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Sample records for radioactive elements arsenic

  1. TABLE OF RADIOACTIVE ELEMENTS.

    SciTech Connect

    HOLDEN,N.E.

    2001-06-29

    For those chemical elements which have no stable nuclides with a terrestrial isotopic composition, the data on radioactive half-lives and relative atomic masses for the nuclides of interest and importance have been evaluated and the recommended values and uncertainties are listed.

  2. TABLE OF RADIOACTIVE ELEMENTS.

    SciTech Connect

    HOLDEN,N.E.

    2001-06-29

    For those chemical elements which have no stable nuclides with a terrestrial isotopic composition, the data on radioactive half-lives and relative atomic masses for the nuclides of interest and importance have been evaluated and the recommended values and uncertainties are listed.

  3. Radioactive elements in stellar atmospheres

    SciTech Connect

    Gopka, Vira; Yushchenko, Alexander; Goriely, Stephane; Shavrina, Angelina; Kang, Young Woon

    2006-07-12

    The identification of lines of radioactive elements (Tc, Pm and elements with 83radioactive decay of Th and U in the upper levels of stellar atmospheres, contamination of stellar atmosphere by recent SN explosion, and spallation reactions.

  4. Table of radioactive elements

    SciTech Connect

    Holden, N.E.

    1985-01-01

    As has been the custom in the past, the Commission publishes a table of relative atomic masses and halflives of selected radionuclides. The information contained in this table will enable the user to calculate the atomic weight for radioactive materials with a variety of isotopic compositions. The atomic masses have been taken from the 1984 Atomic Mass Table. Some of the halflives have already been documented.

  5. Radioactive dating of the elements

    NASA Technical Reports Server (NTRS)

    Cowan, John J.; Thielemann, Friedrich-Karl; Truran, James W.

    1991-01-01

    The extent to which an accurate determination of the age of the Galaxy, and thus a lower bound on the age of the universe, can be obtained from radioactive dating is discussed. Emphasis is given to the use of the long-lived radioactive nuclei Re-187, Th-232, U-238, and U-235. The nature of the production sites of these and other potential Galactic chronometers is examined along with their production ratios. Age determinations from models of nucleocosmochronology are reviewed and compared with age determination from stellar sources and age constraints form cosmological considerations.

  6. Radioactive dating of the elements

    NASA Technical Reports Server (NTRS)

    Cowan, John J.; Thielemann, Friedrich-Karl; Truran, James W.

    1991-01-01

    The extent to which an accurate determination of the age of the Galaxy, and thus a lower bound on the age of the universe, can be obtained from radioactive dating is discussed. Emphasis is given to the use of the long-lived radioactive nuclei Re-187, Th-232, U-238, and U-235. The nature of the production sites of these and other potential Galactic chronometers is examined along with their production ratios. Age determinations from models of nucleocosmochronology are reviewed and compared with age determination from stellar sources and age constraints form cosmological considerations.

  7. Radioactive Elements in Coal and Fly Ash: Abundance, Forms, and Environmental Significance

    USGS Publications Warehouse

    Zielinski, Robert A.; Finkelman, Robert B.

    1997-01-01

    Coal is largely composed of organic matter, but it is the inorganic matter in coal—minerals and trace elements— that have been cited as possible causes of health, environmental, and technological problems associated with the use of coal. Some trace elements in coal are naturally radioactive. These radioactive elements include uranium (U), thorium (Th), and their numerous decay products, including radium (Ra) and radon (Rn). Although these elements are less chemically toxic than other coal constituents such as arsenic, selenium, or mercury, questions have been raised concerning possible risk from radiation. In order to accurately address these questions and to predict the mobility of radioactive elements during the coal fuel-cycle, it is important to determine the concentration, distribution, and form of radioactive elements in coal and fly ash.

  8. RADIOACTIVE CHEMICAL ELEMENTS IN THE ATOMIC TABLE.

    SciTech Connect

    HOLDEN, N.E.

    2005-08-13

    In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (longest-lived) known isotope as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular elements has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass number to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of ''these constants'' for use in chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was most stable, i.e., it had the longest known half-life. In their 1973 report, the Commission noted that the users of the Atomic Weights Table were dissatisfied with the omission of values in the Table for some elements and it was decided to reintroduce the mass number for elements. In their 1983 report, the Commission decided that radioactive elements were considered to lack a characteristic terrestrial isotopic composition, from which an atomic weight value could be calculated to

  9. DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

    SciTech Connect

    NA

    2004-11-22

    The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this modeling activity is to predict dissolved concentrations or solubility limits for 14 elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) important to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are in the form of tabulated functions with pH and log (line integral) CO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. The output data from this report are fundamental inputs for Total System Performance Assessment for the License Application (TSPA-LA) to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for all of the actinides. These models cover broad ranges of environmental conditions so that they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or otherwise addressed.

  10. DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

    SciTech Connect

    P. Bernot

    2005-07-13

    The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this activity is to predict dissolved concentrations or solubility limits for elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) relevant to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are provided in the form of tabulated functions with pH and log fCO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. Even though selection of an appropriate set of radionuclides documented in Radionuclide Screening (BSC 2002 [DIRS 160059]) includes actinium, transport of Ac is not modeled in the total system performance assessment for the license application (TSPA-LA) model because of its extremely short half-life. Actinium dose is calculated in the TSPA-LA by assuming secular equilibrium with {sup 231}Pa (Section 6.10); therefore, Ac is not analyzed in this report. The output data from this report are fundamental inputs for TSPA-LA used to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for the actinides discussed in this report. These models cover broad ranges of environmental conditions so they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or

  11. Dissolved Concentration Limits of Radioactive Elements

    SciTech Connect

    Y. Chen; E.R. Thomas; F.J. Pearson; P.L. Cloke; T.L. Steinborn; P.V. Brady

    2003-06-20

    The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of radioactive elements under possible repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, and measurements made in laboratory experiments and field work. The scope of this modeling activity is to predict dissolved concentrations or solubility limits for 14 radioactive elements (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium), which are important to calculated dose. Model outputs are mainly in the form of look-up tables plus one or more uncertainty terms. The rest are either in the form of distributions or single values. The results of this analysis are fundamental inputs for total system performance assessment to constrain the release of these elements from waste packages and the engineered barrier system. Solubilities of plutonium, neptunium, uranium, americium, actinium, thorium, protactinium, lead, and radium have been re-evaluated using the newly updated thermodynamic database (Data0.ymp.R2). For all of the actinides, identical modeling approaches and consistent environmental conditions were used to develop solubility models in this revision. These models cover broad ranges of environmental conditions so that they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, activity coefficients, and selection of solubility controlling phase have been quantified or otherwise addressed. Moreover, a new blended plutonium solubility model has been developed in this revision, which gives a mean solubility that is three orders of magnitude lower than the plutonium solubility model used for the Total System Performance Assessment for the Site Recommendation. Two alternative neptunium solubility models have also been

  12. Microbial transformation of elements: the case of arsenic and selenium

    USGS Publications Warehouse

    Stolz, J.; Basu, P.; Oremland, R.

    2002-01-01

    Microbial activity is responsible for the transformation of at least one third of the elements in the periodic table. These transformations are the result of assimilatory, dissimilatory, or detoxification processes and form the cornerstones of many biogeochemical cycles. Arsenic and selenium are two elements whose roles in microbial ecology have only recently been recognized. Known as "essential toxins", they are required in trace amounts for growth and metabolism but are toxic at elevated concentrations. Arsenic is used as an osmolite in some marine organisms while selenium is required as selenocysteine (i.e. the twenty-first amino acid) or as a ligand to metal in some enzymes (e.g. FeNiSe hydrogenase). Arsenic resistance involves a small-molecular-weight arsenate reductase (ArsC). The use of arsenic and selenium oxyanions for energy is widespread in prokaryotes with representative organisms from the Crenarchaeota, thermophilic bacteria, low and high G+C gram-positive bacteria, and Proteobacteria. Recent studies have shown that both elements are actively cycled and play a significant role in carbon mineralization in certain environments. The occurrence of multiple mechanisms involving different enzymes for arsenic and selenium transformation indicates several different evolutionary pathways (e.g. convergence and lateral gene transfer) and underscores the environmental significance and selective impact in microbial evolution of these two elements.

  13. Microbial transformation of elements: the case of arsenic and selenium.

    PubMed

    Stolz, J F; Basu, P; Oremland, R S

    2002-12-01

    Microbial activity is responsible for the transformation of at least one third of the elements in the periodic table. These transformations are the result of assimilatory, dissimilatory, or detoxification processes and form the cornerstones of many biogeochemical cycles. Arsenic and selenium are two elements whose roles in microbial ecology have only recently been recognized. Known as "essential toxins", they are required in trace amounts for growth and metabolism but are toxic at elevated concentrations. Arsenic is used as an osmolite in some marine organisms while selenium is required as selenocysteine (i.e. the twenty-first amino acid) or as a ligand to metal in some enzymes (e.g. FeNiSe hydrogenase). Arsenic resistance involves a small-molecular-weight arsenate reductase (ArsC). The use of arsenic and selenium oxyanions for energy is widespread in prokaryotes with representative organisms from the Crenarchaeota, thermophilic bacteria, low and high G+C gram-positive bacteria, and Proteobacteria. Recent studies have shown that both elements are actively cycled and play a significant role in carbon mineralization in certain environments. The occurrence of multiple mechanisms involving different enzymes for arsenic and selenium transformation indicates several different evolutionary pathways (e.g. convergence and lateral gene transfer) and underscores the environmental significance and selective impact in microbial evolution of these two elements.

  14. Prompt gamma neutron activation analysis of toxic elements in radioactive waste packages.

    PubMed

    Ma, J-L; Carasco, C; Perot, B; Mauerhofer, E; Kettler, J; Havenith, A

    2012-07-01

    The French Alternative Energies and Atomic Energy Commission (CEA) and National Radioactive Waste Management Agency (ANDRA) are conducting an R&D program to improve the characterization of long-lived and medium activity (LL-MA) radioactive waste packages. In particular, the amount of toxic elements present in radioactive waste packages must be assessed before they can be accepted in repository facilities in order to avoid pollution of underground water reserves. To this aim, the Nuclear Measurement Laboratory of CEA-Cadarache has started to study the performances of Prompt Gamma Neutron Activation Analysis (PGNAA) for elements showing large capture cross sections such as mercury, cadmium, boron, and chromium. This paper reports a comparison between Monte Carlo calculations performed with the MCNPX computer code using the ENDF/B-VII.0 library and experimental gamma rays measured in the REGAIN PGNAA cell with small samples of nickel, lead, cadmium, arsenic, antimony, chromium, magnesium, zinc, boron, and lithium to verify the validity of a numerical model and gamma-ray production data. The measurement of a ∼20kg test sample of concrete containing toxic elements has also been performed, in collaboration with Forschungszentrum Jülich, to validate the model in view of future performance studies for dense and large LL-MA waste packages. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Inorganic arsenic and trace elements in Ghanaian grain staples.

    PubMed

    Adomako, Eureka E; Williams, Paul N; Deacon, Claire; Meharg, Andrew A

    2011-10-01

    A total of 549 samples of rice, maize, wheat, sorghum and millet were obtained from markets in Ghana, the EU, US and Asia. Analysis of the samples, originating from 21 countries in 5 continents, helped to establish global mean trace element concentrations in grains; thus placing the Ghanaian data within a global context. Ghanaian rice was generally low in potentially toxic elements, but high in essential nutrient elements. Arsenic concentrations in rice from US (0.22 mg/kg) and Thailand (0.15 mg/kg) were higher than in Ghanaian rice (0.11 mg/kg). Percentage inorganic arsenic content of the latter (83%) was, however, higher than for US (42%) and Thai rice (67%). Total arsenic concentration in Ghanaian maize, sorghum and millet samples (0.01 mg/kg) was an order of magnitude lower than in Ghanaian rice, indicating that a shift from rice-centric to multigrain diets could help reduce health risks posed by dietary exposure to inorganic As.

  16. Radioactive Elements in Soils of Siberia (Russia)

    NASA Astrophysics Data System (ADS)

    Baranovskaya, N. V.; Rikhvanov, L. P.; Matveenko, I. N.; Strakhovenko, V. D.; Malikova, I. N.; Shcherbakov, B. L.; Sukhorukov, F. V.; Aturova, V. P.

    2012-04-01

    The Center of State Sanitary and Epidemiological Surveillance Department in Krasnoyarsk Territory, Krasnoyarsk In the course of long-term research a great deal of information on the content of natural and artificial radionuclides in soils of the Siberian regions has been obtained and summarized (Altai and Krasnoyarsk Territories, Altai Republic, Buryatia, Yakutia, Khakassia, Irkutsk, Novosibirsk, Tomsk Oblasts and a number of other Siberian regions). The content level of U(Ra), Th and K in soil of studied areas is within the range of values obtained for soil of other areas of Russia and the world and defined, first of all, by radioactivity of parent rocks. The authors have studied the total level of specific activity for 137Cs most completely in soils of different Siberian regions. The maximum density of such sites with global fallouts (nuclear air explosions in Novaya Zemlya, Lop Nor, Semipalatinsk etc.) is typical for the areas of Altai Territory and Buryatia Republic. Elevated level of radiocesium (to 1000 and more than Bq/kg) is characteristic for the sites adjacent to the area of NFP (Seversk, Zheleznogorsk). Our data obtained in determination of plutonium in soils of different Siberian regions excess remarkably its background accepted for Siberia. Particularly high accumulation levels of Pu in soil were observed in the zones of NFP operation (Seversk, Tomsk Oblast; Zheleznogorsk, Krasnoyarsk Territory, in the sites of accidents fallouts at underground nuclear explosions in Sakha Republic (Yakutia). Abnormally high ratio of 238Pu/239,240Pu in soils of Sakha republic, Aginsk Buryatia Autonomous District, Krasnoyarsk Territory has engaged our attention.

  17. STATUS OF RADIOACTIVE ELEMENTS IN THE ATOMIC WEIGHTS TABLE.

    SciTech Connect

    HOLDEN,N.E.

    2003-08-08

    During discussions within the Inorganic Chemistry Division Committee, that dealt with the Periodic Table of the Chemical Elements and the official IUPAC position on its presentation, the following question was raised. When the various chemical elements are presented, each with their appropriate atomic weight value, how should the radioactive elements be presented? The Atomic Weights Commission has treated this question in a number of different ways during the past century, almost in a random manner. This report reviews the position that the Commission has taken as a function of time, as a prelude to a discussion in Ottawa about how the Commission should resolve this question for the future.

  18. Radioactive Elements in the Standard Atomic Weights Table.

    SciTech Connect

    Holden,N.E.

    2007-08-04

    In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (or longest-lived) known isotope as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular element has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of 'these constants' for use in various chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was the most stable, i.e., the one with the longest known half-life. In their 1973 Report, the Commission noted that the users of the main Table of Atomic Weights were dissatisfied with the omission of values for some elements in that Table and it was decided to reintroduce the mass number for the radioactive elements into the main Table. In their 1983 Report, the Commission decided that radioactive elements were considered to lack a characteristic terrestrial isotopic composition

  19. Low molecular weight thiols in arsenic hyperaccumulator Pteris vittata upon exposure to arsenic and other trace elements.

    PubMed

    Cai, Yong; Su, Jinhui; Ma, Lena Q

    2004-05-01

    Low molecular weight thiol-containing compounds have been reported to play an important role in metal detoxification and accumulation in some higher plants. The formation of these low molecular weight thiols in the recently discovered arsenic hyperaccumulator, Chinese Brake fern (Pteris vittata) upon exposure to arsenic and other trace metals was investigated. In addition to cysteine and glutathione, an unidentified thiol was observed in the plants exposed to arsenic, which was not found in the control. The concentration of the unidentified thiol showed a very strong and positive correlation with arsenic concentration in the leaflets. The unidentified thiol was low in rachises and undetectable in the roots for As-treated plants. Total and acid-soluble thiols were also measured and the results indicated that arsenic mainly stimulated the synthesis of acid-soluble thiol in Chinese Brake. The investigations of other trace elements (Cd, Cu, Cr, Zn, Pb, Hg, and Se) showed that these elements were not accumulated in Chinese Brake to high levels and the synthesis of the unidentified thiol in the plant was not observed. Our study suggests that the unidentified thiol was induced specifically by arsenic and the distribution patterns of the unidentified thiol and arsenic in the plant were consistent, indicating that the synthesis of this compound was related to As exposure.

  20. Arsenic

    MedlinePlus

    ... and minerals. Arsenic compounds are used to preserve wood, as pesticides, and in some industries. Arsenic can ... Breathing sawdust or burning smoke from arsenic-treated wood Living in an area with high levels of ...

  1. Arsenic

    MedlinePlus

    ... lesions and skin cancer are the most characteristic effects. Drinking-water and food The greatest threat to public health from arsenic originates from contaminated groundwater. Inorganic arsenic ...

  2. RADIOACTIVE ELEMENTS IN THE STANDARD ATOMIC WEIGHTS TABLE

    SciTech Connect

    Holden, N.E.; Holden, N.; Holden,N.E.

    2011-07-27

    In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (or longest-lived) known isotope as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular element has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of 'these constants' for use in various chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was the most stable, i.e., the one with the longest known half-life. In their 1973 Report, the Commission noted that the users of the main Table of Atomic Weights were dissatisfied with the omission of values for some elements in that Table and it was decided to reintroduce the mass number for the radioactive elements into the main Table. In their 1983 Report, the Commission decided that radioactive elements were considered to lack a characteristic terrestrial isotopic composition

  3. Arsenic and other elements in hair, nails, and skin-scales of arsenic victims in West Bengal, India.

    PubMed

    Samanta, Gautam; Sharma, Ramesh; Roychowdhury, Tarit; Chakraborti, Dipankar

    2004-06-29

    For the first time, biological tissues (hair, nails, and skin-scales) of arsenic victims from an arsenic affected area of West Bengal (WB), India were analyzed for trace elements. Analysis was carried out by inductively coupled plasma-mass spectrometry (ICP-MS) for 10 elements (As, Se, Hg, Zn, Pb, Ni, Cd, Mn, Cu, and Fe). A microwave digester was used for digestion of the tissue samples. To validate the method, certified reference materials--human hair (GBW 07601) and bovine muscle (CRM 8414)--were analyzed for all elements. The W test was used to study the normal/log normal distribution for each element in the tissue samples. For hair (n=44) and nails (n=33), all elements show log-normal distribution. For skin-scale samples (n=11), data are not sufficient to provide the information about the trend. Geometric mean, standard error, and range for each element were presented and compared with literature values for other populations. This study reveals the higher levels of toxic elements As, Mn, Pb, and Ni in the tissue samples compared with available values in the literature. The elevated levels of these toxic metals in the tissues may be due to exposure of these elements through drinking water and food. The correlations of Mn and Ni with other essential elements, e.g. Fe, Cu, Zn, suggest that Mn and Ni may substitute for those elements in hair, nails, and skin-scales. However, correlation represents the relation between two elements only and does not take into consideration of the presence of other elements. Principle component analysis was applied to explain the behavior among the elements present in hair and nails. This study reveals that in the arsenic-affected areas of WB, the concentrations of other toxic elements in drinking water and foodstuff should be monitored to evaluate the arsenic poisoning. Copryright 2003 Elsevier B.V.

  4. Arsenic: A Review of the Element's Toxicity, Plant Interactions, and Potential Methods of Remediation.

    PubMed

    Hettick, Bryan E; Cañas-Carrell, Jaclyn E; French, Amanda D; Klein, David M

    2015-08-19

    Arsenic is a naturally occurring element with a long history of toxicity. Sites of contamination are found worldwide as a result of both natural processes and anthropogenic activities. The broad scope of arsenic toxicity to humans and its unique interaction with the environment have led to extensive research into its physicochemical properties and toxic behavior in biological systems. The purpose of this review is to compile the results of recent studies concerning the metalloid and consider the chemical and physical properties of arsenic in the broad context of human toxicity and phytoremediation. Areas of focus include arsenic's mechanisms of human toxicity, interaction with plant systems, potential methods of remediation, and protocols for the determination of metals in experimentation. This assessment of the literature indicates that controlling contamination of water sources and plants through effective remediation and management is essential to successfully addressing the problems of arsenic toxicity and contamination.

  5. Elemental contents in Napoleon's hair cut before and after his death: did Napoleon die of arsenic poisoning?

    PubMed

    Lin, Xilei; Alber, D; Henkelmann, R

    2004-05-01

    Whether or not Napoleon died of arsenic poisoning is an open question on which debate has been active since 1960. This work examined several of his hairs, cut at different times and in different places: two pieces cut the day after his death on the island of St. Helena (1821) and two pieces cut seven years earlier (1814) during his first exile on the island of Elba. INAA results show that all of the samples of Napoleon's hair have an elevated arsenic concentration. These results disfavor the arsenic poisoning theory. Aside from arsenic, 18 other elements are reported, providing additional information for examining the arsenic poisoning theory.

  6. Arsenic

    MedlinePlus

    ... As a preservative in pressure-treated lumber In pesticides As a preservative in animal hides As an ... dust. Arsenic was a common ingredient in many pesticides and herbicides in the past. People who made, ...

  7. Bioleaching of rare earth and radioactive elements from red mud using Penicillium tricolor RM-10.

    PubMed

    Qu, Yang; Lian, Bin

    2013-05-01

    The aim of this work is to investigate biological leaching of rare earth elements (REEs) and radioactive elements from red mud, and to evaluate the radioactivity of the bioleached red mud used for construction materials. A filamentous, acid-producing fungi named RM-10, identified as Penicillium tricolor, is isolated from red mud. In our bioleaching experiments by using RM-10, a total concentration of 2% (w/v) red mud under one-step bioleaching process was generally found to give the maximum leaching ratios of the REEs and radioactive elements. However, the highest extraction yields are achieved under two-step bioleaching process at 10% (w/v) pulp density. At pulp densities of 2% and 5% (w/v), red mud processed under both one- and two-step bioleaching can meet the radioactivity regulations in China.

  8. Vascular Imaging of Solid Tumors in Rats with a Radioactive Arsenic-Labeled Antibody that Binds Exposed Phosphatidylserine

    PubMed Central

    Jennewein, Marc; Lewis, Matthew A.; Zhao, Dawen; Tsyganov, Edward; Slavine, Nikolai; He, Jin; Watkins, Linda; Kodibagkar, Vikram D.; O'Kelly, Sean; Kulkarni, Padmakar; Antich, Peter P.; Hermanne, Alex; Roösch, Frank; Mason, Ralph P.; Thorpe, Philip E.

    2012-01-01

    Purpose We recently reported that anionic phospholipids, principally phosphatidylserine, become exposed on the external surface of vascular endothelial cells in tumors, probably in response to oxidative stresses present in the tumor microenvironment. In the present study, we tested the hypothesis that a chimeric monoclonal antibody that binds phosphatidylserine could be labeled with radioactive arsenic isotopes and used for molecular imaging of solid tumors in rats. Experimental Design Bavituximab was labeled with 74As (β+,T1/2 17.8 days) or 77As (β−,T1/2 1.6 days) using a novel procedure. The radionuclides of arsenic were selected because their long half-lives are consistent with the long biological half lives of antibodies in vivo and because their chemistry permits stable attachment to antibodies. The radiolabeled antibodies were tested for the ability to image subcutaneous Dunning prostate R3227-AT1 tumors in rats. Results Clear images of the tumors were obtained using planar γ-scintigraphy and positron emission tomography. Biodistribution studies confirmed the specific localization of bavituximab to the tumors. The tumor-to-liver ratio 72 h after injection was 22 for bavituximab compared with 1.5 for an isotype-matched control chimeric antibody of irrelevant specificity. Immunohistochemical studies showed that the bavituximab was labeling the tumor vascular endothelium. Conclusions These results show that radioarsenic-labeled bavituximab has potential as a new tool for imaging the vasculature of solid tumors. PMID:18316558

  9. Distribution and variation of arsenic in Wisconsin surface soils, with data on other trace elements

    USGS Publications Warehouse

    Stensvold, Krista A.

    2012-01-01

    Soils with sandy glacial outwash as a parent material have a lower median arsenic concentration (1.0 mg/kg) than soils forming in other parent materials (1.5 to 3.0 mg/kg). Soil texture and drainage category also influence median arsenic concentration. Finer grained soils have a higher observed range of concentrations. For loamy and loess-dominated soil groups, drainage category influences the median arsenic concentration and observed range of values, but a consistent relationship within the data is not apparent. Statistical analysis of the 16 other elements are presented in this report, but the relationships of concentrations to soil properties or geographic areas were not examined.

  10. The problem of burying radioactive wastes containing transplutonium elements (TPE)

    SciTech Connect

    Bryzgalova, R.V.; Krivokhatskii, A.S.; Rogozin, Y.M.; Sinitsyna, G.S.

    1986-09-01

    This paper discusses the problem of burying radioactive wastes containing TPE. The most acceptable and developed method at present is that of disposal into continental, deep-lying, geological formatins. Based on an analysis of estimates of the thermal conditions on burying highly active wastes, including TPE concentrates, data on the filtration and sorption characteristics of rocks, estimates of the diffusion of radionuclide species capable of migrating, and taking into account the retention powers of rocks it is concluded that it is possible to bury such wastes in weakly permeable geological formations possessing shielding characteristics which ensure reliability and safety in burial.

  11. Effect of Arsenic on Growth, Arsenic Uptake, Distribution of Nutrient Elements and Thiols in Seedlings of Wrightia arborea (Dennst.) Mabb.

    PubMed

    Kumar, Dharmendra; Singh, Vijay Pratap; Tripathi, Durgesh Kumar; Prasad, Sheo Mohan; Chauhan, Devendra Kumar

    2015-01-01

    Hydroponic experiments were conducted to investigate the effect of arsenic on seedlings of Wrightia arborea and Holoptelea integrifolia. Results revealed that W. arborea could tolerate much higher arsenic concentration than H. integrifolia. Therefore, further investigations were focused on W. arborea using higher arsenic concentrations (0.2-2.0 mM). Seedlings of W. arborea accumulated about 312-2147 and 1048-5688 mg/kg dry weight of arsenic in shoots and roots, respectively, following treatments with 0.2-1.5 mM of arsenic without exhibiting arsenic toxicity signs. However, arsenic at 2.0 mM caused decline in growth. Macronutrients content such as Ca, S (except at 2.0 mM), and K (only in root) increased while Mg, P, and K (shoot) decreased by arsenic treatments. However, the content of micronutrients was enhanced under arsenic treatments. Non-protein thiols (NP-SH) showed positive correlations with arsenic doses up to 0.2-1.5 mM but at 2.0 mM there was a decline in NP-SH thus suggesting important role of NP-SH in imparting arsenic tolerance. This study demonstrated that W. arborea that could tolerate arsenic concentrations up to 0.2-1.5 mM may be useful in arsenic phytoremediation programs.

  12. Separation and recovery of radioactive and non-radioactive toxic trace elements from aqueous industrial effluents.

    PubMed

    Iyer, R H

    2003-09-01

    An update is presented on liquid membrane-based processes as viable and relevant alternatives to conventional approaches such as precipitation, solvent extraction, ion exchange processes and electrochemical techniques for the removal and recovery of some toxic and/or valuable trace metal ions including some actinides and fission products e.g. U, Am, Y etc and As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Zn etc from radioactive as well as non-radioactive aqueous waste solutions respectively. In particular, results of experiments aimed at developing supported liquid membrane(SLM)-based process using commercially available porous membranes and indigenously prepared track--etch membranes (TEMs) have been critically examined in laboratory studies to generate basic data needed to evaluate their utility for continuous operation without regeneration. These include effect of pore size, porosity, optimum pore size and their reusability. It is clearly demonstrated that indigenously prepared 10 microm thick TEMs with a porosity in the range of 2-5% give comparable transport rates for metal ions-matching with that of commercial membranes of much higher thickness (160 microm) and higher porosity of 60-85%. The smaller thickness of TEMs more than compensates for their lower porosity. It is shown that because of their well defined pore characteristics TEMs could serve as model supports in SLM studies. By comparing the values of permeability coefficient (P) for TEM and polytetraflouroethylene (PTFE) supports for the transport of Pb2+ chosen as a typical divalent metal ion, and using di-2 ethyl hexyl phosphoric acid (D2EHPA) as the carrier, it is unambiguously proved that diffusion of the metal complex across the membrane is the rate controlling step in metal ion transport in SLM-based processes. An overview of the experimental findings along with future outlook and suggestions for further work are presented in this paper.

  13. [Impact of Radioactive Elements on Microbial Complexes in Cryogenic Soils of Yakutia].

    PubMed

    Ivanova, T I; Kuz'mina, N P; Sobakin, P I

    2016-01-01

    It has been found that microorganisms in cryogenic soils of Yakutia are resistant to the long-term impact of cesium and thorium. The number of microorganisms in the studied ecological-trophic groups does not depend on the concentrations of radioactive elements. Differences in the number of microorganisms are determined by the physicochemical conditions that are created in different horizons of the soils studied. The long-term impact of radiation (for 36 and 66 years) on microorganisms inhabiting the permafrost soils of Yakutia has developed their adaptive capacity to high concentrations of these radioactive elements.

  14. Arsenic in Bangladeshi soils related to physiographic region, paddy management, and mirco- and macro-elemental status.

    PubMed

    Chowdhury, M Tanvir A; Deacon, Claire M; Jones, Gerrad D; Imamul Huq, S M; Williams, Paul N; Manzurul Hoque, A F M; Winkel, Lenny H E; Price, Adam H; Norton, Gareth J; Meharg, Andrew A

    2017-07-15

    While the impact of arsenic in irrigated agriculture has become a major environmental concern in Bangladesh, to date there is still a limited understanding of arsenic in Bangladeshi paddy soils at a landscape level. A soil survey was conducted across ten different physiographic regions of Bangladesh, which encompassed six types of geomorphology (Bil, Brahmaputra floodplain, Ganges floodplain, Meghna floodplain, Karatoya-Bangali floodplain and Pleistocene terrace). A total of 1209 paddy soils and 235 matched non-paddy soils were collected. The source of irrigation water (groundwater and surface water) was also recorded. The concentrations of arsenic and sixteen other elements were determined in the soil samples. The concentration of arsenic was higher in paddy soils compared to non-paddy soils, with soils irrigated with groundwater being higher in arsenic than those irrigated with surface water. There was a clear difference between the Holocene floodplains and the Pleistocene terraces, with Holocene floodplain soils being higher in arsenic and other elements. The results suggest that arsenic is most likely associated with less well weathered/leached soils, suggesting it is either due to the geological newness of Holocene sediments or differences between the sources of sediments, which gives rise to the arsenic problems in Bangladeshi soils.

  15. Distribution of a suite of elements including arsenic and mercury in Alabama coal

    USGS Publications Warehouse

    Goldhaber, Martin B.; Bigelow, R.C.; Hatch, J.R.; Pashin, J.C.

    2000-01-01

    Arsenic and other elements are unusually abundant in Alabama coal. This conclusion is based on chemical analyses of coal in the U.S. Geological Survey's National Coal Resources Data System (NCRDS; Bragg and others, 1994). According to NCRDS data, the average concentration of arsenic in Alabama coal (72 ppm) is three times higher than is the average for all U.S. coal (24 ppm). Of the U.S. coal analyses for arsenic that are at least 3 standard deviations above the mean, approximately 90% are from the coal fields of Alabama. Figure 1 contrasts the abundance of arsenic in coal of the Warrior field of Alabama (histogram C) with that of coal of the Powder River Basin, Wyoming (histogram A), and the Eastern Interior Province including the Illinois Basin and nearby areas (histogram B). The Warrior field is by far the largest in Alabama. On the histogram, the large 'tail' of very high values (> 200 ppm) in the Warrior coal contrasts with the other two regions that have very few analyses greater than 200 ppm.

  16. State-of-the-art coordination chemistry of radioactive elements

    NASA Astrophysics Data System (ADS)

    Kharisov, B. I.; Mendez-Rojas, Miguel A.

    2001-10-01

    Modern procedures for the synthesis of coordination and organometallic compounds of actinides and technetium and the properties of these compounds are surveyed. Experimental techniques, including methods for the synthesis of actinide and technetium complexes from elemental metals (oxidative dissolution and direct electrosynthesis), salts and halide, carbonyl and other complexes are generalised. The bibliography includes 283 references.

  17. Strategies for the engineered phytoremediation of toxic element pollution: mercury and arsenic.

    PubMed

    Meagher, Richard B; Heaton, Andrew C P

    2005-12-01

    Plants have many natural properties that make them ideally suited to clean up polluted soil, water, and air, in a process called phytoremediation. We are in the early stages of testing genetic engineering-based phytoremediation strategies for elemental pollutants like mercury and arsenic using the model plant Arabidopsis. The long-term goal is to develop and test vigorous, field-adapted plant species that can prevent elemental pollutants from entering the food-chain by extracting them to aboveground tissues, where they can be managed. To achieve this goal for arsenic and mercury, and pave the way for the remediation of other challenging elemental pollutants like lead or radionucleides, research and development on native hyperaccumulators and engineered model plants needs to proceed in at least eight focus areas: (1) Plant tolerance to toxic elementals is essential if plant roots are to penetrate and extract pollutants efficiently from heterogeneous contaminated soils. Only the roots of mercury- and arsenic-tolerant plants efficiently contact substrates heavily contaminated with these elements. (2) Plants alter their rhizosphere by secreting various enzymes and small molecules, and by adjusting pH in order to enhance extraction of both essential nutrients and toxic elements. Acidification favors greater mobility and uptake of mercury and arsenic. (3) Short distance transport systems for nutrients in roots and root hairs requires numerous endogenous transporters. It is likely that root plasma membrane transporters for iron, copper, zinc, and phosphate take up ionic mercuric ions and arsenate. (4) The electrochemical state and chemical speciation of elemental pollutants can enhance their mobility from roots up to shoots. Initial data suggest that elemental and ionic mercury and the oxyanion arsenate will be the most mobile species of these two toxic elements. (5) The long-distance transport of nutrients requires efficient xylem loading in roots, movement through the

  18. Radioactivity and elemental analysis in the Ruseifa municipal landfill, Jordan.

    PubMed

    Al-Jundi, J; Al-Tarazi, E

    2008-01-01

    In this study, a low background gamma-ray spectrometer based on a Hyper Pure Germanium detector was used to determine the activity concentrations of natural radionuclides in soil samples from various locations within the Ruseifa municipal landfill in Jordan. The chemical composition of the samples was also determined using a Wavelength Dispersive X-Ray Fluorescence Spectrometer. The maximum and minimum annual outdoor effective doses were found to be 103 and 36microSva(-1) in the old landfill and Abu-Sayaah village, respectively. The annual outdoor effective dose at the recent landfill site was found to be 91microSva(-1). The annual effective dose equivalents from outdoor terrestrial gamma radiation at the old landfill and the recent landfill were higher than the typical worldwide value of 70microSva(-1). Thus, some remediation of the soils on both old and recent landfills should be considered before any development for public activities. This could be achieved by mixing with clean soil from areas which are known to have lower radiation background. The concentration of heavy metals Zn, Cr, and Ba in the three sites included in this study were found to be higher than the background levels in the soil samples of the control area (Abu-Sayaah village). The enrichment factors for the above three elements were calculated and found to be: complex building site: Zn=2.52 and Ba=1.33; old landfill site: Cr=1.88, Zn=3.64, and Ba=1.26; and recent landfill site: Cr=1.57, Zn=2.19, and Ba=1.28. There was a strong negative correlation between the concentrations of the metallic elements (Mg, Al, Mn, Fe and Rb) and the concentrations of Zn, Ba, and Cr. Moreover, a strong positive correlation was found between Zn, Ba, and Cr. Thus these elements were enriched in the solid waste.

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

    PubMed

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

    2013-03-01

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

  20. Compositional modification of Se-Ge-Sb chalcogenide glasses by addition of arsenic element

    NASA Astrophysics Data System (ADS)

    Ghayebloo, M.; Tavoosi, M.; Rezvani, M.

    2017-06-01

    The modification of structural, thermal and optical properties of Se-Ge-Sb glasses by addition of arsenic element was the goal of this study. In this regards, six different glasses of Se60Ge40-xSb5Asx (0 ≤ x ≤ 15) were prepared by conventional melt quenching technique in quartz ampoule. The produced samples were characterized using X-ray diffraction (XRD), differential scanning calorimetry (DSC), UV-Vis-NIR spectrophotometer, Fourier transform infrared (FTIR) and Raman spectroscopy. The fundamental absorption edge for of the glasses was analyzed in terms of the theory proposed by Davis and Mott. Based on the obtained results, the glass transition temperature, optical energy gap and Urbach energy of prepared glasses in this alloying system were in the range of 325-380 °C, 1.43-1.64 eV and 0.03-0.3547 eV, respectively. The as prepared glasses show anomalous behavior at 5-7.5 mole% of arsenic for the glass transition temperature, transmittance, absorption edge, optical energy gap and Urbach energy. Based on the Raman spectra, the structural analysis indicates that, increasing the network connectivity upon increasing the arsenic content up to 7.5 mole% is the main reason of anomalous behavior in Se60Ge40-xSb5Asx (0 ≤ x ≤ 15) system.

  1. Method for disposing of radioactive graphite and silicon carbide in graphite fuel elements

    SciTech Connect

    Gay, R.L.

    1995-09-12

    Method is described for destroying radioactive graphite and silicon carbide in fuel elements containing small spheres of uranium oxide coated with silicon carbide in a graphite matrix, by treating the graphite fuel elements in a molten salt bath in the presence of air, the salt bath comprising molten sodium-based salts such as sodium carbonate and a small amount of sodium sulfate as catalyst, or calcium-based salts such as calcium chloride and a small amount of calcium sulfate as catalyst, while maintaining the salt bath in a temperature range of about 950 to about 1,100 C. As a further feature of the invention, large radioactive graphite fuel elements, e.g. of the above composition, can be processed to oxidize the graphite and silicon carbide, by introducing the fuel element into a reaction vessel having downwardly and inwardly sloping sides, the fuel element being of a size such that it is supported in the vessel at a point above the molten salt bath therein. Air is bubbled through the bath, causing it to expand and wash the bottom of the fuel element to cause reaction and destruction of the fuel element as it gradually disintegrates and falls into the molten bath. 4 figs.

  2. Consumption of arsenic and other elements from vegetables and drinking water from an arsenic-contaminated area of Bangladesh.

    PubMed

    Rahman, Mohammad Mahmudur; Asaduzzaman, Md; Naidu, Ravi

    2013-11-15

    The study assesses the daily consumption by adults of arsenic (As) and other elements in drinking water and home-grown vegetables in a severely As-contaminated area of Bangladesh. Most of the examined elements in drinking water were below the World Health Organization (WHO) guideline values except As. The median concentrations of As, cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), lead (Pb), Mn, nickel (Ni), and zinc (Zn) in vegetables were 90 μg kg(-1), 111 μg kg(-1), 0.80 mg kg(-1), 168 μg kg(-1), 13 mg kg(-1), 2.1 mg kg(-1), 65 mg kg(-1), 1.7 mg kg(-1), and 50 mg kg(-1), respectively. Daily intakes of As, Cd, Cr, Co, Cu, Pb, manganese (Mn), Ni, and Zn from vegetables and drinking water for adults were 839 μg, 2.9 μg, 20.8 μg, 5.5 μg, 0.35 mg, 56.4 μg, 2.0mg, 49.1 μg, and 1.3mg, respectively. The health risks from consuming vegetables were estimated by comparing these figures with the WHO/FAO provisional tolerable weekly or daily intake (PTWI or PTDI). Vegetables alone contribute 0.05 μg of As and 0.008 mg of Cu per kg of body weight (bw) daily; 0.42 μg of Cd, 8.77 mg of Pb, and 0.03 mg of Zn per kg bw weekly. Other food sources and particularly dietary staple rice need to be evaluated to determine the exact health risks from such foods. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Tabulation of thermodynamic data for chemical reactions involving 58 elements common to radioactive waste package systems

    SciTech Connect

    Benson, L.V.; Teague, L.S.

    1980-08-01

    The rate of release and migration of radionuclides from a nuclear waste repository to the biosphere is dependent on chemical interactions between groundwater, the geologic host rock, and the radioactive waste package. For the purpose of this report, the waste package includes the wasteform, canister, overpack, and repository backfill. Chemical processes of interest include sorption (ion exchange), dissolution, complexation, and precipitation. Thermochemical data for complexation and precipitation calculations for 58 elements common to the radioactive waste package are presented. Standard free energies of formation of free ions, complexes, and solids are listed. Common logarithms of equilibrium constants (log K's) for speciation and precipitation reactions are listed. Unless noted otherwise, all data are for 298.15/sup 0/K and one atmosphere.

  4. An experimental method for quantitatively evaluating the elemental processes of indoor radioactive aerosol behavior.

    PubMed

    Yamazawa, H; Yamada, S; Xu, Y; Hirao, S; Moriizumi, J

    2015-11-01

    An experimental method for quantitatively evaluating the elemental processes governing the indoor behaviour of naturally occurring radioactive aerosols was proposed. This method utilises transient response of aerosol concentrations to an artificial change in aerosol removal rate by turning on and off an air purifier. It was shown that the indoor-outdoor exchange rate and the indoor deposition rate could be estimated by a continuous measurement of outdoor and indoor aerosol number concentration measurements and by the method proposed in this study. Although the scatter of the estimated parameters is relatively large, both the methods gave consistent results. It was also found that the size distribution of radioactive aerosol particles and hence activity median aerodynamic diameter remained not largely affected by the operation of the air purifier, implying the predominance of the exchange and deposition processes over other processes causing change in the size distribution such as the size growth by coagulation and the size dependence of deposition.

  5. Radioactive Fission Product Release from Defective Light Water Reactor Fuel Elements

    SciTech Connect

    Konyashov, Vadim V.; Krasnov, Alexander M.

    2002-04-15

    Results are provided of the experimental investigation of radioactive fission product (RFP) release, i.e., krypton, xenon, and iodine radionuclides from fuel elements with initial defects during long-term (3 to 5 yr) irradiation under low linear power (5 to 12 kW/m) and during special experiments in the VK-50 vessel-type boiling water reactor.The calculation model for the RFP release from the fuel-to-cladding gap of the defective fuel element into coolant was developed. It takes into account the convective transport in the fuel-to-cladding gap and RFP sorption on the internal cladding surface and is in good agreement with the available experimental data. An approximate analytical solution of the transport equation is given. The calculation dependencies of the RFP release coefficients on the main parameters such as defect size, fuel-to-cladding gap, temperature of the internal cladding surface, and radioactive decay constant were analyzed.It is shown that the change of the RFP release from the fuel elements with the initial defects during long-term irradiation is, mainly, caused by fuel swelling followed by reduction of the fuel-to-cladding gap and the fuel temperature. The calculation model for the RFP release from defective fuel elements applicable to light water reactors (LWRs) was developed. It takes into account the change of the defective fuel element parameters during long-term irradiation. The calculation error according to the program does not exceed 30% over all the linear power change range of the LWR fuel elements (from 5 to 26 kW/m)

  6. Trace elements as paradigms of developmental neurotoxicants: lead, methylmercury and arsenic

    PubMed Central

    Grandjean, Philippe; Herz, Katherine T.

    2014-01-01

    Trace elements have contributed unique insights into developmental neurotoxicity and serve as paradigms for such adverse effects. Many trace elements are retained in the body for long periods and can be easily measured to assess exposure by inexpensive analytical methods that became available several decades ago so that past and cumulated exposures could be easily characterized through analysis of biological samples, e.g. blood and urine. The first compelling evidence resulted from unfortunate poisoning events that allowed scrutiny of long-term outcomes of acute exposures that occurred during early development. Pursuant to this documentation, prospective studies of children's cohorts that applied sensitive neurobehavioral methods supported the notion that the brain is uniquely vulnerable to toxic damage during early development. Lead, methylmercury, and arsenic thereby serve as paradigm neurotoxicants that provide a reference for other substances that may have similar adverse effects. Less evidence is available on manganese, fluoride, and cadmium, but experience from the former trace elements suggest that, with time, adverse effects are likely to be documented at exposures previously thought to be low and safe. PMID:25175507

  7. Trace elements as paradigms of developmental neurotoxicants: Lead, methylmercury and arsenic.

    PubMed

    Grandjean, Philippe; Herz, Katherine T

    2015-01-01

    Trace elements have contributed unique insights into developmental neurotoxicity and serve as paradigms for such adverse effects. Many trace elements are retained in the body for long periods and can be easily measured to assess exposure by inexpensive analytical methods that became available several decades ago so that past and cumulated exposures could be easily characterized through analysis of biological samples, e.g. blood and urine. The first compelling evidence resulted from unfortunate poisoning events that allowed scrutiny of long-term outcomes of acute exposures that occurred during early development. Pursuant to this documentation, prospective studies of children's cohorts that applied sensitive neurobehavioral methods supported the notion that the brain is uniquely vulnerable to toxic damage during early development. Lead, methylmercury, and arsenic thereby serve as paradigm neurotoxicants that provide a reference for other substances that may have similar adverse effects. Less evidence is available on manganese, fluoride, and cadmium, but experience from the former trace elements suggest that, with time, adverse effects are likely to be documented at exposures previously thought to be low and safe. Copyright © 2014 Elsevier GmbH. All rights reserved.

  8. Radioactive elements on Mercury's surface from MESSENGER: implications for the planet's formation and evolution.

    PubMed

    Peplowski, Patrick N; Evans, Larry G; Hauck, Steven A; McCoy, Timothy J; Boynton, William V; Gillis-Davis, Jeffery J; Ebel, Denton S; Goldsten, John O; Hamara, David K; Lawrence, David J; McNutt, Ralph L; Nittler, Larry R; Solomon, Sean C; Rhodes, Edgar A; Sprague, Ann L; Starr, Richard D; Stockstill-Cahill, Karen R

    2011-09-30

    The MESSENGER Gamma-Ray Spectrometer measured the average surface abundances of the radioactive elements potassium (K, 1150 ± 220 parts per million), thorium (Th, 220 ± 60 parts per billion), and uranium (U, 90 ± 20 parts per billion) in Mercury's northern hemisphere. The abundance of the moderately volatile element K, relative to Th and U, is inconsistent with physical models for the formation of Mercury requiring extreme heating of the planet or its precursor materials, and supports formation from volatile-containing material comparable to chondritic meteorites. Abundances of K, Th, and U indicate that internal heat production has declined substantially since Mercury's formation, consistent with widespread volcanism shortly after the end of late heavy bombardment 3.8 billion years ago and limited, isolated volcanic activity since.

  9. Analytical microscopy and environment. Current developments using bioindicators of pollution by stable and radioactive elements.

    PubMed

    Chassard-Bouchaud, C

    1996-05-01

    Ecotoxicological investigations were performed on three sets of bioindicators. The first one concerns marine pollution of invertebrates (molluscs: the mussel Mytilus edulis and related species, crustaceans: the crab Liocarcinus puber and related species), contaminated by stable or radioactive elements originating from wastes discharged into sea water. The second one concerns freshwater pollution of vertebrates (fish: the brown trout Salmo trutta fario), contaminated by aluminium dissolved in rivers, as a consequence of an atmospheric pollution by acid rain. The third one concerns the atmospheric pollution of trees by plutonium (Casuarina equisetifolia). Mechanisms involved in the uptake, storage and elimination processes of these toxicants were studied, with a special emphasis on cellular and subcellular aspects of concentration sites. Two microanalytical methods were employed: Secondary Ion Mass Spectrometry (SIMS), using the ion microscope and the ion microprobe, and X-ray spectrometry using the electron microprobe (EMP). In marine organisms, the target organs and tissues of bioaccumulation of stable and radioactive elements (238U, 239Pu and 241Am), were shown to be mainly digestive gland, gill and exoskeleton. The target organelles were shown to be spherocrystals and lysosomes. Amoebocytes, enzymatically equipped with lysosomal phosphatase, were involved in the phagocytic clearance of metal pollutants. In trout, insolubilisation of Al phosphate within lysosomes and a high metal concentration within bones were observed. The tree Casuarina equisetifolia exhibits a particular ability to concentrate atmospheric plutonium within its leaves.

  10. Prolong Restoration of the Water Quality of River Ganga Effect of Heavy Metals and Radioactive Elements.

    PubMed

    Tare, Vinod; Basu, Subhankar

    2014-04-01

    The genesis of the present research was the belief since ages and the observations made through some studies that the water of river Ganga has unique characteristics, which allows storage of water quality even on prolong storage. Very few systematic studies have been conducted to support the contention that the Ganga water indeed has some special composition that could be attributed to its unique storage capacity. It was postulated that prolong restoration of water quality depends on the ability to arrest microbial activity that is generally responsible for deterioration in water quality on prolong storage. Hence, attempt has been made to identify the parameters that are likely to influence the prolong storage of river water. Along with Ganga river water, other three major rivers, viz. Yamuna, Godavari and Narmada, were selected for comparison. Emphasis was made on estimation of heavy metals, radioactive elements, dissolved carbon and other physicochemical parameters such as temperature, pH, alkalinity, hardness and dissolved organic carbon. Based on the available information regarding the impact of heavy metals, radioactive elements vis-à-vis the chemical composition of water on microorganisms in the aquatic environment, an overall impact score for the waters of the four Indian rivers selected in the study has been assigned.

  11. MESSENGER Measurements of Radioactive Elements on Mercury: Implications for the Planet's Formation and Evolution

    NASA Astrophysics Data System (ADS)

    Evans, L. G.; Peplowski, P. N.; Hauck, S. A.; McCoy, T. J.; Boynton, W. V.; Ebel, D. S.; Goldsten, J. O.; Hamara, D. K.; Lawrence, D. J.; McNutt, R. L.; Rhodes, E. A.; Nittler, L. R.; Sprague, A. L.; Solomon, S. C.; Starr, R. D.

    2011-12-01

    Measurements of the surface composition of Mercury offers a window into the epoch of planet formation in the inner solar system. Mercury likely preserves a more complete record of early crustal formation than do Venus, Earth, or Mars, each of which experienced extensive and prolonged resurfacing and near-surface alteration since earliest crustal formation. The MErcury Surface, Space ENvironment, GEochemisty, and Ranging (MESSENGER) spacecraft was inserted into Mercury orbit on 18 March 2011 and carries a suite of instruments designed for remote sensing of elemental and mineralogical composition including a Gamma-Ray Spectrometer (GRS). We report measured surface abundances of radioactive elements on Mercury and their implications for hypotheses regarding the planet's formation and thermal evolution. The average surface abundances of radioactive elements over the region of Mercury measured by the GRS are 1150 ± 220 ppm K, 220 ± 60 ppb Th, and 90 ± 20 ppb U. Ratios of the moderately volatile incompatible element K to the refractory incompatible elements Th and U provide insights into the volatile inventory of planetary bodies. The measured K/Th ratio for Mercury (5200 ± 1800) is comparable to values for the other terrestrial planets. By contrast, the lunar K/Th value (360) is an order of magnitude lower, indicative of the depletion of lunar volatiles relative to Earth. Mercury's K/Th ratio, combined with the high abundance of the volatile element sulfur measured by the MESSENGER X-Ray Spectrometer, indicates that the planet has a volatile inventory similar to those of the other terrestrial planets. Hypotheses proposed to explain the unusually high ratio of metal to silicate on Mercury also carry predictions for the ratios of volatile to refractory elements that can be tested against the K, Th, and U abundances measured by MESSENGER. The abundance of K, relative to Th and U, is inconsistent with physical models for the formation of Mercury requiring extreme

  12. Groundwater contamination with arsenic, Selenium and other trace elements in Quetta Valley, Pakistan

    NASA Astrophysics Data System (ADS)

    Khan, S. D.; Xiong, Y.; Mahmood, K.; Khan, A. S.; Sultan, M.

    2009-12-01

    This work presents major, minor and trace elements data for groundwater samples collected from wells, tube wells, springs and karezes from Quetta Valley. Collected samples were quantitatively analyzed using ICP (AES) and ICP (MS) for the determination of major (Ca, K, Mg, Na, Si, Cl- and SO4), minor and trace elements (Fe, Mn, B, Ba, Li, Sr, Li, Be, B, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Y, Ag, Cd, Cs, Ba, La, Ce, Pr, Nd145, Nd146, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, Tl, Pb, Th, U). Quetta Valley in Pakistan has frequently experienced shortage of groundwater. In recent years, the water quality has had a sharp decline at many locations. The study of groundwater resources in this valley is an attempt to understand the causes of and sources of contamination. At several locations, nitrate, sulfate, arsenic, selenium, chromium and nickel contamination has been determined. The preliminary results indicate that these contaminations apparently result from a combination of rock alteration and mining activity in the area. Different water sources could have also contributed to the deterioration of the water quality of Quetta Valley. This research provides the basis for future work, which will involve detailed hydrological modeling and water quality studies.

  13. Influence of waterborne arsenic on nutritive and potentially harmful elements in gilthead seabream (Sparus aurata).

    PubMed

    Pérez-Sirvent, Carmen; Martínez-Sánchez, Maria José; López, Salvadora Martínez; Del Carmen Gómez Martínez, Maria; Guardiola, Francisco A; Esteban, María Ángeles

    2016-11-01

    Fish are an important source of nutrients in human nutrition. Although arsenic (As) is considered potentially carcinogenic for human being, very little is known about its toxicity in fish biology. To increase our knowledge of the effect of exposure to waterborne As on fish, gilthead seabream (Sparus aurata) were exposed to 5 μM As2O3 and the bioaccumulation of macronutrients (Ca, K, Mg, Na, P), micronutrients (Fe, Mn, Zn) and Potentially Harmful Elements (As, Cd) was determined using spectrometric techniques. All elements were determined in the muscle and liver of non-exposed fish and those exposed to As for 2, 10 or 30 days. The concentrations of K, Na, Mg, Mn and Zn (in muscle) and Fe and Mn (in liver) of control (non-exposed) fish were higher than those determined in exposed fish. Furthermore, neither As nor Cd accumulated in the edible part (muscle) of seabream and were only evident in liver after 30 days of continuous exposure to As, but both concentrations remained below legally established limits.

  14. Naturally occurring heavy radioactive elements in the geothermal microcosm of the Los Azufres (Mexico) volcanic complex.

    PubMed

    Abuhani, W A; Dasgupta-Schubert, N; Villaseñor, L M; García Avila, D; Suárez, L; Johnston, C; Borjas, S E; Alexander, S A; Landsberger, S; Suárez, M C

    2015-01-01

    The Los Azufres geothermal complex of central Mexico is characterized by fumaroles and boiling hot-springs. The fumaroles form habitats for extremophilic mosses and ferns. Physico-chemical measurements of two relatively pristine fumarolic microcosms point to their resemblance with the paleo-environment of earth during the Ordovician and Devonian periods. These geothermal habitats were analysed for the distribution of elemental mass fractions in the rhizospheric soil (RS), the native volcanic substrate (VS) and the sediments (S), using the new high-sensitivity technique of polarized x-ray energy dispersive fluorescence spectrometry (PEDXRF) as well as instrumental neutron activation analysis (INAA) for selected elements. This work presents the results for the naturally occurring heavy radioactive elements (NOHRE) Bi, Th and U but principally the latter two. For the RS, the density was found to be the least and the total organic matter content the most. Bi was found to be negligibly present in all substrate types. The average Th and U mass fractions in the RS were higher than in the VS and about equal to their average mass fractions in the S. The VS mass fraction of Th was higher, and of U lower, than the mass fractions in the earth's crust. In fact for the fumaroles of one site, the average RS mass fractions of these elements were higher than the averaged values for S (without considering the statistical dispersion). The immobilization of the NOHRE in the RS is brought about by the bio-geochemical processes specific to these extremophiles. Its effectiveness is such that despite the small masses of these plants, it compares with, or may sometimes exceed, the immobilization of the NOHRE in the S by the abiotic and aggressive chemical action of the hot-springs. These results indicate that the fumarolic plants are able to transform the volcanic substrate to soil and to affect the NOHRE mass fractions even though these elements are not plant nutrients. Mirrored back to

  15. Metal complexes containing natural and and artificial radioactive elements and their applications.

    PubMed

    Kharissova, Oxana V; Méndez-Rojas, Miguel A; Kharisov, Boris I; Méndez, Ubaldo Ortiz; Martínez, Perla Elizondo

    2014-07-24

    Recent advances (during the 2007-2014 period) in the coordination and organometallic chemistry of compounds containing natural and artificially prepared radionuclides (actinides and technetium), are reviewed. Radioactive isotopes of naturally stable elements are not included for discussion in this work. Actinide and technetium complexes with O-, N-, N,O, N,S-, P-containing ligands, as well π-organometallics are discussed from the view point of their synthesis, properties, and main applications. On the basis of their properties, several mono-, bi-, tri-, tetra- or polydentate ligands have been designed for specific recognition of some particular radionuclides, and can be used in the processes of nuclear waste remediation, i.e., recycling of nuclear fuel and the separation of actinides and fission products from waste solutions or for analytical determination of actinides in solutions; actinide metal complexes are also usefulas catalysts forcoupling gaseous carbon monoxide,as well as antimicrobial and anti-fungi agents due to their biological activity. Radioactive labeling based on the short-lived metastable nuclide technetium-99m ((99m)Tc) for biomedical use as heart, lung, kidney, bone, brain, liver or cancer imaging agents is also discussed. Finally, the promising applications of technetium labeling of nanomaterials, with potential applications as drug transport and delivery vehicles, radiotherapeutic agents or radiotracers for monitoring metabolic pathways, are also described.

  16. Remote detection of toxic and radioactive elements in sea water and ice

    NASA Astrophysics Data System (ADS)

    Chistyakova, Liliya K.; Kopytin, Yurii D.; Penin, Sergei T.; Chikurov, Vladimir A.

