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  1. Targeting catalase but not peroxiredoxins enhances arsenic trioxide-induced apoptosis in K562 cells.

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    Li-Li Song

    Full Text Available Despite considerable efficacy of arsenic trioxide (As2O3 in acute promyelocytic leukemia (APL treatment, other non-APL leukemias, such as chronic myeloid leukemia (CML, are less sensitive to As2O3 treatment. However, the underlying mechanism is not well understood. Here we show that relative As2O3-resistant K562 cells have significantly lower ROS levels than As2O3-sensitive NB4 cells. We compared the expression of several antioxidant enzymes in these two cell lines and found that peroxiredoxin 1/2/6 and catalase are expressed at high levels in K562 cells. We further investigated the possible role of peroxirdoxin 1/2/6 and catalase in determining the cellular sensitivity to As2O3. Interestingly, knockdown of peroxiredoxin 1/2/6 did not increase the susceptibility of K562 cells to As2O3. On the contrary, knockdown of catalase markedly enhanced As2O3-induced apoptosis. In addition, we provide evidence that overexpression of BCR/ABL cannot increase the expression of PRDX 1/2/6 and catalase. The current study reveals that the functional role of antioxidant enzymes is cellular context and treatment agents dependent; targeting catalase may represent a novel strategy to improve the efficacy of As2O3 in CML treatment.

  2. Endoplasmic reticulum stress mediates the arsenic trioxide-induced apoptosis in human hepatocellular carcinoma cells.

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    Zhang, Xin-Yu; Yang, Shu-Meng; Zhang, Hao-Peng; Yang, Yue; Sun, Shi-Bo; Chang, Jian-Ping; Tao, Xuan-Chen; Yang, Tuo-Yun; Liu, Chun; Yang, Yan-Mei

    2015-11-01

    Arsenic trioxide has been proven to trigger apoptosis in human hepatocellular carcinoma cells. Endoplasmic reticulum stress has been known to be involved in apoptosis through the induction of CCAAT/enhancer-binding protein homologous protein. However, it is unknown whether endoplasmic reticulum stress mediates arsenic trioxide-induced apoptosis in human hepatocellular carcinoma cells. Our data showed that arsenic trioxide significantly induced apoptosis in human hepatocellular carcinoma cells. Furthermore, arsenic trioxide triggered endoplasmic reticulum stress, as indicated by endoplasmic reticulum dilation, upregulation of glucose-regulated protein 78 and CCAAT/enhancer-binding protein homologous protein. We further found that 4-phenylbutyric acid, an inhibitor of endoplasmic reticulum stress, alleviated arsenic trioxide-induced expression of CCAAT/enhancer-binding protein homologous protein. More important, knockdown of CCAAT/enhancer-binding protein homologous protein by siRNA or inhibition of endoplasmic reticulum stress by 4-phenylbutyric acid alleviated apoptosis induced by arsenic trioxide. Consequently, our results suggested that arsenic trioxide could induce endoplasmic reticulum stress-mediated apoptosis in hepatocellular carcinoma cells, and that CCAAT/enhancer-binding protein homologous protein might play an important role in this process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Melatonin enhances arsenic trioxide-induced cell death via sustained upregulation of Redd1 expression in breast cancer cells.

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    Yun, Sun-Mi; Woo, Sang Hyeok; Oh, Sang Taek; Hong, Sung-Eun; Choe, Tae-Boo; Ye, Sang-Kyu; Kim, Eun-Kyu; Seong, Min Ki; Kim, Hyun-A; Noh, Woo Chul; Lee, Jin Kyung; Jin, Hyeon-Ok; Lee, Yun-Han; Park, In-Chul

    2016-02-15

    Melatonin is implicated in various physiological functions, including anticancer activity. However, the mechanism(s) of its anticancer activity is not well understood. In the present study, we investigated the combined effects of melatonin and arsenic trioxide (ATO) on cell death in human breast cancer cells. Melatonin enhanced the ATO-induced apoptotic cell death via changes in the protein levels of Survivin, Bcl-2, and Bax, thus affecting cytochrome c release from the mitochondria to the cytosol. Interestingly, we found that the cell death induced by co-treatment with melatonin and ATO was mediated by sustained upregulation of Redd1, which was associated with increased production of reactive oxygen species (ROS). Combined treatment with melatonin and ATO induced the phosphorylation of JNK and p38 MAP kinase downstream from Redd1 expression. Rapamycin and S6K1 siRNA enhanced, while activation of mTORC1 by transfection with TSC2 siRNA suppressed the cell death induced by melatonin and ATO treatment. Taken together, our findings suggest that melatonin enhances ATO-induced apoptotic cell death via sustained upregulation of Redd1 expression and inhibition of mTORC1 upstream of the activation of the p38/JNK pathways in human breast cancer cells. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  4. The Protective Role of Resveratrol against Arsenic Trioxide-Induced Cardiotoxicity

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    Weiqian Zhang

    2013-01-01

    Full Text Available Arsenic trioxide (As2O3 shows substantial anticancer activity in patients with acute promyelocytic leukemia (APL. Unfortunately, limiting the application of this effective agent to APL patients is severe cardiotoxicity. Resveratrol, the natural food-derived polyphenolic compound, is well known for its antioxidant properties and protects the cardiovascular system. But the potential role of resveratrol against As2O3 in heart via nuclear factor erythroid 2-related factor 2 (Nrf2 and heme oxygenase-1 (HO-1 is unclear. The present study evaluated the effects of pretreatment with resveratrol and As2O3 on oxidative stress and cardiac dysfunction in rat. In the present study, resveratrol decreased As2O3-induced reactive oxygen species generation, oxidative DNA damage, and pathological alterations. In addition, cardiac dysfunction parameters, intracellular calcium and arsenic accumulation, glutathione redox ratio, and cAMP deficiency levels were observed in As2O3-treated rats; these changes were attenuated by resveratrol. Furthermore, resveratrol significantly prohibited the downregulation of both Nrf2 and HO-1 gene expressions that were downregulated by As2O3, whereas resveratrol did not alter As2O3-induced nitric oxide formation. Thus, the protective role of resveratrol against As2O3-induced cardiotoxicity is implemented by the maintenance of redox homeostasis (Nrf2-HO-1 pathway and facilitating arsenic efflux. Our findings suggest coadministration with resveratrol, and As2O3 might provide a novel therapeutic strategy for APL.

  5. Autocrine human growth hormone increases sensitivity of mammary carcinoma cell to arsenic trioxide-induced apoptosis.

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    Zekri, Ali; Ghaffari, Seyed H; Yousefi, Meysam; Ghanizadeh-Vesali, Samad; Mojarrad, Majid; Alimoghaddam, Kamran; Ghavamzadeh, Ardeshir

    2013-09-05

    Human growth hormone (hGH) has been increasingly implicated in a variety of cancers; its up-regulation is observed in breast cancer and correlates with a poor outcome. Autocrine hGH promotes mammary carcinoma cell survival, proliferation, immortalization; it confers an invasive phenotype as a result of an epithelial-mesenchymal transition and contributes to chemoresistance and radioresistance. Arsenic trioxide (ATO) is being successfully used as a first and second line therapy for the treatment of patients with acute promyelocytic leukemia. It also inhibits tumor cell growth and induces apoptosis in a broad range of solid tumors. In the present study, we investigated the effect of hGH on sensitivity of a mammary adenocarcinoma cell to ATO, using a stable hGH-transfectant MCF-7 cell line, MCF7-hGH. Our results demonstrated for the first time that the overexpression of hGH increased sensitivity of the breast cancer cell line MCF-7 to ATO through apoptotic and anti-proliferative mechanisms. The effect of ATO on the transcriptional level of genes involved in survival (Bcl-2, Bax and Survivin), self-sufficiency in growth signals (c-Myc, ARF, Cdc25A, p53 and Bax), immortalization (hTERT) and invasion and metastasis (MMP-2 and MMP-9, uPA and uPAR and E-cadherin) was more pronounced in MCF7-hGH compared with its parental MCF-7 line. Our study may highlight the potential application of ATO for the treatment of patients with breast cancer, especially in those who have metastatic and chemoresistant tumor phenotype possibly due to the over expression of hGH. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  6. Arsenic trioxide induces the apoptosis of human breast cancer MCF-7 cells through activation of caspase-3 and inhibition of HERG channels.

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    Wang, Ying; Zhang, Yong; Yang, Lei; Cai, Benzhi; Li, Jianping; Zhou, You; Yin, Li; Yang, Lili; Yang, Bao Feng; Lu, Yan Jie

    2011-05-01

    Arsenic trioxide (As(2)O(3)) has been widely used to treat patients with acute promyelocytic leukemia and has also been shown to exhibit therapeutic effects on various types of solid tumors, including gastric cancer and lung carcinoma. Breast cancer is a type of solid tumor whose incidence has been increasing for many years. The present study was designed to investigate the effects of As(2)O(3) on the human breast cancer cell line MCF-7, and to explore its potential mechanisms. The MTT assay demonstrated that As(2)O(3) decreased the cellular viability of MCF-7 cells in a concentration-dependent manner. Morphological observation, the TUNEL assay and flow cytometric analysis revealed that apoptosis was involved in the process. An assay for caspase-3 activity suggested that the apoptosis was mediated through caspase-3 activation. Further investigation indicated that protein levels of the human ether-a-go-go-related gene (HERG) were markedly downregulated by As(2)O(3). Taken together, the results indicate that arsenic trioxide induces the apoptosis of human breast cancer MCF-7 cells at least in part through the activation of caspase-3 and the decrease in HERG expression.

  7. Sumoylation of the Tumor Suppressor Promyelocytic Leukemia Protein Regulates Arsenic Trioxide-Induced Collagen Synthesis in Osteoblasts

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    Wen-Xiao Xu

    2015-11-01

    Full Text Available Background/Aims: Promyelocytic leukemia (PML protein is a tumor suppressor that fuses with retinoic acid receptor-α (PML-RARα to contribute to the initiation of acute promyelocytic leukemia (APL. Arsenic trioxide (ATO upregulates expression of TGF-β1, promoting collagen synthesis in osteoblasts, and ATO binds directly to PML to induce oligomerization, sumoylation, and ubiquitination. However, how ATO upregulates TGF-β1 expression is uncertain. Thus, we suggested that PML sumoylation is responsible for regulation of TGF-β1 protein expression. Methods: Kunming mice were treated with ATO, and osteoblasts were counted under scanning electron microscopy. Masson's staining was used to quantify collagen content. hFOB1.19 cells were transfected with siRNA against UBC9 or RNF4, and then treated with ATO or FBS. TGF-β1, PML expression, and sumoylation were quantified with Western blot, and collagen quantified via immunocytochemistry. Results: ATO enhanced osteoblast accumulation, collagen synthesis, and PML-NB formation in vivo. Knocking down UBC9 in hFOB1.19 cells inhibited ATO- and FBS-induced PML sumoylation, TGF-β1 expression, and collagen synthesis. Conversely, knocking down RNF4 enhanced ATO- and FBS-induced PML sumoylation, TGF-β1 expression, and collagen synthesis. Conclusion: These data suggest that PML sumoylation is required for ATO-induced collagen synthesis in osteoblasts.

  8. Requirement of PML SUMO interacting motif for RNF4- or arsenic trioxide-induced degradation of nuclear PML isoforms.

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    Mohamed Ali Maroui

    Full Text Available PML, the organizer of nuclear bodies (NBs, is expressed in several isoforms designated PMLI to VII which differ in their C-terminal region due to alternative splicing of a single gene. This variability is important for the function of the different PML isoforms. PML NB formation requires the covalent linkage of SUMO to PML. Arsenic trioxide (As₂O₃ enhances PML SUMOylation leading to an increase in PML NB size and promotes its interaction with RNF4, a poly-SUMO-dependent ubiquitin E3 ligase responsible for proteasome-mediated PML degradation. Furthermore, the presence of a bona fide SUMO Interacting Motif (SIM within the C-terminal region of PML seems to be required for recruitment of other SUMOylated proteins within PML NBs. This motif is present in all PML isoforms, except in the nuclear PMLVI and in the cytoplasmic PMLVII. Using a bioluminescence resonance energy transfer (BRET assay in living cells, we found that As₂O₃ enhanced the SUMOylation and interaction with RNF4 of nuclear PML isoforms (I to VI. In addition, among the nuclear PML isoforms, only the one lacking the SIM sequence, PMLVI, was resistant to As₂O₃-induced PML degradation. Similarly, mutation of the SIM in PMLIII abrogated its sensitivity to As₂O₃-induced degradation. PMLVI and PMLIII-SIM mutant still interacted with RNF4. However, their resistance to the degradation process was due to their inability to be polyubiquitinated and to recruit efficiently the 20S core and the β regulatory subunit of the 11S complex of the proteasome in PML NBs. Such resistance of PMLVI to As₂O₃-induced degradation was alleviated by overexpression of RNF4. Our results demonstrate that the SIM of PML is dispensable for PML SUMOylation and interaction with RNF4 but is required for efficient PML ubiquitination, recruitment of proteasome components within NBs and proteasome-dependent degradation of PML in response to As₂O₃.

  9. Arsenic trioxide-induced osteo-necrosis treatment in a child: mini-review and case report.

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    Marty, M; Noirrit-Esclassan, E; Diemer, F

    2016-10-01

    Arsenic oxide compounds were traditionally used as devitalizing agents. Due to its toxicity, leakage of such compounds into the periodontium can cause gingival and osteo-necrosis. Their use is forbidden in Europe and the USA for decades, however, some dentists seem to still use it. We report the case of a 14-year-old girl referred to the paediatric dentistry department of Toulouse University hospital, France, presenting a bone necrosis following the use of an arsenic trioxide product to accelerate pulp necrosis. The treatment included surgical removal of necrosis bone sequestrum, complete pulpectomy and an intermediate restoration of the tooth 27. After 1 week, the clinical conditions greatly improved. A restoration using a ceramic crown was performed after 2 months, and complete healing was observed after 1 year follow-up. Although arsenic trioxide is neither appropriate nor permitted for use in modern dentistry, especially in paediatric dentistry, some rare cases of arsenic-induced osteo-necrosis can still be encountered. A clearer message must be given to all dental practitioners against the use of arsenic trioxide in modern endodontic treatment.

  10. TG-interacting factor transcriptionally induced by AKT/FOXO3A is a negative regulator that antagonizes arsenic trioxide-induced cancer cell apoptosis

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    Liu, Zi-Miao; Tseng, Hong-Yu; Cheng, Ya-Ling [Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan (China); Yeh, Bi-Wen [Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan (China); Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Department of Urology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Wu, Wen-Jeng [Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Department of Urology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Huang, Huei-Sheng, E-mail: huanghs@mail.ncku.edu.tw [Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan (China)

    2015-05-15

    Arsenic trioxide (ATO) is a multi-target drug approved by the Food and Drug Administration as the first-line chemotherapeutic agent for the treatment of acute promyelocytic leukemia. In addition, several clinical trials are being conducted with arsenic-based drugs for the treatment of other hematological malignancies and solid tumors. However, ATO's modest clinical efficacy on some cancers, and potential toxic effects on humans have been reported. Determining how best to reduce these adverse effects while increasing its therapeutic efficacy is obviously a critical issue. Previously, we demonstrated that the JNK-induced complex formation of phosphorylated c-Jun and TG-interacting factor (TGIF) antagonizes ERK-induced cyclin-dependent kinase inhibitor CDKN1A (p21{sup WAF1/CIP1}) expression and resultant apoptosis in response to ATO in A431 cells. Surprisingly, at low-concentrations (0.1–0.2 μM), ATO increased cellular proliferation, migration and invasion, involving TGIF expression, however, at high-concentrations (5–20 μM), ATO induced cell apoptosis. Using a promoter analysis, TGIF was transcriptionally regulated by ATO at the FOXO3A binding site (− 1486 to − 1479 bp) via the c-Src/EGFR/AKT pathway. Stable overexpression of TGIF promoted advancing the cell cycle into the S phase, and attenuated 20 μM ATO-induced apoptosis. Furthermore, blockage of the AKT pathway enhanced ATO-induced CDKN1A expression and resultant apoptosis in cancer cells, but overexpression of AKT1 inhibited CDKN1A expression. Therefore, we suggest that TGIF is transcriptionally regulated by the c-Src/EGFR/AKT pathway, which plays a role as a negative regulator in antagonizing ATO-induced CDKN1A expression and resultant apoptosis. Suppression of these antagonistic effects might be a promising therapeutic strategy toward improving clinical efficacy of ATO. - Highlights: • ATO-induced biphasic survival responses of cancer cells depend on low- or high-concentrations. • TGIF

  11. Activation of the Nrf2 Signaling Pathway Involving KLF9 Plays a Critical Role in Allicin Resisting Against Arsenic Trioxide-Induced Hepatotoxicity in Rats.

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    Yang, Daqian; Lv, Zhanjun; Zhang, Haili; Liu, Biying; Jiang, Huijie; Tan, Xiao; Lu, Jingjing; Baiyun, Ruiqi; Zhang, Zhigang

    2017-03-01

    Arsenic trioxide (As 2 O 3 ) is both the most prevalent, naturally occurring inorganic arsenical threatening human health and an efficient therapeutic for acute promyelocytic leukemia. Regretfully, As 2 O 3 -treated cancer patients often suffer from hepatotoxicity. While effective antioxidant and anticarcinogenic actions of allicin have previously been demonstrated, studies indicating how allicin affects As 2 O 3 -induced hepatotoxicity and arsenic accumulation are lacking. Our study, for the first time, elaborates potential details of the hepatoprotective mechanisms of allicin against As 2 O 3 -induced liver injury. Wistar rats were administrated allicin (30 mg/kg) 1 h before As 2 O 3 (3 mg/kg) by daily gavage for 2 weeks. Our results indicate that allicin ameliorated As 2 O 3 -induced liver dysfunction, oxidative stress, and arsenic accumulation in the liver. Meanwhile, allicin decreased NF-κB level and upregulated expression of proteins reduced by As 2 O 3 including nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1, nicotinamide adenine dinucleotide phosphate:quinone oxidoreductase 1, and Krüppel-like factor 9 (KLF9). In addition, allicin promoted B cell lymphoma-extra large expression and suppressed B cell lymphoma-2-associated X protein levels regulated by As 2 O 3 . However, neither allicin nor As 2 O 3 affected cytochrome P450 2E1 mRNA expression. In conclusion, allicin attenuated As 2 O 3 -induced hepatotoxicity by activating the Nrf2 signaling pathway involving KLF9 to inhibit oxidative stress and apoptosis. Our findings elucidate a detailed mechanism by which allicin provides protection against As 2 O 3 -induced liver injury and support its potential role as an adjunctive therapy for patients suffering from chronic arsenic exposure.

  12. Arsenic trioxide-induced growth arrest of breast cancer MCF-7 cells involving FOXO3a and IκB kinase β expression and localization.

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    Liu, Wenlou; Gong, Yusen; Li, Haili; Jiang, Guan; Zhan, Shining; Liu, Hong; Wu, Yongping

    2012-10-01

    Currently, arsenic has been clinically investigated as a therapeutic agent for a variety of solid malignancies, including breast cancer. However, the exact underlying molecular mechanisms through which arsenic trioxide (As(2)O(3)) induces cell growth arrest and apoptosis in solid tumors have not been clearly understood. The aim of our study was to gain an insight into the effect of As(2)O(3) on the human breast cancer MCF-7 cell line and investigate cell growth inhibition, apoptosis, and the molecular mechanism after As(2)O(3) treatment in MCF-7 cells. Expression of FOXO3a, nuclear-FOXO3a, caspase-3, and IκB kinase β (IKKβ) mRNA levels in MCF-7 cells was determined by reverse transcription-polymerase chain reaction (RT-PCR). The protein expression was examined by the Western blot analysis and immunocytochemical staining. The distribution of apoptotic cells was assessed by flow cytometry, and the morphology of the apoptotic cells was investigated by Hoechest33258 staining. Our results showed that As(2)O(3) significantly induced the apoptosis of MCF-7 cells tested in this study in a dose-dependent manner. As(2)O(3) induced the decrease of IKKβ expression and the increase of total as well as nuclear FOXO3a expression, which triggered the phosphorylation of cytoplasmic FOXO3a at the Thr32 residue decrease. RT-PCR, Western blot analysis, and immunocytochemistry revealed that the expression of IKKβ in MCF-7 cells was upregulated when As(2)O(3) was combined with tumor necrosis factor-α (TNF-α), whereas the expression of FOXO3a was downregulated in comparison with the As(2)O(3)-alone group. These findings indicated a specific molecular mechanism by which MCF-7 cell lines were susceptible to the As(2)O(3) therapy through FOXO3a expression and localization. This FOXO3a accumulation may be well correlated with the As(2)O(3)-induced reduction of active IKKβ, which may provide new insights into As(2)O(3)-related signaling activities.

  13. BIM-mediated AKT phosphorylation is a key modulator of arsenic trioxide-induced apoptosis in cisplatin-sensitive and -resistant ovarian cancer cells.

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    Zhu Yuan

    Full Text Available Chemo-resistance to cisplatin-centered cancer therapy is a major obstacle to the effective treatment of human ovarian cancer. Previous reports indicated that arsenic trioxide (ATO induces cell apoptosis in both drug-sensitive and -resistant ovarian cancer cells.In this study, we determined the molecular mechanism of ATO-induced apoptosis in ovarian cancer cells. Our data demonstrated that ATO induced cell apoptosis by decreasing levels of phosphorylated AKT (p-AKT and activating caspase-3 and caspase-9. Importantly, BIM played a critical role in ATO-induced apoptosis. The inhibition of BIM expression prevented AKT dephosphorylation and inhibited caspase-3 activation during cell apoptosis. However, surprisingly, gene silencing of AKT or FOXO3A had little effect on BIM expression and phosphorylation. Moreover, the activation of caspase-3 by ATO treatment improved AKT dephosphorylation, not only by cleaving the regulatory A subunit of protein phosphatase 2A (PP2A, but also by increasing its activation. Furthermore, our data indicated that the c-Jun N-terminal kinases (JNK pathway is involved in the regulation of BIM expression.We demonstrated the roles of BIM in ATO-induced apoptosis and the molecular mechanisms of BIM expression regulated by ATO during ovarian cancer cell apoptosis. Our findings suggest that BIM plays an important role in regulating p-AKT by activating caspase-3 and that BIM mediates the level of AKT phosphorylation to determine the threshold for overcoming cisplatin resistance in ovarian cancer cells.

  14. Polyphenol-rich apple (Malus domestica L.) peel extract attenuates arsenic trioxide induced cardiotoxicity in H9c2 cells via its antioxidant activity.

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    Vineetha, Vadavanath Prabhakaran; Girija, Seetharaman; Soumya, Rema Sreenivasan; Raghu, Kozhiparambil Gopalan

    2014-03-01

    Evidences suggest that apple peel has a wide range of polyphenols having antioxidant activity and its consumption has been linked with improved health benefits. Arsenic trioxide (ATO) is a very effective drug for the treatment of acute promyelocytic leukemia (APL) but it leads to cardiotoxicity mediated through alterations in various cardiac ion channels and by increasing the intracellular calcium level and reactive oxygen species (ROS). The aim of the present investigation was to study the effect of methanolic extract of apple peel (APME) and aqueous extract of apple peel (APAE) on ATO (5 μM) induced toxicity in the H9c2 cardiac myoblast cell line. We estimated the cellular status of innate antioxidant enzymes, level of ROS, mitochondrial superoxide, glutathione and intracellular calcium with ATO and apple peel extracts. Prior to the cell line based study, we had evaluated the antioxidant potential of apple peel extract by 1,1-diphenyl-2-picrylhydrazyl (DPPH), total reducing power (TRP), superoxide anion and hydroxyl radical scavenging activity, in addition to quantifying total phenolic and flavonoid content. Both the extracts showed considerable antioxidant activity in cell-free chemical assays. In addition, both APME and APAE prevented the alteration in antioxidant status induced by ATO in H9c2 cells. Significant differential alterations had been observed in the activity of lactate dehydrogenase, superoxide dismutase, catalase, glutathione, glutathione peroxidase, thioredoxin reductase, xanthine oxidase, calcium overload and caspase 3 activity with ATO. The overall result revealed the protective property of polyphenol-rich apple peel extract against ATO induced cardiac toxicity via its antioxidant activity.

  15. E2F1-mediated FOS induction in arsenic trioxide-induced cellular transformation: effects of global H3K9 hypoacetylation and promoter-specific hyperacetylation in vitro.

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    Rahman, Sunniyat; Housein, Zjwan; Dabrowska, Aleksandra; Mayán, Maria Dolores; Boobis, Alan R; Hajji, Nabil

    2015-05-01

    Aberrant histone acetylation has been observed in carcinogenesis and cellular transformation associated with arsenic exposure; however, the molecular mechanisms and cellular outcomes of such changes are poorly understood. We investigated the impact of tolerated and toxic arsenic trioxide (As2O3) exposure in human embryonic kidney (HEK293T) and urothelial (UROtsa) cells to characterize the alterations in histone acetylation and gene expression as well as the implications for cellular transformation. Tolerated and toxic exposures of As2O3 were identified by measurement of cell death, mitochondrial function, cellular proliferation, and anchorage-independent growth. Histone extraction, the MNase sensitivity assay, and immunoblotting were used to assess global histone acetylation levels, and gene promoter-specific interactions were measured by chromatin immunoprecipitation followed by reverse-transcriptase polymerase chain reaction. Tolerated and toxic dosages, respectively, were defined as 0.5 μM and 2.5 μM As2O3 in HEK293T cells and 1 μM and 5 μM As2O3 in UROtsa cells. Global hypoacetylation of H3K9 at 72 hr was observed in UROtsa cells following tolerated and toxic exposure. In both cell lines, tolerated exposure alone led to H3K9 hyperacetylation and E2F1 binding at the FOS promoter, which remained elevated after 72 hr, contrary to global H3K9 hypoacetylation. Thus, promoter-specific H3K9 acetylation is a better predictor of cellular transformation than are global histone acetylation patterns. Tolerated exposure resulted in an increased expression of the proto-oncogenes FOS and JUN in both cell lines at 72 hr. Global H3K9 hypoacetylation and promoter-specific hyperacetylation facilitate E2F1-mediated FOS induction in As2O3-induced cellular transformation.

  16. Demethylation and alterations in the expression level of the cell cycle-related genes as possible mechanisms in arsenic trioxide-induced cell cycle arrest in human breast cancer cells.

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    Moghaddaskho, Farima; Eyvani, Haniyeh; Ghadami, Mohsen; Tavakkoly-Bazzaz, Javad; Alimoghaddam, Kamran; Ghavamzadeh, Ardeshir; Ghaffari, Seyed H

    2017-02-01

    Arsenic trioxide (As2O3) has been used clinically as an anti-tumor agent. Its mechanisms are mostly considered to be the induction of apoptosis and cell cycle arrest. However, the detailed molecular mechanisms of its anti-cancer action through cell cycle arrest are poorly known. Furthermore, As2O3 has been shown to be a potential DNA methylation inhibitor, inducing DNA hypomethylation. We hypothesize that As2O3 may affect the expression of cell cycle regulatory genes by interfering with DNA methylation patterns. To explore this, we examined promoter methylation status of 24 cell cycle genes in breast cancer cell lines and in a normal breast tissue sample by methylation-specific polymerase chain reaction and/or restriction enzyme-based methods. Gene expression level and cell cycle distribution were quantified by real-time polymerase chain reaction and flow cytometric analyses, respectively. Our methylation analysis indicates that only promoters of RBL1 (p107), RASSF1A, and cyclin D2 were aberrantly methylated in studied breast cancer cell lines. As2O3 induced CpG island demethylation in promoter regions of these genes and restores their expression correlated with DNA methyltransferase inhibition. As2O3 also induced alterations in messenger RNA expression of several cell cycle-related genes independent of demethylation. Flow cytometric analysis revealed that the cell cycle arrest induced by As2O3 varied depending on cell lines, MCF-7 at G1 phase and both MDA-MB-231 and MDA-MB-468 cells at G2/M phase. These changes at transcriptional level of the cell cycle genes by the molecular mechanisms dependent and independent of demethylation are likely to represent the mechanisms of cell cycle redistribution in breast cancer cells, in response to As2O3 treatment.

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

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    Wei Shuhe [Key Laboratory of Terrestrial Ecological Processes, Institute of Applied Ecology, Shenyang 110116 (China); Ma, Lena Q., E-mail: lqma@ufl.ed [Key Laboratory of Terrestrial Ecological Processes, Institute of Applied Ecology, Shenyang 110116 (China); Soil and Water Science Department, University of Florida, Gainesville, FL 32611-0290 (United States); Saha, Uttam; Mathews, Shiny [Soil and Water Science Department, University of Florida, Gainesville, FL 32611-0290 (United States); Sundaram, Sabarinath; Rathinasabapathi, Bala [Horticultural Sciences Department, University of Florida, Gainesville, FL 32611-0690 (United States); Zhou Qixing [Key Laboratory of Terrestrial Ecological Processes, Institute of Applied Ecology, Shenyang 110116 (China)

    2010-05-15

    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{sup -1}) with sulfate (6.4, 12.8 or 25.6 mg S L{sup -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.

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

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    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...... concentration the signal intensities achieved were about 4500-5000 counts s-1 per ng ml-1 of arsenic and about 700-1100 counts s-1 per ng ml-1 of selenium (Se-82), corresponding to enhancement factors of 3.5-4.5 compared with aqueous solution for the two elements. Differences in sensitivity (calculated...... on the basis of analyte atom) were observed between the individual arsenic species and between the selenium species in aqueous as well as in carbon-added solutions. The presence of 3% v/v methanol in the analyte solutions doubled the level of the background signal for arsenic and selenium, but its fluctuation...

  19. Studying arsenic trioxide-induced apoptosis of Colo-16 cells with ...

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    nj tonukari

    2011-10-10

    Oct 10, 2011 ... Detection of DNA fragmentation with electrophoresis and nuclear morphological observation with two- photon laser scanning microscopy. Cells die either following necrosis or apoptosis. Apoptosis. (programmed cell death) is an important feature of normal development as well as various disease states,.

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

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Min; Schmidt, Robin H.; Beier, Juliane I. [Department of Pharmacology and Toxicology, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); Department of Medicine, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); Watson, Walter H. [Department of Medicine, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); University of Louisville Alcohol Research Center, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); Zhong, Hai [Department of Pharmacology and Toxicology, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); University of Louisville Alcohol Research Center, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States); States, J. Christopher [Department of Pharmacology and Toxicology, 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); University of Louisville Alcohol Research Center, University of Louisville Health Sciences Center, Louisville, KY 40292 (United States)

    2011-12-15

    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: Black-Right-Pointing-Pointer Characterizes a mouse model of arsenic enhanced NAFLD. Black-Right-Pointing-Pointer Arsenic synergistically enhances experimental fatty liver disease at concentrations that cause no overt hepatotoxicity alone. Black-Right-Pointing-Pointer This effect is associated with increased inflammation.

  1. Arsenic trioxide causes redistribution of cell cycle, caspase activation, and GADD expression in human colonic, breast, and pancreatic cancer cells.

    Science.gov (United States)

    Li, Xinquan; Ding, Xianzhong; Adrian, Thomas E

    2004-01-01

    Arsenic trioxide is valuable for treatment of promyelocytic leukemia, but less attention has been paid to its therapeutic potential for other cancers. In this study, the effects of arsenic trioxide were tested in human pancreatic (AsPC-1), colonic (HT-29), and breast (MCF-7) cancer cells. In all three cancer cell lines, arsenic trioxide inhibited proliferation in a concentration and time-dependent manner, as measured by 3H-methyl thymidine incorporation and cell counting. Coincident with inhibition of growth, arsenic trioxide induced marked morphologic changes, including reduced cytoplasmic volume, membrane blebbing, and nuclear condensation consistent with apoptosis. Propidium iodide DNA staining at 24 hours revealed cell cycle arrest in the G0/G1 phase and an increase in the S phase, while at 72 hr there was G2/M phase arrest with a marked increase in the sub-G0/G1, apoptotic cell population. The DNA fragmentation induced by arsenic trioxide was confirmed by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay in all cell lines. Western blot analysis revealed activation of caspase -3, -7, and -9 by arsenic trioxide. Caspase-3 activity was confirmed by demonstrating cleavage of its downstream target, poly ADP-ribose polymerase (PARP). Expression of the antiapoptosis protein, Bcl-2, was time-dependently decreased. In contrast, arsenic trioxide markedly enhanced the expression of the p21 protein, GADD45 and GADD153, in a time-dependent manner. These findings suggest that arsenic trioxide has potential as a therapeutic agent for these cancers.

  2. 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

  3. Abiotic reductive extraction of arsenic from contaminated soils enhanced by complexation: Arsenic extraction by reducing agents and combination of reducing and chelating agents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Jung [Department of Bioactive Material Sciences, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of); Lee, Jae-Cheol [Department of Environmental Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of); Baek, Kitae, E-mail: kbaek@jbnu.ac.kr [Department of Bioactive Material Sciences, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of); Department of Environmental Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Jeollabukdo 561-675 (Korea, Republic of)

    2015-02-11

    Highlights: • Abiotic reductive extraction of As from contaminated soils was studied. • Oxalate/ascorbate were effective in extracting As bound to amorphous iron oxides. • Reducing agents were not effective in extracting As bound to crystalline oxides. • Reductive As extraction was greatly enhanced by complexation. • Combination of dithionite and EDTA could extract about 90% of the total As. - Abstract: Abiotic reductive extraction of arsenic from contaminated soils was studied with various reducing agents and combinations of reducing and chelating agents in order to remediate arsenic-contaminated soils. Oxalate and ascorbic acid were effective to extract arsenic from soil in which arsenic was associated with amorphous iron oxides, but they were not effective to extract arsenic from soils in which arsenic was bound to crystalline oxides or those in which arsenic was mainly present as a scorodite phase. An X-ray photoelectron spectroscopy study showed that iron oxides present in soils were transformed to Fe(II,III) or Fe(II) oxide forms such as magnetite (Fe{sub 3}O{sub 4}, Fe{sup II}Fe{sub 2}{sup III}O{sub 4}) by reduction with dithionite. Thus, arsenic extraction by dithionite was not effective due to the re-adsorption of arsenic to the newly formed iron oxide phase. Combination of chelating agents with reducing agents greatly improved arsenic extraction from soil samples. About 90% of the total arsenic could be extracted from all soil samples by using a combination of dithionite and EDTA. Chelating agents form strong complexation with iron, which can prevent precipitation of a new iron oxide phase and also enhance iron oxide dissolution via a non-reductive dissolution pathway.

  4. Removal of arsenic by enhanced coagulation and membrane technology

    Energy Technology Data Exchange (ETDEWEB)

    Chang, S.D.; Ruiz, H. [CH2M Hill, Santa Ana, CA (United States); Bellamy, W.D. [CH2M Hill, Englewood, CO (United States); Spangenberg, C.W.; Clark, D.L. [Irvine Ranch Water District, Irvine, CA (United States)

    1994-12-31

    The US EPA is promulgating a new MCL for arsenic based on epidemiology studies. The concern from the water industry is that the new MCL will be significantly lower than the current MCL of 50 {micro}g/L. The new MCL, some speculate may be as low as 2 {micro}g/L or less, is expected to have a significant impact on water utilities that depend on groundwater supply or use aquifer storage and recovery technology for potable water resources. A questionnaire sent to the participants at the Arsenic Workshop (May, 1993) sponsored by Association of California Water Agencies and the Metropolitan Water District of Southern California indicated that 66% of the 50 water agencies responded will not be in compliance if the new MCL is set at 5 AGIL. The issues concern most of the water utilities are compliance cost and treatment technologies. There are very few, if any, water utilities that are treating water with the objective of removing arsenic to levels less than 2 {micro}g/L. Some technologies such as reverse osmosis are capable of removing arsenic to a very low level, however, there is no data available due to the analytical limitation. All these information are critical to the development of treatment technologies and compliance cost.

  5. Enhanced adsorption of arsenic through the oxidative treatment of reduced aquifer solids.

    Science.gov (United States)

    Huling, Jenna R; Huling, Scott G; Ludwig, Ralph

    2017-10-15

    Arsenic (As) contamination in drinking water is an epidemic in many areas of the world, especially Eastern Asian countries. Developing affordable and efficient procedures to remove arsenic from drinking water is critical to protect human health. In this study, the oxidation of aquifer solids through the use of sodium permanganate (NaMnO4), hydrogen peroxide (H2O2), and exposure to air, enhanced the adsorption of arsenic to the aquifer material resulting in treatment of the water. NaMnO4 was more effective than H2O2. NaMnO4 was tested at different loading rates (0.5, 1.5, 2.4, 3.4, and 4.9 g NaMnO4/kg aquifer material), and after 30 days contact time, arsenic removal ([As+3]INITIAL = 610 μg/L) was 77%, 88%, 93%, 95%, 97%, respectively, relative to un-oxidized aquifer material. Arsenic removal increased with increasing contact time (30, 60, 90 days) suggesting removal was not reversible under the conditions of these experiments. Oxidative treatment by exposing the aquifer solids to air for 68 days resulted in >99% removal of Arsenic ([As+3]INITIAL = 550 μg/L). Less arsenic removal (38.2%) was measured in the un-oxidized aquifer material. In-situ oxidation of aquifer materials using NaMnO4, or ex-situ oxidation of aquifer materials through exposure to air could be effective in the removal of arsenic in ground water and a potential treatment method to protect human health. Published by Elsevier Ltd.

  6. 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

  7. Arsenic trioxide-mediated oxidative stress and genotoxicity in human hepatocellular carcinoma cells.

    Science.gov (United States)

    Alarifi, Saud; Ali, Daoud; Alkahtani, Saad; Siddiqui, Maqsood A; Ali, Bahy A

    2013-01-01

    Arsenic is a ubiquitous environmental toxicant, and abnormalities of the skin, lung, kidney, and liver are the most common outcomes of long-term arsenic exposure. This study was designed to investigate the possible mechanisms of genotoxicity induced by arsenic trioxide in human hepatocellular carcinoma cells. A mild cytotoxic response of arsenic trioxide was observed in human hepatocellular carcinoma cells, as evident by (3-(4,5-dimethyl thiazol-2-yl)-2, 5-diphenyl tetrazolium bromide) and lactate dehydrogenase assays after 24 and 48 hours of exposure. Arsenic trioxide elicited a significant (P hepatocellular carcinoma cells exposed to arsenic trioxide. The results demonstrate that arsenic trioxide induces apoptosis and genotoxicity in human hepatocellular carcinoma cells through reactive oxygen species and oxidative stress.

  8. 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 .

  9. Vascular Disrupting Agent Arsenic Trioxide Enhances Thermoradiotherapy of Solid Tumors

    Directory of Open Access Journals (Sweden)

    Robert J. Griffin

    2012-01-01

    Full Text Available Our previous studies demonstrated arsenic trioxide- (ATO- induced selective tumor vascular disruption and augmentation of thermal or radiotherapy effect against solid tumors. These results suggested that a trimodality approach of radiation, ATO, and local hyperthermia may have potent therapeutic efficacy against solid tumors. Here, we report the antitumor effect of hypofractionated radiation followed by ATO administration and local 42.5 °C hyperthermia and the effects of cisplatin and thermoradiotherapy. We found that the therapeutic efficacy of ATO-based thermoradiotherapy was equal or greater than that of cisplatin-based thermoradiotherapy, and marked evidence of in vivo apoptosis and tumor necrosis were observed in ATO-treated tumors. We conclude that ATO-based thermoradiotherapy is a powerful means to control tumor growth by using vascular disruption to augment the effects of thermal and radiation therapy.

  10. Chronic arsenic trioxide exposure leads to enhanced aggressiveness via Met oncogene addiction in cancer cells.

    Science.gov (United States)

    Kryeziu, Kushtrim; Pirker, Christine; Englinger, Bernhard; van Schoonhoven, Sushilla; Spitzwieser, Melanie; Mohr, Thomas; Körner, Wilfried; Weinmüllner, Regina; Tav, Koray; Grillari, Johannes; Cichna-Markl, Margit; Berger, Walter; Heffeter, Petra

    2016-05-10

    As an environmental poison, arsenic is responsible for many cancer deaths. Paradoxically, arsenic trioxide (ATO) presents also a powerful therapy used to treat refractory acute promyelocytic leukemia (APL) and is intensively investigated for treatment of other cancer types. Noteworthy, cancer therapy is frequently hampered by drug resistance, which is also often associated with enhancement of tumor aggressiveness. In this study, we analyzed ATO-selected cancer cells (A2780ATO) for the mechanisms underlying their enhanced tumorigenicity and aggressiveness. These cells were characterized by enhanced proliferation and spheroid growth as well as increased tumorigenicity of xenografts in SCID mice. Noteworthy, subsequent studies revealed that overexpression of Met receptor was the underlying oncogenic driver of these effects, as A2780ATO cells were characterized by collateral sensitivity against Met inhibitors. This finding was also confirmed by array comparative genomic hybridization (array CGH) and whole genome gene expression arrays, which revealed that Met overexpression by chronic ATO exposure was based on the transcriptional regulation via activation of AP-1. Finally, it was shown that treatment with the Met inhibitor crizotinib was also effective against A2780ATO cell xenografts in vivo, indicating that targeting of Met presents a promising strategy for the treatment of Met-overexpressing tumors after either arsenic exposure or failure to ATO treatment.

  11. Biochar increases arsenic release from an anaerobic paddy soil due to enhanced microbial reduction of iron and arsenic.

    Science.gov (United States)

    Wang, Ning; Xue, Xi-Mei; Juhasz, Albert L; Chang, Zhi-Zhou; Li, Hong-Bo

    2017-01-01

    Previous studies have shown that biochar enhances microbial reduction of iron (Fe) oxyhydroxide under anaerobic incubation. However, there is a lack of data on its influence on arsenic (As) release from As-contaminated paddy soils. In this study, paddy soil slurries (120 mg As kg(-1)) were incubated under anaerobic conditions for 60 days with and without the addition of biochar (3%, w/w) prepared from rice straw at 500 °C. Arsenic release, Fe reduction, and As fractionation were determined at 1, 10, 20, 30, and 60 d, while Illumina sequencing and real-time PCR were used to characterize changes in soil microbial community structure and As transformation function genes. During the first month of incubation, As released into soil solution increased sharply from 27.9 and 55.9 to 486 and 630 μg kg(-1) in unamended and biochar amended slurries, with inorganic trivalent As (As(III)) being the dominant specie (52.7-91.0% of total As). Compared to unamended slurries, biochar addition increased As and ferrous ion (Fe(2+)) concentrations in soil solution but decreased soil As concentration in the amorphous Fe/Al oxide fraction (F3). Difference in released As between biochar and unamended treatments (ΔAs) increased with incubation time, showing strong linear relationships (R(2) = 0.23-0.33) with ΔFe(2+) and ΔF3, confirming increased As release due to enhanced Fe reduction. Biochar addition increased the abundance of Fe reducing bacteria such as Clostridum (27.3% vs. 22.7%), Bacillus (3.34% vs. 2.39%), and Caloramator (4.46% vs. 3.88%). In addition, copy numbers in biochar amended slurries of respiratory As reducing (arrA) and detoxifying reducing genes (arsC) increased 19.0 and 1.70 fold, suggesting microbial reduction of pentavalent As (As(V)) adsorbed on Fe oxides to As(III), further contributing to increased As release. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. 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

  13. 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.

  14. Arsenic induces functional re-expression of estrogen receptor α by demethylation of DNA in estrogen receptor-negative human breast cancer.

    Science.gov (United States)

    Du, Juan; Zhou, Nannan; Liu, Hongxia; Jiang, Fei; Wang, Yubang; Hu, Chunyan; Qi, Hong; Zhong, Caiyun; Wang, Xinru; Li, Zhong

    2012-01-01

    Estrogen receptor α (ERα) is a marker predictive for response of breast cancers to endocrine therapy. About 30% of breast cancers, however, are hormone- independent because of lack of ERα expression. New strategies are needed for re-expression of ERα and sensitization of ER-negative breast cancer cells to selective ER modulators. The present report shows that arsenic trioxide induces reactivated ERα, providing a target for therapy with ER antagonists. Exposure of ER-negative breast cancer cells to arsenic trioxide leads to re-expression of ERα mRNA and functional ERα protein in in vitro and in vivo. Luciferase reporter gene assays and 3-(4,5-dimethylthiazol-2-yl)- 5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assays show that, upon exposure to arsenic trioxide, formerly unresponsive, ER-negative MDA-MB-231 breast cancer cells become responsive to ER antagonists, 4-hydroxytamoxifen and ICI 182,780. Furthermore, methylation- specific PCR and bisulfite-sequencing PCR assays show that arsenic trioxide induces partial demethylation of the ERα promoter. A methyl donor, S-adenosylmethionine (SAM), reduces the degree of arsenic trioxide-induced re-expression of ERα and demethylation. Moreover, Western blot and ChIP assays show that arsenic trioxide represses expression of DNMT1 and DNMT3a along with partial dissociation of DNMT1 from the ERα promoter. Thus, arsenic trioxide exhibits a previously undefined function which induces re-expression ERα in ER-negative breast cancer cells through demethylation of the ERα promoter. These findings could provide important information regarding the application of therapeutic agents targeting epigenetic changes in breast cancers and potential implication of arsenic trioxide as a new drug for the treatment of ER-negative human breast cancer.

  15. Arsenic induces functional re-expression of estrogen receptor α by demethylation of DNA in estrogen receptor-negative human breast cancer.

    Directory of Open Access Journals (Sweden)

    Juan Du

    Full Text Available Estrogen receptor α (ERα is a marker predictive for response of breast cancers to endocrine therapy. About 30% of breast cancers, however, are hormone- independent because of lack of ERα expression. New strategies are needed for re-expression of ERα and sensitization of ER-negative breast cancer cells to selective ER modulators. The present report shows that arsenic trioxide induces reactivated ERα, providing a target for therapy with ER antagonists. Exposure of ER-negative breast cancer cells to arsenic trioxide leads to re-expression of ERα mRNA and functional ERα protein in in vitro and in vivo. Luciferase reporter gene assays and 3-(4,5-dimethylthiazol-2-yl- 5-(3-carboxymethoxyphenyl-2-(4-sulfophenyl-2H-tetrazolium (MTS assays show that, upon exposure to arsenic trioxide, formerly unresponsive, ER-negative MDA-MB-231 breast cancer cells become responsive to ER antagonists, 4-hydroxytamoxifen and ICI 182,780. Furthermore, methylation- specific PCR and bisulfite-sequencing PCR assays show that arsenic trioxide induces partial demethylation of the ERα promoter. A methyl donor, S-adenosylmethionine (SAM, reduces the degree of arsenic trioxide-induced re-expression of ERα and demethylation. Moreover, Western blot and ChIP assays show that arsenic trioxide represses expression of DNMT1 and DNMT3a along with partial dissociation of DNMT1 from the ERα promoter. Thus, arsenic trioxide exhibits a previously undefined function which induces re-expression ERα in ER-negative breast cancer cells through demethylation of the ERα promoter. These findings could provide important information regarding the application of therapeutic agents targeting epigenetic changes in breast cancers and potential implication of arsenic trioxide as a new drug for the treatment of ER-negative human breast cancer.

  16. 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.

  17. Biomineralization of Arsenate to Arsenic Sulfides is Greatly Enhanced at Mildly Acidic Conditions

    Science.gov (United States)

    Rodriguez-Freire, Lucia; Sierra-Alvarez, Reyes; Root, Robert; Chorover, Jon; Field, James A.

    2014-01-01

    Arsenic (As) is an important water contaminant due to its high toxicity and widespread occurrence. Arsenic-sulfide minerals (ASM) are formed during microbial reduction of arsenate (AsV) and sulfate (SO42−). The objective of this research is to study the effect of the pH on the removal of As due to the formation of ASM in an iron-poor system. A series of batch experiments was used to study the reduction of SO42− and AsV by an anaerobic biofilm mixed culture in a range of pH conditions (6.1–7.2), using ethanol as the electron donor. Total soluble concentrations and speciation of S and As were monitored. Solid phase speciation of arsenic was characterized by x-ray adsorption spectroscopy (XAS). A marked decrease of the total aqueous concentrations of As and S was observed in the inoculated treatments amended with ethanol, but not in the non-inoculated controls, indicating that the As-removal was biologically mediated. The pH dramatically affected the extent and rate of As removal, as well as the stoichiometric composition of the precipitate. The amount of As removed was 2-fold higher and the rate of the As removal was up to 17-fold greater at pH 6.1 than at pH 7.2. Stoichiometric analysis and XAS results confirmed the precipitate was composed of a mixture of orpiment and realgar, and the proportion of orpiment in the sample increased with increasing pH. The results taken as a whole suggest that ASM formation is greatly enhanced at mildly acidic pH conditions. PMID:25222328

  18. Arsenic inhibits the adipogenic differentiation of mesenchymal stem cells by down-regulating peroxisome proliferator-activated receptor gamma and CCAAT enhancer-binding proteins.

    Science.gov (United States)

    Yadav, Santosh; Anbalagan, Muralidharan; Shi, Yongli; Wang, Feng; Wang, He

    2013-02-01

    Arsenic remains a top environmental concern in the United States as well as worldwide because of its global existence and serious health impacts. Apoptotic effect of arsenic in human mesenchymal stem cells (hMSCs) has been identified in our previous study; the effects of arsenic on hMSCs remain largely unknown. Here, we report that arsenic inhibits the adipogenic differentiation of human mesenchymal stem cells (hMSCs). Arsenic reduced the formation of lipid droplets and the expression of adipogenesis-related proteins, such as CCAAT enhancer binding protein-(C/EBPs), peroxisome proliferator-activated receptor-gamma (PPAR-γ), and adipocyte fatty acid-binding protein aP2 (aP2). Arsenic mediates this process by sustaining PPAR-γ activity. In addition, inhibition of PPAR-γ activity with T0070907 and up-regulation with its agonist troglitazone, showed the direct association of PPAR-γ and arsenic-mediated inhibition of differentiating hMSCs. Taken together, these results indicate that arsenic inhibits adipogenic differentiation through PPAR-γ pathway and suggest a novel inhibitory effect of arsenic on adipogenic differentiation in hMSCs. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  19. Electrolyte conditioning-enhanced electrokinetic remediation of arsenic-contaminated mine tailing.

