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Sample records for mercury 200 target

  1. Fabrication of mercury target vessel

    International Nuclear Information System (INIS)

    Wakui, Takashi; Kogawa, Hiroyuki; Haga, Katsuhiro; Futakawa, Masatoshi; Hayashi, Ryoichi; Uchiyama, Naoyoshi; Okamoto, Yoshinao; Nakamura, Koji

    2010-03-01

    The construction of materials and life science experimental facility in J-PARC (Japan Proton Accelerator Complex) project had been completed and accepted pulsed proton beams with low power. Since 2003, the detailed design, fabrication and examination for the mercury target vessel as a pulsed neutron source were carried out by the vender. The mercury target vessel consists of triple-walled structure in order to prevent the leak of mercury to outside at the failure of the mercury vessel and to remove the heat of the safety hull, which covers the mercury vessel, due to the injection of the pulsed proton beams. The high fabrication accuracy is required for the mercury target vessel assembled by the welding, because there are the relationships between the mercury target vessel and other components (target trolley, target storage container, flange of helium vessel, reflector and water-cooled shield). At each fabrication step, the examinations for the mercury target vessel with multi-walled structure were required. In this report, the required specification and basic structure of parts in the mercury target vessel are described and the fabrication procedure of the mercury target vessel by the vender is reported. In the fabrication of the mercury target vessel, there were many troubles such as large deformation due to the welding and then the vender repaired and brought the mercury target vessel to completion. Furthermore, improvements for the design and fabrication of the mercury target are reported. (author)

  2. 40 CFR 421.200 - Applicability: Description of the secondary mercury subcategory.

    Science.gov (United States)

    2010-07-01

    ... secondary mercury subcategory. 421.200 Section 421.200 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Secondary Mercury Subcategory § 421.200 Applicability: Description of the secondary mercury... mercury from secondary mercury facilities processing recycled mercuric oxide batteries and other mercury...

  3. Mercury erosion experiments for spallation target system

    International Nuclear Information System (INIS)

    Kinoshita, Hidetaka; Kaminaga, Masanori; Haga, Katsuhiro; Hino, Ryutaro

    2003-01-01

    The Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting a plan to construct the spallation neutron source at the Tokai Research Establishment, JAERI, under the High-Intensity Proton Accelerator Project (J-PARC). A mercury circulation system has been designed so as to supply mercury to the target stably under the rated flow rate of 41 m 3 /hr. Then, it was necessary to confirm a mercury pump performance from the viewpoint of making the mercury circulation system feasible, and more, to investigate erosion rate under the mercury flow as well as an amount of mercury remained on the surface after drain from the viewpoints of mechanical strength relating to the lifetime and remote handling of mercury components. The mercury pump performance was tested under the mercury flow conditions by using an experimental gear pump, which had almost the same structure as a practical mercury pump to be expected in the mercury circulation system, and the erosion rates in a mercury pipeline as well as the amount of mercury remained on the surface were also investigated. The discharged flow rates of the experimental gear pump increased linearly with the rotation speed, so that the gear pump would work as the flow meter. Erosion rates obtained under the mercury velocity less than 1.6 m/s was found to be so small that decrease of pipeline wall thickness would be 390 μm after 30-year operation under the rated mercury velocity of 0.7 m/s. For the amount of remaining mercury on the pipeline, remaining rates of weight and volume were estimated at 50.7 g/m 2 and 3.74 Hg-cm 3 /m 2 , respectively. Applying these remaining rates of weight and volume to the mercury target, the remaining mercury was estimated at about 106.5 g and 7.9 cm 3 . Radioactivity of this remaining mercury volume was found to be three-order lower than that of the target casing. (author)

  4. Radiochemical aspects of liquid mercury spallation targets

    CERN Document Server

    Neuhausen, Joerg; Eichler, Bernd; Eller, Martin; Horn, Susanne; Schumann, Dorothea; Stora, Thierry

    2012-01-01

    Liquid metal spallation targets using mercury as target material are used in state-of-the-art high power pulsed neutron sources that have been constructed in the USA and Japan within the last decade. Similar target concepts were also proposed for next generation ISOL, beta-beam and neutrino facilities. A large amount of radioactivity will be induced in the liquid metal during operation caused by the interaction of the target material with the intense proton beam. This radioactivity - carried by a wide range of radioisotopes of all the elements of the periodic table from hydrogen up to thallium - must be considered for the assessment of safe operation and maintenance procedures as well as for a final disposal of the used target material and components. This report presents an overview on chemical investigations performed in our laboratory that deal with the behavior of radionuclides in proton irradiated mercury samples. The solubility of elements in mercury was calculated using thermodynamical data obtained by...

  5. A self-focusing mercury jet target

    CERN Document Server

    Johnson, C

    2002-01-01

    Mercury jet production targets have been studied in relation to antiproton production and, more recently, pion production for a neutrino factory. There has always been a temptation to include some self-focusing of the secondaries by passing a current through the mercury jet analogous to the already proven lithium lens. However, skin heating of the mercury causes fast vaporization leading to the development of a gliding discharge along the surface of the jet. This external discharge can, nevertheless, provide some useful focusing of the secondaries in the case of the neutrino factory. The technical complications must not be underestimated.

  6. Activation calculation of the EURISOL mercury target

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, B.; David, J.C.; Blideanu, V.; Dore, D.; Ridikas, D.; Thiolliere, N

    2006-08-15

    We have used MCNPX coupled to CINDER to estimate the production of radioactive nuclides in the EURISOL 4 MW liquid mercury target during a 40 years'lifetime of the installation. The calculations have been done with different intra-nuclear cascade and fission evaporation model combinations. A benchmark exercise has allowed a better understanding of differences seen between these models for the creation of tritium and fission products. To obtain a realistic production yield for tritium gas in proton induced spallation reactions, we recommend using the ISABEL-RAL model, while both CEM2k and BERTINI-RAL overestimate the production rate above 1 GeV incident proton. The best combinations of models to calculate the residual nuclei production are those using ABLA fission-evaporation model, CEM2k or combinations using RAL model are giving too broad mass distributions when compared to available data. An extensive list of radio-nuclides was obtained and is available on tabular format, we show that the 4 nuclei whose contributions to the total activity of the mercury target (after 40 years of irradiation) are the most important are the following: -) 1 day after shutdown: Y{sup 91} (15%), Y{sup 90} (13%), Hg{sup 197} (6%) and Sr{sup 89} (5%); -) 1 year after shutdown: H{sup 3} (19%), Y{sup 90} (17%), Sr{sup 90} (17%) and Nb{sup 93*} (10%); -) 10 years after shutdown: Y{sup 90} (22%), Sr{sup 90} (22%), H{sup 3} (18%) and Nb{sup 93*} (14%); and -) 100 years after shutdown: Mo{sup 93} (34%), Nb{sup 93*} (32%), Pt{sup 193} (9%) and Y{sup 90} (8%). (A.C.)

  7. Thermal shocks and magnetohydrodynamics in high power mercury jet targets

    CERN Document Server

    Lettry, Jacques; Gilardoni, S S; Benedikt, Michael; Farhat, M; Robert, E

    2003-01-01

    The response of mercury samples submitted to a pulsed proton beam and the magnetohydrodynamic (MHD) effects of a mercury jet injected into a 20 T magnetic field are reported. The experimental conditions differ from those of proposed neutrino factories and the purpose of these measurements is to provide benchmarks for simulation tools of a realistic free mercury jet target. These measurements were completed in June 2002. Analysis is ongoing and the presented results are preliminary. (12 refs).

  8. Solubility of helium in mercury for bubbling technology of the spallation neutron mercury target

    International Nuclear Information System (INIS)

    Hasegawa, S.; Naoe, T.; Futakawa, M.

    2010-01-01

    The pitting damage of mercury target container that originates in the pressure wave excited by the proton beam incidence becomes a large problem to reach the high-power neutron source in JSNS and SNS. The lifetime of mercury container is decreased remarkably by the pitting damage. As one of solutions, the pressure wave is mitigated by injecting the helium micro bubbles in mercury. In order to inject the helium micro bubbles into mercury, it is important to understand the characteristic of micro bubbles in mercury. The solubility of mercury-helium system is a key factor to decide bubbling conditions, because the disappearance behavior, i.e. the lifetime of micro bubbles, depends on the solubility. In addition, the bubble generation method is affected by it. Moreover, the experimental data related to the solubility of helium in mercury hardly exist. In this work, the solubility was obtained experimentally by measuring precisely the pressure drop of the gas that is facing to mercury surface. The pressure drop was attributed to the helium dissolution into mercury. Based on the measured solubility, the lifetime of micro bubbles and the method of the bubble generation is estimated using the solubility data.

  9. Support Facility for a Mercury Target Neutrino Factory

    Energy Technology Data Exchange (ETDEWEB)

    Spampinato, P.T.

    2001-12-06

    A conceptual design for a neutrino-producing facility is presented, including the mercury-jet target system, beam absorber, and facility for the target/capture region. The mercury system is a closed loop that includes a containment structure in the high-magnetic field region, a mercury pool beam absorber, conventional equipment such as magnetic-coupled pumps, valves, a heat exchanger, and a special nozzle insert. The superconducting solenoids in the target region are protected from nuclear heating and radiation damage with water-cooled tungsten-carbide shielding; the decay channel solenoids are protected with water-cooled steel shielding. The target region and decay channel have high-neutron fluxes resulting in components that are highly activated. Therefore, the facility configuration is based on remotely maintaining the target system and the magnets, as well as providing sufficient shielding for personnel. Summaries of cost estimates for the target system, magnet shielding, maintenance equipment, and the facility are also presented.

  10. Off-line tests on pitting damage in mercury target

    CERN Document Server

    Futakawa, M; Ishikura, S; Kogawa, H; Tsai, C C

    2003-01-01

    A liquid-mercury target system for the MW-scale target is being developed in the world. The moment the proton beams bombard the target, stress waves will be imposed on the beam window and pressure waves will be generated in the mercury by the thermally shocked heat deposition. Provided that the negative pressure generates through its propagation in the mercury target and causes cavitation in the mercury, there is the possibility for the cavitation bubbles collapse to form pits on the interface between the mercury and the target vessel wall. In order to estimate the cavitation erosion damage due to pitting, two types of off-line tests were performed: Split Hopkinson Pressure Bar (SHPB), and Magnetic IMpact Testing Machine (MIMTM). The data on the piping damage at the high cycle impacts up to 10 million were given by the MIMTM. Additionally the data obtained were compared with classical vibratory horn tests. As a result, it is confirmed that the mean depth erosion is predictable using a homologous line in the s...

  11. Structural integrity of beam window of mercury target

    International Nuclear Information System (INIS)

    Kogawa, Hiroyuki; Ishikura, Syuichi; Futakawa, Masatoshi; Kaminaga, Masanori; Hino, Ryutaro

    2003-01-01

    The developments of a MW-class spallation neutron source facility are being carried out under the high-intensity proton accelerator project promoted by JAERI and KEK. A mercury target will be used as a neutron source in the facility. The mercury target vessel made of 316LSS will be subjected to pressure wave generated by rapid thermal expansion of mercury due to a pulsed proton beam injection. The pressure wave will make huge dynamic stress on the vessel and will deform the vessel, which would cause cavitation in mercury. To estimate the structural integrity of the mercury target vessel, especially beam window, dynamic stress behaviors due to 1 MW-pulsed proton beam injection were analyzed by using FEM code. In the analyses, two types of the target vessels with semi-cylindrical and flat type windows were used as analytical models. As the results, it has been understood that the stress generated in the beam window by the pressure wave could be treated as the secondary stress. Also it was confirmed that the flat type window would be more advantageous from the structural viewpoint than the semi-cylindrical type window. (author)

  12. Mercury

    International Nuclear Information System (INIS)

    Vilas, F.; Chapman, C.R.; Matthews, M.S.

