and protection of the environment. The use of drinking water treatment solids (DWTS to remove arsenic from reverse osmosis (RO concentrate was studied by batch sorption experiments. The impacts of solution chemistry, contact time, sorbent dosage, and arsenic concentration on sorption were investigated, and arsenic sorption kinetics and isotherms were modeled. The results indicated that DWTS were effective in removing arsenic from RO concentrate. The arsenic sorption process followed a pseudo-second-order kinetic model. Multilayer adsorption was simulated by Freundlich equation. The maximum sorption capacities were calculated to be 170 mg arsenic per gram of DWTS. Arsenic sorption was enhanced by surface precipitation onto the DWTS due to the high amount of calcium in the RO concentrate and the formation of ternary complexes between arsenic and natural organic matter (NOM bound by the polyvalent cations in DWTS. The interactions between arsenic and NOM in the solid phase and aqueous phase exhibited two-sided effects on arsenic sorption onto DWTS. NOM in aqueous solution hindered the arsenic sorption onto DWTS, while the high organic matter content in solid DWTS phase enhanced arsenic sorption.

  18. Effect of simultaneous application of mycorrhiza with compost, vermicompost and sulfural geranole on some quantitative and qualitative characteristics of sesame (Sesamum indicum L. in a low input cropping system

    Directory of Open Access Journals (Sweden)

    P rezvani moghaddam

    2016-03-01

    Full Text Available Introduction In recent years, by increasing human knowledge and using different technology on food production, human concerns have increased on safety of food products especially medicinal crops. In order to achieve healthy food production, application of ecological inputs such as organic and biological fertilizers are inevitable. Organic fertilizers are fertilizer compounds that contain one or more kinds of organic matter. They can improve the soil ability to hold water and nutrients. They create a beneficial environment for earthworms and microbial organisms that break the soil down into rich, fine humus (Motta & Magggiore, 2013. Compost is organic matter that has been decomposed and recycled as a fertilizer and soil amendment. Compost can greatly enhance the physical structure of soil. The addition of compost may provide greater drought resistance and more efficient water utilization. Vermicompost is the final product of composting organic material using different types of worms, such as red wigglers or earthworms, to create a homogenized blend of decomposed vegetable and food waste, bedding materials and manure. Vermicompost helps store nutrients and keeps them safe from leaching and irrigation, functioning to balance hormones within plant physiology, and adding beneficial biology to soil (Raja Sekar & Karmegan, 2010. Mycorrhiza arbuscular fungi are other coexist microorganisms that improves soil fertility, nutrients cycling and agroecosystem health. Mycorrhizal fungi are the most abundant organisms in agricultural soils. Many researchers have pointed to the positive roles of mycorrhizal fungi on plants growth characteristics. Despite of many researches on the effect of organic and biological fertilizers on different crops, information on the effects of these fertilizers for many medicinal plants is scarce, therefore, in this study the effect of simultaneous application of mycorrhiza with compost, vermicompost and sulfural geranole on some

  19. Blockade and enhancement of glutamate receptor responses in Xenopus oocytes by methylated arsenicals

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, Katharina; Gruner, Janina; Madeja, Michael; Musshoff, Ulrich [Universitaetsklinikum Muenster, Institut fuer Physiologie I, Muenster (Germany); Hartmann, Louise M.; Hirner, Alfred V. [Universitaet Duisburg-Essen, Institut fuer Umweltanalytik, Essen (Germany); Binding, Norbert [Universitaetsklinikum Muenster, Institut fuer Arbeitsmedizin, Muenster (Germany)

    2006-08-15

    Pentavalent and trivalent organoarsenic compounds belong to the major metabolites of inorganic arsenicals detected in humans. Recently, the question was raised whether the organic arsenicals represent metabolites of a detoxification process or methylated species with deleterious biological effects. In this study, the effects of trivalent arsenite (AsO{sub 3} {sup 3-}; iA{sup III}), the pentavalent organoarsenic compounds monomethylarsonic acid (CH{sub 3}AsO(OH){sub 2}; MMA{sup V}) and dimethylarsinic acid ((CH{sub 3}){sub 2}AsO(OH); DMA{sup V}) and the trivalent compounds monomethylarsonous acid (CH{sub 3}As(OH){sub 2}, MMA{sup III}) and dimethylarsinous acid ((CH{sub 3}){sub 2}As(OH); DMA{sup III}) were tested on glutamate receptors and on voltage-operated potassium and sodium channels heterologously expressed in Xenopus oocytes. Membrane currents of ion channels were measured by conventional two-electrode voltage-clamp techniques. The effects of arsenite were tested in concentrations of 1-1,000 {mu}mol/l and the organic arsenical compounds were tested in concentrations of 0.1-100 {mu}mol/l. We found no significant effects on voltage-operated ion channels; however, the arsenicals exert different effects on glutamate receptors. While MMA{sup V} and MMA{sup III} significantly enhanced ion currents through N-methyl-d-aspartate (NMDA) receptor ion channels with threshold concentrations <10 {mu}mol/l, DMA{sup V} and DMA{sup III} significantly reduced NMDA-receptor mediated responses with threshold concentrations <0.1 {mu}mol/l; iA{sup III} had no effects on glutamate receptors of the NMDA type. MMA{sup III} and DMA{sup V} significantly reduced ion currents through {alpha}-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-receptor ion channels with threshold concentrations <10 {mu}mol/l (MMA{sup III}) and <1 {mu}mol/l (DMA{sup V}). MMA{sup V} and iA{sup III} had no significant effects on glutamate receptors of the AMPA type. The effects of MMA{sup V}, MMA

  20. Changes in mycorrhiza development in maize induced by crop management practices

    DEFF Research Database (Denmark)

    Gavito, M.E.; Miller, M.H.

    1998-01-01

    (Zea mays L.) or with the original plant species in the field site, bromegrass (Bromus inermis Leys.) and alfalfa (Medicago sativa L.). The delay in mycorrhiza development after cropping with canola was also observed in samples taken from the field and in a bioassay, both conducted at the beginning...

  1. Atractiellomycetes belonging to the ‘rust’ lineage (Pucciniomycotina) form mycorrhizae with terrestrial and epiphytic neotropical orchids

    Science.gov (United States)

    Kottke, Ingrid; Suárez, Juan Pablo; Herrera, Paulo; Cruz, Dario; Bauer, Robert; Haug, Ingeborg; Garnica, Sigisfredo

    2010-01-01

    Distinctive groups of fungi are involved in the diverse mycorrhizal associations of land plants. All previously known mycorrhiza-forming Basidiomycota associated with trees, ericads, liverworts or orchids are hosted in Agaricomycetes, Agaricomycotina. Here we demonstrate for the first time that Atractiellomycetes, members of the ‘rust’ lineage (Pucciniomycotina), are mycobionts of orchids. The mycobionts of 103 terrestrial and epiphytic orchid individuals, sampled in the tropical mountain rainforest of Southern Ecuador, were identified by sequencing the whole ITS1-5.8S-ITS2 region and part of 28S rDNA. Mycorrhizae of 13 orchid individuals were investigated by transmission electron microscopy. Simple septal pores and symplechosomes in the hyphal coils of mycorrhizae from four orchid individuals indicated members of Atractiellomycetes. Molecular phylogeny of sequences from mycobionts of 32 orchid individuals out of 103 samples confirmed Atractiellomycetes and the placement in Pucciniomycotina, previously known to comprise only parasitic and saprophytic fungi. Thus, our finding reveals these fungi, frequently associated to neotropical orchids, as the most basal living basidiomycetes involved in mycorrhizal associations of land plants. PMID:20007181

  2. The Arsenic Resistance-Associated Listeria Genomic Island LGI2 Exhibits Sequence and Integration Site Diversity and a Propensity for Three Listeria monocytogenes Clones with Enhanced Virulence.

    Science.gov (United States)

    Lee, Sangmi; Ward, Todd J; Jima, Dereje D; Parsons, Cameron; Kathariou, Sophia

    2017-11-01

    In the foodborne pathogen Listeria monocytogenes , arsenic resistance is encountered primarily in serotype 4b clones considered to have enhanced virulence and is associated with an arsenic resistance gene cluster within a 35-kb chromosomal region, Listeria genomic island 2 (LGI2). LGI2 was first identified in strain Scott A and includes genes putatively involved in arsenic and cadmium resistance, DNA integration, conjugation, and pathogenicity. However, the genomic localization and sequence content of LGI2 remain poorly characterized. Here we investigated 85 arsenic-resistant L. monocytogenes strains, mostly of serotype 4b. All but one of the 70 serotype 4b strains belonged to clonal complex 1 (CC1), CC2, and CC4, three major clones associated with enhanced virulence. PCR analysis suggested that 53 strains (62.4%) harbored an island highly similar to LGI2 of Scott A, frequently (42/53) in the same location as Scott A ( LMOf2365_2257 homolog). Random-primed PCR and whole-genome sequencing revealed seven novel insertion sites, mostly internal to chromosomal coding sequences, among strains harboring LGI2 outside the LMOf2365_2257 homolog. Interestingly, many CC1 strains harbored a noticeably diversified LGI2 (LGI2-1) in a unique location ( LMOf2365_0902 homolog) and with a novel additional gene. With few exceptions, the tested LGI2 genes were not detected in arsenic-resistant strains of serogroup 1/2, which instead often harbored a Tn 554 -associated arsenic resistance determinant not encountered in serotype 4b. These findings indicate that in L. monocytogenes , LGI2 has a propensity for certain serotype 4b clones, exhibits content diversity, and is highly promiscuous, suggesting an ability to mobilize various accessory genes into diverse chromosomal loci. IMPORTANCE Listeria monocytogenes is widely distributed in the environment and causes listeriosis, a foodborne disease with high mortality and morbidity. Arsenic and other heavy metals can powerfully shape the

  3. Transplacental arsenic carcinogenesis in mice

    International Nuclear Information System (INIS)

    Waalkes, Michael P.; Liu, Jie; Diwan, Bhalchandra A.

    2007-01-01

    Our work has focused on the carcinogenic effects of in utero arsenic exposure in mice. Our data show that a short period of maternal exposure to inorganic arsenic in the drinking water is an effective, multi-tissue carcinogen in the adult offspring. These studies have been reproduced in three temporally separate studies using two different mouse strains. In these studies pregnant mice were treated with drinking water containing sodium arsenite at up to 85 ppm arsenic from days 8 to 18 of gestation, and the offspring were observed for up to 2 years. The doses used in all these studies were well tolerated by both the dam and offspring. In C3H mice, two separate studies show male offspring exposed to arsenic in utero developed liver carcinoma and adrenal cortical adenoma in a dose-related fashion during adulthood. Prenatally exposed female C3H offspring show dose-related increases in ovarian tumors and lung carcinoma and in proliferative lesions (tumors plus preneoplastic hyperplasia) of the uterus and oviduct. In addition, prenatal arsenic plus postnatal exposure to the tumor promoter, 12-O-tetradecanoyl phorbol-13-acetate (TPA) in C3H mice produces excess lung tumors in both sexes and liver tumors in females. Male CD1 mice treated with arsenic in utero develop tumors of the liver and adrenal and renal hyperplasia while females develop tumors of urogenital system, ovary, uterus and adrenal and hyperplasia of the oviduct. Additional postnatal treatment with diethylstilbestrol or tamoxifen after prenatal arsenic in CD1 mice induces urinary bladder transitional cell proliferative lesions, including carcinoma and papilloma, and enhances the carcinogenic response in the liver of both sexes. Overall this model has provided convincing evidence that arsenic is a transplacental carcinogen in mice with the ability to target tissues of potential human relevance, such as the urinary bladder, lung and liver. Transplacental carcinogenesis clearly occurs with other agents in humans

  4. Magnetic mesoporous Fe/carbon aerogel structures with enhanced arsenic removal efficiency.

    Science.gov (United States)

    Lin, Yi-Feng; Chen, Jia-Ling

    2014-04-15

    Wastewater treatment has drawn significant research attention due to its associated environmental issues. Adsorption is a promising method for treating wastewater. The development of an adsorbent with a high surface area is important. Therefore, we successfully developed mesoporous Fe/carbon aerogel (CA) structures with high specific surface areas of 48 7m(2)/g via the carbonization of composite Fe3O4/phenol-formaldehyde resin structures, which were prepared using a hydrothermal process with the addition of phenol. The mesoporous Fe/CA structures were further used for the adsorption of arsenic ions with a maximum arsenic-ion uptake of calculated 216.9 mg/g, which is higher than that observed for other arsenic adsorbents. Ferromagnetic behavior was observed for the as-prepared mesoporous Fe/CA structures with an excellent response to applied external magnetic fields. As a result, the adsorbent Fe/CA structures can be easily separated from the solution using an external magnetic field. This study develops the mesoporous Fe/CA structures with high specific surface areas and an excellent response to an applied external magnetic field to provide a feasible approach for wastewater treatment including the removal of arsenic ions. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Arbuscular mycorrhiza differentially affects synthesis of essential oils in coriander and dill

    Czech Academy of Sciences Publication Activity Database

    Rydlová, Jana; Jelínková, M.; Dušek, K.; Dušková, E.; Vosátka, Miroslav; Püschel, David

    2016-01-01

    Roč. 26, č. 2 (2016), s. 123-131 ISSN 0940-6360 R&D Projects: GA MŠk 1M0571 Institutional support: RVO:67985939 Keywords : arbuscular mycorrhiza * aromatic plants * essential oils Subject RIV: EF - Botanics Impact factor: 3.047, year: 2016

  6. {sup 134}Cs in heather seed plants grown with and without mycorrhiza

    Energy Technology Data Exchange (ETDEWEB)

    Strandberg, M. [Risoe National Laboratory, DK-4000 Roskilde (Denmark); Johansson, M. [Department of Mycology, Botanical Institute, University of Copenhagen, Oester Farimagsgade 2D, DK-1353 Copenhagen K. (Denmark)

    1988-08-01

    Experiments were carried out to determine differences between mycorrhized and non-mycorrhized seed plants of heather, Calluna vulgaris(L)Hull, as regards the uptake of {sup 134}Cs. In most treatments heather with mycorrhiza had a significantly higher transfer of {sup 134}Cs to the shoots than heather without mycorrhiza. As an average the concentration of {sup 134}Cs was 18% higher in the mycorrhized plants than in the non-mycorrhized. Application of 10 kg K/ha reduced the concentration of {sup 134}Cs in shoots of heather by 49% as an average. Because of improved growth in the potassium fertilized pots the reduction viewed on the basis of the area was only 33%. Nitrogen application does not significantly influence the concentration of {sup 134}Cs in shoots of heather regardless of mycorrhizal status. (Copyright (c) 1988 Elsevier Science B.V., Amsterdam. All rights reserved.)

  7. The effect of vesicular-arbuscular mycorrhiza isolated from Syrian soil on alfalfa growth and nitrogen fixation in saline soil

    International Nuclear Information System (INIS)

    El Atrash, F

    2001-01-01

    The influence of vesicular - arbuscular Mycorrhiza fungi (VAM) on symbiotic fixation of N 2 n alfalfa plants has been observed. Beneficial effects of study the effect of VAM or phosphorous fertilization on alfalfa (Medicago sativa L,) yields, umber of nodules and N 2 fixation by N 15 isotope dilution at different salinity levels. This experiment was realized in green house conditions, using soil of 2.3 dsm -1 conductivity mixed with sand (5: 2V) for alfalfa plants growing at various levels of phosphorus, or infected by Mycorrhiza fungi. Different conductivities (13.18, 22.2, 28.8, 43.5 dsm -1 ) were applied on these treatment by increasing concentrations of Nacl, CaCl 2 and MgCl 2 and MgCl 2 by salinity soil irrigation. Ten days after planting, soil was enriched with 2 ppm of (NH 4 15 ) 2 SO 4 . Plant were grown under greenhouse condition for ten weeks. Our results confirmed that increased salinity reduced nitrogen - fixation and the number of nodules. The negative effect with increasing salinity was less in Mycorrhiza plants than in plants fertilized with various levels of phosphorus, and only the higher levels of salinity reduced significantly, the percentage of Mycorrhiza colonization, However, at all levels of salinity, VAM stimulated plant growth and nutrient uptake. (author)

  8. Phytoextraction by arsenic hyperaccumulator Pteris vittata L. from six arsenic-contaminated soils: Repeated harvests and arsenic redistribution

    Energy Technology Data Exchange (ETDEWEB)

    Gonzaga, Maria I.S.; Santos, Jorge A.G. [Department of Soil Chemistry, Universidade Federal da Bahia, Cruz das Almas, 44380000 (Brazil); Ma, Lena Q. [Soil and Water Science Department, University of Florida, 2169 McCarty Hall, Gainesville, FL 32611-0290 (United States)], E-mail: lqma@ifas.ufl.edu

    2008-07-15

    This greenhouse experiment evaluated arsenic removal by Pteris vittata and its effects on arsenic redistribution in soils. P. vittata grew in six arsenic-contaminated soils and its fronds were harvested and analyzed for arsenic in October, 2003, April, 2004, and October, 2004. The soil arsenic was separated into five fractions via sequential extraction. The ferns grew well and took up arsenic from all soils. Fern biomass ranged from 24.8 to 33.5 g plant{sup -1} after 4 months of growth but was reduced in the subsequent harvests. The frond arsenic concentrations ranged from 66 to 6,151 mg kg{sup -1}, 110 to 3,056 mg kg{sup -1}, and 162 to 2,139 mg kg{sup -1} from the first, second and third harvest, respectively. P. vittata reduced soil arsenic by 6.4-13% after three harvests. Arsenic in the soils was primarily associated with amorphous hydrous oxides (40-59%), which contributed the most to arsenic taken up by P. vittata (45-72%). It is possible to use P. vittata to remediate arsenic-contaminated soils by repeatedly harvesting its fronds. - Pteris vittata was effective in continuously removing arsenic from contaminated soils after three repeated harvests.

  9. Vesicular-Arbuscular Mycorrhiza in Field-Grown Crops

    DEFF Research Database (Denmark)

    Jakobsen, Iver

    1986-01-01

    The importance of vesicular-arbuscular mycorrhiza (VAM) and P fertilizer for P nutrition and dry matter production in field peas (Pisum sativum L.) was studied in moderately P-deficient soil. Half of the experimental plots were fumigated to reduce the level of VAM infection. Shoots and 0 to 30 cm...... in fumigated plots, although both it and P uptake were increased by adding P fertilizer. The possible reasons for this discrepancy are discussed. A supplementary survey on infection development at five other field sites showed that peas are extensively colonized by VAM fungi, even in soils where a standard...

  10. Arsenic pollution sources.

    Science.gov (United States)

    Garelick, Hemda; Jones, Huw; Dybowska, Agnieszka; Valsami-Jones, Eugenia

    2008-01-01

    Arsenic is a widely dispersed element in the Earth's crust and exists at an average concentration of approximately 5 mg/kg. There are many possible routes of human exposure to arsenic from both natural and anthropogenic sources. Arsenic occurs as a constituent in more than 200 minerals, although it primarily exists as arsenopyrite and as a constituent in several other sulfide minerals. The introduction of arsenic into drinking water can occur as a result of its natural geological presence in local bedrock. Arsenic-containing bedrock formations of this sort are known in Bangladesh, West Bengal (India), and regions of China, and many cases of endemic contamination by arsenic with serious consequences to human health are known from these areas. Significant natural contamination of surface waters and soil can arise when arsenic-rich geothermal fluids come into contact with surface waters. When humans are implicated in causing or exacerbating arsenic pollution, the cause can almost always be traced to mining or mining-related activities. Arsenic exists in many oxidation states, with arsenic (III) and (V) being the most common forms. Similar to many metalloids, the prevalence of particular species of arsenic depends greatly on the pH and redox conditions of the matrix in which it exists. Speciation is also important in determining the toxicity of arsenic. Arsenic minerals exist in the environment principally as sulfides, oxides, and phosphates. In igneous rocks, only those of volcanic origin are implicated in high aqueous arsenic concentrations. Sedimentary rocks tend not to bear high arsenic loads, and common matrices such as sands and sandstones contain lower concentrations owing to the dominance of quartz and feldspars. Groundwater contamination by arsenic arises from sources of arsenopyrite, base metal sulfides, realgar and orpiment, arsenic-rich pyrite, and iron oxyhydroxide. Mechanisms by which arsenic is released from minerals are varied and are accounted for by

  11. The role of bacteria and mycorrhiza in plant sulfur supply

    Directory of Open Access Journals (Sweden)

    Jacinta Mariea Gahan

    2014-12-01

    Full Text Available Plant growth is highly dependent on bacteria, saprophytic and mycorrhizal fungi which facilitate the cycling and mobilization of nutrients. Over 95% of the sulfur (S in soil is present in an organic form. Sulfate-esters and sulfonates, the major forms of organo-S in soils, arise through deposition of biological material and are transformed through subsequent humification. Fungi and bacteria release S from sulfate-esters using sulfatases, however, release of S from sulfonates is catalyzed by a bacterial multi-component mono-oxygenase system. The asfA gene is used as a key marker in this desulfonation process to study sulfonatase activity in soil bacteria identified as Variovorax, Polaromonas, Acidovorax and Rhodococcus. The rhizosphere is regarded as a hot spot for microbial activity and recent studies indicate that this is also the case for the mycorrhizosphere where bacteria may attach to the fungal hyphae capable of mobilizing organo-S. While current evidence is not showing sulfatase and sulfonatase activity in arbuscular mycorrhiza, their effect on the expression of plant host sulfate transporters is documented. A revision of the role of bacteria, fungi and the interactions between soil bacteria and mycorrhiza in plant S supply was conducted.

  12. [Mixture Leaching Remediation Technology of Arsenic Contaminated Soil].

    Science.gov (United States)

    Chen, Xun-feng; Li, Xiao-ming; Chen, Can; Yang, Qi; Deng, Lin-jing; Xie, Wei-qiang; Zhong, Yui; Huang, Bin; Yang, Wei-qiang; Zhang, Zhi-bei

    2016-03-15

    Soil contamination of arsenic pollution has become a severely environmental issue, while soil leaching is an efficient method for remediation of arsenic-contaminated soil. In this study, batch tests were primarily conducted to select optimal mixture leaching combination. Firstly, five conventional reagents were selected and combined with each other. Secondly, the fractions were analyzed before and after the tests. Finally, to explore the feasibility of mixed leaching, three soils with different arsenic pollution levels were used to compare the leaching effect. Comparing with one-step washing, the two-step sequential washing with different reagents increased the arsenic removal efficiency. These results showed that the mixture of 4 h 0.5 mol · L⁻¹ NaOH + 4 h 0.1 mol · L⁻¹ EDTA was found to be practicable, which could enhance the removal rate of arsenic from 66.67% to 91.83%, and the concentration of arsenic in soil was decreased from 186 mg · kg⁻¹ to 15.2 mg · kg⁻¹. Furthermore, the results indicated that the distribution of fractions of arsenic in soil changed apparently after mixture leaching. Leaching process could significantly reduce the available contents of arsenic in soil. Moreover, the mixture of 0.5 mol · L⁻¹ NaOH + 0.1 mol L⁻¹ EDTA could well decrease the arsenic concentration in aluminum-type soils, while the mixture of 0.5 mol · L⁻¹ OX + 0.5 mol · L⁻¹ NaOH could well decrease the arsenic concentration in iron-type soils.

  13. Urinary arsenic species, toenail arsenic, and arsenic intake estimates in a Michigan population with low levels of arsenic in drinking water.

    Science.gov (United States)

    Rivera-Núñez, Zorimar; Meliker, Jaymie R; Meeker, John D; Slotnick, Melissa J; Nriagu, Jerome O

    2012-01-01

    The large disparity between arsenic concentrations in drinking water and urine remains unexplained. This study aims to evaluate predictors of urinary arsenic in a population exposed to low concentrations (≤50 μg/l) of arsenic in drinking water. Urine and drinking water samples were collected from a subsample (n=343) of a population enrolled in a bladder cancer case-control study in southeastern Michigan. Total arsenic in water and arsenic species in urine were determined using ICP-MS: arsenobetaine (AsB), arsenite (As[III]), arsenate (As[V]), methylarsenic acid (MMA[V]), and dimethylarsenic acid (DMA[V]). The sum of As[III], As[V], MMA[V], and DMA[V] was denoted as SumAs. Dietary information was obtained through a self-reported food intake questionnaire. Log(10)-transformed drinking water arsenic concentration at home was a significant (Pwater were removed and further improved when analyses were applied to individuals who consumed amounts of home drinking water above the median volume (R(2)=0.40, Pwater was 0.42. Results show that arsenic exposure from drinking water consumption is an important determinant of urinary arsenic concentrations, even in a population exposed to relatively low levels of arsenic in drinking water, and suggest that seafood intake may influence urinary DMA[V] concentrations.

  14. Effect of combined inoculations of Rhizobium-Arbuscular Mycorrhiza in Leucaena leucocephala CV: Perú

    Directory of Open Access Journals (Sweden)

    Lázaro Jesús Ojeda Quintana

    2014-07-01

    Full Text Available The work was conducted at the Experimental Station of Soil and Fertilizer “Escambray” land of farmers and associated rural extension. The experimental design was randomized blocks, and treatments: Rizhobium loti V-4033 (Research Institute of Pastures and Forages, mycorrhizal fungi trainers, Rhizobium +mycorrhiza fungi trainers, nitrogen and total control. Inoculation with my corrhiza forming fungi was performed at 10 g/bag Certificate MicoFert Strain the Institute of Ecology and Systematics-3: Glomus spurcum, Topes de Collantes, 85 % colonization of rootlets, while the Rhizobium was inoculated in a dose of 50 g/kg of seed. Variant was nitrogen at 25 kg/ha of urea. The plots occupied 18m2 , with an area of 9 m2 evaluable. When the plants reached 7.5 months and an average height of 143.4 cm proceeded to make the Court of establishment and then four foliage cuts were made every 90 days. Each cut dry biomass yield, and phosphorus content was determined crude protein. The combined inoculation of Rhizobium and mycorrhiza fungi Makers increased the yield of dry biomass, and phosphorus content of crude protein. We conclude proposing the adoption of an alternative methodology using mycorrhiza formers Fungi and Rhizobium in Leucaena leucocephala as a way to increase the yield of dry biomass, decreasing mineral fertilization and contribute to environmental protection

  15. Soil Structure and Mycorrhizae Encourage Black Walnut Growth on Old Fields

    Science.gov (United States)

    Felix Jr. Ponder

    1979-01-01

    Examination of black walnut seedlings grown in forest and field soils showed all root systems were infected with mycorrhizae; the amount of infection was influenced by treatments. Mean height and dry weight of tops and roots were greater for seedlings grown in forest than field soil. Seedling height growth was not increased by disturbing either soil; but, root dry...

  16. The Effects of Arbuscular-Mycorrhizal Fungi and Phosphorous on Arsenic Uptake by Sunflower Plant in Soils Spiked with Arsenite and Arsenate

    Directory of Open Access Journals (Sweden)

    Saeed Bagherifam

    2017-01-01

    Full Text Available Introduction: Arsenic is a highly toxic metalloid in group 15 of periodic table. The information on environmental behaviour of arsenic, however, is still scarce. Contamination of soils and water with arsenic and antimony due to their widespread industrial application and mining activities has raised serious environmental concerns. Nearly all Arsenic-contaminated soils results from human activities and it has different environmental and sociological impacts. Various strategies and methods have been proposed for environmental management and remediation of contaminated soils. Among all methods, the phytoremediation is receiving more attention due to its cost effective and environmental friendly characteristics. In the case of arsenic contaminated soils, there are effective factors such as soil fertility, nutrients content and microorganisms function, which can improve the uptake of As by plants. Up to now, several studies have been evaluated the effects of symbiotic fungal association in plants on increasing nutrients and toxic elements uptake. Many of authors reported that the mycorrhizal symbiosis increases the uptake of toxic elements in root and shoot of plants and consequently improve the efficacy of phytostabilization and phytoextraction processes. There are conflicting results about the effect of arbuscular- mycorrhizal fungi (AMF on As uptake by various plants. Chen et al. (4 found that Glomus mosseae symbiosis with plant reduces As concentration and enhance phosphorus content in shoot and root of plant. Whilst Cozzolino et al. (7 reported that the AMF increases as concentration in shoot and root of cabbage. Phosphorus has important role on mycorrhizal symbiosis and also As uptake by plants. Therefore, current study was conducted to evaluated effect of Glomus intraradices and Glomus mosseae symbiosis with sunflower and also soil phosphorus concentration on uptake of arsenic from arsenite and arsenate contaminated soils. Materials and

  17. Ultramafic-derived arsenic in a fractured bedrock aquifer

    International Nuclear Information System (INIS)

    Ryan, Peter C.; Kim, Jonathan; Wall, Andrew J.; Moen, Jonathan C.; Corenthal, Lilly G.; Chow, Daniel R.; Sullivan, Colleen M.; Bright, Kevin S.

    2011-01-01

    Highlights: → Arsenic is elevated in groundwater from a fractured bedrock aquifer system in northern Vermont, USA. → The arsenic source is serpentinized ultramafic rock. → Antigorite, magnetite (MgCO 3 ) and magnetite (Fe 3 O 4 ) appear to be the main mineralogical hosts of arsenic in the ultramafic rock. → Arsenic appears to be introduced to the ultramafic rock when As-bearing fluids are driven out of sediments during subduction. → The occurrence of serpentinized ultramafic rocks in many orogenic belts suggests that similar arsenic anomalies may occur in geologically-similar terranes globally. - Abstract: In the fractured bedrock aquifer of northern Vermont, USA, As concentrations in groundwater range from 3 ) with lesser amounts in magnetite (Fe 3 O 4 ). Hydrochemistry of monitoring wells drilled into fractured ultramafic rock in a groundwater recharge area with no anthropogenic As source reveals above background As (2-9 μg/L) and an Mg-HCO 3 hydrochemical signature that reflects dissolution of antigorite and magnesite, confirming that As in groundwater can be derived from ultramafic rock dissolution. Arsenic mobility in groundwater affected by ultramafic rock dissolution may be enhanced by alkaline pH values and relatively high HCO 3 - concentrations.

  18. Effects of salt stress and mycorrhiza fungi on morpho-physiological characteristics of sweet corn

    Directory of Open Access Journals (Sweden)

    seyed Abdolreza kazemeini

    2017-06-01

    Full Text Available In order to investigate the interaction of mycorrhizal fungi and salinity on growth and physiological characteristics of sweet corn, a greenhouse experiment was conducted at College of Agriculture, Shiraz University, in 2014. The experimental design was factorial based on Completely Randomized Design in three replications. Treatments included salinity at four levels (0.4 (control, 4, 7, 10 dS m-1, and the fungi at three levels (no fungi (control, Glomus mosseae, Glomus intraradices. Results indicated that at flowering stage, with increasing salinity levels, leaf chlorophyll a, b and a+b content and carotenoid decreased at a rate of 18.9, 52.4, 33.1, and 34.5 respectively. Application of mycorrhiza under salinity, partially offset the negative impacts and increased tolerance of maize to NaCl by enhancing SOD and CAT activities, chlorophyll contents, carotenoid and K concentrations in leaves, plant height, leaf area, and total dry weight at flowering stage significantly, compared to control. The Na/K ratio at salinity level of 10 dS m-1 in treatments inoculated with GIN and GM fungi decreased by 39.69 and 40.45 percentage, respectively. Increases plant height, leaf area, total dry weight, concentrations of chlorophyll a, b, chlorophyll a+b and carotenoid and K, the activity of antioxidant enzymes compared with the control. Moreover, GIN type fungi had a greater advantage over GM and reduced the negative effects of salinity. Results indicated that application of mycorrhiza alleviated the adverse effect of salinity stress and improve the sweet corn dry weight up to 38 percentage at salinity level of 10 dS m-1.

  19. Unraveling the mechanism of neuroprotection of curcumin in arsenic induced cholinergic dysfunctions in rats

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, Pranay [CSIR-Indian Institute of Toxicology Research, Post Box 80, MG Marg, Lucknow 226 001 (India); Yadav, Rajesh S. [CSIR-Indian Institute of Toxicology Research, Post Box 80, MG Marg, Lucknow 226 001 (India); Department of Crimnology and Forensic Science, Harisingh Gour University, Sagar 470 003 (India); Chandravanshi, Lalit P.; Shukla, Rajendra K.; Dhuriya, Yogesh K.; Chauhan, Lalit K.S. [CSIR-Indian Institute of Toxicology Research, Post Box 80, MG Marg, Lucknow 226 001 (India); Dwivedi, Hari N. [Babu Banarasi Das University, BBD City, Faizabad Road, Lucknow 227 015 (India); Pant, Aditiya B. [CSIR-Indian Institute of Toxicology Research, Post Box 80, MG Marg, Lucknow 226 001 (India); Khanna, Vinay K., E-mail: vkkhanna1@gmail.com [CSIR-Indian Institute of Toxicology Research, Post Box 80, MG Marg, Lucknow 226 001 (India)

    2014-09-15

    Earlier, we found that arsenic induced cholinergic deficits in rat brain could be protected by curcumin. In continuation to this, the present study is focused to unravel the molecular mechanisms associated with the protective efficacy of curcumin in arsenic induced cholinergic deficits. Exposure to arsenic (20 mg/kg body weight, p.o) for 28 days in rats resulted to decrease the expression of CHRM2 receptor gene associated with mitochondrial dysfunctions as evident by decrease in the mitochondrial membrane potential, activity of mitochondrial complexes and enhanced apoptosis both in the frontal cortex and hippocampus in comparison to controls. The ultrastructural images of arsenic exposed rats, assessed by transmission electron microscope, exhibited loss of myelin sheath and distorted cristae in the mitochondria both in the frontal cortex and hippocampus as compared to controls. Simultaneous treatment with arsenic (20 mg/kg body weight, p.o) and curcumin (100 mg/kg body weight, p.o) for 28 days in rats was found to protect arsenic induced changes in the mitochondrial membrane potential and activity of mitochondrial complexes both in frontal cortex and hippocampus. Alterations in the expression of pro- and anti-apoptotic proteins and ultrastructural damage in the frontal cortex and hippocampus following arsenic exposure were also protected in rats simultaneously treated with arsenic and curcumin. The data of the present study reveal that curcumin could protect arsenic induced cholinergic deficits by modulating the expression of pro- and anti-apoptotic proteins in the brain. More interestingly, arsenic induced functional and ultrastructural changes in the brain mitochondria were also protected by curcumin. - Highlights: • Neuroprotective mechanism of curcumin in arsenic induced cholinergic deficits studied • Curcumin protected arsenic induced enhanced expression of stress markers in rat brain • Arsenic compromised mitochondrial electron transport chain protected

  20. Unraveling the mechanism of neuroprotection of curcumin in arsenic induced cholinergic dysfunctions in rats

    International Nuclear Information System (INIS)

    Srivastava, Pranay; Yadav, Rajesh S.; Chandravanshi, Lalit P.; Shukla, Rajendra K.; Dhuriya, Yogesh K.; Chauhan, Lalit K.S.; Dwivedi, Hari N.; Pant, Aditiya B.; Khanna, Vinay K.

    2014-01-01

    Earlier, we found that arsenic induced cholinergic deficits in rat brain could be protected by curcumin. In continuation to this, the present study is focused to unravel the molecular mechanisms associated with the protective efficacy of curcumin in arsenic induced cholinergic deficits. Exposure to arsenic (20 mg/kg body weight, p.o) for 28 days in rats resulted to decrease the expression of CHRM2 receptor gene associated with mitochondrial dysfunctions as evident by decrease in the mitochondrial membrane potential, activity of mitochondrial complexes and enhanced apoptosis both in the frontal cortex and hippocampus in comparison to controls. The ultrastructural images of arsenic exposed rats, assessed by transmission electron microscope, exhibited loss of myelin sheath and distorted cristae in the mitochondria both in the frontal cortex and hippocampus as compared to controls. Simultaneous treatment with arsenic (20 mg/kg body weight, p.o) and curcumin (100 mg/kg body weight, p.o) for 28 days in rats was found to protect arsenic induced changes in the mitochondrial membrane potential and activity of mitochondrial complexes both in frontal cortex and hippocampus. Alterations in the expression of pro- and anti-apoptotic proteins and ultrastructural damage in the frontal cortex and hippocampus following arsenic exposure were also protected in rats simultaneously treated with arsenic and curcumin. The data of the present study reveal that curcumin could protect arsenic induced cholinergic deficits by modulating the expression of pro- and anti-apoptotic proteins in the brain. More interestingly, arsenic induced functional and ultrastructural changes in the brain mitochondria were also protected by curcumin. - Highlights: • Neuroprotective mechanism of curcumin in arsenic induced cholinergic deficits studied • Curcumin protected arsenic induced enhanced expression of stress markers in rat brain • Arsenic compromised mitochondrial electron transport chain protected

  1. Complementary arsenic speciation methods: A review

    Energy Technology Data Exchange (ETDEWEB)

    Nearing, Michelle M., E-mail: michelle.nearing@rmc.ca; Koch, Iris, E-mail: koch-i@rmc.ca; Reimer, Kenneth J., E-mail: reimer-k@rmc.ca

    2014-09-01

    The toxicity of arsenic greatly depends on its chemical form and oxidation state (speciation) and therefore accurate determination of arsenic speciation is a crucial step in understanding its chemistry and potential risk. High performance liquid chromatography with inductively coupled mass spectrometry (HPLC–ICP-MS) is the most common analysis used for arsenic speciation but it has two major limitations: it relies on an extraction step (usually from a solid sample) that can be incomplete or alter the arsenic compounds; and it provides no structural information, relying on matching sample peaks to standard peaks. The use of additional analytical methods in a complementary manner introduces the ability to address these disadvantages. The use of X-ray absorption spectroscopy (XAS) with HPLC–ICP-MS can be used to identify compounds not extracted for HPLC–ICP-MS and provide minimal processing steps for solid state analysis that may help preserve labile compounds such as those containing arsenic-sulfur bonds, which can degrade under chromatographic conditions. On the other hand, HPLC–ICP-MS is essential in confirming organoarsenic compounds with similar white line energies seen by using XAS, and identifying trace arsenic compounds that are too low to be detected by XAS. The complementary use of electrospray mass spectrometry (ESI–MS) with HPLC–ICP-MS provides confirmation of arsenic compounds identified during the HPLC–ICP-MS analysis, identification of unknown compounds observed during the HPLC–ICP-MS analysis and further resolves HPLC–ICP-MS by identifying co-eluting compounds. In the complementary use of HPLC–ICP-MS and ESI–MS, HPLC–ICP-MS helps to focus the ESI–MS selection of ions. Numerous studies have shown that the information obtained from HPLC–ICP-MS analysis can be greatly enhanced by complementary approaches. - Highlights: • HPLC–ICP-MS is the most common method used for arsenic speciation. • HPLC limitations include

  2. Complementary arsenic speciation methods: A review

    International Nuclear Information System (INIS)

    Nearing, Michelle M.; Koch, Iris; Reimer, Kenneth J.

    2014-01-01

    The toxicity of arsenic greatly depends on its chemical form and oxidation state (speciation) and therefore accurate determination of arsenic speciation is a crucial step in understanding its chemistry and potential risk. High performance liquid chromatography with inductively coupled mass spectrometry (HPLC–ICP-MS) is the most common analysis used for arsenic speciation but it has two major limitations: it relies on an extraction step (usually from a solid sample) that can be incomplete or alter the arsenic compounds; and it provides no structural information, relying on matching sample peaks to standard peaks. The use of additional analytical methods in a complementary manner introduces the ability to address these disadvantages. The use of X-ray absorption spectroscopy (XAS) with HPLC–ICP-MS can be used to identify compounds not extracted for HPLC–ICP-MS and provide minimal processing steps for solid state analysis that may help preserve labile compounds such as those containing arsenic-sulfur bonds, which can degrade under chromatographic conditions. On the other hand, HPLC–ICP-MS is essential in confirming organoarsenic compounds with similar white line energies seen by using XAS, and identifying trace arsenic compounds that are too low to be detected by XAS. The complementary use of electrospray mass spectrometry (ESI–MS) with HPLC–ICP-MS provides confirmation of arsenic compounds identified during the HPLC–ICP-MS analysis, identification of unknown compounds observed during the HPLC–ICP-MS analysis and further resolves HPLC–ICP-MS by identifying co-eluting compounds. In the complementary use of HPLC–ICP-MS and ESI–MS, HPLC–ICP-MS helps to focus the ESI–MS selection of ions. Numerous studies have shown that the information obtained from HPLC–ICP-MS analysis can be greatly enhanced by complementary approaches. - Highlights: • HPLC–ICP-MS is the most common method used for arsenic speciation. • HPLC limitations include

  3. Arsenic implantation into polycrystalline silicon and diffusion to silicon substrate

    International Nuclear Information System (INIS)

    Tsukamoto, K.; Akasaka, Y.; Horie, K.

    1977-01-01

    Arsenic implantation into polycrystalline silicon and drive-in diffusion to silicon substrate have been investigated by MeV He + backscattering analysis and also by electrical measurements. The range distributions of arsenic implanted into polycrystalline silicon are well fitted to Gaussian distributions over the energy range 60--350 keV. The measured values of R/sub P/ and ΔR/sub P/ are about 10 and 20% larger than the theoretical predictions, respectively. The effective diffusion coefficient of arsenic implanted into polycrystalline silicon is expressed as D=0.63 exp[(-3.22 eV/kT)] and is independent of the arsenic concentration. The drive-in diffusion of arsenic from the implanted polycrystalline silicon layer into the silicon substrate is significantly affected by the diffusion atmosphere. In the N 2 atmosphere, a considerable amount of arsenic atoms diffuses outward to the ambient. The outdiffusion can be suppressed by encapsulation with Si 3 N 4 . In the oxidizing atmosphere, arsenic atoms are driven inward by growing SiO 2 due to the segregation between SiO 2 and polycrystalline silicon, and consequently the drive-in diffusion of arsenic is enhanced. At the interface between the polycrystalline silicon layer and the silicon substrate, arsenic atoms are likely to segregate at the polycrystalline silicon side

  4. The development and significance of vesicular-arbuscular mycorrhizas as influenced by agricultural practices

    NARCIS (Netherlands)

    Ruissen, M.A.

    1982-01-01

    The development and significance of vesicular- arbuscular mycorrhizas (VAM) in wheat and potatoes have been studied in relation to various farming systems and agricultural practices. The effects of farming systems on VAM have been observed on three neighbouring experimental farms in the vicinity of

  5. Arsenic trioxide sensitizes glioblastoma to a myc inhibitor.

    Directory of Open Access Journals (Sweden)

    Yayoi Yoshimura

    Full Text Available Glioblastoma multiforme (GBM is associated with high mortality due to infiltrative growth and recurrence. Median survival of the patients is less than 15 months, increasing requirements for new therapies. We found that both arsenic trioxide and 10058F4, an inhibitor of Myc, induced differentiation of cancer stem-like cells (CSC of GBM and that arsenic trioxide drastically enhanced the anti-proliferative effect of 10058F4 but not apoptotic effects. EGFR-driven genetically engineered GBM mouse model showed that this cooperative effect is higher in EGFRvIII-expressing INK4a/Arf-/- neural stem cells (NSCs than in control wild type NSCs. In addition, treatment of GBM CSC xenografts with arsenic trioxide and 10058F4 resulted in significant decrease in tumor growth and increased differentiation with concomitant decrease of proneural and mesenchymal GBM CSCs in vivo. Our study was the first to evaluate arsenic trioxide and 10058F4 interaction in GBM CSC differentiation and to assess new opportunities for arsenic trioxide and 10058F4 combination as a promising approach for future differentiation therapy of GBM.

  6. Arsenic exposure at low-to-moderate levels and skin lesions, arsenic metabolism, neurological functions, and biomarkers for respiratory and cardiovascular diseases: Review of recent findings from the Health Effects of Arsenic Longitudinal Study (HEALS) in Bangladesh

    International Nuclear Information System (INIS)

    Chen Yu; Parvez, Faruque; Gamble, Mary; Islam, Tariqul; Ahmed, Alauddin; Argos, Maria; Graziano, Joseph H.; Ahsan, Habibul

    2009-01-01

    The contamination of groundwater by arsenic in Bangladesh is a major public health concern affecting 35-75 million people. Although it is evident that high levels (> 300 μg/L) of arsenic exposure from drinking water are related to adverse health outcomes, health effects of arsenic exposure at low-to-moderate levels (10-300 μg/L) are not well understood. We established the Health Effects of Arsenic Longitudinal Study (HEALS) with more than 20,000 men and women in Araihazar, Bangladesh, to prospectively investigate the health effects of arsenic predominately at low-to-moderate levels (0.1 to 864 μg/L, mean 99 μg/L) of arsenic exposure. Findings to date suggest adverse effects of low-to-moderate levels of arsenic exposure on the risk of pre-malignant skin lesions, high blood pressure, neurological dysfunctions, and all-cause and chronic disease mortality. In addition, the data also indicate that the risk of skin lesion due to arsenic exposure is modifiable by nutritional factors, such as folate and selenium status, lifestyle factors, including cigarette smoking and body mass index, and genetic polymorphisms in genes related to arsenic metabolism. The analyses of biomarkers for respiratory and cardiovascular functions support that there may be adverse effects of arsenic on these outcomes and call for confirmation in large studies. A unique strength of the HEALS is the availability of outcome data collected prospectively and data on detailed individual-level arsenic exposure estimated using water, blood and repeated urine samples. Future prospective analyses of clinical endpoints and related host susceptibility will enhance our knowledge on the health effects of low-to-moderate levels of arsenic exposure, elucidate disease mechanisms, and give directions for prevention.

  7. Attenuation of arsenic neurotoxicity by curcumin in rats

    International Nuclear Information System (INIS)

    Yadav, Rajesh S.; Sankhwar, Madhu Lata; Shukla, Rajendra K.; Chandra, Ramesh; Pant, Aditya B.; Islam, Fakhrul; Khanna, Vinay K.

    2009-01-01

    In view of continued exposure to arsenic and associated human health risk including neurotoxicity, neuroprotective efficacy of curcumin, a polyphenolic antioxidant, has been investigated in rats. A significant decrease in locomotor activity, grip strength (26%) and rota-rod performance (82%) was observed in rats treated with arsenic (sodium arsenite, 20 mg/kg body weight, p.o., 28 days) as compared to controls. The arsenic treated rats also exhibited a decrease in the binding of striatal dopamine receptors (32%) and tyrosine hydroxylase (TH) immunoreactivity (19%) in striatum. Increased arsenic levels in corpus striatum (6.5 fold), frontal cortex (6.3 fold) and hippocampus (7.0 fold) associated with enhanced oxidative stress in these brain regions, as evident by an increase in lipid perioxidation, protein carbonyl and a decrease in the levels of glutathione and activity of superoxide dismutase, catalase and glutathione peroxidase with differential effects were observed in arsenic treated rats compared to controls. Simultaneous treatment with arsenic (sodium arsenite, 20 mg/kg body weight, p.o., 28 days) and curcumin (100 mg/kg body weight, p.o., 28 days) caused an increase in locomotor activity and grip strength and improved the rota-rod performance in comparison to arsenic treated rats. Binding of striatal dopamine receptors and TH expression increased while arsenic levels and oxidative stress decreased in these brain regions in co-treated rats as compared to those treated with arsenic alone. No significant effect on any of these parameters was observed in rats treated with curcumin (100 mg/kg body weight, p.o., 28 days) alone compared to controls. A significant protection in behavioral, neurochemical and immunohistochemical parameters in rats simultaneously treated with arsenic and curcumin suggest the neuroprotective efficacy of curcumin.

  8. Mycorrhizae and their potential use in the agricultural and forestry industries.

    Science.gov (United States)

    Peterson, R L; Piché, Y; Plenchette, C

    1984-01-01

    Mycorrhizal fungi associated with plant roots increase the absorption of nutrients, particularly phosphorus, and thus enhance the growth of crop plants and trees. Vesicular-arbuscular mycorrhizae (VAM) occur in approximately 90% of all vascular plants including most of the important agricultural species, whereas ectomycorrhizae are found in most of the economically important tree species of the temperate regions of the world, and in some tropical trees. These symbiotic associations are, therefore, important in crop and biomass production. For this reason they are receiving considerable attention in agriculture and forestry. Currently, VAM are utilized in fumigated soils, greenhouse crops, and in the reclamation of disturbed sites. Ectomycorrhizae are employed in the establishment of trees in nurseries, in reforestation programs, and in the production of containerized seedlings. Production of VAM and ectomycorrhiza inoculum for large scale projects is now feasible but many basic questions related to persistence of these fungi in field situations, competition with other microorganisms, and particularly the most efficient fungi to use for particular hosts remain largely unanswered.

  9. Raman spectra of thiolated arsenicals with biological importance.

    Science.gov (United States)

    Yang, Mingwei; Sun, Yuzhen; Zhang, Xiaobin; McCord, Bruce; McGoron, Anthony J; Mebel, Alexander; Cai, Yong

    2018-03-01

    Surface enhanced Raman scattering (SERS) has great potential as an alternative tool for arsenic speciation in biological matrices. SERS measurements have advantages over other techniques due to its ability to maintain the integrity of arsenic species and its minimal requirements for sample preparation. Up to now, very few Raman spectra of arsenic compounds have been reported. This is particularly true for thiolated arsenicals, which have recently been found to be widely present in humans. The lack of data for Raman spectra in arsenic speciation hampers the development of new tools using SERS. Herein, we report the results of a study combining the analysis of experimental Raman spectra with that obtained from density functional calculations for some important arsenic metabolites. The results were obtained with a hybrid functional B3LYP approach using different basis sets to calculate Raman spectra of the selected arsenicals. By comparing experimental and calculated spectra of dimethylarsinic acid (DMA V ), the basis set 6-311++G** was found to provide computational efficiency and precision in vibrational frequency prediction. The Raman frequencies for the rest of organoarsenicals were studied using this basis set, including monomethylarsonous acid (MMA III ), dimethylarsinous acid (DMA III ), dimethylmonothioarinic acid (DMMTA V ), dimethyldithioarsinic acid (DMDTA V ), S-(Dimethylarsenic) cysteine (DMA III (Cys)) and dimethylarsinous glutathione (DMA III GS). The results were compared with fingerprint Raman frequencies from As─O, As─C, and As─S obtained under different chemical environments. These fingerprint vibrational frequencies should prove useful in future measurements of different species of arsenic using SERS. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Phytoremediation of arsenic contaminated soil by arsenic accumulators: a three year study.

    Science.gov (United States)

    Raj, Anshita; Singh, Nandita

    2015-03-01

    To investigate whether phytoremediation can remove arsenic from the contaminated area, a study was conducted for three consecutive years to determine the efficiency of Pteris vittata, Adiantum capillus veneris, Christella dentata and Phragmites karka, on arsenic removal from the arsenic contaminated soil. Arsenic concentrations in the soil samples were analysed after harvesting in 2009, 2010 and 2011 at an interval of 6 months. Frond arsenic concentrations were also estimated in all the successive harvests. Fronds resulted in the greatest amount of arsenic removal. Root arsenic concentrations were analysed in the last harvest. Approximately 70 % of arsenic was removed by P. vittata which was recorded as the highest among the four plant species. However, 60 % of arsenic was removed by A. capillus veneris, 55.1 % by C. dentata and 56.1 % by P. karka of arsenic was removed from the contaminated soil in 3 years.

  11. Synthesis of magnetic wheat straw for arsenic adsorption

    International Nuclear Information System (INIS)

    Tian, Ye; Wu, Min; Lin, Xiaobo; Huang, Pei; Huang, Yong

    2011-01-01

    Highlights: → This work provides a way for fabricating low-cost arsenic adsorbents using agro- or plant-residues. → The introduction of wheat straw template highly enhances the arsenic adsorption of Fe 3 O 4 . → This magnetic adsorbent can be separated and collected by magnetic control easily and rapidly. → This adsorbent can be regenerated. → - Abstract: Magnetic wheat straw (MWS) with different Fe 3 O 4 content was synthesized by using in-situ co-precipitation method. It was characterized by powder X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). This material can be used for arsenic adsorption from water, and can be easily separated by applied magnetic field. The introduction of wheat straw template highly enhanced the arsenic adsorption of Fe 3 O 4 . Among three adsorption isotherm models examined, the data fitted Langmuir model better. Fe 3 O 4 content and initial pH value influenced its adsorption behavior. Higher Fe 3 O 4 content corresponded to a higher adsorption capacity. In the pH range of 3-11, As(V) adsorption was decreased with increasing of pH; As(III) adsorption had the highest capacity at pH 7-9. Moreover, by using 0.1 mol L -1 NaOH aqueous solution, it could be regenerated. This work provided an efficient way for making use of agricultural waste.

  12. Arsenic removal by magnetic nanocrystalline barium hexaferrite

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Hasmukh A.; Byun, Jeehye; Yavuz, Cafer T., E-mail: yavuz@kaist.ac.kr [Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST) (Korea, Republic of)

    2012-07-15

    Nanoscale magnetite (Fe{sub 3}O{sub 4}) (<15 nm) is known to remove arsenic efficiently but is very difficult to separate or require high magnetic fields to separate out from the waste water after treatment. Anisotropic hexagonal ferrite (BaFe{sub 12}O{sub 19}, BHF) is a well-known permanent magnet (i.e., fridge magnets) and attractive due to its low cost in making large quantities. BHF offers a viable alternative to magnetite nanocrystals for arsenic removal since it features surfaces similar to iron oxides but with much enhanced magnetism. Herein, we employ BHF nanocrystalline materials for the first time in arsenic removal from wastewater. Our results show better (75 %) arsenic removal than magnetite of the similar sizes. The BHF nanoparticles, 6.06 {+-} 0.52 nm synthesized by thermolysis method at 320 Degree-Sign C do not show hexagonal phase, however, subsequent annealing at 750 Degree-Sign C produced pure hexagonal BHF in >200 nm assemblies. By using BHF, we demonstrate that nanoparticle removal is more efficient and fixed bed type cartridge applications are more possible.

  13. The water relations of mycorrhiza

    International Nuclear Information System (INIS)

    Leyton, L.

    1982-01-01

    The wettability of the surface of ectotrophic beech mycorrhiza roots which did not have any radiating hyphae, was much less than a non-mycorrhizal root epidermis. The mycorrhizal sheath has a lower permeability to the flow of water than the uninfected root. The mycorrhizal roots absorbed water more rapidly than non-mycorrhizal roots. Possible explanations for this unusual phenomenon were (1) the development of a lower water potential in water stressed mycorrhizal roots, (2) accummulation of absorbed water in the sheath and (3) a higher permeability of the sheath to incoming than outgoing water. A study with endotrophic red clover plants confirmed that infection markedly increased growth and P uptake. This was accompanied by a reduction in the root/shoot ratio. This could be explained by a faster recovery of stressed mycorrhizal plants when water was restored because they were more efficient in taking up water. Experiments with tritiated water (THO) were initiated but consistent values for conductivity were not obtained. (author)

  14. Arsenic (+3 oxidation state) methyltransferase and the inorganic arsenic methylation phenotype

    International Nuclear Information System (INIS)

    Li Jiaxin; Waters, Stephen B.; Drobna, Zuzana; Devesa, Vicenta; Styblo, Miroslav; Thomas, David J.

    2005-01-01

    Inorganic arsenic is enzymatically methylated; hence, its ingestion results in exposure to the parent compound and various methylated arsenicals. Both experimental and epidemiological evidences suggest that some of the adverse health effects associated with chronic exposure to inorganic arsenic may be mediated by these methylated metabolites. If i As methylation is an activation process, then the phenotype for inorganic arsenic methylation may determine risk associated with exposure to this metalloid. We examined inorganic arsenic methylation phenotypes and arsenic (+3 oxidation state) methyltransferase genotypes in four species: three that methylate inorganic arsenic (human (Homo sapiens), rat (Rattus norwegicus), and mouse (Mus musculus)) and one that does not methylate inorganic arsenic (chimpanzee, Pan troglodytes). The predicted protein products from arsenic (+3 oxidation state) methyltransferase are similar in size for rat (369 amino acid residues), mouse (376 residues), and human (375 residues). By comparison, a 275-nucleotide deletion beginning at nucleotide 612 in the chimpanzee gene sequence causes a frameshift that leads to a nonsense mutation for a premature stop codon after amino acid 205. The null phenotype for inorganic arsenic methylation in the chimpanzee is likely due to the deletion in the gene for arsenic (+3 oxidation state) methyltransferase that yields an inactive truncated protein. This lineage-specific loss of function caused by the deletion event must have occurred in the Pan lineage after Homo-Pan divergence about 5 million years ago

  15. Uptake and speciation of selenium in garlic cultivated in soil amended with symbiotic fungi (mycorrhiza) and selenate

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Erik H.; Hansen, Marianne; Rasmussen, Peter Have; Sloth, Jens J. [Danish Institute for Food and Veterinary Research, Department of Food Chemistry, Soeborg (Denmark); Lobinski, Ryszard; Ruzik, Rafal; Mazurowska, Lena [CNRS UMR 5034, Pau (France); Warsaw University of Technology, Department of Analytical Chemistry, Warsaw (Poland); Burger-Meyer, Karin; Scholten, Olga [Wageningen University and Research Centre, Plant Research International (PRI), P.O. Box 16, Wageningen (Netherlands); Kik, Chris [Wageningen University and Research Centre, Plant Research International (PRI), P.O. Box 16, Wageningen (Netherlands); Wageningen University and Research Centre, Centre for Genetic Resources, The Netherlands (CGN), P.O. Box 16, Wageningen (Netherlands)

    2006-07-15

    The scope of the work was to investigate the influence of selenate fertilisation and the addition of symbiotic fungi (mycorrhiza) to soil on selenium and selenium species concentrations in garlic. The selenium species were extracted from garlic cultivated in experimental plots by proteolytic enzymes, which ensured liberation of selenium species contained in peptides or proteins. Separate extractions using an aqueous solution of enzyme-deactivating hydroxylamine hydrochloride counteracted the possible degradation of labile selenium species by enzymes (such as alliinase) that occur naturally in garlic. The selenium content in garlic, which was analysed by ICP-MS, showed that addition of mycorrhiza to the natural soil increased the selenium uptake by garlic tenfold to 15 {mu}g g{sup -1} (dry mass). Fertilisation with selenate and addition of mycorrhiza strongly increased the selenium content in garlic to around one part per thousand. The parallel analysis of the sample extracts by cation exchange and reversed-phase HPLC with ICP-MS detection showed that {gamma}-glutamyl-Se-methyl-selenocysteine amounted to 2/3, whereas methylselenocysteine, selenomethionine and selenate each amounted to a few percent of the total chromatographed selenium in all garlic samples. Se-allyl-selenocysteine and Se-propyl-selenocysteine, which are selenium analogues of biologically active sulfur-containing amino acids known to occur in garlic, were searched for but not detected in any of the extracts. The amendment of soil by mycorrhiza and/or by selenate increased the content of selenium but not the distribution of detected selenium species in garlic. Finally, the use of two-dimensional HPLC (size exclusion followed by reversed-phase) allowed the structural characterisation of {gamma}-glutamyl-Se-methyl-selenocysteine and {gamma}-glutamyl-Se-methyl-selenomethionine in isolated chromatographic fractions by quadrupole time-of-flight mass spectrometry. (orig.)

  16. Blood Pressure Associated with Arsenic Methylation and Arsenic Metabolism Caused by Chronic Exposure to Arsenic in Tube Well Water.

    Science.gov (United States)

    Wei, Bing Gan; Ye, Bi Xiong; Yu, Jiang Ping; Yang, Lin Sheng; Li, Hai Rong; Xia, Ya Juan; Wu, Ke Gong

    2017-05-01

    The effects of arsenic exposure from drinking water, arsenic metabolism, and arsenic methylation on blood pressure (BP) were observed in this study. The BP and arsenic species of 560 participants were determined. Logistic regression analysis was applied to estimate the odds ratios of BP associated with arsenic metabolites and arsenic methylation capability. BP was positively associated with cumulative arsenic exposure (CAE). Subjects with abnormal diastolic blood pressure (DBP), systolic blood pressure (SBP), and pulse pressure (PP) usually had higher urinary iAs (inorganic arsenic), MMA (monomethylated arsenic), DMA (dimethylated arsenic), and TAs (total arsenic) than subjects with normal DBP, SBP, and PP. The iAs%, MMA%, and DMA% differed slightly between subjects with abnormal BP and those with normal BP. The PMI and SMI were slightly higher in subjects with abnormal PP than in those with normal PP. Our findings suggest that higher CAE may elevate BP. Males may have a higher risk of abnormal DBP, whereas females have a higher risk of abnormal SBP and PP. Higher urinary iAs may increase the risk of abnormal BP. Lower PMI may elevate the BP. However, higher SMI may increase the DBP and SBP, and lower SMI may elevate the PP. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  17. Removal of arsenic from potable water by adsorptive media treatment techniques

    International Nuclear Information System (INIS)

    Yousuf, S.; Khan, S.; Aslam, M.T.; Khan, A.R.

    2012-01-01

    Summary: This study was conducted to investigate the arsenic removal efficiency of different adsorptive media from water. Different naturally occurring materials such as bauxite, plastic clay, plaster of Paris, lime, alum, and alumina etc. were used for the development of media to remove arsenic As/sup +5/ present in the artificially contaminated water. Different ratios of the selected materials were combined and ignited at 9000 C to enhance its arsenic removing efficiency. It was found that the media bauxite, plastic clay, lime (1:1:1) has a maximum removal (99%) of As +5 species from aqueous media and can be used on- site to reduce the arsenic contamination of potable water. Furthermore, the materials used in this experiment were cheaply and abundantly available within the country. The method is very simple and economically viable, for removal of arsenic from potable water. (author)

  18. Association of oxidative stress with arsenic methylation in chronic arsenic-exposed children and adults

    International Nuclear Information System (INIS)

    Xu Yuanyuan; Wang Yi; Zheng Quanmei; Li Xin; Li Bing; Jin Yaping; Sun Xiance; Sun Guifan

    2008-01-01

    Though oxidative stress is recognized as an important pathogenic mechanism of arsenic, and arsenic methylation capacity is suggested to be highly involved in arsenic-related diseases, the association of arsenic methylation capacity with arsenic-induced oxidative stress remains unclear. To explore oxidative stress and its association with arsenic methylation, cross-sectional studies were conducted among 208 high and 59 low arsenic-exposed subjects. Levels of urinary arsenic species [inorganic arsenic (iAs), monomethylated arsenic (MMA) and dimethylated arsenic (DMA)] were determined by hydride generation atomic absorption spectrometry. Proportions of urinary arsenic species, the first methylation ratio (FMR) and the secondary methylation ratio (SMR) were used as indicators for arsenic methylation capacity. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentrations were analyzed by enzyme-linked immunosorbent assay kits. Reduced glutathione (GSH) levels and superoxide dismutase (SOD) activity in whole blood were determined to reflect anti-oxidative status. The high arsenic-exposed children and adults were significantly increased in urinary 8-OHdG concentrations but decreased in blood GSH levels compared with the low exposed children and adults. In multiple linear regression models, blood GSH levels and urinary 8-OHdG concentrations of arsenic-exposed children and adults showed strong associations with the levels of urinary arsenic species. Arsenic-exposed subjects in the lower and the upper quartiles of proportions of urinary arsenic species, FMR or SMR were significantly different in urinary 8-OHdG, blood GSH and SOD. The associations of arsenic methylation capacity with 8-OHdG, GSH and SOD were also observed in multivariate regression analyses. These results may provide linkage between arsenic methylation capacity and oxidative stress in humans and suggest that adverse health effects induced by arsenic are related to arsenic methylation through oxidative stress

  19. Effect of Arbuscular Mycorrhiza Fungi and Pseudomonas fluorescent bactria on Nutrient Uptake of Pistachio Seedling (Pistacia Vera Cv. Qazvini under Four Irrigation Regimes

    Directory of Open Access Journals (Sweden)

    A. Shool

    2015-01-01

    Full Text Available Pistachio is one of the most important products exported from the country, which due to the low rainfall, its production is faced with water deficiency in Iran. One of the strategies adopted to deal with water deficiency and drought stress in recent years is the use of mycorrhizal fungi and phosphate solubilizing bacteria. Therefore, to study the effect of co-inoculation of arbuscular mycorrhizal fungus Glomus mosseae and Pseudomonas fluorescens P52 strain bacteria on nutrient uptake of pistachio seedling (Pistacia vera cv. Qazvini under drought stress, a greenhouse experiment was conducted using four levels of drought stress (%100 Field capacity (FC as control and 75, 50 and 25 %FC and four levels of biofertilizer (plant without mycorrhizae and bacteria as control, mycorrhizae alone (100 gr of mycorrhizal inoculum in every pot, bacteria alone (two ml of the bacterial suspension in every pot and mycorrhizae and bacteria combination (100 gr of mycorrhizal inoculum and two ml of the bacterial suspension in every pot in a completely randomized design as factorial with four replications. The experiment was carried out between the years of 2010 to 2011 on 3-months old seedlings with three seedlings per pot. In this experiment, bacteria inoculation in different levels of drought had no significant effect on root colonization by mycorrhizae, but regardless of bacterial treatment, an increase in drought intensity had a promotive effect on root colonization. The amount of phosphorus was increased using biofertilizer and in many cases the greatest amount of phosphorus was obtained in mycorrhizae and mixed treatments under 25 and 50% FC. The K+ content of shoot was maximum in the mixed treatment. The greatest amount of root Ca+ was recorded under 25% FC. Drought stress caused a significant increase in micronutrients compared with control at 25% of field capacity, but was ineffective in the roots. In conclusion, the results of this study showed that in many

  20. Chronic arsenic poisoning from burning high-arsenic-containing coal in Guizhou, China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J.; Zheng, B.S.; Aposhian, H.V.; Zhou, Y.S.; Chen, M.L.; Zhang, A.H.; Waalkes, M.P. [NIEHS, Research Triangle Park, NC (USA)

    2002-07-01

    Arsenic is an environmental hazard and the reduction of drinking water arsenic levels is under consideration. People are exposed to arsenic not only through drinking water but also through arsenic-contaminated air and food. Here the health effects of arsenic exposure from burning high arsenic-containing coal in Guizhou, China was investigated. Coal is burned inside the home in open pits for daily cooking and crop drying, producing a high concentration of arsenic in indoor air. Arsenic in the air coats and permeates food being dried producing high concentrations in food; however, arsenic concentrations in the drinking water are in the normal range. The estimated sources of total arsenic exposure in this area are from arsenic-contaminated food (50-80%), air (10-20%), water (1-5%), and direct contact in coal-mining workers (1%). At least 3,000 patients with arsenic poisoning were found in the Southwest Prefecture of Guizhou, and approximately 200,000 people are at risk for such over exposures. Skin lesions are common, including keratosis of the hands and feet, pigmentation on the trunk, skin ulceration, and skin cancers. Toxicities to internal organs, including lung dysfunction, neuropathy, and nephrotoxicity, are clinically evident. The prevalence of hepatomegaly was 20%, and cirrhosis, ascites, and liver cancer are the most serious outcomes of arsenic poisoning. The Chinese government and international organizations are attempting to improve the house conditions and the coal source, and thereby protect human health in this area.

  1. Absorption of foliar-applied arsenic by the arsenic hyperaccumulating fern (Pteris vittata L.)

    Energy Technology Data Exchange (ETDEWEB)

    Bondada, Bhaskar R.; Tu, Shuxin; Ma, Lena Q

    2004-10-01

    The fact that heavy metals can enter various domains of the plant system through foliar pathways spurred us to explore if the fronds of the Chinese brake fern (Pteris vittata L.), a hyperaccumulator of arsenic, a carcinogenic metalloid, was proficient in absorbing arsenic in the form of sprays. The specific objective of this study was to investigate the impact of frond age, form of arsenic, and time of application on the absorption of foliar-applied arsenic by the brake fern; also examined were the effects of foliar sprays on surface ultrastructure and arsenic speciation in the frond following absorption. Foliar sprays of different arsenic concentrations (0, 50, 100, 200, and 400 ppm) were applied to young and fertile fronds. A positive linear relationship existed between arsenic concentration and absorption; the arsenic concentration of fronds increased from 50 to 200 ppm. Time-course analysis with excised pinnae indicated an initial linear increase followed by a plateau at 48 h. The young fronds with immature sori absorbed more arsenic (3100 ppm) than the fertile mature fronds (890 ppm). In the frond, the arsenic absorption was greatest in the lamina of the pinnae followed by the sori and the rachis. Applying arsenic during night (20:00-22:00 h) or afternoon (12:00-14:00 h) resulted in greater absorption of arsenic than the application in the morning (08:00-10:00 h). The arsenic absorption was greater through abaxial surfaces than through adaxial surfaces. The brake fern absorbed more arsenic when it was applied in the form of arsenite. Regardless of the form of arsenic and the surface it was applied to, arsenic occurred as arsenite, the reduced and the most toxic form of arsenic, after having been absorbed by the fronds. Scanning electron microscopy revealed no surface morphological alterations following all arsenic sprays. The study unequivocally illustrated that the Chinese brake fern absorbed foliar-applied arsenic with great efficiency. Consequently, the

  2. Absorption of foliar-applied arsenic by the arsenic hyperaccumulating fern (Pteris vittata L.)

    International Nuclear Information System (INIS)

    Bondada, Bhaskar R.; Tu, Shuxin; Ma, Lena Q.