    Science.gov (United States)

    Baek, Kitae; Kim, Do-Hyung; Park, Sung-Woo; Ryu, Byung-Gon; Bajargal, Tserennyam; Yang, Jung-Seok

    2009-01-15

    Feasibility of electrolyte conditioning with strong acidic or alkaline solution on electrokinetic remediation of arsenic-contaminated mine tailing was investigated in the laboratory. The mine tailing contained calcium oxide of more than 50%. At alkaline condition, arsenic was precipitated with calcium, and formed calcium arsenate which is very stable solid. Catholyte conditioning with strong acidic solution and anolyte conditioning with strong alkaline solution showed similar efficiency to remove arsenic. At 4mAcm(-2) of current density, the removal efficiency of arsenic was 62% after 28 days operation with catholyte conditioning with 0.1M nitric acid.

  20. 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

  1. 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.

  2. Arsenic Remediation Enhancement Through Chemical Additions to Pump and Treat Operations

    Science.gov (United States)

    Wovkulich, K.; Mailloux, B. J.; Stute, M.; Simpson, H. J.; Keimowitz, A. R.; Powell, A.; Lacko, A.; Chillrud, S. N.

    2008-12-01

    Arsenic is a contaminant found at more than 500 US Superfund sites. Since pump and treat technologies are widely used for remediation of contaminated groundwater, increasing the efficiency of contaminant removal at such sites should allow limited financial resources to clean up more sites. The Vineland Chemical Company Superfund site is extensively contaminated with arsenic after waste arsenic salts were stored and disposed of improperly for much of the company's 44 year manufacturing lifetime. Despite approximately eight years of pump and treat remediation, arsenic concentrations in the recovery wells can still be greater than 1000 ppb. The arsenic concentrations in the groundwater remain high because of slow desorption of arsenic from contaminated aquifer solids. Extrapolation of laboratory column experiments suggest that continuing the current groundwater remediation practice based on flushing ambient groundwater through the system may require on the order of hundreds of years to clean the site. However, chemical additions of phosphate or oxalic acid into the aquifer could decrease the remediation time scale substantially. Laboratory results from a soil column experiment using input of 10 mM oxalic acid suggest that site clean up of groundwater could be decreased to as little as four years. Pilot scale forced gradient field experiments will help establish whether chemical additions can be effective for increasing arsenic mobilization from aquifer solids and thus substantially decrease pump and treat clean up time.

  3. 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.

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

    Science.gov (United States)

    Thompson, Benjamin C; Halliday, Gary M; Damian, Diona L

    2015-01-01

    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.

  5. Trolox enhances the anti-lymphoma effects of arsenic trioxide, while protecting against liver toxicity.

    Science.gov (United States)

    Diaz, Z; Laurenzana, A; Mann, K K; Bismar, T A; Schipper, H M; Miller, W H

    2007-10-01

    Arsenic trioxide (As2O3) is an effective therapy in acute promyelocytic leukemia (APL), but its use in other malignancies is limited by the higher concentrations required to induce apoptosis. We have reported that trolox, an analogue of alpha-tocopherol, increases As2O3-mediated apoptosis in a variety of APL, myeloma and breast cancer cell lines, while non-malignant cells may be protected. In the present study, we extended previous results to show that trolox increases As2O3-mediated apoptosis in the P388 lymphoma cell line in vitro, as evidenced by decrease of mitochondrial membrane potential and release of cytochrome c. We then sought to determine whether this combination can enhance antitumor effects while protecting normal cells in vivo. In BDF1 mice, trolox treatment decreased As2O3-induced hepatomegaly, markers of oxidative stress and hepatocellular damage. In P388 tumor-bearing mice, As2O3 treatment prolonged survival, and the addition of trolox provided a further significant increase in lifespan. In addition, the combination of As2O3 and trolox inhibited metastatic spread, and protected the tumor-bearing mice from As2O3 liver toxicity. Our results suggest, for the first time, that trolox might prevent some of the clinical manifestations of As2O3-related toxicity while increasing its pro-apoptotic capacity and clinical efficacy in hematological malignancies.

  6. Enhancement of the upper critical field in codoped iron-arsenic high-temperature superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Rosner, H.; Nicklas, M.; Schnelle, W.; Leithe-Jasper, A. [MPI CPfS Dresden (Germany); Wosnitza, J. [HLD Dresden-Rossendorf (Germany); Weickert, F. [MPI CPfS Dresden (Germany); LANL, Los Alamos, NM (United States)

    2012-07-01

    We present the first study of codoped iron-arsenide superconductors of the 122 family (Sr/Ba){sub 1-x}K{sub x}Fe{sub 2-y}Co{sub y}As{sub 2} with the purpose to increase the upper critical field H{sub c2} compared to single doped Sr/BaFe{sub 2}As{sub 2} materials. H{sub c2} was investigated by measuring the magnetoresistance in high pulsed magnetic fields up to 64 T. We find, that H{sub c2} extrapolated to T=0 is indeed enhanced significantly to 90 T for polycrystalline samples of Ba{sub 0.55}K{sub 0.45}Fe{sub 1.95}Co{sub 0.05}As{sub 2} compared to 75 T for Ba{sub 0.55}K{sub 0.45}Fe{sub 2}As{sub 2} and BaFe{sub 1.8}Co{sub 0.2}As{sub 2} single crystals. Codoping thus is a promising way for the systematic optimization of iron-arsenic based superconductors for magnetic-field and high-current applications.

  7. Phosphate enhanced abiotic and biotic arsenic mobilization in the wetland rhizosphere.

    Science.gov (United States)

    Zhang, Zheyun; Moon, Hee Sun; Myneni, Satish C B; Jaffé, Peter R

    2017-11-01

    Although abiotic process of competitive sorption between phosphate (P) and arsenate (As(V)), especially onto iron oxides, are well understood, P-mediated biotic processes of Fe and As redox transformation contributing to As mobilization and speciation in wetlands remain poorly defined. To gain new insights into the effects of P on As mobility, speciation, and bioavailability in wetlands, well-controlled greenhouse experiments were conducted. As expected, increased P levels contributed to more As desorption, but more interestingly the interactions between P and wetland plants played a synergistic role in the microbially-mediated As mobilization and enhanced As uptake by plants. High levels of P promoted plant growth and the exudation of labile organic carbon from roots, enhancing the growth of heterotrophic bacteria, including As and Fe reducers. This in turn resulted in both, more As desorption into solution due to reductive iron dissolution, and a higher fraction of the dissolved As in the form of As(III) due to the higher number of As(V) reducers. Consistent with the dissolved As results, arsenic-XANES spectra from solid medium samples demonstrated that more As was sequestered in the rhizosphere as As(III) in the presence of high P levels than for low P levels. Hence, increased P loading to wetlands stimulates both abiotic and biotic processes in the wetland rhizosphere, resulting in more As mobilization, more As reduction, as well as more As uptake by plants. These interactions are important to be taken into account in As fate and transport models in wetlands and management of wetlands containing As. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Enhancing the efficacy of cisplatin in ovarian cancer treatment – could arsenic have a role

    Directory of Open Access Journals (Sweden)

    Helm C William

    2009-01-01

    Full Text Available Abstract Ovarian cancer affects more than 200,000 women each year around the world. Most women are not diagnosed until the disease has already metastasized from the ovaries with a resultant poor prognosis. Ovarian cancer is associated with an overall 5 year survival of little more than 50%. The mainstay of front-line therapy is cytoreductive surgery followed by chemotherapy. Traditionally, this has been by the intravenous route only but there is more interest in the delivery of intraperitoneal chemotherapy utilizing the pharmaco-therapeutic advantage of the peritoneal barrier. Despite three large, randomized clinical trials comparing intravenous with intraperitoneal chemotherapy showing improved outcomes for those receiving at least part of their chemotherapy by the intraperitoneal route. Cisplatin has been the most active drug for the treatment of ovarian cancer for the last 4 decades and the prognosis for women with ovarian cancer can be defined by the tumor response to cisplatin. Those whose tumors are innately platinum-resistant at the time of initial treatment have a very poor prognosis. Although the majority of patients with ovarian cancer respond to front-line platinum combination chemotherapy the majority will develop disease that becomes resistant to cisplatin and will ultimately succumb to the disease. Improving the efficacy of cisplatin could have a major impact in the fight against this disease. Arsenite is an exciting agent that not only has inherent single-agent tumoricidal activity against ovarian cancer cell lines but also multiple biochemical interactions that may enhance the cytotoxicity of cisplatin including inhibition of deoxyribose nucleic acid (DNA repair. In vitro studies suggest that arsenite may enhance the activity of cisplatin in other cell types. Arsenic trioxide is already used clinically to treat acute promyelocytic leukemia demonstrating its safety profile. Further research in ovarian cancer is warranted to define

  9. Fate of arsenic before and after chemical-enhanced washing of an arsenic-containing soil in Hong Kong.

    Science.gov (United States)

    Beiyuan, Jingzi; Li, Jiang-Shan; Tsang, Daniel C W; Wang, Lei; Poon, Chi Sun; Li, Xiang-Dong; Fendorf, Scott

    2017-12-01

    This study evaluated the feasibility of 2-h chemical-enhanced washing of As-containing soil resulting from geogenic sources in Hong Kong and the fate of As before and after remediation. The soil morphology and As speciation in soil was elucidated by scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray diffractometer, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy. Integrated analysis of the results suggests that the As (>90%) resides predominantly as arsenate bound to ferric iron oxides, with a minor contribution (containing soil by containment or physical encapsulation may be considered before land development. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. 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

  11. Arsenic trioxide-mediated oxidative stress and genotoxicity in human hepatocellular carcinoma cells

    Directory of Open Access Journals (Sweden)

    Alarifi S

    2013-02-01

    Full Text Available Saud Alarifi,1 Daoud Ali,1 Saad Alkahtani,1 Maqsood A Siddiqui,2 Bahy A Ali2,31Cell and Molecular Laboratory, Department of Zoology, Faculty of Science, King Saud University, Riyadh, Saudi Arabia; 2DNA Research Chair, Department of Zoology, Faculty of Science, King Saud University, Riyadh, Saudi Arabia; 3Genetic Engineering & Biotechnology Research Institute City for Scientific Research and Technology Applications, Alexandria, EgyptBackground: Arsenic is a ubiquitous environmental toxicant, and abnormalities of the skin, lung, kidney, and liver are the most common outcomes of long-term arsenic exposure. This study was designed to investigate the possible mechanisms of genotoxicity induced by arsenic trioxide in human hepatocellular carcinoma cells.Methods and results: A mild cytotoxic response of arsenic trioxide was observed in human hepatocellular carcinoma cells, as evident by (3-(4,5-dimethyl thiazol-2-yl-2, 5-diphenyl tetrazolium bromide and lactate dehydrogenase assays after 24 and 48 hours of exposure. Arsenic trioxide elicited a significant (P < 0.01 reduction in glutathione (15.67% and 26.52%, with a concomitant increase in malondialdehyde level (67.80% and 72.25%; P < 0.01, superoxide dismutase (76.42% and 81.09%; P < 0.01, catalase (73.33% and 76.47%; P < 0.01, and reactive oxygen species generation (44.04% and 56.14%; P < 0.01 after 24 and 48 hours of exposure, respectively. Statistically significant (P < 0.01 induction of DNA damage was observed by the comet assay in cells exposed to arsenic trioxide. It was also observed that apoptosis occurred through activation of caspase-3 and phosphatidylserine externalization in human hepatocellular carcinoma cells exposed to arsenic trioxide.Conclusion: The results demonstrate that arsenic trioxide induces apoptosis and genotoxicity in human hepatocellular carcinoma cells through reactive oxygen species and oxidative stress.Keywords: arsenic trioxide, DNA damage, hepatocellular carcinoma

  12. Augmentation of arsenic enhances lipid yield and defense responses in alga Nannochloropsis sp.

    Science.gov (United States)

    Upadhyay, A K; Mandotra, S K; Kumar, N; Singh, N K; Singh, Lav; Rai, U N

    2016-12-01

    The present study was conducted with microalga Nannochloropsis sp. to evaluate its tolerance responses and biofuel perspectives under different arsenic regime (0-1000μM As(III)). Results showed that optimal biomass (61.00±3.72mg/L/d) and lipid productivity (20.27mg/L/d) were obtained in culture treated with 100μM As(III) in comparison to other treatments. In addition, fatty acid profile of alga was in accordance with European biodiesel standards (EN 14214), which reflects good oxidative stability of oil. High antioxidants viz., ascorbic acid, GSH and cysteine tolerance responses as well as lipid yield at 100μM As(III), opens a new insight in the field of algal biology. Thus, microalgae Nannochloropsis sp. may be employ in remediation as well as biodiesel production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Enhanced adsorption of trivalent arsenic from water by functionalized diatom silica shells.

    Science.gov (United States)

    Zhang, Jianying; Ding, Tengda; Zhang, Zhijian; Xu, Liping; Zhang, Chunlong

    2015-01-01

    The potential of porous diatom silica shells as a naturally abundant low-cost sorbent for the removal of arsenic in aqueous solutions was investigated in a batch study. The objective of this work was to chemically modify the silica shells of a diatom Melosira sp. with bifunctional (thiol and amino) groups to effectively remove arsenic in its toxic As(III) form (arsenite) predominant in the aquatic environment. Sorption experiments with this novel sorbent were conducted under varying conditions of pH, time, dosage, and As(III) concentration. A maximum adsorption capacity of 10.99 mg g-1 was achieved within 26 h for a solution containing 12 mg L-1 As(III) at pH 4 and sorbent dosage of 2 g L-1. The functionalized diatom silica shells had a surface morphological change which was accompanied by increased pore size at the expense of reduced specific surface area and total pore volume. As(III) adsorption was best fitted with the Langmuir-Freundlich model, and the adsorption kinetic data using pore surface diffusion model showed that both the external (film) and internal (intraparticle) diffusion can be rate-determining for As(III) adsorption. Fourier transform infrared spectroscopy (FTIR) indicated that the thiol and amino groups potentially responsible for As(III) adsorption were grafted on the surface of diatom silica shells. X-ray photoelectron spectroscopy (XPS) further verified that this unique sorbent proceeded via a chemisorption mechanism through the exchange between oxygen-containing groups of neutral As(III) and thiol groups, and through the surface complexation between As(III) and protonated nitrogen and hydroxyl groups. Results indicate that this functionalized bioadsorbent with a high As(III) adsorption capacity holds promise for the treatment of As(III) containing wastewater.

  14. Enhanced adsorption of trivalent arsenic from water by functionalized diatom silica shells.

    Directory of Open Access Journals (Sweden)

    Jianying Zhang

    Full Text Available The potential of porous diatom silica shells as a naturally abundant low-cost sorbent for the removal of arsenic in aqueous solutions was investigated in a batch study. The objective of this work was to chemically modify the silica shells of a diatom Melosira sp. with bifunctional (thiol and amino groups to effectively remove arsenic in its toxic As(III form (arsenite predominant in the aquatic environment. Sorption experiments with this novel sorbent were conducted under varying conditions of pH, time, dosage, and As(III concentration. A maximum adsorption capacity of 10.99 mg g-1 was achieved within 26 h for a solution containing 12 mg L-1 As(III at pH 4 and sorbent dosage of 2 g L-1. The functionalized diatom silica shells had a surface morphological change which was accompanied by increased pore size at the expense of reduced specific surface area and total pore volume. As(III adsorption was best fitted with the Langmuir-Freundlich model, and the adsorption kinetic data using pore surface diffusion model showed that both the external (film and internal (intraparticle diffusion can be rate-determining for As(III adsorption. Fourier transform infrared spectroscopy (FTIR indicated that the thiol and amino groups potentially responsible for As(III adsorption were grafted on the surface of diatom silica shells. X-ray photoelectron spectroscopy (XPS further verified that this unique sorbent proceeded via a chemisorption mechanism through the exchange between oxygen-containing groups of neutral As(III and thiol groups, and through the surface complexation between As(III and protonated nitrogen and hydroxyl groups. Results indicate that this functionalized bioadsorbent with a high As(III adsorption capacity holds promise for the treatment of As(III containing wastewater.

  15. Enhanced suppression of tumor growth by concomitant treatment of human lung cancer cells with suberoylanilide hydroxamic acid and arsenic trioxide

    Energy Technology Data Exchange (ETDEWEB)

    Chien, Chia-Wen [Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 11490, Taiwan (China); Yao, Ju-Hsien [Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan (China); Chang, Shih-Yu [Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Lee, Pei-Chih [Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan (China); Lee, Te-Chang, E-mail: bmtcl@ibms.sinica.edu.tw [Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan (China)

    2011-11-15

    The efficacy of arsenic trioxide (ATO) against acute promyelocytic leukemia (APL) and relapsed APL has been well documented. ATO may cause DNA damage by generating reactive oxygen intermediates. Suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, modulates gene and protein expression via histone-dependent or -independent pathways that may result in chromatin decondensation, cell cycle arrest, differentiation, and apoptosis. We investigated whether ATO and SAHA act synergistically to enhance the death of cancer cells. Our current findings showed that combined treatment with ATO and SAHA resulted in enhanced suppression of non-small-cell lung carcinoma in vitro in H1299 cells and in vivo in a xenograft mouse model. Flow cytometric analysis of annexin V+ cells showed that apoptotic cell death was significantly enhanced after combined treatment with ATO and SAHA. At the doses used, ATO did not interfere with cell cycle progression, but SAHA induced p21 expression and led to G1 arrest. A Comet assay demonstrated that ATO, but not SAHA, induced DNA strand breaks in H1299 cells; however, co-treatment with SAHA significantly increased ATO-induced DNA damage. Moreover, SAHA enhanced acetylation of histone H3 and sensitized genomic DNA to DNase I digestion. Our results suggest that SAHA may cause chromatin relaxation and increase cellular susceptibility to ATO-induced DNA damage. Combined administration of SAHA and ATO may be an effective approach to the treatment of lung cancer. -- Highlights: Black-Right-Pointing-Pointer ATO and SAHA are therapeutic agents with different action modes. Black-Right-Pointing-Pointer Combination of ATO and SAHA synergistically inhibits tumor cell growth. Black-Right-Pointing-Pointer SAHA loosens chromatin structure resulting in increased sensitivity to DNase I. Black-Right-Pointing-Pointer ATO-induced DNA damage and apoptosis are enhanced by co-treatment with SAHA.

  16. Arsenic Detoxification by Geobacter Species.

    Science.gov (United States)

    Dang, Yan; Walker, David J F; Vautour, Kaitlin E; Dixon, Steven; Holmes, Dawn E

    2017-02-15

    Insight into the mechanisms for arsenic detoxification by Geobacter species is expected to improve the understanding of global cycling of arsenic in iron-rich subsurface sedimentary environments. Analysis of 14 different Geobacter genomes showed that all of these species have genes coding for an arsenic detoxification system (ars operon), and several have genes required for arsenic respiration (arr operon) and methylation (arsM). Genes encoding four arsenic repressor-like proteins were detected in the genome of G. sulfurreducens; however, only one (ArsR1) regulated transcription of the ars operon. Elimination of arsR1 from the G. sulfurreducens chromosome resulted in enhanced transcription of genes coding for the arsenic efflux pump (Acr3) and arsenate reductase (ArsC). When the gene coding for Acr3 was deleted, cells were not able to grow in the presence of either the oxidized or reduced form of arsenic, while arsC deletion mutants could grow in the presence of arsenite but not arsenate. These studies shed light on how Geobacter influences arsenic mobility in anoxic sediments and may help us develop methods to remediate arsenic contamination in the subsurface. This study examines arsenic transformation mechanisms utilized by Geobacter, a genus of iron-reducing bacteria that are predominant in many anoxic iron-rich subsurface environments. Geobacter species play a major role in microbially mediated arsenic release from metal hydroxides in the subsurface. This release raises arsenic concentrations in drinking water to levels that are high enough to cause major health problems. Therefore, information obtained from studies of Geobacter should shed light on arsenic cycling in iron-rich subsurface sedimentary environments, which may help reduce arsenic-associated illnesses. These studies should also help in the development of biosensors that can be used to detect arsenic contaminants in anoxic subsurface environments. We examined 14 different Geobacter genomes and found

  17. Sulforaphane synergistically enhances the cytotoxicity of arsenic trioxide in multiple myeloma cells via stress-mediated pathways

    Science.gov (United States)

    DOUDICAN, NICOLE A.; WEN, SHIH YA; MAZUMDER, AMITABHA; ORLOW, SETH J.

    2012-01-01

    Persistent paraprotein production in plasma cells necessitates a highly developed rough endoplasmic reticulum (ER) that is unusually susceptible to perturbations in protein synthesis. This biology is believed to account for the exquisite sensitivity of multiple myeloma (MM) to the proteasomal inhibitor bortezomib (BTZ). Despite remarkable response rates to BTZ in MM, BTZ carries the potential for serious side-effects and development of resistance. We, therefore, sought to identify therapeutic combinations that effectively disrupt proteostasis in order to provide new potential treatments for MM. We found that sulforaphane, a dietary isothiocyanate found in cruciferous vegetables, inhibits TNFα-induced Iκβ proteasomal degradation in a manner similar to BTZ. Like BTZ, sulforaphane synergistically enhances the cytotoxicity of arsenic trioxide (ATO), an agent with clinical activity in MM. ATO and sulforaphane co-treatment augmented apoptotic induction as demonstrated by cleavage of caspase-3, -4 and PARP. The enhanced apoptotic response was dependent upon production of reactive oxygen species (ROS) as demonstrated by glutathione depletion and partial inhibition of the apoptotic cascade after pretreatment with the radical scavenger N-acetyl-cysteine (NAC). Combination treatment resulted in enhanced ER stress signaling and activation of the unfolded protein response (UPR), indicative of perturbation of proteostasis. Specifically, combination treatment caused elevated expression of the molecular chaperone HSP90 (heat shock protein 90) along with increased PERK (protein kinase RNA-like endoplasmic reticulum kinase) and eIF2α phosphorylation and XBP1 (X-box binding protein 1) splicing, key indicators of UPR activation. Moreover, increased splicing of XBP1 was apparent upon combination treatment compared to treatment with either agent alone. Sulforaphane in combination with ATO effectively disrupts protein homeostasis through ROS generation and induction of ER stress to

  18. 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.

  19. Method of removing arsenic and other anionic contaminants from contaminated water using enhanced coagulation

    Science.gov (United States)

    Teter, David M.; Brady, Patrick V.; Krumhansl, James L.; Khandaker, Nadim R.

    2006-11-21

    An improved water decontamination process comprising contacting water containing anionic contaminants with an enhanced coagulant to form an enhanced floc, which more efficiently binds anionic species (e.g., arsenate, arsenite, chromate, fluoride, selenate, and borate, and combinations thereof) predominantly through the formation of surface complexes. The enhanced coagulant comprises a trivalent metal cation coagulant (e.g., ferric chloride or aluminum sulfate) mixed with a divalent metal cation modifier (e.g., copper sulfate or zinc sulfate).

  20. Trolox selectively enhances arsenic-mediated oxidative stress and apoptosis in APL and other malignant cell lines.

    Science.gov (United States)

    Diaz, Zuanel; Colombo, Myrian; Mann, Koren K; Su, Haixiang; Smith, Kamilah N; Bohle, D Scott; Schipper, Hyman M; Miller, Wilson H

    2005-02-01

    Although arsenic trioxide (As(2)O(3)) is an effective therapy in acute promyelocytic leukemia (APL), its use in other malignancies is limited by the toxicity of concentrations required to induce apoptosis in non-APL tumor cells. We looked for agents that would synergize with As(2)O(3) to induce apoptosis in malignant cells, but not in normal cells. We found that trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), a widely known antioxidant, enhances As(2)O(3)-mediated apoptosis in APL, myeloma, and breast cancer cells. Treatment with As(2)O(3) and trolox increased intracellular oxidative stress, as evidenced by heme oxygenase-1 (HO-1) protein levels, c-Jun terminal kinase (JNK) activation, and protein and lipid oxidation. The synergistic effects of trolox may be specific to As(2)O(3), as trolox does not add to toxicity induced by other chemotherapeutic drugs. We explored the mechanism of this synergy using electron paramagnetic resonance and observed the formation of trolox radicals when trolox was combined with As(2)O(3), but not with doxorubicin. Importantly, trolox protected nonmalignant cells from As(2)O(3)-mediated cytotoxicity. Our data provide the first evidence that trolox may extend the therapeutic spectrum of As(2)O(3). Furthermore, the combination of As(2)O(3) and trolox shows potential specificity for tumor cells, suggesting it may not increase the toxicity associated with As(2)O(3) monotherapy in vivo.

  1. Enhanced Removal of Arsenic and Antimony in the Mining Site by Calcined γ-Fe2O3/Layered Double Hydroxide Nanocomposite

    Science.gov (United States)

    Lee, Sang-Ho; Choi, Heechul; Kim, Kyoung-Woong

    2016-04-01

    Arsenic (As) and Antimony (Sb) have been recognized as harmful contaminants in aquatic environment due to its high toxicity and carcinogenicity. Especially, the contamination of arsenic in the mining areas is considered as a serious emerging environmental issue in Korea. Due to the hazardous effect of arsenic, the United States Environmental Protection Agency (US EPA) regulated maximum contamination level of arsenic to 10 μg/L in drinking water. The harmful effect on human health by excessive intake of antimony was also reported by previous studies, and severe contamination level (100 - 7,000 μg/L) of antimony reported in surface and groundwater of abandoned mining area in China and Slovakia. Therefore, US EPA regulated maximum contaminants level of antimony in drinking water to 6 μg/L. In order to remove anionic contaminants in drinking water, various type of nanomaterials have been developed. Layered double hydroxide (LDH) is the artificial anionic clay that is based on the layered structure of positively charged brucite-like layers with interlayers of anions. The LDH is one of the promising nanomaterials for the removal of anionic contaminants because it has high selectivity for arsenic, phosphate, chromium and antimony. However, the biggest problem of LDH for wastewater treatment is that the particles cannot be easily separated after the removal of contaminants. In this study, magnetic nanoparticles (γ-Fe2O3) supported LDH nanocomposite (γ-Fe2O3/LDH) was investigated to enhance magnetic particle recovery and removal efficiency for arsenic and antimony. The calcined γ-Fe2O3/LDH nanocomposites synthesized by co-precipitation method, and the crystallographic properties of maghemite (γ-Fe2O3) and layered structure of LDH were confirmed by X-ray diffraction. The nano-sized γ-Fe2O3 (30 to 50 nm) was stably attached on the surface of LDH (100 to 150 nm) and O1s spectrum by X-ray photoelectron spectroscopy (XPS) explained that there are both physical and

  2. 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.

  3. 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

  4. A novel nanoparticulate formulation of arsenic trioxide with enhanced therapeutic efficacy in a murine model of breast cancer.

    Science.gov (United States)

    Ahn, Richard W; Chen, Feng; Chen, Haimei; Stern, Stephan T; Clogston, Jeffrey D; Patri, Anil K; Raja, Meera R; Swindell, Elden P; Parimi, Vamsi; Cryns, Vincent L; O'Halloran, Thomas V

    2010-07-15

    The clinical success of arsenic trioxide (As(2)O(3)) in hematologic malignancies has not been replicated in solid tumors due to poor pharmacokinetics and dose-limiting toxicity. We have developed a novel nanoparticulate formulation of As(2)O(3) encapsulated in liposomal vesicles or "nanobins" [(NB(Ni,As)] to overcome these hurdles. We postulated that nanobin encapsulation of As(2)O(3) would improve its therapeutic index against clinically aggressive solid tumors, such as triple-negative breast carcinomas. The cytotoxicity of NB(Ni,As), the empty nanobin, and free As(2)O(3) was evaluated against a panel of human breast cancer cell lines. The plasma pharmacokinetics of NB(Ni,As) and free As(2)O(3) were compared in rats to measure drug exposure. In addition, the antitumor activity of these agents was evaluated in an orthotopic model of human triple-negative breast cancer. The NB(Ni,As) agent was much less cytotoxic in vitro than free As(2)O(3) against a panel of human breast cancer cell lines. In contrast, NB(Ni,As) dramatically potentiated the therapeutic efficacy of As(2)O(3) in vivo in an orthotopic model of triple-negative breast cancer. Reduced plasma clearance, enhanced tumor uptake, and induction of tumor cell apoptosis were observed for NB(Ni,As). Nanobin encapsulation of As(2)O(3) improves the pharmacokinetics and antitumor efficacy of this cytotoxic agent in vivo. Our findings demonstrate the therapeutic potential of this nanoscale agent and provide a foundation for future clinical studies in breast cancer and other solid tumors. Copyright 2010 AACR.

  5. Enhancement of arsenic adsorption during mineral transformation from siderite to goethite: mechanism and application.

    Science.gov (United States)

    Guo, Huaming; Ren, Yan; Liu, Qiong; Zhao, Kai; Li, Yuan

    2013-01-15

    Synthesized siderite was used to remove As(III) and As(V) from water solutions under anoxic conditions and oxic conditions. Results showed that As adsorption on synthetic siderite under anoxic conditions was around 10 mg/g calculated with Langmuir isotherm. However, the calculated As adsorption on synthetic siderite under oxic conditions ranged between 115 and 121 mg/g, which was around 11 times higher than that under anoxic conditions. It was found that 75% siderite was transformed into goethite during oxic adsorption. However, synthetic goethite had lower As adsorption capacity than siderite under oxic conditions, although its adsorption capacity was a little higher than siderite under anoxic conditions. It suggested that the coexistence of goethite and siderite bimineral during mineral transformation probably contributed to the robust adsorption capacity of siderite under oxic conditions. Results of extended X-ray absorption fine structure (EXAF) spectroscopy indicated both As(III) and As(V) formed inner-sphere complexes on the surface of As-treated solid regardless of substrates, including the bidentate binuclear corner-sharing ((2)C) complexes and the monodentate mononuclear corner-sharing ((1)V) complexes. Monodenate ((1)V) and bidentate ((2)C) complexes would be related to high As adsorption capacity of siderite under oxic conditions. It showed that more Fe atoms were coordinated with As atom in the monodentate complexes and the bidentate complexes of As(V)/As(III)-treated siderite under oxic conditions, in comparison with As(V)/As(III)-treated siderite under anoxic conditions and As(V)/As(III)-treated goethite. Calcinations of natural siderite resulting in the coexistence of goethite and siderite greatly increased As adsorption on the solid, which confirmed that the coexistence of bimineral during mineral transformation from siderite to goethite greatly enhanced As adsorption capacity of siderite adsorbent. The observation can be applied for modification of

  6. Nicotinamide Enhances Repair of Arsenic and Ultraviolet Radiation-Induced DNA Damage in HaCaT Keratinocytes and Ex Vivo Human Skin

    OpenAIRE

    Thompson, Benjamin C.; Halliday, Gary M.; Damian, Diona L.

    2015-01-01

    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 ...

  7. Arsenic bioleaching in medical realgar ore and arsenicbearing ...

    African Journals Online (AJOL)

    Oxidation of these two ores by sulfuric acid was insignificant, as maximum arsenic leaching ratios of realgar and arsenic-bearing refractory gold ore in the absence of any bacterium were only 2.8 and 11.2 %, respectively. Conclusion: Arsenic leaching ratio of realgar and refractory gold ore can be enhanced significantly in ...

  8. 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.

  9. 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.

  10. Arsenic Trioxide (ATO) cooperates with All Trans Retinoic Acid (ATRA) to enhance MAPK activation and differentiation in Human Myeloblastic Leukemia (HL-60) cells

    Science.gov (United States)

    Nayak, Satyaprakash; Shen, Miaoqing; Varner, Jeffrey D.; Yen, Andrew

    2016-01-01

    Arsenic trioxide (ATO) synergistically promotes retinoic acid (RA)-induced differentiation of HL-60 myeloblastic leukemia cells, a PML-RARα negative cell line. In PML-RARα positive myeloid leukemia cells, ATO is known to cause degradation of PML-RARα with subsequent induced myeloid differentiation. We find now that ATO by itself does not cause differentiation of the PML-RARα negative HL-60 cells, but enhances RA’s capability to cause differentiation. RA-induced differentiation of HL-60 cells is known to be propelled by an induced hyperactive/persistent MAPK signal. ATO augmented RA induced RAF/MEK/ERK axis signaling and expression of CD11b, an integrin receptor that is a myeloid differentiation marker. p47PHOX, a component of the respiratory burst machinery and inducible oxidative metabolism, functional differentiation marker were also enhanced. However, ATO did not enhance RA-induced CD38 expression, an early cell surface differentiation marker. ATO enhanced RA-induced population growth retardation without evidence of apoptosis or an enhanced G1/0 growth arrest. But compared to RA, ATO plus RA showed reduced pAKT, suggesting that an overall biosynthetic/metabolic retardation was seminal to the apparent enhanced growth retardation due to ATO. In sum, our results indicate that ATO can augment action of RA in causing differentiation of myeloid leukemia cells through promoting MAPK signaling and independent of PML-RARα. PMID:20615082

  11. 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, ...

  12. Arsenic metabolism and one-carbon metabolism at low-moderate arsenic exposure: Evidence from the Strong Heart Study.

    Science.gov (United States)

    Spratlen, Miranda Jones; Gamble, Mary V; Grau-Perez, Maria; Kuo, Chin-Chi; Best, Lyle G; Yracheta, Joseph; Francesconi, Kevin; Goessler, Walter; Mossavar-Rahmani, Yasmin; Hall, Meghan; Umans, Jason G; Fretts, Amanda; Navas-Acien, Ana

    2017-07-01

    B-vitamins involved in one-carbon metabolism (OCM) can affect arsenic metabolism efficiency in highly arsenic exposed, undernourished populations. We evaluated whether dietary intake of OCM nutrients (including vitamins B2, B6, folate (B9), and B12) was associated with arsenic metabolism in a more nourished population exposed to lower arsenic than previously studied. Dietary intake of OCM nutrients and urine arsenic was evaluated in 405 participants from the Strong Heart Study. Arsenic exposure was measured as the sum of iAs, monomethylarsonate (MMA) and dimethylarsenate (DMA) in urine. Arsenic metabolism was measured as the individual percentages of each metabolite over their sum (iAs%, MMA%, DMA%). In adjusted models, increasing intake of vitamins B2 and B6 was associated with modest but significant decreases in iAs% and MMA% and increases in DMA%. A significant interaction was found between high folate and B6 with enhanced arsenic metabolism efficiency. Our findings suggest OCM nutrients may influence arsenic metabolism in populations with moderate arsenic exposure. Stronger and independent associations were observed with B2 and B6, vitamins previously understudied in relation to arsenic. Research is needed to evaluate whether targeting B-vitamin intake can serve as a strategy for the prevention of arsenic-related health effects at low-moderate arsenic exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  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. Arsenic detection in water: YPO4:Eu3+ nanoparticles

    Science.gov (United States)

    Ghosh, Debasish; Luwang, Meitram Niraj

    2015-12-01

    This work reports on the novel technique of detection of arsenic in aqueous solution utilising the luminescence properties of lanthanide doped nanomaterials. Eu3+ (5%) doped YPO4nanorodswere utilised for the said experiment. Co-precipitation method was used for the synthesis of the materials and characterised them with different instrumental techniques like X-ray diffraction (XRD), Infra-red (IR), UV-absorption, scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence studies. This nanoparticle can adsorb both arsenic and arsenious acids. We studied the effect of arsenic adsorption on the luminescence behaviour of the nanoparticles. Arsenic acid enhanced the luminescence intensity whereas arsenious acid quenched the luminescence. This luminescence enhancement or quenching is related with arsenic concentration. This relation of luminescence property with concentration of arsenic can be used to detect arsenic in industrial waste.

  15. Knockdown of TWIST1 enhances arsenic trioxide- and ionizing radiation-induced cell death in lung cancer cells by promoting mitochondrial dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Sung-Keum; Kim, Jae-Hee; Choi, Ha-Na [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul (Korea, Republic of); Choe, Tae-Boo [Department of Microbiological Engineering, Kon-Kuk University, Gwangjin-gu, Seoul (Korea, Republic of); Hong, Seok-Il [Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul (Korea, Republic of); Yi, Jae-Youn [Laboratory of Modulation of Radiobiological Responses, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul (Korea, Republic of); Hwang, Sang-Gu [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul (Korea, Republic of); Lee, Hyun-Gyu [Department of Microbiology and Immunology, College of Medicine, Yonsei University, 250 Seongsan-no, Seodaemun-gu, Seoul (Korea, Republic of); Lee, Yun-Han, E-mail: yhlee87@yuhs.ac [Department of Radiation Oncology, College of Medicine, Yonsei University, 250 Seongsan-no, Seodaemun-gu, Seoul (Korea, Republic of); Park, In-Chul, E-mail: parkic@kcch.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 215-4 Gongneung-dong, Nowon-gu, Seoul (Korea, Republic of)

    2014-07-11

    Highlights: • Knockdown of TWIST1 enhanced ATO- and IR-induced cell death in NSCLCs. • Intracellular ROS levels were increased in cells treated with TWIST1 siRNA. • TWIST1 siRNA induced MMP loss and mitochondrial fragmentation. • TWIST1 siRNA upregulated the fission-related proteins FIS1 and DRP1. - Abstract: TWIST1 is implicated in the process of epithelial mesenchymal transition, metastasis, stemness, and drug resistance in cancer cells, and therefore is a potential target for cancer therapy. In the present study, we found that knockdown of TWIST1 by small interfering RNA (siRNA) enhanced arsenic trioxide (ATO)- and ionizing radiation (IR)-induced cell death in non-small-cell lung cancer cells. Interestingly, intracellular reactive oxygen species levels were increased in cells treated with TWIST1 siRNA and further increased by co-treatment with ATO or IR. Pretreatment of lung cancer cells with the antioxidant N-acetyl-cysteine markedly suppressed the cell death induced by combined treatment with TWIST1 siRNA and ATO or IR. Moreover, treatment of cells with TWIST1 siRNA induced mitochondrial membrane depolarization and significantly increased mitochondrial fragmentation (fission) and upregulated the fission-related proteins FIS1 and DRP1. Collectively, our results demonstrate that siRNA-mediated TWIST1 knockdown induces mitochondrial dysfunction and enhances IR- and ATO-induced cell death in lung cancer cells.

  16. Earth Abides Arsenic Biotransformations

    OpenAIRE

    Zhu, Yong-Guan; Yoshinaga, Masafumi; Zhao, Fang-Jie; Rosen, Barry P.

    2014-01-01

    Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology ...

  17. Enhancement of gold grade through arsenic removal in the gold concentrate using sulfuric acid baking and hot water leaching

    Science.gov (United States)

    On, Hyun-sung; Lim, Dae-hack; Myung, Eun-ji; Kim, Hyun-soo; Park, Cheon-young

    2017-04-01

    In order to improve gold recovery, in general, the roasting process is carried out on gold concentrate. However in this process, Arsenic(As) is released from the gold concentrate and valuable elements such as Fe, Cu, Zn and Pb are converted into oxides. This causes air pollution through the release of As and loss of valuable elements by discarding the oxide minerals in the tailings. In order to prevent the release of As and the loss of valuable metals, an acid baking experiment was carried out on the gold concentrate with the addition of an H2SO4 solution. The baking effect, H2SO4 concentration effect and the effects of changing the baking time were examined using an electric furnace. In experimental results, soluble metal sulfates such as Rhomboclase and Mikasite were formed in the baked samples as seen through XRD analysis. In hot(70 degree Celsius) water leaching of the roast and baked samples, As the contents leached were 60 times more in the baked sample than the roast sample, and the Fe, Cu, Zn and Pb contents were 17, 10, 14, 13 times in the baked sample than in the roast sample, respectively. In the water leached solid-residues, the maximum gold grade was upgraded by 33% due to the acid baking effect. It is confirmed that acid baking with H2SO4 prevented As release into the air and the recovery of valuable metals through hot water leaching such as Fe, Cu, Zn and Pb which were formerly discarded in the tailings. Acknowledgment : This work was supported by the Energy and Resources Engineering Program Grant funded by the Ministry of Trade, Industry and Energy, Korea

  18. Enhanced Photosynthesis and Carbon Metabolism Favor Arsenic Tolerance in Artemisia annua, a Medicinal Plant as Revealed by Homology-Based Proteomics

    Directory of Open Access Journals (Sweden)

    Rashmi Rai

    2014-01-01

    Full Text Available This paper provides the first proteomic evidence of arsenic (As tolerance and interactive regulatory network between primary and secondary metabolism in the medicinal plant, Artemisia annua. While chlorophyll fluorescence and photosynthetic rate depicted mild inhibition, there was a significant enhancement in PSI activity, whole chain, ATP, and NADPH contents in 100 μM As treatments compared to the control plants. However, a decrease in the above variables was recorded under 150 μM treatments. Proteomic decoding of the survival strategy of A. annua under As stress using 2-DE followed by MALDI-MS/MS revealed a total of 46 differentially expressed protein spots. In contrast to other plants where As inhibits photosynthesis, A. annua showed appreciable photosynthetic CO2 assimilation and allocation of carbon resources at 100 μM As concentration. While an increased accumulation of ATP synthase, ferredoxin-NADP(H oxidoreductase, and FeS-rieske proteins supported the operation of cyclic electron transport, mdr ABC transporter protein and pcs gene might be involved in As detoxification. The most interesting observation was an increased accumulation of LEAFY like novel protein conceivably responsible for an early onset of flowering in A. annua under As stress. This study not only affirmed the role of energy metabolism proteins but also identified potential candidates responsible for As tolerance in plants.

  19. Arsenic Treatment Technology Demonstrations

    Science.gov (United States)

    EPA’s research for the new Arsenic Rule focused on the development and evaluation of innovative methods and cost-effective technologies for improving the assessment and control of arsenic contamination.

  20. Fact Sheet on Arsenic

    Science.gov (United States)

    Arsenic is a naturally occurring element that is found in combination with either inorganic or organic substances to form many different compounds. Inorganic arsenic compounds are found in soils, sediments, and groundwater.

  1. 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...

  2. Toxic Substances Portal- Arsenic

    Science.gov (United States)

    ... a naturally occurring element widely distributed in the earth's crust. In the environment, arsenic is combined with ... that inhaled or ingested arsenic can injure pregnant women or their unborn babies, although the studies are ...

  3. Cryptic exposure to arsenic.

    Science.gov (United States)

    Rossy, Kathleen M; Janusz, Christopher A; Schwartz, Robert A

    2005-01-01

    Arsenic is an odorless, colorless and tasteless element long linked with effects on the skin and viscera. Exposure to it may be cryptic. Although human intake can occur from four forms, elemental, inorganic (trivalent and pentavalent arsenic) and organic arsenic, the trivalent inorganic arsenicals constitute the major human hazard. Arsenic usually reaches the skin from occupational, therapeutic, or environmental exposure, although it still may be employed as a poison. Occupations involving new technologies are not exempt from arsenic exposure. Its acute and chronic effects are noteworthy. Treatment options exist for arsenic-induced pathology, but prevention of toxicity remains the main focus. Vitamin and mineral supplementation may play a role in the treatment of arsenic toxicity.

  4. Preparation of arsenic trioxide-loaded microemulsion and its enhanced cytotoxicity on MCF-7 breast carcinoma cell line.

    Science.gov (United States)

    Karasulu, H Yeşim; Karabulut, Bülent; Kantarci, Gülten; Ozgüney, Işik; Sezgin, Canfeza; Sanli, Ulus Ali; Göker, Erdem

    2004-01-01

    In this study, an injectable microemulsion of arsenic trioxide (As2O3-M) was prepared for intratumoral injection and the suppressive effect of As2O3-loaded microemulsion on human breast cancer cells MCF-7 was compared with those of a solution of the drug. Microemulsion was made up of soybean oil as oil phase, a mixture of Brij 58 and Span 80 as surfactants, absolute ethanol as cosurfactant, and bidistilled water containing As2O3 solution as the aqueous phase. Microemulsion formulation contains 5 x 10(-6) M As2O3. The pH of As2O3-M was adjusted to 7.35 +/- 0.1 and the physicochemical stability of the formulation was observed. The particle size distribution and zeta potential of As2O3-M were measured by Zetasizer 3000 HSA. The mean droplet diameters of As2O3-M were determined as 8.6 +/- 0.4 nm. As2O3-M exhibited 13.1 +/- 0.9 mV zeta potential. The formulation was physically stable for 12 months at room temperature when kept in ampule forms, as well as after autoclaving at 110 degrees C for 30 min. The antitumor effects of As2O3-M were examined on human breast cancer cells MCF-7. It was clearly demonstrated that As2O3-M had a significant cytotoxic effect on breast cancer cell lines, and the cytotoxic effect of As2O3-M was significantly more than that of regular As2O3 solutions. Even approximately 3000 times diluted microemulsion formulation loaded with 5 x 10(-6) M As2O3 showed a cytotoxic effect. As a result, this diluted concentration (approximately 1.6 x 10(-9) M) was found 1000 times more effective than regular As2O3 solutions (5 x 10(-6) M). According to the in vitro cytotoxicity studies, we concluded that when As2O3 was incorporated into the microemulsion (As2O3-M), which is a new drug carrier system, it suppresses tumor cell growth on multiple tumor lines. These results indicate that As2O3-M may exert a low cytotoxic effect on normal cells and may be effective as an antitumor agent that induces apoptosis.

  5. Arsenic trioxide overcomes rapamycin-induced feedback activation of AKT and ERK signaling to enhance the anti-tumor effects in breast cancer.

    Science.gov (United States)

    Guilbert, Cynthia; Annis, Matthew G; Dong, Zhifeng; Siegel, Peter M; Miller, Wilson H; Mann, Koren K

    2013-01-01

    Inhibitors of the mammalian target of rapamycin (mTORi) have clinical activity; however, the benefits of mTOR inhibition by rapamycin and rapamycin-derivatives (rapalogs) may be limited by a feedback mechanism that results in AKT activation. Increased AKT activity resulting from mTOR inhibition can be a result of increased signaling via the mTOR complex, TORC2. Previously, we published that arsenic trioxide (ATO) inhibits AKT activity and in some cases, decreases AKT protein expression. Therefore, we propose that combining ATO and rapamycin may circumvent the AKT feedback loop and increase the anti-tumor effects. Using a panel of breast cancer cell lines, we find that ATO, at clinically-achievable doses, can enhance the inhibitory activity of the mTORi temsirolimus. In all cell lines, temsirolimus treatment resulted in AKT activation, which was decreased by concomitant ATO treatment only in those cell lines where ATO enhanced growth inhibition. Treatment with rapalog also results in activated ERK signaling, which is decreased with ATO co-treatment in all cell lines tested. We next tested the toxicity and efficacy of rapamycin plus ATO combination therapy in a MDA-MB-468 breast cancer xenograft model. The drug combination was well-tolerated, and rapamycin did not increase ATO-induced liver enzyme levels. In addition, combination of these drugs was significantly more effective at inhibiting tumor growth compared to individual drug treatments, which corresponded with diminished phospho-Akt and phospho-ERK levels when compared with rapamycin-treated tumors. Therefore, we propose that combining ATO and mTORi may overcome the feedback loop by decreasing activation of the MAPK and AKT signaling pathways.

  6. Arsenic trioxide overcomes rapamycin-induced feedback activation of AKT and ERK signaling to enhance the anti-tumor effects in breast cancer.

    Directory of Open Access Journals (Sweden)

    Cynthia Guilbert

    Full Text Available Inhibitors of the mammalian target of rapamycin (mTORi have clinical activity; however, the benefits of mTOR inhibition by rapamycin and rapamycin-derivatives (rapalogs may be limited by a feedback mechanism that results in AKT activation. Increased AKT activity resulting from mTOR inhibition can be a result of increased signaling via the mTOR complex, TORC2. Previously, we published that arsenic trioxide (ATO inhibits AKT activity and in some cases, decreases AKT protein expression. Therefore, we propose that combining ATO and rapamycin may circumvent the AKT feedback loop and increase the anti-tumor effects. Using a panel of breast cancer cell lines, we find that ATO, at clinically-achievable doses, can enhance the inhibitory activity of the mTORi temsirolimus. In all cell lines, temsirolimus treatment resulted in AKT activation, which was decreased by concomitant ATO treatment only in those cell lines where ATO enhanced growth inhibition. Treatment with rapalog also results in activated ERK signaling, which is decreased with ATO co-treatment in all cell lines tested. We next tested the toxicity and efficacy of rapamycin plus ATO combination therapy in a MDA-MB-468 breast cancer xenograft model. The drug combination was well-tolerated, and rapamycin did not increase ATO-induced liver enzyme levels. In addition, combination of these drugs was significantly more effective at inhibiting tumor growth compared to individual drug treatments, which corresponded with diminished phospho-Akt and phospho-ERK levels when compared with rapamycin-treated tumors. Therefore, we propose that combining ATO and mTORi may overcome the feedback loop by decreasing activation of the MAPK and AKT signaling pathways.

  7. Arsenic Poisoning in Bangladesh

    National Research Council Canada - National Science Library

    Huda , Naz Hasan; Uddin , Riaz

    2011-01-01

    ... in drinking water. (2) People in Bangladesh become terror-stricken when they come to know that underground water in parts of the country is strained by deadly arsenic. The permissible level of arsenic in water is 50 ppb (Parts per billion) according to experts. But according to the Bangladesh Atomic Energy Commission, the level of arsenic is between 150 and 200...

  8. Arsenic: homicidal intoxication

    Energy Technology Data Exchange (ETDEWEB)

    Massey, E.W.; Wold, D.; Heyman, A.