    1988-01-01

    Papers are presented on future observations of and missions to Mercury, the photometry and polarimetry of Mercury, the surface composition of Mercury from reflectance spectrophotometry, the Goldstone radar observations of Mercury, the radar observations of Mercury, the stratigraphy and geologic history of Mercury, the geomorphology of impact craters on Mercury, and the cratering record on Mercury and the origin of impacting objects. Consideration is also given to the tectonics of Mercury, the tectonic history of Mercury, Mercury's thermal history and the generation of its magnetic field, the rotational dynamics of Mercury and the state of its core, Mercury's magnetic field and interior, the magnetosphere of Mercury, and the Mercury atmosphere. Other papers are on the present bounds on the bulk composition of Mercury and the implications for planetary formation processes, the building stones of the planets, the origin and composition of Mercury, the formation of Mercury from planetesimals, and theoretical considerations on the strange density of Mercury

  13. Optical diagnostics of mercury jet for an intense proton target.

    Science.gov (United States)

    Park, H; Tsang, T; Kirk, H G; Ladeinde, F; Graves, V B; Spampinato, P T; Carroll, A J; Titus, P H; McDonald, K T

    2008-04-01

    An optical diagnostic system is designed and constructed for imaging a free mercury jet interacting with a high intensity proton beam in a pulsed high-field solenoid magnet. The optical imaging system employs a backilluminated, laser shadow photography technique. Object illumination and image capture are transmitted through radiation-hard multimode optical fibers and flexible coherent imaging fibers. A retroreflected illumination design allows the entire passive imaging system to fit inside the bore of the solenoid magnet. A sequence of synchronized short laser light pulses are used to freeze the transient events, and the images are recorded by several high speed charge coupled devices. Quantitative and qualitative data analysis using image processing based on probability approach is described. The characteristics of free mercury jet as a high power target for beam-jet interaction at various levels of the magnetic induction field is reported in this paper.

  14. Estimation of thermochemical behavior of spallation products in mercury target

    International Nuclear Information System (INIS)

    Kobayashi, Kaoru; Kaminaga, Masanori; Haga, Katsuhiro; Kinoshita, Hidetaka; Aso, Tomokazu; Teshigawara, Makoto; Hino, Ryutaro

    2002-02-01

    In order to examine the radiation safety of a spallation mercury target system, especially source term evaluation, it is necessary to clarify the chemical forms of spallation products generated by spallation reaction with proton beam. As for the chemical forms of spallation products in mercury that involves large amounts of spallation products, these forms were estimated by using the binary phase diagrams and the thermochemical equilibrium calculation based on the amounts of spallation product. Calculation results showed that the mercury would dissolve Al, As, B, Be, Bi, C, Co, Cr, Fe, Ga, Ge, Ir, Mo, Nb, Os, Re, Ru, Sb, Si, Ta, Tc, V and W in the element state, and Ag, Au, Ba, Br, Ca, Cd, Ce, Cl, Cs, Cu, Dy, Er, Eu, F, Gd, Hf, Ho, I, In, K, La, Li, Lu, Mg, Mn, Na, Nd, Ni, O, Pb, Pd, Pr, Pt, Rb, Rh, S, Sc, Se, Sm, Sn, Sr, Tb, Te, Ti, Tl, Tm, Y, Yb, Zn and Zr in the form of inorganic mercury compounds. As for As, Be, Co, Cr, Fe, Ge, Ir, Mo, Nb, Os, Pt, Re, Ru, Se, Ta, V, W and Zr, precipitation could be occurred when increasing the amounts of spallation products with operation time of the spallation target system. On the other hand, beryllium-7 (Be-7), which is produced by spallation reaction of oxygen in the cooling water of a safety hull, becomes the main factor of the external exposure to maintain the cooling loop. Based on the thermochemical equilibrium calculation to Be-H 2 O binary system, the chemical forms of Be in the cooling water were estimated. Then the Be could exist in the form of cations such as BeOH + , BeO + and Be 2+ under the condition of less than 10 -8 of the Be mole fraction in the cooling water. (author)

  15. Estimation of thermochemical behavior of spallation products in mercury target

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Kaoru; Kaminaga, Masanori; Haga, Katsuhiro; Kinoshita, Hidetaka; Aso, Tomokazu; Teshigawara, Makoto; Hino, Ryutaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2002-02-01

    In order to examine the radiation safety of a spallation mercury target system, especially source term evaluation, it is necessary to clarify the chemical forms of spallation products generated by spallation reaction with proton beam. As for the chemical forms of spallation products in mercury that involves large amounts of spallation products, these forms were estimated by using the binary phase diagrams and the thermochemical equilibrium calculation based on the amounts of spallation product. Calculation results showed that the mercury would dissolve Al, As, B, Be, Bi, C, Co, Cr, Fe, Ga, Ge, Ir, Mo, Nb, Os, Re, Ru, Sb, Si, Ta, Tc, V and W in the element state, and Ag, Au, Ba, Br, Ca, Cd, Ce, Cl, Cs, Cu, Dy, Er, Eu, F, Gd, Hf, Ho, I, In, K, La, Li, Lu, Mg, Mn, Na, Nd, Ni, O, Pb, Pd, Pr, Pt, Rb, Rh, S, Sc, Se, Sm, Sn, Sr, Tb, Te, Ti, Tl, Tm, Y, Yb, Zn and Zr in the form of inorganic mercury compounds. As for As, Be, Co, Cr, Fe, Ge, Ir, Mo, Nb, Os, Pt, Re, Ru, Se, Ta, V, W and Zr, precipitation could be occurred when increasing the amounts of spallation products with operation time of the spallation target system. On the other hand, beryllium-7 (Be-7), which is produced by spallation reaction of oxygen in the cooling water of a safety hull, becomes the main factor of the external exposure to maintain the cooling loop. Based on the thermochemical equilibrium calculation to Be-H{sub 2}O binary system, the chemical forms of Be in the cooling water were estimated. Then the Be could exist in the form of cations such as BeOH{sup +}, BeO{sup +} and Be{sup 2+} under the condition of less than 10{sup -8} of the Be mole fraction in the cooling water. (author)

  16. Mercury

    NARCIS (Netherlands)

    de Vries, Irma

    2017-01-01

    Mercury is a naturally occurring metal that exists in several physical and chemical forms. Inorganic mercury refers to compounds formed after the combining of mercury with elements such as chlorine, sulfur, or oxygen. After combining with carbon by covalent linkage, the compounds formed are called

  17. Investigation of flow asymmetry and instability in the liquid mercury target of the Spallation Neutron Source

    International Nuclear Information System (INIS)

    Pointer, D.; Ruggles, A.; Wendel, M.; Crye, J.

    2000-01-01

    The Spallation Neutron Source (SNS) will utilize a liquid mercury target placed in the path of a high-energy proton beam to produce neutrons for research activities. As the high-energy protons interact with the mercury target, the majority of the beam energy is converted to thermal energy. The liquid mercury must provide sufficient heat transfer to maintain the temperature of the target structure within the thermal limits of the structural materials. Therefore, the behavior of the liquid mercury flow must be characterized in sufficient detail to ensure accurate evaluation of heat transfer in the mercury target. A combination of experimental and computational methods is utilized to characterize the flow in these preliminary analyses. Preliminary studies of the liquid mercury flow in the SNS target indicate that the flow in the exit channel may exhibit multiple recirculation zones, flow asymmetries, and possibly large-scale flow instabilities. While these studies are not conclusive, they serve to focus the efforts of subsequent CFD modeling and experimental programs to better characterize the flow patterns in the SNS mercury target

  18. System dynamic analyses on the JKJ mercury target and cold moderator systems

    International Nuclear Information System (INIS)

    Takahashi, Toshio; Kaminaga, Masanori; Kinoshita, Hidetaka; Aso, Tomokazu; Haga, Katsuhiro; Hino, Ryutaro

    2001-01-01

    The temperature responses of major points in a mercury target cooling system and in a cold moderator system of JKJ (JAERI/KEK Joint Project) were simulated by the analytical code MATLAB (SIMULINK). As a result, it was made clear that non-control of mercury temperature is the best way to control the mercury target cooling system. If the mercury temperature of the system is controlled by the PID control system using an outlet temperature of heat exchanger, the PID control system shows the characteristics of an on-off control system, and the temperature cannot be controlled. Analytical results also showed that mercury temperature remained below the boiling point of 356degC under 0.1 MPa during a transient at one cooling pump trip. Analytical results for the cold moderator system showed that the outlet temperature of cold moderator vessels could be kept within a temperature range of 1 k during steady-state conditions. (author)

  19. CALCULATIONS FOR A MERCURY JET TARGET IN A SOLENOID MAGNET CAPTURE SYSTEM

    International Nuclear Information System (INIS)

    GALLARDO, J.; KAHN, S.; PALMER, R.B.; THIEBERGER, P.; WEGGEL, R.J.; MCDONALD, K.

    2001-01-01

    A mercury jet is being considered as the production target for a muon storage ring facility to produce an intense neutrino beam. A 20 T solenoid magnet that captures pions for muon production surrounds the mercury target. As the liquid metal jet enters or exits the field eddy currents are induced. We calculate the effects that a liquid metal jet experiences in entering and exiting the magnetic field for the magnetic configuration considered in the Neutrino Factory Feasibility Study II

  20. Mercury

    Science.gov (United States)

    ... build up in fish, shellfish, and animals that eat fish. The nervous system is sensitive to all forms of mercury. Exposure to high levels can damage the brain and kidneys. Pregnant women can pass the mercury in their bodies to their babies. It is important to protect your family from ...

  1. Mercury

    Science.gov (United States)

    ... has set a limit of 2 parts of mercury per billion parts of drinking water (2 ppb). The Food and Drug Administration (FDA) has set a maximum permissible level of 1 part of methylmercury in a million ... of 0.1 milligram of organic mercury per cubic meter of workplace air (0.1 ...

  2. Mockup experiments to investigate the leak rate correlation between mercury and helium for the mercury target system of J-PARC

    International Nuclear Information System (INIS)

    Haga, Katsuhiro; Naoe, Takashi; Kogawa, Hiroyuki; Wakui, Takashi; Futakawa, Masatoshi

    2009-01-01

    Checking the seal performance of the mercury piping network is very important for the mercury target system operation of J-PARC, and the test method for leaks using the pressure change measurement is preferable for this purpose because it can be carried out easily and precisely by measuring the pressure change, and it is free from the risk of mercury contamination. The piping network is pressurized by helium gas. Thus, the correlation between the helium leak rate and mercury leak flow rate was investigated experimentally by carrying out leak tests for helium and mercury with an identical mockup flange model. The results showed that the mercury leak flow rates of the experimental data were lower than those of the estimated value by 64% on average. It was also found that the threshold of the helium leak rate at which good seal performance for mercury can be obtained exists between 2.18 x 10 -4 and 1.01 x 10 -2 Pa.m 3 /s. This fact confirmed the sufficient safety margin of the mercury target system against the mercury leak, where 1 x 10 -6 Pa.m 3 /s was adopted as the seal performance criterion. (author)

  3. Optimization of a mercury jet target for a neutrino factory or a muon collider

    Directory of Open Access Journals (Sweden)

    X. Ding

    2011-11-01

    Full Text Available A study of target parameters for a mercury jet target for a neutrino factory or muon collider is presented. We simulate particle production initiated by incoming protons with kinetic energies between 2 and 100 GeV. For each proton beam kinetic energy, we maximize production by varying the geometric parameters of the target: the mercury jet radius, the incoming proton beam angle, and the crossing angle between the mercury jet and the proton beam. With an 8-GeV proton beam, we study the variation of meson production with the entry direction of the proton beam relative to the jet. We also examine the influence on the meson production by the focusing of the proton beam. The number of muons surviving through the neutrino factory front end channel is determined as a function of the proton beam kinetic energy.