    2004-01-01

    The fact that heavy metals can enter various domains of the plant system through foliar pathways spurred us to explore if the fronds of the Chinese brake fern (Pteris vittata L.), a hyperaccumulator of arsenic, a carcinogenic metalloid, was proficient in absorbing arsenic in the form of sprays. The specific objective of this study was to investigate the impact of frond age, form of arsenic, and time of application on the absorption of foliar-applied arsenic by the brake fern; also examined were the effects of foliar sprays on surface ultrastructure and arsenic speciation in the frond following absorption. Foliar sprays of different arsenic concentrations (0, 50, 100, 200, and 400 ppm) were applied to young and fertile fronds. A positive linear relationship existed between arsenic concentration and absorption; the arsenic concentration of fronds increased from 50 to 200 ppm. Time-course analysis with excised pinnae indicated an initial linear increase followed by a plateau at 48 h. The young fronds with immature sori absorbed more arsenic (3100 ppm) than the fertile mature fronds (890 ppm). In the frond, the arsenic absorption was greatest in the lamina of the pinnae followed by the sori and the rachis. Applying arsenic during night (20:00-22:00 h) or afternoon (12:00-14:00 h) resulted in greater absorption of arsenic than the application in the morning (08:00-10:00 h). The arsenic absorption was greater through abaxial surfaces than through adaxial surfaces. The brake fern absorbed more arsenic when it was applied in the form of arsenite. Regardless of the form of arsenic and the surface it was applied to, arsenic occurred as arsenite, the reduced and the most toxic form of arsenic, after having been absorbed by the fronds. Scanning electron microscopy revealed no surface morphological alterations following all arsenic sprays. The study unequivocally illustrated that the Chinese brake fern absorbed foliar-applied arsenic with great efficiency. Consequently, the

  3. Arsenic removal by magnetic nanocrystalline barium hexaferrite

    International Nuclear Information System (INIS)

    Patel, Hasmukh A.; Byun, Jeehye; Yavuz, Cafer T.

    2012-01-01

    Nanoscale magnetite (Fe 3 O 4 ) ( 12 O 19 , BHF) is a well-known permanent magnet (i.e., fridge magnets) and attractive due to its low cost in making large quantities. BHF offers a viable alternative to magnetite nanocrystals for arsenic removal since it features surfaces similar to iron oxides but with much enhanced magnetism. Herein, we employ BHF nanocrystalline materials for the first time in arsenic removal from wastewater. Our results show better (75 %) arsenic removal than magnetite of the similar sizes. The BHF nanoparticles, 6.06 ± 0.52 nm synthesized by thermolysis method at 320 °C do not show hexagonal phase, however, subsequent annealing at 750 °C produced pure hexagonal BHF in >200 nm assemblies. By using BHF, we demonstrate that nanoparticle removal is more efficient and fixed bed type cartridge applications are more possible.

  4. Potential application of SERS for arsenic speciation in biological matrices.

    Science.gov (United States)

    Yang, Mingwei; Matulis, Shannon; Boise, Lawrence H; McGoron, Anthony J; Cai, Yong

    2017-08-01

    Speciation of arsenic is usually carried out using chromatography-based methods coupled with spectroscopic determination; however, the inevitable procedures involving sample preparation and separation could potentially alter the integrity of the arsenic metabolites present in biological samples. Surface-enhanced Raman spectroscopy (SERS) could be a promising alternative for providing a reliable arsenic analysis under the influence of a cellular matrix. A method for arsenic speciation using SERS in cellular matrix was developed in this study and four arsenicals were selected, including arsenite (As III ), arsenate (As V ), monomethylarsonic acid (MMA V ) and dimethylarsinic acid (DMA V ). Silver nanoparticles in the form of colliodal suspension with different surface charges, i.e., coated with citrate (AgNPs-Citrate) and spermine (AgNPs-Spermine) were employed as SERS substrates. Adsorption of arsenicals on nanoparticles in colloidal suspensions and the cellular matrix and the pH, size, and zeta potential of the colloidal suspensions were investigated for a better understanding of the SERS signal response of arsenicals in the colloidal suspensions or under the influence of cellular matrix. Arsenicals showed substantially different SERS responses in the two colloidal suspensions, mainly because of the distinct difference in the interaction between the arsenicals and the nanoparticles. Arsenic speciation in cell lysate could be successfully carried out in AgNPs-Spermine suspension, while AgNPs-Citrate could not yield significant SERS signals under the experimental conditions. This study proved that AgNPs-Spermine colloidal suspension could be a promising SERS substrate for studying arsenic metabolism in a biological matrix, reducing the bias caused by traditional techniques that involve sample extraction and pretreatment.

  5. Computational investigation of small RNAs in the establishment of root nodules and arbuscular mycorrhiza in leguminous plants.

    Science.gov (United States)

    Jin, Danfeng; Meng, Xianwen; Wang, Yue; Wang, Jingjing; Zhao, Yuhua; Chen, Ming

    2018-01-03

    Many small RNAs have been confirmed to play important roles in the development of root nodules and arbuscular mycorrhiza. In this study, we carried out the identification of certain small RNAs in leguminous plants (Medicago truncatula, soybean, peanut and common bean), such as miRNAs, tRFs and srRNAs, as well as the computational investigation of their regulations. Thirty miRNAs were predicted to be involved in establishing root nodules and mycorrhiza, and 12 of them were novel in common bean and peanut. The generation of tRFs in M. truncatula was not associated with tRNA gene frequencies and codon usage. Six tRFs exhibited different expressions in mycorrhiza and root nodules. Moreover, srRNA 5.8S in M. truncatula was generated from the regions with relatively low conservation at the rRNA 3' terminal. The protein-protein interactions between the proteins encoded by the target genes of miRNAs, tRFs and srRNAs were computed. The regulation of these three types of sRNAs in the symbiosis between leguminous plants and microorganisms is not a single regulation of certain signaling or metabolic pathways but a global regulation for the plants to own growth or specific events in symbiosis.

  6. Identification of arsenite-and arsenic diglutathione-binding proteins in human hepatocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Mizumura, Ayano; Watanabe, Takayuki [Graduate School of Pharmaceutical Sciences, Chiba University, Yayoi, Inage, Chiba 263-8522 (Japan); Kobayashi, Yayoi [Graduate School of Pharmaceutical Sciences, Chiba University, Yayoi, Inage, Chiba 263-8522 (Japan); Environmental Health Sciences Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Hirano, Seishiro [Graduate School of Pharmaceutical Sciences, Chiba University, Yayoi, Inage, Chiba 263-8522 (Japan); Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan)

    2010-01-15

    It is generally accepted that trivalent arsenicals are more toxic than the corresponding pentavalent arsenicals, since trivalent arsenicals bind the thiol groups of biomolecules, leading to a deterioration in cellular functions. In the present study, we prepared three different arsenic-bound sepharoses and investigated the binding of hepatic cytosolic proteins to pentavalent, trivalent, and glutathione-conjugated trivalent arsenicals. SDS-PAGE showed no proteins bound to pentavalent arsenic specifically. In contrast, we found a number of proteins that have specific and high affinity for trivalent arsenic. Two of those proteins were identified: protein disulfide isomerase-related protein 5 (PDSIRP5) and peroxiredoxin 1/enhancer protein (PRX1/EP). These proteins have vicinal cysteines, as previously reported. In contrast, one of the prominent proteins that did not bind to trivalent arsenic was identified as calreticulin precursor. Although there are 3 cysteines in calreticulin precursor, two of the cysteines are spaced more than 25 amino acids apart. Five synthetic peptides containing 2 vicinal cysteines were prepared to study whether they would inhibit the binding of PDSIRP5, PRX1/EP, and other arsenic-binding proteins to trivalent arsenicals. Only two of the five peptides effectively inhibited binding, suggesting that other amino acids besides the 2 vicinal cysteines may modulate the affinity of cysteine-rich proteins for trivalent arsenicals. We further investigated hepatic cytosolic proteins that bound specifically to glutathione-conjugated trivalent arsenic, which is the most abundant form of arsenical in bile fluid. Four proteins that bound specifically to glutathione-conjugated trivalent arsenic were identified; interestingly, these proteins were different from the trivalent arsenic-binding proteins. These results suggest that although glutathione-conjugation is an important process in the metabolism, excretion, and detoxification of arsenicals, glutathione

  7. Thorium coprecipitation method for spectrophotometric determination of arsenic (III) and arsenic (V) in groundwaters

    International Nuclear Information System (INIS)

    Tamari, Yuzo; Yamamoto, Nobuki; Tsuji, Haruo; Kusaka, Yuzuru

    1989-01-01

    A new coprecipitation method for the spectrophotometry of arsenic (III) and arsenic (V) in groundwater has been developed. Arsenic (III) and arsenic (V) were coprecipitated with thorium (IV) hydroxide from 1000ml of groundwater at pH9. The precipitate was centrifuged and then dissolved with hydrochloric acid. Arsenic (III) was spectrophotometrically determined by the usual silver diethylditiocarbamate (Ag-DDTC) method after generating the arsenic to arsine with sodium tetrahydroborate under masking the thorium with EDTA-NaF at pH6. From another portion of the same groundwater, both arsenic (III) and arsenic (V) were determined by the Ag-DDTC method after reducing all the arsenic to arsine with sodium tetrahydroborate at pH less than 1 in the presence of the EDTA-NaF. The concentration of arsenic (V) was obtained by subtracting that of arsenic (III) from the total for arsenic. (author)

  8. Developing robust arsenic awareness prediction models using machine learning algorithms.

    Science.gov (United States)

    Singh, Sushant K; Taylor, Robert W; Rahman, Mohammad Mahmudur; Pradhan, Biswajeet

    2018-04-01

    crucial role in arsenic awareness and outreach programs. Use of SVM or RF or a combination of the two, together with use of a larger sample size, could enhance the accuracy of arsenic awareness prediction. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Induction of glutathione synthesis in human hepatocytes by acute and chronic arsenic exposure: Differential roles of mitogen-activated protein kinases

    International Nuclear Information System (INIS)

    Hou, Yongyong; Wang, Yi; Wang, Huihui; Xu, Yuanyuan

    2014-01-01

    Highlights: • Arsenic exposure increased intracellular levels of glutathione. • Mitogen-activated protein kinases were involved in glutathione homeostasis. • ERK contributed to glutathione synthesis during acute arsenic exposure. • Glutathione synthesis was regulated by p38 at least in part independent of NRF2 during chronic arsenic exposure. - Abstract: Glutathione (GSH) is a vital component of antioxidant defense which protects cells from toxic insults. Previously we found intracellular GSH was involved in cell resistance against arsenic-induced cytotoxicity. However, molecular mechanisms of GSH homeostasis during arsenic exposure are largely undefined. Here, we investigated roles of mitogen-activated protein kinases (MAPKs) in GSH synthesis pathway with two arsenic exposure strategies by using Chang human hepatocytes. In one strategy, acute arsenic exposure (20 μM, 24 h) was applied, as MAPK signaling is generally considered to be transient. In the other one, chronic arsenic exposure (500 nM, 20 weeks) was applied, which mimicked the general human exposure to arsenic. We found that acute arsenic exposure activated extracellular signal-regulated 1/2 kinases (ERK1/2) and c-Jun N-terminal kinase (JNK) in parallel with increased transcription and nuclear translocation of factor-erythroid 2-related factor 2 (NRF2) and enhanced expression of γ-glutamyl cysteine ligase catalytic subunit (GCLC), resulting in elevated intracellular GSH levels. Specific ERK inhibitor abolished arsenic-induced NRF2 nuclear translocation and GSH synthesis. During chronic arsenic exposure which induced a malignant cellular phenotype, continuous p38 activation and NRF2 nuclear translocation were observed with enhanced GSH synthesis. Specific p38 inhibitor attenuated arsenic-enhanced GSH synthesis without changing NRF2 nuclear translocation. Taken together, our results indicate MAPK pathways play an important role in cellular GSH homeostasis in response to arsenic. However, the

  10. Roles of Arbuscular Mycorrhizas in Plant Phosphorus Nutrition: Interactions between Pathways of Phosphorus Uptake in Arbuscular Mycorrhizal Roots Have Important Implications for Understanding and Manipulating Plant Phosphorus Acquisition

    DEFF Research Database (Denmark)

    Smith, S.E.; Jakobsen, Iver; Grønlund, Mette

    2011-01-01

    In this Update, we review new findings about the roles of the arbuscular mycorrhizas (mycorrhiza = fungus plus root) in plant growth and phosphorus (P) nutrition. We focus particularly on the function of arbuscular mycorrhizal (AM) symbioses with different outcomes for plant growth (from positive...

  11. Biological monitoring of arsenic exposure of gallium arsenide- and inorganic arsenic-exposed workers by determination of inorganic arsenic and its metabolites in urine and hair

    Energy Technology Data Exchange (ETDEWEB)

    Yamauchi, H.; Takahashi, K.; Mashiko, M.; Yamamura, Y. (St. Marianna Univ. School of Medicine, Kawasaki (Japan))

    1989-11-01

    In an attempt to establish a method for biological monitoring of inorganic arsenic exposure, the chemical species of arsenic were measured in the urine and hair of gallium arsenide (GaAs) plant and copper smelter workers. Determination of urinary inorganic arsenic concentration proved sensitive enough to monitor the low-level inorganic arsenic exposure of the GaAs plant workers. The urinary inorganic arsenic concentration in the copper smelter workers was far higher than that of a control group and was associated with high urinary concentrations of the inorganic arsenic metabolites, methylarsonic acid (MAA) and dimethylarsinic acid (DMAA). The results established a method for exposure level-dependent biological monitoring of inorganic arsenic exposure. Low-level exposures could be monitored only by determining urinary inorganic arsenic concentration. High-level exposures clearly produced an increased urinary inorganic arsenic concentration, with an increased sum of urinary concentrations of inorganic arsenic and its metabolites (inorganic arsenic + MAA + DMAA). The determination of urinary arsenobetaine proved to determine specifically the seafood-derived arsenic, allowing this arsenic to be distinguished clearly from the arsenic from occupational exposure. Monitoring arsenic exposure by determining the arsenic in the hair appeared to be of value only when used for environmental monitoring of arsenic contamination rather than for biological monitoring.

  12. Expression profiles of defence related cDNAs in oil palm (Elaeis guineensis Jacq.) inoculated with mycorrhizae and Trichoderma harzianum Rifai T32.

    Science.gov (United States)

    Tan, Yung-Chie; Wong, Mui-Yun; Ho, Chai-Ling

    2015-11-01

    Basal stem rot is one of the major diseases of oil palm (Elaies guineensis Jacq.) caused by pathogenic Ganoderma species. Trichoderma and mycorrhizae were proposed to be able to reduce the disease severity. However, their roles in improving oil palm defence system by possibly inducing defence-related genes in the host are not well characterized. To better understand that, transcript profiles of eleven putative defence-related cDNAs in the roots of oil palm inoculated with Trichoderma harzianum T32 and mycorrhizae at different time points were studied. Transcripts encoding putative Bowman-Birk protease inhibitor (EgBBI2) and defensin (EgDFS) increased more than 2 fold in mycorrhizae-treated roots at 6 weeks post inoculation (wpi) compared to those in controls. Transcripts encoding putative dehydrin (EgDHN), glycine-rich RNA binding protein (EgGRRBP), isoflavone reductase (EgIFR), type 2 ribosome inactivating protein (EgT2RIP), and EgDFS increased in the oil palm roots treated with T. harzianum at 6 and/or 12 wpi compared to those in the controls. Some of these genes were also expressed in oil palm roots treated with Ganoderma boninense. This study provides an insight of some defence-related genes induced by Trichoderma and mycorrhizae, and their roles as potential agents to boost the plant defence system. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  13. Enhanced arsenic removal from water by hierarchically porous CeO₂-ZrO₂ nanospheres: role of surface- and structure-dependent properties.

    Science.gov (United States)

    Xu, Weihong; Wang, Jing; Wang, Lei; Sheng, Guoping; Liu, Jinhuai; Yu, Hanqing; Huang, Xing-Jiu

    2013-09-15

    Arsenic contaminated natural water is commonly used as drinking water source in some districts of Asia. To meet the increasingly strict drinking water standards, exploration of efficient arsenic removal methods is highly desired. In this study, hierarchically porous CeO₂-ZrO₂ nanospheres were synthesized, and their suitability as arsenic sorbents was examined. The CeO₂-ZrO₂ hollow nanospheres showed an adsorption capacity of 27.1 and 9.2 mg g(-1) for As(V) and As(III), respectively, at an equilibrium arsenic concentration of 0.01 mg L(-1) (the standard for drinking water) under neutral conditions, indicating a high arsenic removal performance of the adsorbent at low arsenic concentrations. Such a great arsenic adsorption capacity was attributed to the high surface hydroxyl density and presence of hierarchically porous network in the hollow nanospheres. The analysis of Fourier transformed infrared spectra and X-ray photoelectron spectroscopy demonstrated that the adsorption of arsenic on the CeO₂-ZrO₂ nanospheres was completed through the formation of a surface complex by substituting hydroxyl with arsenic species. In addition, the CeO₂-ZrO₂ nanospheres were able to remove over 97% arsenic in real underground water with initial arsenic concentration of 0.376 mg L(-1) to meet the guideline limit of arsenic in drinking water regulated by the World Health Organization without any pre-treatment and/or pH adjustment. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. The development of arbuscular mycorrhiza in two simulated stages of spoil-bank succession

    Czech Academy of Sciences Publication Activity Database

    Püschel, David; Rydlová, Jana; Vosátka, Miroslav

    2007-01-01

    Roč. 35, č. 2 (2007), s. 363-369 ISSN 0929-1393 R&D Projects: GA ČR GA526/04/0996; GA ČR(CZ) GD206/03/H137 Institutional research plan: CEZ:AV0Z60050516 Keywords : mycorrhiza * plant succession * spoil bank s Subject RIV: EF - Botanics Impact factor: 1.810, year: 2007

  15. Relation of soil nutrients and light to prevalence of mycorrhizae on pine seedlings

    Science.gov (United States)

    Edward Hacskaylo; Albert G., Jr. Snow

    1959-01-01

    Odd relationships abound among the wonders of Nature. Just as men keep cows, some ants herd aphids. The bee pays Nature for its food by pollinating the flower. One symbiotic relationship that concerns foresters is the coupling of tree roots with certain fungi to form compound structures, part tree root and part fungus mycelium, which we call mycorrhizae.

  16. Arsenic in Food

    Science.gov (United States)

    ... Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Food Home Food Foodborne Illness & Contaminants Metals Arsenic Share ... of the Method used to Measure Arsenic in Foods Inductively Coupled Plasma-Mass Spectrometric Determination of Arsenic, ...

  17. Injuries to Scots pine mycorrhizas and chemical gradients in forest soil in the environment of a pulp mill in Central Finland

    International Nuclear Information System (INIS)

    Holopaininen, T.; Heinonen-Tanski, H.; Halonen, A.

    1996-01-01

    The occurrence and condition of Scots pine mycorrhizas were studied at different distances from a pulp mill in Central Finland. The chemical analyses of the soil humus layer in the vicinity of the mill revealed increased levels of ammonium-nitrogen, sulphur and calcium but unaltered concentrations of phosphorus and magnesium. Higher nitrate levels and nitrification were clearly detected at some sites which had recently been limed. Significant decreases in root ramification index and number of living mycorrhizas were found in a 0-0.6 km zone surrounding the factory but these parameters increased with increasing distance. Within a 2 km zone around the mill there were abundant Cenococcum geophilus and Paxilus involutus-type mycorrhizas while lowered frequencies of several other mycorrhizal types were detected. An ultrastructural study revealed changes in several types of mycorrhizas, the clearest of which were increased tannin deposition in cortical cells, intracellular growth of hyphae in cortical cells and the appearance of electron dense accumulations in the vacuoles of the funal cells. The ultrastructural changes observed were distributed at least to a distance of 3 km from the mill and occurred in the roots of trees that had only a slight loss of needle mass. Nitrogen deposition is suspected to be the primary cause of root decline but atmospheric SO 2 through the tree crown is also likely to be a contributing factor. 37 refs., 10 figs., 7 tabs

  18. Risk of Erectile Dysfunction Induced by Arsenic Exposure through Well Water Consumption in Taiwan

    Science.gov (United States)

    Hsieh, Fang-I; Hwang, Ti-Sheng; Hsieh, Yi-Chen; Lo, Hsiu-Chiung; Su, Chien-Tien; Hsu, Hui-Shing; Chiou, Hung-Yi; Chen, Chien-Jen

    2008-01-01

    Background Erectile dysfunction (ED) has a profound impact on the quality of life of many men. Many risk factors are associated with ED, such as aging, sex hormone levels, hypertension, cardiovascular diseases, and diabetes mellitus. Arsenic exposure could damage peripheral vessels and increase the risk of cardiovascular disease. However, the relationship between arsenic exposure and ED has seldom been evaluated. Objectives In this study we aimed to investigate whether exposure to arsenic enhances the risk of ED. Methods We recruited 177 males ≥ 50 years of age through health examinations conducted in three hospitals in Taiwan. We used a questionnaire (International Index of Erectile Function-5) to measure the level of erectile function. Sex hormones, including total testosterone and sex hormone–binding globulin, were determined by radioimmunoassay. We used another standardized questionnaire to collect background and behavioral information (e.g., cigarette smoking; alcohol, tea, or coffee drinking; and physical activity). Results The prevalence of ED was greater in the arsenic-endemic area (83.3%) than in the non–arsenic-endemic area (66.7%). Subjects with arsenic exposure > 50 ppb had a significantly higher risk of developing ED than those with exposure ≤ 50 ppb, after adjusting for age, cigarette smoking, diabetes mellitus, hypertension, and cardiovascular disease [odds ratio (OR) = 3.4]. Results also showed that the risk of developing severe ED was drastically enhanced by arsenic exposure (OR = 7.5), after adjusting for free testosterone and traditional risk factors of ED. Conclusions Results suggested that chronic arsenic exposure has a negative impact on erectile function. PMID:18414639

  19. Detection of trace amount of arsenic in groundwater by laser-induced breakdown spectroscopy and adsorption

    Science.gov (United States)

    Haider, A. F. M. Y.; Hedayet Ullah, M.; Khan, Z. H.; Kabir, Firoza; Abedin, K. M.

    2014-03-01

    LIBS technique coupled with adsorption has been applied for the efficient detection of arsenic in liquid. Several adsorbents like tea leaves, bamboo slice, charcoal and zinc oxide have been used to enable sensitive detection of arsenic presence in water using LIBS. Among these, zinc oxide and charcoal show the better results. The detection limits for arsenic in water were 1 ppm and 8 ppm, respectively, when ZnO and charcoal were used as adsorbents of arsenic. To date, the determination of 1 ppm of As in water is the lowest concentration of detected arsenic in water by the LIBS technique. The detection limit of As was lowered to even less than 100 ppb by a combination of LIBS technique, adsorption by ZnO and concentration enhancement technique. Using the combination of these three techniques the ultimate concentration of arsenic was found to be 0.083 ppm (83 ppb) for arsenic polluted water collected from a tube-well of Farajikandi union (longitude 90.64°, latitude 23.338° north) of Matlab Upozila of Chandpur district in Bangladesh. This result compares fairly well with the finding of arsenic concentration of 0.078 ppm in the sample by the AAS technique at the Bangladesh Council of Scientific and Industrial Research (BCSIR) lab. Such a low detection limit (1 ppm) of trace elements in liquid matrix has significantly enhanced the scope of LIBS as an analytical tool.

  20. Arsenic Speciation and Extraction and the Significance of Biodegradable Acid on Arsenic Removal—An Approach for Remediation of Arsenic-Contaminated Soil

    Science.gov (United States)

    Nguyen Van, Thinh; Osanai, Yasuhito; Do Nguyen, Hai; Kurosawa, Kiyoshi

    2017-01-01

    A series of arsenic remediation tests were conducted using a washing method with biodegradable organic acids, including oxalic, citric and ascorbic acids. Approximately 80% of the arsenic in one sample was removed under the effect of the ascorbic and oxalic acid combination, which was roughly twice higher than the effectiveness of the ascorbic and citric acid combination under the same conditions. The soils treated using biodegradable acids had low remaining concentrations of arsenic that are primarily contained in the crystalline iron oxides and organic matter fractions. The close correlation between extracted arsenic and extracted iron/aluminum suggested that arsenic was removed via the dissolution of Fe/Al oxides in soils. The fractionation of arsenic in four contaminated soils was investigated using a modified sequential extraction method. Regarding fractionation, we found that most of the soil contained high proportions of arsenic (As) in exchangeable fractions with phosphorus, amorphous oxides, and crystalline iron oxides, while a small amount of the arsenic fraction was organic matter-bound. This study indicated that biodegradable organic acids can be considered as a means for arsenic-contaminated soil remediation.

  1. Effects of different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower under water stress

    Directory of Open Access Journals (Sweden)

    Mostafa Heidari

    2014-01-01

    Full Text Available The role of arbuscular mycorrhizal fungi in alleviating water stress is well documented. In order to study the effects of water stress and two different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower, a field experiment as split plot design with three replications was conducted in the Research Field Station, Zabol University, Zabol, Iran in 2011. Water stress treatments included control as 90% of field capacity (W1, 70% field capacity (W2 and 50% field capacity (W3 assigned to the main plots and two different mycorrhiza species, consisting of M1 = control (without any inoculation, M2 = Glumus mossea and M3 = Glumus etanicatum as sub plots. Results showed that by increasing water stress from control (W1 to W3 treatment, grain yield was significantly decreased. The reduction in the level of W3 was 15.05%. The content of potassium in seeds significantly decreased due to water stress but water stress upto W2 treatment increased the content of phosphorus, nitrogen and oil content of seeds. In between two species of mycorrhiza in sunflower plants, Glumus etanicatum had the highest effect on grain yield and these elements in seeds and increased both.

  2. A Simple Metallothionein-Based Biosensor for Enhanced Detection of Arsenic and Mercury

    Directory of Open Access Journals (Sweden)

    Gordon W. Irvine

    2017-03-01

    Full Text Available Metallothioneins (MTs are a family of cysteine-rich proteins whose biological roles include the regulation of essential metal ions and protection against the harmful effects of toxic metals. Due to its high affinity for many toxic, soft metals, recombinant human MT isoform 1a was incorporated into an electrochemical-based biosensor for the detection of As3+ and Hg2+. A simple design was chosen to maximize its potential in environmental monitoring and MT was physically adsorbed onto paper discs placed on screen-printed carbon electrodes (SPCEs. This system was tested with concentrations of arsenic and mercury typical of contaminated water sources ranging from 5 to 1000 ppb. The analytical performance of the MT-adsorbed paper discs on SPCEs demonstrated a greater than three-fold signal enhancement and a lower detection limit compared to blank SPCEs, 13 ppb for As3+ and 45 ppb for Hg2+. While not being as low as some of the recommended drinking water limits, the sensitivity of the simple MT-biosensor would be potentially useful in monitoring of areas of concern with a known contamination problem. This paper describes the ability of the metal binding protein metallothionein to enhance the effectiveness of a simple, low-cost electrochemical sensor.

  3. The effect of arsenic contamination on amino acids metabolism in Spinacia oleracea L.

    Science.gov (United States)

    Pavlík, Milan; Pavlíková, Daniela; Staszková, Ludmila; Neuberg, Marek; Kaliszová, Regina; Száková, Jirina; Tlustos, Pavel

    2010-09-01

    Changes of amino acid concentrations (proline, glutamate, asparagine, aspartate, alanine) and glutamate kinase activity (GKA) in plants under arsenic chronic stress reported here reveal their role in plant arsenic stress adaptation. Results of the pot experiment confirmed the toxic effect of arsenic at tested levels (As1=25 mg As kg(-1) soil, As2=50 mg As kg(-1) soil, As3=75 mg As kg(-1) soil) for spinach. Growing available arsenic contents in soil were associated with the strong inhibition of above-ground biomass and with the enhancement of As plant content. The changes of glutamate, asparagine, aspartate and proline levels in the plants showed strong linear dependences on arsenic concentration in plants (R2=0.60-0.90). Compared to the untreated control, concentrations of free proline and aspartate of As3 treatment were enhanced up to 381% and 162%, respectively. The significant changes of glutamate were observed on As2 and As3 treatments (increased level up to 188, i.e. 617%). Arsenic in plants was shown to be an inhibitor of glutamase kinase activity (R2=0.91). Inhibition of GKA resulted in an increase in the content of glutamate that is used in synthesis of phytochelatins in plant cells. Concentration of alanine did not have a confirmed linear dependence on arsenic concentration in plant (R2=0.05). The changes of its concentrations could be affected by changes of pH in plant cell or induction of alanine aminotransferase by hypoxia. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  4. The antitumor effect of arsenic trioxide on hepatocellular carcinoma is enhanced by andrographolide.

    Science.gov (United States)

    Duan, Xuhua; Li, Tengfei; Han, Xinwei; Ren, Jianzhuang; Chen, Pengfei; Li, Hao; Gong, Shaojun

    2017-10-31

    High concentrations of arsenic trioxide (As 2 O 3 ) are used to treat acute promyelocytic leukemia and solid tumors, with negative side effects to normal cells. Andrographolide is a traditional Chinese medicine that exerts anti-cancer, anti-inflammatory, anti-virus, and anti-diabetic effects. Here, we tested the effects of combined andrographolide with As 2 O 3 against hepatocellular carcinoma (HCC). We found that by increasing apoptosis, andrographolide synergistically enhanced the anti-tumor effects of As2O3 in HepG2 cells in vitro and in vivo . Furthermore, results from our microarray assays and experiments with mouse xenografts showed that EphB4 was downregulated by the combination of As 2 O 3 plus andrographolide. These findings suggest that the combination of andrographolide and As 2 O 3 could yield therapeutic benefits in the treatment of HCC.

  5. Understanding arsenic metabolism through spectroscopic determination of arsenic in human urine

    OpenAIRE

    Brima, Eid I.; Jenkins, Richard O.; Haris, Parvez I.

    2006-01-01

    In this review we discuss a range of spectroscopic techniques that are currently used for analysis of arsenic in human urine for understanding arsenic metabolism and toxicity, especially in relation to genetics/ethnicity, ingestion studies and exposure to arsenic through drinking water and diet. Spectroscopic techniques used for analysis of arsenic in human urine include inductively coupled plasma mass spectrometry (ICP-MS), hydride generation atomic absorption spectrometry (HG-AAS), hydride ...

  6. Oligofructose protects against arsenic-induced liver injury in a model of environment/obesity interaction

    Energy Technology Data Exchange (ETDEWEB)

    Massey, Veronica L. [Department of Pharmacology and Toxicology, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); Stocke, Kendall S. [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); Schmidt, Robin H.; Tan, Min [Department of Pharmacology and Toxicology, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); Ajami, Nadim [Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX (United States); Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX (United States); Neal, Rachel E. [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); Petrosino, Joseph F. [Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX (United States); Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX (United States); Barve, Shirish [Department of Medicine, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); Arteel, Gavin E., E-mail: gavin.arteel@louisville.edu [Department of Pharmacology and Toxicology, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States)

    2015-05-01

    Arsenic (As) tops the ATSDR list of hazardous environmental chemicals and is known to cause liver injury. Although the concentrations of As found in the US water supply are generally too low to directly damage the liver, subhepatotoxic doses of As sensitize the liver to experimental NAFLD. It is now suspected that GI microbiome dysbiosis plays an important role in development of NALFD. Importantly, arsenic has also been shown to alter the microbiome. The purpose of the current study was to test the hypothesis that the prebiotic oligofructose (OFC) protects against enhanced liver injury caused by As in experimental NAFLD. Male C57Bl6/J mice were fed low fat diet (LFD), high fat diet (HFD), or HFD containing oligofructose (OFC) during concomitant exposure to either tap water or As-containing water (4.9 ppm as sodium arsenite) for 10 weeks. HFD significantly increased body mass and caused fatty liver injury, as characterized by an increased liver weight-to-body weight ratio, histologic changes and transaminases. As observed previously, As enhanced HFD-induced liver damage, which was characterized by enhanced inflammation. OFC supplementation protected against the enhanced liver damage caused by As in the presence of HFD. Interestingly, arsenic, HFD and OFC all caused unique changes to the gut flora. These data support previous findings that low concentrations of As enhance liver damage caused by high fat diet. Furthermore, these results indicate that these effects of arsenic may be mediated, at least in part, by GI tract dysbiosis and that prebiotic supplementation may confer significant protective effects. - Highlights: • Arsenic (As) enhances liver damage caused by a high-fat (HFD) diet in mice. • Oligofructose protects against As-enhanced liver damage caused by HFD. • As causes dysbiosis in the GI tract and exacerbates the dysbiosis caused by HFD. • OFC prevents the dysbiosis caused by HFD and As, increasing commensal bacteria.

  7. Oligofructose protects against arsenic-induced liver injury in a model of environment/obesity interaction

    International Nuclear Information System (INIS)

    Massey, Veronica L.; Stocke, Kendall S.; Schmidt, Robin H.; Tan, Min; Ajami, Nadim; Neal, Rachel E.; Petrosino, Joseph F.; Barve, Shirish; Arteel, Gavin E.

    2015-01-01

    Arsenic (As) tops the ATSDR list of hazardous environmental chemicals and is known to cause liver injury. Although the concentrations of As found in the US water supply are generally too low to directly damage the liver, subhepatotoxic doses of As sensitize the liver to experimental NAFLD. It is now suspected that GI microbiome dysbiosis plays an important role in development of NALFD. Importantly, arsenic has also been shown to alter the microbiome. The purpose of the current study was to test the hypothesis that the prebiotic oligofructose (OFC) protects against enhanced liver injury caused by As in experimental NAFLD. Male C57Bl6/J mice were fed low fat diet (LFD), high fat diet (HFD), or HFD containing oligofructose (OFC) during concomitant exposure to either tap water or As-containing water (4.9 ppm as sodium arsenite) for 10 weeks. HFD significantly increased body mass and caused fatty liver injury, as characterized by an increased liver weight-to-body weight ratio, histologic changes and transaminases. As observed previously, As enhanced HFD-induced liver damage, which was characterized by enhanced inflammation. OFC supplementation protected against the enhanced liver damage caused by As in the presence of HFD. Interestingly, arsenic, HFD and OFC all caused unique changes to the gut flora. These data support previous findings that low concentrations of As enhance liver damage caused by high fat diet. Furthermore, these results indicate that these effects of arsenic may be mediated, at least in part, by GI tract dysbiosis and that prebiotic supplementation may confer significant protective effects. - Highlights: • Arsenic (As) enhances liver damage caused by a high-fat (HFD) diet in mice. • Oligofructose protects against As-enhanced liver damage caused by HFD. • As causes dysbiosis in the GI tract and exacerbates the dysbiosis caused by HFD. • OFC prevents the dysbiosis caused by HFD and As, increasing commensal bacteria

  8. Chronic Arsenic Toxicity: Statistical Study of the Relationships Between Urinary Arsenic, Selenium and Antimony

    OpenAIRE

    Analía Boemo, BS; Irene María Lomniczi, PhD; Elsa Mónica Farfán Torres, PhD

    2012-01-01

    Background. The groundwater of Argentina’s Chaco plain presents arsenic levels above those suitable for human consumption. Studies suggest skin disorders among local populations caused by arsenic intake. The relationship between urinary arsenic and arsenic in drinking water is well known, but urinary arsenic alone is not enough for risk assessment due to modulating factors such as the intake of selenium and antimony. Objectives. Determining the relationship between urinary arsenic, seleniu...

  9. Plants as useful vectors to reduce environmental toxic arsenic content.

    Science.gov (United States)

    Mirza, Nosheen; Mahmood, Qaisar; Maroof Shah, Mohammad; Pervez, Arshid; Sultan, Sikander

    2014-01-01

    Arsenic (As) toxicity in soil and water is an increasing menace around the globe. Its concentration both in soil and environment is due to natural and anthropogenic activities. Rising arsenic concentrations in groundwater is alarming due to the health risks to plants, animals, and human beings. Anthropogenic As contamination of soil may result from mining, milling, and smelting of copper, lead, zinc sulfide ores, hide tanning waste, dyes, chemical weapons, electroplating, gas exhaust, application of municipal sludge on land, combustion of fossil fuels, As additives to livestock feed, coal fly ash, and use of arsenical pesticides in agricultural sector. Phytoremediation can be viewed as biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system) that enhances the natural ecosystems for subsequent productive use. The present review presents recent scientific developments regarding phytoremediation of arsenic contaminated environments and its possible detoxification mechanisms in plants.

  10. Matrix modification with silver for the electrothermal atomization of arsenic and selenium

    Science.gov (United States)

    Sanzolone, R.F.; Chao, T.T.

    1981-01-01

    Silver as a matrix modifier is shown to improve the carbon-rod atomization of both arsenic and selenium for atomic absorption spectrometry. Compared to nickel, the efficiency of silver is greater for arsenic and about the same for selenium. Silver fulfils two functions in its reaction, namely stabilization during the ashing stage and enhancement of absorbance in the final atomization. ?? 1981.

  11. Approaches to increase arsenic awareness in Bangladesh: an evaluation of an arsenic education program.

    Science.gov (United States)

    George, Christine Marie; Factor-Litvak, Pam; Khan, Khalid; Islam, Tariqul; Singha, Ashit; Moon-Howard, Joyce; van Geen, Alexander; Graziano, Joseph H

    2013-06-01

    The objective of this study was to design and evaluate a household-level arsenic education and well water arsenic testing intervention to increase arsenic awareness in Bangladesh. The authors randomly selected 1,000 study respondents located in 20 villages in Singair, Bangladesh. The main outcome was the change in knowledge of arsenic from baseline to follow-up 4 to 6 months after the household received the intervention. This was assessed through a pre- and postintervention quiz concerning knowledge of arsenic. Respondents were between 18 and 102 years of age, with an average age of 37 years; 99.9% were female. The knowledge of arsenic quiz scores for study participants were significantly higher at follow-up compared with baseline. The intervention was effective in increasing awareness of the safe uses of arsenic-contaminated water and dispelling the misconception that boiling water removes arsenic. At follow-up, nearly all respondents were able to correctly identify the meaning of a red (contaminated) and green (arsenic safe) well relative to arsenic (99%). The educational program also significantly increased the proportion of respondents who were able to correctly identify the health implications of arsenic exposure. However, the intervention was not effective in dispelling the misconceptions in the population that arsenicosis is contagious and that illnesses such as cholera, diarrhea, and vomiting could be caused by arsenic. Further research is needed to develop effective communication strategies to dispel these misconceptions. This study demonstrates that a household-level arsenic educational program can be used to significantly increase arsenic awareness in Bangladesh.

  12. Arsenic speciation in saliva of acute promyelocytic leukemia patients undergoing arsenic trioxide treatment

    OpenAIRE

    Chen, Baowei; Cao, Fenglin; Yuan, Chungang; Lu, Xiufen; Shen, Shengwen; Zhou, Jin; Le, X. Chris

    2013-01-01

    Arsenic trioxide has been successfully used as a therapeutic in the treatment of acute promyelocytic leukemia (APL). Detailed monitoring of the therapeutic arsenic and its metabolites in various accessible specimens of APL patients can contribute to improving treatment efficacy and minimizing arsenic-induced side effects. This article focuses on the determination of arsenic species in saliva samples from APL patients undergoing arsenic treatment. Saliva samples were collected from nine APL pa...

  13. Arsenic tolerance in Arabidopsis is mediated by two ABCC-type phytochelatin transporters

    Science.gov (United States)

    Song, Won-Yong; Park, Jiyoung; Mendoza-Cózatl, David G.; Suter-Grotemeyer, Marianne; Shim, Donghwan; Hörtensteiner, Stefan; Geisler, Markus; Weder, Barbara; Rea, Philip A.; Rentsch, Doris; Schroeder, Julian I.; Lee, Youngsook; Martinoia, Enrico

    2010-01-01

    Arsenic is an extremely toxic metalloid causing serious health problems. In Southeast Asia, aquifers providing drinking and agricultural water for tens of millions of people are contaminated with arsenic. To reduce nutritional arsenic intake through the consumption of contaminated plants, identification of the mechanisms for arsenic accumulation and detoxification in plants is a prerequisite. Phytochelatins (PCs) are glutathione-derived peptides that chelate heavy metals and metalloids such as arsenic, thereby functioning as the first step in their detoxification. Plant vacuoles act as final detoxification stores for heavy metals and arsenic. The essential PC–metal(loid) transporters that sequester toxic metal(loid)s in plant vacuoles have long been sought but remain unidentified in plants. Here we show that in the absence of two ABCC-type transporters, AtABCC1 and AtABCC2, Arabidopsis thaliana is extremely sensitive to arsenic and arsenic-based herbicides. Heterologous expression of these ABCC transporters in phytochelatin-producing Saccharomyces cerevisiae enhanced arsenic tolerance and accumulation. Furthermore, membrane vesicles isolated from these yeasts exhibited a pronounced arsenite [As(III)]–PC2 transport activity. Vacuoles isolated from atabcc1 atabcc2 double knockout plants exhibited a very low residual As(III)–PC2 transport activity, and interestingly, less PC was produced in mutant plants when exposed to arsenic. Overexpression of AtPCS1 and AtABCC1 resulted in plants exhibiting increased arsenic tolerance. Our findings demonstrate that AtABCC1 and AtABCC2 are the long-sought and major vacuolar PC transporters. Modulation of vacuolar PC transporters in other plants may allow engineering of plants suited either for phytoremediation or reduced accumulation of arsenic in edible organs. PMID:21078981

  14. Enhanced removal of arsenic from a highly laden industrial effluent using a combined coprecipitation/nano-adsorption process.

    Science.gov (United States)

    Jiang, Yingnan; Hua, Ming; Wu, Bian; Ma, Hongrui; Pan, Bingcai; Zhang, Quanxing

    2014-05-01

    Effective arsenic removal from highly laden industrial wastewater is an important but challenging task. Here, a combined coprecipitation/nano-adsorption process, with ferric chloride and calcium chloride as coprecipitation agents and polymer-based nanocomposite as selective adsorbent, has been validated for arsenic removal from tungsten-smelting wastewater. On the basis of operating optimization, a binary FeCl3 (520 mg/L)-CaCl2 (300 mg/L) coprecipitation agent could remove more than 93% arsenic from the wastewater. The resulting precipitate has proved environmental safety based on leaching toxicity test. Fixed-bed column packed with zirconium or ferric-oxide-loaded nanocomposite was employed for further elimination of arsenic in coprecipitated effluent, resulting in a significant decrease of arsenic (from 0.96 to less than 0.5 mg/L). The working capacity of zirconium-loaded nanocomposite was 220 bed volumes per run, much higher than that of ferric-loaded nanocomposite (40 bed volumes per run). The exhausted zirconium-loaded nanocomposite could be efficiently in situ regenerated with a binary NaOH-NaCl solution for reuse without any significant capacity loss. The results validated the combinational coprecipitation/nano-adsorption process to be a potential alternative for effective arsenic removal from highly laden industrial effluent.

  15. A Potential Synergy between Incomplete Arsenic Methylation Capacity and Demographic Characteristics on the Risk of Hypertension: Findings from a Cross-Sectional Study in an Arsenic-Endemic Area of Inner Mongolia, China

    Directory of Open Access Journals (Sweden)

    Yongfang Li

    2015-03-01

    Full Text Available Inefficient arsenic methylation capacity has been associated with various health hazards induced by arsenic. In this study, we aimed to explore the interaction effect of lower arsenic methylation capacity with demographic characteristics on hypertension risk. A total of 512 adult participants (126 hypertension subjects and 386 non-hypertension subjects residing in an arsenic-endemic area in Inner Mongolia, China were included. Urinary levels of inorganic arsenic (iAs, monomethylarsonic acid (MMA, and dimethylarsinic acid (DMA were measured for all subjects. The percentage of urinary arsenic metabolites (iAs%, MMA%, and DMA%, primary methylation index (PMI and secondary methylation index (SMI were calculated to assess arsenic methylation capacity of individuals. Results showed that participants carrying a lower methylation capacity, which is characterized by lower DMA% and SMI, have a higher risk of hypertension compared to their corresponding references after adjusting for multiple confounders. A potential synergy between poor arsenic methylation capacity (higher MMA%, lower DMA% and SMI and older age or higher BMI were detected. The joint effects of higher MMA% and lower SMI with cigarette smoking also suggest some evidence of synergism. The findings of present study indicated that inefficient arsenic methylation capacity was associated with hypertension and the effect might be enhanced by certain demographic factors.

  16. Effect of organic matter amendment, arsenic amendment and water management regime on rice grain arsenic species

    International Nuclear Information System (INIS)

    Norton, Gareth J.; Adomako, Eureka E.; Deacon, Claire M.; Carey, Anne-Marie; Price, Adam H.; Meharg, Andrew A.

    2013-01-01

    Arsenic accumulation in rice grain has been identified as a major problem in some regions of Asia. A study was conducted to investigate the effect of increased organic matter in the soil on the release of arsenic into soil pore water and accumulation of arsenic species within rice grain. It was observed that high concentrations of soil arsenic and organic matter caused a reduction in plant growth and delayed flowering time. Total grain arsenic accumulation was higher in the plants grown in high soil arsenic in combination with high organic matter, with an increase in the percentage of organic arsenic species observed. The results indicate that the application of organic matter should be done with caution in paddy soils which have high soil arsenic, as this may lead to an increase in accumulation of arsenic within rice grains. Results also confirm that flooding conditions substantially increase grain arsenic. -- Highlights: ► High soil arsenic and organic matter caused a reduction in plant growth. ► A delayed flowering time was observed in high arsenic and organic matter soil. ► Total grain arsenic increased in high arsenic and organic matter soil. ► Percentage organic arsenic in the grain altered in arsenic and organic matter soil. -- The addition of high amounts of organic matter to soils led to an increase in total rice grain arsenic, as well as alteration in the percentage arsenic species in the rice grains

  17. Co-inoculation of arbusculr mycorrhizae and nitrogen fixing bacteria enhance alfalfa yield under saline conditions

    International Nuclear Information System (INIS)

    Zhu, R.; Tang, F.; Liu, F.; Chen, J.

    2016-01-01

    The study was to investigate the effects of combined inoculation of Glomus mosseae (arbusculr mycorrhizae fungi, AMF) and Sinorhizobium meliloti (nitrogen-fixing bacteria, i.e., an Rhizobium meliloti, RM) on yield, nutrient contents, nodulation and mycorrhizal colonization of different alfalfa cultivars under saline conditions. An experiment was conducted to test the efficacy of AMF and RM inoculation in development of salt tolerance in alfalfa cultivars (Zhaodong, Nongjing and Longmu) under different salinity levels (0, 60, 120 and 180 mM NaCl). We found that under non stress condition, double inoculation of alfalfa with rhizobium and AM increased the alfalfa yield, nodule weight and number, as well as shoot proline contents, the most when plants were double inoculated followed by AM and rhizobium inoculation, respectively. Whereas under salinity condition, double inoculation of alfalfa with rhizobium and AM increased alfalfa yield, mycorrhizal infection, nodule weight and number as well as increased in shoot proline content, the most followed by AM and rhizobium inoculation, respectively. The Results suggest that growth of alfalfa may be improved by combined inoculation of alfalfa with AM and rhizobium under salt and non-stress conditions. Alleviation of alfalfa growth under saline condition was perhaps due to an increase in mycorrhizal infection and nodule weight and number as well as an increased in shoot proline content by dual inoculation. (author)

  18. Unfolded Protein Response Signaling and MAP Kinase Pathways Underlie Pathogenesis of Arsenic-induced Cutaneous Inflammation

    OpenAIRE

    Li, Changzhao; Xu, Jianmin; Li, Fugui; Chaudhary, Sandeep C.; Weng, Zhiping; Wen, Jianming; Elmets, Craig A.; Ahsan, Habibul; Athar, Mohammad

    2011-01-01

    Arsenic exposure through drinking water is a major global public health problem and is associated with an enhanced risk of various cancers including skin cancer. In human skin, arsenic induces precancerous melanosis and keratosis, which may progress to basal cell and squamous cell carcinoma. However, the mechanism by which these pathophysiological alterations occur remains elusive. In this study, we showed that sub-chronic arsenic exposure to SKH-1 mice induced unfolded protein response (UPR)...

  19. Arsenic tolerant Trichoderma sp. reduces arsenic induced stress in chickpea (Cicer arietinum).

    Science.gov (United States)

    Tripathi, Pratibha; Singh, Poonam C; Mishra, Aradhana; Srivastava, Suchi; Chauhan, Reshu; Awasthi, Surabhi; Mishra, Seema; Dwivedi, Sanjay; Tripathi, Preeti; Kalra, Alok; Tripathi, Rudra D; Nautiyal, Chandra S

    2017-04-01

    Toxic metalloids including arsenic (As) can neither be eliminated nor destroyed from environment; however, they can be converted from toxic to less/non-toxic forms. The form of As species and their concentration determines its toxicity in plants. Therefore, the microbe mediated biotransformation of As is crucial for its plant uptake and toxicity. In the present study the role of As tolerant Trichoderma in modulating As toxicity in chickpea plants was explored. Chickpea plants grown in arsenate spiked soil under green house conditions were inoculated with two plant growth promoting Trichoderma strains, M-35 (As tolerant) and PPLF-28 (As sensitive). Total As concentration in chickpea tissue was comparable in both the Trichoderma treatments, however, differences in levels of organic and inorganic As (iAs) species were observed. The shift in iAs to organic As species ratio in tolerant Trichoderma treatment correlated with enhanced plant growth and nutrient content. Arsenic stress amelioration in tolerant Trichoderma treatment was also evident through rhizospheric microbial community and anatomical studies of the stem morphology. Down regulation of abiotic stress responsive genes (MIPS, PGIP, CGG) in tolerant Trichoderma + As treatment as compared to As alone and sensitive Trichoderma + As treatment also revealed that tolerant strain enhanced the plant's potential to cope with As stress as compared to sensitive one. Considering the bioremediation and plant growth promotion potential, the tolerant Trichoderma may appear promising for its utilization in As affected fields for enhancing agricultural productivity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. DO ELEVATED CO2 AND N FERTILIZATION ALTER FINE ROOT-MYCORRHIZAE RELATIONSHIPS IN PINUS PONDEROSA?

    Science.gov (United States)

    Despite extensive studies on the response of plants to elevated CO2, climate change and N deposition, little is known about the response of roots and mycorrhizae in spite of their key role in plant water and nutrient acquisition. The effects of elevated CO2 and N fertilization on...

  1. Factors Affecting Arsenic Methylation in Arsenic-Exposed Humans: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Shen, Hui; Niu, Qiang; Xu, Mengchuan; Rui, Dongsheng; Xu, Shangzhi; Feng, Gangling; Ding, Yusong; Li, Shugang; Jing, Mingxia

    2016-02-06

    Chronic arsenic exposure is a critical public health issue in many countries. The metabolism of arsenic in vivo is complicated because it can be influenced by many factors. In the present meta-analysis, two researchers independently searched electronic databases, including the Cochrane Library, PubMed, Springer, Embase, and China National Knowledge Infrastructure, to analyze factors influencing arsenic methylation. The concentrations of the following arsenic metabolites increase (piAs), monomethyl arsenic (MMA), dimethyl arsenic (DMA), and total arsenic. Additionally, the percentages of iAs (standard mean difference (SMD): 1.00; 95% confidence interval (CI): 0.60-1.40; p< 0.00001) and MMA (SMD: 0.49; 95% CI: 0.21-0.77; p = 0.0006) also increase, while the percentage of DMA (SMD: -0.57; 95% CI: -0.80--0.31; p< 0.0001), primary methylation index (SMD: -0.57; 95% CI: -0.94--0.20; p = 0.002), and secondary methylation index (SMD: -0.27; 95% CI: -0.46--0.90; p = 0.004) decrease. Smoking, drinking, and older age can reduce arsenic methylation, and arsenic methylation is more efficient in women than in men. The results of this analysis may provide information regarding the role of arsenic oxidative methylation in the arsenic poisoning process.

  2. Environmental Source of Arsenic Exposure

    OpenAIRE

    Chung, Jin-Yong; Yu, Seung-Do; Hong, Young-Seoub

    2014-01-01

    Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a ...

  3. Arbuscular mycorrhiza stimulates biological nitrogen fixation in two Medicago spp. through omproved phosphorus acquisition

    Czech Academy of Sciences Publication Activity Database

    Püschel, David; Janoušková, Martina; Voříšková, Alena; Gryndlerová, H.; Vosátka, Miroslav; Jansa, J.

    2017-01-01

    Roč. 8, MAR 27 (2017), s. 1-12, č. článku no. 390. ISSN 1664-462X R&D Projects: GA ČR GA15-05466S Institutional support: RVO:67985939 Keywords : arbuscular mycorrhiza * biological nitrogen fixation * phosphorus uptake Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 4.298, year: 2016

  4. Plants as Useful Vectors to Reduce Environmental Toxic Arsenic Content

    Directory of Open Access Journals (Sweden)

    Nosheen Mirza

    2014-01-01

    Full Text Available Arsenic (As toxicity in soil and water is an increasing menace around the globe. Its concentration both in soil and environment is due to natural and anthropogenic activities. Rising arsenic concentrations in groundwater is alarming due to the health risks to plants, animals, and human beings. Anthropogenic As contamination of soil may result from mining, milling, and smelting of copper, lead, zinc sulfide ores, hide tanning waste, dyes, chemical weapons, electroplating, gas exhaust, application of municipal sludge on land, combustion of fossil fuels, As additives to livestock feed, coal fly ash, and use of arsenical pesticides in agricultural sector. Phytoremediation can be viewed as biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system that enhances the natural ecosystems for subsequent productive use. The present review presents recent scientific developments regarding phytoremediation of arsenic contaminated environments and its possible detoxification mechanisms in plants.

  5. Plants as Useful Vectors to Reduce Environmental Toxic Arsenic Content

    Science.gov (United States)

    Mirza, Nosheen; Mahmood, Qaisar; Maroof Shah, Mohammad; Pervez, Arshid; Sultan, Sikander

    2014-01-01

    Arsenic (As) toxicity in soil and water is an increasing menace around the globe. Its concentration both in soil and environment is due to natural and anthropogenic activities. Rising arsenic concentrations in groundwater is alarming due to the health risks to plants, animals, and human beings. Anthropogenic As contamination of soil may result from mining, milling, and smelting of copper, lead, zinc sulfide ores, hide tanning waste, dyes, chemical weapons, electroplating, gas exhaust, application of municipal sludge on land, combustion of fossil fuels, As additives to livestock feed, coal fly ash, and use of arsenical pesticides in agricultural sector. Phytoremediation can be viewed as biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system) that enhances the natural ecosystems for subsequent productive use. The present review presents recent scientific developments regarding phytoremediation of arsenic contaminated environments and its possible detoxification mechanisms in plants. PMID:24526924

  6. Correlation of arsenic exposure through drinking groundwater and urinary arsenic excretion among adults in Pakistan.

    Science.gov (United States)

    Ahmed, Mubashir; Fatmi, Zafar; Ali, Arif

    2014-01-01

    Long-term exposure to arsenic has been associated with manifestation of skin lesions (melanosis/keratosis) and increased risk of internal cancers (lung/bladder). The objective of the study described here was to determine the relationship between exposure of arsenic through drinking groundwater and urinary arsenic excretion among adults > or =15 years of age living in Khairpur district, Pakistan. Total arsenic was determined in drinking groundwater and in spot urine samples of 465 randomly selected individuals through hydride generation-atomic absorption spectrometry. Spearman's rank correlation coefficient was calculated between arsenic in drinking groundwater and arsenic excreted in urine. The median arsenic concentration in drinking water was 2.1 microg/L (range: 0.1-350), and in urine was 28.5 microg/L (range: 0.1-848). Positive correlation was found between total arsenic in drinking water and in urine (r = .52, p arsenic may be used as a biomarker of arsenic exposure through drinking water.

  7. Urinary Arsenic Metabolites of Subjects Exposed to Elevated Arsenic Present in Coal in Shaanxi Province, China

    Directory of Open Access Journals (Sweden)

    Linsheng Yang

    2011-06-01

    Full Text Available In contrast to arsenic (As poisoning caused by naturally occurring inorganic arsenic-contaminated water consumption, coal arsenic poisoning (CAP induced by elevated arsenic exposure from coal combustion has rarely been reported. In this study, the concentrations and distributions of urinary arsenic metabolites in 57 volunteers (36 subjects with skin lesions and 21 subjects without skin lesions, who had been exposed to elevated levels of arsenic present in coal in Changshapu village in the south of Shaanxi Province (China, were reported. The urinary arsenic species, including inorganic arsenic (iAs [arsenite (iAsIII and arsenate (iAsV], monomethylarsonic acid (MMAV and dimethylarsinic acid (DMAV, were determined by high-performance liquid chromatography (HPLC combined with inductively coupled plasma mass spectroscopy (ICP-MS. The relative distributions of arsenic species, the primary methylation index (PMI = MMAV/iAs and the secondary methylation index (SMI = DMAV/MMAV were calculated to assess the metabolism of arsenic. Subjects with skin lesions had a higher concentration of urinary arsenic and a lower arsenic methylation capability than subjects without skin lesions. Women had a significantly higher methylation capability of arsenic than men, as defined by a higher percent DMAV and SMI in urine among women, which was the one possible interpretation of women with a higher concentration of urinary arsenic but lower susceptibility to skin lesions. The findings suggested that not only the dose of arsenic exposure but also the arsenic methylation capability have an impact on the individual susceptibility to skin lesions induced by coal arsenic exposure.

  8. Availability of caesium radionuclides to plants - classification of soils and role of mycorrhiza

    Energy Technology Data Exchange (ETDEWEB)

    Drissner, J.; Buermann, W.; Enslin, F.; Heider, R.; Klemt, E.; Miller, R.; Schick, G.; Zibold, G. [Fachhochschule Ravensburg-Weingarten, D-88241 Weingarten (Germany)

    1998-10-01

    At different locations in spruce stands spread rather homogeneously over southern Baden-Wuerttemberg, samples of soil and plants were taken and the vertical distribution of the caesium radionuclides in the soil was studied. As a direct measure of the bioavailability, the aggregated transfer factor, T{sub ag}, was determined for fern, bilberry, raspberry, blackberry, and clover. The T{sub ag} (in m2 kg{sup -1}) is defined by the specific caesium activity (in Bq kg{sup -1}) of the dry mass of the plants, divided by the total inventory (in Bq m{sup -2}) of the soil. It varies between 0{center_dot}5 and 0{center_dot}001 m2kg{sup -1}, being highest for fern and lowest for blackberry or clover at all sampling sites. Most decisive for the value of the T{sub ag} are kind of humus deposit, thickness and pH value of the humus layers. Also important are the soil properties, whereas geology has only a minor influence on T{sub ag}. At different sampling sites in spruce forests, the T{sub ag} can vary by two orders of magnitude for one plant species. Caesium desorption experiments were performed. We could not find a dependence of the transfer of caesium to the plant on the desorbability of caesium from the soil, which implies a more complex transport mechanism than simple ion exchange in the soil solution. It is suggested that the transport of caesium is mediated by mycorrhiza fungi. Therefore, we studied the density of mycorrhiza hyphae in the O{sub f}, O{sub h} and A{sub h} soil horizons of two sites differing in T{sub ag} by a factor of 10. The densities of mycorrhiza hyphae in the O{sub h} and A{sub h} soil horizons each differ by a factor of 2 for the two sites. Yet, the effect of the hyphae density on radiocaesium uptake has to be a subject of further investigation. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  9. Distribution of arsenic in groundwater in the area of Chalkidiki, Northern Greece

    International Nuclear Information System (INIS)

    Kouras, A.; Katsoyiannis, I.; Voutsa, D.

    2007-01-01

    An integrate study aiming at the occurrence and distribution of arsenic in groundwater in the area of Chalkidiki, Northern Greece has been carried out. Groundwater samples from public water supply wells and private wells were analysed for arsenic and other quality parameters (T, pH, EC, Ca, Mg, Na, K, Cl, HCO 3 , NO 3 , SO 4 , B, Fe, Mn). Arsenic showed high spatial variation; ranged from 0.001 to 1.840 mg/L. Almost 65% of the examined groundwaters exhibit arsenic concentrations higher than the maximum concentration limit of 0.010 mg/L, proposed for water intended for human consumption. Correlation analysis and principal component analysis were employed to find out possible relationships among the examined parameters and groundwater samples. Arsenic is highly correlated with potassium, boron, bicarbonate, sodium, manganese and iron suggesting common geogenic origin of these elements and conditions that enhance their mobility. Three groups of groundwater with different physicochemical characteristics were found in the study area: (a) groundwater with extremely high arsenic concentrations (1.6-1.9 mg/L) and high temperature (33-42 deg. C) from geothermal wells, (b) groundwater with relatively high arsenic concentrations (>0.050 mg/L), lower temperatures and relatively high concentrations of major ions, iron and manganese and, (c) groundwater with low arsenic concentrations that fulfil the proposed limits for dinking water

  10. Effects of vesicular-arbuscular mycorrhizae on survival and growth of perennial grasses in lignite overburden in Texas

    Energy Technology Data Exchange (ETDEWEB)

    Call, C.A.; Davies, F.T.

    1988-12-01

    Seedlings of sideoats grama (Bouteloua curtipendula), Indiangrass (Sorghastrum nutans), and kleingrass (Panicum coloratum) were inoculated with vesicular-arbuscular mycorrhizal (VAM) fungi (Glomus fasciculatum and Gigaspora margarita) in a containerized system and transplanted into lignite overburden in the Post Oak Savannah region of Texas, U.S.A. After three growing seasons without cultural inputs, plants inoculated with VAM fungi had greater survival percentages, basal diameters, and above-ground biomass than noninoculated plants. Inoculated plants had higher levels of nitrogen and phosphorus in above-ground biomass than noninoculated plants. Root colonization percentages of inoculated plants remained fairly stable while noninoculated plants showed low levels of colonization over the 3-year study period. Vesicular-arbuscular mycorrhizae enhanced the survival and growth of the 3 grass species by making effective use of limited resources in the lignite overburden. 31 refs., 3 tabs.

  11. Arsenic activation analysis of freshwater fish through the precipitation of elemental arsenic

    International Nuclear Information System (INIS)

    Comparetto, G.M.; Jester, W.A.; Skinner, W.F.

    1982-01-01

    The activation analysis of trace elements of arsenic in biological samples is complicated by the interference of a 82 Br photo peak (554KeV) and the compton continuum with the major 76 As photo peak of 559 KeV. In addition, the half-lives of 24 Na, 82 Br, and 76 As are too similar to be resolved by varying irradiation and/or decay times. Thus post irradiation chemical separation of arsenic is often required. A study of existing radiochemistry techniques reported in the literature found that existing methods were complex x and/or lengthy. In this work, a more rapid and less extensive method was required to analyze a large number of fish samples exposed to fly ash sluice water from coalburning power plant. A method has been developed which involves the dissolution of irradiated homogenized fish samples, the addition of an arsenic carrier, and the reduction of arsenic to the +3 state. Arsenic is then precipitated as elemental arsenic. An important factor in this work was the discovery that this procedure produced arsenic yields of 81+-3% for both the fish samples and the NBC Orchard leaves standard employed in this analysis. Thus the determination of absolute arsenic yields is not required. This method has been used to analyze 32 of the fish samples the average arsenic content of which was found to vary between 0.08 and 4.8 ppm. (author)

  12. Arsenic species excretion after dimercaptopropanesulfonic acid (DMPS) treatment of an acute arsenic trioxide poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Heinrich-Ramm, R. [Ordinariat fuer Arbeitsmedizin der Universitaet Hamburg und Zentralinstitut fuer Arbeitsmedizin, Hamburg (Germany); Schaller, K.H.; Angerer, J. [Institut und Poliklinik fuer Arbeits-, Sozial- und Umweltmedizin der Universitaet Erlangen-Nuernberg, Schillerstr. 25, 91054 Erlangen (Germany); Horn, J. [Medizinische Klinik II, Toxikologische-internistische Intensivstation, Klinikum Nuernberg, Nuernberg (Germany)

    2003-02-01

    We studied the urinary excretion of the different arsenic species in urine samples from a young man who tried to commit suicide by ingesting about 0.6 g arsenic trioxide. He received immediate therapy with dimercaptopropanesulfonic acid (DMPS) after his delivery into the hospital. We assessed urinary arsenite (inorganic trivalent arsenic), arsenate (inorganic pentavalent arsenic), pentavalent dimethylarsinic acid (DMA) and pentavalent monomethylarsonic acid (MMA) in urine with ion-exchange chromatography and on-line hydride-technique atomic absorption spectrometry. The predominant amount of the excreted arsenic was unchanged trivalent inorganic arsenic (37.4%), followed by pentavalent inorganic arsenic (2.6%), MMA (2.1%), DMA (0.2%) and one unidentified arsenic species (0.7%, if calculated as DMA). In the first urine voiding in the clinic, the total arsenic concentration was 215 mg/l, which fell 1000-fold after 8 days of DMPS therapy. A most striking finding was the almost complete inhibition of the second methylation step in arsenic metabolism. As mechanisms for the reduced methylation efficiency, the saturation of the enzymatic process of arsenic methylation, the high dosage of antidote DMPS, which might inhibit the activity of the methyl transferases, and analytical reasons are discussed. The high dosage of DMPS is the most likely explanation. The patient left the hospital after a 12-day treatment with antidote. (orig.)

  13. Arsenic waste management: a critical review of testing and disposal of arsenic-bearing solid wastes generated during arsenic removal from drinking water.

    Science.gov (United States)

    Clancy, Tara M; Hayes, Kim F; Raskin, Lutgarde

    2013-10-01

    Water treatment technologies for arsenic removal from groundwater have been extensively studied due to widespread arsenic contamination of drinking water sources. Central to the successful application of arsenic water treatment systems is the consideration of appropriate disposal methods for arsenic-bearing wastes generated during treatment. However, specific recommendations for arsenic waste disposal are often lacking or mentioned as an area for future research and the proper disposal and stabilization of arsenic-bearing waste remains a barrier to the successful implementation of arsenic removal technologies. This review summarizes current disposal options for arsenic-bearing wastes, including landfilling, stabilization, cow dung mixing, passive aeration, pond disposal, and soil disposal. The findings from studies that simulate these disposal conditions are included and compared to results from shorter, regulatory tests. In many instances, short-term leaching tests do not adequately address the range of conditions encountered in disposal environments. Future research directions are highlighted and include establishing regulatory test conditions that align with actual disposal conditions and evaluating nonlandfill disposal options for developing countries.

  14. Arsenic accumulation by two brake ferns growing on an arsenic mine and their potential in phytoremediation.

    Science.gov (United States)

    Wei, Chao-Yang; Chen, Tong-Bin

    2006-05-01

    In an area near an arsenic mine in Hunan Province of south China, soils were often found with elevated arsenic levels. A field survey was conducted to determine arsenic accumulation in 8 Cretan brake ferns (Pteris cretica) and 16 Chinese brake ferns (Pteris vittata) growing on these soils. Three factors were evaluated: arsenic concentration in above ground parts (fronds), arsenic bioaccumulation factor (BF; ratio of arsenic in fronds to soil) and arsenic translocation factor (TF; ratio of arsenic in fronds to roots). Arsenic concentrations in the fronds of Chinese brake fern were 3-704 mg kg-1, the BFs were 0.06-7.43 and the TFs were 0.17-3.98, while those in Cretan brake fern were 149-694 mg kg-1, 1.34-6.62 and 1.00-2.61, respectively. Our survey showed that both ferns were capable of arsenic accumulation under field conditions. With most of the arsenic being accumulated in the fronds, these ferns have potential for use in phytoremediation of arsenic contaminated soils.