    1997-12-01

    The paper describes the results of experimental investigations and instrumental realization of remote method of laser induced breakdown spectroscopy (LIBS) for express diagnostics of highly toxic and radioactive elements in the water. As an example the samples of oxides of non-ferrous metals and uranium are used. The emission spectrum of materials is excited in non-equilibrium plasma of a laser spark. A laser source provides in the radiation focusing range at a wavelength of 10.6 mm the peak radiation density 108 - 5 X 107 W/cm2, the pulse duration at half-altitude is 0.3 ms. On the atmospheric experiments the radiation focusing is performed using the Cassegrainian telescope with a large mirror 0.45 m diameter. Statistical data on laser spark initiation have been obtained at distances up to 250 m - - on the solid and liquid targets.

  17. Natural radioactivity and rare earth elements in feldspar samples, Central Eastern desert, Egypt.

    PubMed

    Walley El-Dine, Nadia; El-Shershaby, Amal; Afifi, Sofia; Sroor, Amany; Samir, Eman

    2011-05-01

    The pegmatite bodies of the Eastern Desert of Egypt are widely distributed especially along the Marsa-Alam-Idfu road. The Abu Dob area covers about 150km(2) of the Arabian Nubian shield at the central part of the Eastern Desert of Egypt. Most of the pegmatite is zoned; the zonation starts with milky quartz at the core followed by alkali feldspar at the margins. The feldspars vary in color from rose to milky and in composition from K-feldspar to Na-feldspar, sometimes interactions of both types are encountered. Thirteen feldspar samples were collected from different locations in the Abu Dob area for measuring the natural radioactivity of (238)U, (232)Th and (40)K using an HPGe detector. The variation in concentration of radionuclides for the area under investigation can be classified into regions of high, medium and low natural radioactivity. The average concentration in BqKg(-1) has been observed to be from 9.5 to 183675.7BqKg(-1) for (238)U, between 6.1 and 94,314.2BqKg(-1) for (232)Th and from 0 to 7894.6BqKg(-1) for (40)K. Radium equivalent activities (Ra(eq)), dose rate (D(R)) and external hazard (H(ex)) have also been determined. In the present work, the concentration of rare earth elements are measured for two feldspar samples using two techniques, Environmental Scanning Electron microscope XIL 30 ESEM, Philips, and Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The existence of rare earth elements in this area are very high and can be used in different important industries. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Finite element modelling of an evacuated canister for removal of molten radioactive glass

    SciTech Connect

    Hatchell, B.K.; Deibler, J.E.; Ketner, G.L.

    1994-05-01

    Pacific Northwest Laboratory (PNL) has prepared a preliminary design for the West Valley Demonstration Project evacuated canister system. The function of the evacuated canister is to remove radioactive molten glass from a hot cell melter cavity during a planned melter shutdown. The proposed evacuated canister system consists of an L-shaped 4-inch 304L stainless steel (SS) schedule 40 pipe, sealed at one end with an aluminum plug and attached at the other end to a canister. While the canister is being filled, it is positioned and held above the melter at approximately 15{degree} from horizontal by two turntable-mounted cranes. ANSYS finite element analyses were conducted to evaluate the heat transfer from the glass to the canister and establish a maximum canister temperature for material strength evaluation. Finite element structural analyses were conducted to identify areas that required reinforcement for high temperature use. Finite element results will be used to locate strain gauges at high stress locations during prototype testing.

  19. Geochemistries of arsenic, antimony, mercury, and related elements in sediments of puget sound

    USGS Publications Warehouse

    Crecelius, E.A.; Bothner, Michael H.; Carpenter, R.

    1975-01-01

    The natural distributions of arsenic, antimony mercury, chromium, cobalt, iron, aluminum, and carbon in the surface sediments of Puget Sound are perturbed by two major anthropogenic sources of trace metals: a copper smelter near Tacoma, Wash., that discharges large amounts of arsenic and antimony, and a chlor-alkali plant in Bellingham, Wash., which, in the recent past, discharged significant amounts of mercury. Arsenic and antimony inputs from the smelter over the past 80 years are evident in sediment cores whose accumulation rates have been determined by the lead-210 technique. An arsenic budget for Puget Sound reveals the importance of atmospheric input resulting from smokestack emissions of the smelter. Chemical extraction studies of sediments showed that more than 82% of the mercury was associated with easily oxidizable organic matter, whereas about 50% of both arsenic and antimony was associated with extractable iron and aluminum compounds.

  20. Geochemistry of arsenic and other trace elements in a volcanic aquifer system of Kumamoto Area, Japan

    NASA Astrophysics Data System (ADS)

    Hossain, Shahadat; Hosono, Takahiro; Shimada, Jun

    2015-04-01

    Total arsenic (As), As(III) species, dissolved organic carbon (DOC), methane (CH4), sulfur isotope ratios of sulfate (δ34SSO4), major ions and trace elements were measured in groundwater collected from boreholes and wells along the flow lines of western margins of Kumamoto basin, at central part of Kyushu island in southern Japan. Kumamoto city is considered as the largest groundwater city in Japan. 100% people of this city depends on groundwater for their drinking purpose. In this study, we used trace elements data and δ34SSO4 values to better understand the processes that are likely controlling mobilization of As in this area. Arsenic concentrations ranges from 1 to 60.6 μg/L. High concentrations were found in both shallow and deep aquifers. The aquifers are composed of Quaternary volcanic (pyroclastic) flow deposits. In both aquifers, groundwaters evolve along the down flow gradient from oxidizing conditions of recharge area to the reducing conditions of stagnant area of Kumamoto plain. 40% samples from the Kumamoto plain area excced the maximum permissible limit of Japan drinking water quality standard (10 μg/L). In the reducing groundwater, As(III) constitutes typically more, however; 50% samples dominated with As(III) and 50% samples dominated with As(V) species. High As concentrations occur in anaerobic stagnant groundwaters from this plain area with high dissolved Fe, Mn, moderately dissolved HCO3, PO4, DOC and with very low concentrations of NO3 and SO4 suggesting the reducing condition of subsurface aquifer. Moderately positive correlation between As and dissolved Fe, Mn and strong negative correlation between As(III)/As(V) ratio and V, Cr and U reflect the dependence of As concentration on the reductive process. The wide range of δ34SSO4 values (6.8 to 36.1‰) indicate that sulfur is undergoing redox cycling. Highly enriched values suggesting the process was probably mediated by microbial activity. It also be noted from positive values of sulfur

  1. Fact Sheet on Arsenic

    EPA Pesticide Factsheets

    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.

  2. Radioactivity, granulometric and elemental analysis of river sediments samples from the coast of Calabria, south of Italy

    NASA Astrophysics Data System (ADS)

    Caridi, F.; D'Agostino, M.; Marguccio, S.; Belvedere, A.; Belmusto, G.; Marcianò, G.; Sabatino, G.; Mottese, A.

    2016-05-01

    River sediment samples from different sites of the coast of Calabria, south of Italy, were analyzed to determine the natural radioactivity concentration of the studied area and to investigate about their geological provenience. The radioactivity investigation was performed by using HPGe gamma spectrometry. Activity concentration data were reported and the influence of the particle size on the radionuclides concentration was investigated. X-ray fluorescence spectrometry (XRF) measurements were performed for the quantitative elemental analysis of the river sediments, revealing the major and minor elements present in the investigated samples. From XRF experimental results it was possible to estimate the geological provenience of the analyzed river sediments. Data obtained in this article provide useful information on the background radioactivity of the studied area and can be further used for radiological mapping of the coast of the Calabria rivers.

  3. Earth Abides Arsenic Biotransformations.

    PubMed

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

    2014-05-01

    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 is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice.

  4. Earth Abides Arsenic Biotransformations

    PubMed Central

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

    2015-01-01

    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 is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice. PMID:26778863

  5. Earth Abides Arsenic Biotransformations

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    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 is described. The article provides a comprehensive overview of molecular mechanisms of arsenic redox and methylation cycles as well as other arsenic biotransformations. It also discusses the implications of arsenic biotransformation in environmental remediation and food safety, with particular emphasis on groundwater arsenic contamination and arsenic accumulation in rice.

  6. Comparison of Barium and Arsenic Concentrations in Well Drinking Water and in Human Body Samples and a Novel Remediation System for These Elements in Well Drinking Water.

    PubMed

    Kato, Masashi; Kumasaka, Mayuko Y; Ohnuma, Shoko; Furuta, Akio; Kato, Yoko; Shekhar, Hossain U; Kojima, Michiyo; Koike, Yasuko; Dinh Thang, Nguyen; Ohgami, Nobutaka; Ly, Thuy Bich; Jia, Xiaofang; Yetti, Husna; Naito, Hisao; Ichihara, Gaku; Yajima, Ichiro

    2013-01-01

    Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L) and coexposure to barium (137 µg/L) and arsenic (225 µg/L). The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L) and barium (700 µg/L), but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium), in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system.

  7. Comparison of Barium and Arsenic Concentrations in Well Drinking Water and in Human Body Samples and a Novel Remediation System for These Elements in Well Drinking Water

    PubMed Central

    Kato, Masashi; Kumasaka, Mayuko Y.; Ohnuma, Shoko; Furuta, Akio; Kato, Yoko; Shekhar, Hossain U.; Kojima, Michiyo; Koike, Yasuko; Dinh Thang, Nguyen; Ohgami, Nobutaka; Ly, Thuy Bich; Jia, Xiaofang; Yetti, Husna; Naito, Hisao; Ichihara, Gaku; Yajima, Ichiro

    2013-01-01

    Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L) and coexposure to barium (137 µg/L) and arsenic (225 µg/L). The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L) and barium (700 µg/L), but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium), in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system. PMID:23805262

  8. Calculations of the moon's heat history at different concentrations of radioactive elements taking account of the material differentiation with melting

    NASA Technical Reports Server (NTRS)

    Arnatskaya, O. I.; Alber, Y. I.; Ryazantseva, I. L.

    1974-01-01

    A mathematical procedure for analyzing the heat conductivity of the lunar surface is discussed. The solution is based on homogeneous and laminated moon models and considers the effects of radioactive elements conveyed to the lunar surface by melting. The various parameters which introduce uncertainties into the numerical analysis are identified. The application of data obtained from radio astronomy and from analyses of lunar samples returned by the Apollo flights is explained. Tables of data are included to show the types and amounts of radioactive materials which have been identified.

  9. The concentrations of arsenic and other toxic elements in Bangladesh's drinking water.

    PubMed Central

    Frisbie, Seth H; Ortega, Richard; Maynard, Donald M; Sarkar, Bibudhendra

    2002-01-01

    For drinking water, the people of Bangladesh used to rely on surface water, which was often contaminated with bacteria causing diarrhea, cholera, typhoid, and other life-threatening diseases. To reduce the incidences of these diseases, millions of tubewells were installed in Bangladesh since independence in 1971. This recent transition from surface water to groundwater has significantly reduced deaths from waterborne pathogens; however, new evidence suggests disease and death from arsenic (As) and other toxic elements in groundwater are affecting large areas of Bangladesh. In this evaluation, the areal and vertical distribution of As and 29 other inorganic chemicals in groundwater were determined throughout Bangladesh. This study of 30 analytes per sample and 112 samples suggests that the most significant health risk from drinking Bangladesh's tubewell water is chronic As poisoning. The As concentration ranged from < 0.0007 to 0.64 mg/L, with 48% of samples above the 0.01 mg/L World Health Organization drinking water guideline. Furthermore, this study reveals unsafe levels of manganese (Mn), lead (Pb), nickel (Ni), and chromium (Cr). Our survey also suggests that groundwater with unsafe levels of As, Mn, Pb, Ni, and Cr may extend beyond Bangladesh's border into the four adjacent and densely populated states in India. In addition to the health risks from individual toxins, possible multimetal synergistic and inhibitory effects are discussed. Antimony was detected in 98% of the samples from this study and magnifies the toxic effects of As. In contrast, Se and Zn were below our detection limits in large parts of Bangladesh and prevent the toxic effects of As. PMID:12417487

  10. The concentrations of arsenic and other toxic elements in Bangladesh's drinking water.

    PubMed

    Frisbie, Seth H; Ortega, Richard; Maynard, Donald M; Sarkar, Bibudhendra

    2002-11-01

    For drinking water, the people of Bangladesh used to rely on surface water, which was often contaminated with bacteria causing diarrhea, cholera, typhoid, and other life-threatening diseases. To reduce the incidences of these diseases, millions of tubewells were installed in Bangladesh since independence in 1971. This recent transition from surface water to groundwater has significantly reduced deaths from waterborne pathogens; however, new evidence suggests disease and death from arsenic (As) and other toxic elements in groundwater are affecting large areas of Bangladesh. In this evaluation, the areal and vertical distribution of As and 29 other inorganic chemicals in groundwater were determined throughout Bangladesh. This study of 30 analytes per sample and 112 samples suggests that the most significant health risk from drinking Bangladesh's tubewell water is chronic As poisoning. The As concentration ranged from < 0.0007 to 0.64 mg/L, with 48% of samples above the 0.01 mg/L World Health Organization drinking water guideline. Furthermore, this study reveals unsafe levels of manganese (Mn), lead (Pb), nickel (Ni), and chromium (Cr). Our survey also suggests that groundwater with unsafe levels of As, Mn, Pb, Ni, and Cr may extend beyond Bangladesh's border into the four adjacent and densely populated states in India. In addition to the health risks from individual toxins, possible multimetal synergistic and inhibitory effects are discussed. Antimony was detected in 98% of the samples from this study and magnifies the toxic effects of As. In contrast, Se and Zn were below our detection limits in large parts of Bangladesh and prevent the toxic effects of As.

  11. Elements of natural radioactive decay series in Iranian drinking water and cigarettes.

    PubMed

    Mohammadi, Saeed

    2010-06-01

    The uranium (238U) decay series provides the most important isotopes of elements radium (226Ra), radon (222Rn), and polonium (210Po) with half-lives of about 1600 years, 3.8 days, and 140 days, respectively. Although the chemical structure of radium is very similar to calcium, the fact that it produces a radioactive gas (radon) complicates its handling in the laboratory and natural environment. In this study, we used the average concentrations of naturally occurring radionuclide 226Ra in drinking water at different parts of Iran to estimate the annual effective dose. In the other part of the study, we measured the concentrations of 210Po in Iranian cigarettes to estimate the internal intake of this radionuclide and its concentration in the lung tissues of smokers. The results indicate that the average concentration of 226Ra in Iranian drinking water was below the 100 mBq L(-1) recommended by the World Health Organization while the average concentration of 210Po and 210Pb in Iranian cigarettes was relatively high in comparison with other cigarettes found on the market.

  12. Cryptic exposure to arsenic.

    PubMed

    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.

  13. Identification and quantitation of arsenic species in a dogfish muscle reference material for trace elements

    SciTech Connect

    Beauchemin, D.; Bednas, M.E.; Berman, S.S.; McLaren, J.W.; Siu, K.W.M.; Sturgeon, R.E.

    1988-10-15

    The arsenic species present in a dogfish muscle reference material (DORM-1) have been identified by using high-performance liquid chromatography/inductively coupled plasma mass spectrometry (HPLC/ICP-MS), thin-layer chromatography, and electron impact mass spectrometry and quantified by using HPLC/ICP-MS and graphite furnace atomic absorption spectrometry. The major species is arsenobetaine (15.7 +/- 0.8 ..mu..g of As/g of DORM-1), constituting about 84% of the total arsenic. For this species, the HPLC/ICP-MS detection limit was 0.3 ng of As.

  14. Multi-trace elements level in drinking water and the prevalence of multi-chronic arsenical poisoning in residents in the west area of Iran.

    PubMed

    Barati, A H; Maleki, A; Alasvand, M

    2010-03-01

    First, we determined the levels of 8 trace elements (As, Se, Hg, Cd, Ag, Mn, Cr and Pb) in 530 village drinking water sources by graphite furnace or flame atomic absorption spectroscopy method, in Kurdistan Province in the west of Iran. The results showed that the level of As, Cd and Se in 28 village drinking water sources exceeded WHO or National Standard limits. The levels of concentration of arsenic in drinking water ranged from 42 to 1500microg/L. Then in a cross-sectional survey, 587 people from 211 households were chosen for clinical examinations of multi-chronic arsenical poisoning including pigment disorders, keratosis of palms and soles, Mee's line in fingers and nails and the gangrene as a systemic manifestation. Of 587 participants, 180 (30.7%) participants were affected by representing the type of chronic arsenical poisoning. The prevalence of Mee's line, keratosis, and pigment disorders were 86.1%, 77.2% and 67.8% respectively. Therefore, the prevalence of Mee's line between inhabitants was higher than the other disorders. The results show a strong linear relationship between arsenic exposure and occurrence of multi-chronic arsenical poisoning (R(2)=0.76). The association between age for more than 40 years and gender for more than 60 years with chronic arsenical poisoning is significant (p<0.05). Also, there is a relationship between subjects who were affected with disorders and duration of living in the village. Except for gangrene disorder, the odds ratio of prevalence of other disorders with arsenic exposure level in drinking water show a highly significant relationship between arsenic content and the risk of chronic disorders (p<0.01). These results confirm the need to further study trace elements in drinking waters, food products and other samples in this area and the relationship to other chronic diseases arising out of arsenicosis.

  15. [Determination of content and specific activity of radioactive elements in phosphate slag by spectral and energy spectrum analysis].

    PubMed

    Bao, P Y

    2001-10-01

    Phosphate slag is the slag discarded after phosphate ore is smelted. The content and specific activity of radioactive elements in slag must be determined accurately for environmental protection and comprehensive utilization. This paper discusses how IR spectrum and X-ray diffraction method are used to study its components. The main phase composition is glassy slag. The samples are decomposed with HF-HNO3-HClO4. After anion-exchange separation, arsenazo III is used to determine the content of uranium and thorium in slag. The average content of U is 32.11 micrograms.g-1 and 8.5 micrograms.g-1 for Th. gamma spectrum is used to determine the specific activity of radioactive nuclear elements in it. The specific activities of 226Ra, 232Th and 40K are 112 +/- 2.0% Bq.kg-1, 18.8 +/- 6.4% Bq.kg-1 and 77.6 +/- 3.7% Bq.kg-1, respectively. The values are calculated as follow: M(Ra) = 0.6 Bq.kg-1, M gamma = 0.5 Bq.kg-1. The results show that the values are below 1.0 Bq.kg-1, which is stipulated by national GB6566-86 standard for radioactivity of building materials. The slag is therefore can be utilized to produce slag cement. This provides theoretical basis for the treatment of it.

  16. Removal of mercury (II), elemental mercury and arsenic from simulated flue gas by ammonium sulphide.

    PubMed

    Ning, Ping; Guo, Xiaolong; Wang, Xueqian; Wang, Ping; Ma, Yixing; Lan, Yi

    2015-01-01

    A tubular resistance furnace was used as a reactor to simulate mercury and arsenic in smelter flue gases by heating mercury and arsenic compounds. The flue gas containing Hg(2+), Hg(0) and As was treated with ammonium sulphide. The experiment was conducted to investigate the effects of varying the concentration of ammonium sulphide, the pH value of ammonium sulphide, the temperature of ammonium sulphide, the presence of SO2 and the presence of sulphite ion on removal efficiency. The prepared adsorption products were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy. The results showed that the optimal concentration of ammonium sulphide was 0.8 mol/L. The optimal pH value of ammonium sulphide was 10, and the optimal temperature of ammonium sulphide was 20°C.Under the optimum conditions, the removal efficiency of Hg(2+), Hg(0) and As could reach 99%, 88.8%, 98%, respectively. In addition, SO2 and sulphite ion could reduce the removal efficiency of mercury and arsenic from simulated flue gas.

  17. Determination of toxic elements (mercury, cadmium, lead, tin and arsenic) in fish and shellfish samples. Risk assessment for the consumers.

    PubMed

    Olmedo, P; Pla, A; Hernández, A F; Barbier, F; Ayouni, L; Gil, F

    2013-09-01

    Although fish intake has potential health benefits, the presence of metal contamination in seafood has raised public health concerns. In this study, levels of mercury, cadmium, lead, tin and arsenic have been determined in fresh, canned and frozen fish and shellfish products and compared with the maximum levels currently in force. In a further step, potential human health risks for the consumers were assessed. A total of 485 samples of the 43 most frequently consumed fish and shellfish species in Andalusia (Southern Spain) were analyzed for their toxic elements content. High mercury concentrations were found in some predatory species (blue shark, cat shark, swordfish and tuna), although they were below the regulatory maximum levels. In the case of cadmium, bivalve mollusks such as canned clams and mussels presented higher concentrations than fish, but almost none of the samples analyzed exceeded the maximum levels. Lead concentrations were almost negligible with the exception of frozen common sole, which showed median levels above the legal limit. Tin levels in canned products were far below the maximum regulatory limit, indicating that no significant tin was transferred from the can. Arsenic concentrations were higher in crustaceans such as fresh and frozen shrimps. The risk assessment performed indicated that fish and shellfish products were safe for the average consumer, although a potential risk cannot be dismissed for regular or excessive consumers of particular fish species, such as tuna, swordfish, blue shark and cat shark (for mercury) and common sole (for lead).

  18. Thermal evolution of Earth's mantle and core: Influence of reference viscosity and concentration of radioactive elements in the mantle

    NASA Astrophysics Data System (ADS)

    Nakagawa, T.; Tackley, P. J.

    2010-12-01

    In a series of studies on the thermal evolution of Earth’s mantle and core [Nakagawa and Tackley, 2004; 2005; 2010], we have assumed a reference viscosity (at T=1600 K and P=0) of 1022 Pa.s and a concentration of radioactive elements based on the surface heat flux of the Earth’s mantle (6x10-12 W/kg). In addition, the initial mantle temperature in these studies was also based on the mantle adiabat estimated from present potential temperature (1600 K). Problems with these models are that (1) the average mantle temperature increases in the initial phase of the calculation and (2) the final (present-day) surface heat flux is a factor of two lower than expected from observational constraints (46 TW [Jaupart et al., 2007]), which means the Urey ratio is higher than the expected value (~0.3) [Jaupert et al., 2007; Korenaga, 2007]. Here we present results of a coupled model of thermo-chemical mantle convection in a 2-D spherical annulus and parameterized core heat balance, in which we vary (i) the reference viscosity down to 1020 Pa.s, giving a "surface" Rayleigh number of 109, (ii) the concentration of radioactive heat-producing elements in the mantle are tried (either a theoretical estimate [Schubert et al., 2001; 25 TW], geochemical estimate [McDonough and Sun, 1995; 20 TW] and modified geochemical estimate [Lyubetskaya and Korenaga, 2006; 16 TW]) and (iii) the initial mantle adiabat (up to 2500 K at the surface). Preliminary results indicate a preference for an initial mantle adiabat of more than 2500 K and the modified geochemical estimate of radioactive element concentration, in order to understand the current thermal state of Earth’s mantle when the reference viscosity is 1022 Pa s. Results with lower reference viscosity will be presented.

  19. Localization and speciation of arsenic and trace elements in rice tissues

    SciTech Connect

    Smith, Euan; Kempson, Ivan; Juhasz, Albert L.; Weber, John; Skinner, William M.; Gräfe, Markus

    2009-09-14

    The consumption of arsenic (As) contaminated rice is an important exposure route for humans in countries where rice cultivation employs As contaminated irrigation water. Arsenic toxicity and mobility are a function of its chemical-speciation. The distribution and identification of As in the rice plant are hence necessary to determine the uptake, transformation and potential risk posed by As contaminated rice. In this study we report on the distribution and chemical-speciation of As in rice (Oryza sativa Quest) by X-ray fluorescence (XRF) and X-ray absorption near edge structure (XANES) measurements of rice plants grown in As contaminated paddy water. Investigations of {mu}XRF images from rice tissues found that As was present in all rice tissues, and its presence correlated with the presence of iron at the root surface and copper in the rice leaf. X-ray absorption near edge structure analysis of rice tissues identified that inorganic As was the predominant form of As in all rice tissues studied, and that arsenite became increasingly dominant in the aerial portion of the rice plant.

  20. Arsenic cardiotoxicity: An overview.

    PubMed

    Alamolhodaei, Nafiseh Sadat; Shirani, Kobra; Karimi, Gholamreza

    2015-11-01

    Arsenic, a naturally ubiquitous element, is found in foods and environment. Cardiac dysfunction is one of the major causes of morbidity and mortality in the world. Arsenic exposure is associated with various cardiopathologic effects including ischemia, arrhythmia and heart failure. Possible mechanisms of arsenic cardiotoxicity include oxidative stress, DNA fragmentation, apoptosis and functional changes of ion channels. Several evidences have shown that mitochondrial disruption, caspase activation, MAPK signaling and p53 are the pathways for arsenic induced apoptosis. Arsenic trioxide is an effective and potent antitumor agent used in patients with acute promyelocytic leukemia and produces dramatic remissions. As2O3 administration has major limitations such as T wave changes, QT prolongation and sudden death in humans. In this review, we discuss the underlying pathobiology of arsenic cardiotoxicity and provide information about cardiac health effects associated with some medicinal plants in arsenic toxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Biochars mitigate greenhouse gas emissions and bioaccumulation of potentially toxic elements and arsenic speciation in Phaseolus vulgaris L.

    PubMed

    Ibrahim, Muhammad; Li, Gang; Khan, Sardar; Chi, Qiaoqiao; Xu, Yaoyang

    2017-07-05

    Anthropogenic and natural activities can lead to increased greenhouse gas emissions and discharge of potentially toxic elements (PTEs) into soil environment. Biochar amendment to soils is a cost-effective technology and sustainable approach used to mitigate greenhouse gas emissions, improve phytoremediation, and minimize the health risks associated with consumption of PTE-contaminated vegetables. Greenhouse pot experiments were conducted to investigate the effects of peanut shell biochar (PNB) and sewage sludge biochar (SSB) on greenhouse gas (GHG) emissions, plant growth, PTE bioaccumulation, and arsenic (As) speciation in bean plants. Results indicated that amendments of PNB and SSB increased plant biomass production by increasing soil fertility and reducing bioavailability of PTEs. Addition of biochars also increased soil pH, total nitrogen (TN), total carbon (TC), dissolved organic carbon (DOC), and ammonium-nitrogen (NH4-N) but decreased available concentrations of PTEs such as cadmium (Cd), lead (Pb), and As. The concentration of nitrate-nitrogen (NO3(-)-N) was also decreased in biochar-amended soils. In addition, PNB and SSB amendments significantly (P < 0.01) reduced the bioaccumulation of chromium (Cr), As, Cd, Pb, and nickel (Ni) in stalks, leaves, and fruits of Phaseolus vulgaris L. Similarly, PNB and SSB amendments significantly (P ≤ 0.05) reduced inorganic As species like arsenite (As (III)) and arsenate (As (V)). Greenhouse gases such as carbon dioxide (CO2) and methane (CH4) emissions were significantly (P < 0.01) reduced but nitrous oxide (N2O) emissions first increased and then decreased amended with both biochars. Current findings demonstrate that SSB and PNB are two beneficial soil amendments simultaneous mitigating greenhouse gas emissions and PTE bioaccumulation as well as arsenic speciation in P. vulgaris L.

  2. Arsenic pollution sources.

    PubMed

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

    2008-01-01

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

  3. Arsenic and other trace elements in groundwater and human urine in Ha Nam province, the Northern Vietnam: contamination characteristics and risk assessment.

    PubMed

    Pham, Long Hai; Nguyen, Hue Thi; Van Tran, Cuong; Nguyen, Ha Manh; Nguyen, Tung Hoang; Tu, Minh Binh

    2017-06-01

    The contamination characteristics of arsenic and other trace elements in groundwater and the potential risks of arsenic from the groundwater were investigated. Elevated contamination of arsenic, barium and manganese was observed in tube-well water of two villages (Chuyen Ngoai and Chau Giang) in Ha Nam province in the Northern Vietnam. Concentrations of As in the groundwater ranged from 12.8 to 884 µg/L with mean values in Chuyen Ngoai and Chau Giang were 614.7 and 160.1 µg/L, respectively. About 83 % of these samples contained As concentrations exceeding WHO drinking water guideline of 10 μg/L. The mean values of Mn and Ba in groundwater from Chuyen Ngoai and Chau Giang were 300 and 657 μg/L and 650 and 468 μg/L, respectively. The mean value of Ba concentration in groundwater in both Chuyen Ngoai and Chau Giang was about 22 % of the samples exceeded the WHO guideline (700 µg/L). Arsenic concentrations in human urine of residents from Chuyen Ngoai and Chau Giang were the range from 8.6 to 458 µg/L. The mean values of Mn and Ba in human urine of local people from Chuyen Ngoai were 46.9 and 62.8 μg/L, respectively, while those in people from Chau Giang were 25.9 and 45.9 μg/L, respectively. The average daily dose from ingesting arsenic for consuming both untreated and treated groundwater is from 0.02 to 11.5 and 0.003 to 1.6 μg/kg day, respectively. Approximately, 57 % of the families using treated groundwater and 64 % of the families using untreated groundwater could be affected by elevated arsenic exposure.

  4. Heat production rate from radioactive elements in igneous and metamorphic rocks in Eastern Desert, Egypt.

    PubMed

    Abbady, Adel G E; El-Arabi, A M; Abbady, A

    2006-01-01

    Radioactive heat-production data of Igneous and Metamorphic outcrops in the Eastern Desert are presented. Samples were analysed using a low level gamma-ray spectrometer (HPGe) in the laboratory. A total of 205 rock samples were investigated, covering all major rock types of the area. The heat-production rate of igneous rocks ranges from 0.11 (basalt) to 9.53 microWm(-3) (granite). In metamorphic rocks it varies from 0.28 (serpentinite ) to 0.91 microWm(-3) (metagabbro). The contribution due to U is about 51%, as that from Th is 31% and 18% from K. The corresponding values in igneous rocks are 76%, 19% and 5%, respectively. The calculated values showed good agreement with global values except in some areas containing granites.

  5. Design and adaptation of a novel supercritical extraction facility for operation in a glove box for recovery of radioactive elements

    SciTech Connect

    Kumar, V. Suresh; Kumar, R.; Sivaraman, N.; Ravisankar, G.; Vasudeva Rao, P. R.

    2010-09-15

    The design and development of a novel supercritical extraction experimental facility adapted for safe operation in a glove box for the recovery of radioactive elements from waste is described. The apparatus incorporates a high pressure extraction vessel, reciprocating pumps for delivering supercritical fluid and reagent, a back pressure regulator, and a collection chamber. All these components of the system have been specially designed for glove box adaptation and made modular to facilitate their replacement. Confinement of these materials must be ensured in a glove box to protect the operator and prevent contamination to the work area. Since handling of radioactive materials under high pressure (30 MPa) and temperature (up to 333 K) is involved in this process, the apparatus needs elaborate safety features in the design of the equipment, as well as modification of a standard glove box to accommodate the system. As a special safety feature to contain accidental leakage of carbon dioxide from the extraction vessel, a safety vessel has been specially designed and placed inside the glove box. The extraction vessel was enclosed in the safety vessel. The safety vessel was also incorporated with pressure sensing and controlling device.

  6. Extraction processes and solvents for recovery of cesium, strontium, rare earth elements, technetium and actinides from liquid radioactive waste

    DOEpatents

    Zaitsev, Boris N.; Esimantovskiy, Vyacheslav M.; Lazarev, Leonard N.; Dzekun, Evgeniy G.; Romanovskiy, Valeriy N.; Todd, Terry A.; Brewer, Ken N.; Herbst, Ronald S.; Law, Jack D.

    2001-01-01

    Cesium and strontium are extracted from aqueous acidic radioactive waste containing rare earth elements, technetium and actinides, by contacting the waste with a composition of a complex organoboron compound and polyethylene glycol in an organofluorine diluent mixture. In a preferred embodiment the complex organoboron compound is chlorinated cobalt dicarbollide, the polyethylene glycol has the formula RC.sub.6 H.sub.4 (OCH.sub.2 CH.sub.2).sub.n OH, and the organofluorine diluent is a mixture of bis-tetrafluoropropyl ether of diethylene glycol with at least one of bis-tetrafluoropropyl ether of ethylene glycol and bis-tetrafluoropropyl formal. The rare earths, technetium and the actinides (especially uranium, plutonium and americium), are extracted from the aqueous phase using a phosphine oxide in a hydrocarbon diluent, and reextracted from the resulting organic phase into an aqueous phase by using a suitable strip reagent.

  7. Natural radioactive elements and heavy metals in coal, fly ash and bottom ash from a thermal power plant

    SciTech Connect

    Font, J.; Casas, M.; Forteza, R.; Cerda, V.; Garcias, F. )

    1993-11-01

    The composition of coal used as fuel at a thermal power plant and those of the fly and bottom ashes it produces were determined. Radioactive elements were analysed for by alpha and gamma spectrometry, while sulphur, carbon and nitrogen were determined by burning. Heavy metals were quantified by X-ray fluorescence spectrometry and inductively coupled plasma atomic emission spectroscopy (ICPAES). The low sulphur content of the coal (0.68%) gives rise to fly ash containing only 0.21% of this element. The radiochemical analyses performed by alpha spectrometry revealed that most of the uranium remains in the solid residue resulting from disaggregation of the sample with Na[sub 2]CO[sub 3] in the separation process. Also, the gamma spectrometric results show that the elements from the 4n and 4n + 2 series and [sup 40]K concentrate in fly ash, the mean particle size of which is the smallest of all the residues assayed. 8 refs., 5 figs., 5 tabs.

  8. In Vivo Effect of Arsenic Trioxide on Keap1-p62-Nrf2 Signaling Pathway in Mouse Liver: Expression of Antioxidant Responsive Element-Driven Genes Related to Glutathione Metabolism

    PubMed Central

    Srivastava, Ritu; Sengupta, Archya; Mukherjee, Sandip; Chatterjee, Sarmishtha; Sudarshan, Muthammal; Chakraborty, Anindita; Bhattacharya, Shelley; Chattopadhyay, Ansuman

    2013-01-01

    Arsenic is a Group I human carcinogen, and chronic arsenic exposure through drinking water is a major threat to human population. Liver is one of the major organs for the detoxification of arsenic. The present study was carried out in mice in vivo after arsenic treatment through drinking water at different doses and time of exposure. Arsenic toxicity is found to be mediated by reactive oxygen species. Nuclear factor (erythroid-2 related) factor 2 (Nrf2)/Keap1 (Kelch-like ECH-associated protein 1)/ARE (antioxidant response element)—driven target gene system protects cells against oxidative stress and maintains cellular oxidative homeostasis. Our result showed 0.4 ppm, 2 ppm, and 4 ppm arsenic trioxide treatment through drinking water for 30 days and 90 days induced damages in the liver of Swiss albino mice as evidenced by histopathology, disturbances in liver function, induction of heat shock protein 70, modulation of trace elements, alteration in reduced glutathione level, glutathione-s-transferase and catalase activity, malondialdehyde production, and induction of apoptosis. Cellular Nrf2 protein level and mRNA level increased in all treatment groups. Keap1 protein as well as mRNA level decreased concomitantly in arsenic treated mice. Our study clearly indicates the important role of Nrf2 in activating ARE driven genes related to GSH metabolic pathway and also the adaptive response mechanisms in arsenic induced hepatotoxicity. PMID:27335833

  9. In Vivo Effect of Arsenic Trioxide on Keap1-p62-Nrf2 Signaling Pathway in Mouse Liver: Expression of Antioxidant Responsive Element-Driven Genes Related to Glutathione Metabolism.

    PubMed

    Srivastava, Ritu; Sengupta, Archya; Mukherjee, Sandip; Chatterjee, Sarmishtha; Sudarshan, Muthammal; Chakraborty, Anindita; Bhattacharya, Shelley; Chattopadhyay, Ansuman

    2013-01-01

    Arsenic is a Group I human carcinogen, and chronic arsenic exposure through drinking water is a major threat to human population. Liver is one of the major organs for the detoxification of arsenic. The present study was carried out in mice in vivo after arsenic treatment through drinking water at different doses and time of exposure. Arsenic toxicity is found to be mediated by reactive oxygen species. Nuclear factor (erythroid-2 related) factor 2 (Nrf2)/Keap1 (Kelch-like ECH-associated protein 1)/ARE (antioxidant response element)-driven target gene system protects cells against oxidative stress and maintains cellular oxidative homeostasis. Our result showed 0.4 ppm, 2 ppm, and 4 ppm arsenic trioxide treatment through drinking water for 30 days and 90 days induced damages in the liver of Swiss albino mice as evidenced by histopathology, disturbances in liver function, induction of heat shock protein 70, modulation of trace elements, alteration in reduced glutathione level, glutathione-s-transferase and catalase activity, malondialdehyde production, and induction of apoptosis. Cellular Nrf2 protein level and mRNA level increased in all treatment groups. Keap1 protein as well as mRNA level decreased concomitantly in arsenic treated mice. Our study clearly indicates the important role of Nrf2 in activating ARE driven genes related to GSH metabolic pathway and also the adaptive response mechanisms in arsenic induced hepatotoxicity.

  10. Radioactive resistance of elements for over-voltage protection of low-voltage systems

    NASA Astrophysics Data System (ADS)

    Osmokrovic, P.; Stojanovic, M.; Loncar, B.; Kartalovic, N.; Krivokapic, I.

    1998-04-01

    Aim of this work is to examine the over-voltage protection under the ionizing radiation influence. The use of modern electronic devices (nuclear, military and space technology) in the conditions of ionizing radiation brings up the question of radioactive resistance of electronic components and over-voltage protection components. The question of reliability of these components under the influence of ionizing radiation is also a relevant one. The entire effects of radiation, which cause the irreversible changes of the material characteristics, are defined as the dosage or integral effects. The resistance of the over-voltage material (the Transient Suppresser Diodes (TSD), Metaloxide Varistors, Gas Filled Surge Arresters (GFSA) and Polycarbon Capacitors) subjected to influence of n +γ radiation caused by californium source was examined in order to determine the radiation effects. It was determined that TSD are highly sensitive to the radiation. The radiation effects on Metaloxide Varistors are similar to the effects on the TSD. GFSA showed the temporary characteristics improvement. It was determined that the Polycarbon Capacitor capacity decreases under the influence of radiation. The obtained results are explained theoretically.

  11. Arsenic Exposure and Toxicology: A Historical Perspective

    PubMed Central

    Hughes, Michael F.; Beck, Barbara D.; Chen, Yu; Lewis, Ari S.; Thomas, David J.

    2011-01-01

    The metalloid arsenic is a natural environmental contaminant to which humans are routinely exposed in food, water, air, and soil. Arsenic has a long history of use as a homicidal agent, but in the past 100 years arsenic, has been used as a pesticide, a chemotherapeutic agent and a constituent of consumer products. In some areas of the world, high levels of arsenic are naturally present in drinking water and are a toxicological concern. There are several structural forms and oxidation states of arsenic because it forms alloys with metals and covalent bonds with hydrogen, oxygen, carbon, and other elements. Environmentally relevant forms of arsenic are inorganic and organic existing in the trivalent or pentavalent state. Metabolism of arsenic, catalyzed by arsenic (+3 oxidation state) methyltransferase, is a sequential process of reduction from pentavalency to trivalency followed by oxidative methylation back to pentavalency. Trivalent arsenic is generally more toxicologically potent than pentavalent arsenic. Acute effects of arsenic range from gastrointestinal distress to death. Depending on the dose, chronic arsenic exposure may affect several major organ systems. A major concern of ingested arsenic is cancer, primarily of skin, bladder, and lung. The mode of action of arsenic for its disease endpoints is currently under study. Two key areas are the interaction of trivalent arsenicals with sulfur in proteins and the ability of arsenic to generate oxidative stress. With advances in technology and the recent development of animal models for arsenic carcinogenicity, understanding of the toxicology of arsenic will continue to improve. PMID:21750349

  12. Constituent elements and their distribution in the radioactive Cs-bearing silicate glass microparticles released from Fukushima nuclear plant.

    PubMed

    Kogure, Toshihiro; Yamaguchi, Noriko; Segawa, Hiroyo; Mukai, Hiroki; Motai, Satoko; Akiyama-Hasegawa, Kotone; Mitome, Masanori; Hara, Toru; Yaita, Tsuyoshi

    2016-10-01

    Microparticles of radioactive cesium (Cs)-bearing silicate glass emitted from the Fukushima Daiichi nuclear power plant were investigated mainly using state-of-the-art energy-dispersive X-ray spectroscopy in scanning transmission electron microscopes. Precise elemental maps of the particles were obtained using double silicon drift detectors with a large collection angle of X-rays, and qualitative elemental analysis was performed using high-resolution X-ray spectroscopy with a microcalorimetry detector. Beside the substantial elements (O, Si, Cl, K, Fe, Zn, Rb, Sn and Cs) as previously reported, Mn and Ba were also common, though their amounts were small. The atomic ratios of the substantial elements were not the same but varied among individual particles. Fe and Zn were relatively homogeneously distributed, whereas the concentration of alkali ions varied radially. Generally, Cs was rich and K and Rb were poor outward of the particles but the degree of such radial dependence was considerably different among the particles. A concentration of Sn on the particle surface was observed. High-resolution imaging indicated the formation of SnO2 (cassiterite) nanocrystals on the surface. Synthesis of the bulk glass with a similar composition to the microparticles was attempted by quenching the silicate melt from ∼1600°C. However, homogeneous silicate glass like that of the microparticles could not be obtained due to the segregation of nano-spherules rich in Fe and Zn, suggesting that the microparticles were formed in a very specific condition in the nuclear reactor. © The Author 2016. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved.For permissions, please e-mail: journals.permissions@oup.com.

  13. Public Health Strategies for Western Bangladesh That Address Arsenic, Manganese, Uranium, and Other Toxic Elements in Drinking Water

    PubMed Central

    Frisbie, Seth H.; Mitchell, Erika J.; Mastera, Lawrence J.; Maynard, Donald M.; Yusuf, Ahmad Zaki; Siddiq, Mohammad Yusuf; Ortega, Richard; Dunn, Richard K.; Westerman, David S.; Bacquart, Thomas; Sarkar, Bibudhendra

    2009-01-01

    Background More than 60,000,000 Bangladeshis are drinking water with unsafe concentrations of one or more elements. Objectives Our aims in this study were to evaluate and improve the drinking water testing and treatment plans for western Bangladesh. Methods We sampled groundwater from four neighborhoods in western Bangladesh to determine the distributions of arsenic, boron, barium, chromium, iron, manganese, molybdenum, nickel, lead, antimony, selenium, uranium, and zinc, and to determine pH. Results The percentages of tube wells that had concentrations exceeding World Health Organization (WHO) health-based drinking water guidelines were 78% for Mn, 48% for U, 33% for As, 1% for Pb, 1% for Ni, and 1% for Cr. Individual tube wells often had unsafe concentrations of both Mn and As or both Mn and U. They seldom had unsafe concentrations of both As and U. Conclusions These results suggest that the ongoing program of identifying safe drinking water supplies by testing every tube well for As only will not ensure safe concentrations of Mn, U, Pb, Ni, Cr, and possibly other elements. To maximize efficiency, drinking water testing in Bangladesh should be completed in three steps: 1) all tube wells must be sampled and tested for As; 2) if a sample meets the WHO guideline for As, then it should be retested for Mn and U; 3) if a sample meets the WHO guidelines for As, Mn, and U, then it should be retested for B, Ba, Cr, Mo, Ni, and Pb. All safe tube wells should be considered for use as public drinking water supplies. PMID:19337516

  14. Arsenic, antimony, and other trace element contamination in a mine tailings affected area and uptake by tolerant plant species.

    PubMed

    Anawar, Hossain M; Freitas, M C; Canha, N; Santa Regina, I

    2011-08-01

    The study was conducted to characterize mineralogical and elemental composition of mine tailings in order to evaluate the environmental hazards, and identify the metal accumulation potential of native plant species from São Domingos mine, one of the long-term activity mines of the Iberian Pyrite Belt dating back to pre-Roman times. The mine tailings including soils and different plant species from São Domingos were analyzed for determination of tailings characteristics and chemical element contents in tailings and plants. The large amounts of mining wastes are causing significant adverse environment impacts due to acid mine drainage production and mobilization of potentially toxic metals and metalloids in residential areas, agricultural fields, downstreams, and rivers. The typical mineralogical composition is as follows: quartz, micas, K-feldspar, olivine-group minerals, magnetite, goethite, hematite, jarosite, and sulfides. The mine tailings were highly contaminated by As, Ag, Cr, Hg, Sn, Sb, Fe, and Zn; and among them, As and Sb, main contaminants, attained the highest concentrations except Fe. Arsenic has exhibited very good correlations with Au, Fe, Sb, Se, and W; and Sb with As, Au, Fe, Se, Sn, and W in tailings. Among the all plant species, the higher concentrations of all the metals were noted in Erica andevalensis, Erica australis, Echium plantagium, and Lavandula luisierra. Considering the tolerant behavior and abundant growth, the plant species Erica australis, Erica andevalensis, Lavandula luisierra, Daphne gnidium, Rumex induratus, Ulex eriocladus, Juncus, and Genista hirsutus are of major importance for the rehabilitation and recovery of degraded São Domingos mining area.

  15. Public health strategies for western Bangladesh that address arsenic, manganese, uranium, and other toxic elements in drinking water.

    PubMed

    Frisbie, Seth H; Mitchell, Erika J; Mastera, Lawrence J; Maynard, Donald M; Yusuf, Ahmad Zaki; Siddiq, Mohammad Yusuf; Ortega, Richard; Dunn, Richard K; Westerman, David S; Bacquart, Thomas; Sarkar, Bibudhendra

    2009-03-01

    More than 60,000,000 Bangladeshis are drinking water with unsafe concentrations of one or more elements. Our aims in this study were to evaluate and improve the drinking water testing and treatment plans for western Bangladesh. We sampled groundwater from four neighborhoods in western Bangladesh to determine the distributions of arsenic, boron, barium, chromium, iron, manganese, molybdenum, nickel, lead, antimony, selenium, uranium, and zinc, and to determine pH. The percentages of tube wells that had concentrations exceeding World Health Organization (WHO) health-based drinking water guidelines were 78% for Mn, 48% for U, 33% for As, 1% for Pb, 1% for Ni, and 1% for Cr. Individual tube wells often had unsafe concentrations of both Mn and As or both Mn and U. They seldom had unsafe concentrations of both As and U. These results suggest that the ongoing program of identifying safe drinking water supplies by testing every tube well for As only will not ensure safe concentrations of Mn, U, Pb, Ni, Cr, and possibly other elements. To maximize efficiency, drinking water testing in Bangladesh should be completed in three steps: 1) all tube wells must be sampled and tested for As; 2) if a sample meets the WHO guideline for As, then it should be retested for Mn and U; 3) if a sample meets the WHO guidelines for As, Mn, and U, then it should be retested for B, Ba, Cr, Mo, Ni, and Pb. All safe tube wells should be considered for use as public drinking water supplies.

  16. Monomethylated trivalent arsenic species disrupt steroid receptor interactions with their DNA response elements at non-cytotoxic cellular concentrations

    PubMed Central

    Gosse, Julie A.; Taylor, Vivien F.; Jackson, Brian P.; Hamilton, Joshua W.; Bodwell, Jack E.

    2013-01-01

    Arsenic (As) is considered a top environmental chemical of human health because it has been linked to adverse health effects including cancer, diabetes, cardiovascular disease, and reproductive and developmental problems. In several cell culture and animal models, As acts as an endocrine disruptor, which may underlie many of its health effects. Previous work showed that steroid receptor (SR)-driven gene expression is disrupted in cells treated with inorganic As (arsenite, iAs+3). In those studies, low iAs+3 concentrations (0.1–0.7 μM) stimulated hormone-inducible transcription, whereas somewhat higher but still non-cytotoxic levels (1–3 μM) inhibited transcription. This investigation focuses on the mechanisms underlying these inhibitory effects and evaluates the role of methylated trivalent As metabolites on SR function. Recent evidence suggests that, compared with iAs, methylated forms may have distinct biochemical effects. Here, fluorescence polarization (FP) experiments utilizing purified, hormone-bound human glucocorticoid (GR) and progesterone receptor (PR) have demonstrated that neither inorganic (iAs+3) nor dimethylated (DMA+3) species of trivalent As affect receptor interactions with glucocorticoid DNA response elements (GREs). However, monomethylated forms (monomethylarsenite, MMA+3 and monomethylarsonic diglutathione, MADG) strongly inhibit GR-GRE and PR-GRE binding. Additionally, speciation studies of iAs+3-treated H4IIE rat hepatoma cells show that, under treatment conditions that cause inhibition of hormone-inducible gene transcription, the intracellular concentration of MADG is sufficient to inhibit GR-GRE and PR-GRE interactions in vivo. These results indicate that arsenic’s inhibitory endocrine disruption effects are probably caused in part by methylated metabolites’ disruption of SR ability to bind DNA response elements that are crucial to hormone-driven gene transcription. PMID:23765520

  17. Characterization of regional cold-hydrothermal inflows enriched in arsenic and associated trace-elements in the southern part of the Duero Basin (Spain), by multivariate statistical analysis.

    PubMed

    Giménez-Forcada, Elena; Vega-Alegre, Marisol; Timón-Sánchez, Susana

    2017-09-01

    Naturally occurring arsenic in groundwater exceeding the limit for potability has been reported along the southern edge of the Cenozoic Duero Basin (CDB) near its contact with the Spanish Central System (SCS). In this area, spatial variability of arsenic is high, peaking at 241μg/L. Forty-seven percent of samples collected contained arsenic above the maximum allowable concentration for drinking water (10μg/L). Correlations of As with other hydrochemical variables were investigated using multivariate statistical analysis (Hierarchical Cluster Analysis, HCA and Principal Component Analysis, PCA). It was found that As, V, Cr and pH are closely related and that there were also close correlations with temperature and Na(+). The highest concentrations of arsenic and other associated Potentially Toxic Geogenic Trace Elements (PTGTE) are linked to alkaline NaHCO3 waters (pH≈9), moderate oxic conditions and temperatures of around 18°C-19°C. The most plausible hypothesis to explain the high arsenic concentrations is the contribution of deeper regional flows with a significant hydrothermal component (cold-hydrothermal waters), flowing through faults in the basement rock. Water mixing and water-rock interactions occur both in the fissured aquifer media (igneous and metasedimentary bedrock) and in the sedimentary environment of the CDB, where agricultural pollution phenomena are also active. A combination of multivariate statistical tools and hydrochemical analysis enabled the distribution pattern of dissolved As and other PTGTE in groundwaters in the study area to be interpreted, and their most likely origin to be established. This methodology could be applied to other sedimentary areas with similar characteristics and problems. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Calculations of the moon's thermal history at different concentrations of radioactive elements, taking into account differentiation on melting

    NASA Technical Reports Server (NTRS)

    Ornatskaya, O. I.; Alber, Y. I.; Ryazantseva, I. L.

    1977-01-01

    Calculations of the thermal history of the moon were done by solving the thermal conductivity equation for the case in which the heat sources are the long lived radioactive elements Th, U, and K-40. The concentrations of these elements were adjusted to give 4 variations of heat flow. Calculations indicated that the moon's interior was heated to melting during the first 0.7 to 2.3 x 10 to the 9th power years. The maximum fusion involved practically the entire moon to a distance from 15 to 45 km beneath the surface, and started 3.5 to 4.0 x 10 to the 9th power years ago, or 2.5 x 3.0 x 10 to the 9th power years ago and continued for 1 to 2 x 10 to the 9th power years. The moon today is cooling. The current thickness of the solid crust is from 150 to 200 km and the heat flow exceeds the stationary value 1.5 fold.

  19. Solid Phase Biosensors for Arsenic or Cadmium Composed of A trans Factor and cis Element Complex

    PubMed Central

    Siddiki, Mohammad Shohel Rana; Kawakami, Yasunari; Ueda, Shunsaku; Maeda, Isamu

    2011-01-01

    The presence of toxic metals in drinking water has hazardous effects on human health. This study was conducted to develop GFP-based-metal-binding biosensors for on-site assay of toxic metal ions. GFP-tagged ArsR and CadC proteins bound to a cis element, and lost the capability of binding to it in their As- and Cd-binding conformational states, respectively. Water samples containing toxic metals were incubated on a complex of GFP-tagged ArsR or CadC and cis element which was immobilized on a solid surface. Metal concentrations were quantified with fluorescence intensity of the metal-binding states released from the cis element. Fluorescence intensity obtained with the assay significantly increased with increasing concentrations of toxic metals. Detection limits of 1 μg/L for Cd(II) and 5 μg/L for As(III) in purified water and 10 µg/L for Cd(II) and As(III) in tap water and bottled mineral water were achieved by measurement with a battery-powered portable fluorometer after 15-min and 30-min incubation, respectively. A complex of freeze dried GFP-tagged ArsR or CadC binding to cis element was stable at 4 °C and responded to 5 μg/L As(III) or Cd(II). The solid phase biosensors are sensitive, less time-consuming, portable, and could offer a protocol for on-site evaluation of the toxic metals in drinking water. PMID:22346629

  20. Arsenic and trace elements in soil, water, grapevine and onion in Jáchal, Argentina.

    PubMed

    Funes Pinter, Iván; Salomon, M Victoria; Gil, Raúl; Mastrantonio, Leandro; Bottini, Rubén; Piccoli, Patricia

    2017-09-16

    Contamination by trace elements (TE) is an increasing concern worldwide. In some areas, crop production could be limited by the presence of metals and metalloids, so it is important to determine their concentrations and mobility. The region of Jáchal, province of San Juan, Argentina, has good growing conditions for onion and grapevine production, but their quality and yield are affected by high TE concentration in soils and water. Soils, water, grapevine and onion were sampled and TE content determined. In soils elevated As, B, Cr, Hg, and Tl concentrations were detected (506±46, 149±3, 2714±217, 16±7, and 12±3μgg(-1), respectively, for maximum values measured), and physicochemical properties of the soil promotes these elements mobility. Water samples had high As, B, Cr, and Fe concentrations (1438±400, 10,871±471, 11,516±2363, and 3071±257μgL(-1), respectively, for maximum values measured) while in onion bulbs and grapevine berries, As, Cr, Cu, and Fe (92±7 and 171±20, 1412±18 and 2965±32, 17±3 and 126±88, and 418±204 and 377±213μgg(-1), respectively, for maximum values measured) exceeded the limits for food consumption established by Argentinian law. Correlation analyses indicated that: i) there is a common source of TE in this area, ii) each elements concentration in plants is associated with different soil variables and different soils depths, and iii) the lack of correlation between soil and water indicates that concentration in water is not constant over the time and/or there exists a differential accumulation of elements in soils depending on their own properties. Data obtained demonstrate very high concentration of TE in soil, grapevines, and onion plants in Jáchal region, and different remediation techniques are necessary to stabilize and minimize the bioavailability of these elements. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Extinct radioactivities and protosolar cosmic-rays : self-shielding and light elements.

    SciTech Connect

    Gounelle, M.; Shu, F. H.; Shang, H.; Glassgold, A. E.; Rehm, K. E.; Lee, T.; Physics; Univ. of California at Berkeley; Inst. of Earth Science

    2001-02-20

    We study the effects of self-shielding in the X-wind model of protosolar cosmic-ray irradiation of early solar-system rocks. We adopt a two-component picture of protoCAIs consisting of cores with the elemental abundances of type B1 CAIs (calcium-aluminum-rich inclusions) and mantles of less refractory material. The cores have a power-law distribution of sizes between R{sub min} and R{sub max}. The mantles have a uniform thickness, whose value is chosen to bring the total inventory of elements at least as refractory as sulfur to cosmic abundances for the entire population of protoCAIs. Each object is irradiated with a fluence consistent with the product of their residence time in the reconnection ring and the flux of solar cosmic rays obtained by a scaling of impulsive flares from the hard X-rays observed from low-mass protostars. For R{sub min} in the 50 {mu}m regime and R{sub max} in the few centimeter regime, which corresponds to the range of sizes of observed CAIs in micrometeorites and chondrites, we recover approximately the canonical values quoted for the ratios {sup 26}Al/{sup 27}Al, {sup 53}Mn/{sup 55}Mn, and {sup 41}Ca/{sup 40}Ca in CV3 meteorites. Moreover, the excess {sup 138}La (denoted as {sup 138}La*) produced by proton bombardment of {sup 138}Ba lies within the CAI range obtained in the experiments of Shen et al. When we include fragmentation reactions that produce {sup 10}Be from the impact of protons, alphas, and {sup 3}He on the {sup 16}O that is bound up in rocks, we further obtain a level of {sup 10}Be/{sup 9}Be that agrees approximately with the report of McKeegan et al. for a CAI from the Allende meteorite. Similar calculations for the expected anomalies in the stable isotopes of lithium show rough consistency with the measured values and further support our interpretation. The value for {sup 10}Be/{sup 9}Be is particularly difficult to produce by any other astrophysical mechanism. Thus, the {sup 10}Be discovery greatly strengthens the case

  2. Natural contamination with arsenic and other trace elements in groundwater of the Central-West region of Chaco, Argentina.

    PubMed

    Blanes, Patricia S; Buchhamer, Edgar E; Giménez, María C

    2011-01-01

    This study covered the central agricultural region of the Chaco province, which lacks a permanent river networks. However, during the rainy period there is localized groundwater recharge. About 84 groundwater samples were taken during the period April-December 2007. These groundwater samples were collected from two different depths: 62 samples from shallow wells (4 to 20 m) and 24 samples from deep wells (20 to 100 m). Chemical variables were determined: pH, specific conductance, total dissolved solid, hardness, alkalinity, HCO(3)-, CO(3)(2-), SO(4)(2-), Cl-, NO(3)-, NO(2) -, NH(4)+, F-, As((tot)), Na+, K+, Ca2+, Mg2+, Fe, Cu, Ni, Pb and Zn. The chemical composition of groundwater in the study area is dominantly sodium bicarbonate and sodium chloride bicarbonate, comprising more than 60% (52/86) of shallow and deep groundwater samples. Of the 86 analyzed groundwater samples, 88% exceeded the WHO (World Health Organization) and CAA (Código Alimentario Argentino) standards (10 μg/L) for As (arsenic) and 9% exceeded the WHO standard (1.5 mg/L) for F(-).Groundwater highly contaminated with As (max. 1,073 μg/L) and F- (max. 4.2 mg/L) was found in shallow aquifer. The contaminated groundwater is characterized by high pH (max. 8.9), alkalinity (max. HCO(3)- 1,932 mg/L), SO(4)(2-) (max. 11,862 mg/L), Na(+) (max. 3,158 mg/L), Cl(-) (max. 10,493 mg/L) and electric conductivity greater than 33.3 μS/cm. Other associated elements (Ni, Pb, Cu and Zn) are present in low concentrations, except for Fe that in 32% of samples exceeded the guideline value of 0.3 mg/L suggested by the CAA.