  4. Mercury

    CERN Document Server

    Balogh, André; Steiger, Rudolf

    2008-01-01

    Mercury, the planet closest to the Sun, is different in several respects from the other three terrestrial planets. In appearance, it resembles the heavily cratered surface of the Moon, but its density is high, it has a magnetic field and magnetosphere, but no atmosphere or ionosphere. This book reviews the progress made in Mercury studies since the flybys by Mariner 10 in 1974-75, based on the continued research using the Mariner 10 archive, on observations from Earth, and on increasingly realistic models of its interior evolution.

  5. CFD analysis of a liquid mercury target for the National Spallation Neutron Source

    International Nuclear Information System (INIS)

    Wendel, M.W.; Tov, M.S.

    1997-01-01

    Computational fluid dynamics (CFD) is being used to analyze the design of the National Spallation Neutron Source (NSNS) target. The target is subjected to the neutronic (internal) heat generation that results from the proton collisions with the mercury nuclei. The liquid mercury simultaneously serves as the neutronic target medium, transports away the heat generated within itself, and cools the metallic target structure. Recirculation and stagnation zones within the target are of particular concern because of the likelihood that they will result in local hot spots. These zones exist because the most feasible target designs include a complete U-turn flow redirection. Although the primary concern is that the target is adequately cooled, the pressure drop from inlet to outlet must also be considered because pressure drop directly affects structural loading and required pumping power. Various design options have been considered in an effort to satisfy these design criteria. Significant improvements to the design have been recommended based on the results. Detailed results are presented for the current target design including a comparison with published pressure-drop data. Comparisons are also made with forced convection heat transfer data for liquid mercury flow in circular tubes

  6. The Merit(nTOF-11) High Intensity Liquid Mercury Target Experiment at the CERN PS

    CERN Document Server

    Efthymiopoulos, I; Caretta, O; Carroll, A J; Fabich, A; Graves, V B; Grudiev, A; Haug, F; Kirk, H G; Lettry, Jacques; Loveridge, P; McDonald, K T; Mokhov, N; Palm, M; Park, H; Pernegger, H; Spampinato, P T; Steerenberg, R; Striganov, S; Tsang, T

    2008-01-01

    The MERIT(nTOF-11) experiment is a proof-ofprinciple test of a target system for a high power proton beam to be used as front-end for a neutrino factory or a muon collider. The experiment took data in autumn 2007 with the fast-extracted beam from the CERN Proton Synchrotron (PS) to a maximum intensity of $30 × 10^{12}$ per pulse. The target system, based on a free mercury jet, is capable of intercepting a 4-MW proton beam inside a 15-T magnetic field required to capture the low energy secondary pions as the source for intense muon beams. Partice detectors installed around the target setup measure the secondary particle flux out of the target and can probe cavitation effects in the mercury jet when excited by an intense proton beam.Preliminary results of the data analysis will be presented here.

  7. 2-PROTON CORRELATIONS IN THE TARGET FRAGMENTATION REGION OF NUCLEAR COLLISIONS AT 200-A-GEV

    NARCIS (Netherlands)

    AWES, TC; BARLAG, C; BERGER, F; BLOOMER, MA; BLUME, C; BOCK, D; BOCK, R; BOHNE, EM; BUCHER, D; CLAUSSEN, A; CLEWING, G; DRAGON, L; EKLUND, A; GARPMAN, S; GLASOW, R; GUTBROD, HH; HOLKER, G; IDH, J; JACOBS, P; KAMPERT, KH; KOLB, BW; LOHNER, H; LUND, [No Value; OBENSHAIN, FE; OSKARSSON, A; OTTERLUND, [No Value; PEITZMANN, T; PLASIL, F; POSKANZER, AM; PURSCHKE, M; ROTERS, B; SAINI, S; SANTO, R; SCHMIDT, HR; SORENSEN, SP; STEFFENS, K; STEINHAEUSER, P; STENLUND, E; STUKEN, D; YOUNG, GR

    Correlations between protons are studied in the target fragmentation region of reactions of protons and O-16 with C, Cu, Ag, Au and of S-32 With Al and Au at 200 A GeV. The emitted protons were measured with the Plastic Ball detector in the WA80 experiment at the CERN SPS. The comparison of the

  8. miR-200c suppresses endometriosis by targeting MALAT1 in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Zongwen Liang

    2017-11-01

    Full Text Available Abstract Background Endometriosis is a common, benign, and estrogen-dependent disease characterized by pelvic pain and infertility. To date, the pathogenesis of endometriosis remains unclear. Recent studies have demonstrated that noncoding RNAs, including microRNAs and long noncoding RNAs, play important roles in the development of endometriosis. Methods Expression profiling of miRNAs in endometrial tissue was characterized using microarrays. The most differentially expressed miRNAs were confirmed using quantitative reverse transcriptase-polymerase chain reaction analysis in additional ectopic endometrial (n = 27 and normal endometrial (n = 12 tissues. For in-vitro functional studies, 5-ethynyl-2′-deoxyuridine incorporation assay, Transwell assay, and dual-luciferase reporter assay were used to measure the proliferation, migration, and luciferase activity of miR-200c and the predicted targets of miR-200c in primary endometrial stromal cells (HESCs derived from human endometrial biopsies, respectively. For in-vivo therapeutic interventions, polymeric nanoparticles of polyethylenimine–polyethylene glycol–arginine–glycine–aspartic acid were used for delivery of miR-200c mimic and inhibitor to determine the therapeutic effect of miR-200c in a rat model of endometriosis. Results Exogenous overexpression of miR-200c inhibited the proliferation and migration of HESCs, which were mainly regulated by metastasis-associated lung adenocarcinoma transcript 1 (MALAT1. In contrast, inhibition of miR-200c promoted the proliferation and migration of HESCs, while the simultaneous silencing of MALAT1 expression exerted the opposite effects. We demonstrated that expression of MALAT1 in ectopic endometrial specimens was negatively correlated with that of miR-200c and that MALAT1 knockdown increased the level of miR-200c in HESCs. Moreover, the transfection of endometrial stromal cells with the miR-200c mimic or MALAT1 siRNAs decreased the protein

  9. Thermal shock analysis of liquid-mercury spallation target

    CERN Document Server

    Ishikura, S; Futakawa, M; Hino, R; Date, H

    2002-01-01

    The developments of the neutron scattering facilities are carried out under the high-intensity proton accelerator project promoted by JAERI and KEK. To estimate the structural integrity of the heavy liquid-metal (Hg) target used as a spallation neutron source in a MW-class neutron scattering facility, dynamic stress behavior due to the incident of a 1 MW-pulsed proton beam was analyzed by using FEM code. Two-type target containers with semi-cylindrical type and flat-plate type window were used as models for analyses. As a result, it is confirmed that the stress (pressure wave) generated by dynamic thermal shock becomes the largest at the center of window, and the flat-plate type window is more advantageous from the structural viewpoint than the semi-cylindrical type window. It has been understood that the stress generated in the window by the pressure wave can be treated as the secondary stress. (author)

  10. Intense neutron source target test facility: a 200 mA dc, deuterium ion accelerator

    International Nuclear Information System (INIS)

    Bacon, F.M.; Riedel, A.A.

    1978-01-01

    A 200 kV, 200 mA dc, deuterium ion accelerator has been constructed to evaluate high-temperature hydride materials such as scandium and erbium for use as targets in D--T neutron generators. The metal hydride film is deposited on a water-cooled, copper substrate designed to handle power densities of 40 MW/m 2 while maintaining a surface temperature of less than or equal to 450 0 C. The goal of this program is to develop a target for a D--T neutron generator capable of producing 10 13 neutrons/s for use in cancer therapy. The accelerator employs a small duopigatron ion source which is capable of delivering a 200 mA deuterium ion beam that is composed of 60% atomic ions. The ion source is held at positive high voltage and a beam is formed with a single stage accel gap. An extractor electrode is biased negative about 2 kV to suppress secondary electrons and to define the point along the beam axis where the beam is space-charge neutralized by the trapped secondary electrons. The distance from the plasma expansion cup to the target is 0.6 m. Ion beam diameters at the target have been determined from measured infrared radiance profiles of the target due to beam heating. Data are presented on ion beam diameters for several operating conditions and accelerator geometries. D--D neutron output rates of 6 x 10 10 neutrons/s have been measured with a 200 kV, 180 mA beam on erbium and a 180 kV, 160 mA beam on scandium

  11. Mercury purification in the megawatt liquid metal spallation target of EURISOL-DS

    CERN Document Server

    Neuhausen, Joerg; Eller, Martin; Schumann, Dorothea; Eichler, Bernd; Horn, Susanne

    High power spallation targets are going to be used extensively in future research and technical facilities such as spallation neutron sources, neutrino factories, radioactive beam facilities or accelerator driven systems for the transmutation of long-lived nuclear waste. Within EURISOL-DS, a 4 MW liquid metal spallation target is designed to provide neutrons for a fission target, where neutron rich radionuclides will be produced. For the spallation target, mercury is planned to be used as target material. A large amount of radionuclides ranging from atomic number Z=1 to 81 will be produced in the liquid metal during long term irradiation. It is planned to remove those radionuclides by chemical or physicochemical methods to reduce its radioactivity. For the development of a purification procedure, knowledge about the chemical state of the different elements present in the mixture is required. We present a general concept of applicable separation techniques in a target system and show some results of experiment...

  12. Thermal-hydraulic design of cross-flow type mercury target for JAERI/KEK joint project

    International Nuclear Information System (INIS)

    Kaminaga, Masanori; Terada, Atsuhiko; Haga, Katsuhiro; Kinoshita, Hidetaka; Hino, Ryutaro

    2001-01-01

    The Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting a plan to construct a neutron scattering facility. In the facility, 1 MW pulsed proton beam from a high-intensity proton accelerator will be injected into a mercury target in order to produce high-intensity neutrons for use in the fields of life and material sciences. In the spallation mercury target system design, an integrated structure of target vessel with a safety hull was proposed to ensure the safety and to collect mercury in case of mercury leakage caused by the target beam window failure. The inner structure arrangement of the mercury target vessel was determined based on the thermal hydraulic analytical results of 3 GeV, 1 MW proton beam injection. The safety hull consists of vessels for helium and heavy water. The vessels for mercury target, helium and heavy water will be connected each other by reinforcement ribs mounted on the surface of each vessel. From the structural analyses, the structural integrity of the safety hull would be maintained under the static pressure of 0.5 MPa. (author)

  13. Innovative Waste Management in the Mercury Loop of the EURISOL Multi-MW Converter Target

    CERN Document Server

    PSI: Jörg Neuhausen, Dorothea Schumann, Rugard Dressler, Susanne Horn, Sabrina Lüthi, Stephan Heinitz, Suresh ChirikiCERN: Thierry Stora, Martin Eller

    The choice of mercury as target material imposes various questions concerning the safe operation of such a system that are related to the physical and chemical properties of the target material itself and the nuclear reaction products produced within the target during its life time of several decades. Therefore, a subtask was created within the EURISOL-DS project that is concerned with studying an innovative waste management for the generated radioactivity by chemical means. Such a study strongly depends on the radioactive inventory and its distribution throughout the target and loop system. Radioactive inventory calculations were performed within task 5 [6]. The distribution of nuclear reaction products and their chemical state that can be expected within the target and loop system is one of the topics covered in this report. Based on the results obtained by theoretical studies as well as laboratory scale experiments, the feasibility of waste reduction using chemical methods, both conventional (e.g. leaching...