  15. The Role of Mycorrhiza in Drought Tolerance of Marigold (Calendula officinalis L.

    Directory of Open Access Journals (Sweden)

    Sh. Moghadasan

    2016-01-01

    Full Text Available To study the effect of mycorrhizal symbiosis and drought stress on marigold, a factorial experiment in a completely randomized design with three replications was conducted at the Plant Research Laboratory of Islamic Azad University, Neyshabur branch in 2014. The first factor consisted of application and non-application of mycorrhiza (Glomus intraradices and the second factor consisted of drought stress with three levels (irrigation based on 100%, 75% and 50% of field capacity. The results showed that growth parameters like plant height, leaf number, leaf area, root, shoot dry/fresh weight, Chla and Chlb content were significantly decreased by drought stress in both mycorrhizal and non-mycorrhizal plants. However, inoculation of plants by mycorrhizal fungus increased growth parameters and photosynthetic pigments as compared with non-mycorrhizal ones. Traits like RWC, potassium and phosphorus in response to drought stress were decreased. Inoculation of plant roots with Mycorrhizal fungi increased significantly RWC, potassium and phosphorus content of the plants under drought conditions as compared with non-inoculated plants. The results also showed the mycorrhizal symbiosis by Glomus intraradices improved drought tolerance of marigold through enhancing the absorption of water and mineral ions.

  16. Arsenic Methyltransferase

    Science.gov (United States)

    The metalloid arsenic enters the environment by natural processes (volcanic activity, weathering of rocks) and by human activity (mining, smelting, herbicides and pesticides). Although arsenic has been exploited for homicidal and suicidal purposes since antiquity, its significan...

  17. Arsenic-Induced Genotoxicity and Genetic Susceptibility to Arsenic-Related Pathologies

    Directory of Open Access Journals (Sweden)

    Fabrizio Bianchi

    2013-04-01

    Full Text Available The arsenic (As exposure represents an important problem in many parts of the World. Indeed, it is estimated that over 100 million individuals are exposed to arsenic, mainly through a contamination of groundwaters. Chronic exposure to As is associated with adverse effects on human health such as cancers, cardiovascular diseases, neurological diseases and the rate of morbidity and mortality in populations exposed is alarming. The purpose of this review is to summarize the genotoxic effects of As in the cells as well as to discuss the importance of signaling and repair of arsenic-induced DNA damage. The current knowledge of specific polymorphisms in candidate genes that confer susceptibility to arsenic exposure is also reviewed. We also discuss the perspectives offered by the determination of biological markers of early effect on health, incorporating genetic polymorphisms, with biomarkers for exposure to better evaluate exposure-response clinical relationships as well as to develop novel preventative strategies for arsenic- health effects.

  18. Reaction Mechanism and Distribution Behavior of Arsenic in the Bottom Blown Copper Smelting Process

    Directory of Open Access Journals (Sweden)

    Qinmeng Wang

    2017-08-01

    Full Text Available The control of arsenic, a toxic and carcinogenic element, is an important issue for all copper smelters. In this work, the reaction mechanism and distribution behavior of arsenic in the bottom blown copper smelting process (SKS process were investigated and compared to the flash smelting process. There are obvious differences of arsenic distribution in the SKS process and flash process, resulting from the differences of oxygen potentials, volatilizations, smelting temperatures, reaction intensities, and mass transfer processes. Under stable production conditions, the distributions of arsenic among matte, slag, and gas phases are 6%, 12%, and 82%, respectively. Less arsenic is reported in the gas phase with the flash process than with the SKS process. The main arsenic species in gas phase are AsS (g, AsO (g, and As2 (g. Arsenic exists in the slag predominantly as As2O3 (l, and in matte as As (l. High matte grade is harmful to the elimination of arsenic to gas. The changing of Fe/SiO2 has slight effects on the distributions of arsenic. In order to enhance the removal of arsenic from the SKS smelting system to the gas phase, low oxygen concentration, low ratios of oxygen/ore, and low matte grade should be chosen. In the SKS smelting process, no dust is recycled, and almost all dust is collected and further treated to eliminate arsenic and recover valuable metals by other process streams.

  19. Arbuscular Mycorrhiza Stimulates Biological Nitrogen Fixation in Two Medicago spp. through Improved Phosphorus Acquisition

    Czech Academy of Sciences Publication Activity Database

    Püschel, David; Janoušková, M.; Voříšková, A.; Gryndlerová, Hana; Vosátka, M.; Jansa, Jan

    2017-01-01

    Roč. 8, MAR 27 (2017), s. 1-12, č. článku 390. ISSN 1664-462X R&D Projects: GA ČR GA15-05466S; GA MŠk(CZ) LK11224 Institutional support: RVO:61388971 Keywords : arbuscular mycorrhiza * nitrogen acquisition * phosphorus uptake Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 4.298, year: 2016

  20. The Arsenic crisis in Bangladesh (Invited)

    Science.gov (United States)

    Harvey, C.; Ashfaque, K.; Neumann, R. B.; Badruzzaman, B.; Ali, A.

    2010-12-01

    The Ganges Delta suffers from water-borne disease. Arsenic in the groundwater pumped from drinking water wells is causing severe and widespread disease, and these wells were installed, in part, to avoid pathogens in the surface water supply. I will discuss the hydrogeologic controls of arsenic concentrations in groundwater, specifically the role of enhanced groundwater circulation driven by irrigation pumping and the effects of the solute loads transported into aquifers with recharge through different surface features, such as rice fields, rivers, and ponds. I will contrast the approaches taken in Southeast Asia for studying groundwater contamination with methods used in the U.S. I will compare findings from several sites in the region and consider how improved models of the coupled hydrologic and biogeochemical system can be used to provide safer water.

  1. Changes in Nutrient Content of Root and Grain of Wheat Cultivars Inoculated by Azospirillum and Mycorrhiza

    Directory of Open Access Journals (Sweden)

    M. Jiriaie

    2016-02-01

    Full Text Available Introduction: Providing the nutritional requirements of agricultural crops by non-chemical resources is a new approach in the organic farming that has attracted the attention of both the researchers and the consumers in recent years. Therefore, it is highly important to find new fertilizer resources that are both economically able to provide the nutritional needs of the crop plants and have no adverse effects on the consumers and the environment. Materials and Methods: With this approach, an experiment was conducted in the research station of Shahid Chamran University of Ahvaz, Iran in 2012-13. The experimental design was factorial based on randomized complete blocks design with three replications. The treatments including Mycorrhizal fungi in three levels (i.e. no use of strain; use of Glomus intraradices strain; and use of Glomus mosseae strain, bacteria Azospirillum lipoferum in two-levels (i.e. non-inoculated and inoculated and wheat cultivars in three levels (i.e. Chamran; Dena; and Behrang. The measured parameters include the concentration of macronutrients (i.e. nitrogen, phosphorus and potassium and some micronutrients (i.e. zinc, iron and manganese in two part seed and the root of wheat. Results and Discussion: Surveying the elements content in the root and the grain indicated a significant and positive effect of the use the Azospirillum and Mycorrhiza to improve the concentration of the elements in wheat cultivars. However, the simultaneous use of these microorganisms led to an increase of the effects of their application on their assessed traits.Finally the highest concentration of N (2.21 present, P (0.50 present and Fe (33.88 mg.kg-1 were observed in the grain; the highest concentration of K (0.93 present and 0.54 present and Mn (43.11 and 23.63 mg.kg-1 were observed in the grain and root, respectively. Moreover, the highest concentration of Zn in the root (19.70 mg.kg-1 was obtained from inoculation of C.V Dena seeds with

  2. Changes in host-mycorrhiza relationships revealed by stable isotopes after naturally-induced thinning of the stand: case study on Tuber aestivum.

    Science.gov (United States)

    Gavrichkova, Olga; Lauteri, Marco; Ciolfi, Marco; Chiocchini, Francesca; Paris, Pierluigi; Pisanelli, Andrea; Portarena, Silvia; Brugnoli, Enrico

    2016-04-01

    Terrestrial plants overcome nutrients and water limitations by forming mutualistic associations with mycorrhizal fungi. Fungi, in return, take advantage from the carbohydrates supplied by the host. Some mycorrhizal fruit bodies, like that of Tuber spp., have a peculiar gastronomic value with many efforts being undertaken to predict and enhance their productivity. However, many issues of truffle-producing mycorrhizal ecology are still poorly understood, in particular optimal conditions favoring fruit formation, potential host plants and host-mycorrhiza relationships. In this study, we tested the applicability of stable isotope measurements under natural abundance to identify the plants which likely host the mycorrhiza of Tuber aestivum and to characterize host-mycorrhizal nutrient, water and carbohydrate exchange under plant natural growing conditions and with the change of the forest cover after naturally occurred thinning. For these purposes, sampling of the fruit bodies of T. aestivum was performed during the growing season 2011 in a mixed broadleaved-coniferous forest in central Italy (initially the site was a manmade pine plantation). Nine truffle-producing parcels were identified with five being composed of the original Pinus pinaster -dominated vegetation and four in which pine was replaced by broadleaf species after both wind-induced thinning and natural dieback of pine trees. Seasonal variation of δ13C, δ15N and δ18O were analyzed in the fungal material, in the surrounding soil and in the plant material of the potential host species (xylem water in the trunk, branches and leaves, recently assimilated carbohydrates in phloem and leaves). The results showed a possibility of the identification of the mycorrhizal host species applying isotope analyses, with mycorrhiza receiving most part of the carbohydrates from the pine in pine-dominated parcels. Interestingly, in thinned parcels, the truffle bodies maintained isotope composition similar to bodies gathered

  3. Environmental source of arsenic exposure.

    Science.gov (United States)

    Chung, Jin-Yong; Yu, Seung-Do; Hong, Young-Seoub

    2014-09-01

    Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.

  4. Environmental Source of Arsenic Exposure

    Directory of Open Access Journals (Sweden)

    Jin-Yong Chung

    2014-09-01

    Full Text Available Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.

  5. Lime and phosphate application as mycorrhizae stimulation to enhance growth and yield of Marandu grass

    Directory of Open Access Journals (Sweden)

    Franklin Eduardo Melo Santiago

    2017-08-01

    Full Text Available Pastures are important food sources for Brazilian cattle herds. However, inadequate management of soil fertility has emerged as a major cause of low yield rates and of progressive degradation of these areas. The objective of the present study was to evaluate growth, by means of morphogenetic and structural characteristics, and yield of Brachiaria brizantha Stapf. cv. Marandu as functions of the application of the mycorrhizae stimulant formononetin, associated with lime and phosphate application. The experimental design was completely randomised with four replications, and the treatments were arranged in a 2 x 2 x 5 factorial scheme, consisting of two liming treatments (with and without limestone, two formononetin treatments (with and without application and five P2O5 doses (0, 25, 50, 100 and 200 mg dm-3. Three shoot cuttings were carried out after a first standardisation cutting to evaluate the morphogenetic and structural characteristics as well as the dry matter yield of different morphological fractions. Liming and phosphate application at the dose of 141 mg dm-3 P2O5 increased growth and yield of Marandu grass, and these practices are essential for the cultivation of this pasture grass in Yellow Latosol of the Cerrado region of Piauí, Brazil. The application of formononetin increased stem elongation rate, total number of tillers and green stem dry matter, and decreased dead dry matter of Marandu grass, which are effects that contribute to the improvement of pasture quality.

  6. Uptake and specification of selenium in garlic cultivated in soil amended with symbiotic fungi (mycorrhiza) and selenate

    NARCIS (Netherlands)

    Larsen, E.H.; Lobinski, R.; Burger-Meijer, K.; Hansen, M.; Ruzik, R.; Mazurowska, L.; Rasmussen, P.H.; Sloth, J.J.; Scholten, O.E.; Kik, C.

    2006-01-01

    The scope of the work was to investigate the influence of selenate fertilisation and the addition of symbiotic fungi (mycorrhiza) to soil on selenium and selenium species concentrations in garlic. The selenium species were extracted from garlic cultivated in experimental plots by proteolytic

  7. Urinary arsenic profile affects the risk of urothelial carcinoma even at low arsenic exposure

    International Nuclear Information System (INIS)

    Pu, Y.-S.; Yang, S.-M.; Huang, Y.-K.; Chung, C.-J.; Huang, Steven K.; Chiu, Allen Wen-Hsiang; Yang, M.-H.; Chen, C.-J.; Hsueh, Y.-M.

    2007-01-01

    Arsenic exposure is associated with an increased risk of urothelial carcinoma (UC). To explore the association between individual risk and urinary arsenic profile in subjects without evident exposure, 177 UC cases and 313 age-matched controls were recruited between September 2002 and May 2004 for a case-control study. Urinary arsenic species including the following three categories, inorganic arsenic (As III + As V ), monomethylarsonic acid (MMA V ) and dimethylarsinic acid (DMA V ), were determined with high-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. Arsenic methylation profile was assessed by percentages of various arsenic species in the sum of the three categories measured. The primary methylation index (PMI) was defined as the ratio between MMA V and inorganic arsenic. Secondary methylation index (SMI) was determined as the ratio between DMA V and MMA V . Smoking is associated with a significant risk of UC in a dose-dependent manner. After multivariate adjustment, UC cases had a significantly higher sum of all the urinary species measured, higher percent MMA V , lower percent DMA V , higher PMI and lower SMI values compared with controls. Smoking interacts with the urinary arsenic profile in modifying the UC risk. Differential carcinogenic effects of the urinary arsenic profile, however, were seen more prominently in non-smokers than in smokers, suggesting that smoking is not the only major environmental source of arsenic contamination since the UC risk differs in non-smokers. Subjects who have an unfavorable urinary arsenic profile have an increased UC risk even at low exposure levels

  8. Arsenic in the human food chain, biotransformation and toxicology--Review focusing on seafood arsenic.

    Science.gov (United States)

    Molin, Marianne; Ulven, Stine Marie; Meltzer, Helle Margrete; Alexander, Jan

    2015-01-01

    Fish and seafood are main contributors of arsenic (As) in the diet. The dominating arsenical is the organoarsenical arsenobetaine (AB), found particularly in finfish. Algae, blue mussels and other filter feeders contain less AB, but more arsenosugars and relatively more inorganic arsenic (iAs), whereas fatty fish contain more arsenolipids. Other compounds present in smaller amounts in seafood include trimethylarsine oxide (TMAO), trimethylarsoniopropionate (TMAP), dimethylarsenate (DMA), methylarsenate (MA) and sulfur-containing arsenicals. The toxic and carcinogenic arsenical iAs is biotransformed in humans and excreted in urine as the carcinogens dimethylarsinate (DMA) and methylarsonate (MA), producing reactive intermediates in the process. Less is known about the biotransformation of organoarsenicals, but new insight indicates that bioconversion of arsenosugars and arsenolipids in seafood results in urinary excretion of DMA, possibly also producing reactive trivalent arsenic intermediates. Recent findings also indicate that the pre-systematic metabolism by colon microbiota play an important role for human metabolism of arsenicals. Processing of seafood may also result in transformation of arsenicals. Copyright © 2015 Elsevier GmbH. All rights reserved.

  9. ARSENIC SPECIATION ANALYSIS IN HUMAN SALIVA

    Science.gov (United States)

    Background: Determination of arsenic species in human saliva is potentially useful for biomonitoring of human exposure to arsenic and for studying arsenic metabolism. However, there is no report on the speciation analysis of arsenic in saliva. Methods: Arsenic species in saliva ...

  10. The effect of nanocrystalline magnetite size on arsenic removal

    Directory of Open Access Journals (Sweden)

    J.T. Mayo et al

    2007-01-01

    Full Text Available Higher environmental standards have made the removal of arsenic from water an important problem for environmental engineering. Iron oxide is a particularly interesting sorbent to consider for this application. Its magnetic properties allow relatively routine dispersal and recovery of the adsorbent into and from groundwater or industrial processing facilities; in addition, iron oxide has strong and specific interactions with both As(III and As(V. Finally, this material can be produced with nanoscale dimensions, which enhance both its capacity and removal. The objective of this study is to evaluate the potential arsenic adsorption by nanoscale iron oxides, specifically magnetite (Fe3O4 nanoparticles. We focus on the effect of Fe3O4 particle size on the adsorption and desorption behavior of As(III and As(V. The results show that the nanoparticle size has a dramatic effect on the adsorption and desorption of arsenic. As particle size is decreased from 300 to 12 nm the adsorption capacities for both As(III and As(V increase nearly 200 times. Interestingly, such an increase is more than expected from simple considerations of surface area and suggests that nanoscale iron oxide materials sorb arsenic through different means than bulk systems. The desorption process, however, exhibits some hysteresis with the effect becoming more pronounced with small nanoparticles. This hysteresis most likely results from a higher arsenic affinity for Fe3O4 nanoparticles. This work suggests that Fe3O4 nanocrystals and magnetic separations offer a promising method for arsenic removal.

  11. Arsenic speciation in Chinese Herbal Medicines and human health implication for inorganic arsenic

    International Nuclear Information System (INIS)

    Liu Xiaojuan; Zhao Quanli; Sun Guoxin; Williams, Paul; Lu Xiujun; Cai Jingzhu; Liu Wenju

    2013-01-01

    Rice and drinking water are recognized as the dominant sources of arsenic (As) for human intake, while little is known about As accumulation and speciation in Chinese Herbal Medicines (CHMs), which have been available for many hundreds of years for the treatment of diseases in both eastern and western cultures. Inorganic arsenic was the predominant species in all of CHMs samples. The levels of inorganic arsenic in CHMs from fields and markets or pharmacies ranged from 63 to 550 ng/g with a mean of 208 ng/g and 94 to 8683 ng/g with a mean of 1092 ng/g, respectively. The highest concentration was found in the Chrysanthemum from pharmacies. It indicates that the risk of inorganic As in CHMs to human health is higher in medicines from markets or pharmacies than that collected directly from fields. Some CHMs may make a considerable contribution to the human intake of inorganic arsenic. - Highlights: ► Arsenic speciation was extracted using 1% HNO 3 in microwave. ► Inorganic arsenic was the predominant species in all of CHMs samples. ► The highest concentration of inorganic arsenic was found in the Chrysanthemum. - Inorganic arsenic was the predominant species in all of CHMs samples.

  12. Arsenic adsorption of lateritic soil, limestone powder, lime and fly ash on arsenic-contaminated soil

    Directory of Open Access Journals (Sweden)

    Wuthiphun, L.

    2007-05-01

    Full Text Available Arsenic adsorption efficiency of soil covering materials (lateritic soil, limestone powder, lime and fly ash on arsenic-contaminated soil obtained from Ronpiboon District, Nakhon Sri Thammarat Province tosolve arsenic air pollution problem was investigated using batch experiments. The four types of the aforementioned soil covering materials were examined to determine their arsenic adsorption efficiency, equilibriumtime as well as adsorption isotherms.The results revealed that among soil covering materials mixed with arsenic-contaminated soil at 10% w/w, the efficiency of arsenic adsorption of fly ash, lateritic soil, lime and limestone powder were 84, 60,38 and 1% respectively. The equilibrium time for lateritic soil at pH 4 was achieved within 4 hrs, whereas pH 7 and 12, the equilibrium time was 6 hrs. For fly ash, 2 hrs were required to reach the equilibrium at pH 12, while the equilibrium time was attained within 6 hrs at pH 4 and 7. Furthermore, lateritic soil possessedhigh arsenic adsorption efficiency at pH 7 and 4 and best fit with the Langmuir isotherm. The fly ash showing high arsenic adsorption efficiency at pH 12 and 7 fit the Freundlich isotherm at pH 12 and Langmuirisotherm at pH 7.This indicated that lateritic soil was suitable for arsenic adsorption at low pH, whilst at high pH,arsenic was well adsorbed by fly ash. The Freundlich and Langmuir isotherm could be used to determine quantities of soil covering materials for arsenic adsorption to prevent arsenic air pollution from arseniccontaminated soils.

  13. Arsenic and Fluoride Mobilization Mechanism in Groundwater of Indus Delta and Thar Desert, Sindh, Pakistan

    Directory of Open Access Journals (Sweden)

    VIQAR HUSAIN

    2012-06-01

    Full Text Available Indus deltaic plain consists of medium to fine grained sediments, rich in organic matter deposited during the Holocene period. Thar desert is covered with sand dunes and loess originated from transported sediments from Rann of Kutch or the Indus plain by monsoon winds or by the reworking of local alluvial deposits. Groundwater salinity and microbial pollution are common in both types of lanforms, but arsenic (AS and fluoride (F toxicity dominate in the groundwater of Indus delta and Thar desert, respectively. Arsenic concentration in Tando Mohammad Khan and Tando Allayar varies from 10-500 ppb and exhibits near neutral slightly alkaline pH ranging from 6.8 to 8.0. Arsenic distribution is patchy and seems to be related to the prsence of small scale redox zonation in the aquifer. High arsenic affected areas are densely populated and intensively cultivated and its hot spots are those from where the Indus river passed during the Holocene period including Tando Allayar and Tando Mohammad Khan. Extensive ground water irrigation has accelerated flow of groundwater that brought dissolved degraded organic matter in contact with arsenic bearing sediments, enhancing reduction processes and triggering release of arsenic from detrital bioitite and muscovite in the groundwater. Furthermore, unlined sanitation and microbial contamination contribute to degradation of organic matter that enhances the reduction of iron oxy-hydroxide leading to release of arsenic to groundwater. Fluoride is found in all the groundwater samples of Tharparkar district, in the range of 0.96-2.74mg/l. The pH of groundwater is alkaline (7.38-8.59, which is accelerating maximum (1.24%F dissolution in the groundwater. The favourable pH of groundwater and soil composition of Holocene sediments of Indus delta and slightly older alluvium of Thar desert, respectively are responsible for mobilization of arsenic and fluoride in groundwater of Sindh province of Pakistan.

  14. [Study on the variation of arsenic concentration in groundwater and chemical characteristics of arsenic in sediment cores at the areas with endemic arsenic poison disease in Jianghan Plain].

    Science.gov (United States)

    Zhou, Suhua; Ye, Hengpeng; Li, Mingjian; Xiong, Peisheng; Du, Dongyun; Wang, Jingwen

    2015-06-01

    To understand the variation of arsenic concentration in underground water at the endemic arsenic poison disease area of Jianghan Plain so as to better understand the spatial distribution of high arsenic groundwater, hydro-chemical evolution and source of arsenic in this region. Thirty underground water samples were collected respectively around 3 km radius of the two houses where arsenic poisoning patients lived, in Xiantao and Honghu. Sediment cores of three drillings were collected as well. Both paired t-test or paired Wilcoxon Signed Ranking Test were used to compare the arsenic concentration of water. The arsenic concentration in 2011-2012 appeared lower than that in 2006-2007 at the Nanhong village of Xiantao (t = 4.645 3, P arsenic concentration and Cl, HCO3(-), Fe, Mn. However, negative correlations were found between As and SO4(2-), NO3(-). The range of arsenic content in the sediment was 1.500 mg/kg to 17.289 mg/kg. The maximum arsenic content existed in the soil layer, while the minimum arsenic content existed in the sand layer. The concentration of arsenic varied widely with time and space at endemic arsenic poison disease area of Jianghan Plain. Characteristics of these water chemicals showed significant differences, when compared to the groundwater from Datong Basin, Shanxi Shanyin and Hetao Plain of Inner Mongolia, which presented a typical environment with high arsenic contents in the groundwater. The arsenic content in the sediment samples seemed related to the lithologic structure.

  15. Environmental biochemistry of arsenic

    Energy Technology Data Exchange (ETDEWEB)

    Tamaki, S.; Frankenberger, W.T. Jr. (Department of Soil and Environmental Sciences, University of California, Riverside (United States))

    1992-01-01

    Microorganisms are involved in the redistribution and global cycling of arsenic. Arsenic can accumulate and can be subject to various biotransformations including reduction, oxidation, and methylation. Bacterial methylation of inorganic arsenic is coupled to the methane biosynthetic pathway in methanogenic bacteria under anaerobic conditions and may be a mechanism for arsenic detoxification. The pathway proceeds by reduction of arsenate to arsenite followed by methylation to dimethylarsine. Fungi are also able to transform inorganic and organic arsenic compounds into volatile methylarsines. The pathway proceeds aerobically by arsenate reduction to arsenite followed by several methylation steps producing trimethylarsine. Volatile arsine gases are very toxic to mammals because they destroy red blood cells (LD50 in rats; 3.0 mg kg-1). Further studies are needed on dimethylarsine and trimethylarsine toxicity tests through inhalation of target animals. Marine algae transform arsenate into non-volatile methylated arsenic compounds (methanearsonic and dimethylarsinic acids) in seawater. This is considered to be a beneficial step not only to the primary producers, but also to the higher trophic levels, since non-volatile methylated arsenic is much less toxic to marine invertebrates. Freshwater algae like marine algae synthesize lipid-soluble arsenic compounds and do not produce volatile methylarsines. Aquatic plants also synthesize similar lipid-soluble arsenic compounds. In terrestrial plants, arsenate is preferentially taken up 3 to 4 times the rate of arsenite. In the presence of phosphate, arsenate uptake is inhibited while in the presence of arsenate, phosphate uptake is only slightly inhibited. There is a competitive interaction between arsenate and phosphate for the same uptake system in terrestrial plants.

  16. Electroadsorption-assisted direct determination of trace arsenic without interference using transmission X-ray fluorescence spectroscopy.

    Science.gov (United States)

    Jiang, Tian-Jia; Guo, Zheng; Liu, Jin-Huai; Huang, Xing-Jiu

    2015-08-18

    An analytical technique based on electroadsorption and transmission X-ray fluorescence (XRF) for the quantitative determination of arsenic in aqueous solution with ppb-level limits of detection (LOD) is proposed. The approach uses electroadsorption to enhance the sensitivity and LOD of the arsenic XRF response. Amine-functionalized carbonaceous microspheres (NH2-CMSs) are found to be the ideal materials for both the quantitative adsorption of arsenic and XRF analysis due to the basic amine sites on the surface and their noninterference in the XRF spectrum. In electroadsorptive X-ray fluorescence (EA-XRF), arsenic is preconcentrated by a conventional three-electrode system with a positive electricity field around the adsorbents. Then, the quantification of arsenic on the adsorbents is achieved using XRF. The electroadsorption preconcentration can realize the fast transfer of arsenic from the solution to the adsorbents and improve the LOD of conventional XRF compared with directly determining arsenic solution by XRF alone. The sensitivity of 0.09 cnt ppb(-1) is obtained without the interferences from coexisted metal ions in the determination of arsenic, and the LOD is found to be 7 ppb, which is lower than the arsenic guideline value of 10 ppb given by the World Health Organization (WHO). These results demonstrated that XRF coupled with electroadsorption was able to determine trace arsenic in real water sample.

  17. Background species effect on aqueous arsenic removal by nano zero-valent iron using fractional factorial design.

    Science.gov (United States)

    Tanboonchuy, Visanu; Grisdanurak, Nurak; Liao, Chih-Hsiang

    2012-02-29

    This study describes the removal of arsenic species in groundwater by nano zero-valent iron process, including As(III) and As(V). Since the background species may inhibit or promote arsenic removal. The influence of several common ions such as phosphate (PO4(3-)), bicarbonate (HCO3-)), sulfate (SO4(2-)), calcium (Ca2+), chloride (Cl-), and humic acid (HA) were selected to evaluate their effects on arsenic removal. In particular, a 2(6-2) fractional factorial design (FFD) was employed to identify major or interacting factors, which affect arsenic removal in a significant way. As a result of FFD evaluation, PO4(3-) and HA play the role of inhibiting arsenic removal, while Ca2+ was observed to play the promoting one. As for HCO3- and Cl-, the former one inhibits As(III) removal, whereas the later one enhances its removal; on the other hand, As(V) removal was affected only slightly in the presence of HCO3- or Cl-. Hence, it was suggested that the arsenic removal by the nanoiron process can be improved through pretreatment of PO4(3-) and HA. In addition, for the groundwater with high hardness, the nanoiron process can be an advantageous option because of enhancing characteristics of Ca2+. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Converging strategies by farmers and scientists to improve soil fertility and enhance crop production in Benin

    NARCIS (Netherlands)

    Saidou, A.

    2006-01-01

    Keywords: Farmer perception, indigenous knowledge, extensive cassava, earthworm casts, arbuscular mycorrhiza, crop rotation, nutrient uptake, soil fertility, co-research, land tenure.Farmers in the transitional zone of Benin claim that extensive cassava cropping and prior cotton fertiliser enhance

  19. Significantly increased risk of carotid atherosclerosis with arsenic exposure and polymorphisms in arsenic metabolism genes

    International Nuclear Information System (INIS)

    Hsieh, Yi-Chen; Lien, Li-Ming; Chung, Wen-Ting; Hsieh, Fang-I; Hsieh, Pei-Fan; Wu, Meei-Maan; Tseng, Hung-Pin; Chiou, Hung-Yi; Chen, Chien-Jen

    2011-01-01

    Individual susceptibility to arsenic-induced carotid atherosclerosis might be associated with genetic variations in arsenic metabolism. The purpose of this study is to explore the interaction effect on risk of carotid atherosclerosis between arsenic exposure and risk genotypes of purine nucleoside phosphorylase (PNP), arsenic (+3) methyltransferase (As3MT), and glutathione S-transferase omega 1 (GSTO1) and omega 2 (GSTO2). A community-based case-control study was conducted in northeastern Taiwan to investigate the arsenic metabolic-related genetic susceptibility to carotid atherosclerosis. In total, 863 subjects, who had been genotyped and for whom the severity of carotid atherosclerosis had been determined, were included in the present study. Individual well water was collected and arsenic concentration determined using hydride generation combined with flame atomic absorption spectrometry. The result showed that a significant dose-response trend (P=0.04) of carotid atherosclerosis risk associated with increasing arsenic concentration. Non-significant association between genetic polymorphisms of PNP Gly51Ser, Pro57Pro, As3MT Met287Thr, GSTO1 Ala140Asp, and GSTO2 A-183G and the risk for development of carotid atherosclerosis were observed. However, the significant interaction effect on carotid atherosclerosis risk was found for arsenic exposure (>50 μg/l) and the haplotypes of PNP (p=0.0115). A marked elevated risk of carotid atherosclerosis was observed in subjects with arsenic exposure of >50 μg/l in drinking water and those who carried the PNP A-T haplotype and at least either of the As3MT risk polymorphism or GSTO risk haplotypes (OR, 6.43; 95% CI, 1.79-23.19). In conclusion, arsenic metabolic genes, PNP, As3MT, and GSTO, may exacerbate the formation of atherosclerosis in individuals with high levels of arsenic concentration in well water (>50 μg/l). - Highlights: →Arsenic metabolic genes might be associated with carotid atherosclerosis. → A case

  20. Significantly increased risk of carotid atherosclerosis with arsenic exposure and polymorphisms in arsenic metabolism genes

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, Yi-Chen [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Lien, Li-Ming [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); School of Medicine, Taipei Medical University, Taipei, Taiwan (China); Department of Neurology, Shin Kong WHS Memorial Hospital, Taipei, Taiwan (China); Chung, Wen-Ting [Department of Neurology, Wanfang Hospital, Taipei Medical University, Taipei, Taiwan (China); Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan (China); Hsieh, Fang-I; Hsieh, Pei-Fan [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Wu, Meei-Maan [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Graduate Institute of Basic Medicine, College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan (China); Tseng, Hung-Pin [Department of Neurology, Lotung Poh-Ai Hospital, I-Lan, Taiwan (China); Chiou, Hung-Yi, E-mail: hychiou@tmu.edu.tw [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Chen, Chien-Jen [Genomics Research Center, Academia Sinica, Taipei, Taiwan (China)

    2011-08-15

    Individual susceptibility to arsenic-induced carotid atherosclerosis might be associated with genetic variations in arsenic metabolism. The purpose of this study is to explore the interaction effect on risk of carotid atherosclerosis between arsenic exposure and risk genotypes of purine nucleoside phosphorylase (PNP), arsenic (+3) methyltransferase (As3MT), and glutathione S-transferase omega 1 (GSTO1) and omega 2 (GSTO2). A community-based case-control study was conducted in northeastern Taiwan to investigate the arsenic metabolic-related genetic susceptibility to carotid atherosclerosis. In total, 863 subjects, who had been genotyped and for whom the severity of carotid atherosclerosis had been determined, were included in the present study. Individual well water was collected and arsenic concentration determined using hydride generation combined with flame atomic absorption spectrometry. The result showed that a significant dose-response trend (P=0.04) of carotid atherosclerosis risk associated with increasing arsenic concentration. Non-significant association between genetic polymorphisms of PNP Gly51Ser, Pro57Pro, As3MT Met287Thr, GSTO1 Ala140Asp, and GSTO2 A-183G and the risk for development of carotid atherosclerosis were observed. However, the significant interaction effect on carotid atherosclerosis risk was found for arsenic exposure (>50 {mu}g/l) and the haplotypes of PNP (p=0.0115). A marked elevated risk of carotid atherosclerosis was observed in subjects with arsenic exposure of >50 {mu}g/l in drinking water and those who carried the PNP A-T haplotype and at least either of the As3MT risk polymorphism or GSTO risk haplotypes (OR, 6.43; 95% CI, 1.79-23.19). In conclusion, arsenic metabolic genes, PNP, As3MT, and GSTO, may exacerbate the formation of atherosclerosis in individuals with high levels of arsenic concentration in well water (>50 {mu}g/l). - Highlights: {yields}Arsenic metabolic genes might be associated with carotid atherosclerosis. {yields

  1. Evaluation of Redox Conditions and Enhanced Arsenic Mobility from Waste Disposal in a Complex Fractured Crystalline-Rock Aquifer, Raymond, New Hampshire, USA (Note: article rewritten under new title)

    Science.gov (United States)

    (Note: This entry is no longer valid; the paper was rewritten and submitted to a different journal.) This paper highlights some methods that can be used at a local scale to assess whether waste disposal activities are responsible for enhanced arsenic mobility through redox-contro...

  2. [Regulatory genes of garden pea (Pisum sativum L.) controlling the development of nitrogen-fixing nodules and arbuscular mycorrhiza: a review of basic and applied aspects

    DEFF Research Database (Denmark)

    Borisov, A Iu; Vasil'chikov, A G; Voroshilova, V A

    2007-01-01

    The review sums up the long experience of the authors and other researchers in studying the genetic system of garden pea (Pisum sativum L.), which controls sthe development of nitrogen-fixing symbiosis and arbuscular mycorrhiza. A justified phenotypic classification of pea mutants is presented....... Progress in identifying and cloning symbiotic genes is adequately reflected. The feasibility of using double inoculation as a means of increasing the plant productivity is demonstrated, in which the potential of a tripartite symbiotic system (pea plants-root nodule bacteria-arbuscular mycorrhiza...

  3. Arsenic removal from water using a novel amorphous adsorbent developed from coal fly ash.

    Science.gov (United States)

    Zhang, Kaihua; Zhang, Dongxue; Zhang, Kai

    2016-01-01

    A novel effective adsorbent of alumina/silica oxide hydrate (ASOH) for arsenic removal was developed through simple chemical reactions using coal fly ash. The iron-modified ASOH with enhancing adsorption activity was further developed from raw fly ash based on the in situ technique. The adsorbents were characterized by X-ray diffraction, Fourier transform infrared spectrometry, scanning electron micrograph, laser particle size and Brunauer-Emmet-Teller surface area. The results show that the adsorbents are in amorphous and porous structure, the surface areas of which are 8-12 times that of the raw ash. The acidic hydrothermal treatment acts an important role in the formation of the amorphous structure of ASOH rather than zeolite crystal. A series of adsorption experiments for arsenic on them were studied. ASOH can achieve a high removal efficiency for arsenic of 96.4% from water, which is more than 2.5 times that of the raw ash. Iron-modified ASOH can enhance the removal efficiency to reach 99.8% due to the in situ loading of iron (Fe). The condition of synthesis pH = 2-4 is better for iron-modified ASOH to adsorb arsenic from water.

  4. Arsenic concentrations in Chinese coals

    International Nuclear Information System (INIS)

    Wang Mingshi; Zheng Baoshan; Wang Binbin; Li Shehong; Wu Daishe; Hu Jun

    2006-01-01

    The arsenic concentrations in 297 coal samples were collected from the main coal-mines of 26 provinces in China were determined by molybdenum blue coloration method. These samples were collected from coals that vary widely in coal rank and coal-forming periods from the five main coal-bearing regions in China. Arsenic content in Chinese coals range between 0.24 to 71 mg/kg. The mean of the concentration of Arsenic is 6.4 ± 0.5 mg/kg and the geometric mean is 4.0 ± 8.5 mg/kg. The level of arsenic in China is higher in northeastern and southern provinces, but lower in northwestern provinces. The relationship between arsenic content and coal-forming period, coal rank is studied. It was observed that the arsenic contents decreases with coal rank in the order: Tertiary > Early Jurassic > Late Triassic > Late Jurassic > Middle Jurassic > Late Permian > Early Carboniferous > Middle Carboniferous > Late Carboniferous > Early Permian; It was also noted that the arsenic contents decrease in the order: Subbituminous > Anthracite > Bituminous. However, compared with the geological characteristics of coal forming region, coal rank and coal-forming period have little effect on the concentration of arsenic in Chinese coal. The average arsenic concentration of Chinese coal is lower than that of the whole world. The health problems in China derived from in coal (arsenism) are due largely to poor local life-style practices in cooking and home heating with coal rather than to high arsenic contents in the coal

  5. Arsenic silences hepatic PDK4 expression through activation of histone H3K9 methylatransferase G9a

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xi; Wu, Jianguo; Choiniere, Jonathan [Department of Physiology and Neurobiology and The Institute for Systems Genomics, University of Connecticut, Storrs, CT 062696 (United States); Yang, Zhihong [Department of Physiology and Neurobiology and The Institute for Systems Genomics, University of Connecticut, Storrs, CT 062696 (United States); Veterans Affairs Connecticut Healthcare System, West Haven, CT 06516 (United States); Huang, Yi [Department of Physiology and Neurobiology and The Institute for Systems Genomics, University of Connecticut, Storrs, CT 062696 (United States); School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035 (China); Bennett, Jason [Department of Physiology and Neurobiology and The Institute for Systems Genomics, University of Connecticut, Storrs, CT 062696 (United States); Wang, Li, E-mail: li.wang@uconn.edu [Department of Physiology and Neurobiology and The Institute for Systems Genomics, University of Connecticut, Storrs, CT 062696 (United States); Veterans Affairs Connecticut Healthcare System, West Haven, CT 06516 (United States); School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035 (China); Department of Internal Medicine, Section of Digestive Diseases, Yale University, New Haven, CT 06520 (United States)

    2016-08-01

    It is well established that increased liver cancer incidence is strongly associated with epigenetic silencing of tumor suppressor genes; the latter is contributed by the environmental exposure to arsenic. Pyruvate dehydrogenase kinase 4 (PDK4) is a mitochondrial protein that regulates the TCA cycle. However, the epigenetic mechanisms mediated by arsenic to control PDK4 expression remain elusive. In the present study, we showed that histone methyltransferase G9a- and Suv39H-mediated histone H3 lysine 9 (H3K9) methylations contributed to PDK4 silencing in hepatic cells. The PDK4 expression was induced by G9a inhibitor BRD4770 (BRD) and Suv39H inhibitor Chaetocin (CHA). In contrast, arsenic exposure decreased PDK4 expression by inducing G9a and increasing H3K9 di- and tri-methylations levels (H3K9me2/3). In addition, arsenic exposure antagonizes the effect of BRD by enhancing the enrichment of H3K9me2/3 in the PKD4 promoter. Moreover, knockdown of G9a using siRNA induced PDK4 expression in HCC cells. Furthermore, arsenic decreased hepatic PDK4 expression as well as diminished the induction of PDK4 by BRD in mouse liver and hepatocytes. Overall, the results suggest that arsenic causes aberrant repressive histone modification to silence PDK4 in both HCC cells and in mouse liver. - Graphical abstract: Schematic showing arsenic-mediated epigenetic pathway that inhibits PDK4 expression. (A) BRD induces PDK4 expression by decreasing G9a protein and histone H3K9me2 and H3K9me3 levels as well as diminishing their recruitment to the PDK4 promoter. (B) Arsenic counteracts the effect of BRD by increasing histone H3K9me2 and H3K9me3 levels as well as enhancing their enrichment to the PDK4 promoter. Display Omitted - Highlights: • Histone methyltrasferase G9a inhibitor BRD induces PDK4 expression. • Arsenic decreases PDK4 expression and increases H3K9me2 and me3 levels. • Arsenic enhances H3K9me2/me3 enrichment in the PDK4 promoter. • Arsenic antagonizes the activation of

  6. Arsenic silences hepatic PDK4 expression through activation of histone H3K9 methylatransferase G9a

    International Nuclear Information System (INIS)

    Zhang, Xi; Wu, Jianguo; Choiniere, Jonathan; Yang, Zhihong; Huang, Yi; Bennett, Jason; Wang, Li

    2016-01-01

    It is well established that increased liver cancer incidence is strongly associated with epigenetic silencing of tumor suppressor genes; the latter is contributed by the environmental exposure to arsenic. Pyruvate dehydrogenase kinase 4 (PDK4) is a mitochondrial protein that regulates the TCA cycle. However, the epigenetic mechanisms mediated by arsenic to control PDK4 expression remain elusive. In the present study, we showed that histone methyltransferase G9a- and Suv39H-mediated histone H3 lysine 9 (H3K9) methylations contributed to PDK4 silencing in hepatic cells. The PDK4 expression was induced by G9a inhibitor BRD4770 (BRD) and Suv39H inhibitor Chaetocin (CHA). In contrast, arsenic exposure decreased PDK4 expression by inducing G9a and increasing H3K9 di- and tri-methylations levels (H3K9me2/3). In addition, arsenic exposure antagonizes the effect of BRD by enhancing the enrichment of H3K9me2/3 in the PKD4 promoter. Moreover, knockdown of G9a using siRNA induced PDK4 expression in HCC cells. Furthermore, arsenic decreased hepatic PDK4 expression as well as diminished the induction of PDK4 by BRD in mouse liver and hepatocytes. Overall, the results suggest that arsenic causes aberrant repressive histone modification to silence PDK4 in both HCC cells and in mouse liver. - Graphical abstract: Schematic showing arsenic-mediated epigenetic pathway that inhibits PDK4 expression. (A) BRD induces PDK4 expression by decreasing G9a protein and histone H3K9me2 and H3K9me3 levels as well as diminishing their recruitment to the PDK4 promoter. (B) Arsenic counteracts the effect of BRD by increasing histone H3K9me2 and H3K9me3 levels as well as enhancing their enrichment to the PDK4 promoter. Display Omitted - Highlights: • Histone methyltrasferase G9a inhibitor BRD induces PDK4 expression. • Arsenic decreases PDK4 expression and increases H3K9me2 and me3 levels. • Arsenic enhances H3K9me2/me3 enrichment in the PDK4 promoter. • Arsenic antagonizes the activation of

  7. 32P uptake and translocation in chickpea (Cicer arietinum L.) inoculated with vesicular-arbuscular mycorrhiza

    International Nuclear Information System (INIS)

    Chaturvedi, C.; Singh, Renu

    1990-01-01

    32 P uptake in chickpea (Cicer arietinum L.) cultivars L-550 and C-235 as affected by vesicualr-arbuscular mycorrhiza (G. caledonicum) and Rhizobium was investigated in P deficient soils. Test plants coinoculated with the above two symbionts exhibited higher 32 P uptake than inoculated with either symbiont alone. Uninoculated plants showed minimum level of 32 P uptake. (author). 1 tab., 7 refs

  8. Arsenic responsive microRNAs in vivo and their potential involvement in arsenic-induced oxidative stress

    International Nuclear Information System (INIS)

    Ren, Xuefeng; Gaile, Daniel P.; Gong, Zhihong; Qiu, Wenting; Ge, Yichen; Zhang, Chuanwu; Huang, Chenping; Yan, Hongtao; Olson, James R.; Kavanagh, Terrance J.; Wu, Hongmei

    2015-01-01

    Arsenic exposure is postulated to modify microRNA (miRNA) expression, leading to changes of gene expression and toxicities, but studies relating the responses of miRNAs to arsenic exposure are lacking, especially with respect to in vivo studies. We utilized high-throughput sequencing technology and generated miRNA expression profiles of liver tissues from Sprague Dawley (SD) rats exposed to various concentrations of sodium arsenite (0, 0.1, 1, 10 and 100 mg/L) for 60 days. Unsupervised hierarchical clustering analysis of the miRNA expression profiles clustered the SD rats into different groups based on the arsenic exposure status, indicating a highly significant association between arsenic exposure and cluster membership (p-value of 0.0012). Multiple miRNA expressions were altered by arsenic in an exposure concentration-dependent manner. Among the identified arsenic-responsive miRNAs, several are predicted to target Nfe2l2-regulated antioxidant genes, including glutamate–cysteine ligase (GCL) catalytic subunit (GCLC) and modifier subunit (GCLM) which are involved in glutathione (GSH) synthesis. Exposure to low concentrations of arsenic increased mRNA expression for Gclc and Gclm, while high concentrations significantly reduced their expression, which were correlated to changes in hepatic GCL activity and GSH level. Moreover, our data suggested that other mechanisms, e.g., miRNAs, rather than Nfe2l2-signaling pathway, could be involved in the regulation of mRNA expression of Gclc and Gclm post-arsenic exposure in vivo. Together, our findings show that arsenic exposure disrupts the genome-wide expression of miRNAs in vivo, which could lead to the biological consequence, such as an altered balance of antioxidant defense and oxidative stress. - Highlights: • Chronic arsenic exposure induces changes of hepatic miRNA expression profiles. • Hepatic GCL activity and GSH level in rats are altered following arsenic exposure. • Arsenic induced GCL expression change is

  9. Arsenic responsive microRNAs in vivo and their potential involvement in arsenic-induced oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Xuefeng, E-mail: xuefengr@buffalo.edu [Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, The State University of New York, Buffalo, NY 14214 (United States); Department of Pharmacology and Toxicology, School of Biomedical Sciences, The State University of New York, Buffalo, NY 14214 (United States); Gaile, Daniel P. [Department of Biostatistics, School of Public Health and Health Professions, the State University of New York, Buffalo, NY 14214 (United States); Gong, Zhihong [Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, The State University of New York, Buffalo, NY 14214 (United States); Qiu, Wenting [School of Public Health, Wenzhou Medical University, Wenzhou, Zhejiang 325035 (China); Ge, Yichen [Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, The State University of New York, Buffalo, NY 14214 (United States); Zhang, Chuanwu; Huang, Chenping; Yan, Hongtao [School of Public Health, Wenzhou Medical University, Wenzhou, Zhejiang 325035 (China); Olson, James R. [Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, The State University of New York, Buffalo, NY 14214 (United States); Department of Pharmacology and Toxicology, School of Biomedical Sciences, The State University of New York, Buffalo, NY 14214 (United States); Kavanagh, Terrance J. [Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195 (United States); Wu, Hongmei, E-mail: hongmeiwwu@hotmail.com [School of Public Health, Wenzhou Medical University, Wenzhou, Zhejiang 325035 (China)

    2015-03-15

    Arsenic exposure is postulated to modify microRNA (miRNA) expression, leading to changes of gene expression and toxicities, but studies relating the responses of miRNAs to arsenic exposure are lacking, especially with respect to in vivo studies. We utilized high-throughput sequencing technology and generated miRNA expression profiles of liver tissues from Sprague Dawley (SD) rats exposed to various concentrations of sodium arsenite (0, 0.1, 1, 10 and 100 mg/L) for 60 days. Unsupervised hierarchical clustering analysis of the miRNA expression profiles clustered the SD rats into different groups based on the arsenic exposure status, indicating a highly significant association between arsenic exposure and cluster membership (p-value of 0.0012). Multiple miRNA expressions were altered by arsenic in an exposure concentration-dependent manner. Among the identified arsenic-responsive miRNAs, several are predicted to target Nfe2l2-regulated antioxidant genes, including glutamate–cysteine ligase (GCL) catalytic subunit (GCLC) and modifier subunit (GCLM) which are involved in glutathione (GSH) synthesis. Exposure to low concentrations of arsenic increased mRNA expression for Gclc and Gclm, while high concentrations significantly reduced their expression, which were correlated to changes in hepatic GCL activity and GSH level. Moreover, our data suggested that other mechanisms, e.g., miRNAs, rather than Nfe2l2-signaling pathway, could be involved in the regulation of mRNA expression of Gclc and Gclm post-arsenic exposure in vivo. Together, our findings show that arsenic exposure disrupts the genome-wide expression of miRNAs in vivo, which could lead to the biological consequence, such as an altered balance of antioxidant defense and oxidative stress. - Highlights: • Chronic arsenic exposure induces changes of hepatic miRNA expression profiles. • Hepatic GCL activity and GSH level in rats are altered following arsenic exposure. • Arsenic induced GCL expression change is

  10. Lake Mixing Regime Influences Arsenic Transfer from Sediments into the Water Column and Uptake in Plankton

    Science.gov (United States)

    Gawel, J.; Barrett, P. M.; Hull, E.; Burkart, K.; McLean, J.; Hargrave, O.; Neumann, R.

    2017-12-01

    The former ASARCO copper smelter in Ruston, WA, now a Superfund site, contaminated a large area of the south-central Puget Sound region with arsenic over its almost 100-year history. Arsenic, a priority Superfund contaminant and carcinogen, is a legacy pollutant impacting aquatic ecosystems in urban lakes downwind of the ASARCO emissions stack. We investigated the impact of lake mixing regime on arsenic transfer from sediments into lake water and aquatic biota. We regularly collected water column and plankton samples from four study lakes for two years, and deployed sediment porewater peepers and sediment traps to estimate arsenic flux rates to and from the sediments. In lakes with strong seasonal stratification, high aqueous arsenic concentrations were limited to anoxic hypolimnetic waters while low arsenic concentrations were observed in oxic surface waters. However, in polymictic, shallow lakes, we observed elevated arsenic concentrations throughout the entire oxic water column. Sediment flux estimates support higher rates of arsenic release from sediments and vertical transport. Because high arsenic in oxic waters results in spatial overlap between arsenate, a phosphate analog, and lake biota, we observed enhanced trophic transfer of arsenic in polymictic, shallow study lakes, with higher arsenic accumulation (up to an order of magnitude) in both phytoplankton and zooplankton compared to stratified lakes. Chemical and physical mechanisms for higher steady-state arsenic concentrations will be explored. Our work demonstrates that physical mixing processes coupled with sediment/water redox status exert significant control over bioaccumulation, making shallow, periodically-mixed urban lakes uniquely vulnerable to environmental and human health risks from legacy arsenic contamination.

  11. Microvascular dysfunction with increased vascular leakage response in mice systemically exposed to arsenic.

    Science.gov (United States)

    Chen, Shih-Chieh; Huang, Shin-Yin; Lu, Chi-Yu; Hsu, Ya-Hung; Wang, Dean-Chuan

    2014-09-01

    The mechanisms underlying cardiovascular disease induced by arsenic exposure are not completely understood. The objectives of this study were to investigate whether arsenic-fed mice have an increased vascular leakage response to vasoactive agents and whether enhanced type-2 protein phosphatase (PP2A) activity is involved in mustard oil-induced leakage. ICR mice were fed water or sodium arsenite (20 mg/kg) for 4 or 8 weeks. The leakage response to vasoactive agents was quantified using the Evans blue (EB) technique or vascular labeling with carbon particles. Increased EB leakage and high density of carbon-labeled microvessels were detected in arsenic-fed mice treated with mustard oil. Histamine induced significantly higher vascular leakage in arsenic-fed mice than in water-fed mice. Pretreatment with the PP2A inhibitor okadaic acid or the neurokinin 1 receptor (NK1R) blocker RP67580 significantly reduced mustard oil-induced vascular leakage in arsenic-fed mice. The protein levels of PP2Ac and NK1R were similar in both groups. PP2A activity was significantly higher in the arsenic-fed mice compared with the control group. These findings indicate that microvessels generally respond to vasoactive agents, and that the increased PP2A activity is involved in mustard oil-induced vascular leakage in arsenic-fed mice. Arsenic may initiate endothelial dysfunction, resulting in vascular leakage in response to vasoactive agents.

  12. Arsenic and dichlorvos: Possible interaction between two environmental contaminants.

    Science.gov (United States)

    Flora, Swaran J S

    2016-05-01

    Metals are ubiquitously present in the environment and pesticides are widely used throughout the world. Environmental and occupational exposure to metal along with pesticide is an area of great concern to both the public and regulatory authorities. Our major concern is that combination of these toxicant present in environment may elicit toxicity either due to additive or synergistic interactions or 'joint toxic actions' among these toxicants. It poses a rising threat to human health. Water contamination particularly ground water contamination with arsenic is a serious problem in today's scenario since arsenic is associated with several kinds of health problems, such arsenic associated health anomalies are commonly called as 'Arsenism'. Uncontrolled use and spillage of pesticides into the environment has resulted in alarming situation. Moreover serious concerns are being addressed due to their persistence in the environmental matrices such as air, soil and surface water runoff resulting in continuous exposure of these harmful chemicals to human beings and animals. Bio-availability of these environmental toxicants has been enhanced much due to anthropological activities. Dreadfully very few studies are available on combined exposures to these toxicants on the animal or human system. Studies on the acute and chronic exposure to arsenic and DDVP are well reported and well defined. Arsenic is a common global ground water contaminant while dichlorvos is one of the most commonly and widely employed organophosphate based insecticide used in agriculture, horticulture etc. There is thus a real situation where a human may get exposed to these toxicants while working in a field. This review highlights the individual and combined exposure to arsenic and dichlorvos on health. Copyright © 2016 Elsevier GmbH. All rights reserved.

  13. Mycorrhizas and soil ecosystem function of co-existing woody vegetation islands at the alpine tree line

    Czech Academy of Sciences Publication Activity Database

    Wang, L.; Otgonsuren, B.; Godbold, Douglas

    2017-01-01

    Roč. 411, 1-2 (2017), s. 467-481 ISSN 0032-079X R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : Ectoenzymes * Ectomycorrhizas * Enzyme activity * Ericoid mycorrhizas * Nitrogen-mineralization Subject RIV: EF - Botanics OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 3.052, year: 2016

  14. Low level arsenic promotes progressive inflammatory angiogenesis and liver blood vessel remodeling in mice

    International Nuclear Information System (INIS)

    Straub, Adam C.; Stolz, Donna B.; Vin, Harina; Ross, Mark A.; Soucy, Nicole V.; Klei, Linda R.; Barchowsky, Aaron

    2007-01-01

    The vascular effects of arsenic in drinking water are global health concerns contributing to human disease worldwide. Arsenic targets the endothelial cells lining blood vessels, and endothelial cell activation or dysfunction may underlie the pathogenesis of both arsenic-induced vascular diseases and arsenic-enhanced tumorigenesis. The purpose of the current studies was to demonstrate that exposing mice to drinking water containing environmentally relevant levels of arsenic promoted endothelial cell dysfunction and pathologic vascular remodeling. Increased angiogenesis, neovascularization, and inflammatory cell infiltration were observed in Matrigel plugs implanted in C57BL/6 mice following 5-week exposures to 5-500 ppb arsenic [Soucy, N.V., Mayka, D., Klei, L.R., Nemec, A.A., Bauer, J.A., Barchowsky, A., 2005. Neovascularization and angiogenic gene expression following chronic arsenic exposure in mice. Cardiovasc.Toxicol 5, 29-42]. Therefore, functional in vivo effects of arsenic on endothelial cell function and vessel remodeling in an endogenous vascular bed were investigated in the liver. Liver sinusoidal endothelial cells (LSEC) became progressively defenestrated and underwent capillarization to decrease vessel porosity following exposure to 250 ppb arsenic for 2 weeks. Sinusoidal expression of PECAM-1 and laminin-1 proteins, a hallmark of capillarization, was also increased by 2 weeks of exposure. LSEC caveolin-1 protein and caveolae expression were induced after 2 weeks of exposure indicating a compensatory change. Likewise, CD45/CD68-positive inflammatory cells did not accumulate in the livers until after LSEC porosity was decreased, indicating that inflammation is a consequence and not a cause of the arsenic-induced LSEC phenotype. The data demonstrate that the liver vasculature is an early target of pathogenic arsenic effects and that the mouse liver vasculature is a sensitive model for investigating vascular health effects of arsenic

  15. Phytoremediation of arsenic contaminated soil by Pteris vittata L. I. Influence of phosphatic fertilizers and repeated harvests.

    Science.gov (United States)

    Mandal, Asit; Purakayastha, T J; Patra, A K; Sanyal, S K

    2012-12-01

    A greenhouse experiment was conducted to evaluate the effectiveness of diammonium phosphate (DAP), single superphosphate (SSP) and two growing cycles on arsenic removal by Chinese Brake Fern (Pteris vittata L.) from an arsenic contaminated Typic Haplustept of the Indian state of West Bengal. After harvest of Pteris vittata the total, Olsen's extractable and other five soil arsenic fractions were determined. The total biomass yield of P. vittata ranged from 10.7 to 16.2 g pot(-1) in first growing cycle and from 7.53 to 11.57 g pot(-1) in second growing cycle. The frond arsenic concentrations ranged from 990 to 1374 mg kg(-1) in first growing cycle and from 875 to 1371 mg kg(-1) in second growing cycle. DAP was most efficient in enhancing biomass yield, frond and root arsenic concentrations and total arsenic removal from soil. After first growing cycle, P. vittata reduced soil arsenic by 10 to 20%, while after two growing cycles Pteris reduced it by 18 to 34%. Among the different arsenic fractions, Fe-bound arsenic dominated over other fractions. Two successive harvests with DAP as the phosphate fertilizer emerged as the promising management strategy for amelioration of arsenic contaminated soil of West Bengal through phyotoextraction by P. vittata.

  16. Unravelling mycorrhiza-induced wheat susceptibility to the English grain aphid Sitobion avenae

    Science.gov (United States)

    Simon, Amma L.; Wellham, Peter A. D.; Aradottir, Gudbjorg I.; Gange, Alan C.

    2017-04-01

    Arbuscular mycorrhizal (AM) fungi are root symbionts that can increase or decrease aphid growth rates and reproduction, but the reason by which this happens is unknown. To investigate the underlying mechanisms of this interaction, we examined the effect of AM fungi on the English Grain aphid (Sitobion avenae) development, reproduction, attraction, settlement and feeding behaviour on two naturally susceptible varieties Triticum aestivum (L.) variety Solstice and T. monococcum MDR037, and two naturally resistant lines, T. monococcum MDR045 and MDR049. Mycorrhizal colonisation increased the attractiveness of T. aestivum var. Solstice to aphids, but there was no effect on aphid development on this variety. Using the Electrical Penetration Graph (EPG) technique, we found that mycorrhizal colonisation increased aphid phloem feeding on T. monococcum MDR037 and MDR045, colonisation also increased growth rate and reproductive success of S. avenae on these varieties. Mycorrhizas increased vascular bundle size, demonstrating that these fungi can influence plant anatomy. We discuss if and how this could be related to an enhanced success rate in phloem feeding in two varieties. Overall, we present and discuss how mycorrhizal fungi can affect the feeding behaviour of S. avenae in wheat, inducing susceptibility in a resistant variety.

  17. Determination of total arsenic in soil and arsenic-resistant bacteria from selected ground water in Kandal Province, Cambodia

    International Nuclear Information System (INIS)

    Hamzah, A.; Wong, K.K.; Hasan, F.N.; Mustafa, S.; Khoo, K.S.; Sarmani, S.B.

    2013-01-01

    Cambodia has geological environments conducive to generation of high-arsenic groundwater and people are at high risk of chronic arsenic exposure. The aims of this study are to investigate the concentration of total arsenic and to isolate and identify arsenic-resistant bacteria from selected locations in Kandal Province, Cambodia. The INAA technique was used to measure the concentration of total arsenic in soils. The arsenic concentrations in soils were above permissible 5 mg/kg, ranging from 5.34 to 27.81 mg/kg. Bacteria resistant to arsenic from two arsenic-contaminated wells in Preak Russey were isolated by enrichment method in nutrient broth (NB). Colonies isolated from NB was then grown on minimal salt media (MSM) added with arsenic at increasing concentrations of 10, 20, 30, 50, 100 and 250 ppm. Two isolates that can tolerate 750 ppm of arsenic were identified as Enterobacter agglomerans and Acinetobacter lwoffii based on a series of biochemical, physiological and morphological analysis. Optimum growth of both isolates ranged from pH 6.6 to 7.0 and 30-35 deg C. E. agglomerans and A. lwoffii were able to remove 66.4 and 64.1 % of arsenic, respectively at the initial concentration of 750 ppm, within 72 h of incubation. Using energy dispersive X-ray technique, the percentage of arsenic absorbed by E. agglomerans and A. lwoffii was 0.09 and 0.15 %, respectively. This study suggested that arsenic-resistant E. agglomerans and A. lwoffii removed arsenic from media due to their ability to absorb arsenic. (author)

  18. APPARENT LACK OF VESICULAR-ARBUSCULAR MYCORRHIZA (VAM) IN SEAGRASSES ZOSTERA MARINA L. AND THALASSIA TESTUDIUM BANKS EX KONIG

    Science.gov (United States)

    We examined two populations of Zostera marina L. and one of Thalassia testudinum Banks ex Konig for presence of vesicular-arbuscular mycorrhiza (VAM). None of these plants showed any VAM colonization. In addition, we were unable to find any literature references on the presence o...

  19. [Arsenical keratosis treated by dermatome shaving].

    Science.gov (United States)

    Kjerkegaard, Ulrik Knap; Heje, Jens Martin; Vestergaard, Christian; Stausbøl-Grøn, Birgitte; Stolle, Lars Bjørn

    2014-05-05

    Cutaneous malignancy in association with arsenic exposure is a rare but well-documented phenomenon. Signs of chronic arsenic exposure are very rare in Denmark today. However, arsenic was used in the medical treatment of psoriasis vulgaris up till the 1980's and several patients suffer from this arsenic treatment today. This case report shows that arsenical keratosis can be treated by dermatome shaving, a superficial destructive therapy.

  20. In situ treatment of arsenic contaminated groundwater by aquifer iron coating: Experimental study.

    Science.gov (United States)

    Xie, Xianjun; Wang, Yanxin; Pi, Kunfu; Liu, Chongxuan; Li, Junxia; Liu, Yaqing; Wang, Zhiqiang; Duan, Mengyu

    2015-09-15

    In situ arsenic removal from groundwater by an aquifer iron coating method has great potential to be a cost effective and simple groundwater remediation technology, especially in rural and remote areas where groundwater is used as the main water source for drinking. The in situ arsenic removal technology was first optimized by simulating arsenic removal in various quartz sand columns under anoxic conditions. The effectiveness was then evaluated in an actual high-arsenic groundwater environment. The arsenic removal mechanism by the coated iron oxide/hydroxide was investigated under different conditions using scanning electron microscopy (SEM)/X-ray absorption spectroscopy, electron probe microanalysis, and Fourier transformation infrared spectroscopy. Aquifer iron coating method was developed via a 4-step alternating injection of oxidant, iron salt and oxygen-free water. A continuous injection of 5.0 mmol/L FeSO4 and 2.5 mmol/L NaClO for 96 h can form a uniform goethite coating on the surface of quartz sand without causing clogging. At a flow rate of 7.2 mL/min of the injection reagents, arsenic (as Na2HAsO4) and tracer fluorescein sodium to pass through the iron-coated quartz sand column were approximately at 126 and 7 column pore volumes, respectively. The retardation factor of arsenic was 23.0, and the adsorption capacity was 0.11 mol As per mol Fe. In situ arsenic removal from groundwater in an aquifer was achieved by simultaneous injections of As(V) and Fe(II) reagents. Arsenic fixation resulted from a process of adsorption/co-precipitation with fine goethite particles by way of bidentate binuclear complexes. Therefore, the study results indicate that the high arsenic removal efficiency of the in situ aquifer iron coating technology likely resulted from the expanded specific surface area of the small goethite particles, which enhanced arsenic sorption capability and/or from co-precipitation of arsenic on the surface of goethite particles. Copyright © 2015

  1. Effects of arsenic on nitrate metabolism in arsenic hyperaccumulating and non-hyperaccumulating ferns

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Nandita [Soil and Water Science Department, University of Florida, Gainesville, Fl 32611-0290 (United States); Eco-Auditing group, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226 001 (India); Ma, Lena Q., E-mail: lqma@ufl.ed [Soil and Water Science Department, University of Florida, Gainesville, Fl 32611-0290 (United States); Vu, Joseph C. [Chemistry Research Unit, CMAVE, USDA-ARS, Gainesville, FL 32608-1069 and Agronomy Department, University of Florida, Gainesville, FL 32611-0500 (United States); Raj, Anshita [Eco-Auditing group, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226 001 (India)

    2009-08-15

    This study investigated the effects of arsenic on the in vitro activities of the enzymes (nitrate reductase and nitrite reductase) involved in nitrate metabolism in the roots, rhizomes, and fronds of four-month old Pteris vittata (arsenic - hyperaccumulator) and Pteris ensiformis (non-arsenic--hyperaccumulator) plants. The arsenic treatments (0, 150, and 300 muM as sodium arsenate) in hydroponics had adverse effects on the root and frond dry weights, and this effect was more evident in P. ensiformis than in P. vittata. Nitrate reductase and nitrite reductase activities of arsenate-treated plants were reduced more in P. ensiformis than in P. vittata. This effect was accompanied by similar decreases in tissue NO{sub 3}{sup -} concentrations. Therefore, this decrease is interpreted as being indirect, i.e., the consequence of the reduced NO{sub 3}{sup -} uptake and translocation in the plants. The study shows the difference in the tolerance level of the two Pteris species with varying sensitivity to arsenic. - Arsenic reduced the activity of nitrate and nitrite reductase more in Pteris ensiformis than Pteris vittata.

  2. Folate deficiency enhances arsenic effects on expression of genes involved in epidermal differentiation in transgenic K6/ODC mouse skin

    International Nuclear Information System (INIS)

    Nelson, Gail M.; Ahlborn, Gene J.; Delker, Don A.; Kitchin, Kirk T.; O'Brien, Thomas G.; Chen Yan; Kohan, Michael J.; Roop, Barbara C.; Ward, William O.; Allen, James W.

    2007-01-01

    Chronic arsenic exposure in humans is associated with cancers of the skin, lung, bladder and other tissues. There is evidence that folate deficiency may increase susceptibility to arsenic effects, including skin lesions. K6/ODC mice develop skin tumors when exposed to 10 ppm sodium arsenite for 5 months. In the current study, K6/ODC mice maintained on either a folate deficient or folate sufficient diet were exposed to 0, 1, or 10 ppm sodium arsenite in the drinking water for 30 days. Total RNA was isolated from skin samples and gene expression analyzed using Affymetrix Mouse 430 2.0 GeneChips. Data from 24 samples, with 4 mice in each of the 6 treatment groups, were RMA normalized and analyzed by two-way ANOVA using GeneSpring TM . Top gene ontology (GO) categories for genes responding significantly to both arsenic treatment and folate deficiency include nucleotide metabolism and cell organization and biogenesis. For many of these genes, folate deficiency magnifies the response to arsenic treatment. In particular, expression of markers of epidermal differentiation, e.g., loricrin, small proline rich proteins and involucrin, was significantly reduced by arsenic in the folate sufficient animals, and reduced further or at a lower arsenic dose in the folate deficient animals. In addition, expression of a number of epidermal cell growth/proliferation genes and cellular movement genes was altered. These results indicate that arsenic disrupts the normal balance of cell proliferation and differentiation, and that folate deficiency exacerbates these effects, consistent with the view that folate deficiency is a nutritional susceptibility factor for arsenic-induced skin tumorigenesis

  3. Effect of chemophytostabilization practices on arbuscular mycorrhiza colonization of Deschampsia cespitosa ecotype Warynski at different soil depths

    International Nuclear Information System (INIS)

    Gucwa-Przepiora, Ewa; Malkowski, Eugeniusz; Sas-Nowosielska, Aleksandra; Kucharski, Rafal; Krzyzak, Jacek; Kita, Andrzej; Roemkens, Paul F.A.M.