    1984-07-01

    Arsenic-induced deaths have been known to occur from accidental poisoning, as a result of medical therapy, and from intentional poisonings in homicide and suicide. Twenty-eight arsenic deaths in North Carolina from 1972 to 1982 included 14 homicides and seven suicides. In addition, 56 hospitalized victims of arsenic poisoning were identified at Duke Medical Center from 1970 to 1980. Four case histories of arsenic poisoning in North Carolina are presented and clinical manifestations are discussed. In view of the continued widespread use of arsenic in industry and agriculture, and its ubiquity in the environment, arsenic poisoning will continue to occur. A need for knowledge of its toxicity and of the clinical manifestations of acute and chronic arsenic poisoning will also continue.

  9. 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.

  10. Inhibition of mitogen-activated protein kinase kinase enhances apoptosis induced by arsenic trioxide in human breast cancer MCF-7 cells.

    Science.gov (United States)

    Ye, Jian; Li, Aiping; Liu, Qizhan; Wang, Xinru; Zhou, Jianwei

    2005-12-01

    Arsenic trioxide (As2O3) has recently been used to treat acute promyelocytic leukaemia and has activity in vitro against several solid tumour cell lines where the induction of differentiation and apoptosis are the prime effects. The mechanism of As2O3-induced cell death has yet to be clarified, especially in solid cancers. In the present study, the human breast cancer cell line MCF-7 was examined as a cellular model for As2O3 treatment. The involvement of extracellular signal-regulated kinase (ERK), p38 and c-Jun N-terminal kinase (JNK) was investigated in As2O3-induced cell death. 3. It was found that As2O3 activates the prosurvival mitogen-activated protein kinase kinase (MEK)/ERK pathway in MCF-7 cells, which, conversely, may compromise the efficacy of As2O3. Hence, a combination treatment of As2O3 and MEK inhibitors was investigated to determine whether this treatment could lead to enhanced growth inhibition and apoptosis in MCF-7 cells. 4. Inhibition of MEK/ERK with the pharmacological inhibitors U0126 (10 micromol/L) or PD98059 (20 micromol/L) together with As2O3 (2 and 5 micromol/L) resulted in a significant enhancement of growth inhibition in breast cancer MCF-7 cells as determined by the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide assay and [Methyl-3H]-thymidine incorporation. Furthermore, the results demonstrated that combined treatment with As2O3 and the MEK1/2 inhibitor U0126 could augment breast cancer MCF-7 cell apoptosis approximately twofold compared with the effects of the two drugs alone, as determined by Hoechst 33258 or annexin V/propidium iodide (PI) staining and flow cytometry. 5. In addition, As2O3 activated p38 in a dose-dependent manner, but had no effect on JNK1/2. Treatment with a p38 inhibitor did not prevent As2O3-induced apoptosis. 6. In conclusion, the results of the present study showed that enhanced apoptosis is detected in breast cancer MCF-7 cells in the presence of As2O3 and an MEK inhibitor, which may be a

  11. 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 ...

  12. Arsenic biomethylation by photosynthetic organisms

    Science.gov (United States)

    Ye, Jun; Rensing, Christopher; Rosen, Barry P.; Zhu, Yong-Guan

    2013-01-01

    Arsenic (As) is a ubiquitous element that is widespread in the environment and causes numerous health problems. Biomethylation of As has implications for its mobility and toxicity. Photosynthetic organisms may play a significant role in As geochemical cycling by methylating it to different As species, but little is known about the mechanisms of methylation. Methylated As species have been found in many photosynthetic organisms, and several arsenite S-adenosylmethionine (SAM) methyltransferases have been characterized in cyanobacteria and algae. However, higher plants may not have the ability to methylate As. Instead, methylated arsenicals in plants probably originate from microorganisms in soils and the rhizosphere. Here, we propose possible approaches for developing ‘smart’ photosynthetic organisms with an enhanced and sensitive biomethylation capacity for bioremediation and safer food. PMID:22257759

  13. A study on arsenic removal from household drinking water.

    Science.gov (United States)

    Yuan, Tao; Luo, Qi-Fang; Hu, Jiang-Yong; Ong, Say-Leong; Ng, Wun-Jern

    2003-09-01

    Arsenic removal from household drinking water has been receiving considerable attention in the field of water supply engineering. To develop the optimal coagulation protocol, the effectiveness of several operation options such as coagulants, coagulant aids and additives, as well as flocs separation systems were investigated in this study through the use of orthogonal array experiment based on Taguchi method. Arsenic removal mechanism during household coagulation (via manual mixing) was also discussed. The results showed that the addition of kaoline and powder activated carbon (PAC) did not enhance arsenic removal efficiency of ferric sulfate or aluminum sulfate. Similarly, mixture of ferric sulfate and aluminum sulfate (MFA) as well as polymeric ferric silicate sulfate (PFSiS) was also unable to improve the overall arsenic removal efficiency. The mechanism of arsenic removal during coagulation was somewhat different from those experienced in conventional processes. Coprecipitation appeared to be the crucial mechanism for arsenic removal. It is noted from this study that arsenic adsorption isotherm under household operation condition could be described by Langmuir equation. An efficient flocs separation system subsequent to coagulation was essential to achieve the effectiveness of overall arsenic removal. The results obtained from field experiment demonstrated that the method of ferric sulfate coagulation/sand filtration for arsenic removal from household drinking water was acceptable and affordable.

  14. [Acute arsenic poisoning].

    Science.gov (United States)

    Montelescaut, Etienne; Vermeersch, Véronique; Commandeur, Diane; Huynh, Sophie; Danguy des Deserts, Marc; Sapin, Jeanne; Ould-Ahmed, Mehdi; Drouillard, Isabelle

    2014-01-01

    Acute arsenic poisoning is a rare cause of suicide attempt. It causes a multiple organs failure caused by cardiogenic shock. We report the case of a patient admitted twelve hours after an ingestion of trioxide arsenic having survived thanks to a premature treatment.

  15. 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.

  16. Chronic Arsenic poisoning.

    Science.gov (United States)

    Ahsan, Tasnim; Zehra, Kaneez; Munshi, Alia; Ahsan, Samiah

    2009-02-01

    Chronic Arsenic Toxicity may have varied clinical presentations ranging from non-cancerous manifestations to malignancy of skin and different internal organs. Dermal lesions such as hyper pigmentation and hyperkeratosis, predominantly over palms and soles are diagnostic of Chronic Arsenicosis. We report two cases from a family living in Sukkur who presented with classical skin lesions described in Chronic Arsenicosis. The urine, nail and hair samples of these patients contained markedly elevated levels of arsenic. Also the water samples from their household and the neighbouring households were found to have alarming levels of inorganic Arsenic.

  17. 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

  18. Arsenic speciation results

    Data.gov (United States)

    U.S. Environmental Protection Agency — Linear combination fitting results of synchrotron data to determine arsenic speciation in soil samples. This dataset is associated with the following publication:...

  19. Arsenic Trioxide Injection

    Science.gov (United States)

    ... have not been helped by other types of chemotherapy or whose condition has improved but then worsened following treatment with other types of chemotherapy. Arsenic trioxide is in a class of medications ...

  20. Chromated Arsenicals (CCA)

    Science.gov (United States)

    Chromated copper arsenate (CCA) is a wood preservative pesticide containing chromium, copper, and arsenic that protects wood against termites, fungi, mites and other pests that can degrade or threaten the integrity of wood products.

  1. Arsenic immunotoxicity: a review

    National Research Council Canada - National Science Library

    Dangleben, Nygerma L; Skibola, Christine F; Smith, Martyn T

    2013-01-01

    Exposure to arsenic (As) is a global public health problem because of its association with various cancers and numerous other pathological effects, and millions of people worldwide are exposed to As on a regular basis...

  2. Mobilization of arsenic from contaminated sediment by anionic and nonionic surfactants.

    Science.gov (United States)

    Liang, Chuan; Peng, Xianjia

    2017-06-01

    The increasing manufacture of surfactants and their wide application in industry, agriculture and household detergents have resulted in large amounts of surfactant residuals being discharged into water and distributed into sediment. Surfactants have the potential to enhance arsenic mobility, leading to risks to the environment and even human beings. In this study, batch and column experiments were conducted to investigate arsenic mobilization from contaminated sediment by the commercial anionic surfactants sodium dodecylbenzenesulfonate (SDBS), sodium dodecyl sulfate (SDS), sodium laureth sulfate (AES) and nonionic surfactants phenyl-polyethylene glycol (Triton X-100) and polyethylene glycol sorbitan monooleate (Tween-80). The ability of surfactants to mobilize arsenic followed the order AES>SDBS>SDS≈Triton X-100>Tween 80. Arsenic mobilization by AES and Triton X-100 increased greatly with the increase of surfactant concentration and pH, while arsenic release by SDBS, SDS and Tween-80 slightly increased. The divalent ion Ca2+ caused greater reduction of arsenic mobilization than Na+. Sequential extraction experiments showed that the main fraction of arsenic mobilized was the specifically adsorbed fraction. Solid phase extraction showed that arsenate (As(V)) was the main species mobilized by surfactants, accounting for 65.05%-77.68% of the total mobilized arsenic. The mobilization of arsenic was positively correlated with the mobilization of iron species. The main fraction of mobilized arsenic was the dissolved fraction, accounting for 70% of total mobilized arsenic. Copyright © 2016. Published by Elsevier B.V.

  3. 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.

  4. Arsenic and diabetes: Current perspectives

    OpenAIRE

    Chun Fa Huang; Ya Wen Chen; Ching Yao Yang; Keh Sung Tsai; Rong Sen Yang; Shing Hwa Liu

    2011-01-01

    Arsenic is a naturally occurring toxic metalloid of global concern. Many studies have indicated a dose–response relationship between accumulative arsenic exposure and the prevalence of diabetes mellitus (DM) in arseniasis-endemic areas in Taiwan and Bangladesh, where arsenic exposure occurs through drinking water. Epidemiological researches have suggested that the characteristics of arsenic-induced DM observed in arseniasis-endemic areas in Taiwan and Mexico are similar to those of non-insuli...

  5. Arsenic: The Silent Killer

    Energy Technology Data Exchange (ETDEWEB)

    Foster, Andrea (USGS)

    2006-02-28

    Andrea Foster uses x-rays to determine the forms of potentially toxic elements in environmentally-important matrices such as water, sediments, plants, and microorganisms. In this free public lecture, Foster will discuss her research on arsenic, which is called the silent killer because dissolved in water, it is colorless, odorless, and tasteless, yet consumption of relatively small doses of this element in its most toxic forms can cause rapid and violent death. Arsenic is a well-known poison, and has been used as such since ancient times. Less well known is the fact that much lower doses of the element, consumed over years, can lead to a variety of skin and internal cancers that can also be fatal. Currently, what has been called the largest mass poisoning in history is occurring in Bangladesh, where most people are by necessity drinking ground water that is contaminated with arsenic far in excess of the maximum amounts determined to be safe by the World Health Organization. This presentation will review the long and complicated history with arsenic, describe how x-rays have helped explain the high yet spatially variable arsenic concentrations in Bangladesh, discuss the ways in which land use in Bangladesh may be exacerbating the problem, and summarize the impact of this silent killer on drinking water systems worldwide.

  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.

    Science.gov (United States)

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

    2009-09-01

    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 microg/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 microg/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 predominantly at low-to-moderate levels (0.1 to 864 microg/L, mean 99 microg/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. 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

    Science.gov (United States)

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

    2012-01-01

    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. PMID:19371619

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Arsenic and Selenium

    Science.gov (United States)

    Plant, J. A.; Kinniburgh, D. G.; Smedley, P. L.; Fordyce, F. M.; Klinck, B. A.

    2003-12-01

    Arsenic (As) and selenium (Se) have become increasingly important in environmental geochemistry because of their significance to human health. Their concentrations vary markedly in the environment, partly in relation to geology and partly as a result of human activity. Some of the contamination evident today probably dates back to the first settled civilizations which used metals.Arsenic is in group 15 of the periodic table (Table 1) and is usually described as a metalloid. It has only one stable isotope, 75As. It can exist in the -III, -I, 0, III, and V oxidation states (Table 2).

  14. 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 ...

  15. The role of arsenic compounds in oxidative stress and in the development of diabetes

    Directory of Open Access Journals (Sweden)

    Anna Bizoń

    2013-09-01

    Full Text Available For many years arsenic compounds were used in medicine, including treatment of skin diseases, malaria, diabetes, malaria, stomach ulcers, leukemia and in the eighteenth and the nineteenth century formed the basis of contemporary pharmacology. Due to its toxicity and carcinogenic activity, most of the compounds of this element were removed from use. The major cause of human arsenic toxicity is attributed to contamination of potable water from natural geological sources rather than from mining, smelting and agricultural sources (pesticides or fertilizers. Tobacco smoke also contains arsenic compounds. The characteristics of severe acute arsenic toxicity in humans include gastrointestinal discomfort, vomiting, diarrhea, skin lesions or even death. Chronic exposure frequently causes vascoocclusive disease (such as Blackfoot disease, and the development of lung, skin, liver, kidney and bladder cancers. Arsenic is a pro-inflammatory metal and appears to induce oxidative stress, apoptosis, affect cell proliferation and cell cycle progression. Generation of free radicals by arsenic is associated with its genotoxicity and contributes to the development of neoplastic lesions. Exposure to arsenic can also cause damage of the central nervous system, peripheral neuropathies, and behavioral changes. It was shown the association of exposure to arsenic and type 2 diabetes. Compounds with +3 oxidation state are more toxic and can induce tumor development. Arsenic interacts with other heavy metals, e.g. enhances the toxicity of cadmium nephropathy and acts antagonistically relative to selenium. Studies on the mechanism of interacting the toxicity of arsenic in the human body are crucial and point to lack of access to pure potable water in some regions of the world. People should be aware of the risks that are associated with exposure to arsenic because it is ubiquitous in the industry, as well as the environment. Arsenic is also involved in the spread of

  16. Arsenic accumulation in rice (Oryza sativa L.): human exposure through food chain.

    Science.gov (United States)

    Azizur Rahman, M; Hasegawa, H; Mahfuzur Rahman, M; Mazid Miah, M A; Tasmin, A

    2008-02-01

    Although human exposure to arsenic is thought to be caused mainly through arsenic-contaminated underground drinking water, the use of this water for irrigation enhances the possibility of arsenic uptake into crop plants. Rice is the staple food grain in Bangladesh. Arsenic content in straw, grain and husk of rice is especially important since paddy fields are extensively irrigated with underground water having high level of arsenic concentration. However, straw and husk are widely used as cattle feed. Arsenic concentration in rice grain was 0.5+/-0.02 mg kg(-1) with the highest concentrations being in grains grown on soil treated with 40 mg As kg(-1) soil. With the average rice consumption between 400 and 650 g/day by typical adults in the arsenic-affected areas of Bangladesh, the intake of arsenic through rice stood at 0.20-0.35 mg/day. With a daily consumption of 4 L drinking water, arsenic intake through drinking water stands at 0.2mg/day. Moreover, when the rice plant was grown in 60 mg of As kg(-1) soil, arsenic concentrations in rice straw were 20.6+/-0.52 at panicle initiation stage and 23.7+/-0.44 at maturity stage, whereas it was 1.6+/-0.20 mg kg(-1) in husk. Cattle drink a considerable amount of water. So alike human beings, arsenic gets deposited into cattle body through rice straw and husk as well as from drinking water which in turn finds a route into the human body. Arsenic intake in human body from rice and cattle could be potentially important and it exists in addition to that from drinking water. Therefore, a hypothesis has been put forward elucidating the possible food chain pathways through which arsenic may enter into human body.

  17. Bioremediation of Arsenic: Prospects and Limitations in the Agriculture of Bangladesh

    Directory of Open Access Journals (Sweden)

    MOHAMMAD ZABED HOSSAIN

    2012-06-01

    Full Text Available Arsenic contamination in the groundwater of Bangladesh has been termed as one of the largest mass poisoning in history. The problem of arsenic toxicity in crop plants that occurs through transfer of arsenic from contaminated soil to plant parts is of great concern because of its potential health hazards. Among the various method, bioremediation of arsenic is the most desirable because of low coast, environmental safety and sustainability. This article focuses on the potential of using various methods for arsenic bioremediation and discusses the advantages and challenges of these methods with special emphasis on the problem of Bangladesh. Although remediation through phytoextraction of arsenic in soil seems promissing, disposing plants used as hyper-accumulator is a concern for the environment. Moreover, further improvement of phytoextraction is needed due to the severity of arsenic contamination in the agricultural soils of Bangladesh. Using soil microbes for bioremediatioin also needs further research in order to enhance our knowledge abut the efficient methods suitable for Bangladesh. Information gathered in this article is likely to enhance our knowledge about the arsenic bioremediation among the stakeholders including the policy makers in countries like Bangladesh where the problem of arsenic contamination in agricultural soil is severe.

  18. Efficacy of arsenic filtration by Kanchan arsenic filter in Nepal.

    Science.gov (United States)

    Singh, Anjana; Smith, Linda S; Shrestha, Shreekrishna; Maden, Narendra

    2014-09-01

    Groundwater arsenic contamination has caused a significant public health burden in lowland regions of Nepal. For arsenic mitigation purposes, the Kanchan Arsenic Filter (KAF) was developed and validated for use in 2003 after pilot studies showed its effectiveness in removing arsenic. However, its efficacy in field conditions operating for a long period has been scarcely observed. In this study, we observe the efficacy of KAFs running over 6 months in highly arsenic-affected households in Nawalparasi district. We assessed pair-wise arsenic concentrations of 62 randomly selected household tubewells before filtration and after filtration via KAFs. Of 62 tubewells, 41 had influent arsenic concentration exceeding the Nepal drinking water quality standard value (50 μg/L). Of the 41 tubewells having unsafe arsenic levels, KAFs reduced arsenic concentration to the safe level for only 22 tubewells, an efficacy of 54%. In conclusion, we did not find significantly high efficacy of KAFs in reducing unsafe influent arsenic level to the safe level under the in situ field conditions.

  19. Indomethacin-Enhanced Anticancer Effect of Arsenic Trioxide in A549 Cell Line: Involvement of Apoptosis and Phospho-ERK and p38 MAPK Pathways

    Directory of Open Access Journals (Sweden)

    Ali Mandegary

    2013-01-01

    Full Text Available Background. Focusing on novel drug combinations that target different pathways especially apoptosis and MAPK could be a rationale for combination therapy in successful treatment of lung cancer. Concurrent use of cyclooxygenase (COX inhibitors with arsenic trioxide (ATO might be a possible treatment option. Methods. Cytotoxicity of ATO, dexamethasone (Dex, celecoxib (Cel, and Indomethacin (Indo individually or in combination was determined at 24, 48, and 72 hrs in A549 lung cancer cells. The COX-2 gene and protein expression, MAPK pathway proteins, and caspase-3 activity were studied for the most cytotoxic combinations. Results. The IC50s of ATO and Indo were 68.7 μmol/L and 396.5 μmol/L, respectively. Treatment of cells with combinations of clinically relevant concentrations of ATO and Indo resulted in greater growth inhibition and apoptosis induction than did either agent alone. Caspase-3 activity was considerably high in the presence of ATO and Indo but showed no difference in single or combination use. Phosphorylation of p38 and ERK1/2 was remarkable in the concurrent presence of both drugs. Conclusions. Combination therapy with ATO and Indo exerted a very potent in vitro cytotoxic effect against A549 lung cancer cells. Activation of ERK and p38 pathways might be the mechanism of higher cytotoxic effect of ATO-Indo combination.

  20. Induction of NKG2D ligands and subsequent enhancement of NK cell-mediated lysis of cancer cells by arsenic trioxide.

    Science.gov (United States)

    Kim, Joo-Young; Bae, Jae-Ho; Lee, Sang-Hwa; Lee, Eun-Yup; Chung, Byung-Seon; Kim, Sun-Hee; Kang, Chi-Dug

    2008-06-01

    Natural killer (NK) cells are important effector cells in immune responses to tumor cells and the activation of NK cells is mediated through specific interactions between activating receptors and their cognate ligands. Recently, it has been demonstrated that induction of NKG2D ligands on tumor cells by various stresses render them more sensitive to NK cell-mediated killing. Therefore, in this study, it was investigated whether arsenic trioxide (ATO) could up-regulate NKG2D ligands on tumor cells and increase the susceptibility of cancer cells against NK cells. ATO increased transcription of NKG2D ligands, predominantly ULBP1, in various cancer cell lines, such as K562 chronic myelogenous leukemic cells, NB4 acute promyelocytic leukemic cells, and MCF7 breast cancer cells, and subsequently the surface expression of NKG2D ligands. These results were followed by increased susceptibility of cancer cells to NK cell-mediated cytotoxicity after treatment with ATO. This increase in cytotoxicity was abolished by addition of a blocking NKG2D monoclonal antibody, indicating that the increased susceptibility of ATO-treated cancer cells to cytotoxicity of NK cells was mediated through up-regulation of NKG2D ligands. In addition, abrogation of heat shock proteins induction with KNK437 would sensitize the ATO-treated MCF-7 cells to NK cell-mediated killing. This study suggests that the immunomodulatory property of ATO would be an attractive strategy to improve the effectiveness of NK cell-based cancer immunotherapy.

  1. Arsenic and diabetes: current perspectives.

    Science.gov (United States)

    Huang, Chun Fa; Chen, Ya Wen; Yang, Ching Yao; Tsai, Keh Sung; Yang, Rong Sen; Liu, Shing Hwa

    2011-09-01

    Arsenic is a naturally occurring toxic metalloid of global concern. Many studies have indicated a dose-response relationship between accumulative arsenic exposure and the prevalence of diabetes mellitus (DM) in arseniasis-endemic areas in Taiwan and Bangladesh, where arsenic exposure occurs through drinking water. Epidemiological researches have suggested that the characteristics of arsenic-induced DM observed in arseniasis-endemic areas in Taiwan and Mexico are similar to those of non-insulin-dependent DM (Type 2 DM). These studies analyzed the association between high and chronic exposure to inorganic arsenic in drinking water and the development of DM, but the effect of exposure to low to moderate levels of inorganic arsenic on the risk of DM is unclear. Navas-Acien et al. recently proposed that a positive association existed between total urine arsenic and the prevalence of Type 2 DM in people exposed to low to moderate levels of arsenic. However, the diabetogenic role played by arsenic is still debated upon. An increase in the prevalence of DM has been observed among residents of highly arsenic-contaminated areas, whereas the findings from community-based and occupational studies in low-arsenic-exposure areas have been inconsistent. Recently, a population-based cross-sectional study showed that the current findings did not support an association between arsenic exposure from drinking water at levels less than 300 μg/L and a significantly increased risk of DM. Moreover, although the precise mechanisms for the arsenic-induced diabetogenic effect are still largely undefined, recent in vitro experimental studies indicated that inorganic arsenic or its metabolites impair insulin-dependent glucose uptake or glucose-stimulated insulin secretion. Nevertheless, the dose, the form of arsenic used, and the experimental duration in the in vivo studies varied greatly, leading to conflicting results and ambiguous interpretation of these data with respect to human exposure

  2. Arsenic and diabetes: Current perspectives

    Directory of Open Access Journals (Sweden)

    Chun Fa Huang

    2011-09-01

    Full Text Available Arsenic is a naturally occurring toxic metalloid of global concern. Many studies have indicated a dose–response relationship between accumulative arsenic exposure and the prevalence of diabetes mellitus (DM in arseniasis-endemic areas in Taiwan and Bangladesh, where arsenic exposure occurs through drinking water. Epidemiological researches have suggested that the characteristics of arsenic-induced DM observed in arseniasis-endemic areas in Taiwan and Mexico are similar to those of non-insulin-dependent DM (Type 2 DM. These studies analyzed the association between high and chronic exposure to inorganic arsenic in drinking water and the development of DM, but the effect of exposure to low to moderate levels of inorganic arsenic on the risk of DM is unclear. Navas-Acien et al. recently proposed that a positive association existed between total urine arsenic and the prevalence of Type 2 DM in people exposed to low to moderate levels of arsenic. However, the diabetogenic role played by arsenic is still debated upon. An increase in the prevalence of DM has been observed among residents of highly arsenic-contaminated areas, whereas the findings from community-based and occupational studies in low-arsenic-exposure areas have been inconsistent. Recently, a population-based cross-sectional study showed that the current findings did not support an association between arsenic exposure from drinking water at levels less than 300 μg/L and a significantly increased risk of DM. Moreover, although the precise mechanisms for the arsenic-induced diabetogenic effect are still largely undefined, recent in vitro experimental studies indicated that inorganic arsenic or its metabolites impair insulin-dependent glucose uptake or glucose-stimulated insulin secretion. Nevertheless, the dose, the form of arsenic used, and the experimental duration in the in vivo studies varied greatly, leading to conflicting results and ambiguous interpretation of these data with

  3. Questions and Answers: Apple Juice and Arsenic

    Science.gov (United States)

    ... for You Consumers Questions & Answers: Apple Juice and Arsenic Share Tweet Linkedin Pin it More sharing options ... it Email Print July 15, 2013 What is arsenic? Arsenic is present in the environment as a ...

  4. Removal of arsenic using reverse osmosis

    OpenAIRE

    Fauskrud, Marie

    2013-01-01

    Master's thesis in Water and Enviromental Technology Arsenic is an element that naturally occurs in rocks and sediments. In some areas, arsenic is released to ground water and can contaminate drinking water sources. Since arsenic is toxic in high doses and a carcinogen, the World Health Organisation (WHO) recommends arsenic levels lower than 10 μg/L in drinking water. This thesis describes the removal of arsenic in a reverse osmosis system. Arsenic is usually present in water in two oxi...

  5. Rural methods to mitigate arsenic contaminated water

    OpenAIRE

    Parajuli, Krishna

    2013-01-01

    Consumption of arsenic contaminated water is one of the burning issues in the rural world. Poor public awareness program about health effects of drinking arsenic contaminated water and the rural methods to mitigate this problem poses a great threat of arsenic poisoning many people of the rural world. In this thesis, arsenic removal efficiency and the working mechanism of four rural and economical arsenic mitigation technologies i.e. solar oxidation and reduction of arsenic (SORAS), Bucket tr...

  6. Arsenic hexoxide enhances TNF-α-induced anticancer effects by inhibiting NF-κB activity at a safe dose in MCF-7 human breast cancer cells.

    Science.gov (United States)

    Kim, Min Jeong; Jung, Ji Hyun; Lee, Won Sup; Yun, Jeong Won; Lu, Jing Nan; Yi, Sang Mi; Kim, Hye Jung; Chang, Seong-Hwan; Kim, Gon-Sup; Hong, Soon Chan; Ha, Woo Song

    2014-05-01

    Arsenic hexoxide (As4O6) has been used in Korean folk remedy for the treatment of cancer since the late 1980s. Evidence suggests that the anticancer effects of As4O6 are different from those of As2O3. Tumor necrosis factor-α (TNF-α) is generally increased in advanced cancer and is closely related to cancer progression, although it has cancer-killing effects. The reason is that TNF-α activates nuclear factor-κB (NF-κB) that is involved in cell proliferation, invasion, drug resistance and metastasis. In the present study, we investigated the effects of As4O6 on NF-κB activity, NF-κB-mediated cellular responses, and NF-κB-regulated gene expressions involved in metastasis at the concentrations of As4O6 where no cytotoxicity was observed. As4O6 suppressed NF-κB activation in both TNF-α-treated and control cells, and also suppressed IκB phosphorylation in a time-dependent manner, suggesting the suppression of NF-κB results, in part, from the inhibition of IκB degradation. We also confirmed the anti-NF-κB activity of As4O6 with synergism with TNF-α by augmenting caspase-8 activation. As4O6 also suppressed NF-κB activation induced by TNF-α, and some of the downstream NF-κB-regulated proteins involved in cancer proliferation, anti-apoptosis and metastasis. In conclusion, the present study demonstrated that As4O6 has anticancer properties by inhibiting NF-κB activation and NF-κB-regulated proteins at least in part through the inhibition of IκB phosphorylation, especially in the conditions of advanced cancer where TNF-α is highly secreted.

  7. 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.

  8. Role of Aspergillus niger acrA in Arsenic Resistance and Its Use as the Basis for an Arsenic Biosensor

    Science.gov (United States)

    Choe, Se-In; Gravelat, Fabrice N.; Al Abdallah, Qusai; Lee, Mark J.; Gibbs, Bernard F.

    2012-01-01

    Arsenic contamination of groundwater sources is a major issue worldwide, since exposure to high levels of arsenic has been linked to a variety of health problems. Effective methods of detection are thus greatly needed as preventive measures. In an effort to develop a fungal biosensor for arsenic, we first identified seven putative arsenic metabolism and transport genes in Aspergillus niger, a widely used industrial organism that is generally regarded as safe (GRAS). Among the genes tested for RNA expression in response to arsenate, acrA, encoding a putative plasma membrane arsenite efflux pump, displayed an over 200-fold increase in gene expression in response to arsenate. We characterized the function of this A. niger protein in arsenic efflux by gene knockout and confirmed that AcrA was located at the cell membrane using an enhanced green fluorescent protein (eGFP) fusion construct. Based on our observations, we developed a putative biosensor strain containing a construct of the native promoter of acrA fused with egfp. We analyzed the fluorescence of this biosensor strain in the presence of arsenic using confocal microscopy and spectrofluorimetry. The biosensor strain reliably detected both arsenite and arsenate in the range of 1.8 to 180 μg/liter, which encompasses the threshold concentrations for drinking water set by the World Health Organization (10 and 50 μg/liter). PMID:22467499

  9. Effects of in utero arsenic exposure on child immunity and morbidity in rural Bangladesh.

    Science.gov (United States)

    Raqib, Rubhana; Ahmed, Sultan; Sultana, Rokeya; Wagatsuma, Yukiko; Mondal, Dinesh; Hoque, A M Waheedul; Nermell, Barbro; Yunus, Mohammed; Roy, Shantonu; Persson, Lars Ake; Arifeen, Shams El; Moore, Sophie; Vahter, Marie

    2009-03-28

    Chronic exposure to arsenic, a potent carcinogen and toxicant, via drinking water is a worldwide public health problem. Because little is known about early-life effects of arsenic on immunity, we evaluated the impact of in utero exposure on infant immune parameters and morbidity in a pilot study. Pregnant women were enrolled at 6-10 weeks of gestation in Matlab, a rural area of Bangladesh, extensively affected by arsenic contamination of tubewell water. Women (n=140) delivering at local clinics were included in the study. Anthropometry and morbidity data of the pregnant women and their children, as well as infant thymic size by sonography were collected. Maternal urine and breast milk were collected for immune marker and arsenic assessment. Maternal urinary arsenic during pregnancy showed significant negative correlation with interleukin-7 (IL-7) and lactoferrin (Ltf) in breast milk and child thymic index (TI). Urinary arsenic was also positively associated with fever and diarrhea during pregnancy and acute respiratory infections (ARI) in the infants. The effect of arsenic exposure on ARI was only evident in male children. The findings suggest that in utero arsenic exposure impaired child thymic development and enhanced morbidity, probably via immunosuppression. The effect seemed to be partially gender dependent. Arsenic exposure also affected breast milk content of trophic factors and maternal morbidity.

  10. Arsenic poisoning of Bangladesh groundwater

    Science.gov (United States)

    Nickson, Ross; McArthur, John; Burgess, William; Ahmed, Kazi Matin; Ravenscroft, Peter; Rahmanñ, Mizanur

    1998-09-01

    In Bangladesh and West Bengal, alluvial Ganges aquifers used for public water supply are polluted with naturally occurring arsenic, which adversely affects the health of millions of people. Here we show that the arsenic derives from the reductive dissolution of arsenic-rich iron oxyhydroxides, which in turn are derived from weathering of base-metal sulphides. This finding means it should now be possible, by sedimentological study of the Ganges alluvial sediments, to guide the placement of new water wells so they will be free of arsenic.

  11. Identification of An Arsenic Tolerant Double Mutant With a Thiol-Mediated Component And Increased Arsenic Tolerance in PhyA Mutants

    Energy Technology Data Exchange (ETDEWEB)

    Sung, D.Y.; Lee, D.; Harris, H.; Raab, A.; Feldmann, J.; Meharg, A.; Kumabe, B.; Komives, E.A.; Schroeder, J.I.; /SLAC, SSRL /Sydney U. /Aberdeen U. /UC, San Diego

    2007-04-06

    A genetic screen was performed to isolate mutants showing increased arsenic tolerance using an Arabidopsis thaliana population of activation tagged lines. The most arsenic-resistant mutant shows increased arsenate and arsenite tolerance. Genetic analyses of the mutant indicate that the mutant contains two loci that contribute to arsenic tolerance, designated ars4 and ars5. The ars4ars5 double mutant contains a single T-DNA insertion, ars4, which co-segregates with arsenic tolerance and is inserted in the Phytochrome A (PHYA) gene, strongly reducing the expression of PHYA. When grown under far-red light conditions ars4ars5 shows the same elongated hypocotyl phenotype as the previously described strong phyA-211 allele. Three independent phyA alleles, ars4, phyA-211 and a new T-DNA insertion allele (phyA-t) show increased tolerance to arsenate, although to a lesser degree than the ars4ars5 double mutant. Analyses of the ars5 single mutant show that ars5 exhibits stronger arsenic tolerance than ars4, and that ars5 is not linked to ars4. Arsenic tolerance assays with phyB-9 and phot1/phot2 mutants show that these photoreceptor mutants do not exhibit phyA-like arsenic tolerance. Fluorescence HPLC analyses show that elevated levels of phytochelatins were not detected in ars4, ars5 or ars4ars5, however increases in the thiols cysteine, gamma-glutamylcysteine and glutathione were observed. Compared with wild type, the total thiol levels in ars4, ars5 and ars4ars5 mutants were increased up to 80% with combined buthionine sulfoximine and arsenic treatments, suggesting the enhancement of mechanisms that mediate thiol synthesis in the mutants. The presented findings show that PHYA negatively regulates a pathway conferring arsenic tolerance, and that an enhanced thiol synthesis mechanism contributes to the arsenic tolerance of ars4ars5.

  12. INFLUENCE OF DIETARY ARSENIC ON URINARY ARSENIC METABOLITE EXCRETION

    Science.gov (United States)

    Influence of Dietary Arsenic on Urinary Arsenic Metabolite ExcretionCara L. Carty, M.S., Edward E. Hudgens, B.Sc., Rebecca L. Calderon, Ph.D., M.S.P.H., Richard Kwok, M.S.P.H., Epidemiology and Biomarkers Branch/HSD, NHEERL/US EPA; David J. Thomas, Ph.D., Pharmacokinetics...

  13. 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.

  14. Arsenic speciation in edible mushrooms.

    Science.gov (United States)

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

    2014-12-16

    The fruiting bodies, or mushrooms, of terrestrial fungi have been found to contain a high proportion of the nontoxic arsenic compound arsenobetaine (AB), but data gaps include a limited phylogenetic diversity of the fungi for which arsenic speciation is available, a focus on mushrooms with higher total arsenic concentrations, and the unknown formation and role of AB in mushrooms. To address these, the mushrooms of 46 different fungus species (73 samples) over a diverse range of phylogenetic groups were collected from Canadian grocery stores and background and arsenic-contaminated areas. Total arsenic was determined using ICP-MS, and arsenic speciation was determined using HPLC-ICP-MS and complementary X-ray absorption spectroscopy (XAS). The major arsenic compounds in mushrooms were found to be similar among phylogenetic groups, and AB was found to be the major compound in the Lycoperdaceae and Agaricaceae families but generally absent in log-growing mushrooms, suggesting the microbial community may influence arsenic speciation in mushrooms. The high proportion of AB in mushrooms with puffball or gilled morphologies may suggest that AB acts as an osmolyte in certain mushrooms to help maintain fruiting body structure. The presence of an As(III)-sulfur compound, for the first time in mushrooms, was identified in the XAS analysis. Except for Agaricus sp. (with predominantly AB), inorganic arsenic predominated in most of the store-bought mushrooms (albeit with low total arsenic concentrations). Should inorganic arsenic predominate in these mushrooms from contaminated areas, the risk to consumers under these circumstances should be considered.

  15. Arsenic levels in groundwater aquifer

    African Journals Online (AJOL)

    Miodrag Jelic

    Varying levels of arsenic in both industrial and sanitary waters were determined, indicating water pollution with arsenic compounds. The horizontal ...... Geochem. 113: 163-181. Thu LT, Quang Toan ET (2001). Country Report of Vietnam. Workshop on Drinking Water Quality Surveillance and Safety, Kuala Lumpur: pp. 42-48 ...

  16. Drinking Water Arsenic Rule History

    Science.gov (United States)

    The EPA published the final arsenic rule on January 22, 2001. In response to the national debate surrounding the arsenic rule related to science and costs, the EPA announced on March 20, 2001 that the agency would reassess the science and cost issues.

  17. Bioscorodite crystallization for arsenic removal

    NARCIS (Netherlands)

    Gonzalez-Contreras, P.A.; Huisman, J.; Weijma, J.; Buisman, C.J.N.

    2011-01-01

    In the bio-scorodite process, arsenic is precipitated as crystalline iron arsenate, i.e. scorodite (FeAsO4·2H2O). This is a more economic and more environmentally friendly method for arsenic immobilization than the chemical production of iron- or calcium arsenate, as fewer chemicals are needed.

  18. ARSENIC - SUSCEPTIBILITY & IN UTERO EFFECTS

    Science.gov (United States)

    Exposure to inorganic arsenic remains a serious public health problem at many locations worldwide. If has often been noted that prevalences of signs and symptoms of chronic arsenic poisoning differ among various populations. For example, skin lesions or peripheral vascular dis...

  19. Arsenic Mobility and Groundwater Extraction in Bangladesh

    Science.gov (United States)

    Harvey, Charles F.; Swartz, Christopher H.; Badruzzaman, A. B. M.; Keon-Blute, Nicole; Yu, Winston; Ali, M. Ashraf; Jay, Jenny; Beckie, Roger; Niedan, Volker; Brabander, Daniel; Oates, Peter M.; Ashfaque, Khandaker N.; Islam, Shafiqul; Hemond, Harold F.; Ahmed, M. Feroze

    2002-11-01

    High levels of arsenic in well water are causing widespread poisoning in Bangladesh. In a typical aquifer in southern Bangladesh, chemical data imply that arsenic mobilization is associated with recent inflow of carbon. High concentrations of radiocarbon-young methane indicate that young carbon has driven recent biogeochemical processes, and irrigation pumping is sufficient to have drawn water to the depth where dissolved arsenic is at a maximum. The results of field injection of molasses, nitrate, and low-arsenic water show that organic carbon or its degradation products may quickly mobilize arsenic, oxidants may lower arsenic concentrations, and sorption of arsenic is limited by saturation of aquifer materials.

  20. 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...

  1. Organic matter-solid phase interactions are critical for predicting arsenic release and plant uptake in Bangladesh paddy soils.

    Science.gov (United States)

    Williams, Paul N; Zhang, Hao; Davison, William; Meharg, Andrew A; Hossain, Mahmud; Norton, Gareth J; Brammer, Hugh; Islam, M Rafiqul

    2011-07-15

    Agroecological zones within Bangladesh with low levels of arsenic in groundwater and soils produce rice that is high in arsenic with respect to other producing regions of the globe. Little is known about arsenic cycling in these soils and the labile fractions relevant for plant uptake when flooded. Soil porewater dynamics of field soils (n = 39) were recreated under standardized laboratory conditions to investigate the mobility and interplay of arsenic, Fe, Si, C, and other elements, in relation to rice grain element composition, using the dynamic sampling technique diffusive gradients in thin films (DGT). Based on a simple model using only labile DGT measured arsenic and dissolved organic carbon (DOC), concentrations of arsenic in Aman (Monsoon season) rice grain were predicted reliably. DOC was the strongest determinant of arsenic solid-solution phase partitioning, while arsenic release to the soil porewater was shown to be decoupled from that of Fe. This study demonstrates the dual importance of organic matter (OM), in terms of enhancing arsenic release from soils, while reducing bioavailability by sequestering arsenic in solution.

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

    Science.gov (United States)

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

    2006-01-01

    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 was observed in Matrigel plugs implanted in C57BL/6 mice following 5 week exposures to 5-500 ppb arsenic (Soucy et al., 2005). 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. PMID:17123562

  3. Improved Aeration Process - Catalytic Role Of The Iron Oxides In Arsenic Oxidation And Coprecipitation

    DEFF Research Database (Denmark)

    Kowalski, Krysztof; Søgaard, Erik Gydesen

    2013-01-01

    Demands for a better drinking water quality, especially concerning arsenic, a compound with many adverse health effects, put a pressure on the utilities to ensure the best treatment technologies that meet nowadays and possible future quality standards. The aim of this paper is to introduce...... an improved aeration process that can also help in developing better arsenic removal treatment. The results present advantages of arsenic oxidation in an aeration process in the presence of ferrihydrite surface that have been shown to adsorb arsenic simultaneously to its oxidation. The presence...... of precipitated (ferrihydrite surface) and dissolved iron enhanced arsenic oxidation in comparison to solution with absence of precipitated iron in laboratory scale experiments. However, in the pilot scale studies the adsorption of arsenite on ferrihydrite was found to be the main process occurring during...

  4. Osteoresorptive arsenic intoxication.

    Science.gov (United States)

    Dani, Sergio Ulhoa

    2013-04-01

    A 47-year-old woman consulted her dermatologist complaining whole body dermatitis, urticaria and irritating bullous eruptions on the plantar and side surfaces of her feet. She had had multiple hypopigmented spots on her skin since her early adulthood. The patient was treated with topical medication without significant improvement of symptoms. One year later she suffered a myocardial infarction, accompanied by refractory anaemia. At the age of 49, a breast cancer was diagnosed and shortly thereafter her last menstruation occurred. At age 50years, upon complaint of weight loss despite normal food intake, Hashimoto thyroiditis with latent hyperthyroidism, vitamin D insufficiency with secondary hyperparathyroidism, and poikilocytic anaemia with anisochromia, hypochromia, anisocytosis, elliptocytes, drepanocytes, dacryocytes, acanthocytes, echinocytes, schizocytes, stomatocytes and target cells were diagnosed. The osteodensitometric and laboratory examinations revealed osteoporosis with sustained elevation of urinary Dipyridinolin-crosslinks (u-Dpd), and urinary arsenic (u-As) of 500μg/l (equivalent to 0.5 parts per million-ppm, 2.5μg/mg creatinine/dl, u-As: Phosphate of 26μg/mmol; the estimated bone As:P and As/kg body weight were 500μg/g and 11.3mg/kg, respectively). Thalassemia, immunoglobinopathy and iron deficiency were excluded. Supplementation with oral vitamin D and calcium, and antiresorptive therapy with intravenous zolendronate normalised the u-Dpd, significantly decreased the urinary arsenic concentration, and cured the anemia and the urticaria. A diagnosis of osteoresorptive arsenic intoxication (ORAI) was established. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Homicidal arsenic poisoning.

    Science.gov (United States)

    Duncan, Andrew; Taylor, Andrew; Leese, Elizabeth; Allen, Sam; Morton, Jackie; McAdam, Julie

    2015-07-01

    The case of a 50-year-old man who died mysteriously after being admitted to hospital is reported. He had raised the possibility of being poisoned prior to his death. A Coroner's post-mortem did not reveal the cause of death but this was subsequently established by post-mortem trace element analysis of liver, urine, blood and hair all of which revealed very high arsenic concentrations. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  6. Mechanism of erythrocyte death in human population exposed to arsenic through drinking water.

    Science.gov (United States)

    Biswas, Debabrata; Banerjee, Mayukh; Sen, Gargi; Das, Jayanta K; Banerjee, Apurba; Sau, T J; Pandit, Sudipta; Giri, A K; Biswas, Tuli

    2008-07-01

    Arsenic contamination in drinking water is one of the biggest natural calamities, which has become an imperative threat to human health throughout the world. Abbreviation of erythrocyte lifespan leading to the development of anemia is a common sequel in arsenic exposed population. This study was undertaken to explore the mechanism of cell death in human erythrocytes during chronic arsenic exposure. Results revealed transformation of smooth discoid red cells into evaginated echinocytic form in the exposed individuals. Further distortion converted reversible echinocytes to irreversible spheroechinocytes. Arsenic toxicity increased membrane microviscosity along with an elevation of cholesterol/phospholipid ratio, which hampered the flexibility of red cell membrane and made them less deformable. Significant increase in the binding of merocyanine 540 with erythrocyte membrane due to arsenic exposure indicated disruption of lipid packing in the outer leaflet of the cell membrane resulting from altered transbilayer phospholipid asymmetry. Arsenic induced eryptosis was characterized by cell shrinkage and exposure of phosphatidylserine at the cell surface. Furthermore, metabolic starvation with depletion of cellular ATP triggered apoptotic removal of erythrocytes from circulation. Significant decrease in reduced glutathione content indicating defective antioxidant capacity was coupled with enhancement of malondialdehyde and protein carbonyl levels, which pointed to oxidative damage to erythrocyte membrane. Arsenic toxicity intervened into red cell membrane integrity eventually leading to membrane destabilization and hemoglobin release. The study depicted the involvement of both erythrophagocytosis and hemolysis in the destruction of human erythrocytes during chronic arsenic exposure.

  7. Arsenical poisoning of fruit trees

    Energy Technology Data Exchange (ETDEWEB)

    Headden, W.P.

    1910-01-01

    Corrosive arsenical poisoning attacks the tree at the crown, below the surface of the soil and usually involves the large roots also. Pear and apple trees are affected; the pear tree is, at least, as susceptible to the action of the arsenic as the apple tree. Some varieties of pears, as well as apples, seem more susceptible than others, but this is true only in a general way. The age of the tree at the time the first applications were made seems to have some effect upon the resisting power of the bark. The variety of soil may have some influence but it is not pronounced enough to be recognized with certainty. The first sign of trouble in the apple tree is an early ripening of the leaves, at least, one year before the death of the tree; in pear trees the foilage ripens early and assumes a deep purple color. The amount of arsenic present in the destroyed bark and in the woody tissues of such trees is as great as in cases in which it is known that arsenic was the cause of death. The trouble is very general throughout the state and occurs in all kinds of soils which fact eliminates the question of seepage and, to a large extent, that of alkalis. In the case of trees which have not been sprayed but which have been grown as fillers in sprayed orchards, the wood contained arsenic. This is true, too, of young trees grown in soil which contains arsenic. This shows that the arsenic may be taken up with the nitrient solutions. The fruit grown on such trees, apples and pears, contain arsenic and also the leaves. The fruit and leaves grow and are shed each season; this is not the case with the woody portions of the tree. Systemic poisoning is produced by this arsenic distributed throughout the tree, interfering with nutrition and growth of the three and in some cases causing its death.

  8. The relationships between arsenic methylation and both skin lesions and hypertension caused by chronic exposure to arsenic in drinking water.

    Science.gov (United States)

    Wei, Binggan; Yu, Jiangping; Wang, Jing; Yang, Linsheng; Li, Hairong; Kong, Chang; Xia, Yajuan; Wu, Kegong

    2017-07-01

    The associations between arsenic exposure, arsenic methylation, and the prevalence of skin lesions and hypertension are investigated. The results indicate that the HS (hypertension and skin lesions) group and the S (skin lesions) group have higher urinary concentrations of iAs (inorganic arsenic), MMA (monomethylarsonic acid), DMA (dimethylarsinous acid) and%MMA, and lower SMI (secondary arsenic methylation index) compared to the H (hypertension) and N (without both hypertension and skin lesions) groups. The arsenic content in water which caused H may be lower than that which caused HS and S. In addition, the odds ratios suggest that higher urinary concentrations of iAs and MMA, %iAs, %MMA and PMI elevate the prevalence of only hypertension and skin lesions, and both hypertension and skin lesions. However, higher%DMA and SMI, and lower%MMA increase the prevalence of both hypertension and skin lesions compared to that of only skin lesions. It can be concluded that skin lesions subjects have higher prevalence of hypertension. Hypertension subjects may have higher prevalence of skin lesions. Lower%DMA and SMI, higher%iAs, %MMA and PMI enhance the prevalence of only hypertension and skin lesions, and both hypertension and skin lesions. Moreover, iAs and MMA may have higher toxicity and lead to both hypertension and skin lesions than to only hypertension. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Effect of reactive bed mineralogy on arsenic retention and permeability of synthetic arsenic-containing acid mine drainage.

    Science.gov (United States)

    Liu, Jing; Cheng, Hongfei; Zhao, Fenghua; Dong, Faqing; Frost, Ray L

    2013-03-15

    Successive alkalinity producing systems (SAPSs) are widely used for treating acid mine drainage (AMD) and alleviating clogging commonly occurring in limestone systems due to an amorphous ferric precipitate. In this study, iron dust, bone char, micrite and their admixtures were used to treat arsenic-containing AMD. A particular interest was devoted to arsenic removal performance, mineralogical constraints on arsenic retention ability and permeability variation during column experiment for 140 days. The results showed that the sequence of the arsenic removal capacity was as follows: bone char > micrite > iron dust. The combination of 20% v/v iron dust and 80% v/v bone char/micrite columns can achieve better hydraulic conductivity and phosphorus-retention capacity than single micrite and bone char columns. The addition of iron dust created reductive environment and resulted in the transformation of coating material from colloidal phase to secondary mineral phase, such as green rust and phosphoerrite, which obviously ameliorates hydraulic conductivity of systems. The sequential extraction experiments indicated that the stable fractions of arsenic in columns were enhanced with help of iron dust compared to single bone char and micrite columns. A combination of iron dust and micrite/bone char represented a potential SAPS for treating As-containing AMD. Copyright © 2012 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    Arsenic (+3 oxidation state) methyltransferase (As3mt) catalyzes methylation of inorganic arsenic producing a number of methylated arsenic metabolites. Although methylation has been commonly considered a pathway for detoxification of arsenic, some highly reactive methylated ars...

  11. Dietary Arsenic Exposure in Bangladesh

    National Research Council Canada - National Science Library

    Molly L. Kile; E. Andres Houseman; Carrie V. Breton; Thomas Smith; Quazi Quamruzzaman; Mahmuder Rahman; Golam Mahiuddin; David C. Christiani

    2007-01-01

    Background: Millions of people in Bangladesh are at risk of chronic arsenic toxicity from drinking contaminated groundwater, but little is known about diet as an additional source of As exposure. Methods...