  3. A METHOD FOR DETERMINING TOTAL PROTEIN OF ISOLATED CELLULAR ELEMENTS AND CORRESPONDING TRITIUM RADIOACTIVITY

    PubMed Central

    Koenig, Edward

    1968-01-01

    A method is described for the microanalysis of protein, obtained from isolated tissue elements, in the range of 500 µµg-500 mµg. The method entails solubilization of cellular protein with phosphoric acid and heat after extraction of acid-soluble compounds, lipids, and RNA. A procedure for the extraction and recovery of cellular RNA by the use of 40% trichloroacetic acid is presented. The solubilized protein, in the form of a microdroplet, is photomicrographed with monochromatic light at 230 mµ. Total density in the microdroplet is determined from calibrated photographic plates by microdensitometry, and is converted to protein mass by using an experimentally determined average specific absorbance value. A solubilized protein labeled with tritium can be recovered after photomicrography, combusted, and reduced to generate tritiated gas for high-efficiency tritium radiometry. Total protein was analyzed in (a) nerve cells of three different sizes from Deiters' nucleus of the rabbit; and the whole rod cell and rod cell nucleus of the rabbit retina. PMID:5664225

  4. Physical simulation of precipitation of radioactive element oxalates by using the harmless neodymium oxalate for studying the agglomeration phenomena

    NASA Astrophysics Data System (ADS)

    Lalleman, Sophie; Bertrand, Murielle; Plasari, Edouard

    2012-03-01

    Oxalic precipitation is usually applied in nuclear industry to process radioactive wastes or to recover actinides from a multicomponent solution. This paper deals with the development of methods adapted to a nuclear environment in order to study the agglomeration phenomena during actinide oxalic precipitation. These methods are previously setup with harmless elements that simulate the actinide behaviour: the lanthanides. A parametric study is carried out to quantify the influence of operating parameters on the agglomeration kernel and to determine a kinetic law for this mechanism. The experimental study is performed in a continuous-MSMPR precipitator at steady-state. The method is based on the resolution of two population balances using the moment approach, one for elementary crystals and the other for agglomerates. Provided that the kinetic rates of nucleation and growth are known, the agglomeration kernel can be obtained from a mathematical treatment of the experimental particle size distributions. Results point out that experimental crystal sizes are consistent with an independent kernel. It appears that the agglomeration kernel is directly proportional to supersaturation, increases with temperature but is limited by ionic strength and shear rate.

  5. Physical property analysis of C-doped GaAs as function of the carrier concentration grown by MOCVD using elemental arsenic as precursor

    NASA Astrophysics Data System (ADS)

    Díaz-Reyes, J.; Avendaño, M. A.; Galván-Arellano, M.; Peña-Sierra, R.

    2006-03-01

    This work presents the characterization of GaAs layers grown in a metallic-arsenic-based-MOCVD system. The gallium precursor was the compound trimethylgallium (TMG) and elemental arsenic as precursor of arsenic. The most important parameters of the growth process include the substrate temperature and the composition of the carrier gas; an N2+H2 gas mixture. The influence of carbon doping on the optical and electrical properties of GaAs layers have been studied by photoluminescence (PL) spectroscopy, Photoreflectance (PR) and Hall Effect measurements. To carry out doping with carbon in the range of around 1016 to 1020 cm-3, it was necessary to modifying the hydrogen activity in the reacting atmosphere with the control of the N{2}+H{2}, mixture which was used as carrier gas. The PL response of the samples is strongly dependent on the growth temperature and showed mainly two radiative transitions, band-to-band and band-to C-acceptor. PR spectra present transitions associated to GaAs. Besides, short period oscillations near the GaAs band-gap energy are observed, interpreted as Franz-Keldysh oscillations associated to the hole-ionized acceptor (h-A-) pair modulations. For investigating the chemical bonds of impurity-related species in the GaAs layers optical absorption was measured using a FT-IR spectrometer. Device quality GaAs layers have been grown in a broad range of growth temperatures.

  6. Geochemistry of redox-sensitive elements and sulfur isotopes in the high arsenic groundwater system of Datong Basin, China.

    PubMed

    Xie, Xianjun; Ellis, Andre; Wang, Yanxin; Xie, Zuoming; Duan, Mengyu; Su, Chunli

    2009-06-01

    High arsenic groundwater in the Quaternary aquifers of Datong Basin, northern China contain As up to 1820 microg/L and the high concentration plume is located in the slow flowing central parts of the basin. In this study we used hydrochemical data and sulfur isotope ratios of sulfate to better understand the conditions that are likely to control arsenic mobilization. Groundwater and spring samples were collected along two flow paths from the west and east margins of the basin and a third set along the basin flow path. Arsenic concentrations range from 68 to 670 microg/L in the basin and from 3.1 to 44 microg/L in the western and eastern margins. The margins have relatively oxidized waters with low contents of arsenic, relatively high proportions of As(V) among As species, and high contents of sulfate and uranium. By contrast, the central parts of the basin are reducing with high contents of arsenic in groundwater, commonly with high proportions of As(III) among As species, and low contents of sulfate and uranium. No statistical correlations were observed between arsenic and Eh, sulfate, Fe, Mn, Mo and U. While the mobility of sulfate, uranium and molybdenum is possibly controlled by the change in redox conditions as the groundwater flows towards central parts of the basin, the reducing conditions alone cannot account for the occurrence of high arsenic groundwater in the basin but it does explain the characteristics of arsenic speciation. With one exception, all the groundwaters with As(III) as the major As species have low Eh and those with As(V) have high Eh. Reductive dissolution of Fe-oxyhydroxides or reduction of As(V) are consistent with the observations, however no increase in dissolved Fe concentration was noted. Furthermore, water from the well with the highest arsenic was relatively oxidizing and contained mostly As(V). From previous work Fe-oxyhydroxides are speculated to exist as coatings rather than primary minerals. The wide range of delta(34)S([SO4

  7. Arsenic and other trace elements in thermal springs and in cold waters from drinking water wells on the Bolivian Altiplano

    NASA Astrophysics Data System (ADS)

    Ormachea Muñoz, Mauricio; Bhattacharya, Prosun; Sracek, Ondra; Ramos Ramos, Oswaldo; Quintanilla Aguirre, Jorge; Bundschuh, Jochen; Maity, Jyoti Prakash

    2015-07-01

    Numerous hot springs and fumaroles occur along the Andes Mountains, in the Bolivian Altiplano, where people use thermal springs for recreational purposes as pools, baths and also for consumption as drinking water and irrigation once it is mixed with natural surface waters; most of these thermal springs emerge from earth surface and flow naturally into the rivers streams which drain further into the Poopó Lake. Physicochemical characteristics of the thermal water samples showed pH from 6.3 to 8.3 with an average of 7.0, redox potential from +106 to +204 mV with an average of +172 mV, temperatures from 40 to 75 °C with an average of 56 °C and high electrical conductivity ranging from 1.8 to 75 mS/cm and averaged 13 mS/cm. Predominant major ions are Na+ and Cl- and the principal water types are 37.5% Na-Cl type and 37.5% Na-Cl-HCO3 type. Arsenic concentrations ranged from 7.8 to 65.3 μg/L and arsenic speciation indicate the predominance of As(III) species. Sediments collected from the outlets of thermal waters show high iron content, and ferric oxides and hydroxides are assumed to be principal mineral phases for arsenic attenuation by adsorption/co-precipitation processes. Arsenic concentrations in cold water samples from shallow aquifers are higher than those in thermal springs (range < 5.6-233.2 μg/L), it is likely that thermal water discharge is not the main source of high arsenic content in the shallow aquifer as they are very immature and may only have a small component corresponding to the deep geothermal reservoir. As people use both thermal waters and cold waters for consumption, there is a high risk for arsenic exposure in the area.

  8. Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyticus. I. Stoichiometry with compounds of arsenic, selenium, tellurium, transition and other elements.

    PubMed

    WOOLFOLK, C A; WHITELEY, H R

    1962-10-01

    Woolfolk, C. A. (University of Washington, Seattle) and H. R. Whiteley. Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyticus. I. Stoichiometry with compounds of arsenic, selenium, tellurium, transition and other elements. J. Bacteriol. 84:647-658. 1962.-Extracts of Micrococcus lactilyticus (Veillonella alcalescens) oxidize molecular hydrogen at the expense of certain compounds of arsenic, bismuth, selenium, tellurium, lead, thallium, vanadium, manganese, iron, copper, molybdenum, tungsten, osmium, ruthenium, gold, silver, and uranium, as well as molecular oxygen. Chemical and manometric data indicate that the following reductions are essentially quantitative: arsenate to arsenite, pentavalent and trivalent bismuth to the free element, selenite via elemental selenium to selenide, tellurate and tellurite to tellurium, lead dioxide and manganese dioxide to the divalent state, ferric to ferrous iron, osmium tetroxide to osmate ion, osmium dioxide and trivalent osmium to the metal, uranyl uranium to the tetravalent state, vanadate to the level of vanadyl, and polymolybdate ions to molybdenum blues with an average valence for molybdenum of +5. The results of a study of certain other hydrogenase-containing bacteria with respect to their ability to carry out some of the same reactions are also presented.

  9. Arsenic induces NAD(P)H-quinone oxidoreductase I by disrupting the Nrf2 x Keap1 x Cul3 complex and recruiting Nrf2 x Maf to the antioxidant response element enhancer.

    PubMed

    He, Xiaoqing; Chen, Michael G; Lin, Gary X; Ma, Qiang

    2006-08-18

    The ubiquitous toxic metalloid arsenic elicits pleiotropic adverse and adaptive responses in mammalian species. The biological targets of arsenic are largely unknown at present. We analyzed the signaling pathway for induction of detoxification gene NAD(P)H-quinone oxidoreductase (Nqo1) by arsenic. Genetic and biochemical evidence revealed that induction required cap 'n' collar basic leucine zipper transcription factor Nrf2 and the antioxidant response element (ARE) of Nqo1. Arsenic stabilized Nrf2 protein, extending the t(1/2) of Nrf2 from 21 to 200 min by inhibiting the Keap1 x Cul3-dependent ubiquitination and proteasomal turnover of Nrf2. Arsenic markedly inhibited the ubiquitination of Nrf2 but did not disrupt the Nrf2 x Keap1 x Cul3 association in the cytoplasm. In the nucleus, arsenic, but not phenolic antioxidant tert-butylhydroquinone, dissociated Nrf2 from Keap1 and Cul3 followed by dimerization of Nrf2 with a Maf protein (Maf G/Maf K). Chromatin immunoprecipitation demonstrated that Nrf2 and Maf associated with the endogenous Nqo1 ARE enhancer constitutively. Arsenic substantially increased the ARE occupancy by Nrf2 and Maf. In addition, Keap1 was shown to be ubiquitinated in the cytoplasm and deubiquitinated in the nucleus in the presence of arsenic without changing the protein level, implicating nuclear-cytoplasmic recycling of Keap1. Our data reveal that arsenic activates the Nrf2/Keap1 signaling pathway through a distinct mechanism from that by antioxidants and suggest an "on-switch" model of Nqo1 transcription in which the binding of Nrf2 x Maf to ARE controls both the basal and inducible expression of Nqo1.

  10. High mobilization of arsenic, metals and rare earth elements in seepage waters driven by respiration of old allochthonous organic carbon.

    PubMed

    Weiske, Arndt; Schaller, Jörg; Hegewald, Tilo; Machill, Susanne; Werner, Ingo; Dudel, E Gert

    2013-12-01

    Metal and metalloid mobilization processes within seepage water are of major concern in a range of water reservoir systems. The mobilization process of arsenic and heavy metals within a dam and sediments of a drinking water reservoir was investigated. Principle component analysis (PCA) on time series data of seepage water showed a clear positive correlation of arsenic with iron and DOC (dissolved organic carbon), and a negative correlation with nitrate due to respiratory processes. A relationship of reductive metal and metalloid mobilization with respiration of old carbon was shown. The system is influenced by sediment layers as well as a recent DOC input from degraded ombrotrophic peatbogs in the catchment area. The isotopic composition ((12)C, (13)C and (14)C) of DOC is altered along the path from basin to seepage water, but no significant changes in structural parameters (LC-OCD-OND, FT-IR) could be seen. DIC (dissolved inorganic carbon) in seepage water partly originates from respiratory processes, and a higher relationship of it with sediment carbon than with the DOC inventory of infiltrating water was found. This study revealed the interaction of respiratory processes with metal and metalloid mobilization in sediment water flows. In contrast to the presumption that emerging DOC via respiratory processes mainly controls arsenic and metal mobilization it could be shown that the presence of aged carbon compounds is essential. The findings emphasize the importance of aged organic carbon for DOC, DIC, arsenic and metal turnover.

  11. Effect of long-term administration of arsenic (III) and bromine with and without selenium and iodine supplementation on the element level in the thyroid of rat.

    PubMed

    Kotyzová, Dana; Eybl, Vladislav; Mihaljevic, Martin; Glattre, Eystein

    2005-12-01

    The aim of this study was to evaluate the influence of arsenic and bromine exposure with or without iodine and selenium supplementation on the element level in the thyroid of rats. Four major groups of Wistar female rats were fed with respective diets: group A - standard diet, group B - iodine rich diet (10 mg I/kg food), group C - selenium rich diet (1 mg Se/kg) and group D - iodine and selenium rich diet (as in group B and C). Each group was divided into four subgroups per 7 animals each receiving either NaAsO(2) ip (6.5 mg.kg(-1) twice a week for two weeks and 3.25 mg.kg(-1) for six weeks) or KBr in drinking water (58.8 mg.l(-1)) for 8 weeks or combined administration of both substances. Remaining subgroup served as controls. After 8 weeks thyroid glands were analyzed by ICP-MS for As, Br, Se, and I content. The exposition of rat to arsenic or bromine causes the accumulation of these elements in the thyroid gland ( approximately 18 ppm of As, approximately 90 ppm of Br) and significantly affects iodine and selenium concentration in the thyroid. In iodine and/or selenium supplemented rats the bromine intake into the thyroid was lowered to approximately 50% of the level in unsupplemented animals. Also selenium thyroid level elevated due to KBr administration was lowered by iodine supplementation in the diet. The accumulation of arsenic in the thyroid was not influenced by selenium or iodine supplementation; however, As(III) administration increased iodine thyroid level and suppressed selenium thyroid level in selenium or iodine supplemented group of animals.

  12. Total Mercury, Methylmercury, Inorganic Arsenic and Other Elements in Meat from Minke Whale (Balaenoptera acutorostrata) from the North East Atlantic Ocean.

    PubMed

    Maage, Amund; Nilsen, Bente M; Julshamn, Kaare; Frøyland, Livar; Valdersnes, Stig

    2017-08-01

    Meat samples of 84 minke whales (Balaenoptera acutorostrata) mainly from the Barents Sea, collected between 1 May and 16 August 2011, were analyzed for total mercury, methylmercury, cadmium, lead, total arsenic, inorganic arsenic and selenium. The average total mercury concentration found was 0.15 ± 0.09 mg/kg, with a range from 0.05 to 0.49 mg/kg. The molar ratio of selenium to mercury varied between 1.0 and 10.3. Cadmium content ranged from 0.002 to 0.036 mg/kg, while the content of lead in whale meat ranged from <0.01 to 0.09 mg/kg. None of the whale samples exceeded established EU maximum levels for metals in fish muscle, but 4.8% and 6.8% of the samples exceeded Japanese maximum levels for total mercury and methylmercury, respectively, in whale meat. There was only minor variations in element concentrations between whales from different geographical areas, and cadmium was the only element were the concentration increased with increasing length.

  13. Arsenic poisoning in dairy cattle from naturally occurring arsenic pyrites.

    PubMed

    Hopkirk, R G

    1987-10-01

    An outbreak of arsenic poisoning occurred in which most of a 200 cow dairy herd were affected and six died. The source of the arsenic was naturally occurring arsenic pyrites from the Waiotapu Stream, near Rotorua. Arsenic levels in the nearby soil were as high as 6618 ppm. There was little evidence to suggest that treatment affected the course of the disease. Haematology was of little use in diagnosis, post-mortem signs were not always consistent and persistence of the element in the liver appeared short. Control of further outbreaks have been based on practical measures to minimise the intake of contaminated soil and free laying water by the stock.

  14. Arsenic Methyltransferase

    EPA Science Inventory

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

  15. Arsenic Methyltransferase

    EPA Science Inventory

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

  16. Ultra-Sensitive Elemental Analysis Using Plasmas 5.Speciation of Arsenic Compounds in Biological Samples by High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry System

    NASA Astrophysics Data System (ADS)

    Kaise, Toshikazu

    Arsenic originating from the lithosphere is widely distributed in the environment. Many arsenicals in the environment are in organic and methylated species. These arsenic compounds in drinking water or food products of marine origin are absorbed in human digestive tracts, metabolized in the human body, and excreted viatheurine. Because arsenic shows varying biological a spects depending on its chemical species, the biological characteristics of arsenic must be determined. It is thought that some metabolic pathways for arsenic and some arsenic circulation exist in aqueous ecosystems. In this paper, the current status of the speciation analysis of arsenic by HPLC/ICP-MS (High Performance Liquid Chromatography-Inductively Coupled Plasma Mass spectrometry) in environmental and biological samples is summarized using recent data.

  17. BEHAVIOR OF ARSENIC AND OTHER REDOX-SENSITIVE ELEMENTS IN CROWLEY LAKE, CA: A RESERVOIR IN THE LOS ANGELES AQUEDUCT SYSTEM. (R826202)

    EPA Science Inventory

    Elevated arsenic concentrations in Crowley Lake derive from upstream geothermal inputs. We examined the water column of Crowley Lake under stratified and unstratified conditions, seeking evidence for algal uptake and transformation of arsenic and its deposition to and release fro...

  18. BEHAVIOR OF ARSENIC AND OTHER REDOX-SENSITIVE ELEMENTS IN CROWLEY LAKE, CA: A RESERVOIR IN THE LOS ANGELES AQUEDUCT SYSTEM. (R826202)

    EPA Science Inventory

    Elevated arsenic concentrations in Crowley Lake derive from upstream geothermal inputs. We examined the water column of Crowley Lake under stratified and unstratified conditions, seeking evidence for algal uptake and transformation of arsenic and its deposition to and release fro...

  19. ARSENIC REMOVAL

    EPA Science Inventory

    Presentation covered five topics; arsenic chemistry, best available technology (BAT), surface water technology, ground water technology and case studies of arsenic removal. The discussion on arsenic chemistry focused on the need and method of speciation for AsIII and AsV. BAT me...

  20. Spatially resolved elemental mapping of two U.S. rice core collection grain accessions with diverse arsenic accumulation characteristics via synchrotron x-Ray fluorescence microscopy (SXRF)

    USDA-ARS?s Scientific Manuscript database

    The discovery of arsenic in higher than expected concentrations in rice grown in the South Central United States and worldwide has prompted further study to ensure the safety of rice, and rice based products such as infant cereals. In the U.S. arsenic is thought to originate from former arsenical pe...

  1. Spatial gradient of human health risk from exposure to trace elements and radioactive pollutants in soils at the Puchuncaví-Ventanas industrial complex, Chile.

    PubMed

    Salmani-Ghabeshi, S; Palomo-Marín, M R; Bernalte, E; Rueda-Holgado, F; Miró-Rodríguez, C; Cereceda-Balic, F; Fadic, X; Vidal, V; Funes, M; Pinilla-Gil, E

    2016-11-01

    The Punchuncaví Valley in central Chile, heavily affected by a range of anthropogenic emissions from a localized industrial complex, has been studied as a model environment for evaluating the spatial gradient of human health risk, which are mainly caused by trace elemental pollutants in soil. Soil elemental profiles in 121 samples from five selected locations representing different degrees of impact from the industrial source were used for human risk estimation. Distance to source dependent cumulative non-carcinogenic hazard indexes above 1 for children (max 4.4 - min 1.5) were found in the study area, ingestion being the most relevant risk pathway. The significance of health risk differences within the study area was confirmed by statistical analysis (ANOVA and HCA) of individual hazard index values at the five sampling locations. As was the dominant factor causing unacceptable carcinogenic risk levels for children (<10(-4)) at the two sampling locations which are closer to the industrial complex, whereas the risk was just in the tolerable range (10(-6) - 10(-4)) for children and adults in the rest of the sampling locations at the study area. Furthermore, we assessed gamma ray radiation external hazard indexes and annual effective dose rate from the natural radioactivity elements ((226)Ra, (232)Th and (40)K) levels in the surface soils of the study area. The highest average values for the specific activity of (232)Th (31 Bq kg(-1)), (40)K (615 Bq kg(- 1)), and (226)Ra (25 Bq kg(-1)) are lower than limit recommended by OECD, so no significant radioactive risk was detected within the study area. In addition, no significant variability of radioactive risk was observed among sampling locations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Arsenic: The Silent Killer

    SciTech Connect

    Foster, Andrea

    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.

  3. Radioactive Decay

    EPA Pesticide Factsheets

    Radioactive decay is the emission of energy in the form of ionizing radiation. Example decay chains illustrate how radioactive atoms can go through many transformations as they become stable and no longer radioactive.

  4. Radioactively Contaminated Sites | RadTown USA | US EPA

    EPA Pesticide Factsheets

    2017-01-17

    If radioactive materials are used or disposed of improperly, they can contaminate buildings and the environment. Every site requiring cleanup is different depending on the type of facility, the radioactive elements involved and the concentration of the radioactive elements.

  5. Study of leachability and fractional alteration of arsenic and co-existing elements in stabilized contaminated sludge using a flow-through extraction system.

    PubMed

    Buanuam, Janya; Wennrich, Rainer

    2011-06-01

    This study investigates the stabilization of As in the contaminated sludge after treatment with MnO(2) or Ca(OH)(2), and the influence of the stabilizing materials on the leachability of the co-existing elements Pb and Zn. By exploiting a continuous-flow assembly facilitating a modified Wenzel's sequential extraction scheme (designed for the fractionation of arsenic), it is possible to ascertain the leachability, mobility and fractional alteration of these elements under stimulated natural (flow-through) leaching conditions. The fractionation data show that more than 80% of As, Pb and Zn in the untreated sludge are bound in the amorphous Fe oxides fraction and residual fraction. The addition of MnO(2) has only an insignificant effect on As fractional transformation, while Ca(OH)(2) caused an increase in As mobility. For Pb, the decrease in leachability was clearly visible. The extractable Pb was reduced by 18% and 40% in stabilized MnO(2) and Ca(OH)(2) sludge samples, respectively. Unlike that of Pb, the mobility of Zn was not affected by the additives used. Their fractional distribution patterns before and after the stabilization process remained the same. The ability to produce detailed leaching profiles for As and other elements (Pb, Zn, Ca, Mn and Fe) meant that elemental associations in individual fractions could be examined. From the MnO(2)-treated sludge, the coincidence of the As, Pb, Zn, Fe, and Mn peaks seems to indicate a close association of these elements in the Fe-oxides-bound fraction. Furthermore, the leaching profiles may be used as evidence of a strong affinity between these elements and added MnO(2).

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

    PubMed

    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.

  7. [Arsenic - Poison or medicine?].

    PubMed

    Kulik-Kupka, Karolina; Koszowska, Aneta; Brończyk-Puzoń, Anna; Nowak, Justyna; Gwizdek, Katarzyna; Zubelewicz-Szkodzińska, Barbara

    2016-01-01

    Arsenic (As) is commonly known as a poison. Only a few people know that As has also been widely used in medicine. In the past years As and its compounds were used as a medicine for the treatment of such diseases as diabetes, psoriasis, syphilis, skin ulcers and joint diseases. Nowadays As is also used especially in the treatment of patients with acute promyelocytic leukemia. The International Agency for Research on Cancer (IARC) has recognized arsenic as an element with carcinogenic effect evidenced by epidemiological studies, but as previously mentioned it is also used in the treatment of neoplastic diseases. This underlines the specificity of the arsenic effects. Arsenic occurs widely in the natural environment, for example, it is present in soil and water, which contributes to its migration to food products. Long exposure to this element may lead to liver damages and also to changes in myocardium. Bearing in mind that such serious health problems can occur, monitoring of the As presence in the environmental media plays a very important role. In addition, the occupational risk of As exposure in the workplace should be identified and checked. Also the standards for As presence in food should be established. This paper presents a review of the 2015 publications based on the Medical database like PubMed and Polish Medical Bibliography. It includes the most important information about arsenic in both forms, poison and medicine. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  8. Mineral resource of the month: arsenic

    USGS Publications Warehouse

    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.

  9. Geochemical processes controlling mobilization of arsenic and trace elements in shallow aquifers and surface waters in the Antequera and Poopó mining regions, Bolivian Altiplano

    NASA Astrophysics Data System (ADS)

    Ramos Ramos, Oswaldo Eduardo; Rötting, Tobias S.; French, Megan; Sracek, Ondra; Bundschuh, Jochen; Quintanilla, Jorge; Bhattacharya, Prosun

    2014-10-01

    A geochemical approach was applied to understand the factors controlling the mobilization of As and trace elements (TEs) in mining areas of the Poopó and Antequera River sub-basins on the Bolivian Altiplano. A total of 52 samples (surface, groundwater and geothermal water) were collected during the rainy season (2009). Arsenic, Cd and Mn concentrations exceed World Health Organization (WHO) drinking water guidelines and Bolivian regulations for drinking water in 28 groundwater samples, but Cu, Ni, Pb and Zn do not. Arsenic, Cd, Mn, Pb and Zn concentrations exceed World Health Organization guidelines for drinking water and Bolivian regulations Class A standard for discharge to water bodies in 20 surface water samples, whereas levels of Cu do not, and Ni and Fe rarely exceed regulation and guideline values. Factor analysis was applied to 18 hydrochemical parameters of 52 samples. Five factors for groundwater (plagioclase weathering, dissolution of gypsum and halite, TEs mobilization at acidic pH, sulfide oxidation, and release of As) account for 86.5% of the total variance for Antequera and 83.9% for Poopó sub-basins. Four factors for surface water data (weathering and mobilization of TEs influenced by pH, dissolution of evaporate salts, neutralization of acid mine drainage, and As release due to dissolution of Mn and Fe oxides) account for 91% of the total variance in Antequera and 96% in Poopó sub-basins. The As and TEs mobilized in these regions could affect the local water sources, which is a prevalent concern with respect to water resource management in this semi-arid Altiplano region. Presence of both natural and anthropogenic sources of contamination requires careful monitoring of water quality.

  10. Arsenic Uptake by Muskmelon (Cucumis melo) Plants from Contaminated Water.

    PubMed

    Hettick, Bryan E; Cañas-Carrell, Jaclyn E; Martin, Kirt; French, Amanda D; Klein, David M

    2016-09-01

    Arsenic is a carcinogenic element that occurs naturally in the environment. High levels of arsenic are found in water in some parts of the world, including Texas. The aims of this study were to determine the distribution of arsenic in muskmelon (Cucumis melo) plants accumulated from arsenic spiked water and to observe effects on plant biomass. Plants were grown and irrigated using water spiked with variable concentrations of arsenic. Inductively coupled plasma mass spectrometry was used to quantify arsenic in different parts of the plant and fruit. Under all conditions tested in this study, the highest concentrations of arsenic were found in the leaves, soil, and roots. Arsenic in the water had no significant effect on plant biomass. Fruits analyzed in this study had arsenic concentrations of 101 μg/kg or less. Consuming these fruits would result in less arsenic exposure than drinking water at recommended levels.

  11. Arsenic poisoning.

    PubMed

    Schoolmeester, W L; White, D R

    1980-02-01

    Arsenic poisoning continues to require awareness of its diverse clinical manifestations. Industry is the major source of arsenic exposure. Although epidemiologic studies strongly contend that arsenic is carcinogenic, there are little supportive research data. Arsenic poisoning, both acute and chronic, is often overlooked initially in the evaluation of the patient with multisystem disease, but once it is suspected, many accurate methods are available to quantitate the amount and duration of exposure. Treatment with dimercaprol remains the mainstay of therapy, and early treatment is necessary to prevent irreversible complications.

  12. Methods of analysis for toxic elements in food products. 2. Review of USSR standards on determinations of heavy metals and arsenic

    SciTech Connect

    Skurikhin, I.M.

    1989-03-01

    Methods of analysis prescribed by USSR standards for Hg, Pb, Zn, As, Cd, Cu, Fe, and Sn in foods are described: for Hg--colorimetry of tetraiodide mercurate and atomic absorption spectroscopy (AAS); for Pb, Cd, Zn, and Cu--polarography; for Cu--colorimetry with sodium diethyldithiocarbamate and zinc dibenzyldithiocarbamate; for As--colorimetry with silver diethyldithiocarbamate; for Sn--colorimetry with quercetin; and for Fe--colorimetry with o-phenanthroline. All of the methods have the necessary metrological characteristics, including intralaboratory repeatability value (r), interlaboratory reproducibility value (R), minimum quantity of the element to be determined in the analytical test portion (MQSM), and the coefficients that account for mercury and arsenic losses during analysis. Establishing constant r- and R-values for the methods under consideration is expedient because (a) the methods suggested are used for safety purposes; and (b) the optimum amount of the element studied in the test sample is determined, to a certain degree, by the mass of the test portion.

  13. Arsenic and other elements in drinking water and dietary components from the middle Gangetic plain of Bihar, India: Health risk index.

    PubMed

    Kumar, Manoj; Rahman, Mohammad Mahmudur; Ramanathan, A L; Naidu, Ravi

    2016-01-01

    This study investigates the level of contamination and health risk assessment for arsenic (As) and other elements in drinking water, vegetables and other food components in two blocks (Mohiuddinagar and Mohanpur) from the Samastipur district, Bihar, India. Groundwater (80%) samples exceeded the World Health Organization (WHO) guideline value (10μg/L) of As while Mn exceeded the previous WHO limit of 400μg/L in 28% samples. The estimated daily intake of As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn from drinking water and food components were 169, 19, 26, 882, 4645, 14582, 474, 1449 and 12,955μg, respectively (estimated exposure 3.70, 0.41, 0.57, 19.61, 103.22, 324.05, 10.53, 32.21 and 287.90μg per kg bw, respectively). Twelve of 15 cooked rice contained high As concentration compared to uncooked rice. Water contributes (67%) considerable As to daily exposure followed by rice and vegetables. Whereas food is the major contributor of other elements to the dietary exposure. Correlation and principal component analysis (PCA) indicated natural source for As but for other elements, presence of diffused anthropogenic activities were responsible. The chronic daily intake (CDI) and health risk index (HRI) were also estimated from the generated data. The HRI were >1 for As in drinking water, vegetables and rice, for Mn in drinking water, vegetables, rice and wheat, for Pb in rice and wheat indicated the potential health risk to the local population. An assessment of As and other elements of other food components should be conducted to understand the actual health hazards caused by ingestion of food in people residing in the middle Gangetic plain. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Geogenic arsenic and other trace elements in the shallow hydrogeologic system of Southern Poopó Basin, Bolivian Altiplano.

    PubMed

    Ormachea Muñoz, Mauricio; Wern, Hannes; Johnsson, Fredrick; Bhattacharya, Prosun; Sracek, Ondra; Thunvik, Roger; Quintanilla, Jorge; Bundschuh, Jochen

    2013-11-15

    Environmental settings in the southern area of Lake Poopó in the Bolivian highlands, the Altiplano, have generated elevated amounts of arsenic (As) in the water. The area is characterised by a semiarid climate, slow hydrological flow and geologic formations of predominantly volcanic origin. The present study aimed at mapping the extent of the water contamination in the area and to investigate the geogenic sources and processes involved in the release of As to the groundwater. Ground- and surface-water samples were collected from 24 different sites, including drinking water wells and rivers, in the southern Poopó basin in two different field campaigns during the dry and rainy seasons. The results revealed variable levels of As in shallow drinking water wells and average concentration exceeding the WHO guidelines value. Arsenic concentrations range from below 5.2 μg/L (the detection level) to 207 μg/L and averages 72 μg/L. Additionally, high boron (B) concentrations (average 1902 μg/L), and high salinity are further serious concerns for deteriorating the groundwater quality and rendering it unsuitable for drinking. Groundwater is predominantly of the Na-Cl-HCO3 type or the Ca-Na-HCO3 type with neutral or slightly alkaline pH and oxidising character. While farmers are seriously concerned about the water scarcity, and on a few occasions about salinity, there are no concerns about As and B present at levels exceeding the WHO guidelines, and causing negative long term effects on human health. Sediment samples from two soil profiles and a river bed along with fourteen rock samples were also collected and analysed. Sequential extractions of the sediments together with the calculation of the mineral saturation indices indicate that iron oxides and hydroxides are the important secondary minerals phases which are important adsorbents for As. High pH values, and the competition of As with HCO3 and dissolved silica for the adsorption sites probably seems to be an

  15. Arsenic, Anaerobes, and Astrobiology

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

  16. A Phytoremediation Strategy for Arsenic

    SciTech Connect

    Meagher, Richard B.

    2005-06-01

    . Phytochelatins bind diverse thiol-reactive elements like As(III) and are synthesized from amino acids in a three-step enzymatic pathway utilizing three enzymes: ECS = gamma-glutamylcysteine synthetase; GS = GSH synthetase; and PS = phytochelatin synthase. We cloned each of the genes that encode these enzymes and used at least two different plant promoters to express them in transgenic Arabidopsis. We have shown that all three confer significant resistance to arsenic and allow rapid growth on a concentration of arsenic (300 micromolar) that kills wild-type seeds and plants.

  17. Radioactive mineral springs in Delta County, Colorado

    USGS Publications Warehouse

    Cadigan, Robert A.; Rosholt, John N.; Felmlee, J. Karen

    1976-01-01

    The system of springs in Delta County, Colo., contains geochemical clues to the nature and location of buried uranium-mineralized rock. The springs, which occur along the Gunnison River and a principal tributary between Delta and Paonia, are regarded as evidence of a still-functioning hydrothermal system. Associated with the springs are hydrogen sulfide and sulfur dioxide gas seeps, carbon dioxide gas-powered geysers, thick travertine deposits including radioactive travertine, and a flowing warm-water (41?C) radioactive well. Geochemical study of the springs is based on surface observations, on-site water-property measurements, and sampling of water, travertine, soft precipitates, and mud. The spring deposits are mostly carbonates, sulfates, sulfides, and chlorides that locally contain notable amounts of some elements, such as arsenic, barium, lithium, and radium. Samples from five localities have somewhat different trace element assemblages even though they are related to the same hydrothermal system. All the spring waters but one are dominated by sodium chloride or sodium bicarbonate. The exception is an acid sulfate water with a pH of 2.9, which contains high concentrations of aluminum and iron. Most of the detectable radioactivity is due to the presence of radium-226, a uranium daughter product, but at least one spring precipitate contains abundant radium-228, a thorium daughter product. The 5:1 ratio of radium-228 to radium-226 suggests the proximity of a vein-type deposit as a source for the radium. The proposed locus of a thorium-uranium mineral deposit is believed to lie in the vicinity of Paonia, Colo. Exact direction and depth are not determinable from data now available.

  18. Concentrations of Ni and V, other heavy metals, arsenic, elemental and organic carbon in atmospheric fine particles (PM2.5) from Puerto Rico

    PubMed Central

    Figueroa, David Acevedo; Rodríguez-Sierra, Carlos J; Jiménez-Velez, Braulio D

    2015-01-01

    Fine atmospheric particulate PM2.5 (particles with diameters of <2.5 μm) were sampled in an urban industrialized area – Guaynabo, Puerto Rico (Figure 1) – and in a reference less polluted site – Fajardo, Puerto Rico – and analyzed for trace metals, and inorganic and organic elemental carbon. PM2.5 samples were collected from November 2000 to September 2001 using an Andersen Instruments RAAS2.5-400 for periods of 72 h. Metals analyzed were arsenic (As), cadmium (Cd), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), vanadium (V) and zinc (Zn) by atomic absorption. Levels of elemental and organic carbon (EC/OC) were also determined. All metals analyzed, except for Fe, were significantly higher in PM2.5 from Guaynabo when compared to Fajardo. Average levels of PM2.5 in Guaynabo were 11.6 versus 8.5 μg/m3 in Fajardo. Average levels of EC were 1.5 and <0.14 μg/m3; and OC levels were 2.2 and <1 μg/m3 for Guaynabo and Fajardo, respectively. Levels of Ni (17 ng/m3) and V (40 ng/m3) determined in PM2.5 from the Guaynabo area were high when compared to other cities, and these metals could be responsible for respiratory problems reported in the area. Multivariate analyses showed strong relationships in Guaynabo between Ni and V, PM2.5 and Fe and As and Cu and Pb. In Fajardo, the strongest associations were obtained between PM2.5 and Fe, Cd and V and Ni and Pb and Cu, these last three elements exhibiting an inverse relationship. PMID:16716038

  19. Mobilization of arsenic and other trace elements of health concern in groundwater from the Salí River Basin, Tucumán Province, Argentina.

    PubMed

    Nicolli, Hugo B; García, Jorge W; Falcón, Carlos M; Smedley, Pauline L

    2012-04-01

    The Salí River Basin in north-west Argentina (7,000 km(2)) is composed of a sequence of Tertiary and Quaternary loess deposits, which have been substantially reworked by fluvial and aeolian processes. As with other areas of the Chaco-Pampean Plain, groundwater in the basin suffers a range of chemical quality problems, including arsenic (concentrations in the range of 12.2-1,660 μg L(-1)), fluoride (50-8,740 μg L(-1)), boron (34.0-9,550 μg L(-1)), vanadium (30.7-300 μg L(-1)) and uranium (0.03-125 μg L(-1)). Shallow groundwater (depths up to 15 m) has particularly high concentrations of these elements. Exceedances above WHO (2011) guideline values are 100% for As, 35% for B, 21% for U and 17% for F. Concentrations in deep (>200 m) and artesian groundwater in the basin are also often high, though less extreme than at shallow depths. The waters are oxidizing, with often high bicarbonate concentrations (50.0-1,260 mg L(-1)) and pH (6.28-9.24). The ultimate sources of these trace elements are the volcanic components of the loess deposits, although sorption reactions involving secondary Al and Fe oxides also regulate the distribution and mobility of trace elements in the aquifers. In addition, concentrations of chromium lie in range of 79.4-232 μg L(-1) in shallow groundwater, 129-250 μg L(-1) in deep groundwater and 110-218 μg L(-1) in artesian groundwater. All exceed the WHO guideline value of 50 μg L(-1). Their origin is likely to be predominantly geogenic, present as chromate in the ambient oxic and alkaline aquifer conditions.

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

    SciTech Connect

    Kitchin, Kirk T. Wallace, Kathleen

    2008-10-15

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

  1. Clean process to destroy arsenic-containing organic compounds with recovery of arsenic

    DOEpatents

    Upadhye, Ravindra S.; Wang, Francis T.

    1996-01-01

    A reduction method is provided for the treatment of arsenic-containing organic compounds with simultaneous recovery of pure arsenic. Arsenic-containing organic compounds include pesticides, herbicides, and chemical warfare agents such as Lewisite. The arsenic-containing compound is decomposed using a reducing agent. Arsine gas may be formed directly by using a hydrogen-rich reducing agent, or a metal arsenide may be formed using a pure metal reducing agent. In the latter case, the arsenide is reacted with an acid to form arsine gas. In either case, the arsine gas is then reduced to elemental arsenic.

  2. Clean process to destroy arsenic-containing organic compounds with recovery of arsenic

    DOEpatents

    Upadhye, R.S.; Wang, F.T.

    1996-08-13

    A reduction method is provided for the treatment of arsenic-containing organic compounds with simultaneous recovery of pure arsenic. Arsenic-containing organic compounds include pesticides, herbicides, and chemical warfare agents such as Lewisite. The arsenic-containing compound is decomposed using a reducing agent. Arsine gas may be formed directly by using a hydrogen-rich reducing agent, or a metal arsenide may be formed using a pure metal reducing agent. In the latter case, the arsenide is reacted with an acid to form arsine gas. In either case, the arsine gas is then reduced to elemental arsenic. 1 fig.

  3. Impact of sedimentary provenance and weathering on arsenic distribution in aquifers of the Datong basin, China: Constraints from elemental geochemistry

    NASA Astrophysics Data System (ADS)

    Xie, Xianjun; Wang, Yanxin; Ellis, Andre; Liu, Chongxuan; Duan, Mengyu; Li, Junxia

    2014-11-01

    Arsenic (As)-contaminated aquifer sediments from Datong basin, China have been analyzed to infer the provenance and depositional environment related to As distribution in the aquifer sediments. The As content in the sediments ranged from 2.45 to 27.38 mg/kg with an average value of 9.54 mg/kg, which is comparable to the average value in modern unconsolidated sediments. However, minor variation in As concentration with depth has been observed in the core. There was a significant correlation between Fe, and Al and As, which was attributed to the adsorption or co-precipitation of As onto/with Fe oxides/hydroxides and/or Fe-coated clay minerals. Post-Archean Australian Shale (PAAS)-normalized REEs patterns of sediment samples along the borehole were constant, and the sediments had a notably restricted range of LaN/YbN ratios from 0.7 to 1.0. These results suggested that the provenance of the Datong basin remained similar throughout the whole depositional period. The analysis of major geochemical compositions confirmed that all core sediments were from the same sedimentary source and experienced significant sedimentary recycling. The co-variation of As, V/Al, Ni/Al and chemical index of alteration (CIA) values in the sediments along the borehole suggested that As distribution in the sediments was primarily controlled by weathering processes. The calculated CIA values of the sediments along the borehole indicate that a relative strong chemical weathering occurred during the deposition of sediments at depths of ∼35 to 88 m, which was corresponding to the depth at which high As groundwater was observed at the site. Strong chemical weathering favored the deposition of Fe-bearing minerals including poorly crystalline and crystalline Fe oxide mineral phases and concomitant co-precipitation of As with these minerals in the sediments. Subsequent reductive dissolution of As-bearing poorly crystalline and crystalline Fe oxides would result in the enrichment of As in groundwater

  4. Impact of sedimentary provenance and weathering on arsenic distribution in aquifers of the Datong basin, China: Constraints from elemental geochemistry

    SciTech Connect

    Xie, Xianjun; Wang, Yanxin; Ellis, Andre; Liu, Chongxuan; Duan, Mengyu; Li, Junxia

    2014-11-01

    Arsenic (As)-contaminated aquifer sediments from Datong basin, China have been analyzed to infer the provenance and depositional environment related to As distribution in the aquifer sediments. The As content in the sediments ranged from 2.45 to 27.38 mg/kg with an average value of 9.54 mg/kg, which is comparable to the average value in modern unconsolidated sediments. However, minor variation in As concentration with depth has been observed in the core. There was a significant correlation between Fe, and Al and As, which was attributed to the adsorption or co-precipitation of As onto/with Fe oxides/hydroxides and/or Fe-coated clay minerals. Post-Archean Australian Shale (PAAS)-normalized REEs patterns of sediment samples along the borehole were constant, and the sediments had a notably restricted range of La-N/Yb-N ratios from 0.7 to 1.0. These results suggested that the provenance of the Datong basin remained similar throughout the whole depositional period. The analysis of major geochemical compositions confirmed that all core sediments were from the same sedimentary source and experienced significant sedimentary recycling. The co-variation of As, V/Al, Ni/Al and chemical index of alteration (CIA) values in the sediments along the borehole suggested that As distribution in the sediments was primarily controlled by weathering processes. The calculated CIA values of the sediments along the borehole indicate that a relative strong chemical weathering occurred during the deposition of sediments at depths of similar to 35 to 88 m, which was corresponding to the depth at which high As groundwater was observed at the site. Strong chemical weathering favored the deposition of Fe-bearing minerals including poorly crystalline and crystalline Fe oxide mineral phases and concomitant co-precipitation of As with these minerals in the sediments. Subsequent reductive dissolution of As-bearing poorly crystalline and crystalline Fe oxides would result in the enrichment of As in

  5. Distribution of arsenic, selenium, and other trace elements in high pyrite Appalachian coals: evidence for multiple episodes of pyrite formation

    USGS Publications Warehouse

    Diehl, S.F.; Goldhaber, M.B.; Koenig, A.E.; Lowers, H.A.; Ruppert, L.F.

    2012-01-01

    Pennsylvanian coals in the Appalachian Basin host pyrite that is locally enriched in potentially toxic trace elements such as As, Se, Hg, Pb, and Ni. A comparison of pyrite-rich coals from northwestern Alabama, eastern Kentucky, and West Virginia reveals differences in concentrations and mode of occurrence of trace elements in pyrite. Pyrite occurs as framboids, dendrites, or in massive crystalline form in cell lumens or crosscutting veins. Metal concentrations in pyrite vary over all scales, from microscopic to mine to regional, because trace elements are inhomogeneously distributed in the different morphological forms of pyrite, and in the multiple generations of sulfide mineral precipitates. Early diagenetic framboidal pyrite is usually depleted in As, Se, and Hg, and enriched in Pb and Ni, compared to other pyrite forms. In dendritic pyrite, maps of As distribution show a chemical gradient from As-rich centers to As-poor distal branches, whereas Se concentrations are highest at the distal edges of the branches. Massive crystalline pyrite that fills veins is composed of several generations of sulfide minerals. Pyrite in late-stage veins commonly exhibits As-rich growth zones, indicating a probable epigenetic hydrothermal origin. Selenium is concentrated at the distal edges of veins. A positive correlation of As and Se in pyrite veins from Kentucky coals, and of As and Hg in pyrite-filled veins from Alabama coals, suggests coprecipitation of these elements from the same fluid. In the Kentucky coal samples (n = 18), As and Se contents in pyrite-filled veins average 4200 ppm and 200 ppm, respectively. In Alabama coal samples, As in pyrite-filled veins averages 2700 ppm (n = 34), whereas As in pyrite-filled cellular structures averages 6470 ppm (n = 35). In these same Alabama samples, Se averages 80 ppm in pyrite-filled veins, but was below the detection limit in cell structures. In samples of West Virginia massive pyrite, As averages 1700 ppm, and Se averages 270

  6. NATURAL RADIOACTIVITY LEVEL AND ELEMENTAL COMPOSITION OF SOIL SAMPLES FROM A HIGH BACKGROUND RADIATION AREA ON EASTERN COAST OF INDIA (ODISHA).

    PubMed

    Sahoo, S K; Kierepko, R; Sorimachi, A; Omori, Y; Ishikawa, T; Tokonami, S; Prasad, G; Gusain, G S; Ramola, R C

    2016-10-01

    A comprehensive study was carried out to determine the radioactivity concentration of soil samples from different sites of a high background radiation area in the eastern coast of India, Odisha state. The dose rate measured in situ varied from 0.25 to 1.2 µSv h(-1) The gamma spectrometry measurements indicated Th series elements as the main contributors to the enhanced level of radiation and allowed the authors to find the mean level of the activity concentration (±SD) for (226)Ra, (228)Th and (40)K as 130±97, 1110±890 and 360±140 Bq kg(-1), respectively. Human exposure from radionuclides occurring outdoor was estimated based on the effective dose rate, which ranged from 0.14±0.02 to 2.15±0.26 mSv and was higher than the UNSCEAR annual worldwide average value 0.07 mSv. Additionally, X-ray fluorescence analysis provided information about the content of major elements in samples and indicated the significant amount of Ti (7.4±4.9 %) in soils.

  7. Arsenic and associated trace-elements in groundwater from the Chaco-Pampean plain, Argentina: results from 100 years of research.

    PubMed

    Nicolli, Hugo B; Bundschuh, Jochen; Blanco, María Del C; Tujchneider, Ofelia C; Panarello, Héctor O; Dapeña, Cristina; Rusansky, Jorge E

    2012-07-01

    The Chaco-Pampean plain, Argentina, is a vast geographical unit (1,000,000 km²) affected by high arsenic (As) concentrations in universal oxidizing groundwater. The socio-economic development of the region is restricted by water availability and its low quality caused by high salinity and hardness. In addition, high As and associated trace-elements (F, U, V, B, Se, Sb, Mo) concentrations of geogenic origin turn waters unsuitable for human consumption. Shallow groundwater with high As and F concentrations (ranges: <10-5300 μg As/L; 51-7,340 μg F/L) exceeding the WHO guideline values (As: 10 μg/L; F: 1,500 μg/L) introduces a potential risk of hydroarsenicism disease in the entire region and fluorosis in some areas. The rural population is affected (2-8 million inhabitants). Calcareous loess-type sediments and/or intercalated volcanic ash layers in pedosedimentary sequences hosting the aquifers are the sources of contaminant trace-elements. Large intra and interbasin variabilities of trace-element concentrations, especially between shallow and deep aquifers have been observed. All areas of the Chaco-Pampean plain were affected in different grades: the Chaco-Salteña plain (in the NNE of the region) and the northern La Pampa plain (in the center-south) have been shown the highest concentrations. The ranges of As and F contents in loess-sediments are 6-25 and 534-3340 mg/kg, respectively in the Salí River basin. Three key processes render high As concentrations in shallow aquifers: i) volcanic glass dissolution and/or hydrolysis and leaching of silicates minerals hosted in loess; ii) desorption processes from the surface of Al-, Fe- and Mn-oxi-hydroxides (coating lithic fragments) at high pH and mobilization as complex oxyanions (As and trace elements)in Na-bicarbonate type groundwaters; and iii) evaporative concentration in areas with semiarid and arid climates. Local factors play also an important role in the control of high As concentrations, highly influenced

  8. Determination of radioactive elements and heavy metals in sediments and soil from domestic water sources in northern peninsular Malaysia.

    PubMed

    Muhammad, Bashir G; Jaafar, Mohammad Suhaimi; Abdul Rahman, Azhar; Ingawa, Farouk Abdulrasheed

    2012-08-01

    Soil serves as a major reservoir for contaminants as it posseses an ability to bind various chemicals together. To safeguard the members of the public from an unwanted exposure, studies were conducted on the sediments and soil from water bodies that form the major sources of domestic water supply in northern peninsular Malaysia for their trace element concentration levels. Neutron Activation Analysis, using Nigeria Research Reactor-1 (NIRR-1) located at the Centre for Energy Research and Training, Zaria, Nigeria was employed as the analytical tool. The elements identified in major quantities include Na, K, and Fe while As, Br, Cr, U, Th, Eu, Cs, Co, La, Sm, Yb, Sc, Zn, Rb, Ba, Lu, Hf, Ta, and Sb were also identified in trace quantities. Gamma spectroscopy was also employed to analyze some soil samples from the same area. The results indicated safe levels in terms of the radium equivalent activity, external hazard index as well as the mean external exposure dose rates from the soil. The overall screening of the domestic water sources with relatively high heavy metals concentration values in sediments and high activity concentration values in soil is strongly recommended as their accumulation overtime as a consequence of leaching into the water may be of health concern to the members of the public.

  9. REDOX state analysis of platinoid elements in simulated high-level radioactive waste glass by synchrotron radiation based EXAFS

    NASA Astrophysics Data System (ADS)

    Okamoto, Yoshihiro; Shiwaku, Hideaki; Nakada, Masami; Komamine, Satoshi; Ochi, Eiji; Akabori, Mitsuo

    2016-04-01

    Extended X-ray Absorption Fine Structure (EXAFS) analyses were performed to evaluate REDOX (REDuction and OXidation) state of platinoid elements in simulated high-level nuclear waste glass samples prepared under different conditions of temperature and atmosphere. At first, EXAFS functions were compared with those of standard materials such as RuO2. Then structural parameters were obtained from a curve fitting analysis. In addition, a fitting analysis used a linear combination of the two standard EXAFS functions of a given elements metal and oxide was applied to determine ratio of metal/oxide in the simulated glass. The redox state of Ru was successfully evaluated from the linear combination fitting results of EXAFS functions. The ratio of metal increased at more reducing atmosphere and at higher temperatures. Chemical form of rhodium oxide in the simulated glass samples was RhO2 unlike expected Rh2O3. It can be estimated rhodium behaves according with ruthenium when the chemical form is oxide.

  10. Mineral resource of the month: Arsenic

    USGS Publications Warehouse

    Bedinger, George M.

    2014-01-01

    Arsenic is a gray metal rarely encountered as a free element, but is widely distributed in minerals and ores that contain copper, iron and lead. Arsenic is often found in groundwater as a result of the natural weathering of rock and soil.

  11. Blood arsenic: Pan-India prevalence.

    PubMed

    Iyer, Sandhya; Sengupta, Caesar; Velumani, A

    2016-04-01

    Arsenic, a well-known toxic element, has become one of the biggest causes for clinical concerns among elemental toxicities. Arsenicosis has been reported from many regions of the country, especially on exposure induced by ground water contamination. The clinical effects of chronic arsenic toxicity are generally varied and its timely diagnosis and management pose a big challenge. Our study reports analysis of blood arsenic levels in a pan-India cohort of 205,530 including 111,737 males and 93,793 females respectively. The cohort included all age groups from infants to old adults. Arsenic levels were analyzed using the analytical platform of ICP-MS touted to be the gold standard for elemental analysis. Blood arsenic levels of ≥5 μg/L were considered high in our study. The total frequency of high arsenic cases detected in the study is 1.37%. The frequency in males was 1.47% and in females it was detected to be 1.25%. Also, maximum cases of high arsenic levels were detected to be from the state of Kerala and in cities from Mumbai. Very few studies have recorded the frequency of high arsenic levels in Indians as well as its average blood levels in a pan-India cohort. Our study has made a pilot attempt to highlight the same to generate awareness about this elemental menace in the Indian context. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Industrial contributions of arsenic to the environment.

    PubMed Central

    Nelson, K W

    1977-01-01

    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. PMID:908308

  13. Health Effects of Chronic Arsenic Exposure

    PubMed Central

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

    2014-01-01

    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. PMID:25284195

  14. Geomicrobial interactions with arsenic and antimony

    USGS Publications Warehouse

    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.

  15. Arsenic in stream sediments of northern Alabama

    USGS Publications Warehouse

    Goldhaber, M.B.; Irwin, Elise; Atkins, Brian; Lee, Lopaka; Black, D.D.; Zappia, Humbert; Hatch, Joe; Pashin, Jack; Barwick, L.H.; Cartwright, W.E.; Sanzolone, Rick; Rupert, Leslie; Kolker, Allan; Finkelman, Robert

    2001-01-01

    OVERVIEW OF ARSENIC IN STREAM SEDIMENTS The overall range of arsenic in the NURE stream sediments was from 0.3 to 44 mg/kg sediment (ppm) As in the sample data set. The mean value was 4.3 ppm with a standard deviation of 4.1 ppm. For comparison, the crustal abundance of arsenic is 1.8 ppm (Taylor, 1964). Shale is higher, with average values of 15 ppm. Coal samples from the entire USGS National Coal Resource Data System coal database (Finkelman, 1994) average 24 ppm arsenic. A study of stream sediments from throughout the U.S. by the USGS NAWQA program reported that the 75th percentile for arsenic in 541 stream sediments was 9.5 ppm (Rice, 1999). Given the relatively low crustal abundance of arsenic, a number of stream-sediment samples in this study may be considered geochemically anomalous in this element.

  16. Toxicity of arsenic (III) and (V) on plant growth, element uptake, and total amylolytic activity of mesquite (Prosopis juliflora x P. velutina).

    PubMed

    Mokgalaka-Matlala, Ntebogeng S; Flores-Tavizón, Edith; Castillo-Michel, Hiram; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

    2008-01-01

    The effects of arsenite [As(III)] and arsenate [As(V)] on the growth of roots, stems, and leaves and the uptake of arsenic (As), micro- and macronutrients, and total amylolytic activity were investigated to elucidate the phytotoxicity of As to the mesquite plant (Prosopis juliflora x P. velutina). The plant growth was evaluated by measuring the root and shoot length, and the element uptake was determined using inductively coupled plasma optical emission spectroscopy. The root and leaf elongation decreased significantly with increasing As(III) and As(V) concentrations; whereas, stem elongation remained unchanged. The As uptake increased with increasing As(III) or As(V) concentrations in the medium. Plants treated with 50 mg/L As(III) accumulated up to 920 mg/kg dry weight (d wt) in roots and 522 mg/kg d wt in leaves, while plants exposed to 50 mg/L As(V) accumulated 1980 and 210 mg/kg d wt in roots and leaves, respectively. Increasing the As(V) concentration up to 20 mg/L resulted in a decrease in the total amylolytic activity. On the contrary, total amylolytic activity in As(III)-treated plants increased with increasing As concentration up to 20 mg/L. The macro- and micronutrient concentrations changed in As-treated plants. In shoots, Mo and K were reduced but Ca was increased, while in roots Fe and Ca were increased but K was reduced. These changes reduced the size of the plants, mainly in the As(III)-treated plants; however, there were no visible sign of As toxicity.

  17. Study on emission of hazardous trace elements in a 350 MW coal-fired power plant. Part 2. arsenic, chromium, barium, manganese, lead.