    2007-01-01

    The effects of chemophytostabilization practices on arbuscular mycorrhiza (AM) of Deschampsia cespitosa roots at different depths in soils highly contaminated with heavy metals were studied in field trials. Mycorrhizal parameters, including frequency of mycorrhization, intensity of root cortex colonization and arbuscule abundance were studied. Correlations between concentration of bioavailable Cd, Zn, Pb and Cu in soil and mycorrhizal parameters were estimated. An increase in AM colonization with increasing soil depth was observed in soils with spontaneously growing D. cespitosa. A positive effect of chemophytostabilization amendments (calcium phosphate, lignite) on AM colonization was found in the soil layers to which the amendments were applied. Negative correlation coefficients between mycorrhizal parameters and concentration of bioavailable Cd and Zn in soil were obtained. Our results demonstrated that chemophytostabilization practices enhance AM colonization in D. cespitosa roots, even in soils fertilized with high rates of phosphorus. - Addition of phosphorus and lignite in chemophytostabilization increased arbuscular mycorrhizal colonization of Deschampsia cespitosa roots

  4. Arsenic Exposure, Arsenic Metabolism, and Incident Diabetes in the Strong Heart Study

    Science.gov (United States)

    Howard, Barbara V.; Umans, Jason G.; Gribble, Matthew O.; Best, Lyle G.; Francesconi, Kevin A.; Goessler, Walter; Lee, Elisa; Guallar, Eliseo; Navas-Acien, Ana

    2015-01-01

    OBJECTIVE Little is known about arsenic metabolism in diabetes development. We investigated the prospective associations of low-moderate arsenic exposure and arsenic metabolism with diabetes incidence in the Strong Heart Study. RESEARCH DESIGN AND METHODS A total of 1,694 diabetes-free participants aged 45–75 years were recruited in 1989–1991 and followed through 1998–1999. We used the proportions of urine inorganic arsenic (iAs), monomethylarsonate (MMA), and dimethylarsinate (DMA) over their sum (expressed as iAs%, MMA%, and DMA%) as the biomarkers of arsenic metabolism. Diabetes was defined as fasting glucose ≥126 mg/dL, 2-h glucose ≥200 mg/dL, self-reported diabetes history, or self-reported use of antidiabetic medications. RESULTS Over 11,263.2 person-years of follow-up, 396 participants developed diabetes. Using the leave-one-out approach to model the dynamics of arsenic metabolism, we found that lower MMA% was associated with higher diabetes incidence. The hazard ratios (95% CI) of diabetes incidence for a 5% increase in MMA% were 0.77 (0.63–0.93) and 0.82 (0.73–0.92) when iAs% and DMA%, respectively, were left out of the model. DMA% was associated with higher diabetes incidence only when MMA% decreased (left out of the model) but not when iAs% decreased. iAs% was also associated with higher diabetes incidence when MMA% decreased. The association between MMA% and diabetes incidence was similar by age, sex, study site, obesity, and urine iAs concentrations. CONCLUSIONS Arsenic metabolism, particularly lower MMA%, was prospectively associated with increased incidence of diabetes. Research is needed to evaluate whether arsenic metabolism is related to diabetes incidence per se or through its close connections with one-carbon metabolism. PMID:25583752

  5. Acute and chronic arsenic toxicity

    OpenAIRE

    Ratnaike, R

    2003-01-01

    Arsenic toxicity is a global health problem affecting many millions of people. Contamination is caused by arsenic from natural geological sources leaching into aquifers, contaminating drinking water and may also occur from mining and other industrial processes. Arsenic is present as a contaminant in many traditional remedies. Arsenic trioxide is now used to treat acute promyelocytic leukaemia. Absorption occurs predominantly from ingestion from the small intestine, though minimal absorption o...

  6. Mycorrhization helper bacteria: a case of specificity for altering ectomycorrhiza architecture but not ectomycorrhiza formation.

    Science.gov (United States)

    Aspray, Thomas J; Frey-Klett, Pascale; Jones, Julie E; Whipps, John M; Garbaye, Jean; Bending, Gary D

    2006-11-01

    Mycorrhization helper bacteria (MHB), isolated from phylogenetically distinct ectomycorrhizal symbioses involving Lactarius rufus, Laccaria bicolor or Suillus luteus, were tested for fungus specificity to enhance L. rufus-Pinus sylvestris or L. bicolor-P. sylvestris mycorrhiza formation. As MHB isolated from the L. rufus and S. luteus mycorrhiza were originally characterised using a microcosm system, we assessed their ability to enhance mycorrhiza formation in a glasshouse system in order to determine the extent to which MHB are system-specific. Paenibacillus sp. EJP73, an MHB for L. rufus in the microcosm, significantly enhanced L. bicolor mycorrhiza formation in the glasshouse, demonstrating that the MHB effect of this bacterium is neither fungus-specific nor limited to the original experimental system. Although the five MHB strains studied were unable to significantly enhance L. rufus mycorrhiza formation, two of them did have a significant effect on dichotomous short root branching by L. rufus. The effect was specific to Paenibacillus sp. EJP73 and Burkholderia sp. EJP67, the two strains isolated from L. rufus mycorrhiza, and was not associated with auxin production. Altered mycorrhiza architecture rather than absolute number of mycorrhizal roots may be an important previously overlooked parameter for defining MHB effects.

  7. Solar oxidation and removal of arsenic--Key parameters for continuous flow applications.

    Science.gov (United States)

    Gill, L W; O'Farrell, C

    2015-12-01

    Solar oxidation to remove arsenic from water has previously been investigated as a batch process. This research has investigated the kinetic parameters for the design of a continuous flow solar reactor to remove arsenic from contaminated groundwater supplies. Continuous flow recirculated batch experiments were carried out under artificial UV light to investigate the effect of different parameters on arsenic removal efficiency. Inlet water arsenic concentrations of up to 1000 μg/L were reduced to below 10 μg/L requiring 12 mg/L iron after receiving 12 kJUV/L radiation. Citrate however was somewhat surprisingly found to promote a detrimental effect on the removal process in the continuous flow reactor studies which is contrary to results found in batch scale tests. The impact of other typical water groundwater quality parameters (phosphate and silica) on the process due to their competition with arsenic for photooxidation products revealed a much higher sensitivity to phosphate ions compared to silicate. Other results showed no benefit from the addition of TiO2 photocatalyst but enhanced arsenic removal at higher temperatures up to 40 °C. Overall, these results have indicated the kinetic envelope from which a continuous flow SORAS single pass system could be more confidently designed for a full-scale community groundwater application at a village level. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Arsenic metabolism efficiency has a causal role in arsenic toxicity: Mendelian randomization and gene-environment interaction.

    Science.gov (United States)

    Pierce, Brandon L; Tong, Lin; Argos, Maria; Gao, Jianjun; Farzana, Jasmine; Roy, Shantanu; Paul-Brutus, Rachelle; Rahaman, Ronald; Rakibuz-Zaman, Muhammad; Parvez, Faruque; Ahmed, Alauddin; Quasem, Iftekhar; Hore, Samar K; Alam, Shafiul; Islam, Tariqul; Harjes, Judith; Sarwar, Golam; Slavkovich, Vesna; Gamble, Mary V; Chen, Yu; Yunus, Mohammad; Rahman, Mahfuzar; Baron, John A; Graziano, Joseph H; Ahsan, Habibul

    2013-12-01

    Arsenic exposure through drinking water is a serious global health issue. Observational studies suggest that individuals who metabolize arsenic efficiently are at lower risk for toxicities such as arsenical skin lesions. Using two single nucleotide polymorphisms(SNPs) in the 10q24.32 region (near AS3MT) that show independent associations with metabolism efficiency, Mendelian randomization can be used to assess whether the association between metabolism efficiency and skin lesions is likely to be causal. Using data on 2060 arsenic-exposed Bangladeshi individuals, we estimated associations for two 10q24.32 SNPs with relative concentrations of three urinary arsenic species (representing metabolism efficiency): inorganic arsenic (iAs), monomethylarsonic acid(MMA) and dimethylarsinic acid (DMA). SNP-based predictions of iAs%, MMA% and DMA% were tested for association with skin lesion status among 2483 cases and 2857 controls. Causal odds ratios for skin lesions were 0.90 (95% confidence interval[CI]: 0.87, 0.95), 1.19 (CI: 1.10, 1.28) and 1.23 (CI: 1.12, 1.36)for a one standard deviation increase in DMA%, MMA% and iAs%,respectively. We demonstrated genotype-arsenic interaction, with metabolism-related variants showing stronger associations with skin lesion risk among individuals with high arsenic exposure (synergy index: 1.37; CI: 1.11, 1.62). We provide strong evidence for a causal relationship between arsenic metabolism efficiency and skin lesion risk. Mendelian randomization can be used to assess the causal role of arsenic exposure and metabolism in a wide array of health conditions.exposure and metabolism in a wide array of health conditions.Developing interventions that increase arsenic metabolism efficiency are likely to reduce the impact of arsenic exposure on health.

  9. Health Effects of Chronic Arsenic Exposure

    Directory of Open Access Journals (Sweden)

    Young-Seoub Hong

    2014-09-01

    Full Text Available Arsenic is a unique element with distinct physical characteristics and toxicity whose importance in public health is well recognized. The toxicity of arsenic varies across its different forms. While the carcinogenicity of arsenic has been confirmed, the mechanisms behind the diseases occurring after acute or chronic exposure to arsenic are not well understood. Inorganic arsenic has been confirmed as a human carcinogen that can induce skin, lung, and bladder cancer. There are also reports of its significant association to liver, prostate, and bladder cancer. Recent studies have also suggested a relationship with diabetes, neurological effects, cardiac disorders, and reproductive organs, but further studies are required to confirm these associations. The majority of research to date has examined cancer incidence after a high exposure to high concentrations of arsenic. However, numerous studies have reported various health effects caused by chronic exposure to low concentrations of arsenic. An assessment of the health effects to arsenic exposure has never been performed in the South Korean population; thus, objective estimates of exposure levels are needed. Data should be collected on the biological exposure level for the total arsenic concentration, and individual arsenic concentration by species. In South Korea, we believe that biological exposure assessment should be the first step, followed by regular health effect assessments.

  10. Sequestration of arsenic in ombrotrophic peatlands

    Science.gov (United States)

    Rothwell, James; Hudson-Edwards, Karen; Taylor, Kevin; Polya, David; Evans, Martin; Allott, Tim

    2014-05-01

    Peatlands can be important stores of arsenic but we are lacking spectroscopic evidence of the sequestration pathways of this toxic metalloid in peatland environments. This study reports on the solid-phase speciation of anthropogenically-derived arsenic in atmospherically contaminated peat from the Peak District National Park (UK). Surface and sub-surface peat samples were analysed by synchrotron X-ray absorption spectroscopy on B18 beamline at Diamond Light Source (UK). The results suggest that there are contrasting arsenic sequestration mechanisms in the peat. The bulk arsenic speciation results, in combination with strong arsenic-iron correlations at the surface, suggest that iron (hydr)oxides are key phases for the immobilisation of arsenic at the peat surface. In contrast, the deeper peat samples are dominated by arsenic sulphides (arsenopyrite, realgar and orpiment). Given that these peats receive inputs solely from the atmosphere, the presence of these sulphide phases suggests an in-situ authigenic formation. Redox oscillations in the peat due to a fluctuating water table and an abundant store of legacy sulphur from historic acid rain inputs may favour the precipitation of arsenic sequestering sulphides in sub-surface horizons. Oxidation-induced loss of these arsenic sequestering sulphur species by water table drawdown has important implications for the mobility of arsenic and the quality of waters draining peatlands.

  11. Arsenic speciation in hair and nails of acute promyelocytic leukemia (APL) patients undergoing arsenic trioxide treatment.

    Science.gov (United States)

    Chen, Baowei; Cao, Fenglin; Lu, Xiufen; Shen, Shengwen; Zhou, Jin; Le, X Chris

    2018-07-01

    Arsenic in hair and nails has been used to assess chronic exposure of humans to environmental arsenic. However, it remains to be seen whether it is appropriate to evaluate acute exposure to sub-lethal doses of arsenic typically used in therapeutics. In this study, hair, fingernail and toenail samples were collected from nine acute promyelocytic leukemia (APL) patients who were administered intravenously the daily dose of 10 mg arsenic trioxide (7.5 mg arsenic) for up to 54 days. These hair and nail samples were analyzed for arsenic species using high performance liquid chromatography separation and inductively coupled plasma mass spectrometry detection (HPLC-ICPMS). Inorganic arsenite was the predominant form among water-extractable arsenicals. Dimethylarsinic acid (DMA V ), monomethylarsonic acid (MMA V ), monomethylarsonous acid (MMA III ), monomethylmonothioarsonic acid (MMMTA V ), and dimethylmonothioarsinic acid (DMMTA V ) were also detected in both hair and nail samples. This is the first report of the detection of MMA III and MMMTA V as metabolites of arsenic in hair and nails of APL patients. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Use of Endophytic and Rhizosphere Bacteria To Improve Phytoremediation of Arsenic-Contaminated Industrial Soils by Autochthonous Betula celtiberica.

    Science.gov (United States)

    Mesa, Victoria; Navazas, Alejandro; González-Gil, Ricardo; González, Aida; Weyens, Nele; Lauga, Béatrice; Gallego, Jose Luis R; Sánchez, Jesús; Peláez, Ana Isabel

    2017-04-15

    The aim of this study was to investigate the potential of indigenous arsenic-tolerant bacteria to enhance arsenic phytoremediation by the autochthonous pseudometallophyte Betula celtiberica The first goal was to perform an initial analysis of the entire rhizosphere and endophytic bacterial communities of the above-named accumulator plant, including the cultivable bacterial species. B. celtiberica 's microbiome was dominated by taxa related to Flavobacteriales , Burkholderiales , and Pseudomonadales , especially the Pseudomonas and Flavobacterium genera. A total of 54 cultivable rhizobacteria and 41 root endophytes, mainly affiliated with the phyla Proteobacteria , Bacteroidetes , Firmicutes , and Actinobacteria , were isolated and characterized with respect to several potentially useful features for metal plant accumulation, such as the ability to promote plant growth, metal chelation, and/or mitigation of heavy-metal stress. Seven bacterial isolates were further selected and tested for in vitro accumulation of arsenic in plants; four of them were finally assayed in field-scale bioaugmentation experiments. The exposure to arsenic in vitro caused an increase in the total nonprotein thiol compound content in roots, suggesting a detoxification mechanism through phytochelatin complexation. In the contaminated field, the siderophore and indole-3-acetic acid producers of the endophytic bacterial consortium enhanced arsenic accumulation in the leaves and roots of Betula celtiberica , whereas the rhizosphere isolate Ensifer adhaerens strain 91R mainly promoted plant growth. Field experimentation showed that additional factors, such as soil arsenic content and pH, influenced arsenic uptake in the plant, attesting to the relevance of field conditions in the success of phytoextraction strategies. IMPORTANCE Microorganisms and plants have developed several ways of dealing with arsenic, allowing them to resist and metabolize this metalloid. These properties form the basis of

  13. The characterization of novel mycorrhiza-specific phosphate transporters from ¤Lycopersicon esculentum¤ and ¤Solanum tuberosum¤ uncovers functional redundancy in symbiotic phosphate transport in solanaceous species

    DEFF Research Database (Denmark)

    Nagy, F.; Karandashov, V.; Chague, W.

    2005-01-01

    , is the transfer of phosphate (Pi) from the AM fungus to the plant, facilitated by plasma membrane-spanning Pi transporter proteins. The first mycorrhiza-specific plant Pi transporter to be identified, was StPT3 from potato [Nature 414 (2004) 462]. Here, we describe novel Pi transporters from the solanaceous...... species tomato, LePT4, and its orthologue StPT4 from potato, both being members of the Pht1 family of plant Pi transporters. Phylogenetic tree analysis demonstrates clustering of both LePT4 and StPT4 with the mycorrhiza-specific Pi transporter from Medicago truncatula [Plant Cell, 14 (2002) 2413] and rice......Solanaceous species are among the >200 000 plant species worldwide forming a mycorrhiza, that is, a root living in symbiosis with soil-borne arbuscular-mycorrhizal (AM) fungi. An important parameter of this symbiosis, which is vital for ecosystem productivity, agriculture, and horticulture...

  14. Mouse arsenic (+3 oxidation state) methyltransferase genotype affects metabolism and tissue dosimetry of arsenicals after arsenite administration in drinking water.

    Science.gov (United States)

    Chen, Baowei; Arnold, Lora L; Cohen, Samuel M; Thomas, David J; Le, X Chris

    2011-12-01

    Arsenic (+3 oxidation state) methyltransferase (As3mt) catalyzes methylation of inorganic arsenic (iAs) producing a number of methylated arsenic metabolites. Although methylation has been commonly considered a pathway for detoxification of arsenic, some highly reactive methylated arsenicals may contribute to toxicity associated with exposure to inorganic arsenic. Here, adult female wild-type (WT) C57BL/6 mice and female As3mt knockout (KO) mice received drinking water that contained 1, 10, or 25 ppm (mg/l) of arsenite for 33 days and blood, liver, kidney, and lung were taken for arsenic speciation. Genotype markedly affected concentrations of arsenicals in tissues. Summed concentrations of arsenicals in plasma were higher in WT than in KO mice; in red blood cells, summed concentrations of arsenicals were higher in KO than in WT mice. In liver, kidney, and lung, summed concentrations of arsenicals were greater in KO than in WT mice. Although capacity for arsenic methylation is much reduced in KO mice, some mono-, di-, and tri-methylated arsenicals were found in tissues of KO mice, likely reflecting the activity of other tissue methyltransferases or preabsorptive metabolism by the microbiota of the gastrointestinal tract. These results show that the genotype for arsenic methylation determines the phenotypes of arsenic retention and distribution and affects the dose- and organ-dependent toxicity associated with exposure to inorganic arsenic.

  15. Antifungal genes expressed in transgenic pea (Pisum sativum L.) do not affect root colonization of arbuscular mycorrhizae fungi.

    Science.gov (United States)

    Kahlon, Jagroop Gill; Jacobsen, Hans-Jörg; Cahill, James F; Hall, Linda M

    2017-10-01

    Genetically modified crops have raised concerns about unintended consequences on non-target organisms including beneficial soil associates. Pea transformed with four antifungal genes 1-3 β glucanase, endochitinase, polygalacturonase-inhibiting proteins, and stilbene synthase is currently under field-testing for efficacy against fungal diseases in Canada. Transgenes had lower expression in the roots than leaves in greenhouse experiment. To determine the impact of disease-tolerant pea or gene products on colonization by non-target arbuscular mycorrhizae and nodulation by rhizobium, a field trial was established. Transgene insertion, as single gene or stacked genes, did not alter root colonization by arbuscular mycorrhiza fungus (AMF) or root nodulation by rhizobium inoculation in the field. We found no effect of transgenes on the plant growth and performance although, having a dual inoculant with both AMF and rhizobium yielded higher fresh weight shoot-to-root ratio in all the lines tested. This initial risk assessment of transgenic peas expressing antifungal genes showed no deleterious effect on non-target organisms.

  16. Neutron activation analysis of arsenic in Greece

    International Nuclear Information System (INIS)

    Grimanis, A.P.

    1989-01-01

    Arsenic is considered a toxic trace element for plant, animal, and human organisms. Arsenic and certain arsenic compounds have been listed as carcinogens by the U.S. Environmental Protection Agency. Arsenic is emitted in appreciable quantities into the atmosphere by coal combustion and the production of cement. Arsenic enters the aquatic environment through industrial activities such as smelting of metallic ores, metallurgical glassware, and ceramics as well as insecticide production and use. Neutron activation analysis (NAA) is a very sensitive, precise, and accurate method for determining arsenic. This paper is a review of research studies of arsenic in the Greek environment by NAA performed at our radioanalytical laboratory. The objectives of these studies were (a) to determine levels of arsenic concentrations in environmental materials, (b) to pinpoint arsenic pollution sources and estimate the extent of arsenic pollution, and (c) to find out whether edible marine organisms from the gulfs of Greece receiving domestic, industrial, and agricultural wastes have elevated concentrations of arsenic in their tissues that could render them dangerous for human consumption

  17. Determinants and Consequences of Arsenic Metabolism Efficiency among 4,794 Individuals: Demographics, Lifestyle, Genetics, and Toxicity.

    Science.gov (United States)

    Jansen, Rick J; Argos, Maria; Tong, Lin; Li, Jiabei; Rakibuz-Zaman, Muhammad; Islam, Md Tariqul; Slavkovich, Vesna; Ahmed, Alauddin; Navas-Acien, Ana; Parvez, Faruque; Chen, Yu; Gamble, Mary V; Graziano, Joseph H; Pierce, Brandon L; Ahsan, Habibul

    2016-02-01

    Exposure to inorganic arsenic (iAs), a class I carcinogen, affects several hundred million people worldwide. Once absorbed, iAs is converted to monomethylated (MMA) and then dimethylated forms (DMA), with methylation facilitating urinary excretion. The abundance of each species in urine relative to their sum (iAs%, MMA%, and DMA%) varies across individuals, reflecting differences in arsenic metabolism capacity. The association of arsenic metabolism phenotypes with participant characteristics and arsenical skin lesions was characterized among 4,794 participants in the Health Effects of Arsenic Longitudinal Study (Araihazar, Bangladesh). Metabolism phenotypes include those obtained from principal component (PC) analysis of arsenic species. Two independent PCs were identified: PC1 appears to represent capacity to produce DMA (second methylation step), and PC2 appears to represent capacity to convert iAs to MMA (first methylation step). PC1 was positively associated (P 4.32/AS3MT region polymorphisms were strongly associated with PC1, but not PC2. Patterns of association for most variables were similar for PC1 and DMA%, and for PC2 and MMA% with the exception of arsenic exposure and SNP associations. Two distinct arsenic metabolism phenotypes show unique associations with age, sex, BMI, 10q24.32 polymorphisms, and skin lesions. This work enhances our understanding of arsenic metabolism kinetics and toxicity risk profiles. ©2015 American Association for Cancer Research.

  18. Arsenic and Antimony Transporters in Eukaryotes

    Directory of Open Access Journals (Sweden)

    Ewa Maciaszczyk-Dziubinska

    2012-03-01

    Full Text Available Arsenic and antimony are toxic metalloids, naturally present in the environment and all organisms have developed pathways for their detoxification. The most effective metalloid tolerance systems in eukaryotes include downregulation of metalloid uptake, efflux out of the cell, and complexation with phytochelatin or glutathione followed by sequestration into the vacuole. Understanding of arsenic and antimony transport system is of high importance due to the increasing usage of arsenic-based drugs in the treatment of certain types of cancer and diseases caused by protozoan parasites as well as for the development of bio- and phytoremediation strategies for metalloid polluted areas. However, in contrast to prokaryotes, the knowledge about specific transporters of arsenic and antimony and the mechanisms of metalloid transport in eukaryotes has been very limited for a long time. Here, we review the recent advances in understanding of arsenic and antimony transport pathways in eukaryotes, including a dual role of aquaglyceroporins in uptake and efflux of metalloids, elucidation of arsenic transport mechanism by the yeast Acr3 transporter and its role in arsenic hyperaccumulation in ferns, identification of vacuolar transporters of arsenic-phytochelatin complexes in plants and forms of arsenic substrates recognized by mammalian ABC transporters.

  19. Arsenic and Antimony Transporters in Eukaryotes

    Science.gov (United States)

    Maciaszczyk-Dziubinska, Ewa; Wawrzycka, Donata; Wysocki, Robert

    2012-01-01

    Arsenic and antimony are toxic metalloids, naturally present in the environment and all organisms have developed pathways for their detoxification. The most effective metalloid tolerance systems in eukaryotes include downregulation of metalloid uptake, efflux out of the cell, and complexation with phytochelatin or glutathione followed by sequestration into the vacuole. Understanding of arsenic and antimony transport system is of high importance due to the increasing usage of arsenic-based drugs in the treatment of certain types of cancer and diseases caused by protozoan parasites as well as for the development of bio- and phytoremediation strategies for metalloid polluted areas. However, in contrast to prokaryotes, the knowledge about specific transporters of arsenic and antimony and the mechanisms of metalloid transport in eukaryotes has been very limited for a long time. Here, we review the recent advances in understanding of arsenic and antimony transport pathways in eukaryotes, including a dual role of aquaglyceroporins in uptake and efflux of metalloids, elucidation of arsenic transport mechanism by the yeast Acr3 transporter and its role in arsenic hyperaccumulation in ferns, identification of vacuolar transporters of arsenic-phytochelatin complexes in plants and forms of arsenic substrates recognized by mammalian ABC transporters. PMID:22489166

  20. MDI Biological Laboratory Arsenic Summit: Approaches to Limiting Human Exposure to Arsenic

    OpenAIRE

    Stanton, Bruce A.

    2015-01-01

    This report is the outcome of the meeting: “Environmental and Human Health Consequences of Arsenic”, held at the MDI Biological Laboratory in Salisbury Cove, Maine, August 13–15, 2014. Human exposure to arsenic represents a significant health problem worldwide that requires immediate attention according to the World Health Organization (WHO). One billion people are exposed to arsenic in food and more than 200 million people ingest arsenic via drinking water at concentrations greater than inte...

  1. Relationship between arsenic and selenium in workers occupationally exposed to inorganic arsenic.

    Science.gov (United States)

    Janasik, Beata; Zawisza, Anna; Malachowska, Beata; Fendler, Wojciech; Stanislawska, Magdalena; Kuras, Renata; Wasowicz, Wojciech

    2017-07-01

    The interaction between arsenic (As) and selenium (Se) has been one of the most extensively studied. The antagonism between As and Se suggests that low Se status plays an important role in aggravating arsenic toxicity in diseases development. The objective of this study was to assess the Se contents in biological samples of inorganic As exposed workers (n=61) and in non-exposed subjects (n=52). Median (Me) total arsenic concentration in urine of exposed workers was 21.83μg/g creat. (interquartile range (IQR) 15.49-39.77) and was significantly higher than in the control group - (Me 3.75μg/g creat. (IQR 2.52-9.26), piAs+MMA+DMA) was significantly associated with the high total selenium urine excretion (B=0.14 (95%CI (confidence interval) 0.05-0.23)). Combination of both arsenic and selenium status to assess the risk of arsenic-induced diseases requires more studies with regard to both the analysis of speciation, genetics and the influence of factors such as nutritional status. Copyright © 2017 Elsevier GmbH. All rights reserved.

  2. Ameliorative effects of selenium on arsenic-induced cytotoxicity in PC12 cells via modulating autophagy/apoptosis.

    Science.gov (United States)

    Rahman, Md Mostafizur; Uson-Lopez, Rachael A; Sikder, Md Tajuddin; Tan, Gongxun; Hosokawa, Toshiyuki; Saito, Takeshi; Kurasaki, Masaaki

    2018-04-01

    Arsenic is well known toxicant responsible for human diseases including cancers. On the other hand, selenium is an essential trace element with significant chemopreventive effects, anticancer potentials and antioxidant properties. Although previous studies have reported antagonism/synergism between arsenic and selenium in biological systems, the biomolecular mechanism/s is still inconclusive. Therefore, to elucidate the molecular phenomena in cellular level, we hypothesized that co-exposure of selenium with arsenic may have suppressive effects on arsenic-induced cytotoxicity. We found that selenium in co-exposure with arsenic increases cell viability, and suppresses oxidative stress induced by arsenic in PC12 cells. Consequently, DNA fragmentation due to arsenic exposure was also reduced by arsenic and selenium co-exposure. Furthermore, western blot analyses revealed that simultaneous exposure of both metals significantly inhibited autophagy which further suppressed apoptosis through positively regulation of key proteins; p-mTOR, p-Akt, p-Foxo1A, p62, and expression of ubiquitin, Bax, Bcl2, NFкB, and caspases 3 and 9, although those are negatively regulated by arsenic. In addition, reverse transcriptase PCR analysis confirmed the involvement of caspase cascade in cell death process induced by arsenic and subsequent inhibition by co-exposure of selenium with arsenic. The cellular accumulation study of arsenic in presence/absence of selenium via inductively coupled plasma mass spectrometry confirmed that selenium effectively retarded the uptake of arsenic in PC12 cells. Finally, these findings imply that selenium is capable to modulate arsenic-induced intrinsic apoptosis pathway via enhancement of mTOR/Akt autophagy signaling pathway through employing antioxidant potentials and through inhibiting the cellular accumulation of arsenic in PC12 cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Arsenic K-edge X-ray absorption near-edge spectroscopy to determine oxidation states of arsenic of a coastal aquifer–aquitard system

    International Nuclear Information System (INIS)

    Wang, Ya; Jiao, Jiu Jimmy; Zhu, Sanyuan; Li, Yiliang

    2013-01-01

    Determination of oxidation states of solid-phase arsenic in bulk sediments is a valuable step in the evaluation of its bioavailability and environmental fate in deposits, but is difficult when the sediments have low arsenic contents and heterogeneous distribution of arsenic species. As K-edge X-ray absorption near-edge spectroscopy (XANES) was used to determine quantitatively the oxidation states of arsenic in sediments collected from different depths of boreholes in the Pearl River Delta, China, where the highest aquatic arsenic concentration is 161.4 μg/L, but the highest solid arsenic content only 39.6 mg/kg. The results demonstrated that XANES is efficient in determining arsenic oxidation states of the sediments with low arsenic contents and multiple arsenic species. The study on the high-resolution vertical variations of arsenic oxidation states also indicated that these states are influenced strongly by groundwater activities. With the help of geochemical data, solid arsenic speciation, toxicity and availability were further discussed. -- Highlights: •XANES is efficient in determining arsenic oxidation states of the bulk sediments. •Distribution of arsenic oxidation states is consistent with geochemical conditions. •Arsenic oxidation states are influenced strongly by groundwater activities. -- As K-edge X-ray absorption near-edge spectroscopy is efficient in determining arsenic oxidation states of the bulk sediments with low arsenic contents and heterogeneous distribution of arsenic species

  4. Effect of eutrophication on the distribution of arsenic species in eutrophic and mesotrophic lakes

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, H. [Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192 (Japan)], E-mail: hhiroshi@t.kanazawa-u.ac.jp; Rahman, M. Azizur; Matsuda, T.; Kitahara, T.; Maki, T.; Ueda, K. [Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192 (Japan)

    2009-02-01

    Effects of eutrophication on arsenic speciation were studied in eutrophic Lake Kiba and mesotrophic Lake Biwa, Japan. By combining hydride generation atomic absorption spectrometry with ultraviolet irradiation, inorganic, methyl and ultraviolet-labile fractions of arsenic were determined. In both Lakes, inorganic species (As(V + III)) dominated over other forms of arsenic all the year round. Most of methylarsenic fraction was dimethylarsinic acid (DMAA), and the concentration of monomethylarsonic acid (MMAA) was below the detection limit. Measurements of size-fractioned arsenic concentrations in water column indicate that most of the DMAA was distributed in truly dissolved fraction (< 10 kDa), while ultraviolet-labile fractions were distributed in particulate (> 0.45 {mu}m) and colloidal (10 kDa-0.45 {mu}m) fractions. Arsenic speciation in eutrophic Lake Kiba fluctuated greatly with season. The ultraviolet-labile fractions were observed with the increase of DMAA from May to October, and they disappeared with the decrease of DMAA in January. In mesotrophic Lake Biwa, the ultraviolet-labile fractions of arsenic were not influenced as much as those in eutrophic Lake Kiba. On the other hand DMAA concentration was higher in Lake Biwa compared to that in Lake Kiba. The results suggest that the biosynthesis of complex organoarsenicals was enhanced by eutrophication, and the arsenic speciation would be influenced by the balance of biological processes in natural waters.

  5. Voltammetric Study of Arsenic (III and Arsenic (V in Ground Water of Hajigonj and Kalkini in Bangladesh

    Directory of Open Access Journals (Sweden)

    Mohammad Arifur Rahman

    2008-06-01

    Full Text Available The speciation of arsenic in groundwater samples using Square Wave Anodic Stripping Voltammetry (SWASV, Differential Pulse Anodic Stripping Voltammetry (DPASV and Normal Pulse Anodic Stripping Voltammetry (NPASV are described. Good resolution of the species, arsenic (III and arsenic (V is achieved using SWASV. The reliability of the methods was checked by analyzing the total arsenic content of the samples by Hydride Generation Atomic Absorptioion Spectrophotometer and by analyzing prepared controlled laboratory standard solution. Since this technique is comparatively cheaper than other available techniques it could be a better analytical technique for arsenic speciation from water. In this study, the assessment of inorganic arsenic species in ground water of Kalkini (Madaripur and Hajigonj (Chandpur is reported. It shows that arsenic content in water in different locations is irregular. Most of the locations contain higher level of As(III than As(V. The highest concentration of arsenic is found in Anayetnagor (554.46 ± 0.07 mg/L of Kalkini and Raichar (562 ± 0.50 mg/L of Hajigonj. However, the level of total arsenic and As(III of most of the villages of the study areas are more than the WHO guideline value (50mg/L. Therefore a proper monitoring process should be evolved along with the development of methods to keep the water free from arsenic.

  6. Rapid arsenic(V)-reduction by fire in schwertmannite-rich soil enhances arsenic mobilisation

    DEFF Research Database (Denmark)

    Johnston, Scott G.; Bennett, William W.; Burton, Edward D.

    2018-01-01

    (III) formation (∼90%) within 5–10 min at 400–600 °C, followed by partial re-oxidation to As(V) thereafter. In contrast, heating As(V)-schwertmannite in the absence of soil-organic matter did not cause reduction of As(V) or Fe(III), nor form maghemite; thus highlighting the critical role of organic matter......Arsenic in acid sulfate soil (ASS) landscapes commonly associates with schwertmannite, a poorly crystalline Fe(III) mineral. Fires in ASS landscapes can thermally transform Fe(III) minerals to more crystalline phases, such as maghemite (γFe2O3). Although thermal genesis of maghemite requires...... and hematite at temperatures above 300–400 °C, with some transitory formation of magnetite, and electrons are readily transferred to both Fe(III) and As(V). As(V) reduction to As(III) is influenced by a combination of temperature, heating duration and carbon content and is significantly (P

  7. Arsenic removal by lime softening

    DEFF Research Database (Denmark)

    Kaosol, T.; Suksaroj, C.; Bregnhøj, Henrik

    2002-01-01

    This paper focuses on the study of arsenic removal for drinking water by lime softening. The initial arsenic (V) concentration was 500 and 1,000 ug/L in synthetic groundwater. The experiments were performed as batch tests with varying lime dosages and mixing time. For the synthetic groundwater......, arsenic (V) removal increased with increasing lime dosage and mixing time, as well as with the resulting pH. The residual arsenic (V) in all cases was lower than the WHO guideline of 10 ug/L at pH higher than 11.5. Kinetic of arsenic (V) removal can be described by a first-order equation as C1 = C0*e......^-k*t. The relation between the constant (k value) and increasing lime dosage was found to be linear, described by k = 0.0034 (Dlime). The results support a theory from the literature that the arsenic (V) was removed by precipitation af Ca3(AsO4)2. The results obtained in the present study suggest that lime...

  8. Incorporation of arsenic into gypsum: Relevant to arsenic removal and immobilization process in hydrometallurgical industry

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Danni; Yuan, Zidan [Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Wang, Shaofeng, E-mail: wangshaofeng@iae.ac.cn [Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Jia, Yongfeng, E-mail: yongfeng.jia@iae.ac.cn [Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Demopoulos, George P. [Department of Mining and Materials Engineering, McGill University, Montreal, QC H3A 2B2 (Canada)

    2015-12-30

    Highlights: • Quantitatively studied the incorporation of arsenic into the structure of gypsum. • Arsenic content in the solid increased with pH and initial arsenic concentration. • Calcium arsenate phase precipitated in addition to gypsum at higher pH values. • The structure of gypsum and its morphology was altered by the incorporated arsenate. • The incorporated arsenate formed sainfeldite-like local structure in gypsum. - Abstract: Gypsum precipitates as a major secondary mineral during the iron-arsenate coprecipitation process for the removal of arsenic from hydrometallurgical effluents. However, its role in the fixation of arsenic is still unknown. This work investigated the incorporation of arsenic into gypsum quantitatively during the crystallization process at various pHs and the initial arsenic concentrations. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray absorption near edge spectroscopy (XANES) and scanning electron microscopy (SEM) were employed to characterize the coprecipitated solids. The results showed that arsenate was measurably removed from solution during gypsum crystallization and the removal increased with increasing pH. At lower pH where the system was undersaturated with respect to calcium arsenate, arsenate ions were incorporated into gypsum structure, whereas at higher pH, calcium arsenate was formed and constituted the major arsenate bearing species in the precipitated solids. The findings may have important implications for arsenic speciation and stability of the hydrometallurgical solid wastes.

  9. Arsenic chemistry in soils and sediments

    Energy Technology Data Exchange (ETDEWEB)

    Fendorf, S.; Nico, P.; Kocar, B.D.; Masue, Y.; Tufano, K.J.

    2009-10-15

    Arsenic is a naturally occurring trace element that poses a threat to human and ecosystem health, particularly when incorporated into food or water supplies. The greatest risk imposed by arsenic to human health results from contamination of drinking water, for which the World Health Organization recommends a maximum limit of 10 {micro}g L{sup -1}. Continued ingestion of drinking water having hazardous levels of arsenic can lead to arsenicosis and cancers of the bladder, skin, lungs and kidneys. Unfortunately, arsenic tainted drinking waters are a global threat and presently having a devastating impact on human health within Asia. Nearly 100 million people, for example, are presently consuming drinking water having arsenic concentrations exceeding the World Health Organization's recommended limit (Ahmed et al., 2006). Arsenic contamination of the environment often results from human activities such as mining or pesticide application, but recently natural sources of arsenic have demonstrated a devastating impact on water quality. Arsenic becomes problematic from a health perspective principally when it partitions into the aqueous rather than the solid phase. Dissolved concentrations, and the resulting mobility, of arsenic within soils and sediments are the combined result of biogeochemical processes linked to hydrologic factors. Processes favoring the partitioning of As into the aqueous phase, potentially leading to hazardous concentrations, vary extensively but can broadly be grouped into four categories: (1) ion displacement, (2) desorption (or limited sorption) at pH values > 8.5, (3) reduction of arsenate to arsenite, and (4) mineral dissolution, particularly reductive dissolution of Fe and Mn (hydr)oxides. Although various processes may liberate arsenic from solids, a transition from aerobic to anaerobic conditions, and commensurate arsenic and iron/manganese reduction, appears to be a dominant, but not exclusive, means by which high concentrations of

  10. Understanding Arsenic Dynamics in Agronomic Systems to ...

    Science.gov (United States)

    This review is on arsenic in agronomic systems, and covers processes that influence the entry of arsenic into the human food supply. The scope is from sources of arsenic (natural and anthropogenic) in soils, biogeochemical and rhizosphere processes that control arsenic speciation and availability, through to mechanisms of uptake by crop plants and potential mitigation strategies. This review makes a case for taking steps to prevent or limit crop uptake of arsenic, wherever possible, and to work toward a long-term solution to the presence of arsenic in agronomic systems. The past two decades have seen important advances in our understanding of how biogeochemical and physiological processes influence human exposure to soil arsenic, and thus must now prompt an informed reconsideration and unification of regulations to protect the quality of agricultural and residential soils. Consumption of staple foods such as rice, beverages such as apple juice, or vegetables grown in historically arsenic-contaminated soils is now recognized as a tangible route of arsenic exposure that, in many cases, is more significant than exposure from drinking water. Understanding the sources of arsenic to crop plants and the factors that influence them is key to reducing exposure now and preventing exposure in future. In addition to the abundant natural sources of arsenic, there are a large number of industrial and agricultural sources of arsenic to the soil; from mining wastes, coal fly

  11. Arsenic: natural and anthropogenic

    National Research Council Canada - National Science Library

    Matschullat, Jörg; Deschamps, Eleonora

    2011-01-01

    .... Based on state-of-the-art investigations into the global arsenic cycle, the related human toxicology and available remediation technologies, it assesses arsenic in all the environmental compartments...

  12. Arsenic transport by zebrafish aquaglyceroporins

    Directory of Open Access Journals (Sweden)

    Landfear Scott M

    2009-11-01

    Full Text Available Abstract Background Arsenic is one of the most ubiquitous toxins and endangers the health of tens of millions of humans worldwide. It is a mainly a water-borne contaminant. Inorganic trivalent arsenic (AsIII is one of the major species that exists environmentally. The transport of AsIII has been studied in microbes, plants and mammals. Members of the aquaglyceroporin family have been shown to actively conduct AsIII and its organic metabolite, monomethylarsenite (MAsIII. However, the transport of AsIII and MAsIII in in any fish species has not been characterized. Results In this study, five members of the aquaglyceroporin family from zebrafish (Danio rerio were cloned, and their ability to transport water, glycerol, and trivalent arsenicals (AsIII and MAsIII and antimonite (SbIII was investigated. Genes for at least seven aquaglyceroporins have been annotated in the zebrafish genome project. Here, five genes which are close homologues to human AQP3, AQP9 and AQP10 were cloned from a zebrafish cDNA preparation. These genes were named aqp3, aqp3l, aqp9a, aqp9b and aqp10 according to their similarities to the corresponding human AQPs. Expression of aqp9a, aqp9b, aqp3, aqp3l and aqp10 in multiple zebrafish organs were examined by RT-PCR. Our results demonstrated that these aquaglyceroporins exhibited different tissue expression. They are all detected in more than one tissue. The ability of these five aquaglyceroporins to transport water, glycerol and the metalloids arsenic and antimony was examined following expression in oocytes from Xenopus leavis. Each of these channels showed substantial glycerol transport at equivalent rates. These aquaglyceroporins also facilitate uptake of inorganic AsIII, MAsIII and SbIII. Arsenic accumulation in fish larvae and in different tissues from adult zebrafish was studied following short-term arsenic exposure. The results showed that liver is the major organ of arsenic accumulation; other tissues such as gill, eye

  13. Determination of arsenic compounds in earthworms

    Energy Technology Data Exchange (ETDEWEB)

    Geiszinger, A.; Goessler, W.; Kuehnelt, D.; Kosmus, W. [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry; Francesconi, K. [Odense Univ. (Denmark). Inst. of Biology

    1998-08-01

    Earthworms and soil collected from six sites in Styria, Austria, were investigated for total arsenic concentrations by ICP-MS and for arsenic compounds by HPLC-ICP-MS. Total arsenic concentrations ranged from 3.2 to 17.9 mg/kg dry weight in the worms and from 5.0 to 79.7 mg/kg dry weight in the soil samples. There was no strict correlation between the total arsenic concentrations in the worms and soil. Arsenic compounds were extracted from soil and a freeze-dried earthworm sample with a methanol/water mixture (9:1, v/v). The extracts were evaporated to dryness, redissolved in water, and chromatographed on an anion- and a cation-exchange column. Arsenic compounds were identified by comparison of the retention times with known standards. Only traces of arsenic acid could be extracted from the soil with the methanol/water (9:1, v/v) mixture. The major arsenic compounds detected in the extracts of the earthworms were arsenous acid and arsenic acid. Arsenobetaine was present as a minor constituent, and traces of dimethylarsinic acid were also detected. Two dimethylarsinoyltribosides were also identified in the extracts by co-chromatography with standard compounds. This is the first report of the presence of dimethylarsinoylribosides in a terrestrial organism. Two other minor arsenic species were present in the extract, but their retention times did not match with the retention times of the available standards.

  14. Variability in human metabolism of arsenic

    International Nuclear Information System (INIS)

    Loffredo, C.A.; Aposhian, H.V.; Cebrian, M.E.; Yamauchi, Hiroshi; Silbergeld, E.K.

    2003-01-01

    Estimating the nature and extent of human cancer risks due to arsenic (As) in drinking water is currently of great concern, since millions of persons worldwide are exposed to arsenic, primarily through natural enrichment of drinking water drawn from deep wells. Humans metabolize and eliminate As through oxidative methylation and subsequent urinary excretion. While there is debate as to the role of methylation in activation/detoxification, variations in arsenic metabolism may affect individual risks of toxicity and carcinogenesis. Using data from three populations, from Mexico, China, and Chile, we have analyzed the distribution in urine of total arsenic and arsenic species (inorganic arsenic (InAs), monomethyl arsenic (MMA), and dimethyl arsenic (DMA). Data were analyzed in terms of the concentration of each species and by evaluating MMA:DMA and (MMA+DMA):InAs ratios. In all persons most urinary As was present as DMA. Male:female differences were discernible in both high- and low-exposure groups from all three populations, but the gender differences varied by populations. The data also indicated bimodal distributions in the ratios of DMA to InAs and to MMA. While the gene or genes responsible for arsenic methylation are still unknown, the results of our studies among the ethnic groups in this study are consistent with the presence of functional genetic polymorphisms in arsenic methylation leading to measurable differences in toxicity. This analysis highlights the need for continuing research on the health effects of As in humans using molecular epidemiologic methods

  15. Mathematical model insights into arsenic detoxification

    Directory of Open Access Journals (Sweden)

    Nijhout H Frederik

    2011-08-01

    Full Text Available Abstract Background Arsenic in drinking water, a major health hazard to millions of people in South and East Asia and in other parts of the world, is ingested primarily as trivalent inorganic arsenic (iAs, which then undergoes hepatic methylation to methylarsonic acid (MMAs and a second methylation to dimethylarsinic acid (DMAs. Although MMAs and DMAs are also known to be toxic, DMAs is more easily excreted in the urine and therefore methylation has generally been considered a detoxification pathway. A collaborative modeling project between epidemiologists, biologists, and mathematicians has the purpose of explaining existing data on methylation in human studies in Bangladesh and also testing, by mathematical modeling, effects of nutritional supplements that could increase As methylation. Methods We develop a whole body mathematical model of arsenic metabolism including arsenic absorption, storage, methylation, and excretion. The parameters for arsenic methylation in the liver were taken from the biochemical literature. The transport parameters between compartments are largely unknown, so we adjust them so that the model accurately predicts the urine excretion rates of time for the iAs, MMAs, and DMAs in single dose experiments on human subjects. Results We test the model by showing that, with no changes in parameters, it predicts accurately the time courses of urinary excretion in mutiple dose experiments conducted on human subjects. Our main purpose is to use the model to study and interpret the data on the effects of folate supplementation on arsenic methylation and excretion in clinical trials in Bangladesh. Folate supplementation of folate-deficient individuals resulted in a 14% decrease in arsenicals in the blood. This is confirmed by the model and the model predicts that arsenicals in the liver will decrease by 19% and arsenicals in other body stores by 26% in these same individuals. In addition, the model predicts that arsenic

  16. Enhanced arsenic removal from water by hierarchically porous CeO{sub 2}–ZrO{sub 2} nanospheres: Role of surface- and structure-dependent properties

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Weihong; Wang, Jing; Wang, Lei [Research Center for Biomimetic Functional Materials and Sensing Devices, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031 (China); Sheng, Guoping [Department of Chemistry, University of Science and Technology of China, Hefei 230026 (China); Liu, Jinhuai [Research Center for Biomimetic Functional Materials and Sensing Devices, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031 (China); Yu, Hanqing [Department of Chemistry, University of Science and Technology of China, Hefei 230026 (China); Huang, Xing-Jiu, E-mail: xingjiuhuang@iim.ac.cn [Research Center for Biomimetic Functional Materials and Sensing Devices, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031 (China)

    2013-09-15

    Highlights: • The CeO{sub 2}–ZrO{sub 2} hollow nanospheres had strong affinity and selectivity to arsenic. •The adsorbent showed excellent ability to remove arsenic at low concentrations. • The adsorption mechanism was investigated by FTIR and XPS. • The adsorbent showed potential application for drinking water treatment. -- Abstract: Arsenic contaminated natural water is commonly used as drinking water source in some districts of Asia. To meet the increasingly strict drinking water standards, exploration of efficient arsenic removal methods is highly desired. In this study, hierarchically porous CeO{sub 2}–ZrO{sub 2} nanospheres were synthesized, and their suitability as arsenic sorbents was examined. The CeO{sub 2}–ZrO{sub 2} hollow nanospheres showed an adsorption capacity of 27.1 and 9.2 mg g{sup −1} for As(V) and As(III), respectively, at an equilibrium arsenic concentration of 0.01 mg L{sup −1} (the standard for drinking water) under neutral conditions, indicating a high arsenic removal performance of the adsorbent at low arsenic concentrations. Such a great arsenic adsorption capacity was attributed to the high surface hydroxyl density and presence of hierarchically porous network in the hollow nanospheres. The analysis of Fourier transformed infrared spectra and X-ray photoelectron spectroscopy demonstrated that the adsorption of arsenic on the CeO{sub 2}–ZrO{sub 2} nanospheres was completed through the formation of a surface complex by substituting hydroxyl with arsenic species. In addition, the CeO{sub 2}–ZrO{sub 2} nanospheres were able to remove over 97% arsenic in real underground water with initial arsenic concentration of 0.376 mg L{sup −1} to meet the guideline limit of arsenic in drinking water regulated by the World Health Organization without any pre-treatment and/or pH adjustment.

  17. In situ treatment of arsenic contaminated groundwater by aquifer iron coating: Experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Xianjun, E-mail: xjxie@cug.edu.cn [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Wang, Yanxin, E-mail: yx.wang@cug.edu.cn [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Pi, Kunfu [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Liu, Chongxuan [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Pacific Northwest National Laboratory, Richland, WA 99354 (United States); Li, Junxia; Liu, Yaqing; Wang, Zhiqiang; Duan, Mengyu [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China)

    2015-09-15

    In situ arsenic removal from groundwater by an aquifer iron coating method has great potential to be a cost effective and simple groundwater remediation technology, especially in rural and remote areas where groundwater is used as the main water source for drinking. The in situ arsenic removal technology was first optimized by simulating arsenic removal in various quartz sand columns under anoxic conditions. The effectiveness was then evaluated in an actual high-arsenic groundwater environment. The arsenic removal mechanism by the coated iron oxide/hydroxide was investigated under different conditions using scanning electron microscopy (SEM)/X-ray absorption spectroscopy, electron probe microanalysis, and Fourier transformation infrared spectroscopy. Aquifer iron coating method was developed via a 4-step alternating injection of oxidant, iron salt and oxygen-free water. A continuous injection of 5.0 mmol/L FeSO{sub 4} and 2.5 mmol/L NaClO for 96 h can form a uniform goethite coating on the surface of quartz sand without causing clogging. At a flow rate of 7.2 mL/min of the injection reagents, arsenic (as Na{sub 2}HAsO{sub 4}) and tracer fluorescein sodium to pass through the iron-coated quartz sand column were approximately at 126 and 7 column pore volumes, respectively. The retardation factor of arsenic was 23.0, and the adsorption capacity was 0.11 mol As per mol Fe. In situ arsenic removal from groundwater in an aquifer was achieved by simultaneous injections of As(V) and Fe(II) reagents. Arsenic fixation resulted from a process of adsorption/co-precipitation with fine goethite particles by way of bidentate binuclear complexes. Therefore, the study results indicate that the high arsenic removal efficiency of the in situ aquifer iron coating technology likely resulted from the expanded specific surface area of the small goethite particles, which enhanced arsenic sorption capability and/or from co-precipitation of arsenic on the surface of goethite particles

  18. In situ treatment of arsenic contaminated groundwater by aquifer iron coating: Experimental study

    International Nuclear Information System (INIS)

    Xie, Xianjun; Wang, Yanxin; Pi, Kunfu; Liu, Chongxuan; Li, Junxia; Liu, Yaqing; Wang, Zhiqiang; Duan, Mengyu

    2015-01-01

    In situ arsenic removal from groundwater by an aquifer iron coating method has great potential to be a cost effective and simple groundwater remediation technology, especially in rural and remote areas where groundwater is used as the main water source for drinking. The in situ arsenic removal technology was first optimized by simulating arsenic removal in various quartz sand columns under anoxic conditions. The effectiveness was then evaluated in an actual high-arsenic groundwater environment. The arsenic removal mechanism by the coated iron oxide/hydroxide was investigated under different conditions using scanning electron microscopy (SEM)/X-ray absorption spectroscopy, electron probe microanalysis, and Fourier transformation infrared spectroscopy. Aquifer iron coating method was developed via a 4-step alternating injection of oxidant, iron salt and oxygen-free water. A continuous injection of 5.0 mmol/L FeSO 4 and 2.5 mmol/L NaClO for 96 h can form a uniform goethite coating on the surface of quartz sand without causing clogging. At a flow rate of 7.2 mL/min of the injection reagents, arsenic (as Na 2 HAsO 4 ) and tracer fluorescein sodium to pass through the iron-coated quartz sand column were approximately at 126 and 7 column pore volumes, respectively. The retardation factor of arsenic was 23.0, and the adsorption capacity was 0.11 mol As per mol Fe. In situ arsenic removal from groundwater in an aquifer was achieved by simultaneous injections of As(V) and Fe(II) reagents. Arsenic fixation resulted from a process of adsorption/co-precipitation with fine goethite particles by way of bidentate binuclear complexes. Therefore, the study results indicate that the high arsenic removal efficiency of the in situ aquifer iron coating technology likely resulted from the expanded specific surface area of the small goethite particles, which enhanced arsenic sorption capability and/or from co-precipitation of arsenic on the surface of goethite particles. - Highlights:

  19. Effects of mycorrhiza on growth and essential oil production in selected aromatic plants

    Directory of Open Access Journals (Sweden)

    Waed Tarraf

    2015-09-01

    Full Text Available Arbuscular mycorrhizal (AM symbiosis is widely investigated in aromatic herbs. Several studies have shown different effects on secondary metabolites, biomass production, as well as oil quantitative and qualitative aspects. The seeking to increase the yield of plants and their oils is an interesting topic in the world of medicinal and aromatic plant production. In tune with that, this study evaluated the effectiveness of two mycorrhiza fungi, Funneliformis mosseae (syn. Glomus mosseae and Septoglomus viscosum (syn. Glomus viscosum, on three species from Lamiaceae family: Salvia officinalis L., Origanum vulgare L., and Thymus vulgaris L. besides untreated control. It was found that the effect of symbiosis on growth was more favourable with S. viscosum than other AM fungus. The S. viscosum inoculation raised the yield of essential oil in oregano. Analysis of gas chromatography/mass spectrometry showed that manool obtained the highest abundance in leaf essential oil of inoculated sage; thymol was the major component whatever the treatment in thyme and lower relative content of carvacrol was reported with arbuscular mycorrhizal fungi inoculation in oregano. The results suggest the mycorrhizal inoculation as a promising technology in sustainable agricultural system to improve the plant productivity performance. Specific inocula are strategic to enhance the chemical profile of essential oils.

  20. Arsenic in the soils of Zimapan, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ongley, Lois K. [Oak Hill High School, P.O. Box 400, Sabattus, ME 04280 (United States)]. E-mail: loisongley@earthlink.net; Sherman, Leslie [Department of Chemistry, Washington College, 300 Washington Avenue, Chestertown, MD 21620 (United States); Armienta, Aurora [Instituto de Geofisica, UNAM, Mexico D.F. 04510 (Mexico); Concilio, Amy [Department of Earth, Ecological, and Environmental Sciences, University of Toledo, Toledo, OH 43606 (United States); Salinas, Carrie Ferguson [Department of Agronomy and Environmental Management, Louisiana State University, Baton Rouge, LA 70803 (United States)

    2007-02-15

    Arsenic concentrations of 73 soil samples collected in the semi-arid Zimapan Valley range from 4 to 14 700 mg As kg{sup -1}. Soil arsenic concentrations decrease with distance from mines and tailings and slag heaps and exceed 400 mg kg{sup -1} only within 500 m of these arsenic sources. Soil arsenic concentrations correlate positively with Cu, Pb, and Zn concentrations, suggesting a strong association with ore minerals known to exist in the region. Some As was associated with Fe and Mn oxyhydroxides, this association is less for contaminated than for uncontaminated samples. Very little As was found in the mobile water-soluble or exchangeable fractions. The soils are not arsenic contaminated at depths greater than 100 cm below the surface. Although much of the arsenic in the soils is associated with relatively immobile solid phases, this represents a long-term source of arsenic to the environment. -- Much of the arsenic is relatively immobile but presents long-term source of arsenic.

  1. Arsenic in the soils of Zimapan, Mexico

    International Nuclear Information System (INIS)

    Ongley, Lois K.; Sherman, Leslie; Armienta, Aurora; Concilio, Amy; Salinas, Carrie Ferguson

    2007-01-01

    Arsenic concentrations of 73 soil samples collected in the semi-arid Zimapan Valley range from 4 to 14 700 mg As kg -1 . Soil arsenic concentrations decrease with distance from mines and tailings and slag heaps and exceed 400 mg kg -1 only within 500 m of these arsenic sources. Soil arsenic concentrations correlate positively with Cu, Pb, and Zn concentrations, suggesting a strong association with ore minerals known to exist in the region. Some As was associated with Fe and Mn oxyhydroxides, this association is less for contaminated than for uncontaminated samples. Very little As was found in the mobile water-soluble or exchangeable fractions. The soils are not arsenic contaminated at depths greater than 100 cm below the surface. Although much of the arsenic in the soils is associated with relatively immobile solid phases, this represents a long-term source of arsenic to the environment. -- Much of the arsenic is relatively immobile but presents long-term source of arsenic

  2. Arsenic speciation and sorption in natural environments

    Science.gov (United States)

    Campbell, Kate M.; Nordstrom, D. Kirk

    2014-01-01

    Aqueous arsenic speciation, or the chemical forms in which arsenic exists in water, is a challenging, interesting, and complicated aspect of environmental arsenic geochemistry. Arsenic has the ability to form a wide range of chemical bonds with carbon, oxygen, hydrogen, and sulfur, resulting in a large variety of compounds that exhibit a host of chemical and biochemical properties. Besides the intriguing chemical diversity, arsenic also has the rare capacity to capture our imaginations in a way that few elements can duplicate: it invokes images of foul play that range from sinister to comedic (e.g., “inheritance powder” and arsenic-spiked elderberry wine). However, the emergence of serious large-scale human health problems from chronic arsenic exposure in drinking water has placed a high priority on understanding environmental arsenic mobility, toxicity, and bioavailability, and chemical speciation is key to these important questions. Ultimately, the purpose of arsenic speciation research is to predict future occurrences, mitigate contamination, and provide successful management of water resources.

  3. Natural re-establishment of vesicular-arbuscular mycorrhizae following stripmine reclamation in Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Allen, E.B.; Allen, M.F. (University of Wyoming, Laramie, WY (USA))

    1980-01-01

    The % root infection of {ital Agropyron smithii} and {ital A. intermedium} by vesicular-arbuscular mycorrhizae was measured and spoil spores were counted in six reclaimed stripmine sites in Wyoming. On 2- and 3-yr old sites % infection and spore counts were c. 50% or less than native prairie levels. Spore counts of a 3-yr old disked prairie site were not different from the undisturbed prairie level, but infection was significantly lower. Spore counts of the reclimed sites were not highly correlated with % root infection. Five of seven annuals which colonized the reclaimed and disked sites were non-mycorrhizal. 43 refs., 3 tabs.

  4. Investigating Arsenic Mobilization Mechanisms as well as Complexation Between Arsenic and Polysulfides Associated With a Bangladeshi Rice Paddy

    Science.gov (United States)

    Lin, T.; Kampalath, R.; Jay, J.

    2009-12-01

    The presence of arsenic in the groundwater has led to the largest environmental poisoning in history. Although it is a worldwide issue that affects numerous countries, including Taiwan, Bangladesh, India, China, Mexico, Peru, Australia, and the United States, the issue is of greatest concern in the West Bengal region. In the Ganges Delta, as many as 2 million people are diagnosed with arsenicosis each year. The World Health Organization (WHO) estimates 200,000 to 270,000 arsenic-induced cancer-related deaths in Bangladesh alone. More than 100 million people in the country consume groundwater that exceeds the WHO limit as 50% of the 8 million wells contain groundwater with more than 10 μg/L. Despite the tragic public health implications of this problem, we do not yet have a complete answer to the question of why dissolved arsenic concentrations are so high in the groundwater of the Ganges Delta. Since 1999, we have been intensively studying a field site in Munshiganj, Bangladesh with extremely high levels of arsenic in groundwater (up to 1.2 mg/L). Sediment cores were collected from two locations at the field site: 1) the rice paddy and 2) edge of a nearby irrigation pond. Recharge from irrigation ponds have recently been hypothesized to be an important site of arsenic mobilization. Recent work has proposed mineral dissolution under phosphorus-limited conditions as an important mechanism for arsenic mobilization. Using microcosms with paddy and pond sediment, we are comparing arsenic release via this mechanism with that resulting from reduction of iron hydroxides at our site. Concurrently, we are looking at enhanced solubility of As in the presence of polysulfides as the effects of elemental sulfur on As solubility have not been well researched. We hypothesize that the presence of elemental sulfur, and consequent formation of polysulfides, will substantially increase the solubility of orpiment in sulfidic water and that sorption of these complexes will

  5. Urinary arsenic speciation and its correlation with 8-OHdG in Chinese residents exposed to arsenic through coal burning

    Energy Technology Data Exchange (ETDEWEB)

    Li, X.; Pi, J.B.; Li, B.; Xu, Y.Y.; Jin, Y.P.; Sun, G.F. [China Medical University, Shenyang (China). Dept. for Occupational & Environmental Health

    2008-10-15

    In contrast to arsenicosis caused by consumption of water contaminated by naturally occurring inorganic arsenic, human exposure to this metalloid through coal burning has been rarely reported. In this study, arsenic speciation and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in urine were determined in the Chinese residents exposed to arsenic through coal burning in Guizhou, China, an epidemic area of chronic arsenic poisoning caused by coal burning. The urinary concentrations of inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and total arsenic (tAs) of high-arsenic exposed subjects were significantly higher than those of low-arsenic exposed residents. A biomarker of oxidative DNA damage, urinary 8-OHdG level was significantly higher in high-arsenic exposed subjects than that of low exposed. Significant positive correlations were found between 8-OHdG levels and concentrations of iAs, MMA, DMA and tAs, respectively. In addition, a significant negative correlation was observed between 8-OHdG levels and the secondary methylation ratio (DMA/(MMA + DMA)). The results suggest that chronic arsenic exposure through burning coal rich in arsenic is associated with oxidative DNA damages, and that secondary methylation capacity is potentially related to the susceptibility of individuals to oxidative DNA damage induced by arsenic exposure through coal burning in domestic living.

  6. Enhanced tomato disease resistance primed by arbuscular mycorrhizal fungus.

    Science.gov (United States)

    Song, Yuanyuan; Chen, Dongmei; Lu, Kai; Sun, Zhongxiang; Zeng, Rensen

    2015-01-01

    Roots of most terrestrial plants form symbiotic associations (mycorrhiza) with soil- borne arbuscular mycorrhizal fungi (AMF). Many studies show that mycorrhizal colonization enhances plant resistance against pathogenic fungi. However, the mechanism of mycorrhiza-induced disease resistance remains equivocal. In this study, we found that mycorrhizal inoculation with AMF Funneliformis mosseae significantly alleviated tomato (Solanum lycopersicum Mill.) early blight disease caused by Alternaria solani Sorauer. AMF pre-inoculation led to significant increases in activities of β-1,3-glucanase, chitinase, phenylalanine ammonia-lyase (PAL) and lipoxygenase (LOX) in tomato leaves upon pathogen inoculation. Mycorrhizal inoculation alone did not influence the transcripts of most genes tested. However, pathogen attack on AMF-inoculated plants provoked strong defense responses of three genes encoding pathogenesis-related proteins, PR1, PR2, and PR3, as well as defense-related genes LOX, AOC, and PAL, in tomato leaves. The induction of defense responses in AMF pre-inoculated plants was much higher and more rapid than that in un-inoculated plants in present of pathogen infection. Three tomato genotypes: a Castlemart wild-type (WT) plant, a jasmonate (JA) biosynthesis mutant (spr2), and a prosystemin-overexpressing 35S::PS plant were used to examine the role of the JA signaling pathway in AMF-primed disease defense. Pathogen infection on mycorrhizal 35S::PS plants led to higher induction of defense-related genes and enzymes relative to WT plants. However, pathogen infection did not induce these genes and enzymes in mycorrhizal spr2 mutant plants. Bioassays showed that 35S::PS plants were more resistant and spr2 plants were more susceptible to early blight compared with WT plants. Our finding indicates that mycorrhizal colonization enhances tomato resistance to early blight by priming systemic defense response, and the JA signaling pathway is essential for mycorrhiza

  7. Adverse health effects due to arsenic exposure: Modification by dietary supplementation of jaggery in mice

    International Nuclear Information System (INIS)

    Singh, Nrashant; Kumar, D.; Lal, Kewal; Raisuddin, S.; Sahu, Anand P.

    2010-01-01

    Populations of villages of eastern India and Bangladesh and many other parts of the world are exposed to arsenic mainly through drinking water. Due to non-availability of safe drinking water they are compelled to depend on arsenic-contaminated water. Generally, poverty level is high in those areas and situation is compounded by the lack of proper nutrition. The hypothesis that the deleterious health effects of arsenic can be prevented by modification of dietary factors with the availability of an affordable and indigenous functional food jaggery (sugarcane juice) has been tested in the present study. Jaggery contains polyphenols, vitamin C, carotene and other biologically active components. Arsenic as sodium-m-arsenite at low (0.05 ppm) and high (5 ppm) doses was orally administered to Swiss male albino mice, alone and in combination with jaggery feeding (250 mg/mice), consecutively for 180 days. The serum levels of total antioxidant, glutathione peroxidase and glutathione reductase were substantially reduced in arsenic-exposed groups, while supplementation of jaggery enhanced their levels in combined treatment groups. The serum levels of interleukin-1β, interleukin-6 and TNF-α were significantly increased in arsenic-exposed groups, while in the arsenic-exposed and jaggery supplemented groups their levels were normal. The comet assay in bone marrow cells showed the genotoxic effects of arsenic, whereas combination with jaggery feeding lessened the DNA damage. Histopathologically, the lung of arsenic-exposed mice showed the necrosis and degenerative changes in bronchiolar epithelium with emphysema and thickening of alveolar septa which was effectively antagonized by jaggery feeding. These results demonstrate that jaggery, a natural functional food, effectively antagonizes many of the adverse effects of arsenic.

  8. Method of arsenic removal from water

    Science.gov (United States)

    Gadgil, Ashok

    2010-10-26

    A method for low-cost arsenic removal from drinking water using chemically prepared bottom ash pre-treated with ferrous sulfate and then sodium hydroxide. Deposits on the surface of particles of bottom ash form of activated iron adsorbent with a high affinity for arsenic. In laboratory tests, a miniscule 5 grams of pre-treated bottom ash was sufficient to remove the arsenic from 2 liters of 2400 ppb (parts per billion) arsenic-laden water to a level below 50 ppb (the present United States Environmental Protection Agency limit). By increasing the amount of pre-treated bottom ash, even lower levels of post-treatment arsenic are expected. It is further expected that this invention supplies a very low-cost solution to arsenic poisoning for large population segments.

  9. Effects of genetic modifications to flax (Linum usitatissimum) on arbuscular mycorrhiza and plant performance.

    Science.gov (United States)

    Wróbel-Kwiatkowska, Magdalena; Turnau, Katarzyna; Góralska, Katarzyna; Anielska, Teresa; Szopa, Jan

    2012-10-01

    Although arbuscular mycorrhizal fungi (AMF) are known for their positive effect on flax growth, the impact of genetic manipulation in this crop on arbuscular mycorrhiza and plant performance was assessed for the first time. Five types of transgenic flax that were generated to improve fiber quality and resistance to pathogens, through increased levels of either phenylpropanoids (W92.40), glycosyltransferase (GT4, GT5), or PR2 beta-1,3-glucanase (B14) or produce polyhydroxybutyrate (M50), were used. Introduced genetic modifications did not change the degree of mycorrhizal colonization as compared to parent cultivars Linola and Nike. Arbuscules were well developed in each tested transgenic type (except M50). In two lines (W92.40 and B14), a higher abundance of arbuscules was observed when compared to control, untransformed flax plants. However, in some cases (W92.40, GT4, GT5, and B14 Md), the mycorrhizal dependency for biomass production of transgenic plants was slightly lower when compared to the original cultivars. No significant influence of mycorrhiza on the photosynthetic activity of transformed lines was found, but in most cases P concentration in mycorrhizal plants remained higher than in nonmycorrhizal ones. The transformed flax lines meet the demands for better quality of fiber and higher resistance to pathogens, without significantly influencing the interaction with AMF.

  10. Microbial Community Structure and Arsenic Biogeochemistry in Two Arsenic-Impacted Aquifers in Bangladesh

    Directory of Open Access Journals (Sweden)

    Edwin T. Gnanaprakasam

    2017-11-01

    Full Text Available Long-term exposure to trace levels of arsenic (As in shallow groundwater used for drinking and irrigation puts millions of people at risk of chronic disease. Although microbial processes are implicated in mobilizing arsenic from aquifer sediments into groundwater, the precise mechanism remains ambiguous. The goal of this work was to target, for the first time, a comprehensive suite of state-of-the-art molecular techniques in order to better constrain the relationship between indigenous microbial communities and the iron and arsenic mineral phases present in sediments at two well-characterized arsenic-impacted aquifers in Bangladesh. At both sites, arsenate [As(V] was the major species of As present in sediments at depths with low aqueous As concentrations, while most sediment As was arsenite [As(III] at depths with elevated aqueous As concentrations. This is consistent with a role for the microbial As(V reduction in mobilizing arsenic. 16S rRNA gene analysis indicates that the arsenic-rich sediments were colonized by diverse bacterial communities implicated in both dissimilatory Fe(III and As(V reduction, while the correlation analyses involved phylogenetic groups not normally associated with As mobilization. Findings suggest that direct As redox transformations are central to arsenic fate and transport and that there is a residual reactive pool of both As(V and Fe(III in deeper sediments that could be released by microbial respiration in response to hydrologic perturbation, such as increased groundwater pumping that introduces reactive organic carbon to depth.

  11. Distributional patterns of arsenic concentrations in contaminant plumes offer clues to the source of arsenic in groundwater at landfills

    Science.gov (United States)

    Harte, Philip T.