  12. Arsenic trioxide synergistically enhances radiation response in human cervical cancer cells through ROS-dependent p38 MAPK and JNK signalling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Young-Hee; Park, Seung-Moo; Kim, Min-Jeong [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)] (and others)

    2006-07-01

    Many factors affect susceptibility of tumor cells to ionizing radiation. Among them intrinsic apoptosis sensitivity or resistancy seems to play an important role. The use of chemical modifiers as radiosensitizers in combination with low-dose irradiation may increase the therapeutic efficacy by overcoming a high apoptotic threshold. Several recent studies demonstrated additive effects of As{sub 2}O{sub 3} with conventional chemotherapeutic agents such as cisplatin, adriamycin, and etoposide, but no synergism. Previously, we have shown for the first time that As{sub 2}O{sub 3} sensitize human cervical cancer cells to ionizing radiation. Treatment of As{sub 2}O{sub 3} in combination of ionizing radiation has synergistic effects in decreasing clonogenic survival and in the regression of tumor growth in xenografts. We also have shown that the combination treatment enhanced apoptotic cell death through a reactive oxygen species-dependent pathway in human cervical cancer cells. In this study, we investigated the regulatory mechanism of ROS-mediated mitochondrial apoptotic cell death induced by combination treatment with As{sub 2}O{sub 3} and ionizing radiation in human cervical cancer cells.

  13. 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.

  14. 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...

  15. On the arsenic source mobilisation and its natural enrichment in the sediments of a high mountain cirque in the Pyrenees.

    Science.gov (United States)

    Zaharescu, Dragos George; Hooda, Peter S; Fernandez, Javier; Soler, Antonio Palanca; Burghelea, Carmen Ionela

    2009-11-01

    Recently arsenic contamination and its environmental and human health problems have been raising concerns worldwide. The occurrence of natural high levels of arsenic contamination has generally been reported for low altitude environments. Here we report a study conducted to assess the extent of arsenic mobilisation/transportation from previously identified arsenic source areas in a high altitude cirque of the Pyrenees as well as the potential contribution of As by snow. The concentration of arsenic in sediments of several tributaries was enriched up to about ten folds due to mobilisation of arsenic from the source areas within the catchment. The highest arsenic enrichments were found in an area dominated by quartzite and slate formation in the southern side of the basin, and it generally diminished towards the major lake downstream, possible due to mixing with sediments from non-source areas. At these sites arsenic exceeded the hazard quotient (HQ) limits for the protection of aquatic life. The potential hazard of the As-enriched sediments may be further enhanced outside the catchment as samples collected downstream the cirque have also shown arsenic concentration exceeding HQ unity. The arsenic concentrations in the water collected at a number of sites exceeded its guide value for the protection of aquatic life. The potential As contribution by snow in the area was low and was largely of lithospheric origin. The PCA analysis showed strong association of arsenic in sediments with the sediment mineralogical composition (Fe2O3, TiO2 and Mn). Arsenic in water was positively correlated with its concentration in the sediments and could potentially increase if the environmental/climate conditions change.

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

    Energy Technology Data Exchange (ETDEWEB)

    Li, Changzhao; Srivastava, Ritesh K.; Elmets, Craig A.; Afaq, Farrukh; Athar, Mohammad, E-mail: mathar@uab.edu

    2013-09-06

    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.

  17. 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.

  18. 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.

    2013-01-01

    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…

  19. A systematic study on extraction of total arsenic from down-scaled sample sizes of plant tissues and implications for arsenic species analysis.

    Science.gov (United States)

    Schmidt, Anne-Christine; Haufe, Nora; Otto, Matthias

    2008-09-15

    An easily feasible, species-conserving and inexpensive protocol for the extraction of total arsenic and arsenic species from terrestrial plants was designed and applied to the investigation of accumulation and metabolization of arsenite (As(III)), arsenate (As(V)), monomethylarsonate (MMA(V)), and dimethylarsinate (DMA(V)) by the model plant Tropaeolum majus. In contrast to existing extraction methods hazardous additives and elaborate procedures to enhance the extraction yields were omitted. The proposed protocol is suited to down-scale the sample sizes used for the extractions and to promote a compartmentally resolved analysis of the arsenic distribution within individual leaves, leaf stalks, and stems instead of the conventional extraction of pooled samples. In a two-step extraction, the high extraction efficiencies (85-92%) for arsenic achieved by phosphate buffer from larger amounts (200mg) of homogenized leaf material in a one-step extraction, could be enhanced to 94-100% in a second extraction step. A strong dependence of the arsenic extractability on the type of arsenic species accumulated in the tissue as well as on the type of the tissue (leaf, leaf stalk, stem) was found. For the extraction of 5mm long segments cut from individual leaves without previous homogenization of the plant parts yields between 75 and 93% depending on arsenic species prevailing in the cells were obtained using 1 or 10mM phosphate buffer. The total extraction and analysis protocol was validated using a standard reference material as well as by spiking experiments. The arsenic species analysis by IC/ICPMS revealed a number of nine unidentified metabolites in the plant extracts in addition to the species MMA(V), DMA(V), As(III), and As(V) that were provided to the plants during their growth phase.

  20. The socio-economics of arsenic removal

    Science.gov (United States)

    Johnston, Richard Bart; Hanchett, Suzanne; Khan, Mohidul Hoque

    2010-01-01

    Nearly an eighth of the population in Bangladesh relies on arsenic-contaminated drinking water. Arsenic-removal filters could help to reduce exposure, but their price is high for the poor and their maintenance is cumbersome.

  1. Chronic Arsenic Poisoning Following Ayurvedic Medication

    National Research Council Canada - National Science Library

    Pinto, Benzeeta; Goyal, Palvi; Flora, S J. S; Gill, K D; Singh, Surjit

    2014-01-01

    ... 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...

  2. [Influencing factors and mechanism of arsenic removal during the aluminum coagulation process].

    Science.gov (United States)

    Chen, Gui-Xia; Hu, Cheng-Zhi; Zhu, Ling-Feng; Tong, Hua-Qing

    2013-04-01

    Aluminum coagulants are widely used in arsenic (As) removal during the drinking water treatment process. Aluminium chloride (AlCl3) and polyaluminium chloride (PACl) which contains high content of Al13 were used as coagulants. The effects of aluminum species, pH, humic acid (HA) and coexisting anions on arsenic removal were investigated. Results showed that AlCl3 and PACl were almost ineffective in As(II) removal while the As(V) removal efficiency reached almost 100%. pH was an important influencing factor on the arsenic removal efficiency, because pH influenced the distribution of aluminum species during the coagulation process. The efficiency of arsenic removal by aluminum coagulants was positively correlated with the content of Al13 species. HA and some coexisting anions showed negative impact on arsenic removal because of the competitive adsorption. The negative influence of HA was more pronounced at low coagulant dosages. PO4(3-) and F(-) showed marked influence during arsenic removal, but there was no obvious influence when SiO3(2-), CO3(2-) and SO4(2-) coexisted. The present study would be helpful to direct arsenic removal by enhanced coagulation during the drinking water treatment.

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

    Science.gov (United States)

    Hasegawa, H; Rahman, M Azizur; Matsuda, T; Kitahara, T; Maki, T; Ueda, K

    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 (0.45 microm) and colloidal (10 kDa-0.45 microm) 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.

  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. Arsenic-induced plant growth of arsenic-hyperaccumulator Pteris vittata: Impact of arsenic and phosphate rock.

    Science.gov (United States)

    Han, Yong-He; Yang, Guang-Mei; Fu, Jing-Wei; Guan, Dong-Xing; Chen, Yanshan; Ma, Lena Q

    2016-04-01

    Phosphate rock (PR) has been shown to promote plant growth and arsenic (As) uptake by As-hyperaccumulator Pteris vittata (PV). However, little is known about its behaviors in agricultural soils. In this study, impact of 50 mg kg(-1) As and/or 1.5% PR amendment on plant As accumulation and growth was investigated by growing PV for 90 d in three agricultural soils. While As amendment significantly increased plant As uptake and substantially promoted PV growth, the opposite was observed with PR amendment. Arsenic amendment increased plant frond As from 16.9-265 to 961-6017 mg kg(-1),whereas PR amendment lowered frond As to 10.2-216 mg kg(-1). The As-induced plant growth stimulation was 69-71%. While PR amendment increased plant Ca and P uptake, As amendment showed opposite results. The PV biomass was highly correlated with plant As at r = 0.82, but with weak correlations with plant Ca or P at r PV growth, probably independent of Ca or P uptake, 2) PR amendment didn't enhance plant growth or As uptake by PV in agricultural soils with adequate available P, and 3) PV effluxed arsenite (AsIII) growing in agricultural soils. Published by Elsevier Ltd.

  6. 21 CFR 556.60 - Arsenic.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Arsenic. 556.60 Section 556.60 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND... New Animal Drugs § 556.60 Arsenic. Tolerances for total residues of combined arsenic (calculated as As...

  7. 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

  8. ARSENIC SEPARATION FROM WATER USING ZEOLITES

    Science.gov (United States)

    Arsenic is known to be a hazardous contaminant in drinking water. The presence of arsenic in water supplies has been linked to arsenical dermatosis and skin cancer . Zeolites are well known for their ion exchange capacities. In the present work, the potential use of a variety of ...

  9. Breast cancer, dermatofibromas and arsenic.

    Science.gov (United States)

    Dantzig, Paul I

    2009-01-01

    Dermatofibromas are common benign tumors in women, and breast cancer is the most common malignancy in women. The aim of this study is to determine if there is any relationship between the two conditions. Five patients with dermatofibromas and 10 control patients (two groups) had their skin biopsies measured for arsenic by inductively coupled mass spectrometry. Fifty randomly selected patients with breast cancer and 50 control patients were examined for the presence of dermatofibromas. The dermatofibromas were found to have an arsenic concentration of 0.171 micrograms/gram, compared with 0.06 and 0.07 micrograms/gram of the two control groups. Forty-three out of 50 patients with breast cancer had dermatofibromas and 32/50 patients with breast cancer had multiple dermatofibromas, compared to 10/50 control patients with dermatofibromas and only 1/50 with multiple dermatofibromas. Arsenic is important in the development of dermatofibromas and dermatofibromas represent a reservoir and important sign of chronic arsenic exposure. Dermatofibromas represent an important sign for women at risk for breast cancer, and arsenic may represent the cause of the majority of cases of breast cancer.

  10. Breast cancer, dermatofibromas and arsenic

    Directory of Open Access Journals (Sweden)

    Dantzig Paul

    2009-01-01

    Full Text Available Background: Dermatofibromas are common benign tumors in women, and breast cancer is the most common malignancy in women. The aim of this study is to determine if there is any relationship between the two conditions. Materials and Methods: Five patients with dermatofibromas and 10 control patients (two groups had their skin biopsies measured for arsenic by inductively coupled mass spectrometry. Fifty randomly selected patients with breast cancer and 50 control patients were examined for the presence of dermatofibromas. Results: The dermatofibromas were found to have an arsenic concentration of 0.171 micrograms/gram, compared with 0.06 and 0.07 micrograms/gram of the two control groups. Forty-three out of 50 patients with breast cancer had dermatofibromas and 32/50 patients with breast cancer had multiple dermatofibromas, compared to 10/50 control patients with dermatofibromas and only 1/50 with multiple dermatofibromas. Conclusions: Arsenic is important in the development of dermatofibromas and dermatofibromas represent a reservoir and important sign of chronic arsenic exposure. Dermatofibromas represent an important sign for women at risk for breast cancer, and arsenic may represent the cause of the majority of cases of breast cancer.

  11. 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.

  12. Mineral resource of the month: arsenic

    Science.gov (United States)

    Brooks, William E.

    2008-01-01

    Arsenic has a long and varied history: Although it was not isolated as an element until the 13th century, it was known to the ancient Chinese, Egyptians and Greeks in compound form in the minerals arsenopyrite, realgar and orpiment. In the 1400s, “Scheele’s Green” was first used as an arsenic pigment in wallpaper, and leached arsenic from wallpaper may have contributed to Napoleon’s death in 1821. The 1940s play and later movie, Arsenic and Old Lace, dramatizes the metal’s more sinister role. Arsenic continues to be an important mineral commodity with many modern applications.

  13. Arsenic behavior in newly drilled wells

    Science.gov (United States)

    Kim, M.-J.; Nriagu, J.; Haack, S.

    2003-01-01

    In the present paper, inorganic arsenic species and chemical parameters in groundwater were determined to investigate the factors related to the distribution of arsenic species and their dissolution from rock into groundwater. For the study, groundwater and core samples were taken at different depths of two newly drilled wells in Huron and Lapeer Counties, Michigan. Results show that total arsenic concentrations in the core samples varied, ranging from 0.8 to 70.7 mg/kg. Iron concentration in rock was about 1800 times higher than that of arsenic, and there was no correlation between arsenic and iron occurrences in the rock samples. Arsenic concentrations in groundwater ranged from ion, low redox potential and low dissolved oxygen supported the observed arsenic species distribution. There was no noticeable difference in the total arsenic concentration and arsenic species ratio between unfiltered and filtered (0.45 ??m) waters, indicating that the particulate form of arsenic was negligible in the groundwater samples. There were correlations between water sampling depth and chemical parameters, and between arsenic concentration and chemical parameters, however, the trends were not always consistent in both wells. ?? 2003 Elsevier Science Ltd. All rights reserved.

  14. Arsenic Release from Foodstuffs upon Food Preparation.

    Science.gov (United States)

    Cheyns, Karlien; Waegeneers, Nadia; Van de Wiele, Tom; Ruttens, Ann

    2017-03-22

    In this study the concentration of total arsenic (As) and arsenic species (inorganic As, arsenobetaine, dimethylarsinate, and methylarsonate) was monitored in different foodstuffs (rice, vegetables, algae, fish, crustacean, molluscs) before and after preparation using common kitchen practices. By measuring the water content of the foodstuff and by reporting arsenic concentrations on a dry weight base, we were able to distinguish between As release effects due to food preparation and As decrease due to changes in moisture content upon food preparation. Arsenic species were released to the broth during boiling, steaming, frying, or soaking of the food. Concentrations declined with maxima of 57% for total arsenic, 65% for inorganic As, and 32% for arsenobetaine. On the basis of a combination of our own results and literature data, we conclude that the extent of this release of arsenic species is species specific, with inorganic arsenic species being released most easily, followed by the small organic As species and the large organic As species.

  15. 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.

  16. Speciation analysis of arsenic in terrestrial plants from arsenic contaminated area.

    Science.gov (United States)

    Jedynak, Lukasz; Kowalska, Joanna; Harasimowicz, Joanna; Golimowski, Jerzy

    2009-01-01

    Arsenic speciation analysis was carried out in plants collected from arsenic contaminated area. Two plant species were chosen for the investigation: Reed Grass (Calamagrostis arundinacea) and Lady Fern (Athyrium filix-femina). To characterize arsenic species several different extraction procedures were applied including enzymatic extraction and extraction using surfactant solution (SDS). Two-step sequential extraction (water+SDS) that assures the highest extraction efficiency was applied to extract arsenic species from plant material. HPLC with anion-exchange column was used to separate extracted arsenic compounds and ICP-MS was applied for quantitative arsenic determination after species separation.

  17. Arsenic bioleaching in medical realgar ore and arsenic- bearing ...

    African Journals Online (AJOL)

    Wu XH, Sun DH, Zhuang ZX, Wang XR, Gong HF, Hong. JX, Lee FSC. Analysis and leaching characteristics of mercury and arsenic in Chinese medicinal material. Anal. Chim Acta 2002; 2: 311-323. 6. Ning N, Peng Z, Yuan L, Gou B, Zhang T, Wang K. Realgar nano-particles induce apoptosis and necrosis in leukemia cell ...

  18. 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

  19. 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.

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

    Science.gov (United States)

    Gao, Jianwei; Yu, Jiangping; Yang, Linsheng

    2011-01-01

    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. PMID:21776214

  1. Magentite nanoparticle for arsenic remotion.

    Science.gov (United States)

    Viltres, H.; Odio, O. F.; Borja, R.; Aguilera, Y.; Reguera, E.

    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 (water. Magnetic nanoparticles (magnetite) were prepared using a co-precipitation method with FeCl3 and FeCl2 as metal source and NaOH aqueous solution as precipitating agent. Magnetite nanoparticles synthesized were put in contact with As2O3 and As2O5 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.

  2. Acute arsenic poisoning diagnosed late.

    Science.gov (United States)

    Shumy, Farzana; Anam, Ahmad Mursel; Kamruzzaman, A K M; Amin, Md Robed; Chowdhury, M A Jalil

    2016-04-01

    Acute arsenicosis, although having a 'historical' background, is not common in our times. This report describes a case of acute arsenic poisoning, missed initially due to its gastroenteritis-like presentation, but suspected and confirmed much later, when the patient sought medical help for delayed complications after about 2 months. © The Author(s) 2015.

  3. [Arsenic poisoning: a special gastroenteritis...].

    Science.gov (United States)

    Ganster, F; Kuteifan, K; Mootien, Y; Harry, P; Guiot, P

    2009-06-01

    Arsenic (As) intoxication is nowadays extremely rare. Two cases of acute and chronic As criminal poisoning leading to death of a couple of retired people, are reported. Clinical presentation was simulating a gastro-enteritidis with fast evolution to refractory shock. Toxicological analysis confirmed this diagnostic, with respectively blood As concentrations at 579 and 21 765 microg/l for our two patients.

  4. Cellular arsenic transport pathways in mammals.

    Science.gov (United States)

    Roggenbeck, Barbara A; Banerjee, Mayukh; Leslie, Elaine M

    2016-11-01

    Natural contamination of drinking water with arsenic results in the exposure of millions of people world-wide to unacceptable levels of this metalloid. This is a serious global health problem because arsenic is a Group 1 (proven) human carcinogen and chronic exposure is known to cause skin, lung, and bladder tumors. Furthermore, arsenic exposure can result in a myriad of other adverse health effects including diseases of the cardiovascular, respiratory, neurological, reproductive, and endocrine systems. In addition to chronic environmental exposure to arsenic, arsenic trioxide is approved for the clinical treatment of acute promyelocytic leukemia, and is in clinical trials for other hematological malignancies as well as solid tumors. Considerable inter-individual variability in susceptibility to arsenic-induced disease and toxicity exists, and the reasons for such differences are incompletely understood. Transport pathways that influence the cellular uptake and export of arsenic contribute to regulating its cellular, tissue, and ultimately body levels. In the current review, membrane proteins (including phosphate transporters, aquaglyceroporin channels, solute carrier proteins, and ATP-binding cassette transporters) shown experimentally to contribute to the passage of inorganic, methylated, and/or glutathionylated arsenic species across cellular membranes are discussed. Furthermore, what is known about arsenic transporters in organs involved in absorption, distribution, and metabolism and how transport pathways contribute to arsenic elimination are described. Copyright © 2016. Published by Elsevier B.V.

  5. Health effects of chronic arsenic exposure.

    Science.gov (United States)

    Hong, Young-Seoub; Song, Ki-Hoon; Chung, Jin-Yong

    2014-09-01

    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.

  6. 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.

  7. 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

  8. 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

  9. Arsenic K-edge X-ray absorption spectroscopy of arsenic in seafood.

    Science.gov (United States)

    George, Graham N; Prince, Roger C; Singh, Satya P; Pickering, Ingrid J

    2009-05-01

    It is well known that seafood contains high levels of arsenic. For marine animals arsenic is predominantly present as arsenobetaine and related compounds which are not metabolized and are thought to present no toxic hazard to humans. With edible seaweeds, arsenic is present in different forms, of which arsenosugars are the best known. These species may be metabolized by mammals, and the high arsenic contents of these materials represent a significant environmental source for human exposure to arsenicals in some populations. In this work, we explore the utility of As K-edge X-ray absorption near-edge spectroscopy as an in situ probe of the chemical forms of arsenic in seaweeds. We find that three different chemical types of arsenic are present, consistent with arsenate, an arsenosugar or tetra-alkyl-arsonium species, and a trivalent arsenic species.

  10. [Biological effects of arsenic and diseases: The mechanisms involved in arsenic-induced carcinogenesis].

    Science.gov (United States)

    Suzuki, Takehiro; Takumi, Shota; Okamura, Kazuyuki; Nohara, Keiko

    2016-07-01

    Chronic arsenic exposure is associated with many diseases, including cancers. Our study using in vivo assay in gpt-delta transgenic mice showed that arsenic particularly induces G : C to T : A transversions, a mutation type induced through oxidative-stress-induced 8-OHdG formation. Gestational arsenic exposure of C3H mice was reported to increase hepatic tumor incidence. We showed that gestational arsenic exposure increased hepatic tumors having activated oncogene Ha-ras by C to A mutation. We also showed that DNA methylation status of Fosb region is implicated in tumor augmentation by gestational arsenic exposure. We further showed that long-term arsenic exposure induces premature senescence. Recent studies reported that senescence is involved in not only tumor suppression, but also tumorgenesis. All these effects of arsenic might be involved in arsenic-induced carcinogenesis.

  11. Arsenic exposure from drinking water, arsenic methylation capacity, and carotid intima-media thickness in Bangladesh

    National Research Council Canada - National Science Library

    Chen, Yu; Wu, Fen; Graziano, Joseph H; Parvez, Faruque; Liu, Mengling; Paul, Rina Rani; Shaheen, Ishrat; Sarwar, Golam; Ahmed, Alauddin; Islam, Tariqul; Slavkovich, Vesna; Rundek, Tatjana; Demmer, Ryan T; Desvarieux, Moise; Ahsan, Habibul

    2013-01-01

    We conducted a cross-sectional study to evaluate the interrelationships between past arsenic exposure, biomarkers specific for susceptibility to arsenic exposure, and carotid intima-media thickness (cIMT...

  12. The role of chelation in the treatment of arsenic and mercury poisoning.

    Science.gov (United States)

    Kosnett, Michael J

    2013-12-01

    Chelation for heavy metal intoxication began more than 70 years ago with the development of British anti-lewisite (BAL; dimercaprol) in wartime Britain as a potential antidote the arsenical warfare agent lewisite (dichloro[2-chlorovinyl]arsine). DMPS (unithiol) and DMSA (succimer), dithiol water-soluble analogs of BAL, were developed in the Soviet Union and China in the late 1950s. These three agents have remained the mainstay of chelation treatment of arsenic and mercury intoxication for more than half a century. Animal experiments and in some instances human data indicate that the dithiol chelators enhance arsenic and mercury excretion. Controlled animal experiments support a therapeutic role for these chelators in the prompt treatment of acute poisoning by arsenic and inorganic mercury salts. Treatment should be initiated as rapidly as possible (within minutes to a few hours), as efficacy declines or disappears as the time interval between metal exposure and onset of chelation increases. DMPS and DMSA, which have a higher therapeutic index than BAL and do not redistribute arsenic or mercury to the brain, offer advantages in clinical practice. Although chelation following chronic exposure to inorganic arsenic and inorganic mercury may accelerate metal excretion and diminish metal burden in some organs, potential therapeutic efficacy in terms of decreased morbidity and mortality is largely unestablished in cases of chronic metal intoxication.

  13. Metabolic interrelationships between arsenic and selenium.

    Science.gov (United States)

    Levander, O A

    1977-08-01

    In 1938, Moxon discovered that arsenic protected against selenium toxicity. Since that time it has been shown that this protective effect of arsenic against selenium poisoning can be demonstrated in many different animal species under a wide variety of conditions. Antagonistic effects between arsenic and selenium have also been noted in teratologic experiments. Early metabolic studies showed that arsenic inhibited the expiration of volatile selenium compounds by rats injected with acutely toxic doses of both elements. This was puzzling since pulmonary excretion had long been regarded as a means by which animals could rid themselves of excess selenium. However, later work demonstrated that arsenic increased the biliary excretion of selenium. Not only did arsenic stimulate the excretion of selenium in the bile, but selenium also stimulated the excretion of arsenic in the bile. This increased biliary excretion of selenium caused by arsenic provides a reasonable rationale for the ability of arsenic to counteract the toxicity of selenium, although the chemical mechanism by which arsenic does this is not certain. The most satisfactory explanation is that these two elements react in the liver to form a detoxication conjugate which is then excreted into the bile. This is consistent with the fact that both arsenic and selenium each increase the biliary excretion of the other. Several other metabolic interactions between arsenic and selenium have been demonstrated in vitro, but their physiological significance is not clear. Although arsenic decreased selenium toxicity under most conditions, there is a pronounced synergistic toxicity between arsenic and two methylated selenium metabolites, trimethylselenonium ion or dimethyl selenide. The ecological consequences of these synergisms are largely unexplored, although it is likely that selenium methylation occurs in the environment. All attempts to promote or prevent selenium deficiency diseases in animals by feeding arsenic have

  14. 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 1425/106. 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.

  15. 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

  16. Aberrant DNA methylation and gene expression in livers of newborn mice transplacentally exposed to a hepatocarcinogenic dose of inorganic arsenic

    Science.gov (United States)

    Xie, Yaxiong; Liu, Jie; Benbrahim-Tallaa, Lamia; Ward, Jerry M.; Logsdon, Daniel; Diwan, Bhalchandra A.; Waalkes, Michael P.

    2008-01-01

    Our prior work showed that brief exposure of pregnant C3H mice to inorganic arsenic-induced hepatocellular carcinoma (HCC) formation in adult male offspring. The current study examined the early hepatic events associated with this oncogenic transformation. Pregnant mice were exposed to a known carcinogenic dose of arsenic (85 ppm) in the drinking water from gestation days 8 to 18. The dams were allowed to give birth and liver samples from newborn males were analyzed for arsenic content, global DNA methylation and aberrant expression of genes relevant to the carcinogenic process. Arsenic content in newborn liver reached 57 ng/g wet weight, indicating arsenic had crossed the placenta, reached the fetal liver and that significant amounts remained after birth. Global methylation status of hepatic DNA was not altered by arsenic in the newborn. However, a significant reduction in methylation occurred globally in GC-rich regions. Microarray and real-time RT-PCR analysis showed that arsenic exposure enhanced expression of genes encoding for glutathione production and caused aberrant expression of genes related to insulin growth factor signaling pathways and cytochrome P450 enzymes. Other expression alterations observed in the arsenic-treated male mouse newborn liver included the overexpression of cdk-inhibitors and stress response genes including increased expression of metallothionein-1 and decreased expression of betaine-homocysteine methyltransferase and thioether S-methyltransferase. Thus, transplacental exposure to arsenic at a hepatocarcinogenic dose induces alterations in DNA methylation and a complex set of aberrant gene expressions in the newborn liver, a target of arsenic carcinogenesis. PMID:17451858

  17. 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

  18. Effects of arsenic on osteoblast differentiation in vitro and on bone mineral density and microstructure in rats.

    Science.gov (United States)

    Wu, Cheng-Tien; Lu, Tung-Ying; Chan, Ding-Cheng; Tsai, Keh-Sung; Yang, Rong-Sen; Liu, Shing-Hwa

    2014-06-01

    Arsenic is a ubiquitous toxic element and is known to contaminate drinking water in many countries. Several epidemiological studies have shown that arsenic exposure augments the risk of bone disorders. However, the detailed effect and mechanism of inorganic arsenic on osteoblast differentiation of bone marrow stromal cells and bone loss still remain unclear. We investigated the effects and mechanism of arsenic on osteoblast differentiation in vitro and evaluated bone mineral density (BMD) and bone microstructure in rats at doses relevant to human exposure from drinking water. We used a cell model of rat primary bone marrow stromal cells (BMSCs) and a rat model of long-term exposure with arsenic-contaminated drinking water, and determined bone microstructure and BMD in rats by microcomputed tomography (μCT). We observed significant attenuation of osteoblast differentiation after exposure of BMSCs to arsenic trioxide (0.5 or 1 μM). After arsenic treatment during differentiation, expression of runt-related transcription factor-2 (Runx2), bone morphogenetic protein-2 (BMP-2), and osteocalcin in BMSCs was inhibited and phosphorylation of enhanced extracellular signal-regulated kinase (ERK) was increased. These altered differentiation-related molecules could be reversed by the ERK inhibitor PD98059. Exposure of rats to arsenic trioxide (0.05 or 0.5 ppm) in drinking water for 12 weeks altered BMD and microstructure, decreased Runx2 expression, and increased ERK phosphorylation in bones. In BMSCs isolated from arsenic-treated rats, osteoblast differentiation was inhibited. Our results suggest that arsenic is capable of inhibiting osteoblast differentiation of BMSCs via an ERK-dependent signaling pathway and thus increasing bone loss.

  19. Oxidative stress and hepatic stellate cell activation are key events in arsenic induced liver fibrosis in mice

    Science.gov (United States)

    Ghatak, Subhadip; Biswas, Ayan; Dhali, Gopal Krishna; Chowdhury, Abhijit; Boyer, James L.; Santra, Amal

    2013-01-01

    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. PMID:21134390

  20. 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.

  1. 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.

  2. Natural Antioxidants Against Arsenic-Induced Genotoxicity.

    Science.gov (United States)

    Kumar, Munesh; Lalit, Minakshi; Thakur, Rajesh

    2016-03-01

    Arsenic is present in water, soil, and air in organic as well as in inorganic forms. However, inorganic arsenic is more toxic than organic and can cause many diseases including cancers in humans. Its genotoxic effect is considered as one of its carcinogenic actions. Arsenic can cause DNA strand breaks, deletion mutations, micronuclei formation, DNA-protein cross-linking, sister chromatid exchange, and DNA repair inhibition. Evidences indicate that arsenic causes DNA damage by generation of reactive free radicals. Nutritional supplementation of antioxidants has been proven highly beneficial against arsenic genotoxicity in experimental animals. Recent studies suggest that antioxidants protect mainly by reducing excess free radicals via restoring the activities of cellular enzymatic as well as non-enzymatic antioxidants and decreasing the oxidation processes such as lipid peroxidation and protein oxidation. The purpose of this review is to summarize the recent literature on arsenic-induced genotoxicity and its mitigation by naturally derived antioxidants in various biological systems.

  3. Removal of arsenic from drinking water

    OpenAIRE

    Simonič, Marjana

    2015-01-01

    The drinking water well in Slovenska Bistrica, Slovenia, contains arsenic in concentration around 50 ?$/mu$?g/L. Therefore it is necessary to implement a technological treatment to make the water suitable for drinking. In order to do so the following technologies were suggested: activated alumina, green sand, granular ferric hydroxide and special goethite media. They were all carried out on a laboratory scale. We managed to remove arsenic below 1 ?$/mu$?g/L. Arsenic is usually found as an ani...

  4. Arsenic-induced suicidal erythrocyte death

    Energy Technology Data Exchange (ETDEWEB)

    Mahmud, Hasan; Foeller, Michael; Lang, Florian [University of Tuebingen (Germany). Department of Physiology

    2009-02-15

    Environmental exposure to arsenic has been associated with anemia, which could result from suicidal erythrocyte death or eryptosis, characterized by cell shrinkage and phosphatidylserine exposure at the erythrocyte surface. Eryptosis is triggered by increase in cytosolic Ca{sup 2+} concentration, ceramide and energy depletion. The present experiments explored, whether arsenic stimulates eryptosis. According to annexin V-binding, arsenic trioxide (7{mu}M) within 48 h significantly increased phosphatidylserine exposure of human erythrocytes without inducing hemolysis. According to forward scatter, arsenic trioxide (7{mu}M) significantly decreased cell volume. Moreover, Fluo3-fluorescence showed that arsenic (10 {mu}M) significantly increased cytosolic Ca{sup 2+} concentration. According to binding of respective fluorescent antibodies, arsenic trioxide (10{mu}M) significantly increased ceramide formation. Arsenic (10{mu}M) further lowered the intracellular ATP concentration. Removal of extracellular Ca{sup 2+} or inhibition of the Ca{sup 2+}-permeable cation channels with amiloride blunted the effects of arsenic on annexin V-binding and cell shrinkage. In conclusion, arsenic triggers suicidal erythrocyte death by increasing cytosolic Ca{sup 2+} concentration, by stimulating the formation of ceramide and by decreasing ATP availability. (orig.)

  5. 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

  6. 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.

  7. 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.

  8. Industrial contributions of arsenic to the environment.

    Science.gov (United States)

    Nelson, K W

    1977-08-01

    Arsenic is present in all copper, lead, and zinc sulfide ores and is carried along with those metals in the mining, milling and concentrating process. Separation, final concentration and refining of by-product arsenic as the trioxide is achieved at smelters. Arsenic is the essential consistent element of many compounds important and widely used in agriculture and wood preservation. Lesser amounts are used in metal alloys, glass-making, and feed additives. There is no significant recycling. Current levels of arsenic emissions to the atmosphere from smelters and power plants and ambient air concentrations are given as data of greatest environmental interest.

  9. 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.

  10. 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.

  11. BREAST CANCER, DERMATOFIBROMAS AND ARSENIC

    OpenAIRE

    Dantzig Paul

    2009-01-01

    Background: Dermatofibromas are common benign tumors in women, and breast cancer is the most common malignancy in women. The aim of this study is to determine if there is any relationship between the two conditions. Materials and Methods: Five patients with dermatofibromas and 10 control patients (two groups) had their skin biopsies measured for arsenic by inductively coupled mass spectrometry. Fifty randomly selected patients with breast cancer and 50 control patients were examined for...

  12. [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.

  13. 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.

  14. Ultramafic-derived arsenic in a fractured bedrock aquifer

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, Peter C., E-mail: pryan@middlebury.edu [Geology Department, Middlebury College, 276 Bicentennial Way, Middlebury, VT 05753 (United States); Kim, Jonathan [Vermont Geological Survey, Waterbury, VT 05671 (United States); Wall, Andrew J. [Department of Geosciences, Penn State University, University Park, PA 16802 (United States); Moen, Jonathan C.; Corenthal, Lilly G.; Chow, Daniel R.; Sullivan, Colleen M.; Bright, Kevin S. [Geology Department, Middlebury College, 276 Bicentennial Way, Middlebury, VT 05753 (United States)

    2011-04-15

    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{sub 3}{sup -} concentrations.

  15. Arsenic Removal by Liquid Membranes

    Directory of Open Access Journals (Sweden)

    Tiziana Marino

    2015-03-01

    Full Text Available Water contamination with harmful arsenic compounds represents one of the most serious calamities of the last two centuries. Natural occurrence of the toxic metal has been revealed recently for 21 countries worldwide; the risk of arsenic intoxication is particularly high in Bangladesh and India but recently also Europe is facing similar problem. Liquid membranes (LMs look like a promising alternative to the existing removal processes, showing numerous advantages in terms of energy consumption, efficiency, selectivity, and operational costs. The development of different LM configurations has been a matter of investigation by several researching groups, especially for the removal of As(III and As(V from aqueous solutions. Most of these LM systems are based on the use of phosphine oxides as carriers, when the metal removal is from sulfuric acid media. Particularly promising for water treatment is the hollow fiber supported liquid membrane (HFSLM configuration, which offers high selectivity, easy transport of the targeted metal ions, large surface area, and non-stop flow process. The choice of organic extractant(s plays an essential role in the efficiency of the arsenic removal. Emulsion liquid membrane (ELM systems have not been extensively investigated so far, although encouraging results have started to appear in the literature. For such LM configuration, the most relevant step toward efficiency is the choice of the surfactant type and its concentration.

  16. 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)

  17. 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.

  18. 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.

  19. 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.

  20. Inorganic Arsenic and Human Prostate Cancer

    Science.gov (United States)

    Benbrahim-Tallaa, Lamia; Waalkes, Michael P.

    2008-01-01

    Objective We critically evaluated the etiologic role of inorganic arsenic in human prostate cancer. Data sources We assessed data from relevant epidemiologic studies concerning environmental inorganic arsenic exposure. Whole animal studies were evaluated as were in vitro model systems of inorganic arsenic carcinogenesis in the prostate. Data synthesis Multiple studies in humans reveal an association between environmental inorganic arsenic exposure and prostate cancer mortality or incidence. Many of these human studies provide clear evidence of a dose–response relationship. Relevant whole animal models showing a relationship between inorganic arsenic and prostate cancer are not available. However, cellular model systems indicate arsenic can induce malignant transformation of human prostate epithelial cells in vitro. Arsenic also appears to impact prostate cancer cell progression by precipitating events leading to androgen independence in vitro. Conclusion Available evidence in human populations and human cells in vitro indicates that the prostate is a target for inorganic arsenic carcinogenesis. A role for this common environmental contaminant in human prostate cancer initiation and/or progression would be very important. PMID:18288312

  1. 29 CFR 1915.1018 - Inorganic arsenic.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Inorganic arsenic. 1915.1018 Section 1915.1018 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... § 1915.1018 Inorganic arsenic. Note: The requirements applicable to shipyard employment under this...

  2. 29 CFR 1926.1118 - Inorganic arsenic.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Inorganic arsenic. 1926.1118 Section 1926.1118 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... Inorganic arsenic. Note: The requirements applicable to construction work under this section are identical...

  3. Arsenic Consumption in the United States.

    Science.gov (United States)

    Wilson, Denise

    2015-10-01

    Exposure limits for arsenic in drinking water and minimal risk levels (MRLs) for total dietary exposure to arsenic have long been established in the U.S. Multiple studies conducted over the last five years have detected arsenic in foods and beverages including juice, rice, milk, broth (beef and chicken), and others. Understanding whether or not each of these foods or drinks is a concern to certain groups of individuals requires examining which types of and how much arsenic is ingested. In this article, recent studies are reviewed and placed in the context of consumption patterns. When single sources of food or drink are considered in isolation, heavy rice eaters can be exposed to the most arsenic among adults while infants consuming formula containing contaminated organic brown rice syrup are the most exposed group among children. Most food and drink do not contain sufficient arsenic to exceed MRLs. For individuals consuming more than one source of contaminated water or food, however, adverse health effects are more likely. In total, recent studies on arsenic contamination in food and beverages emphasize the need for individual consumers to understand and manage their total dietary exposure to arsenic.

  4. Arsenic Species in the Ground Water

    Science.gov (United States)

    Abstract Arsenic concentrations in ground varies widely and regionally across the United States and exists as oxyanions having two oxidation states: As(+III) and As(+V). As(V) is effectively removed by most arsenic treatment processes whereas uncharged As(III) is poorly removed...

  5. 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

  6. Ecotoxicology of arsenic in the hydrosphere: Implications for public ...

    African Journals Online (AJOL)

    Arsenic is a naturally occurring metalloid element that is found in soil, air and water. Environmental arsenic exists in both organic and inorganic states. Organic arsenicals are generally considered non toxic, whereas inorganic forms are toxic. The most acutely toxic form is arsine gas. Inorganic arsenic exists predominantly in ...

  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. Heteronuclear compounds of arsenic and antimony

    Science.gov (United States)

    Mauser, James E.

    1982-09-01

    Volatilization of secondary metals such as arsenic, antimony, and bismuth, during the smelting of copper ores, is important because of environmental and resource considerations. The Bureau of Mines, United States Department of the Interior, has been studying copper concentrate roasting in conjunction with the volatility of these minor constituents. Some unusual vaporization behavior initiated this supplemental paper which shows that when the mixed sulfides of arsenic and antimony are heated, the volatilization of arsenic is retarded and the volatilization of antimony increased. Mixed oxides of arsenic and antimony also exhibit exceptional volatilization behavior. These anomalous vaporization behaviors are attributed to the formation of heteronuclear compounds of arsenic and antimony, but the colligative properties of solutions may also be a factor.

  9. 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.

  10. Efficacy of crude extract of Emblica officinalis (amla) in arsenic-induced oxidative damage and apoptosis in splenocytes of mice

    Science.gov (United States)

    Singh, Manish Kumar; Yadav, Suraj Singh; Yadav, Rajesh Singh; Singh, Uma Shanker; Shukla, Yogeshwar; Pant, Kamlesh Kumar; Khattri, Sanjay

    2014-01-01

    Introduction: Arsenic, an environmental contaminant naturally occurred in groundwater and has been found to be associated with immune-related health problems in humans. Objective: In view of increasing risk of arsenic exposure due to occupational and non-occupational settings, the present study has been focused to investigate the protective efficacy of amla against arsenic-induced spleenomegaly in mice. Results: Arsenic exposures (3 mg/kg body weight p.o for 30 days) in mice caused an increase production of ROS (76%), lipid peroxidation (84%) and decrease in the levels of superoxide dismutase (53%) and catalase (54%) in spleen as compared to controls. Arsenic exposure to mice also caused a significant increase in caspases-3 activity (2.8 fold) and decreases cell viability (44%), mitochondrial membrane potential (47%) linked with apoptosis assessed by the cell cycle analysis (subG1-28.72%) and annexin V/PI binding in spleen as compared to controls. Simultaneous treatment of arsenic and amla (500 mg/kg body weight p.o for 30 days) in mice decreased the levels of lipid peroxidation (33%), ROS production (24%), activity of caspase-3 (1.4 fold), apoptosis (subG1 12.72%) and increased cell viability (63%), levels superoxide dismutase (80%), catalase (77%) and mitochondrial membrane potential (66%) as compared to mice treated with arsenic alone. Conclusions: Results of the present study indicate that the effect of arsenic is mainly due to the depletion of glutathione in liver associated with enhanced oxidative stress that has been found to be protected following simultaneous treatment of arsenic and amla. PMID:24748729

  11. Arsenic pesticides and environmental pollution: exposure, poisoning, hazards and recommendations.

    Science.gov (United States)

    El-Bahnasawy, Mamdouh M; Mohammad, Amina El-Hosini; Morsy, Tosson A

    2013-08-01

    Arsenic is a metalloid element. Acute high-dose exposure to arsenic can cause severe systemic toxicity and death. Lower dose chronic arsenic exposure can result in subacute toxicity that can include peripheral sensorimotor neuropathy, skin eruptions, and hepatotoxicity. Long-term effects of arsenic exposure include an in Due to the physiologic effects of the arsenic on all body systems, thus, chronic arsenic-poisoned patient is a major nursing challenge. The critical care nurse provides valuable assessment and interventions that prevent major multisystem complications from arsenic toxicity.

  12. 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.

  13. 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.

  14. Prenatal arsenic exposure, child marriage, and pregnancy weight gain: Associations with preterm birth in Bangladesh.

    Science.gov (United States)

    Rahman, Mohammad L; Kile, Molly L; Rodrigues, Ema G; Valeri, Linda; Raj, Anita; Mazumdar, Maitreyi; Mostofa, Golam; Quamruzzaman, Quazi; Rahman, Mahmudur; Hauser, Russ; Baccarelli, Andrea; Liang, Liming; Christiani, David C

    2017-12-12

    Preterm birth is a disease of multifactorial etiologies that has environmental, social, and maternal health components. Individual studies have shown that exposure to arsenic contaminated drinking water, child marriage, and low maternal weight gain during pregnancy contribute to preterm birth. These factors are highly prevalent and often co-exist in Bangladesh, a country in South Asia with one of the world's highest prevalences of preterm birth. To evaluate the individual and interactive effects of prenatal arsenic exposure, child marriage, and pregnancy weight gain on preterm birth in a prospective birth cohort in Bangladesh. During 2008-2011, we recruited 1613 pregnant women aged ≥18years at ≤16weeks of gestation and followed them until 1-month post-partum. We measured total arsenic in drinking water (n=1184) and in maternal toenails (n=1115) collected at enrollment and ≤1-month post-partum, respectively using inductively coupled plasma mass spectrometry. Child marriage (child marriage, and 0.64 (95% CI: 0.42-0.97) for a pound per week increase in maternal weight during the 2nd and 3rd trimesters. In stratified analysis by child marriage, pregnancy weight gain was inversely associated with preterm birth among women with a history of child marriage (RR=0.58; 95% CI: 0.37-0.92), but not among women with no history of child marriage (RR=86; 95% CI: 0.37-2.01). Mediation analysis revealed that both arsenic exposure and child marriage had small but significant associations with preterm birth via lowering pregnancy weight gain. Similar associations were observed when arsenic exposure was assessed using maternal toenail arsenic concentrations. Reducing arsenic exposure and ending child marriage could reduce the risk of preterm birth in Bangladesh. Furthermore, enhancing nutritional support to ensure adequate weight gain during pregnancy may provide additional benefits especially for women with a history of child marriage. Copyright © 2017 Elsevier Ltd. All rights

  15. 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.

  16. Arsenic residues in broiler meat and excreta at arsenic prone areas of Bangladesh

    Directory of Open Access Journals (Sweden)

    Amalendu Ghosh

    2012-08-01

    Full Text Available The aims of this study were to detect arsenic concentrations in feed, drinking water, tissues and excreta of broiler chickens in Bangladesh; and to assess the effect of arsenic in feed and drinking water on the retention of arsenic in broiler tissues and excreta. Total arsenic concentration (inorganic plus organic was determined by atomic absorption spectrophotometer. Mean (± SE levels of arsenic in drinking water, feed (dry weight and excreta (dry weight were 80.4 ± 5.5 µg/L, 119.0 ± 4.7 µg/kg and 1221.8 ± 58.3 µg/kg, respectively. In tissues (wet weight, highest arsenic concentration (µg/kg was in skin (218.8 ± 11.7, followed by liver (102.1 ± 8.0, lung (96.3 ± 5.6, kidney (88.2 ± 7.5 and thigh muscle (67.8 ± 5.1. Arsenic in broiler meat was below the maximum tolerable limits for humans. Accumulations of arsenic in tissues and excreta were boosted with the relative increment of arsenic in drinking water and feed. High arsenic in excreta could be an environmental issue in Bangladesh.

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

    Directory of Open Access Journals (Sweden)

    Hui Shen

    2016-02-01

    Full Text Available 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 (p< 0.000001 following arsenic exposure: inorganic arsenic (iAs, 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.

  18. Distinct arsenic metabolites following seaweed consumption in humans

    OpenAIRE

    Taylor, Vivien F.; Li, Zhigang; Sayarath, Vicki; Palys, Thomas J.; Morse, Kevin R.; Scholz-Bright, Rachel A.; Margaret R Karagas

    2017-01-01

    Seaweeds contain arsenic primarily in the form of arsenosugars, which can be metabolized to a wide range of arsenic compounds. To characterize human exposure to arsenic from seaweed consumption, we determined concentrations of arsenic species in locally available seaweeds, and assessed urinary arsenic compounds in an experimental feeding study. A total of 11 volunteers consumed 10?g per day of three types of seaweeds (nori, kombu, and wakame) for three days each, while abstaining from rice an...

  19. A broad view of arsenic.

    Science.gov (United States)

    Jones, F T

    2007-01-01

    In the mind of the general public, the words "arsenic" and "poison" have become almost synonymous. Yet, As is a natural metallic element found in low concentrations in virtually every part of the environment, including foods. Mining and smelting activities are closely associated with As, and the largest occurrence of As contamination in the United States is near the gold mines of northern Nevada. Inhabitants of Bangladesh and surrounding areas have been exposed to water that is naturally and heavily contaminated with As, causing what the World Health Organization has described as the worst mass poisoning in history. Although readily absorbed by humans, most inorganic As (>90%) is rapidly cleared from the blood with a half-life of 1 to 2 h, and 40 to 70% of the As intake is absorbed, metabolized, and excreted within 48 h. Arsenic does not appreciably bioaccumulate, nor does it biomagnify in the food chain. The United States has for some time purchased more As than any other country in the world, but As usage is waning, and further reductions appear likely. Arsenic is used in a wide variety of industrial applications, from computers to fireworks. All feed additives used in US poultry feeds must meet the strict requirements of the US Food and Drug Administration Center for Veterinary Medicine (Rockville, MD) before use. Although some public health investigators have identified poultry products as a potentially significant source of total As exposure for Americans, studies consistently demonstrate that <1% of samples tested are above the 0.5 ppm limit established by the US Food and Drug Administration Center for Veterinary Medicine. Although laboratory studies have demonstrated the possibility that As in poultry litter could pollute ground waters, million of tons of litter have been applied to the land, and no link has been established between litter application and As contamination of ground water. Yet, the fact that <2% of the United States population is involved in

  20. 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.

  1. Arsenic Sorption on Mechanically Activated Magnetite and Olivine

    Directory of Open Access Journals (Sweden)

    Zdenka Bujňáková

    2012-12-01

    Full Text Available Arsenic sorption on mechanically activated minerals such as magnetite Fe3O4 (Kiruna, Sweden and olivine (Mg,Fe2SiO4 (Ǻheim,Norway has been studied and compared in this work. Experiments were carried out with non-activated and mechanically activatedsamples. The activation of both minerals was performed in a planetary mill at different milling conditions. The specific surface areaand consequent sorption activity were enhanced by mechanical activation. The using of olivine seems to be better than magnetite fromthe point of view of milling time, which is necessary for achievement of the same sorption effect.

  2. Vascular permeability alterations induced by arsenic.

    Science.gov (United States)

    Chen, Shih-Chieh; Tsai, Ming-Hsien; Wang, Hsiu-Jen; Yu, Hsin-Su; Chang, Louis W

    2004-01-01

    The impact of arsenic on the integrity of blood vessels in vivo via in situ exposure (local injection) of arsenic was investigated. Vascular permeability changes were evaluated by means of the Evans blue assay and the India ink tracer techniques. Rats were intravenously injected with Evans blue followed by intradermal injections of various doses of sodium arsenite on the back skins of the animals. Evans blue at different time points was extracted and assayed as indices of vascular leakage. Skin at various time point injection sites was sampled for arsenic measurement via graphite furnace atomic absorption spectroscopy. Our time course study with Evans blue technique demonstrated a biphasic pattern of vascular permeability change: an early phase of permeability reduction and a later phase of permeability promotion at all dose levels tested. The India ink tracer technique also demonstrated a time-correlated increase in vascular labelling in the tissues examined, signifying an increase in vascular leakage with time. Moreover, we found that despite an early increase in tissue arsenic content at time of injection, tissue arsenic declined rapidly and returned to near control levels after 30-60 min. Thus, an inverse correlation between tissue arsenic content and the extent of vascular permeability was apparent. This study provides the first demonstration that in situ exposure to arsenic will produce vascular dysfunction (vascular leakage) in vivo.