    PubMed

    Zhao, Shilin; Duan, Yufeng; Chen, Lei; Li, Yaning; Yao, Ting; Liu, Shuai; Liu, Meng; Lu, Jianhong

    2017-07-01

    Hazardous Trace elements (HTEs) emitted from coal combustion has raised widespread concern. Studies on the emission characteristics of five HTEs, namely arsenic (As), chromium (Cr), barium (Ba), manganese (Mn), lead (Pb) at three different loads (100%, 83%, 71% output) and different coal types were performed on a 350 MW coal-fired power plant equipped with SCR, ESP + FF, and WFGD. HTEs in the flue gas at the inlet/outlet of each air pollution control device (APCD) were sampled simultaneously based on US EPA Method 29. During flue gas HTEs sampling, coal, bottom ash, fly ash captured by ESP + FF, fresh desulfurization slurry, desulfurization wastewater were also collected. Results show that mass balance rate for the system and each APCD is in an acceptable range. The five studied HTEs mainly distribute in bottom and ESP + FF ash. ESP + FF have high removal efficiency of 99.75-99.95%. WFGD can remove part of HTEs further. Total removal rate across the APCDs ranges from 99.84 to 99.99%. Concentration of HTEs emitted to atmosphere is within the extremely low scope of 0.11-4.93 μg/m(3). Emission factor of the five studied HTEs is 0.04-1.54 g/10(12)J. Content of As, Pb, Ba, Cr in solid samples follows the order of ESP + FF ash > bottom ash > gypsum. More focus should be placed on Mn in desulfuration wastewater, content of which is more than the standard value. This work is meaningful for the prediction and removal of HTEs emitted from coal-fired power plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Metabolic interrelationships between arsenic and selenium

    PubMed Central

    Levander, Orville A.

    1977-01-01

    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

  19. Arsenic chemistry in soils and sediments

    SciTech Connect

    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 dissolved

  20. Long-term monitoring of arsenic, copper, selenium, and other elements in Great Salt Lake (Utah, USA) surface water, brine shrimp, and brine flies.

    PubMed

    Adams, William J; DeForest, David K; Tear, Lucinda M; Payne, Kelly; Brix, Kevin V

    2015-03-01

    This paper presents long-term monitoring data for 19 elements with a focus on arsenic (As), copper (Cu), and selenium (Se), in surface water (2002-2011), brine shrimp (2001-2011), and brine flies (1995-1996) collected from Great Salt Lake (GSL, Utah, USA). In open surface waters, mean (±standard deviation [SD]; range; n) As concentrations were 112 (±22.1; 54.0-169; 47) and 112 μg/L (±35.6; 5.1-175; 68) in filtered and unfiltered surface water samples, respectively, and 16.3 μg/g (±5.6; 5.1-35.2; 62) dry weight (dw) in brine shrimp. Mean (±SD; range; n) Cu concentrations were 4.2 (±2.1; 1.3-12.5; 47) and 6.9 μg/L (±6.6; 1.9-38.1; 68) in filtered and unfiltered surface water samples, respectively, and 20.6 μg/g (±18.4; 5.4-126; 62) dw in brine shrimp. Finally, mean (±SD; range; n) dissolved and total recoverable Se concentrations were 0.6 (±0.1; 0.4-1.2; 61) and 0.9 μg/L (±0.7; 0.5-3.6; 89), respectively, and 3.6 μg/g (±2.2; 1.1-14.9; 98) dw in brine shrimp. Thus, Se in open lake surface waters was most often in the range of 0.5-1 μg/L, and concentrations in both surface water and brine shrimp were comparable to concentrations measured in other monitoring programs for the GSL. Temporally, the statistical significance of differences in mean dissolved or total recoverable As, Cu, and Se concentrations between years was highly variable depending which test statistic was used, and there was no clear evidence of increasing or decreasing trends. In brine shrimp, significant differences in annual mean concentrations of As, Cu, and Se were observed using both parametric and nonparametric statistical approaches, but, as for water, there did not appear to be a consistent increase or decrease in concentrations of these elements over time.

  1. Radioactive ion detector

    DOEpatents

    Bower, Kenneth E.; Weeks, Donald R.

    1997-01-01

    Apparatus for detecting the presence, in aqueous media, of substances which emit alpha and/or beta radiation and determining the oxidation state of these radioactive substances, that is, whether they are in cationic or anionic form. In one embodiment, a sensor assembly has two elements, one comprised of an ion-exchange material which binds cations and the other comprised of an ion-exchange material which binds anions. Each ion-exchange element is further comprised of a scintillation plastic and a photocurrent generator. When a radioactive substance to which the sensor is exposed binds to either element and emits alpha or beta particles, photons produced in the scintillation plastic illuminate the photocurrent generator of that element. Sensing apparatus senses generator output and thereby indicates whether cationic species or anionic species or both are present and also provides an indication of species quantity.

  2. Radioactive ion detector

    DOEpatents

    Bower, K.E.; Weeks, D.R.

    1997-08-12

    Apparatus for detecting the presence, in aqueous media, of substances which emit alpha and/or beta radiation and determining the oxidation state of these radioactive substances, that is, whether they are in cationic or anionic form. In one embodiment, a sensor assembly has two elements, one comprised of an ion-exchange material which binds cations and the other comprised of an ion-exchange material which binds anions. Each ion-exchange element is further comprised of a scintillation plastic and a photocurrent generator. When a radioactive substance to which the sensor is exposed binds to either element and emits alpha or beta particles, photons produced in the scintillation plastic illuminate the photocurrent generator of that element. Sensing apparatus senses generator output and thereby indicates whether cationic species or anionic species or both are present and also provides an indication of species quantity. 2 figs.

  3. Arsenic: Not So Evil After All?

    NASA Astrophysics Data System (ADS)

    Lykknes, Annette; Kvittingen, Lise

    2003-05-01

    This article presents parts of the history of the element arsenic in order to illustrate processes behind development of knowledge in chemistry. The particular aspects presented here are the use of arsenic as a stimulant by Styrian peasants, in Fowler's solution, in drugs of the 19th century (e.g., salvarsan), and in current medical treatment, all of which challenge the myth of this element as exclusively poisonous.

  4. Arsenic speciation and sorption in natural environments

    USGS Publications Warehouse

    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.

  5. Trace Elements and Health

    ERIC Educational Resources Information Center

    Pettyjohn, Wayne A.

    1972-01-01

    Summarizes the effects of arsenic, lead, zinc, mercury, and cadmium on human health, indicates the sources of the elements in water, and considers the possibility of students in high schools analyzing water for trace amounts of the elements. (AL)

  6. Trace Elements and Health

    ERIC Educational Resources Information Center

    Pettyjohn, Wayne A.

    1972-01-01

    Summarizes the effects of arsenic, lead, zinc, mercury, and cadmium on human health, indicates the sources of the elements in water, and considers the possibility of students in high schools analyzing water for trace amounts of the elements. (AL)

  7. Arsenic levels in immigrant children from countries at risk of consuming arsenic polluted water compared to children from Barcelona.

    PubMed

    Piñol, S; Sala, A; Guzman, C; Marcos, S; Joya, X; Puig, C; Velasco, M; Velez, D; Vall, O; Garcia-Algar, O

    2015-11-01

    Arsenic is a highly toxic element that pollutes groundwater, being a major environmental problem worldwide, especially in the Bengal Basin. About 40% of patients in our outpatient clinics come from those countries, and there is no published data about their arsenic exposure. This study compares arsenic exposure between immigrant and native children. A total of 114 children (57 natives, 57 immigrants), aged 2 months to 16 years, were recruited and sociodemographic and environmental exposure data were recorded. Total arsenic in urine, hair, and nails and arsenic-speciated compounds in urine were determined. We did not find significant differences in total and inorganic arsenic levels in urine and hair, but in organic arsenic monomethylarsenic acid (MMA) and dimethylarsinous acid (DMA) in urine and in total arsenic in nails. However, these values were not in the toxic range. There were significant differences between longer than 5 years exposure and less than 5 years exposure (consumption of water from tube wells), with respect to inorganic and organic MMA arsenic in urine and total arsenic in nails. There was partial correlation between the duration of exposure and inorganic arsenic levels in urine. Immigrant children have higher arsenic levels than native children, but they are not toxic. At present, there is no need for specific arsenic screening or follow-up in immigrant children recently arrived in Spain from exposure high-risk countries.

  8. Radioactive Wastes.

    PubMed

    Choudri, B S; Baawain, Mahad

    2016-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2015. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes.

  9. Radioactive Wastes.

    PubMed

    Choudri, B S; Baawain, Mahad

    2015-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2014. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes.

  10. Radioactive Wastes.

    PubMed

    Choudri, B S; Charabi, Yassine; Baawain, Mahad; Ahmed, Mushtaque

    2017-10-01

    Papers reviewed herein present a general overview of radioactive waste related activities around the world in 2016. The current reveiw include studies related to safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation. Further, the review highlights on management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in ecosystem, water and soil alongwith other progress made in the management of radioactive wastes.

  11. Radioactive Wastes.

    PubMed

    Choudri, B S; Baawain, Mahad

    2016-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2015. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes.

  12. Arsenic: toxicity, oxidative stress and human disease.

    PubMed

    Jomova, K; Jenisova, Z; Feszterova, M; Baros, S; Liska, J; Hudecova, D; Rhodes, C J; Valko, M

    2011-03-01

    Arsenic (As) is a toxic metalloid element that is present in air, water and soil. Inorganic arsenic tends to be more toxic than organic arsenic. Examples of methylated organic arsenicals include monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)]. Reactive oxygen species (ROS)-mediated oxidative damage is a common denominator in arsenic pathogenesis. In addition, arsenic induces morphological changes in the integrity of mitochondria. Cascade mechanisms of free radical formation derived from the superoxide radical, combined with glutathione-depleting agents, increase the sensitivity of cells to arsenic toxicity. When both humans and animals are exposed to arsenic, they experience an increased formation of ROS/RNS, including peroxyl radicals (ROO•), the superoxide radical, singlet oxygen, hydroxyl radical (OH•) via the Fenton reaction, hydrogen peroxide, the dimethylarsenic radical, the dimethylarsenic peroxyl radical and/or oxidant-induced DNA damage. Arsenic induces the formation of oxidized lipids which in turn generate several bioactive molecules (ROS, peroxides and isoprostanes), of which aldehydes [malondialdehyde (MDA) and 4-hydroxy-nonenal (HNE)] are the major end products. This review discusses aspects of chronic and acute exposures of arsenic in the etiology of cancer, cardiovascular disease (hypertension and atherosclerosis), neurological disorders, gastrointestinal disturbances, liver disease and renal disease, reproductive health effects, dermal changes and other health disorders. The role of antioxidant defence systems against arsenic toxicity is also discussed. Consideration is given to the role of vitamin C (ascorbic acid), vitamin E (α-tocopherol), curcumin, glutathione and antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase in their protective roles against arsenic-induced oxidative stress. Copyright © 2011 John Wiley & Sons, Ltd.

  13. Arsenic. Can this toxic metalloid sustain life?

    PubMed

    Wilcox, Dean E

    2013-01-01

    It was recently reported that a bacterium, Halomonas species GFAJ-1, isolated from arsenic-rich Mono Lake and further selected for growth under conditions of high arsenate and low phosphate, is able to grow using arsenic instead of phosphorus. This claim, and subsequent studies to evaluate GFAJ-1, has brought new attention to the question of whether arsenic can play an essential or sustaining role for living organisms. If true, this would be in stark contrast to the well known toxicity of this element and its ability to cause a number of diseases, including cancer of the skin, lung, bladder, liver, and kidney. However, while deadly at high doses, arsenic oxide is also an approved and effective chemotherapeutic drug for the treatment of acute promyelocytic leukemia (APL). This review examines the evidence that arsenic may be a beneficial nutrient at trace levels below the background to which living organisms are normally exposed. It also examines whether arsenic can be used to sustain organisms growing under high arsenic conditions, specifically the results from recent studies of arsenic biochemistry motivated by the report of GFAJ-1. Both of these topics are considered in the context of the toxicity of this element and its ability to cause cancer and other diseases, yet its Janus-faced ability to effectively treat APL.

  14. Arsenic in Food

    MedlinePlus

    ... 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, ...

  15. Toxic Substances Portal- Arsenic

    MedlinePlus

    ... plants combines with carbon and hydrogen to form organic arsenic compounds. Inorganic arsenic compounds are mainly used ... uses; it is still used in industrial applications. Organic arsenic compounds are used as pesticides, primarily on ...

  16. Arsenic, inorganic

    Integrated Risk Information System (IRIS)

    Arsenic , inorganic ; CASRN 7440 - 38 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  17. Concentrating Radioactivity

    ERIC Educational Resources Information Center

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  18. Simulated Radioactivity

    ERIC Educational Resources Information Center

    Boettler, James L.

    1972-01-01

    Describes the errors in the sugar-cube experiment related to radioactivity as described in Project Physics course. The discussion considers some of the steps overlooked in the experiment and generalizes the theory beyond the sugar-cube stage. (PS)

  19. Radioactivity Calculations

    ERIC Educational Resources Information Center

    Onega, Ronald J.

    1969-01-01

    Three problems in radioactive buildup and decay are presented and solved. Matrix algebra is used to solve the second problem. The third problem deals with flux depression and is solved by the use of differential equations. (LC)

  20. Concentrating Radioactivity

    ERIC Educational Resources Information Center

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  1. Radioactivity Calculations

    ERIC Educational Resources Information Center

    Onega, Ronald J.

    1969-01-01

    Three problems in radioactive buildup and decay are presented and solved. Matrix algebra is used to solve the second problem. The third problem deals with flux depression and is solved by the use of differential equations. (LC)

  2. Simulated Radioactivity

    ERIC Educational Resources Information Center

    Boettler, James L.

    1972-01-01

    Describes the errors in the sugar-cube experiment related to radioactivity as described in Project Physics course. The discussion considers some of the steps overlooked in the experiment and generalizes the theory beyond the sugar-cube stage. (PS)

  3. RESULTS FROM ANALYSIS OF THE FIRST AND SECOND STRIP EFFLUENT COALESCER ELEMENTS FROM RADIOACTIVE OPERATIONS OF THE MODULAR CAUSTIC-SIDE SOLVENT EXTRACTION UNIT

    SciTech Connect

    Peters, T.; Fondeur, F.; Fink, S.

    2011-06-28

    The coalescer elements for the Strip Effluent (SE) acid within the Modular Caustic-Side Solvent Extraction Unit (MCU) experienced elevated differential pressure drop during radioactive operations. Following the end of operations for the first Macrobatch campaign and soon after start of the second Macrobatch campaign, personnel removed the coalescer media and provided to Savannah River National Laboratory (SRNL) for diagnostic investigation of the causes of reduced flow. This report summarizes those studies. Two Strip Effluent (SE) coalescers were delivered to the Savannah River National Laboratory (SRNL). One was removed from the Modular Caustic-Side Solvent Extraction Unit (MCU) between processing of Macrobatch 1 and 2 (coalescer 'Alpha'), and the second was removed from MCU after processing of {approx}24,000 gallons of salt solution (coalescer 'Beta'). Both coalescers underwent the same general strip acid flush program to reduce the dose and were delivered to SRNL for analysis of potential occluding solids. Analysis of Coalescer Alpha indicates the presence of aluminum hydroxide solids and aluminosilicate solids, while analysis of Coalescer Beta indicates the presence of aluminum hydroxide solids, but no aluminosilicates. Leaching studies on sections of both coalescers were performed. The results indicate that the coalescers had different amounts of solids present on them at the time of removal. Finally, samples of free liquids retrieved from both coalescers indicate no excessive amounts of CSSX solvent present. Given the strip acid flushing that occurred in the SE coalescers, the solids we detected on the coalescers are probably indicative of a larger quantity of these solids present before the strip acid flushing. Under this scenario, the excessive pressure drops are due to the solids and not from organic fouling.

  4. Microbial interactions in the arsenic cycle: adoptive strategies and applications in environmental management.

    PubMed

    Dhuldhaj, Umesh Praveen; Yadav, Ishwar Chandra; Singh, Surendra; Sharma, Naveen Kumar

    2013-01-01

    Arsenic (As) is a nonessential element that is often present in plants and in other organisms. However, it is one of the most hazardous of toxic elements globally. In many parts of the world, arsenic contamination in groundwater is a serious and continuing threat to human health. Microbes play an important role in regulating the environmental fate of arsenic. Different microbial processes influence the biogeochemical cycling of arsenic in ways that affect the accumulation of different arsenic species in various ecosystem compartments. For example, in soil, there are bacteria that methylate arsenite to trimethylarsine gas, thereby releasing arsenic to the atmosphere.In marine ecosystems, microbes exist that can convert inorganic arsenicals to organic arsenicals (e.g., di- and tri-methylated arsenic derivatives, arsenocholine,arsenobetaine, arsenosugars, arsenolipids). The organo arsenicals are further metabolized to complete the arsenic cycle.Microbes have developed various strategies that enable them to tolerate arsenic and to survive in arsenic-rich environments. Such strategies include As exclusion from cells by establishing permeability barrier, intra- and extracellular sequestration,active efflux pumps, enzymatic reduction, and reduction in the sensitivity of cellular targets. These strategies are used either singly or in combination. In bacteria,the genes for arsenic resistance/detoxification are encoded by the arsenic resistance operons (ars operon).In this review, we have addressed and emphasized the impact of different microbial processes (e.g., arsenite oxidation, cytoplasmic arsenate reduction, respiratory arsenate reduction, arsenite methylation) on the arsenic cycle. Microbes are the only life forms reported to exist in heavy arsenic-contaminated environments. Therefore,an understanding of the strategies adopted by microbes to cope with arsenic stress is important in managing such arsenic-contaminated sites. Further future insights into the different

  5. Tracing the source of sedimentary organic carbon in the Loess Plateau of China: An integrated elemental ratio, stable carbon signatures, and radioactive isotopes approach.

    PubMed

    Liu, Chun; Dong, Yuting; Li, Zhongwu; Chang, Xiaofeng; Nie, Xiaodong; Liu, Lin; Xiao, Haibing; Bashir, Hassan

    2017-02-01

    Soil erosion, which will induce the redistribution of soil and associated soil organic carbon (SOC) on the Earth's surface, is of critically importance for biogeochemical cycling of essential elements and terrestrial carbon sequestration. Despite the importance of soil erosion, surprisingly few studies have evaluated the sources of eroded carbon (C). This study used natural abundance levels of the stable isotope signature ((13)C) and radioactive isotopes ((137)Cs and (210)Pbex), along with elements ratio (C/N) based on a two end member mixing model to qualitatively and quantitatively identify the sources of sedimentary OC retained by check dam in the Qiaozigou small watershed in the Loess Plateau, China. Sediment profiles (0-200 cm) captured at natural depositional area of the basin was compared to possible source materials, which included: superficial Loess mineral soils (0-20 cm) from three land use types [i.e., grassland (Medicago sativa), forestland (Robinia pseudoacacia.), shrubland (Prunus sibirica), and gully land (Loess parent material.)]. The results demonstrated that SOC in sediments showed significantly negative correlation with pH (P < 0.01), and positive correlation with soil water content (SWC) (P < 0.05). The sedimentary OC was not derived from grasslands or gullies. Forestland and shrubland were two main sources of eroded organic carbon within the surface sediment (0-60 cm deep), except for that in the 20-40 cm soil layer. Radionuclides analyses also implied that the surface sediments retained by check-dams mainly originated from soils of forestland and shrubland. Results of the two end-member mixing model demonstrated that more than 50% SOC (mean probability estimate (MPE) 50.13% via (13)C and 60.53% via C/N) in surface sediment (0-20 cm deep) derived from forestland, whereas subsurface sedimentary SOC (20-200 cm) mainly resulted from shrubland (MPE > 50%). Although uncertainties on the sources of SOC in deep soils exist, the soil

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

    PubMed

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

    2016-03-23

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

  7. Arsenic and selenium in microbial metabolism

    USGS Publications Warehouse

    Stolz, John F.; Basu, Partha; Santini, Joanne M.; Oremland, Ronald S.

    2006-01-01

    Arsenic and selenium are readily metabolized by prokaryotes, participating in a full range of metabolic functions including assimilation, methylation, detoxification, and anaerobic respiration. Arsenic speciation and mobility is affected by microbes through oxidation/reduction reactions as part of resistance and respiratory processes. A robust arsenic cycle has been demonstrated in diverse environments. Respiratory arsenate reductases, arsenic methyltransferases, and new components in arsenic resistance have been recently described. The requirement for selenium stems primarily from its incorporation into selenocysteine and its function in selenoenzymes. Selenium oxyanions can serve as an electron acceptor in anaerobic respiration, forming distinct nanoparticles of elemental selenium that may be enriched in (76)Se. The biogenesis of selenoproteins has been elucidated, and selenium methyltransferases and a respiratory selenate reductase have also been described. This review highlights recent advances in ecology, biochemistry, and molecular biology and provides a prelude to the impact of genomics studies.

  8. Homicidal arsenic poisoning.

    PubMed

    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.

  9. Stability of arsenic peptides in plant extracts: off-line versus on-line parallel elemental and molecular mass spectrometric detection for liquid chromatographic separation.

    PubMed

    Bluemlein, Katharina; Raab, Andrea; Feldmann, Jörg

    2009-01-01

    The instability of metal and metalloid complexes during analytical processes has always been an issue of an uncertainty regarding their speciation in plant extracts. Two different speciation protocols were compared regarding the analysis of arsenic phytochelatin (As(III)PC) complexes in fresh plant material. As the final step for separation/detection both methods used RP-HPLC simultaneously coupled to ICP-MS and ES-MS. However, one method was the often used off-line approach using two-dimensional separation, i.e. a pre-cleaning step using size-exclusion chromatography with subsequent fraction collection and freeze-drying prior to the analysis using RP-HPLC-ICP-MS and/or ES-MS. This approach revealed that less than 2% of the total arsenic was bound to peptides such as phytochelatins in the root extract of an arsenate exposed Thunbergia alata, whereas the direct on-line method showed that 83% of arsenic was bound to peptides, mainly as As(III)PC(3) and (GS)As(III)PC(2). Key analytical factors were identified which destabilise the As(III)PCs. The low pH of the mobile phase (0.1% formic acid) using RP-HPLC-ICP-MS/ES-MS stabilises the arsenic peptide complexes in the plant extract as well as the free peptide concentration, as shown by the kinetic disintegration study of the model compound As(III)(GS)(3) at pH 2.2 and 3.8. But only short half-lives of only a few hours were determined for the arsenic glutathione complex. Although As(III)PC(3) showed a ten times higher half-life (23 h) in a plant extract, the pre-cleaning step with subsequent fractionation in a mobile phase of pH 5.6 contributes to the destabilisation of the arsenic peptides in the off-line method. Furthermore, it was found that during a freeze-drying process more than 90% of an As(III)PC(3) complex and smaller free peptides such as PC(2) and PC(3) can be lost. Although the two-dimensional off-line method has been used successfully for other metal complexes, it is concluded here that the fractionation and

  10. Arsenic exposure and cardiovascular disorders: an overview.

    PubMed

    Balakumar, Pitchai; Kaur, Jagdeep

    2009-12-01

    The incidence of arsenic toxicity has been observed in various countries including Taiwan, Bangladesh, India, Argentina, Australia, Chile, China, Hungary, Peru, Thailand, Mexico and United States of America. Arsenic is a ubiquitous element present in drinking water, and its exposure is associated with various cardiovascular disorders. Arsenic exposure plays a key role in the pathogenesis of vascular endothelial dysfunction as it inactivates endothelial nitric oxide synthase, leading to reduction in the generation and bioavailability of nitric oxide. In addition, the chronic arsenic exposure induces high oxidative stress, which may affect the structure and function of cardiovascular system. Further, the arsenic exposure has been noted to induce atherosclerosis by increasing the platelet aggregation and reducing fibrinolysis. Moreover, arsenic exposure may cause arrhythmia by increasing the QT interval and accelerating the cellular calcium overload. The chronic exposure to arsenic upregulates the expression of tumor necrosis factor-alpha, interleukin-1, vascular cell adhesion molecule and vascular endothelial growth factor to induce cardiovascular pathogenesis. The present review critically discussed the detrimental role of arsenic in the cardiovascular system.

  11. Mechanism of Arsenic Adsorption Using Wheat Biomass -- a spectroscopic study

    NASA Astrophysics Data System (ADS)

    Calvo, Oscar; Manciu, Felicia; Maldonado, Josefina; Gardea-Torresdey, Jorge

    2006-10-01

    Arsenic is a trace element that is toxic to animals, humans included. Since the current Environmental Protection Agency guidelines regarding water quality standards indicate that arsenic concentrations in excess of 50 ppb are hazardous to welfare of humans, the search for new water remediation methods or improvements of previous methods have been a focus in environmental technology. Investigations of arsenic uptake have used wide range of sorbents including iron oxides and oxyhydroxides, for which it have been proved that arsenic shows high affinity. In this study, we used far-infrared spectroscopy to examine the arsenic reduction using biomaterials. pH dependence analysis by FTIR demonstrates the sorption of iron oxides and oxyhydroxides by the wheat biomass. The splitting of 350 cm-1 amorphous iron oxide vibrations is a direct proof of the arsenic uptake. In addition, there is evidence of sorption of arsenic at sulfhydryl group of cysteine existent in wheat.

  12. RADIOACTIVE BATTERY

    DOEpatents

    Birden, J.H.; Jordan, K.C.

    1959-11-17

    A radioactive battery which includes a capsule containing the active material and a thermopile associated therewith is presented. The capsule is both a shield to stop the radiations and thereby make the battery safe to use, and an energy conventer. The intense radioactive decay taking place inside is converted to useful heat at the capsule surface. The heat is conducted to the hot thermojunctions of a thermopile. The cold junctions of the thermopile are thermally insulated from the heat source, so that a temperature difference occurs between the hot and cold junctions, causing an electrical current of a constant magnitude to flow.

  13. Arsenic surveillance program

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Background information about arsenic is presented including forms, common sources, and clinical symptoms of arsenic exposure. The purpose of the Arsenic Surveillance Program and LeRC is outlined, and the specifics of the Medical Surveillance Program for Arsenic Exposure at LeRC are discussed.

  14. Determination of total arsenic, inorganic and organic arsenic species in wine.

    PubMed

    Herce-Pagliai, C; Moreno, I; González, G; Repetto, M; Cameán, A M

    2002-06-01

    Forty-five wine samples from the south of Spain of different alcoholic strength were analysed for total arsenic and its inorganic [As(III), As(V)] and organic (monomethylarsonic acid [MMAA], dimethylarsinic acid [DMAA]) species. The As levels of the wine samples ranged from 2.1 to 14.6 microg l(-1). The possible effect of the alcoholic fermentation process on the levels of the total arsenic and arsenical species was studied. The average total arsenic levels for the different samples were very similar, without significant differences between all types of wines. In table wines and sherry, the percentages of total inorganic arsenic were 18.6 and 15.6%, with DMAA or MMAA being the predominant species, respectively. In most samples, DMAA was the most abundant species, but the total inorganic aresenic fraction was considerable, representing 25.4% of the total concentration of the element. The estimated daily intakes of total arsenic and total inorganic arsenic for average Spanish consumers were 0.78 and 0.15 microg/person day(-1), respectively. The results suggest that the consumption of these types of wines makes no significant contribution to the total and inorganic arsenic intake for normal drinkers. However, wine consumption contributes a higher arsenic intake than through consumption of beers and sherry brandies.

  15. Toxic Elements in Soil and Groundwater: Short-Time Study on Electrokinetic Removal of Arsenic in the Presence of other Ions

    PubMed Central

    Leszczynska, Danuta; Ahmad, Hafiz

    2006-01-01

    The electrokinetic technique is an emerging technology presently tested in situ to remove dissolved heavy metals from contaminated groundwater. There is a growing interest for using this system to cleanse clayey soil contaminated by toxic metallic ions. Currently, there are very few available non-destructive treatment methods that could be successfully applied in situ on low permeable type of soil matrix. The main objective of presented study was to validate and possibly enhance the overall efficiency of decontamination by the electrokinetic technique of the low permeable soil polluted by the arsenic in combination with chromium and copper ions. The chosen mixture of ions was imitating leak of pesticide well known as chromate copper arsenate (CCA). The chosen technique is showing a big promise to be used in the future as a portable, easy to install and run on sites with spills or leaks hard to reach otherwise; such as in the dense populated and urbanized areas. Laboratory electrokinetic experiments were designed to understand and possibly manipulate main mechanisms involved during forced migration of ions. All tests were conducted on artificially contaminated kaolinite (low permeable clay soil). Electrokinetic migration was inducted by the low voltage dc current applied through soil column. Series of experiments were designed to assess the efficiency of arsenic-chromium-copper remediation by applying (1) only dc current; and (2) by altering the soil environment. Obtained results showed that arsenic could be successfully removed from the soil in one day (25 hours) span. It was significant time reduction, very important during emergency response. Mass recovered at the end of each test depended on initial condition of soil and type of flushing solution. The best results were obtained, when soil was flushed with either NaOH or NaOCl (total removal efficiency 74.4% and 78.1%, respectively). Direct analysis of remained arsenic in soil after these tests confirmed

  16. Comparison of extraction procedures for the determination of arsenic and other elements in lobster tissue by inductively coupled plasma mass spectrometry.

    PubMed

    Brisbin, Judith A; Caruso, Joseph A

    2002-07-01

    A variety of extraction procedures were evaluated for the extraction of arsenic and other analytes from lobster tissue samples using inductively coupled plasma mass spectrometry (ICP-MS) detection. Soxhlet, room temperature mixing, sonication, microwave assisted, supercritical carbon dioxide and subcritical water extractions were evaluated for a variety of solvent systems and optimum conditions determined using a partially defatted Lobster Hepatopancreas marine certified reference material, TORT-2 (National Research Council of Canada). The solubility trends and solvents into which the analytes extracted gave an indication as to the polar/non-polar nature of the compounds present. Analytes that prefer water are probably more polar or inorganic, while those preferring methanol solutions are less polar or organic in nature. Arsenic, cadmium, cobalt, molybdenum and selenium were probably all present in TORT-2 in both polar inorganic and non-polar organic forms. While TORT-2 may have contained similar amounts of selenium in both forms, the results suggested that more of the arsenic was present as less polar or more organic compounds, and cobalt existed mainly as more polar or inorganic species. Most of the extraction techniques suggested that, although there may be some less polar organic forms present, more of the cadmium was probably present as polar inorganic compounds. Additionally, most techniques indicated that molybdenum was possibly all less polar or more organic in nature. In general, microwave assisted extraction (MAE) yielded comparable or improved recoveries for all of the analytes monitored and usually required less solvent. Additionally, MAE proved to be the mildest, fastest, least complicated and most reproducible extraction technique evaluated. MAE at 75 degrees C for 2 min exposure time yielded quantitative recovery of arsenic from TORT-2. These conditions were evaluated for lobster tissue samples purchased from a local restaurant. Separate evaluation

  17. Radioactive Waste.

    ERIC Educational Resources Information Center

    Blaylock, B. G.

    1978-01-01

    Presents a literature review of radioactive waste disposal, covering publications of 1976-77. Some of the studies included are: (1) high-level and long-lived wastes, and (2) release and burial of low-level wastes. A list of 42 references is also presented. (HM)

  18. Radioactive Waste.

    ERIC Educational Resources Information Center

    Blaylock, B. G.

    1978-01-01

    Presents a literature review of radioactive waste disposal, covering publications of 1976-77. Some of the studies included are: (1) high-level and long-lived wastes, and (2) release and burial of low-level wastes. A list of 42 references is also presented. (HM)

  19. Arsenic in the geosphere--a review.

    PubMed

    Matschullat, J

    2000-04-17

    An attempt is made to quantify the global element cycle for arsenic, based on an extensive literature research with special emphasis on the most recent works. Reservoirs in and fluxes within and through lithosphere, atmosphere, pedosphere, hydrosphere, biosphere, and anthrosposphere are being presented. Crucial knowledge gaps are addressed and some simple model calculations partially question currently held ideas about sources, pathways, and the fate of arsenic in the environment.

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

    PubMed

    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.

  1. THE CELLUAR METABOLISM OF ARSENIC

    EPA Science Inventory

    Because the methylation of arsenic produces intermediates and terminal products that exceed inorganic arsenic in potency as enzyme inhibitors, cytotoxins, and genotoxins, the methylation of arsenic is properly regarded as an activation process. The methylation of arsenic is an e...

  2. THE CELLUAR METABOLISM OF ARSENIC

    EPA Science Inventory

    Because the methylation of arsenic produces intermediates and terminal products that exceed inorganic arsenic in potency as enzyme inhibitors, cytotoxins, and genotoxins, the methylation of arsenic is properly regarded as an activation process. The methylation of arsenic is an e...

  3. Feasibility of Water Treatment Technologies for Arsenic and Fluoride Removal

    DTIC Science & Technology

    2004-11-17

    1 Feasibility of Water Treatment Technologies for Arsenic and Fluoride Removal AWWA Water Quality Technology Conference 17 November 2004; Arsenic I...Brian C. Pickard, P.E., R.S. U.S. Army Center for Health Promotion and Preventive Medicine Aberdeen Proving Ground, MD Muhammad Bari, P.E. Chief...Technologies for Arsenic and Fluoride Removal 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK

  4. Chem I Supplement: Arsenic and Old Myths.

    ERIC Educational Resources Information Center

    Sarquis, Mickey

    1979-01-01

    Describes the history of arsenic, the properties of arsenic, production and uses of arsenicals, arsenic in the environment; toxic levels of arsenic, arsenic in the human body, and the Marsh Test. (BT)

  5. Chem I Supplement: Arsenic and Old Myths.

    ERIC Educational Resources Information Center

    Sarquis, Mickey

    1979-01-01

    Describes the history of arsenic, the properties of arsenic, production and uses of arsenicals, arsenic in the environment; toxic levels of arsenic, arsenic in the human body, and the Marsh Test. (BT)

  6. Massive acute arsenic poisonings.

    PubMed

    Lech, Teresa; Trela, Franciszek

    2005-07-16

    Arsenic poisonings are still important in the field of toxicology, though they are not as frequent as about 20-30 years ago. In this paper, the arsenic concentrations in ante- and post-mortem materials, and also forensic and anatomo-pathological aspects in three cases of massive acute poisoning with arsenic(III) oxide (two of them with unexplained criminalistic background, in which arsenic was taken for amphetamine and one suicide), are presented. Ante-mortem blood and urine arsenic concentrations ranged from 2.3 to 6.7 microg/ml, respectively. Post-mortem tissue total arsenic concentrations were also detected in large concentrations. In case 3, the contents of the duodenum contained as much as 30.1% arsenic(III) oxide. The high concentrations of arsenic detected in blood and tissues in all presented cases are particularly noteworthy in that they are very rarely detected at these concentrations in fatal arsenic poisonings.

  7. Geochemical anomalies of toxic elements and arsenic speciation in airborne particles from Cu mining and smelting activities: influence on air quality.

    PubMed

    Sánchez de la Campa, Ana M; Sánchez-Rodas, Daniel; González Castanedo, Yolanda; de la Rosa, Jesús D

    2015-06-30

    A characterization of chemical composition and source contribution of PM10 in three representative environments of southwest Spain related to mining activities (mineral extraction, mining waste and Cu-smelting) has been performed. A study of geochemical anomalies was conducted in the samples collected at the three stations between July 2012 and October 2013. The influence of Cu-smelting processes was compared to other mining activities, where common tracers were identified. The Cu and As concentrations in the study area are higher than in other rural and urban stations of Spain, in which geochemical anomalies of As, Se, Bi, Cd, and Pb have been reported. The results of source contribution showed similar geochemical signatures in the industrial and mining factors. However, the contribution to PM10 is different according to the type of industrial activity. These results have been confirmed performing an arsenic speciation analysis of the PM10 samples, in which the mean extraction efficiency of arsenic depended on the origin of the samples. These finding indicate that the atmospheric particulate matter emitted from Cu-smelting has a high residence time in the atmosphere. This indicates that the Cu-smelter can impact areas of high ecological interest and considered as clean air.

  8. The ecology of arsenic

    USGS Publications Warehouse

    Oremland, Ronald S.; Stolz, John F.

    2003-01-01

    Arsenic is a metalloid whose name conjures up images of murder. Nonetheless, certain prokaryotes use arsenic oxyanions for energy generation, either by oxidizing arsenite or by respiring arsenate. These microbes are phylogenetically diverse and occur in a wide range of habitats. Arsenic cycling may take place in the absence of oxygen and can contribute to organic matter oxidation. In aquifers, these microbial reactions may mobilize arsenic from the solid to the aqueous phase, resulting in contaminated drinking water. Here we review what is known about arsenic-metabolizing bacteria and their potential impact on speciation and mobilization of arsenic in nature.

  9. MARE: Mars Radioactivity Experiment

    NASA Astrophysics Data System (ADS)

    di Lellis, A. M.; Capria, M. T.; Espinasse, S.; Magni, G.; Orosei, R.; Piccioni, G.; Federico, C.; Minelli, G.; Pauselli, C.; Scarpa, G.

    1999-09-01

    MARE is an experiment for the measurement of the beta and gamma radioactivity in space and in the Martian soil, both at the surface and in the subsurface. This will be accomplished by means of a dosimeter and a spectrometer. The radiation dose rate to which crews will be exposed is one of the hazards that has to be quantified before the human exploration of Mars may begin. Data for evaluating radioactivity levels at Martian surface are of great interest for environmental studies related to life in general. The dosimeter will be able to measure the beta and gamma radiation dose received, with a responsivity which is very close to that of a living organism. The dosimeter is based on thermo-luminescence pills which emit an optical signal proportional to the absorbed dose when heated. Radioactive elements ((40) K, (235) U, (238) U and (232) Th) can be used as a mean of tracing the evolution of a terrestrial planet. These radioactive elements are the source of the internal heat, which drives convection in the mantle. They have been redistributed in this process and they are now concentrated in the crust where they are accessible for study. Their different behavior during the fractionation process can be used as a mean to investigate the geochemical characteristic of Mars. The spectrometer, a scintillation radiation absorber system for single event counting, is capable of detecting gamma photons with energies between 200 KeV and 10 MeV. The detected events will be processed in such a way to allow the recognition of the spectral signature of different decay processes, and thus the identification and the measurement of the concentrations of different radionuclides in the Martian soil.

  10. Arsenic and cardiovascular disease.

    PubMed

    States, J Christopher; Srivastava, Sanjay; Chen, Yu; Barchowsky, Aaron

    2009-02-01

    Chronic arsenic exposure is a worldwide health problem. Although arsenic-induced cancer has been widely studied, comparatively little attention has been paid to arsenic-induced vascular disease. Epidemiological studies have shown that chronic arsenic exposure is associated with increased morbidity and mortality from cardiovascular disease. In addition, studies suggest that susceptibility to arsenic-induced vascular disease may be modified by nutritional factors in addition to genetic factors. Recently, animal models for arsenic-induced atherosclerosis and liver sinusoidal endothelial cell dysfunction have been developed. Initial studies in these models show that arsenic exposure accelerates and exacerbates atherosclerosis in apolipoprotein E-knockout mice. Microarray studies of liver mRNA and micro-RNA abundance in mice exposed in utero suggest that a permanent state of stress is induced by the arsenic exposure. Furthermore, the livers of the arsenic-exposed mice have activated pathways involved in immune responses suggesting a pro-hyperinflammatory state. Arsenic exposure of mice after weaning shows a clear dose-response in the extent of disease exacerbation. In addition, increased inflammation in arterial wall is evident. In response to arsenic-stimulated oxidative signaling, liver sinusoidal endothelium differentiates into a continuous endothelium that limits nutrient exchange and waste elimination. Data suggest that nicotinamide adenine dinucleotide phosphate oxidase-derived superoxide or its derivatives are essential second messengers in the signaling pathway for arsenic-stimulated vessel remodeling. The recent findings provide future directions for research into the cardiovascular effects of arsenic exposure.

  11. Arsenic stress after the Proterozoic glaciations.

    PubMed

    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.

  12. Arsenic stress after the Proterozoic glaciations

    PubMed Central

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

    2015-01-01

    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. PMID:26635187

  13. Arsenic stress after the Proterozoic glaciations

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

    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.

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

    PubMed

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

    2003-09-01

    Arsenic, a carcinogenic trace element, threatens not only the health of millions of humans and other living organisms, but also global sustainability. We present here, for the first time, the global industrial-age cumulative anthropogenic arsenic production and its potential accumulation and risks in the environment. In 2000, the world cumulative industrial-age anthropogenic arsenic production was 4.53 million tonnes. The world-wide coal and petroleum industries accounted for 46% of global annual gross arsenic production, and their overall contribution to industrial-age gross arsenic production was 27% in 2000. Global industrial-age anthropogenic As sources (as As cumulative production) follow the order: As mining production>As generated from coal>As generated from petroleum. The potential industrial-age anthropogenic arsenic input in world arable surface in 2000 was 2.18 mg arsenic kg(-1), which is 1.2 times that in the lithosphere. The development of substitute materials for arsenic applications in the agricultural and forestry industries and controls of arsenic emissions from the coal industry may be possible strategies to significantly decrease arsenic pollution sources and dissipation rates into the environment.

  15. Simultaneous depth-profiling of electrical and elemental properties of ion-implanted arsenic in silicon by combining secondary-ion mass spectrometry with resistivity measurements

    NASA Astrophysics Data System (ADS)

    Bennett, N. S.; Wong, C. S.; McNally, P. J.

    2016-07-01

    A method is proposed to extract the electrical data for surface doping profiles of semiconductors in unison with the chemical profile acquired by secondary-ion mass spectrometry (SIMS)—a method we call SIMSAR (secondary-ion mass spectrometry and resistivity). The SIMSAR approach utilizes the inherent sputtering process of SIMS, combined with sequential four-point van der Pauw resistivity measurements, to surmise the active doping profile as a function of depth. The technique is demonstrated for the case of ion-implanted arsenic doping profiles in silicon. Complications of the method are identified, explained, and corrections for these are given. While several techniques already exist for chemical dopant profiling and numerous for electrical profiling, since there is no technique which can measure both electrical and chemical profiles in parallel, SIMSAR has significant promise as an extension of the conventional dynamic SIMS technique, particularly for applications in the semiconductor industry.

  16. Simultaneous depth-profiling of electrical and elemental properties of ion-implanted arsenic in silicon by combining secondary-ion mass spectrometry with resistivity measurements.

    PubMed

    Bennett, N S; Wong, C S; McNally, P J

    2016-07-01

    A method is proposed to extract the electrical data for surface doping profiles of semiconductors in unison with the chemical profile acquired by secondary-ion mass spectrometry (SIMS)-a method we call SIMSAR (secondary-ion mass spectrometry and resistivity). The SIMSAR approach utilizes the inherent sputtering process of SIMS, combined with sequential four-point van der Pauw resistivity measurements, to surmise the active doping profile as a function of depth. The technique is demonstrated for the case of ion-implanted arsenic doping profiles in silicon. Complications of the method are identified, explained, and corrections for these are given. While several techniques already exist for chemical dopant profiling and numerous for electrical profiling, since there is no technique which can measure both electrical and chemical profiles in parallel, SIMSAR has significant promise as an extension of the conventional dynamic SIMS technique, particularly for applications in the semiconductor industry.

  17. Arsenic in water treatment.

    SciTech Connect

    Siegel, Malcolm Dean

    2004-12-01

    Sandia National Laboratories (SNL) is collaborating with the Awwa Research Foundation (AwwaRF) and WERC (A Consortium for Environmental Education and Technology Development) in a program for the development and testing of innovative technologies that have the potential to substantially reduce the costs associated with arsenic removal from drinking water. Sandia National Laboratories will administer contracts placed with AwwaRF and WERC to carry out bench scale studies and economic analyses/outreach activities, respectively. The elements of the AwwaRF program include (1) identification of new technologies, (2) proof-of-concept laboratory studies and, (3) a research program that will meet the other needs of small utilities by providing solutions to small utilities so that they may successfully meet the new arsenic MCL. WERC's activities will include development of an economic analysis tool for Pilot Scale Demonstrations and development of educational training and technical assistance tools. The objective of the Sandia Program is the field demonstration testing of innovative technologies. The primary deliverables of the Sandia program will be engineering analyses of candidate technologies; these will be contained in preliminary reports and final analysis reports. Projected scale-up costs will be generated using a cost model provided by WERC or another suitable model.

  18. Arsenic Trioxide Injection

    MedlinePlus

    ... of the white blood cells).Arsenic trioxide may cause a serious or life-threatening group of symptoms ... medications to treat the syndrome.Arsenic trioxide may cause QT prolongation (heart muscles take longer to recharge ...

  19. Arsenic Treatment Technology Demonstrations

    EPA Pesticide Factsheets

    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. Reduction and Coordination of Arsenic in Indian Mustard1

    PubMed Central

    Pickering, Ingrid J.; Prince, Roger C.; George, Martin J.; Smith, Robert D.; George, Graham N.; Salt, David E.

    2000-01-01

    The bioaccumulation of arsenic by plants may provide a means of removing this element from contaminated soils and waters. However, to optimize this process it is important to understand the biological mechanisms involved. Using a combination of techniques, including x-ray absorption spectroscopy, we have established the biochemical fate of arsenic taken up by Indian mustard (Brassica juncea). After arsenate uptake by the roots, possibly via the phosphate transport mechanism, a small fraction is exported to the shoot via the xylem as the oxyanions arsenate and arsenite. Once in the shoot, the arsenic is stored as an AsIII-tris-thiolate complex. The majority of the arsenic remains in the roots as an AsIII-tris-thiolate complex, which is indistinguishable from that found in the shoots and from AsIII-tris-glutathione. The thiolate donors are thus probably either glutathione or phytochelatins. The addition of the dithiol arsenic chelator dimercaptosuccinate to the hydroponic culture medium caused a 5-fold-increased arsenic level in the leaves, although the total arsenic accumulation was only marginally increased. This suggests that the addition of dimercaptosuccinate to arsenic-contaminated soils may provide a way to promote arsenic bioaccumulation in plant shoots, a process that will be essential for the development of an efficient phytoremediation strategy for this element. PMID:10759512

  1. NIOSH Method 9102: Elements on Wipes

    EPA Pesticide Factsheets

    Method 9102 describes procedures for analysis of elements, including arsenic, vanadium, osmium, thallium and titanium, on wipe samples using inductively coupled plasma (ICP) – atomic emission spectrometry (AES).

  2. ARSENIC SOURCES AND ASSESSMENT

    EPA Science Inventory

    Recent research has identified a number of potential and current links between environmental arsenic releases and the management of operational and abandoned landfills. Many landfills will receive an increasing arsenic load due to the disposal of arsenic-bearing solid residuals ...

  3. ARSENIC REMOVAL TECHNOLOGY

    EPA Science Inventory

    Presentation will discuss the state-of-art technology for removal of arsenic from drinking water. Presentation includes results of several EPA field studies on removal of arsenic from existing arsenic removal plants and key results from several EPA sponsored research studies. T...

  4. ARSENIC REMOVAL TECHNOLOGY

    EPA Science Inventory

    Presentation will discuss the state-of-art technology for removal of arsenic from drinking water. Presentation includes results of several EPA field studies on removal of arsenic from existing arsenic removal plants and key results from several EPA sponsored research studies. T...

  5. ARSENIC SOURCES AND ASSESSMENT

    EPA Science Inventory

    Recent research has identified a number of potential and current links between environmental arsenic releases and the management of operational and abandoned landfills. Many landfills will receive an increasing arsenic load due to the disposal of arsenic-bearing solid residuals ...

  6. ARSENIC TREATMENT TECHNOLOGY

    EPA Science Inventory

    Presentation will discuss the state-of-the-art technology for removal of arsenic from drinking water. Presentation also includes results of several EPA field studies on removal of arsenic from existing arsenic removal plants and key results from several EPA sponsored research st...

  7. Case studies--arsenic.

    PubMed

    Chou, C H Selene J; De Rosa, Christopher T

    2003-08-01

    Arsenic is found naturally in the environment. People may be exposed to arsenic by eating food, drinking water, breathing air, or by skin contact with soil or water that contains arsenic. In the U.S., the diet is a predominant source of exposure for the general population with smaller amounts coming from drinking water and air. Children may also be exposed to arsenic because of hand to mouth contact or eating dirt. In addition to the normal levels of arsenic in air, water, soil, and food, people could by exposed to higher levels in several ways such as in areas containing unusually high natural levels of arsenic in rocks which can lead to unusually high levels of arsenic in soil or water. People living in an area like this could take in elevated amounts of arsenic in drinking water. Workers in an occupation that involves arsenic production or use (for example, copper or lead smelting, wood treatment, pesticide application) could be exposed to elevated levels of arsenic at work. People who saw or sand arsenic-treated wood could inhale/ingest some of the sawdust which contains high levels of arsenic. Similarly, when pressure-treated wood is burned, high levels of arsenic could be released in the smoke. In agricultural areas where arsenic pesticides were used on crops the soil could contain high levels of arsenic. Some hazardous waste sites contain large quantities of arsenic. Arsenic ranks #1 on the ATSDR/EPA priority list of hazardous substances. Arsenic has been found in at least 1,014 current or former NPL sites. At the hazardous waster sites evaluated by ATSDR, exposure to arsenic in soil predominated over exposure to water, and no exposure to air had been recorded. However, there is no information on morbidity or mortality from exposure to arsenic in soil at hazardous waste sites. Exposure assessment, community and tribal involvement, and evaluation and surveillance of health effects are among the ATSDR future Superfund research program priority focus areas

  8. Radioactive nondestructive test method

    NASA Technical Reports Server (NTRS)

    Obrien, J. R.; Pullen, K. E.

    1971-01-01

    Various radioisotope techniques were used as diagnostic tools for determining the performance of spacecraft propulsion feed system elements. Applications were studied in four tasks. The first two required experimental testing involving the propellant liquid oxygen difluoride (OF2): the neutron activation analysis of dissolved or suspended metals, and the use of radioactive tracers to evaluate the probability of constrictions in passive components (orifices and filters) becoming clogged by matter dissolved or suspended in the OF2. The other tasks were an appraisal of the applicability of radioisotope techniques to problems arising from the exposure of components to liquid/gas combinations, and an assessment of the applicability of the techniques to other propellants.

  9. Radioactive waste material disposal

    DOEpatents

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

    1995-10-24

    The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide. 3 figs.

  10. Radioactive waste material disposal

    DOEpatents

    Forsberg, Charles W.; Beahm, Edward C.; Parker, George W.

    1995-01-01

    The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide.

  11. Arsenic speciation in tissues of the Mediterranean polychaete Sabella spallanzanii.

    PubMed

    Fattorini, Daniele; Regoli, Francesco

    2004-08-01

    Arsenic toxicity is strictly related to its chemical form and marine organisms are known to accumulate this element mostly as organoarsenic nontoxic molecules. Contrasting with this general trend, the presence of moderately toxic to toxic arsenic compounds recently has been reported in some polychaete species, showing a completely different profile of represented chemical species. In this work the presence and distribution of arsenic were characterized in the Mediterranean polychaete Sabella spallanzanii, by analyzing total levels in different tissues and subcellular fractions and the occurrence of various arsenical compounds. Further investigations on arsenic accumulation in S. spallanzanii were based on the capability of this species to regenerate the branchial crown both in laboratory and field conditions. Though basal levels of arsenic in the thorax were similar to those already described for most polychaetes and invertebrate species, branchial crown revealed a remarkable accumulation of this element with concentrations higher than 1000 microg/g. Arsenic mainly was localized in a soluble form within the cytosol and dimethyl-arsinate (DMA) appeared the most represented chemical species. Experiments on bioaccumulation of arsenic in regenerating branchial crowns confirmed the environmental origin of this element and the time-dependent appearance of various As compounds suggested a methylation pathway more than a degradation process for the elevated content of DMA. The accumulation of this moderately toxic compound in the more vulnerable tissues of the polychaete might represent an antipredatory strategy, as indicated by some feeding trials where fish ate the thorax but rejected the branchial crowns.

  12. Arsenic removal from water

    DOEpatents

    Moore, Robert C.; Anderson, D. Richard

    2007-07-24

    Methods for removing arsenic from water by addition of inexpensive and commonly available magnesium oxide, magnesium hydroxide, calcium oxide, or calcium hydroxide to the water. The hydroxide has a strong chemical affinity for arsenic and rapidly adsorbs arsenic, even in the presence of carbonate in the water. Simple and commercially available mechanical methods for removal of magnesium hydroxide particles with adsorbed arsenic from drinking water can be used, including filtration, dissolved air flotation, vortex separation, or centrifugal separation. A method for continuous removal of arsenic from water is provided. Also provided is a method for concentrating arsenic in a water sample to facilitate quantification of arsenic, by means of magnesium or calcium hydroxide adsorption.

  13. Arsenic: homicidal intoxication

    SciTech Connect

    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.

  14. Arsenic geochemistry and health.

    PubMed

    Duker, Alfred A; Carranza, E J M; Hale, Martin

    2005-07-01

    Arsenic occurs naturally in the earth's crust and is widely distributed in the environment. Natural mineralization and activities of microorganisms enhance arsenic mobilization in the environment but human intervention has exacerbated arsenic contamination. Although arsenic is useful for industrial, agricultural, medicinal and other purposes, it exerts a toxic effect in a variety of organisms, including humans. Arsenic exposure may not only affect and disable organs of the body, especially the skin, but may also interfere with the proper functioning of the immune system. This paper, therefore, generally highlights the toxic effects of arsenic as well as its mobilization in the natural environment and possible controls. It also briefly attempts to outline the impact of arsenic on the immune system, whose alteration could lead to viral/bacterial infections.

  15. Thermal-electric coupled-field finite element modeling and experimental testing of high-temperature ion sources for the production of radioactive ion beams

    SciTech Connect

    Manzolaro, M. Andrighetto, A.; Meneghetti, G.; Vivian, G.; D’Agostini, F.

    2016-02-15

    In isotope separation on line facilities the target system and the related ion source are two of the most critical components. In the context of the selective production of exotic species (SPES) project, a 40 MeV 200 μA proton beam directly impinges a uranium carbide target, generating approximately 10{sup 13} fissions per second. The radioactive isotopes produced in this way are then directed to the ion source, where they can be ionized and finally accelerated to the subsequent areas of the facility. In this work both the surface ion source and the plasma ion source adopted for the SPES facility are presented and studied by means of numerical thermal-electric models. Then, numerical results are compared with temperature and electric potential difference measurements, and finally the main advantages of the proposed simulation approach are discussed.

  16. Electrical-thermal-structural finite element simulation and experimental study of a plasma ion source for the production of radioactive ion beams

    SciTech Connect

    Manzolaro, M.; Andrighetto, A.; Meneghetti, G.; Vivian, G.

    2016-03-15

    The production target and the ion source constitute the core of the selective production of exotic species (SPES) facility. In this complex experimental apparatus for the production of radioactive ion beams, a 40 MeV, 200 μA proton beam directly impinges a uranium carbide target, generating approximately 10{sup 13} fissions per second. The transfer line enables the unstable isotopes generated by the {sup 238}U fissions in the target to reach the ion source, where they can be ionized and finally accelerated to the subsequent areas of the facility. In this work, the plasma ion source currently adopted for the SPES facility is analyzed in detail by means of electrical, thermal, and structural numerical models. Next, theoretical results are compared with the electric potential difference, temperature, and displacement measurements. Experimental tests with stable ion beams are also presented and discussed.

  17. Electrical-thermal-structural finite element simulation and experimental study of a plasma ion source for the production of radioactive ion beams.

    PubMed

    Manzolaro, M; Meneghetti, G; Andrighetto, A; Vivian, G

    2016-03-01

    The production target and the ion source constitute the core of the selective production of exotic species (SPES) facility. In this complex experimental apparatus for the production of radioactive ion beams, a 40 MeV, 200 μA proton beam directly impinges a uranium carbide target, generating approximately 10(13) fissions per second. The transfer line enables the unstable isotopes generated by the (238)U fissions in the target to reach the ion source, where they can be ionized and finally accelerated to the subsequent areas of the facility. In this work, the plasma ion source currently adopted for the SPES facility is analyzed in detail by means of electrical, thermal, and structural numerical models. Next, theoretical results are compared with the electric potential difference, temperature, and displacement measurements. Experimental tests with stable ion beams are also presented and discussed.

  18. Bioaccessibility and excretion of arsenic in Niu Huang Jie Du Pian pills

    SciTech Connect

    Koch, Iris; Sylvester, Steven; Lai, Vivian W.-M.; Owen, Andrew; Reimer, Kenneth J. Cullen, William R.

    2007-08-01

    Traditional Chinese medicines (TCMs) often contain significant levels of potentially toxic elements, including arsenic. Niu Huang Jie Du Pian pills were analyzed to determine the concentration, bioaccessibility (arsenic fraction soluble in the human gastrointestinal system) and chemical form (speciation) of arsenic. Arsenic excretion in urine (including speciation) and facial hair were studied after a one-time ingestion. The pills contained arsenic in the form of realgar, and although the total arsenic that was present in a single pill was high (28 mg), the low bioaccessibility of this form of arsenic predicted that only 4% of it was available for absorption into the bloodstream (1 mg of arsenic per pill). The species of arsenic that were solubilized were inorganic arsenate (As(V)) and arsenite (As(III)) but DMAA and MMAA were detected in urine. Two urinary arsenic excretion peaks were observed: an initial peak several (4-8) hours after ingestion corresponding to the excretion of predominantly As(III), and a larger peak at 14 h corresponding predominantly to DMAA and MMAA. No methylated As(III) species were observed. Facial hair analysis revealed that arsenic concentrations did not increase significantly as a result of the ingestion. Arsenic is incompletely soluble under human gastrointestinal conditions, and is metabolized from the inorganic to organic forms found in urine. Bioaccessible arsenic is comparable to the quantity excreted. Facial hair as a bio-indicator should be further tested.

  19. Distribution and hosts of arsenic in a sediment core from the Chianan Plain in SW Taiwan: Implications on arsenic primary source and release mechanisms.