  14. MERIT - The high intensity liquid mercury target experiment at the CERN PS

    CERN Document Server

    Efthymiopoulos, I

    2009-01-01

    The MERIT experiment is a proof-of-principle test of a target system for high power proton beams to be used as front-end for a Neutrino Factory complex or a Muon Collider. The experiment took data in autumn 2007 with the fast extracted beam from the CERN Proton Synchrotron (PS) to a maximum intensity of about 30 × 1012 protons per pulse. The target system, based on a free mercury jet, allowed investigation of the interseption of a 4-MW proton beam inside a 15-T magnetic field required to capture the low-energy secondary pions as the source of the required intense muon beams. Particle detectors have been installed around the target setup to measure the secondary particle flux out of the target and probe cavitation effects in the mercury jet when exited with a beam of variable intensity. With the analysis of the data ongoing, results will be presented here that demonstrate the validity of the liquid target concept.

  15. Measurement of spectrum for thermal neutrons produced from H2O moderator coupled with mercury target

    International Nuclear Information System (INIS)

    Meigo, S.; Maekawa, F.; Kasugai, Y.; Nakashima, H.; Ikeda, Y.; Watanabe, N.

    2001-01-01

    In order to obtain fundamental data for the design of pulsed spallation neutron source, the slowing-down and thermalized neutrons from an H 2 O moderator coupled with the mercury target were measured using GeV proton beams at AGS (Alternative Gradient Synchrotron) in BNL (Brookhaven National Laboratory) under the ASTE (AGS-Spallation Target Experiment) collaboration. The mercury target (φ 20 cm x L 130 cm) was surrounded by a lead reflector (1 x 1 x 1 m 3 ) was irradiated by 1.94-, 12- and 24-GeV protons. The spectral intensities of thermal neutrons from the moderator are measured by the current-mode time-of-flight technique using enriched 6 Li and 7 Li glass scintillators. By this technique, only several incident pulses were needed to obtain sufficient statistics for incident energy. The results have shown that the neutron spectral intensity per proton integrated over the Maxwellian region was almost proportional to the proton energy. By moving the target along the beam direction within 15 cm, the dependence of the relative moderator position to the target on the neutron flux was also measured. With this position change, the difference with flux was found within 10%. (author)

  16. Mercury-induced hepatotoxicity in zebrafish: in vivo mechanistic insights from transcriptome analysis, phenotype anchoring and targeted gene expression validation

    Directory of Open Access Journals (Sweden)

    Mathavan Sinnakaruppan

    2010-03-01

    Full Text Available Abstract Background Mercury is a prominent environmental contaminant that causes detrimental effects to human health. Although the liver has been known to be a main target organ, there is limited information on in vivo molecular mechanism of mercury-induced toxicity in the liver. By using transcriptome analysis, phenotypic anchoring and validation of targeted gene expression in zebrafish, mercury-induced hepatotoxicity was investigated and a number of perturbed cellular processes were identified and compared with those captured in the in vitro human cell line studies. Results Hepato-transcriptome analysis of mercury-exposed zebrafish revealed that the earliest deregulated genes were associated with electron transport chain, mitochondrial fatty acid beta-oxidation, nuclear receptor signaling and apoptotic pathway, followed by complement system and proteasome pathway, and thereafter DNA damage, hypoxia, Wnt signaling, fatty acid synthesis, gluconeogenesis, cell cycle and motility. Comparative meta-analysis of microarray data between zebrafish liver and human HepG2 cells exposed to mercury identified some common toxicological effects of mercury-induced hepatotoxicity in both models. Histological analyses of liver from mercury-exposed fish revealed morphological changes of liver parenchyma, decreased nucleated cell count, increased lipid vesicles, glycogen and apoptotic bodies, thus providing phenotypic evidence for anchoring of the transcriptome analysis. Validation of targeted gene expression confirmed deregulated gene-pathways from enrichment analysis. Some of these genes responding to low concentrations of mercury may serve as toxicogenomic-based markers for detection and health risk assessment of environmental mercury contaminations. Conclusion Mercury-induced hepatotoxicity was triggered by oxidative stresses, intrinsic apoptotic pathway, deregulation of nuclear receptor and kinase activities including Gsk3 that deregulates Wnt signaling

  17. Martensitic/ferritic steels as container materials for liquid mercury target of ESS

    International Nuclear Information System (INIS)

    Dai, Y.

    1996-01-01

    In the previous report, the suitability of steels as the ESS liquid mercury target container material was discussed on the basis of the existing database on conventional austenitic and martensitic/ferritic steels, especially on their representatives, solution annealed 316 stainless steel (SA 316) and Sandvik HT-9 martensitic steel (HT-9). Compared to solution annealed austenitic stainless steels, martensitic/ferritic steels have superior properties in terms of strength, thermal conductivity, thermal expansion, mercury corrosion resistance, void swelling and irradiation creep resistance. The main limitation for conventional martensitic/ferritic steels (CMFS) is embrittlement after low temperature (≤380 degrees C) irradiation. The ductile-brittle transition temperature (DBTT) can increase as much as 250 to 300 degrees C and the upper-shelf energy (USE), at the same time, reduce more than 50%. This makes the application temperature range of CMFS is likely between 300 degrees C to 500 degrees C. For the present target design concept, the temperature at the container will be likely controlled in a temperature range between 180 degrees C to 330 degrees C. Hence, CMFS seem to be difficult to apply. However, solution annealed austenitic stainless steels are also difficult to apply as the maximum stress level at the container will be higher than the design stress. The solution to the problem is very likely to use advanced low-activation martensitic/ferritic steels (LAMS) developed by the fusion materials community though the present database on the materials is still very limited

  18. MicroRNA-200a inhibits cell growth and metastasis by targeting Foxa2 in hepatocellular carcinoma.

    Science.gov (United States)

    Chen, Shu-Ying; Ma, De-Ning; Chen, Qiu-Dan; Zhang, Jing-Jun; Tian, Yue-Ru; Wang, Zhi-Cheng; Cai, Hao; Lin, Yong; Sun, Hui-Chuan

    2017-01-01

    Background: MicroRNAs (miRNAs) are a class of endogenous, small non-coding RNAs which function as essential posttranscriptional modulators of gene expression tightly involved in a wide range of diseases, including the hepatocellular carcinoma (HCC). Here, the present study was designed to investigate the expression levels and cellular roles of miR-200a in HCC. Methods: Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) was used to detect the expression levels of miR-200a in serums and cell lines. Bioinformation analysis, the luciferase reporter assay, qRT-PCR and western blotting were employed to validate Foxa2 as a direct target gene of miR-200a. Cell proliferation, migration and invasion were assessed to identify whether miR-200a could regulate the biological behaviors of HCC cells by targeting Foxa2. Results: In this study, a low level of miR-200a was observed in patients' serums and HCC cell lines. Overexpression of miR-200a in HCC cell lines reduced cell proliferation, migration and invasion. In addition, transcription factor forkhead box A2 (Foxa2) was identified as a novel target of miR-200a and downregulated at mRNA and protein levels in miR-200a overexpressed cells. Meanwhile, restoration of Foxa2 significantly reversed the tumor suppressive effects of miR-200a. Conclusions: These findings indicate that miR-200a regulates the proliferation, migration and invasion of HCC cells by targeting Foxa2, suggesting that miR-200a may function as a potential therapeutic molecular for the diagnosis and treatment of the liver cancer.

  19. Identification of targets of miR-200b by a SILAC-based quantitative proteomic approach

    Directory of Open Access Journals (Sweden)

    Arivusudar Marimuthu

    2014-09-01

    Full Text Available miRNAs regulate gene expression by binding to cognate mRNAs causing mRNA degradation or translational repression. Mass spectrometry-based proteomic analysis is being widely used to identify miRNA targets. The miR-200b miRNA cluster is often overexpressed in multiple cancer types, but the identity of the targets remains elusive. Using SILAC-based analysis, we examined the effects of overexpression of a miR-200b mimic or a control miRNA in fibrosarcoma cells. We identified around 300 potential targets of miR-200b based on a change in the expression of protein levels. We validated a subset of potential targets at the transcript level using quantitative PCR.

  20. Measurement of induced radioactivity in a spallation neutron field of a mercury target for GeV-proton bombardment

    Energy Technology Data Exchange (ETDEWEB)

    Kasugai, Y.; Takada, H.; Nakashima, H. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    2001-03-01

    An integral experiment on radioactivity induced in spallation neutron fields was carried out under the ASTE (AGS-Spallation Target Experiment) collaboration using AGS (Alternative Gradient Synchrotron) at BNL (Brookhaven National Laboratory). The spallation neutrons were produced by bombarding a mercury target with protons of 1.6, 12 and 24 GeV. The number of protons was 3 - 4 x 10{sup 13} for each irradiation. The irradiated materials were titanium, nickel, cobalt, yttrium, and bismuth, and placed on the cylindrical surface of the mercury target at the distance of 15 - 16 cm from the beam-incident-surface of the target. Disintegration rates of induced radioactivities were measured at several cooling-time ranging from hours to months. The principal nuclides contributing to the radioactivity were pointed out for each material. The experimental results for bismuth were compared with the calculations with DCAHIN-SP code. (author)

  1. Measurements of activation reaction rate distributions on a mercury target bombarded with high-energy protons at AGS

    Energy Technology Data Exchange (ETDEWEB)

    Takada, Hiroshi; Kasugai, Yoshimi; Nakashima, Hiroshi; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ino, Takashi; Kawai, Masayoshi [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan); Jerde, Eric; Glasgow, David [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    2000-02-01

    A neutronics experiment was carried out using a thick mercury target at the Alternating Gradient Synchrotron (AGS) facility of Brookhaven National Laboratory in a framework of the ASTE (AGS Spallation Target Experiment) collaboration. Reaction rate distributions around the target were measured by the activation technique at incident proton energies of 1.6, 12 and 24 GeV. Various activation detectors such as the {sup 115}In(n,n'){sup 115m}In, {sup 93}Nb(n,2n){sup 92m}Nb, and {sup 209}Bi(n,xn) reactions with threshold energies ranging from 0.3 to 70.5 MeV were employed to obtain the reaction rate data for estimating spallation source neutron characteristics of the mercury target. It was found from the measured {sup 115}In(n,n'){sup 115m}In reaction rate distribution that the number of leakage neutrons becomes maximum at about 11 cm from the top of hemisphere of the mercury target for the 1.6-GeV proton incidence and the peak position moves towards forward direction with increase of the incident proton energy. The similar result was observed in the reaction rate distributions of other activation detectors. The experimental procedures and a full set of experimental data in numerical form are summarized in this report. (author)