  3. A literature study on Arsenic Compounds

    Directory of Open Access Journals (Sweden)

    Cho, Tae-Sung

    2002-02-01

    Full Text Available Objective: The purpose of this study is to develop and activate the methods of using the arsenic compounds as the anti-cancer medicine. Methods: We investigated some literatures on the using methods, the effects for anti-cancer, and the toxicity of the arsenic compounds. Results: The results are summarized as follows. 1. As is the one of the nitrogen familIy(5A familly. 2. The Arsenic compounds which have been used as the one of the oriental medicine are the Arsenicum Sulbimatum(A52O3 and the Realgar(AsS. 3. As+ 3 is more toxic than the other arsenic compounds. The fatal amount is 100-300 mg. So, it is used 1-5 mg/day as a medicine. 4. The Arsenicwn Sulbimatum(A52O3 and the Realgar(AsS are used after the heat treatment or the boiling with the acetic acid. 5. The gastrointestinal tract, vessel, and respiration are affected by the acute toxicity of the arsenic compounds. 6. The arsenic compounds are good for the dermatosis and the malignant cancer, especially the acute promyelocytic leukcrnia(APL. we should study the reason of these and the different effect in concentration, also develop new methods of using the the arsenic compounds as getting rid of their toxicity.

  4. Subsurface iron and arsenic removal for drinking water treatment in Bangladesh

    NARCIS (Netherlands)

    Van Halem, D.

    2011-01-01

    Arsenic contamination of shallow tube well drinking water is an urgent health problem in Bangladesh. Current arsenic mitigation solutions, including (household) arsenic removal options, do not always provide a sustainable alternative for safe drinking water. A novel technology, Subsurface Arsenic

  5. ARSENIC SPECIATION IN CARROT EXTRACTS WITH AN EMPHASIS ON THE DETECTION OF MMA(III) AND MMTA

    Science.gov (United States)

    The two predominant routes of arsenic exposure are dietary ingestion and drinking water consumption. Dietary arsenic, unlike drinking water arsenic, contains a variety of arsenicals with dramatically different toxicities. The list of arsenicals detected in dietary samples conti...

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

    OpenAIRE

    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), meth...

  7. 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.

  8. Technology for remediation and disposal of arsenic.

    Science.gov (United States)

    Visoottiviseth, Pornsawan; Ahmed, Feroze

    2008-01-01

    Groundwater contaminated with arsenic must be treated to meet stringent drinking water standards or guideline values. In recent years, several reliable, cost-effective, and sustainable treatment technologies have been developed, although improvements will continue to emerge as work continues. All treatment technologies work by concentrating arsenic at some stage of treatment. Large-scale use of arsenic removal systems generates arsenic-rich treatment wastes, and indiscriminate disposal of these sizable wastes may lead to environmental pollution. Safe disposal of arsenic-rich media is a growing environmental concern that needs to be addressed. For the developing world, arsenic-contaminated water requires some form of treatment to be sufficiently safe for consumption by local populations. Such treatment is particularly important where arsenic [particularly as As(III)] levels in raw water exceed 200 microg/L. At this level and above, >95% removal efficiency is required to produce water that meets international standards, an unlikely result in many locations. Alternative sources for securing safe water may also include rainwater harvesting, use of uncontaminated (filtered) surface waters, and water extraction from new deep tube wells and dug wells. There are disadvantages attendant to using these alternative water sources. For example, rainwater has few mineral salts and is subject to contamination from air pollution or by microbes, including pathogens. Similarly, surface waters, e.g., pond waters, or water from dug wells may require purification before use. Excessive pumping from deep tube wells may lower the water table sufficiently to allow entry of arsenic-contaminated waters from shallower horizons. Bioremediation and phytoremediation are more suitable to developing countries where sunlight is plentiful. In such countries, plant biodiversity is also great and may allow identification of plants suitable for bioremediation. In addition to removing arsenic from water

  9. Role of soil-derived dissolved substances in arsenic transport and transformation in laboratory experiments.

    Science.gov (United States)

    Chen, Zhangrong; Cai, Yong; Liu, Guangliang; Solo-Gabriele, Helena; Snyder, George H; Cisar, John L

    2008-11-15

    Dissolved substances derived from soil may interact with both soil surfaces and with arsenic and subsequently influence arsenic mobility and species transformation. The purpose of this study was to investigate arsenic transport and transformation in porous media with a specific focus on the impact of soil-derived dissolved substances, mainly consisting of inorganic colloids and dissolved organic matter (DOM), on these processes. Arsenic transport and transformation through columns, which were packed with uncoated sand (UC) or naturally coated sand (NC) and fed with arsenate (AsV) or monomethylarsonic acid (MMA) spiked influents, were investigated in the presence or absence of soil-derived dissolved substances. The presence of soil-derived inorganic colloids and/or DOM clearly enhanced As transport through the column, with the fraction of As leached out of column (referring to the total amount added) being increased from 23 to 46% (UC) and 21 to 50% (NC) in AsV experiments while 46 to 64% (UC) and 28 to 63% (NC) in MMA experiments. The association of arsenic with DOM and the competitive adsorption between arsenic and DOM could account for, at least partly, the enhanced As movement. Distinct species transformation of As during transport through soil columns was observed. When AsV was the initial species spiked in the influent solutions, only arsenite (AsIII) was detected in the effluents for UC columns; while both AsIII (dominant) and AsV were present for NC columns, with AsIII being the dominant species. When MMA was initially spiked in the influent solutions, all method detectable As species, AsIII, AsV, MMA, and dimethylarsenic acid (DMA) were present in the effluents for both soil columns. These results indicate that risk assessment associated with As contamination, particularly due to previous organoarsenical pesticide applications, should take into account the role of soil-derived dissolved substances in promoting As transport and As species transformation.

  10. 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

  11. Electrochemical arsenic remediation for rural Bangladesh

    Science.gov (United States)

    Addy, Susan Elizabeth Amrose

    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 mug/L arsenic (including both As[III] and As[V] in a 1:1 ratio) to below the WHO recommended maximum limit of 10 mug/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 mum 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--500 mug/L) in real Bangladesh tube well water collected

  12. Urinary arsenic levels in timber treatment operators.

    Science.gov (United States)

    Gollop, B R; Glass, W I

    1979-01-10

    An investigation was carried out into arsenic levels in urine of timber treatment operators at six treatment plants in the Waikato-Rotorua area. The mean arsenic level for treatment operators was 222 migrograms/l compared with the normal range of 5-40 micrograms/l. In order to reduce the present significant exposure to treatment chemicals such as arsenic and chromium, it is recommended that the wood preservation industry take engineering measures to reduce the present air emissions and adopt strict work practices in hygiene and protective clothing in similar manner to those handling mercury and lead.

  13. Health implications of arsenic in drinking water

    Energy Technology Data Exchange (ETDEWEB)

    Pontius, F.W. (American Water Works Association, Denver, CO (United States)); Brown, K.G. (Kenneth G. Brown Inc., Chapel Hill, NC (United States)); Chen, C.J. (National Taiwan Univ., Taipei (Taiwan, Province of China). Inst. of Public Health)

    1994-09-01

    The adequacy of the current maximum contaminant level (MCL) for arsenic is being evaluated by the US Environmental Protection Agency. If recent theoretical estimates of chronic effects and cancer risks prove accurate, the current MCL may not effectively protect health. Knowledge of arsenic pharmacokinetics and mechanisms in humans, however, is not complete enough to provide a definitive answer, and current epidemiologic evidence is too inconsistent and too fraught with uncertainty regarding arsenic exposure to be helpful in assessing low-level risks. 85 refs.

  14. Insights into arsenic multi-operons expression and arsenic resistance mechanisms in Rhodopseudomonas palustris CGA009

    Directory of Open Access Journals (Sweden)

    Chungui eZhao

    2015-09-01

    Full Text Available Arsenic (As is widespread in the environment and causes numerous health problems. Rhodopseudomonas palustris has been regarded as a good model organism for studying arsenic detoxification since it was first demonstrated to methylate environmental arsenic by conversion to soluble or gaseous methylated species. However, the detailed arsenic resistance mechanisms remain unknown though there are at least three arsenic-resistance operons (ars1, ars2 and ars3 in R. palustris. In this study, we investigated how arsenic multi-operons contributed to arsenic detoxification in R. palustris. The expression of ars2 or ars3 operons increased with increasing environmental arsenite (As(III concentrations (up to 1.0 mM while transcript of ars1 operon was not detected in the middle log-phase (55 h. ars2 operon was actively expressed even at the low concentration of As(III (0.01 μM, whereas the ars3 operon was expressed at 1.0 µM of As(III, indicating that there was a differential regulation mechanism for the three arsenic operons. Furthermore, ars2 and ars3 operons were maximally transcribed in the early log-phase where ars2 operon was 5.4-fold higher than that of ars3 operon. A low level of ars1 transcript was only detected at 43 h (early log-phase. Arsenic speciation analysis demonstrated that R. palustris could reduce As(V to As(III.

  15. Current Status and Prevention Strategy for Coal-arsenic Poisoning in Guizhou, China

    OpenAIRE

    Li, Dasheng; An, Dong; Zhou, Yunsu; Liu, Jie; Waalkes, Michael P.

    2006-01-01

    Arsenic exposure from burning coal with high arsenic contents occurs in southwest Guizhou, China. Coal in this region contains extremely high concentrations of inorganic arsenic. Arsenic exposure from coal-burning is much higher than exposure from arsenic-contaminated water in other areas of China. The current status and prevention strategies for arsenic poisoning from burning high-arsenic coal in southwest Guizhou, China, is reported here. Over 3,000 arsenic-intoxicated patients were diagnos...

  16. 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

  17. Arsenic contamination of groundwater: Mitigation strategies and policies

    Science.gov (United States)

    Alaerts, Guy J.; Khouri, Nadim

    Contamination of groundwater by arsenic from natural geochemical sources is at present a most serious challenge in the planning of large-scale use of groundwater for drinking and other purposes. Recent improvements in detection limits of analytical instruments are allowing the correlation of health impacts such as cancer with large concentrations of arsenic in groundwater. However, there are at present no known large-scale technological solutions for the millions of people-mostly rural-who are potentially affected in developing countries. An overall framework of combating natural resource degradation is combined with case studies from Chile, Mexico, Bangladesh and elsewhere to arrive at a set of strategic recommendations for the global, national and local dimensions of the arsenic ``crisis''. The main recommendations include: the need for flexibility in the elaboration of any arsenic mitigation strategy, the improvement and large-scale use of low-cost and participatory groundwater quality testing techniques, the need to maintain consistent use of key lessons learned worldwide in water supply and sanitation and to integrate arsenic as just one other factor in providing a sustainable water supply, and the following of distinct but communicable tracks between arsenic-related developments and enhanced, long-term, sustainable water supplies. La contamination des eaux souterraines par l'arsenic provenant de sources naturelles est actuellement un sujet des plus graves dans l'organisation d'un recours à grande échelle des eaux souterraines pour la boisson et d'autres usages. De récentes améliorations dans les limites de détection des équipements analytiques permettent de corréler les effets sur la santé tels que le cancer à de fortes concentrations en arsenic dans les eaux souterraines. Toutefois, il n'existe pas actuellement de solutions technologiques à grande échelle connues pour des millions de personnes, surtout en zones rurales, qui sont potentiellement

  18. Iron-impregnated granular activated carbon for arsenic removal from drinking water

    Science.gov (United States)

    Chang, Qigang

    conducted to investigate the performance of Fe-GACs in real implementations using groundwater taken from a former superfund site in North Dakota. Fe-GACs can remove arsenic below 10 microg/L and the performance of Fe-GACs was significantly enhanced with increasing empty bed contact time.

  19. Mineral arsenicals in traditional medicines: orpiment, realgar, and arsenolite.

    Science.gov (United States)

    Liu, Jie; Lu, Yuanfu; Wu, Qin; Goyer, Robert A; Waalkes, Michael P

    2008-08-01

    Mineral arsenicals have long been used in traditional medicines for various diseases, yet arsenic can be highly toxic and carcinogenic. Arsenic in traditional medicines typically comes from deliberate addition for therapeutic purposes, mainly in the form of mineral arsenicals, including orpiment (As2S3), realgar (As4S4), and arsenolite (contains arsenic trioxide, As2O3). Inorganic arsenic is now accepted in Western medicine as a first line chemotherapeutic agent against certain hematopoietic cancers. This perspective analyzes the pharmacology and toxicology of these arsenicals used in traditional medicines. Orpiment and realgar are less soluble and poorly absorbed from the gastrointestinal tract, whereas the bioavailability of arsenic trioxide is similar to inorganic arsenic salts such as sodium arsenite. Pharmacological studies show that arsenic trioxide and realgar are effective against certain malignancies. Orpiment and realgar are used externally for various skin diseases. Realgar is frequently included as an ingredient in oral traditional remedies for its antipyretic, anti-inflammatory, antiulcer, anti-convulsive, and anti-schistosomiasis actions, but the pharmacological basis for this inclusion still remains to be fully justified. Toxicological studies show that cardiovascular toxicity is the major concern for arsenic trioxide and that the gastrointestinal and dermal adverse effects may occur after prolonged use of mineral arsenicals. Little is known regarding the possible secondary cancers resulting from the long-term use of any of these arsenicals. Similar to the safety evaluation of seafood arsenicals, total arsenic content alone appears to be insufficient for mineral arsenical safety evaluation. Arsenic speciation, bioavailability, and toxicity/benefit should be considered in evaluation of mineral arsenical-containing traditional medicines.

  20. 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

  1. Arsenic stress after the Proterozoic glaciations.

    Science.gov (United States)

    Fru, Ernest Chi; Arvestål, Emma; Callac, Nolwenn; El Albani, Abderrazak; Kilias, Stephanos; Argyraki, Ariadne; Jakobsson, Martin

    2015-12-04

    Protection against arsenic damage in organisms positioned deep in the tree of life points to early evolutionary sensitization. Here, marine sedimentary records reveal a Proterozoic arsenic concentration patterned to glacial-interglacial ages. The low glacial and high interglacial sedimentary arsenic concentrations, suggest deteriorating habitable marine conditions may have coincided with atmospheric oxygen decline after ~2.1 billion years ago. A similar intensification of near continental margin sedimentary arsenic levels after the Cryogenian glaciations is also associated with amplified continental weathering. However, interpreted atmospheric oxygen increase at this time, suggests that the marine biosphere had widely adapted to the reorganization of global marine elemental cycles by glaciations. Such a glacially induced biogeochemical bridge would have produced physiologically robust communities that enabled increased oxygenation of the ocean-atmosphere system and the radiation of the complex Ediacaran-Cambrian life.

  2. 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

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

    Science.gov (United States)

    Stanton, Bruce A; Caldwell, Kathleen; Congdon, Clare Bates; Disney, Jane; Donahue, Maria; Ferguson, Elizabeth; Flemings, Elsie; Golden, Meredith; Guerinot, Mary Lou; Highman, Jay; James, Karen; Kim, Carol; Lantz, R Clark; Marvinney, Robert G; Mayer, Greg; Miller, David; Navas-Acien, Ana; Nordstrom, D Kirk; Postema, Sonia; Rardin, Laurie; Rosen, Barry; SenGupta, Arup; Shaw, Joseph; Stanton, Elizabeth; Susca, Paul

    2015-09-01

    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 international standards. Although the US Environmental Protection Agency (EPA) has set a limit of 10 μg/L in public water supplies and the WHO has recommended an upper limit of 10 μg/L, recent studies indicate that these limits are not protective enough. In addition, there are currently few standards for arsenic in food. Those who participated in the Summit support citizens, scientists, policymakers, industry, and educators at the local, state, national, and international levels to (1) establish science-based evidence for setting standards at the local, state, national, and global levels for arsenic in water and food; (2) work with government agencies to set regulations for arsenic in water and food, to establish and strengthen non-regulatory programs, and to strengthen collaboration among government agencies, NGOs, academia, the private sector, industry, and others; (3) develop novel and cost-effective technologies for identification and reduction of exposure to arsenic in water; (4) develop novel and cost-effective approaches to reduce arsenic exposure in juice, rice, and other relevant foods; and (5) develop an Arsenic Education Plan to guide the development of science curricula as well as community outreach and education programs that serve to inform students and consumers about arsenic exposure and engage them in well water testing and development of remediation strategies.

  4. Arsenic Exposure From Drinking Water, Arsenic Methylation Capacity, and Carotid Intima-Media Thickness in Bangladesh

    Science.gov (United States)

    Chen, Yu; Wu, Fen; Graziano, Joseph H.; Parvez, Faruque; Liu, Mengling; Paul, Rina Rani; Shaheen, Ishrat; Sarwar, Golam; Ahmed, Alauddin; Islam, Tariqul; Slavkovich, Vesna; Rundek, Tatjana; Demmer, Ryan T.; Desvarieux, Moise; Ahsan, Habibul

    2013-01-01

    We conducted a cross-sectional study to evaluate the interrelationships between past arsenic exposure, biomarkers specific for susceptibility to arsenic exposure, and carotid intima-media thickness (cIMT) in 959 subjects from the Health Effects of Arsenic Longitudinal Study in Bangladesh. We measured cIMT levels on average 7.2 years after baseline during 2010–2011. Arsenic exposure was measured in well water at baseline and in urine samples collected at baseline and during follow-up. Every 1-standard-deviation increase in urinary arsenic (357.9 µg/g creatinine) and well-water arsenic (102.0 µg/L) concentration was related to a 11.7-µm (95% confidence interval (CI): 1.8, 21.6) and 5.1-µm (95% CI: −0.2, 10.3) increase in cIMT, respectively. For every 10% increase in monomethylarsonic acid (MMA) percentage, there was an increase of 12.1 µm (95% CI: 0.4, 23.8) in cIMT. Among participants with a higher urinary MMA percentage, a higher ratio of urinary MMA to inorganic arsenic, and a lower ratio of dimethylarsinic acid to MMA, the association between well-water arsenic and cIMT was stronger. The findings indicate an effect of past long-term arsenic exposure on cIMT, which may be potentiated by suboptimal or incomplete arsenic methylation capacity. Future prospective studies are needed to confirm the association between arsenic methylation capacity and atherosclerosis-related outcomes. PMID:23788675

  5. Arsenic and its compounds in mushrooms: A review.

    Science.gov (United States)

    Falandysz, Jerzy; Rizal, Leela M

    2016-10-01

    The purpose of this article is to review the detail concentration of arsenic in some species of mushrooms as well as organic and inorganic forms of arsenic in the substrates where wild and cultivated edible mushrooms grow. We also briefly review the molecular forms of arsenic in mushrooms. There is still a lack of experimental data from the environment for a variety of species from different habitats and for different levels of geogenic arsenic in soil. This information will be useful for mushrooms consumers, nutritionists, and food regulatory agencies by describing ways to minimize arsenic content in edible mushrooms and arsenic intake from mushroom meals.

  6. Treatment of arsenic in acid wastewater and river sediment by Fe@Fe2O3 nanobunches: The effect of environmental conditions and reaction mechanism.

    Science.gov (United States)

    Tang, Lin; Feng, Haopeng; Tang, Jing; Zeng, Guangming; Deng, Yaocheng; Wang, Jiajia; Liu, Yani; Zhou, Yaoyu

    2017-06-15

    High concentration of arsenic in acid wastewater and polluted river sediment caused by metallurgical industry has presented a great environmental challenge for decades. Nanoscale zero valent iron (nZVI) can detoxify arsenic-bearing wastewater and groundwater, but the low adsorption capacity and rapid passivation restrict its large-scale application. This study proposed a highly efficient arsenic treatment nanotechnology, using the core-shell Fe@Fe2O3 nanobunches (NBZI) for removal of arsenic in acid wastewater with cyclic stability and transformation of arsenic speciation in sediment. The adsorption capacity of As(III) by NBZI was 60 times as high as that of nanoscale zero valent iron (nZVI) at neutral pH. Characterization of the prepared materials after reaction revealed that the contents of As(III) and As(V) were 65% and 35% under aerobic conditions, respectively, which is the evidence of oxidation included in the reaction process apart from adsorption and co-precipitation. The presence of oxygen was proved to improve the adsorption ability of the prepared NBZI towards As(III) with the removal efficiency increasing from 68% to 92%. In order to further enhance the performance of NBZI-2 in the absence of oxygen, a new Fenton-Like system of NBZI/H2O2 to remove arsenic under the anoxic condition was also proposed. Furthermore, the removal efficiency of arsenic in acid wastewater remained to be 78% after 9 times of cycling. Meanwhile, most of the mobile fraction of arsenic in river sediment was transformed into residues after NBZI treatment for 20 days. The reaction mechanism between NBZI and arsenic was discussed in detail at last, indicating great potential of NBZI for the treatment of arsenic in wastewater and sediment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Arsenic-Induced Antioxidant Depletion, Oxidative DNA Breakage, and Tissue Damages are Prevented by the Combined Action of Folate and Vitamin B12.

    Science.gov (United States)

    Acharyya, Nirmallya; Deb, Bimal; Chattopadhyay, Sandip; Maiti, Smarajit

    2015-11-01

    Arsenic is a grade I human carcinogen. It acts by disrupting one-carbon (1C) metabolism and cellular methyl (-CH3) pool. The -CH3 group helps in arsenic disposition and detoxification of the biological systems. Vitamin B12 and folate, the key promoters of 1C metabolism were tested recently (daily 0.07 and 4.0 μg, respectively/100 g b.w. of rat for 28 days) to evaluate their combined efficacy in the protection from mutagenic DNA-breakage and tissue damages. The selected tissues like intestine (first-pass site), liver (major xenobiotic metabolizer) and lung (major arsenic accumulator) were collected from arsenic-ingested (0.6 ppm/same schedule) female rats. The hemo-toxicity and liver and kidney functions were monitored. Our earlier studies on arsenic-exposed humans can correlate carcinogenesis with DNA damage. Here, we demonstrate that the supplementation of physiological/therapeutic dose of vitamin B12 and folate protected the rodents significantly from arsenic-induced DNA damage (DNA fragmentation and comet assay) and hepatic and renal tissue degeneration (histo-architecture, HE staining). The level of arsenic-induced free-radical products (TBARS and conjugated diene) was significantly declined by the restored actions of several antioxidants viz. urate, thiol, catalase, xanthine oxidase, lactoperoxidase, and superoxide dismutase in the tissues of vitamin-supplemented group. The alkaline phosphatase, transaminases, urea and creatinine (hepatic and kidney toxicity marker), and lactate dehydrogenase (tissue degeneration marker) were significantly impaired in the arsenic-fed group. But a significant protection was evident in the vitamin-supplemented group. In conclusion, the combined action of folate and B12 results in the restitution in the 1C metabolic pathway and cellular methyl pool. The cumulative outcome from the enhanced arsenic methylation and antioxidative capacity was protective against arsenic induced mutagenic DNA breakages and tissue damages.

  8. Arsenic and Growth of Amphistegina gibbosa

    Directory of Open Access Journals (Sweden)

    Elise Keister

    2009-01-01

    Full Text Available A laboratory tested various concentrations of arsenic on the growth of foraminifera and recorded their findings. Upon examination, the plotted probability density function for each of these trials resembled a similar shape. The plots were then characterized in a general model composed of linear segments. Using calculus, statistics such as the expected value, variance and standard deviation were calculated to interpret the collected data. The statistics revealed that arsenic limits the growth of ocean life.

  9. Biosensors for Inorganic and Organic Arsenicals

    OpenAIRE

    Chen, Jian; Rosen, Barry P.

    2014-01-01

    Arsenic is a natural environmental contaminant to which humans are routinely exposed and is strongly associated with human health problems, including cancer, cardiovascular and neurological diseases. To date, a number of biosensors for the detection of arsenic involving the coupling of biological engineering and electrochemical techniques has been developed. The properties of whole-cell bacterial or cell-free biosensors are summarized in the present review with emphasis on their sensitivity a...

  10. 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.

  11. 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.

  12. 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.

  13. Thermal effects on arsenic emissions during coal combustion process.

    Science.gov (United States)

    Zhang, Weiqiang; Sun, Qiang; Yang, Xiuyuan

    2018-01-15

    In this study, the rate of emission of arsenic during the burning process of different kinds of coal is examined in order to study the volatile characteristics of arsenic during coal combustion which have negative effects on the ecological environment and human health. The results show that the emission rate of arsenic gradually increases with increased burning temperature, with a threshold of approximately 700°C to 800°C in the process of temperature increase. Then, the relationships among the arsenic emission rate and combustion environment, original arsenic content, combustion time, burning temperature, air flow and amount of arsenic fixing agent are discussed, and it is found that except for the original arsenic content, the rest of the factors have a nonlinear relationship with the emission rate of arsenic. That is, up to a certain level, they all contribute to the release of arsenic, and then their impact is minimal. The original arsenic content in coal is proportional to the arsenic emission rate. Therefore, taking into consideration the nonlinear relationships between factors that affect the arsenic emission rate can reduce contamination from arsenic. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. 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.

  15. 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 ...

  16. 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.

  17. RECENT ADVANCES IN ARSENIC CARCINOGENESIS: MODES OF ACTION, ANIMAL MODEL SYSTEMS AND METHYLATED ARSENIC METABOLITES

    Science.gov (United States)

    Abstract: Recent advances in our knowledge of arsenic carcinogenesis include the development of rat or mouse models for all human organs in which inorganic arsenic is known to cause cancer -skin, lung, urinary bladder, liver and kidney. Tumors can be produced from eit...

  18. 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

  19. Levels of arsenic in human hair as biomarkers of arsenic exposure ...

    African Journals Online (AJOL)

    Arsenic levels were determined in human hair samples collected from a mining and non-mining community in Ghana. Hair samples were digested and analyzed using inductively coupled plasma atomic emission spectrometer (ICP–AES). Elevated levels of arsenic were found in the samples obtained from the mining ...

  20. Folate-mediated intracellular drug delivery increases the anticancer efficacy of nanoparticulate formulation of arsenic trioxide.

    Science.gov (United States)

    Chen, Haimei; Ahn, Richard; Van den Bossche, Jeroen; Thompson, David H; O'Halloran, Thomas V

    2009-07-01

    Arsenic trioxide (As(2)O(3)) is a frontline drug for treatment of acute promyelocytic leukemia and is in clinical trials for treatment of other malignancies, including multiple myeloma; however, efforts to expand clinical utility to solid tumors have been limited by toxicity. Nanoparticulate forms of As(2)O(3) encapsulated in 100-nm-scale, folate-targeted liposomes have been developed to lower systematic toxicity and provide a platform for targeting this agent. The resultant arsenic "nanobins" are stable under physiologic conditions but undergo triggered drug release when the pH is lowered to endosomal/lysosomal levels. Cellular uptake and antitumor efficacy of these arsenic liposomes have been evaluated in folate receptor (FR)-positive human nasopharyngeal (KB) and cervix (HeLa) cells, as well as FR-negative human breast (MCF-7) tumor cells through confocal microscopy, inductively coupled plasma mass spectroscopy, and cytotoxicity studies. Uptake of folate-targeted liposomal arsenic by KB cells was three to six times higher than that of free As(2)O(3) or nontargeted liposomal arsenic; the enhanced uptake occurs through folate-mediated endocytosis, leading to a 28-fold increase in cytotoxicity. In contrast, tumor cells with lower FR density on the surface (HeLa and MCF-7) showed much less uptake of the folate-targeted drug and lower efficacy. In cocultures of KB and MCF-7 cells, the folate-targeted arsenic liposomes were exclusively internalized by KB cells, showing high targeting specificity. Our studies further indicate that folate-targeted delivery of As(2)O(3) with coencapsulated nickel(II) ions (as a nontoxic adjuvant) potentiates the As(2)O(3) efficacy in relatively insensitive solid tumor-derived cells and holds the promise of improving drug therapeutic index.

  1. Arsenic trioxide and Ascorbic Acid Demonstrates Promising Activity against Primary Human CLL Cells in Vitro

    Science.gov (United States)

    Biswas, Sabyasachi; Zhao, Xiaobin B.; Mone, Andrew P; Mo, Xiaokui; Vargo, Melissa; Jarjoura, David; Byrd, John C; Muthusamy, Natarajan

    2014-01-01

    The compromised antioxidant defense system in chronic lymphocytic leukemia (CLL) suggested a potential use for Reactive Oxygen Species (ROS) generating Arsenic Trioxide (ATO) and Ascorbic Acid. While both ATO and ascorbic acid mediated cytotoxicity in CLL B cells as single agents, the efficacy of ATO is enhanced by ascorbic acid. This effect is dependent on increased ROS accumulation, as pretreatment of B-CLL cells with a glutathione reducing buthionine sulfoximine or catalase inhibiting aminotriazole, enhanced ATO/ascorbic acid mediated cytotoxicity. Petreatment with reducing agents such as catalase, or thiol anti-oxidant, N-acetyl cysteine or GSH also abrogated ATO/ascorbic acid mediated cytotoxicity. Furthermore, Hu1D10 mediated cell death was enhanced with ATO and ascorbic acid, thus justifying potential combination of ATO/arsenic trioxide therapy with antibodies such as Hu1D10 that also cause accumulation of ROS. PMID:20171736

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

    Science.gov (United States)

    Faita, Francesca; Cori, Liliana; Bianchi, Fabrizio; Andreassi, Maria Grazia

    2013-01-01

    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. PMID:23583964

  3. Enhanced

    Directory of Open Access Journals (Sweden)

    Martin I. Bayala

    2014-06-01

    Full Text Available Land Surface Temperature (LST is a key parameter in the energy balance model. However, the spatial resolution of the retrieved LST from sensors with high temporal resolution is not accurate enough to be used in local-scale studies. To explore the LST–Normalised Difference Vegetation Index relationship potential and obtain thermal images with high spatial resolution, six enhanced image sharpening techniques were assessed: the disaggregation procedure for radiometric surface temperatures (TsHARP, the Dry Edge Quadratic Function, the Difference of Edges (Ts∗DL and three models supported by the relationship of surface temperature and water stress of vegetation (Normalised Difference Water Index, Normalised Difference Infrared Index and Soil wetness index. Energy Balance Station data and in situ measurements were used to validate the enhanced LST images over a mixed agricultural landscape in the sub-humid Pampean Region of Argentina (PRA, during 2006–2010. Landsat Thematic Mapper (TM and Moderate Resolution Imaging Spectroradiometer (EOS-MODIS thermal datasets were assessed for different spatial resolutions (e.g., 960, 720 and 240 m and the performances were compared with global and local TsHARP procedures. Results suggest that the Ts∗DL technique is the most adequate for simulating LST to high spatial resolution over the heterogeneous landscape of a sub-humid region, showing an average root mean square error of less than 1 K.

  4. High levels of inorganic arsenic in rice in areas where arsenic-contaminated water is used for irrigation and cooking.

    Science.gov (United States)

    Rahman, M Azizur; Hasegawa, H

    2011-10-15

    Rice is the staple food for the people of arsenic endemic South (S) and South-East (SE) Asian countries. In this region, arsenic contaminated groundwater has been used not only for drinking and cooking purposes but also for rice cultivation during dry season. Irrigation of arsenic-contaminated groundwater for rice cultivation has resulted high deposition of arsenic in topsoil and uptake in rice grain posing a serious threat to the sustainable agriculture in this region. In addition, cooking rice with arsenic-contaminated water also increases arsenic burden in cooked rice. Inorganic arsenic is the main species of S and SE Asian rice (80 to 91% of the total arsenic), and the concentration of this toxic species is increased in cooked rice from inorganic arsenic-rich cooking water. The people of Bangladesh and West Bengal (India), the arsenic hot spots in the world, eat an average of 450g rice a day. Therefore, in addition to drinking water, dietary intake of arsenic from rice is supposed to be another potential source of exposure, and to be a new disaster for the population of S and SE Asian countries. Arsenic speciation in raw and cooked rice, its bioavailability and the possible health hazard of inorganic arsenic in rice for the population of S and SE Asia have been discussed in this review. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. 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.

  6. Arsenic

    Science.gov (United States)

    ... Luginaah I, Clarke E, Marfoh K, et al. Environ Health Perspect. 2015;123(5):412-21. (2) ... Data Media centre Publications Countries Programmes and projects Governance About WHO Help and Services Contacts FAQs Employment ...

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

    Science.gov (United States)

    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 international standards. Although the U.S. Environmental Protection Agency (EPA) has set a limit of 10 micrograms per liter (10 μg/L) in public water supplies and the WHO has recommended an upper limit of 10 μg/L, recent studies indicate that these limits are not protective enough. In addition, there are currently few standards for arsenic in food. Those who participated in the Summit support citizens, scientists, policymakers, industry and educators at the local, state, national and international levels to: (1) Establish science-based evidence for setting standards at the local, state, national, and global levels for arsenic in water and food; (2) Work with government agencies to set regulations for arsenic in water and food, to establish and strengthen non-regulatory programs, and to strengthen collaboration among government agencies, NGOs, academia, the private sector, industry and others; (3) Develop novel and cost-effective technologies for identification and reduction of exposure to arsenic in water; (4) Develop novel and cost-effective approaches to reduce arsenic exposure in juice, rice, and other relevant foods, and (5) Develop an Arsenic Education Plan to guide the development of science curricula as well as community outreach and education programs that serve to inform students and consumers about arsenic exposure and engage them in well water testing and development of remediation strategies. PMID:26231509

  8. Clinical manifestations and arsenic methylation after a rare subacute arsenic poisoning accident.

    Science.gov (United States)

    Xu, Yuanyuan; Wang, Yi; Zheng, Quanmei; Li, Bing; Li, Xin; Jin, Yaping; Lv, Xiuqiang; Qu, Guang; Sun, Guifan

    2008-06-01

    One hundred and four workers ingested excessive levels of arsenic in an accident caused by leakage of pipeline in a copper-smelting factory. Clinical examinations were performed by physicians in a local hospital. Excreted urinary arsenic species were determined by cold trap hydride generation atomic absorption spectrometry. In the initial toxic phase, gastrointestinal symptoms were predominant (83 people, 79.8%). Most patients showed leucopenia (72 people, 69.2%), and increased serum alanine aminotransferase (84 people, 80.8%) and aspartate aminotransferase (58 people, 55.8%). Thirty-five patients (33.6%) had elevated red blood cells in urine. After 17 days of admission, many subjects (45 people, 43.3%) developed peripheral neuropathy and 25 of these 45 patients (24.0%) showed a decrease in motor and sensory nerve conduction velocity. In the comparison of urinary arsenic metabolites among subacute arsenic-poisoned, chronic high arsenic-exposed and control subjects, we found that subacute arsenic-poisoned patients had significantly elevated proportions of urinary inorganic arsenic (iAs) and methylarsonic acid (MMA) but reduced proportion of urinary dimethylarsinic acid (DMA) compared with chronic high arsenic-exposed and control subjects. Chronic exposed subjects excreted higher proportions of iAs and MMA but lower proportions of DMA in urine compared with control subjects. These results suggest that gastrointestinal symptoms, leucopenia, and hepatic and urinary injury are predominant in the initial phase of subacute arsenic poisoning. Peripheral neuropathy is the most frequent manifestation after the initial phase. The biomethylation of arsenic decreases in a dose rate-dependent manner.

  9. Map of Arsenic concentrations in groundwater of the United States

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The map graphic image at http://water.usgs.gov/GIS/browse/arsenic_map.png illustrates arsenic values, in micrograms per liter, for groundwater samples from about...

  10. Development of a Simple System for the Determination of Arsenic ...

    African Journals Online (AJOL)

    Bioline

    Development of a Simple System for the Determination of Arsenic after Hydride. Generation Atomic Absorption ... Consequently, we were driven by the need to develop an ..... Table 2 Precision and Reproducibility test for Arsenic. Amount of ...

  11. Arsenic on the Hands of Children after Playing in Playgrounds

    National Research Council Canada - National Science Library

    Elena Kwon; Hongquan Zhang; Zhongwen Wang; Gian S. Jhangri; Xiufen Lu; Nelson Fok; Stephan Gabos; Xing-Fang Li; X. Chris Le

    2004-01-01

    .... Limited data from previous studies analyzing arsenic levels in sand samples collected from CCA playgrounds are inconsistent and cannot be directly translated to the amount of children's exposure to arsenic...

  12. Arsenic and the Epigenome: Linked by Methylation(SOT)

    Science.gov (United States)

    Inorganic arsenic (iAs) is an environmental toxicant currently poisoning millions of people worldwide, and chronically-exposed individuals are susceptible to arsenic poisoning, or arsenicosis. In some exposed populations arsenicosis susceptibility is dependent in part on the abil...

  13. Genotoxic Effect of Atrazine, Arsenic, Cadmium and Nitrate ...

    African Journals Online (AJOL)

    ATZ), Cadmium (Cd), Arsenic (As) and Nitrate (NO3) have both estrogenic activity and carcinogenic potential. Atrazine has clastogenic effects and may also act as tumor promoter as it induces the aromatase enzyme. Arsenic and Cadmium ...

  14. 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 ...

  15. Removal of arsenic from drinking water by natural adsorbents

    OpenAIRE

    MD SHAHNOOR ALAM KHAN

    2017-01-01

    The presence of arsenic in groundwater has been reported in many countries across the world and it is a serious threat to public health. The aim of this study was to identify prospective natural materials with high arsenic adsorption capacity and durable hydraulic property to produce adequate flow of water. The comparative study identified Skye sand as the best natural adsorbent. The prototype household filter with Skye sand achieved complete removal of arsenic and iron. Arsenic removal by du...

  16. 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.

  17. Selenium and Arsenic - Nitrate-facilitated Pyrite Oxidation in an Urban Watershed

    Science.gov (United States)

    Sjolin, J.; Meixner, T.; Hibbs, B.; Amrhein, C.; Walker, J.

    2003-12-01

    A century of Orange County urbanization on the Newport Bay / San Diego Creek Watershed has had dramatic impacts on surface geomorphology. Draining of historic wetlands and subsequent channel incision has caused oxidation and mobilization of toxic trace elements accumulated in the former wetlands. Levels of selenium (maximum 270 \\x8Dg/L, median 28 \\x8Dg/L) and arsenic (maximum 40 \\x8Dg/L, median 5 \\x8Dg/L) released to surface waters are as much as 50 times the standard for wildlife toxicity. Additionally field evidence indicates that high levels of nitrate present in the soil (6 mg/kg) and ground water (maximum 55 mg/L, median 7 mg/L), originating in past agricultural activity in the watershed, enhances trace element mobilization via microbially mediated denitrification and pyrite oxidation. The spatial pattern of groundwater concentrations of nitrate, selenium and arsenic suggest an inverse relationship that is indicative of this redox reaction. Preliminary results from a batch study using local vadose zone soils demonstrates a trend for greater mobilization of arsenic by a 200 ppm nitrate solution than by control solution. A positive correlation between sulfate, selenium and arsenic in groundwater samples supports concurrent oxidation and mobilization; it also defines pyrite and related sulfur compounds as candidates for original sequestration in the historic wetland. Ratios of chloride to sulfate as well as sulfur isotopes in groundwater samples show sulfate enrichment indicative of oxidative dissolution processes, possibly of pyrite, as opposed to evaporative concentration or external loading. Elevated bicarbonate concentrations in regions of high selenium and arsenic also support this hypothesis, since acidity generated by pyrite oxidation facilitates calcite dissolution. A positive correlation between arsenic and molybdenum suggests a significant role for surface adsorption of oxidized arsenic and reduced selenium species in controlling trace element

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

    Directory of Open Access Journals (Sweden)

    Noor E-Tabassum

    2006-03-01

    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.

  19. 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.

  20. Laterite-A Potential Alternative for Removal of Groundwater Arsenic ...

    African Journals Online (AJOL)

    Laterite-A Potential Alternative for Removal of Groundwater Arsenic. IMM Rahman, K Iwakabe, J Kawasaki. Abstract. Arsenic removal by heat treated laterite from contaminated water was investigated through batch adsorption experiments. The removal rate was dependent on the initial arsenic concentrations and a high

  1. Linking Genes to Microbial Biogeochemical Cycling: Lessons from Arsenic.

    Science.gov (United States)

    Zhu, Yong-Guan; Xue, Xi-Mei; Kappler, Andreas; Rosen, Barry P; Meharg, Andrew A

    2017-07-05

    The biotransformation of arsenic is highly relevant to the arsenic biogeochemical cycle. Identification of the molecular details of microbial pathways of arsenic biotransformation coupled with analyses of microbial communities by meta-omics can provide insights into detailed aspects of the complexities of this biocycle. Arsenic transformations couple to other biogeochemical cycles, and to the fate of both nutrients and other toxic environmental contaminants. Microbial redox metabolism of iron, carbon, sulfur, and nitrogen affects the redox and bioavailability of arsenic species. In this critical review we illustrate the biogeochemical processes and genes involved in arsenic biotransformations. We discuss how current and future metagenomic-, metatranscriptomic-, metaproteomic-, and metabolomic-based methods will help to decipher individual microbial arsenic transformation processes, and their connections to other biogeochemical cycle. These insights will allow future use of microbial metabolic capabilities for new biotechnological solutions to environmental problems. To understand the complex nature of inorganic and organic arsenic species and the fate of environmental arsenic will require integrating systematic approaches with biogeochemical modeling. Finally, from the lessons learned from these studies of arsenic biogeochemistry, we will be able to predict how the environment changes arsenic, and, in response, how arsenic biotransformations change the environment.

  2. 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. Howeve...

  3. The Arsenic Project: A multidisciplinary Project in Nicaragua

    NARCIS (Netherlands)

    Admiraal, M.; Couasnon, A.; Huijzenveld, T.; Hutten, R.; Schölvinck, O.; Van Veen, N.

    2015-01-01

    In Nicaragua, active research for arsenic started in 1996, after the first case of arsenic poisoning was reported in a rural community. Arsenic concentrations present in drinking water cause chronic poisoning, which depending on the exposure, lead to several life-threatening long term effects. It

  4. DIVERSITY OF ARSENIC METABOLISM IN CULTURED HUMAN CANCER CELL LINES

    Science.gov (United States)

    Diversity of arsenic metabolism in cultured human cancer cell lines. Arsenic has been known to cause a variety of malignancies in human. Pentavalent As (As 5+) is reduced to trivalent As (As3+) which is further methylated by arsenic methyltransferase(s) to monomethylarson...

  5. Arsenic contamination awareness among the rural residents in Bangladesh.

    Science.gov (United States)

    Paul, Bimal Kanti

    2004-10-01

    Arsenic poisoning of tubewell water, which constitutes the primary source of drinking water, has become the greatest health threat to the people of rural Bangladesh. Somewhere between 35 to 57 million people in the country are now suspected of being affected by drinking water contaminated with arsenic. While the Bangladesh government, non-government organizations (NGOs), and bilateral and multilateral assistance agencies are involved in combating this dreadful problem, all of their efforts to date have proceeded without having grassroots information about arsenic poisoning. The objectives of this study are to investigate the level of knowledge rural residents have regarding arsenic poisoning and to identify the correlates of that knowledge. Questionnaire surveys administered among residents of four rural areas in Bangladesh provided the major data source for this study. Twenty villages were selected from moderate and low arsenic risk regions and a total of 356 respondents, 177 from medium risk regions and 179 from low risk regions, were interviewed. Analysis of the survey data reveals that arsenic awareness is currently not widespread in the study villages, particularly in the low arsenic risk region. There are also gaps in arsenic knowledge regarding the diseases caused by arsenic poisoning and mitigating measures available to prevent contamination. This study identified arsenic risk region, level of education, gender, and age as important determinants of arsenic knowledge. The findings of this study will aid in making existing health education programs more effective and in reducing the risk of developing arsenic-related illnesses.

  6. Carbonate ions and arsenic dissolution by groundwater

    Science.gov (United States)

    Kim, M.-J.; Nriagu, J.; Haack, S.

    2000-01-01

    Samples of Marshall Sandstone, a major source of groundwater with elevated arsenic levels in southeast Michigan, were exposed to bicarbonate ion under controlled chemical conditions. In particular, effects of pH and redox conditions on arsenic release were evaluated. The release of arsenic from the aquifer rock was strongly related to the bicarbonate concentration in the leaching solution. The results obtained suggest that the carbonation of arsenic sulfide minerals, including orpiment (As2S3) and realgar (As2S2), is an important process in leaching arsenic into groundwater under anaerobic conditions. The arseno-carbonate complexes formed, believed to be As(CO3)2-, As(CO3)(OH)2-, and AsCO3+, are stable in groundwater. The reaction of ferrous ion with the thioarsenite from carbonation process can result in the formation of arsenopyrite which is a common mineral in arsenic-rich aquifers.Samples of Marshall Sandstone, a major source of groundwater with elevated arsenic levels in southeast Michigan, were exposed to bicarbonate ion under controlled chemical conditions. In particular, effects of pH and redox conditions on arsenic release were evaluated. The release of arsenic from the aquifer rock was strongly related to the bicarbonate concentration in the leaching solution. The results obtained suggest that the carbonation of arsenic sulfide minerals, including orpiment (As2S3) and realgar (As2S2), is an important process in leaching arsenic into groundwater under anaerobic conditions. The arseno-carbonate complexes formed, believed to be As(CO3)2-, As(CO3)(OH)2-, and AsCO3+, are stable in groundwater. The reaction of ferrous ion with the thioarsenite from carbonation process can result in the formation of arsenopyrite which is a common mineral in arsenic-rich aquifers.The role of bicarbonate in leaching arsenic into groundwater was investigated by conducting batch experiments using core samples of Marshall Sandstone from southeast Michigan and different bicarbonate

  7. Ultrastructural cytochemical analysis of intranuclear arsenic inclusions

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, E.M.B.

    1987-01-01

    To establish the chemical composition of the arsenic inclusion, freshly isolated preparations of inclusions and epon-embedded thin sections of inclusions were subjected to ultrastructural cytochemical analysis. Intranuclear inclusions are composed of amorphous, arsenic-containing subunits aligned linearly to form a coiled complex. Lipase, ribonuclease, deoxyribonuclease, trypsin, pepsin, protease, amylase, or ethylenediaminetetraacetic acid (EDTA) was used to digest or chelate these inclusions. Following enzymatic digestion or chelation, the electron opacity of inclusions was compared with that of control sections exposed for equal times to equivalent solutions lacking the enzymes. Exposure to amylase caused a consistent reduction in the electron opacity of thin sections of inclusions and almost complete digestion of the freshly isolated preparations of inclusions. This was indicative of the presence of a carbohydrate moiety within arsenic inclusions. Incubation of inclusions with EDTA resulted in solubilization of freshly isolated and thin-sectioned embedded material. These data indicated that the intranuclear arsenic inclusion is composed of both metallic and carbohydrate moieties, confirming earlier studies which identified arsenic within inclusions using instrumental neutron activation analysis and x-ray microprobe analysis.

  8. Chronic Arsenic Poisoning Probably Caused by Arsenic-Based Pesticides: Findings from an Investigation Study of a Household

    Directory of Open Access Journals (Sweden)

    Yongfang Li

    2016-01-01

    Full Text Available In addition to naturally occurring arsenic, man-made arsenic-based compounds are other sources of arsenic exposure. In 2013, our group identified 12 suspected arsenicosis patients in a household (32 living members. Of them, eight members were diagnosed with skin cancer. Interestingly, all of these patients had lived in the household prior to 1989. An investigation revealed that approximately 2 tons of arsenic-based pesticides had been previously placed near a well that had supplied drinking water to the family from 1973 to 1989. The current arsenic level in the well water was 620 μg/L. No other high arsenic wells were found near the family’s residence. Based on these findings, it is possible to infer that the skin lesions exhibited by these family members were caused by long-term exposure to well water contaminated with arsenic-based pesticides. Additionally, biochemical analysis showed that the individuals exposed to arsenic had higher levels of aspartate aminotransferase and γ-glutamyl transpeptidase than those who were not exposed. These findings might indicate the presence of liver dysfunction in the arsenic-exposed individuals. This report elucidates the effects of arsenical compounds on the occurrence of high levels of arsenic in the environment and emphasizes the severe human health impact of arsenic exposure.

  9. Chronic Arsenic Poisoning Probably Caused by Arsenic-Based Pesticides: Findings from an Investigation Study of a Household.

    Science.gov (United States)

    Li, Yongfang; Ye, Feng; Wang, Anwei; Wang, Da; Yang, Boyi; Zheng, Quanmei; Sun, Guifan; Gao, Xinghua

    2016-01-16

    In addition to naturally occurring arsenic, man-made arsenic-based compounds are other sources of arsenic exposure. In 2013, our group identified 12 suspected arsenicosis patients in a household (32 living members). Of them, eight members were diagnosed with skin cancer. Interestingly, all of these patients had lived in the household prior to 1989. An investigation revealed that approximately 2 tons of arsenic-based pesticides had been previously placed near a well that had supplied drinking water to the family from 1973 to 1989. The current arsenic level in the well water was 620 μg/L. No other high arsenic wells were found near the family's residence. Based on these findings, it is possible to infer that the skin lesions exhibited by these family members were caused by long-term exposure to well water contaminated with arsenic-based pesticides. Additionally, biochemical analysis showed that the individuals exposed to arsenic had higher levels of aspartate aminotransferase and γ-glutamyl transpeptidase than those who were not exposed. These findings might indicate the presence of liver dysfunction in the arsenic-exposed individuals. This report elucidates the effects of arsenical compounds on the occurrence of high levels of arsenic in the environment and emphasizes the severe human health impact of arsenic exposure.