    PubMed

    Yang, Huai-Jen; Lee, Chi-Yu; Chiang, Yu-Ju; Jean, Jiin-Shuh; Shau, Yen-Hong; Takazawa, Eiichi; Jiang, Wei-Teh

    2016-11-01

    High arsenic abundance of 50-700μg/L in the groundwater from the Chianan Plain in southwestern Taiwan is a well-known environmental hazard. The groundwater-associated sediments, however, have not been geochemically characterized, thus hindering a comprehensive understanding of arsenic cycling in this region. In this study, samples collected from a 250m sediment core at the centre of the Chianan Plain were analyzed for arsenic and TOC concentrations (N=158), constituent minerals (N=25), major element abundances (N=105), and sequential arsenic extraction (N=23). The arsenic data show a prevalence of >10mg/kg with higher concentrations of 20-50mg/kg concentrated at 60-80 and 195-210m. Arsenic was extracted mainly as an adsorbate on clay minerals, as a co-precipitate in amorphous iron oxyhydroxide, and as a structural component in clay minerals. Since the sediments consist mainly of quartz, chlorite, and illite, the correlations between arsenic concentration and abundances of K2O and MgO pinpoint illite and chlorite as the major arsenic hosts. The arsenic-total iron correlation reflects the role of chlorite along with the contribution from amorphous iron oxyhydroxide as indicated by arsenic extraction data. Organic matter is not the dominant arsenic host for low TOC content, low arsenic abundance extracted from it, and a relatively low R(2) of the arsenic-TOC correlation. The major constituent minerals in the sediments are the same as those of the upriver metapelites, establishing a sink-source relationship. Composition data from two deep groundwater samples near the sediment core show Eh values and As(V)/As(III) ratios of reducing environments and high arsenic, K, Mg, and Fe contents necessary for deriving arsenic from sediments by desorption from clay and dissolution of iron oxyhydroxide. Therefore, groundwater arsenic was mainly derived from groundwater-associated sediments with limited contributions from other sources, such as mud volcanoes.

  20. ARSENIC (+3 OXIDATION STATE) METHYLTRANSFERASE AND THE METHYLATION OF ARSENICALS

    EPA Science Inventory

    Metabolic conversion of inorganic arsenic into methylated products is a multistep process that yields mono, di, and trimethylated arsenicals. In recent years, it has become apparent that formation of methylated metabolites of inorganic arsenic is not necessarily a detoxification...

  1. ARSENIC (+3 OXIDATION STATE) METHYLTRANSFERASE AND THE METHYLATION OF ARSENICALS

    EPA Science Inventory

    Metabolic conversion of inorganic arsenic into methylated products is a multistep process that yields mono, di, and trimethylated arsenicals. In recent years, it has become apparent that formation of methylated metabolites of inorganic arsenic is not necessarily a detoxification...

  2. Emissions of air toxics from coal-fired boilers: Arsenic

    SciTech Connect

    Mendelsohn, M.H.; Huang, H.S.; Livengood, C.D.

    1994-08-01

    Concerns over emissions of hazardous air pollutants (air toxics) have emerged as a major environmental issue; the authority of the US Environmental Protection Agency to regulate such pollutants has been greatly expanded through passage of the Clean Air Act Amendments of 1990. Arsenic and arsenic compounds are of concern mainly because of their generally recognized toxicity. Arsenic is also regarded as one of the trace elements in coal subject to significant vaporization. This report summarizes and evaluates available published information on the arsenic content of coals mined in the United States, on arsenic emitted in coal combustion, and on the efficacy of various environmental control technologies for controlling airborne emissions. Bituminous and lignite coals have the highest mean arsenic concentrations, with subbituminous and anthracite coals having the lowest. However, all coal types show very significant variations in arsenic concentrations. Arsenic emissions from coal combustion are not well-characterized, particularly with regard to determination of specific arsenic compounds. Variations in emission, rates of more than an order of magnitude have been reported for some boiler types. Data on the capture of arsenic by environmental control technologies are available primarily for systems with cold electrostatic precipitators, where removals of approximately 50 to 98% have been reported. Limited data for wet flue-gas-desulfurization systems show widely varying removals of from 6 to 97%. On the other hand, waste incineration plants report removals in a narrow range of from 95 to 99%. This report briefly reviews several areas of research that may lead to improvements in arsenic control for existing flue-gas-cleanup technologies and summarizes the status of analytical techniques for measuring arsenic emissions from combustion sources.

  3. Arsenic in Ground-Water Resources of the United States

    USGS Publications Warehouse

    Welch, Alan H.; Watkins, Sharon A.; Helsel, Dennis R.; Focazio, Michael J.

    2000-01-01

    Arsenic is a naturally occurring element in rocks, soils, and the waters in contact with them. Recognized as a toxic element for centuries, arsenic today also is a human health concern because it can contribute to skin, bladder, and other cancers (National Research Council, 1999). Recently, the National Research Council (1999) recommended lowering the current maximum contaminant level (MCL) allowed for arsenic in drinking water of 50 ?g/L (micrograms per liter), citing risks for developing bladder and other cancers. The U.S. Environmental Protection Agency (USEPA) will propose a new, and likely lower, arsenic MCL during 2000 (U.S. Environmental Protection Agency, 2000). This fact sheet provides information on where and to what extent natural concentrations of arsenic in ground water exceed possible new standards. The U.S. Geological Survey (USGS) has collected and analyzed arsenic in potable (drinkable) water from 18,850 wells in 595 counties across the United States during the past two decades. These wells are used for irrigation, industrial purposes, and research, as well as for public and private water supply. Arsenic concentrations in samples from these wells are similar to those found in nearby public supplies (see Focazio and others, 1999). The large number of samples, broad geographic coverage, and consistency of methods produce a more accurate and detailed picture of arsenic concentrations than provided by any previous studies.

  4. Accumulation of arsenic in drinking water distribution systems.

    PubMed

    Lytle, Darren A; Sorg, Thomas J; Frietch, Christy

    2004-10-15

    The tendency for iron solid surfaces to adsorb arsenic is well-known and has become the basis for several drinking water treatment approaches that remove arsenic. It is reasonable to assume that iron-based solids, such as corrosion deposits present in drinking water distribution systems, have similar adsorptive properties and could therefore concentrate arsenic and potentially re-release it into the distribution system. The arsenic composition of solids collected from drinking water distribution systems (pipe sections and hydrant flush solids), where the waters had measurable amounts of arsenic in their treated water, were determined. The elemental composition and mineralogy of 67 solid samples collected from 15 drinking water utilities located in Ohio (7), Michigan (7), and Indiana (1) were also determined. The arsenic content of these solids ranged from 10 to 13 650 microg of As/g of solid (as high as 1.37 wt %), and the major element of most solids was iron. Significant amounts of arsenic were even found in solids from systems that were exposed to relatively low concentrations of arsenic (<10 microg/L) in the water.

  5. Radioactive decay.

    PubMed

    Groch, M W

    1998-01-01

    When a parent radionuclide decays to its daughter radionuclide by means of alpha, beta, or isomeric transition, the decay follows an exponential form, which is characterized by the decay constant lambda. The decay constant represents the probability per unit time that a single radioatom will decay. The decay equation can be used to provide a useful expression for radionuclide decay, the half-life, the time when 50% of the radioatoms present will have decayed. Radiotracer half-life has direct implications in nuclear imaging, radiation therapy, and radiation safety because radionuclide half-life affects the ability to evaluate tracer kinetics and create appropriate nuclear images and also affects organ, tumor, and whole-body radiation dose. The number of radioatoms present in a sample is equal to the activity, defined as the number of transitions per unit time, divided by the decay constant; the mass of radioatoms present in a sample can be calculated to determine the specific activity (activity per unit mass). The dynamic relationship between the number of parent and daughter atoms present over time may lead to radioactive equilibrium, which takes two forms--secular and transient--and has direct relevance to generator-produced radionuclides.

  6. Evidence for arsenic essentiality.

    PubMed

    Uthus, E O

    1992-06-01

    Although numerous studies with rats, hamsters, minipigs, goats and chicks have indicated that arsenic is an essential nutrient, the physiological role of arsenic is open to conjecture. Recent studies have suggested that arsenic has a physiological role that affects the formation of various metabolites of methionine metabolism including taurine and the polyamines. The concentration of plasma taurine is decreased in arsenic-deprived rats and hamsters. The hepatic concentration of polyamines and the specific activity of an enzyme necessary for the synthesis of spermidine and spermine, S-adenosylmethionine decarboxylase, are also decreased in arsenic-deprived rats. Thus, evidence has been obtained which indicates that arsenic is of physiological importance, especially when methionine metabolism is stressed (e.g. pregnancy, lactation, methionine deficiency, vitamin B6 deprivation). Any possible nutritional requirement by humans can be estimated only by using data from animal studies. The arsenic requirement for growing chicks and rats has been suggested to be near 25 ng g(-1) diet. Thus, a possible human requirement is 12 μg day(-1). The reported arsenic content of diets from various parts of the world indicates that the average intake of arsenic is in the range of 12-40 μg. Fish, grain and cereal products contribute most arsenic to the diet.

  7. Estimation of annual effective dose due to natural radioactive elements in ingestion of foodstuffs in tin mining area of Jos-Plateau, Nigeria.

    PubMed

    Jibiri, N N; Farai, I P; Alausa, S K

    2007-01-01

    Soils and food crops from a former tin mining location in a high background radiation area on the Jos-Plateau, Nigeria were collected and analyzed by gamma spectrometry to measure their contents of 40K, 238U and 232Th. As well as collecting samples, in situ dose rates on farms were measured using a precalibrated survey meter. Activity concentrations determined in food crops were compared with the local food derivatives or diets to investigate the possible removal or addition of radionuclides during food preparation by cooking or other means. Potassium-40 was found to contribute the highest activity in all the food products. The activity concentration of 40K, 238U and 232Th in local prepared diets ranged between 60 and 494 Bq kg-1, between BDL and 48 Bq kg-1 and between BDL and 17 Bq kg-1, respectively. The internal effective dose to individuals from the consumption of the food types was estimated on the basis of the measured radionuclide contents in the food crops. It ranged between 0.2 microSv y-1 (beans) and 2164 microSv y-1 (yam) while the annual external gamma effective dose in the farms due to soil radioactivity ranged between 228 microSv and 4065 microSv.

  8. Arsenic treatment considerations

    SciTech Connect

    Chen, H.W.; Frey, M.M.; Clifford, D.; McNeill, L.S.; Edwards, M.

    1999-03-01

    The best arsenic treatment technique for a given utility will depend on arsenic concentration and species in source water, other constituents in the water, existing treatment processes, treatment costs, and handling of residuals. To evaluate these issues, a national survey investigated arsenic occurrence and speciation in US drinking water sources. In general, total arsenic concentration was higher in groundwater than in surface water supplies. Particulate arsenic was more abundant than previously suspected, and more arsenate than arsenite was present. The cost of arsenic treatment increased in the following order: modified conventional treatment {much_lt} activated alumina or anion exchange < reverse osmosis. Nevertheless, the most cost-effective treatment still might not be best, because secondary treatment benefits and residuals handling should also be taken into account.

  9. Redox Cycling and Arsenic Transport to Groundwater in Bangladesh

    NASA Astrophysics Data System (ADS)

    Meilleur, D.; Martin, A. J.; Kotzer, T.; Hedberg, S.; Wepruk, R.; Beckie, R.; Polizzotto, M. L.; Harvey, C.; Fendorf, S.

    2004-12-01

    Arsenic is a contaminant in the groundwater of the Ganges delta. In Bangladesh alone, an estimated 57 million people may be drinking water with unsafe arsenic levels. The source of arsenic appears to be natural, solid-phase arsenic in the sediments, and various theories have been put forth regarding the modes of arsenic release to solution, ranging from oxidative or reductive degradation of arsenic-bearing solids to competitive ligand displacement by phosphate. Currently, reductive dissolution of Fe(III) (hydr)oxides and concomitant arsenic release is the most widely accepted explanation of the high arsenic concentrations in groundwater. However, much of the information about potential mechanisms of arsenic release has been gleaned solely from solution-phase data, and many puzzles linger concerning the distribution of arsenic. Only recently have studies been initiated that provide a comprehensive look at microbiology, hydrology, and chemistry of contaminated aquifers in Bangladesh. Using micro-X-ray fluorescence elemental mapping and micro-X-ray absorption near-edge structure spectroscopy, we have detected detrital arsenic-bearing sulfides in the aquifer sediments from our field site in Munshiganj, Bangladesh. The presence of detrital sulfides has been previously discounted, but their presence may, in fact, provide an important source of arsenic. Furthermore, their presence combined with a lack of ferric (hydr)oxides at depth is indicative of the reductive degradation of the latter phase. Rapid abiotic desorption of arsenic from sediments illustrates that a labile arsenic phase is easily transported through the aquifer sands. Addition of ferrihydrite, however, removes arsenic from solution and would minimize transport (a phenomenon not observed within the aquifers of Bangladesh). Based on our results, and in accordance with existing hydrological and biogeochemical data, reductive dissolution of ferric (hydr)oxides transpires in the surface and near

  10. Arsenic-Induced Pancreatitis

    PubMed Central

    Connelly, Sean; Zancosky, Krysia; Farah, Katie

    2011-01-01

    The introduction of all-trans retinoic acid (ATRA) and arsenic trioxide has brought about tremendous advancement in the treatment of acute promyelocytic myelogenous leukemia (APML). In most instances, the benefits of these treatments outweigh the risks associated with their respective safety profiles. Although acute pancreatitis is not commonly associated with arsenic toxicity, it should be considered as a possible side effect. We report a case of arsenic-induced pancreatitis in a patient with APML. PMID:22606427

  11. The global menace of arsenic and its conventional remediation - A critical review.

    PubMed

    Sarkar, Arpan; Paul, Biswajit

    2016-09-01

    Arsenic is a ubiquitous element found in the earth crust with a varying concentration in the earth soil and water. Arsenic has always been under the scanner due to its toxicity in human beings. Contamination of arsenic in drinking water, which generally finds its source from arsenic-containing aquifers; has severely threatened billions of people all over the world. Arsenic poisoning is worse in Bangladesh where As(III) is abundant in waters of tube wells. Natural occurrence of arsenic in groundwater could result from both, oxidative and reductive dissolution. Geothermally heated water has the potential to liberate arsenic from surrounding rocks. Inorganic arsenic has been found to have more toxicity than the organic forms of arsenic. MMA and DMA are now been considered as the organic arsenic compounds having the potential to impair DNA and that is why MMA and DMA are considered as carcinogens. Endless efforts of researchers have elucidated the source, behavior of arsenic in various parts of the environment, mechanism of toxicity and various remediation processes; although, there are lots of areas still to be addressed. In this article, attempts have been made to lay bare an overview of geochemistry, toxicity and current removal techniques of arsenic together. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Methods of analysis for toxic elements in food products. 1. Mineralization methods to determine heavy metals and arsenic according to the USSR standard

    SciTech Connect

    Skurikhin, I.M.

    1989-03-01

    Results of the work of 22 laboratories in the USSR on optimizing methods for mineralizing foods to determine Pb, Cd, As, Zn, Cu, Sn, and Fe are summarized. Recommendations are given on dry and wet mineralization as related to the analyte and the kind of food product. Optimum amounts of test portions for 22 food groups are also recommended according to the element of interest.

  13. Reactor radioactive emission monitor

    SciTech Connect

    Jester, W.A.; Mc Master, I.B.; Baratta, A.J.

    1987-05-05

    This patent describes a means for measuring quantities of a selected radioactive component in a stream of radioactive fluid. The means comprise: a first fluid path with a first means for retaining the selected radioactive component mounted in the fluid path for retaining the radioactive component while passing the remainder of the stream of radioactive fluid; a second fluid path with a second means for retaining the selected radioactive component mounted in the second fluid path for retaining the radioactive component while passing the remainder of the stream of the radioactive fluid; first and second detectors for detecting the level of radioactivity emitted by the retained radioactive component in the first and second retaining means; a means for integrating the output of one or more of the detectors as a function of time to measure any increase in the radioactivity emitted by the radioactive component retained by the retaining means, and the increase being representative of the amount of selected radioactive component present in the stream of radioactive fluid.

  14. Arsenic geochemistry in a biostimulated aquifer: an aqueous speciation study.

    PubMed

    Stucker, Valerie K; Williams, Kenneth H; Robbins, Mark J; Ranville, James F

    2013-06-01

    Stimulating microbial growth through the use of acetate injection wells at the former uranium mill site in Rifle, Colorado, USA, has been shown to decrease dissolved uranium (VI) concentrations through bacterial reduction to immobile uranium (IV). Bioreduction also changed the redox chemistry of site groundwater, altering the mobility of several other redox-sensitive elements present in the subsurface, including iron, sulfur, and arsenic. Following acetate amendment at the site, elevated concentrations of arsenic in the groundwater were observed. Ion chromatography-inductively coupled plasma-mass spectrometry was used to determine the aqueous arsenic speciation. Upgradient samples, unexposed to acetate, showed low levels of arsenic (≈1 μM), with greater than 90% as arsenate (As[V]) and a small amount of arsenite (As[III]). Downgradient acetate-stimulated water samples had much higher levels of arsenic (up to 8 μM), and 4 additional thioarsenic species were present under sulfate-reducing conditions. These thioarsenic species demonstrate a strong correlation between arsenic release and sulfide concentrations in groundwater, and their formation may explain the elevated total arsenic concentrations. An alternative remediation approach, enhanced flushing of uranium, was accomplished by addition of bicarbonate and did not result in highly elevated arsenic concentrations. Copyright © 2013 SETAC.

  15. Studying the effect of radioactive wastes at the Ak-Tyuz deposit on radionuclide and elemental composition of water objects of Kichi-Kemin River.

    PubMed

    Solodukhin, V; Poznyak, V

    2015-06-01

    This article reports on radionuclide and elemental composition studies of water and bottom sediment samples taken from Kichi-Kemin River in vicinity of the industrial area of the Ak-Tyuz thorium deposit in Kyrgyzstan near the border with Kazakhstan. The methods used included instrumental γ-spectrometry, neutron activation analysis, X-ray fluorescent analysis and inductively coupled plasma mass spectrometry. The obtained results demonstrated the pronounced negative anthropogenic impact of this area on the quality of water in the Kichi-Kemin River imposing radiological hazards on this tributary of the trans-boundary Shu River.

  16. How Certain Trace Elements Behave.

    ERIC Educational Resources Information Center

    Zingaro, Ralph A.

    1979-01-01

    Fluorine, selenium, tin, and arsenic are among the trace elements occurring in the environment which are considered. Emphasis is given to developing a qualitative survey of the extent and kinds of metal transformations and their resultant effects. (CS)

  17. How Certain Trace Elements Behave.

    ERIC Educational Resources Information Center

    Zingaro, Ralph A.

    1979-01-01

    Fluorine, selenium, tin, and arsenic are among the trace elements occurring in the environment which are considered. Emphasis is given to developing a qualitative survey of the extent and kinds of metal transformations and their resultant effects. (CS)

  18. Arsenic (+3 oxidation state) methyltransferase and the methylation of arsenicals in the invertebrate chordate Ciona intestinalis

    EPA Science Inventory

    The biotransformation of inorganic arsenic (iAs) involves methylation by an arsenic (+3 oxidation state) methyltransferase (AS3MT), yielding methyl arsenic (MA), dimethyl arsenic (DMA), and trimethylarsenic (TMA). To identify molecular mechanisms that coordinate arsenic biotra...

  19. Arsenic (+3 oxidation state) methyltransferase and the methylation of arsenicals in the invertebrate chordate Ciona intestinalis

    EPA Science Inventory

    The biotransformation of inorganic arsenic (iAs) involves methylation by an arsenic (+3 oxidation state) methyltransferase (AS3MT), yielding methyl arsenic (MA), dimethyl arsenic (DMA), and trimethylarsenic (TMA). To identify molecular mechanisms that coordinate arsenic biotra...

  20. Process for decontaminating radioactive liquids using a calcium cyanamide-containing composition. [Patent application

    DOEpatents

    Silver, G.L.

    1980-09-24

    The present invention provides a process for decontaminating a radioactive liquid containing a radioactive element capable of forming a hydroxide. This process includes the steps of contacting the radioactive liquid with a decontaminating composition and separating the resulting radioactive sludge from the resulting liquid. The decontaminating composition contains calcium cyanamide.

  1. RADIO-ACTIVE TRANSDUCER

    DOEpatents

    Wanetick, S.

    1962-03-01

    ABS>ure the change in velocity of a moving object. The transducer includes a radioactive source having a collimated beam of radioactive particles, a shield which can block the passage of the radioactive beam, and a scintillation detector to measure the number of radioactive particles in the beam which are not blocked by the shield. The shield is operatively placed across the radioactive beam so that any motion normal to the beam will cause the shield to move in the opposite direction thereby allowing more radioactive particles to reach the detector. The number of particles detected indicates the acceleration. (AEC)

  2. Arsenic exposure and DNA methylation among elderly men

    PubMed Central

    Lambrou, Angeliki; Baccarelli, Andrea; Wright, Robert O.; Weisskopf, Marc; Bollati, Valentina; Amarasiriwardena, Chitra; Vokonas, Pantel; Schwartz, Joel

    2012-01-01

    BACKGROUND Arsenic exposure has been linked to epigenetic modifications such as DNA methylation in in vitro and animal studies. This association has also been explored in highly exposed human populations, but studies among populations environmentally exposed to low arsenic levels are lacking. METHODS We evaluated the association between exposure to arsenic, measured in toenails, and blood DNA methylation in Alu and Long Interspersed Nucleotide Element-1 (LINE-1) repetitive elements in elderly men environmentally exposed to low levels of arsenic. We also explored potential effect modification by plasma folate, cobalamin (vitamin B12), and pyridoxine (vitamin B6). The study population was 581 participants from the Normative Aging Study in Boston, of whom 434, 140, and 7 had 1, 2, and 3 visits, respectively, between 1999-2002 and 2006-2007. We used mixed-effects models and included interaction terms to assess potential effect modification by nutritional factors. RESULTS There was a trend of increasing Alu and decreasing LINE-1 DNA methylation as arsenic exposure increased. In subjects with plasma folate below the median (< 14.1 ng/ml), arsenic was positively associated with Alu DNA methylation (β=0.08 [95% confidence interval = 0.03 to 0.13] for one interquartile range [0.06μg/g] increase in arsenic) while a negative association was observed in subjects with plasma folate above the median (β=-0.08 [-0.17 to 0.01]). CONCLUSIONS We found an association between arsenic exposure and DNA methylation in Alu repetitive elements that varied by folate level. This suggests a potential role for nutritional factors in arsenic toxicity. PMID:22833016

  3. Mechanisms of arsenic biotransformation.

    PubMed

    Vahter, Marie

    2002-12-27

    Inorganic arsenic, a documented human carcinogen, is methylated in the body by alternating reduction of pentavalent arsenic to trivalent and addition of a methyl group from S-adenosylmethionine. Glutathione, and possibly other thiols, serve as reducing agents. The liver is the most important site of arsenic methylation, but most organs show arsenic methylating activity. The end metabolites are methylarsonic acid (MMA) and dimethylarsinic acid (DMA). These are less reactive with tissue constituents than inorganic arsenic and readily excreted in the urine. However, reactive intermediates may be formed. Absorbed arsenate (As(V)) is fairly rapidly reduced in blood to As(III), which implies increased toxicity. Also, intermediate reduced forms of the methylated metabolites, MMA(III) and DMA(III), have been detected in human urine. In particular MMA(III) is highly toxic. To what extent MMA(III) and DMA(III) contribute to the observed toxicity following exposure to inorganic arsenic remains to be elucidated. There are marked differences in the metabolism of arsenic between mammalian species, population groups and individuals. There are indications that subjects with low MMA in urine have faster elimination of ingested arsenic, compared to those with more MMA in urine.

  4. Arsenic activation neutron detector

    DOEpatents

    Jacobs, Eddy L.

    1981-01-01

    A detector of bursts of neutrons from a deuterium-deuteron reaction includes a quantity of arsenic adjacent a gamma detector such as a scintillator and photomultiplier tube. The arsenic is activated by the 2.5 Mev neutrons to release gamma radiation which is detected to give a quantitative representation of detected neutrons.

  5. Arsenic activation neutron detector

    DOEpatents

    Jacobs, E.L.

    1980-01-28

    A detector of bursts of neutrons from a deuterium-deuteron reaction includes a quantity of arsenic adjacent a gamma detector such as a scintillator and photomultiplier tube. The arsenic is activated by the 2.5-MeV neutrons to release gamma radiation which is detected to give a quantitative representation of detected neutrons.

  6. An update on arsenic

    SciTech Connect

    Malachowski, M.E. )

    1990-09-01

    Arsenic poisoning is more than just a medical curiosity. Cases of acute and chronic intoxication continue to occur in the United States. Much is now known about the biochemical mechanisms of injury, which has led to a rational basis for therapy. Most importantly, however, the clinician must stay alert to correctly diagnose and treat cases of arsenic poisoning.23 references.

  7. [Acute arsenic poisoning].

    PubMed

    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.

  8. Contamination status of arsenic and other trace elements in drinking water and residents from Tarkwa, a historic mining township in Ghana.

    PubMed

    Asante, Kwadwo Ansong; Agusa, Tetsuro; Subramanian, Annamalai; Ansa-Asare, Osmund D; Biney, Charles A; Tanabe, Shinsuke

    2007-01-01

    This study was conducted to assess the contamination status of 22 trace elements, especially As in water and residents in Tarkwa, a historic mining town in Ghana. Drinking water and human urine samples were collected from Tarkwa in addition to control samples taken from Accra, the capital of Ghana in March, 2004. Concentrations of As and Mn in some drinking water samples from Tarkwa were found above the WHO drinking water guidelines posing a potential health risk for the people. A potential health risk of As and Mn is a concern for the people consuming the contaminated water in this area. No significant difference of As concentrations in human urine between mining town (Tarkwa) and control site (Accra) was observed. Although As concentrations in drinking water in Tarkwa were low, urinary As levels were comparable to those reported in highly As-affected areas in the world. These results suggest the presence of other sources of As contamination in Ghana. This is the first study on multi-elemental contamination in drinking water and human from a mining town in Ghana.

  9. Multi-trace element levels and arsenic speciation in urine of e-waste recycling workers from Agbogbloshie, Accra in Ghana.

    PubMed

    Asante, Kwadwo Ansong; Agusa, Tetsuro; Biney, Charles Augustus; Agyekum, William Atuobi; Bello, Mohammed; Otsuka, Masanari; Itai, Takaaki; Takahashi, Shin; Tanabe, Shinsuke

    2012-05-01

    To understand human contamination by multi-trace elements (TEs) in electrical and electronic waste (e-waste) recycling site at Agbogbloshie, Accra in Ghana, this study analyzed TEs and As speciation in urine of e-waste recycling workers. Concentrations of Fe, Sb, and Pb in urine of e-waste recycling workers were significantly higher than those of reference sites after consideration of interaction by age, indicating that the recycling workers are exposed to these TEs through the recycling activity. Urinary As concentration was relatively high, although the level in drinking water was quite low. Speciation analysis of As in human urine revealed that arsenobetaine and dimethylarsinic acid were the predominant As species and concentrations of both species were positively correlated with total As concentration as well as between each other. These results suggest that such compounds may be derived from the same source, probably fish and shellfish and greatly influence As exposure levels. To our knowledge, this is the first study on human contamination resulting from the primitive recycling of e-waste in Ghana. This study will contribute to the knowledge about human exposure to trace elements from an e-waste site in a less industrialized region so far scantly covered in the literature.

  10. Issues of natural radioactivity in phosphates

    SciTech Connect

    Schnug, E.; Haneklaus, S.; Schnier, C.; Scholten, L.C.

    1996-12-31

    The fertilization of phosphorus (P) fertilizers is essential in agricultural production, but phosphates contain in dependence on their origin different amounts of trace elements. The problem of cadmium (Cd) loads and other heavy metals is well known. However, only a limited number of investigations examined the contamination of phosphates with the two heaviest metals, uranium (U) and thorium (Th), which are radioactive. Also potassium (K) is lightly radioactive. Measurements are done n the radioactivity content of phosphates, P fertilizers and soils. The radiation doses to workers and public as well as possible contamination of soils from phosphate rock or fertilizer caused by these elements or their daughter products is of interest with regard to radiation protection. The use of P fertilizers is necessary for a sustainable agriculture, but it involves radioactive contamination of soils. The consequences of the use of P fertilizers is discussed, also with regard to existing and proposed legislation. 11 refs., 2 figs., 7 tabs.

  11. ELECTRONIC ANALOG COMPUTER FOR DETERMINING RADIOACTIVE DISINTEGRATION

    DOEpatents

    Robinson, H.P.

    1959-07-14

    A computer is presented for determining growth and decay curves for elements in a radioactive disintegration series wherein one unstable element decays to form a second unstable element or isotope, which in turn forms a third element, etc. The growth and decay curves of radioactive elements are simulated by the charge and discharge curves of a resistance-capacitance network. Several such networks having readily adjustable values are connected in series with an amplifier between each successive pair. The time constant of each of the various networks is set proportional to the half-life of a corresponding element in the series represented and the charge and discharge curves of each of the networks simulates the element growth and decay curve.

  12. Radioactive diagnostic agent

    SciTech Connect

    Shigematsu, A.; Aihara, M.; Matsuda, M.; Suzuki, A.; Tsuya, A.

    1984-02-07

    A radioactive diagnostic agent for renal cortex, adrenal cortex, myocardium, brain stem, spinal nerve, etc., which comprises as an essential component monoiodoacetic acid wherein the iodine atom is radioactive.

  13. Isotopic evidence for a link between agricultural irrigation and high arsenic concentrations in groundwater

    NASA Astrophysics Data System (ADS)

    Li, M.; Wang, Y.; Shock, E.

    2011-12-01

    An isotope-based survey was carried out in the Datong Basin, northern China to investigate the hydrogeology of groundwater with high arsenic concentrations. Oxygen isotope (δ18O), hydrogen isotope (δD) and radioactive hydrogen isotope (3H) measurements were conducted with the aim of characterizing the groundwater origins and flow dynamics in this arsenic-contaminated groundwater system. Groundwater dating results from 3H measurements show that groundwaters from 20m ~ 70m have a wide range of ages (10a~ 191a), indicating diverse groundwater sources. In contrast, deeper groundwaters (70m ~90m) display a narrower age range (35a ~ 47a). In addition, the shallow-aquifer (<70m), groundwaters exhibit wide variations in δ18O and δD, from -12.7% to -6.96% and -97.1% to -49.8%, respectively. Deep groundwaters (>70m) possess relatively narrower isotopic ranges and mostly lighter isotopic ratios, from -12.8% to -8.88% and -97.6% to -71.7%, respectively. Comparison with the local meteoric water line shows that groundwater δ18O and δD values plot with a shallower slope, consistent with the arid-semiarid climate of the Datong Basin, as well as a meteoric origin of the groundwater, and points to precipitation as the dominant source of recharge to the deeper aquifers in the study area. Groundwaters with high arsenic concentrations (100μg/L ~ 309μg/L) mainly occur in aquifers at depths between 20m and 70m, while shallower (<20m) and deeper (>70m) groundwaters carry relatively lower arsenic concentrations (<50μg/L). This result differs from previous studies[1] [2], which documented that groundwaters with high arsenic concentrations occur primarily in the upper aquifers (<50m). It is striking that the groundwaters with elevated arsenic concentrations are also those with the greatest diversity of tritium ages and dispersion of δ18O and δD values, suggesting that a single process may explain all three data sets. One explanation is that extensive irrigation with groundwaters

  14. A laboratory activity for teaching natural radioactivity

    NASA Astrophysics Data System (ADS)

    Pilakouta, M.; Savidou, A.; Vasileiadou, S.

    2017-01-01

    This paper presents an educational approach for teaching natural radioactivity using commercial granite samples. A laboratory activity focusing on the topic of natural radioactivity is designed to develop the knowledge and understanding of undergraduate university students on the topic of radioactivity, to appreciate the importance of environmental radioactivity and familiarize them with the basic technology used in radioactivity measurements. The laboratory activity is divided into three parts: (i) measurements of the count rate with a Geiger-Muller counter of some granite samples and the ambient background radiation rate, (ii) measurement of one of the samples using gamma ray spectrometry with a NaI detector and identification of the radioactive elements of the sample, (iii) using already recorded 24 h gamma ray spectra of the samples from the first part (from the Granite Gamma-Ray Spectrum Library (GGRSL) of our laboratory) and analyzing selected peaks in the spectrum, students estimate the contribution of each radioactive element to the total specific activity of each sample. A brief description of the activity as well as some results and their interpretation are presented.

  15. Environmental Assessment for Kirtland Air Force Base Arsenic Compliance System

    DTIC Science & Technology

    2003-09-01

    have migrated from the area (Between Nov. 1-Feb. 28). Implementation of these burrowing owl avoidance measures would prevent any long-term impacts to...FINAL ENVIRONMENTAL ASSESSMENT FOR KIRTLAND AIR FORCE BASE ARSENIC COMPLIANCE SYSTEM September 2003 Prepared for 377th Air Base Wing Air...Kirtland Air Force Base Arsenic Compliance System 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e

  16. Environmental biochemistry of arsenic.

    PubMed

    Tamaki, S; Frankenberger, W T

    1992-01-01

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

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

    PubMed Central

    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

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

    PubMed Central

    Roberge, Jason; O’Rourke, Mary Kay; Meza-Montenegro, Maria Mercedes; Gutiérrez-Millán, Luis Enrique; Burgess, Jefferey L.; Harris, Robin B.

    2012-01-01

    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. PMID:22690182

  19. Binational arsenic exposure survey: methodology and estimated arsenic intake from drinking water and urinary arsenic concentrations.

    PubMed

    Roberge, Jason; O'Rourke, Mary Kay; Meza-Montenegro, Maria Mercedes; Gutiérrez-Millán, Luis Enrique; Burgess, Jefferey L; Harris, Robin B

    2012-04-01

    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.

  20. Effects of soil composition and mineralogy on the bioaccessibility of arsenic from tailings and soil in gold mine districts of Nova Scotia.

    PubMed

    Meunier, Louise; Walker, Stephen R; Wragg, Joanna; Parsons, Michael B; Koch, Iris; Jamieson, Heather E; Reimer, Kenneth J

    2010-04-01

    Bioaccessibility tests and mineralogical analyses were performed on arsenic-contaminated tailings and soils from gold mine districts of Nova Scotia, Canada, to examine the links between soil composition, mineralogy, and arsenic bioaccessibility. Arsenic bioaccessibility ranges from 0.1% to 49%. A weak correlation was observed between total and bioaccessible arsenic concentrations, and the arsenic bioaccessibility was not correlated with other elements. Bulk X-ray absorption near-edge structure analysis shows arsenic in these near-surface samples is mainly in the pentavalent form, indicating that most of the arsenopyrite (As(1-)) originally present in the tailings and soils has been oxidized during weathering reactions. Detailed mineralogical analyses of individual samples have identified up to seven arsenic species, the relative proportions of which appear to affect arsenic bioaccessibility. The highest arsenic bioaccessibility (up to 49%) is associated with the presence of calcium-iron arsenate. Samples containing arsenic predominantly as arsenopyrite or scorodite have the lowest bioaccessibility (<1%). Other arsenic species identified (predominantly amorphous iron arsenates and arsenic-bearing iron(oxy)hydroxides) are associated with intermediate bioaccessibility (1 to 10%). The presence of a more soluble arsenic phase, even at low concentrations, results in increased arsenic bioaccessibility from the mixed arsenic phases associated with tailings and mine-impacted soils.

  1. Effects of Soil Composition and Mineralogy on the Bioaccessibility of Arsenic from Tailings and Soil in Gold Mine Districts of Nova Scotia

    SciTech Connect

    Meunier, Louise; Walker, Stephen R.; Wragg, Joanna; Parsons, Michael B.; Koch, Iris; Jamieson, Heather E.; Reimer, Kenneth J.

    2010-10-20

    Bioaccessibility tests and mineralogical analyses were performed on arsenic-contaminated tailings and soils from gold mine districts of Nova Scotia, Canada, to examine the links between soil composition, mineralogy, and arsenic bioaccessibility. Arsenic bioaccessibility ranges from 0.1% to 49%. A weak correlation was observed between total and bioaccessible arsenic concentrations, and the arsenic bioaccessibility was not correlated with other elements. Bulk X-ray absorption near-edge structure analysis shows arsenic in these near-surface samples is mainly in the pentavalent form, indicating that most of the arsenopyrite (As{sup 1-}) originally present in the tailings and soils has been oxidized during weathering reactions. Detailed mineralogical analyses of individual samples have identified up to seven arsenic species, the relative proportions of which appear to affect arsenic bioaccessibility. The highest arsenic bioaccessibility (up to 49%) is associated with the presence of calcium-iron arsenate. Samples containing arsenic predominantly as arsenopyrite or scorodite have the lowest bioaccessibility (<1%). Other arsenic species identified (predominantly amorphous iron arsenates and arsenic-bearing iron(oxy)hydroxides) are associated with intermediate bioaccessibility (1 to 10%). The presence of a more soluble arsenic phase, even at low concentrations, results in increased arsenic bioaccessibility from the mixed arsenic phases associated with tailings and mine-impacted soils.

  2. Arsenic, Anaerobes, and Autotrophy.

    NASA Astrophysics Data System (ADS)

    Oremland, R. S.

    2008-12-01

    That microbes have resistance to the toxic arsenic oxyanions arsenite [As(III)] and arsenate [As(V)] has been recognized for some time. More recently it was shown that certain prokaryotes can demonstrate As- dependent growth by conserving the energy gained from the aerobic oxidation of As(III) to As(V), or from the reduction of As(V) to As(III) under anaerobic conditions. During the course of our field studies of two alkaline, hypersaline soda lakes (Mono Lake and Searles Lake, CA) we have discovered several new anaerobic chemo- and photo-autotrophic bacteria that can center their energy gain around the redox reactions between As(III) and As(V). Alkalilimnicola ehrlichii, isolated from the water column of Mono Lake is a nitrate-respiring, As(III)-oxidizing chemoautotroph of the gamma-proteobacteria that has a highly flexible metabolism. It can function either as a facultative anaerobe or as a chemo-autotroph, or as a heterotroph (Hoeft et al., 2007). In contrast, strain MLMS-1 of the delta-proteobacteria was also isolated from Mono Lake, but to date is the first example of an obligate As(V)-respirer that is also an obligate chemo-autotroph, gaining its energy via the oxidation of sulfide to sulfate (Hoeft et al., 2004). Strain SLAS-1, isolated from salt-saturated Searles Lake is a member of the Halananerobiales, and can either grow as a heterotroph (lactate e-donor) or chemo- autotroph (sulfide e-donor) while respiring As(V). The fact that it can achieve this feat at salt-saturation (~ 340 g/L) makes it a true extremophile (Oremland et. al., 2005). Finally, strain PHS-1 isolated from a hot spring on Paoha island in Mono Lake is the first example of a photosynthetic bacterium of the gamma- proteobacteria able to link its growth to As(III)-dependent anoxygenic photosynthesis (Kulp et al., 2008). These novel microbes give us new insights into the evolution of arsenic-based metabolism and their role in the biogeochemical cycling of this toxic element. Hoeft, S.E., et

  3. A survey of arsenic, manganese, boron, thorium, and other toxic metals in the groundwater of a West Bengal, India neighbourhood.

    PubMed

    Bacquart, Thomas; Bradshaw, Kelly; Frisbie, Seth; Mitchell, Erika; Springston, George; Defelice, Jeffrey; Dustin, Hannah; Sarkar, Bibudhendra

    2012-07-01

    Around 150 million people are at risk from arsenic-contaminated groundwater in India and Bangladesh. Multiple metal analysis in Bangladesh has found other toxic elements above the World Health Organization (WHO) health-based drinking water guidelines which significantly increases the number of people at risk due to drinking groundwater. In this study, drinking water samples from the Bongaon area (North 24 Parganas district, West Bengal, India) were analyzed for multiple metal contamination in order to evaluate groundwater quality on the neighbourhood scale. Each sample was analyzed for arsenic (As), boron (B), barium (Ba), chromium (Cr), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), and uranium (U). Arsenic was found above the WHO health-based drinking water guideline in 50% of these tubewells. Mn and B were found at significant concentrations in 19% and 6% of these tubewells, respectively. The maps of As, Mn, and B concentrations suggest that approximately 75% of this area has no safe tubewells. The concentrations of As, Mn, B, and many other toxic elements are independent of each other. The concentrations of Pb and U were not found above WHO health-based drinking water guidelines but they were statistically related to each other (p-value = 0.001). An analysis of selected isotopes in the Uranium, Actinium, and Thorium Radioactive Decay Series revealed the presence of thorium (Th) in 31% of these tubewells. This discovery of Th, which does not have a WHO health-based drinking water guideline, is a potential public health challenge. In sum, the widespread presence and independent distribution of other metals besides As must be taken into consideration for drinking water remediation strategies involving well switching or home-scale water treatment.

  4. Environmental biochemistry of arsenic

    SciTech Connect

    Tamaki, S.; Frankenberger, W.T. Jr. )

    1992-01-01

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

  5. Radioactivity level and toxic elemental concentration in groundwater at Dei-Dei and Kubwa areas of Abuja, north-central Nigeria

    NASA Astrophysics Data System (ADS)

    Maxwell, O.; Wagiran, H.; Lee, S. K.; Embong, Z.; Ugwuoke, P. E.

    2015-02-01

    The activity concentrations of uranium and toxic elements in Dei-Dei borehole, Kubwa borehole, Water Board and hand-dug well water samples in Abuja area were measured using inductively coupled plasma mass spectrometry (ICP-MS) system. The results obtained were used to calculate human radiological risk over lifetime consumption by the inhabitants in the area. The activity concentrations of 238U in all the water supplies for drinking ranges from 0.849 mBq L-1 to 2.699 mBq L-1 with the highest value of 2.699 mBq L-1 noted at Dei-Dei borehole whereas the lowest value of 0.849 mBq L-1 was noted in Kubwa borehole. The highest annual effective dose from natural 238U in all the water samples was found in Dei-Dei borehole with a value of 8.9×10-5 mSv y-1 whereas the lowest value was noted in Kubwa borehole with a value of 2.8×10-5 mSv y-1. The radiological risks for cancer mortality were found distinctly low, with the highest value of 1.01×10-7 reported at Dei-Dei borehole compared to Kubwa borehole with a value of 3.01×10-8. The cancer morbidity risk was noted higher in Dei-Dei borehole with a value of 1.55×10-7 whereas lower value of 4.88×10-9 was reported in Kubwa borehole. The chemical toxicity risk of 238U in drinking water over a lifetime consumption has a value of 0.006 μg kg-1 day-1 in Dei-Dei borehole whereas lower value of 0.002 μg kg-1 day-1 was found in Kubwa borehole. Measured lead (Pb) and chromium (Cr) concentrations reported higher in Water Board compared to Dei-Dei and Kubwa borehole samples. Significantly, this study inferred that the 238U concentrations originate from granitic strata of the tectonic events in the area; thus, there was a trend of diffusion towards north to south and re-deposition towards Dei-Dei area.

  6. Chronic exposure to arsenic, LINE-1 hypomethylation, and blood pressure: a cross-sectional study in Bangladesh.

    PubMed

    Hossain, Khaled; Suzuki, Takehiro; Hasibuzzaman, M M; Islam, Md Shofikul; Rahman, Atiqur; Paul, Sudip Kumar; Tanu, Tanzina; Hossain, Shakhawoat; Saud, Zahangir Alam; Rahman, Mashiur; Nikkon, Farjana; Miyataka, Hideki; Himeno, Seiichiro; Nohara, Keiko

    2017-03-07

    Chronic exposure to arsenic is associated with cancer and hypertension. Growing evidence suggests that altered methylation in long interspersed nuclear element-1 (LINE-1) is involved in many types of disorders, including cardiovascular disease. Here we evaluated the association between arsenic exposure and LINE-1 methylation levels, especially in relation to blood pressure (BP). A total of 236 subjects (175 from arsenic-endemic areas and 61 from a non-endemic area) in rural Bangladesh were recruited. The subjects' arsenic exposure levels (i.e., drinking water, hair and nail arsenic concentrations) were measured by inductively coupled plasma mass spectroscopy. The subjects' LINE-1 methylation levels were determined by pyrosequencing. The average LINE-1 methylation levels of the subjects living in the arsenic-endemic areas were significantly (p < 0.01) lower than those of the subjects living in the non-endemic area. In a sex-stratified analysis, the arsenic exposure levels in female but not male subjects showed a significant inverse association with LINE-1 methylation levels before (water arsenic: p < 0.01, hair arsenic: p < 0.05, nail arsenic: p < 0.001) and after (water arsenic: p < 0.01, hair arsenic: p < 0.05, nail arsenic: p < 0.001) adjustment for age, body mass index and smoking. Analyses examining interactions among arsenic levels, BP and LINE-1 methylation showed that arsenic-related elevated levels of BP were associated with LINE-1 hypomethylation. Our findings demonstrated that chronic exposure to arsenic was inversely associated with LINE-1 methylation levels in blood leukocyte DNA and this was more pronounced in females than males; in addition, the decreased levels of LINE-1 methylation might be involved in the arsenic-induced elevation of BP.

  7. Radioactivity and uranium content of some Cretaceous shales, central Great Plains

    USGS Publications Warehouse

    Tourtelot, Harry A.

    1955-01-01

    The Sharon Springs member of the Pierre shale of Cretaceous age, a hard black organic-rich shale similar to the Chattanooga shale, is radioactive throughout central and western South Dakota, most of Nebraska, northern Kansas, and northeastern Colorado. In the Missouri River valley, thin beds of the shale contain as much as 0.01 percent uranium. Beds as much as 20 feet thick or more have a radioactivity of about 0.01 percent equivalent uranium in southwestern Nebraska according to interpretation of gamma-ray well logs. The radioactivity and uranium content is highest in the Missouri River valley in South Dakota and in southwestern Nebraska where the shale rests disconformably on the underlying Niobrara formation of Cretaceous age. Near the Black Hills, and in the area to the north, the shale of the Sharon Springs member rests on a wedge of the Gammon ferruginous member of the Pierre, which is represented by a disonformity to the east and south, and the radioactivity of the shale is low although greater than that of over-lying strata. The shale also contains a suite of trace elements in which arsenic, boron, chromium, copper, molybdenum, nickel, selenium, and vanadium are conspicuous. Molybdenum and tin are less abundant in the Sharon Springs than in similar shales of Palezoic age and silver and selenium are more abundant. In the Great Plains region, the upper 30-50 feet of Cretaceous shales overlain unconformably by the White River group of Oligocene age has been altered to bright-colored material. This altered zone is chiefly the result of pre-Oligocene weathering although post-Oligocene ground water conditions also have affected the zone. The greatest radioactivity occurs in masses of unaltered shale measuring about 1 x 4 feet in cross section included in the lower part of the altered zone. Where the zone is developed on shale and marl of the Niobrara formation, parts of the included unaltered shale contains as much as 0.1 percent equivalent uranium and 0

  8. Size-dependent characterisation of historical gold mine wastes to examine human pathways of exposure to arsenic and other potentially toxic elements.

    PubMed

    Martin, Rachael; Dowling, Kim; Pearce, Dora C; Florentine, Singarayer; Bennett, John W; Stopic, Attila

    2016-10-01

    Abandoned historical gold mining wastes often exist as geographically extensive, unremediated, and poorly contained deposits that contain elevated levels of As and other potentially toxic elements (PTEs). One of the key variables governing human exposure to PTEs in mine waste is particle size. By applying a size-resolved approach to mine waste characterisation, this study reports on the proportions of mine waste relevant to human exposure and mobility, as well as their corresponding PTE concentrations, in four distinct historical mine wastes from the gold province in Central Victoria, Australia. To the best of our knowledge, such a detailed investigation and comparison of historical mining wastes has not been conducted in this mining-affected region. Mass distribution analysis revealed notable proportions of waste material in the readily ingestible size fraction (≤250 µm; 36.1-75.6 %) and the dust size fraction (≤100 µm; 5.9-45.6 %), suggesting a high potential for human exposure and dust mobilisation. Common to all mine waste types were statistically significant inverse trends between particle size and levels of As and Zn. Enrichment of As in the finest investigated size fraction (≤53 µm) is of particular concern as these particles are highly susceptible to long-distance atmospheric transport. Human populations that reside in the prevailing wind direction from a mine waste deposit may be at risk of As exposure via inhalation and/or ingestion pathways. Enrichment of PTEs in the finer size fractions indicates that human health risk assessments based on bulk contaminant concentrations may underestimate potential exposure intensities.

  9. Chronic Arsenic poisoning.

    PubMed

    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.

  10. Water hyacinth removes arsenic from arsenic-contaminated drinking water.

    PubMed

    Misbahuddin, Mir; Fariduddin, Atm

    2002-01-01

    Water hyacinth (Eichhornia crassipes) removes arsenic from arsenic-contaminated drinking water. This effect depends on several factors, such as the amount of water hyacinth, amount of arsenic present in the water, duration of exposure, and presence of sunlight and air. On the basis of the present study, the authors suggest that water hyacinth is useful for making arsenic-contaminated drinking water totally arsenic free. Water hyacinth provides a natural means of removing arsenic from drinking water at the household level without monetary cost.

  11. Arsenic removal during precipitative softening

    SciTech Connect

    McNeill, L.S.; Edwards, M.

    1997-05-01

    Because utilities with hard waters tend to have higher concentrations of arsenic, removal of arsenic via precipitative softening processes was investigated in the context of the more stringent proposed arsenic regulation. Arsenic removal can be facilitated by a variety of solids formed during softening including CaCO{sub 3}, Mg(OH){sub 2}, Mn(OH){sub 2}, and Fe(OH){sub 3}. The extent of As(V) removal is decreased in the presence of orthophosphate and carbonate. As(III) removal is much lower than As(V) removal. At typical solids concentrations, arsenic removal followed a linear isotherm for CaCO{sub 3}, Mg(OH){sub 2}, and Fe(OH){sub 3}, with constant percentage arsenic removal regardless of initial arsenic concentrations. However, for Mn(OH){sub 2} solids arsenic removal was sensitive to arsenic concentrations. A framework for predicting arsenate removal when multiple solids form during softening is presented.

  12. Bioaccessibility of lead and arsenic in traditional Indian medicines

    PubMed Central

    Koch, Iris; Moriarty, Maeve; House, Kim; Sui, Jie; Cullen, William R.; Saper, Robert B.; Reimer, Kenneth J.

    2011-01-01

    Arsenic and lead have been found in a number of traditional Ayurvedic medicines, and the practice of Rasa Shastra (combining herbs with metals, minerals and gems), or plant ingredients that contain these elements, may be possible sources. To obtain an estimate of arsenic and lead solubility in the human gastrointestinal tract, bioaccessibility of the two elements was measured in 42 medicines, using a physiologically-based extraction test. The test consisted of a gastric phase at pH 1.8 containing organic acids, pepsin and salt, followed by an intestinal phase, at pH 7 and containing bile and pancreatin. Arsenic speciation was measured in a subset of samples that had sufficiently high arsenic concentrations for the X-ray absorption near edge structure analysis used. Bioaccessible lead was found in 76% of samples, with a large range of bioaccessibility results, but only 29% of samples had bioaccessible arsenic. Lead bioaccessibility was high (close to 100%) in a medicine (Mahayograj Guggulu) that had been compounded with bhasmas (calcined minerals), including naga (lead) bhasma. For the samples in which arsenic speciation was measured, bioaccessible arsenic was correlated with the sum of As(V)–O and As(III)–O and negatively correlated with As–S. These results suggest that the bioaccessible species in the samples had been oxidized from assumed As–S raw medicinal ingredients (realgar, As4S4, added to naga (lead) bhasma and As(III)–S species in plants). Consumption at recommended doses of all medicines with bioaccessibile lead or arsenic would lead to the exceedance of at least one standard for acceptable daily intake of toxic elements. PMID:21864885

  13. Bioaccessibility of lead and arsenic in traditional Indian medicines.

    PubMed

    Koch, Iris; Moriarty, Maeve; House, Kim; Sui, Jie; Cullen, William R; Saper, Robert B; Reimer, Kenneth J

    2011-10-01

    Arsenic and lead have been found in a number of traditional Ayurvedic medicines, and the practice of Rasa Shastra (combining herbs with metals, minerals and gems), or plant ingredients that contain these elements, may be possible sources. To obtain an estimate of arsenic and lead solubility in the human gastrointestinal tract, bioaccessibility of the two elements was measured in 42 medicines, using a physiologically-based extraction test. The test consisted of a gastric phase at pH 1.8 containing organic acids, pepsin and salt, followed by an intestinal phase, at pH 7 and containing bile and pancreatin. Arsenic speciation was measured in a subset of samples that had sufficiently high arsenic concentrations for the X-ray absorption near edge structure analysis used. Bioaccessible lead was found in 76% of samples, with a large range of bioaccessibility results, but only 29% of samples had bioaccessible arsenic. Lead bioaccessibility was high (close to 100%) in a medicine (Mahayograj Guggulu) that had been compounded with bhasmas (calcined minerals), including naga (lead) bhasma. For the samples in which arsenic speciation was measured, bioaccessible arsenic was correlated with the sum of As(V)-O and As(III)-O and negatively correlated with As-S. These results suggest that the bioaccessible species in the samples had been oxidized from assumed As-S raw medicinal ingredients (realgar, As(4)S(4), added to naga (lead) bhasma and As(III)-S species in plants). Consumption at recommended doses of all medicines with bioaccessibile lead or arsenic would lead to the exceedance of at least one standard for acceptable daily intake of toxic elements. Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.

  14. A survey of arsenic in foodstuffs on sale in the United Kingdom and imported from Bangladesh.

    PubMed

    Al Rmalli, S W; Haris, P I; Harrington, C F; Ayub, M

    2005-01-20

    Arsenic is a highly toxic element and its presence in food composites is a matter of concern to the well being of both humans and animals. Arsenic-contaminated groundwater is often used in Bangladesh and West Bengal (India) to irrigate crops used for food and animal consumption, which could potentially lead to arsenic entering the human food chain. In this study, we used graphite furnace atomic absorption spectroscopy to determine the total arsenic concentrations in a range of foodstuffs, including vegetables, rice and fish, imported into the United Kingdom from Bangladesh. The mean and range of the total arsenic concentration in all the vegetables imported from Bangladesh were 54.5 and 5-540 microg/kg, respectively. The highest arsenic values found were for the skin of Arum tuber, 540 microg/kg, followed by Arum Stem, 168 microg/kg, and Amaranthus, 160 microg/kg. Among the other samples, freshwater fish contained total arsenic levels between 97 and 1318 microg/kg. The arsenic content of the vegetables from the UK was approximately 2- to 3-fold lower than those observed for the vegetables imported from Bangladesh. The levels of arsenic found in vegetables imported from Bangladesh in this study, in some cases, are similar to those previously recorded for vegetables grown in arsenic-affected areas of West Bengal, India, although lower than the levels reported in studies from Bangladesh. While the total arsenic content detected in our study in vegetables, imported from Bangladesh, is far less than the recommended maximum permitted level of arsenic, it does provide an additional source of arsenic in the diet. This raises the possibility that the level of arsenic intake by certain sectors of the UK population may be significantly higher then the general population and requires further investigations.

  15. Barium inhibits arsenic-mediated apoptotic cell death in human squamous cell carcinoma cells.

    PubMed

    Yajima, Ichiro; Uemura, Noriyuki; Nizam, Saika; Khalequzzaman, Md; Thang, Nguyen D; Kumasaka, Mayuko Y; Akhand, Anwarul A; Shekhar, Hossain U; Nakajima, Tamie; Kato, Masashi

    2012-06-01

    Our fieldwork showed more than 1 μM (145.1 μg/L) barium in about 3 μM (210.7 μg/L) arsenic-polluted drinking well water (n = 72) in cancer-prone areas in Bangladesh, while the mean concentrations of nine other elements in the water were less than 3 μg/L. The types of cancer include squamous cell carcinomas (SCC). We hypothesized that barium modulates arsenic-mediated biological effects, and we examined the effect of barium (1 μM) on arsenic (3 μM)-mediated apoptotic cell death of human HSC-5 and A431 SCC cells in vitro. Arsenic promoted SCC apoptosis with increased reactive oxygen species (ROS) production and JNK1/2 and caspase-3 activation (apoptotic pathway). In contrast, arsenic also inhibited SCC apoptosis with increased NF-κB activity and X-linked inhibitor of apoptosis protein (XIAP) expression level and decreased JNK activity (antiapoptotic pathway). These results suggest that arsenic bidirectionally promotes apoptotic and antiapoptotic pathways in SCC cells. Interestingly, barium in the presence of arsenic increased NF-κB activity and XIAP expression and decreased JNK activity without affecting ROS production, resulting in the inhibition of the arsenic-mediated apoptotic pathway. Since the anticancer effect of arsenic is mainly dependent on cancer apoptosis, barium-mediated inhibition of arsenic-induced apoptosis may promote progression of SCC in patients in Bangladesh who keep drinking barium and arsenic-polluted water after the development of cancer. Thus, we newly showed that barium in the presence of arsenic might inhibit arsenic-mediated cancer apoptosis with the modulation of the balance between arsenic-mediated promotive and suppressive apoptotic pathways.

  16. Chromated Arsenicals (CCA)

    EPA Pesticide Factsheets

    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.

  17. ARSENIC TREATMENT TECHNOLOGIES 1

    EPA Science Inventory

    A 75 minute presentation will be given at the State of Pennsylvania drinking water training session for state personnel. It will cover four topics: arsenic chemistry, best available technology, demonstration programs and technologies (adsorptive media and iron removal processes)....

  18. ENZYMOLOGY OF ARSENIC METHYLATION

    EPA Science Inventory

    Enzymology of Arsenic Methylation

    David J. Thomas, Pharmacokinetics Branch, Experimental Toxicology Division, National
    Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park...

  19. ENZYMOLOGY OF ARSENIC METHYLATION

    EPA Science Inventory

    Enzymology of Arsenic Methylation

    David J. Thomas, Pharmacokinetics Branch, Experimental Toxicology Division, National
    Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park...

  20. Determination of Arsenic in Sinus Wash and Tap Water by Inductively Coupled Plasma-Mass Spectrometry

    ERIC Educational Resources Information Center

    Donnell, Anna M.; Nahan, Keaton; Holloway, Dawone; Vonderheide, Anne P.