    2015-01-01

    The distributional pattern of dissolved arsenic concentrations from landfill plumes can provide clues to the source of arsenic contamination. Under simple idealized conditions, arsenic concentrations along flow paths in aquifers proximal to a landfill will decrease under anthropogenic sources but potentially increase under in situ sources. This paper presents several conceptual distributional patterns of arsenic in groundwater based on the arsenic source under idealized conditions. An example of advanced subsurface mapping of dissolved arsenic with geophysical surveys, chemical monitoring, and redox fingerprinting is presented for a landfill site in New Hampshire with a complex flow pattern. Tools to assist in the mapping of arsenic in groundwater ultimately provide information on the source of contamination. Once an understanding of the arsenic contamination is achieved, appropriate remedial strategies can then be formulated.

  12. Study of groundwater arsenic pollution in Lanyang Plain using multivariate statistical analysis

    Science.gov (United States)

    chan, S.

    2013-12-01

    The study area, Lanyang Plain in the eastern Taiwan, has highly developed agriculture and aquaculture, which consume over 70% of the water supplies. Groundwater is frequently considered as an alternative water source. However, the serious arsenic pollution of groundwater in Lanyan Plain should be well studied to ensure the safety of groundwater usage. In this study, 39 groundwater samples were collected. The results of hydrochemistry demonstrate two major trends in Piper diagram. The major trend with most of groundwater samples is determined with water type between Ca+Mg-HCO3 and Na+K-HCO3. This can be explained with cation exchange reaction. The minor trend is obviously corresponding to seawater intrusion, which has water type of Na+K-Cl, because the localities of these samples are all in the coastal area. The multivariate statistical analysis on hydrochemical data was conducted for further exploration on the mechanism of arsenic contamination. Two major factors can be extracted with factor analysis. The major factor includes Ca, Mg and Sr while the minor factor includes Na, K and As. This reconfirms that cation exchange reaction mainly control the groundwater hydrochemistry in the study area. It is worth to note that arsenic is positively related to Na and K. The result of cluster analysis shows that groundwater samples with high arsenic concentration can be grouped into that with high Na, K and HCO3. This supports that cation exchange would enhance the release of arsenic and exclude the effect of seawater intrusion. In other words, the water-rock reaction time is key to obtain higher arsenic content. In general, the major source of arsenic in sediments include exchangeable, reducible and oxidizable phases, which are adsorbed ions, Fe-Mn oxides and organic matters/pyrite, respectively. However, the results of factor analysis do not show apparent correlation between arsenic and Fe/Mn. This may exclude Fe-Mn oxides as a major source of arsenic. The other sources

  13. Effect of alpha-lipoic acid on the removal of arsenic from arsenic-loaded isolated liver tissues of rat

    Directory of Open Access Journals (Sweden)

    Noor-E-Tabassum

    2006-06-01

    Full Text Available The patient of chronic arsenic toxicity shows oxidative stress. To overcome the oxidative stress, several antioxidants such as beta-carotene, ascorbic acid, α-tocopherol, zinc and selenium had been suggested in the treatment of chronic arsenic toxicity. In the present study universal antioxidant (both water and lipid soluble antioxidant α-lipoic acid was used to examine the effectiveness of reducing the amount of arsenic from arsenic-loaded isolated liver tissues of rat. Isolated liver tissues of Long Evans Norwegian rats were cut into small pieces and incubated first in presence or absence of arsenic and then with different concentrations of α-lipoic acid during the second incubation. α-Lipoic acid decreases the amount of arsenic and malondialdehyde (MDA in liver tissues as well as increases the reduced glutathione (GSH level in dose dependent manner. These results suggest that α-lipoic acid remove arsenic from arsenic-loaded isolated liver tissues of rat.

  14. Poisoning of bees by industrial arsenic emissions

    Energy Technology Data Exchange (ETDEWEB)

    Jaroslav, S

    1962-01-01

    Massive poisoning of bees by industrial arsenic emissions in Czechoslovakia are reviewed. Arsenic emissions from an ore processing plant in Tesin were responsible for massive bee deaths after World War I. Massive death of bees was observed in 1938 in the Krompach region around a copper ore smelting plant which emitted arsenic. Other accidents were reported in 1954 and 1957 in areas around industrial plants and power plants using arsenopyrite-containing low-grade coal or lignite. Arsenic was emitted bound in fly-ash in the form of arsenic trioxide or, in the case of coals containing alkaline chlorides, in the form of arsenic trichloride. The arsenic contamination extended to areas within a radius of 3 to 7 km. Settled fly-ash contained 0.0004 to 0.75 percent arsenic, which was soluble in a citrate-hydrochloric acid solution of pH 3.9, which corresponds to the gastric acid of bees. The arsenic uptake by the bees from pollen was calculated to amount to 1 microgram daily, against a toxic dose of 0.37 microgram. The toxic effect of arsenic on bees can be abated by adding colloidal iron hydroxide to the sugar solution which they are fed.

  15. Poisoning of bees by industrial arsenic emissions

    Energy Technology Data Exchange (ETDEWEB)

    Svoboda, J

    1962-01-01

    Massive poisoning of bees by industrial arsenic emissions in Czechoslovakia are reviewed. Arsenic emissions from an ore processing plant in Tesin were responsible for massive bee deaths after World War I. Massive death of bees was observed in 1938 in the Krompach region around a copper ore smelting plant which emitted arsenic. Other accidents were reported in 1954 and 1957 in areas around industrial plants and power plants using arsenopyrite-containing low-grade coal or lignite. Arsenic was emitted bound in fly-ash in the form of arsenic trioxide or, in the case of coals containing alkaline chlorides, in the form of arsenic trichloride. The arsenic contamination extended to areas within a radius of 3-7 km. Settled fly-ash contained 0.0004-0.75% arsenic, which was soluble in a citrate-hydrochloric acid solution of pH 3.9, which corresponds to the gastric acid of bees. The arsenic uptake by the bees from pollen was calculated to amount to 1 microgram daily, against a toxic dose of 0.37 microgram. The toxic effect of arsenic on bees can be abated by adding colloidal iron hydroxide to the sugar solution which they are fed. 5 references.

  16. Immunotoxicological effects of inorganic arsenic on gilthead seabream (Sparus aurata L.)

    Energy Technology Data Exchange (ETDEWEB)

    Guardiola, F.A.; Gónzalez-Párraga, M.P.; Cuesta, A. [Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Meseguer, J. [Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Department of Agricultural Chemistry, Geology and Pedology, Faculty of Chemistry, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Martínez, S.; Martínez-Sánchez, M.J.; Pérez-Sirvent, C. [Department of Agricultural Chemistry, Geology and Pedology, Faculty of Chemistry, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain); Esteban, M.A., E-mail: aesteban@um.es [Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional “Campus Mare Nostrum”, University of Murcia, 30100 Murcia (Spain)

    2013-06-15

    Highlights: •Short exposure to arsenic increases the hepato-somatic index and produces histopathological alterations in the liver. •Arsenic is bioaccumulated in the liver of gilthead seabream but no in the muscle. •Arsenic-exposure affects the innate immune system in the gilthead seabream. •Ten days of exposure to As enhances the immune parameters. -- Abstract: Arsenic (As) has been associated with multitude of animal and human health problems; however, its impact on host immune system has not been extensively investigated. In fish, there are very few works on the potential risks or problems associated to the presence of arsenic. In the present study we have evaluated the effects of exposure (30 days) to sub-lethal concentrations of arsenic (5 μM As{sub 2}O{sub 3}) in the teleost fish gilthead seabream (Sparus aurata), with special emphasis in the innate immune response. The arsenic concentration was determined using atomic fluorescence spectrometry (AFS) in liver and muscle of exposed fish showing As accumulation in the liver after 30 days of exposure. The hepatosomatic index was increased at significant extent after 10 days but returned to control values after 30 days of exposure. Histological alterations in the liver were observed including hypertrophy, vacuolization and cell-death processes. Focusing on the immunological response, the humoral immune parameters (seric IgM, complement and peroxidase activities) were no affected to a statistically significant extent. Regarding the cellular innate parameters, head-kidney leucocyte peroxidase, respiratory burst and phagocytic activities were significantly increased after 10 days of exposition compared to the control fish. Overall, As-exposure in the seabream affects the immune system. How this might interfere with fish biology, aquaculture management or human consumers warrants further investigations. This paper describes, for the first time, the immunotoxicological effects of arsenic exposure in the

  17. Airborne arsenic and urinary excretion of arsenic metabolites during boiler cleaning operations in a Slovak coal-fired power plant

    Energy Technology Data Exchange (ETDEWEB)

    Yager, J.W.; Hicks, J.B.; Fabianova, N. [EPRI, Palo Alto, CA (United States). Environment Group

    1997-08-01

    Little information is available on the relationship between occupational exposure to inorganic arsenic in coal fly ash and urinary excretion of arsenic metabolites. This study was undertaken in a coal-fired power plant in Slovakia during a routine maintenance outage. Arsenic was measured in the breathing zone of workers during 5 consecutive workdays, and urine samples were obtained for analysis of arsenic metabolites-inorganic arsenic (As), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) prior to the start of each shift. Results from a small number of cascade impacter air samples indicated that approximately 90% of total particle mass and arsenic was present in particle size fractions {ge} 3.5 {mu}m. The 8-hr time-weighted average (TWA) mean arsenic air concentration was 48.3 {mu}g/m{sup 3} (range 0.17-375.2) and the mean sum of urinary arsenic (Sigma As) metabolites was 16.9 {mu}g As/g creatinine (range 2.6-50.8). For an 8-hr TWA of 10 {mu}g/m{sup 3} arsenic from coal fly ash, the predicted mean concentration f the Sigma As urinary metabolites was 13.2 {mu}g As/g creatinine. Comparisons with previously published studies of exposure to arsenic trioxide vapors and dusts in copper smelters suggest that bioavailability of arsenic from airborne coal fly ash (as indicated by urinary excretion) is about one-third that seen in smelters and similar settings. Arsenic compound characteristics, matrix composition, and particle size distribution probably play major roles in determining actual uptake of airborne arsenic.

  18. Contribution of arsenic species in unicellular algae to the cycling of arsenic in marine ecosystems.

    Science.gov (United States)

    Duncan, Elliott G; Maher, William A; Foster, Simon D

    2015-01-06

    This review investigates the arsenic species produced by and found in marine unicellular algae to determine if unicellular algae contribute to the formation of arsenobetaine (AB) in higher marine organisms. A wide variety of arsenic species have been found in marine unicellular algae including inorganic species (mainly arsenate--As(V)), methylated species (mainly dimethylarsenate (DMA)), arsenoribosides (glycerol, phosphate, and sulfate) and metabolites (dimethylarsenoethanol (DMAE)). Subtle differences in arsenic species distributions exist between chlorophyte and heterokontophyte species with As(V) commonly found in water-soluble cell fractions of chlorophyte species, while DMA is more common in heterokontophyte species. Additionally, different arsenoriboside species are found in each phyla with glycerol and phosphate arsenoribosides produced by chlorophytes, whereas glycerol, phosphate, and sulfate arsenoribosides are produced by heterokontophytes, which is similar to existing data for marine macro-algae. Although arsenoribosides are the major arsenic species in many marine unicellular algal species, AB has not been detected in unicellular algae which supports the hypothesis that AB is formed in marine animals via the ingestion and further metabolism of arsenoribosides. The observation of significant DMAE concentrations in some unicellular algal cultures suggests that unicellular algae-based detritus contains arsenic species that can be further metabolized to form AB in higher marine organisms. Future research establishing how environmental variability influences the production of arsenic species by marine unicellular algae and what effect this has on arsenic cycling within marine food webs is essential to clarify the role of these organisms in marine arsenic cycling.

  19. Evidence against the nuclear in situ binding of arsenicals-oxidative stress theory of arsenic carcinogenesis

    International Nuclear Information System (INIS)

    Kitchin, Kirk T.; Wallace, Kathleen

    2008-01-01

    A large amount of evidence suggests that arsenicals act via oxidative stress in causing cancer in humans and experimental animals. It is possible that arsenicals could bind in situ close to nuclear DNA followed by Haber-Weiss type oxidative DNA damage. Therefore, we tested this hypothesis by using radioactive 73 As labeled arsenite and vacuum filtration methodology to determine the binding affinity and capacity of 73 As arsenite to calf thymus DNA and Type 2A unfractionated histones, histone H3, H4 and horse spleen ferritin. Arsenicals are known to release redox active Fe from ferritin. At concentrations up to about 1 mM, neither DNA nor any of the three proteins studied, Type II-A histones, histone H3, H4 or ferritin, bound radioactive arsenite in a specific manner. Therefore, it appears highly unlikely that initial in situ binding of trivalent arsenicals, followed by in situ oxidative DNA damage, can account for arsenic's carcinogenicity. This experimental evidence (lack of arsenite binding to DNA, histone Type II-A and histone H3, H4) does not rule out other possible oxidative stress modes of action for arsenic such as (a) diffusion of longer lived oxidative stress molecules, such as H 2 O 2 into the nucleus and ensuing oxidative damage, (b) redox chemistry by unbound arsenicals in the nucleus, or (c) arsenical-induced perturbations in Fe, Cu or other metals which are already known to oxidize DNA in vitro and in vivo

  20. Application of Spent Mushroom Compost and Mycorrhiza on Yield and Yield Components of Garlic (Allium sativum L. in the Low Input Cropping System

    Directory of Open Access Journals (Sweden)

    P rezvani moghaddam

    2017-10-01

    Full Text Available Introduction In recent years, the effect of exogenous organic amendments on soil properties and plant growth characteristics has received renewed attention. Although the utilization of mineral fertilizers could be viewed as the best solution in terms of plant productivity, this approach is often inefficient in the long-term in tropical ecosystems due to the limited ability of low-activity clay soils to retain nutrients. Intensive use of agrochemicals in agricultural systems is also known to have irreversible effects on soil and water resources. The use of organic and biological fertilizers are important strategies to reduce harmful effects of chemical fertilizers in sustainable management of agroecosystems. Spent mushroom compost is the residual compost waste generated by the mushroom production industry. It is readily available and its formulation generally consists of a combination of wheat straw, dried blood, horse manure and ground chalk, composted together. It is an excellent source of humus, although much of its nitrogen content will have been used up by the composting and growing mushrooms. It remains, however, a good source of general nutrients, as well as a useful soil conditioner. Most mineral soils contain mycorrhizal fungi, but often at levels that are too low for adequate colonization, especially in disturbed soils. Mycorrhizae are host specific and will only colonize certain plants; so in some soils, there are no native mycorrhizae that will benefit these plants. Therefore, most plants would benefit from mycorrhizae addition to the soil. Symbiosis begins when fungal spores germinate and emerging thread linke structures, called hyphae, enters the epidermis of plant roots. After colonization of the root, the fungus sends out a vast network of hyphae throughout the soil to form a greatly enhanced absorptive surface area. This results in improved nutrient acquisition and uptake by plant roots, particularly elemental phosphorus, zinc

  1. Combination of siRNA-directed Kras oncogene silencing and arsenic-induced apoptosis using a nanomedicine strategy for the effective treatment of pancreatic cancer.

    Science.gov (United States)

    Zeng, Linjuan; Li, Jingguo; Wang, Yong; Qian, Chenchen; Chen, Yinting; Zhang, Qiubo; Wu, Wei; Lin, Zhong; Liang, Jianzhong; Shuai, Xintao; Huang, Kaihong

    2014-02-01

    The synergetic inhibitory effects on human pancreatic cancer by nanoparticle-mediated siRNA and arsenic therapy were investigated both in vitro and in vivo. Poly(ethylene glycol)-block-poly(L-lysine) were prepared to form siRNA-complexed polyplex and poly(ethylene glycol)-block-poly(DL-lactide) were prepared to form arsenic-encapsulated vesicle, respectively. Down-regulation of the mutant Kras gene by siRNA caused defective abilities of proliferation, clonal formation, migration, and invasion of pancreatic cancer cells, as well as cell cycle arrest at the G0/G1 phase, which substantially enhanced the apoptosis-inducing effect of arsenic administration. Consequently, co-administration of the two nanomedicines encapsulating siRNA or arsenic showed ideal tumor growth inhibition both in vitro and in vivo as a result of synergistic effect of the siRNA-directed Kras oncogene silencing and arsenic-induced cell apoptosis. These results suggest that the combination of mutant Kras gene silencing and arsenic therapy using nanoparticle-mediated delivery strategy is promising for pancreatic cancer treatment. Treatment of pancreatic cancer remains a major challenge. These authors demonstrate a method that combines a siRNA-based Kras silencing with arsenic delivery to pancreatic cancer cells using nanoparticles, resulting in enhanced apoptosis induction in the treated cells. © 2013.

  2. The Petunia GRAS Transcription Factor ATA/RAM1 Regulates Symbiotic Gene Expression and Fungal Morphogenesis in Arbuscular Mycorrhiza1

    Science.gov (United States)

    Rich, Mélanie K.

    2015-01-01

    Arbuscular mycorrhiza (AM) is a mutual symbiosis that involves a complex symbiotic interface over which nutrients are exchanged between the plant host and the AM fungus. Dozens of genes in the host are required for the establishment and functioning of the interaction, among them nutrient transporters that mediate the uptake of mineral nutrients delivered by the fungal arbuscules. We have isolated in a genetic mutant screen a petunia (Petunia hybrida) GIBBERELLIC ACID INSENSITIVE, REPRESSOR of GIBBERELLIC ACID INSENSITIVE, and SCARECROW (GRAS)-type transcription factor, ATYPICAL ARBUSCULE (ATA), that acts as the central regulator of AM-related genes and is required for the morphogenesis of arbuscules. Forced mycorrhizal inoculations from neighboring wild-type plants revealed an additional role of ATA in restricting mycorrhizal colonization of the root meristem. The lack of ATA, which represents the ortholog of REQUIRED FOR ARBUSCULAR MYCORRHIZA1 in Medicago truncatula, renders the interaction completely ineffective, hence demonstrating the central role of AM-related genes for arbuscule development and function. PMID:25971550

  3. An attempt to electrically enhance phytoremediation of arsenic contaminated water

    KAUST Repository

    Kubiak, Jan J.

    2012-04-01

    Water polluted with arsenic presents a challenge for remediation. A combination of phyto- and electro-remediation was attempted in this study. Four tanks were setup in order to assess the arsenic removal ability of the two methods separately and in combination. Lemna minor was chosen for As remediation and collected from a ditch in Utrecht, The Netherlands. The tanks were filled with surface water without any pre-cleaning, therefore containing various elements including metals as Mn (2.9mgL -1), Cu (0.05mgL -1), Fe (1.39mgL -1), and Ba (0.13mgL -1). This water was then spiked with As and allocated to a feed container, guaranteeing a continuous flow of 0.12mLs -1 to each tank. Two experiments were performed: Exp. 1 with 3 consecutive stages with rising applied voltage and Exp. 2, with a constant voltage over a period of 6d. Measurements of pH and temperature were taken every working day, as well as water samples from outlets of all tanks including feed container for control. From the present study, there was no evidence that As had been taken up by the plants, but a strong depletion of As was observed in the tanks where current was applied. Preliminary results clearly showed that applying voltage to the electrodes caused 90% removal of As from the spiked surface water. © 2012 .

  4. Chromosome analysis of arsenic affected cattle

    Directory of Open Access Journals (Sweden)

    S. Shekhar

    2014-10-01

    Full Text Available Aim: The aim was to study the chromosome analysis of arsenic affected cattle. Materials and Methods: 27 female cattle (21 arsenic affected and 6 normal were selected for cytogenetical study. The blood samples were collected, incubated, and cultured using appropriate media and specific methods. The samples were analyzed for chromosome number and morphology, relative length of the chromosome, arm ratio, and centromere index of X chromosome and chromosomal abnormalities in arsenic affected cattle to that of normal ones. Results: The diploid number of metaphase chromosomes in arsenic affected cattle as well as in normal cattle were all 2n=60, 58 being autosomes and 2 being sex chromosomes. From the centromeric position, karyotyping studies revealed that all the 29 pair of autosomes was found to be acrocentric or telocentric, and the sex chromosomes (XX were submetacentric in both normal and arsenic affected cattle. The relative length of all the autosome pairs and sex chrosomosome pair was found to be higher in normal than that of arsenic affected cattle. The mean arm ratio of X-chromosome was higher in normal than that of arsenic affected cattle, but it is reverse in case of centromere index value of X-chromosome. There was no significant difference of arm ratio and centromere index of X-chromosomes between arsenic affected and normal cattle. No chromosomal abnormalities were found in arsenic affected cattle. Conclusion: The chromosome analysis of arsenic affected cattle in West Bengal reported for the first time in this present study which may serve as a guideline for future studies in other species. These reference values will also help in comparison of cytological studies of arsenic affected cattle to that of various toxicants.

  5. Effects of arbuscular mycorrhizal inoculation on plants growing on arsenic contaminated soil.

    Science.gov (United States)

    Jankong, P; Visoottiviseth, P

    2008-07-01

    Arbuscular mycorrhizal fungi (AMF) may play an important role in phytoremediation of As-contaminated soil. In this study the effects of AMF (Glomus mosseae, Glomus intraradices and Glomus etunicatum) on biomass production and arsenic accumulation in Pityrogramma calomelanos, Tagetes erecta and Melastoma malabathricum were investigated. Soil (243 +/- 13 microg As g(-1)) collected from Ron Phibun District, an As-contaminated area in Thailand, was used in a greenhouse experiment. The results showed different effects of AMF on phytoremediation of As-contaminated soil by different plant species. For P. calomelanos and T. erecta, AMF reduced only arsenic accumulation in plants but had no significant effect on plant growth. In contrast, AMF improved growth and arsenic accumulation in M. malabathricum. These findings show the importance of understanding different interactions between AMF and their host plants for enhancing phytoremediation of As-contaminated soils.

  6. Geomicrobial interactions with arsenic and antimony

    Science.gov (United States)

    Oremland, Ronald S.

    2015-01-01

    Although arsenic and antimony are generally toxic to life, some microorganisms exist that can metabolize certain forms of these elements. Some can use arsenite or stibnite as potential or sole energy sources, whereas others can use aresenate and antimonite (as was discovered only recently) as terminal electron acceptors. Still other microbes can metabolize arsenic and antimony compounds to detoxify them. These reactions are important from a geomicrobial standpoint because they indicate that a number of microbes contribute to arsenic and antimony mobilization or immobilization in the environment and play a role in arsenic and antimony cycles. Recent reviews include five on prokaryotes and arsenic metabolism, a review with an arsenic perspective on biomining, and a series on environmental antimony, including one about antimony and its interaction with microbiota.

  7. Arsenic uptake and phytoremediation potential by arbuscular mycorrhizal fungi

    Science.gov (United States)

    Xinhua He; Erik Lilleskov

    2014-01-01

    Arsenic (As) contamination of soils and water is a global problem because of its impacts on ecosystems and human health. Various approaches have been attempted for As remediation, with limited success. Arbuscular mycorrhizal (AM) fungi play vital roles in the uptake of water and essential nutrients, especially phosphorus (P), and hence enhance plant performance and...

  8. Arsenic exposure, urinary arsenic speciation, and peripheral vascular disease in blackfoot disease-hyperendemic villages in Taiwan

    International Nuclear Information System (INIS)

    Tseng, C.-H.; Huang, Y.-K.; Huang, Y.-L.; Chung, C.-J.; Yang, M.-H.; Chen, C.-J.; Hsueh, Y.-M.

    2005-01-01

    Long-term exposure to ingested inorganic arsenic is associated with peripheral vascular disease (PVD) in the blackfoot disease (BFD)-hyperendemic area in Taiwan. This study further examined the interaction between arsenic exposure and urinary arsenic speciation on the risk of PVD. A total of 479 (220 men and 259 women) adults residing in the BFD-hyperendemic area were studied. Doppler ultrasound was used to diagnose PVD. Arsenic exposure was estimated by an index of cumulative arsenic exposure (CAE). Urinary levels of total arsenic, inorganic arsenite (As III ) and arsenate (As V ), monomethylarsonic acid (MMA V ), and dimethylarsinic acid (DMA V ) were determined. Primary methylation index [PMI = MMA V /(As III + As V )] and secondary methylation index (SMI = DMA V /MMA V ) were calculated. The association between PVD and urinary arsenic parameters was evaluated with consideration of the interaction with CAE and the confounding effects of age, sex, body mass index, total cholesterol, triglycerides, cigarette smoking, and alcohol consumption. Results showed that aging was associated with a diminishing capacity to methylate inorganic arsenic and women possessed a more efficient arsenic methylation capacity than men did. PVD risk increased with a higher CAE and a lower capacity to methylate arsenic to DMA V . The multivariate-adjusted odds ratios for CAE of 0, 0.1-15.4, and >15.4 mg/L x year were 1.00, 3.41 (0.74-15.78), and 4.62 (0.96-22.21), respectively (P 6.93, PMI > 1.77 and SMI > 6.93, PMI > 1.77 and SMI ≤ 6.93, and PMI ≤ 1.77 and SMI ≤ 6.93 were 1.00, 2.93 (0.90-9.52), 2.85 (1.05-7.73), and 3.60 (1.12-11.56), respectively (P V have a higher risk of developing PVD in the BFD-hyperendemic area in Taiwan

  9. A new metabolic pathway of arsenite: arsenic-glutathione complexes are substrates for human arsenic methyltransferase Cyt19

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, Toru [National Institute for Environmental Studies, Environmental Health Sciences Division, Ibaraki (Japan); Chiba University, Faculty of Pharmaceutical Sciences, Chiba (Japan); Kobayashi, Yayoi; Cui, Xing; Hirano, Seishiro [National Institute for Environmental Studies, Environmental Health Sciences Division, Ibaraki (Japan)

    2005-04-01

    The metabolism of arsenic is generally accepted to proceed by repetitive reduction and oxidative methylation; the latter is mediated by arsenic methyltransferase (Cyt19). In human urine, the major metabolites of inorganic arsenicals such as arsenite (iAs{sup III}) and arsenate (iAs{sup V}) are monomethylarsonic acid (MMA{sup V}) and dimethylarsinic acid (DMA{sup V}). On the other hand, in rat bile, the major metabolites of iAs{sup III} have been reported to be arsenic-glutathione (As-GSH) complexes. In the present study we investigate whether these As-GSH complexes are substrates for arsenic methyltransferase by using human recombinant Cyt19. Analyses by high-performance liquid chromatography-inductively coupled plasma mass spectrometry suggested that arsenic triglutathione (ATG) was generated nonenzymatically from iAs{sup III} when GSH was present at concentrations 2 mM or higher. Human recombinant Cyt19 catalyzed transfer of a methyl group from S-adenosyl-l-methionine to arsenic and produced monomethyl and dimethyl arsenicals. The methylation of arsenic was catalyzed by Cyt19 only when ATG was present in the reaction mixture. Moreover, monomethylarsonic diglutathione (MADG) was a substrate of Cyt19 for further methylation to dimethylarsinic glutathione (DMAG). On the other hand, monomethylarsonous acid (MMA{sup III}), a hydrolysis product of MADG, was not methylated to dimethyl arsenical by Cyt19. These results suggest that As-GSH complexes such as ATG and MADG were converted by Cyt19 to MADG and DMAG, respectively. Both MADG and DMAG were unstable in solution when the GSH concentration was lower than 1 mM, and were hydrolyzed and oxidized to MMA{sup V} and DMA{sup V}, respectively. Metabolism of iAs{sup III} to methylated arsenicals by Cyt19 was via ATG and MADG rather than by oxidative methylation of iAs{sup III} and MMA{sup III}. (orig.)

  10. Novel root-fungus symbiosis in Ericaceae: sheathed ericoid mycorrhiza formed by a hitherto undescribed basidiomycete with affinities to Trechisporales

    Czech Academy of Sciences Publication Activity Database

    Vohník, Martin; Sadowsky, J. J.; Kohout, Petr; Lhotáková, Z.; Nestby, R.; Kolařík, Miroslav

    2012-01-01

    Roč. 7, č. 6 (2012), e39524 E-ISSN 1932-6203 R&D Projects: GA ČR GP206/09/P340 Institutional support: RVO:67985939 ; RVO:61388971 Keywords : ericoid mycorrhiza * Ericaceae * Basidiomycetes Subject RIV: EF - Botanics; EE - Microbiology, Virology (MBU-M) Impact factor: 3.730, year: 2012

  11. Arsenic in Drinking Water—A Global Environmental Problem

    Science.gov (United States)

    Shaofen Wang, Joanna; Wai, Chien M.

    2004-02-01

    Arsenic contamination of groundwater is a global environmental problem affecting a large number of populations, especially in developing countries. The "blackfoot disease"that occurred in Taiwan more than half of a century ago was attributed to drinking arsenic-contaminated water from deep wells containing high concentrations of the trivalent arsenite species. Similar arsenic poisoning cases were reported later in Chinese Inner Mongolia, Bangladesh, and India—all related to drinking groundwater contaminated with arsenic. The maximum contaminant level (MCL) of arsenic in drinking water has been changed recently by the U.S. EPA from 50 ppb to 10 ppb; the compliance date is January 2006. This article summarizes documented global arsenic contamination problems, the regulatory controversy regarding MCL of arsenic in drinking water, and available technologies for removing arsenic from contaminated waters. Methods for analyzing total arsenic and arsenic species in water are also described.

  12. [Study of relationship between arsenic methylation and skin lesion in a population with long-term high arsenic exposure].

    Science.gov (United States)

    Su, Liqin; Cheng, Yibin; Lin, Shaobin; Wu, Chuanye

    2007-05-01

    To investigate the difference of arsenic metabolism in populations with long-term high arsenic exposure and explore the relationship between arsenic metabolism diversity and skin lesion. 327 residents in an arsenic polluted village were voluntarily enrolled in this study. Questionnaire survey and medical examination were carried out to learn basic information and detect skin lesions. Urinary inorganic and methylated arsenic were speciated by high performance liquid chromatography combined with hydride-generation atomic fluorescence spectrometry. Total arsenic concentration in hair was determined with DDC-Ag method. Hair arsenic content of studied polutions was generally high, but no significant difference were found among the studied four groups. MMA and DMA concentration in urine increased with studied polution age, and were positively related with skin lesion grade. The relative proportion of MMA in serious skin lesion group was significantly higher than in other 3 groups, while DMA/MMA ratio was significantly lower than control and mild group. The relative proportion of MMA was positively related with skin lesion grade, DMA/ MMA ratio was negatively related with skin lesion grade. Males could have higher arsenic cumulation and lower methylation capacity than those of females. The population of above 40 years old may have higher methylation capacity than those of adults below 40yeas old. Smokers and drinkers seemed lower methylation capacity than those of non-smokers and non-drinkers respectively. The methylation of arsenic could affect by several factors, including age gender, smoking and drinking. Arsenic methylation copacity mey be associated with skin lesion induced by arsenic exposure.

  13. Arsenic speciation analysis of urine samples from individuals living in an arsenic-contaminated area in Bangladesh.

    Science.gov (United States)

    Hata, Akihisa; Yamanaka, Kenzo; Habib, Mohamed Ahsan; Endo, Yoko; Fujitani, Noboru; Endo, Ginji

    2012-05-01

    Chronic inorganic arsenic (iAs) exposure currently affects tens of millions of people worldwide. To accurately determine the proportion of urinary arsenic metabolites in residents continuously exposed to iAs, we performed arsenic speciation analysis of the urine of these individuals and determined whether a correlation exists between the concentration of iAs in drinking water and the urinary arsenic species content. The subjects were 165 married couples who had lived in the Pabna District in Bangladesh for more than 5 years. Arsenic species were measured using high-performance liquid chromatography and inductively coupled plasma mass spectrometry. The median iAs concentration in drinking water was 55 μgAs/L (range 47.9-153.4 μgAs/L), respectively. No arsenobetaine or arsenocholine was detected. The concentrations of the 4 urinary arsenic species were significantly and linearly related to each other. The urinary concentrations of total arsenic and each species were significantly correlated with the iAs concentration of drinking water. All urinary arsenic species are well correlated with each other and with iAs in drinking water. The most significant linear relationship existed between the iAs concentration in drinking water and urinary iAs + MMA concentration. From these results, combined with the effects of seafood ingestion, the best biomarker of iAs exposure is urinary iAs + MMA concentration.

  14. Arbuscular mycorrhizas are present on Spitsbergen.

    Science.gov (United States)

    Newsham, K K; Eidesen, P B; Davey, M L; Axelsen, J; Courtecuisse, E; Flintrop, C; Johansson, A G; Kiepert, M; Larsen, S E; Lorberau, K E; Maurset, M; McQuilkin, J; Misiak, M; Pop, A; Thompson, S; Read, D J

    2017-10-01

    A previous study of 76 plant species on Spitsbergen in the High Arctic concluded that structures resembling arbuscular mycorrhizas were absent from roots. Here, we report a survey examining the roots of 13 grass and forb species collected from 12 sites on the island for arbuscular mycorrhizal (AM) colonisation. Of the 102 individuals collected, we recorded AM endophytes in the roots of 41 plants of 11 species (Alopecurus ovatus, Deschampsia alpina, Festuca rubra ssp. richardsonii, putative viviparous hybrids of Poa arctica and Poa pratensis, Poa arctica ssp. arctica, Trisetum spicatum, Coptidium spitsbergense, Ranunculus nivalis, Ranunculus pygmaeus, Ranunculus sulphureus and Taraxacum arcticum) sampled from 10 sites. Both coarse AM endophyte, with hyphae of 5-10 μm width, vesicles and occasional arbuscules, and fine endophyte, consisting of hyphae of 1-3 μm width and sparse arbuscules, were recorded in roots. Coarse AM hyphae, vesicles, arbuscules and fine endophyte hyphae occupied 1.0-30.7, 0.8-18.3, 0.7-11.9 and 0.7-12.8% of the root lengths of colonised plants, respectively. Principal component analysis indicated no associations between the abundances of AM structures in roots and edaphic factors. We conclude that the AM symbiosis is present in grass and forb roots on Spitsbergen.

  15. Exiguobacterium mediated arsenic removal and its protective effect against arsenic induced toxicity and oxidative damage in freshwater fish, Channa striata

    Directory of Open Access Journals (Sweden)

    Neha Pandey

    2015-01-01

    Full Text Available Arsenic is a toxic metalloid existing widely in the environment, and its removal from contaminated water has become a global challenge. The use of bacteria in this regard finds a promising solution. In the present study, Exiguobacterium sp. As-9, which is an arsenic resistant bacterium, was selected with respect to its arsenic removal efficiency. Quantification of arsenic in the water treated with bacterium showed that Exiguobacterium efficiently removed up to 99% of arsenic in less than 20 h. In order to reveal the possible effect of this bacterium in removal of arsenic from water and protecting fishes from the detrimental effects of arsenic, we initiated a range of studies on fresh water fish, Channa striata. It was observed that the fishes introduced into bacteria treated water displayed no symptoms of arsenic toxicity which was marked by a decreased oxidative damage, whereas the fishes exposed to arsenic revealed a significant (p < 0.05 increase in the oxidative stress together with the elevated levels of malondialdehyde. Determination of the bioaccumulation of arsenic in the liver tissues of C. striata using hydride generation atomic absorption spectrophotometry (HG-AAS revealed an increased As(III accumulation in the fishes exposed to arsenic whereas the arsenic level in the control and bacteria treated fishes were found below the detectable limit. In conclusion, this study presents the strategies of bacterial arsenic removal with possible directions for future research.

  16. Microbial transformations of arsenic: perspectives for biological removal of arsenic from water

    NARCIS (Netherlands)

    Cavalca, L.; Corsini, A.; Zaccheo, P.; Andreoni, V.; Muyzer, G.

    2013-01-01

    Arsenic is present in many environments and is released by various natural processes and anthropogenic actions. Although arsenic is recognized to cause a wide range of adverse health effects in humans, diverse bacteria can metabolize it by detoxification and energy conservation reactions. This

  17. The Petunia GRAS Transcription Factor ATA/RAM1 Regulates Symbiotic Gene Expression and Fungal Morphogenesis in Arbuscular Mycorrhiza.

    Science.gov (United States)

    Rich, Mélanie K; Schorderet, Martine; Bapaume, Laure; Falquet, Laurent; Morel, Patrice; Vandenbussche, Michiel; Reinhardt, Didier

    2015-07-01

    Arbuscular mycorrhiza (AM) is a mutual symbiosis that involves a complex symbiotic interface over which nutrients are exchanged between the plant host and the AM fungus. Dozens of genes in the host are required for the establishment and functioning of the interaction, among them nutrient transporters that mediate the uptake of mineral nutrients delivered by the fungal arbuscules. We have isolated in a genetic mutant screen a petunia (Petunia hybrida) Gibberellic Acid Insensitive, Repressor of Gibberellic Acid Insensitive, and Scarecrow (GRAS)-type transcription factor, Atypical Arbuscule (ATA), that acts as the central regulator of AM-related genes and is required for the morphogenesis of arbuscules. Forced mycorrhizal inoculations from neighboring wild-type plants revealed an additional role of ATA in restricting mycorrhizal colonization of the root meristem. The lack of ATA, which represents the ortholog of Required For Arbuscular Mycorrhiza1 in Medicago truncatula, renders the interaction completely ineffective, hence demonstrating the central role of AM-related genes for arbuscule development and function. © 2015 American Society of Plant Biologists. All Rights Reserved.

  18. Adverse health effects due to arsenic exposure: modification by dietary supplementation of jaggery in mice.

    Science.gov (United States)

    Singh, Nrashant; Kumar, D; Lal, Kewal; Raisuddin, S; Sahu, Anand P

    2010-02-01

    Populations of villages of eastern India and Bangladesh and many other parts of the world are exposed to arsenic mainly through drinking water. Due to non-availability of safe drinking water they are compelled to depend on arsenic-contaminated water. Generally, poverty level is high in those areas and situation is compounded by the lack of proper nutrition. The hypothesis that the deleterious health effects of arsenic can be prevented by modification of dietary factors with the availability of an affordable and indigenous functional food jaggery (sugarcane juice) has been tested in the present study. Jaggery contains polyphenols, vitamin C, carotene and other biologically active components. Arsenic as sodium-m-arsenite at low (0.05 ppm) and high (5 ppm) doses was orally administered to Swiss male albino mice, alone and in combination with jaggery feeding (250 mg/mice), consecutively for 180 days. The serum levels of total antioxidant, glutathione peroxidase and glutathione reductase were substantially reduced in arsenic-exposed groups, while supplementation of jaggery enhanced their levels in combined treatment groups. The serum levels of interleukin-1beta, interleukin-6 and TNF-alpha were significantly increased in arsenic-exposed groups, while in the arsenic-exposed and jaggery supplemented groups their levels were normal. The comet assay in bone marrow cells showed the genotoxic effects of arsenic, whereas combination with jaggery feeding lessened the DNA damage. Histopathologically, the lung of arsenic-exposed mice showed the necrosis and degenerative changes in bronchiolar epithelium with emphysema and thickening of alveolar septa which was effectively antagonized by jaggery feeding. These results demonstrate that jaggery, a natural functional food, effectively antagonizes many of the adverse effects of arsenic. Copyright 2009 Elsevier Inc. All rights reserved.

  19. Linking Arsenic Metabolism and Toxic Effects

    Science.gov (United States)

    Although arsenic has been long recognized as a toxicant and a carcinogen, the molecular basis for few of its adverse effects are well understood. Like other metalloids, arsenic undergoes extensive metabolism involving oxidation state changes and formation of methyl-arsenic bonds ...

  20. Arsenic, Anaerobes, and Astrobiology

    Science.gov (United States)

    Stolz, J. F.; Oremland, R. S.; Switzer Blum, J.; Hoeft, S. E.; Baesman, S. M.; Bennett, S.; Miller, L. G.; Kulp, T. R.; Saltikov, C.

    2013-12-01

    Arsenic is an element best known for its highly poisonous nature, so it is not something one would associate with being a well-spring for life. Yet discoveries made over the past two decades have delineated that not only are some microbes resistant to arsenic, but that this element's primary redox states can be exploited to conserve energy and support prokaryotic growth ('arsenotrophy') in the absence of oxygen. Hence, arsenite [As(III)] can serve as an electron donor for chemo- or photo-autotrophy while arsenate [As(V)] will serve as an electron acceptor for chemo-heterotrophs and chemo-autotrophs. The phylogenetic diversity of these microbes is broad, encompassing many individual species from diverse taxonomic groups in the Domain Bacteria, with fewer representatives in the Domain Archaea. Speculation with regard to the evolutionary origins of the key functional genes in anaerobic arsenic transformations (arrA and arxA) and aerobic oxidation (aioB) has led to a disputation as to which gene and function is the most ancient and whether arsenic metabolism extended back into the Archaean. Regardless of its origin, robust arsenic metabolism has been documented in extreme environments that are rich in their arsenic content, such as hot springs and especially hypersaline soda lakes associated with volcanic regions. Searles Lake, CA is an extreme, salt-saturated end member where vigorous arsenic metabolism occurs, but there is no detectable sulfate-reduction or methanogenesis. The latter processes are too weak bio-energetically to survive as compared with arsenotrophy, and are also highly sensitive to the abundance of borate ions present in these locales. These observations have implications with respect to the search for microbial life elsewhere in the Solar System where volcanic-like processes have been operative. Hence, because of the likelihood of encountering dense brines in the regolith of Mars (formed by evapo-concentration) or beneath the ice layers of Europa

  1. Production of selenium-72 and arsenic-72

    Science.gov (United States)

    Phillips, D.R.

    1994-12-06

    Methods and apparatus are described for producing selenium-72, separating it from its daughter isotope arsenic-72, and generating multiple portions of a solution containing arsenic-72 from a reusable parent substance comprised of selenium-72. The invention provides apparatus which can be located at a site where arsenic-72 is used, for purposes such as PET imaging, to produce arsenic-72 as needed, since the half-life of arsenic-72 is very short. 2 figures.

  2. Arsenic removal by solar-driven membrane distillation: modeling and experimental investigation with a new flash vaporization module.

    Science.gov (United States)

    Pa, Parimal; Manna, Ajay Kumar; Linnanen, Lassi

    2013-01-01

    A modeling and simulation study was carried out on a new flux-enhancing and solar-driven membrane distillation module for removal of arsenic from contaminated groundwater. The developed new model was validated with rigorous experimental investigations using arsenic-contaminated groundwater. By incorporating flash vaporization dynamics, the model turned out to be substantially different from the existing direct contact membrane distillation models and could successfully predict (with relative error of only 0.042 and a Willmott d-index of 0.997) the performance of such an arsenic removal unit where the existing models exhibited wide variation with experimental findings in the new design. The module with greater than 99% arsenic removal efficiency and greater than 50 L/m2 x h flux could be implemented in arsenic-affected villages in Southeast Asian countries with abundant solar energy, and thus could give relief to millions of affected people. These encouraging results will raise scale-up confidence.

  3. Isolation of arsenic-tolerant bacteria from arsenic-contaminated soil

    Directory of Open Access Journals (Sweden)

    Vorasan Sobhon*

    2008-04-01

    Full Text Available The disposal of toxic heavy metals such as arsenic posed high risk to the environment. Arsenite [As(III], a reduced form of arsenic, is more toxic and mobile than arsenate [As(V]. The aim of this work was to isolate arsenic-tolerant bacteria from contaminated soil collected in Ronphibun District, Nakorn Srithammarat Province, followed by screening these bacteria for their ability to adsorb arsenite. Twenty-four bacterial isolates were obtained from samples cultivated in basal salts medium plus 0.1% yeast extract and up to 40 mM sodium-arsenite at 30oC under aerobic condition. From these, isolates B-2, B-3, B-4, B-21, B-25 and B-27 produced extracellular polymeric-like substances into the culture medium, which may potentially be used in the bioremediation of arsenic and other contaminants. All isolates displayed arsenite adsorbing activities in the ranges of 36.87-96.93% adsorption from initial concentration of 40 mM sodium-arsenite, without any arsenic transforming activity. Five isolates with the highest arsenite adsorbing capacity include B-4, B-7, B-8, B-10 and B-13 which adsorbed 80.90, 86.72, 87.08, 84.36 and 96.93% arsenite, respectively. Identification of their 16S rDNA sequences showed B -7, B-8, and B-10 to have 97%, 99% and 97% identities to Microbacterium oxydans, Achromobacter sp. and Ochrobactrum anthropi, respectively. Isolates B-4 and B-13, which did not show sequence similarity to any bacterial species, may be assigned based on their morphological and biochemical characteristics to the genus Streptococcus and Xanthomonas, respectively. Thus, both isolates B-4 and B-13 appear to be novel arsenite adsorbing bacteria within these genuses.

  4. Electrochemical arsenic remediation for rural Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Addy, Susan Amrose [Univ. of California, Berkeley, CA (United States)

    2008-01-01

    Arsenic in drinking water is a major public health problem threatening the lives of over 140 million people worldwide. In Bangladesh alone, up to 57 million people drink arsenic-laden water from shallow wells. ElectroChemical Arsenic Remediation(ECAR) overcomes many of the obstacles that plague current technologies and can be used affordably and on a small-scale, allowing for rapid dissemination into Bangladesh to address this arsenic crisis. In this work, ECAR was shown to effectively reduce 550 - 580 μg=L arsenic (including both As[III]and As[V]in a 1:1 ratio) to below the WHO recommended maximum limit of 10 μg=L in synthetic Bangladesh groundwater containing relevant concentrations of competitive ions such as phosphate, silicate, and bicarbonate. Arsenic removal capacity was found to be approximately constant within certain ranges of current density, but was found to change substantially between ranges. In order of decreasing arsenic removal capacity, the pattern was: 0.02 mA=cm2> 0.07 mA=cm2> 0.30 - 1.1 mA=cm2> 5.0 - 100 mA=cm2. Current processing time was found to effect arsenic removal capacity independent of either charge density or current density. Electrode polarization studies showed no passivation of the electrode in the tested range (up to current density 10 mA=cm2) and ruled out oxygen evolution as the cause of decreasing removal capacity with current density. Simple settling and decantation required approximately 3 days to achieve arsenic removal comparable to filtration with a 0.1 mu m membrane. X-ray Absorption Spectroscopy (XAS) showed that (1) there is no significant difference in the arsenic removal mechanism of ECAR during operation at different current densities and (2) the arsenic removal mechanism in ECAR is consistent with arsenate adsorption onto a homogenous Fe(III)oxyhydroxide similar in structure to 2-line ferrihydrite. ECAR effectively reduced high arsenic concentrations (100

  5. ARSENIC RESEARCH AT GWERD

    Science.gov (United States)

    Abstract - The presentation will summarize the arsenic research program at the Ground Water & Ecosystems Restoration Division of the National Risk Management Research Laboratory of USEPA. Topics include use of permeable reactive barriers for in situ arsenic remediation in ground...

  6. Arsenic-induced cutaneous hyperplastic lesions are associated with the dysregulation of Yap, a Hippo signaling-related protein

    International Nuclear Information System (INIS)

    Li, Changzhao; Srivastava, Ritesh K.; Elmets, Craig A.; Afaq, Farrukh; Athar, Mohammad

    2013-01-01

    Highlights: •Arsenic activates canonical Hippo signaling pathway and up-regulates αCatenin in the skin. •Arsenic activates transcriptional activity of Yap by its nuclear translocation. •Yap is involved in the disruption of tight/adherens junctions in arsenic-exposed animals. -- Abstract: Arsenic exposure in humans causes a number of toxic manifestations in the skin including cutaneous neoplasm. However, the mechanism of these alterations remains elusive. Here, we provide novel observations that arsenic induced Hippo signaling pathway in the murine skin. This pathway plays crucial roles in determining organ size during the embryonic development and if aberrantly activated in adults, contributes to the pathogenesis of epithelial neoplasm. Arsenic treatment enhanced phosphorylation-dependent activation of LATS1 kinase and other Hippo signaling regulatory proteins Sav1 and MOB1. Phospho-LATS kinase is known to catalyze the inactivation of a transcriptional co-activator, Yap. However, in arsenic-treated epidermis, we did not observed its inactivation. Thus, as expected, unphosphorylated-Yap was translocated to the nucleus in arsenic-treated epidermis. Yap by binding to the transcription factors TEADs induces transcription of its target genes. Consistently, an up-regulation of Yap-dependent target genes Cyr61, Gli2, Ankrd1 and Ctgf was observed in the skin of arsenic-treated mice. Phosphorylated Yap is important in regulating tight and adherens junctions through its binding to αCatenin. We found disruption of these junctions in the arsenic-treated mouse skin despite an increase in αCatenin. These data provide evidence that arsenic-induced canonical Hippo signaling pathway and Yap-mediated disruption of tight and adherens junctions are independently regulated. These effects together may contribute to the carcinogenic effects of arsenic in the skin

  7. Roxarsone, inorganic arsenic, and other arsenic species in chicken: a U.S.-based market basket sample.

    Science.gov (United States)

    Nachman, Keeve E; Baron, Patrick A; Raber, Georg; Francesconi, Kevin A; Navas-Acien, Ana; Love, David C

    2013-07-01

    Inorganic arsenic (iAs) causes cancer and possibly other adverse health outcomes. Arsenic-based drugs are permitted in poultry production; however, the contribution of chicken consumption to iAs intake is unknown. We sought to characterize the arsenic species profile in chicken meat and estimate bladder and lung cancer risk associated with consuming chicken produced with arsenic-based drugs. Conventional, antibiotic-free, and organic chicken samples were collected from grocery stores in 10 U.S. metropolitan areas from December 2010 through June 2011. We tested 116 raw and 142 cooked chicken samples for total arsenic, and we determined arsenic species in 65 raw and 78 cooked samples that contained total arsenic at ≥ 10 µg/kg dry weight. The geometric mean (GM) of total arsenic in cooked chicken meat samples was 3.0 µg/kg (95% CI: 2.5, 3.6). Among the 78 cooked samples that were speciated, iAs concentrations were higher in conventional samples (GM = 1.8 µg/kg; 95% CI: 1.4, 2.3) than in antibiotic-free (GM = 0.7 µg/kg; 95% CI: 0.5, 1.0) or organic (GM = 0.6 µg/kg; 95% CI: 0.5, 0.8) samples. Roxarsone was detected in 20 of 40 conventional samples, 1 of 13 antibiotic-free samples, and none of the 25 organic samples. iAs concentrations in roxarsone-positive samples (GM = 2.3 µg/kg; 95% CI: 1.7, 3.1) were significantly higher than those in roxarsone-negative samples (GM = 0.8 µg/kg; 95% CI: 0.7, 1.0). Cooking increased iAs and decreased roxarsone concentrations. We estimated that consumers of conventional chicken would ingest an additional 0.11 µg/day iAs (in an 82-g serving) compared with consumers of organic chicken. Assuming lifetime exposure and a proposed cancer slope factor of 25.7 per milligram per kilogram of body weight per day, this increase in arsenic exposure could result in 3.7 additional lifetime bladder and lung cancer cases per 100,000 exposed persons. Conventional chicken meat had higher iAs concentrations than did conventional antibiotic

  8. Arsenic mobilization and immobilization in paddy soils

    Science.gov (United States)

    Kappler, A.; Hohmann, C.; Zhu, Y. G.; Morin, G.

    2010-05-01

    Arsenic is oftentimes of geogenic origin and in many cases bound to iron(III) minerals. Iron(III)-reducing bacteria can harvest energy by coupling the oxidation of organic or inorganic electron donors to the reduction of Fe(III). This process leads either to dissolution of Fe(III)-containing minerals and thus to a release of the arsenic into the environment or to secondary Fe-mineral formation and immobilisation of arsenic. Additionally, aerobic and anaerobic iron(II)-oxidizing bacteria have the potential to co-precipitate or sorb arsenic during iron(II) oxidation at neutral pH that is usually followed by iron(III) mineral precipitation. We are currently investigating arsenic immobilization by Fe(III)-reducing bacteria and arsenic co-precipitation and immobilization by anaerobic iron(II)-oxidizing bacteria in batch, microcosm and rice pot experiments. Co-precipitation batch experiments with pure cultures of nitrate-dependent Fe(II)-oxidizing bacteria are used to quantify the amount of arsenic that can be immobilized during microbial iron mineral precipitation, to identify the minerals formed and to analyze the arsenic binding environment in the precipitates. Microcosm and rice pot experiments are set-up with arsenic-contaminated rice paddy soil. The microorganisms (either the native microbial population or the soil amended with the nitrate-dependent iron(II)-oxidizing Acidovorax sp. strain BoFeN1) are stimulated either with iron(II), nitrate, or oxygen. Dissolved and solid-phase arsenic and iron are quantified. Iron and arsenic speciation and redox state in batch and microcosm experiments are determined by LC-ICP-MS and synchrotron-based methods (EXAFS, XANES).

  9. Impaired arsenic metabolism in children during weaning

    International Nuclear Information System (INIS)

    Faengstroem, Britta; Hamadani, Jena; Nermell, Barbro; Grander, Margaretha; Palm, Brita; Vahter, Marie

    2009-01-01

    Background: Methylation of inorganic arsenic (iAs) via one-carbon metabolism is a susceptibility factor for a range of arsenic-related health effects, but there is no data on the importance of arsenic metabolism for effects on child development. Aim: To elucidate the development of arsenic metabolism in early childhood. Methods: We measured iAs, methylarsonic acid (MA) and dimethylarsinic acid (DMA), the metabolites of iAs, in spot urine samples of 2400 children at 18 months of age. The children were born to women participating in a population-based longitudinal study of arsenic effects on pregnancy outcomes and child development, carried out in Matlab, a rural area in Bangladesh with a wide range of arsenic concentrations in drinking water. Arsenic metabolism was evaluated in relation to age, sex, anthropometry, socio-economic status and arsenic exposure. Results: Arsenic concentrations in child urine (median 34 μg/L, range 2.4-940 μg/L), adjusted to average specific gravity of 1.009 g/mL, were considerably higher than that measured at 3 months of age, but lower than that in maternal urine. Child urine contained on average 12% iAs, 9.4% MA and 78% DMA, which implies a marked change in metabolite pattern since infancy. In particular, there was a marked increase in urinary %MA, which has been associated with increased risk of health effects. Conclusion: The arsenic metabolite pattern in urine of children at 18 months of age in rural Bangladesh indicates a marked decrease in arsenic methylation efficiency during weaning.

  10. Arsenic Hyperaccumulation Strategies: An Overview

    Directory of Open Access Journals (Sweden)

    Zahra Souri

    2017-07-01

    Full Text Available Arsenic (As pollution, which is on the increase around the world, poses a growing threat to the environment. Phytoremediation, an important green technology, uses different strategies, including As uptake, transport, translocation, and detoxification, to remediate this metalloid. Arsenic hyperaccumulator plants have developed various strategies to accumulate and tolerate high concentrations of As. In these plants, the formation of AsIII complexes with GSH and phytochelatins and their transport into root and shoot vacuoles constitute important mechanisms for coping with As stress. The oxidative stress induced by reactive oxygen species (ROS production is one of the principal toxic effects of As; moreover, the strong antioxidative defenses in hyperaccumulator plants could constitute an important As detoxification strategy. On the other hand, nitric oxide activates antioxidant enzyme and phytochelatins biosynthesis which enhances As stress tolerance in plants. Although several studies have focused on transcription, metabolomics, and proteomic changes in plants induced by As, the mechanisms involved in As transport, translocation, and detoxification in hyperaccumulator plants need to be studied in greater depth. This review updates recent progress made in the study of As uptake, translocation, chelation, and detoxification in As hyperaccumulator plants.

  11. Arsenic Accumulation by Pteris vittata L. in Two Chemically Variant Soils Treated with Arsenical Pesticides - Greenhouse Study

    Science.gov (United States)

    Therapong, C.; Datta, R.; Sarkar, D.; Pachanoor, D.

    2006-05-01

    Arsenic (As) is one of the most toxic elements present in the environment. Over the years, arsenic has found its way to the environment due to its extensive use in agriculture and in industrial practices as pesticides, fertilizers, wood preservatives, smelter wastes and coal combustion ash, all of which are of great environmental concern. Arsenic contamination affects biological activities because it is a carcinogen and a mutagen, which has detrimental effects on the immune system of animals. Remediation of arsenic-contaminated soils has become a major environmental issue in the recent years. Several physical and chemical treatment methods, such as soil washing, co-precipitation, and excavation, have used to remediate As, but all of these methods are rather expensive and can disturb soil physiology and ecology. Phytoremediation, a plant based technology for the removal of toxic contaminants from soil and water is an attractive approach. Of late, this technology has received a high degree of attention from the scientific community because it is environment-friendly and also because of its tremendous cost efficiency compared to the conventional methods. Chinese Brake Fern (Pteris vittata L.) is a known arsenic hyperaccumulator that is being used extensively at present to remove As from soils. However, the degree of efficiency of this plant in accumulating As is likely to be a function of the soil properties. The objective of the reported study was to investigate arsenic uptake by Chinese Brake Fern in As-contaminated soils from the Immokalee (acid sand with minimal As-retention potential) and Millhopper series (sandy loam with high Fe/Al content, hence, high As-retention potential). A greenhouse experiment was designed to evaluate the effects on As uptake by Chinese Brake Fern at two pesticide application rates: 225 mg/kg and 500 mg/kg As in two chemical forms, namely sodium arsenate (AsV) and dimethylarsinic acid (DMA). Each treatment was replicated three times in

  12. Assessment of global industrial-age anthropogenic arsenic contamination.

    Science.gov (United States)

    Han, Fengxiang X; Su, Yi; Monts, David L; Plodinec, M John; Banin, Amos; Triplett, Glover E

    2003-09-01

    Arsenic, a carcinogenic trace element, threatens not only the health of millions of humans and other living organisms, but also global sustainability. We present here, for the first time, the global industrial-age cumulative anthropogenic arsenic production and its potential accumulation and risks in the environment. In 2000, the world cumulative industrial-age anthropogenic arsenic production was 4.53 million tonnes. The world-wide coal and petroleum industries accounted for 46% of global annual gross arsenic production, and their overall contribution to industrial-age gross arsenic production was 27% in 2000. Global industrial-age anthropogenic As sources (as As cumulative production) follow the order: As mining production>As generated from coal>As generated from petroleum. The potential industrial-age anthropogenic arsenic input in world arable surface in 2000 was 2.18 mg arsenic kg(-1), which is 1.2 times that in the lithosphere. The development of substitute materials for arsenic applications in the agricultural and forestry industries and controls of arsenic emissions from the coal industry may be possible strategies to significantly decrease arsenic pollution sources and dissipation rates into the environment.

  13. Titanium dioxide nanoparticles enhance inorganic arsenic bioavailability and methylation in two freshwater algae species.

    Science.gov (United States)

    Luo, Zhuanxi; Wang, Zhenhong; Yan, Yameng; Li, Jinli; Yan, Changzhou; Xing, Baoshan

    2018-07-01

    The effect of titanium dioxide nanoparticles (nano-TiO 2 ) on the bioaccumulation and biotransformation of arsenic (As) remains largely unknown. In this study, we exposed two freshwater algae (Microcystis aeruginosa and Scenedesmus obliquus) to inorganic As (arsenite and arsenate) with the aim of increasing our understanding on As bioaccumulation and methylation in the presence of nano-TiO 2 . Direct evidence from transmission electron microscope (TEM) images show that nano-TiO 2 (anatase) entered exposed algae. Thus, nano-TiO 2 as carriers boosted As accumulation and methylation in these two algae species, which varied between inorganic As speciation and algae species. Specifically, nano-TiO 2 could markedly enhance arsenate (As(V)) accumulation in M. aeruginosa and arsenite (As(III)) accumulation in S. obliquus. Similarly, we found evidence of higher As methylation activity in the M. aeruginosa of As(III) 2 mg L -1 nano-TiO 2 treatment. Although this was also true for the S. obliquus (As(V)) treatment, this species exhibited higher As methylation compared to M. aeruginosa, being more sensitive to As associated with nano-TiO 2 compared to M. aeruginosa. Due to changes in pH levels inside these exposed algae, As dissociation from nano-TiO 2 inside algal cells enhanced As methylation. Accordingly, the potential influence of nanoparticles on the bioaccumulation and biotransformation of their co-contaminants deserves more attention. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. ARSENIC REMOVAL BY PHYTOFILTRATION AND SILICON TREATMENT : A POTENTIAL SOLUTION FOR LOWERING ARSENIC CONCENTRATIONS IN FOOD CROPS

    OpenAIRE

    Sandhi, Arifin

    2017-01-01

    Use of arsenic-rich groundwater for crop irrigation can increase the arsenic (As) content in food crops and act as a carcinogen, compromising human health. Using aquatic plant based phytofiltration is a potential eco-technique for removing arsenic from water. The aquatic moss species Warnstorfia fluitans grows naturally in mining areas in northern Sweden, where high concentrations of arsenic occur in lakes and rivers. This species was selected as a model for field, climate chamber and greenho...

  15. Arsenic and human health effects: A review.

    Science.gov (United States)

    Abdul, Khaja Shameem Mohammed; Jayasinghe, Sudheera Sammanthi; Chandana, Ediriweera P S; Jayasumana, Channa; De Silva, P Mangala C S

    2015-11-01

    Arsenic (As) is ubiquitous in nature and humans being exposed to arsenic via atmospheric air, ground water and food sources are certain. Major sources of arsenic contamination could be either through geological or via anthropogenic activities. In physiological individuals, organ system is described as group of organs that transact collectively and associate with other systems for conventional body functions. Arsenic has been associated with persuading a variety of complications in body organ systems: integumentary, nervous, respiratory, cardiovascular, hematopoietic, immune, endocrine, hepatic, renal, reproductive system and development. In this review, we outline the effects of arsenic on the human body with a main focus on assorted organ systems with respective disease conditions. Additionally, underlying mechanisms of disease development in each organ system due to arsenic have also been explored. Strikingly, arsenic has been able to induce epigenetic changes (in utero) and genetic mutations (a leading cause of cancer) in the body. Occurrence of various arsenic induced health effects involving emerging areas such as epigenetics and cancer along with their respective mechanisms are also briefly discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Role of complex organic arsenicals in food in aggregate exposure to arsenic

    Science.gov (United States)

    For much of the world’s population, food is the major source of exposure to arsenic. Exposure to this non-essential metalloid at relatively low levels has been linked to a wide range of adverse health effects. Thus, evaluating foods as sources of exposure to arsenic is important ...

  17. ARSENIC INTERACTION WITH IRON (II, III) HYDROXYCARBONATE GREEN RUST: IMPLICATIONS FOR ARSENIC REMEDIATION

    Science.gov (United States)

    Zerovalent iron is being used in permeable reactive barriers (PRBs) to remediate groundwater arsenic contamination. Iron(II, III) hydroxycarbonate green rust is a major corrosion product of zerovalent iron under anaerobic conditions. The interaction between arsenic and this green...

  18. Arbuscular mycorrhiza and their effect on the soil structure in farms with agroecological and intensive management

    Directory of Open Access Journals (Sweden)

    Juan David Lozano Sánchez

    2015-10-01

    Full Text Available Arbuscular mycorrhizal fungi help to reduce the damage caused by erosion and maintain soil structure through the production of mycelium and adhering substances. This study evaluated the structural stability; estimated the diversity and density of mycorrhizal spores present in three systems of soil (eroded, forest and coffee plantations in the rural area of Dagua, Valle del Cauca, Colombia. The systems evaluated were classified as farms with intensive or agroecological management. There were 25 morphospecies of mycorrhiza grouped in 13 genera, being Glomus and Entrophospora the most representative. The mean index values of mean weight (DPM and geometric (DGM diameters and diversity of mycorrhizal spores were statistically higher in farms with agroecological management than in farms with intensive management. The aggregate stability analysis revealed that eroded soils have significantly lower stability than forest and crop soils. A statistically significant correlation was found between diversity (r = 0.579 and spore density (r = 0.66 regarding DGM, and DPM with Shannon diversity (r = 0.54. Differences in practices, use and soil management affect mycorrhizal diversity found on farms and its effect such as particle aggregation agent generates remarkable changes in the stability and soil structure of evaluated areas. It is concluded, that agroecological management tends to favour both mycorrhizae and the structure of soils.

  19. Distribution and speciation of arsenic by transplacental and early life exposure to inorganic arsenic in offspring rats.

    Science.gov (United States)

    Xi, Shuhua; Jin, Yaping; Lv, Xiuqiang; Sun, Guifan

    2010-04-01

    The amount of arsenic compounds was determined in the liver and brain of pups and in breast milk in the pup's stomach in relation to the route of exposure: transplacental, breast milk, or drinking water. Forty-eight pregnant rats were randomly divided into four groups, each group was given free access to drinking water that contained 0, 10, 50, and 100 mg/L NaAsO(2) from gestation day 6 (GD 6) until postnatal day 42 (PND 42). Once pups were weaned, they started to drink the same arsenic-containing water as the dams. Contents of inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and trimethylarsenic acid (TMA) in livers and brains of the pups on PND 0, 15, 28, and 42 and breast milk taken from the pup's stomach on PND 0 and 15 were detected using the hydride generation atomic absorption spectroscopy method. Concentrations of iAs, MMA, and DMA in the breast milk, the brain, and the liver of the pups increased with the concentration of arsenic in drinking water on PND 0, 15, 28, and 42. Compared to the liver or brain, breast milk had the lowest arsenic concentrations. There was a significant decrease in the levels of arsenic species on PND 15 compared to PND 0, 28, or 42. It was confirmed that arsenic species can pass through the placental barrier from dams to offspring and across the blood-brain barrier in the pups, and breast milk from dams exposed to arsenic in drinking water contains less arsenic than the liver and brain of pups.

  20. Toxic Substances Portal- Arsenic

    Science.gov (United States)

    ... is found at low levels in breast milk. top How can families reduce their risk for exposure to arsenic? If you use arsenic-treated wood in home projects, you should wear dust masks, gloves, and protective clothing to decrease exposure to sawdust. ...

  1. Arsenical poisoning of racehorses

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, G.N.; Fawell, E.V.; Brown, J.K.

    1964-03-07

    A case of arsenic poisoning in a training stable of Thoroughbred racehorses is described. This was due to the accidental spilling of an arsenical rat poison into the corn bin. Nine horses were affected. The mortality rate was 100 per cent. 1 table.

  2. Arsenic removal for ceramic water filters

    Directory of Open Access Journals (Sweden)

    Mishant Kumar

    2013-02-01

    Full Text Available Arsenic in drinking water is a hazard to human health and is a known carcinogen (Mass 1992. Resource Development International – Cambodia (RDIC has researched, developed, and manufactured simple ceramic water fi lters (CWF which have proved to be extremely effective in removing pathogens from water. These fi lters however, do not remove arsenic from water, which exists in the source water at levels above the World Health Organisation (WHO guideline of 10μg/L. The aims of this literature based study were to investigate conventional and non-conventional arsenic removal processes, and to discuss the options for applying an arsenic removal technology to the CWFs produced by RDIC. It was found that conventional arsenic removal technologies are diffi cult to implement in the context of household water treatment in a developing country. This study suggested that non-conventional arsenic removal technologies shall be more effective and that field studies must be undertaken to verify the success of such methods.