  2. Measurements of activation reaction rate distributions on a mercury target bombarded with high-energy protons at AGS

    International Nuclear Information System (INIS)

    Takada, Hiroshi; Kasugai, Yoshimi; Nakashima, Hiroshi; Ikeda, Yujiro; Jerde, Eric; Glasgow, David

    2000-02-01

    A neutronics experiment was carried out using a thick mercury target at the Alternating Gradient Synchrotron (AGS) facility of Brookhaven National Laboratory in a framework of the ASTE (AGS Spallation Target Experiment) collaboration. Reaction rate distributions around the target were measured by the activation technique at incident proton energies of 1.6, 12 and 24 GeV. Various activation detectors such as the 115 In(n,n') 115m In, 93 Nb(n,2n) 92m Nb, and 209 Bi(n,xn) reactions with threshold energies ranging from 0.3 to 70.5 MeV were employed to obtain the reaction rate data for estimating spallation source neutron characteristics of the mercury target. It was found from the measured 115 In(n,n') 115m In reaction rate distribution that the number of leakage neutrons becomes maximum at about 11 cm from the top of hemisphere of the mercury target for the 1.6-GeV proton incidence and the peak position moves towards forward direction with increase of the incident proton energy. The similar result was observed in the reaction rate distributions of other activation detectors. The experimental procedures and a full set of experimental data in numerical form are summarized in this report. (author)

  3. Water flow experiments and analyses on the cross-flow type mercury target model with the flow guide plates

    CERN Document Server

    Haga, K; Kaminaga, M; Hino, R

    2001-01-01

    A mercury target is used in the spallation neutron source driven by a high-intensity proton accelerator. In this study, the effectiveness of the cross-flow type mercury target structure was evaluated experimentally and analytically. Prior to the experiment, the mercury flow field and the temperature distribution in the target container were analyzed assuming a proton beam energy and power of 1.5 GeV and 5 MW, respectively, and the feasibility of the cross-flow type target was evaluated. Then the average water flow velocity field in the target mock-up model, which was fabricated from Plexiglass for a water experiment, was measured at room temperature using the PIV technique. Water flow analyses were conducted and the analytical results were compared with the experimental results. The experimental results showed that the cross-flow could be realized in most of the proton beam path area and the analytical result of the water flow velocity field showed good correspondence to the experimental results in the case w...

  4. Gigacycle fatigue behaviour of austenitic stainless steels used for mercury target vessels

    International Nuclear Information System (INIS)

    Naoe, Takashi; Xiong, Zhihong; Futakawa, Masatoshi

    2016-01-01

    A mercury enclosure vessel for the pulsed spallation neutron source manufactured from a type 316L austenitic stainless steel, a so-called target vessel, suffers the cyclic loading caused by the proton beam induced pressure waves. A design criteria of the JSNS target vessel which is defined based on the irradiation damage is 2500 h at 1 MW with a repetition rate of 25 Hz, that is, the target vessel suffers approximately 10 9 cyclic loading while in operation. Furthermore, strain rate of the beam window of the target vessel reaches 50 s −1 at the maximum, which is much higher than that of the conventional fatigue. Gigacycle fatigue strength up to 10 9 cycles for solution annealed 316L (SA) and cold-worked 316L (CW) were investigated through the ultrasonic fatigue tests. Fatigue tests were performed under room temperature and 250 °C which is the maximum temperature evaluated at the beam window in order to investigate the effect of temperature on fatigue strength of SA and CW 316L. The results showed that the fatigue strength at 250 °C is clearly reduced in comparison with room temperature, regardless of cold work level. In addition, residual strength and microhardness of the fatigue tested specimen were measured to investigate the change in mechanical properties by cyclic loading. Cyclic hardening was observed in both the SA and CW 316L, and cyclic softening was observed in the initial stage of cyclic loading in CW 316L. Furthermore, abrupt temperature rising just before fatigue failure was observed regardless of testing conditions.

  5. miR-200bc/429 cluster alleviates inflammation in IgA nephropathy by targeting TWEAK/Fn14.

    Science.gov (United States)

    Guo, Yong; Liao, Yuanjiang

    2017-11-01

    Immunoglobulin A nephropathy (IgAN) is one of the most common glomerular diseases worldwide. Various studies have identified a host of microRNAs (miRNAs) abnormally expressed in IgAN and might affect the pathogenesis and progression of IgAN. However, miR-200bc/429 cluster in the pathopoiesis of IgAN remains poorly understood. For this study, we found that miR-200bc/429 cluster is downregulated in IgAN tissues and IgAN podocytes and HK2 cells compared with their matched controls respectively. In addition, overexpression of miR-200bc/429 cluster in IgAN podocytes and HK2 cells could attenuate the release of inflammatory cytokines MCP-1, IL-6 and RANTES. Moreover, the 3' untranslated region (UTR) of TNF-like weak inducer of apoptosis (TWEAK) was identified to be a direct target of miR-200bc/429 cluster. Furthermore, our results showed that miR-200bc/429 cluster can inhibit TWEAK mediated NF-κB pathway activation in IgAN. Overall, our findings revealed that miR-200bc/429 cluster alleviates inflammation in IgAN through TWEAK/Fn14 system and might serve as a biomarker as well as a promising therapeutic target for IgAN. Copyright © 2017. Published by Elsevier B.V.

  6. Pressure and stress waves in a spallation neutron source mercury target generated by high-power proton pulses

    CERN Document Server

    Futakawa, M; Conrad, H; Stechemesser, H

    2000-01-01

    The international ASTE collaboration has performed a first series of measurements on a spallation neutron source target at the Alternating Gradient Synchrotron (AGS) in Brookhaven. The dynamic response of a liquid mercury target hit by high-power proton pulses of about 40 ns duration has been measured by a laser Doppler technique and compared with finite elements calculations using the ABAQUS code. It is shown that the calculation can describe the experimental results for at least the time interval up to 100 mu s after the pulse injection. Furthermore, it has been observed that piezoelectric pressure transducers cannot be applied in the high gamma-radiation field of a spallation target.

  7. Foil analysis of 1.5-GeV proton bombardment of a mercury target

    CERN Document Server

    Charlton, L A; Glasgow, D C; Gabriel, T A

    1999-01-01

    The number of reactant nuclei in a series of foils surrounding a container of mercury that has been bombarded by 1.5-GeV protons is calculated and compared with experimental measurements. This procedure is done to aid in the validation of the mercury cross sections used in the design studies of the Spallation Neutron Source (SNS). It is found that the calculations match the measurements to within the uncertainties inherent in the analysis.

  8. Manufacturing and supply of a mercury cooled rotary uranium target for the GELINA accelerator facility of IRMM

    International Nuclear Information System (INIS)

    Febvre, M.

    2009-01-01

    AREVA CERCA is a manufacturer of Uranium fuel elements for Research Reactors, Mechanical Components for nuclear industry and Radioactive Reference Sources for nuclear industry and medicine. The GELINA high-resolution neutron time-of-flight measurements facility of IRMM (Institute for Reference Materials and Measurements) operates with a very special Uranium target. There is no other neutron production target in the world that has the same or even similar characteristics. Over more than two decades, AREVA CERCA developed and manufactured the rotary Uranium targets for the GELINA facility of IRMM. The use of Uranium and the induced activation during operation in GELINA ask for extremely reliable equipment, responding to very high safety demands. For the fabrication of the target, the very high quality control standards applicable for the fabrication of nuclear equipment must be applied. The material of the Uranium-molybdenum disk must fulfill very restrictive conditions. The target core of the target is cooled by a stream of Mercury, pumped by an electromagnetic pump manufactured by AREVA CERCA. Temperatures in the Uranium disk must be measured with thermocouples distributed inside the Uranium core, at the Uranium/cladding interface and at the inlet and outlet of the Mercury. The target has to rotate between an upper and a lower neutron moderator with very severe geometrical tolerances. The very small gap between the Uranium and the cladding must be filled with Helium before sealing. Preparation and installation of the Target at the GELINA linear Accelerator is presented. Performances and reliability of the targets are reported combined with major experiences and results gained by IRMM. (author)

  9. Vaporization of mercury from molten lead droplets doped with mercury: Pb/Hg source term experiment for the APT/SILC target

    International Nuclear Information System (INIS)

    Tutu, N.K.; Greene, G.A.

    1994-09-01

    Experiments were performed to measure the fraction of mercury inventory released when droplets of molten lead, doped with a known concentration of mercury, fall through a controlled environment. The temperature of molten droplets ranged from 335 C to 346 C, and the concentration of mercury in the droplets ranged from 0.2 mass % to 1.0 mass %. The environment consisted of an air stream, at a temperature nominally equal to the melt temperature, and moving vertically upwards at a velocity of 10 cm/s. Direct observations and chemical analysis showed that no mercury was released from the molten droplets. Based upon the experimental results, it is concluded that no mercury vapor is likely to be released from the potentially molten source rod material in the APT-SILC Neutron Source Array to the confinement atmosphere during a postulated Large Break Loss Of Coolant Accident scenario leading to the melting of a fraction of the source rods

  10. MiR-200c increases the radiosensitivity of non-small-cell lung cancer cell line A549 by targeting VEGF-VEGFR2 pathway.

    Directory of Open Access Journals (Sweden)

    Liangliang Shi

    Full Text Available MicroRNAs (miRNAs have been demonstrated to participate in many important cellular processes including radiosensitization. VEGF family, an important regulator of angiogenesis, also plays a crucial role in the regulation of cancer cell radiosensitivity. VEGFR2 mediates the major growth and permeability actions of VEGF in a paracrine/autocrine manner. MiR-200c, at the nexus of epithelial-mesenchymal transition (EMT, is predicted to target VEGFR2. The purpose of this study is to test the hypothesis that regulation of VEGFR2 pathway by miR-200c could modulate the radiosensitivity of cancer cells. Bioinformatic analysis, luciferase reporter assays and biochemical assays were carried out to validate VEGFR2 as a direct target of miR-200c. The radiosensitizing effects of miR-200c on A549 cells were determined by clonogenic assays. The downstream regulating mechanism of miR-200c was explored with western blotting assays, FCM, tube formation assays and migration assays. We identified VEGFR2 as a novel target of miR-200c. The ectopic miR-200c increased the radiosensitivity of A549 while miR-200c down-regulation decreased it. Besides, we proved that miR-200c radiosensitized A549 cells by targeting VEGF-VEGFR2 pathway specifically, thus leading to inhibition of its downstream pro-survival signaling transduction and angiogenesis, and serves as a potential target for radiosensitizition research.

  11. Trace-level mercury removal from surface water

    International Nuclear Information System (INIS)

    Klasson, K.T.; Bostick, D.T.

    1998-01-01

    Many sorbents have been developed for the removal of mercury and heavy metals from waters; however, most of the data published thus far do not address the removal of mercury to the target levels represented in this project. The application to which these sorbents are targeted for use is the removal of mercury from microgram-per-liter levels to low nanogram-per-liter levels. Sorbents with thiouronium, thiol, amine, sulfur, and proprietary functional groups were selected for these studies. Mercury was successfully removed from surface water via adsorption onto Ionac SR-4 and Mersorb resins to levels below the target goal of 12 ng/L in batch studies. A thiol-based resin performed the best, indicating that over 200,000 volumes of water could be treated with one volume of resin. The cost of the resin is approximately $0.24 per 1,000 gal of water

  12. Mercury's Messenger

    Science.gov (United States)

    Chapman, Clark R.