  10. Arsenic Speciation in Blue Mussels (Mytilus edulis) Along a Highly Contaminated Arsenic Gradient

    Energy Technology Data Exchange (ETDEWEB)

    Whaley-Martin, K.J.; Koch, I.; Moriarty, M.; Reimer, K.J. (Royal)

    2012-11-01

    Arsenic is naturally present in marine ecosystems, and these can become contaminated from mining activities, which may be of toxicological concern to organisms that bioaccumulate the metalloid into their tissues. The toxic properties of arsenic are dependent on the chemical form in which it is found (e.g., toxic inorganic arsenicals vs nontoxic arsenobetaine), and two analytical techniques, high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) and X-ray absorption spectroscopy (XAS), were used in the present study to examine the arsenic species distribution in blue mussels (Mytilus edulis) obtained from an area where there is a strong arsenic concentration gradient as a consequence of mining impacted sediments. A strong positive correlation was observed between the concentration of inorganic arsenic species (arsenic compounds with no As-C bonds) and total arsenic concentrations present in M. edulis tissues (R{sup 2} = 0.983), which could result in significant toxicological consequences to the mussels and higher trophic consumers. However, concentrations of organoarsenicals, dominated by arsenobetaine, remained relatively constant regardless of the increasing As concentration in M. edulis tissue (R{sup 2} = 0.307). XANES bulk analysis and XAS two-dimensional mapping of wet M. edulis tissue revealed the presence of predominantly arsenic-sulfur compounds. The XAS mapping revealed that the As(III)-S and/or As(III) compounds were concentrated in the digestive gland. However, arsenobetaine was found in small and similar concentrations in the digestive gland as well as the surrounding tissue suggesting arsenobetaine may being used in all of the mussel's cells in a physiological function such as an intracellular osmolyte.

  11. Inorganic arsenic in drinking water accelerates N-butyl-N-(4-hydroxybutyl)nitrosamine-induced bladder tissue damage in mice

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Paul-Yann [Department of Pathology, Chang Gung Memorial Hospital at Chiayi, Chang Gung University, Chiayi, Taiwan (China); Lin, Yung-Lun; Huang, Chin-Chin; Chen, Sin-Syu [Department of Microbiology, Immunology and Biopharmaceuticals, College of Life Sciences, National Chiayi University, Chiayi, Taiwan (China); Liu, Yi-Wen, E-mail: ywlss@mail.ncyu.edu.tw [Department of Microbiology, Immunology and Biopharmaceuticals, College of Life Sciences, National Chiayi University, Chiayi, Taiwan (China)

    2012-02-15

    Epidemiological studies have revealed that exposure to an arsenic-contaminated environment correlates with the incidence of bladder cancer. Bladder cancer is highly recurrent after intravesical therapy, and most of the deaths from this disease are due to invasive metastasis. In our present study, the role of inorganic arsenic in bladder carcinogenesis is characterized in a mouse model. This work provides the first evidence that inorganic arsenic in drinking water promotes N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-induced bladder tissue damage, including the urothelium and submucosal layer. This damage to the bladder epithelium induced by BBN includes thickening of the submucosal layer, the loss of the glycosaminoglycan layer and an increase in both the deoxyguanosine oxidation and cytosine methylation levels in the DNA. Further, when 10 ppm inorganic arsenic is combined with BBN, the number of bladder submucosal capillaries is increased. In addition, inorganic arsenic also increases the deoxyguanosine oxidation level, alters the cytosine methylation state, decreases the activities of glutathione reductase and glucose-6-phosphate dehydrogenase, decreases the protein expression of NAD(P)H quinone oxidoreductase-1 (NQO-1) and increases the protein expression of specific protein 1 (Sp1) in bladder tissues. In summary, our data reveal that inorganic arsenic in drinking water promotes the BBN-induced pre-neoplastic damage of bladder tissue in mice, and that the 8-hydroxy-2′-deoxyguanosine, 5-methylcytosine, NQO-1 protein and Sp1 protein levels may be pre-neoplastic markers of bladder tumors. -- Highlights: ► The role of inorganic arsenic in bladder carcinogenesis is characterized in mice. ► We examine the changes in the histology and biochemistry of bladder tissues. ► Inorganic arsenic enhances BBN-induced DNA oxidation while decreases BBN-induced DNA methylation in the mouse bladder. ► Inorganic arsenic alters the activities of the anti-oxidant enzymes in

  12. Monitoring of arsenic in aquatic plants, water, and sediment of wastewater treatment ponds at the Mae Moh Lignite power plant, Thailand.

    Science.gov (United States)

    Nateewattana, Jomjun; Trichaiyaporn, Siripen; Saouy, Maliwan; Nateewattana, Jintapat; Thavornyutikarn, Prasak; Pengchai, Petch; Choonluchanon, Somporn

    2010-06-01

    Mae Moh is a risky area for arsenic contamination caused by the effluent from biowetland ponds in Mae Moh lignite-fuelled power plant. The objective of this study was to investigate the arsenic concentrations of Mae Moh biowetland ponds and determine the main factors which are important for arsenic phytoremediation in the treatment system. The result revealed that arsenic concentrations in the supernant were in the range of less than 1.0 microg As L(-1) to 2.0 microg As L(-1) while those in the sediment were in the range of 25-200 microg As kg soil(-1). Both values were below the Thailand national standard of 0.25 mg As L(-1) for water and 27 mg As kg soil(-1) for the soil. Arsenic accumulation in the biomass of 5 aquatic plants at the biowetland ponds ranged from 123.83 to 280.53 mg As kgPlant(-1). Regarding the result of regression analysis (R (2) = 0.474 to 0.954), high concentrations of organic matter and other soluble ions as well as high pH value in the sediment could significantly enhance the removal of soluble arsenic in the wetland ponds. From the regression equation of accumulated arsenic concentration in each aquatic plant, Eichhornia crassipes (Mart.) Solms. (R (2) = 0.954), Ipomoea aquatica Forsk. (R (2) = 0.850), and Typha angustifolia (L.) (R (2) = 0.841) were found to be preferable arsenic removers for wastewater treatment pond in the condition of low Eh value and high content of solid phase EC and phosphorus. On the other hand, Canna glauca (L.) (R (2) = 0.749) appeared to be favorable arsenic accumulator for the treatment pond in the condition of high Eh value and high concentration of soluble EC.

  13. Arsenic analysis II: rapid separation and quantification of inorganic arsenic plus metabolites and arsenobetaine from urine.

    Science.gov (United States)

    Nixon, D E; Moyer, T P

    1992-12-01

    We describe the rapid separation of inorganic arsenic plus metabolites from arsenobetaine or seafood arsenic in urine. Traditional, high-pressure liquid chromatography is replaced by disposable silica-based cation-exchange cartridges for this separation. Both fractions are quickly separated and collected for analysis by atomic absorption spectrophotometry. Analytical recovery of both fractions is > or = 95%, with an overall precision (CV) ranging from 1.6% to 6.4%. Using this method, we correctly identified the sources of arsenic exposure, whether of inorganic or seafood origin, in 11 urine specimens supplied by the Centre de Toxicologie du Quebec.

  14. Arsenic uptake in bacterial calcite

    Science.gov (United States)

    Catelani, Tiziano; Perito, Brunella; Bellucci, Francesco; Lee, Sang Soo; Fenter, Paul; Newville, Matthew; Rimondi, Valentina; Pratesi, Giovanni; Costagliola, Pilario

    2018-02-01

    Bio-mediated processes for arsenic (As) uptake in calcite were investigated by means of X-ray Diffraction (XRD) and X-ray Absorption Spectroscopy (XAS) coupled with X-ray Fluorescence measurements. The environmental bacterial strain Bacillus licheniformis BD5, sampled at the Bullicame Hot Springs (Viterbo, Central Italy), was used to synthesize calcite from As-enriched growth media. Both liquid and solid cultures were applied to simulate planktonic and biofilm community environments, respectively. Bacterial calcite samples cultured in liquid media had an As enrichment factor (Kd) 50 times higher than that from solid media. The XRD analysis revealed an elongation of the crystal lattice along the c axis (by 0.03 Å) for biogenic calcite, which likely resulted from the substitution of larger arsenate for carbonate in the crystal. The XAS data also showed a clear difference in the oxidation state of sorbed As between bacterial and abiotic calcite. Abiotic chemical processes yielded predominantly As(V) uptake whereas bacterial precipitation processes led to the uptake of both As(III) and As(V). The presence of As(III) in bacterial calcite is proposed to result from subsequent reduction of arsenate to arsenite by bacterial activities. To the best of our knowledge, this is the first experimental observation of the incorporation of As(III) in the calcite crystal lattice, revealing a critical role of biochemical processes for the As cycling in nature.

  15. Arsenic uptake in bacterial calcite

    Energy Technology Data Exchange (ETDEWEB)

    Catelani, Tiziano; Perito, Brunella; Bellucci, Francesco; Lee, Sang Soo; Fenter, Paul; Newville, Matthew G.; Rimondi, Valentina; Pratesi, Giovanni; Costagliola, Pilario

    2018-02-01

    Bio-mediated processes for arsenic (As) uptake in calcite were investigated by means of X-ray Diffraction (XRD) and Xray Absorption Spectroscopy (XAS) coupled with X-ray Fluorescence measurements. The environmental bacterial strain Bacillus licheniformis BD5, sampled at the Bullicame Hot Springs (Viterbo, Central Italy), was used to synthesize calcite from As-enriched growth media. Both liquid and solid cultures were applied to simulate planktonic and biofilm community environments, respectively. Bacterial calcite samples cultured in liquid media had an As enrichment factor (Kd) 50 times higher than that from solid media. The XRD analysis revealed an elongation of the crystal lattice along the c axis (by 0.03Å) for biogenic calcite, which likely resulted from the substitution of larger arsenate for carbonate in the crystal. The XAS data also showed a clear difference in the oxidation state of sorbed As between bacterial and abiotic calcite. Abiotic chemical processes yielded predominantly As(V) uptake whereas bacterial precipitation processes led to the uptake of both As(III) and As(V). The presence of As(III) in bacterial calcite is proposed to result from subsequent reduction of arsenate to arsenite by bacterial activities. To the best of our knowledge, this is the first experimental observation of the incorporation of As(III) in the calcite crystal lattice, revealing a critical role of biochemical processes for the As cycling in nature.

  16. MicroRNA-dependent regulation of PTEN after arsenic trioxide treatment in bladder cancer cell line T24.

    Science.gov (United States)

    Cao, Yan; Yu, Shi-Liang; Wang, Yan; Guo, Gui-Ying; Ding, Qiang; An, Rui-Hua

    2011-02-01

    Arsenic trioxide has shown remarkable biological activity against bladder cancer in some clinical studies. However, the mechanism of its action is unknown. Our aim was to find the relationship between miRNAs and arsenic trioxide treatment by using T24 human bladder carcinoma cells. By performing microRNA microarray and quantitative real-time PCR after ATO treatment, we found that expression levels of several miRNAs, in particular, miRNA-19a, were significantly decreased in T24 cell line. Furthermore, cell proliferation assay, flow cytometry analysis, prediction of miRNA targets, Western blot analysis, and luciferase reporter assay were performed to determine the role of mir-19a in affecting the biological behaviors of T24 cells. Several miRNAs were up-regulated or down-regulated in T24 cells treated with arsenic trioxide compared to their controls. If only changes above two folds were considered, two miRNAs were identified, miRNA-19a was down-regulated, while miRNA-222* was up-regulated. Among them, knockdown of miRNA-19a by anti-miRNA-19a transfection showed a positive therapeutic effect in bladder cancer cells by inhibiting cell growth and inducing cell apoptosis targeting PTEN through the PTEN/Akt pathway. Besides this, a synergy effect was detected between knockdown of miRNA-19a and arsenic trioxide. Arsenic trioxide altered miRNA expression profile in T24 cells. It seems miRNA-19a plays a critical role in the mechanism of arsenic trioxide treatment in bladder cancer. The synergy effect between miRNA-19a and arsenic trioxide that advocates targeting the mir-19a may represent a potential approach to enhance the efficacy and safety of ATO to treat bladder cancer by a decrease in dose.

  17. Effects of arsenate, chromate, and sulfate on arsenic and chromium uptake and translocation by arsenic hyperaccumulator Pteris vittata L.

    Science.gov (United States)

    de Oliveira, Letúzia Maria; Ma, Lena Q; Santos, Jorge A G; Guilherme, Luiz R G; Lessl, Jason T

    2014-01-01

    We investigated effects of arsenate (AsV), chromate (CrVI) and sulfate on As and Cr uptake and translocation by arsenic hyperaccumulator Pteris vittata (PV), which was exposed to AsV, CrVI and sulfate at 0, 0.05, 0.25 or 1.25 mM for 2-wk in hydroponic system. PV was effective in accumulating large amounts of As (4598 and 1160 mg/kg in the fronds and roots at 0.05 mM AsV) and Cr (234 and 12,630 mg/kg in the fronds and roots at 0.05 mM CrVI). However, when co-present, AsV and CrVI acted as inhibitors, negatively impacting their accumulation in PV. Arsenic accumulation in the fronds was reduced by 92% and Cr by 26%, indicating reduced As and Cr translocation. However, addition of sulfate increased uptake and translocation of As by 26-28% and Cr by 1.63 fold. This experiment demonstrated that As and Cr inhibited each other in uptake and translocation by PV but sulfate enhanced As and Cr uptake and translocation by PV. Published by Elsevier Ltd.

  18. Arsenic species in solutions for parenteral nutrition.

    Science.gov (United States)

    Bohrer, Denise; do Nascimento, Paulo Cícero; Becker, Emilene; de Carvalho, Leandro Machado; Dessuy, Morgana

    2005-01-01

    In spite of its high toxicity, arsenic is a common contaminant in pharmaceuticals. This is stated by pharmacopoeias' monographs where it is not generically included with other heavy metals, but has its own specifications. Arsenic should not exceed 0.1 mg/L in most pharmaceutical products for IV administration. This limit, however, was established without taking into consideration the specific arsenic species which contribute to this amount. In this work, the presence of arsenite and arsenate species in solutions of amino acids, salts, vitamins, and lipids commercialized for IV administration was investigated. The measurements were done by hydride generation atomic absorption spectrometry. The results showed that all commercial formulations contain both arsenic species in some level; however, the total arsenic content exceeded the allowed limit in only a few samples. Calcium gluconate, sodium bicarbonate, heparin, and vitamin solutions were the most contaminated, presenting total arsenic concentration ranging from 62 to 249 microg/L. The most important finding, however, was the different ratios As(V)/As(III) among the formulations. Whereas practically only As(V) was found in ampoules containing water for injection and salt solutions (NaCl, KC1, phosphates), As(III) predominated in solutions of vitamins, gluconate, and glucose. As these are reducing substances, we investigated the possibility of their reaction with As(V) and its conversion into As(III). The heating of As(V) in the presence of gluconate, glucose, ascorbic acid, methionine, isoleucine, sodium chloride, and pure water, in autoclave for 15 minutes, showed that, whereas no As(III) was found in pure water and sodium chloride solution, approximately 50% of As(V) was converted into As(III) in the remainder of the solutions. The results showed that As(V), the main species in these formulations, may be converted into As(III), depending on the presence of reducing substances among the formulation constituents.

  19. ARSENIC CONTAMINATION IN DRINKING WATER: AN ASSESSMENT FOR TURKEY

    Directory of Open Access Journals (Sweden)

    Meltem BİLİCİ ÇALIŞKAN

    2009-01-01

    Full Text Available Arsenic is one of the most abundant elements in the earth's crust and classified as a non-metal or a metalloid. Arsenic is toxic and carcinogen and in the environment occurs from both natural and anthropogenic sources. In the aqueous environment inorganic arsenic appears commonly in forms of arsenite (As(III and arsenate (As(V. pH, redox potential, and the presence of complexing ions such as ions of sulfur, iron, and calcium determine the arsenic valence and speciation. Because of the naturally occurring arsenic contamination in groundwater in many parts of the world many people have faced with risk of arsenic poisoning. In Turkey especially in the west regions, natural water sources contained much higher levels of arsenic than maximum contaminated level (MCL set (10 ?g/L were determined. In this study, arsenic problem and its reasons in Turkey were investigated. For this purpose, arsenic analyses were carried out and higher levels of arsenic than MCL was detected in some regions of Izmir. High levels of arsenic in these natural waters were considered to be associated with the dissolution of some minerals and rock formation.

  20. 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.

  1. The Case for Visual Analytics of Arsenic Concentrations in Foods

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    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.

  2. Anthropogenic Cycles of Arsenic in Mainland China: 1990-2010.

    Science.gov (United States)

    Shi, Ya-Lan; Chen, Wei-Qiang; Wu, Shi-Liang; Zhu, Yong-Guan

    2017-02-07

    Arsenic (As) is a trace element in the global environment with toxicity to both humans and ecosystem. This study characterizes China's historical anthropogenic arsenic cycles (AACs) from 1990 to 2010. Key findings include the following: (1) the scale of China's AACs grew significantly during the studied period, making China the biggest miner, producer, and user of arsenic today; (2) the majority of arsenic flows into China's anthroposphere are the impurity of domestically mined nonferrous metal ores, which far exceeds domestic intentional demands; (3) China has been a net exporter of arsenic trioxide and arsenic metalloid, thus suffering from the environmental burdens of producing arsenic products for other economies; (4) the growth of arsenic use in China is driven by simultaneous increases in many applications including glass making, wood preservatives, batteries, semiconductors, and alloys, implying the challenge for regulating arsenic uses in multiple applications/industries at the same time; (5) the dissipative arsenic emissions resulting from intentional applications are at the same order of magnitude as atmospheric emissions from coal combustion, and their threats to human and ecosystem health can spread widely and last years to decades. Our results demonstrate that the characterization of AACs is indispensable for developing a complete arsenic emission inventory.

  3. Inorganic arsenic levels in baby rice are of concern

    Energy Technology Data Exchange (ETDEWEB)

    Meharg, Andrew A. [School of Biological Sciences, University of Aberdeen, Cruickshank Building, St. Machar Drive, Aberdeen AB24 3UU (United Kingdom)], E-mail: a.meharg@abdn.ac.uk; Sun, Guoxin [Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Williams, Paul N. [School of Biological Sciences, University of Aberdeen, Cruickshank Building, St. Machar Drive, Aberdeen AB24 3UU (United Kingdom); Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Adomako, Eureka; Deacon, Claire [School of Biological Sciences, University of Aberdeen, Cruickshank Building, St. Machar Drive, Aberdeen AB24 3UU (United Kingdom); Zhu, Yong-Guan [Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Feldmann, Joerg; Raab, Andrea [Department of Chemistry, University of Aberdeen, Meston Building, Meston Walk, Aberdeen AB24 3UE (United Kingdom)

    2008-04-15

    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 {mu}g/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.

  4. 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.

  5. 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.

  6. Biological filtration for removal of arsenic from drinking water.

    Science.gov (United States)

    Pokhrel, Damodar; Viraraghavan, Thiruvenkatachari

    2009-04-01

    The main objective of the study was to find a suitable iron to arsenic ratio in water to reduce arsenic to 5 microg/L or lower through sand filtration. Experiments were conducted by varying the quantity of iron(II) while keeping the arsenic concentration at 100 microg/L. A mixture of iron (II) and arsenic at different ratios (10:1, 20:1, 30:1 and 40:1) was pumped to the sand filters in a down flow mode and effluent arsenic and iron were analyzed. It was found that a ratio of iron to arsenic of 40:1 was necessary to ensure an effluent arsenic concentration of 5 microg/L or lower. Iron in the filtrate was found to be below 0.1 mg/L at all times.

  7. Coping with arsenic-based pesticides on Dine (Navajo) textiles

    Science.gov (United States)

    Anderson, Jae R.

    Arsenic-based pesticide residues have been detected on Arizona State Museum's (ASM) Dine (Navajo) textile collection using a handheld portable X-ray (pXRF) spectrometer. The removal of this toxic pesticide from historic textiles in museums collections is necessary to reduce potential health risks to Native American communities, museum professionals, and visitors. The research objective was divided into three interconnected stages: (1) empirically calibrate the pXRF instrument for arsenic contaminated cotton and wool textiles; (2) engineer an aqueous washing treatment exploring the effects of time, temperature, agitation, and pH conditions to efficiently remove arsenic from wool textiles while minimizing damage to the structure and properties of the textile; (3) demonstrate the devised aqueous washing treatment method on three historic Navajo textiles known to have arsenic-based pesticide residues. The preliminary results removed 96% of arsenic from a high arsenic concentration (~1000 ppm) textile opposed to minimal change for low arsenic concentration textiles (<100 ppm).

  8. [Tissue distribution of arsenic of liushen pills and realgar].

    Science.gov (United States)

    Zhang, Qing-Li; Wu, Qian; Xie, Yuan-Yuan; Shen, Lian-Zhong; Fan, Min-Wei; Liang, Qiong-Lin; Wang, Yi-Ming; Luo, Guo-An

    2011-06-01

    This study is to report the tissue distribution of arsenic after giving different doses of realgar and Liushen pills to Beagle dogs, in order to provide basis for the safety evaluation of Liushen pills. ICP-MS was used to measure arsenic concentration, and HPLC-ICP-MS was used to analyze arsenic speciation. The concentration of total arsenic and As(III) + DMA (arsenite + dimethylarsenic acid) increased with dosing of realgar. Total arsenic concentration in most tissues and As(III) + DMA concentration in all tissues of Liushen pills group are lower than that of realgar group, but AsB concentration in liver, spleen and kidney of Liushen pills group increased. The concentration of total arsenic showed a dose-dependent manner with dosage administered. It was indicated that components in Liushen pills can reduce solubility of arsenic in realgar, which may decrease toxicity of realgar.

  9. 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.

  10. Biosensors for Inorganic and Organic Arsenicals

    Directory of Open Access Journals (Sweden)

    Jian Chen

    2014-11-01

    Full Text Available Arsenic is a natural environmental contaminant to which humans are routinely exposed and is strongly associated with human health problems, including cancer, cardiovascular and neurological diseases. To date, a number of biosensors for the detection of arsenic involving the coupling of biological engineering and electrochemical techniques has been developed. The properties of whole-cell bacterial or cell-free biosensors are summarized in the present review with emphasis on their sensitivity and selectivity. Their limitations and future challenges are highlighted.

  11. 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.

  12. Arsenic exposure and intestinal microbiota in children from Sirajdikhan, Bangladesh.

    Science.gov (United States)

    Dong, Xiaoxi; Shulzhenko, Natalia; Lemaitre, Julien; Greer, Renee L; Peremyslova, Kate; Quamruzzaman, Quazi; Rahman, Mahmudar; Hasan, Omar Sharif Ibn; Joya, Sakila Afroz; Golam, Mostofa; Christiani, David C; Morgun, Andriy; Kile, Molly L

    2017-01-01

    Arsenic has antimicrobial properties at high doses yet few studies have examined its effect on gut microbiota. This warrants investigation since arsenic exposure increases the risk of many diseases in which gut microbiota have been shown to play a role. We examined the association between arsenic exposure from drinking water and the composition of intestinal microbiota in children exposed to low and high arsenic levels during prenatal development and early life. 16S rRNA gene sequencing revealed that children with high arsenic exposure had a higher abundance of Proteobacteria in their stool compared to matched controls with low arsenic exposure. Furthermore, whole metagenome shotgun sequencing identified 332 bacterial SEED functions that were enriched in the high exposure group. A separate model showed that these genes, which included genes involved in virulence and multidrug resistance, were positively correlated with arsenic concentration within the group of children in the high arsenic group. We performed reference free genome assembly, and identified strains of E.coli as contributors to the arsenic enriched SEED functions. Further genome annotation of the E.coli genome revealed two strains containing two different arsenic resistance operons that are not present in the gut microbiome of a recently described European human cohort (Metagenomics of the Human Intestinal Tract, MetaHIT). We then performed quantification by qPCR of two arsenic resistant genes (ArsB, ArsC). We observed that the expression of these two operons was higher among the children with high arsenic exposure compared to matched controls. This preliminary study indicates that arsenic exposure early in life was associated with altered gut microbiota in Bangladeshi children. The enrichment of E.coli arsenic resistance genes in the high exposure group provides an insight into the possible mechanisms of how this toxic compound could affect gut microbiota.

  13. Arsenic in marine mammals, seabirds, and sea turtles.

    Science.gov (United States)

    Kunito, Takashi; Kubota, Reiji; Fujihara, Junko; Agusa, Tetsuro; Tanabe, Shinsuke

    2008-01-01

    Although there have been numerous studies on arsenic in low-trophic-level marine organisms, few studies exist on arsenic in marine mammals, seabirds, and sea turtles. Studies on arsenic species and their concentrations in these animals are needed to evaluate their possible health effects and to deepen our understanding of how arsenic behaves and cycles in marine ecosystems. Most arsenic in the livers of marine mammals, seabirds, and sea turtles is AB, but this form is absent or occurs at surprisingly low levels in the dugong. Although arsenic levels were low in marine mammals, some seabirds, and some sea turtles, the black-footed albatross and hawksbill and loggerhead turtles showed high concentrations, comparable to those in marine organisms at low trophic levels. Hence, these animals may have a specific mechanism for accumulating arsenic. Osmoregulation in these animals may play a role in the high accumulation of AB. Highly toxic inorganic arsenic is found in some seabirds and sea turtles, and some evidence suggests it may act as an endocrine disruptor, requiring new and more detailed studies for confirmation. Furthermore, DMA(V) and arsenosugars, which are commonly found in marine animals and marine algae, respectively, might pose risks to highly exposed animals because of their tendency to form reactive oxygen species. In marine mammals, arsenic is thought to be mainly stored in blubber as lipid-soluble arsenicals. Because marine mammals occupy the top levels of their food chain, work to characterize the lipid-soluble arsenicals and how they cycle in marine ecosystems is needed. These lipid-soluble arsenicals have DMA precursors, the exact structures of which remain to be determined. Because many more arsenicals are assumed to be present in the marine environment, further advances in analytical capabilities can and will provide useful future information on the transformation and cycling of arsenic in the marine environment.

  14. 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

  15. Effective adsorbent for arsenic removal: core/shell structural nano zero-valent iron/manganese oxide.

    Science.gov (United States)

    Bui, Trung Huu; Kim, Choonsoo; Hong, Sung Pil; Yoon, Jeyong

    2017-11-01

    Recently, nano zero-valent iron (nZVI) has emerged as an effective adsorbent for the removal of arsenic from aqueous solutions. However, its use in various applications has suffered from reactivity loss resulting in a decreased efficiency. Thus, the aim of this study was to develop an effective arsenic adsorbent as a core/shell structural nZVI/manganese oxide (or nZVI/Mn oxide) to minimize the reactivity loss of the nZVI. As the major result, the arsenic adsorption capacities of the nZVI/Mn oxide for As(V) and As(III) were approximately two and three times higher than that of the nZVI, respectively. In addition, the As(V) removal efficiency of the nZVI/Mn oxide was maintained through 4 cycles of regeneration whereas that of the nZVI was decreased significantly. The enhanced reactivity and reusability of the nZVI/Mn oxide can be successfully explained by the synergistic interaction of the nZVI core and manganese oxide shell, in which the manganese oxides participate in oxidation reactions with corroded Fe(2+) and subsequently retard the release of aqueous iron providing additional surface sites for arsenic adsorption. In summary, this study reports the successful fabrication of a core/shell nZVI/Mn oxide as an effective adsorbent for the removal of arsenic from aqueous solutions.

  16. Influence of phosphate on toxicity and bioaccumulation of arsenic in a soil isolate of microalga Chlorella sp.

    Science.gov (United States)

    Bahar, Md Mezbaul; Megharaj, Mallavarapu; Naidu, Ravi

    2016-02-01

    In this study, the toxicity, biotransformation and bioaccumulation of arsenite and arsenate in a soil microalga, Chlorella sp., were investigated using different phosphate levels. The results indicated that arsenate was highly toxic than arsenite to the alga, and the phosphate limitation in growth media greatly enhanced arsenate toxicity. The uptake of arsenate in algal cells was more than that of arsenite, and the predominant species in the growth media was arsenate after 8 days of exposure to arsenite or arsenate, indicating arsenite oxidation by this microalga. Arsenate reduction was also observed when the alga was incubated in a phosphate-limiting growth medium. Similar to the process of biotransformation, the alga accumulated more arsenic when it was exposed to arsenate and preferably more in a phosphate-limiting condition. Although phosphate significantly influences the biotransformation and bioaccumulation of arsenic, the oxidizing ability and higher accumulation capacity of this alga have great potential for its application in arsenic bioremediation.

  17. 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

  18. 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.

  19. 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.

  20. Influence of arsenic and cyanobacteria co-exposure on plasmatic parameters of rainbow trout (Oncorhynchus mykiss W.).

    Science.gov (United States)

    Kopp, Radovan; Mares, Jan; Soukupova, Zdenka; Navratil, Stanislav; Palikova, Miroslava

    2014-01-01

    Fish can be exposed under environmental conditions to multiple stressors including natural toxins and environmental or feed contamination at the same time. This study brings new knowledge about the effects of controlled exposure to multiple stressors in fish. The aim of this study was to test the hypothesis that influence of cyanobacterial biomass and arsenic in feed can combine to enhance the effects on fish. Rainbow trouts were sorted into six groups, each with 25 specimens: control group (fed with commercial feed), groups exposed to toxic cyanobacterial biomass (81 mg x kg(-1) MCs of feed), two groups exposed to arsenic (concentration of 5 mg x kg(-1), and 50 mg x kg(-1) of fish feed) and two groups exposed to combination of cyanobacterial biomass and arsenic in two concentrations mentioned above. The experiment lasted 30 days. During the experiment we evaluated the influence of co-exposure on plasmatic parameters mentioned above. Samples were collected on days 10, 20 and 30 of exposure. Biochemical analysis revealed a significant decrease in calcium (T20) and an increase in natrium (T10) and chlorides (T10) values in combined cyanobacterial and arsenic exposures. Our results showed a significant decrease in the values of magnesium after exposure to higher concentration of arsenic compared to control and feeding with addition of cyanobacterial biomass groups. The changes of other monitored plasmatic parameters were not significantly increased or decreased in comparison with controls. Our results confirmed the hypothesis that influence of toxic cyanobacterial biomass and a chemical agent represented by arsenic can combine to enhance the effects on fish. This work originally shows that while the single agents in sub-lethal doses do not cause changes in the plasmatic parameters, their co-exposure leads to the significantly decrease or increase of the electrolytes of rainbow trout.

  1. Arsenic in rice: A cause for concern

    DEFF Research Database (Denmark)

    Hojsak, Iva; Braegger, Christian; Bronsky, Jiri

    2015-01-01

    Inorganic arsenic intake is likely to affect long-term health. High concentrations are found in some rice-based foods and drinks widely used in infants and young children. In order to reduce exposure we recommend avoidance of rice drinks for infants and young children. For all rice products, strict...

  2. How prokaryotes deal with arsenic(†).

    Science.gov (United States)

    Slyemi, Djamila; Bonnefoy, Violaine

    2012-12-01

    Arsenic is a notorious poison classified as a carcinogen, a teratogen and a clastogen that ranks number one on the Environmental Protection Agency's priority list of drinking water contaminants. It is ubiquitous and relatively abundant in the Earth's crust. Its mobilization in waters by weathering, volcanic, anthropogenic or biological activities represents a major hazard to public health, exemplified in India and Bangladesh where 50 million people are acutely at risk. Since basically the origin of life, microorganisms have been exposed to this toxic compound and have evolved a variety of resistance mechanisms, such as extracellular precipitation, chelation, intracellular sequestration, active extrusion from the cell or biochemical transformation (redox or methylation). Arsenic efflux systems are widespread and are found in nearly all organisms. Some microorganisms are also able to utilize this metalloid as a metabolic energy source through either arsenite oxidation or arsenate reduction. The energy metabolism involving redox reactions of arsenic has been suggested to have evolved during early life on Earth. This review highlights the different systems evolved by prokaryotes to cope with arsenic and how they participate in its biogeochemical cycle. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  3. EFFECTS OF ARSENIC EXPOSURE IN HUMAN HEALTH

    Directory of Open Access Journals (Sweden)

    Aline Sueli de Lima Rodrigues

    2008-10-01

    Full Text Available In recent years, ingestion of inorganic arsenic from drinking water has emerged as an important public health concern. It enters drinking water supplies from natural deposits in the earth or from agricultural and industrial practices, mainly the mining. The health consequences of chronic arsenic exposure include increased risk for various forms of cancer and numerous pathologic effects, such as cutaneous effects (hyperpigmentation and hyperkeratoses, gastrointestinal effects, vascular effects, diabetes mellitus, and peripheral neuropathy. This way, this study presents through a critical revision of the literature, the more relevant current aspects on the immunological consequences, carcinogenic and resulting genetics of the human intoxication for arsenic. They were identified and analyzed 50 works published on the subject among the years of 1979 and 2008, being used as main sources LILACS-BIREME MEDLINE/Index Medicus, SciELO and PubMed. The specific Arsênio e saúde humana effects of the intoxication for arsenic about the human health are not still completely elucidated. Thus, is possible that this element affects functions still unknown, becoming important the scientificexploration on the subject.

  4. Biosorptive removal of arsenic from drinking water.

    Science.gov (United States)

    Pandey, Piyush Kant; Choubey, Shweta; Verma, Yashu; Pandey, Madhurima; Chandrashekhar, K

    2009-01-01

    A biomass derived from the plant Momordica charantia has been found to be very efficient in arsenic(III) adsorption. An attempt was made to use this biomass for arsenic(III) removal under different conditions. The parameters optimized were contact time (5-150 min), pH (2-11), concentration of adsorbent (1-50 g/l), concentration of adsorbate (0.1-100mg/l), etc. It was observed that the pH had a strong effect on biosorption capacity. The optimum pH obtained for arsenic adsorption was 9. The influence of common ions such as Ca(2+), Mg(2+), Cd(2+), Se(4+), Cl(-), SO(4)(2-), and HCO(3)(-), at concentrations varying from 5 to 1000 mg/l was investigated. To establish the most appropriate correlation for the equilibrium curves, isotherm studies were performed for As(III) ion using Freundlich and Langmuir adsorption isotherms. The pattern of adsorption fitted well with both models. The biomass of M. charantia was found to be effective for the removal of As(III) with 88% sorption efficiency at a concentration of 0.5mg/l of As(III) solution, and thus uptake capacity is 0.88 mg As(III)/gm of biomass. It appears that this biomass should be used as a palliative food item. Further it also appears that the dietary habits may play a role in the toxic effects of ingested arsenic.

  5. Grain Unloading Of Arsenic Species In Rice

    Science.gov (United States)

    Rice (Oryza sativa) is the staple food for over half the world's population yet may represent a significant dietary source of inorganic arsenic (As), a nonthreshold, class 1 human carcinogen. Rice grain As is dominated by the inorganic species, and the organic species dim...

  6. Arsenic immobilization of Teniente furnace dust

    Energy Technology Data Exchange (ETDEWEB)

    Ichimura, R. [Japan Oil, Gas, and Metals National Corp., Kawasaki (Japan); Tateiwa, H. [Mitsui Mining and Smelting Co. Ltd., Saitama (Japan); Almendares, C. [Centro de Investigacion Minera y Metalurgica, Santiago (Chile); Sanchez, G. [CODELCO, Santiago (Chile). Division Ventanas

    2007-07-01

    A 5-year joint Japanese-Chilean project to modify the treatment of furnace dust from a converter in Chile producing harmful amounts of arsenic and lead was described. A pilot plant was constructed to evaluate the method's commercialization potential. Flue dust was recovered by a dust collector installed to capture suspended dust generated by the smelting furnace. Arsenic content was approximately 15 per cent. Ninety per cent of the arsenic was then liquidated to lixivia and dissolved by leaching flue dust with sulphuric acid. The leaching rate decreased when flue dust had a high content of residual sulfide ore. A flotation device was then incorporated in the treatment process in order to increase the copper recovery rate. A solvent recovery process was then adopted to recover the copper and zinc contained in the solution after the arsenic recovery. An economic evaluation of the process indicated that efforts should be made to improve the efficiency of the dust treatment method. 5 refs., 6 tabs., 10 figs.

  7. Arsenic in rice: a cause for concern

    NARCIS (Netherlands)

    Hojsak, Iva; Braegger, Christian; Bronsky, Jiri; Campoy, Cristina; Colomb, Virginie; Decsi, Tamas; Domellöf, Magnus; Fewtrell, Mary; Mis, Nataša Fidler; Mihatsch, Walter; Molgaard, Christian; van Goudoever, Johannes

    2015-01-01

    Inorganic arsenic intake is likely to affect long-term health. High concentrations are found in some rice-based foods and drinks widely used in infants and young children. In order to reduce exposure, we recommend avoidance of rice drinks for infants and young children. For all of the rice products,

  8. ARSENIC REMOVAL BY IRON REMOVAL PROCESSES

    Science.gov (United States)

    Presentation will discuss the removal of arsenic from drinking water using iron removal processes that include oxidation/filtration and the manganese greensand processes. Presentation includes results of U.S. EPA field studies conducted in Michigan and Ohio on existing iron remo...

  9. Root transcripts associated with arsenic accumulation in ...

    Indian Academy of Sciences (India)

    Rasika M Potdukhe

    2018-02-06

    Feb 6, 2018 ... RNA was used to enrich mRNA and cDNA library construc- .... Discussion. Arsenic is ubiquitous in the earth's crust in the form of arsenopyrite (Zhao et al. 2010). Atmospheric flux of As is due to volcanic action, erosion of rocks and forest fires, ..... Wang H, Wong MH, Lan C, Baker AJM, Qin Y, Chen G, et al.

  10. Candesartan ameliorates arsenic-induced hypertensive vascular remodeling by regularizing angiotensin II and TGF-beta signaling in rats.

    Science.gov (United States)

    Khuman, Maibam Wanta; Harikumar, Sankaran Kutty; Sadam, Abdul; Kesavan, Manickam; Susanth, Vattaparambil Sukumaran; Parida, Subhashree; Singh, Karam Pal; Sarkar, Souvendra Nath

    2016-12-30

    Arsenic exposure can cause several cardiovascular diseases, including hypertension, atherosclerosis and microvascular disease. Earlier, we reported that arsenic-mediated enhancement of angiotensin II (AngII) signaling can impair vascular physiology. Here, we investigated whether the AT1 receptor (AT1R) blocker candesartan can ameliorate the arsenic-induced hypertensive vascular remodeling in rats and whether the amelioration could relate to attenuation in vascular AngII and TGF-β signaling. Rats were exposed to sodium arsenite (50ppm) through drinking water for 90 consecutive days. Candesartan (1mg/kg bw, orally) was administered once daily during the last 30days of arsenic exposure. Non-invasive blood pressure was recorded weekly in conscious rats, while AngII-induced change in mean arterial pressure in anaesthetized rats was measured by invasive method on the 91st day. On this day, blood was collected from other animals for measuring AngII level. Western blot of AT1, AT2 and TβRII receptors; ELISA of PTK, RasGAP, ERK-1/2, TGF-β and CTGF; immunohistochemistry of phosphorylated Smad3, Smad4 and collagen III, hydroxyproline/total collagen estimation, collagen deposition by Masson's trichrome staining and histomorphometry were carried out in thoracic aorta. Arsenic increased non-invasive systolic, diastolic and mean arterial pressure. Further, AngII caused concentration-dependent incremental change in mean arterial pressure in the arsenic-exposed rats. Arsenic upregulated AT1 and TβRII receptor proteins; elevated the levels of PTK, ERK-1/2, TGF-β and CTGF, decreased RasGAP level and augmented the immunoreactivities of Smad3, Smad4 and collagen III. Arsenic also increased hydroxyproline/total collagen level, proliferation of collagen fibres and thickness of aortic wall and collagenous adventitia. Candesartan normalized blood pressure, regularized receptor expressions, MAP kinase and TGF-β signaling, restored collagen deposition and regressed aortic thickness

  11. Arsenic Exposure in Pregnancy: A Population-based Study in Matlab, Bangladesh

    National Research Council Canada - National Science Library

    Marie E. Vahter; Li Li; Barbro Nermell; Anisur Rahman; Shams El Arifeen; Mahfuzar Rahman; Lars Åke Persson; Eva-Charlotte Ekström

    2006-01-01

    This study assessed the exposure of pregnant women to arsenic in Matlab, Bangladesh, an area with highly-elevated concentrations of arsenic in tubewells, by measuring concentrations of arsenic in urine...

  12. Metabolism and toxicity of arsenicals in mammals.

    Science.gov (United States)

    Sattar, Adeel; Xie, Shuyu; Hafeez, Mian Abdul; Wang, Xu; Hussain, Hafiz Iftikhar; Iqbal, Zahid; Pan, Yuanhu; Iqbal, Mujahid; Shabbir, Muhammad Abubakr; Yuan, Zonghui

    2016-12-01

    Arsenic (As) is a metalloid usually found in organic and inorganic forms with different oxidation states, while inorganic form (arsenite As-III and arsenate As-v) is considered to be more hazardous as compared to organic form (methylarsonate and dimethylarsinate), with mild or no toxicity in mammals. Due to an increasing trend to using arsenicals as growth promoters or for treatment purposes, the understanding of metabolism and toxicity of As gets vital importance. Its toxicity is mainly depends on oxi-reduction states (As-III or As-v) and the level of methylation during the metabolism process. Currently, the exact metabolic pathways of As have yet to be confirmed in humans and food producing animals. Oxidative methylation and glutathione conjugation is believed to be major pathways of As metabolism. Oxidative methylation is based on conversion of Arsenite in to mono-methylarsonic acid and di-methylarsenic acid in mammals. It has been confirmed that As is only methylated in the presence of glutathione or thiol compounds, suggesting that As is being methylated in trivalent states. Subsequently, non-conjugated trivalent arsenicals are highly reactive with thiol which converts the trivalent arsenicals in to less toxic pentavalent forms. The glutathione conjugate stability of As is the most important factor for determining the toxicity. It can lead to DNA damage by alerting enzyme profile and production of reactive oxygen and nitrogen species which causes the oxidative stress. Moreover, As causes immune-dysfunction by hindering cellular and humeral immune response. The present review discussed different metabolic pathways and toxic outcomes of arsenicals in mammals which will be helpful in health risk assessment and its impact on biological world. Copyright © 2016. Published by Elsevier B.V.

  13. 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.

  14. Total arsenic accumulation in yabbies (Cherax destructor Clark) exposed to elevated arsenic levels in Victorian gold mining areas, Australia.

    Science.gov (United States)

    Williams, Gemma; West, Jan M; Snow, Elizabeth T

    2008-06-01

    Arsenic is a proven carcinogen often found at high concentrations in association with gold and other heavy metals. The freshwater yabby, Cherax destructor Clark (Decapoda, Parastacidae), is a ubiquitous species native to Australia's central and eastern regions, with a growing international commercial market. However, in this region of Australia, yabby farmers often harvest organisms from old mine tailings dams with elevated environmental arsenic levels. Yabbies exposed to elevated environmental arsenic were found to accumulate and store as much as 100 microg/g arsenic in their tissues. The accumulation is proportional to the concentration of arsenic in the sediment and is high enough to be of concern for people who eat the yabbies. A comparison of arsenic levels in wild and lab-fed animals also was performed. Although there was no significant difference in the level of arsenic in the various organs of the wild animals, the animals purchased from a yabby farm showed a significantly higher arsenic concentration in their hepatopancreas (3.7 +/- 0.9 microg/g) compared to other organs (0.6-1.8 microg/g). Furthermore, after a 40-d exposure to food containing 200 to 300 microg/g inorganic arsenic, arsenate (As[V])-exposed animals showed a significant increase in tissue-specific arsenic accumulation, whereas arsenite (As[III])-exposed animals showed a lower, nonsignificant increase in As uptake, primarily in the hepatopancreas. These results have important implications for yabby growers and consumers alike.

  15. Determining the solid phases hosting arsenic in Mekong Delta sediments

    Science.gov (United States)

    Wucher, M.; Stuckey, J. W.; McCurdy, S.; Fendorf, S.

    2011-12-01

    The major river systems originating from the Himalaya deposit arsenic bearing sediment into the deltas of South and Southeast Asia. High rates of sediment and organic carbon deposition combined with frequent flooding leads to anaerobic processes that release arsenic into the pore-water. Arsenic concentrations in the groundwater of these sedimentary basins are often above the World Health Organization drinking water standard of 10 μg As L-1. As a result, 150 million people are at risk of chronic arsenic poisoning through water and rice consumption. The composition of the iron bearing phases hosting the arsenic in these deltaic sediments is poorly understood. Here we implemented a suite of selective chemical extractions to help constrain the types of arsenic bearing solid phases, which were complimented with synchrotron-based X-ray absorption spectroscopy and X-ray diffraction analyses to define the arsenic and iron mineralogy of the system. Sediment cores were collected in triplicate from a seasonally-inundated wetland in Cambodia at depths of 10, 50, 100, and 150 centimeters. We hypothesize that (i) arsenic will be predominantly associated with iron oxides, and (ii) the ratio of crystalline to amorphous iron oxides will increase with sediment depth (and age). We performed four selective extractions in parallel to quantify the various pools of arsenic. First, 1 M MgCl2 was used to extract electrostatically-bound arsenic (labile forms) from the sediment. Second, 1 M NaH2PO4 targeted strongly adsorbed arsenic. Third, 1 M HCl was used to liberated arsenic coprecipitated with amorphous Fe/Mn oxides, carbonates, and acid-volatile sulfides. Finally, a dithionite extraction was used to account for arsenic associated with reducible Fe/Mn oxides. Through this work, we identified the composition of the phases hosting arsenic at various depths through the soil profile, improving our understanding of how arsenic persists in the aquifer. In addition, defining the arsenic and

  16. 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.

  17. Total and inorganic arsenic in fish samples from Norwegian waters

    DEFF Research Database (Denmark)

    Julshamn, K.; Nilsen, B. M.; Frantzen, S.

    2012-01-01

    The contents of total arsenic and inorganic arsenic were determined in fillet samples of Northeast Arctic 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 (...

  18. Adsorption of arsenic from aqueous solution using magnetic graphene oxide

    Science.gov (United States)

    Sherlala, A. I. A.; Raman, A. A.; Bello, M. M.

    2017-06-01

    A binary of graphene oxide (GO) and iron oxide (IO) was prepared and used for the removal of arsenic from aqueous solution. The synthesized compound was characterized using XRD analysis. The prepared composite was used for the adsorption of arsenic from aqueous solution. Central Composite Design was used to design the adsorption experiments and to investigate the effects of operational parameters (initial concentration of arsenic, adsorbent dosage, pH and time) on the adsorption capacity and efficiency. The adsorbent shows a high adsorption capacity for the arsenic. The adsorption efficiency ranges between 33.2 % and 99.95 %. The most significant factors affecting the adsorption capacity were found to be the initial concentration of arsenic and the adsorbent dosage. The initial pH of the solution slightly affects the adsorption capacity, with the maximum adsorption capacity occurring around pH 6 - 7. Thus, the developed adsorbent has a potential for effective removal of arsenic from aqueous solution.

  19. 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.

  20. Arsenic and skin cancer – Case report with chemoprevention

    OpenAIRE

    Uwe Wollina

    2016-01-01

    ABSTRACT Introduction: Arsenic is a potentially hazardous metalloid that can cause skin cancer. We want to demonstrate a case of chronic arsenicosis and the potential of chemoprevention with retinoids. Case Report: This is a case report of a 72-year-old male patient who was exposed to arsenics by dust and direct skin contact over 3 years in a chemical plant in the late fourties. He developed multiple arsenic keratosis clincialll resembling actinic keratoses, Bowen’s disease and palmar...

  1. Groundwater arsenic contamination in one of the 107 arsenic-affected blocks in West Bengal, India: Status, distribution, health effects and factors responsible for arsenic poisoning.

    Science.gov (United States)

    Roychowdhury, Tarit

    2010-11-01

    A somewhat detailed study was carried out in Gaighata, one of the 107 arsenic-affected blocks in West Bengal, India, to determine the degree of groundwater contamination with arsenic, its depth wise distribution, correlation with iron, arsenical health effects to the inhabitants and the factors responsible for arsenic poisoning. Groundwater in all the 107 mouzas over 13 gram-panchayets in Gaighata block contains arsenic above 0.01mgl(-1) and in 91 mouzas, arsenic concentration has been found above 0.05mgl(-1). About 59.2 and 40.3% of the tubewell water samples contain arsenic above 0.01 and 0.05mgl(-1), respectively. The approximate population drinking arsenic-contaminated water above 0.01 and 0.05mgl(-1) are 106,560 and 72,540, respectively. The tubewells that were installed within the depth range of 15.4-30.3m are mostly arsenic-contaminated. Even the shallow groundwater level (7.87-15.1m) is arsenic-contaminated. Both arsenic and iron concentrations in groundwater gradually increase from lower depth to higher depth up to 39.4m, and then decrease with increasing depth. About 58% of the deep tubewell water samples (depth range 122-182m, n=31) contain arsenic ≥0.05mgl(-1). About 72% of the arsenic-contaminated deep tubewells (n=18) were safe when surveyed first time. But within a span of 2-5 years, they became contaminated with arsenic. The linear regression shows direct correlation between arsenic and iron concentrations in groundwater (r(2)=0.8114, parsenic from water by an adult male and female in the surveyed areas are 11.7 and 13.1μg/kg body wt./day, respectively and these values are higher than the WHO recommended PTDI value of inorganic arsenic (2.1μg/kg body wt./day). Mean arsenic concentrations in urine, hair and nail samples, collected from the inhabitants of Gutri mouza are higher than their normal level and the values are 292μgl(-1) (range: 8.35-1024μg l(-1), n=193), 2.50mgkg(-1) (range: 0.17-5.99mgkg(-1), n=132), and 6.05mgkg(-1) (range: 0

  2. A laboratory test of NOM-assisted remediation of arsenic and copper contaminated soils

    DEFF Research Database (Denmark)

    Rasmussen, Signe Bonde; Jensen, Julie Katrine; Borggaard, Ole K.

    2015-01-01

    Soils contaminated by arsenic (As) and copper (Cu) must be remediated because As and Cu are non-degradable and toxic. On moderately contaminated soils, As and Cu may be removed by in-situ plant uptake (phytoremediation), whereas strongly contaminated soils must be removed and cleaned by soil...... at neutral pH to enhance in-situ phytoremediation of moderately contaminated soils. Citrate (and NTA) cannot be suggested for enhancement of on-site phytoremediation because of high mobilization rates caused by these extractants, which through leaching and runoff may lead to contamination of recipient waters...