    2016-01-01

    Arsenic is a toxic element to which humans are primarily exposed through food and water; it occurs as a result of human activities and naturally from the earth's crust. An experiment was developed for a senior level analytical laboratory utilizing an Inductively Coupled Plasma-Mass Spectrometer (ICP-MS) for the analysis of arsenic in household…

  1. Determination of Arsenic in Sinus Wash and Tap Water by Inductively Coupled Plasma-Mass Spectrometry

    ERIC Educational Resources Information Center

    Donnell, Anna M.; Nahan, Keaton; Holloway, Dawone; Vonderheide, Anne P.

    2016-01-01

    Arsenic is a toxic element to which humans are primarily exposed through food and water; it occurs as a result of human activities and naturally from the earth's crust. An experiment was developed for a senior level analytical laboratory utilizing an Inductively Coupled Plasma-Mass Spectrometer (ICP-MS) for the analysis of arsenic in household…

  2. Arsenic-Containing Phosphatidylcholines: A New Group of Arsenolipids Discovered in Herring Caviar.

    PubMed

    Viczek, Sandra A; Jensen, Kenneth B; Francesconi, Kevin A

    2016-04-18

    A new group of arsenolipids based on cell-membrane phosphatidylcholines has been discovered in herring caviar (fish roe). A combination of HPLC with elemental and molecular mass spectrometry was used to identify five arsenic-containing phosphatidylcholines; the same technique applied to salmon caviar identified an arsenic-containing phosphatidylethanolamine. The arsenic group in these membrane lipids might impart particular properties to the molecules not displayed by their non-arsenic analogues. Additionally, the new compounds have human health implications according to recent results showing high cytotoxicity for some arsenolipids. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Urinary arsenic levels influenced by abandoned mine tailings in the Southernmost Baja California Peninsula, Mexico.

    PubMed

    Colín-Torres, Carlos G; Murillo-Jiménez, Janette M; Del Razo, Luz M; Sánchez-Peña, Luz C; Becerra-Rueda, Oscar F; Marmolejo-Rodríguez, Ana J

    2014-10-01

    Gold has been mined at San Antonio-El Triunfo, (Baja California Sur, Mexico) since the 18th century. This area has approximately 5,700 inhabitants living in the San Juan de Los Planes and El Carrizal hydrographic basins, close to more than 100 abandoned mining sites containing tailings contaminated with potentially toxic elements such as arsenic. To evaluate the arsenic exposure of humans living in the surrounding areas, urinary arsenic species, such as inorganic arsenic (iAs) and the metabolites mono-methylated (MMA) and di-methylated arsenic acids (DMA), were evaluated in 275 residents (18-84 years of age). Arsenic species in urine were analyzed by hydride generation-cryotrapping-atomic absorption spectrometry, which excludes the non-toxic forms of arsenic such as those found in seafood. Urinary samples contained a total arsenic concentration (sum of arsenical species) which ranged from 1.3 to 398.7 ng mL(-1), indicating 33% of the inhabitants exceeded the biological exposition index (BEI = 35 ng mL(-1)), the permissible limit for occupational exposure. The mean relative urinary arsenic species were 9, 11 and 80% for iAs, MMA and DMA, respectively, in the Los Planes basin, and 17, 10 and 73%, respectively, in the El Carrizal basin. These data indicated that environmental intervention is required to address potential health issues in this area.

  4. Crop Uptake of Arsenic from Flooded Paddy Fields in the Mekong Delta

    NASA Astrophysics Data System (ADS)

    Mohr, K.; Boye, K.

    2014-12-01

    Arsenic is found naturally in the soils in the Mekong delta in Vietnam and Cambodia. It originates from erosion in the Himalayas. When similar levels of arsenic are present in well aerated soil, it is not dangerous, because it is strongly bound to soil particles and not readily plant available. Arsenic is released when the soil is saturated with water, and therefore contaminates crops grown in flooded fields. This results in people being exposed to unsafe levels of arsenic from their food, such as rice and lotus, which are normally grown under flooded conditions. Rice is a staple food in these regions, so the transfer of arsenic from soil, to water, and ultimately into the grain, poses a threat to human health. We have conducted a limited, preliminary field survey of arsenic levels in soil, flood water, and crops from distinctly different paddy fields in the lower Mekong delta in Vietnam and Cambodia. The purpose of the study was to identify soils and crops (or specific plant parts) that are especially prone to arsenic transfer from soil to crop, and vice versa (i.e. arsenic uptake is prevented in spite of being present in the soil). In addition to arsenic concentration in soil, plant and water, we are examining other elements, such as carbon, nitrogen, sulfur and iron, which give us clues about what chemical and microbial processes that control the overall arsenic uptake.

  5. The environmental geochemistry of Arsenic – An overview

    USGS Publications Warehouse

    Bowell, Robert J; Alpers, Charles N.; Jamieson, Heather E; Nordstrom, D. Kirk; Majzlan, Juraj

    2014-01-01

    Arsenic is one of the most prevalent toxic elements in the environment. The toxicity, mobility, and fate of arsenic in the environment are determined by a complex series of controls dependent on mineralogy, chemical speciation, and biological processes. The element was first described by Theophrastus in 300 B.C. and named arsenikon (also arrhenicon; Caley and Richards 1956) referring to its “potent” nature, although it was originally considered an alternative form of sulfur (Boyle and Jonasson 1973). Arsenikon is believed to be derived from the earlier Persian, zarnik (online etymology dictionary, http://www.etymonline.com/index.php?term=arsenic). It was not until the thirteenth century that an alchemist, Albertus Magnus, was able to isolate the element from orpiment, an arsenic sulfide (As2S3). The complex chemistry required to do this led to arsenic being considered a “bastard metal” or what we now call a “metalloid,” having properties of both metals and non-metals. As a chemical element, arsenic is widely distributed in nature and can be concentrated in many different ways. In the Earth’s crust, arsenic is concentrated by magmatic and hydrothermal processes and has been used as a “pathfinder” for metallic ore deposits, particularly gold, tin, copper, and tungsten (Boyle and Jonasson 1973; Cohen and Bowell 2014). It has for centuries been considered a potent toxin, is a common poison in actual and fictional crimes, and has led to significant impacts on human health in many areas of the world (Cullen 2008; Wharton 2010).

  6. Radioactivity and food

    SciTech Connect

    Olszyna-Marzys, A.E. )

    1990-03-01

    Two topics relating to radioactivity and food are discussed: food irradiation for preservation purposes, and food contamination from radioactive substances. Food irradiation involves the use of electromagnetic energy (x and gamma rays) emitted by radioactive substances or produced by machine in order to destroy the insects and microorganisms present and prevent germination. The sanitary and economic advantages of treating food in this way are discussed. Numerous studies have confirmed that under strictly controlled conditions no undesirable changes take place in food that has been irradiated nor is radioactivity induced. Reference is made to the accident at the Chernobyl nuclear power station, which aroused public concern about irradiated food. The events surrounding the accident are reviewed, and its consequences with regard to contamination of different foods with radioactive substances, particularly iodine-131 and cesium-137, are described. Also discussed are the steps that have been taken by different international organizations to set limits on acceptable radioactivity in food.15 references.

  7. ORNL radioactive waste operations

    SciTech Connect

    Sease, J.D.; King, E.M.; Coobs, J.H.; Row, T.H.

    1982-01-01

    Since its beginning in 1943, ORNL has generated large amounts of solid, liquid, and gaseous radioactive waste material as a by-product of the basic research and development work carried out at the laboratory. The waste system at ORNL has been continually modified and updated to keep pace with the changing release requirements for radioactive wastes. Major upgrading projects are currently in progress. The operating record of ORNL waste operation has been excellent over many years. Recent surveillance of radioactivity in the Oak Ridge environs indicates that atmospheric concentrations of radioactivity were not significantly different from other areas in East Tennesseee. Concentrations of radioactivity in the Clinch River and in fish collected from the river were less than 4% of the permissible concentration and intake guides for individuals in the offsite environment. While some radioactivity was released to the environment from plant operations, the concentrations in all of the media sampled were well below established standards.

  8. On-Line Analysis and Kinetic Behavior of Arsenic Release during Coal Combustion and Pyrolysis.

    PubMed

    Shen, Fenghua; Liu, Jing; Zhang, Zhen; Dai, Jinxin

    2015-11-17

    The kinetic behavior of arsenic (As) release during coal combustion and pyrolysis in a fluidized bed was investigated by applying an on-line analysis system of trace elements in flue gas. This system, based on inductively coupled plasma optical emission spectroscopy (ICP-OES), was developed to measure trace elements concentrations in flue gas quantitatively and continuously. Obvious variations of arsenic concentration in flue gas were observed during coal combustion and pyrolysis, indicating strong influences of atmosphere and temperature on arsenic release behavior. Kinetic laws governing the arsenic release during coal combustion and pyrolysis were determined based on the results of instantaneous arsenic concentration in flue gas. A second-order kinetic law was determined for arsenic release during coal combustion, and the arsenic release during coal pyrolysis followed a fourth-order kinetic law. The results showed that the arsenic release rate during coal pyrolysis was faster than that during coal combustion. Thermodynamic calculations were carried out to identify the forms of arsenic in vapor and solid phases during coal combustion and pyrolysis, respectively. Ca3(AsO4)2 and Ca(AsO2)2 are the possible species resulting from As-Ca interaction during coal combustion. Ca(AsO2)2 is the most probable species during coal pyrolysis.

  9. Concentrations of arsenic, antimony, and boron in steam and steam condensate at The Geysers, California

    USGS Publications Warehouse

    Smith, C.L.; Ficklin, W.H.; Thompson, J.M.

    1987-01-01

    Studies at The Geysers Geothermal Field, California indicate that under some circumstances elements that are transported in the vapor phase can become enriched in the liquid phase. Waters from two condensate traps (steam traps) on steam lines at The Geysers are enriched with arsenic, antimony, and boron compared to the concentrations of these elements in coexisting steam. Concentrations of boron in condensate-trap waters were as high as 160 mg/L, arsenic as high as 35 mg/L, and antimony as high as 200 ??g/L. Enrichment of arsenic, antimony, and boron is at least partially controlled by the partitioning of these elements into the liquid phase, according to their vapor-liquid distribution coefficients, after they are transported in steam. Several of the elements that are most soluble in steam, including arsenic and antimony, are part of the trace-element suite that characterizes precious-metal epithermal ore deposits. ?? 1987.

  10. Evaluation of potential effects of soil available phosphorus on soil arsenic availability and paddy rice inorganic arsenic content.

    PubMed

    Jiang, Wei; Hou, Qingye; Yang, Zhongfang; Zhong, Cong; Zheng, Guodong; Yang, Zhiqiang; Li, Jie

    2014-05-01

    The transfer of arsenic from paddy field to rice is a major exposure route of the highly toxic element to humans. The aim of our study is to explore the effects of soil available phosphorus on As uptake by rice, and identify the effects of soil properties on arsenic transfer from soil to rice under actual field conditions. 56 pairs of topsoil and rice samples were collected. The relevant parameters in soil and the inorganic arsenic in rice grains were analyzed, and then all the results were treated by statistical methods. Results show that the main factors influencing the uptake by rice grain include soil pH and available phosphorus. The eventual impact of phosphorus is identified as the suppression of As uptake by rice grains. The competition for transporters from soil to roots between arsenic and phosphorus in rhizosphere soil has been a dominant feature.

  11. Radioactive Waste Management Basis

    SciTech Connect

    Perkins, B K

    2009-06-03

    The purpose of this Radioactive Waste Management Basis is to describe the systematic approach for planning, executing, and evaluating the management of radioactive waste at LLNL. The implementation of this document will ensure that waste management activities at LLNL are conducted in compliance with the requirements of DOE Order 435.1, Radioactive Waste Management, and the Implementation Guide for DOE Manual 435.1-1, Radioactive Waste Management Manual. Technical justification is provided where methods for meeting the requirements of DOE Order 435.1 deviate from the DOE Manual 435.1-1 and Implementation Guide.

  12. Determination of total arsenic and arsenic species in drinking water, surface water, wastewater, and snow from Wielkopolska, Kujawy-Pomerania, and Lower Silesia provinces, Poland.

    PubMed

    Komorowicz, Izabela; Barałkiewicz, Danuta

    2016-09-01

    Arsenic is a ubiquitous element which may be found in surface water, groundwater, and drinking water. In higher concentrations, this element is considered genotoxic and carcinogenic; thus, its level must be strictly controlled. We investigated the concentration of total arsenic and arsenic species: As(III), As(V), MMA, DMA, and AsB in drinking water, surface water, wastewater, and snow collected from the provinces of Wielkopolska, Kujawy-Pomerania, and Lower Silesia (Poland). The total arsenic was analyzed by inductively coupled plasma mass spectrometry (ICP-MS), and arsenic species were analyzed with use of high-performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC/ICP-MS). Obtained results revealed that maximum total arsenic concentration determined in drinking water samples was equal to 1.01 μg L(-1). The highest concentration of total arsenic in surface water, equal to 3778 μg L(-1) was determined in Trująca Stream situated in the area affected by geogenic arsenic contamination. Total arsenic concentration in wastewater samples was comparable to those determined in drinking water samples. However, significantly higher arsenic concentration, equal to 83.1 ± 5.9 μg L(-1), was found in a snow sample collected in Legnica. As(V) was present in all of the investigated samples, and in most of them, it was the sole species observed. However, in snow sample collected in Legnica, more than 97 % of the determined concentration, amounting to 81 ± 11 μg L(-1), was in the form of As(III), the most toxic arsenic species.

  13. PATHWAY OF INORGANIC ARSENIC METABOLISM

    EPA Science Inventory

    A remarkable aspect of the metabolism of inorganic arsenic in humans is its conversion to methylated metabolites. These metabolites account for most of the arsenic found in urine after exposure to inorganic arsenic. At least some of the adverse health effects attributed to inor...

  14. PROPOSED CARCINOGENIC MECHANISMS FOR ARSENIC

    EPA Science Inventory

    PROPOSED CARCINOGENIC MECHANISMS FOR ARSENIC.

    Arsenic is a human carcinogen in skin, lung, liver, urinary bladder and kidney. In contrast,
    there is no accepted experimental animal model of inorganic arsenic carcinogenesis.
    Proposed mechanisms/modes of action for a...

  15. ARSENIC REMOVAL COST ESTIMATING PROGRAM

    EPA Science Inventory

    The Arsenic Removal Cost Estimating program (Excel) calculates the costs for using adsorptive media and anion exchange treatment systems to remove arsenic from drinking water. The program is an easy-to-use tool to estimate capital and operating costs for three types of arsenic re...

  16. ARSENIC REMOVAL COST ESTIMATING PROGRAM

    EPA Science Inventory

    The Arsenic Removal Cost Estimating program (Excel) calculates the costs for using adsorptive media and anion exchange treatment systems to remove arsenic from drinking water. The program is an easy-to-use tool to estimate capital and operating costs for three types of arsenic re...

  17. PROPOSED CARCINOGENIC MECHANISMS FOR ARSENIC

    EPA Science Inventory

    PROPOSED CARCINOGENIC MECHANISMS FOR ARSENIC.

    Arsenic is a human carcinogen in skin, lung, liver, urinary bladder and kidney. In contrast,
    there is no accepted experimental animal model of inorganic arsenic carcinogenesis.
    Proposed mechanisms/modes of action for a...

  18. A novel arsenic removal process for water using cupric oxide nanoparticles.

    PubMed

    Reddy, K J; McDonald, K J; King, H

    2013-05-01

    Recent studies suggest that the cupric oxide (CuO) nanoparticles effectively adsorb aqueous arsenic species under a wide range of water chemistries. However, to develop CuO nanotechnology to a field application level, further studies are necessary. Batch adsorption kinetic experiments were conducted to determine the time course of uptake of arsenic by CuO nanoparticles. A reactor with CuO nanoparticles was developed to conduct continuous flow-through experiments to filter arsenic from groundwater samples. Groundwater samples spiked with 100 μg/L of arsenic were passed through (1L/h) the flow-through reactor. Samples from the flow-through reactor were collected at a regular interval and analyzed for arsenic and other chemical components (e.g., pH, major and trace elements). The CuO nanoparticles adsorbed with arsenic were regenerated with a sodium hydroxide (NaOH) solution and tested again in the flow-through reactor. Three natural groundwater samples with above 10 μg/L of arsenic were also tested with the flow-through reactor. The arsenic adsorption process by CuO nanoparticles was kinetically rapid and followed the pseudo-second-order rate. The continuous flow-through reactor with CuO nanoparticles was effective in filtering arsenic from spiked or natural groundwater. The regenerated CuO nanoparticles were also effective in filtering arsenic from groundwater. Arsenic mass balance data from regeneration studies suggested that 99% of input arsenic concentration was recovered. The CuO nanoparticle treatment did not show any discernible effects on the chemical quality of groundwater samples. Results of this study suggest that CuO nanoparticles show potential for developing a simple process for field applications to remove arsenic from water.

  19. Toxic Compounds in Our Food: Arsenic Uptake By Rice and Potential Mitigation By Silicon

    NASA Astrophysics Data System (ADS)

    Seyfferth, A.; Gill, R.; Penido, E.

    2014-12-01

    Arsenic is a ubiquitous element in soils worldwide and has the potential to negatively impact human and ecosystem health under certain biogeochemical conditions. While arsenic is relatively immobile in most oxidized soils due to a high affinity for soil solids, arsenic becomes mobilized under reduced soil conditions due to the reductive dissolution of iron(III) oxides thereby releasing soil-bound arsenic. Since arsenic is a well-known carcinogen, this plant-soil process has the potential to negatively impact the lives of billions of rice consumers worldwide upon plant uptake and grain storage of released arsenic. Moreover, arsenic uptake by rice is excacerbated by the use of As-laden groundwater for rice irrigation. One proposed strategy to decrease arsenic uptake by rice plants is via an increase in dissolved silicon in paddy soil solution (pore-water), since silicic acid and arsenous acid share an uptake pathway. However, several soil processes that influence arsenic cycling may be affected by silicon including desorption from bulk soil, formation and mineralogy of iron(III) oxide plaque, and adsorption/desorption onto/from iron plaque; the effect of silicon on these soil processes will ultimately dictate the effectiveness of altered dissolved silicon in decreasing arsenic uptake at the root, which in turn dictates the concentration of arsenic found in grains. Furthermore, the source of silicon may impact carbon cycling and, in particular, methane emissions. Here, impacts of altered dissolved silicon on processes that affect rhizospheric biogeochemical cycling of arsenic and subsequent plant-uptake, and how it influences other biogeochemical cycles such as carbon and iron are investigated. We show that silicon can decrease arsenic uptake and grain storage under certain conditions, and that altered silicon affects the type of iron (III) oxide that comprises iron plaque.

  20. Arsenic (+3 oxidation state) methyltransferase and the methylation of arsenicals in the invertebrate chordate Ciona intestinalis

    EPA Science Inventory

    Biotransformation of inorganic arsenic (iAs) involves methylation catalyzed by arsenic (+3 oxidation state) methyltransferase (As3mt), yielding mono- , di- , and trimethylated arsenicals. To investigate the evolution of molecular mechanisms that mediate arsenic biotransformation,...

  1. Arsenic (+3 oxidation state) methyltransferase and the methylation of arsenicals in the invertebrate chordate Ciona intestinalis

    EPA Science Inventory

    Biotransformation of inorganic arsenic (iAs) involves methylation catalyzed by arsenic (+3 oxidation state) methyltransferase (As3mt), yielding mono- , di- , and trimethylated arsenicals. To investigate the evolution of molecular mechanisms that mediate arsenic biotransformation,...

  2. Low radioactivity spectral gamma calibration facility

    SciTech Connect

    Mathews, M.A.; Bowman, H.R.; Huang, L., H.; Lavelle, M.J.; Smith, A.R.; Hearst, J.R.; Wollenberg, H.A.; Flexser, S.

    1986-01-01

    A low radioactivity calibration facility has been constructed at the Nevada Test Site (NTS). This facility has four calibration models of natural stone that are 3 ft in diameter and 6 ft long, with a 12 in. cored borehole in the center of each model and a lead-shielded run pipe below each model. These models have been analyzed by laboratory natural gamma ray spectroscopy (NGRS) and neutron activation analysis (NAA) for their K, U, and Th content. Also, 42 other elements were analyzed in the NAA. The /sup 222/Rn emanation data were collected. Calibrating the spectral gamma tool in this low radioactivity calibration facility allows the spectral gamma log to accurately aid in the recognition and mapping of subsurface stratigraphic units and alteration features associated with unusual concentrations of these radioactive elements, such as clay-rich zones.

  3. Landscape of two-proton radioactivity.

    PubMed

    Olsen, E; Pfützner, M; Birge, N; Brown, M; Nazarewicz, W; Perhac, A

    2013-05-31

    Ground-state two-proton (2p) radioactivity is a decay mode found in isotopes of elements with even atomic numbers located beyond the two-proton drip line. So far, this exotic process has been experimentally observed in a few light- and medium-mass nuclides with Z≤30. In this study, using state-of-the-art nuclear density functional theory, we globally analyze 2p radioactivity and for the first time identify 2p-decay candidates in elements heavier than strontium. We predict a few cases where the competition between 2p emission and α decay may be observed. In nuclei above lead, the α-decay mode is found to be dominating and no measurable candidates for the 2p radioactivity are expected.

  4. Complexity of Arsenic Biogeochemistry in Surface Water Systems as Influenced by a Hydrologic Event

    NASA Astrophysics Data System (ADS)

    Markley, C. T.; Herbert, B. E.

    2006-12-01

    The arsenic cycle in oxic, surface water environments is often controlled by oxy-hydroxide minerals through sorption/desorption and precipitation/dissolution reactions. However, there are numerous instances where these minerals are found in low concentrations and/or are minimally reactive with respect to aqueous arsenic species. The presence of other anions may competitively inhibit arsenic sorption to oxy-hydroxide surfaces, thus increasing the bioavailability of arsenic and the potential toxic impacts. Microbe-mediated reactions can further impact arsenic fate and transport through accumulation and biotransformation. Arsenic biotransformation via reduction and/or methylation may result in an increased proportion of thermodynamically unfavorable arsenic species such as arsenite and methylated arsenicals in oxic surface waters. The reduced arsenic species, arsenite, is considered more mobile and toxic than the oxic species, arsenate while methylated arsenicals are often considered less toxic species. The complexity of these biogeochemical characteristics highlights the importance of studying arsenic in surface water environments. Particulate and aqueous phase metals (Fe, Mn, Al) and anions (As, P, S) were measured in surface water samples collected from the outflow creek of an arsenic-contaminated lake at high and low flow rates. Arsenic speciation, quantified via HPLC-ICP-MS, was dominated by methylated arsenicals at concentrations up to 82.7 μg/l. The common oxide-forming elements, Fe, Mn and Al were measured via ICP-AES at concentrations up to 2.4 mg/l, 0.88 mg/l and 3.3 mg/l, respectively. However, arsenic was not associated with the particulate phase mineralogy, being approximately 100% in the aqueous (< 0.2 μm ) phase, indicating high arsenic bioavailability. High alkalinity, phosphorous and sulfur concentrations up to 516 mgHCO3/meq, 2.0mg/l and 50 mg/l, respectively, likely out-competed arsenic for sorption to these oxide mineral surfaces. Geochemical

  5. Characterizations of intracellular arsenic in a bacterium

    NASA Astrophysics Data System (ADS)

    Wolfe-Simon, F.; Yannone, S. M.; Tainer, J. A.

    2011-12-01

    Life requires a key set of chemical elements to sustain growth. Yet, a growing body of literature suggests that microbes can alter their nutritional requirements based on the availability of these chemical elements. Under limiting conditions for one element microbes have been shown to utilize a variety of other elements to serve similar functions often (but not always) in similar molecular structures. Well-characterized elemental exchanges include manganese for iron, tungsten for molybdenum and sulfur for phosphorus or oxygen. These exchanges can be found in a wide variety of biomolecules ranging from protein to lipids and DNA. Recent evidence suggested that arsenic, as arsenate or As(V), was taken up and incorporated into the cellular material of the bacterium GFAJ-1. The evidence was interpreted to support As(V) acting in an analogous role to phosphate. We will therefore discuss our ongoing efforts to characterize intracellular arsenate and how it may partition among the cellular fractions of the microbial isolate GFAJ-1 when exposed to As(V) in the presence of various levels of phosphate. Under high As(V) conditions, cells express a dramatically different proteome than when grown given only phosphate. Ongoing studies on the diversity and potential role of proteins and metabolites produced in the presence of As(V) will be reported. These investigations promise to inform the role and additional metabolic potential for As in biology. Arsenic assimilation into biomolecules contributes to the expanding set of chemical elements utilized by microbes in unusual environmental niches.

  6. SHIPPING CONTAINER FOR RADIOACTIVE MATERIAL

    DOEpatents

    Nachbar, H.D.; Biggs, B.B.; Tariello, P.J.; George, K.O.

    1963-01-15

    A shipping container is described for transponting a large number of radioactive nuclear fuel element modules which produce a substantial amount of heat. The container comprises a primary pressure vessel and shield, and a rotatable head having an access port that can be indexed with module holders in the container. In order to remove heat generated in the fuel eleme nts, a heat exchanger is arranged within the container and in contact with a heat exchange fluid therein. The heat exchanger communicates with additional external heat exchangers, which dissipate heat to the atmosphere. (AEC)

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

    NASA Astrophysics Data System (ADS)

    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.

  8. Arsenic and fluoride: two major ground water pollutants.

    PubMed

    Chouhan, Swapnila; Flora, S J S

    2010-07-01

    Increasing human activities have modified the global cycle of heavy metals, non metals and metalloids. Both arsenic and fluoride are ubiquitous in the environment. Thousands of people are suffering from the toxic effects of arsenicals and fluorides in many countries all over the world. These two elements are recognized worldwide as the most serious inorganic contaminants in drinking water. Many studies have reported as regards to simple fluorosis and arsenicosis, but the knowledge of the joint action of these two elements is lacking and the results derived from previous studies were inconclusive. Contradictory results were reported in experimental studies in which different joint actions such as independent, synergistic and antagonistic effects were observed. This indicates that interaction mechanism of these two elements is considerable complicated and requires extensive studies. When two different types of toxicants are simultaneously going inside a human body they may function independently or can act as synergistic or antagonistic to one another. Thus there is an urge to resolve the question that how arsenic and fluoride act in condition of concomitant exposure. Although there have been reports in literature of individual toxicity of arsenic and fluoride however, there is very little known about the effects following the combined exposure to these toxicants. This review focused on recent developments in the research on the condition of individual exposure to arsenic and fluoride along with the recent updates of their combined exposure to better understand the joint action of these two toxicants.

  9. Radioactive waste disposal package

    DOEpatents

    Lampe, Robert F.

    1986-01-01

    A radioactive waste disposal package comprising a canister for containing vitrified radioactive waste material and a sealed outer shell encapsulating the canister. A solid block of filler material is supported in said shell and convertible into a liquid state for flow into the space between the canister and outer shell and subsequently hardened to form a solid, impervious layer occupying such space.

  10. A Remote Radioactivity Experiment

    ERIC Educational Resources Information Center

    Jona, Kemi; Vondracek, Mark

    2013-01-01

    Imagine a high school with very few experimental resources and limited budgets that prevent the purchase of even basic laboratory equipment. For example, many high schools do not have the means of experimentally studying radioactivity because they lack Geiger counters and/or good radioactive sources. This was the case at the first high school one…

  11. A Remote Radioactivity Experiment

    ERIC Educational Resources Information Center

    Jona, Kemi; Vondracek, Mark

    2013-01-01

    Imagine a high school with very few experimental resources and limited budgets that prevent the purchase of even basic laboratory equipment. For example, many high schools do not have the means of experimentally studying radioactivity because they lack Geiger counters and/or good radioactive sources. This was the case at the first high school one…

  12. Radioactive waste disposal package

    DOEpatents

    Lampe, Robert F.

    1986-11-04

    A radioactive waste disposal package comprising a canister for containing vitrified radioactive waste material and a sealed outer shell encapsulating the canister. A solid block of filler material is supported in said shell and convertible into a liquid state for flow into the space between the canister and outer shell and subsequently hardened to form a solid, impervious layer occupying such space.

  13. Radioactive Wastes. Revised.

    ERIC Educational Resources Information Center

    Fox, Charles H.

    This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. This booklet deals with the handling, processing and disposal of radioactive wastes. Among the topics discussed are: The Nature of Radioactive Wastes; Waste Management; and Research and Development. There are…

  14. Temporary Personal Radioactivity

    NASA Astrophysics Data System (ADS)

    Myers, Fred

    2012-11-01

    As part of a bone scan procedure to look for the spread of prostate cancer, I was injected with radioactive technetium. In an effort to occupy/distract my mind, I used a Geiger counter to determine if the radioactive count obeyed the inverse-square law as a sensor was moved away from my bladder by incremental distances.

  15. Sampling for Airborne Radioactivity

    DTIC Science & Technology

    2007-10-01

    compared to betas, gammas and neutrons. For an airborne radioactivity detection system, it is most important to be able to detect alpha particles and... Airborne radioactive particles may emit alpha, beta, gamma or neutron radiation, depending on which radioisotope is present. From a health perspective...

  16. Transportation of Radioactive Materials

    DTIC Science & Technology

    1955-07-01

    measurements of radiation must be made with a Landsverk- Wollan Electrometer Model L-100 or equally efficient standardized meter. Acceptable instruments... Wollan Electrometer Model L-100, or equally efficient standardized meter. 40 146.25-25. Exemptions for radioactive materials: (a) Radioactive materials

  17. Canister arrangement for storing radioactive waste

    DOEpatents

    Lorenzo, D.K.; Van Cleve, J.E. Jr.

    1980-04-23

    The subject invention relates to a canister arrangement for jointly storing high level radioactive chemical waste and metallic waste resulting from the reprocessing of nuclear reactor fuel elements. A cylindrical steel canister is provided with an elongated centrally disposed billet of the metallic waste and the chemical waste in vitreous form is disposed in the annulus surrounding the billet.

  18. Canister arrangement for storing radioactive waste

    DOEpatents

    Lorenzo, Donald K.; Van Cleve, Jr., John E.

    1982-01-01

    The subject invention relates to a canister arrangement for jointly storing high level radioactive chemical waste and metallic waste resulting from the reprocessing of nuclear reactor fuel elements. A cylindrical steel canister is provided with an elongated centrally disposed billet of the metallic waste and the chemical waste in vitreous form is disposed in the annulus surrounding the billet.

  19. Arsenic speciation in rice cereals for infants.

    PubMed

    Juskelis, Rima; Li, Wanxing; Nelson, Jenny; Cappozzo, Jack C

    2013-11-13

    The aim of this study was to conduct a survey of arsenic (As) content in rice cereals for infants. The analysis was based on the FDA Elemental Analysis Manual (EAM 4.11). An inductively coupled plasma mass spectrometer (ICP-MS) was used to determine total As. Due to the different toxicities of the chemical forms of arsenic, the ICP-MS coupled to a high-performance liquid chromatograph (HPLC) was used to perform As speciation. The total and speciated arsenic was determined in 31 different infant rice cereals sold in U.S. supermarkets. The mass fraction of total inorganic As (iAs; sum of arsenite As(III) and arsenate As(V)) concentrations ranged between 55.5 ± 1.3 and 158.0 ± 6.0 μg/kg. The average total arsenic and iAs concentrations in infant rice cereal were 174.4 and 101.4 μg/kg, respectively. There was no substantial difference in iAs levels between organic and conventional rice cereals. The mixed-grain rice cereal contained the least total (105 μg/kg) and inorganic arsenic (63 μg/kg). The major detected organoarsenical species was dimethylarsinic acid (DMA). Monomethylarsonic acid (MMA) was not detected, or only trace levels were found. Spiked sample percent recoveries for iAs, DMA, and MMA ranged from a low of 97.3% for iAs to a high of 115.0% for DMA. Results for speciated and total As in the National Institute of Standards and Technology standard reference material rice flour (NIST SRM 1568) were in good agreement with certified values. In the NIST SRM 1568 sample (n = 5) repeatability (%RSD) was 2.8% for iAs, 1.7% for DMA and species sum, and 5.3% for the total arsenic by As total method. The average percent mass balance was 99.9 ± 6.3% for the NIST SRM 1568 sample. This study provides new and much needed information on arsenic levels in rice-based infant cereals.

  20. Arsenic Speciation of Terrestrial Invertebrates

    SciTech Connect

    Moriarty, M.M.; Koch, I.; Gordon, R.A.; Reimer, K.J. ); )

    2009-07-01

    The distribution and chemical form (speciation) of arsenic in terrestrial food chains determines both the amount of arsenic available to higher organisms, and the toxicity of this metalloid in affected ecosystems. Invertebrates are part of complex terrestrial food webs. This paper provides arsenic concentrations and arsenic speciation profiles for eight orders of terrestrial invertebrates collected at three historical gold mine sites and one background site in Nova Scotia, Canada. Total arsenic concentrations, determined by inductively coupled plasma mass spectrometry (ICP-MS), were dependent upon the classification of invertebrate. Arsenic species were determined by high-performance liquid chromatography (HPLC) ICP-MS and X-ray absorption spectroscopy (XAS). Invertebrates were found by HPLC ICP-MS to contain predominantly arsenite and arsenate in methanol/water extracts, while XAS revealed that most arsenic is bound to sulfur in vivo. Examination of the spatial distribution of arsenic within an ant tissue highlighted the differences between exogenous and endogenous arsenic, as well as the extent to which arsenic is transformed upon ingestion. Similar arsenic speciation patterns for invertebrate groups were observed across sites. Trace amounts of arsenobetaine and arsenocholine were identified in slugs, ants, and spiders.

  1. Environmental Source of Arsenic Exposure

    PubMed Central

    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 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. PMID:25284196

  2. Environmental source of arsenic exposure.

    PubMed

    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.

  3. Reconnaissance of radioactive rocks of Maine

    USGS Publications Warehouse

    Nelson, John M.; Narten, Perry F.

    1951-01-01

    The state of Maine was traversed with car-mounted Geiger-Mueller equipment in the late summer of 1948 and the radioactivity of approximately 4,600 miles of road was logged. All samples were analyzed, both in the field by comparing the radioactivity of each sample to the radioactivity of a stranded measured with a simple scaling modification of a portable counter, and in the Geological Survey’s Trace Elements Section Washington Laboratory. Differences between both types of analyses were negligible. The maximum equivalent uranium content of the most radioactive rocks thus analyzed was 0.008 percent. A 1,400-square-mile abnormally radioactive province in southwestern Maine was outlined. The outcrop data obtained from car traversing are evaluated statistically. Cumulative frequency distribution curves are drawn to show the distribution of outcrops at various levels of radioactivity, and straight-line extensions are made to show to maximum probable grade for various rock types and areas in Maine. A maximum grade of 0.055 percent equivalent uranium is thus predicted for the entire state. This prediction necessarily is a broad generalization because large areas of Main are inaccessible for car traversing. A concept of evaluation of an area for possible mineral deposits is proposed on the basis of lithology, and observed and indicated ranges in grade.

  4. ELUCIDATING THE PATHWAY FOR ARSENIC METHYLATION

    EPA Science Inventory

    Enzymatically-catalyzed methylation of arsenic is part of a metabolic pathway that converts inorganic arsenic into methylated products. Hence, in humans chronically exposed to inorganic arsenic, methyl and dimethyl arsenic account for most of the arsenic that is excreted in the ...

  5. ARSENIC SPECIATION ANALYSIS IN HUMAN SALIVA

    EPA Science Inventory

    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 ...

  6. EPA STUDIES OF ARSENIC SPECIATION IN SEAFOOD MATRICES WITH AN EMPHASIS ON EXTRACTABILITY AND ARSENOSUGAR INTEGRITY

    EPA Science Inventory

    The anthropogenic and geological occurrence of arsenic (As) results in human exposure to a potentially carcinogenic element. The two predominant pathways to As exposure are drinking water (DW) and dietary ingestion (DI). DW exposures are almost exclusively toxic inorganic As. ...

  7. EPA STUDIES OF ARSENIC SPECIATION IN SEAFOOD MATRICES WITH AN EMPHASIS ON EXTRACTABILITY AND ARSENOSUGAR INTEGRITY

    EPA Science Inventory

    The anthropogenic and geological occurrence of arsenic (As) results in human exposure to a potentially carcinogenic element. The two predominant pathways to As exposure are drinking water (DW) and dietary ingestion (DI). DW exposures are almost exclusively toxic inorganic As. ...

  8. Role of arsenic and its resistance in nature.

    PubMed

    Kaur, Sukhvinder; Kamli, Majid Rasool; Ali, Arif

    2011-10-01

    Contamination of the environment with heavy metals has increased drastically over the last few decades. The heavy metals that are toxic include mercury, cadmium, arsenic, and selenium. Of these heavy metals, arsenic is one of the most important global environmental pollutants and is a persistent bioaccumulative carcinogen. It is a toxic metalloid that exists in two major inorganic forms: arsenate and arsenite. Arsenite disrupts enzymatic functions in cells, while arsenate behaves as a phosphate analog and interferes with phosphate uptake and utilization. Despite its toxicity, arsenic may be actively sequestered in plant and animal tissues. Various microbes interact with this metal and have shown resistance to arsenic exposure, and they appear to possess the ars operon for arsenic resistance consisting of three to five genes, i.e., arsRBC or arsRDABC, organized into a single transcriptional unit; some microbes even use it for respiration. Microbial interactions with metals may have several implications for the environment. Microbes may play a role in cycling of toxic heavy metals and in remediation of metal-contaminated sites. There is a correlation between tolerance to heavy metals and antibiotic resistance, a global problem currently threatening the treatment of infections in plants, animals, and humans. The purpose of this review is to highlight the nature and role of toxic arsenic in bacterial systems and to discuss the various genes responsible for this heavy-metal resistance in nature and the mechanisms to detoxify this element.

  9. Arsenic removal by coagulation

    SciTech Connect

    Scott, K.N.; Green, J.F.; Do, H.D.; McLean, S.J.

    1995-04-01

    This study evaluated the removal of naturally occurring arsenic in a full-scale (106-mgd) conventional treatment plant. When the source water was treated with 3--10 mg/L of ferric chloride or 6, 10, or 20 mg/L of alum, arsenic removal was 81--96% (ferric chloride) and 23--71% (alum). Metal concentrations in the sludge produced during this study were below the state`s current hazardous waste levels at all coagulant dosages. No operational difficulties were encountered.

  10. Biochemistry of arsenic detoxification.

    PubMed

    Rosen, Barry P

    2002-10-02

    All living organisms have systems for arsenic detoxification. The common themes are (a) uptake of As(V) in the form of arsenate by phosphate transporters, (b) uptake of As(III) in the form of arsenite by aquaglyceroporins, (c) reduction of As(V) to As(III) by arsenate reductases, and (d) extrusion or sequestration of As(III). While the overall schemes for arsenic resistance are similar in prokaryotes and eukaryotes, some of the specific proteins are the products of separate evolutionary pathways.

  11. Arsenic doped zinc oxide

    SciTech Connect

    Volbers, N.; Lautenschlaeger, S.; Leichtweiss, T.; Laufer, A.; Graubner, S.; Meyer, B. K.; Potzger, K.; Zhou Shengqiang

    2008-06-15

    As-doping of zinc oxide has been approached by ion implantation and chemical vapor deposition. The effect of thermal annealing on the implanted samples has been investigated by using secondary ion mass spectrometry and Rutherford backscattering/channeling geometry. The crystal damage, the distribution of the arsenic, the diffusion of impurities, and the formation of secondary phases is discussed. For the thin films grown by vapor deposition, the composition has been determined with regard to the growth parameters. The bonding state of arsenic was investigated for both series of samples using x-ray photoelectron spectroscopy.

  12. Speciation and toxicity of arsenic in mining-affected lake sediments in the Quinsam watershed, British Columbia.

    PubMed

    Moriarty, Maeve M; Lai, Vivian W-M; Koch, Iris; Cui, Longpeng; Combs, Chris; Krupp, Eva M; Feldmann, Jörg; Cullen, William R; Reimer, Kenneth J

    2014-01-01

    Anthropogenic arsenic inputs into fresh water lakes in the Quinsam watershed, British Columbia, were probed by using multiple methods of inquiry including sediment coring combined with (210)Pb dating, a principal components analysis of elemental composition of sediments, arsenic speciation, bioaccessibility, and toxicity testing. The quantification of arsenic inputs from anthropogenic sources was not trivial because a variety of processes redistribute the element throughout lakes. However, elevated arsenic and sulfate concentrations in Long Lake, a lake that receives arsenic from a seep, suggest that this lake is influenced by mine operations. X-ray absorption near edge structure (XANES) spectra reveal similar arsenic speciation for all sediments within the studied lakes. Bioaccessibility tests, which in this study were used to approximate the solubility and availability of arsenic to benthic organisms, indicate moderate bioaccessibility of arsenic in sediments (7.9-35%). Toxicity testing indicates that not all benthic organisms should be used for evaluating arsenic toxicity, and suggests that the amphipod, Corophium volutator, shows promise as a candidate for widespread use for arsenic sediment toxicity testing. © 2013.

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

    PubMed

    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.

  14. ARSENIC REMOVAL TREATMENT OPTIONS FOR SINGLE FAMILY HOMES

    EPA Science Inventory

    The presentation provides information on POU and POE arsenic removal drinking water treatment systems. The presentation provides information on the arsenic rule, arsenic chemistry and arsenic treatment. The arsenic treatment options proposed for POU and POE treatment consist prim...

  15. Biogeochemistry of arsenic and antimony in the North Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Cutter, Gregory A.; Cutter, Lynda S.

    2006-05-01

    The biogeochemical cycles of the metalloid elements arsenic and antimony were examined along a 15,000 km surface water transect and at 9 vertical profile stations in the western North Pacific Ocean as part of the 2002 IOC Contaminant Baseline Survey. Results show that the speciation of dissolved arsenic (As III, As V, and methylated As) was subtly controlled by the arsenate (AsV)/phosphate ratio. An additional fraction of presumed organic arsenic previously reported in coastal waters was also present (˜15% of the total As) in oceanic surface waters. Dissolved inorganic antimony displayed mildly scavenged behavior that was confirmed by correlations with aluminum, but atmospheric inputs that may be anthropogenic in origin also affected its concentrations. Monomethyl antimony, the predominant organic form of the element, behaved almost conservatively throughout the water column, radically changing the known biogeochemical cycle of antimony.

  16. Invertebrates control metals and arsenic sequestration as ecosystem engineers.

    PubMed

    Schaller, Jörg; Weiske, Arndt; Mkandawire, Martin; Dudel, E Gert

    2010-03-01

    Organic sediments are known to be a significant sink of inorganic elements in polluted freshwater ecosystems. Hence, we investigated the role of invertebrate shredders (the freshwater shrimp Gammarus pulex L.) in metal and arsenic enrichment into organic partitions of sediments in a wetland stream at former uranium mining site. Metal and metalloid content in leaf litter increased significantly during decomposition, while at the same time the carbon content decreased. During decomposition, G. pulex as a ecosystem engineer facilitated significantly the enrichment of magnesium (250%), manganese (560%), cobalt (310%), copper (200%), zinc (43%), arsenic (670%), cadmium (100%) and lead (1340%) into small particle sizes. The enrichments occur under very high concentrations of dissolved organic carbon. Small particles have high surface area that results in high biofilm development. Further, the highest amounts of elements were observed in biofilms. Therefore, invertebrate shredder like G. pulex can enhance retention of large amounts of metal and arsenic in wetlands.

  17. Life Redefined: Microbes Built with Arsenic

    SciTech Connect

    Webb, Sam

    2011-03-22

    Life can survive in many harsh environments, from extreme heat to the presence of deadly chemicals. However, life as we know it has always been based on the same six elements -- carbon, oxygen, nitrogen, hydrogen, sulfur and phosphorus. Now it appears that even this rule has an exception. In the saline and poisonous environment of Mono Lake, researchers have found a bacterium that can grow by incorporating arsenic into its structure in place of phosphorus. X-ray images taken at SLAC's synchrotron light source reveal that this microbe may even use arsenic as a building block for DNA. Please join us as we describe this discovery, which rewrites the textbook description of how living cells work.

  18. [Arsenic speciation in edible plants: a review].

    PubMed

    Liu, Xiao-juan; Lin, Ai-jun; Sun, Guo-xin; Liu, Yun-xia; Liu, Wen-ju

    2010-07-01

    Arsenic (As) is a ubiquitous chemical element in environment, and the increasingly serious As pollution is highly concerned all over the world. China has been considered as one of the countries and regions with serious As pollution in the world by the World Health Organization (WHO). Recent studies indicated that food is one of the major contributors of As in human diets. Edible plants are essential in the diet structure in human life, which often contain high level of As. However, the total As in food can not exactly reflect the toxicity of As, while As speciation closely relates to the As bio-toxicity. Inorganic arsenic is verified as the carcinogen based on human epidemiological data. This paper reviewed the As species in edible plants, their bio-toxicity, and analytical methods.

  19. Groundwater Arsenic Contamination in Kopruoren Basin (Kutahya), Turkey

    NASA Astrophysics Data System (ADS)

    Arslan, S.; Dokuz, U.; Celik, M.; Cheng, Z.

    2012-12-01

    Groundwater quality in the Kopruoren Basin located to the west of Kutahya city in western Anatolia was investigated. Kopruoren Basin is about 275 km2 with about 6,000 residents, but the surface and ground-water quality in this basin impacts a much larger population since the area is located upstream of Kutahya and Eskisehir plains. Groundwater occurs under confined conditions in the limestones of Pliocene units. The only silver deposit of Turkey is developed in the metamorphic basement rocks, Early Miocene volcanics and Pliocene units near Gumuskoy. The amount of silver manufactured annually comprises about 1% of the World's Silver Production. The cyanide-rich wastes of the Eti Gumus silver plant is stored in waste pools. There have been debates about the safety of this facility after a major collapse occurred in one of the pools in May 2011. In this study samples from 31 wells and 21 springs were collected in July and October 2011 and May 2012. The groundwaters are of Ca-Mg-HCO3 type, with arsenic, zinc and antimony occurring at high concentrations. Dissolved arsenic concentrations are as high as 48 ug/L in springs and 734 ug/L in well water. Arsenic in 57% of the springs and 68% of the wells exceeded the WHO guideline value (10 ug/L). Natural sources of arsenic in the area include the dissolution of arsenic-rich minerals such as realgar and orpiment associated with the mineral deposits in the southern part of the study area. In the northern part, arsenic is enriched due to the dissolution of arsenic-bearing coal deposits. Besides these natural sources of contamination, the silver mining activity could be an important anthropogenic source. The leakage of cyanide and arsenic, together with other trace elements to the environment from the waste pools, will continue to poison the environment if necessary precautions are not taken immediately.

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

    PubMed

    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.

  1. Cancer in Experimental Animals Exposed to Arsenic and Arsenic Compounds

    PubMed Central

    Tokar, Erik J.; Benbrahim-Tallaa, Lamia; Ward, Jerold M.; Lunn, Ruth; Sams, Reeder L.; Waalkes, Michael P.

    2011-01-01

    Inorganic arsenic is a ubiquitous environmental contaminant that has long been considered a human carcinogen. Recent studies raise further concern about the metalloid as a major, naturally occurring carcinogen in the environment. However, during this same period it has proven difficult to provide experimental evidence of the carcinogenicity of inorganic arsenic in laboratory animals and, until recently, there was considered to be a lack of clear evidence for carcinogenicity of any arsenical in animals. More recent work with arsenical methylation metabolites and early life exposures to inorganic arsenic has now provided evidence of carcinogenicity in rodents. Given that tens of millions of people worldwide are exposed to potentially unhealthy levels of environmental arsenic, in vivo rodent models of arsenic carcinogenesis are a clear necessity for resolving critical issues, like mechanisms of action, target tissue specificity, and sensitive subpopulations, and in developing strategies to reduce cancers in exposed human populations. This work reviews the available rodent studies considered relevant to carcinogenic assessment of arsenicals, taking advantage of the most recent review by the International Agency for Research on Cancer (IARC) that has not yet appeared as a full monograph but has been summarized (IARC 2009). Many valid studies show that arsenic can interact with other carcinogens/agents to enhance oncogenesis, and help elucidate mechanisms, and these too are summarized in this review. Finally, this body of rodent work is discussed in light of its impact on mechanisms and in the context of the persistent argument that arsenic is not carcinogenic in animals. PMID:20812815

  2. A Remote Radioactivity Experiment

    NASA Astrophysics Data System (ADS)

    Jona, Kemi; Vondracek, Mark

    2013-01-01

    Imagine a high school with very few experimental resources and limited budgets that prevent the purchase of even basic laboratory equipment. For example, many high schools do not have the means of experimentally studying radioactivity because they lack Geiger counters and/or good radioactive sources. This was the case at the first high school one of us (MV) worked at, and after talking with numerous colleagues we know this is still the case at many schools. What options are there then for physics teachers to allow their students to experimentally investigate certain characteristics of radioactivity, such as how distance affects the intensity of radiation coming from a radioactive source? There are computer simulations that can be run, or perhaps the teacher has a light sensor and tries to make an analogy between the intensity of light from a light bulb and the intensity of radiation from a radioactive source based on geometric arguments to get an inverse-square law. But for many there is no direct experimental option if one does not possess a Geiger counter and good radioactive sample. It is for that teacher and class of students that an online, remote radioactivity experiment was created.

  3. Elevated trimethylarsine oxide (TMAO) and inorganic arsenic in northern hemisphere summer monsoonal wet deposition.

    PubMed

    Savage, Laurie; Carey, Manus Patrick; Hossain, Mahmud; Islam, M Rafiqul; de Silva, P Mangala C S; Williams, Paul Nicholas; Meharg, Andrew A

    2017-10-04

    Arsenic speciation, their inputs, for wet deposition are not well understood. Here we demonstrate that trimethylarsine oxide (TMAO) and inorganic arsenic are the dominant species in summer, Indian subcontinent, Bangladesh, monsoonal, wet deposition, with inorganic arsenic dominating, accounting for ~80% of total arsenic in this medium. Lower concentrations of both species were found in the winter, Indian subcontinent, Sri Lankan, monsoonal, wet deposition. The only other species present was dimethylarsinic acid (DMAA), but this was usually below limits of detection (LoD). We hypothesise that TMAO and inorganic arsenic in monsoonal wet deposition is predominantly of marine origin. For TMAO, the potential source is the atmospheric oxidation of marine derived trimethyl arsine (TMA). For inorganic arsenic, our evidence suggests entrainment of water column inorganic arsenic into atmospheric particulates. These conclusions are based on weather trajectory analysis, and to the strong correlations with known wet deposition marine derived elements: boron, iodine and selenium. The finding that TMAO and inorganic arsenic are widely present, and elevated, in monsoonal wet deposition identifies major knowledge gaps that need to be addressed regarding understanding arsenic's global cycle.

  4. Environmental arsenic exposure and DNA methylation of the tumor suppressor gene p16 and the DNA repair gene MLH1: effect of arsenic metabolism and genotype.

    PubMed

    Hossain, Mohammad Bakhtiar; Vahter, Marie; Concha, Gabriela; Broberg, Karin

    2012-11-01

    Arsenic is carcinogenic, possibly partly through epigenetic mechanisms. We evaluated the effects of arsenic exposure and metabolism on DNA methylation. Arsenic exposure and methylation efficiency in 202 women in the Argentinean Andes were assessed from concentrations of arsenic metabolites in urine (inorganic arsenic, methylarsonic acid [MMA], and dimethylarsinic acid [DMA]), measured by HPLC-ICPMS. Methylation of CpGs of the tumor suppressor gene p16, the DNA repair gene MLH1, and the repetitive elements LINE1 was measured by PCR pyrosequencing of blood DNA. Genotyping (N = 172) for AS3MT was performed using Sequenom™, and gene expression (N = 90) using Illumina DirectHyb HumanHT-12 v3.0. Median arsenic concentration in urine was 230 μg L(-1) (range 10.1-1251). In linear regression analysis, log(2)-transformed urinary arsenic concentrations were positively associated with methylation of p16 (β = 0.14, P = 0.0028) and MLH1 (β = 0.28, P = 0.0011), but not with LINE1. Arsenic concentrations were of borderline significance negatively correlated with expression of p16 (r(s) = -0.20; P = 0.066)), but not with MLH1. The fraction of inorganic arsenic was positively (β = 0.026; P = 0.010) and DMA was negatively (β = -0.017, P = 0.043) associated with p16 methylation with no effect of MMA. Carriers of the slow-metabolizing AS3MT haplotype were associated with more p16 methylation (P = 0.022). Arsenic exposure was correlated with increased methylation, in blood, of genes encoding enzymes that suppress carcinogenesis, and the arsenic metabolism efficiency modified the degree of epigenetic alterations.

  5. Amphoteric arsenic in GaN

    SciTech Connect

    Wahl, U.; Correia, J. G.; Araujo, J. P.; Rita, E.; Soares, J. C.

    2007-04-30

    The authors have determined the lattice location of implanted arsenic in GaN by means of conversion electron emission channeling from radioactive {sup 73}As. They give direct evidence that As is an amphoteric impurity, thus settling the long-standing question as to whether it prefers cation or anion sites in GaN. The amphoteric character of As and the fact that As{sub Ga} 'antisites' are not minority defects provide additional aspects to be taken into account for an explanantion of the so-called miscibility gap in ternary GaAs{sub 1-x}N{sub x} compounds, which cannot be grown with a single phase for values of x in the range of 0.1

  6. [Inventories of atmospheric arsenic emissions from coal combustion in China, 2005].

    PubMed

    Tian, He-Zhong; Qu, Yi-Ping

    2009-04-15

    Anthropogenic arsenic (As) emitted from coal combustion is one of key trace elements leading to negative air pollution and national economy loss. It is of great significance to estimate the atmospheric arsenic emission for proposing relevant laws or regulations and selecting proper pollution control technologies. The inventories of atmospheric arsenic emissions from coal combustion in China were evaluated by adopting the emission factor method based on fuel consumption. Arsenic emission sources were firstly classified into several categories by economic sectors, combustion types and pollution control technologies. Then, according to provincial coal consumption and averaged arsenic concentration in the feed fuel, the inventories of atmospheric arsenic emission from coal combustion in China in 2005 were established. Coal outputand consumption in China in 2005 were 2,119.8 and 2,099.8 Mt, respectively. The total emissions of arsenic released into the atmosphere in 2005 in China were estimated at about 1,564.4 t, and Shandong ranked the largest province with 144.4 t arsenic release, followed by Hunan (141.1 t), Hebei (108.5 t), Henan (77.7 t), and Jiangsu (77.0 t), which were mainly concentrated in the eastern and central provinces of China. The arsenic emissions were largely emitted by industry sector (818.8 t) and thermal power generation sector (303.4 t), contributing 52.3% and 19.4% of the totals, respectively. About 375.5 t arsenic was estimated to be released into the atmosphere in the form of gas phase in China in 2005, with a share of 24% of the totals. In general, arsenic pollution control from coal combustion should be highlighted for the power and industry sectors in the whole country. However, arsenic poisoning caused by residential coal burning should also be paid great attention in some areas such as Xinjiang, Gansu, Qinghai and Guishou.