    2004-01-01

    Forty years after Mariner 2, planetary exploration has still only just begun, and many more missions are on drawing boards, nearing the launch pad, or even en route across interplanetary space to their targets. One of the most challenging missions that will be conducted this decade is sending the MESSENGER spacecraft to orbit the planet Mercury.…

  13. Water flow experiment using the PIV technique and the thermal hydraulic analysis on the cross-flow type mercury target model

    International Nuclear Information System (INIS)

    Haga, Katsuhiro; Terada, Atsuhiko; Kaminaga, Masanori; Hino, Ryutaro

    2001-01-01

    In this study the effectiveness of the cross-flow type mercury target structure was evaluated experimentally and analytically. The average water flow velocity field in the target mock-up model, which was fabricated with plexiglass, was measured at room temperature using the PIV (Particle Image Velocimetry) technique. The water flow analyses were conducted and the analytical results were compared with the experimental results. The experimental results showed that the cross-flow could be realized in the former part of the proton beam path where the heat load by the spallation reaction is large, and the analytical result of the water flow velocity field showed good correspondence to the experimental result in the case of the Reynolds number of more than 4.83 x 10 5 at the model inlet. With these results, the effectiveness of the cross-flow type mercury target structure and the present analysis code system was demonstrated. Then the mercury flow field and the temperature distribution in the target container were analyzed assuming the proton beam energy and power of 3 GeV and 5 MW. The analytical result showed that the cross-flow field of mercury, which is similar to the water flow field, could also be attained. (author)

  14. MicroRNA-200a-3p suppresses tumor proliferation and induces apoptosis by targeting SPAG9 in renal cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xinsheng; Jiang, Fuquan; Song, Haitao; Li, Xu; Xian, Jiantao; Gu, Xinquan, E-mail: guxqprofessor@163.com

    2016-02-12

    Sperm-associated antigen 9(SPAG9), as a well-recognized oncogene protein, has a critical effect on renal cell carcinoma (RCC) progression. Our study tried to explore the mediator of miR-200a-3p, a tumor suppressing miRNA on SPAG9 expression and renal cell proliferation and apoptosis. We found the expression of miR-200a-3p was significantly lower in RCC specimens. Based on in vitro assays, we found miR-200a-3p significantly inhibit cancer cell proliferation by inducing apoptosis. In addition, our study uncovered that miR-200a-3p directly regulates oncogenic SPAG9 in 786-O and ACHN cells. Silencing of SPAG9 resulted in significantly decreased in the growth and the cell cycle of the renal cancer cell lines. Understanding of oncogenic SPAG9 regulated by miR-200a-3p might be beneficial to reveal new therapeutic targets for RCC. - Highlights: • MiR-200a-3p is downregulated in renal cell carcinoma. • MiR-200a-3p regulates cell proliferation through inducing apoptosis. • MiR-200a-3p is involved in cell cycle regulation. • SPAG9 is a potential target of miR-200a-3p.

  15. Water flow experiment using the PIV technique and the thermal hydraulic analysis on the cross-flow type mercury target model with the blade flow distributors

    International Nuclear Information System (INIS)

    Haga, Katsuhiro; Terada, Atsuhiko; Kaminaga, Masanori; Hino, Ryutaro

    2000-01-01

    The flow patterns in the mock-up model of the cross-flow type mercury target were measured using the PIV (particle image velocimetry) technique under water flow conditions at room temperature. The experimental results were compared with the analytical results conducted with the thermal hydraulic analysis code, STAR-CD. As a result, it was confirmed experimentally that the cross-flow could be realized in most of the proton beam path area, where the removal of the high density heat is important, with the proper flow rate distribution along the proton beam path. The analytical result showed the good correspondence to the experimental result. Then the mercury flow field and the temperature distribution were analyzed taking the volumetric heat generation by the spallation reaction into consideration. The volumetric heat generation calculated for the proton beam energy and power of 1.5 GeV and 5 MW were assumed in the analysis. The mercury flow analysis showed that the maximum mercury temperature less than the design criteria of 300degC can be attained with the inlet mercury velocity of more than 1.1 m/s and that the recirculation flow seen in the rear of the proton beam path is considered to cause no excessive temperature rise. (author)

  16. Mercury balance analysis

    International Nuclear Information System (INIS)

    Maag, J.; Lassen, C.; Hansen, E.

    1996-01-01

    A detailed assessment of the consumption of mercury, divided into use areas, was carried out. Disposal and emissions to the environment were also qualified. The assessment is mainly based on data from 1992 - 1993. The most important source of emission of mercury to air is solid waste incineration which is assessed in particular to be due to the supply of mercury in batteries (most likely mercury oxide batteries from photo equipment) and to dental fillings. The second most important source of mercury emission to air is coal-fired power plants which are estimated to account for 200-500 kg of mercury emission p.a. Other mercury emissions are mainly related to waste treatment and disposal. The consumption of mercury is generally decreasing. During the period from 1982/83 - 1992-93, the total consumption of mercury in Denmark was about halved. This development is related to the fact that consumption with regard to several important use areas (batteries, dental fillings, thermometers etc.) has been significantly reduced, while for other purposes the use of mercury has completely, or almost disappeared, i.e. (fungicides for seed, tubes etc.). (EG)

  17. Fragmentation and lateral scattering of 120 and 200 MeV/u {sup 4}He ions in water targets

    Energy Technology Data Exchange (ETDEWEB)

    Rovituso, Marta

    2016-06-02

    Along with an increased popularity of heavy ions in cancer therapy, {sup 4}He ions have regained the interest of the medical community as a compromise between protons and {sup 12}C ions. Although 2054 patients have been treated with {sup 4}He beams at Lawrence Berkeley Laboratory (LBL) (Berkeley CA, US) between 1975 and 1992, a comprehensive database of biological and physics measurements in the therapeutic energy range is still missing. One of the first steps necessary for introducing {sup 4}He ions in particle therapy, is the development of a dedicated treatment planning system, for which basic physics information such as the characterization of the beam lateral scattering and fragmentation cross sections describing the loss of primary particles and the build up of secondary fragments are required. Examination of data found in the literature reveals a gap in the therapeutic energy range. These measurements are essential for benchmarking not only the new model developed for the in-house treatment planning code TRiP98 (Treatment Planning for Particles), but also for already existing beam algorithms and for Monte Carlo codes like Geant4 and Fluka. The aim of this work is to provide fragmentation cross sections of {sup 4}He ions in the therapeutic energy range. The experimental data presented here were measured at Heidelberg Ion Beam Therapy Center (HIT) (Heidelberg, Germany) using 120 MeV/u and 200 MeV/u {sup 4}He beams. The attenuation of 200 MeV/u {sup 4}He beam in water was studied together with the build up of the secondary fragments produced by nuclear fragmentation processes. Target thicknesses between 1 and 25 cm H{sub 2}O were chosen to investigate nuclear fragmentation also beyond the maximum penetration depth of the {sup 4}He ions. The mixed radiation field produced by the interaction of 120 and 200 {sup 4}He ions with water targets (4.28 and 13.96 cm thick, respectively) has also been investigated in this work by measuring double differential cross

  18. Sulforaphane targets cancer stemness and tumor initiating properties in oral squamous cell carcinomas via miR-200c induction.

    Science.gov (United States)

    Liu, Chia-Ming; Peng, Chih-Yu; Liao, Yi-Wen; Lu, Ming-Yi; Tsai, Meng-Lun; Yeh, Jung-Chun; Yu, Chuan-Hang; Yu, Cheng-Chia

    2017-01-01

    Cancer stem cells (CSCs) are deemed as the driving force of tumorigenesis in oral squamous cell carcinomas (OSCCs). In this study, we investigated the chemotherapeutic effect of sulforaphane, a dietary component from broccoli sprouts, on targeting OSCC-CSCs. The effect of sulforaphane on normal oral epithelial cells (SG) and sphere-forming OSCC-CSCs isolated from SAS and GNM cells was examined. ALDH1 activity and CD44 positivity of OSCC-CSCs with sulforaphane treatment was assessed by flow cytometry analysis. In vitro and in vivo tumorigenicity assays of OSCC-CSCs with sulforaphane treatment were presented. We observed that the sulforaphane dose-dependently eliminated the proliferation rate of OSCC-CSCs, whereas the inhibition on SG cells proliferation was limited. Cancer stemness properties including self-renewal, CD44 positivity, and ALDH1 activity were also decreased in OSCC-CSCs with different doses of sulforaphane treatment. Moreover, sulforaphane treatment of OSCC-CSCs decreased the migration, invasion, clonogenicity, and in vivo tumorigenicity of xenograghts. Sulforaphane treatment resulted in a dose-dependent increase in the levels of tumor suppressive miR200c. These lines of evidence suggest that sulforaphane can suppress the cancer stemness and tumor-initiating properties in OSCC-CSCs both in vitro and in vivo. Copyright © 2016. Published by Elsevier B.V.

  19. Measurement of activation reaction rate distribution on a mercury target with a lead-reflector and light-water-moderator for high energy proton bombardment using AGS accelerator

    International Nuclear Information System (INIS)

    Kasugai, Yoshimi; Takada, Hiroshi; Meigo, Shin-ichiro

    2001-02-01

    Characteristic of spallation neutrons driven by GeV protons from a mercury target with a lead-reflector and light-water-moderator was studied experimentally using the Alternating Gradient Synchrotron (AGS) facility of Brookhaven National Laboratory in a framework of the ASTE (AGS Spallation Target Experiment) collaboration. Several reaction rates along with the mercury target were measured with the activation method at incident proton energies of 1.94, 12 and 24 GeV. Indium, niobium, aluminum, cobalt, nickel and bismuth were used as activation detectors to cover the threshold energy of between 0.33 and 40.9 MeV. This report summarizes the experimental procedure with all the measured data. (author)

  20. Adaption and use of a quadcopter for targeted sampling of gaseous mercury in the atmosphere.

    Science.gov (United States)

    Black, Oscar; Chen, Jingjing; Scircle, Austin; Zhou, Ying; Cizdziel, James V

    2018-03-22

    We modified a popular and inexpensive quadcopter to collect gaseous mercury (Hg) on gold-coated quartz cartridges, and analyzed the traps using cold vapor atomic fluorescence spectrometry. Flight times averaged 16 min, limited by battery life, and yielded > 5 pg of Hg, well above the limit of detection (quadcopter, we measured atmospheric Hg near anthropogenic emission sources in the mid-south USA, including a municipal landfill, coal-fired power plant (CFPP), and a petroleum refinery. Average concentrations (± standard deviation) immediately downwind of the landfill were higher at ground level and 30 m compared to 60 and 120 m (5.3 ± 0.5 ng m -3 , 5.4 ± 0.7 ng m -3 , 4.2 ± 0.7 ng m -3 , and 2.5 ± 0.3 ng m -3 , respectively). Concentrations were also higher at an urban/industrial area (Memphis) (3.3 ± 0.9 ng m -3 ) compared with a rural/background area (1.5 ± 0.2 ng m -3 ). Due to airspace flight restrictions near the CFPP and refinery, we were unable to access near-field (stack) plumes and did not observe differences between upwind and downwind locations. Overall, this study demonstrates that highly maneuverable multicopters can be used to probe Hg concentrations aloft, which may be particularly useful for evaluating Hg emissions from remote landscapes and transient sources that are inadequately characterized and leading to uncertainties in ecosystem budgets.