  3. Unfolded protein response (UPR) signaling regulates arsenic trioxide-mediated macrophage innate immune function disruption

    International Nuclear Information System (INIS)

    Srivastava, Ritesh K.; Li, Changzhao; Chaudhary, Sandeep C.; Ballestas, Mary E.; Elmets, Craig A.; Robbins, David J.; Matalon, Sadis; Deshane, Jessy S.; Afaq, Farrukh; Bickers, David R.; Athar, Mohammad

    2013-01-01

    Arsenic exposure is known to disrupt innate immune functions in humans and in experimental animals. In this study, we provide a mechanism by which arsenic trioxide (ATO) disrupts macrophage functions. ATO treatment of murine macrophage cells diminished internalization of FITC-labeled latex beads, impaired clearance of phagocytosed fluorescent bacteria and reduced secretion of pro-inflammatory cytokines. These impairments in macrophage functions are associated with ATO-induced unfolded protein response (UPR) signaling pathway characterized by the enhancement in proteins such as GRP78, p-PERK, p-eIF2α, ATF4 and CHOP. The expression of these proteins is altered both at transcriptional and translational levels. Pretreatment with chemical chaperon, 4-phenylbutyric acid (PBA) attenuated the ATO-induced activation in UPR signaling and afforded protection against ATO-induced disruption of macrophage functions. This treatment also reduced ATO-mediated reactive oxygen species (ROS) generation. Interestingly, treatment with antioxidant N-acetylcysteine (NAC) prior to ATO exposure, not only reduced ROS production and UPR signaling but also improved macrophage functions. These data demonstrate that UPR signaling and ROS generation are interdependent and are involved in the arsenic-induced pathobiology of macrophage. These data also provide a novel strategy to block the ATO-dependent impairment in innate immune responses. - Highlights: • Inorganic arsenic to humans and experimental animals disrupt innate immune responses. • The mechanism underlying arsenic impaired macrophage functions involves UPR signaling. • Chemical chaperon attenuates arsenic-mediated macrophage function impairment. • Antioxidant, NAC blocks impairment in arsenic-treated macrophage functions

  4. Unfolded protein response (UPR) signaling regulates arsenic trioxide-mediated macrophage innate immune function disruption

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, Ritesh K.; Li, Changzhao; Chaudhary, Sandeep C. [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, Birmingham, AL (United States); Ballestas, Mary E. [Department of Pediatrics Infectious Disease, Children' s of Alabama, School of Medicine, University of Alabama at Birmingham, AL (United States); Elmets, Craig A. [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, Birmingham, AL (United States); Robbins, David J. [Department of Surgery, Molecular Oncology Program, Miller School of Medicine, University of Miami, Miami (United States); Matalon, Sadis [Department of Anesthesiology, University of Alabama at Birmingham, Birmingham, AL (United States); Deshane, Jessy S. [Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, AL (United States); Afaq, Farrukh [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, Birmingham, AL (United States); Bickers, David R. [Department of Dermatology, Columbia University Medical Center, New York (United States); Athar, Mohammad, E-mail: mathar@uab.edu [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, Birmingham, AL (United States)

    2013-11-01

    Arsenic exposure is known to disrupt innate immune functions in humans and in experimental animals. In this study, we provide a mechanism by which arsenic trioxide (ATO) disrupts macrophage functions. ATO treatment of murine macrophage cells diminished internalization of FITC-labeled latex beads, impaired clearance of phagocytosed fluorescent bacteria and reduced secretion of pro-inflammatory cytokines. These impairments in macrophage functions are associated with ATO-induced unfolded protein response (UPR) signaling pathway characterized by the enhancement in proteins such as GRP78, p-PERK, p-eIF2α, ATF4 and CHOP. The expression of these proteins is altered both at transcriptional and translational levels. Pretreatment with chemical chaperon, 4-phenylbutyric acid (PBA) attenuated the ATO-induced activation in UPR signaling and afforded protection against ATO-induced disruption of macrophage functions. This treatment also reduced ATO-mediated reactive oxygen species (ROS) generation. Interestingly, treatment with antioxidant N-acetylcysteine (NAC) prior to ATO exposure, not only reduced ROS production and UPR signaling but also improved macrophage functions. These data demonstrate that UPR signaling and ROS generation are interdependent and are involved in the arsenic-induced pathobiology of macrophage. These data also provide a novel strategy to block the ATO-dependent impairment in innate immune responses. - Highlights: • Inorganic arsenic to humans and experimental animals disrupt innate immune responses. • The mechanism underlying arsenic impaired macrophage functions involves UPR signaling. • Chemical chaperon attenuates arsenic-mediated macrophage function impairment. • Antioxidant, NAC blocks impairment in arsenic-treated macrophage functions.

  5. Arsenic

    Science.gov (United States)

    ... for drinking-water quality Chemical hazards in drinking-water: arsenic Evaluations of the Joint FAO/WHO Expert Committee ... Africa Americas South-East Asia Europe Eastern Mediterranean Western ...

  6. Effect of Fluoride on Arsenic Uptake from Arsenic-Contaminated Groundwater using Pteris vittata L.

    Science.gov (United States)

    Zhao, Junying; Guo, Huaming; Ma, Jie; Shen, Zhaoli

    2015-01-01

    High-arsenic groundwater in inland basins usually contains high concentrations of fluoride. In the present study, the effects of fluoride on arsenic uptake by Pteris vittata and on arsenic transformation in growth media were investigated under greenhouse conditions. After P. vittata was hydroponically exposed to 66.8 μM As (V) in the presence of 1.05 mM F- in the form of NaF, KF, or NaF+KF for 10 d, no visible toxicity symptoms were observed, and there were not significant differences in the dry biomass among the four treatments. The results showed that P. vittata tolerated F- concentrations as high as 1.05 mM but did not accumulate fluoride in their own tissues. Arsenic uptake was inhibited in the presence of 1.05 mM F-. However, in hydroponic batches with 60 μM As (III) or 65 μM As (V), it was found that 210.6 and 316.0 μM F(-) promoted arsenic uptake. As(III) was oxidized to As(V) in the growth media in the presence and absence of plants, and F- had no effect on the rate of As(III) transformation. These experiments demonstrated that P. vittata was a good candidate to remediate arsenic-contaminated groundwater in the presence of fluoride. Our results can be used to develop strategies to remediate As-F-contaminated water using P. vittata.

  7. Arsenic in tube well water in Bangladesh: health and economic impacts and implications for arsenic mitigation.

    Science.gov (United States)

    Flanagan, Sara V; Johnston, Richard B; Zheng, Yan

    2012-11-01

    A national drinking water quality survey conducted in 2009 furnished data that were used to make an updated estimate of chronic arsenic exposure in Bangladesh. About 20 million and 45 million people were found to be exposed to concentrations above the national standard of 50 µg/L and the World Health Organization's guideline value of 10 µg/L, respectively. From the updated exposure data and all-cause mortality hazard ratios based on local epidemiological studies, it was estimated that arsenic exposures to concentrations > 50 µg/L and 10-50 µg/L account for an annual 24,000 and perhaps as many as 19,000 adult deaths in the country, respectively. Exposure varies widely in the 64 districts; among adults, arsenic-related deaths account for 0-15% of all deaths. An arsenic-related mortality rate of 1 in every 16 adult deaths could represent an economic burden of 13 billion United States dollars (US$) in lost productivity alone over the next 20 years. Arsenic mitigation should follow a two-tiered approach: (i) prioritizing provision of safe water to an estimated 5 million people exposed to > 200 µg/L arsenic, and (ii) building local arsenic testing capacity. The effectiveness of such an approach was demonstrated during the United Nations Children's Fund 2006-2011 country programme, which provided safe water to arsenic-contaminated areas at a cost of US$ 11 per capita. National scale-up of such an approach would cost a few hundred million US dollars but would improve the health and productivity of the population, especially in future generations.

  8. Arsenic removal by manganese greensand filters

    Energy Technology Data Exchange (ETDEWEB)

    Phommavong, T. [Saskatchewan Environment, Regina (Canada); Viraraghavan, T. [Univ. of Regina, Saskatchewan (Canada). Faculty of Engineering

    1994-12-31

    Some of the small communities in Saskatchewan are expected to have difficulty complying with the new maximum acceptable concentration (MAC) of 25 {micro}g/L for arsenic. A test column was set up in the laboratory to study the removal of arsenic from the potable water using oxidation with KMnO{sub 4}, followed by manganese greensand filtration. Tests were run using water from the tap having a background arsenic concentration of <0.5 {micro}g/L and iron concentration in the range of 0.02 to 0.77 mg/L. The test water was spiked with arsenic and iron. Results showed that 61 % to 98% of arsenic can be removed from the potable water by oxidation with KMnO{sub 4} followed by manganese greensand filtration.

  9. The co-occurrence and morphological continuum between ericoid mycorrhiza and dark septate endophytes in roots of six European Rhododendron species

    Czech Academy of Sciences Publication Activity Database

    Vohník, Martin; Albrechtová, Jana

    2011-01-01

    Roč. 46, č. 4 (2011), s. 373-386 ISSN 1211-9520 R&D Projects: GA ČR GP206/09/P340 Institutional research plan: CEZ:AV0Z60050516 Keywords : ericoid mycorrhiza * dark septate endophytes * rhododendrons Subject RIV: EF - Botanics Impact factor: 1.500, year: 2011

  10. Maternal Arsenic Exposure, Arsenic Methylation Efficiency, and Birth Outcomes in the Biomarkers of Exposure to ARsenic (BEAR) Pregnancy Cohort in Mexico

    Science.gov (United States)

    Laine, Jessica E.; Bailey, Kathryn A.; Rubio-Andrade, Marisela; Olshan, Andrew F.; Smeester, Lisa; Drobná, Zuzana; Herring, Amy H.; Stýblo, Miroslav; García-Vargas, Gonzalo G.

    2014-01-01

    Background: Exposure to inorganic arsenic (iAs) from drinking water is a global public health problem, yet much remains unknown about the extent of exposure in susceptible populations. Objectives: We aimed to establish the Biomarkers of Exposure to ARsenic (BEAR) prospective pregnancy cohort in Gómez Palacio, Mexico, to better understand the effects of iAs exposure on pregnant women and their children. Methods: Two hundred pregnant women were recruited for this study. Concentrations of iAs in drinking water (DW-iAs) and maternal urinary concentrations of iAs and its monomethylated and dimethylated metabolites (MMAs and DMAs, respectively) were determined. Birth outcomes were analyzed for their relationship to DW-iAs and to the concentrations and proportions of maternal urinary arsenicals. Results: DW-iAs for the study subjects ranged from iAs that exceeded the World Health Organization’s recommended guideline of 10 μg As/L. DW-iAs was significantly associated with the sum of the urinary arsenicals (U-tAs). Maternal urinary concentrations of MMAs were negatively associated with newborn birth weight and gestational age. Maternal urinary concentrations of iAs were associated with lower mean gestational age and newborn length. Conclusions: Biomonitoring results demonstrate that pregnant women in Gómez Palacio are exposed to potentially harmful levels of DW-iAs. The data support a relationship between iAs metabolism in pregnant women and adverse birth outcomes. The results underscore the risks associated with iAs exposure in vulnerable populations. Citation: Laine JE, Bailey KA, Rubio-Andrade M, Olshan AF, Smeester L, Drobná Z, Herring AH, Stýblo M, García-Vargas GG, Fry RC. 2015. Maternal arsenic exposure, arsenic methylation efficiency, and birth outcomes in the Biomarkers of Exposure to ARsenic (BEAR) pregnancy cohort in Mexico. Environ Health Perspect 123:186–192; http://dx.doi.org/10.1289/ehp.1307476 PMID:25325819

  11. The beneficial effect of dual inoculation of vesicular-arbuscular mycorrhizae + rhizobium on growth of white clover

    OpenAIRE

    Lin, XG.; Hao, WY.; Wu, TH.

    1993-01-01

    Investigation on the effect of phosphorus on vesicular-arbuscular mycorrhizal infection, and dual inoculation of vesicular-arbuscular mycorrhizae + rhizobium on growth of white clover under field microplots and pot experiments was conducted on fluvo-aquic soils of semi-arid region in north China. The results showed that 60 kg P205 ha in form of superphosphate was the most favorable phosphorus level for vesicular-arbuscular mycorrhizal infection ; mycorrhizal infection, nodulation, dry weight ...

  12. Inhibition of insulin-dependent glucose uptake by trivalent arsenicals: possible mechanism of arsenic-induced diabetes

    International Nuclear Information System (INIS)

    Walton, Felecia S.; Harmon, Anne W.; Paul, David S.; Drobna, Zuzana; Patel, Yashomati M.; Styblo, Miroslav

    2004-01-01

    Chronic exposures to inorganic arsenic (iAs) have been associated with increased incidence of noninsulin (type-2)-dependent diabetes mellitus. Although mechanisms by which iAs induces diabetes have not been identified, the clinical symptoms of the disease indicate that iAs or its metabolites interfere with insulin-stimulated signal transduction pathway or with critical steps in glucose metabolism. We have examined effects of iAs and methylated arsenicals that contain trivalent or pentavalent arsenic on glucose uptake by 3T3-L1 adipocytes. Treatment with inorganic and methylated pentavalent arsenicals (up to 1 mM) had little or no effect on either basal or insulin-stimulated glucose uptake. In contrast, trivalent arsenicals, arsenite (iAs III ), methylarsine oxide (MAs III O), and iododimethylarsine (DMAs III O) inhibited insulin-stimulated glucose uptake in a concentration-dependent manner. Subtoxic concentrations of iAs III (20 μM), MAs III O (1 μM), or DMAs III I (2 μM) decreased insulin-stimulated glucose uptake by 35-45%. Basal glucose uptake was significantly inhibited only by cytotoxic concentrations of iAs III or MAs III O. Examination of the components of the insulin-stimulated signal transduction pathway showed that all trivalent arsenicals suppressed expression and possibly phosphorylation of protein kinase B (PKB/Akt). The concentration of an insulin-responsive glucose transporter (GLUT4) was significantly lower in the membrane region of 3T3-L1 adipocytes treated with trivalent arsenicals as compared with untreated cells. These results suggest that trivalent arsenicals inhibit insulin-stimulated glucose uptake by interfering with the PKB/Akt-dependent mobilization of GLUT4 transporters in adipocytes. This mechanism may be, in part, responsible for the development of type-2 diabetes in individuals chronically exposed to iAs

  13. Arsenic, microbes and contaminated aquifers

    Science.gov (United States)

    Oremland, Ronald S.; Stolz, John F.

    2005-01-01

    The health of tens of millions of people world-wide is at risk from drinking arsenic-contaminated well water. In most cases this arsenic occurs naturally within the sub-surface aquifers, rather than being derived from identifiable point sources of pollution. The mobilization of arsenic into the aqueous phase is the first crucial step in a process that eventually leads to human arsenicosis. Increasing evidence suggests that this is a microbiological phenomenon.

  14. ARSENIC CONTAMINATION IN GROUNDWATER: A STATISTICAL MODELING

    Directory of Open Access Journals (Sweden)

    Palas Roy

    2013-01-01

    Full Text Available High arsenic in natural groundwater in most of the tubewells of the Purbasthali- Block II area of Burdwan district (W.B, India has recently been focused as a serious environmental concern. This paper is intending to illustrate the statistical modeling of the arsenic contaminated groundwater to identify the interrelation of that arsenic contain with other participating groundwater parameters so that the arsenic contamination level can easily be predicted by analyzing only such parameters. Multivariate data analysis was done with the collected groundwater samples from the 132 tubewells of this contaminated region shows that three variable parameters are significantly related with the arsenic. Based on these relationships, a multiple linear regression model has been developed that estimated the arsenic contamination by measuring such three predictor parameters of the groundwater variables in the contaminated aquifer. This model could also be a suggestive tool while designing the arsenic removal scheme for any affected groundwater.

  15. Use of Endophytic and Rhizosphere Bacteria To Improve Phytoremediation of Arsenic-Contaminated Industrial Soils by Autochthonous Betula celtiberica

    OpenAIRE

    Mesa, Victoria; Navazas, Alejandro; Gonzalez-Gil, Ricardo; Gonzalez, Aida; Weyens, Nele; Lauga, Beatrice; Gallego, Jose Luis R.; Sanchez, Jesus; Isabel Pelaez, Ana

    2017-01-01

    The aim of this study was to investigate the potential of indigenous arsenic-tolerant bacteria to enhance arsenic phytoremediation by the autochthonous pseudometallophyte Betula celtiberica. The first goal was to perform an initial analysis of the entire rhizosphere and endophytic bacterial communities of the above-named accumulator plant, including the cultivable bacterial species. B. celtiberica's microbiome was dominated by taxa related to Flavobacteriales, Burkholderiales, and Pseudomonad...

  16. Oxidative stress and hepatic stellate cell activation are key events in arsenic induced liver fibrosis in mice

    International Nuclear Information System (INIS)

    Ghatak, Subhadip; Biswas, Ayan; Dhali, Gopal Krishna; Chowdhury, Abhijit; Boyer, James L.; Santra, Amal

    2011-01-01

    Arsenic is an environmental toxicant and carcinogen. Exposure to arsenic is associated with development of liver fibrosis and portal hypertension through ill defined mechanisms. We evaluated hepatic fibrogenesis after long term arsenic exposure in a murine model. BALB/c mice were exposed to arsenic by daily gavages of 6 μg/gm body weight for 1 year and were evaluated for markers of hepatic oxidative stress and fibrosis, as well as pro-inflammatory, pro-apoptotic and pro-fibrogenic factors at 9 and 12 months. Hepatic NADPH oxidase activity progressively increased in arsenic exposure with concomitant development of hepatic oxidative stress. Hepatic steatosis with occasional collection of mononuclear inflammatory cells and mild portal fibrosis were the predominant liver lesion observed after 9 months of arsenic exposure, while at 12 months, the changes included mild hepatic steatosis, inflammation, necrosis and significant fibrosis in periportal areas. The pathologic changes in the liver were associated with markers of hepatic stellate cells (HSCs) activation, matrix reorganization and fibrosis including α-smooth muscle actin, transforming growth factor-β1, PDGF-Rβ, pro-inflammatory cytokines and enhanced expression of tissue inhibitor of metalloproteinase-1 and pro(α) collagen type I. Moreover, pro-apoptotic protein Bax was dominantly expressed and Bcl-2 was down-regulated along with increased number of TUNEL positive hepatocytes in liver of arsenic exposed mice. Furthermore, HSCs activation due to increased hepatic oxidative stress observed after in vivo arsenic exposure was recapitulated in co-culture model of isolated HSCs and hepatocytes exposed to arsenic. These findings have implications not only for the understanding of the pathology of arsenic related liver fibrosis but also for the design of preventive strategies in chronic arsenicosis.

  17. Distribution of Arsenic and Risk Assessment of Activities on Soccer Pitches Irrigated with Arsenic-Contaminated Water

    Directory of Open Access Journals (Sweden)

    Nadia Martínez-Villegas

    2018-05-01

    Full Text Available The aim of this research was to estimate the risk of human exposure to arsenic due to sporting activities in a private soccer club in Mexico, where arsenic-contaminated water was regularly used for irrigation. For this purpose, the total concentration in the topsoil was considered for risk assessment. This was accomplished through three main objectives: (1 measuring arsenic concentrations in irrigation water and irrigated soils, (2 determining arsenic spatial distribution in shallow soils with Geographical Information Systems (GIS using geostatistical analysis, and (3 collecting field and survey data to develop a risk assessment calculation for soccer activities in the soccer club. The results showed that the average arsenic concentrations in shallow soils (138.1 mg/kg were 6.2 times higher than the Mexican threshold for domestic soils (22 mg/kg. Furthermore, dermal contact between exposed users and contaminated soils accounted for a maximum carcinogenic risk value of 1.8 × 10−5, which is one order of magnitude higher than the recommended risk value, while arsenic concentrations in the irrigation water were higher (6 mg/L than the WHO’s permissible threshold in drinking water, explaining the contamination of soils after irrigation. To the best of our knowledge, this is the first risk study regarding dermal contact with arsenic following regular grass irrigation with contaminated water in soccer pitches.

  18. Certain cases of poisoning by arsenic

    Energy Technology Data Exchange (ETDEWEB)

    Cristol, P; Fourcade, J; Ravoire, J; Bezenech, C

    1939-05-01

    Cases of acute and chronic poisoning by arsenic are reported. Diffuse pains, angor, edema of the limbs and genitals, complicated by heptic insufficiency and chronic bronchitis were determined in a subject having lived near an industrial plant processing arseniferous ores for several years. The plant emitted several hundred kg of finely dispersed arsenic oxide daily which settled on forage and vegetables. Symptoms of poisoning by arsenic were also detected in cattle in the same area. The installation of Cottrell type dust separators has helped to suppress the arsenic oxide emissions.

  19. Application of 32P to investigate Mycorrhiza and streptomyces efficiency in wheat (Triticum aestivum) at various levels of phosphorus

    International Nuclear Information System (INIS)

    Ardakani, M.R.; Majid, F.; Mazaheri, D.; Naseri Tafti, M.; Nour Mohammad, G.

    2004-01-01

    In order to study the symbiosis of Mycorrhiza and Streptomyes from actinomycetes with the roots of wheat as bio fertilizers that could provide plant nutrients and plant protection, a research was established with different levels of phosphorus under greenhouse conditions. On the other hand, the interaction of two microorganisms, to achieve a good fertilization formula, was also studied. To obtain precise results, 32 P was utilized. A factorial experiment in a completely randomized design with 3 replications was used in which 4 levels of P(0, 0.20, 0.40 and 0.60 g pot -1 ) were applied for each microorganism 2 levels (one with and one without using) in form of seed inoculation are used. Results showed that, using mycorrhiza had a positive and significant effect on all characters. By increasing the phosphorus levels, however, the mycorrhizal activity increased at 0.40 g pot-1 which indicated a good activity. There were negative or antagonistic interaction between two microorganisms and all characters were reduced by using them together. (author)

  20. Soil microbiology in land reclamation volume II - mycorrhizae

    Energy Technology Data Exchange (ETDEWEB)

    Graves, D.H. (ed.)

    1984-01-01

    This volume contains three separate reports: RRTAC 84-4 (Greenhouse pot studies dealing with amendment of oil sand tailings: effects of peat, sewage sludge and fertilizer on plant growth, mycorrhizae and microbial activity); RRTAC 84-8 (Vesicular-arbuscular mycorrhizal (VAM) development of slender wheatgrass on amended oil sand tailings and subalpine coal mines spoil); RRTAC 84-7 (Ectomycorrhizae in amended oil sand tailings and subalpine coal mine spoil and in undisturbed Jack pine and spruce stands). In the first report mixtures of two peats were used to amend oil sand tailings and either mineral fertilizers or sewage sludge were added at different rates. The growth of slender wheat grass and jack pine grown in the greenhouse in these media were monitored. In the second report the VAM development of slender wheatgrass was monitored over a 4 year period; in the third the mycorrhizal status of jack pine and bear berry grown in oil sand tailings treated with various amendments and of white spruce and willow grown in subalpine coal mine spoil were monitored over the same period.

  1. Urinary arsenic speciation profile in ethnic group of the Atacama desert (Chile) exposed to variable arsenic levels in drinking water.

    Science.gov (United States)

    Yáñez, Jorge; Mansilla, Héctor D; Santander, I Paola; Fierro, Vladimir; Cornejo, Lorena; Barnes, Ramón M; Amarasiriwardena, Dulasiri

    2015-01-01

    Ethnic groups from the Atacama Desert (known as Atacameños) have been exposed to natural arsenic pollution for over 5000 years. This work presents an integral study that characterizes arsenic species in water used for human consumption. It also describes the metabolism and arsenic elimination through urine in a chronically exposed population in northern Chile. In this region, water contained total arsenic concentrations up to 1250 μg L(-1), which was almost exclusively As(V). It is also important that this water was ingested directly from natural water sources without any treatment. The ingested arsenic was extensively methylated. In urine 93% of the arsenic was found as methylated arsenic species, such as monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)]. The original ingested inorganic species [As(V)], represent less than 1% of the total urinary arsenic. Methylation activity among individuals can be assessed by measuring primary [inorganic As/methylated As] and secondary methylation [MMA/DMA] indexes. Both methylation indexes were 0.06, indicating a high biological converting capability of As(V) into MMA and then MMA into DMA, compared with the control population and other arsenic exposed populations previously reported.

  2. Arsenic burden survey among refuse incinerator workers

    Directory of Open Access Journals (Sweden)

    Chao Chung-Liang

    2005-01-01

    Full Text Available Background: Incinerator workers are not considered to have arsenic overexposure although they have the risk of overexposure to other heavy metals. Aim: To examine the relationship between arsenic burden and risk of occupational exposure in employees working at a municipal refuse incinerator by determining the concentrations of arsenic in the blood and urine. Settings and Design: The workers were divided into three groups based on their probability of contact with combustion-generated residues, namely Group 1: indirect contact, Group 2: direct contact and Group 3: no contact. Healthy age- and sex-matched residents living in the vicinity were enrolled as the control group. Materials and Methods: Heavy metal concentrations were measured by atomic absorption spectrophotometer. Downstream rivers and drinking water of the residents were examined for environmental arsenic pollution. A questionnaire survey concerning the contact history of arsenic was simultaneously conducted. Statistical analysis: Non-parametric tests, cross-tabulation and multinomial logistic regression. Results: This study recruited 122 incinerator workers. The urine and blood arsenic concentrations as well as incidences of overexposure were significantly higher in the workers than in control subjects. The workers who had indirect or no contact with combustion-generated residues had significantly higher blood arsenic level. Arsenic contact history could not explain the difference. Airborne and waterborne arsenic pollution were not detected. Conclusion: Incinerator workers run the risk of being exposed to arsenic pollution, especially those who have incomplete protection in the workplace even though they only have indirect or no contact with combustion-generated pollutants.

  3. Interactions between arsenic species and marine algae

    Energy Technology Data Exchange (ETDEWEB)

    Sanders, J.G.

    1978-01-01

    The arsenic concentration and speciation of marine algae varies widely, from 0.4 to 23 ng.mg/sup -1/, with significant differences in both total arsenic content and arsenic speciation occurring between algal classes. The Phaeophyceae contain more arsenic than other algal classes, and a greater proportion of the arsenic is organic. The concentration of inorganic arsenic is fairly constant in macro-algae, and may indicate a maximum level, with the excess being reduced and methylated. Phytoplankton take up As(V) readily, and incorporate a small percentage of it into the cell. The majority of the As(V) is reduced, methylated, and released to the surrounding media. The arsenic speciation in phytoplankton and Valonia also changes when As(V) is added to cultures. Arsenate and phosphate compete for uptake by algal cells. Arsenate inhibits primary production at concentrations as low as 5 ..mu..g.1/sup -1/ when the phosphate concentration is low. The inhibition is competitive. A phosphate enrichment of > 0.3 ..mu..M alleviates this inhibition; however, the As(V) stress causes an increase in the cell's phosphorus requirement. Arsenite is also toxic to phytoplankton at similar concentrations. Methylated arsenic species did not affect cell productivity, even at concentrations of 25 ..mu..g.1/sup -1/. Thus, the methylation of As(V) by the cell produces a stable, non-reactive compound which is nontoxic. The uptake and subsequent reduction and methylation of As(V) is a significant factor in determining the arsenic biogeochemistry of productive systems, and also the effect that the arsenic may have on algal productivity. Therefore, the role of marine algae in determining the arsenic speciation of marine systems cannot be ignored. (ERB)

  4. Containing arsenic-enriched groundwater tracing lead isotopic compositions of common arsenical pesticides in a coastal Maine watershed

    Science.gov (United States)

    Ayuso, Robert A.; Foley, Nora K.; Robinson, Glipin R.; Colvin, A.S.; Lipfert, G.; Reeve, A.S.

    2006-01-01

    Arsenical pesticides and herbicides were extensively used on apple, blueberry, and potato crops in New England during the first half of the twentieth century. Lead arsenate was the most heavily used arsenical pesticide until it was officially banned. Lead arsenate, calcium arsenate, and sodium arsenate have similar Pb isotope compositions: 208Pb207Pb = 2.3839-2.4722, and 206Pb207Pb = 1.1035-1.2010. Other arsenical pesticides such as copper acetoarsenite (Paris green), methyl arsonic acid and methane arsonic acid, as well as arsanilic acid are widely variable in isotope composition. Although a complete understanding of the effects of historical use of arsenical pesticides is not available, initial studies indicate that arsenic and lead concentrations in stream sediments in New England are higher in agricultural areas that intensely used arsenical pesticides than in other areas. The Pb isotope compositions of pesticides partially overlap values of stream sediments from areas with the most extensive agricultural use. The lingering effects of arsenical pesticide use were tested in a detailed geochemical and isotopic study of soil profiles from a watershed containing arsenic-enriched ground water in coastal Maine. Acid-leach compositions of the soils represent lead adsorbed to mineral surfaces or held in soluble minerals (Fe- and Mn-hydroxides, carbonate, and some micaceous minerals), whereas residue compositions likely reflect bedrock compositions. The soil profiles contain labile Pb (acid-leach) showing a moderate range in 206Pb 207Pb (1.1870-1.2069), and 208Pb207Pb (2.4519-2.4876). Isotope values vary as a function of depth: the lowest Pb isotope ratios (e.g.,208Pb206Pb) representing labile lead are in the uppermost soil horizons. Lead contents decrease with depth in the soil profiles. Arsenic contents show no clear trend with depth. A multi-component mixing scheme that included lead from the local parent rock (Penobscot Formation), lead derived from combustion of

  5. First-principles studies of di-arsenic interstitial and its implications for arsenic-interstitial diffusion in crystalline silicon

    International Nuclear Information System (INIS)

    Kim, Yonghyun; Kirichenko, Taras A.; Kong, Ning; Larson, Larry; Banerjee, Sanjay K.

    2007-01-01

    We propose new structural configurations and novel diffusion mechanisms for neutral di-arsenic interstitial (As 2 I 2 ) in silicon with a first-principle density functional theory simulation within the generalized gradient approximation. With an assumption of excess silicon interstitials and high arsenic concentrations, neutral As 2 I 2 is expected to be favorable and mobile with low-migration barrier. Moreover, because the diffusion barrier of arsenic interstitial pairs (AsI) is very low ( 2 I 2 can be easily formed and likely intermediate stage of larger arsenic interstitial clusters

  6. The role of arbuscular mycorrhizas in reducing soil nutrient loss.

    Science.gov (United States)

    Cavagnaro, Timothy R; Bender, S Franz; Asghari, Hamid R; Heijden, Marcel G A van der

    2015-05-01

    Substantial amounts of nutrients are lost from soils via leaching and as gaseous emissions. These losses can be environmentally damaging and expensive in terms of lost agricultural production. Plants have evolved many traits to optimize nutrient acquisition, including the formation of arbuscular mycorrhizas (AM), associations of plant roots with fungi that acquire soil nutrients. There is emerging evidence that AM have the ability to reduce nutrient loss from soils by enlarging the nutrient interception zone and preventing nutrient loss after rain-induced leaching events. Until recently, this important ecosystem service of AM had been largely overlooked. Here we review the role of AM in reducing nutrient loss and conclude that this role cannot be ignored if we are to increase global food production in an environmentally sustainable manner. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Inorganic arsenic levels in baby rice are of concern

    International Nuclear Information System (INIS)

    Meharg, Andrew A.; Sun, Guoxin; Williams, Paul N.; Adomako, Eureka; Deacon, Claire; Zhu, Yong-Guan; Feldmann, Joerg; Raab, Andrea

    2008-01-01

    Inorganic arsenic is a chronic exposure carcinogen. Analysis of UK baby rice revealed a median inorganic arsenic content (n = 17) of 0.11 mg/kg. By plotting inorganic arsenic against total arsenic, it was found that inorganic concentrations increased linearly up to 0.25 mg/kg total arsenic, then plateaued at 0.16 mg/kg at higher total arsenic concentrations. Inorganic arsenic intake by babies (4-12 months) was considered with respect to current dietary ingestion regulations. It was found that 35% of the baby rice samples analysed would be illegal for sale in China which has regulatory limit of 0.15 mg/kg inorganic arsenic. EU and US food regulations on arsenic are non-existent. When baby inorganic arsenic intake from rice was considered, median consumption (expressed as μg/kg/d) was higher than drinking water maximum exposures predicted for adults in these regions when water intake was expressed on a bodyweight basis. - Median consumption of organic arsenic levels for UK babies from baby rice is above threshold considered safe

  8. Chronic arsenic poisoning following ayurvedic medication.

    Science.gov (United States)

    Pinto, Benzeeta; Goyal, Palvi; Flora, S J S; Gill, K D; Singh, Surjit

    2014-12-01

    Ayurveda, Indian traditional system of medicine, is practiced commonly in South East Asia and in many parts of the world. Many ayurvedic drugs contain heavy metals and may lead to metal toxicity. Of these, chronic lead poisoning is the most common. Chronic arsenic poisoning following the use of ayurvedic medication, though reported, is rare. We describe three patients who presented with features of chronic arsenic poisoning following prolonged ayurvedic medication use. The diagnosis of chronic arsenic poisoning was confirmed by high arsenic levels in the blood, urine, hair, and nails in all the three patients and in ayurvedic drug in two patients. The ayurvedic medication was discontinued and treatment with D-penicillamine started. At 6 months after treatment, blood arsenic levels returned to normal with clinical recovery in all of them. Arsenic poisoning following ayurvedic medication is much less common than lead poisoning, though mineral ayurvedic medicines may lead to it. We used D-penicillamine as chelator and all of them recovered. Whether withdrawal of medication alone or D-penicillamine also played a role in recovery is unclear and needs to be assessed.

  9. Role and mechanism of arsenic in regulating angiogenesis.

    Directory of Open Access Journals (Sweden)

    Ling-Zhi Liu

    Full Text Available Arsenic is a wide spread carcinogen associated with several kinds of cancers including skin, lung, bladder, and liver cancers. Lung is one of the major targets of arsenic exposure. Angiogenesis is the pivotal process during carcinogenesis and chronic pulmonary diseases, but the role and mechanism of arsenic in regulating angiogenesis remain to be elucidated. In this study we show that short time exposure of arsenic induces angiogenesis in both human immortalized lung epithelial cells BEAS-2B and adenocarcinoma cells A549. To study the molecular mechanism of arsenic-inducing angiogenesis, we find that arsenic induces reactive oxygen species (ROS generation, which activates AKT and ERK1/2 signaling pathways and increases the expression of hypoxia-inducible factor 1 (HIF-1 and vascular endothelial growth factor (VEGF. Inhibition of ROS production suppresses angiogenesis by decreasing AKT and ERK activation and HIF-1 expression. Inhibition of ROS, AKT and ERK1/2 signaling pathways is sufficient to attenuate arsenic-inducing angiogenesis. HIF-1 and VEGF are downstream effectors of AKT and ERK1/2 that are required for arsenic-inducing angiogenesis. These results shed light on the mechanism of arsenic in regulating angiogenesis, and are helpful to develop mechanism-based intervention to prevent arsenic-induced carcinogenesis and angiogenesis in the future.

  10. Bacteria, hypertolerant to arsenic in the rocks of an ancient gold mine, and their potential role in dissemination of arsenic pollution

    International Nuclear Information System (INIS)

    Drewniak, Lukasz; Styczek, Aleksandra; Majder-Lopatka, Malgorzata; Sklodowska, Aleksandra

    2008-01-01

    The aim of the present study was to find out if bacteria present in ancient gold mine could transform immobilized arsenic into its mobile form and increase its dissemination in the environment. Twenty-two arsenic-hypertolerant cultivable bacterial strains were isolated. No chemolithoautotrophs, which could use arsenite as an electron donor as well as arsenate as an electron acceptor, were identified. Five isolates exhibited hypertolerance to arsenic: up to 500 mM of arsenate. A correlation between the presence of siderophores and high resistance to arsenic was found. The results of this study show that detoxification processes based on arsenate reductase activity might be significant in dissemination of arsenic pollution. It was concluded that the activity of the described heterotrophic bacteria contributes to the mobilization of arsenic in the more toxic As(III) form and a new mechanism of arsenic mobilization from a scorodite was proposed. - The activity of the described heterotrophic bacteria leads to mobilization of arsenic and in this way contributes to the dissemination of arsenic pollution

  11. Arsenic uptake by Lemna minor in hydroponic system.

    Science.gov (United States)

    Goswami, Chandrima; Majumder, Arunabha; Misra, Amal Kanti; Bandyopadhyay, Kaushik

    2014-01-01

    Arsenic is hazardous and causes several ill effects on human beings. Phytoremediation is the use of aquatic plants for the removal of toxic pollutants from external media. In the present research work, the removal efficiency as well as the arsenic uptake capacity of duckweed Lemna minor has been studied. Arsenic concentration in water samples and plant biomass were determined by AAS. The relative growth factor of Lemna minor was determined. The duckweed had potential to remove as well as uptake arsenic from the aqueous medium. Maximum removal of more than 70% arsenic was achieved atinitial concentration of 0.5 mg/1 arsenic on 15th day of experimental period of 22 days. Removal percentage was found to decrease with the increase in initial concentration. From BCF value, Lemna minor was found to be a hyperaccumulator of arsenic at initial concentration of 0.5 mg/L, such that accumulation decreased with increase in initial arsenic concentration.

  12. Comparative nitrogen fixation, native arbuscular mycorrhiza formation and biomass production potentials of some grain legumes species grown in the field in the Guinea Savannah zone of Ghana

    International Nuclear Information System (INIS)

    Ahiabor, B.D.K.; Fosu, M.; Tibo, I.; Sumaila, I.

    2007-01-01

    An on-station trial was conducted in the experimental field of Savannah Agricultural Research Institute at Nyankpala in the Northern Region of Ghana to assess the nitrogen fixation, native arbuscular mycorrhizal formation and biomass production potentials of cowpea (Vigna unguiculata), devil-bean (Crotalaria retusa), Mucuna pruriens var. utilis (black and white types) and Canavalia ensiformis with maize (Dorke SR) as the reference crop using the total nitrogen difference (TND) method. Plants were fertilized with 40 kg P/ha and 30 kg K/ha at 2 weeks after planting and grown for 55 days after which they were harvested. The harvested biomass (separated into roots, stems and leaves) of each crop was oven-dried at 70 0 C for 48 h to a constant weight. Cowpea and devil-bean produced approximately 5 and 6 t/ha biomass whereas Mucuna and Canavalia yielded about 2 t/ha biomass each. Although cowpea had the least number of arbuscular mycorrhiza fungal (AMF) spores in its rhizosphere, its roots were the most heavily colonized (34%) and M. pruriens recording below 5% colonization. Apart from C. ensiformis, the test legumes derived over 50% of their total accumulated N from the atmosphere with cowpea being the most efficient (90% Ndfa). Both N and P accumulations were significantly higher in cowpea than the other legumes due to increased N concentration and dry matter accumulation, respectively. In all the legumes, there was a direct positive correlation between the extent of mycorrhiza formation, biological N fixation and total N uptake. It could, therefore, be concluded that the extensive mycorrhiza formation in cowpea and its high N 2 -fixing potential resulted in a high shoot N and P uptake leading to a comparatively better growth enhancement. Cowpea could, therefore, be the grain legume for consideration in the selection of a suitable legume pre-crop to cereals for the amelioration of the low fertility of the degraded soils of the Guinea savannah zone of Ghana, and also as

  13. Arsenic species and chemistry in groundwater of southeast Michigan

    International Nuclear Information System (INIS)

    Kim, M.-J.; Nriagu, Jerome; Haack, Sheridan

    2002-01-01

    Most of the arsenic detected was arsenite [As(III)]. - Groundwater samples, taken from 73 wells in 10 counties of southeast Michigan in 1997 had arsenic concentrations in the range of 0.5 to 278 μg/l, the average being 29 μg/l. About 12% of these wells had arsenic concentrations that exceeded the current USEPA's maximum contaminant level of 50 μg/l. Most (53-98%) of the arsenic detected was arsenite [As(III)] and other observations supported the arsenic species distribution (low redox potential and DO). In shallow groundwater ( 15 m), the concentration of arsenic is possibly controlled by reductive dissolution of arsenic-rich iron hydroxide/oxyhydroxide and dissolution of arsenic sulfide minerals

  14. Arbuscular mycorrhiza fungi mediate soil respiration response to climate change in California grasslands

    Science.gov (United States)

    Estruch, Carme; Mcfarland, Jack; Haw, Monica P.; Schulz, Marjorie S.; Pugnaire, Francisco I.; Waldrop, Mark P.

    2017-04-01

    California grasslands store ca. 100 Tg of soil organic carbon (SOC) and almost 40% of those ecosystems are prone to land use changes. The fate of these carbon pools will largely depend on how the main components of soil respiration - i.e., roots, mycorrhiza, and 'bulk soil' communities- respond to such changes. In order to determine the sensitivity to environmental drivers we set up an experiment to address the effect of plant community composition, soil age and warming on soil respiration rate during the 2014-2015 winter. We tested differences among microbial, fungal and root respiration using an exclusion technique to assess the effect of plant community (open grasslands vs oak woodland) in two field sites differing in soil properties as nutrient content, related to geologic soil age (92 and 137 kyr). We also used open top chambers (OTC) to simulate global change effects on grasslands. Our results showed that arbuscular mycorrhizal fungi were the main drivers of differences recorded between soils of different age, and that those differences were linked to nutrient availability. Bulk soil respiration was more sensitive to environmental variation than mycorrhizal or root respiration, indicating that the presence of mycorrhizae and roots can regulate the capacity of CO2 emission to the atmosphere. Soil age affected CO2 flux from grasslands but not under oak canopies, likely due to the high concentration of SOM in oak canopies which moderated any affect of soil mineralogy on nutrient availability. Overall our study shows that the ability of grasslands to mitigate CO2 emissions depends on interactions between vegetation and their rhizosphere on soil microbial communities.

  15. Arsenic contamination and arsenicosis in China

    International Nuclear Information System (INIS)

    Sun Guifan

    2004-01-01

    Arsenicosis is a serious environmental chemical disease in China mainly caused by drinking water from pump wells contaminated by high levels of arsenic. Chronic exposure of humans to high concentrations of arsenic in drinking water is associated with skin lesions, peripheral vascular disease, hypertension, blackfoot disease, and high risk of cancers. Lead by the Ministry of Health of China, we carried out a research about arsenicosis in China recently. Areas contaminated with arsenic from drinking water are determined by 10% pump well water sample method while areas from burning coal are determined by existing data. Two epidemic areas of Shanxi Province and Inner Mongolia are investigated for the distribution of pump wells containing high arsenic. Well water in all the investigated villages of Shanxi Province showed polluted by high arsenic, and the average rate of unsafe pump well water is 52%. In Inner Mongolia, the high percentage of pump wells containing elevated arsenic is found only in a few villages. The average rate of unsafe pump well water is 11%. From our research, we find that new endemic areas are continuously emerging in China. Up to now, epidemic areas of arsenicosis mainly involve eight provinces and 37 counties in China. In the affected areas, the discovery of wells and coal with high levels of arsenic is continuing sporadically, and a similar scattered distribution pattern of patients is also being observed

  16. Groundwater arsenic contamination throughout China.

    Science.gov (United States)

    Rodríguez-Lado, Luis; Sun, Guifan; Berg, Michael; Zhang, Qiang; Xue, Hanbin; Zheng, Quanmei; Johnson, C Annette

    2013-08-23

    Arsenic-contaminated groundwater used for drinking in China is a health threat that was first recognized in the 1960s. However, because of the sheer size of the country, millions of groundwater wells remain to be tested in order to determine the magnitude of the problem. We developed a statistical risk model that classifies safe and unsafe areas with respect to geogenic arsenic contamination in China, using the threshold of 10 micrograms per liter, the World Health Organization guideline and current Chinese standard for drinking water. We estimate that 19.6 million people are at risk of being affected by the consumption of arsenic-contaminated groundwater. Although the results must be confirmed with additional field measurements, our risk model identifies numerous arsenic-affected areas and highlights the potential magnitude of this health threat in China.

  17. Trace speciation analysis of arsenic in beverages

    OpenAIRE

    Fajgarová, Aneta

    2016-01-01

    The aim of this bachelor thesis was to determine the toxicologically important arsenic species in beverages (beer, wine and apple juice) with minimal sample preparation. Determination of arsenic species was performed by selective hydride generation of arsenic hydrides with cryogenic collection under liquid nitrogen and detection by atomic absorption spectrometry. In all the samples only inorganic arsenic was found, methyl substituted species were below the limit of detection. The method is su...

  18. ARSENIC CONTAMINATION IN GROUNDWATER: A STATISTICAL MODELING

    OpenAIRE

    Palas Roy; Naba Kumar Mondal; Biswajit Das; Kousik Das

    2013-01-01

    High arsenic in natural groundwater in most of the tubewells of the Purbasthali- Block II area of Burdwan district (W.B, India) has recently been focused as a serious environmental concern. This paper is intending to illustrate the statistical modeling of the arsenic contaminated groundwater to identify the interrelation of that arsenic contain with other participating groundwater parameters so that the arsenic contamination level can easily be predicted by analyzing only such parameters. Mul...

  19. Strategies for the engineered phytoremediation of toxic element pollution: mercury and arsenic.

    Science.gov (United States)

    Meagher, Richard B; Heaton, Andrew C P

    2005-12-01

    Plants have many natural properties that make them ideally suited to clean up polluted soil, water, and air, in a process called phytoremediation. We are in the early stages of testing genetic engineering-based phytoremediation strategies for elemental pollutants like mercury and arsenic using the model plant Arabidopsis. The long-term goal is to develop and test vigorous, field-adapted plant species that can prevent elemental pollutants from entering the food-chain by extracting them to aboveground tissues, where they can be managed. To achieve this goal for arsenic and mercury, and pave the way for the remediation of other challenging elemental pollutants like lead or radionucleides, research and development on native hyperaccumulators and engineered model plants needs to proceed in at least eight focus areas: (1) Plant tolerance to toxic elementals is essential if plant roots are to penetrate and extract pollutants efficiently from heterogeneous contaminated soils. Only the roots of mercury- and arsenic-tolerant plants efficiently contact substrates heavily contaminated with these elements. (2) Plants alter their rhizosphere by secreting various enzymes and small molecules, and by adjusting pH in order to enhance extraction of both essential nutrients and toxic elements. Acidification favors greater mobility and uptake of mercury and arsenic. (3) Short distance transport systems for nutrients in roots and root hairs requires numerous endogenous transporters. It is likely that root plasma membrane transporters for iron, copper, zinc, and phosphate take up ionic mercuric ions and arsenate. (4) The electrochemical state and chemical speciation of elemental pollutants can enhance their mobility from roots up to shoots. Initial data suggest that elemental and ionic mercury and the oxyanion arsenate will be the most mobile species of these two toxic elements. (5) The long-distance transport of nutrients requires efficient xylem loading in roots, movement through the

  20. Arsenic poisoning of cattle and other domestic animals

    Energy Technology Data Exchange (ETDEWEB)

    Moxham, J W; Coup, M R

    1968-01-01

    One hundred and sixty-one incidents of arsenic poisoning in domestic animals were recorded at Ruakura Veterinary Diagnostic Station from 1955 to 1967. Cattle was the animal species most subject to arsenic poisoning. Clincal signs, post-mortem findings and sources of arsenic are given. Arsenic poisoning was more prevalent in younger cattle and during the warmer months of the year. With cattle most incidents were associated with carelessly discarded arsenical compounds, although most deaths occurred when these compounds were deliberately used. In other species, losses were generally caused by the deliberate use of arsenical preparations for dipping, drenching and weed spraying. 10 references, 2 tables.

  1. Arsenic in the environment: enrichments in the Slovenian soils

    Directory of Open Access Journals (Sweden)

    Mateja Gosar

    2005-12-01

    Full Text Available Arsenic, a toxic element with metalloid properties, is found in detectable concentrations in environmental samples. In nature it is enriched in metal (sulphide ore deposits, mainly as arsenides of Cu, Ni and Fe. Arsenic compounds are used mainly in agricultureand forestry as pesticides and herbicides. The ecosystem can be contaminated with arsenic via both natural and anthropogenic sources. Uses of arsenic contaminated water present so far the greatest health hazard. Occurrences of mining related arsenic problems havealso been recorded in many parts of the world.The impact of mining and metallurgic industry with regard to arsenic contents in soils in some potentially contaminated areas in Slovenia is discussed. Enriched contents of arsenic were found in Mežica. Arsenic correlates very well with lead, zinc and other heavymetals which are enriched as a result of long lasting lead production in the area. Also in Celje and Jesenice arsenic has the same distribution pattern as other anthropogenically introduced pollutants. In Idrija there are some slightly arsenic enriched areas, but there is no correlation with mercury, so the origin of arsenic in not clear yet.

  2. Arsenic (Environmental Health Student Portal)

    Science.gov (United States)

    ... Water Waterborne Diseases & Illnesses Water Cycle Water Treatment Videos Games Experiments For Teachers Home Chemicals Arsenic Print this ... human activities, such as mining, farming, and other industries. This can be dangerous, because arsenic is poisonous ...

  3. Napoleon Bonaparte's exposure to arsenic during 1816.

    Science.gov (United States)

    Leslie, A C; Smith, H

    1978-12-11

    Analysis of hair from Napoleon showed that he was exposed to considerable amounts of arsenic during 1816. The distribution pattern of the arsenic in the hair is similar to that found after the daily ingestion of excessive amounts of arsenic.

  4. Speciation of arsenic in rice and estimation of daily intake of different arsenic species by Brazilians through rice consumption.

    Science.gov (United States)

    Batista, Bruno L; Souza, Juliana M O; De Souza, Samuel S; Barbosa, Fernando

    2011-07-15

    Rice is an important source of essential elements. However, rice may also contain toxic elements such as arsenic. Therefore, in the present study, the concentration of total arsenic and five main chemical species of arsenic (As(3+), As(5+), DMA, MMA and AsB) were evaluated in 44 different rice samples (white, parboiled white, brown, parboiled brown, parboiled organic and organic white) from different Brazilian regions using high-performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The mean level of total arsenic was 222.8 ng g(-1) and the daily intake of inorganic arsenic (the most toxic form) from rice consumption was estimated as 10% of the Provisional Tolerable Daily Intake (PTDI) with a daily ingestion of 88 g of rice. Inorganic arsenic (As(3+), As(5+)) and dimethylarsinic acid (DMA) are the predominant forms in all samples. The percentages of species were 38.7; 39.7; 3.7 and 17.8% for DMA, As(3+), MMA and As(5+), respectively. Moreover, rice samples harvested in the state of Rio Grande do Sul presented more fractions of inorganic arsenic than rice in Minas Gerais or Goiás, which could lead to different risks of arsenic exposure. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Enzyme-assisted extraction and liquid chromatography mass spectrometry for the determination of arsenic species in chicken meat.

    Science.gov (United States)

    Liu, Qingqing; Peng, Hanyong; Lu, Xiufen; Le, X Chris

    2015-08-12

    Chicken is the most consumed meat in North America. Concentrations of arsenic in chicken range from μg kg(-1) to mg kg(-1). However, little is known about the speciation of arsenic in chicken meat. The objective of this research was to develop a method enabling determination of arsenic species in chicken breast muscle. We report here enzyme-enhanced extraction of arsenic species from chicken meat, separation using anion exchange chromatography (HPLC), and simultaneous detection with both inductively coupled plasma mass spectrometry (ICPMS) and electrospray ionization tandem mass spectrometry (ESIMS). We compared the extraction of arsenic species using several proteolytic enzymes: bromelain, papain, pepsin, proteinase K, and trypsin. With the use of papain-assisted extraction, 10 arsenic species were extracted and detected, as compared to 8 detectable arsenic species in the water/methanol extract. The overall extraction efficiency was also improved using a combination of ultrasonication and papain digestion, as compared to the conventional water/methanol extraction. Detection limits were in the range of 1.0-1.8 μg arsenic per kg chicken breast meat (dry weight) for seven arsenic species: arsenobetaine (AsB), inorganic arsenite (As(III)), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), inorganic arsenate (As(V)), 3-nitro-4-hydroxyphenylarsonic acid (Roxarsone), and N-acetyl-4-hydroxy-m-arsanilic acid (NAHAA). Analysis of breast meat samples from six chickens receiving feed containing Roxarsone showed the presence of (mean±standard deviation μg kg(-1)) AsB (107±4), As(III) (113±7), As(V) (7±2), MMA (51±5), DMA (64±6), Roxarsone (18±1), and four unidentified arsenic species (approximate concentration 1-10 μg kg(-1)). Copyright © 2015 Elsevier B.V. All rights reserved.

  6. An investigation of the health effects caused by exposure to arsenic from drinking water and coal combustion: arsenic exposure and metabolism.

    Science.gov (United States)

    Wei, Binggan; Yu, Jiangping; Kong, Chang; Li, Hairong; Yang, Linsheng; Guo, Zhiwei; Cui, Na; Xia, Yajuan; Wu, Kegong

    2017-11-01

    Few studies have been conducted to compare arsenic exposure, metabolism, and methylation in populations exposed to arsenic in drinking water and from coal combustion. Therefore, arsenic concentrations in the environment and arsenic speciation in the urine of subjects exposed to arsenic as a consequence of coal combustion in a rural area in Shaanxi province (CCA) and in drinking water in a rural area in Inner Mongolia (DWA) were investigated. The mean arsenic concentrations in drinking water, indoor air, and soil in CCA were 4.52 μg/L, 0.03 mg/m 3 , and 14.93 mg/kg, respectively. The mean arsenic concentrations in drinking water and soil in DWA were 144.71 μg/L and 10.19 mg/kg, respectively, while the level in indoor air was lower than the limit of detection. The total daily intakes of arsenic in DWA and CCA were 4.47 and 3.13 μg/day·kg, respectively. The mean urinary concentrations of inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsenic acid (DMA), and total arsenic (TAs) for subjects with skin lesions in DWA were 50.41, 47.01, 202.66, and 300.08 μg/L. The concentrations for subjects without skin lesions were 49.76, 44.20, 195.60, and 289.56 μg/L, respectively. The %iAs, %MMA, and %DMA in the TAs in the urine of subjects from CCA were 12.24, 14.73, and 73.03%, while the corresponding values from DWA were 17.54, 15.57, and 66.89%, respectively. The subjects in DWA typically had a higher %iAs and %MMA, and a lower %DMA, and primary and secondary methylation index (PMI and SMI) than the subjects in CCA. It was concluded that the arsenic methylation efficiency of subjects in DWA and CCA was significantly influenced by chronic exposure to high levels of arsenic in the environment. The lower PMI and SMI values in DWA revealed lower arsenic methylation capacity due to ingestion of arsenic in drinking water. However, it remained unclear if the differences in arsenic metabolism between the two groups were due to differences in exposure levels

  7. Combined Administration of Taurine and Monoisoamyl Dmsa Protects Arsenic Induced Oxidative Injury in Rats

    Directory of Open Access Journals (Sweden)

    Swaran J. S. Flora

    2008-01-01

    Full Text Available Arsenic is a naturally occurring element that is ubiquitously present in the environment. High concentration of naturally occurring arsenic in drinking water is a major health problem in different parts of the world. Despite arsenic being a health hazard and a well documented carcinogen, no safe, effective and specific preventive or therapeutic measures are available. Among various recent strategies adopted, administration of an antioxidant has been reported to be the most effective. The present study was designed to evaluate the therapeutic efficacy of monoisoamyl dimercaptosuccinic acid (MiADMSA, administered either individually or in combination with taurine post chronic arsenic exposure in rats. Arsenic exposed male rats (25 ppm, sodium arsenite in drinking water for 24 weeks were treated with taurine (100 mg/kg, i.p., once daily, monoisoamyl dimercaptosuccinic acid (MiADMSA (50 mg/kg, oral, once daily either individually or in combination for 5 consecutive days. Biochemical variables indicative of oxidative stress along-with arsenic concentration in blood, liver and kidney were measured. Arsenic exposure significantly reduced blood δ-aminolevulinic acid dehydratase (ALAD activity, a key enzyme involved in the heme biosynthesis and enhanced zinc protoporphyrin (ZPP level. Clinical hematological variables like white blood cells (WBC, mean cell hemoglobin (MCH, and mean cell hemoglobin concentration (MCHC showed significant decrease with a significant elevation in platelet (PLT count. These changes were accompanied by significant decrease in superoxide dismutase (SOD activity and increased catalase activity. Arsenic exposure caused a significant decrease in hepatic and renal glutathione (GSH level and an increase in oxidized glutathione (GSSG. These biochemical changes were correlated with an increased uptake of arsenic in blood, liver and kidney. Administration of taurine significantly reduced hepatic oxidative stress however co

  8. Arsenic concentrations, related environmental factors, and the predicted probability of elevated arsenic in groundwater in Pennsylvania

    Science.gov (United States)

    Gross, Eliza L.; Low, Dennis J.

    2013-01-01

    Analytical results for arsenic in water samples from 5,023 wells obtained during 1969–2007 across Pennsylvania were compiled and related to other associated groundwater-quality and environmental factors and used to predict the probability of elevated arsenic concentrations, defined as greater than or equal to 4.0 micrograms per liter (µg/L), in groundwater. Arsenic concentrations of 4.0 µg/L or greater (elevated concentrations) were detected in 18 percent of samples across Pennsylvania; 8 percent of samples had concentrations that equaled or exceeded the U.S. Environmental Protection Agency’s drinking-water maximum contaminant level of 10.0 µg/L. The highest arsenic concentration was 490.0 µg/L.

  9. Phytoremediation of arsenic contaminated soil by Pteris vittata L. II. Effect on arsenic uptake and rice yield.

    Science.gov (United States)

    Mandal, Asit; Purakayastha, T J; Patra, A K; Sanyal, S K

    2012-07-01

    A greenhouse experiment evaluated the effect of phytoextraction of arsenic from a contaminated soil by Chinese Brake Fern (Pteris vittata L.) and its subsequent effects on growth and uptake of arsenic by rice (Oryza sativa L.) crop. Pteris vittata was grown for one or two growing cycles of four months each with two phosphate sources, using single super phosphate (SSP) and di-ammonium phosphate (DAP). Rice was grown on phytoextracted soils followed by measurements of biomass yield (grain, straw, and root), arsenic concentration and, uptake by individual plant parts. The biomass yield (grain, straw and rice) of rice was highest in soil phytoextracted with Pteris vittata grown for two cycles and fertilized with diammonium phosphate (DAP). Total arsenic uptake in contaminated soil ranged from 8.2 to 16.9 mg pot(-1) in first growing cycle and 5.5 to 12.0 mg pot(-1) in second growing cycle of Pteris vittata. There was thus a mean reduction of 52% in arsenic content of rice grain after two growing cycle of Pteris vittata and 29% after the one growing cycle. The phytoextraction of arsenic contaminated soil by Pteris vittata was beneficial for growing rice resulted in decreased arsenic content in rice grain of <1 ppm. There was a mean improvement in rice grain yield 14% after two growing cycle and 8% after the one growing cycle of brake fern.

  10. Arsenic in contaminated soil and river sediment

    International Nuclear Information System (INIS)

    Bombach, G.; Pierra, A.; Klemm, W.

    1994-01-01

    Different areas in the Erzgebirge mountains are contaminated by high arsenic concentration which is caused by the occurrence of ore and industrial sources. The study showed clearly a high concentration of arsenic in the surface and under soil (A and B horizons) in the Freiberg district. The distribution of the arsenic concentration in the area, the content of water soluble arsenic, the several oxidation states (As 3+ , As 5+ ) and the bonding types have been analyzed. (orig.)

  11. Brimstone chemistry under laser light assists mass spectrometric detection and imaging the distribution of arsenic in minerals.

    Science.gov (United States)

    Lal, Swapnil; Zheng, Zhaoyu; Pavlov, Julius; Attygalle, Athula B

    2018-05-23

    Singly charged As2n+1 ion clusters (n = 2-11) were generated from elemental arsenic by negative-ion laser-ablation mass spectrometry. The overall abundance of the gaseous As ions generated upon laser irradiation was enhanced nearly a hundred times when As-bearing samples were admixed with sulfur. However, sulfur does not act purely as an inert matrix: irradiating arsenic-sulfur mixtures revealed a novel pathway to generate and detect a series of [AsSn]- clusters (n = 2-6). Intriguingly, the spectra recorded from As2O3, NaAsO2, Na3AsO4, cacodylic acid and 3-amino-4-hydroxyphenylarsonic acid together with sulfur as the matrix were remarkably similar to that acquired from an elemental arsenic and sulfur mixture. This result indicated that arsenic sulfide cluster-ions are generated directly from arsenic compounds by a hitherto unknown pathway. The mechanism of elemental sulfur extracting chemically bound arsenic from compounds and forming [AsSn]- clusters is enigmatic; however, this discovery has a practical value as a general detection method for arsenic compounds. For example, the method was employed for the detection of As in its minerals, and for the imaging of arsenic distribution in minerals such as domeykite. LDI-MS data recorded from a latent image imprinted on a piece of paper from a flat mineral surface, and wetting the paper with a solution of sulfur, enabled the localization of arsenic in the mineral. The distribution of As was visualized as false-color images by extracting from acquired data the relative intensities of m/z 139 (AsS2-) and m/z 171 (AsS3-) ions.

  12. Origin, mobility, and temporal evolution of arsenic from a low-contamination catchment in Alpine crystalline rocks

    Energy Technology Data Exchange (ETDEWEB)

    Pili, Eric, E-mail: Eric.Pili@cea.fr [CEA, DAM, DIF, F-91297 Arpajon (France); Institut de Physique du Globe de Paris-Sorbonne Paris Cité, CNRS, Université Paris Diderot, 1 rue Jussieu, F-75238 Paris cedex 05 (France); Tisserand, Delphine, E-mail: Delphine.Tisserand@obs.ujf-grenoble.fr [Institut des Sciences de la Terre (ISTerre) Université Joseph Fourier and CNRS, BP 53, 38041 Grenoble cedex 9 (France); Bureau, Sarah, E-mail: Sarah.Bureau@obs.ujf-grenoble.fr [Institut des Sciences de la Terre (ISTerre) Université Joseph Fourier and CNRS, BP 53, 38041 Grenoble cedex 9 (France)

    2013-11-15

    Highlights: ► δ{sup 34}S{sub SO4} vs. [As] and δ{sup 18}O{sub SO4} vs. As{sup V}/As{sup III} correlations provide new tools even for low [As]. ► Long-term and high-resolution monitoring shows droughts enhance pyrite dissolution. ► Major effect of 2003 European heatwave on pyrite dissolution and [As] increase. -- Abstract: The reduction to 10 μg/l of the limit for arsenic in drinking water led many resource managers to deal with expensive treatments. In the very common case of arsenic levels close to the recommended maximum concentration, knowing the origin and temporal evolution of As has become of great importance. Here we present a case study from an alpine basin. Arsenic speciation, isotopic compositions of pyrite, sulfate and water, and concentrations of major and trace elements demonstrate a geogenic source for arsenic linked to the dissolution of pyrite. We provide new tools to further study As at low concentrations where many processes may be masked. The observed negative correlation between δ{sup 34}S{sub SO4} and [As] is interpreted as a Rayleigh-type sulfur-isotope fractionation during increasing pyrite dissolution. The observed positive correlation between δ{sup 18}O{sub SO4} and As{sup V}/As{sup III} could help to retrieve initial redox conditions. A 3-year long monitoring at high-resolution demonstrated that drought conditions enhance pyrite dissolution whose degradation products are scavenged by recharge water. An increase in As in groundwater may result from droughts due to enhanced oxygen entry in the unsaturated zone. The 2003 European heatwave had a major effect.

  13. A comparison of the development and metabolic activity of mycorrhizas formed by arbuscular mycorrhizal fungi from different genera on two tropical forage legumes

    NARCIS (Netherlands)

    Boddington, C.L.; Dodd, J.C.

    1998-01-01

    Two glasshouse experiments were done to assess the development and metabolic activity of mycorrhizas formed by isolates of arbuscular mycorrhizal fungi (AMF) from three different genera, Acaulospora, Gigaspora and Glomus on either Pueraria phaseoloides L. or Desmodium ovalifolium L. plants. The

  14. Dietary arsenic consumption and urine arsenic in an endemic population: response to improvement of drinking water quality in a 2-year consecutive study.

    Science.gov (United States)

    Biswas, Anirban; Deb, Debasree; Ghose, Aloke; Du Laing, Gijs; De Neve, Jan; Santra, Subhas Chandra; Guha Mazumder, Debendra Nath

    2014-01-01

    We assessed the association between arsenic intake through water and diet, and arsenic levels in first morning-void urine under variable conditions of water contamination. This was done in a 2-year consecutive study in an endemic population. Exposure of arsenic through water and diet was assessed for participants using arsenic-contaminated water (≥50 μg L(-1)) in a first year (group I) and for participants using water lower in arsenic (water in groups I and II males was 7.44 and 0.85 μg kg body wt.(-1) day(-1) (p water were reduced to below 50 μg L(-1) (Indian permissible limit), total arsenic intake and arsenic intake through the water significantly decreased, but arsenic uptake through the diet was found to be not significantly affected. Moreover, it was found that drinking water mainly contributed to variations in urine arsenic concentrations. However, differences between male and female participants also indicate that not only arsenic uptake, but also many physiological factors affect arsenic behavior in the body and its excretion. As total median arsenic exposure still often exceeded 3.0 μg kg body wt.(-1) day(-1) (the permissible lower limit established by the Joint Expert Committee on Food Additives) after installation of the drinking water filters, it can be concluded that supplying the filtered water only may not be sufficient to minimize arsenic availability for an already endemic population.

  15. Arsenic and selenium in microbial metabolism

    Science.gov (United States)

    Stolz, John F.; Basu, Partha; Santini, Joanne M.; Oremland, Ronald S.

    2006-01-01

    Arsenic and selenium are readily metabolized by prokaryotes, participating in a full range of metabolic functions including assimilation, methylation, detoxification, and anaerobic respiration. Arsenic speciation and mobility is affected by microbes through oxidation/reduction reactions as part of resistance and respiratory processes. A robust arsenic cycle has been demonstrated in diverse environments. Respiratory arsenate reductases, arsenic methyltransferases, and new components in arsenic resistance have been recently described. The requirement for selenium stems primarily from its incorporation into selenocysteine and its function in selenoenzymes. Selenium oxyanions can serve as an electron acceptor in anaerobic respiration, forming distinct nanoparticles of elemental selenium that may be enriched in (76)Se. The biogenesis of selenoproteins has been elucidated, and selenium methyltransferases and a respiratory selenate reductase have also been described. This review highlights recent advances in ecology, biochemistry, and molecular biology and provides a prelude to the impact of genomics studies.

  16. Enhanced Column Filtration for Arsenic Removal from Water: Polymer-Templated Iron Oxide Nanoparticles Immobilized on Sand via Layer-by-Layer Deposition

    Science.gov (United States)

    Cheng, Calvin Chia-Hung

    Arsenic is ubiquitous in water sources around the world and is highly toxic. While precipitation and membrane filtration techniques are successfully implemented in developed cities, they are unsuitable for rural and low-resource settings lacking centralized facilities. This thesis presents the use of ultra-small iron oxide (Fe2O3) nanoparticles functionalized on sand granules for use as a house-hold scale adsorption filter. Water-stable alpha-Fe2O3 (hematite) nanoparticles (arsenic adsorption, with 147 +/- 2 mg As(III) per g Fe2O3 and 91 +/- 10 mg As(V) per g Fe2O3. The platform was also used to synthesize iron-based composites, including magnetite (Fe 3O4) and Fe-Cu oxide nanoparticles. For use as a column filter, Fe2O3-PAA nanoparticles were functionalized on sand granules using a layer-by-layer deposition method, with the nanoparticles embedded in the negative layer. The removal of As(III) by the Fe2O 3-PAA functionalized column was described by reversible 1st order kinetics where the forward and reverse rate constants were 0.31 hr -1 and 0.097 hr-1, respectively. Implemented as a passive water filter with 30 x 30 x 50 cm3 dimensions, the filter has an expected lifetime in the order of many years. By controlling the flow rate of the column depending on contamination levels, the filter effectively removes arsenic down to the safety limit of 0.01 mg/L. In a parallel project, the layer-by-layer deposition of Poly(diallydimethyl ammonium chloride) (PDDA) and poly(sodium 5-styrenesulfonate) (PSS) was exploited for a highly practical synthesis of discrete gradient surfaces. By independently controlling the concentration of NaCl in PDDA and PSS deposition solutions, a 2-dimensional matrix of surfaces was created in 96-well microtiter plates. Distinct non-monotonic dye adsorption patterns on the gradient surfaces was observed. Practical knowledge from this project was also used to enhance the nanoparticle surface functionalization described above. In all, a practical

  17. Alleviating salt stress in tomato inoculated with mycorrhizae: Photosynthetic performance and enzymatic antioxidants

    Directory of Open Access Journals (Sweden)

    Mohsen K.H. Ebrahim

    2017-11-01

    Full Text Available Tomato cultivars (Sultana-7 & Super Strain-B were germinated with various concentrations (0–200 mM of NaCl. Seed germination in the Super Strain-B was promoted by 25 mM NaCl. However, the germination of both cultivars was progressively inhibited by 50 and 100 mM NaCl and obstructed at 200 mM NaCl, and this response was more pronounced for Sultana-7. Therefore, Super Strain-B was selected for further investigation, such as growth under NaCl stress (50 & 100 mM and inoculation with vesicular-arbuscular mycorrhizal fungus (Glomus fasciculatum, VAMF. The leaves of Super Strain-B showed reduced mineral (N, P, K, Mg uptake and K/Na ratio as well as increased Na uptake and N/P ratio in response to salinity. Moreover, salinity decreased the chlorophyll (Chl contents coupled with an increase in Chl a/b, Hill-reaction activity, and quenched Chl a fluorescence emission. These changes reflect a disturbance in the structure, composition and function of the photosynthetic apparatus as well as the activity of photosystem 2. The superoxide dismutase and peroxidase activities of leaves were enhanced by salinity, whereas the catalase activity was decreased. Leaf polysaccharides and proteins as well as shoot biomass also decreased as a result of salinity, but the total soluble sugars and root to shoot ratio improved.VAMF enhanced both the photosynthesis and productivity of plants; thus, VAMF may alleviate the adverse effects of salinity in plants by increasing their salt tolerance. Although mycorrhizal infection showed a negative correlation with salinity, it remained relatively high (21 & 25% at 100 mM NaCl. Keywords: Mycorrhizae, tomato, salinity, minerals, photosynthetic performance and antioxidant enzymes

  18. Heavy metal, total arsenic, and inorganic arsenic contents of algae food products.

    Science.gov (United States)

    Almela, C; Algora, S; Benito, V; Clemente, M J; Devesa, V; Súñer, M A; Vélez, D; Montoro, R

    2002-02-13

    The total arsenic, inorganic arsenic, lead, cadmium, and mercury contents of 18 algae food products currently on sale in Spain were determined. The suitability of the analytical methodologies for this type of matrix was confirmed by evaluating their analytical characteristics. The concentration ranges found for each contaminant, expressed in milligrams per kilogram of dry weight, were as follows: total arsenic, 2.3-141; inorganic arsenic, 0.15-88; lead, mercury, 0.004-0.04. There is currently no legislation in Spain regarding contaminants in algae food products, but some of the samples analyzed revealed Cd and inorganic As levels higher than those permitted by legislation in other countries. Given the high concentrations of inorganic As found in Hizikia fusiforme, a daily consumption of 1.7 g of the product would reach the Provisional Tolerable Weekly Intake recommended by the WHO for an average body weight of 68 kg. A more comprehensive study of the contents and toxicological implications of the inorganic As present in the algae food products currently sold in Spain may be necessary, which might then be the basis for the introduction of specific sales restrictions.