  7. Exercise Prevents Memory Impairment Induced by Arsenic Exposure in Mice: Implication of Hippocampal BDNF and CREB

    PubMed Central

    Yu, Zi-Jiang; Yu, Yan; Xiao, Chao-Lun; Kang, Chao-Sheng; Ge, Guo; Linghu, Yan; Zhu, Jun-De; Li, Yu-Mei; Li, Qiang-Ming; Luo, Shi-Peng; Yang, Dang; Li, Lin; Zhang, Wen-Yan; Tian, Guang

    2015-01-01

    High concentrations of arsenic, which can be occasionally found in drinking water, have been recognized as a global health problem. Exposure to arsenic can disrupt spatial memory; however, the underlying mechanism remains unclear. In the present study, we tested whether exercise could interfere with the effect of arsenic exposure on the long-term memory (LTM) of object recognition in mice. Arsenic (0, 1, 3, and 10 mg/ kg, i.g.) was administered daily for 12 weeks. We found that arsenic at dosages of 1, 3, and 10 mg/kg decreased body weight and increased the arsenic content in the brain. The object recognition LTM (tested 24 h after training) was disrupted by 3 mg/ kg and 10 mg/ kg, but not 1 mg/ kg arsenic exposure. Swimming exercise also prevented LTM impairment induced by 3 mg/ kg, but not with 10 mg/ kg, of arsenic exposure. The expression of brain-derived neurotrophic factor (BDNF) and phosphorylated cAMP-response element binding protein (pCREB) in the CA1 and dentate gyrus areas (DG) of the dorsal hippocampus were decreased by 3 mg/ kg and 10 mg/ kg, but not by 1 mg/ kg, of arsenic exposure. The decrease in BDNF and pCREB in the CA1 and DG induced by 3 mg/ kg, but not 10 mg/ kg, of arsenic exposure were prevented by swimming exercise. Arsenic exposure did not affect the total CREB expression in the CA1 or DG. Taken together, these results indicated that swimming exercise prevented the impairment of object recognition LTM induced by arsenic exposure, which may be mediated by BDNF and CREB in the dorsal hippocampus. PMID:26368803

  8. Atherosclerosis induced by arsenic in drinking water in rats through altering lipid metabolism

    SciTech Connect

    Cheng, Tain-Junn; Chuu, Jiunn-Jye; Chang, Chia-Yu; Tsai, Wan-Chen; Chen, Kuan-Jung; Guo, How-Ran

    2011-10-15

    Arsenic in drinking water is a global environmental health problem, and the exposure may increase cardiovascular and cerebrovascular diseases mortalities, most likely through causing atherosclerosis. However, the mechanism of atherosclerosis formation after arsenic exposure is still unclear. To study the mechanism of atherosclerosis formation after arsenic exposure and explore the role of high cholesterol diet (HCD) in this process, we fed spontaneous hypertensive rats and Wistar Kyoto rats with basal diet or HCD and provided with them drinking water containing arsenic at different ages and orders for 20 consecutive weeks. We measured high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), total cholesterol, triglycerides, heat shock protein 70 (HSP 70), and high sensitive C-reactive protein (hs-CRP) at predetermined intervals and determined expressions of cholesteryl ester transfer protein-1 (CETP-1) and liver X receptor {beta} (LXR{beta}) in the liver. Atherosclerosis was determined by examining the aorta with hematoxylin and eosin stain. After 20 weeks, we found arsenic, alone or combined with HCD, may promote atherosclerosis formation with transient increases in HSP 70 and hs-CRP. Early combination exposure decreased the HDL-C/LDL-C ratio without changing the levels of total cholesterol and triglyceride until 30 weeks old. Both CETP-1 and LXR{beta} activities were suppressed, most significantly in early combination exposure. In conclusion, arsenic exposure may induce atherosclerosis through modifying reverse cholesterol transport in cholesterol metabolism and suppressing LXR{beta} and CEPT-1 expressions. For decreasing atherosclerosis related mortality associated with arsenic, preventing exposure from environmental sources in early life is an important element. - Highlights: > Arsenic causes cardiovascular and cerebrovascular diseases through atherosclerosis. > Arsenic may promote atherosclerosis with transient increase in HSP

  9. Exercise Prevents Memory Impairment Induced by Arsenic Exposure in Mice: Implication of Hippocampal BDNF and CREB.

    PubMed

    Sun, Bao-Fei; Wang, Qing-Qing; Yu, Zi-Jiang; Yu, Yan; Xiao, Chao-Lun; Kang, Chao-Sheng; Ge, Guo; Linghu, Yan; Zhu, Jun-De; Li, Yu-Mei; Li, Qiang-Ming; Luo, Shi-Peng; Yang, Dang; Li, Lin; Zhang, Wen-Yan; Tian, Guang

    2015-01-01

    High concentrations of arsenic, which can be occasionally found in drinking water, have been recognized as a global health problem. Exposure to arsenic can disrupt spatial memory; however, the underlying mechanism remains unclear. In the present study, we tested whether exercise could interfere with the effect of arsenic exposure on the long-term memory (LTM) of object recognition in mice. Arsenic (0, 1, 3, and 10 mg/ kg, i.g.) was administered daily for 12 weeks. We found that arsenic at dosages of 1, 3, and 10 mg/kg decreased body weight and increased the arsenic content in the brain. The object recognition LTM (tested 24 h after training) was disrupted by 3 mg/ kg and 10 mg/ kg, but not 1 mg/ kg arsenic exposure. Swimming exercise also prevented LTM impairment induced by 3 mg/ kg, but not with 10 mg/ kg, of arsenic exposure. The expression of brain-derived neurotrophic factor (BDNF) and phosphorylated cAMP-response element binding protein (pCREB) in the CA1 and dentate gyrus areas (DG) of the dorsal hippocampus were decreased by 3 mg/ kg and 10 mg/ kg, but not by 1 mg/ kg, of arsenic exposure. The decrease in BDNF and pCREB in the CA1 and DG induced by 3 mg/ kg, but not 10 mg/ kg, of arsenic exposure were prevented by swimming exercise. Arsenic exposure did not affect the total CREB expression in the CA1 or DG. Taken together, these results indicated that swimming exercise prevented the impairment of object recognition LTM induced by arsenic exposure, which may be mediated by BDNF and CREB in the dorsal hippocampus.

  10. Arsenic and diabetes: current perspectives.

    PubMed

    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

  11. Acute and chronic arsenic toxicity

    PubMed Central

    Ratnaike, R

    2003-01-01

    Arsenic toxicity is a global health problem affecting many millions of people. Contamination is caused by arsenic from natural geological sources leaching into aquifers, contaminating drinking water and may also occur from mining and other industrial processes. Arsenic is present as a contaminant in many traditional remedies. Arsenic trioxide is now used to treat acute promyelocytic leukaemia. Absorption occurs predominantly from ingestion from the small intestine, though minimal absorption occurs from skin contact and inhalation. Arsenic exerts its toxicity by inactivating up to 200 enzymes, especially those involved in cellular energy pathways and DNA synthesis and repair. Acute arsenic poisoning is associated initially with nausea, vomiting, abdominal pain, and severe diarrhoea. Encephalopathy and peripheral neuropathy are reported. Chronic arsenic toxicity results in multisystem disease. Arsenic is a well documented human carcinogen affecting numerous organs. There are no evidence based treatment regimens to treat chronic arsenic poisoning but antioxidants have been advocated, though benefit is not proven. The focus of management is to reduce arsenic ingestion from drinking water and there is increasing emphasis on using alternative supplies of water. PMID:12897217

  12. Arsenic in shrimp from Kuwait

    SciTech Connect

    Bou-Olayan, A.H.; Al-Yakoob, S.; Al-Hossaini, M.

    1995-04-01

    Arsenic is ubiquitous in the environment and can accumulate in food via contaminated soil, water or air. It enters the food chain through dry and wet atmospheric deposition. Combustion of oil and coal, use of arsenical fertilizers and pesticides and smelting of ores contributes significantly to the natural background of arsenic in soils and sediments. The metal can be transferred from soil to man through plants. In spite of variation in acute, subacute, and chronic toxic effects to plants and animals, evidence of nutritional essentiality of arsenic for rats, goats, and guinea pigs has been suggested, but has not been confirmed for humans. Adverse toxic effects of arsenic as well as its widespread distribution in the environment raises concern about levels of arsenic in man`s diet. Higher levels of arsenic in the diet can result in a higher accumulation rate. Arsenic levels in marine organisms are influenced by species differences, size of organism, and human activities. Bottom dwellers such as shrimp, crab, and lobster accumulate more arsenic than fish due to their frequent contact with bottom sediments. Shrimp constitute approximately 30% of mean total seafood consumption in Kuwait. This study was designed to determine the accumulation of arsenic in the commercially important jinga shrimp (Metapenaeus affinis) and grooved tiger prawn (Penaeus semisulcatus). 13 refs., 3 figs., 1 tab.

  13. Acute and chronic arsenic toxicity.

    PubMed

    Ratnaike, R N

    2003-07-01

    Arsenic toxicity is a global health problem affecting many millions of people. Contamination is caused by arsenic from natural geological sources leaching into aquifers, contaminating drinking water and may also occur from mining and other industrial processes. Arsenic is present as a contaminant in many traditional remedies. Arsenic trioxide is now used to treat acute promyelocytic leukaemia. Absorption occurs predominantly from ingestion from the small intestine, though minimal absorption occurs from skin contact and inhalation. Arsenic exerts its toxicity by inactivating up to 200 enzymes, especially those involved in cellular energy pathways and DNA synthesis and repair. Acute arsenic poisoning is associated initially with nausea, vomiting, abdominal pain, and severe diarrhoea. Encephalopathy and peripheral neuropathy are reported. Chronic arsenic toxicity results in multisystem disease. Arsenic is a well documented human carcinogen affecting numerous organs. There are no evidence based treatment regimens to treat chronic arsenic poisoning but antioxidants have been advocated, though benefit is not proven. The focus of management is to reduce arsenic ingestion from drinking water and there is increasing emphasis on using alternative supplies of water.

  14. Arsenic Content in American Wine.

    PubMed

    Wilson, Denise

    2015-10-01

    Recent studies that have investigated arsenic content in juice, rice, milk, broth (beef and chicken), and other foods have stimulated an interest in understanding how prevalent arsenic contamination is in the U.S. food and beverage supply. The study described here focused on quantifying arsenic levels in wine. A total of 65 representative wines from the top four wine-producing states in the U.S. were analyzed for arsenic content. All samples contained arsenic levels that exceeded the U.S. Environmental Protection Agency (U.S. EPA) exposure limit for drinking water of 10 parts per billion (ppb) and all samples contained inorganic arsenic. The average arsenic detected among all samples studied was 23.3 ppb. Lead, a common co-contaminant to arsenic, was detected in 58% of samples tested, but only 5% exceeded the U.S. EPA exposure limit for drinking water of 15 ppb. Arsenic levels in American wines exceeded those found in other studies involving water, bottled water, apple juice, apple juice blend, milk, rice syrup, and other beverages. When taken in the context of consumption patterns in the U.S., the pervasive presence of arsenic in wine can pose a potential health risk to regular adult wine drinkers.

  15. ARSENIC TREATMENT OPTIONS

    EPA Science Inventory

    The PPT presentation will provide information on the drinking water treatment options for small utilities to remove arsenic from ground water. The discussion will include information on the EPA BAT listed processes and on some of the newer technologies, such as the iron based ad...

  16. Microbial Transformation of Arsenic

    NASA Astrophysics Data System (ADS)

    Stolz, J. F.

    2004-12-01

    Whether the source is natural or anthropogenic, it has become evident that arsenic is readily transformed by a great diversity of microbial species and has a robust biogeochemical cycle. Arsenic cycling primarily involves the oxidation of As(III) and the reduction of As(V). Over thirty arsenite oxidizing prokaryotes have been reported and include alpha, beta, and gamma Proteobacteria , Deinocci and Crenarchaeota. At least twenty species of arsenate-respiring prokaryotes are now known and include Crenarchaeota, thermophilic bacteria, low and high G+C gram positive bacteria, and gamma, delta, and epsilon Proteobacteria. These organisms are metabolically diverse, and depending on the species, capable of using other terminal electron acceptors (e.g., nitrate, selenate, fumarate, sulfate). In addition to inorganic forms (e.g., sodium arsenate) organoarsenicals can be utilized as a substrate. The feed additive roxarsone (3-nitro-4-hydroxyphenyl arsonic acid) has been shown to readily degrade leading to the release of inorganic arsenic (e.g., As(V)). Degradation proceeds via the cleavage of the arsenate functional group or the reduction of the nitro functional group and deamination. The rapid degradation (within 3 days) of roxarsone by Clostridium sp. strain OhILAs appears to follow the latter pathway and may involve Stickland reactions. The activities of these organisms affect the speciation and mobilization of arsenic, ultimately impacting water quality.

  17. What are Spent Nuclear Fuel and High-Level Radioactive Waste ?

    SciTech Connect

    DOE

    2002-12-01

    Spent nuclear fuel and high-level radioactive waste are materials from nuclear power plants and government defense programs. These materials contain highly radioactive elements, such as cesium, strontium, technetium, and neptunium. Some of these elements will remain radioactive for a few years, while others will be radioactive for millions of years. Exposure to such radioactive materials can cause human health problems. Scientists worldwide agree that the safest way to manage these materials is to dispose of them deep underground in what is called a geologic repository.

  18. Understanding radioactive waste

    SciTech Connect

    Murray, R.L.

    1981-12-01

    This document contains information on all aspects of radioactive wastes. Facts are presented about radioactive wastes simply, clearly and in an unbiased manner which makes the information readily accessible to the interested public. The contents are as follows: questions and concerns about wastes; atoms and chemistry; radioactivity; kinds of radiation; biological effects of radiation; radiation standards and protection; fission and fission products; the Manhattan Project; defense and development; uses of isotopes and radiation; classification of wastes; spent fuels from nuclear reactors; storage of spent fuel; reprocessing, recycling, and resources; uranium mill tailings; low-level wastes; transportation; methods of handling high-level nuclear wastes; project salt vault; multiple barrier approach; research on waste isolation; legal requiremnts; the national waste management program; societal aspects of radioactive wastes; perspectives; glossary; appendix A (scientific American articles); appendix B (reference material on wastes). (ATT)

  19. Mobilization of Arsenic in Groundwater of Holocene Delta, Indian Segment

    NASA Astrophysics Data System (ADS)

    Chatterjee, D.

    2007-12-01

    often enriched with DOC ( range- 1.2- 7.0 mg/L) where as deep aquifers ( 100- 304 m ) are relatively containing low amount of DOC ( 0.4- 1.9 mg/L). This reflects the influence of local processes at shallow depths where oxidative as well as microbial degeneration of carbon sink is playing crucial role in arsenic mobilization. This also suggests that the break down of organic matter is the principal process in the shallow reducing aquifers with high/low arsenic along with high / low - coupled redox sensitive species and DOC. The presence of DOC in shallow aquifers also indicates that organic matter is relatively young and more reactive. High PCO2 values, relatively high redox sensitive elements, low Eh and absence of DO are the hydrogeochemical fingerprints of the BDP shallow aquifers. Delta building processes are also important to explain arsenic sourcing and mobilization (deeper arsenics- bearing middle delta aquifers with low concentration of chloride as well as deeper saline tidal deposits aquifers of lower delta with / without low arsenic). Both the deeper aquifers are also containing high bicarbonate. This indicates that mineral carbonates (both simple and complex) are also playing important role in arsenic mobilization at least in deeper aquifers. The study also deals with the role of secondary minerals (mica/clay) in arsenic mobilization. The XPS studies on mica further strengthen that the surface chemistry and role of Fe (II) are also important issue to understand the difference of high/low arsenic in between shallow and deep aquifers in BDP.

  20. Temporary Personal Radioactivity

    ERIC Educational Resources Information Center

    Myers, Fred

    2012-01-01

    As part of a bone scan procedure to look for the spread of prostate cancer, I was injected with radioactive technetium. In an effort to occupy/distract my mind, I used a Geiger counter to determine if the radioactive count obeyed the inverse-square law as a sensor was moved away from my bladder by incremental distances. (Contains 1 table and 2…

  1. Dynamic radioactive particle source

    DOEpatents

    Moore, Murray E; Gauss, Adam Benjamin; Justus, Alan Lawrence

    2012-06-26

    A method and apparatus for providing a timed, synchronized dynamic alpha or beta particle source for testing the response of continuous air monitors (CAMs) for airborne alpha or beta emitters is provided. The method includes providing a radioactive source; placing the radioactive source inside the detection volume of a CAM; and introducing an alpha or beta-emitting isotope while the CAM is in a normal functioning mode.

  2. Temporary Personal Radioactivity

    ERIC Educational Resources Information Center

    Myers, Fred

    2012-01-01

    As part of a bone scan procedure to look for the spread of prostate cancer, I was injected with radioactive technetium. In an effort to occupy/distract my mind, I used a Geiger counter to determine if the radioactive count obeyed the inverse-square law as a sensor was moved away from my bladder by incremental distances. (Contains 1 table and 2…

  3. Container for radioactive materials

    DOEpatents

    Fields, Stanley R.

    1985-01-01

    A container for housing a plurality of canister assemblies containing radioactive material and disposed in a longitudinally spaced relation within a carrier to form a payload package concentrically mounted within the container. The payload package includes a spacer for each canister assembly, said spacer comprising a base member longitudinally spacing adjacent canister assemblies from each other and a sleeve surrounding the associated canister assembly for centering the same and conducting heat from the radioactive material in a desired flow path.

  4. Radioactive gold ring dermatitis

    SciTech Connect

    Miller, R.A.; Aldrich, J.E. )

    1990-08-01

    A superficial squamous cell carcinoma developed in a woman who wore a radioactive gold ring for more than 30 years. Only part of the ring was radioactive. Radiation dose measurements indicated that the dose to basal skin layer was 2.4 Gy (240 rad) per week. If it is assumed that the woman continually wore her wedding ring for 37 years since purchase, she would have received a maximum dose of approximately 4600 Gy.

  5. Arsenic, microbes and contaminated aquifers

    USGS Publications Warehouse

    Oremland, Ronald S.; Stolz, John F.

    2005-01-01

    The health of tens of millions of people world-wide is at risk from drinking arsenic-contaminated well water. In most cases this arsenic occurs naturally within the sub-surface aquifers, rather than being derived from identifiable point sources of pollution. The mobilization of arsenic into the aqueous phase is the first crucial step in a process that eventually leads to human arsenicosis. Increasing evidence suggests that this is a microbiological phenomenon.

  6. Protective effects of selenium, calcium, and magnesium against arsenic-induced oxidative stress in male rats.

    PubMed

    Srivastava, Deepti; Subramanian, Ramlingam B; Madamwar, Datta; Flora, Swaran J S

    2010-06-01

    Inorganic arsenic is a potent carcinogen and environmental pollutant. More than one hundred million people are reported to be exposed to elevated concentrations of arsenic mainly via drinking water. Essential trace elements can affect toxicity of metals by interacting with metals at the primary site of action and can also modify the body's response to toxic metals by altering their metabolism and transport. This study investigates the effects of concomitant administration of selenium, magnesium, and calcium with arsenic on blood biochemistry and oxidative stress. Selenium was the most effective in reducing arsenic-induced inhibition of blood delta-aminolevulinic acid dehydratase (ALAD) activity and liver oxidative stress. Calcium and magnesium also showed favourable effects on haematological and other biochemical parameters. Because selenium was the most effective, it should be added to chelation therapy to achieve the best protective effects against arsenic poisoning in humans.

  7. Arsenic fixation on iron-hydroxide-rich and plant litter-containing sediments in natural environments

    NASA Astrophysics Data System (ADS)

    Fritzsche, Andreas; Dienemann, Holger; Dudel, Ernst Gert

    2006-10-01

    Iron-hydroxide-rich and plant litter-containing sediments from natural sites contaminated with uranium mine tailing leachates were examined for their ability to adsorb arsenic. The samples with high contents of iron hydroxides (Fetotal concentration, >300 g kg-1) exhibited remarkable fixation of arsenic (up to 40 g As kg-1). This value corresponded approximately to the supersaturation point for natural iron hydroxides under the present conditions, and it was significantly lower than the value found for synthetic iron hydroxides. There was a strong correlation ( R=0.8999) between the concentration of iron and that of arsenic at low arsenic contents, indicating adsorption on strong binding sites. Although all the samples had noticeable contents of organic carbon (plant litter), calcium, and manganese, no obvious effect of these elements on arsenic fixation could be detected. The amount of iron hydroxides was found the only fixation-controlling parameter immediately below a leaching water source.

  8. Arsenic content of homeopathic medicines

    SciTech Connect

    Kerr, H.D.; Saryan, L.A.

    1986-01-01

    In order to test the widely held assumption that homeopathic medicines contain negligible quantities of their major ingredients, six such medicines labeled in Latin as containing arsenic were purchased over the counter and by mail order and their arsenic contents measured. Values determined were similar to those expected from label information in only two of six and were markedly at variance in the remaining four. Arsenic was present in notable quantities in two preparations. Most sales personnel interviewed could not identify arsenic as being an ingredient in these preparations and were therefore incapable of warning the general public of possible dangers from ingestion. No such warnings appeared on the labels.

  9. Arsenic poisoning of Bangladesh groundwater

    NASA Astrophysics Data System (ADS)

    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.

  10. Responses of wild small mammals to arsenic pollution at a partially remediated mining site in Southern France.

    PubMed

    Drouhot, Séverine; Raoul, Francis; Crini, Nadia; Tougard, Christelle; Prudent, Anne-Sophie; Druart, Coline; Rieffel, Dominique; Lambert, Jean-Claude; Tête, Nicolas; Giraudoux, Patrick; Scheifler, Renaud

    2014-02-01

    Partial remediation actions at a former gold mine in Southern France led to a mosaic of contaminated and rehabilitated zones. In this study, the distribution of arsenic and its potential adverse effects on small mammals were investigated. The effectiveness of remediation for reducing the transfer of this element into wildlife was also discussed. Arsenic levels were measured in the soil and in the stomach contents, livers, kidneys, and lungs of four small mammal species (the wood mouse (Apodemus sylvaticus), the Algerian mouse (Mus spretus), the common vole (Microtus arvalis), and the greater white-toothed shrew (Crocidura russula)). The animals were caught at the former extraction site, in zones with three different levels of remediation treatments, and at a control site. Arsenic concentrations in the soil were highly spatially heterogeneous (ranging from 29 to 18,900 μg g(-1)). Despite the decrease in arsenic concentrations in the remediated soils, both wood mice and Algerian mice experienced higher oral exposure to arsenic in remediated zones than in the control area. The accumulated arsenic in their organs showed higher intra-zonal variability than the arsenic distribution in the soil, suggesting that, in addition to remediation processes, other variables can help explain arsenic transfer to wildlife, such as the habitat and diet preferences of the animals or their mobility. A weak but significant correlation between arsenic concentration and body condition was observed, and weak relationships between the liver/kidney/lung mass and arsenic levels were also detected, suggesting possible histological alterations. © 2013.

  11. Culturable associated-bacteria of the sponge Theonella swinhoei show tolerance to high arsenic concentrations

    PubMed Central

    Keren, Ray; Lavy, Adi; Mayzel, Boaz; Ilan, Micha

    2015-01-01

    Sponges are potent filter feeders and as such are exposed to high fluxes of toxic trace elements, which can accumulate in their body over time. Such is the case of the Red Sea sponge Theonella swinhoei, which has been shown to accumulate up to 8500 mg/Kg of the highly toxicelement arsenic. T. swinhoei is known to harbor a multitude of sponge-associated bacteria, so it is hypothesized that the associated-bacteria will be tolerant to high arsenic concentration. This study also investigates the fate of the arsenic accumulated in the sponge to test if the associated-bacteria have an important role in the arsenic accumulation process of their host, since bacteria are key players in the natural arsenic cycle. Separation of the sponge to sponge cells and bacteria enriched fractions showed that arsenic is accumulated by the bacteria. Sponge-associated, arsenic-tolerant bacteria were cultured in the presence of 5 mM of either arsenate or arsenite (equivalent to 6150 mg/Kg arsenic, dry weight). The 54 isolated bacteria were grouped to 15 operational taxonomic units (OTUs) and isolates belonging to 12 OTUs were assessed for tolerance to arsenate at increased concentrations up to 100 mM. Eight of the 12 OTUs tolerated an order of magnitude increase in the concentration of arsenate, and some exhibited external biomineralization of arsenic–magnesium salts. The biomineralization of this unique mineral was directly observed in bacteria for the first time. These results may provide an explanation for the ability of the sponge to accumulate considerable amounts of arsenic. Furthermore arsenic-mineralizing bacteria can potentially be used for the study of bioremediation, as arsenic toxicity affects millions of people worldwide. PMID:25762993

  12. Arsenic contamination in water, soil, sediment and rice of central India.

    PubMed

    Patel, K S; Shrivas, K; Brandt, R; Jakubowski, N; Corns, W; Hoffmann, P

    2005-04-01

    Arsenic contamination in the environment (i.e. surface, well and tube-well water, soil, sediment and rice samples) of central India (i.e. Ambagarh Chauki, Chhattisgarh) is reported. The concentration of the total arsenic in the samples i.e. water (n = 64), soil (n = 30), sediment (n = 27) and rice grain (n = 10) were ranged from 15 to 825 microg L(-1), 9 to 390 mg kg(-1), 19 to 489 mg kg(-1) and 0.018 to 0.446 mg kg(-1), respectively. In all type of waters, the arsenic levels exceeded the permissible limit, 10 microg L(-1). The most toxic and mobile inorganic species i.e. As(III) and As(V) are predominantly present in water of this region. The soils have relatively higher contents of arsenic and other elements i.e. Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Ga, Zr, Sn, Sb, Pb and U. The mean arsenic contents in soil of this region are much higher than in arsenic soil of West Bengal and Bangladesh. The lowest level of arsenic in the soil of this region is 3.7 mg kg(-1) with median value of 9.5 mg kg(-1). The arsenic contents in the sediments are at least 2-folds higher than in the soil. The sources of arsenic contamination in the soil of this region are expected from the rock weathering as well as the atmospheric deposition. The environmental samples i.e. water, soil dust, food, etc. are expected the major exposure for the arsenic contamination. The most of people living in this region are suffering with arsenic borne diseases (i.e. melanosis, keratosis, skin cancer, etc.).

  13. Arsenic and fluoride in the groundwater of Mexico.

    PubMed

    Armienta, M A; Segovia, N

    2008-08-01

    Concentrations of arsenic and fluoride above Mexican drinking water standards have been detected in aquifers of various areas of Mexico. This contamination has been found to be mainly caused by natural sources. However, the specific processes releasing these toxic elements into groundwater have been determined in a few zones only. Many studies, focused on arsenic-related health effects, have been performed at Comarca Lagunera in northern México. High concentrations of fluoride in water were also found in this area. The origin of the arsenic there is still controversial. Groundwater in active mining areas has been polluted by both natural and anthropogenic sources. Arsenic-rich minerals contaminate the fractured limestone aquifer at Zimapán, Central México. Tailings and deposits smelter-rich fumes polluted the shallow granular aquifer. Arsenic contamination has also been reported in the San Antonio-El Triunfo mining zone, southern Baja California, and Santa María de la Paz, in San Luis Potosí state. Even in the absence of mining activities, hydrogeochemistry and statistical techniques showed that arsenopyrite oxidation may also contaminate water, as in the case of the Independencia aquifer in the Mexican Altiplano. High concentrations of arsenic have also been detected in geothermal areas like Los Azufres, Los Humeros, and Acoculco. Prevalence of dental fluorosis was revealed by epidemiological studies in Aguascalientes and San Luis Potosí states. Presence of fluoride in water results from dissolution of acid-volcanic rocks. In Mexico, groundwater supplies most drinking water. Current knowledge and the geology of Mexico indicate the need to include arsenic and fluoride determinations in groundwater on a routine basis, and to develop interdisciplinary studies to assess the contaminant's sources in all enriched areas.

  14. Case Report: Potential Arsenic Toxicosis Secondary to Herbal Kelp Supplement

    PubMed Central

    Amster, Eric; Tiwary, Asheesh; Schenker, Marc B.

    2007-01-01

    Context Medicinal use of dietary herbal supplements can cause inadvertent arsenic toxicosis. Case Presentation A 54-year-old woman was referred to the University of California, Davis, Occupational Medicine Clinic with a 2-year history of worsening alopecia and memory loss. She also reported having a rash, increasing fatigue, nausea, and vomiting, disabling her to the point where she could no longer work full-time. A thorough exposure history revealed that she took daily kelp supplements. A urine sample showed an arsenic level of 83.6 μg/g creatinine (normal < 50 μg/g creatinine). A sample from her kelp supplements contained 8.5 mg/kg (ppm) arsenic. Within weeks of discontinuing the supplements, her symptoms resolved and arsenic blood and urine levels were undetectable. Discussion To evaluate the extent of arsenic contamination in commercially available kelp, we analyzed nine samples randomly obtained from local health food stores. Eight of the nine samples showed detectable levels of arsenic higher than the Food and Drug Administration tolerance level of 0.5 to 2 ppm for certain food products. None of the supplements contained information regarding the possibility of contamination with arsenic or other heavy metals. The 1994 Dietary Supplement Health and Education Act (DSHEA) has changed the way dietary herbal therapies are marketed and regulated in the United States. Less regulation of dietary herbal therapies will make inadvertent toxicities a more frequent occurrence. Relevance to Clinical Practice Clinicians should be aware of the potential for heavy metal toxicity due to chronic use of dietary herbal supplements. Inquiring about use of dietary supplements is an important element of the medical history. PMID:17450231

  15. Radioactivity in food crops

    SciTech Connect

    Drury, J.S.; Baldauf, M.F.; Daniel, E.W.; Fore, C.S.; Uziel, M.S.

    1983-05-01

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for /sup 137/Cs, /sup 40/K, /sup 90/Sr, /sup 226/Ra, /sup 228/Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for /sup 241/Am, /sup 7/Be, /sup 60/Co, /sup 55/Fe, /sup 3/H, /sup 131/I, /sup 54/Mn, /sup 95/Nb, /sup 210/Pb, /sup 210/Po, /sup 106/Ru, /sup 125/Sb, /sup 228/Th, /sup 232/Th, and /sup 95/Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g/sup -1/ (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins.

  16. Radioactivity in the environment

    SciTech Connect

    Nagel, D.J.; Edson, R.

    1995-12-01

    Natural and man-made radioactivities in the environment have been extensively researched in the second half of this century. Recently, increased attention has been given to (1) radioactive waste willfully placed in the environment by discharges from nuclear reprocessing plants or by dumping at sea, and (2) radioactive materials lost due to accidents in terrestrial (civilian power) or marine (submarine propulsion) reactors. Increasing field measurements, and disclosures of dumping and accidents in the former Soviet Union, are adding greatly to the knowledge of environmental radioactivity. New, more powerful computers are having a double impact. They make possible Geographical Information Systems for geo-referencing and correlating multi-variable datasets. Furthermore, supercomputers enable global atmospheric, oceanographic and terrestrial circulation and transport models, which include physical, chemical and biological processes. We will review exemplary work on the sources, transport, disposition and impact of anthropogenic environmental radioactivity. Such work both provides new knowledge of environmental processes and furnishes the basis for deciding on potential remediation actions.

  17. SEPARATION OF RADIOACTIVE COLUMBIUM TRACER

    DOEpatents

    Glendenin, L.E.; Gest, H.

    1958-08-26

    A process is presented for the recovery of radioactive columbium from solutions containing such columbium together with radioactive tellurium. The columbium and tellurium values are separated from such solutions by means of an inorganic oxide carrier precipitate, such as MnO/sub 2/. This oxide carrier precipitate and its associated columbium and telluriuan values are then dissolved in an aqueous acidic solution and nonradioactive tellurium, in an ionic form, is then introduced into such solution, for example in the form of H/sub 2/TeO/sub 3/. The tellurium present in the solution is then reduced to the elemental state and precipitates, and is then separated from the supernataat solution. A basic acetate precipitate is formed in the supernatant and carries the remaining columblum values therefrom. After separation, this basic ferric acetate precipitate is dissolved, and the ferric ions are removed by means of an organic solvent extraction process utilizing ether. The remaining solution contains carrier-free columbium as its only metal ion.

  18. INFLUENCE OF DIETARY ARSENIC ON URINARY ARSENIC METABOLITE EXCRETION

    EPA Science Inventory

    Influence of Dietary Arsenic on Urinary Arsenic Metabolite Excretion

    Cara 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...

  19. Thiolated arsenicals in arsenic metabolism: Occurrence, formation, and biological implications.

    PubMed

    Sun, Yuzhen; Liu, Guangliang; Cai, Yong

    2016-11-01

    Arsenic (As) is a notoriously toxic pollutant of health concern worldwide with potential risk of cancer induction, but meanwhile it is used as medicines for the treatment of different conditions including hematological cancers. Arsenic can undergo extensive metabolism in biological systems, and both toxicological and therapeutic effects of arsenic compounds are closely related to their metabolism. Recent studies have identified methylated thioarsenicals as a new class of arsenic metabolites in biological systems after exposure of inorganic and organic arsenicals, including arsenite, dimethylarsinic acid (DMA(V)), dimethylarsinous glutathione (DMA(III)GS), and arsenosugars. The increasing detection of thiolated arsenicals, including monomethylmonothioarsonic acid (MMMTA(V)), dimethylmonothioarsinic acid (DMMTA(V)) and its glutathione conjugate (DMMTA(V)GS), and dimethyldithioarsinic acid (DMDTA(V)) suggests that thioarsenicals may be important metabolites and play important roles in arsenic toxicity and therapeutic effects. Here we summarized the reported occurrence of thioarsenicals in biological systems, the possible formation pathways of thioarsenicals, and their toxicity, and discussed the biological implications of thioarsenicals on arsenic metabolism, toxicity, and therapeutic effects. Copyright © 2016. Published by Elsevier B.V.

  20. INFLUENCE OF DIETARY ARSENIC ON URINARY ARSENIC METABOLITE EXCRETION

    EPA Science Inventory

    Influence of Dietary Arsenic on Urinary Arsenic Metabolite Excretion

    Cara 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...

  1. Arsenic toxicity changes in the presence of sediment

    SciTech Connect

    Burton, G.A. Jr.; Lazorchak, J.M.; Waller, W.T.; Lanza, G.R.

    1987-03-01

    Arsenic has been widely used in herbicides resulting in high soil and sediment concentrations in some areas. D. magna has been a commonly used indicator of aquatic toxicity and standardized methods have been developed for acute toxicity testing. Arsenic is quite similar chemically to phosphorus and sulfur, thus it produces toxic effects, in part, by replacing these elements in essential metabolic processes. The effect of sediments on ameliorating metal toxicity to Daphnia has not been reported. However, arsenic and other metalloids/metal are known to concentrate in sediment and adsorb to particulates. This study investigated the effect of sediments on standard arsenite LC50 determinations with D. magna and alkaline phosphatase activity (APA).

  2. Arsenic speciation in edible mushrooms.

    PubMed

    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.

  3. Protective role of ascorbic acid and alpha-tocopherol on arsenic-induced microsomal dysfunctions.

    PubMed

    Ramanathan, K; Shila, S; Kumaran, S; Panneerselvam, C

    2003-03-01

    Arsenic, a naturally occurring element, is present in food, soil, air and water. All human populations are exposed to arsenic and its compounds through occupational or environmental processes. Since arsenic compounds have been shown to exert their toxicity chiefly by generating reactive oxygen species, we have evaluated the effect of ascorbic acid and alpha-tocopherol on oxidative damage, antioxidant status and on xenobiotic metabolizing systems in arsenic-exposed rat liver and kidney microsomes. Arsenic exposure increases oxidative damage to lipids and proteins and decreases the levels of antioxidants and the activities of xenobiotic metabolizing enzymes. Coadministration of ascorbic acid and alpha-tocopherol to arsenic-exposed rats resulted in a reduction in the levels of lipid peroxidation, protein carbonyls and hydrogen peroxide and an elevation in the levels of reduced glutathione, ascorbic acid and alpha-tocopherol. Ascorbic acid and alpha-tocopherol treatment decreases the activity of haem oxygenase, whereas it increases the levels/ activity of cytochrome P450, cytochrome b5 and NADPH-cytochrome P450 reductase in arsenic-intoxicated rats. The results of this study provide evidence that ascorbic acid and alpha-tocopherol supplementation can improve the arsenic-induced altered microsomal functions in liver and kidney.

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

    PubMed

    Kouras, A; Katsoyiannis, I; Voutsa, D

    2007-08-25

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

  5. Arsenic decreases antinociceptive activity of paracetamol: possible involvement of serotonergic and endocannabinoid receptors.

    PubMed

    Vijayakaran, Karunakaran; Kesavan, Manickam; Kannan, Kandasamy; Sankar, Palanisamy; Tandan, Surendra Kumar; Sarkar, Souvendra Nath

    2014-09-01

    We assessed whether repeated arsenic exposure can decrease paracetamol-mediated antinociception by modulating serotonergic and endocannabinoid pathways. Rats were preexposed to elemental arsenic (4ppm) as sodium arsenite through drinking water for 28 days. Next day paracetamol's (400mg/kg, oral) antinociceptive activity was assessed through formalin-induced nociception. Serotonin content and gene expression of 5-HT1A, 5-HT2A and CB1 receptors were evaluated in brainstem and frontal cortex. Arsenic decreased paracetamol-mediated analgesia. Paracetamol, but not arsenic, increased serotonin content in these regions. Arsenic attenuated paracetamol-mediated increase in serotonin level. Paracetamol did not alter 5-HT1A expression, but caused down-regulation of 5-HT2A and up-regulation of CB1 receptors. Arsenic down-regulated these receptors. However, paracetamol-mediated down-regulation of 5-HT2A was more pronounced. Arsenic did not modify paracetamol's effect on 5-HT1A expression, but reduced paracetamol-mediated down-regulation of 5-HT2A and reversed up-regulation of CB1 receptors. Results suggest arsenic reduced paracetamol-induced analgesia possibly by interfering with pronociceptive 5-HT2A and antinociceptive CB1 receptors.

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

    NASA Astrophysics Data System (ADS)

    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.

  7. Radioactivity of Consumer Products

    NASA Astrophysics Data System (ADS)

    Peterson, David; Jokisch, Derek; Fulmer, Philip

    2006-11-01

    A variety of consumer products and household items contain varying amounts of radioactivity. Examples of these items include: FiestaWare and similar glazed china, salt substitute, bananas, brazil nuts, lantern mantles, smoke detectors and depression glass. Many of these items contain natural sources of radioactivity such as Uranium, Thorium, Radium and Potassium. A few contain man-made sources like Americium. This presentation will detail the sources and relative radioactivity of these items (including demonstrations). Further, measurements of the isotopic ratios of Uranium-235 and Uranium-238 in several pieces of china will be compared to historical uses of natural and depleted Uranium. Finally, the presenters will discuss radiation safety as it pertains to the use of these items.

  8. Radioactive Waste Management

    SciTech Connect

    Bales, J.D.; Graham, J.; Boshears, R.

    1996-01-01

    Radioactive Waste Management (RWM) announces on a monthly basis the current worldwide information available on the critical topics of spent-fuel transport and storage, radioactive effluents from nuclear facilities, techniques of processing radioactive wastes, their storage, and ultimate disposal. Information on remedial actions and other environmental aspects is also included. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are other US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange, the International Atomic Energy Agency`s International Nuclear Information System or government-to-government agreements.

  9. Radioactive mixed waste disposal

    SciTech Connect

    Jasen, W.G.; Erpenbeck, E.G.

    1993-02-01

    Various types of waste have been generated during the 50-year history of the Hanford Site. Regulatory changes in the last 20 years have provided the emphasis for better management of these wastes. Interpretations of the Atomic Energy Act of 1954 (AEA), the Resource Conservation and Recovery Act of 1976 (RCRA), and the Hazardous and Solid Waste Amendments (HSWA) have led to the definition of radioactive mixed wastes (RMW). The radioactive and hazardous properties of these wastes have resulted in the initiation of special projects for the management of these wastes. Other solid wastes at the Hanford Site include low-level wastes, transuranic (TRU), and nonradioactive hazardous wastes. This paper describes a system for the treatment, storage, and disposal (TSD) of solid radioactive waste.

  10. Adsorption and desorption characteristics of arsenic onto ceria nanoparticles

    NASA Astrophysics Data System (ADS)

    Feng, Qinzhong; Zhang, Zhiyong; Ma, Yuhui; He, Xiao; Zhao, Yuliang; Chai, Zhifang

    2012-01-01

    The rapid increase in the use of engineered nanoparticles [ENPs] has resulted in an increasing concern over the potential impacts of ENPs on the environmental and human health. ENPs tend to adsorb a large variety of toxic chemicals when they are emitted into the environment, which may enhance the toxicity of ENPs and/or adsorbed chemicals. The study was aimed to investigate the adsorption and desorption behaviors of arsenic on ceria NPs in aqueous solution using batch technique. Results show that the adsorption behavior of arsenic on ceria NPs was strongly dependent on pH and independent of ionic strength, indicating that the electrostatic effect on the adsorption of these elements was relatively not important compared to surface chemical reactions. The adsorption isotherms fitted very well to both the Langmuir and Freundlich models. The thermodynamic parameters (Δ H 0 , Δ S 0 , and Δ G 0 ) for the adsorption of arsenic were determined at three different temperatures of 283, 303, and 323 K. The adsorption reaction was endothermic, and the process of adsorption was favored at high temperature. The desorption data showed that desorption hysteresis occurred at the initial concentration studied. High adsorption capacity of arsenic on ceria NPs suggests that the synergistic effects of ceria NPs and arsenic on the environmental systems may exist when they are released into the environment.

  11. Microbial Methylation of Metalloids: Arsenic, Antimony, and Bismuth

    PubMed Central

    Bentley, Ronald; Chasteen, Thomas G.

    2002-01-01

    A significant 19th century public health problem was that the inhabitants of many houses containing wallpaper decorated with green arsenical pigments experienced illness and death. The problem was caused by certain fungi that grew in the presence of inorganic arsenic to form a toxic, garlic-odored gas. The garlic odor was actually put to use in a very delicate microbiological test for arsenic. In 1933, the gas was shown to be trimethylarsine. It was not until 1971 that arsenic methylation by bacteria was demonstrated. Further research in biomethylation has been facilitated by the development of delicate techniques for the determination of arsenic species. As described in this review, many microorganisms (bacteria, fungi, and yeasts) and animals are now known to biomethylate arsenic, forming both volatile (e.g., methylarsines) and nonvolatile (e.g., methylarsonic acid and dimethylarsinic acid) compounds. The enzymatic mechanisms for this biomethylation are discussed. The microbial conversion of sodium arsenate to trimethylarsine proceeds by alternate reduction and methylation steps, with S-adenosylmethionine as the usual methyl donor. Thiols have important roles in the reductions. In anaerobic bacteria, methylcobalamin may be the donor. The other metalloid elements of the periodic table group 15, antimony and bismuth, also undergo biomethylation to some extent. Trimethylstibine formation by microorganisms is now well established, but this process apparently does not occur in animals. Formation of trimethylbismuth by microorganisms has been reported in a few cases. Microbial methylation plays important roles in the biogeochemical cycling of these metalloid elements and possibly in their detoxification. The wheel has come full circle, and public health considerations are again important. PMID:12040126

  12. Recent Advances in the Measurement of Arsenic, Cadmium, and Mercury in Rice and Other Foods.

    PubMed

    Jackson, Brian P; Punshon, Tracy

    2015-03-01

    Trace element analysis of foods is of increasing importance because of raised consumer awareness and the need to evaluate and establish regulatory guidelines for toxic trace metals and metalloids. This paper reviews recent advances in the analysis of trace elements in food, including challenges, state-of-the-art methods, and use of spatially resolved techniques for localizing the distribution of arsenic and mercury within rice grains. Total elemental analysis of foods is relatively well-established, but the push for ever lower detection limits requires that methods be robust from potential matrix interferences, which can be particularly severe for food. Inductively coupled plasma mass spectrometry (ICP-MS) is the method of choice, allowing for multi-element and highly sensitive analyses. For arsenic, speciation analysis is necessary because the inorganic forms are more likely to be subject to regulatory limits. Chromatographic techniques coupled to ICP-MS are most often used for arsenic speciation, and a range of methods now exist for a variety of different arsenic species in different food matrices. Speciation and spatial analysis of foods, especially rice, can also be achieved with synchrotron techniques. Sensitive analytical techniques and methodological advances provide robust methods for the assessment of several metals in animal- and plant-based foods, particularly for arsenic, cadmium, and mercury in rice and arsenic speciation in foodstuffs.

  13. Container for radioactive materials

    DOEpatents

    Fields, S.R.

    1984-05-30

    A container is claimed for housing a plurality of canister assemblies containing radioactive material. The several canister assemblies are stacked in a longitudinally spaced relation within a carrier to form a payload concentrically mounted within the container. The payload package includes a spacer for each canister assembly, said spacer comprising a base member longitudinally spacing adjacent canister assemblies from each other and sleeve surrounding the associated canister assembly for centering the same and conducting heat from the radioactive material in a desired flow path. 7 figures.

  14. Experience with airborne detection of radioactive pollution (ENMOS, IRIS).

    PubMed

    Pavlik, Bohuslav; Engelsmann, Jan

    2004-01-01

    This paper discusses the advantages of airborne monitoring of radioactive pollution and shows example maps indicating manmade pollution from different sources. The sensitivity of airborne radioactive detection is discussed. Comparisons of airborne and different ground measurements are presented. New instrumentation for airborne or ground moving vehicles is briefly described. Airborne footprinting provides rapid, well-defined spatial images of natural and manmade radioactive contamination. Data acquisition integrated with GPS navigation provides consistent data and guarantees proper data location. Real-time airborne measurements are re-calculated, with the use of special algorithms, into absolute units for individual radioactive nuclei contamination of the ground together with dose calculation. Raw records and calculated data are provided after enhanced post-flight processing. Dose rates and detection of different radioactive elements are presented. (ENMOS is a product of Picodas Group Inc. and IRIS is the product of Pico Envirotec Inc.)

  15. Arsenic Is A Genotoxic Carcinogen

    EPA Science Inventory

    Arsenic is a recognized human carcinogen; however, there is controversy over whether or not it should be considered a genotoxic carcinogen. Many possible modes of action have been proposed on how arsenic induces cancer, including inhibiting DNA repair, altering methylation patter...

  16. ARSENIC - SUSCEPTIBILITY & IN UTERO EFFECTS

    EPA Science Inventory

    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...

  17. Drinking Water Arsenic Rule History

    EPA Pesticide Factsheets

    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.

  18. TREATMENT TECHNOLOGIES FOR ARSENIC REMOVAL

    EPA Science Inventory

    The United States Environmental Protection Agency (US EPA) recently reduced the arsenic maximum contaminant level (MCL) from 0.050 mg/L to 0.010 mg/L. In order to increase arsenic outreach efforts, a summary of the new rule, related health risks, treatment technologies, and desig...

  19. Arsenic Removal from Drinking Water

    EPA Science Inventory

    Web cast presentation covered six topics: 1), Arsenic Chemistry, 2), Technology Selection/Arsenic Demonstration Program, 3), Case Study 1, 4), Case Study 2,5), Case Study 3, and 6), Media Regeneration Project. The presentation consists of material presented at other training sess...

  20. TREATMENT TECHNOLOGIES FOR ARSENIC REMOVAL

    EPA Science Inventory

    The United States Environmental Protection Agency (US EPA) recently reduced the arsenic maximum contaminant level (MCL) from 0.050 mg/L to 0.010 mg/L. In order to increase arsenic outreach efforts, a summary of the new rule, related health risks, treatment technologies, and desig...

  1. ARSENIC - SUSCEPTIBILITY & IN UTERO EFFECTS

    EPA Science Inventory

    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...

  2. Arsenic Is A Genotoxic Carcinogen

    EPA Science Inventory

    Arsenic is a recognized human carcinogen; however, there is controversy over whether or not it should be considered a genotoxic carcinogen. Many possible modes of action have been proposed on how arsenic induces cancer, including inhibiting DNA repair, altering methylation patter...

  3. Enrichment processes of arsenic in oxidic sedimentary rocks - from geochemical and genetic characterization to potential mobility.

    PubMed

    Banning, Andre; Rüde, Thomas R

    2010-11-01

    Sedimentary marine iron ores of Jurassic age and Tertiary marine sandy sediments containing iron hydroxides concretions have been sampled from boreholes and outcrops in two study areas in Germany to examine iron and arsenic accumulation processes. Samples were analyzed for bulk rock geochemistry (INAA/ICP-OES), quantitative mineralogy (XRD with Rietveld analysis), element distribution (electron microprobe) and arsenic fractionation (sequential extraction). Bulk Jurassic ores contain an average arsenic content of 123 μg g(-1) hosted in mainly goethite ooids which slowly formed in times of condensed sedimentation. Enrichment occurred syndepositionally and is therefore characterized as primary. Iron concretions in Tertiary sediments mainly consist of goethite and yield arsenic up to 1860 μg g(-1). The accumulation process is secondary as it took place in the course of oxidation of the originally reduced marine sediments under terrestrial conditions, leading to element redistribution and local enrichment in the near-surface part. The scale of enrichment was assessed calculating Enrichment Factors, indicating that arsenic accumulation was favoured over other potential contaminants. In spite of higher bulk arsenic contents in the oxidic rocks, the mainly pyrite-hosted As pool within the reduced deeper part of the Tertiary sediments is shown to have a higher potential for remobilization and creation of elevated arsenic concentrations in groundwater. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. The role of irrigation techniques in arsenic bioaccumulation in rice (Oryza sativa L.).

    PubMed

    Spanu, Antonino; Daga, Leonardo; Orlandoni, Anna Maria; Sanna, Gavino

    2012-08-07

    The bioaccumulation of arsenic compounds in rice is of great concern worldwide because rice is the staple food for billions of people and arsenic is one of the most toxic and carcinogenic elements at even trace amounts. The uptake of arsenic compounds in rice comes mainly from its interaction with system soil/water in the reducing conditions typical of paddy fields and is influenced by the irrigation used. We demonstrate that the use of sprinkler irrigation produces rice kernels with a concentration of total arsenic about fifty times lower when compared to rice grown under continuous flooding irrigation. The average total amount of arsenic, measured by a fully validated ICP-MS method, in 37 rice grain genotypes grown with sprinkler irrigation was 2.8 ± 2.5 μg kg(-1), whereas the average amount measured in the same genotypes grown under identical conditions, but using continuous flooding irrigation was 163 ± 23 μg kg(-1). In addition, we find that the average concentration of total arsenic in rice grains cultivated under sprinkler irrigation is close to the total arsenic concentration found in irrigation waters. Our results suggest that, in our experimental conditions, the natural bioaccumulation of this element in rice grains may be completely circumvented by adopting an appropriate irrigation technique.

  5. Arsenic Mobility and Groundwater Extraction in Bangladesh

    NASA Astrophysics Data System (ADS)

    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.

  6. Total arsenic in rice milk.

    PubMed

    Shannon, Ron; Rodriguez, Jose M

    2014-01-01

    Rice milk and its by-products were tested for total arsenic concentration. Total arsenic concentration was determined using graphite-furnace atomic absorption spectrometry. The arsenic concentrations ranged from 2.7 ± 0.3 to 17.9 ± 0.5 µg L(-1). Rice milk and its by-products are not clearly defined as food, water or milk substitute. The US Environmental Protection Agency (EPA), the European Union (EU) and the World Health Organization (WHO) have set a level of 10 µg L(-1) for total arsenic concentrations in drinking water. The EU and the US regulatory agencies do not provide any guidelines on total arsenic concentrations in foods. This study provides us with a starting point to address this issue in the State of Mississippi, USA.

  7. Tissue dosimetry, metabolism and excretion of pentavalent and trivalent dimethylated arsenic in mice after oral administration

    SciTech Connect

    Hughes, Michael F. Devesa, Vicenta; Adair, Blakely M.; Conklin, Sean D.; Creed, John T.; Styblo, Miroslav; Kenyon, Elaina M.; Thomas, David J.

    2008-02-15

    Dimethylarsinic acid (DMA(V)) is a rat bladder carcinogen and the major urinary metabolite of administered inorganic arsenic in most mammals. This study examined the disposition of pentavalent and trivalent dimethylated arsenic in mice after acute oral administration. Adult female mice were administered [{sup 14}C]-DMA(V) (0.6 or 60 mg As/kg) and sacrificed serially over 24 h. Tissues and excreta were collected for analysis of radioactivity. Other mice were administered unlabeled DMA(V) (0.6 or 60 mg As/kg) or dimethylarsinous acid (DMA(III)) (0.6 mg As/kg) and sacrificed at 2 or 24 h. Tissues (2 h) and urine (24 h) were collected and analyzed for arsenicals. Absorption, distribution and excretion of [{sup 14}C]-DMA(V) were rapid, as radioactivity was detected in tissues and urine at 0.25 h. For low dose DMA(V) mice, there was a greater fractional absorption of DMA(V) and significantly greater tissue concentrations of radioactivity at several time points. Radioactivity distributed greatest to the liver (1-2% of dose) and declined to less than 0.05% in all tissues examined at 24 h. Urinary excretion of radioactivity was significantly greater in the 0.6 mg As/kg DMA(V) group. Conversely, fecal excretion of radioactivity was significantly greater in the high dose group. Urinary metabolites of DMA(V) included DMA(III), trimethylarsine oxide (TMAO), dimethylthioarsinic acid and trimethylarsine sulfide. Urinary metabolites of DMA(III) included TMAO, dimethylthioarsinic acid and trimethylarsine sulfide. DMA(V) was also excreted by DMA(III)-treated mice, showing its sensitivity to oxidation. TMAO was detected in tissues of the high dose DMA(V) group. The low acute toxicity of DMA(V) in the mouse appears to be due in part to its minimal retention and rapid elimination.

  8. Microbiology: A microbial arsenic cycle in a salt-saturated, extreme environment

    USGS Publications Warehouse

    Oremland, R.S.; Kulp, T.R.; Blum, J.S.; Hoeft, S.E.; Baesman, S.; Miller, L.G.; Stolz, J.F.

    2005-01-01

    Searles Lake is a salt-saturated, alkaline brine unusually rich in the toxic element arsenic. Arsenic speciation changed from arsenate [As(V)] to arsenite [As(III)] with sediment depth. Incubated anoxic sediment slurries displayed dissimilatory As(V)-reductase activity that was markedly stimulated by H2 or sulfide, whereas aerobic slurries had rapid As(III)-oxidase activity. An anaerobic, extremely haloalkaliphilic bacterium was isolated from the sediment that grew via As(V) respiration, using either lactate or sulfide as its electron donor. Hence, a full biogeochemical cycle of arsenic occurs in Searles Lake, driven in part by inorganic electron donors.

  9. Fate of heavy metals and radioactive metals in gasification of sewage sludge.

    PubMed

    Marrero, Thomas W; McAuley, Brendan P; Sutterlin, William R; Steven Morris, J; Manahan, Stanley E

    2004-01-01

    The fates of radioactive cadmium, strontium, cesium, cobalt, arsenic, mercury, zinc, and copper spiked into sewage sludge were determined when the sludge was gasified by a process that maximizes production of char from the sludge (ChemChar process). For the most part the metals were retained in the char product in the gasifier. Small, but measurable quantities of arsenic were mobilized by gasification and slightly more than 1% of the arsenic was detected in the effluent gas. Mercury was largely mobilized from the solids in the gasifier, but most of the mercury was retained in a filter composed of char prepared from the sludge. The small amounts of mercury leaving the gasification system were found to be associated with an aerosol product generated during gasification. The metals retained in the char product of gasification were only partially leachable with 50% concentrated nitric acid.

  10. *Arsenic (+3 oxidation state) methyltransferase and the methylation of arsenicals in the invertebrate chordate ciona intestinalis

    EPA Science Inventory

    Biotransformation of inorganic arsenic (iAs) involves methylation catalyzed by arsenic (+3 oxidation state) methyltransferase (As3mt) , yielding mono-, di-, and trimethylated arsenicals. A comparative genomic approach focused on Ciona intestinaJis, an invertebrate chordate, was u...

  11. *Arsenic (+3 oxidation state) methyltransferase and the methylation of arsenicals in the invertebrate chordate ciona intestinalis

    EPA Science Inventory

    Biotransformation of inorganic arsenic (iAs) involves methylation catalyzed by arsenic (+3 oxidation state) methyltransferase (As3mt) , yielding mono-, di-, and trimethylated arsenicals. A comparative genomic approach focused on Ciona intestinaJis, an invertebrate chordate, was u...

  12. THE ROLE OF PROTEIN BINDING OF TRIVALENT ARSENICALS IN ARSENIC CARCINOGENESIS AND TOXICITY

    EPA Science Inventory

    Three of the most plausible biological theories of arsenic carcinogenesis are protein binding, oxidative stress and altered DNA methylation. This review presents the role of trivalent arsenicals binding to proteins in arsenic carcinogenesis. Using vacuum filtration based receptor...

  13. THE ROLE OF PROTEIN BINDING OF TRIVALENT ARSENICALS IN ARSENIC CARCINOGENESIS AND TOXICITY

    EPA Science Inventory

    Three of the most plausible biological theories of arsenic carcinogenesis are protein binding, oxidative stress and altered DNA methylation. This review presents the role of trivalent arsenicals binding to proteins in arsenic carcinogenesis. Using vacuum filtration based receptor...

  14. Oak Ridge National Laboratory shipping containers for radioactive materials

    SciTech Connect

    Schaich, R.W.

    1980-05-01

    The types of containers used at ORNL for the transport of radioactive materials are described. Both returnable and non-returnable types are included. Containers for solids, liquids and gases are discussed. Casks for the shipment of uranium, irradiated fuel elements, and non-irradiated fuel elements are also described. Specifications are provided. (DC)

  15. Arsenic concentrations in Chinese coals.

    PubMed

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

    2006-03-15

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

  16. AIR RADIOACTIVITY MONITOR

    DOEpatents

    Bradshaw, R.L.; Thomas, J.W.

    1961-04-11

    The monitor is designed to minimize undesirable background buildup. It consists of an elongated column containing peripheral electrodes in a central portion of the column, and conduits directing an axial flow of radioactively contaminated air through the center of the column and pure air through the annular portion of the column about the electrodes. (AEC)

  17. Radioactivity: A Natural Phenomenon.

    ERIC Educational Resources Information Center

    Ronneau, C.

    1990-01-01

    Discussed is misinformation people have on the subject of radiation. The importance of comparing artificial source levels of radiation to natural levels is emphasized. Measurements of radioactivity, its consequences, and comparisons between the risks induced by radiation in the environment and from artificial sources are included. (KR)

  18. Viewer Makes Radioactivity "Visible"

    NASA Technical Reports Server (NTRS)

    Yin, L. I.

    1983-01-01

    Battery operated viewer demonstrates feasibility of generating threedimensional visible light simulations of objects that emit X-ray or gamma rays. Ray paths are traced for two pinhold positions to show location of reconstructed image. Images formed by pinholes are converted to intensified visible-light images. Applications range from radioactivity contamination surveys to monitoring radioisotope absorption in tumors.

  19. Disposal of radioactive waste

    NASA Astrophysics Data System (ADS)

    Van Dorp, Frits; Grogan, Helen; McCombie, Charles

    The aim of radioactive and non-radioactive waste management is to protect man and the environment from unacceptable risks. Protection criteria for both should therefore be based on similar considerations. From overall protection criteria, performance criteria for subsystems in waste management can be derived, for example for waste disposal. International developments in this field are summarized. A brief overview of radioactive waste sorts and disposal concepts is given. Currently being implemented are trench disposal and engineered near-surface facilities for low-level wastes. For low-and intermediate-level waste underground facilities are under construction. For high-level waste site selection and investigation is being carried out in several countries. In all countries with nuclear programmes, the predicted performance of waste disposal systems is being assessed in scenario and consequence analyses. The influences of variability and uncertainty of parameter values are increasingly being treated by probabilistic methods. Results of selected performance assessments show that radioactive waste disposal sites can be found and suitable repositories can be designed so that defined radioprotection limits are not exceeded.