  1. Targeted delivery of miR-200c/DOC to inhibit cancer stem cells and cancer cells by the gelatinases-stimuli nanoparticles.

    Science.gov (United States)

    Liu, Qin; Li, Ru-Tian; Qian, Han-Qing; Wei, Jia; Xie, Li; Shen, Jie; Yang, Mi; Qian, Xiao-Ping; Yu, Li-Xia; Jiang, Xi-Qun; Liu, Bao-Rui

    2013-09-01

    Cancer stem cells (CSCs) are recently discovered as vital obstacles for the successful cancer therapy. Emerging evidences suggest that miR-200c functions as an effective CSCs inhibitor and can restore sensitivity to microtubule-targeting drugs. In the present work, the intelligent gelatinases-stimuli nanoparticles (NPs) was set up to co-deliver miR-200c and docetaxel (DOC) to verify their synergetic effects on inhibition of CSCs and non-CSC cancer cells. After tumor cells were treated with miR-200c NPs, miR-200c and its targeted gene class III beta-tubulin (TUBB3)TUBB3 expression were evaluated. The effects of miR-200c/DOC NPs on tumor cell viability, migration and invasion as well as the expression of E-cadherin and CD44 were studied. The antitumor effects of miR-200c/DOC NPs were compared with DOC NPs in xenograft gastric cancer mice. Moreover, the residual tumors after treatment were subcutaneously seeded into nude mice to further investigate the effective maintenance of NPs. We found that the gelatinases-stimuli NPs facilitated miR-200c into cells, achieving sustained miR-200c expression in tumor cells during 9 days. The miR-200c/DOC NPs significantly enhanced cytotoxicity of DOC, possibly by decreasing TUBB3 level, and reversing EMT. The miR-200c NPs achieved high levels of in vivo accumulation and long retention in gastric cancer xenografts after intravenous administration. The miR-200c/DOC NPs prominently suppressed in vivo tumor growth with elevated miR-200c and E-cadherin levels and down-regulated TUBB3 and CD44 expressions. When the residual tumors after miR-200c/DOC NPs treatment were re-transplanted into nude mice, the tumors demonstrated the slowest growth speed. The miR-200c/DOC NPs may provide a promising modality for co-delivery of nucleic acid and drugs to simultaneously inhibit CSCs and non-CSC cancer cells. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. miR-200c targets nuclear factor IA to suppress HBV replication and gene expression via repressing HBV Enhancer I activity.

    Science.gov (United States)

    Tian, Hui; He, Zhenkun

    2018-03-01

    Hepatitis B virus (HBV) chronic infection is a health problem in the worldwide, with a underlying higher risk of liver cirrhosis and hepaticocellular carcinoma. A number of studies indicate that microRNAs (miRNAs) play vital roles in HBV replication. This study was designed to explore the potential molecular mechanism of miR-200c in HBV replication. The expression of miR-200c, nuclear factor IA (NFIA) mRNA, HBV DNA, and HBV RNA (pregenomic RNA (pgRNA), and total RNA) were measured by qRCR. The levels of HBsAg and HBeAg were detected by ELISA. NFIA expression at protein level was measured by western blot. The direct interaction between miR-200c and NFIA were identified by Targetscan software and Dual-Luciferase reporter analysis. Enhance I activity were detected by Dual-Luciferase reporter assay. miR-200c expression was prominently reduced in pHBV1.3-tranfected Huh7 and in stable HBV-producing cell line (HepG2.2.15). The enforced expression of miR-200c significantly suppressed HBV replication, as demonstrated by the reduced levels of HBV protein (HBsAg and HBeAg) and, DNA and RNA (pgRNA and total RNA) levels. NFIA was proved to be a target of miR-200c and NFIA overexpression notably stimulated HBV replication. In addition, the inhibitory effect of miR-200c on HBV Enhance I activity was abolished following restoration of NFIA. miR-200c repressed HBV replication by directly targeting NFIA, which might provide a novel therapeutic target for HBV infection. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  3. Decreased MiR-200a/141 Suppress Cell Migration and Proliferation by Targeting PTEN in Hirschsprung's Disease

    Directory of Open Access Journals (Sweden)

    Hongxing Li

    2014-08-01

    Full Text Available Background/Aims: Hirschsprung's disease (HSCR is a genetic disorder of neural crest development. In this study, we investigated whether and how miR-200a and miR-141, belonging to miR-200 family, were involved in the pathogenesis of HSCR. Methods: Quantitative real time PCR and Western blot were used to detect the levels of miRNA, mRNAs, and proteins in colon tissues from 88 HSCR patients and 75 controls. The direct regulation of specific mRNA by miRNAs was validated by dual-luciferase reporter assay and RNA interference in cell lines. Transwell assays, CCK8 assay, and flow cytometry were inplemented to measure viability and activities of human 293T and SH-SY5Y cells, respectively. Results: Aberrant suppression of miR-200a was observed in colon tissues of HSCR patients. A decreased level of miR-200a and miR-141 correlated with increased levels of PTEN mRNA and protein. The Dual-Luciferase reporter gene assay demonstrated that miR-200a and miR-141 binded directly to 3'UTR of PTEN and resulting in the inhibition of PTEN. The reductions in miR-200a and miR-141 inhibited migration and proliferation of 293T and SH-SY5Y cells through up-regulating the expression of PTEN. Moreover, knocking-down of PTEN rescued the extent of suppressed cell migration and proliferation induced by miR-200a and miR-141. Conclusions: The miR-200 family may play a crucial role in the pathogenesis of HSCR by co-regulating PTEN.

  4. Brain as a critical target of mercury in environmentally exposed fish (Dicentrarchus labrax)--bioaccumulation and oxidative stress profiles.

    Science.gov (United States)

    Mieiro, C L; Pereira, M E; Duarte, A C; Pacheco, M

    2011-06-01

    Although mercury is recognized as a potent neurotoxicant, information regarding its threat to fish brain and underlying mechanisms is still scarce. In accordance, the objective of this work was to assess vulnerability of fish to mercury neurotoxicity by evaluating brain pro-oxidant status in wild European sea bass (Dicentrarchus labrax) captured in an estuarine area affected by chlor-alkali industry discharges (Laranjo Basin, Ria de Aveiro, Portugal). To achieve this goal, brain antioxidant responses such as catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST) activities and total glutathione (GSHt) content were measured. Additionally, damage was determined as lipid peroxidation. To ascertain the influence of seasonal variables on both mercury accumulation and oxidative stress profiles, surveys were conducted in contrasting conditions-warm and cold periods. In the warm period, brain of fish from mercury contaminated sites exhibited ambivalent antioxidant responses, viz. higher GR activity and lower CAT activity regarded, respectively, as possible signs of protective adaptation and increased susceptibility to oxidative stress challenge. Though the risk of an overwhelming ROS production cannot be excluded, brain appeared to possess compensatory mechanisms and was able to avoid lipid peroxidative damage. The warm period was the most critical for the appearance of oxidative damage as no inter-site alterations on oxidative stress endpoints were detected in the cold period. Since seasonal differences were found in oxidative stress responses and not in mercury bioaccumulation, environmental factors affected the former more than the latter. This work increases the knowledge on mercury neurotoxicity in feral fish, highlighting that the definition of critical tissue concentrations depends on environmental variables. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Sulforaphane targets cancer stemness and tumor initiating properties in oral squamous cell carcinomas via miR-200c induction

    OpenAIRE

    Chia-Ming Liu; Chih-Yu Peng; Yi-Wen Liao; Ming-Yi Lu; Meng-Lun Tsai; Jung-Chun Yeh; Chuan-Hang Yu; Cheng-Chia Yu

    2017-01-01

    Background/Purpose: Cancer stem cells (CSCs) are deemed as the driving force of tumorigenesis in oral squamous cell carcinomas (OSCCs). In this study, we investigated the chemotherapeutic effect of sulforaphane, a dietary component from broccoli sprouts, on targeting OSCC-CSCs. Methods: The effect of sulforaphane on normal oral epithelial cells (SG) and sphere-forming OSCC-CSCs isolated from SAS and GNM cells was examined. ALDH1 activity and CD44 positivity of OSCC-CSCs with sulforaphane t...

  6. Mercury and Your Health

    Science.gov (United States)

    ... the Risk of Exposure to Mercury Learn About Mercury What is Mercury What is Metallic mercury? Toxicological Profile ToxFAQs Mercury Resources CDC’s National Biomonitoring Program Factsheet on Mercury ...

  7. Implementing an intensified antibiotic stewardship programme targeting cephalosporin and fluoroquinolone use in a 200-bed community hospital in Germany.

    Science.gov (United States)

    Borde, J P; Litterst, S; Ruhnke, M; Feik, R; Hübner, J; deWith, K; Kaier, K; Kern, W V

    2015-02-01

    Prescription of third-generation cephalosporins and fluoroquinolones has been linked to an increasing incidence of gram-negative bacteria producing extended-spectrum beta-lactamases, methicillin-resistant Staphylococcus aureus and nosocomial infection with Clostridium difficile. Antibiotic stewardship (ABS) programmes offer evidence-based tools to control antibiotic prescription rates and thereby influence the incidence of nosocomial infection and contain the development of multidrug-resistant bacteria, but there is limited experience with such programmes at community hospitals. We implemented an ABS programme at a 200-bed community hospital and aimed at a > 30 % reduction of cephalosporin and fluoroquinolone consumption within 1 year. Pharmacy data were obtained to estimate hospital-wide drug use density expressed in WHO-ATC-defined daily doses (DDD) or hospital-adapted recommended daily doses (RDD) per 1,000 patient days. The effect of the ABS intervention on drug use density was analysed using interrupted time-series analysis for the periods between January 2011 and March 2013 as pre-intervention, and between April 2013 and March 2014 as post-intervention period. The CDI incidence was calculated based on microbiology laboratory data. Cephalosporin use (measured in RDD/1,000 patient days) decreased by 33 %, and fluoroquinolone use decreased by 31 %, respectively. Interrupted time-series analysis confirmed significant changes in the drug use density trends for both cephalosporins and fluoroquinolones after the intervention as well as for total antibiotic use that decreased by 11 % while no significant effect was noted for CDI incidence rates. ABS programmes can be effective in community hospitals and may help establish ecologically advantageous antibiotic strategies when needed.