  3. Well Water Arsenic Exposure, Arsenic Induced Skin-Lesions and Self-Reported Morbidity in Inner Mongolia

    Directory of Open Access Journals (Sweden)

    Yajuan Xia

    2009-03-01

    Full Text Available Residents of the Bayingnormen region of Inner Mongolia have been exposed to arsenic-contaminated well water for over 20 years, but relatively few studies have investigated health effects in this region. We surveyed one village to document exposure to arsenic and assess the prevalence of arsenic-associated skin lesions and self-reported morbidity. Five-percent (632 of the 12,334 residents surveyed had skin lesions characteristics of arsenic exposure. Skin lesions were strongly associated with well water arsenic and there was an elevated prevalence among residents with water arsenic exposures as low as 5 μg/L-10 μg/L. The presence of skin lesions was also associated with self-reported cardiovascular disease.

  4. 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.

  5. Pattern of skin bacteria in palmar arsenical keratosis

    Directory of Open Access Journals (Sweden)

    Nadia Bintha Khalil

    2016-12-01

    Full Text Available The aim of the present study was to examine the involvement of skin bacteria in the pathogenesis of keratosis. Skin swab of five different sites (palm, dorsum of the hand, chest, axilla and alar crease from arsenic unexposed volunteer (n = 15, arsenic exposed (n = 15 and arsenicosis patients (n= 20 were collected for bacterial culture. The skin of arsenic unexposed volunteers contained Staphylococcus epidermidis and Bacillus spp. Chronic exposure to high concentration of arsenic through drinking water altered the skin bacterial pattern. The growth of Pseudomonas spp. increased in different sites of the skin. But in patient of arsenicosis, the skin of the palm shows the growth of Enterobacter spp.

  6. 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.

  7. Role of Folic Acid on Symptoms of Chronic Arsenic Toxicity

    Science.gov (United States)

    Ghose, Nelima; Majumdar, Kunal Kanti; Ghose, A. K.; Saha, C. K.; Nandy, A. K.; Mazumder, D. N. Guha

    2014-01-01

    Background: Chronic arsenic toxicity (Arsenicosis) due to drinking of arsenic contaminated ground water is a global problem. However, its treatment is unsatisfactory. Methylation of arsenic facilitates its urinary excretion. Persons with relatively lower proportion of urinary dimethyl arsenic acid (DMA) are found to have at greater risk of developing symptoms of arsenicosis including its complications. The biochemical pathway responsible for methylation of arsenic is a folate-dependent pathway. Studies in rodents and humans suggest that folate nutritional status influences the metabolism of arsenic. Methods: The present study compares the effect of giving folic acid on 32 arsenicosis patients during a 6-month period and comparing the results with clinical effect of taking only arsenic-free safe water on 45 age and sex-matched arsenic-affected people for the same period. Results: There was significant improvement of arsenical skin lesion score of both patients treated with folic acid (2.96 ± 1.46 to 1.90 ± 0.90, P arsenicosis cases could help in reducing clinical symptoms of arsenicosis. PMID:24554997

  8. Arsenic contamination in food chain: Thread to global food security

    Science.gov (United States)

    Kashyap, C. A.

    2016-12-01

    The supply of good quality food is a necessity for economic and social health 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.

  9. GLI3 Links Environmental Arsenic Exposure and Human Fetal Growth

    Directory of Open Access Journals (Sweden)

    Emily F. Winterbottom

    2015-06-01

    Full Text Available Although considerable evidence suggests that in utero arsenic exposure affects children's health, these data are mainly from areas of the world where groundwater arsenic levels far exceed the World Health Organization limit of 10 μg/L. We, and others, have found that more common levels of in utero arsenic exposure may also impact children's health. However, the underlying molecular mechanisms are poorly understood. To address this issue, we analyzed the expression of key developmental genes in fetal placenta in a birth cohort of women using unregulated water supplies in a US region with elevated groundwater arsenic. We identified several genes whose expression associated with maternal arsenic exposure in a fetal sex-specific manner. In particular, expression of the HEDGEHOG pathway component, GLI3, in female placentae was both negatively associated with arsenic exposure and positively associated with infant birth weight. This suggests that modulation of GLI3 in the fetal placenta, and perhaps in other fetal tissues, contributes to arsenic's detrimental effects on fetal growth. We showed previously that arsenic-exposed NIH3T3 cells have reduced GLI3 repressor protein. Together, these studies identify GLI3 as a key signaling node that is affected by arsenic, mediating a subset of its effects on developmental signaling and fetal health.

  10. 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

  11. Assessment of arsenic exposure by measurement of urinary speciated inorganic arsenic metabolites in workers in a semiconductor manufacturing plant.

    Science.gov (United States)

    Byun, Kiwhan; Won, Yong Lim; Hwang, Yang In; Koh, Dong-Hee; Im, Hosub; Kim, Eun-A

    2013-10-11

    The purpose of this study was to evaluate the exposure to arsenic in preventive maintenance (PM) engineers in a semiconductor industry by detecting speciated inorganic arsenic metabolites in the urine. The exposed group included 8 PM engineers from the clean process area and 13 PM engineers from the ion implantation process area; the non-exposed group consisted of 14 office workers from another company who were not occupationally exposed to arsenic. A spot urine specimen was collected from each participant for the detection and measurement of speciated inorganic arsenic metabolites. Metabolites were separated by high performance liquid chromatography-inductively coupled plasma spectrometry-mass spectrometry. Urinary arsenic metabolite concentrations were 1.73 g/L, 0.76 g/L, 3.45 g/L, 43.65 g/L, and 51.32 g/L for trivalent arsenic (As3+), pentavalent arsenic (As5+), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and total inorganic arsenic metabolites (As3+ + As5+ + MMA + DMA), respectively, in clean process PM engineers. In ion implantation process PM engineers, the concentrations were 1.74 g/L, 0.39 g/L, 3.08 g/L, 23.17 g/L, 28.92 g/L for As3+, As5+, MMA, DMA, and total inorganic arsenic metabolites, respectively. Levels of urinary As3+, As5+, MMA, and total inorganic arsenic metabolites in clean process PM engineers were significantly higher than that in the non-exposed group. Urinary As3+ and As5+ levels in ion implantation process PM engineers were significantly higher than that in non-exposed group. Levels of urinary arsenic metabolites in PM engineers from the clean process and ion implantation process areas were higher than that in office workers. For a complete assessment of arsenic exposure in the semiconductor industry, further studies are needed.

  12. Arsenic release during managed aquifer recharge (MAR)

    Science.gov (United States)

    Pichler, T.; Lazareva, O.; Druschel, G.

    2013-12-01

    The mobilization and addition of geogenic trace metals to groundwater is typically caused by anthropogenic perturbations of the physicochemical conditions in the aquifer. This can add dangerously high levels of toxins to groundwater, thus compromising its use as a source of drinking water. In several regions world-wide, aquifer storage and recovery (ASR), a form of managed aquifer recharge (MAR), faces the problem of arsenic release due to the injection of oxygenated storage water. To better understand this process we coupled geochemical reactive transport modeling to bench-scale leaching experiments to investigate and verify the mobilization of geogenic arsenic (As) under a range of redox conditions from an arsenic-rich pyrite bearing limestone aquifer in Central Florida. Modeling and experimental observations showed similar results and confirmed the following: (1) native groundwater and aquifer matrix, including pyrite, were in chemical equilibrium, thus preventing the release of As due to pyrite dissolution under ambient conditions; (2) mixing of oxygen-rich surface water with oxygen-depleted native groundwater changed the redox conditions and promoted the dissolution of pyrite, and (3) the behavior of As along a flow path was controlled by a complex series of interconnected reactions. This included the oxidative dissolution of pyrite and simultaneous sorption of As onto neo-formed hydrous ferric oxides (HFO), followed by the reductive dissolution of HFO and secondary release of adsorbed As under reducing conditions. Arsenic contamination of drinking water in these systems is thus controlled by the re-equilibration of the system to more reducing conditions rather than a purely oxidative process.

  13. Human Arsenic Poisoning Issues in Central-East Indian Locations: Biomarkers and Biochemical Monitoring

    Directory of Open Access Journals (Sweden)

    Madhurima Pandey

    2007-03-01

    Full Text Available The study reports the use of three biomarkers i.e. total arsenic in hair and nails, total arsenic in blood, and total arsenic in urine to identify or quantify arsenic exposure and concomitant health effects. The main source of arsenic was inorganic exposure through drinking water. The arsenic levels and the health effects were analyzed closely in a family having maximum symptoms of arsenic. Based on the result of this study it is reported that there exist a correlation between the clinically observable symptoms, the blood and urine arsenic level, and the arsenic intake through drinking water. An intensive study on the urinary arsenic levels was carried out in which the urine levels of arsenic and the urine sufficiency tests were performed. A composite picture of body burden of arsenic has been obtained by carrying out a complete biochemical analysis of a maximum affected family. This confirms pronounced chronic exposure of the arsenic to these people. A combined correlation study on the arsenic levels measured in whole blood, urine, hair, nails and age present a remarkable outcome. Accordingly, the arsenic levels in blood are negatively correlated with the urine arsenic levels, which indicate either the inadequacy of the renal system in cleaning the blood arsenic or a continuous recirculation of the accumulated arsenic. This is an important conclusion about arsenical metabolism in humans. The study also raises the issues of the prospects of complete elimination of the accumulated arsenic and the reversibility of the health effects. Based on the work in Kourikasa village we report that there are very remote chances of complete purging of arsenic and thus reversibility of the health effects owing to various factors. The paper also discusses the various issues concerning the chronic arsenic poisoning management in the affected locations.

  14. 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.

  15. 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

  16. Arsenic metabolites in humans after ingestion of wakame seaweed

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    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.

  17. Arsenic Accumulation in Rice and Probable Mitigation Approaches: A Review

    Directory of Open Access Journals (Sweden)

    Anindita Mitra

    2017-10-01

    Full Text Available According to recent reports, millions of people across the globe are suffering from arsenic (As toxicity. Arsenic is present in different oxidative states in the environment and enters in the food chain through soil and water. In the agricultural field, irrigation with arsenic contaminated water, that is, having a higher level of arsenic contamination on the top soil, which may affects the quality of crop production. The major crop like rice (Oryza sativa L. requires a considerable amount of water to complete its lifecycle. Rice plants potentially accumulate arsenic, particularly inorganic arsenic (iAs from the field, in different body parts including grains. Different transporters have been reported in assisting the accumulation of arsenic in plant cells; for example, arsenate (AsV is absorbed with the help of phosphate transporters, and arsenite (AsIII through nodulin 26-like intrinsic protein (NIP by the silicon transport pathway and plasma membrane intrinsic protein aquaporins. Researchers and practitioners are trying their level best to mitigate the problem of As contamination in rice. However, the solution strategies vary considerably with various factors, such as cultural practices, soil, water, and environmental/economic conditions, etc. The contemporary work on rice to explain arsenic uptake, transport, and metabolism processes at rhizosphere, may help to formulate better plans. Common agronomical practices like rain water harvesting for crop irrigation, use of natural components that help in arsenic methylation, and biotechnological approaches may explore how to reduce arsenic uptake by food crops. This review will encompass the research advances and practical agronomic strategies on arsenic contamination in rice crop.

  18. Arsenic Mobilization Through Microbial Bioreduction of Ferrihydrite Nanoparticles

    Science.gov (United States)

    Tadanier, C. J.; Roller, J.; Schreiber, M. E.

    2004-12-01

    Under anaerobic conditions Fe(III)-reducing microorganisms can couple the reduction of solid phase Fe(III) (hydr)oxides with the oxidation of organic carbon. Nutrients and trace metals, such as arsenic, associated with Fe(III) hydroxides may be mobilized through microbially-mediated surface reduction. Although arsenic mobilization has been attributed to mineral surface reduction in a variety of pristine and contaminated environments, minimal information exists on the mechanisms causing this arsenic mobilization. Understanding of the fundamental biochemical and physicochemical processes involved in these mobilization mechanisms is still limited, and has been complicated by the often contradictory and interchangeable terminology used in the literature to describe them. We studied arsenic mobilization mechanisms using a series of controlled microcosm experiments containing aggregated arsenic-bearing ferrihydrite nanoparticles and an Fe(III)-reducing microorganism, Geobacter metallireducens. The phase distribution of iron and arsenic was determined through filtration and ultracentrifugation techniques. Experimental results showed that in the biotic trials, approximately 10 percent of the Fe(III) was reduced to Fe(II) by microbial activity, which remained associated with ferrihydrite surfaces. Biotic activity resulted in changes in nanoparticle surface potential and caused deflocculation of nanoparticle aggregates. Deflocculated nanoparticles were able to pass through a 0.2 micron filter and could only be removed from solution by ultracentrifugation. Arsenic mobilized over time in the biotic trials was found to be exclusively associated with the nanoparticles; 98 percent of arsenic that passed through a 0.2 micron filter was removed from solution by ultracentrifugation. None of these changes were observed in abiotic controls. Because arsenic contamination of natural waters due to mobilization from mineral surfaces is a significant route of human arsenic exposure

  19. Chronic arsenic toxicity: Studies in West Bengal, India

    Directory of Open Access Journals (Sweden)

    Debendranath Guha Mazumder

    2011-09-01

    Full Text Available Chronic arsenic toxicity (arsenicosis as a result of drinking arsenic-contaminated groundwater is a major environmental health hazard throughout the world, including India. A lot of research on health effects, including genotoxic effect of chronic arsenic toxicity in humans, have been carried out in West Bengal during the last 2 decades. A review of literature including information available from West Bengal has been made to characterize the problem. Scientific journals, monographs, and proceedings of conferences with regard to human health effects, including genotoxicity, of chronic arsenic toxicity have been reviewed. Pigmentation and keratosis are the specific skin diseases characteristic of chronic arsenic toxicity. However, in West Bengal, it was found to produce various systemic manifestations, such as chronic lung disease, characterized by chronic bronchitis, chronic obstructive and/or restrictive pulmonary disease, and bronchiectasis; liver diseases, such as non cirrhotic portal fibrosis; polyneuropathy; peripheral vascular disease; hypertension; nonpitting edema of feet/hands; conjunctival congestion; weakness; and anemia. High concentrations of arsenic, greater than or equal to 200 μg/L, during pregnancy were found to be associated with a sixfold increased risk for stillbirth. Cancers of skin, lung, and urinary bladder are the important cancers associated with this toxicity. Of the various genotoxic effects of arsenic in humans, chromosomal aberration and increased frequency of micronuclei in different cell types have been found to be significant. Various probable mechanisms have been incriminated to cause DNA damage because of chronic arsenic toxicity. The results of the study in West Bengal suggest that deficiency in DNA repair capacity, perturbation of methylation of promoter region of p53 and p16 genes, and genomic methylation alteration may be involved in arsenic-induced disease manifestation in humans. P53 polymorphism has been

  20. Arsenic speciation of geothermal waters in New Zealand.

    Science.gov (United States)

    Lord, Gillian; Kim, Nick; Ward, Neil I

    2012-12-01

    Total arsenic and four arsenic species; arsenite (iAs(III)), arsenate (iAs(V)), dimethylarsinic acid (DMA(V)) and monomethylarsonic acid (MA(V)), are reported in 28 geothermal features from the Taupo Volcanic Zone (TVZ) and Waikato region of New Zealand. Samples were collected for arsenic speciation analysis via a solid phase extraction (SPE) kit allowing the separation, stabilisation and pre-concentration of the species at the time of sample collection in the field. This is the first research to present data for arsenic species collected by this technique in geothermal waters from New Zealand. Total arsenic concentrations, determined by inductively coupled plasma mass spectrometry (ICP-MS), ranged from 0.008 to 9.08 mg l⁻¹ As. The highest levels were discovered in three features in Tokaanu (Taumatapuhipuhi, Takarea #5 and #6), with arsenic concentrations of 8.59, 8.70 and 9.08 mg l⁻¹ As, respectively. Inorganic arsenic species were predominant in the geothermal waters, with arsenite contributing to more than 70% of the total arsenic in the majority of samples. Organic species were also determined in all samples, indicating the presence of microbial activity. A potential risk to human health was highlighted due to the high levels of arsenic, mainly as arsenite, in geothermal features linked to bathing pools. Further research is needed into dermal absorption as a potential route of arsenic exposure whilst bathing in these hot pools, as it may contribute to an occurrence of acute arsenic-related health problems.

  1. Genes involved in arsenic transformation and resistance associated with different levels of arsenic-contaminated soils

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    Wang Gejiao

    2009-01-01

    Full Text Available Abstract Background Arsenic is known as a toxic metalloid, which primarily exists in inorganic form [As(III and As(V] and can be transformed by microbial redox processes in the natural environment. As(III is much more toxic and mobile than As(V, hence microbial arsenic redox transformation has a major impact on arsenic toxicity and mobility which can greatly influence the human health. Our main purpose was to investigate the distribution and diversity of microbial arsenite-resistant species in three different arsenic-contaminated soils, and further study the As(III resistance levels and related functional genes of these species. Results A total of 58 arsenite-resistant bacteria were identified from soils with three different arsenic-contaminated levels. Highly arsenite-resistant bacteria (MIC > 20 mM were only isolated from the highly arsenic-contaminated site and belonged to Acinetobacter, Agrobacterium, Arthrobacter, Comamonas, Rhodococcus, Stenotrophomonas and Pseudomonas. Five arsenite-oxidizing bacteria that belonged to Achromobacter, Agrobacterium and Pseudomonas were identified and displayed a higher average arsenite resistance level than the non-arsenite oxidizers. 5 aoxB genes encoding arsenite oxidase and 51 arsenite transporter genes [18 arsB, 12 ACR3(1 and 21 ACR3(2] were successfully amplified from these strains using PCR with degenerate primers. The aoxB genes were specific for the arsenite-oxidizing bacteria. Strains containing both an arsenite oxidase gene (aoxB and an arsenite transporter gene (ACR3 or arsB displayed a higher average arsenite resistance level than those possessing an arsenite transporter gene only. Horizontal transfer of ACR3(2 and arsB appeared to have occurred in strains that were primarily isolated from the highly arsenic-contaminated soil. Conclusion Soils with long-term arsenic contamination may result in the evolution of highly diverse arsenite-resistant bacteria and such diversity was probably caused in

  2. Arsenic speciation in arsenic-rich Brazilian soils from gold mining sites under anaerobic incubation.

    Science.gov (United States)

    de Mello, Jaime W V; Talbott, Jonathan L; Scott, John; Roy, William R; Stucki, Joseph W

    2007-09-01

    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. 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. 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. 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. In general, As(V) and organic As were the dominant species in solution, which is surprising under anaerobic conditions in terrestrial environments

  3. Adsorption and desorption of arsenic to aquifer sediment on the Red River floodplain at Nam Du, Vietnam

    Science.gov (United States)

    Thi Hoa Mai, Nguyen; Postma, Dieke; Thi Kim Trang, Pham; Jessen, Søren; Hung Viet, Pham; Larsen, Flemming

    2014-10-01

    The adsorption of arsenic onto aquifer sediment from the Red River floodplain, Vietnam, was determined in a series of batch experiments. Due to water supply pumping, river water infiltrates into the aquifer at the field site and has leached the uppermost aquifer sediments. The leached sediments remain anoxic but contain little reactive arsenic and iron, and are used in our experiments. The adsorption and desorption experiments were carried out by addition or removal of arsenic from the aqueous phase in sediment suspensions under strictly anoxic conditions. Also the effects of HCO3, Fe(II), PO4 and Si on arsenic adsorption were explored. The results show much stronger adsorption of As(V) as compared to As(III), full reversibility for As(III) adsorption and less so for As(V). The presence or absence of HCO3 did not influence arsenic adsorption. Fe(II) enhanced As(V) sorption but did not influence the adsorption of As(III) in any way. During simultaneous adsorption of As(III) and Fe(II), As(III) was found to be fully desorbable while Fe(II) was completely irreversibly adsorbed and clearly the two sorption processes are uncoupled. Phosphate was the only solute that significantly could displace As(III) from the sediment surface. Compiling literature data on arsenic adsorption to aquifer sediment in Vietnam and Bangladesh revealed As(III) isotherms to be almost identical regardless of the nature of the sediment or the site of sampling. In contrast, there was a large variation in As(V) adsorption isotherms between studies. A tentative conclusion is that As(III) and As(V) are not adsorbing onto the same sediment surface sites. The adsorption behavior of arsenic onto aquifer sediments and synthetic Fe-oxides is compared. Particularly, the much stronger adsorption of As(V) than of As(III) onto Red River as well as on most Bangladesh aquifer sediments, indicates that the perception that arsenic, phosphate and other species compete for the same surface sites of iron oxides in

  4. Chronic occupational exposure to arsenic induces carcinogenic gene signaling networks and neoplastic transformation in human lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Stueckle, Todd A., E-mail: tstueckle@hsc.wvu.edu [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States); Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505 (United States); Lu, Yongju, E-mail: yongju6@hotmail.com [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States); Davis, Mary E., E-mail: mdavis@wvu.edu [Department of Physiology, West Virginia University, Morgantown, WV 26506 (United States); Wang, Liying, E-mail: lmw6@cdc.gov [Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505 (United States); Jiang, Bing-Hua, E-mail: bhjiang@jefferson.edu [Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Holaskova, Ida, E-mail: iholaskova@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Schafer, Rosana, E-mail: rschafer@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Barnett, John B., E-mail: jbarnett@hsc.wvu.edu [Department of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, WV 26506 (United States); Rojanasakul, Yon, E-mail: yrojan@hsc.wvu.edu [Department of Basic Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506 (United States)

    2012-06-01

    Chronic arsenic exposure remains a human health risk; however a clear mode of action to understand gene signaling-driven arsenic carcinogenesis is currently lacking. This study chronically exposed human lung epithelial BEAS-2B cells to low-dose arsenic trioxide to elucidate cancer promoting gene signaling networks associated with arsenic-transformed (B-As) cells. Following a 6 month exposure, exposed cells were assessed for enhanced cell proliferation, colony formation, invasion ability and in vivo tumor formation compared to control cell lines. Collected mRNA was subjected to whole genome expression microarray profiling followed by in silico Ingenuity Pathway Analysis (IPA) to identify lung carcinogenesis modes of action. B-As cells displayed significant increases in proliferation, colony formation and invasion ability compared to BEAS-2B cells. B-As injections into nude mice resulted in development of primary and secondary metastatic tumors. Arsenic exposure resulted in widespread up-regulation of genes associated with mitochondrial metabolism and increased reactive oxygen species protection suggesting mitochondrial dysfunction. Carcinogenic initiation via reactive oxygen species and epigenetic mechanisms was further supported by altered DNA repair, histone, and ROS-sensitive signaling. NF-κB, MAPK and NCOR1 signaling disrupted PPARα/δ-mediated lipid homeostasis. A ‘pro-cancer’ gene signaling network identified increased survival, proliferation, inflammation, metabolism, anti-apoptosis and mobility signaling. IPA-ranked signaling networks identified altered p21, EF1α, Akt, MAPK, and NF-κB signaling networks promoting genetic disorder, altered cell cycle, cancer and changes in nucleic acid and energy metabolism. In conclusion, transformed B-As cells with their whole genome expression profile provide an in vitro arsenic model for future lung cancer signaling research and data for chronic arsenic exposure risk assessment. Highlights: ► Chronic As{sub 2}O

  5. Uptake kinetics of arsenic by lettuce cultivars under hydroponics ...

    African Journals Online (AJOL)

    Arsenic (As) uptake ability based on kinetic parameters by two lettuce cultivars; Sijibaiye (SJBY) and Texuanyanlingsun (TXYLS) was investigated in nutrient solution containing eight levels of arsenic (As). Depletion of As from solution was monitored over a period of 24 h at regular time to estimate As uptake kinetics of the ...

  6. In vitro toxicological characterisation of three arsenic-containing hydrocarbons.

    Science.gov (United States)

    Meyer, S; Matissek, M; Müller, S M; Taleshi, M S; Ebert, F; Francesconi, K A; Schwerdtle, T

    2014-05-01

    Arsenic-containing hydrocarbons are one group of fat-soluble organic arsenic compounds (arsenolipids) found in marine fish and other seafood. A risk assessment of arsenolipids is urgently needed, but has not been possible because of the total lack of toxicological data. In this study the cellular toxicity of three arsenic-containing hydrocarbons was investigated in cultured human bladder (UROtsa) and liver (HepG2) cells. Cytotoxicity of the arsenic-containing hydrocarbons was comparable to that of arsenite, which was applied as the toxic reference arsenical. A large cellular accumulation of arsenic, as measured by ICP-MS/MS, was observed after incubation of both cell lines with the arsenolipids. Moreover, the toxic mode of action shown by the three arsenic-containing hydrocarbons seemed to differ from that observed for arsenite. Evidence suggests that the high cytotoxic potential of the lipophilic arsenicals results from a decrease in the cellular energy level. This first in vitro based risk assessment cannot exclude a risk to human health related to the presence of arsenolipids in seafood, and indicates the urgent need for further toxicity studies in experimental animals to fully assess this possible risk.

  7. Experimental assessment of arsenic toxicity in garole sheep in India

    Directory of Open Access Journals (Sweden)

    Chinmoy Maji

    2016-09-01

    Full Text Available Arsenic, a dangerous bio-accumulative poison, is a grave threat affecting a large number of people as well as animals throughout the World, particularly in Bangladesh and West Bengal, India. It is also a matter of concern as continuously entering into food chain through biotic and abiotic products. The present study was conducted to evaluate the experimental effect of arsenic toxicosis on Garole sheep of West Bengal. One group was subjected to oral arsenic exposure @ 6.6 mg Kg−1 over 133 days when rests considered as negative control. Periodical arsenic estimation in wool, urine and feces along with hemato-biochemical alteration were checked thoroughly. It was evident from the study that long term arsenic exposure exerted a significant (p < 0.01 alteration compared to normal animal which were further supported by clinical abnormalities. Exposed animals showed histological changes throughout major internal organs like coagulative necrosis of liver, tubular nephritis of kidney and acanthosis of skin etc. The bio-accumulative and excretion pattern of arsenic inside body were also well understood by the arsenic estimation study of wool, urine and feces which may be helpful for discussion regarding arsenic entry into food chain via animals.

  8. Reconnaissance Survey of Arsenic Concentration in Ground-water ...

    African Journals Online (AJOL)

    . The measurements were carried out in the field using the Wagtech Arsenator field test kit (Wag-We 100500) equipment, which gives direct readout of arsenic concentration in the critical range 2-100 mg l-1. Arsenic concentrations were in the ...

  9. Isolation and screening of arsenic resistant rhizobacteria of ...

    African Journals Online (AJOL)

    Ludwigia octovalvis was characterized for its potential in arsenic phytoremediation. Epiphyte rhizobacteria from the roots of L. octovalvis were isolated in five different arsenic concentrations (4, 20, 40, 60 and 80 mg kg-1) and control after single exposure for 35 days. Results show that 109 colonies were isolated which were ...

  10. Estimation of arsenic in nail using silver diethyldithiocarbamate method

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    Habiba Akhter Bhuiyan

    2015-08-01

    Full Text Available Spectrophotometric method of arsenic estimation in nails has four steps: a washing of nails, b digestion of nails, c arsenic generation, and finally d reading absorbance using spectrophotometer. Although the method is a cheapest one, widely used and effective, it is time consuming, laborious and need caution while using four acids.

  11. Biosorption of arsenic and cadmium from aqueous solutions ...

    African Journals Online (AJOL)

    The biosorption of cadmium and arsenic from aqueous solutions onto the unmodified compact biomass of microscopic filamentous fungus Aspergillus clavatus DESM. was studied in the concentration range of 0.25 – 100 mg.l-1. The experimental biosorption results for arsenic and cadmium followed well the Freundlich ...

  12. Arsenic in Drinking Water--The Silent Killer

    Science.gov (United States)

    Wajrak, Magdalena

    2011-01-01

    Natural arsenic salts are present in all waters, with natural concentrations of less than 10 parts per billion (ppb). Unfortunately, there is an increasing number of countries where toxic arsenic compounds in groundwater, which is used for drinking and irrigation, have been detected at concentrations above the World Health Organization's…

  13. Genome sequences of Listeria monocytogenes strains with resistance to arsenic

    Science.gov (United States)

    Listeria monocytogenes frequently exhibits resistance to arsenic. We report here the draft genome sequences of eight genetically diverse arsenic-resistant L. monocytogenes strains from human listeriosis and food-associated environments. Availability of these genomes would help to elucidate the role ...

  14. Phytoremediation of arsenic by Trapa natans in a hydroponic system.

    Science.gov (United States)

    Baruah, Sangita; Borgohain, Jayasree; Sarma, K P

    2014-05-01

    Phytoremediation of arsenic (As) by water chestnut (Trapa natans) in a hydroponic system was studied. Plants were grown at two concentrations of arsenic, 1.28 mg/L and 10.80 mg/L, in a single metal solution. Scanning Electron Microscope-Energy Dispersive X-ray (SEM-EDX) confirmed highest arsenic concentration in the roots, followed by shoots and leaves. SEM-EDX also confirmed internalization of arsenic in T. natans and the damage caused due to arsenic exposure. Fourier Transform Infra Red Spectroscopy (FT-IRS) indicated that the binding characteristics of the arsenic ions involved the hydroxyl, amide, amino, and thiol groups in the biomass. Chlorophyll concentration decreased with increasing metal concentration and duration of exposure, but proline content increases with increasing concentration in the plant. Morphological changes were studied on the 3rd, 5th and 7th day. Unhealthy growth and chlorosis were found to be related with arsenic toxicity. From the above studies it is clear that T. natans can be used successfully for the removal of arsenic ions by a phytoremediation process.

  15. 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

  16. ARSENIC TREATMENT IN OHIO: CONSIDERATIONS AND CASE STUDIES

    Science.gov (United States)

    The recently promulgated Arsenic Rule will require that many new drinking water systems treat their water to remove arsenic. It has been projected that the State of Ohio will have nearly 140 community and non-community non-transient water systems in violation of the Rule. As a ...

  17. Arsenic in Ground Water of the United States

    Science.gov (United States)

    ... found in the West, the Midwest, parts of Texas, and the Northeast. See Ryker (2001) for more information. See Focazio and others (2000) for the use of available data for characterizing arsenic concentrations in public-water supply systems. See Gronberg (2011) for updated arsenic ...

  18. Determination of Arsenic Content of Available Traditional Medicines ...

    African Journals Online (AJOL)

    Arsenic (As) is one of the potential toxic heavy metals which may be present in some herbal products as it can penetrate the plant via contaminated soil and water. Both trivalent and pentavalent forms of As are rapidly absorbed from the gastrointestinal tract [10]. Arsenic (As) also has a direct toxic effect on cellular respiration ...

  19. Bioscorodite: biological crystallization of scorodite for arsenic removal

    NARCIS (Netherlands)

    Gonzalez-Contreras, P.A.

    2012-01-01

    The use of arsenic is banned for most applications, leading to its accumulation as arsenic trioxide and ferric arsenate sludge. The aim of this thesis was to develop a controlled process for biological crystallization of scorodite from metallurgical streams. In this thesis, the proof of principle,

  20. Biogenic scorodite crystallization by Acidianus sulfidivorans for arsenic removal

    NARCIS (Netherlands)

    Gonzalez-Contreras, P.A.; Weijma, J.; Weijden, van der R.D.; Buisman, C.J.N.

    2010-01-01

    Scorodite is an arsenic mineral with the chemical formula FeAsO4·2H2O. It is the most common natural arsenate associated with arsenic-bearing ore deposits. In the present study we show that the thermoacidophilic iron-oxidizing archaeon Acidianus sulfidivorans is able to precipitate scorodite in the

  1. Arsenic removal from drinking water using granular ferric hydroxide ...

    African Journals Online (AJOL)

    In continuous column tests (five cycles) with tap water using GFH, consistently less than 5 mg/l of arsenic was achieved in the finished water for 38 to 42 hours of column operation, where the influent had a spiked arsenic concentration of 500 mg/l. High bed volumes (1260 and 1140) up to a breakthrough concentration of 5 ...

  2. CHURCHILL COUNTY, NEVADA ARSENIC STUDY: WATER CONSUMPTION AND EXPOSURE BIOMARKERS

    Science.gov (United States)

    The US Environmental Protection Agency is required to reevaluate the Maximum Contaminant Level (MCL) for arsenic in 2006. To provide data for reducing uncertainties in assessing health risks associated with exposure to low levels (<200 g/l) of arsenic, a large scale biomarker st...

  3. Removal of arsenic from aqueous solution by synthetic hematite ...

    African Journals Online (AJOL)

    A hematite was synthesized and subjected to batch equilibration of arsenic and it's desorption processes that control the mobility, toxicity and availability of arsenic in the water environment. The pHpzc of the synthesized hematite as determined by mass and potentiometric titration techniques were 9.18 and 9.20 respectively.

  4. Cancer excess after arsenic exposure from contaminated milk powder

    DEFF Research Database (Denmark)

    Yorifuji, Takashi; Tsuda, Toshihide; Doi, Hiroyuki

    2011-01-01

    Long-term exposure to inorganic arsenic is related to increased risk of cancer in the lung, skin, bladder, and, possibly, other sites. However, little is known about the consequences of developmental exposures in regard to cancer risk. During early summer in 1955, mass arsenic poisoning of infants...

  5. Arsenic contamination levels in drinking water sources in mining ...

    African Journals Online (AJOL)

    Arsenic contamination in drinking water is a public health problem all over the World especially in mining areas. The study herein reported assessed the concentration levels of arsenic in some drinking water sources in the mining areas in the Lake Victoria Basin and investigated the potential for its removal by adsorption ...

  6. Protective effect of nitric oxide against arsenic-induced oxidative ...

    African Journals Online (AJOL)

    Nitric oxide (NO) is a key molecule involved in many physiology processes. The effects of NO on alleviating arsenic-induced oxidative damage in tall fescue leaves were investigated. Arsenic (25 M) treatment induced significantly accumulation of reactive oxygen species (ROS) and led to serious lipid peroxidation in tall ...

  7. Arsenic from community water fluoridation: quantifying the effect.

    Science.gov (United States)

    Peterson, Emily; Shapiro, Howard; Li, Ye; Minnery, John G; Copes, Ray

    2016-04-01

    Community water fluoridation is a WHO recommended strategy to prevent dental carries. One debated concern is that hydrofluorosilicic acid, used to fluoridate water, contains arsenic and poses a health risk. This study was undertaken to determine if fluoridation contributes to arsenic in drinking water, to estimate the amount of additional arsenic associated with fluoridation, and compare this to the National Sanitation Foundation/American National Standards Institute (NSF/ANSI) standard and estimates from other researchers. Using surveillance data from Ontario drinking water systems, mixed effects linear regression was performed to examine the effect of fluoridation status on the difference in arsenic concentration between raw water and treated water samples. On average, drinking water treatment was found to reduce arsenic levels in water in both fluoridated and non-fluoridated systems by 0.2 μg/L. However, fluoridated systems were associated with an additional 0.078 μg/L (95% CI 0.021, 0.136) of arsenic in water when compared to non-fluoridated systems (P = 0.008) while controlling for raw water arsenic concentrations, types of treatment processes, and source water type. Our estimate is consistent with concentrations expected from other research and is less than 10% of the NSF/ANSI standard of 1 μg/L arsenic in water. This study provides further information to inform decision-making regarding community water fluoridation.

  8. 40 CFR 61.184 - Ambient air monitoring for inorganic arsenic.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Ambient air monitoring for inorganic... for Inorganic Arsenic Emissions From Arsenic Trioxide and Metallic Arsenic Production Facilities § 61.184 Ambient air monitoring for inorganic arsenic. (a) The owner or operator of each source to which...

  9. Effects of organic matter and ageing on the bioaccessibility of arsenic

    Energy Technology Data Exchange (ETDEWEB)

    Meunier, Louise; Koch, Iris [Environmental Sciences Group, Royal Military College, P.O. Box 17 000, Station Forces, Kingston, Ontario K7K7B4 (Canada); Reimer, Kenneth J., E-mail: reimer-k@rmc.ca [Environmental Sciences Group, Royal Military College, P.O. Box 17 000, Station Forces, Kingston, Ontario K7K7B4 (Canada)

    2011-10-15

    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%).

  10. PEPTIDE BINDING AS A MODE OF ACTION FOR THE CARCINOGENICITY AND TOXICITY OF ARSENIC

    Science.gov (United States)

    Arsenic exposure leads to tumors in human skin, lung, urinary bladder, kidney and liver. Three likely initial stages of arsenical-macromolecular interaction are (1) binding of trivalent arsenicals to the sulfhydryl groups of peptides and proteins, (2) arsenical-induced generation...

  11. A microbial arsenic cycle in sediments of an acidic mine impoundment: Herman Pit, Clear Lake, California

    Science.gov (United States)

    Blum, Jodi S.; McCann, Shelley; Bennett, S.; Miller, Laurence G.; Stolz, J. R.; Stoneburner, B.; Saltikov, C.; Oremland, Ronald S.

    2015-01-01

    The involvement of prokaryotes in the redox reactions of arsenic occurring between its +5 [arsenate; As(V)] and +3 [arsenite; As(III)] oxidation states has been well established. Most research to date has focused upon circum-neutral pH environments (e.g., freshwater or estuarine sediments) or arsenic-rich “extreme” environments like hot springs and soda lakes. In contrast, relatively little work has been conducted in acidic environments. With this in mind we conducted experiments with sediments taken from the Herman Pit, an acid mine drainage impoundment of a former mercury (cinnabar) mine. Due to the large adsorptive capacity of the abundant Fe(III)-rich minerals, we were unable to initially detect in solution either As(V) or As(III) added to the aqueous phase of live sediment slurries or autoclaved controls, although the former consumed added electron donors (i.e., lactate, acetate, hydrogen), while the latter did not. This prompted us to conduct further experiments with diluted slurries using the live materials from the first incubation as inoculum. In these experiments we observed reduction of As(V) to As(III) under anoxic conditions and reduction rates were enhanced by addition of electron donors. We also observed oxidation of As(III) to As(V) in oxic slurries as well as in anoxic slurries amended with nitrate. We noted an acid-tolerant trend for sediment slurries in the cases of As(III) oxidation (aerobic and anaerobic) as well as for anaerobic As(V) reduction. These observations indicate the presence of a viable microbial arsenic redox cycle in the sediments of this extreme environment, a result reinforced by the successful amplification of arsenic functional genes (aioA, and arrA) from these materials.

  12. Assessing models of arsenic occurrence in drinking water from bedrock aquifers in New Hampshire

    Science.gov (United States)

    Andy, Caroline; Fahnestock, Maria Florencia; Lombard, Melissa; Hayes, Laura; Bryce, Julie; Ayotte, Joseph

    2017-01-01

    Three existing multivariate logistic regression models were assessed using new data to evaluate the capacity of the models to correctly predict the probability of groundwater arsenic concentrations exceeding the threshold values of 1, 5, and 10 micrograms per liter (µg/L) in New Hampshire, USA. A recently released testing dataset includes arsenic concentrations from groundwater samples collected in 2004–2005 from a mix of 367 public-supply and private domestic wells. The use of this dataset to test three existing logistic regression models demonstrated enhanced overall predictive accuracy for the 5 and 10 μg/L models. Overall accuracies of 54.8, 76.3, and 86.4 percent were reported for the 1, 5, and 10 μg/L models, respectively. The state was divided by counties into northwest and southeast regions. Regional differences in accuracy were identified; models had an average accuracy of 83.1 percent for the counties in the northwest and 63.7 percent in the southeast. This is most likely due to high model specificity in the northwest and regional differences in arsenic occurrence. Though these models have limitations, they allow for arsenic hazard assessment across the region. The introduction of well-type (public or private), well depth, and casing length as explanatory variables may be appropriate measures to improve model performance. Our findings indicate that the original models generalize to the testing dataset, and should continue to serve as an important vehicle of preventative public health that may be applied to other groundwater contaminants in New Hampshire.

  13. Control of geochemical mobility of arsenic by liming in materials subjected to acid mine drainage

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, R.P. de; Figueiredo, B.R. [Geoscience Inst., UNICAMP, SP (Brazil); Mello, J.W.V. de; Santos, J.C.Z.; Zandonadi, L.U. [Soil Dept., Federal Univ. of Vicosa, MG (Brazil)

    2008-04-15

    Background. Acid mine drainage (AMD) results from the exposure of sulfide materials to atmospheric water and oxygen. In addition to AMD, oxidation of arsenopyrite and other As-bearing sulfides can release arsenic (As) into the environment. In view of the risk to living organisms due to contamination of ground and surface water sources with As, this work was carried out to evaluate the effectiveness of lime (CaCO{sub 3}) in controlling the dispersion of this metalloid in the environment. Methods. Partially oxidized samples of sulfide bearing materials from gold mines in Brazil were used to evaluate the arsenic mobilization by leaching tests. Columns containing ground samples, with and without liming treatments, were leached with distilled water every two weeks over a 156-day period. Results and discussion. The acid-base accounting (ABA) static tests classified the samples as potential acid forming materials. In the treatments without liming, As, Fe and S concentrations in the leachates were higher than after treatment with carbonate. Nevertheless, the effectiveness of liming and As mobilization were lower in the sample containing goethite. A high correlation between Fe and As concentrations in the leachates (r=0.749) suggests that iron (hydr)oxides retained arsenic in the solid phase. Oxidation rates of As bearing sulfides were increased at low pH (2.0-3.9), probably due to the enhanced activity of bacteria (Acidithiobacillus) and decreased rate of Fe precipitation, thus reinforcing generation of acid water, and consequently releasing As. Conclusions and perspectives. Our results corroborate the use of lime to control the dispersion of As in AMD-affected environments. However, the effectiveness of the liming treatment seems to be dependent on the presence of iron (hydr)oxides in the sample. These findings can be useful to remediate areas affected by acid mine drainage and arsenic mobilization in partially oxidized sulfide materials. (orig.)

  14. Nanoencapsulation of DMSA monoester for better therapeutic efficacy of the chelating agent against arsenic toxicity.

    Science.gov (United States)

    Yadav, Abhishek; Mathur, Rashi; Samim, Mohammed; Lomash, Vinay; Kushwaha, Pramod; Pathak, Uma; Babbar, Anil Kumar; Flora, Swaran Jeet Singh; Mishra, Anil Kumar; Kaushik, Mahabir Parshad

    2014-04-01

    Exposure to toxic metals remains a widespread occupational and environmental problem in world. Chelation therapy is a mainstream treatment used to treat heavy metal poisoning. This paper describes the synthesis, characterization and therapeutic evaluation of monoisoamyl 2,3-dimercaptosuccinic acid (MiADMSA)-encapsulated polymeric nanoparticles as a detoxifying agent for arsenic poisoning. Polymeric nanoparticles entrapping the DMSA monoester, which can evade the reticulo-endothelial system and have a long circulation time in the blood, were prepared. Particle characterization was carried out by transmission electron microscopy and dynamic light scattering. An in vivo study was conducted to investigate the therapeutic efficacy of MiADMSA-encapsulated polymeric nanoparticles (nano- MiADMSA; 50 mg/kg orally for 5 days) and comparison drawn with bulk MiADMSA. Swiss albino mice exposed to sodium arsenite for 4 weeks were treated for 5 days to evaluate alterations in blood, brain, kidney and liver oxidative stress variables. The study also evaluated the histopathological changes in tissues and the chelating potential of the nanoformulation. Our results show that nano-MiADMSA have a narrow size distribution in the 50-nm range. We observed an enhanced chelating potential of nano-MiADMSA compared with bulk MiADMSA as evident in the reversal of biochemical changes indicative of oxidative stress and efficient removal of arsenic from the blood and tissues. Histopathological changes and urinary 8-OHdG levels also prove better therapeutic efficacy of the novel formulation for arsenic toxicity. The results from our study show better therapeutic efficacy of nano-MiADMSA in removing arsenic burden from the brain and liver.

  15. A novel method to remove arsenic from water

    Science.gov (United States)

    McDonald, Kyle J.

    Arsenic is a toxic metalloid that is found ubiquitously in earth's crust. The release of arsenic into the aqueous environment and the subsequent contamination in drinking water supplies is a worldwide health crisis. Arsenic is the culprit of the largest mass poisoning of a population in history and the number one contaminant of concern in the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) Priority List of Hazardous Substances. Practical, affordable, and reliable treatment technologies have yet to be developed due to the difficulty in overcoming many socioeconomic and geochemical barriers. Recent studies have reported that cupric oxide (CuO) nanoparticles have shown promising characteristics as a sorbent to remove arsenic from water. However, these studies were conducted in controlled environments and have yet to test the efficacy of this treatment technology in the field. In this manuscript, a flow through adsorption column containing CuO nanoparticles was developed for lab based studies to remove arsenic from water. These studies were expanded to include a field demonstration of the CuO nanoparticle flow through adsorption column to remove naturally occurring arsenic from groundwater associated with agriculture, domestic groundwater, and in situ recovery (ISR) uranium production process water. A major limitation for many treatment technologies is the difficulties presented in the disposal of waste byproducts such as sludge and spent media. In the research contained in this manuscript, we investigate the processes of regenerating the CuO nanoparticles using sodium hydroxide (NaOH). The use of the regenerated CuO nanoparticles was examined in batch experiments and implemented in the flow through column studies. The ability to regenerate and reuse a sorbent drastically reduces costs involved in manufacturing and disposal of spent media. Also, the CuO nanoparticles were evaluated in batch experiments for the removal of naturally

  16. Oral arsenic trioxide poisoning and secondary hazard from gastric content.

    Science.gov (United States)

    Kinoshita, Hidenori; Hirose, Yasuo; Tanaka, Toshiharu; Yamazaki, Yoshihiko

    2004-12-01

    In a suicide attempt, a 54-year-old man ingested arsenic trioxide. Gastric lavage was performed, but most of the poison remained as a mass in his stomach. A total gastrectomy was also performed to avoid intestinal perforation and arsenic poisoning. After the operation, he developed ventricular fibrillation. At one point, his circulation recovered spontaneously, but he later died from refractory circulatory failure. Many medical staff members were exposed to fumes from the patient's stomach. Some of the staff were diagnosed with corneal erosion or laryngitis. Because arsenic trioxide reacts with acid to produce arsine, the symptoms experienced by medical staff are directly attributable to arsine produced as a result of the reaction of arsenic trioxide with gastric acid. This case highlights the need for the introduction of protective measures to safeguard medical staff from exposure to arsine gas during the treatment of patients poisoned from ingested arsenic trioxide.

  17. [Speciation analysis and toxicity of arsenic in realgar bioleaching solution].

    Science.gov (United States)

    Zhang, Jing-hong; Fan, Qin; Li, Hong-yu

    2010-05-01

    To analyze speciation and toxicity of arsenic in realgar bioleaching solution, and to explore its possible relation between speciation and toxicity. Capillary zone electrophoresis (CZE) can be used quickly and simply onto the simultaneous separation and quantitative determination of the speciation of arsenic in realgar bioleaching solution. The effects of three different realgar bioleaching liquids on the acute toxicity level of rat were also investigated as well. Parallel experiments with traditional processing realgar via gastric irrigation were conducted for comparison. There are three different arsenic species in realgar bioleaching solution (iAs(III), iAs(V) MMA(V)), and the processing method largely affected speciation and toxicity of arsenic of it. It was found that the toxicity level was decreased through increasing the amount of MMA(V). These results indicate that the species of arsenic may be tightly relationship to its toxicity in realgar bioleaching solution.

  18. Arsenic Precipitation in the Bioleaching of Realgar Using Acidithiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Peng Chen

    2013-01-01

    Full Text Available The current study investigates the characteristics of arsenic precipitation during the bioleaching of realgar. The bioleaching performance of Acidithiobacillus ferrooxidans BY-3 (A. ferrooxidans was investigated through scanning electron microscopy (SEM, transmission electron microscopy (TEM, X-ray diffraction (XRD, and Fourier transform infrared (FT-IR spectrophotometry. SEM and XRD analyses revealed that the arsenic-adapted strain of A. ferrooxidans was more hydrophobic and showed higher attachment efficiency to realgar compared with the wild strain. The arsenic precipitation using A. ferrooxidans resulted in the precipitation of an arsenic-rich compound on the surface of the bacterial cell, as shown in the TEM images. The FT-IR spectra suggested that the −OH and −NH groups were closely involved in the biosorption process. The observations above strongly suggest that the cell surface of A. ferrooxidans plays a role in the induction of arsenic tolerance during the bioleaching of realgar.

  19. Influence of transmembrane pressure and feed concentration on the retention of arsenic, chromium and cadmium from water by nanofiltration.

    Science.gov (United States)

    Babaee, Yasser; Mousavi, Seyed Mahmoud; Danesh, Shahnaz; Baratian, Ali

    2010-01-01

    One of the main toxic pollutants in drinking water is heavy metals which must be reduced to standard levels. Removal of trace amounts of heavy metals can be achieved by means of membrane processes such as nanofiltration. The removal efficiency of a nanofiltration membrane is strongly affected by operating conditions. The present study focused on the effect of two key parameters, i.e., transmembrane pressure and feed concentration on the removal of heavy metals (arsenic, chromium and cadmium) from water by a polymeric nanofiltration membrane UTC-70UB charged negatively. The rejection experiments included variation of heavy metals feed concentrations in the range of 100 to 400 microg/L for arsenic and chromium and 20 to 80 microg/L for cadmium, and different transmembrane pressures in the range of 5 to 14 bar. The results indicated that under most conditions tested in this research, the rejection of heavy metals was found to increase when the transmembrane pressure was increased. The results also showed the high rejection percentage of the heavy metals, with the maximum retention values of arsenic, cadmium and chromium, 97%, 100% and 95% respectively. The percent reduction of arsenic and chromium was found to enhance as their concentration in the feed increased. However, in the case of cadmium, the rejection was reduced with increase in the concentration.

  20. Protective effect of edible marine algae, Laminaria japonica and Porphyra haitanensis, on subchronic toxicity in rats induced by inorganic arsenic.