  20. Radioactive Decay - An Analog.

    ERIC Educational Resources Information Center

    McGeachy, Frank

    1988-01-01

    Presents an analog of radioactive decay that allows the student to grasp the concept of half life and the exponential nature of the decay process. The analog is devised to use small, colored, plastic poker chips or counters. Provides the typical data and a graph which supports the analog. (YP)

  1. Radioactive Decay - An Analog.

    ERIC Educational Resources Information Center

    McGeachy, Frank

    1988-01-01

    Presents an analog of radioactive decay that allows the student to grasp the concept of half life and the exponential nature of the decay process. The analog is devised to use small, colored, plastic poker chips or counters. Provides the typical data and a graph which supports the analog. (YP)

  2. Detecting Illicit Radioactive Sources

    SciTech Connect

    McDonald, Joseph C.; Coursey, Bert; Carter, Michael

    2004-11-01

    Specialized instruments have been developed to detect the presence of illicit radioactive sources that may be used by terrorists in radiation dispersal devices, so-called ''dirty bombs'' or improvised nuclear devices. This article discusses developments in devices to detect and measure radiation.

  3. Fallout Radioactivity and Epiphytes.

    Treesearch

    H. T. Odum; George Ann Briscoe; C. B. Briscoe

    1970-01-01

    After relatively high levels of fallout retention were dicovered in the epiphytic mossy forest of the Luquillo Mountains durin 1962, a survey of the distribution of radioactivity in the rain forest system was made with beta counting of 1500 samples supplemented with gamma spectra. High levels, up to 4138 counts per minute per gram, were found mainly in or on green...

  4. Radioactivity and foods

    SciTech Connect

    Olszyna-Marzys, A.E. )

    1991-01-01

    The purpose of this article is to describe and contrast two relationships between radiation and food--on the one hand, beneficial preservation of food by controlled exposure to ionizing radiation; and, on the other, contamination of food by accidental incorporation of radioactive nuclides within the food itself. In food irradiation, electrons or electromagnetic radiation is used to destroy microorganisms and insects or prevent seed germination. The economic advantages and health benefits of sterilizing food in this manner are clear, and numerous studies have confirmed that under strictly controlled conditions no undersirable changes or induced radioactivity is produced in the irradiated food. An altogether different situation is presented by exposure of food animals and farming areas to radioactive materials, as occurred after the major Soviet nuclear reactor accident at Chenobyl. This article furnishes the basic information needed to understand the nature of food contamination associated with that event and describes the work of international organizations seeking to establish appropriate safe limits for levels of radioactivity in foods.

  5. Radioactivity: A Natural Phenomenon.

    ERIC Educational Resources Information Center

    Ronneau, C.

    1990-01-01

    Discussed is misinformation people have on the subject of radiation. The importance of comparing artificial source levels of radiation to natural levels is emphasized. Measurements of radioactivity, its consequences, and comparisons between the risks induced by radiation in the environment and from artificial sources are included. (KR)

  6. Production of selenium-72 and arsenic-72

    DOEpatents

    Phillips, Dennis R.

    1994-01-01

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

  7. Production of selenium-72 and arsenic-72

    DOEpatents

    Phillips, D.R.

    1994-12-06

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

  8. Production of selenium-72 and arsenic-72

    DOEpatents

    Phillips, Dennis R.

    1995-01-01

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

  9. REACTOR FUEL ELEMENTS TESTING CONTAINER

    DOEpatents

    Whitham, G.K.; Smith, R.R.

    1963-01-15

    This patent shows a method for detecting leaks in jacketed fuel elements. The element is placed in a sealed tank within a nuclear reactor, and, while the reactor operates, the element is sparged with gas. The gas is then led outside the reactor and monitored for radioactive Xe or Kr. (AEC)

  10. Environmental Radioactivity, Temperature, and Precipitation.

    ERIC Educational Resources Information Center

    Riland, Carson A.

    1996-01-01

    Reports that environmental radioactivity levels vary with temperature and precipitation and these effects are due to radon. Discusses the measurement of this environmental radioactivity and the theory behind it. (JRH)

  11. Environmental Radioactivity, Temperature, and Precipitation.

    ERIC Educational Resources Information Center

    Riland, Carson A.

    1996-01-01

    Reports that environmental radioactivity levels vary with temperature and precipitation and these effects are due to radon. Discusses the measurement of this environmental radioactivity and the theory behind it. (JRH)

  12. Background X-ray Spectrum of Radioactive Samples

    SciTech Connect

    Shannon Yee; Dawn E. Janney

    2008-02-01

    An energy-dispersive X-ray spectrometer (EDS) is commonly used with a scanning electron microscope (SEM) to analyze the elemental compositions and microstructures of a variety of samples. For example, the microstructures of nuclear fuels are commonly investigated with this technique. However, the radioactivity of some materials introduces additional X-rays that contribute to the EDS background spectrum. These X-rays are generally not accounted for in spectral analysis software, and can cause misleading results. X-rays from internal conversion [1], Bremsstrahlung [2] radiation associated with alpha ionizations and beta particle interactions [3], and gamma rays from radioactive decay can all elevate the background of radioactive materials.

  13. Radioactivity in fossils at the Hagerman Fossil Beds National Monument.

    PubMed

    Farmer, C Neal; Kathren, Ronald L; Christensen, Craig

    2008-08-01

    Since 1996, higher than background levels of naturally occurring radioactivity have been documented in both fossil and mineral deposits at Hagerman Fossil Beds National Monument in south-central Idaho. Radioactive fossil sites occur primarily within an elevation zone of 900-1000 m above sea level and are most commonly found associated with ancient river channels filled with sand. Fossils found in clay rich deposits do not exhibit discernable levels of radioactivity. Out of 300 randomly selected fossils, approximately three-fourths exhibit detectable levels of natural radioactivity ranging from 1 to 2 orders of magnitude above ambient background levels when surveyed with a portable hand held Geiger-Muller survey instrument. Mineral deposits in geologic strata also show above ambient background levels of radioactivity. Radiochemical lab analysis has documented the presence of numerous natural radioactive isotopes. It is postulated that ancient groundwater transported radioactive elements through sand bodies containing fossils which precipitated out of solution during the fossilization process. The elevated levels of natural radioactivity in fossils may require special precautions to ensure that exposures to personnel from stored or displayed items are kept as low as reasonably achievable (ALARA).

  14. Method for calcining radioactive wastes

    DOEpatents

    Bjorklund, William J.; McElroy, Jack L.; Mendel, John E.

    1979-01-01

    This invention relates to a method for the preparation of radioactive wastes in a low leachability form by calcining the radioactive waste on a fluidized bed of glass frit, removing the calcined waste to melter to form a homogeneous melt of the glass and the calcined waste, and then solidifying the melt to encapsulate the radioactive calcine in a glass matrix.

  15. Radioactive heat sources in the lunar interior.

    NASA Technical Reports Server (NTRS)

    Hays, J. F.

    1972-01-01

    Published models for the moon's thermal history typically imply present day central temperatures far too high to be consistent with the recently proposed lunar temperature profile of Sonett et al. (1971). Furthermore, chemical data on Apollo samples show that the moon is depleted relative to chondrites in volatile elements, and possibly enriched relative to chondrites in refractory elements. Additional thermal models have therefore been investigated in order to set upper limits on lunar radioactivity consistent with the proposed temperature distribution. For an initially cold, uniform moon, devoid of potassium, a maximum uranium content of 23 parts per billion is inferred.

  16. Effects of low arsenic concentration exposure on freshwater fish in the presence of fluvial biofilms.

    PubMed

    Tuulaikhuu, Baigal-Amar; Bonet, Berta; Guasch, Helena

    2016-02-15

    Arsenic (As) is a highly toxic element and its carcinogenic effect on living organisms is well known. However, predicting real effects in the environment requires an ecological approach since toxicity is influenced by many environmental and biological factors. The purpose of this paper was to evaluate if environmentally-realistic arsenic exposure causes toxicity to fish. An experiment with four different treatments (control (C), biofilm (B), arsenic (+As) and biofilm with arsenic (B+As)) was conducted and each one included sediment to enhance environmental realism, allowing the testing of the interactive effects of biofilm and arsenic on the toxicity to fish. Average arsenic exposure to Eastern mosquitofish (Gambusia holbrooki) was 40.5 ± 7.5 μg/L for +As treatment and 34.4 ± 1.4 μg/L for B+As treatment for 56 days. Fish were affected directly and indirectly by this low arsenic concentration since exposure did not only affect fish but also the function of periphytic biofilms. Arsenic effects on the superoxide dismutase (SOD) and glutathione reductase (GR) activities in the liver of mosquitofish were ameliorated in the presence of biofilms at the beginning of exposure (day 9). Moreover, fish weight gaining was only affected in the treatment without biofilm. After longer exposure (56 days), effects of exposure were clearly seen. Fish showed a marked increase in the catalase (CAT) activity in the liver but the interactive influence of biofilms was not further observed since the arsenic-affected biofilm had lost its role in water purification. Our results highlight the interest and application of incorporating some of the complexity of natural systems in ecotoxicology and support the use of criterion continuous concentration (CCC) for arsenic lower than 150 μg/L and closer to the water quality criteria to protect aquatic life recommended by the Canadian government which is 5 μg As/L.

  17. Monitoring the arsenic and iodine exposure of seaweed-eating North Ronaldsay sheep from the gestational and suckling periods to adulthood by using horns as a dietary archive.

    PubMed

    Caumette, Guilhem; Ouypornkochagorn, Sairoong; Scrimgeour, Charlie M; Raab, Andrea; Feldmann, Jörg

    2007-04-15

    Trace elements often accumulate in keratin-rich tissues. Hair, nails, and horns grow steadily but once formed are metabolically inactive and provide an archive of trace element exposure when analyzed in segments. Here we demonstrate the use of laser ablation ICP-MS for the high-resolution monitoring of trace elements in the horns of seaweed-eating sheep from North Ronaldsay, which live on grass only during lambing time. Due to this peculiar husbandry/dietary pattern and the fact that seaweed is rich in arsenic and iodine, we hoped to use iodine and arsenic as markers for seaweed ingestion. Cross sections and scans along the growing axis (representing the first 8-10 months of the sheep's life) revealed that these elements were not homogeneously distributed in the horn, with arsenic representing the amount of seaweed intake. The scans show the periods in which the lambs were fed on milk and grass and the change to seaweed ingestion with the successive replacement of milk with seaweed; this was supported by the carbon and nitrogen isotope signatures (delta13C and delta15N) of the horn and the arsenic speciation in the horn. The period of low arsenic accumulation in the horn had terrestrial isotope signatures and accumulated arsenic of mainly inorganic origin. The period of high arsenic accumulation was characterized by isotope signatures of marine origin, and the majority of accumulated arsenic in the horn was the main arsenosugar metabolite dimethylarsinic acid. Although we have investigated only four different horns of individual sheep, this study shows that arsenic is not significantly transported with milk. However, the high concentration of arsenic in the oldest part of the horn, which was formed in utero, points to a relatively high placental transport of arsenic while the ewe was eating seaweed. In contrast to arsenic, iodine is transported not only through milk ingestion but also through the placenta in large quantities.

  18. Elevated childhood exposure to arsenic despite reduced drinking water concentrations--A longitudinal cohort study in rural Bangladesh.

    PubMed

    Kippler, Maria; Skröder, Helena; Rahman, Syed Moshfiqur; Tofail, Fahmida; Vahter, Marie

    2016-01-01

    The aim of this study was to evaluate the massive efforts to lower water arsenic concentrations in Bangladesh. In our large mother-child cohort in rural Matlab, we measured the arsenic concentrations (and other elements) in drinking water and evaluated the actual exposure (urinary arsenic), from early gestation to 10 years of age (n=1017). Median drinking water arsenic decreased from 23 (2002-2003) to <2 μg/L (2013), and the fraction of wells exceeding the national standard (50 μg/L) decreased from 58 to 27%. Still, some children had higher water arsenic at 10 years than earlier. Installation of deeper wells (>50 m) explained much of the lower water arsenic concentrations, but increased the manganese concentrations. The highest manganese concentrations (~900 μg/L) appeared in 50-100 m wells. Low arsenic and manganese concentrations (17% of the children) occurred mainly in >100 m wells. The decrease in urinary arsenic concentrations over time was less apparent, from 82 to 58 μg/L, indicating remaining sources of exposure, probably through food (mean 133 μg/kg in rice). Despite decreased water arsenic concentrations in rural Bangladesh, the children still have elevated exposure, largely from food. Considering the known risks of severe health effects in children, additional mitigation strategies are needed. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Arsenic concentrations in soils impacted by dam failure of coal-ash pond in Zemianske Kostolany, Slovakia.

    PubMed

    Jurkovič, L'ubomír; Hiller, Edgar; Veselská, Veronika; Pet'ková, Katarína

    2011-04-01

    In this study, the concentrations of arsenic were determined in the soils around old coal-ash pond. The soils in the study area were severely contaminated with arsenic after dam failure of the coal-ash pond. The mean concentrations of arsenic in soils collected from three sampling depths of 0-20, 20-40 and >40 cm were 173, 155 and 426 μg/g, respectively, exceeding greatly the Dutch intervention threshold for this element. Arsenic concentrations were positively correlated with total iron and aluminium contents in the soils (r = 0.73, p < 0.001 and r = 0.72, p < 0.001, respectively), indicating that oxyhydroxides of iron and aluminium may control the distribution of arsenic in these soils. Ammonium nitrate extractant was used to mimic availability of arsenic for plant uptake from the soils. Between 0.05 and 6.21% of the total soil arsenic were extracted using a single extraction test and a significant positive correlation between soil leachate pH and arsenic extractability (r = 0.70, p < 0.01) was observed. This suggested that soil pH might play a role in the bioavailability of arsenic.

  20. Phytofiltration of arsenic from drinking water using arsenic-hyperaccumulating ferns.

    PubMed

    Huang, Jianwei W; Poynton, Charissa Y; Kochian, Leon V; Elless, Mark P

    2004-06-15

    Arsenic contamination of drinking water poses serious health risks to millions of people worldwide. Current technologies used to clean arsenic-contaminated water have significant drawbacks, such as high cost and generation of large volumes of toxic waste. In this study, we investigated the potential of using recently identified arsenic-hyperaccumulating ferns to remove arsenic from drinking water. Hydroponically cultivated, two arsenic-hyperaccumulating fern species (Pteris vittata and Pteris cretica cv. Mayii) and a nonaccumulating fern species (Nephrolepis exaltata) were suspended in water containing 73As-labeled arsenic with initial arsenic concentrations ranging from 20 to 500 microg L(-1). The efficiency of arsenic phytofiltration by these fern species was determined by continuously monitoring the depletion of 73As-labeled arsenic concentration in the water. With an initial water arsenic concentration of 200 microg L(-1), P. vittata reduced the arsenic concentration by 98.6% to 2.8 microg L(-1) in 24 h. When the initial water arsenic was 20 microg L(-1), P. vittata reduced the arsenic concentration to 7.2 microg L(-1) in 6 h and to 0.4 microg L(-1) in 24 h. At similar plant ages, both P. vittata and P. cretica had similar arsenic phytofiltration efficiency and were able to rapidly remove arsenic from water to achieve arsenic levels below the new drinking water limit of 10 microg L(-1). However, N. exaltata failed to reduce water arsenic to achieve the limit under the same experimental conditions. The significantly higher efficiency of arsenic phytofiltration by arsenic-hyperaccumulating fern species is associated with their ability to rapidly translocate absorbed arsenic from roots to shoots. The nonaccumulating fern N. exaltata was unable to translocate the absorbed arsenic to the shoots. Our results demonstrate that the arsenic-phytofiltration technique may provide the basis for a solar-powered hydroponic technique that enables small-scale cleanup of arsenic

  1. Microbial contributions to coupled arsenic and sulfur cycling in the acid-sulfide hot spring Champagne Pool, New Zealand.

    PubMed

    Hug, Katrin; Maher, William A; Stott, Matthew B; Krikowa, Frank; Foster, Simon; Moreau, John W

    2014-01-01

    Acid-sulfide hot springs are analogs of early Earth geothermal systems where microbial metal(loid) resistance likely first evolved. Arsenic is a metalloid enriched in the acid-sulfide hot spring Champagne Pool (Waiotapu, New Zealand). Arsenic speciation in Champagne Pool follows reaction paths not yet fully understood with respect to biotic contributions and coupling to biogeochemical sulfur cycling. Here we present quantitative arsenic speciation from Champagne Pool, finding arsenite dominant in the pool, rim and outflow channel (55-75% total arsenic), and dithio- and trithioarsenates ubiquitously present as 18-25% total arsenic. In the outflow channel, dimethylmonothioarsenate comprised ≤9% total arsenic, while on the outflow terrace thioarsenates were present at 55% total arsenic. We also quantified sulfide, thiosulfate, sulfate and elemental sulfur, finding sulfide and sulfate as major species in the pool and outflow terrace, respectively. Elemental sulfur concentration reached a maximum at the terrace. Phylogenetic analysis of 16S rRNA genes from metagenomic sequencing revealed the dominance of Sulfurihydrogenibium at all sites and an increased archaeal population at the rim and outflow channel. Several phylotypes were found closely related to known sulfur- and sulfide-oxidizers, as well as sulfur- and sulfate-reducers. Bioinformatic analysis revealed genes underpinning sulfur redox transformations, consistent with sulfur speciation data, and illustrating a microbial role in sulfur-dependent transformation of arsenite to thioarsenate. Metagenomic analysis also revealed genes encoding for arsenate reductase at all sites, reflecting the ubiquity of thioarsenate and a need for microbial arsenate resistance despite anoxic conditions. Absence of the arsenite oxidase gene, aio, at all sites suggests prioritization of arsenite detoxification over coupling to energy conservation. Finally, detection of methyl arsenic in the outflow channel, in conjunction with

  2. Microbial contributions to coupled arsenic and sulfur cycling in the acid-sulfide hot spring Champagne Pool, New Zealand

    PubMed Central

    Hug, Katrin; Maher, William A.; Stott, Matthew B.; Krikowa, Frank; Foster, Simon; Moreau, John W.

    2014-01-01

    Acid-sulfide hot springs are analogs of early Earth geothermal systems where microbial metal(loid) resistance likely first evolved. Arsenic is a metalloid enriched in the acid-sulfide hot spring Champagne Pool (Waiotapu, New Zealand). Arsenic speciation in Champagne Pool follows reaction paths not yet fully understood with respect to biotic contributions and coupling to biogeochemical sulfur cycling. Here we present quantitative arsenic speciation from Champagne Pool, finding arsenite dominant in the pool, rim and outflow channel (55–75% total arsenic), and dithio- and trithioarsenates ubiquitously present as 18–25% total arsenic. In the outflow channel, dimethylmonothioarsenate comprised ≤9% total arsenic, while on the outflow terrace thioarsenates were present at 55% total arsenic. We also quantified sulfide, thiosulfate, sulfate and elemental sulfur, finding sulfide and sulfate as major species in the pool and outflow terrace, respectively. Elemental sulfur concentration reached a maximum at the terrace. Phylogenetic analysis of 16S rRNA genes from metagenomic sequencing revealed the dominance of Sulfurihydrogenibium at all sites and an increased archaeal population at the rim and outflow channel. Several phylotypes were found closely related to known sulfur- and sulfide-oxidizers, as well as sulfur- and sulfate-reducers. Bioinformatic analysis revealed genes underpinning sulfur redox transformations, consistent with sulfur speciation data, and illustrating a microbial role in sulfur-dependent transformation of arsenite to thioarsenate. Metagenomic analysis also revealed genes encoding for arsenate reductase at all sites, reflecting the ubiquity of thioarsenate and a need for microbial arsenate resistance despite anoxic conditions. Absence of the arsenite oxidase gene, aio, at all sites suggests prioritization of arsenite detoxification over coupling to energy conservation. Finally, detection of methyl arsenic in the outflow channel, in conjunction with

  3. Arsenic encapsulation using Portland cement with ferrous sulfate/lime and Terra-Bond™ technologies - Microcharacterization and leaching studies.

    PubMed

    Randall, Paul M

    2012-03-15

    This work reports the results of an investigation on the treatment and encapsulation of arsenic-containing materials by Portland cement with ferrous sulfate and lime (PFL) and Terra-Bond™, a commercially available patented technology. The arsenic materials included: chromated copper arsenate (CCA)-treated wood materials; scorodite-rich mine tailings from the La Trinidad Mine in California; and a soil/smelter dust mixture from the Anaconda Superfund site spiked with monosodium methyl arsenate (MSMA) to simulate an organoarsenic soil material. SEM/EDS and XRD spectra of PFL treated samples showed similarity across all three waste materials while Terra-Bond treated samples showed predominance of elemental sulfur. SEM/EDS of PFL treated samples showed that calcium was imbedded in the structure while micrographs of Terra-Bond treated samples showed the appearance of an epoxy material on the surface. The epoxy material appears to be responsible for encapsulating and reducing the leachability of arsenic. XANES spectra for the PFL treatment of CCA-containing samples showed that arsenic has a predominant pentavalent form (As +5), and the PFL treatment process did not alter the arsenic oxidation state. But, distinct differences were observed for XANES spectra of untreated and PFL treated scorodite-rich mine tailing which changed the arsenic coordination structure from a mixture of As (+3/+5) to exclusively As (+5). Both S/S techniques reduced the amount of arsenic released in the leaching tests. Most cases show lower amounts of arsenic released from wastes treated by the Terra-Bond™ technique when compared to the PFL technique. The pH of the solution significantly affected the leachability, with the amount of arsenic released increasing with pH. Sequential extraction results indicate that sodium hydroxide was favorable in releasing arsenic in the mine tailings. This is due to ligand displacement reactions of hydroxyl ions with arsenic species and high pH conditions that

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

    EPA Science Inventory

    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...

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

    EPA Science Inventory

    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...

  6. International radioactive material recycling challenges

    SciTech Connect

    Greeves, John T.; Lieberman, James

    2007-07-01

    The paper explores current examples of successful International radioactive recycling programs and also explores operational regulatory and political challenges that need to be considered for expanding international recycling world-wide. Most countries regulations are fully consistent with the International Atomic Agency (IAEA) Code of Practice on the International Transboundary Movement of Radioactive Material and the IAEA Code of Conduct on the Safety and Security of Radioactive Sources. IAEA member States reported on the status of their efforts to control transboundary movement of radioactive material recently during the Joint Convention on the Safety of Spent Fuel management and on the Safety of Radioactive Waste Management meeting in May 2006. (authors)

  7. Process for decontaminating radioactive waste water using a ferrofluid and magnetic separation

    SciTech Connect

    Silver, G.L.

    1980-07-31

    The present invention provides a process for decontaminating radioactive waste water containing a radioactive element that forms a water-insoluble compound. This process includes the steps of forming the compound of the radioactive element, treating the resulting waste water with a ferrofluid, dispersing the ferrofluid, diluting the solids concentration of the resulting mixture with a coagulation initiator, such as ethyl alcohol or acetone, and collecting by use of a magnetic field, the resulting radioactive sludge. In a variation of the process, the steps involving the use of the coagulation initiator and the use of the ferrofluid are reversed.

  8. Enhanced coagulation for arsenic removal

    SciTech Connect

    Cheng, R.C.; Liang, S.; Wang, H.C.; Beuhler, M.D. )

    1994-09-01

    The possible use of enhanced coagulation for arsenic removal was examined at the facilities of a California utility in 1992 and 1993. The tests were conducted at bench, pilot, and demonstration scales, with two source waters. Alum and ferric chloride, with cationic polymer, were investigated at various influence arsenic concentrations. The investigators concluded that for the source waters tested, enhanced coagulation could be effective for arsenic removal and that less ferric chloride than alum, on a weight basis, is needed to achieve the same removal.

  9. Arsenic speciation and bioaccessibility in arsenic-contaminated soils: sequential extraction and mineralogical investigation.

    PubMed

    Kim, Eun Jung; Yoo, Jong-Chan; Baek, Kitae

    2014-03-01

    In this study, a combination of sequential extraction and mineralogical investigation by X-ray diffraction and X-ray photoelectron spectroscopy was employed in order to evaluate arsenic solid-state speciation and bioaccessibility in soils highly contaminated with arsenic from mining and smelting. Combination of these techniques indicated that iron oxides and the weathering products of sulfide minerals played an important role in regulating the arsenic retention in the soils. Higher bioaccessibility of arsenic was observed in the following order; i) arsenic bound to amorphous iron oxides (smelter-2), ii) arsenic associated with crystalline iron oxides and arsenic sulfide phase (smelter-1), and iii) arsenic associated with the weathering products of arsenic sulfide minerals, such as scorodite, orpiment, jarosite, and pyrite (mine). Even though the bioaccessibility of arsenic was very low in the mine soil, its environmental impact could be significant due to its high arsenic concentration and mobility. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Arsenic behavior in newly drilled wells

    USGS Publications Warehouse

    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 <1 to 171 ??g/l. The arsenic concentration in groundwater depended on the amount of arsenic in aquifer rocks, and as well decreased with increasing depth. Over 90% of arsenic existed in the form of As(III), implying that the groundwater systems were in the reduced condition. The results such as high ferrous 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.

  11. PROCESSING OF RADIOACTIVE WASTE

    DOEpatents

    Johnson, B.M. Jr.; Barton, G.B.

    1961-11-14

    A process for treating radioactive waste solutions prior to disposal is described. A water-soluble phosphate, borate, and/or silicate is added. The solution is sprayed with steam into a space heated from 325 to 400 deg C whereby a powder is formed. The powder is melted and calcined at from 800 to 1000 deg C. Water vapor and gaseous products are separated from the glass formed. (AEC)

  12. Radioactive waste storage issues

    SciTech Connect

    Kunz, Daniel E.

    1994-08-15

    In the United States we generate greater than 500 million tons of toxic waste per year which pose a threat to human health and the environment. Some of the most toxic of these wastes are those that are radioactively contaminated. This thesis explores the need for permanent disposal facilities to isolate radioactive waste materials that are being stored temporarily, and therefore potentially unsafely, at generating facilities. Because of current controversies involving the interstate transfer of toxic waste, more states are restricting the flow of wastes into - their borders with the resultant outcome of requiring the management (storage and disposal) of wastes generated solely within a state`s boundary to remain there. The purpose of this project is to study nuclear waste storage issues and public perceptions of this important matter. Temporary storage at generating facilities is a cause for safety concerns and underscores, the need for the opening of permanent disposal sites. Political controversies and public concern are forcing states to look within their own borders to find solutions to this difficult problem. Permanent disposal or retrievable storage for radioactive waste may become a necessity in the near future in Colorado. Suitable areas that could support - a nuclear storage/disposal site need to be explored to make certain the health, safety and environment of our citizens now, and that of future generations, will be protected.

  13. Radioactive deposits of Nevada

    USGS Publications Warehouse

    Lovering, T.G.

    1954-01-01

    Thirty-five occurrences of radioactive rocks had been reported from Nevada prior to 1952. Twenty-five of these had been investigated by personnel of the U. S. Geological Surveyor of the U. S. Atomic Energy Commission. Of those investigated, uranium minerals were identified at 13 sites; two sites contained a thorium mineral (monazite); the source of radioactivity on nine properties was not ascertained, and one showed no abnormal radioactivity. Of the other reported occurrences, one is said to contain uraniferous hydrocarbons and nine are placers containing thorian monazite. Pitchblende occurs at two localities, the East Walker River area, and the Stalin's Present prospect, where it is sparsely disseminated in tabular bodies cutting granitic rocks. Other uranium minerals found in the state include: carnotite, tyuyamunite, autunite, torbernite, gummite, uranophane, kasolite, and an unidentified mineral which may be dumontite. Monazite is the only thorium mineral of possible economic importance that has been reported. From an economic standpoint, only four of the properties examined showed reserves of uranium ore in 1952; these are: the Green Monster mine, which shipped 5 tons of ore to Marysvale, Utah, during 1951; the Majuba Hill mine; the Stalin's Present prospect; and the West Willys claim in the Washington district. No estimate has been made of thorium reserves and no commercial deposits of thorium are known.

  14. Radioactive deposits of Nevada

    USGS Publications Warehouse

    Lovering, T.G.

    1953-01-01

    Thirty-five occurrences of radioactive rocks had been reported from Nevada prior to 1952. Twenty-five of these had been investigated by the U. S. Geological Survey and the U. S. Atomic Energy Commission. Of those investigated, uranium minerals were identified in 13; two contained a thorium mineral (monazite); the source of radioactivity on 7 properties was not ascertained; and one showed no abnormal radioactivity. Of the other reported occurrences, one is said to contain uraniferous hydrocarbons and 9 are placers containing thorian monazite. Pitchblende occurs at two localities; the East Walker River area, and the Stalin's Present prospect, where it is sparsely disseminated in tabular bodies cutting granitic rocks. Other uranium minerals found in the state include: carnotite, tyuyamunite, autunite, torbernite, gummite, uranophane, kasolite, and an unidentified mineral which may be dumontit. Monazite is the only thorium mineral of possible economic importance that has been reported. From an economic standpoint 9 only 4 of the properties examined showed reserves of uranium ore in 1952; these are: the Green Monster mine, which shipped 5 tons of ore to Marysvale, Utah, during 1951, the Majuba Hill mine, the Stalin's Present prospect, and the West Willys claim in the Washington district. Reserves of ore grade are small on all of these properties and probably cannot be developed commercially unless an ore-buying station is set up nearby. No estimate has been made of thorium reserves and no commercial deposits of thorium are known.

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

    SciTech Connect

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

    2008-10-01

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

  16. Construction of a Modular Arsenic-Resistance Operon in E. coli and the Production of Arsenic Nanoparticles

    PubMed Central

    Edmundson, Matthew Charles; Horsfall, Louise

    2015-01-01

    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 Escherichia 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 have also investigated 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. PMID:26539432

  17. Construction of a Modular Arsenic-Resistance Operon in E. coli and the Production of Arsenic Nanoparticles.

    PubMed

    Edmundson, Matthew Charles; Horsfall, Louise

    2015-01-01

    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 Escherichia 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 have also investigated 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.

  18. Effects of arsenic on adipocyte metabolism: Is arsenic an obesogen?

    PubMed

    Ceja-Galicia, Zeltzin A; Daniel, Alberto; Salazar, Ana María; Pánico, Pablo; Ostrosky-Wegman, Patricia; Díaz-Villaseñor, Andrea

    2017-09-05

    The environmental obesogen model proposes that in addition to a high-calorie diet and diminished physical activity, other factors such as environmental pollutants and chemicals are involved in the development of obesity. Although arsenic has been recognized as a risk factor for Type 2 Diabetes with a specific mechanism, it is still uncertain whether arsenic is also an obesogen. The impairment of white adipose tissue (WAT) metabolism is crucial in the onset of obesity, and distinct studies have evaluated the effects of arsenic on it, however only in some of them for obesity-related purposes. Thus, the known effects of arsenic on WAT/adipocytes were integrated based on the diverse metabolic and physiological processes that occur in WAT and are altered in obesity, specifically: adipocyte growth, adipokine secretion, lipid metabolism, and glucose metabolism. The currently available information suggests that arsenic can negatively affect WAT metabolism, resulting in arsenic being a potential obesogen. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. The heaviest elements

    SciTech Connect

    Hoffman, D.C. Lawrence Berkeley Lab., CA )

    1994-05-02

    How long does an atom need to exist before it's possible to do any meaningful chemistry on it Is it possible to learn anything at all about the reactions of an element for which no more than a few dozen atoms have ever existed simultaneously These are some of the questions colleagues in a few laboratories worldwide attempt to answer as they investigate the chemistry of the heaviest elements--elements produced one atom at a time in accelerators by bombarding radioactive targets with high-intensity beams of heavy ions. All of these elements spontaneously decay; the most stable of them have half-lives of only a few minutes, some that are less stable exist for only milliseconds. So far, no chemical studies have been performed on elements whose longest lived isotopes last only milliseconds because the difficulties of doing chemistry on this time scale under highly radioactive conditions are enormous. Over the past 10 years, however, nuclear chemists have developed new techniques or adapted existing ones to begin to probe the chemical properties of those very heavy elements that have half-lives in the range of seconds to minutes. Although the classic experiments are now nearly 40 years old, they are worth describing, as they were the first of their kind and illustrate many of the techniques that are still used and essential in studying these very short-lived, radioactive elements.

  20. Arsenic in Norway lobster (Nephrophs norvegicus L. ) from Kvarneric Bay - Northeastern Adriatic

    SciTech Connect

    Sekulic, B. ); Sapunar, J.; Bazulic, D. )

    1993-09-01

    Arsenic is of concern as environmental pollutant because it is a ubiquitous element known to give rise to adverse human health effects ranging from minor disorders to cancer and acute death. Arsenic occurrence in the environment depends on such human activities as coal burning, use of pesticides, glass industry, electric application, veterinary medicine, etc. It has long been known that marine fishery products may contain high levels of arsenic. Fortunately, mainly in the organic, non-toxic form, with the average proportion of organic form in total arsenic between 71-79% and 50-97%. According to Lawrence et al., arsenic in marine fish was identified as arsenobetaine and, in shrimp only, arsenocholine. This paper examines the levels of total arsenic in the sample of the muscle and hepatopancreas of female and male Norway lobster, Nephrophs norvegicus L. from the area of Kvarneric Bay, Northeastern Adriatic (Croatia). The average values of arsenic in muscle from female and male lobster were 13.26 mg (kg and 14.20. mg/kg), respectively. In hepatopancreas the values were 17.12 mg/kg and 13.34 mg/kg for female and male, respectively. 11 refs., 1 fig., 1 tab.

  1. Arsenic compounds: revived ancient remedies in the fight against human malignancies.

    PubMed

    Liu, Jian-Xiang; Zhou, Guang-Biao; Chen, Sai-Juan; Chen, Zhu

    2012-04-01

    Arsenic, the 20th most abundant element in the earth crust, is one of the oldest drugs in the world. It was used in the 18th century in treating hematopoietic malignancies, discarded in 1950s in favor of chemotherapeutic agents (busulphan and others), and was revived in the 1970s due to its dramatic efficacy on acute promyelocytic leukemia (APL) driven by the t(15;17) translocation-generated PML-RARα fusion. Arsenic represents the most potent single agent for APL, and achieves a five-year overall survival of 90% in APL patients when combined with all-trans retinoic acid (ATRA) and chemotherapy (daunorubicin and cytarabine), turning this disease from highly fatal to highly curable. Arsenic triggers sumoylation/ubiquitination and proteasomal degradation of PML-RARα via directly binding to the C3HC4 zinc finger motif in the RBCC domain of the PML moiety and induction of its homodimerization/multimerization and interaction with the SUMO E2 conjugase Ubc9. Because of its multiplicity of targets and complex mechanisms of action, arsenic is widely tested in combination with other agents in a variety of malignancies. Other arsenic containing recipes including oral formulations and organic arsenicals are being developed and tested, and progress in these areas will definitely expand the use of arsenicals in other malignant diseases. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Variations of arsenic species content in edible Boletus badius growing at polluted sites over four years.

    PubMed

    Mleczek, Mirosław; Niedzielski, Przemysław; Rzymski, Piotr; Siwulski, Marek; Gąsecka, Monika; Kozak, Lidia

    2016-07-02

    The content of arsenic (As) in mushrooms can vary depending on the concentration level of this metalloid in the soil/substrate. The present study evaluated the content of arsenic in Boletus badius fruiting bodies collected from polluted and non-polluted sites in relation to the content of this element in overgrown substrate. It was found that mushrooms from the arsenic-polluted sites contained mean concentrations from 49 to 450 mg As kg(-1) dry matter (d.m.), with the greatest content found for specimens growing in close proximity of sludge deposits (490±20 mg As kg(-1)d.m.). The mean content of total arsenic in mushrooms from clean sites ranged from 0.03 to 0.37 mg kg(-1) It was found that B. badius could tolerate arsenic in soil substrate at concentrations of up to 2500 mg kg(-1), at least. In different years of investigation, shifts in particular arsenic forms, as well as a general increase in the accumulation of organic arsenic content, were observed. The results of this study clearly indicate that B. badius should not be collected for culinary purposes from any sites that may be affected by pollution.

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

    NASA Astrophysics Data System (ADS)

    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

  4. New Arsenic Cross Section Calculations

    SciTech Connect

    Kawano, Toshihiko

    2015-03-04

    This report presents calculations for the new arsenic cross section. Cross sections for 73,74,75 As above the resonance range were calculated with a newly developed Hauser-Feshbach code, CoH3.

  5. [Arsenic as an environmental problem].

    PubMed

    Jensen, K

    2000-12-04

    Chronic exposure to arsenic through drinking water is known in different continents. Arsenic compounds from disintegrating rock may be solubilized after reduction by organic material, and harmful concentrations of arsenic may be found in surface water as well as in water from drilled wells. Because of well drilling since the sixties in the Ganges delta numerous millions of people have been exposed to toxic amounts, and hundreds of thousands demonstrate signs of chronic poisoning. A changed water technology and chemical precipitation of arsenic in the drinking water can reduce the size of the problem, but the late sequelae i.e. malignant disease are incalculable. Indications for antidotal treatment of exposed individuals have not yet been outlined.

  6. Groundwater arsenic contamination throughout China.

    PubMed

    Rodríguez-Lado, Luis; Sun, Guifan; Berg, Michael; Zhang, Qiang; Xue, Hanbin; Zheng, Quanmei; Johnson, C Annette

    2013-08-23

    Arsenic-contaminated groundwater used for drinking in China is a health threat that was first recognized in the 1960s. However, because of the sheer size of the country, millions of groundwater wells remain to be tested in order to determine the magnitude of the problem. We developed a statistical risk model that classifies safe and unsafe areas with respect to geogenic arsenic contamination in China, using the threshold of 10 micrograms per liter, the World Health Organization guideline and current Chinese standard for drinking water. We estimate that 19.6 million people are at risk of being affected by the consumption of arsenic-contaminated groundwater. Although the results must be confirmed with additional field measurements, our risk model identifies numerous arsenic-affected areas and highlights the potential magnitude of this health threat in China.

  7. THE PATHWAY OF ARSENIC METABLISM

    EPA Science Inventory

    The Pathway of Arsenic Methylation

    David J. Thomas, Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

    Understanding ...

  8. ASSESSMENT OF RADIOACTIVE AND NON-RADIOACTIVE CONTAMINANTS FOUND IN LOW LEVEL RADIOACTIVE WASTE STREAMS

    SciTech Connect

    R.H. Little, P.R. Maul, J.S.S. Penfoldag

    2003-02-27

    This paper describes and presents the findings from two studies undertaken for the European Commission to assess the long-term impact upon the environment and human health of non-radioactive contaminants found in various low level radioactive waste streams. The initial study investigated the application of safety assessment approaches developed for radioactive contaminants to the assessment of nonradioactive contaminants in low level radioactive waste. It demonstrated how disposal limits could be derived for a range of non-radioactive contaminants and generic disposal facilities. The follow-up study used the same approach but undertook more detailed, disposal system specific calculations, assessing the impacts of both the non-radioactive and radioactive contaminants. The calculations undertaken indicated that it is prudent to consider non-radioactive, as well as radioactive contaminants, when assessing the impacts of low level radioactive waste disposal. For some waste streams with relatively low concentrations of radionuclides, the potential post-closure disposal impacts from non-radioactive contaminants can be comparable with the potential radiological impacts. For such waste streams there is therefore an added incentive to explore options for recycling the materials involved wherever possible.

  9. Determination of Trace Elements in Nickel Base Alloys by Atomic Absorption Spectrophotometry.

    DTIC Science & Technology

    elements such as silver (Ag), bismuth (Bi), cadmium (Cd), lead ( Pb ), phosphorus (P), and arsenic (As) in nickel alloys such as Udimet 500 without interference of other constituent elements. (Author)

  10. Arsenic Mobilization Influenced By Iron Reduction And Sulfidogenesis Under Dynamic Flow

    NASA Astrophysics Data System (ADS)

    Kocar, B. D.; Stewart, B. D.; Herbel, M.; Fendorf, S.

    2004-12-01

    Sulfidogenesis and iron reduction are ubiquitous processes that occur in a variety of anoxic subsurface and surface environments, which profoundly impact the cycling of arsenic. Of the iron (hydr)oxides, ferrihydrite possesses one of the highest capacities to retain arsenic, and is globally distributed within soils and sediments. Upon dissimilatory iron reduction, ferrihydrite may transform to lower surface area minerals, such as goethite and magnetite, which decreases arsenic retention, thus enhancing its transport. Here we examine how arsenic retained on ferrihydrite is mobilized under dynamic flow in the presence of Sulfurosprillum barnesii strain SES-3, a bacteria capable of reducing both As(V) and Fe(III). Ferrihydrite coated sands, loaded with 150 mg kg-1 As(V), were inoculated with S. barnesii, packed into a column and reacted with a synthetic groundwater solution. Within several days after initiation of flow, the concentration of arsenic in the column effluent increased dramatically coincident with the mineralogical transformation of ferrihydrite and As(V) reduction to As(III). Following the initial pulse of arsenic, effluent concentration then declined to less than 10 μ M. Thus, arsenic release into the aqueous phase is contingent upon the incongruent reduction of As(V) and Fe(III) as mediated by biological activity. Reaction of abiotically or biotically generated dissolved sulfide with iron (hydr)oxides may have a dramatic influence on the fate of arsenic within surface and subsurface environments. Accordingly, we examined the reaction of dissolved bisulfide and iron (hydr)oxide complexed with arsenic in both batch and column systems. Low ratios of sulfide to iron in batch reaction systems result in the formation of elemental sulfur and concomitant arsenic release from the iron (hydr)oxide surface. High sulfide to iron ratios, in contrast, appear to favor the formation of iron and arsenic sulfides. Our findings demonstrate that iron (hydr)oxides may

  11. Human biomonitoring of arsenic and antimony in case of an elevated geogenic exposure.

    PubMed Central

    Gebel, T W; Suchenwirth, R H; Bolten, C; Dunkelberg, H H

    1998-01-01

    Part of the northern Palatinate region in Germany is characterized by elevated levels of arsenic and antimony in the soil due to the presence of ore sources and former mining activities. In a biomonitoring study, 218 residents were investigated for a putative increased intake of these elements. Seventy-six nonexposed subjects in a rural region in south lower Saxony were chosen as the reference group. Urine and scalp hair samples were obtained as surrogates to determine the internal exposures to arsenic and antimony. The analyses were performed using graphite furnace atomic absorption spectrometry except for arsenic in urine, which was determined by the hydride technique. This method does not detect organoarsenicals from seafood, which are not toxicologically relevant. In the northern Palatinate subjects, slightly elevated arsenic contents in urine and scalp hair (presumably not hazardous) could be correlated with an increased arsenic content in the soil. On the other hand, the results did not show a correlation between the antimony contents in the soil of the housing area and those in urine and hair. Except for antimony in scalp hair, age tended to be associated with internal exposures to arsenic and antimony in both study groups. Consumption of seafood had a slight impact on the level of urinary arsenic, which is indicative of the presence of low quantities of inorganic arsenicals and dimethylarsinic acid in seafood. The arsenic and antimony contents in scalp hair were positively correlated with the 24-hr arsenic excretion in urine. However, antimony in scalp hair was not correlated with seafood consumption as was arsenic in scalp hair and in urine. This indicated the existence of unidentified common pathways of exposure contributing to the alimentary body burden. Short time peaks in the 24-hr excretion of arsenic in urine, which could not be assigned to a high consumption of seafood, were detected for six study participants. This suggests that additional factors

  12. Radioactivity of the moon, planets, and meteorites

    NASA Technical Reports Server (NTRS)

    Surkou, Y. A.; Fedoseyev, G. A.

    1977-01-01

    Analytical data is summarized for the content of natural radioactive elements in meteorites, eruptive terrestrial rocks, and also in lunar samples returned by Apollo missions and the Luna series of automatic stations. The K-U systematics of samples analyzed in the laboratory are combined with data for orbital gamma-ray measurements for Mars (Mars 5) and with the results of direct gamma-ray measurements of the surface of Venus by the Venera 8 lander. Using information about the radioactivity of solar system bodies and evaluations of the content of K, U, and Th in the terrestrial planets, we examine certain aspects of the evolution of material in the protoplanetary gas-dust cloud and then in the planets of the solar system.

  13. Nuclear astrophysics with radioactive ions at FAIR

    NASA Astrophysics Data System (ADS)

    Reifarth, R.; Altstadt, S.; Göbel, K.; Heftrich, T.; Heil, M.; Koloczek, A.; Langer, C.; Plag, R.; Pohl, M.; Sonnabend, K.; Weigand, M.; Adachi, T.; Aksouh, F.; Al-Khalili, J.; AlGarawi, M.; AlGhamdi, S.; Alkhazov, G.; Alkhomashi, N.; Alvarez-Pol, H.; Alvarez-Rodriguez, R.; Andreev, V.; Andrei, B.; Atar, L.; Aumann, T.; Avdeichikov, V.; Bacri, C.; Bagchi, S.; Barbieri, C.; Beceiro, S.; Beck, C.; Beinrucker, C.; Belier, G.; Bemmerer, D.; Bendel, M.; Benlliure, J.; Benzoni, G.; Berjillos, R.; Bertini, D.; Bertulani, C.; Bishop, S.; Blasi, N.; Bloch, T.; Blumenfeld, Y.; Bonaccorso, A.; Boretzky, K.; Botvina, A.; Boudard, A.; Boutachkov, P.; Boztosun, I.; Bracco, A.; Brambilla, S.; Briz Monago, J.; Caamano, M.; Caesar, C.; Camera, F.; Casarejos, E.; Catford, W.; Cederkall, J.; Cederwall, B.; Chartier, M.; Chatillon, A.; Cherciu, M.; Chulkov, L.; Coleman-Smith, P.; Cortina-Gil, D.; Crespi, F.; Crespo, R.; Cresswell, J.; Csatlós, M.; Déchery, F.; Davids, B.; Davinson, T.; Derya, V.; Detistov, P.; Diaz Fernandez, P.; DiJulio, D.; Dmitry, S.; Doré, D.; Dueñas, J.; Dupont, E.; Egelhof, P.; Egorova, I.; Elekes, Z.; Enders, J.; Endres, J.; Ershov, S.; Ershova, O.; Fernandez-Dominguez, B.; Fetisov, A.; Fiori, E.; Fomichev, A.; Fonseca, M.; Fraile, L.; Freer, M.; Friese, J.; Borge, M. G.; Galaviz Redondo, D.; Gannon, S.; Garg, U.; Gasparic, I.; Gasques, L.; Gastineau, B.; Geissel, H.; Gernhäuser, R.; Ghosh, T.; Gilbert, M.; Glorius, J.; Golubev, P.; Gorshkov, A.; Gourishetty, A.; Grigorenko, L.; Gulyas, J.; Haiduc, M.; Hammache, F.; Harakeh, M.; Hass, M.; Heine, M.; Hennig, A.; Henriques, A.; Herzberg, R.; Holl, M.; Ignatov, A.; Ignatyuk, A.; Ilieva, S.; Ivanov, M.; Iwasa, N.; Jakobsson, B.; Johansson, H.; Jonson, B.; Joshi, P.; Junghans, A.; Jurado, B.; Körner, G.; Kalantar, N.; Kanungo, R.; Kelic-Heil, A.; Kezzar, K.; Khan, E.; Khanzadeev, A.; Kiselev, O.; Kogimtzis, M.; Körper, D.; Kräckmann, S.; Kröll, T.; Krücken, R.; Krasznahorkay, A.; Kratz, J.; Kresan, D.; Krings, T.; Krumbholz, A.; Krupko, S.; Kulessa, R.; Kumar, S.; Kurz, N.; Kuzmin, E.; Labiche, M.; Langanke, K.; Lazarus, I.; Le Bleis, T.; Lederer, C.; Lemasson, A.; Lemmon, R.; Liberati, V.; Litvinov, Y.; Löher, B.; Lopez Herraiz, J.; Münzenberg, G.; Machado, J.; Maev, E.; Mahata, K.; Mancusi, D.; Marganiec, J.; Martinez Perez, M.; Marusov, V.; Mengoni, D.; Million, B.; Morcelle, V.; Moreno, O.; Movsesyan, A.; Nacher, E.; Najafi, M.; Nakamura, T.; Naqvi, F.; Nikolski, E.; Nilsson, T.; Nociforo, C.; Nolan, P.; Novatsky, B.; Nyman, G.; Ornelas, A.; Palit, R.; Pandit, S.; Panin, V.; Paradela, C.; Parkar, V.; Paschalis, S.; Pawłowski, P.; Perea, A.; Pereira, J.; Petrache, C.; Petri, M.; Pickstone, S.; Pietralla, N.; Pietri, S.; Pivovarov, Y.; Potlog, P.; Prokofiev, A.; Rastrepina, G.; Rauscher, T.; Ribeiro, G.; Ricciardi, M.; Richter, A.; Rigollet, C.; Riisager, K.; Rios, A.; Ritter, C.; Rodriguez Frutos, T.; Rodriguez Vignote, J.; Röder, M.; Romig, C.; Rossi, D.; Roussel-Chomaz, P.; Rout, P.; Roy, S.; Söderström, P.; Saha Sarkar, M.; Sakuta, S.; Salsac, M.; Sampson, J.; Sanchez, J.; Rio Saez, del; Sanchez Rosado, J.; Sanjari, S.; Sarriguren, P.; Sauerwein, A.; Savran, D.; Scheidenberger, C.; Scheit, H.; Schmidt, S.; Schmitt, C.; Schnorrenberger, L.; Schrock, P.; Schwengner, R.; Seddon, D.; Sherrill, B.; Shrivastava, A.; Sidorchuk, S.; Silva, J.; Simon, H.; Simpson, E.; Singh, P.; Slobodan, D.; Sohler, D.; Spieker, M.; Stach, D.; Stan, E.; Stanoiu, M.; Stepantsov, S.; Stevenson, P.; Strieder, F.; Stuhl, L.; Suda, T.; Sümmerer, K.; Streicher, B.; Taieb, J.; Takechi, M.; Tanihata, I.; Taylor, J.; Tengblad, O.; Ter-Akopian, G.; Terashima, S.; Teubig, P.; Thies, R.; Thoennessen, M.; Thomas, T.; Thornhill, J.; Thungstrom, G.; Timar, J.; Togano, Y.; Tomohiro, U.; Tornyi, T.; Tostevin, J.; Townsley, C.; Trautmann, W.; Trivedi, T.; Typel, S.; Uberseder, E.; Udias, J.; Uesaka, T.; Uvarov, L.; Vajta, Z.; Velho, P.; Vikhrov, V.; Volknandt, M.; Volkov, V.; von Neumann-Cosel, P.; von Schmid, M.; Wagner, A.; Wamers, F.; Weick, H.; Wells, D.; Westerberg, L.; Wieland, O.; Wiescher, M.; Wimmer, C.; Wimmer, K.; Winfield, J. S.; Winkel, M.; Woods, P.; Wyss, R.; Yakorev, D.; Yavor, M.; Zamora Cardona, J.; Zartova, I.; Zerguerras, T.; Zgura, M.; Zhdanov, A.; Zhukov, M.; Zieblinski, M.; Zilges, A.; Zuber, K.

    2016-01-01

    The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process, β-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes.

  14. Geochemistry and migration of anthropogenic arsenic emissions in Yara Siilinjärvi industrial site, Finland

    NASA Astrophysics Data System (ADS)

    Turunen, Kaisa; Backnäs, Soile; Pasanen, Antti

    2013-04-01

    Arsenic is a problematic element due to its relatively high mobility over a wide range of redox-conditions and its toxicity to humans, animals and plants. In extractive and industrial minerals arsenic is a common element and cannot be eluded in mining and quarrying activities. Therefore, mining and industrial activities are one of the most serious arsenic polluters at local scale. In assessing environmental effects, it is important to compare anthropogenic arsenic load to geological background. The aim of this study was to characterize environmental effects and risks of the arsenic bearing calcinate tailings to the surrounding environment. Yara Finland industrial site in Siilinjärvi, Eastern Finland produces mainly fertilizers and phosphoric acid, but also 250 000 t/a iron calcinate is recovered as by-product at the sulphuric acid plant. The tailings area is located about 200 m from Lake Kuuslahti and surrounded by double ditches collecting runoff and seepage waters to seepage ponds. Some seepage water migrates to a bedrock fracture zone under the tailings area and contaminant transport from the fracture zone is controlled by pumping the water back to seepage ponds. The arsenic content (500 mg/kg) of the calcinate tailings is very high considering that the natural arsenic concentrations of the local bedrock and soil are low (<2 mg/kg). A total of 55 soil and sediment samples were analyzed for hot aqua regia, ammonium oxalate and acetate extractable arsenic representing total, chemically adsorbed and bioavailable fractions. In addition 14 water samples were analyzed for total and soluble metal and metalloid concentrations, anions, DOC, TOC, pH, redox and alkalinity. The metal speciation in surface and ground waters was modeled by PhreeqC. According to the results main arsenic pathways from the tailings to environment and into the Lake Kuuslahti are by dust and surface runoff. Close to the tailings arsenic concentrations are high and exceed the Finnish threshold

  15. Arsenic removal by ferric chloride

    SciTech Connect

    Hering, J.G.; Chen, P.Y.; Wilkie, J.A.; Elimelech, M.; Liang, S.

    1996-04-01

    Bench-scale studies were conducted in model freshwater systems to investigate how various parameters affected arsenic removal during coagulation with ferric chloride and arsenic adsorption onto preformed hydrous ferric oxide. Parameters included arsenic oxidation state and initial concentration, coagulant dosage or adsorbent concentration, pH, and the presence of co-occurring inorganic solutes. Comparison of coagulation and adsorption experiments and of experimental results with predictions based on surface complexation modeling demonstrated that adsorption is an important (though not the sole) mechanism governing arsenic removal during coagulation. Under comparable conditions, better removal was observed with arsenic(V) [As(V)] than with arsenic(III) [As(III)] in both coagulation and adsorption experiments. Below neutral pH values, As(III) removal-adsorption was significantly decreased in the presence of sulfate, whereas only a slight decrease in As(V) removal-adsorption was observed. At high pH, removal-adsorption of As(V) was increased in the presence of calcium. Removal of As(V) during coagulation with ferric chloride is both more efficient and less sensitive than that of As(III) to variations in source water composition.

  16. Radioactive nanoparticles and their main applications: recent advances.

    PubMed

    Kharisov, Boris I; Kharissova, Oxana V; Berdonosov, Sergei S

    2014-01-01

    Selected nanoparticles and nanocomposites on the basis of radioactive elements are reviewed. Isotopes of metallic gold, iodine and technetium salts, CeO2 and other lanthanide and actinide compounds, as well as several p- (P, C, F, Te) and d- (Fe, Co, Cu, Cd, Zn) elements form most common radioactive nanoparticles. Methods for their fabrication, including dopation with radionuclides and neutron/proton/deuteron activation, are discussed. These nanocomposites possess a series of useful applications, in particular in biology and medicine, including cancer therapeutics, drug delivery systems and radiotracers, as well as in the studies of several catalytic processes and materials structure.

  17. Industrial-Scale Processes For Stabilizing Radioactively Contaminated Mercury Wastes

    SciTech Connect

    Broderick, T. E.; Grondin, R.

    2003-02-24

    This paper describes two industrial-scaled processes now being used to treat two problematic mercury waste categories: elemental mercury contaminated with radionuclides and radioactive solid wastes containing greater than 260-ppm mercury. The stabilization processes were developed by ADA Technologies, Inc., an environmental control and process development company in Littleton, Colorado. Perma-Fix Environmental Services has licensed the liquid elemental mercury stabilization process to treat radioactive mercury from Los Alamos National Laboratory and other DOE sites. ADA and Perma-Fix also cooperated to apply the >260-ppm mercury treatment technology to a storm sewer sediment waste collected from the Y-12 complex in Oak Ridge, TN.

  18. Arsenic Toxicity in Male Reproduction and Development

    PubMed Central

    Kim, Yoon-Jae; Kim, Jong-Min

    2015-01-01

    Arsenic is a toxic metalloid that exists ubiquitously in the environment, and affects global health problems due to its carcinogenicity. In most populations, the main source of arsenic exposure is the drinking water. In drinking water, chronic exposure to arsenic is associated with increased risks of various cancers including those of skin, lung, bladder, and liver, as well as numerous other non-cancer diseases including gastrointestinal and cardiovascular diseases, diabetes, and neurologic and cognitive problems. Recent emerging evidences suggest that arsenic exposure affects the reproductive and developmental toxicity. Prenatal exposure to inorganic arsenic causes adverse pregnancy outcomes and children’s health problems. Some epidemiological studies have reported that arsenic exposure induces premature delivery, spontaneous abortion, and stillbirth. In animal studies, inorganic arsenic also causes fetal malformation, growth retardation, and fetal death. These toxic effects depend on dose, route and gestation periods of arsenic exposure. In males, inorganic arsenic causes reproductive dysfunctions including reductions of the testis weights, accessory sex organs weights, and epididymal sperm counts. In addition, inorganic arsenic exposure also induces alterations of spermatogenesis, reductions of testosterone and gonadotrophins, and disruptions of steroidogenesis. However, the reproductive and developmental problems following arsenic exposure are poorly understood, and the molecular mechanism of arsenic-induced reproductive toxicity remains unclear. Thus, we further investigated several possible mechanisms underlying arsenic-induced reproductive toxicity. PMID:26973968

  19. METHYLATION INACTIVATES PENTAVALENT ARSENIC SPECIES BUT ACTIVATES TRIVALENT ARSENIC SPECIES TO POTENT GENOTOXICANTS

    EPA Science Inventory

    Methylation Inactivates Pentavalent Arsenic Species but Activates Trivalent Arsenic Species to Potent Genotoxicants

    The sensitivity ofhumans to arsenic-induced cancer is thought to be related in part to the limited ability of humans to detoxify arsenic. Recently, methyl- ...

  20. Arsenic Toxicity to Juvenile Fish: Effects of Exposure Route, Arsenic Speciation, and Fish Species

    EPA Science Inventory

    Arsenic toxicity to juvenile rainbow trout and fathead minnows was evaluated in 28-day tests using both dietborne and waterborne exposures, both inorganic and organic arsenic species, and both a live diet and an arsenic-spiked pellet diet. Effects of inorganic arsenic on rainbow...