  19. Groundwater arsenic contamination in Bangladesh-21 Years of research.

    Science.gov (United States)

    Chakraborti, Dipankar; Rahman, Mohammad Mahmudur; Mukherjee, Amitava; Alauddin, Mohammad; Hassan, Manzurul; Dutta, Rathindra Nath; Pati, Shymapada; Mukherjee, Subhash Chandra; Roy, Shibtosh; Quamruzzman, Quazi; Rahman, Mahmuder; Morshed, Salim; Islam, Tanzima; Sorif, Shaharir; Selim, Md; Islam, Md Razaul; Hossain, Md Monower

    2015-01-01

    Department of Public Health Engineering (DPHE), Bangladesh first identified their groundwater arsenic contamination in 1993. But before the international arsenic conference in Dhaka in February 1998, the problem was not widely accepted. Even in the international arsenic conference in West-Bengal, India in February, 1995, representatives of international agencies in Bangladesh and Bangladesh government attended the conference but they denied the groundwater arsenic contamination in Bangladesh. School of Environmental Studies (SOES), Jadavpur University, Kolkata, India first identified arsenic patient in Bangladesh in 1992 and informed WHO, UNICEF of Bangladesh and Govt. of Bangladesh from April 1994 to August 1995. British Geological Survey (BGS) dug hand tube-wells in Bangladesh in 1980s and early 1990s but they did not test the water for arsenic. Again BGS came back to Bangladesh in 1992 to assess the quality of the water of the tube-wells they installed but they still did not test for arsenic when groundwater arsenic contamination and its health effects in West Bengal in Bengal delta was already published in WHO Bulletin in 1988. From December 1996, SOES in collaboration with Dhaka Community Hospital (DCH), Bangladesh started analyzing hand tube-wells for arsenic from all 64 districts in four geomorphologic regions of Bangladesh. So far over 54,000 tube-well water samples had been analyzed by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS). From SOES water analysis data at present we could assess status of arsenic groundwater contamination in four geo-morphological regions of Bangladesh and location of possible arsenic safe groundwater. SOES and DCH also made some preliminary work with their medical team to identify patients suffering from arsenic related diseases. SOES further analyzed few thousands biological samples (hair, nail, urine and skin scales) and foodstuffs for arsenic to know arsenic body burden and people sub

  20. Groundwater arsenic in Chimaltenango, Guatemala.

    Science.gov (United States)

    Lotter, Jason T; Lacey, Steven E; Lopez, Ramon; Socoy Set, Genaro; Khodadoust, Amid P; Erdal, Serap

    2014-09-01

    In the Municipality of Chimaltenango, Guatemala, we sampled groundwater for total inorganic arsenic. In total, 42 samples were collected from 27 (43.5%) of the 62 wells in the municipality, with sites chosen to achieve spatial representation throughout the municipality. Samples were collected from household faucets used for drinking water, and sent to the USA for analysis. The only site found to have a concentration above the 10 μg/L World Health Organization provisional guideline for arsenic in drinking water was Cerro Alto, where the average concentration was 47.5 μg/L. A health risk assessment based on the arsenic levels found in Cerro Alto showed an increase in noncarcinogenic and carcinogenic risks for residents as a result of consuming groundwater as their primary drinking water source. Using data from the US Geological Survey and our global positioning system data of the sample locations, we found Cerro Alto to be the only site sampled within the tertiary volcanic rock layer, a known source of naturally occurring arsenic. Recommendations were made to reduce the levels of arsenic found in the community's drinking water so that the health risks can be managed.

  1. Low selenium status affects arsenic metabolites in an arsenic exposed population with skin lesions.

    Science.gov (United States)

    Huang, Zhi; Pei, Qiuling; Sun, Guifan; Zhang, Sichum; Liang, Jiang; Gao, Yi; Zhang, Xinrong

    2008-01-01

    The antagonistic effects between selenium (Se) and arsenic (As) suggest that low selenium status plays important roles in arsenism development. However, no study has been reported for humans suffering from chronic arsenic exposure with low selenium status. Sixty-three subjects were divided into 2 experimental groups by skin lesions (including hyperkeratosis, depigmentation, and hyperpigmentation). Total urine and serum concentrations of arsenic and selenium were determined by ICP-MS with collision/reaction cell. Arsenic species were analysed by ICP-MS coupled with HPLC. The mean concentration of As in the drinking waters was 41.5 microg/l. The selenium dietary intake for the studied population was 31.7 microg Se/d, and which for the cases and controls were 25.9 and 36.3 microg Se/d, respectively. Compared with the controls, the skin lesions cases had lower selenium concentrations in serum and urine (41.4 vs 49.6 microg/l and 71.0 vs 78.8 microg/l, respectively), higher inorganic arsenic (iAs) in serum (5.2 vs 3.4 microg/l, PiAs in serum and urine (20.2) vs 16.9% and 18.3 vs 14.5%, respectively, PiAs and its inhibition to be biotransformed to DMA occurred in human due to chronic exposure of low selenium status.

  2. Vescicular-arbuscular mycorrhiza and Azospirillum brasilense rhizocoenosis in pearlmillet in a semi-arid soil

    International Nuclear Information System (INIS)

    Tilak, K.V.B.R.; Sachdev, M.S.; Sachdev, Pamila

    2007-01-01

    A field experiment was conducted in an alluvial sandy loam soil using Pearlmillet as the test crop to study the effect of Vescicular-Arbuscular Mycorrhiza (VAM) and Azospirillum with phosphorus on yield and other parameters. Dual inoculation gave a significant increase in Azospirillum and VAM infection in root over the control plants, and resulted in significant increase in grain yield. Combined inoculation alongwith N and P application showed maximum P uptake. Nitrogen fixation increased with plant growth with dually inoculated N and P treatment, The effect was more pronounced in the presence of phosphrous indicating that P is required for nitrogen fixation. (author)

  3. Arsenic in groundwater of the Kolkata Municipal Corporation (KMC), India: Critical review and modes of mitigation.

    Science.gov (United States)

    Chakraborti, Dipankar; Das, Bhaskar; Rahman, Mohammad Mahmudur; Nayak, Bishwajit; Pal, Arup; Sengupta, Mrinal K; Ahamed, Sad; Hossain, Md Amir; Chowdhury, Uttam K; Biswas, Bhajan Kumar; Saha, Khitish Chandra; Dutta, R N

    2017-08-01

    This study represents the first comprehensive report of groundwater arsenic contamination status in the Kolkata Municipal Corporation (KMC). During the past 23 years, 4210 groundwater samples were analysed from all 141 wards in the KMC: 14.2% and 5.2% samples had arsenic >10 μg/l and >50 μg/l, respectively, representing 77 and 37 wards. The study shows that the number of arsenic contaminated samples (and wards) in the southern part of the KMC exceeds that of other parts of the city. The daily intake of arsenic from drinking water was estimated as 0.95 μg per kg bw and the cancer risk was estimated as 1425/10 6 . Analyses of biological samples (hair, nail and urine) showed elevated concentrations of arsenic indicating the presence of subclinical arsenic poisoning, predicting an enhanced lifetime cancer risk for the population in southern part of the KMC. In the KMC, groundwater is not a sustainable source of freshwater due to arsenic, high iron, hardness and total dissolved solids. Its continued use is impelled by the lack of an adequate infrastructure to treat and supply surface water and in some wards the unaccounted for water (UFW) is even >45% incurred during distribution. The rare imposition of a water tax makes the water supply systems unsustainable and fosters indifference to water conservation. To mitigate the arsenic problem, continuous groundwater monitoring for pollutants, a treated surface water supply with strict policy implications, rainwater harvesting in the urban areas and introduction of water taxes seem to be long-term visible solutions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Arsenic compounds in a marine food chain

    Energy Technology Data Exchange (ETDEWEB)

    Goessler, W.; Irgolic, K.J.; Kuehnelt, D.; Schlagenhaufen, C. [Institute for Analytical Chemistry, Karl-Franzens-Universitaet Graz, Universitaetsplatz 1, A-8010 Graz (Austria); Maher, W. [CRC for Freshwater Ecology, University of Canberra, PO Box 1, Belconnen ACT. 2616 (Australia); Kaise, T. [Laboratory of Environmental Chemistry, School of Life Science, University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachijoji, Tokyo 192-03 (Japan)

    1997-10-01

    A three-organism food chain within a rock pool at Rosedale, NSW, Australia, was investigated with respect to arsenic compounds by high performance liquid chromatography - hydraulic high pressure nebulization - inductively coupled plasma mass spectrometry (HPLC-HHPN-ICP-MS). Total arsenic concentration was determined in the seaweed Hormosira banksii (27.2 {mu}g/g dry mass), in the gastropod Austrocochlea constricta (74.4 {mu}g/g dry mass), which consumes the seaweed, and in the gastropod Morula marginalba (233 {mu}g/g dry mass), which eats Austrocochlea constricta. The major arsenic compounds in the seaweed were (2`R)-dimethyl[1-O-(2`,3`-dihydroxypropyl)-5-deoxy-{beta}-d-ribofuranos-5-yl]arsine oxide and an unidentified compound. The herbivorous gastropod Austrocochlea constricta transformed most of the arsenic taken up with the seaweed to arsenobetaine. Traces of arsenite, arsenate, dimethylarsinic acid, arsenocholine, the tetramethylarsonium cation, and several unknown arsenic compounds were detected. Arsenobetaine accounted for 95% of the arsenic in the carnivorous gastropod Morula marginalba. In Morula marginalba the concentration of arsenocholine was higher, and the concentrations of the minor arsenic compounds lower than in the herbivorous gastropod Austrocochlea constricta. (orig.) With 4 figs., 1 tab., 13 refs.

  5. Arsenic-induced nutrient uptake in As-hyperaccumulator Pteris vittata and their potential role to enhance plant growth.

    Science.gov (United States)

    Liu, Xue; Feng, Hua-Yuan; Fu, Jing-Wei; Chen, Yanshan; Liu, Yungen; Ma, Lena Q

    2018-05-01

    It is known that arsenic (As) promotes growth of As-hyperaccumulator Pteris vittata (PV), however, the associated mechanisms are unclear. Here we examined As-induced nutrient uptake in P. vittata and their potential role to enhance plant growth in sterile agar by excluding microbial effects. As-hyperaccumulator P. multifida (PM) and non-hyperaccumulator P. ensiformis (PE) belonging to the Pteris genus were used as comparisons. The results showed that, after 40 d of growth, As induced biomass increase in hyperaccumulators PV and PM by 5.2-9.4 fold whereas it caused 63% decline in PE. The data suggested that As played a beneficial role in promoting hyperaccumulator growth. In addition, hyperaccumulators PV and PM accumulated 7.5-13, 1.4-3.6, and 1.8-4.4 fold more As, Fe, and P than the non-hyperaccumulator PE. In addition, nutrient contents such as K and Zn were also increased while Ca, Mg, and Mn decreased or unaffected under As treatment. This study demonstrated that As promoted growth in hyperaccumulators and enhanced Fe, P, K, and Zn uptake. Different plant growth responses to As among hyperaccumulators PV and PM and non-hyperaccumulator PE may help to better understand why hyperaccumulators grow better under As-stress. Published by Elsevier Ltd.

  6. A review on environmental factors regulating arsenic methylation in humans

    International Nuclear Information System (INIS)

    Tseng, C.-H.

    2009-01-01

    Subjects exposed to arsenic show significant inter-individual variation in urinary patterns of arsenic metabolites but insignificant day-to-day intra-individual variation. The inter-individual variation in arsenic methylation can be partly responsible for the variation in susceptibility to arsenic toxicity. Wide inter-ethnic variation and family correlation in urinary arsenic profile suggest a genetic effect on arsenic metabolism. In this paper the environmental factors affecting arsenic metabolism are reviewed. Methylation capacity might reduce with increasing dosage of arsenic exposure. Furthermore, women, especially at pregnancy, have better methylation capacity than their men counterparts, probably due to the effect of estrogen. Children might have better methylation capacity than adults and age shows inconsistent relevance in adults. Smoking and alcohol consumption might be associated with a poorer methylation capacity. Nutritional status is important in the methylation capacity and folate may facilitate the methylation and excretion of arsenic. Besides, general health conditions and medications might influence the arsenic methylation capacity; and technical problems can cause biased estimates. The consumption of seafood, seaweed, rice and other food with high arsenic contents and the extent of cooking and arsenic-containing water used in food preparation may also interfere with the presentation of the urinary arsenic profile. Future studies are necessary to clarify the effects of the various arsenic metabolites including the trivalent methylated forms on the development of arsenic-induced human diseases with the consideration of the effects of confounding factors and the interactions with other effect modifiers

  7. Determination of leachable arsenic from glass ampoules

    International Nuclear Information System (INIS)

    Kayasth, S.R.; Swain, K.K.

    2004-01-01

    Appreciable amounts of different arsenic compounds are used in the manufacture of glass and glass ampoules (injection vials and bottles) used to store drugs. Exposure/intake of arsenic to human beings may result in skin ulceration, injury to mucous membranes, perforation of nasal septum, skin cancer and keratoses, especially of the palms and soles and may cause detrimental effects. Considering the toxicity of arsenic, even if traces of arsenic from such glass containers/ampoules are leached out, it can impart damage to human beings. To check the possibility of leaching of arsenic from glass ampoules, a simple methodology has been developed. Different makes and varieties of glass ampoules filled with de-ionized water were subjected to high pressure and temperature leaching for varying amount of time using autoclave to create extreme conditions for the maximum leaching out of the analyte. Subsequently, the determination of the arsenic contents in leached water using neutron activation analysis is reported in detail with observations. (author)

  8. Isolation of Arsenic Resistant Escherichia coli from Sewage Water and Its Potential in Arsenic Biotransformation

    Directory of Open Access Journals (Sweden)

    Basanta Bista

    2017-04-01

    Full Text Available Arsenic contamination in drinking water from ground water poses a threat to the health of a large population in developing countries in Asia. This has sparked great interests in the potential of different microbes in arsenic resistance and removal from water. This study involves isolation of arsenic resistant Escherichia coli from sewage water from Kathmandu University and investigation of its attributes. Arsenic resistant E. coli was successfully isolated which could survive in high concentration of arsenic. The maximum tolerance of arsenite was 909.79 mg/L (sodium arsenite and 3120.1 mg/L arsenate (sodium arsenate which is well above most natural concentration of arsenic in ground water. This particular E. coli tolerated multiple heavy metal like silver nitrate, cobalt sulphate, cadmium chloride, nickel chloride, mercury chloride, copper sulphate, and zinc chloride at concentration 20 µM, 1 mM, 0.5mM, 1mM, 0.01 mM, 1 mM, and 1 mM respectively which are concentrations known to be toxic to E. coli. Biotransformation of arsenite to arsenate was also checked for by a qualitative silver nitrate technique. This E. coli was able to transform arsenate to arsenite. It showed some sensitivity to Ciprofloxacin, Gentamicin and Nalidixic Acid. As E. coli and its genome are very widely studied, these particular properties have a lot of potential in microbial remediation or microbial recovery of metals and possible recombination approaches.

  9. Development of suitable hydroponics system for phytoremediation of arsenic-contaminated water using an arsenic hyperaccumulator plant Pteris vittata.

    Science.gov (United States)

    Huang, Yi; Miyauchi, Keisuke; Inoue, Chihiro; Endo, Ginro

    2016-01-01

    In this study, we found that high-performance hydroponics of arsenic hyperaccumulator fern Pteris vittata is possible without any mechanical aeration system, if rhizomes of the ferns are kept over the water surface level. It was also found that very low-nutrition condition is better for root elongation of P. vittata that is an important factor of the arsenic removal from contaminated water. By the non-aeration and low-nutrition hydroponics for four months, roots of P. vittata were elongated more than 500 mm. The results of arsenate phytofiltration experiments showed that arsenic concentrations in water declined from the initial concentrations (50 μg/L, 500 μg/L, and 1000 μg/L) to lower than the detection limit (0.1 μg/L) and about 80% of arsenic removed was accumulated in the fern fronds. The improved hydroponics method for P. vittata developed in this study enables low-cost phytoremediation of arsenic-contaminated water and high-affinity removal of arsenic from water.

  10. Arsenic induces structural and compositional colonic microbiome change and promotes host nitrogen and amino acid metabolism

    International Nuclear Information System (INIS)

    Dheer, Rishu; Patterson, Jena; Dudash, Mark; Stachler, Elyse N.; Bibby, Kyle J.; Stolz, Donna B.; Shiva, Sruti; Wang, Zeneng; Hazen, Stanley L.; Barchowsky, Aaron; Stolz, John F.

    2015-01-01

    Chronic exposure to arsenic in drinking water causes cancer and non-cancer diseases. However, mechanisms for chronic arsenic-induced pathogenesis, especially in response to lower exposure levels, are unclear. In addition, the importance of health impacts from xeniobiotic-promoted microbiome changes is just being realized and effects of arsenic on the microbiome with relation to disease promotion are unknown. To investigate impact of arsenic exposure on both microbiome and host metabolism, the stucture and composition of colonic microbiota, their metabolic phenotype, and host tissue and plasma metabolite levels were compared in mice exposed for 2, 5, or 10 weeks to 0, 10 (low) or 250 (high) ppb arsenite (As(III)). Genotyping of colonic bacteria revealed time and arsenic concentration dependent shifts in community composition, particularly the Bacteroidetes and Firmicutes, relative to those seen in the time-matched controls. Arsenic-induced erosion of bacterial biofilms adjacent to the mucosal lining and changes in the diversity and abundance of morphologically distinct species indicated changes in microbial community structure. Bacterical spores increased in abundance and intracellular inclusions decreased with high dose arsenic. Interestingly, expression of arsenate reductase (arsA) and the As(III) exporter arsB, remained unchanged, while the dissimilatory nitrite reductase (nrfA) gene expression increased. In keeping with the change in nitrogen metabolism, colonic and liver nitrite and nitrate levels and ratios changed with time. In addition, there was a concomitant increase in pathogenic arginine metabolites in the mouse circulation. These data suggest that arsenic exposure impacts the microbiome and microbiome/host nitrogen metabolism to support disease enhancing pathogenic phenotypes. - Highlights: • Arsenic exposure induces changes in host and host nitrogen metabolism that cause progresive change in the microbiome. • A polyphasic approach reveals changes

  11. Arsenic induces structural and compositional colonic microbiome change and promotes host nitrogen and amino acid metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Dheer, Rishu; Patterson, Jena; Dudash, Mark [Department of Biological Sciences, Duquesne University, Pittsburgh, PA 15282 (United States); Stachler, Elyse N.; Bibby, Kyle J. [Department of Civil and Environmental Engineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, PA 15261 (United States); Stolz, Donna B. [Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261 (United States); Shiva, Sruti [Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh 15261 (United States); Vascular Medicine Institute, University of Pittsburgh, Pittsburgh 15261 (United States); Wang, Zeneng; Hazen, Stanley L. [Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195 (United States); Barchowsky, Aaron, E-mail: aab20@pitt.edu [Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh 15261 (United States); Vascular Medicine Institute, University of Pittsburgh, Pittsburgh 15261 (United States); Department of Environmental and Occupational Health, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA 15219 (United States); Stolz, John F. [Department of Biological Sciences, Duquesne University, Pittsburgh, PA 15282 (United States)

    2015-12-15

    Chronic exposure to arsenic in drinking water causes cancer and non-cancer diseases. However, mechanisms for chronic arsenic-induced pathogenesis, especially in response to lower exposure levels, are unclear. In addition, the importance of health impacts from xeniobiotic-promoted microbiome changes is just being realized and effects of arsenic on the microbiome with relation to disease promotion are unknown. To investigate impact of arsenic exposure on both microbiome and host metabolism, the stucture and composition of colonic microbiota, their metabolic phenotype, and host tissue and plasma metabolite levels were compared in mice exposed for 2, 5, or 10 weeks to 0, 10 (low) or 250 (high) ppb arsenite (As(III)). Genotyping of colonic bacteria revealed time and arsenic concentration dependent shifts in community composition, particularly the Bacteroidetes and Firmicutes, relative to those seen in the time-matched controls. Arsenic-induced erosion of bacterial biofilms adjacent to the mucosal lining and changes in the diversity and abundance of morphologically distinct species indicated changes in microbial community structure. Bacterical spores increased in abundance and intracellular inclusions decreased with high dose arsenic. Interestingly, expression of arsenate reductase (arsA) and the As(III) exporter arsB, remained unchanged, while the dissimilatory nitrite reductase (nrfA) gene expression increased. In keeping with the change in nitrogen metabolism, colonic and liver nitrite and nitrate levels and ratios changed with time. In addition, there was a concomitant increase in pathogenic arginine metabolites in the mouse circulation. These data suggest that arsenic exposure impacts the microbiome and microbiome/host nitrogen metabolism to support disease enhancing pathogenic phenotypes. - Highlights: • Arsenic exposure induces changes in host and host nitrogen metabolism that cause progresive change in the microbiome. • A polyphasic approach reveals changes

  12. Bacteria, hypertolerant to arsenic in the rocks of an ancient gold mine, and their potential role in dissemination of arsenic pollution.

    Science.gov (United States)

    Drewniak, Lukasz; Styczek, Aleksandra; Majder-Lopatka, Malgorzata; Sklodowska, Aleksandra

    2008-12-01

    The aim of the present study was to find out if bacteria present in ancient gold mine could transform immobilized arsenic into its mobile form and increase its dissemination in the environment. Twenty-two arsenic-hypertolerant cultivable bacterial strains were isolated. No chemolithoautotrophs, which could use arsenite as an electron donor as well as arsenate as an electron acceptor, were identified. Five isolates exhibited hypertolerance to arsenic: up to 500mM of arsenate. A correlation between the presence of siderophores and high resistance to arsenic was found. The results of this study show that detoxification processes based on arsenate reductase activity might be significant in dissemination of arsenic pollution. It was concluded that the activity of the described heterotrophic bacteria contributes to the mobilization of arsenic in the more toxic As(III) form and a new mechanism of arsenic mobilization from a scorodite was proposed.

  13. Arsenic in North Carolina: public health implications.

    Science.gov (United States)

    Sanders, Alison P; Messier, Kyle P; Shehee, Mina; Rudo, Kenneth; Serre, Marc L; Fry, Rebecca C

    2012-01-01

    Arsenic is a known human carcinogen and relevant environmental contaminant in drinking water systems. We set out to comprehensively examine statewide arsenic trends and identify areas of public health concern. Specifically, arsenic trends in North Carolina private wells were evaluated over an eleven-year period using the North Carolina Department of Health and Human Services database for private domestic well waters. We geocoded over 63,000 domestic well measurements by applying a novel geocoding algorithm and error validation scheme. Arsenic measurements and geographical coordinates for database entries were mapped using Geographic Information System techniques. Furthermore, we employed a Bayesian Maximum Entropy (BME) geostatistical framework, which accounts for geocoding error to better estimate arsenic values across the state and identify trends for unmonitored locations. Of the approximately 63,000 monitored wells, 7712 showed detectable arsenic concentrations that ranged between 1 and 806μg/L. Additionally, 1436 well samples exceeded the EPA drinking water standard. We reveal counties of concern and demonstrate a historical pattern of elevated arsenic in some counties, particularly those located along the Carolina terrane (Carolina slate belt). We analyzed these data in the context of populations using private well water and identify counties for targeted monitoring, such as Stanly and Union Counties. By spatiotemporally mapping these data, our BME estimate revealed arsenic trends at unmonitored locations within counties and better predicted well concentrations when compared to the classical kriging method. This study reveals relevant information on the location of arsenic-contaminated private domestic wells in North Carolina and indicates potential areas at increased risk for adverse health outcomes. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Arsenic species in ecosystems affected by arsenic-rich spring water near an abandoned mine in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y.T. [Department of Earth System Science, Yonsei University, 134 Shinchon-Dong, Sudaemoon-Gu, Seoul 120-749 (Korea, Republic of); Nano Environment Materials Research Team, Korea Basic Science Institute, Seoul 136-600 (Korea, Republic of); Yoon, H.O., E-mail: dunee@kbsi.re.k [Nano Environment Materials Research Team, Korea Basic Science Institute, Seoul 136-600 (Korea, Republic of); Yoon, C. [Nano Environment Materials Research Team, Korea Basic Science Institute, Seoul 136-600 (Korea, Republic of); Woo, N.C., E-mail: ncwoo@yonsei.ac.k [Department of Earth System Science, Yonsei University, 134 Shinchon-Dong, Sudaemoon-Gu, Seoul 120-749 (Korea, Republic of)

    2009-12-15

    The objectives of this study were to quantitatively estimate the distribution of arsenic with its speciation and to identify potential pathways for transformation of arsenic species from samples of water, sediments, and plants in the ecosystem affected by the Cheongog Spring, where As(V) concentration reached levels up to 0.270 mg L{sup -1}. After flowing about 100 m downstream, the arsenic level showed a marked reduction to 0.044 mg L{sup -1} (about 84% removal) without noticeable changes in major water chemistry. The field study and laboratory hydroponic experiments with the dominant emergent plants along the creek (water dropwort and thunbergian smartweed) indicated that arsenic distribution, reduction, and speciation appear to be controlled by, (i) sorption onto stream sediments in exchangeable fractions, (ii) bioaccumulation by and possible release from emergent plants, and (iii) transformation of As(V) to As(III) and organic species through biological activities. - Biogeochemical reactions with emergent plants and sediments control the fate of arsenic along creeks originating from a high-As Spring.

  15. Effect of edta on arsenic phytoextraction by arundo donax

    International Nuclear Information System (INIS)

    Mirza, N.; Pervez, A.; Mahmood, Q.; Shah, M.M.; Farooq, U.

    2014-01-01

    Ligand assisted metal uptake by plants is recent trend in environmental clean-up. Arundo donax L. has been demonstrated as a suitable bioresource for the phytoextraction of arsenic recently. A. donax L. plants were grown in arsenic contaminated soil with doses (5 and 10 mg kg/sup -1/) of Ethylene Diamine Tetra Acetic Acid (EDTA) to investigate chelator-assisted phytoextraction. The arsenic treatments included control (no metal) and five doses of arsenic, i.e., 50, 100, 300, 600 and 1000 micro g kg/sup -1/ . The arsenic concentrations linearly increased in parts of plant with the increasing arsenic and EDTA in growth medium. Ligand addition also resulted in the increased arsenic accumulation in the shoot over its control plants. EDTA additionat the rate 5 mg kg/sup -1/ to the treatment system may effectively increase the arsenic uptake by A. donax without severe growth suppression. (author)

  16. Arsenic speciation in arsenic-rich Brazilian soils from gold mining sites under anaerobic incubation

    Science.gov (United States)

    De Mello, J. W. V.; Talbott, J.L.; Scott, J.; Roy, W.R.; Stucki, J.W.

    2007-01-01

    Background. Arsenic speciation in environmental samples is essential for studying toxicity, mobility and bio-transformation of As in aquatic and terrestrial environments. Although the inorganic species As(III) and As(V) have been considered dominant in soils and sediments, organisms are able to metabolize inorganic forms of arsenic into organo-arsenic compounds. Arsenosugars and methylated As compounds can be found in terrestrial organisms, but they generally occur only as minor constituents. We investigated the dynamics of arsenic species under anaerobic conditions in soils surrounding gold mining areas from Minas Gerais State, Brazil to elucidate the arsenic biogeochemical cycle and water contamination mechanisms. Methods. Surface soil samples were collected at those sites, namely Paracatu Formation, Banded Iron Formation and Riacho dos Machados Sequence, and incubated in CaCl2 2.5 mmol L-1 suspensions under anaerobic conditions for 1, 28, 56 and 112 days. After that, suspensions were centrifuged and supernatants analyzed for soluble As species by IC-ICPMS and HPLC-ICPMS. Results. Easily exchangeable As was mainly arsenite, except when reducible manganese was present. Arsenate was mainly responsible for the increase in soluble arsenic due to the reductive dissolution of either iron or manganese in samples from the Paracatu Formation and Riacho dos Machados Sequence. On the other hand, organic species of As dominated in samples from the Banded Iron Formation during anaerobic incubation. Discussion. Results are contrary to the expectation that, in anaerobic environments, As release due to the reductive dissolution of Fe is followed by As(V) reduction to As(III). The occurrence of organo-arsenic species was also found to be significant to the dynamics of soluble arsenic, mainly in soils from the Banded Iron Formation (BIF), under our experimental conditions. Conclusions. In general, As(V) and organic As were the dominant species in solution, which is surprising

  17. Effects of Carbon in Flooded Paddy Soils: Implications for Microbial Activity and Arsenic Mobilization

    Science.gov (United States)

    Avancha, S.; Boye, K.

    2014-12-01

    In the Mekong delta in Cambodia, naturally occurring arsenic (originating from erosion in the Himalaya Mountains) in paddy soils is mobilized during the seasonal flooding. As a consequence, rice grown on the flooded soils may take up arsenic and expose people eating the rice to this carcinogenic substance. Microbial activity will enhance or decrease the mobilization of arsenic depending on their metabolic pathways. Among the microbes naturally residing in the soil are denitrifying bacteria, sulfate reducers, metal reducers (Fe, Mn), arsenic reducers, methanogens, and fermenters, whose activity varies based on the presence of oxygen. The purpose of the experiment was to assess how different amendments affect the microbial activity and the arsenic mobilization during the transition from aerobic to anaerobic metabolism after flooding of naturally contaminated Cambodian soil. In a batch experiment, we investigated how the relative metabolic rate of naturally occurring microbes could vary with different types of organic carbon. The experiment was designed to measure the effects of various sources of carbon (dried rice straw, charred rice straw, manure, and glucose) on the microbial activity and arsenic release in an arsenic-contaminated paddy soil from Cambodia under flooded conditions. All amendments were added based on the carbon content in order to add 0.036 g of carbon per vial. The soil was flooded with a 10mM TRIS buffer solution at pH 7.04 in airtight 25mL serum vials and kept at 25 °C. We prepared 14 replicates per treatment to sample both gas and solution. On each sampling point, the solution replicates were sampled destructively. The gas replicates continued on and were sampled for both gas and solution on the final day of the experiment. We measured pH, total arsenic, methane, carbon dioxide, and nitrous oxide at 8 hours, 1.5 days, 3.33 days, and 6.33 days from the start of the experiment.

  18. DETERMINATION OF URINARY TRIVALENT ARSENICALS (MMASIII AND DMASIII) IN INDIVIDUALS CHRONICALLY EXPOSED TO ARSENIC

    Science.gov (United States)

    DETERMINATION OF URINARY TRIVALENT ARSENICALS (MMAsIII and DMAsIII) IN INDIVIDUALS CHRONICALLY EXPOSED TO ARSENIC. L. M. Del Razo1, M. Styblo2, W. R. Cullen3, and D.J. Thomas4. 1Toxicology Section, Cinvestav-IPN, Mexico, D.F., 2Univ. North Carolina, Chapel Hill, NC; 3Uni...

  19. Arsenic efflux from Microcystis aeruginosa under different phosphate regimes.

    Directory of Open Access Journals (Sweden)

    Changzhou Yan

    Full Text Available Phytoplankton plays an important role in arsenic speciation, distribution, and cycling in freshwater environments. Little information, however, is available on arsenic efflux from the cyanobacteria Microcystis aeruginosa under different phosphate regimes. This study investigated M. aeruginosa arsenic efflux and speciation by pre-exposing it to 10 µM arsenate or arsenite for 24 h during limited (12 h and extended (13 d depuration periods under phosphate enriched (+P and phosphate depleted (-P treatments. Arsenate was the predominant species detected in algal cells throughout the depuration period while arsenite only accounted for no greater than 45% of intracellular arsenic. During the limited depuration period, arsenic efflux occurred rapidly and only arsenate was detected in solutions. During the extended depuration period, however, arsenate and dimethylarsinic acid (DMA were found to be the two predominant arsenic species detected in solutions under -P treatments, but arsenate was the only species detected under +P treatments. Experimental results also suggest that phosphorus has a significant effect in accelerating arsenic efflux and promoting arsenite bio-oxidation in M. aeruginosa. Furthermore, phosphorus depletion can reduce arsenic efflux from algal cells as well as accelerate arsenic reduction and methylation. These findings can contribute to our understanding of arsenic biogeochemistry in aquatic environments and its potential environmental risks under different phosphorus levels.

  20. Magentite nanoparticle for arsenic remotion

    International Nuclear Information System (INIS)

    Viltres, H; Reguera, E; Odio, O F; Borja, R; Aguilera, Y

    2017-01-01

    Inorganic As (V) and As (III) species are commonly found in groundwater in many countries around the world. It is known that arsenic is highly toxic and carcinogenic, at present exist reports of diverse countries with arsenic concentrations in drinking water higher than those proposed by the World Health Organization (10 μg/L). It has been reported that adsorption strategies using magnetic nanoparticles as magnetite (<20 nm) proved to be very efficient for the removal of arsenic in drinking water. Magnetic nanoparticles (magnetite) were prepared using a co-precipitation method with FeCl 3 and FeCl 2 as metal source and NaOH aqueous solution as precipitating agent. Magnetite nanoparticles synthesized were put in contact with As 2 O 3 and As 2 O 5 solutions at room temperature to pH 4 and 7. The nanoparticles were characterized by FT-IR, DRX, UV-vis, and XRF. The results showed that synthesized magnetite had an average diameter of 11 nm and a narrow size distribution. The presence of arsenic on magnetite nanoparticles surface was confirmed, which is more remarkable when As (V) is employed. Besides, it is possible to observe that no significant changes in the band gap values after adsorption of arsenic in the nanoparticles. (paper)

  1. Root development during soil genesis: effects of root-root interactions, mycorrhizae, and substrate

    Science.gov (United States)

    Salinas, A.; Zaharescu, D. G.

    2015-12-01

    A major driver of soil formation is the colonization and transformation of rock by plants and associated microbiota. In turn, substrate chemical composition can also influence the capacity for plant colonization and development. In order to better define these relationships, a mesocosm study was set up to analyze the effect mycorrhizal fungi, plant density and rock have on root development, and to determine the effect of root morphology on weathering and soil formation. We hypothesized that plant-plant and plant-fungi interactions have a stronger influence on root architecture and rock weathering than the substrate composition alone. Buffalo grass (Bouteloua dactyloides) was grown in a controlled environment in columns filled with either granular granite, schist, rhyolite or basalt. Each substrate was given two different treatments, including grass-microbes and grass-microbes-mycorrhizae and incubated for 120, 240, and 480 days. Columns were then extracted and analyzed for root morphology, fine fraction, and pore water major element content. Preliminary results showed that plants produced more biomass in rhyolite, followed by schist, basalt, and granite, indicating that substrate composition is an important driver of root development. In support of our hypothesis, mycorrhizae was a strong driver of root development by stimulating length growth, biomass production, and branching. However, average root length and branching also appeared to decrease in response to high plant density, though this trend was only present among roots with mycorrhizal fungi. Interestingly, fine fraction production was negatively correlated with average root thickness and volume. There is also slight evidence indicating that fine fraction production is more related to substrate composition than root morphology, though this data needs to be further analyzed. Our hope is that the results of this study can one day be applied to agricultural research in order to promote the production of crops

  2. Sedimentology and arsenic pollution in the Bengal Basin: insight into arsenic occurrence and subsurface geology.

    Science.gov (United States)

    Hills, Andrew; McArthur, John

    2014-05-01

    The Bengal delta system is a geologically recent feature overlying a deeply incised palaeo-surface formed during the Last Glacial Maximum. This surface is a series of terraces and valleys created by river incision (Goodbred & Kuehl 2003). The terraces were weathered, forming a thin, indurated laterite deposit (Goodbred & Kuehl 2000) at depths greater than 50 m. McArthur et al. (2008) define this as a palaeosol and have identified it at depths greater than 30 m though out Bangladesh and West Bengal. It has been observed that arsenic concentrations at these sites are lower than the rest of the delta. It has been assumed that the surface morphology at sites where there is a palaeosol are similar and can therefore be characterised by remote sensing, in the form of Google Earth images. Sites were selected in Bangladesh and West Bengal, from work by McArthur et al. (2011); Hoque et al. (2012), where groundwater chemistry and sedimentology data are available making it possible to determine if the subsurface is a palaeo-channel or palaeo-interfluve. Arsenic concentration data have been inputted into Google Earth and the palaeo-channels marked where the arsenic concentration is greater than 10 µg/L, and palaeo-interfluves where arsenic concentration is less than 10 µg/L. The surface morphologies in these domains have been examined for similarities, and it was shown that avulsion scars and abandoned river channels are found where arsenic concentrations are greater than 10 µg/L. Conversely the surrounding areas that are devoid of channel scars have arsenic concentrations less than 10 µg/L. Using the correlation between avulsion features being representative of palaeo-channels and high arsenic concentrations, sites were selected that had a similar surface morphology to the type localities. A comparison of these images and arsenic concentrations showed that the postulate is valid for over 80 percent of cases. Where this is not valid, this could indicate that the subsurface

  3. Arsenic in Ground Water of the United States

    Science.gov (United States)

    ... Team More Information Arsenic in groundwater of the United States Arsenic in groundwater is largely the result of ... Gronberg (2011) for updated arsenic map. Featured publications United States Effects of human-induced alteration of groundwater flow ...

  4. [Arsenic - Poison or medicine?].

    Science.gov (United States)

    Kulik-Kupka, Karolina; Koszowska, Aneta; Brończyk-Puzoń, Anna; Nowak, Justyna; Gwizdek, Katarzyna; Zubelewicz-Szkodzińska, Barbara

    2016-01-01

    Arsenic (As) is commonly known as a poison. Only a few people know that As has also been widely used in medicine. In the past years As and its compounds were used as a medicine for the treatment of such diseases as diabetes, psoriasis, syphilis, skin ulcers and joint diseases. Nowadays As is also used especially in the treatment of patients with acute promyelocytic leukemia. The International Agency for Research on Cancer (IARC) has recognized arsenic as an element with carcinogenic effect evidenced by epidemiological studies, but as previously mentioned it is also used in the treatment of neoplastic diseases. This underlines the specificity of the arsenic effects. Arsenic occurs widely in the natural environment, for example, it is present in soil and water, which contributes to its migration to food products. Long exposure to this element may lead to liver damages and also to changes in myocardium. Bearing in mind that such serious health problems can occur, monitoring of the As presence in the environmental media plays a very important role. In addition, the occupational risk of As exposure in the workplace should be identified and checked. Also the standards for As presence in food should be established. This paper presents a review of the 2015 publications based on the Medical database like PubMed and Polish Medical Bibliography. It includes the most important information about arsenic in both forms, poison and medicine. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  5. Arsenic metabolites in humans after ingestion of wakame seaweed

    Directory of Open Access Journals (Sweden)

    Hata A.

    2013-04-01

    Full Text Available Seaweed contains large amounts of various arsenic compounds such as arsenosugars (AsSugs, but their relative toxicities have not yet been fully evaluated. A risk evaluation of dietary arsenic would be necessary. After developing an arsenic speciation analysis of wakame seaweed (Undaria pinnatifida, we conducted a wakame ingestion experiment using volunteers. Five volunteers ingested 300 g of commercial wakame after refraining from seafood for 5 days. Arsenic metabolites in the urine were monitored over a 5-day period after ingestion. Total arsenic concentration of the wakame seaweed was 34.3 ± 2.1 mg arsenic/kg (dry weight, n = 3. Two AsSugs, 3-[5′-deoxy-5′-(dimethyl-arsinoyl-β-ribofuranosyloxy]-propylene glycol (AsSug328 and 3-[5′-deoxy-5′-(dimethyl-arsinoyl-β- ribofuranosyl-oxy]-2-hydroxypropyl-2,3-dihydroxy-propyl phosphate (AsSug482 were detected, but arsenobetaine, dimethylarsinic acid (DMA, monomethylarsonic acid, and inorganic arsenics (iAs were not detected. The major peak was AsSug328, which comprised 89% of the total arsenic. Approximately 30% of the total arsenic ingested was excreted in the urine during the 5-day observation. Five arsenic compounds were detected in the urine after ingestion, the major one being DMA, which comprised 58.1 ± 5.0% of the total urinary arsenic excreted over the 5 days. DMA was believed to be metabolized not from iAs but from AsSugs, and its biological half-time was approximately 13 h.

  6. Regenerating an Arsenic Removal Iron-Based Adsorptive ...

    Science.gov (United States)

    The replacement of exhausted, adsorptive media used to remove arsenic from drinking water accounts for approximately 80% of the total operational and maintenance (O/M) costs of this commonly used small system technology. The results of three, full scale system studies of an on-site media regeneration process (Part 1) showed it to be effective in stripping arsenic and other contaminants from the exhausted media. Part 2, of this two part paper, presents information on the performance of the regenerated media to remove arsenic through multiple regeneration cycles (3) and the approximate cost savings of regeneration over media replacement. The results of the studies indicate that regenerated media is very effective in removing arsenic and the regeneration cost is substantially less than the media replacement cost. On site regeneration, therefore, provides small systems with alternative to media replacement when removing arsenic from drinking water using adsorptive media technology. Part 2 of a two part paper on the performance of the regenerated media to remove arsenic through multiple regeneration cycles (3) and the approximate cost savings of regeneration over media replacement.

  7. TREATMENT TECHNOLOGIES FOR ARSENIC REMOVAL

    Science.gov (United States)

    The United States Environmental Protection Agency (US EPA) recently reduced the arsenic maximum contaminant level (MCL) from 0.050 mg/L to 0.010 mg/L. In order to increase arsenic outreach efforts, a summary of the new rule, related health risks, treatment technologies, and desig...

  8. Effects of Nrf2 deficiency on arsenic metabolism in mice.

    Science.gov (United States)

    Wang, Huihui; Zhu, Jiayu; Li, Lu; Li, Yongfang; Lv, Hang; Xu, Yuanyuan; Sun, Guifan; Pi, Jingbo

    2017-12-15

    Inorganic arsenic (iAs) is a known toxicant and carcinogen. Worldwide arsenic exposure has become a threat to human health. The severity of arsenic toxicity is strongly correlated with the speed of arsenic metabolism (methylation) and clearance. Furthermore, oxidative stress is recognized as a major mechanism for arsenic-induced toxicity. Nuclear factor-E2-related factor 2 (Nrf2), a key regulator in cellular adaptive antioxidant response, is clearly involved in alleviation of arsenic-induced oxidative damage. Multiple studies demonstrate that Nrf2 deficiency mice are more vulnerable to arsenic-induced intoxication. However, what effect Nrf2 deficiency might have on arsenic metabolism in mice is still unknown. In the present study, we measured the key enzymes involved in arsenic metabolism in Nrf2-WT and Nrf2-KO mice. Our results showed that basal transcript levels of glutathione S-transferase omega 2 (Gsto2) were significantly higher and GST mu 1 (Gstm1) lower in Nrf2-KO mice compared to Nrf2-WT control. Arsenic speciation and methylation rate in liver and urine was then studied in mice treated with 5mg/kg sodium arsenite for 12h. Although there were some alterations in arsenic metabolism enzymes between Nrf2-WT and Nrf2-KO mice, the Nrf2 deficiency had no significant effect on arsenic methylation. These results suggest that the Nrf2-KO mice are more sensitive to arsenic than Nrf2-WT mainly because of differences in adaptive antioxidant detoxification capacity rather than arsenic methylation capacity. Copyright © 2017. Published by Elsevier Inc.

  9. Establishment of Groundwater Arsenic Potential Distribution and Discrimination in Taiwan

    Science.gov (United States)

    Tsai, Kuo Sheng; Chen, Yu Ying; Chung Liu, Chih; Lin, Chien Wen

    2016-04-01

    According to the last 10 years groundwater monitoring data in Taiwan, Arsenic concentration increase rapidly in some areas, similar to Bengal and India, the main source of Arsenic-polluted groundwater is geological sediments, through reducing reactions. There are many researches indicate that high concentration of Arsenic in groundwater poses the risk to water safety, for example, the farm lands irrigation water contains Arsenic cause the concentration of Arsenic increase in soil and crops. Based on the management of water usage instead of remediation in the situation of insufficient water. Taiwan EPA has been developed the procedures of Arsenic contamination potential area establishment and source discriminated process. Taiwan EPA use the procedures to determine the management of using groundwater, and the proposing usage of Arsenic groundwater accordance with different objects. Agencies could cooperate with the water quality standard or water needs, studying appropriate water purification methods and the groundwater depth, water consumption, thus achieve the goal of water safety and environmental protection, as a reference of policy to control total Arsenic concentration in groundwater. Keywords: Arsenic; Distribution; Discrimination; Pollution potential area of Arsenic; Origin evaluation of groundwater Arsenic

  10. The Case for Visual Analytics of Arsenic Concentrations in Foods

    Directory of Open Access Journals (Sweden)

    Omotayo R. Awofolu

    2010-04-01

    Full Text Available Arsenic is a naturally occurring toxic metal and its presence in food could be a potential risk to the health of both humans and animals. Prolonged ingestion of arsenic contaminated water may result in manifestations of toxicity in all systems of the body. Visual Analytics is a multidisciplinary field that is defined as the science of analytical reasoning facilitated by interactive visual interfaces. The concentrations of arsenic vary in foods making it impractical and impossible to provide regulatory limit for each food. This review article presents a case for the use of visual analytics approaches to provide comparative assessment of arsenic in various foods. The topics covered include (i metabolism of arsenic in the human body; (ii arsenic concentrations in various foods; (ii factors affecting arsenic uptake in plants; (ii introduction to visual analytics; and (iv benefits of visual analytics for comparative assessment of arsenic concentration in foods. Visual analytics can provide an information superstructure of arsenic in various foods to permit insightful comparative risk assessment of the diverse and continually expanding data on arsenic in food groups in the context of country of study or origin, year of study, method of analysis and arsenic species.

  11. ARSENIC IN DRINKING WATER SUPPLY WELLS: A MULTI ...

    Science.gov (United States)

    Studies have indicated that arsenic concentrations greater than the new U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) concentration of 10 micrograms per liter (µg/L) occur in numerous aquifers around the United States. One such aquifer is the Central Oklahoma aquifer, which supplies drinking water to numerous communities in central Oklahoma. Concentrations as high as 230 µg/L have been reported in some drinking water supply wells from this aquifer. The city of Norman, like most other affected cities, is actively seeking a cost-effective solution to the arsenic problem. Only six of the city’s 32 wells exceeded the old MCL of 50 µg/L. With implementation of the new MCL this year, 18 of the 32 wells exceed the allowable concentration of arsenic. Arsenic-bearing shaly sandstones appear to be the source of the arsenic. It may be possible to isolate these arsenic-bearing zones from water supply wells, enabling production of water that complies with drinking water standards. It is hypothesized that geologic mapping together with detailed hydrogeochemical investigations will yield correlations which predict high arsenic occurrence for the siting of new drinking water production wells. More data and methods to assess the specific distribution, speciation, and mode of transport of arsenic in aquifers are needed to improve our predictions for arsenic occurrence in water supply wells. Research is also needed to assess whether we can ret

  12. Environmental Arsenic Exposure and Microbiota in Induced Sputum

    Directory of Open Access Journals (Sweden)

    Allison G. White

    2014-02-01

    Full Text Available Arsenic exposure from drinking water is associated with adverse respiratory outcomes, but it is unknown whether arsenic affects pulmonary microbiota. This exploratory study assessed the effect of exposure to arsenic in drinking water on bacterial diversity in the respiratory tract of non-smokers. Induced sputum was collected from 10 subjects with moderate mean household water arsenic concentration (21.1 ± 6.4 ppb and 10 subjects with low household water arsenic (2.4 ± 0.8 ppb. To assess microbiota in sputum, the V6 hypervariable region amplicons of bacterial 16s rRNA genes were sequenced using the Ion Torrent Personal Genome Machine. Microbial community differences between arsenic exposure groups were evaluated using QIIME and Metastats. A total of 3,920,441 sequence reads, ranging from 37,935 to 508,787 per sample for 316 chips after QIIME quality filtering, were taxonomically classified into 142 individual genera and five phyla. Firmicutes (22%, Proteobacteria (17% and Bacteriodetes (12% were the main phyla in all samples, with Neisseriaceae (15%, Prevotellaceae (12% and Veillonellacea (7% being most common at the genus level. Some genera, including Gemella, Lactobacillales, Streptococcus, Neisseria and Pasteurellaceae were elevated in the moderate arsenic exposure group, while Rothia, Prevotella, Prevotellaceae Fusobacterium and Neisseriaceae were decreased, although none of these differences was statistically significant. Future studies with more participants and a greater range of arsenic exposure are needed to further elucidate the effects of drinking water arsenic consumption on respiratory microbiota.

  13. Behavior of arsenic impurity at antimony electric precipitation

    International Nuclear Information System (INIS)

    Kim, G.N.; Rakhmanov, A.

    2001-01-01

    In the paper the arsenic impurity electrochemical behavior and it purification from antimony by electric precipitation out of fluoride solutions was studied. For this the arsenic sample with mass 0.003-0.006 g has been irradiated at the WWR-SM nuclear reactor during 3-5 hour in the thermal neutron flux 10 13 n/cm 2 s, after 24 h keeping the sample has being dissolved in the concentrated nitric acid, and then it has been evaporated several times with distillation water addition up to wet precipitation state. It is shown, that arsenic impurity behavior character in the antimony electric precipitation out to fluoride electrolyte depends on the electrolyte content, electrolysis conditions, arsenic valency state in arsenic impurity existence in the five-valency state its joint electric reduction with antimony is practically not observing. In the case the arsenic being in three-valency state, it joint electric reduction with antimony is taking place. In this time the electrolytic antimony contents arsenic impurities less in dozen time than initial material

  14. Assessment of Nutritional Status of Infants Living in Arsenic-Contaminated Areas in Bangladesh and Its Association with Arsenic Exposure

    Science.gov (United States)

    Milton, Abul Hasnat; Attia, John; Alauddin, Mohammad; McEvoy, Mark; McElduff, Patrick; Hussain, Sumaira; Akhter, Ayesha; Akter, Shahnaz; Islam, M. Munirul; Ahmed, AM Shamsir; Iyengar, Vasu; Islam, Md Rafiqul

    2018-01-01

    Data is scarce on early life exposure to arsenic and its association with malnutrition during infancy. This study followed the nutritional status of a cohort of 120 infants from birth to 9 months of age in an arsenic contaminated area in Bangladesh. Anthropometric data was collected at 3, 6 and 9 months of the infant’s age for nutritional assessment whereas arsenic exposure level was assessed via tube well drinking water arsenic concentration at the initiation of the study. Weight and height measurements were converted to Z-scores of weight for age (WAZ-underweight), height for age (HAZ-stunting), weight for height (WHZ-wasting) for children by comparing with WHO growth standard. Arsenic exposure levels were categorized as <50 μg/L and ≥50 μg/L. Stunting rates (<−2 SD) were 10% at 3 months and 44% at both 6 and 9 months. Wasting rates (<−2 SD) were 23.3% at 3 months and underweight rates (<−2 SD) were 25% and 10% at 3 and 6 months of age, respectively. There was a significant association of stunting with household drinking water arsenic exposure ≥50 μg/L at age of 9 months (p = 0.009). Except for stunting at 9 months of age, we did not find any significant changes in other nutritional indices over time or with levels of household arsenic exposure in this study. Our study suggests no association between household arsenic exposure and under-nutrition during infancy; with limiting factors being small sample size and short follow-up. Difference in stunting at 9 months by arsenic exposure at ≥50 μg/L might be a statistical incongruity. Further longitudinal studies are warranted to establish any association. PMID:29301293

  15. Urinary total arsenic and 8-hydroxydeoxyguanosine are associated with renal cell carcinoma in an area without obvious arsenic exposure

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Chao-Yuan [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Department of Urology, National Taiwan University Hospital, College of Medicine National Taiwan University, Taipei, Taiwan (China); Su, Chien-Tien [Department of Family Medicine, Taipei Medical University Hospital, Taipei, Taiwan (China); Chung, Chi-Jung [Department of Health Risk Management, College of Public Health, China Medical University, Taichung, Taiwan (China); Department of Medical Research, China Medical University Hospital, Taichung, Taiwan (China); Pu, Yeong-Shiau [Department of Urology, National Taiwan University Hospital, College of Medicine National Taiwan University, Taipei, Taiwan (China); Chu, Jan-Show [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Department of Pathology, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Yang, Hsiu-Yuan [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Wu, Chia-Chang [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Department of Urology, Taipei Medical Universtiy-Shuang Ho Hospital, Taipei, Taiwan (China); Hsueh, Yu-Mei, E-mail: ymhsueh@tmu.edu.tw [Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China)

    2012-08-01

    8-Hydroxydeoxyguanosine (8-OHdG) is one of the most reliable and abundant markers of DNA damage. The study was designed to explore the relationship between urinary 8-OHdG and renal cell carcinoma (RCC) and to investigate whether individuals with a high level of 8-OHdG would have a modified odds ratio (OR) of arsenic-related RCC. This case–control study was conducted with 132 RCC patients and 245 age- and sex-matched controls from a hospital-based pool between November 2006 and May 2009. Pathological verification of RCC was completed by image-guided biopsy or surgical resection of renal tumors. Urinary 8-OHdG levels were determined using liquid chromatography with tandem mass spectrometry (LC–MS/MS). Concentrations of urinary arsenic species, including inorganic arsenic, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), were determined by a high performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. Level of urinary 8-OHdG was significantly associated with the OR of RCC in a dose–response relationship after multivariate adjustment. Urinary 8-OHdG was significantly related to urinary total arsenic. The greatest OR (3.50) was seen in the individuals with high urinary 8-OHdG and high urinary total arsenic. A trend test indicated that the OR of RCC was increased with one of these factors and was further increased with both (p = 0.002). In conclusion, higher urinary 8-OHdG was a strong predictor of the RCC. High levels of 8-OHdG combined with urinary total arsenic might be indicative of arsenic-induced RCC. -- Highlights: ► Urinary 8-OHdG was significantly related to urinary total arsenic. ► Higher urinary 8-OHdG was a strong predictor of RCC risk. ► Urinary 8-OHdG may modify arsenic related RCC risk.

  16. Arsenic in sediments from the southeastern Baltic Sea

    International Nuclear Information System (INIS)

    Garnaga, Galina; Wyse, Eric; Azemard, Sabine; Stankevicius, Algirdas; Mora, Stephen de

    2006-01-01

    Arsenic occurs as a persistent constituent in many of the chemical weapons dumped into the Baltic Sea; it can be used as an indicator of leakage and dispersal of released munitions to the marine environment. Total arsenic was analysed in sediment samples taken from the Lithuanian economic zone in the Baltic Sea, which included samples from the chemical munitions dumpsite in the Gotland Basin and national monitoring stations in the southeastern Baltic Sea. Arsenic concentrations in sediments ranged from 1.1 to 19.0 mg kg -1 , with an average of 3.4 mg kg -1 . Although there was evidence of slightly elevated arsenic content in sediments near the weapons dumpsite, arsenic concentrations were nevertheless quite low relative to other investigations in the Baltic and North Seas. - Arsenic concentrations in sediments near chemical weapons dumpsites were only slightly elevated

  17. Effects of organic matter and ageing on the bioaccessibility of arsenic

    International Nuclear Information System (INIS)

    Meunier, Louise; Koch, Iris; Reimer, Kenneth J.

    2011-01-01

    Arsenic-contaminated soils may pose a risk to human health. Redevelopment of contaminated sites may involve amending soils with organic matter, which potentially increases arsenic bioaccessibility. The effects of ageing on arsenic-contaminated soils mixed with peat moss were evaluated in a simulated ageing period representing two years, during which arsenic bioaccessibility was periodically measured. Significant increases (p = 0.032) in bioaccessibility were observed for 15 of 31 samples tested, particularly in comparison with samples originally containing >30% bioaccessible arsenic in soils naturally rich in organic matter (>25%). Samples where percent arsenic bioaccessibility was unchanged with age were generally poor in organic matter (average 7.7%) and contained both arsenopyrite and pentavalent arsenic forms that remained unaffected by the organic matter amendments. Results suggest that the addition of organic matter may lead to increases in arsenic bioaccessibility, which warrants caution in the evaluation of risks associated with redevelopment of arsenic-contaminated land. - Highlights: → Adding organic matter to contaminated soils may increase arsenic bioaccessibility. → Ageing soils with >25% organic matter can lead to increased arsenic bioaccessibility. → No changes in arsenic bioaccessibility for soils poor in organic matter (mean 7.7%). → No changes in arsenic bioaccessibility for samples containing arsenopyrite. → Organic matter in soil may favour oxidation of trivalent arsenic to pentavalent form. - Adding organic carbon may increase arsenic bioaccessibility, especially in samples originally containing >30% bioaccessible arsenic in organic carbon-rich soils (>25%).

  18. XAS Studies of Arsenic in the Environment

    International Nuclear Information System (INIS)

    Charnock, J. M.; Polya, D. A.; Gault, A. G.; Morgan, A. J.

    2007-01-01

    Arsenic is present in low concentrations in much of the Earth's crust and changes in its speciation are vital to understanding its transport and toxicity in the environment. We have used X-ray absorption spectroscopy to investigate the coordination sites of arsenic in a wide variety of samples, including soil and earthworm tissues from arsenic-contaminated land, and human hair and nail samples from people exposed to arsenic in Cambodia. Our results confirm the effectiveness of using X-ray absorption near edge structure (XANES) and X-ray absorption fine structure (EXAFS) spectroscopy to determine speciation changes in environmental samples

  19. Analysis of arsenical metabolites in biological samples.

    Science.gov (United States)

    Hernandez-Zavala, Araceli; Drobna, Zuzana; Styblo, Miroslav; Thomas, David J

    2009-11-01

    Quantitation of iAs and its methylated metabolites in biological samples provides dosimetric information needed to understand dose-response relations. Here, methods are described for separation of inorganic and mono-, di-, and trimethylated arsenicals by thin layer chromatography. This method has been extensively used to track the metabolism of the radionuclide [(73)As] in a variety of in vitro assay systems. In addition, a hydride generation-cryotrapping-gas chromatography-atomic absorption spectrometric method is described for the quantitation of arsenicals in biological samples. This method uses pH-selective hydride generation to differentiate among arsenicals containing trivalent or pentavalent arsenic.

  20. Direct determination of arsenic in soil samples by fast pyrolysis–chemical vapor generation using sodium formate as a reductant followed by nondispersive atomic fluorescence spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Xuchuan; Zhang, Jingya; Bu, Fanlong

    2015-09-01

    This new study shows for the first time that sodium formate can react with trace arsenic to form volatile species via fast pyrolysis – chemical vapor generation. We found that the presence of thiourea greatly enhanced the generation efficiency and eliminated the interference of copper. We studied the reaction temperature, the volume of sodium formate, the reaction acidity, and the carried argon rate using nondispersive atomic fluorescence spectrometry. Under optimal conditions of T = 500 °C, the volumes of 30% sodium formate and 10% thiourea were 0.2 ml and 0.05 ml, respectively. The carrier argon rate was 300 ml min{sup −1} and the detection limit and precision of arsenic were 0.39 ng and 3.25%, respectively. The amount of arsenic in soil can be directly determined by adding trace amount of hydrochloric acid as a decomposition reagent without any sample pretreatment. The method was successfully applied to determine trace amount of arsenic in two soil-certified reference materials (GBW07453 and GBW07450), and the results were found to be in agreement with certified reference values. - Highlights: • Sodium formate can react with trace arsenic to form volatile species via pyrolysis–chemical vapor generation. • Thiourea can enhance the generation efficiency and eliminate the interference of copper. • Arsenic in soil Sample can be directly determined without sample pretreatment.

  1. Chronic inorganic arsenic exposure in vitro induces a cancer cell phenotype in human peripheral lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Person, Rachel J.; Olive Ngalame, Ntube N.; Makia, Ngome L.; Bell, Matthew W.; Waalkes, Michael P.; Tokar, Erik J., E-mail: tokare@niehs.nih.gov

    2015-07-01

    Inorganic arsenic is a human lung carcinogen. We studied the ability of chronic inorganic arsenic (2 μM; as sodium arsenite) exposure to induce a cancer phenotype in the immortalized, non-tumorigenic human lung peripheral epithelial cell line, HPL-1D. After 38 weeks of continuous arsenic exposure, secreted matrix metalloproteinase-2 (MMP2) activity increased to over 200% of control, levels linked to arsenic-induced cancer phenotypes in other cell lines. The invasive capacity of these chronic arsenic-treated lung epithelial (CATLE) cells increased to 320% of control and colony formation increased to 280% of control. CATLE cells showed enhanced proliferation in serum-free media indicative of autonomous growth. Compared to control cells, CATLE cells showed reduced protein expression of the tumor suppressor gene PTEN (decreased to 26% of control) and the putative tumor suppressor gene SLC38A3 (14% of control). Morphological evidence of epithelial-to-mesenchymal transition (EMT) occurred in CATLE cells together with appropriate changes in expression of the EMT markers vimentin (VIM; increased to 300% of control) and e-cadherin (CDH1; decreased to 16% of control). EMT is common in carcinogenic transformation of epithelial cells. CATLE cells showed increased KRAS (291%), ERK1/2 (274%), phosphorylated ERK (p-ERK; 152%), and phosphorylated AKT1 (p-AKT1; 170%) protein expression. Increased transcript expression of metallothioneins, MT1A and MT2A and the stress response genes HMOX1 (690%) and HIF1A (247%) occurred in CATLE cells possibly in adaptation to chronic arsenic exposure. Thus, arsenic induced multiple cancer cell characteristics in human peripheral lung epithelial cells. This model may be useful to assess mechanisms of arsenic-induced lung cancer. - Highlights: • Chronic arsenic exposure transforms a human peripheral lung epithelia cell line. • Cells acquire characteristics in common with human lung adenocarcinoma cells. • These transformed cells provide a

  2. Arsenic in Drinking Water-A Global Environmental Problem

    Science.gov (United States)

    Wang, Joanna Shaofen; Wai, Chien M.

    2004-01-01

    Information on the worldwide occurrence of groundwater pollution by arsenic, the ensuing health hazards, and the debatable government regulations of arsenic in drinking water, is presented. Diagnostic identification of arsenic, and methods to eliminate it from water are also discussed.

  3. Screening and characterization of useful microorganisms to arsenic removal

    OpenAIRE

    宮武, 宗利; 林, 幸男

    2007-01-01

    Microorganisms were isolated from soil and their arsenic removal abilities were evaluated. Seven out of the 100 isolated strains showed more than 20% arsenic removal. Time courses of arsenic removal and cell growth were investigated in three of these isolated strains. Although the growth rates were different, the dependence of arsenic removal on cell growth was similar in three strains (A-84, 88, 89). Strain A-89 showed highest arsenic removal rate of 63% after first day. Strain A-88 was best...

  4. Concentrations and chemical species of arsenic in human urine and hair

    Energy Technology Data Exchange (ETDEWEB)

    Yamato, Naohisa (St. Marianna Univ. School of Medicine, Kawasaki (Japan))

    1988-05-01

    Because marine products are rich in arsenic, the concentration of arsenic in the human urine varies greatly with the state of ingestion of marine products. It has been revealed that inorganic arsenic is methylated in the human body to form MAA (methylarsonic acid) and DMAA (dimethylarsinic acid). It appears therefore that the arsenic present in the human urine is a mixture of the arsenic originating from marine products and the arsenic metabolized in vivo. Recent studies have shown that inorganic arsenic and methylarsenic compounds are quite different in toxicity and effect on the living body due to their difference in chemical species. Finding the chemical species of arsenic in the urine and hair of normal subjects will therefore provide valuable basal data for the biological monitoring of arsenic exposure and for toxicological studies of arsenic.

  5. Induction of Human Squamous Cell-Type Carcinomas by Arsenic

    International Nuclear Information System (INIS)

    Martinez, V. D.; Becker-Santos, D. D.; Vucic, E. A.; Lam, S.; Lam, W. L.

    2011-01-01

    Arsenic is a potent human carcinogen. Around one hundred million people worldwide have potentially been exposed to this metalloid at concentrations considered unsafe. Exposure occurs generally through drinking water from natural geological sources, making it difficult to control this contamination. Arsenic biotransformation is suspected to have a role in arsenic-related health effects ranging from acute toxicities to development of malignancies associated with chronic exposure. It has been demonstrated that arsenic exhibits preference for induction of squamous cell carcinomas in the human, especially skin and lung cancer. Interestingly, keratins emerge as a relevant factor in this arsenic-related squamous cell-type preference. Additionally, both genomic and epi genomic alterations have been associated with arsenic-driven neoplastic process. Some of these aberrations, as well as changes in other factors such as keratins, could explain the association between arsenic and squamous cell carcinomas in humans.

  6. Arsenic removal from industrial effluent through electrocoagulation

    Energy Technology Data Exchange (ETDEWEB)

    Balasubramanian, N. [Central Electrochemical Research Inst., Karaikudi (India). Dept. of Pollution Control; Madhavan, K. [Coimbatore Inst. of Technology, Coimbatore (India). Dept. of Chemistry

    2001-05-01

    In the present investigation, it is attempted to remove arsenic from smelter industrial wastewater through electro-coagulation. Experiments covering a wide range of operating conditions for removal of the arsenic present in the smelter wastewater are carried out in a batch electrochemical reactor. It has been observed from the present work that arsenic can be removed effectively through electrocoagulation. (orig.)

  7. Dissolution of arsenic minerals mediated by dissimilatory arsenate reducing bacteria: estimation of the physiological potential for arsenic mobilization.

    Science.gov (United States)

    Lukasz, Drewniak; Liwia, Rajpert; Aleksandra, Mantur; Aleksandra, Sklodowska

    2014-01-01

    The aim of this study was characterization of the isolated dissimilatory arsenate reducing bacteria in the context of their potential for arsenic removal from primary arsenic minerals through reductive dissolution. Four strains, Shewanella sp. OM1, Pseudomonas sp. OM2, Aeromonas sp. OM4, and Serratia sp. OM17, capable of anaerobic growth with As (V) reduction, were isolated from microbial mats from an ancient gold mine. All of the isolated strains: (i) produced siderophores that promote dissolution of minerals, (ii) were resistant to dissolved arsenic compounds, (iii) were able to use the dissolved arsenates as the terminal electron acceptor, and (iii) were able to use copper minerals containing arsenic minerals (e.g., enargite) as a respiratory substrate. Based on the results obtained in this study, we postulate that arsenic can be released from some As-bearing polymetallic minerals (such as copper ore concentrates or middlings) under reductive conditions by dissimilatory arsenate reducers in indirect processes.

  8. Dissolution of Arsenic Minerals Mediated by Dissimilatory Arsenate Reducing Bacteria: Estimation of the Physiological Potential for Arsenic Mobilization

    Directory of Open Access Journals (Sweden)

    Drewniak Lukasz

    2014-01-01

    Full Text Available The aim of this study was characterization of the isolated dissimilatory arsenate reducing bacteria in the context of their potential for arsenic removal from primary arsenic minerals through reductive dissolution. Four strains, Shewanella sp. OM1, Pseudomonas sp. OM2, Aeromonas sp. OM4, and Serratia sp. OM17, capable of anaerobic growth with As (V reduction, were isolated from microbial mats from an ancient gold mine. All of the isolated strains: (i produced siderophores that promote dissolution of minerals, (ii were resistant to dissolved arsenic compounds, (iii were able to use the dissolved arsenates as the terminal electron acceptor, and (iii were able to use copper minerals containing arsenic minerals (e.g., enargite as a respiratory substrate. Based on the results obtained in this study, we postulate that arsenic can be released from some As-bearing polymetallic minerals (such as copper ore concentrates or middlings under reductive conditions by dissimilatory arsenate reducers in indirect processes.