    Science.gov (United States)

    Jiang, Yanhua; Wang, Lianzhu; Yao, Lin; Liu, Zhantao; Gao, Hua

    2013-09-01

    Arsenic, a potent environmental toxic agent, causes various hazardous effects on human health. This study was performed to evaluate the protective effects of edible marine algae, Laminaria japonica and Porphyra haitanensis, on subchronic stress of rats induced by arsenic trioxide (As2O3). The co-treatment of marine algae could slightly increase the growth rates of body weights compared to the As2O3-treated group. The marine algae application restored liver and renal function by preventing the increment in the activities of alanine transaminase and alkaline phosphatase, and the levels of total protein, blood urea nitrogen, and creatinine. The increase in the contents of total cholesterol, triglyceride, and low density lipoprotein cholesterol, and decrease in the contents of high density lipoprotein cholesterol were observed in algae co-treated groups which indicated that marine algae could reverse the abnormal lipid metabolisms induced by arsenic. Moreover, these algae could protect the rats from lipid peroxidation by restoring the depletion of superoxide dismutase and glutathione peroxidase activities and sulfhydryl group contents, and lowering the enhanced malondialdehyde contents. Therefore, evidences indicate that L. japonica and P. haitanensis can serve as an effective regimen for treating arsenic poisoning.

  1. Arsenic Species in Drinking Water Wells in the USA with High Arsenic Concentrations

    Science.gov (United States)

    As part of the United States Environmental Protection Agency (USEPA) arsenic treatment demonstration program, 65 five well waters scattered across the US were speciated for As(III) and As(V). The speciation test data showed that most (60) well waters had one dominant species, but...

  2. Diverse arsenic- and iron-cycling microbial communities in arsenic-contaminated aquifers used for drinking water in Bangladesh.

    NARCIS (Netherlands)

    Hassan, Z.; Sultana, M.; van Breukelen, B.M.; Kahn, S.I.; Roling, W.F.M.

    2015-01-01

    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

  3. METHYLATED TRIVALENT ARSENICALS AS CANDIDATE ULTIMATE GENOTOXIC FORMS OF ARSENIC: INDUCTION OF CHROMOSOMAL MUTATIONS BUT NOT GENE MUTATIONS

    Science.gov (United States)

    ABSTRACT Arsenic is a prevalent human carcinogen whose mutagenicity has not been characterized fully. Exposure to either form of inorganic arsenic, AsIII or AsV, can result in the formation of at least four organic metabolites: monomethylarsonic acid, monomethylarsonous aci...

  4. Creatinine, Diet, Micronutrients, and Arsenic Methylation in West Bengal, India

    Science.gov (United States)

    Basu, Arin; Mitra, Soma; Chung, Joyce; Guha Mazumder, D.N.; Ghosh, Nilima; Kalman, David; von Ehrenstein, Ondine S.; Steinmaus, Craig; Liaw, Jane

    2011-01-01

    Background: Ingested inorganic arsenic (InAs) is methylated to monomethylated (MMA) and dimethylated metabolites (DMA). Methylation may have an important role in arsenic toxicity, because the monomethylated trivalent metabolite [MMA(III)] is highly toxic. Objectives: We assessed the relationship of creatinine and nutrition—using dietary intake and blood concentrations of micronutrients—with arsenic metabolism, as reflected in the proportions of InAS, MMA, and DMA in urine, in the first study that incorporated both dietary and micronutrient data. Methods: We studied methylation patterns and nutritional factors in 405 persons who were selected from a cross-sectional survey of 7,638 people in an arsenic-exposed population in West Bengal, India. We assessed associations of urine creatinine and nutritional factors (19 dietary intake variables and 16 blood micronutrients) with arsenic metabolites in urine. Results: Urinary creatinine had the strongest relationship with overall arsenic methylation to DMA. Those with the highest urinary creatinine concentrations had 7.2% more arsenic as DMA compared with those with low creatinine (p < 0.001). Animal fat intake had the strongest relationship with MMA% (highest tertile animal fat intake had 2.3% more arsenic as MMA, p < 0.001). Low serum selenium and low folate were also associated with increased MMA%. Conclusions: Urine creatinine concentration was the strongest biological marker of arsenic methylation efficiency, and therefore should not be used to adjust for urine concentration in arsenic studies. The new finding that animal fat intake has a positive relationship with MMA% warrants further assessment in other studies. Increased MMA% was also associated, to a lesser extent, with low serum selenium and folate. PMID:21652291

  5. Transcriptomic Response of Purple Willow (Salix purpurea to Arsenic Stress

    Directory of Open Access Journals (Sweden)

    Aymeric Yanitch

    2017-06-01

    Full Text Available Arsenic (As is a toxic element for plants and one of the most common anthropogenic pollutants found at contaminated sites. Despite its severe effects on plant metabolism, several species can accumulate substantial amounts of arsenic and endure the associated stress. However, the genetic mechanisms involved in arsenic tolerance remains obscure in many model plant species used for land decontamination (phytoremediation, including willows. The present study assesses the potential of Salix purpurea cv. ‘Fish Creek’ for arsenic phytoextraction and reveals the genetic responses behind arsenic tolerance, phytoextraction and metabolism. Four weeks of hydroponic exposure to 0, 5, 30 and 100 mg/L revealed that plants were able to tolerate up to 5 mg/L arsenic. Concentrations of 0 and 5 mg/L of arsenic treatment were then used to compare alterations in gene expression of roots, stems and leaves using RNA sequencing. Differential gene expression revealed transcripts encoding proteins putatively involved in entry of arsenic into the roots, storage in vacuoles and potential transport through the plant as well as primary and secondary (indirect toxicity tolerance mechanisms. A major role for tannin as a compound used to relieve cellular toxicity is implicated as well as unexpected expression of the cadmium transporter CAX2, providing a potential means for internal arsenic mobility. These insights into the underpinning genetics of a successful phytoremediating species present novel opportunities for selection of dedicated arsenic tolerant crops as well as the potential to integrate such tolerances into a wider Salix ideotype alongside traits including biomass yield, biomass quality, low agricultural inputs and phytochemical production.

  6. Transcriptomic Response of Purple Willow (Salix purpurea) to Arsenic Stress

    Science.gov (United States)

    Yanitch, Aymeric; Brereton, Nicholas J. B.; Gonzalez, Emmanuel; Labrecque, Michel; Joly, Simon; Pitre, Frederic E.

    2017-01-01

    Arsenic (As) is a toxic element for plants and one of the most common anthropogenic pollutants found at contaminated sites. Despite its severe effects on plant metabolism, several species can accumulate substantial amounts of arsenic and endure the associated stress. However, the genetic mechanisms involved in arsenic tolerance remains obscure in many model plant species used for land decontamination (phytoremediation), including willows. The present study assesses the potential of Salix purpurea cv. ‘Fish Creek’ for arsenic phytoextraction and reveals the genetic responses behind arsenic tolerance, phytoextraction and metabolism. Four weeks of hydroponic exposure to 0, 5, 30 and 100 mg/L revealed that plants were able to tolerate up to 5 mg/L arsenic. Concentrations of 0 and 5 mg/L of arsenic treatment were then used to compare alterations in gene expression of roots, stems and leaves using RNA sequencing. Differential gene expression revealed transcripts encoding proteins putatively involved in entry of arsenic into the roots, storage in vacuoles and potential transport through the plant as well as primary and secondary (indirect) toxicity tolerance mechanisms. A major role for tannin as a compound used to relieve cellular toxicity is implicated as well as unexpected expression of the cadmium transporter CAX2, providing a potential means for internal arsenic mobility. These insights into the underpinning genetics of a successful phytoremediating species present novel opportunities for selection of dedicated arsenic tolerant crops as well as the potential to integrate such tolerances into a wider Salix ideotype alongside traits including biomass yield, biomass quality, low agricultural inputs and phytochemical production. PMID:28702037

  7. Performance of a zerovalent iron reactive barrier for the treatment of arsenic in groundwater: Part 2. Geochemical modeling and solid phase studies

    Science.gov (United States)

    Beak, Douglas G.; Wilkin, Richard T.

    2009-04-01

    Arsenic uptake processes were evaluated in a zerovalent iron reactive barrier installed at a lead smelting facility using geochemical modeling, solid-phase analysis, and X-ray absorption spectroscopy techniques. Aqueous speciation of arsenic is expected to play a key role in directing arsenic uptake processes. Geochemical modeling reveals contrasting pH-dependencies for As(III) and As(V) precipitation. At the moderately alkaline pH conditions typically encountered in zerovalent iron reactive barriers, As(III) is unlikely to precipitate as an oxide or a sulfide phase. Conversely, increasing pH is expected to drive precipitation of metal arsenates including ferrous arsenate. Bacterially mediated sulfate reduction plays an important role in field installations of granular iron. Neoformed iron sulfides provide surfaces for adsorption of oxyanion and thioarsenic species of As(III) and As(V) and are expected to provide enhanced arsenic removal capacity. X-ray absorption near edge structure (XANES) spectra indicate that arsenic is sequestered in the solid phase as both As(III) and As(V) in coordination environments with O and S. Arsenic removal in the PRB probably results from several pathways, including adsorption to iron oxide and iron sulfide surfaces, and possible precipitation of ferrous arsenate. Corrosion of granular iron appears to result in some As(III) oxidation to As(V) as the proportion of As(V) to As(III) in the solid phase is greater compared to influent groundwater. As(0) was not detected in the PRB materials. These results are broadly comparable to laboratory based studies of arsenic removal by zerovalent iron, but additional complexity is revealed in the field environment, which is largely due to the influence of subsurface microbiota.

  8. The effect of seafood consumption on the assessment of occupational exposure to arsenic by urinary arsenic speciation measurements.

    Science.gov (United States)

    Arbouine, M W; Wilson, H K

    1992-09-01

    The determination of arsenite, arsenate, dimethylarsenic acid (DMA) and monomethylarsonic acid (MMA) in urine has been used for assessing occupational exposure to inorganic arsenic because these species were thought to be unaffected by dietary arsenic. However, this investigation reports how the consumption of certain types of seafood can lead to an increase in the amount of DMA excreted and hence an elevation in the urinary arsenic speciation total. Urine samples collected from volunteers between 4-20 hours after the ingestion of moderate-sized portions of mackerel, herring, crab or tuna, showed mean increases in the arsenic speciation totals of between 1.8 and 6.9 times compared with the levels in samples collected before the seafood was consumed. These findings have important implications in devising a biological monitoring strategy for workers exposed to inorganic arsenic.

  9. 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.

  10. Imbalanced immune responses involving inflammatory molecules and immune-related pathways in the lung of acute and subchronic arsenic-exposed mice.

    Science.gov (United States)

    Li, Jinlong; Zhao, Lu; Zhang, Yang; Li, Wei; Duan, Xiaoxu; Chen, Jinli; Guo, Yuanyuan; Yang, Shan; Sun, Guifan; Li, Bing

    2017-11-01

    Inorganic arsenic has been claimed to increase the risk of pulmonary diseases through ingestion, as opposed to inhalation, which makes it a unique and intriguing environmental toxicant. However, the immunotoxic effects of lung, one of the targets of arsenic exposure, have not been extensively investigated in vivo. In the present study, we first confirmed that 2.5, 5 and 10mg/kg NaAsO2 orally for 24h dose-dependently triggered the infiltration of neutrophils, lymphocytes and macrophages in BALF. Not only the transcription activity, but also the secretion of proinflammatory cytokines IL-1β, IL-6 and TNF-α were consistently raised in the lung and BALF of acute arsenic-exposed mice. Acute oral administration of NaAsO2 also raised pulmonary MPO activity and mRNA levels of chemokine Mip-2 and Mcp-1. Meanwhile, obvious histopathological damages with inflammatory cells infiltration and erythrocyte aggregation around the capillaries were verified in the lung of mice drank arsenic-rich water freely for 3 months. Furthermore, we affirmed notable disturbance of CD4+ T-cell differentiation in the lung of acute arsenic-exposed mice, as demonstrated by up-regulated mRNA levels of regulator Gata3 and cytokine Il-4 of Th2, enhanced Foxp3 and Il-10 of Treg, down-regulated T-bet and Ifn-γ of Th1, as well as lessened Ror-γt and Il-23 of Th17. However, impressive elevation of cytokine Ifn-γ and Il-23, as well as moderate enhancement of Il-4 and Il-10 were found in the lung by subchronic arsenic administration. Finally, our present study demonstrated that both a single and sustained arsenic exposure prominently increased the expression of immune-related p38, JNK, ERK1/2 and NF-κB proteins in the lung tissue. While disrupting the pulmonary redox homeostasis by increasing MDA levels, exhausting GSH and impaired enzyme activities of CAT and GSH-Px, antioxidant regulator NRF2 and its downstream targets HO-1 and GSTO1/2 were also up-regulated by both acute and subchronic arsenic

  11. Evaluation of innovative arsenic treatment technologies :the arsenic water technology partnership vendors forums summary report.

    Energy Technology Data Exchange (ETDEWEB)

    Everett, Randy L.; Siegel, Malcolm Dean; McConnell, Paul E.; Kirby, Carolyn (Comforce Technical Services, Inc.)

    2006-09-01

    The lowering of the drinking water standard (MCL) for arsenic from 50 {micro}g/L to 10 {micro}g/L in January 2006 could lead to significant increases in the cost of water for many rural systems throughout the United States. The Arsenic Water Technology Partnership (AWTP), a collaborative effort of Sandia National Laboratories, the Awwa Research Foundation (AwwaRF) and WERC: A Consortium for Environmental Education and Technology Development, was formed to address this problem by developing and testing novel treatment technologies that could potentially reduce the costs of arsenic treatment. As a member of the AWTP, Sandia National Laboratories evaluated cutting-edge commercial products in three annual Arsenic Treatment Technology Vendors Forums held during the annual New Mexico Environmental Health Conferences (NMEHC) in 2003, 2004 and 2005. The Forums were comprised of two parts. At the first session, open to all conference attendees, commercial developers of innovative treatment technologies gave 15-minute talks that described project histories demonstrating the effectiveness of their products. During the second part, these same technologies were evaluated and ranked in closed sessions by independent technical experts for possible use in pilot-scale field demonstrations being conducted by Sandia National Laboratories. The results of the evaluations including numerical rankings of the products, links to company websites and copies of presentations made by the representatives of the companies are posted on the project website at http://www.sandia.gov/water/arsenic.htm. This report summarizes the contents of the website by providing brief descriptions of the technologies represented at the Forums and the results of the evaluations.

  12. Study of Arsenic Presence in Drinking Water Sources: A Case Study

    OpenAIRE

    Kamali, Z.; Borghei, M.; AM Hassani; H Taghipour; M Mosaferi; Ghadirzadeh, A.

    2008-01-01

    Background and Objectives: Conducted studies about arsenic have shown that consumption of water contaminated with arsenic can causes different adverse health effects in consumers. World Health Organization (WHO) has enacted 10µg/L arsenic in drinking water as a guideline value. Regarding some reports about arsenic presence in a village of Hashtrood county and related health effects and also considering this fact that determination of arsenic as a poisoning chemical is not included in ro...

  13. 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 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 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.

  14. Arsenical injury through the bark of fruit trees

    Energy Technology Data Exchange (ETDEWEB)

    Swingle, D.B.; Morris, H.E.

    1917-02-19

    The periderm on the smooth bark of apple trees is practically impervious to arsenical solutions. If such solutions are admitted during the growing season, more or less injury will follow. The solutions may be admitted through wounds, lenticels, or latent buds. As the trees become older and rough bark is produced, the cracks made in its production will admit arsenical solutions to the inner tissues, which will be injured. Roots and branches of equal size and with similar bark are about equally susceptible to arsenical injury. If the injury is rapid, for example, the arsenic gaining entrance through a wound in the smooth bark, very definite longitudinal streaks will be produced in the bark and sapwood. If the injury is slow, the arsenic gradually entering through cracks of the normal rough bark, such streaks are very little in evidence. Paint applied to fresh wounds offers a partial, but not complete protection. Of the arsenical compounds used as insecticides, calcium arsenite is the most injurious when admitted to the inner bark. The injury is not necessarily due to impurities in the arsenical compounds. 11 references, 11 tables.

  15. Arsenic exposure to smelter workers. Clinical and neurophysiological studies

    Energy Technology Data Exchange (ETDEWEB)

    Blom, S.; Lagerkvist, B.; Linderholm, H.

    1985-08-01

    Forty-seven copper smelter workers, exposed to airborne arsenic for 8-40 years, were examined clinically with electromyography, and the motor and sensory conduction velocities in their arms and legs were determined. Fifty age-matched industrial workers not exposed to arsenic formed a reference group. The level of arsenic in the air at the smeltery was estimated to be below 500 micrograms/mT before 1975 and approximately 50 micrograms/mT thereafter. Urine analyses of arsenic showed a mean value of 71 micrograms/l (1 mumol/l) in the exposed group; this value is lower than that found in earlier studies reporting clinically detectable neuropathy. A slightly reduced nerve conduction velocity in two or more peripheral nerves was more common among the arsenic workers than the referents, and a statistically significant correlation between cumulative exposure to arsenic and reduced nerve conduction velocity in three peripheral motor nerves was found. This occurrence was interpreted as a sign of slight subclinical neuropathy. In conclusion the risk of clinically significant neuropathy is small when exposure is kept below 50 micrograms/mT in workroom air. The subclinical findings may be of interest in relation to the prevention of early adverse health effects from arsenic exposure.

  16. 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.

  17. Stabilization of arsenic sludge with mechanochemically modified zero valent iron.

    Science.gov (United States)

    Liang, Yanjie; Min, Xiaobo; Chai, Liyuan; Wang, Mi; Liyang, Wenjun; Pan, Qinglin; Okido, Masazumi

    2017-02-01

    Modified zero valent iron (ZVI) is obtained from commercial iron powder co-ground with manganese dioxide (MnO2) in intensive mechanical stress. The result indicates that the modified ZVI is very effective in arsenic sludge stabilization with a declination of arsenic leaching contraction from 72.50 mg/L to 0.62 mg/L, much lower than that of ordinary ZVI (10.48 mg/L). The involved process, including mechanochemical activation, corrosion and arsenic adsorption, is characterized explicitly to verify the improved arsenic stabilization mechanism. It shows that the mechanically formed Fe-Mn binary oxides layer results in an intensive corrosion extent, generating a mass of corrosion products. Moreover, as the emergence of Mn will restrain the process of iron (hydr)oxides crystallization, the ultimate corrosion products of the modified ZVI predominates in amorphous iron (hydr)oxides, performing much better in arsenic absorption. According to the BCR analysis, unstable arsenic in sludge is easily transformed to residual fraction by the help of amorphous iron (hydr)oxides, resulting in a restrained environmental availability of arsenic sludge after the modified ZVI stabilization. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Arsenic rich iron plaque on macrophyte roots - an ecotoxicological risk?

    Energy Technology Data Exchange (ETDEWEB)

    Taggart, M.A. [School of Biological Sciences, University of Aberdeen, Cruickshank Bld, St Machar Drive, Aberdeen, AB24 3UU (United Kingdom); Instituto de Investigacion en Recursos Cinegeticos, IREC (CSIC-UCLM-JCCM), Ronda de Toledo s/n, 13005 Ciudad Real (Spain)], E-mail: mark.taggart@uclm.es; Mateo, R. [Instituto de Investigacion en Recursos Cinegeticos, IREC (CSIC-UCLM-JCCM), Ronda de Toledo s/n, 13005 Ciudad Real (Spain); Charnock, J.M.; Bahrami, F. [Synchrotron Radiation Department, CCLRC Daresbury Laboratory, Warrington, Cheshire, WA4 4AD (United Kingdom); Green, A.J. [Department of Wetland Ecology, Estacion Biologica de Donana, CSIC, Pabellon del Peru, Avenida Maria Luisa s/n, 41013 Seville (Spain); Meharg, A.A. [School of Biological Sciences, University of Aberdeen, Cruickshank Bld, St Machar Drive, Aberdeen, AB24 3UU (United Kingdom)

    2009-03-15

    Arsenic is known to accumulate with iron plaque on macrophyte roots. Three to four years after the Aznalcollar mine spill (Spain), residual arsenic contamination left in seasonal wetland habitats has been identified in this form by scanning electron microscopy. Total digestion has determined arsenic concentrations in thoroughly washed 'root + plaque' material in excess of 1000 mg kg{sup -1}, and further analysis using X-ray absorption spectroscopy suggests arsenic exists as both arsenate and arsenite. Certain herbivorous species feed on rhizomes and bulbs of macrophytes in a wide range of global environments, and the ecotoxicological impact of consuming arsenic rich iron plaque associated with such food items remains to be quantified. Here, greylag geese which feed on Scirpus maritimus rhizome and bulb material in areas affected by the Aznalcollar spill are shown to have elevated levels of arsenic in their feces, which may originate from arsenic rich iron plaque. - Accumulation of metals with iron plaque on macrophyte roots in wetlands poses an ecotoxicological risk to certain herbivores.

  19. Ground Water Arsenic Contamination: A Local Survey in India.

    Science.gov (United States)

    Kumar, Arun; Rahman, Md Samiur; Iqubal, Md Asif; Ali, Mohammad; Niraj, Pintoo Kumar; Anand, Gautam; Kumar, Prabhat; Abhinav; Ghosh, Ashok Kumar

    2016-01-01

    In the present times, arsenic poisoning contamination in the ground water has caused lots of health-related problems in the village population residing in middle Gangetic plain. In Bihar, about 16 districts have been reported to be affected with arsenic poisoning. For the ground water and health assessment, Simri village of Buxar district was undertaken which is a flood plain region of river Ganga. In this study, 322 water samples were collected for arsenic estimation, and their results were analyzed. Furthermore, the correlation between arsenic contamination in ground water with depth and its distance from river Ganga were analyzed. Results are presented as mean ± standard deviation and total variation present in a set of data was analyzed through one-way analysis of variance. The difference among mean values has been analyzed by applying Dunnett's test. The criterion for statistical significance was set at P Halwa Patti and Doodhi Patti strips were the most affected strips with high-arsenic concentration in hand pumps. Furthermore, a correlation between the arsenic concentration with the depth of the hand pumps and the distance from the river Ganga was also a significant study. The present study concludes that in Simri village there is high contamination of arsenic in ground water in all the strips. Such a huge population is at very high risk leading the village on the verge of causing health hazards among them. Therefore, an immediate strategy is required to combat the present problem.

  20. 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.

  1. Extremely high urine arsenic level after remote seafood ingestion.

    Science.gov (United States)

    Nañagas, Kristine A; Tormoehlen, Laura M

    2014-01-01

    Urine testing for heavy metal concentrations is increasingly performed in the outpatient setting as a part of laboratory evaluation for neuropathy. Abnormal urine arsenic levels due to dietary intake of organic arsenic can lead to unnecessary chelation therapy. A 54-year-old man underwent a 24-hour urine collection for heavy metal concentrations in evaluation of paresthesia of the right foot. The total arsenic level was 8880 μg/d with concentrations of 4749 μg/L and 3769 μg/g creatinine. He was urgently referred to the toxicology clinic for consideration of chelation therapy. History revealed consumption of 2 lobster tails 5 days before the testing. Speciation was then performed on the original urine specimen and revealed an organic arsenic concentration of 4332 μg/L. No inorganic or methylated arsenic was detected. Repeat testing after abstaining from seafood demonstrated a total arsenic level of 50 μg/d with concentrations of 30 μg/L and 21 μg/g creatinine. Our patient demonstrates the highest level of arsenobetaine reported in the literature, and this level is higher than expected for a person who had not consumed seafood for 5 days before testing. The high levels may be due to consumption of food that he did not recognize as containing arsenobetaine or that his clearance of arsenobetaine from the ingested lobster is slower than published ranges. This case demonstrates the importance of speciation when measuring urine arsenic levels to avoid unnecessary chelation therapy.

  2. Beyond regulations: industry voluntary ban in arsenic use.

    Science.gov (United States)

    Hsueh, Lily

    2013-12-15

    Firms play a key role in pollution abatement and control by engaging in beyond-compliance actions without the force of law in voluntary programs. This study examines the effectiveness of a bilateral voluntary agreement, one type of voluntary programs, negotiated between the U.S. Environmental Protection Agency (EPA) and the pressure-treated wood industry to phase-out the use of chromated copper arsenate (CCA), a poisonous arsenic compound. Arsenic is ranked number one on the EPA's priority list of hazardous substances. Unlike a majority of earlier studies on voluntary programs, dynamic panel estimation and structural break analysis show that while a technological innovation in semiconductors is associated with arsenic use increases, the CCA voluntary agreement is associated with a reduction in arsenic use to levels not seen since the 1920s. A voluntary ban in arsenic acid by pesticide manufacturers in the agriculture sector has also contributed to arsenic reductions. Furthermore, the results suggest that environmental activism has played a role in curbing arsenic use. Increasing stakeholder pressures, as measured by membership in the Sierra Club, improves voluntary agreement effectiveness. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. 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.

  4. Distinct arsenic metabolites following seaweed consumption in humans.

    Science.gov (United States)

    Taylor, Vivien F; Li, Zhigang; Sayarath, Vicki; Palys, Thomas J; Morse, Kevin R; Scholz-Bright, Rachel A; Karagas, Margaret R

    2017-06-20

    Seaweeds contain arsenic primarily in the form of arsenosugars, which can be metabolized to a wide range of arsenic compounds. To characterize human exposure to arsenic from seaweed consumption, we determined concentrations of arsenic species in locally available seaweeds, and assessed urinary arsenic compounds in an experimental feeding study. A total of 11 volunteers consumed 10 g per day of three types of seaweeds (nori, kombu, and wakame) for three days each, while abstaining from rice and seafood following a three-day washout period. Urinary arsenosugars and their metabolites (including dimethyl arsenate (DMA), thio-dimethylarsinoylethanol (thio-DMAE), thio-dimethylarsinoylacetate (thio-DMAA), and thio-DMA) were measured in spot urine samples prior to seaweed consumption, and in 24-hour urine samples while consuming seaweed. Commercial products made from whole seaweed had substantial concentrations of arsenic (12-84 µg/g), dominated by arsenosugars. Intact arsenosugars along with DMA, thio-DMAA, thio-DMAE all increased in urine after ingesting each type of seaweed, and varied between seaweed types and between individuals. Only trace levels of the known toxic metabolite, thio-DMA, were observed, across individuals. Thio-DMAE and thio-DMAA are unique products of arsenosugar breakdown, thus assessment of these compounds may help to identify dietary intake of arsenic from seaweed from other exposure pathways.

  5. Anthropogenic influences on groundwater arsenic concentrations in Bangladesh

    Science.gov (United States)

    Neumann, Rebecca B.; Ashfaque, Khandaker N.; Badruzzaman, A. B. M.; Ashraf Ali, M.; Shoemaker, Julie K.; Harvey, Charles F.

    2010-01-01

    The origin of dissolved arsenic in the Ganges Delta has puzzled researchers ever since the report of widespread arsenic poisoning two decades ago. Today, microbially mediated oxidation of organic carbon is thought to drive the geochemical transformations that release arsenic from sediments, but the source of the organic carbon that fuels these processes remains controversial. At a typical site in Bangladesh, where groundwater-irrigated rice fields and constructed ponds are the main sources of groundwater recharge, we combine hydrologic and biogeochemical analyses to trace the origin of contaminated groundwater. Incubation experiments indicate that recharge from ponds contains biologically degradable organic carbon, whereas recharge from rice fields contains mainly recalcitrant organic carbon. Chemical and isotopic indicators as well as groundwater simulations suggest that recharge from ponds carries this degradable organic carbon into the shallow aquifer, and that groundwater flow, drawn by irrigation pumping, transports pond water to the depth where dissolved arsenic concentrations are greatest. Results also indicate that arsenic concentrations are low in groundwater originating from rice fields. Furthermore, solute composition in arsenic-contaminated water is consistent with that predicted using geochemical models of pond-water-aquifer-sediment interactions. We therefore suggest that the construction of ponds has influenced aquifer biogeochemistry, and that patterns of arsenic contamination in the shallow aquifer result from variations in the source of water, and the complex three-dimensional patterns of groundwater flow.

  6. 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.

  7. 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

  8. Nitarsone, Inorganic Arsenic, and Other Arsenic Species in Turkey Meat: Exposure and Risk Assessment Based on a 2014 U.S. Market Basket Sample

    National Research Council Canada - National Science Library

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

    ...: We characterized the impact of nitarsone use on arsenic species in turkey meat and arsenic exposures among turkey consumers, and we estimated cancer risk increases from consuming turkey treated...

  9. A prospective study of respiratory symptoms associated with chronic arsenic exposure in Bangladesh: findings from the Health Effects of Arsenic Longitudinal Study (HEALS)

    National Research Council Canada - National Science Library

    Parvez, Faruque; Chen, Yu; Brandt-Rauf, Paul W; Slavkovich, Vesna; Islam, Tariqul; Ahmed, Alauddin; Argos, Maria; Hassan, Rabiul; Yunus, Mahbub; Haque, Syed E; Balac, Olgica; Graziano, Joseph H; Ahsan, Habibul

    2010-01-01

    A prospective cohort study was conducted to evaluate the effect of arsenic (As) exposure from drinking water on respiratory symptoms using data from the Health Effects of Arsenic Exposure Longitudinal Study (HEALS...

  10. Distribution and risk assessment of metals and arsenic contamination in man-made ditch sediments with different land use types.

    Science.gov (United States)

    Nsenga Kumwimba, Mathieu; Zhu, Bo; Wang, Tao; Muyembe, Diana Kavidia

    2016-12-01

    Ditches are subjected to a large input of nutrients, trace metals, and arsenic and the enhancement of sedimentation due to human activities. However, the influence of different types of land uses on the distribution and associated environmental risk of metals and arsenic in the Red purple Sichuan Basin remains largely unclear, which is needed for water management. This study was carried out to characterize metal/metalloid status in ditch sediments from different land uses. A total of 68 surface sediment samples (0-5 cm) were collected from open ditches distributed in different land use types, i.e., cultivated ditches (CD), barren land ditches (BLD), roadside ditches (RSD), and residential ditches (RD), within the Sichuan Basin. Mean concentrations of Cr, Ni, Cu, Zn, Cd, Pb, and Mn in both RD and RSD were above the soil background values of Sichuan Basin, but Cd in ditch sediments of the basin posed considerable ecological risk to the environment. Overall, metals/metalloid (except Pb) decreased in the following order of RD > RSD > BLD > CD. Of the different land use types in the hilly region, residential and roadside land uses were likely to adverse effects on aquatic life. Multivariate statistical analysis showed that Mn, As, Cu, Ni, Zn, Fe, and Al were mainly influenced by natural weathering (erosion), while Pb might come from heavy vehicular traffic. The degree of contamination (Md), enrichment factor (EF), and the geo-accumulation index (Igeo) showed that Cd causes strong sediment pollution in the basin. Sediment quality guidelines SQG-Q values displayed that metals and arsenic created medium-low potential of adverse biological effects. These results provide baseline information on the metals and arsenic pollution in the Sichuan Basin. Awareness of land use type contributions to metals and arsenic requires that these man-made ditches be considered for their mitigation of pollutants in this region.

  11. Arsenite and ferrous iron oxidation linked to chemolithotrophic denitrification for the immobilization of arsenic in anoxic environments

    Science.gov (United States)

    Sun, W.; Sierra-Alvarez, R.; Milner, L.; Oremland, R.; Field, J.A.

    2009-01-01

    The objective of this study was to explore a bioremediation strategy based on injecting NO3- to support the anoxic oxidation of ferrous iron (Fe(II)) and arsenite (As(III)) in the subsurface as a means to immobilize As in the form of arsenate (As(V)) adsorbed onto biogenic ferric (Fe(III)) (hydr)oxides. Continuous flows and filled columns were used to simulate a natural anaerobic groundwater and sediment system with co-occurring As(III) and Fe(II) in the presence (column SF1) or absence (column SF2) of nitrate, respectively. During operation for 250 days, the average influent arsenic concentration of 567 ??g L-1 was reduced to 10.6 (??9.6) ??g L-1 in the effluent of column SF1. The cumulative removal of Fe(II) and As(III) in SF1 was 6.5 to 10-fold higher than that in SF2. Extraction and measurement of the mass of iron and arsenic immobilized on the sand packing of the columns were close to the iron and arsenic removed from the aqueous phase during column operation. The dominant speciation of the immobilized iron and arsenic was Fe(III) and As(V) in SF1, compared with Fe(II) and As(III) in SF2. The speciation was confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The results indicate that microbial oxidation of As(III) and Fe(II) linked to denitrification resulted in the enhanced immobilization of aqueous arsenic in anaerobic environments by forming Fe(III) (hydr)oxide coated sands with adsorbed As(V). ?? 2009 American Chemical Society.

  12. Arsenic load in rice ecosystem and its mitigation through deficit irrigation.

    Science.gov (United States)

    Mukherjee, Arkabanee; Kundu, M; Basu, B; Sinha, B; Chatterjee, M; Bairagya, M Das; Singh, U K; Sarkar, S

    2017-07-15

    Rice the staple food is a notable intake source of arsenic to the rural population of eastern India through food-chain. A field survey was carried out to study the variation of arsenic load in different parts of rice genotype Shatabdi (most popular genotype of the region) exposed to varying level of arsenic present in the irrigation water and soil. As irrigation is the primary source of arsenic contamination, a study was conducted to assess arsenic load in rice ecosystem under deficit irrigation practices like intermittent ponding (IP), saturation (SAT) and aerobic (AER) imposed during stress allowable stage (16-40 days after transplanting) of the crop (genotype Shatabdi). Present survey showed that arsenic content in water and soil influenced the arsenic load of rice grain. Variation in arsenic among different water and soil samples influenced grain arsenic load to the maximum extent followed by straw. Deviation in root arsenic load due to variation in water and soil arsenic content was lowest. Arsenic concentration of grain is strongly related to the arsenic content of both irrigation water and soil. However, water has 10% higher impact on grain arsenic load over soil. Translocation of arsenic from root to shoot decreased with the increase in arsenic content of water. Imposition of saturated and aerobic environment reduced both yield and grain arsenic load. In contrast under IP a marked decrease in grain arsenic content recorded with insignificant reduction in yield. Deficit irrigation resulted in significant reduction (17.6-25%) in arsenic content of polished rice and the values were lower than that of the toxic level (<0.2 mg kg-1). In contrast the decrease in yield was to the tune of 0.9% under IP regime over CP. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Groundwater arsenic contamination and its health effects in India

    Science.gov (United States)

    Chakraborti, Dipankar; Rahman, Mohammad Mahmudur; Das, Bhaskar; Chatterjee, Amit; Das, Dipankar; Nayak, Biswajit; Pal, Arup; Chowdhury, Uttam Kumar; Ahmed, Sad; Biswas, Bhajan Kumar; Sengupta, Mrinal Kumar; Hossain, Md. Amir; Samanta, Gautam; Roy, M. M.; Dutta, Rathindra Nath; Saha, Khitish Chandra; Mukherjee, Subhas Chandra; Pati, Shyamapada; Kar, Probir Bijoy; Mukherjee, Adreesh; Kumar, Manoj

    2017-06-01

    During a 28-year field survey in India (1988-2016), groundwater arsenic contamination and its health effects were registered in the states of West Bengal, Jharkhand, Bihar and Uttar Pradesh in the Ganga River flood plain, and the states of Assam and Manipur in the flood plain of Brahamaputra and Imphal rivers. Groundwater of Rajnandgaon village in Chhattisgarh state, which is not in a flood plain, is also arsenic contaminated. More than 170,000 tubewell water samples from the affected states were analyzed and half of the samples had arsenic >10 μg/L (maximum concentration 3,700 μg/L). Chronic exposure to arsenic through drinking water causes various health problems, like dermal, neurological, reproductive and pregnancy effects, cardiovascular effects, diabetes mellitus, diseases of the respiratory and gastrointestinal systems, and cancers, typically involving the skin, lungs, liver, bladder, etc. About 4.5% of the 8,000 children from arsenic-affected villages of affected states were registered with mild to moderate arsenical skin lesions. In the preliminary survey, more than 10,000 patients were registered with different types of arsenic-related signs and symptoms, out of more than 100,000 people screened from affected states. Elevated levels of arsenic were also found in biological samples (urine, hair, nails) of the people living in affected states. The study reveals that the population who had severe arsenical skin lesions may suffer from multiple Bowens/cancers in the long term. Some unusual symptoms, such as burning sensation, skin itching and watering of eyes in the presence of sun light, were also noticed in arsenicosis patients.

  14. Role of adsorbed arsenic and structural aluminum on Fe(II) retention and transformation of ferrihydrite (Invited)

    Science.gov (United States)

    Sharma, R.; Masue-Slowey, Y.; Fendorf, S. E.

    2009-12-01

    Arsenic is a wide-spread toxin contaminating water from both natural (as in the case of South and Southeast Asia) and anthropogenic sources. Its high affinity for soil solids helps to regulate the deleterious impacts of this toxic element on ecosystem and human health. Iron (hydr)oxides are of particular importance in controlling dissolved concentrations of arsenic, making the behavior of these substrates crucial to understanding the transport and ultimate fate of arsenic. Ferrihydrite is one of the most active forms of Fe (hydr)oxides, and aluminum-substituted ferrihydrite is a common form of this phase in soils and sediment. Sorption of Fe(II) catalyzes the transformation of the thermodynamically unstable ferrihydrite to more thermodynamically stable Fe (hydr)oxides. Although the process of ferrihydrite transformation has been extensively studied, the role of structural aluminum and adsorbed arsenic on the Fe(II)-catalyzed transformation of ferrihydrite is unknown. Hence, the objective of this study was to compare how ferrihydrite and aluminum-substituted ferrihydrite differ in their retention of Fe(II) and the resulting transformation rates and products in the presence and absence of arsenic. Sand coated with ferrihydrite and aluminum-ferrihydrite (with and without adsorbed arsenic) was packed into columns and flow of circumneutral groundwater solution containing 0.2 to 4 mM Fe(II) was initiated. Breakthrough of Fe(II) was monitored using the ferrozine colorimetric assay to determine Fe(II) retention in the solid phase. The solid phase was characterized using Fe K-edge X-ray absorption spectroscopy and scanning electron microscopy. Structural aluminum limits Fe(II) sorption, and, as a consequence, the extent of the aluminum-substituted ferrihydrite transformation is much less than that of ferrihydrite. Adsorbed As further decreases Fe(II) retention on aluminum-ferrihydrite. In contrast, Fe(II) retention on ferrihydrite is enhanced in the presence of arsenic due

  15. Removal of arsenic from Janghang smelter site and energy crops-grown soil with soil washing using magnetic iron oxide

    Science.gov (United States)

    Han, Jaemaro; Zhao, Xin; Lee, Jong Keun; Kim, Jae Young

    2014-05-01

    Arsenic compounds are considered carcinogen and easily enter drinking water supplies with their natural abundance. US Environmental Protection Agency is finalizing a regulation to reduce the public health risks from arsenic in drinking water by revising the current drinking water standard for arsenic from 50 ppb to 10 ppb in 2001 (USEPA, 2001). Therefore, soil remediation is also growing field to prevent contamination of groundwater as well as crop cultivation. Soil washing is adjusted as ex-situ soil remediation technique which reduces volume of the contaminated soil. The technique is composed of physical separation and chemical extraction to extract target metal contamination in the soil. Chemical extraction methods have been developed solubilizing contaminants containing reagents such as acids or chelating agents. And acid extraction is proven as the most commonly used technology to treat heavy metals in soil, sediment, and sludge (FRTR, 2007). Due to the unique physical and chemical properties, magnetic iron oxide have been used in diverse areas including information technology and biomedicine. Magnetic iron oxides also can be used as adsorbent to heavy metal enhancing removal efficiency of arsenic concentration. In this study, magnetite is used as the washing agent with acid extraction condition so that the injected oxide can be separated by magnetic field. Soil samples were collected from three separate areas in the Janghang smelter site and energy crops-grown soil to have synergy effect with phytoremediation. Each sample was air-dried and sieved (2mm). Soil washing condition was adjusted on pH in the range of 0-12 with hydrogen chloride and sodium hydroxide. After performing soil washing procedure, arsenic-extracted samples were analyzed for arsenic concentration by inductively coupled plasma optical emission spectrometer (ICP-OES). All the soils have exceeded worrisome level of soil contamination for region 1 (25mg/kg) so the soil remediation techniques are

  16. Arsenic-rich acid mine water with extreme arsenic concentration: mineralogy, geochemistry, microbiology, and environmental implications.

    Science.gov (United States)

    Majzlan, Juraj; Plášil, Jakub; Škoda, Radek; Gescher, Johannes; Kögler, Felix; Rusznyak, Anna; Küsel, Kirsten; Neu, Thomas R; Mangold, Stefan; Rothe, Jörg

    2014-12-02

    Extremely arsenic-rich acid mine waters have developed by weathering of native arsenic in a sulfide-poor environment on the 10th level of the Svornost mine in Jáchymov (Czech Republic). Arsenic rapidly oxidizes to arsenolite (As2O3), and there are droplets of liquid on the arsenolite crust with high As concentration (80,000-130,000 mg·L(-1)), pH close to 0, and density of 1.65 g·cm(-1). According to the X-ray absorption spectroscopy on the frozen droplets, most of the arsenic is As(III) and iron is fully oxidized to Fe(III). The EXAFS spectra on the As K edge can be interpreted in terms of arsenic polymerization in the aqueous solution. The secondary mineral that precipitates in the droplets is kaatialaite [Fe(3+)(H2AsO4)3·5H2O]. Other unusual minerals associated with the arsenic lens are běhounekite [U(4+)(SO4)2·4H2O], štěpite [U(4+)(AsO3OH)2·4H2O], vysokýite [U(4+)[AsO2(OH)2]4·4H2O], and an unnamed phase (H3O)(+)2(UO2)2(AsO4)2·nH2O. The extremely low cell densities and low microbial biomass have led to insufficient amounts of DNA for downstream polymerase chain reaction amplification and clone library construction. We were able to isolate microorganisms on oligotrophic media with pH ∼ 1.5 supplemented with up to 30 mM As(III). These microorganisms were adapted to highly oligotrophic conditions which disabled long-term culturing under laboratory conditions. The extreme conditions make this environment unfavorable for intensive microbial colonization, but our first results show that certain microorganisms can adapt even to these harsh conditions.

  17. Arsenic Sequestration By Sorption Processes in High-Iron Sediments

    Energy Technology Data Exchange (ETDEWEB)

    Root, R.A.; Dixit, S.; Campbell, K.M.; Jew, A.D.; Hering, J.G.; O' Day, P.A.

    2009-06-04

    High-iron sediments in North Haiwee Reservoir (Olancha, CA), resulting from water treatment for removal of elevated dissolved arsenic in the Los Angeles Aqueduct system, were studied to examine arsenic partitioning between solid phases and porewaters undergoing shallow burial. To reduce arsenic in drinking water supplies, ferric chloride and a cationic polymer coagulant are added to the aqueduct upstream of Haiwee Reservoir, forming an iron-rich floc that scavenges arsenic from the water. Analysis by synchrotron X-ray absorption spectroscopy (XAS) showed that the aqueduct precipitate is an amorphous hydrous ferric oxide (HFO) similar to ferrihydrite, and that arsenic is associated with the floc as adsorbed and/or coprecipitated As(V). Arsenic-rich floc and sediments are deposited along the inlet channel as aqueduct waters enter the reservoir. Sediment core samples were collected in two consecutive years from the edge of the reservoir along the inlet channel using 30- or 90-cm push cores. Cores were analyzed for total and extractable arsenic and iron concentrations. Arsenic and iron speciation and mineralogy in sediments were examined at selected depths by synchrotron XAS and X-ray diffraction (XRD). Sediment-porewater measurements were made adjacent to the core sample sites using polyacrylamide gel probe samplers. Results showed that sediment As(V) is reduced to As(III) in all cores at or near the sediment-water interface (0--4 cm), and only As(III) was observed in deeper sediments. Analyses of EXAFS spectra indicated that arsenic is present in the sediments mostly as a bidentate-binuclear, inner-sphere sorption complex with local atomic geometries similar to those found in laboratory studies. Below about 10 cm depth, XAS indicated that the HFO floc had been reduced to a mixed Fe(II, III) solid with a local structure similar to that of synthetic green rust (GR) but with a slightly contracted average interatomic Fe-Fe distance in the hydroxide layer. There was no

  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. An insight of environmental contamination of arsenic on animal health

    OpenAIRE

    Paramita Mandal

    2017-01-01

    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 canc...

  20. Arsenic, GSTO2 Asp142 polymorphism, health and treatment

    OpenAIRE

    Masoudi, Mohammad; Saadat, Mostafa

    2008-01-01

    Arsenic is a natural metallic element found in low concentrations in virtually every part of the environment, including waters and foods. The ingestion of arsenic by humans can cause a variety of disorders. Glutathione S-transferase omega (GSTO) is a member of phase II xenobiotic metabolizing enzymes. GSTO2 (a member of GST omega) participates in detoxification of inorganic arsenic. In human, the A>G transition at nucleotide position 424 of GSTO2 was reported. This variation causes an Asn142A...

  1. Arsenic in industrial waste water from copper production technological process

    Directory of Open Access Journals (Sweden)

    Biljana Jovanović

    2013-12-01

    Full Text Available Investigation of arsenic in industrial waste water is of a great importance for environment. Discharge of untreated waste water from a copper production process results in serious pollution of surface water, which directly affects flora and fauna, as well as humans. There is a need for efficient and environmentally acceptable treament of waste waters containing heavy metals and arsenic. The paper presents an analyisis of the waste water from The Copper Smelter which is discharged into the Bor river. The expected arsenic content in treated waste water after using HDS procedure is also presented.

  2. Bacterial respiration of arsenic and selenium

    Science.gov (United States)

    Stolz, J.F.; Oremland, R.S.

    1999-01-01

    Oxyanions of arsenic and selenium can be used in microbial anaerobic respiration as terminal electron acceptors. The detection of arsenate and selenate respiring bacteria in numerous pristine and contaminated environments and their rapid appearance in enrichment culture suggest that they are widespread and metabolically active in nature. Although the bacterial species that have been isolated and characterized are still few in number, they are scattered throughout the bacterial domain and include Gram- positive bacteria, beta, gamma and epsilon Proteobacteria and the sole member of a deeply branching lineage of the bacteria, Chrysiogenes arsenatus. The oxidation of a number of organic substrates (i.e. acetate, lactate, pyruvate, glycerol, ethanol) or hydrogen can be coupled to the reduction of arsenate and selenate, but the actual donor used varies from species to species. Both periplasmic and membrane-associated arsenate and selenate reductases have been characterized. Although the number of subunits and molecular masses differs, they all contain molybdenum. The extent of the environmental impact on the transformation and mobilization of arsenic and selenium by microbial dissimilatory processes is only now being fully appreciated.

  3. Study on arsenic removal process from water

    Directory of Open Access Journals (Sweden)

    B Bayarmaa

    2014-09-01

    Full Text Available In this study a novel adsorbent, iron oxide, is used for As (V or As (III removal. Some ferric oxides have been reported to be effective for arsenic removal. Ferric oxides powder is a good adsorbent material since it’s has magnetic properties and a good adsorption capacity. The main purpose of this study has been focused on to study the relationship between adsorption capacity (ability, performance and the surface characteristics of the ferric oxide. Prepared sample’s capacity was evaluated. The value was 26.1-67.4 mg/g for As (V and 20.5-47.8 mg/g for As (III. pH dependence was evaluated and when pH increasing, adsorption capacity was decreased. The kinetic was evaluated and about 12 hours reached equilibrium and a capacity of 49 mg/g for As (V and 42 mg/g for As(III was gained. The kinetic constants for arsenic adsorption on the ferrihydrite adsorbent’s were fitted.DOI: http://dx.doi.org/10.5564/mjc.v12i0.172 Mongolian Journal of Chemistry Vol.12 2011: 53-55

  4. Arsenic chemistry and remediation in Hawaiian soils.

    Science.gov (United States)

    Hue, Nguyen V

    2013-01-01

    Past use of arsenical pesticides has resulted in elevated levels of arsenic (As) in some Hawaiian soils. Total As concentrations of 20-100 mg/kg are not uncommon, and can exceed 900 mg/kg in some lands formerly planted with sugarcane. With high contents of amorphous aluminosilicates and iron oxides in many Hawaii's volcanic ash-derived Andisols, a high proportion (25-30%) of soil As was associated with either these mineral phases or with organic matter. Less than 1% of the total As was water soluble or exchangeable. Furthermore, the soils can sorb As strongly: the addition of 1000 mg/kg as As (+5) resulted in only between 0.03 and 0.30 mg/L As in soil solution. In contrast, soils having more crystalline minerals (e.g., Oxisols) sorb less As and thus often contain less As. Phosphate fertilization increases As bioaccessibility, whereas the addition of Fe(OH)3 decreases it. Brake fern (Pteris vittata L.) can be used to remove some soil As. Concentrations of As in fronds varied on average from 60 mg/kg when grown on a low-As Oxisol to 350 mg/kg when grown on a high-As Andisol. Ratios of leaf As to CaCl2-extractable soil As were 12 and 222 for the Oxisol and Andisol, respectively.

  5. Preliminary study on the mode of occurrence of arsenic in high arsenic coals from southwest Guizhou Province

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Z.H.; Zheng, B.S.; Zhang, J.; Belkin, H.E.; Finkelman, R.B.; Zhao, F.H.; Zhao, D.X.; Zhou, Y.S.; Chen, C.G. [Chinese Academy of Sciences, Guiyang (China). Inst. of Geochemistry

    1999-12-01

    Coal samples from high arsenic coal areas have been analyzed by electron microprobe analyzer (EMPA), scanning electron microscopy with an energy dispersive X-ray analyzer (SEM-EDX), X-ray difffraction analysis (XRD), low temperature ashing (LTA), transmission electron microscopy (TEM), X-ray absorption fine structure (ZAFS), instrument neutron activation analysis (INAA) and wet chemical analys