  9. Vascular Hyperpermeability Response in Animals Systemically Exposed to Arsenic.

    Science.gov (United States)

    Chen, Shih-Chieh; Chang, Chao-Yuah; Lin, Ming-Lu

    2018-01-01

    The mechanisms underlying cardiovascular diseases induced by chronic exposure to arsenic remain unclarified. The objectives of this study were to investigate whether increased vascular leakage is induced by inflammatory mustard oil in mice systemically exposed to various doses of arsenic and whether an increased vascular leakage response is still present in arsenic-fed mice after arsenic discontinuation for 2 or 6 months. ICR mice were fed water or various doses of sodium arsenite (10, 15, or 20 mg/kg/day; 5 days/week) for 8 weeks. In separate experiments, the mice were treated with sodium arsenite (20 mg/kg) for 2 or 8 weeks, followed by arsenic discontinuation for 2 or 6 months. Vascular permeability to inflammatory mustard oil was quantified using Evans blue (EB) techniques. Both arsenic-exposed and water-fed (control) mice displayed similar basal levels of EB leakage in the ears brushed with mineral oil, a vehicle of mustard oil. The levels of EB leakage induced by mustard oil in the arsenic groups fed with sodium arsenite (10 or 15 mg/kg) were similar to those of water-fed mice. However, increased levels of EB leakage in response to mustard oil stimulation were significantly higher in mice treated with sodium arsenite (20 mg/kg; high dose) than in arsenic-fed (10 or 15 mg/kg; low and middle doses) or control mice. After arsenic discontinuation for 2 or 6 months, mustard oil-induced vascular EB leakage in arsenic-fed (20 mg/kg) mice was similar to that in control mice. Dramatic increases in mustard oil-induced vascular leakage were only present in mice systemically exposed to the high arsenic dose, indicating the synergistic effects of the high arsenic dose and mustard oil.

  10. Arsenic removal by nanoparticles: a review.

    Science.gov (United States)

    Habuda-Stanić, Mirna; Nujić, Marija

    2015-06-01

    Contamination of natural waters with arsenic, which is both toxic and carcinogenic, is widespread. Among various technologies that have been employed for arsenic removal from water, such as coagulation, filtration, membrane separation, ion exchange, etc., adsorption offers many advantages including simple and stable operation, easy handling of waste, absence of added reagents, compact facilities, and generally lower operation cost, but the need for technological innovation for water purification is gaining attention worldwide. Nanotechnology is considered to play a crucial role in providing clean and affordable water to meet human demands. This review presents an overview of nanoparticles and nanobased adsorbents and its efficiencies in arsenic removal from water. The paper highlights the application of nanomaterials and their properties, mechanisms, and advantages over conventional adsorbents for arsenic removal from contaminated water.

  11. Arsenic removal in drinking water by reverse osmosis

    OpenAIRE

    Ahmad, Md. Fayej

    2012-01-01

    Arsenic is widely distributed in nature in the air, water and soil. Acute and chronic arsenic exposure by drinking water has been reported in many countries, especially Argentina, Bangladesh, India, Mexico, Mongolia, Thailand and Taiwan. There are many techniques used to remove arsenic from drinking water. Among them reverse osmosis is widely used. Therefore the purpose of this study is to find the conditions favorable for removal of arsenic from drinking water by using reverse osmosis ...

  12. Chronic arsenic exposure increases TGFalpha concentration in bladder urothelial cells of Mexican populations environmentally exposed to inorganic arsenic

    International Nuclear Information System (INIS)

    Valenzuela, Olga L.; Germolec, Dori R.; Borja-Aburto, Victor H.; Contreras-Ruiz, Jose; Garcia-Vargas, Gonzalo G.; Razo, Luz M. del

    2007-01-01

    Inorganic arsenic (iAs) is a well-established carcinogen and human exposure has been associated with a variety of cancers including those of skin, lung, and bladder. High expression of transforming growth factor alpha (TGF-α) has associated with local relapses in early stages of urinary bladder cancer. iAs exposures are at least in part determined by the rate of formation and composition of iAs metabolites (MAs III , MAs V , DMAs III , DMAs V ). This study examines the relationship between TGF-α concentration in exfoliated bladder urothelial cells (BUC) separated from urine and urinary arsenic species in 72 resident women (18-51 years old) from areas exposed to different concentrations of iAs in drinking water (2-378 ppb) in central Mexico. Urinary arsenic species, including trivalent methylated metabolites were measured by hydride generation atomic absorption spectrometry method. The concentration of TGF-α in BUC was measured using an ELISA assay. Results show a statistically significant positive correlation between TGF-α concentration in BUC and each of the six arsenic species present in urine. The multivariate linear regression analyses show that the increment of TGF-α levels in BUC was importantly associated with the presence of arsenic species after adjusting by age, and presence of urinary infection. People from areas with high arsenic exposure had a significantly higher TGF-α concentration in BUC than people from areas of low arsenic exposure (128.8 vs. 64.4 pg/mg protein; p < 0.05). Notably, exfoliated cells isolated from individuals with skin lesions contained significantly greater amount of TGF-α than cells from individuals without skin lesions: 157.7 vs. 64.9 pg/mg protein (p = 0.003). These results suggest that TGF-α in exfoliated BUC may serve as a susceptibility marker of adverse health effects on epithelial tissue in arsenic-endemic areas

  13. Review of arsenic contamination and human exposure through water food in rural areas in Vietnam

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, Celia

    2016-05-01

    . Products like noodles and rice wine were examined as well as local pork and poultry. Vegetables from the gardens and rice plants from the surrounding paddy fields were sampled and analyzed. All plants were found to have accumulated arsenic, leafy vegetables showing the highest arsenic concentrations. The results are discussed and compared, and conclusions are drawn in the last part. The reducing conditions in the paddy fields are likely to have a strong influence on arsenic uptake in rice plants and on transport to the aquifer. The installation of a wastewater treatment plant under the research proJect IN HAND, which was funded by the BMBF German Ministry of Education and Research, led to lower arsenic concentrations in the groundwater. Soaring industrialization, the growing population, and the consumers' changing behavior will widely affect land and water use and hence the potential mobilization of arsenic. In order to mitigate further human exposure to arsenic, wastewater needs to be treated and the reducing conditions in the rice fields need to be decreased by means of enhanced cultivation methods.

  14. Review of arsenic contamination and human exposure through water food in rural areas in Vietnam

    International Nuclear Information System (INIS)

    Hahn, Celia

    2016-01-01

    . Products like noodles and rice wine were examined as well as local pork and poultry. Vegetables from the gardens and rice plants from the surrounding paddy fields were sampled and analyzed. All plants were found to have accumulated arsenic, leafy vegetables showing the highest arsenic concentrations. The results are discussed and compared, and conclusions are drawn in the last part. The reducing conditions in the paddy fields are likely to have a strong influence on arsenic uptake in rice plants and on transport to the aquifer. The installation of a wastewater treatment plant under the research proJect IN HAND, which was funded by the BMBF German Ministry of Education and Research, led to lower arsenic concentrations in the groundwater. Soaring industrialization, the growing population, and the consumers' changing behavior will widely affect land and water use and hence the potential mobilization of arsenic. In order to mitigate further human exposure to arsenic, wastewater needs to be treated and the reducing conditions in the rice fields need to be decreased by means of enhanced cultivation methods.

  15. Distribution of microbial arsenic reduction, oxidation and extrusion genes along a wide range of environmental arsenic concentrations.

    Directory of Open Access Journals (Sweden)

    Lorena V Escudero

    Full Text Available The presence of the arsenic oxidation, reduction, and extrusion genes arsC, arrA, aioA, and acr3 was explored in a range of natural environments in northern Chile, with arsenic concentrations spanning six orders of magnitude. A combination of primers from the literature and newly designed primers were used to explore the presence of the arsC gene, coding for the reduction of As (V to As (III in one of the most common detoxification mechanisms. Enterobacterial related arsC genes appeared only in the environments with the lowest As concentration, while Firmicutes-like genes were present throughout the range of As concentrations. The arrA gene, involved in anaerobic respiration using As (V as electron acceptor, was found in all the systems studied. The As (III oxidation gene aioA and the As (III transport gene acr3 were tracked with two primer sets each and they were also found to be spread through the As concentration gradient. Sediment samples had a higher number of arsenic related genes than water samples. Considering the results of the bacterial community composition available for these samples, the higher microbial phylogenetic diversity of microbes inhabiting the sediments may explain the increased number of genetic resources found to cope with arsenic. Overall, the environmental distribution of arsenic related genes suggests that the occurrence of different ArsC families provides different degrees of protection against arsenic as previously described in laboratory strains, and that the glutaredoxin (Grx-linked arsenate reductases related to Enterobacteria do not confer enough arsenic resistance to live above certain levels of As concentrations.

  16. Study of arsenic accumulation in rice and evaluation of protective effects of Chorchorus olitorius leaves against arsenic contaminated rice induced toxicities in Wistar albino rats.

    Science.gov (United States)

    Hosen, Saeed Mohammed Imran; Das, Dipesh; Kobi, Rupkanowar; Chowdhury, Dil Umme Salma; Alam, Md Jibran; Rudra, Bashudev; Bakar, Muhammad Abu; Islam, Saiful; Rahman, Zillur; Al-Forkan, Mohammad

    2016-10-14

    In the present study, we investigated the arsenic accumulation in different parts of rice irrigated with arsenic contaminated water. Besides, we also evaluated the protective effects of Corchorus olitorius leaves against arsenic contaminated rice induced toxicities in animal model. A pot experiment was conducted with arsenic amended irrigation water (0.0, 25.0, 50.0 and 75.0 mg/L As) to investigate the arsenic accumulation in different parts of rice. In order to evaluate the protective effects of Corchorus olitorius leaves, twenty Wistar albino rats were divided into four different groups. The control group (Group-I) was supplied with normal laboratory pellets while groups II, III, and IV received normal laboratory pellets supplemented with arsenic contaminated rice, C. olitorius leaf powder (4 %), arsenic contaminated rice plus C. olitorius leaf powder (4 %) respectively. Different haematological parameters and serum indices were analyzed to evaluate the protective effects of Corchorus olitorius leaves against arsenic intoxication. To gather more supportive evidences of Corchorus olitorius potentiality against arsenic intoxication, histopathological analysis of liver, kidney, spleen and heart tissues was also performed. From the pot experiment, we have found a significant (p ≤ 0.05) increase of arsenic accumulation in different parts of rice with the increase of arsenic concentrations in irrigation water and the trend of accumulation was found as root > straw > husk > grain. Another part of the experiment revealed that supplementation of C. olitorius leaves with arsenic contaminated rice significantly (p rice induced toxicities. Arsenic accumulation in different parts of rice increased dose-dependently. Hence, for irrigation purpose arsenic contaminated water cannot be used. Furthermore, arsenic contaminated rice induced several toxicities in animal model, most of which could be minimized with the food supplementation of Corchorus olitorius

  17. Slow arsenic poisoning of the contaminated groundwater users

    International Nuclear Information System (INIS)

    Uddin, M. M.; Harun-Ar-Rashid, A. K. M.; Hossain, S. M.; Hafiz, M. A.; Nahar, K.; Mubin, S. H.

    2006-01-01

    This paper gives impact of Arsenic contaminated water on human health as well as overview of the extent and severity of groundwater arsenic contamination in Bangladesh. Scalp hair is the most important part of the human body to monitor the accumulation of this type of poison. Therefore, an experiment has been carried out by Neutron Activation Analysis at Atomic Energy Research Establishment , Savar, Dhaka, Bangladesh on human hair of corresponding tube well water users of these areas to determine the total accumulation of arsenic to their body. Hair samples collected from the region where the groundwater was found highly contaminated with arsenic. The obtained results of arsenic concentration in the lower age (Hb) categories of users (below 12 years of age users) is in the range of 0.33 to 3.29 μg/g (ppm) and that in the Hu categories (upper 12 years of age users) is 0.47 to 6.64 μg/g (ppm). Where as maximum permissible range is 1 ppm certified from WHO. Results show that the peoples are highly affected where the groundwater is highly contaminated with arsenic and acts as the primary source of arsenic poisoning among the peoples of those areas. The results indicate that human population is affected with arsenic locally using the contaminated water for a long time

  18. Phytoremediation of arsenic in submerged soil by wetland plants.

    Science.gov (United States)

    Jomjun, Nateewattana; Siripen, Trichaiyaporn; Maliwan, Saeouy; Jintapat, Nateewattana; Prasak, Thavornyutikarn; Somporn, Choonluchanon; Petch, Pengchai

    2011-01-01

    Wetland aquatic plants including Canna glauca L., Colocasia esculenta L. Schott, Cyperus papyrus L. and Typha angustifolia L. were used in the phytoremediation of submerged soil polluted by arsenic (As). Cyperus papyrus L. was noticed as the largest biomass producer which has arsenic accumulation capacity of 130-172 mg As/kg plant. In terms of arsenic removal rate, however, Colocasia esculenta L. was recognized as the largest and fastest arsenic remover in this study. Its arsenic removal rate was 68 mg As/m2/day while those rates of Canna glauca L., Cyperus papyrus L. and Typha angustifolia L. were 61 mg As/m2/day, 56 mg As/m2/day, and 56 mg As/m2/day, respectively. Although the 4 aquatic plants were inferior in arsenic accumulation, their high arsenic removal rates were observed. Phytostabilization should be probable for the application of these plants.

  19. Association of Low-Moderate Arsenic Exposure and Arsenic Metabolism with Incident Diabetes and Insulin Resistance in the Strong Heart Family Study.

    Science.gov (United States)

    Grau-Perez, Maria; Kuo, Chin-Chi; Gribble, Matthew O; Balakrishnan, Poojitha; Jones Spratlen, Miranda; Vaidya, Dhananjay; Francesconi, Kevin A; Goessler, Walter; Guallar, Eliseo; Silbergeld, Ellen K; Umans, Jason G; Best, Lyle G; Lee, Elisa T; Howard, Barbara V; Cole, Shelley A; Navas-Acien, Ana

    2017-12-20

    High arsenic exposure has been related to diabetes, but at low-moderate levels the evidence is mixed. Arsenic metabolism, which is partly genetically controlled and may rely on certain B vitamins, plays a role in arsenic toxicity. We evaluated the prospective association of arsenic exposure and metabolism with type 2 diabetes and insulin resistance. We included 1,838 American Indian men and women free of diabetes (median age, 36 y). Arsenic exposure was assessed as the sum of inorganic arsenic (iAs), monomethylarsonate (MMA), and dimethylarsinate (DMA) urine concentrations (ΣAs). Arsenic metabolism was evaluated by the proportions of iAs, MMA, and DMA over their sum (iAs%, MMA%, and DMA%). Homeostasis model assessment for insulin resistance (HOMA2-IR) was measured at baseline and follow-up visits. Incident diabetes was evaluated at follow-up. Median ΣAs, iAs%, MMA%, and DMA% was 4.4 μg/g creatinine, 9.5%, 14.4%, and 75.6%, respectively. Over 10,327 person-years of follow-up, 252 participants developed diabetes. Median HOMA2-IR at baseline was 1.5. The fully adjusted hazard ratio [95% confidence interval (CI)] for incident diabetes per an interquartile range increase in ΣAs was 1.57 (95% CI: 1.18, 2.08) in participants without prediabetes at baseline. Arsenic metabolism was not associated with incident diabetes. ΣAs was positively associated with HOMA2-IR at baseline but negatively with HOMA2-IR at follow-up. Increased MMA% was associated with lower HOMA2-IR when either iAs% or DMA% decreased. The association of arsenic metabolism with HOMA2-IR differed by B-vitamin intake and AS3MT genetics variants. Among participants without baseline prediabetes, arsenic exposure was associated with incident diabetes. Low MMA% was cross-sectional and prospectively associated with higher HOMA2-IR. Research is needed to confirm possible interactions of arsenic metabolism with B vitamins and AS3MT variants on diabetes risk. https://doi.org/10.1289/EHP2566.

  20. Use of arsenic-73 in research supports USEPA's regulatory decisions on inorganic arsenic in drinking water*

    Science.gov (United States)

    Inorganic arsenic is a natural contaminant of drinking water in the United States and throughout the world. Long term exposure to inorganic arsenic in drinking water at elevated levels (>100 ug/L) is associated with development of cancer in several organs, cardiovascular disease,...

  1. Bacteria-mediated arsenic oxidation and reduction in the growth media of arsenic hyperaccumulator Pteris vittata.

    Science.gov (United States)

    Wang, Xin; Rathinasabapathi, Bala; de Oliveira, Letuzia Maria; Guilherme, Luiz R G; Ma, Lena Q

    2012-10-16

    Microbes play an important role in arsenic transformation and cycling in the environment. Microbial arsenic oxidation and reduction were demonstrated in the growth media of arsenic hyperaccumulator Pteris vittata L. All arsenite (AsIII) at 0.1 mM in the media was oxidized after 48 h incubation. Oxidation was largely inhibited by antibiotics, indicating that bacteria played a dominant role. To identify AsIII oxidizing bacteria, degenerate primers were used to amplify ∼500 bp of the AsIII oxidase gene aioA (aroA) using DNA extracted from the media. One aioA (aroA)-like sequence (MG-1, tentatively identified as Acinetobacter sp.) was amplified, exhibiting 82% and 91% identity in terms of gene and deduced protein sequence to those from Acinetobacter sp. 33. In addition, four bacterial strains with different arsenic tolerance were isolated and identified as Comamonas sp.C-1, Flavobacterium sp. C-2, Staphylococcus sp. C-3, and Pseudomonas sp. C-4 using carbon utilization, fatty acid profiles, and/or sequencing 16s rRNA gene. These isolates exhibited dual capacity for both AsV reduction and AsIII oxidation under ambient conditions. Arsenic-resistant bacteria with strong AsIII oxidizing ability may have potential to improve bioremediation of AsIII-contaminated water using P. vittata and/or other biochemical strategies.

  2. [Effect of glutathione and sodium selenite on the metabolism of arsenic in mice exposed to arsenic through drinking water].

    Science.gov (United States)

    Yu, Xiao-Yun; Zhong, Yuan; Niu, Yu-Hong; Qu, Chun-Qing; Li, Ge-Xin; Lü, Xiu-Qiang; Sun, Gui-Fan; Jin, Ya-Ping

    2008-09-01

    To explore the effect of glutathione (GSH) and sodium selenite on the metabolism of arsenic in the liver, kidney and blood of mice exposed to iAsIII through drinking water. The mice were randomly divided into control, arsenic, GSH and sodium selenite group, respectively. And each group had eight mice and the mice were exposed to 50 mg/L arsenite by drinking water for 4 weeks. Mice were intraperitoneally injected with GSH (600 mg/kg) and sodium selenite (1 mg/kg) for seven days from the beginning of the fourth week. At the end of the fourth week, liver, kidney and blood were sampled to assess the concentrations of inorganic arsenic (iAs), monomethylarsenic acid (MMA), dimethylarsenic acid (DMA) by hydride generation trapping by ultra-hypothermia coupled with atomic absorption spectrometry. The liver DMA (233.76 +/- 60.63 ng/g) concentration in GSH group was significantly higher than the arsenic group (218.36 +/- 42.71 ng/g). The concentration of DMA (88.52 +/- 30.86 ng/g) and total arsenic (TAs) (162.32 +/- 49.45 ng/g) in blood of GSH group was significantly higher than those [(45.32 +/- 12.19 ng/g), (108.51 +/- 18.00 ng/g), respectively] of arsenic groups(q values were 3.06, 6.40, 10.72 respectively, P < 0.05). The primary methylated index (PMI) (0.65 +/- 0.050) and secondary methylated index (SMI) (0.55 +/- 0.050) in liver sample of GSH group were significantly higher than those (0.58 +/- 0.056, 0.44 +/- 0. 093) in arsenic group. In blood samples, the PMI (0.85 +/- 0.066) in GSH group was significantly higher than that (0.54 +/- 0.113) in arsenic group (q values were 3.75, 5.26, 4.21 respectively, P < 0.05). However, no significant difference was identified between sodium selenite and arsenic groups in liver, kidney or blood samples. And no significant difference was detected in kidney samples among all arsenic exposing groups. Exogenous GSH could promote the methylated metabolism of iAsIII, but sodium selenite showed no significant effects.

  3. Reduction of arsenite-enhanced ultraviolet radiation-induced DNA damage by supplemental zinc

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Karen L.; King, Brenee S.; Sandoval, Monica M.; Liu, Ke Jian; Hudson, Laurie G., E-mail: lhudson@salud.unm.edu

    2013-06-01

    Arsenic is a recognized human carcinogen and there is evidence that arsenic augments the carcinogenicity of DNA damaging agents such as ultraviolet radiation (UVR) thereby acting as a co-carcinogen. Inhibition of DNA repair is one proposed mechanism to account for the co-carcinogenic actions of arsenic. We and others find that arsenite interferes with the function of certain zinc finger DNA repair proteins. Furthermore, we reported that zinc reverses the effects of arsenite in cultured cells and a DNA repair target protein, poly (ADP-ribose) polymerase-1. In order to determine whether zinc ameliorates the effects of arsenite on UVR-induced DNA damage in human keratinocytes and in an in vivo model, normal human epidermal keratinocytes and SKH-1 hairless mice were exposed to arsenite, zinc or both before solar-simulated (ss) UVR exposure. Poly (ADP-ribose) polymerase activity, DNA damage and mutation frequencies at the Hprt locus were measured in each treatment group in normal human keratinocytes. DNA damage was assessed in vivo by immunohistochemical staining of skin sections isolated from SKH-1 hairless mice. Cell-based findings demonstrate that ssUVR-induced DNA damage and mutagenesis are enhanced by arsenite, and supplemental zinc partially reverses the arsenite effect. In vivo studies confirm that zinc supplementation decreases arsenite-enhanced DNA damage in response to ssUVR exposure. From these data we can conclude that zinc offsets the impact of arsenic on ssUVR-stimulated DNA damage in cells and in vivo suggesting that zinc supplementation may provide a strategy to improve DNA repair capacity in arsenic exposed human populations. - Highlights: • Low levels of arsenite enhance UV-induced DNA damage in human keratinocytes. • UV-initiated HPRT mutation frequency is enhanced by arsenite. • Zinc supplementation offsets DNA damage and mutation frequency enhanced by arsenite. • Zinc-dependent reduction of arsenite enhanced DNA damage is confirmed in vivo.

  4. Construction of a modular arsenic resistance operon in E. coli and the production of arsenic nanoparticles

    Directory of Open Access Journals (Sweden)

    Matthew Charles Edmundson

    2015-10-01

    Full Text Available Arsenic is a widespread contaminant of both land and water around the world. Current methods of decontamination such as phytoremediation and chemical adsorbents can be resource and time intensive, and may not be suitable for some areas such as remote communities where cost and transportation are major issues. Bacterial decontamination, with strict controls preventing environmental release, may offer a cost-effective alternative or provide a financial incentive when used in combination with other remediation techniques. In this study we have produced E. coli strains containing arsenic resistance genes from a number of sources, overexpressing them and testing their effects on arsenic resistance. While the lab E. coli strain JM109 (the wild-type is resistant up to 20 mM sodium arsenate the strain containing our plasmid pEC20 is resistant up to 80 mM. When combined with our construct pArsRBCC arsenic-containing nanoparticles were observed at the cell surface; the elements of pEC20 and pArsRBCC were therefore combined in a modular construct, pArs, in order to evaluate the roles and synergistic effects of the components of the original plasmids in arsenic resistance and nanoparticle formation. We also investigated the use of introducing the lac operator in order to more tightly control expression from pArs. We demonstrate that our strains are able to reduce toxic forms of arsenic into stable, insoluble metallic As(0, providing one way to remove arsenate contamination, and which may also be of benefit for other heavy metals.

  5. Aquatic arsenic: phytoremediation using floating macrophytes.

    Science.gov (United States)

    Rahman, M Azizur; Hasegawa, H

    2011-04-01

    Phytoremediation, a plant based green technology, has received increasing attention after the discovery of hyperaccumulating plants which are able to accumulate, translocate, and concentrate high amount of certain toxic elements in their above-ground/harvestable parts. Phytoremediation includes several processes namely, phytoextraction, phytodegradation, rhizofiltration, phytostabilization and phytovolatilization. Both terrestrial and aquatic plants have been tested to remediate contaminated soils and waters, respectively. A number of aquatic plant species have been investigated for the remediation of toxic contaminants such as As, Zn, Cd, Cu, Pb, Cr, Hg, etc. Arsenic, one of the deadly toxic elements, is widely distributed in the aquatic systems as a result of mineral dissolution from volcanic or sedimentary rocks as well as from the dilution of geothermal waters. In addition, the agricultural and industrial effluent discharges are also considered for arsenic contamination in natural waters. Some aquatic plants have been reported to accumulate high level of arsenic from contaminated water. Water hyacinth (Eichhornia crassipes), duckweeds (Lemna gibba, Lemna minor, Spirodela polyrhiza), water spinach (Ipomoea aquatica), water ferns (Azolla caroliniana, Azolla filiculoides, and Azolla pinnata), water cabbage (Pistia stratiotes), hydrilla (Hydrilla verticillata) and watercress (Lepidium sativum) have been studied to investigate their arsenic uptake ability and mechanisms, and to evaluate their potential in phytoremediation technology. It has been suggested that the aquatic macrophytes would be potential for arsenic phytoremediation, and this paper reviews up to date knowledge on arsenic phytoremediation by common aquatic macrophytes. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Relationship between arsenic skin lesions and the age of natural menopause.

    Science.gov (United States)

    Yunus, Fakir Md; Rahman, Musarrat Jabeen; Alam, Md Zahidul; Hore, Samar Kumar; Rahman, Mahfuzar

    2014-05-02

    Chronic exposure to arsenic is associated with neoplastic, cardiovascular, endocrine, neuro-developmental disorders and can have an adverse effect on women's reproductive health outcomes. This study examined the relationship between arsenic skin lesions (a hallmark sign of chronic arsenic poisoning) and age of natural menopause (final menopausal period) in populations with high levels of arsenic exposure in Bangladesh. We compared menopausal age in two groups of women--with and without arsenic skin lesions; and presence of arsenic skin lesions was used as an indicator for chronic arsenic exposure. In a cross-sectional study, a total of 210 participants were randomly identified from two ongoing studies--participants with arsenic skin lesions were identified from an ongoing clinical trial and participants with no arsenic skin lesions were identified from an ongoing cohort study. Mean age of menopause between these two groups were calculated and compared. Multivariable linear regression was used to estimate the relationship between the status of the arsenic skin lesions and age of natural menopause in women. Women with arsenic skin lesions were 1.5 years younger (p <0.001) at the time of menopause compared to those without arsenic skin lesions. After adjusting with contraceptive use, body mass index, urinary arsenic level and family history of premature menopause, the difference between the groups' age at menopause was 2.1 years earlier (p <0.001) for respondents with arsenic skin lesions. The study showed a statistically significant association between chronic exposure to arsenic and age at menopause. Heavily exposed women experienced menopause two years earlier than those with lower or no exposure.

  7. Tolerance of Mycorrhiza infected pistachio (Pistacia vera L.) seedling to drought stress under glasshouse conditions.

    Science.gov (United States)

    Abbaspour, H; Saeidi-Sar, S; Afshari, H; Abdel-Wahhab, M A

    2012-05-01

    The influence of Glomus etunicatum colonization on plant growth and drought tolerance of 3-month-old Pistacia vera seedlings in potted culture was studied in two different water treatments. The arbuscular mycorrhiza (AM) inoculation and plant growth (including plant shoot and root weight, leaf area, and total chlorophyll) were higher for well-watered than for water-stressed plants. The growth of AM-treated seedlings was higher than non-AM-treatment regardless of water status. P, K, Zn and Cu contents in AM-treated shoots were greater than those in non-AM shoots under well-watered conditions and drought stress. N and Ca content were higher under drought stress, while AM symbiosis did not affect the Mg content. The contents of soluble sugars, proteins, flavonoid and proline were higher in mycorrhizal than non-mycorrhizal-treated plants under the whole water regime. AM colonization increased the activities of peroxidase enzyme in treatments, but did not affect the catalase activity in shoots and roots under well-watered conditions and drought stress. We conclude that AM colonization improved the drought tolerance of P. vera seedlings by increasing the accumulation of osmotic adjustment compounds, nutritional and antioxidant enzyme activity. It appears that AM formation enhanced the drought tolerance of pistachio plants, which increased host biomass and plant growth. Copyright © 2012 Elsevier GmbH. All rights reserved.

  8. An insight of environmental contamination of arsenic on animal health

    Directory of Open Access Journals (Sweden)

    Paramita Mandal

    2017-03-01

    Full Text Available The main threats to human health from heavy metals are associated with exposure to lead, cadmium, mercury and arsenic. Exposure to arsenic is mainly via intake of food and drinking water, food being the most important source in most populations. Although adverse health effects of heavy metals have been known for a long time, exposure to heavy metals continues and is even increasing in some areas. Long-term exposure to arsenic in drinking-water is mainly related to increased risks of skin cancer, but also some other cancers, as well as other skin lesions such as hyperkeratosis and pigmentation changes. Therefore, measures should be taken to reduce arsenic exposure in the general population in order to minimize the risk of adverse health effects. Animal are being exposed to arsenic through contaminated drinking water, feedstuff, grasses, vegetables and different leaves. Arsenic has been the most common causes of inorganic chemical poisoning in farm animals. Although, sub-chronic and chronic exposure of arsenic do not generally reveal external signs or symptoms in farm animals but arsenic (or metabolites concentrations in blood, hair, hoofs and urine are remained high in animals of arsenic contaminated zones. So it is assumed that concentration of arsenic in blood, urine, hair or milk have been used as biomarkers of arsenic exposure in field animals.

  9. Nitrogen and carbon/nitrogen dynamics in arbuscular mycorrhiza: the great unknown.

    Science.gov (United States)

    Corrêa, A; Cruz, C; Ferrol, N

    2015-10-01

    Many studies have established that arbuscular mycorrhizal fungi transfer N to the host plant. However, the role and importance of arbuscular mycorrhiza (AM) in plant N nutrition is still uncertain, as are the C/N interactions within the symbiosis. Published reports provide differing, and often contradictory, results that are difficult to combine in a coherent framework. This review explores questions such as: What makes the difference between a positive and a negative effect of AM on plant N nutrition? Is the mycorrhizal N response (MNR) correlated to the mycorrhizal growth response (MGR), and how or under which conditions? Is the MNR effect on plant growth C mediated? Is plant C investment on fungal growth related to N needs or N benefit? How is the N for C trade between symbionts regulated? The patternless nature of current knowledge is made evident, and possible reasons for this are discussed.

  10. Method development for arsenic analysis by modification in spectrophotometric technique

    Directory of Open Access Journals (Sweden)

    M. A. Tahir

    2012-01-01

    Full Text Available Arsenic is a non-metallic constituent, present naturally in groundwater due to some minerals and rocks. Arsenic is not geologically uncommon and occurs in natural water as arsenate and arsenite. Additionally, arsenic may occur from industrial discharges or insecticide application. World Health Organization (WHO and Pakistan Standard Quality Control Authority have recommended a permissible limit of 10 ppb for arsenic in drinking water. Arsenic at lower concentrations can be determined in water by using high tech instruments like the Atomic Absorption Spectrometer (hydride generation. Because arsenic concentration at low limits of 1 ppb can not be determined easily with simple spectrophotometric technique, the spectrophotometric technique using silver diethyldithiocarbamate was modified to achieve better results, up to the extent of 1 ppb arsenic concentration.

  11. Reduction and Coordination of Arsenic in Indian Mustard1

    Science.gov (United States)

    Pickering, Ingrid J.; Prince, Roger C.; George, Martin J.; Smith, Robert D.; George, Graham N.; Salt, David E.

    2000-01-01

    The bioaccumulation of arsenic by plants may provide a means of removing this element from contaminated soils and waters. However, to optimize this process it is important to understand the biological mechanisms involved. Using a combination of techniques, including x-ray absorption spectroscopy, we have established the biochemical fate of arsenic taken up by Indian mustard (Brassica juncea). After arsenate uptake by the roots, possibly via the phosphate transport mechanism, a small fraction is exported to the shoot via the xylem as the oxyanions arsenate and arsenite. Once in the shoot, the arsenic is stored as an AsIII-tris-thiolate complex. The majority of the arsenic remains in the roots as an AsIII-tris-thiolate complex, which is indistinguishable from that found in the shoots and from AsIII-tris-glutathione. The thiolate donors are thus probably either glutathione or phytochelatins. The addition of the dithiol arsenic chelator dimercaptosuccinate to the hydroponic culture medium caused a 5-fold-increased arsenic level in the leaves, although the total arsenic accumulation was only marginally increased. This suggests that the addition of dimercaptosuccinate to arsenic-contaminated soils may provide a way to promote arsenic bioaccumulation in plant shoots, a process that will be essential for the development of an efficient phytoremediation strategy for this element. PMID:10759512

  12. Ecotoxicology of arsenic in the marine environment

    Energy Technology Data Exchange (ETDEWEB)

    Neff, J.M. [Battelle Ocean Sciences Lab., Duxbury, MA (United States)

    1997-05-01

    Arsenic has a complex marine biogeochemistry that has important implications for its toxicity to marine organisms and their consumers. The average concentration of total arsenic in the ocean is about 1.7 {micro}g/L, about two orders of magnitude higher than the US Environmental Protection Agency`s human health criterion value of 0.0175 {micro}g/L. The dominant form of arsenic in oxygenated marine and brackish waters in arsenate (As V). The more toxic and potentially carcinogenic arsenite (As III) rarely accounts for more than 20% of total arsenic in seawater. Uncontaminated marine sediments contain from 5 to about 40 {micro}g/g dry weight total arsenic. Arsenate dominates in oxidized sediments and is associated primarily with iron oxyhydroxides. In reducing marine sediments, arsenate is reduced to arsenite and is associated primarily with sulfide minerals. Marine algae accumulate arsenate from seawater, reduce it to arsenite, and then oxidize the arsenite to a large number of organoarsenic compounds. The algae release arsenite, methylarsonic acid, and dimethylarsinic acid to seawater. Dissolved arsenite and arsenate are more toxic to marine phytoplankton than to marine invertebrates and fish. This may be due to the fact that marine animals have a limited ability to bioconcentrate inorganic arsenic from seawater but can bioaccumulate organoarsenic compounds from their food. Tissues of marine invertebrates and fish contain high concentrations of arsenic, usually in the range of about 1 to 100 {micro}g/g dry weight, most of it in the form of organoarsenic compounds, particularly arsenobetaine. Organoarsenic compounds are bioaccumulated by human consumers of seafood products, but the arsenic is excreted rapidly, mostly as organoarsenic compounds. Arsenobetaine, the most abundant organoarsenic compound in seafoods, is not toxic or carcinogenic to mammals. Little of the organoarsenic accumulated by humans from seafood is converted to toxic inorganic arsenite.

  13. Total arsenic in selected food samples from Argentina: Estimation of their contribution to inorganic arsenic dietary intake.

    Science.gov (United States)

    Sigrist, Mirna; Hilbe, Nandi; Brusa, Lucila; Campagnoli, Darío; Beldoménico, Horacio

    2016-11-01

    An optimized flow injection hydride generation atomic absorption spectroscopy (FI-HGAAS) method was used to determine total arsenic in selected food samples (beef, chicken, fish, milk, cheese, egg, rice, rice-based products, wheat flour, corn flour, oats, breakfast cereals, legumes and potatoes) and to estimate their contributions to inorganic arsenic dietary intake. The limit of detection (LOD) and limit of quantification (LOQ) values obtained were 6μgkg(-)(1) and 18μgkg(-)(1), respectively. The mean recovery range obtained for all food at a fortification level of 200μgkg(-)(1) was 85-110%. Accuracy was evaluated using dogfish liver certified reference material (DOLT-3 NRC) for trace metals. The highest total arsenic concentrations (in μgkg(-)(1)) were found in fish (152-439), rice (87-316) and rice-based products (52-201). The contribution to inorganic arsenic (i-As) intake was calculated from the mean i-As content of each food (calculated by applying conversion factors to total arsenic data) and the mean consumption per day. The primary contributors to inorganic arsenic intake were wheat flour, including its proportion in wheat flour-based products (breads, pasta and cookies), followed by rice; both foods account for close to 53% and 17% of the intake, respectively. The i-As dietary intake, estimated as 10.7μgday(-)(1), was significantly lower than that from drinking water in vast regions of Argentina. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Diverse arsenic- and iron-cycling microbial communities in arsenic-contaminated aquifers used for drinking water in Bangladesh.

    Science.gov (United States)

    Hassan, Zahid; Sultana, Munawar; van Breukelen, Boris M; Khan, Sirajul I; Röling, Wilfred F M

    2015-04-01

    Subsurface removal of arsenic by injection with oxygenated groundwater has been proposed as a viable technology for obtaining 'safe' drinking water in Bangladesh. While the oxidation of ferrous iron to solid ferric iron minerals, to which arsenic adsorbs, is assumed to be driven by abiotic reactions, metal-cycling microorganisms may potentially affect arsenic removal. A cultivation-independent survey covering 24 drinking water wells in several geographical regions in Bangladesh was conducted to obtain information on microbial community structure and diversity in general, and on specific functional groups capable of the oxidation or reduction of arsenic or iron. Each functional group, targeted by either group-specific 16S rRNA or functional gene amplification, occurred in at least 79% of investigated samples. Putative arsenate reducers and iron-oxidizing Gallionellaceae were present at low diversity, while more variation in potentially arsenite-oxidizing microorganisms and iron-reducing Desulfuromonadales was revealed within and between samples. Relations between community composition on the one hand and hydrochemistry on the other hand were in general not evident, apart from an impact of salinity on iron-cycling microorganisms. Our data suggest widespread potential for a positive contribution of arsenite and iron oxidizers to arsenic removal upon injection with oxygenated water, but also indicate a potential risk for arsenic re-mobilization by anaerobic arsenate and iron reducers once injection is halted. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Modulatory role of dietary Chlorella vulgaris powder against arsenic-induced immunotoxicity and oxidative stress in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Zahran, Eman; Risha, Engy

    2014-12-01

    Arsenic intoxicant have long been regarded as an impending carcinogenic, genotoxic, and immunotoxic heavy metal to human and animals as well. In this respect, we evaluated biomarkers of the innate immune response and oxidative stress metabolism in gills and liver of Nile tilapia (Oreochromis niloticus) after arsenic exposure, and the protective role of Chlorella vulgaris (Ch) dietary supplementation were elucidated. Protective role of C. vulgaris (Ch), as supplementary feeds (5% and 10% of the diet) was studied in Nile tilapia (O. niloticus) against arsenic induced toxicity (NaAsO2 at 7 ppm) for 21 days exposure period. A significant down-regulation in innate immune response; including, respiratory burst, lysozyme, and bactericidal activity followed due to deliberately As(+3) exposure. Similarly, oxidative stress response; like nitric oxide (NO), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx), malondialdehyde (MDA) and hydrogen peroxide (H2O2) levels were significantly decreased. Combined treatment of Ch and As(+3) significantly enhanced the innate immune response and antioxidant activity. Strikingly, Ch supplementation at 10% has been considered the optimum for Nile tilapia since it exhibited enhancement of innate immune response and antioxidant activity over the level 5%, and even better than that of control level. Thus, our results concluded that dietary Ch supplementation could protect Nile tilapia against arsenic induced immunosuppression and oxidative stresses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. The Association of Arsenic Exposure and Arsenic Metabolism with the Metabolic Syndrome and its Individual Components: Prospective Evidence from the Strong Heart Family Study.

    Science.gov (United States)

    Spratlen, Miranda J; Grau-Perez, Maria; Best, Lyle G; Yracheta, Joseph; Lazo, Mariana; Vaidya, Dhananjay; Balakrishnan, Poojitha; Gamble, Mary V; Francesconi, Kevin A; Goessler, Walter; Cole, Shelley A; Umans, Jason G; Howard, Barbara V; Navas-Acien, Ana

    2018-03-15

    Inorganic arsenic exposure is ubiquitous and both exposure and inter-individual differences in its metabolism have been associated with cardiometabolic risk. The association between arsenic exposure and arsenic metabolism with metabolic syndrome and its individual components, however, is relatively unknown. We used poisson regression with robust variance to evaluate the association between baseline arsenic exposure (urine arsenic levels) and metabolism (relative percentage of arsenic species over their sum) with incident metabolic syndrome and its individual components (elevated waist circumference, elevated triglycerides, reduced HDL, hypertension, elevated fasting plasma glucose) in 1,047 participants from the Strong Heart Family Study, a prospective family-based cohort in American Indian communities (baseline visits in 1998-1999 and 2001-2003, follow-up visits in 2001-2003 and 2006-2009). 32% of participants developed metabolic syndrome over follow-up. An IQR increase in arsenic exposure was associated with 1.19 (95% CI: 1.01, 1.41) greater risk for elevated fasting plasma glucose but not with other individual components or overall metabolic syndrome. Arsenic metabolism, specifically lower MMA% and higher DMA% was associated with higher risk of overall metabolic syndrome and elevated waist circumference, but not with any other component. These findings support there is a contrasting and independent association between arsenic exposure and arsenic metabolism with metabolic outcomes which may contribute to overall diabetes risk.

  17. Arsenic bioleaching in medical realgar ore and arsenicbearing ...

    African Journals Online (AJOL)

    However, the maximum arsenic leaching ratio from realgar in the presence of mixed unadapted strains was only 12.4 %. Besides, maximum arsenic leaching ratios from arsenic-bearing refractory gold ore by mixed adapted strains or unadapted strains were 45.0 and 22.9 %, respectively. Oxidation of these two ores by ...

  18. Arsenic inhibits hedgehog signaling during P19 cell differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jui Tung [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Bain, Lisa J., E-mail: lbain@clemson.edu [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States)

    2014-12-15

    Arsenic is a toxicant found in ground water around the world, and human exposure mainly comes from drinking water or from crops grown in areas containing arsenic in soils or water. Epidemiological studies have shown that arsenic exposure during development decreased intellectual function, reduced birth weight, and altered locomotor activity, while in vitro studies have shown that arsenite decreased muscle and neuronal cell differentiation. The sonic hedgehog (Shh) signaling pathway plays an important role during the differentiation of both neurons and skeletal muscle. The purpose of this study was to investigate whether arsenic can disrupt Shh signaling in P19 mouse embryonic stem cells, leading to changes muscle and neuronal cell differentiation. P19 embryonic stem cells were exposed to 0, 0.25, or 0.5 μM of sodium arsenite for up to 9 days during cell differentiation. We found that arsenite exposure significantly reduced transcript levels of genes in the Shh pathway in both a time and dose-dependent manner. This included the Shh ligand, which was decreased 2- to 3-fold, the Gli2 transcription factor, which was decreased 2- to 3-fold, and its downstream target gene Ascl1, which was decreased 5-fold. GLI2 protein levels and transcriptional activity were also reduced. However, arsenic did not alter GLI2 primary cilium accumulation or nuclear translocation. Moreover, additional extracellular SHH rescued the inhibitory effects of arsenic on cellular differentiation due to an increase in GLI binding activity. Taken together, we conclude that arsenic exposure affected Shh signaling, ultimately decreasing the expression of the Gli2 transcription factor. These results suggest a mechanism by which arsenic disrupts cell differentiation. - Highlights: • Arsenic exposure decreases sonic hedgehog pathway-related gene expression. • Arsenic decreases GLI2 protein levels and transcriptional activity in P19 cells. • Arsenic exposure does not alter the levels of SHH

  19. Identification of Arsenic Direct-Binding Proteins in Acute Promyelocytic Leukaemia Cells

    Directory of Open Access Journals (Sweden)

    Tao Zhang

    2015-11-01

    Full Text Available The identification of arsenic direct-binding proteins is essential for determining the mechanism by which arsenic trioxide achieves its chemotherapeutic effects. At least two cysteines close together in the amino acid sequence are crucial to the binding of arsenic and essential to the identification of arsenic-binding proteins. In the present study, arsenic binding proteins were pulled down with streptavidin and identified using a liquid chromatograph-mass spectrometer (LC-MS/MS. More than 40 arsenic-binding proteins were separated, and redox-related proteins, glutathione S-transferase P1 (GSTP1, heat shock 70 kDa protein 9 (HSPA9 and pyruvate kinase M2 (PKM2, were further studied using binding assays in vitro. Notably, PKM2 has a high affinity for arsenic. In contrast to PKM2, GSTP1and HSPA9 did not combine with arsenic directly in vitro. These observations suggest that arsenic-mediated acute promyelocytic leukaemia (APL suppressive effects involve PKM2. In summary, we identified several arsenic binding proteins in APL cells and investigated the therapeutic mechanisms of arsenic trioxide for APL. Further investigation into specific signal pathways by which PKM2 mediates APL developments may lead to a better understanding of arsenic effects on APL.

  20. Rapid biotransformation of arsenic by a model protozoan Tetrahymena thermophila

    Energy Technology Data Exchange (ETDEWEB)

    Yin Xixiang [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); State Key Lab of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Zhang Yongyu; Yang Jun [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Zhu Yongguan, E-mail: ygzhu@rcees.ac.cn [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); State Key Lab of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China)

    2011-04-15

    Arsenic biomethylation and biovolatilization are thought to be two important metabolic pathways in aquatic and soil environments. Tetrahymena thermophila is a genus of free-living ciliated protozoan that is widely distributed in freshwater environments around the world. In this study, we studied arsenic accumulation, speciation, efflux, methylation and volatilization in this unicellular eukaryote exposed to various concentrations of arsenate. Our results show that T. thermophila accumulated 187 mg.kg{sup -1} dry weight of arsenic when exposed to 40 {mu}M for 48 h, with MMAs(V) (monomethylarsenate) and DMAs(V) (dimethylarsenate) as the dominant species, accounting for 66% of the total arsenic. Meanwhile, arsenate, arsenite, MMAs(V) and DMAs(V) were detected in the culture medium; the last three were released by the cells. The production of volatile arsenic increased with increasing external As(V) concentrations and exposure time. To our knowledge, this is the first study on arsenic metabolism, particularly biomethylation and biovolatilization, in protozoa. - Tetrahymena thermophila can rapidly methylate arsenic, and produce volatile arsenicals.

  1. Alternative technology for arsenic removal from drinking water

    Directory of Open Access Journals (Sweden)

    Purenović Milovan

    2007-01-01

    Full Text Available Arsenic is a naturally occurring element in water, food and air. It is known as a poison, but in very small quantities it is showed to be an essential element. Actual problem in the world is arsenic removal from drinking water using modern and alternative technology, especially because EPA's and other international standards have reduced MCL from 50 to 10 ug/1. Because of rivers and lakes pollution, in a number of plants for natural water purification, average concentrations of arsenic in water are up to 100 ug/1. According to MCL, present technologies are unadjusted for safely arsenic removal for concentrations below of 10 ug/1. This fact has inspired many companies to solve this problem adequately, by using an alternative technologies and new process able materials. In this paper the observation of conventional and the alternative technologies will be given, bearing in mind complex chemistry and electrochemistry of arsenic, formation of colloidal arsenic, which causes the biggest problems in water purification technologies. In this paper many results will be presented, which are obtained using the alternative technologies, as well as the newest results of original author's investigations. Using new nanomaterials, on Pilot plant "VALETA H2O-92", concentration of arsenic was removed far below MLC value.

  2. Poisoning by coal smoke containing arsenic and fluoride

    Energy Technology Data Exchange (ETDEWEB)

    An, D.; He, Y.G.; Hu, Q.X. [Guizhou Sanitary and Epidemiological Station, Guiyang (China)

    1997-02-01

    An investigation was made into a disease involving skin pigmentation, keratosis of the hands and feet, dental discoloration, and generalized bone and joint pain, stiffness and rigidity, in the village of Bazhi, Zhijin County, Ghizhou Province, People`s Republic of China. Measurements were made of the arsenic and fluoride levels of coal, water, air, food, urine and hair in Bazhi and a control village, Xinzhai, in which coal with a low arsenic content was used. Up to 188 people, including children, in Bazhi and 752 in Xinzhai, were examined for the presence of chronic arsenium, skeletal fluorosis, dental fluorosis and electrocardiogram abnormalities. The coal in Bazhi was found to contain high levels of arsenic and fluoride resulting, after burning in homes without an adequate chimney systems, in pollution of air and food with arsenic and fluoride. The coal in Xinzhai did not cause arsenic pollution but did produce a higher level of fluoride pollution. It was concluded that the endemic disease in Bazhi was caused by pollution by coal smoke containing arsenic and fluoride. It is suggested that arsenic may act synergistically with fluoride so that a lower level of fluoride may produce fluoride toxicity with dental and skeletal fluorosis.

  3. Removal of Arsenic with Oyster Shell: Experimental Measurements

    Directory of Open Access Journals (Sweden)

    Md. Atiqur Rahman, , and

    2008-12-01

    Full Text Available Oyster shell has tremendous potential as a remediation material for the removal of arsenic from groundwater. A single arsenic removal system was developed with oyster shell for tube well water containing arsenic. The system removes arsenic from water by adsorption through fine oyster shell. Various conditions that affect the adsorption/desorption of arsenic were investigated. Adsorption column methods showed the removal of As(III under the following conditions: initial As concentration, 100 µg /L; oyster shell amount, 6 g; particle size, <355µm ; treatment flow rate, 1.7 mL/min; and pH 6.5. Arsenic concentration of the treated water were below the Bangladesh drinking water standard of 50 µg/L for As. The desorption efficiencies with 2M of KOH after the treatment of groundwater were in the range of 80-83%. A combination of techniques was used to measure the pH, conductivity, cations and anions. The average concentrations of other inorganic constituents of health concern (Na, K, Ca, Mg and Fe in treated water were below their respective WHO guideline for drinking. The present study might provide new avenues to achieve the arsenic concentrations required for drinking water recommended by Bangladesh and the World Health Organization (WHO.

  4. Removal of Arsenic from Drinking Water by Adsorption and Coagulation

    Science.gov (United States)

    Zhang, M.; Sugita, H.; Hara, J.; Takahashi, S.

    2013-12-01

    Removal of arsenic from drinking water has been an important issue worldwide, which has attracted greater attentions in recent years especially for supplying safe drinking water in developing countries. Although many kinds of treatment approaches that are available or applicable both in principle and practice, such as adsorption, coagulation, membrane filtration, ion exchange, biological process, electrocoagulation and so on, the first 2 approaches (i.e., adsorption and coagulation) are most promising due to the low-cost, high-efficiency, simplicity of treating systems, and thus can be practically used in developing countries. In this study, a literature survey on water quality in Bangladesh was performed to understand the ranges of arsenic concentration and pH of groundwater in Bangladesh. A series of tests were then organized and performed to investigate the effects of arsenic concentration, arsenic forms, pH, chemical compositions of the materials used for adsorption and coagulation, particle size distribution and treatment time on quality of treated water. The experimental results obtained in the study illustrated that both adsorption and coagulation can be used to effectively reduce the concentrations of either arsenic (V) or arsenic (III) from the contaminated water. Coagulation of arsenic with a magnesium-based material developed in this study can be very effective to remove arsenic, especially arsenic (V), from contaminated water with a concentration of 10 ppm to an undetectable level of 0.002 ppm by ICP analyses. Compared to arsenic (III), arsenic (V) is easier to be removed. The materials used for adsorption and coagulation in this study can remove arsenic (V) up to 9 mg/g and 6 mg/g, and arsenic (III) up to 4 mg/g and 3 mg/g, respectively, depending on test conditions and compositions of the materials being used. The control of pH during treatment can be a challenging technical issue for developing both adsorbent and coagulant. Keywords: Water Treatment

  5. Total and inorganic arsenic in fish samples from Norwegian waters.

    Science.gov (United States)

    Julshamn, Kaare; Nilsen, Bente M; Frantzen, Sylvia; Valdersnes, Stig; Maage, Amund; Nedreaas, Kjell; Sloth, Jens J

    2012-01-01

    The contents of total arsenic and inorganic arsenic were determined in fillet samples of Northeast Artic cod, herring, mackerel, Greenland halibut, tusk, saithe and Atlantic halibut. In total, 923 individual fish samples were analysed. The fish were mostly caught in the open sea off the coast of Norway, from 40 positions. The determination of total arsenic was carried out by inductively coupled plasma mass spectrometry following microwave-assisted wet digestion. The determination of inorganic arsenic was carried out by high-performance liquid chromatography-ICP-MS following microwave-assisted dissolution of the samples. The concentrations found for total arsenic varied greatly between fish species, and ranged from 0.3 to 110 mg kg(-1) wet weight. For inorganic arsenic, the concentrations found were very low (fish used in the recent EFSA opinion on arsenic in food.

  6. Arsenic evolution in fractured bedrock wells in central Maine, USA

    Science.gov (United States)

    Yang, Q.; Zheng, Y.; Culbertson, C.; Schalk, C.; Nielsen, M. G.; Marvinney, R.

    2010-12-01

    Elevated arsenic concentration in fractured bedrock wells has emerged as an important and challenging health problem, especially in rural areas without public water supply and mandatory monitoring of private wells. This has posed risks of skin, bladder, prostate diseases and cancers to private well users. In central Maine, including the study site, 31% of bedrock wells in meta-sedimentary formations have been reported of elevated arsenic concentrations of > 10 µg/L. Geophysical logging and fracture specific water sampling in high arsenic wells have been conducted to understand how water flowing through the aquifers enters the boreholes and how arsenic evolves in the fracture bedrock wells. Two domestic wells in Manchester, Maine, located 50 meter apart with 38 µg/L and 73 µg/L of arsenic in unfiltered water, were investigated to characterize fractures by geophysical logging and to determine flow rates by pumping test. Water samples, representing the bore hole and the fractures, were collected and analyzed for arsenic under ambient and pumping conditions. Transmissivity of the fractures was estimated at 0.23-10.6 m2/day. Water with high dissolved arsenic was supplied primarily by high yielding fractures near the bottom of the borehole. Dissolved arsenic concentrations in borehole water increased as fracture water with high arsenic was replacing borehole water with initially low dissolved arsenic in response to pumping. The precipitation of iron particulates enriched in arsenic was common during and after pumping. Laboratory experiment on well water samples over a period of 16 days suggested that in the borehole arsenic was mainly settled with iron enriched particles, likely amorphous ferric oxyhydroxides, with possibly minor adsorption on the iron minerals. Another bedrock well in Litchfield, Maine, with 478 µg/L of arsenic in the unfiltered well water, is being investigated to quantify and reconstruct of the groundwater flow under ambient and pumping conditions

  7. Performance of aquatic plant species for phytoremediation of arsenic-contaminated water

    Science.gov (United States)

    Jasrotia, Shivakshi; Kansal, Arun; Mehra, Aradhana

    2017-05-01

    This study investigates the effectiveness of aquatic macrophyte and microphyte for phytoremediation of water bodies contaminated with high arsenic concentration. Water hyacinth ( Eichhornia crassipes) and two algae ( Chlorodesmis sp. and Cladophora sp.) found near arsenic-enriched water bodies were used to determine their tolerance toward arsenic and their effectiveness to uptake arsenic thereby reducing organic pollution in arsenic-enriched wastewater of different concentrations. Parameters like pH, chemical oxygen demand (COD), and arsenic concentration were monitored. The pH of wastewater during the course of phytoremediation remained constant in the range of 7.3-8.4, whereas COD reduced by 50-65 % in a period of 15 days. Cladophora sp. was found to survive up to an arsenic concentration of 6 mg/L, whereas water hyacinth and Chlorodesmis sp. could survive up to arsenic concentrations of 2 and 4 mg/L, respectively. It was also found that during a retention period of 10 days under ambient temperature conditions, Cladophora sp. could bring down arsenic concentration from 6 to arsenic by 40-50 %; whereas, water hyacinth could reduce arsenic by only 20 %. Cladophora sp. is thus suitable for co-treatment of sewage and arsenic-enriched brine in an algal pond having a retention time of 10 days. The identified plant species provides a simple and cost-effective method for application in rural areas affected with arsenic problem. The treated water can be used for irrigation.

  8. Dissolved Air Flotation of arsenic adsorbent particles

    Directory of Open Access Journals (Sweden)

    Mario Enrique Santander Muñoz

    2015-01-01

    Full Text Available The removal of arsenic from synthetic effluent was studied using the adsorbent particle flotation technique (APF and dissolved air flotation (DAF. A sample of an iron mineral was used as adsorbent particles of arsenic, ferric chloride as coagulant, cationic poly-acrylamide (NALCO 9808 as flocculants, and sodium oleate as collector. Adsorption studies to determine the pH influence, contact time, and adsorbent particles concentration on the adsorption of arsenic were carried out along with flotation studies to determine the removal efficiency of adsorbents particles. The results achieved indicate that the adsorption kinetic of arsenic is very rapid and that in range of pH’s from 2 to 7 the adsorption percentages remain constant. The equilibrium conditions were achieved in 60 minutes and about 95% of arsenic was adsorbed when used an adsorbent concentration of 2 g/L and pH 6.3. The maximum adsorption capacity of adsorbent particles was 4.96 mg/g. The mean free energy of adsorption (E was found to be 2.63 kJ/mol, which suggests physisorption. The results of the flotation studies demonstrated that when synthetic effluents with 8.9 mg/L of arsenic were treated under the following experimental conditions; 2 g/L of adsorbent particles, 120 mg/L of Fe(III, 2 mg/L of Nalco 9808, 20 mg/L of sodium oleate, and 40% of recycle ratio in the DAF, it was possible to reach 98% of arsenic removal and 6.3 NTU of residual turbidity in clarified synthetic effluent.

  9. Arsenic removal by electrocoagulation process: Recent trends and removal mechanism.

    Science.gov (United States)

    Nidheesh, P V; Singh, T S Anantha

    2017-08-01

    Arsenic contamination in drinking water is a major issue in the present world. Arsenicosis is the disease caused by the regular consumption of arsenic contaminated water, even at a lesser contaminated level. The number of arsenicosis patients is increasing day-by-day. Decontamination of arsenic from the water medium is the only one way to regulate this and the arsenic removal can be fulfilled by water treatment methods based on separation techniques. Electrocoagulation (EC) process is a promising technology for the effective removal of arsenic from aqueous solution. The present review article analyzes the performance of the EC process for arsenic removal. Electrocoagulation using various sacrificial metal anodes such as aluminium, iron, magnesium, etc. is found to be very effective for arsenic decontamination. The performances of each anode are described in detail. A special focus has been made on the mechanism behind the arsenite and arsenate removal by EC process. Main trends in the disposal methods of sludge containing arsenic are also included. Comparison of arsenic decontamination efficiencies of chemical coagulation and EC is also reported. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Arsenic precipitation from metallurgical effluents

    International Nuclear Information System (INIS)

    Navarro, P.; Vargas, C.; Araya, E.; Martin, I.; Alguacil, F. J.

    2004-01-01

    In the mining-metallurgical companies different liquid effluents are produced, which can contain a series of dissolved elements that are considered dangerous from an environmental point of view. One of these elements is the arsenic, especially in the state of oxidation +5 that can be precipitated as calcium or iron arsenate. To fulfil the environmental requests it should have in solution a content of arsenic lower than 0,5 mg/l and the obtained solid product should be very stable under the condition in which it will be stored. this work looks for the best conditions of arsenic precipitation, until achieving contents in solution lower than such mentioned concentration. Also, the stability of the precipitates was studied. (Author) 7 refs

  11. Arsenic contamination in food chain: Thread to food security

    Science.gov (United States)

    Shekhar Azad Kashyap, Chandra; Singh, Swati

    2017-04-01

    The supply of good quality food is a necessity for economic and social health welfare of urban and rural population. Over the last several decades groundwater contamination in developing countries has assumed dangerous levels as a result millions of people are at risk. This is so particularly with respect to arsenic that has registered high concentration in groundwater in countries like India and Bangladesh. The arsenic content in groundwater varies from 10 to 780 µg/L, which is far above the levels for drinking water standards prescribed by World Health Organization (WHO). Currently arsenic has entered in food chain due to irrigation with arsenic contaminated water. In the present study reports the arsenic contamination in groundwater that is being used for irrigating paddy in Manipur and West Bengal. The arsenic content in irrigation water is 475 µg/L and 780 µg/L in Manipur and West Bengal, respectively. In order to assess the effect of such waters on the rice crop, we collected rice plant from Manipur and determined the arsenic content in roots, stem, and grain. The arsenic content in grain varies from 110 to 190 mg/kg while the limit of arsenic intake by humans is 10 mg/kg (WHO). This problem is not confine to the area, it spread global level, and rice being cultivated in these regions is export to the other countries like USA, Middle East and Europe and will be thread to global food security.

  12. Costs of Arsenic Removal Technologies for Small Water Systems: U.S. EPA Arsenic Removal Technology Demonstration Program

    Science.gov (United States)

    As part of the Arsenic Rule Implementation Research Program, between July 2003 and July 2011, the U.S. environmental Protection Agency (EPA) conducted 50 full-scale demonstration projects on treatment systems removing arsenic from drinking water in 26 states throughout the U.S. ...

  13. Spatial modeling for groundwater arsenic levels in North Carolina.

    Science.gov (United States)

    Kim, Dohyeong; Miranda, Marie Lynn; Tootoo, Joshua; Bradley, Phil; Gelfand, Alan E

    2011-06-01

    To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized categories based on rock type and interpreted mode of deposition/emplacement. The geologic transitions from rocks of a primary pyroclastic origin to rocks of volcaniclastic sedimentary origin were designated as polylines. The data were fitted to a left-censored regression model to identify key determinants of arsenic levels in groundwater. A Bayesian spatial random effects model was then developed to capture any spatial patterns in groundwater arsenic residuals into model estimation. Statistical model results indicate (1) wells close to a transition zone or fault are more likely to contain detectible arsenic; (2) welded tuffs and hydrothermal quartz bodies are associated with relatively higher groundwater arsenic concentrations and even higher for those proximal to a pluton; and (3) wells of greater depth are more likely to contain elevated arsenic. This modeling effort informs policy intervention by creating three-dimensional maps of predicted arsenic levels in groundwater for any location and depth in the area.

  14. Arsenic and Environmental Health: State of the Science and ...

    Science.gov (United States)

    Background: Exposure to inorganic and organic arsenic compounds is a major public health problem that affects hundreds of millions of people worldwide. Exposure to arsenic is associated with cancer and noncancer effects in nearly every organ in the body, and evidence is mounting for health effects at lower levels of arsenic exposure than previously thought. Building from a tremendous knowledge base with > 1,000 scientific papers published annually with “arsenic” in the title, the question becomes, what questions would best drive future research directions? Objectives: The objective is to discuss emerging issues in arsenic research and identify data gaps across disciplines. Methods: The National Institutes of Health’s National Institute of Environmental Health Sciences Superfund Research Program convened a workshop to identify emerging issues and research needs to address the multi-faceted challenges related to arsenic and environmental health. This review summarizes information captured during the workshop. Discussion: More information about aggregate exposure to arsenic is needed, including the amount and forms of arsenic found in foods. New strategies for mitigating arsenic exposures and related health effects range from engineered filtering systems to phytogenetics and nutritional interventions. Furthermore, integration of omics data with mechanistic and epidemiological data is a key step toward the goal of linking biomarkers of exposure and suscepti

  15. Spatial Modeling for Groundwater Arsenic Levels in North Carolina

    Science.gov (United States)

    Kim, Dohyeong; Miranda, Marie Lynn; Tootoo, Joshua; Bradley, Phil; Gelfand, Alan E.

    2013-01-01

    To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized categories based on rock type and interpreted mode of deposition/emplacement. The geologic transitions from rocks of a primary pyroclastic origin to rocks of volcaniclastic sedimentary origin were designated as polylines. The data were fitted to a left-censored regression model to identify key determinants of arsenic levels in groundwater. A Bayesian spatial random effects model was then developed to capture any spatial patterns in groundwater arsenic residuals into model estimation. Statistical model results indicate (1) wells close to a transition zone or fault are more likely to contain detectible arsenic; (2) welded tuffs and hydrothermal quartz bodies are associated with relatively higher groundwater arsenic concentrations and even higher for those proximal to a pluton; and (3) wells of greater depth are more likely to contain elevated arsenic. This modeling effort informs policy intervention by creating three-dimensional maps of predicted arsenic levels in groundwater for any location and depth in the area. PMID:21528844

  16. Spatial modeling for groundwater arsenic levels in North Carolina

    Science.gov (United States)

    Kim, D.; Miranda, M.L.; Tootoo, J.; Bradley, P.; Gelfand, A.E.

    2011-01-01

    To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized categories based on rock type and interpreted mode of deposition/emplacement. The geologic transitions from rocks of a primary pyroclastic origin to rocks of volcaniclastic sedimentary origin were designated as polylines. The data were fitted to a left-censored regression model to identify key determinants of arsenic levels in groundwater. A Bayesian spatial random effects model was then developed to capture any spatial patterns in groundwater arsenic residuals into model estimation. Statistical model results indicate (1) wells close to a transition zone or fault are more likely to contain detectible arsenic; (2) welded tuffs and hydrothermal quartz bodies are associated with relatively higher groundwater arsenic concentrations and even higher for those proximal to a pluton; and (3) wells of greater depth are more likely to contain elevated arsenic. This modeling effort informs policy intervention by creating three-dimensional maps of predicted arsenic levels in groundwater for any location and depth in the area. ?? 2011 American Chemical Society.

  17. Biotechnology based processes for arsenic removal

    NARCIS (Netherlands)

    Huisman, J.; Olde Weghuis, M.; Gonzalez-Contreras, P.A.

    2011-01-01

    The regulations for arsenic control have become strict. Therefore, better technologies to remove arsenic from bleeds and effluents are desired. In addition, no single solution is suitable for all cases. The properties of the process streams and the storage facilities are major factors determining

  18. Environmental arsenic exposure, selenium and sputum alpha-1 antitrypsin

    DEFF Research Database (Denmark)

    Burgess, Jefferey L; Kurzius-Spencer, Margaret; Poplin, Gerald S

    2014-01-01

    Exposure to arsenic in drinking water is associated with increased respiratory disease. Alpha-1 antitrypsin (AAT) protects the lung against tissue destruction. The objective of this study was to determine whether arsenic exposure is associated with changes in airway AAT concentration and whether...... this relationship is modified by selenium. A total of 55 subjects were evaluated in Ajo and Tucson, Arizona. Tap water and first morning void urine were analyzed for arsenic species, induced sputum for AAT and toenails for selenium and arsenic. Household tap-water arsenic, toenail arsenic and urinary inorganic...... arsenic and metabolites were significantly higher in Ajo (20.6±3.5 μg/l, 0.54±0.77 μg/g and 27.7±21.2 μg/l, respectively) than in Tucson (3.9±2.5 μg/l, 0.16±0.20 μg/g and 13.0±13.8 μg/l, respectively). In multivariable models, urinary monomethylarsonic acid (MMA) was negatively, and toenail selenium...

  19. Arsenic (III Adsorption Using Palladium Nanoparticles from Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Farzaneh Arsiya

    2017-07-01

    Full Text Available The presence of Arsenic in drinking water is the greatest threat to health effects especially in water. The purpose of this study is application of green palladium nanoparticles for removal of trivalent Arsenic from aqueous solutions and also the impact of some factors such as retention time, pH, concentration of palladium nanoparticles and Arsenic concentrations was studied. The values for Arsenic removal from aqueous solutions were measured by furnace atomic adsorption spectrometry (Conter AA700. In the study, Langmuir and Freundlich isotherm models and pseudo-second order kinetic model were studied. The results of  optimization is shown that 0.5 g of nanoparticles can removed %99.8 of Arsenic with initial concentration of  0.5 g/l, in 5 minutes at pH=4. Langmuir model, Freundlich model (R2=0.94 and pseudo-second order kinetic model (R2=0.99 shown high correlation for removing of Arsenic from aqueous solutions. It was found, palladium nanoparticles can be used as an efficient method to remove Arsenic from aqueous solutions in a short time.

  20. Groundwater arsenic concentrations in Vietnam controlled by sediment age

    DEFF Research Database (Denmark)

    Postma, Dieke; Larsen, Flemming; Thai, Nguyen Thi

    2012-01-01

    Arsenic contamination of groundwater continues to threaten the health of millions of people in southeast Asia. The oxidation of organic carbon, coupled to the reductive dissolution of arsenic-bearing iron oxides, is thought to control the release of sediment-bound arsenic into groundwater. However......, the cause of the high spatial variability in groundwater arsenic concentrations—which can range from 5 to 500 μg l−1 within distances of a few kilometres—has been uncertain. Here, we combine measurements of sediment age, organic-matter reactivity and water chemistry at four locations along a cross......-section of the arsenic-contaminated Red River floodplain in Vietnam to determine the origin of variations in groundwater arsenic concentrations. The burial age of the aquifer sediments, determined using optical stimulated luminescence, ranged from 460 years near the course of the present-day river to 5,900 years...