  8. Rebmab200, a Humanized Monoclonal Antibody Targeting the Sodium Phosphate Transporter NaPi2b Displays Strong Immune Mediated Cytotoxicity against Cancer: A Novel Reagent for Targeted Antibody Therapy of Cancer

    Science.gov (United States)

    dos Santos, Mariana Lopes; Yeda, Fernanda Perez; Tsuruta, Lilian Rumi; Horta, Bruno Brasil; Pimenta, Alécio A.; Degaki, Theri Leica; Soares, Ibere C.; Tuma, Maria Carolina; Okamoto, Oswaldo Keith; Alves, Venancio A. F.; Ritter, Gerd; Moro, Ana Maria

    2013-01-01

    NaPi2b, a sodium-dependent phosphate transporter, is highly expressed in ovarian carcinomas and is recognized by the murine monoclonal antibody MX35. The antibody had shown excellent targeting to ovarian cancer in several early phase clinical trials but being murine the antibody's full therapeutic potential could not be explored. To overcome this impediment we developed a humanized antibody version named Rebmab200, expressed in human PER.C6® cells and cloned by limiting dilution. In order to select a clone with high therapeutic potential clones were characterized using a series of physicochemical assays, flow cytometry, real-time surface plasmon resonance, glycosylation analyses, immunohistochemistry, antibody-dependent cell-mediated cytotoxicity, complement-dependent-cytotoxicity assays and quantitative PCR. Comparative analyses of Rebmab200 and MX35 monoclonal antibodies demonstrated that the two antibodies had similar specificity for NaPi2b by flow cytometry with a panel of 30 cell lines and maintained similar kinetic parameters. Robust and high producer cell clones potentially suitable for use in manufacturing were obtained. Rebmab200 antibodies were assessed by immunohistochemistry using a large panel of tissues including human carcinomas of ovarian, lung, kidney and breast origin. An assessment of its binding towards 33 normal human organs was performed as well. Rebmab200 showed selected strong reactivity with the tested tumor types but little or no reactivity with the normal tissues tested confirming its potential for targeted therapeutics strategies. The remarkable cytotoxicity shown by Rebmab200 in OVCAR-3 cells is a significant addition to the traits of stability and productivity displayed by the top clones of Rebmab200. Antibody-dependent cell-mediated toxicity functionality was confirmed in repeated assays using cancer cell lines derived from ovary, kidney and lung as targets. To explore use of this antibody in clinical trials, GMP production of Rebmab

  9. Study of fractal behaviour of target fragments produced in 28Si and 32S emulsion collisions at 14.6 and 200 AGeV

    International Nuclear Information System (INIS)

    Rasool, Mir Hashim; Ahmad, Shafiq; Ahmad, M. Ayaz

    2013-01-01

    The experimental data based on 951 and 380 events of 28 Si-emulsion and 32 S-emulsion interactions at 14.6 and 200 AGeV/c respectively have been analysed to investigate intermittent behaviour and fractal properties of emission spectra of fast and slow target associated particles. The observed increasing trend in the values of fractal moments, Fqcorr and modified Gq-moments with decreasing bin size clearly reflects the evaporation model and gives an evidence for an intermittency pattern of fluctuations. The experimental data have been compared with randomly generated uncorrelated Monte Carlo of 10,000 events to check the presence of the statistical fluctuations in the target fragmentation region

  10. Got Mercury?

    Science.gov (United States)

    Meyers, Valerie E.; McCoy, J. Torin; Garcia, Hector D.; James, John T.

    2009-01-01

    Many of the operational and payload lighting units used in various spacecraft contain elemental mercury. If these devices were damaged on-orbit, elemental mercury could be released into the cabin. Although there are plans to replace operational units with alternate light sources, such as LEDs, that do not contain mercury, mercury-containing lamps efficiently produce high quality illumination and may never be completely replaced on orbit. Therefore, exposure to elemental mercury during spaceflight will remain possible and represents a toxicological hazard. Elemental mercury is a liquid metal that vaporizes slowly at room temperature. However, it may be completely vaporized at the elevated operating temperatures of lamps. Although liquid mercury is not readily absorbed through the skin or digestive tract, mercury vapors are efficiently absorbed through the respiratory tract. Therefore, the amount of mercury in the vapor form must be estimated. For mercury releases from lamps that are not being operated, we utilized a study conducted by the New Jersey Department of Environmental Quality to calculate the amount of mercury vapor expected to form over a 2-week period. For longer missions and for mercury releases occurring when lamps are operating, we conservatively assumed complete volatilization of the available mercury. Because current spacecraft environmental control systems are unable to remove mercury vapors, both short-term and long-term exposures to mercury vapors are possible. Acute exposure to high concentrations of mercury vapors can cause irritation of the respiratory tract and behavioral symptoms, such as irritability and hyperactivity. Chronic exposure can result in damage to the nervous system (tremors, memory loss, insomnia, etc.) and kidneys (proteinurea). Therefore, the JSC Toxicology Group recommends that stringent safety controls and verifications (vibrational testing, etc.) be applied to any hardware that contains elemental mercury that could yield

  11. Target size dependence of relativistic hadron emission from S-32 nuclear collisions at 3.7-A-GeV and 200-A-GeV

    CERN Document Server

    Abdelsalam, A; Hafiz, M E

    2012-01-01

    The behavior of the relativistic hadron (shower particle) multiplicity for (32)S-nucleus interactions is investigated. The experiment is carried out at 3.7A GeV (Dubna energy) and 200A GeV (SPS energy) to search for the incident energy effect on the interactions inside the different emulsion target nuclei. Data are presented in terms of the number of emitted relativistic hadrons in both forward and backward angular zones. The dependence on the target size is presented. For this purpose the statistical events are separated into groups according to the interactions with H, CNO, Em, and AgBr target nuclei. The separation of events, into these groups, is executed based on predictions of Glauber's multiple scattering theory. Features suggestive of a decay mechanism seem to be a characteristic of the backward emission of relativistic hadrons. The results strongly support the assumption that the relativistic hadrons may already be emitted during the de-excitation of the excited target nucleus, in a behavior like tha...

  12. DEVELOPMENT OF ANALYTICAL METHODS FOR THE QUANTIFICATION OF THE CHEMICAL FORMS OF MERCURY AND OTHER TARGET POLLUTANTS IN COAL-FIRED BOILER FLUE GAS

    Energy Technology Data Exchange (ETDEWEB)

    Terence J. McManus, Ph.D.

    1999-06-30

    Since approximately 55% of the electrical power produced in the U. S. is generated by coal-based power utility plants, there is serious concern about the massive amounts of coal combustion products emitted into the atmosphere annually. Furthermore, Title III of the 1990 Clean Air Act Amendments (CAAA) requires the measurement and inventory of a possible 189 hazardous air pollutants (HAPs) from any stationary source producing more than 10 tons per year of any one pollutant or more than 25 tons per year of total pollutants. Although power utilities are not presently included on the list of source categories, the CAAA requires the U. S. Environmental Protection Agency to carry out a study of emissions from electricity generation using fossil fuels. Since many of these HAPs are known to be present in coal derived flue gas, coal-fired electric power utilities may be subject to regulation following these studies if Congress considers it necessary. In a cooperative effort with the U. S. Environmental Protection Agency (EPA), the U. S. Department of Energy (DOE) through its Federal Energy Technology Center (FETC) initiated such a study in 1991. DOE-FETC commissioned five primary contractors to conduct emission studies at eight different coal-fired electric utilities. The eight sites represented a cross section of feed coal type, boiler designs, and particulate and gaseous pollutant control technologies. The major goal of these studies was to determine the sampling and analytical methodologies that could be used efficiently to perform these emission tests while producing representative and reliable emission data. The successful methodology could then be recommended to the EPA for use in compliance testing in the event the regulation of air toxic emissions from coal-fired power plants is implemented. A secondary purpose of the testing was to determine the effectiveness of the control technologies in reducing target hazardous air pollutants. Advanced Technology Systems, Inc

  13. Mercury accumulation plant Cyrtomium macrophyllum and its potential for phytoremediation of mercury polluted sites.

    Science.gov (United States)

    Xun, Yu; Feng, Liu; Li, Youdan; Dong, Haochen

    2017-12-01

    Cyrtomium macrophyllum naturally grown in 225.73 mg kg -1 of soil mercury in mining area was found to be a potential mercury accumulator plant with the translocation factor of 2.62 and the high mercury concentration of 36.44 mg kg -1 accumulated in its aerial parts. Pot experiments indicated that Cyrtomium macrophyllum could even grow in 500 mg kg -1 of soil mercury with observed inhibition on growth but no obvious toxic effects, and showed excellent mercury accumulation and translocation abilities with both translocation and bioconcentration factors greater than 1 when exposed to 200 mg kg -1 and lower soil mercury, indicating that it could be considered as a great mercury accumulating species. Furthermore, the leaf tissue of Cyrtomium macrophyllum showed high resistance to mercury stress because of both the increased superoxide dismutase activity and the accumulation of glutathione and proline induced by mercury stress, which favorited mercury translocation from the roots to the aerial parts, revealing the possible reason for Cyrtomium macrophyllum to tolerate high concentration of soil mercury. In sum, due to its excellent mercury accumulation and translocation abilities as well as its high resistance to mercury stress, the use of Cyrtomium macrophyllum should be a promising approach to remediating mercury polluted soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Basic Information about Mercury

    Science.gov (United States)

    ... Your Environment Contact Us Share Basic Information about Mercury On this page: What is mercury? Emissions of ... Consumer products that traditionally contain mercury What is Mercury? Mercury is a naturally-occurring chemical element found ...

  15. Chemical form matters: differential accumulation of mercury following inorganic and organic mercury exposures in zebrafish larvae.

    Science.gov (United States)

    Korbas, Malgorzata; Macdonald, Tracy C; Pickering, Ingrid J; George, Graham N; Krone, Patrick H

    2012-02-17

    Mercury, one of the most toxic elements, exists in various chemical forms each with different toxicities and health implications. Some methylated mercury forms, one of which exists in fish and other seafood products, pose a potential threat, especially during embryonic and early postnatal development. Despite global concerns, little is known about the mechanisms underlying transport and toxicity of different mercury species. To investigate the impact of different mercury chemical forms on vertebrate development, we have successfully combined the zebrafish, a well-established developmental biology model system, with synchrotron-based X-ray fluorescence imaging. Our work revealed substantial differences in tissue-specific accumulation patterns of mercury in zebrafish larvae exposed to four different mercury formulations in water. Methylmercury species not only resulted in overall higher mercury burdens but also targeted different cells and tissues than their inorganic counterparts, thus revealing a significant role of speciation in cellular and molecular targeting and mercury sequestration. For methylmercury species, the highest mercury concentrations were in the eye lens epithelial cells, independent of the formulation ligand (chloride versusl-cysteine). For inorganic mercury species, in absence of l-cysteine, the olfactory epithelium and kidney accumulated the greatest amounts of mercury. However, with l-cysteine present in the treatment solution, mercuric bis-l-cysteineate species dominated the treatment, significantly decreasing uptake. Our results clearly demonstrate that the common differentiation between organic and inorganic mercury is not sufficient to determine the toxicity of various mercury species.

  16. Chemical Form Matters: Differential Accumulation of Mercury Following Inorganic and Organic Mercury Exposures in Zebrafish Larvae

    Energy Technology Data Exchange (ETDEWEB)

    Korbas, Malgorzata; MacDonald, Tracy C.; Pickering, Ingrid J.; George, Graham N.; Krone, Patrick H. (Saskatchewan)

    2013-04-08

    Mercury, one of the most toxic elements, exists in various chemical forms each with different toxicities and health implications. Some methylated mercury forms, one of which exists in fish and other seafood products, pose a potential threat, especially during embryonic and early postnatal development. Despite global concerns, little is known about the mechanisms underlying transport and toxicity of different mercury species. To investigate the impact of different mercury chemical forms on vertebrate development, we have successfully combined the zebrafish, a well-established developmental biology model system, with synchrotron-based X-ray fluorescence imaging. Our work revealed substantial differences in tissue-specific accumulation patterns of mercury in zebrafish larvae exposed to four different mercury formulations in water. Methylmercury species not only resulted in overall higher mercury burdens but also targeted different cells and tissues than their inorganic counterparts, thus revealing a significant role of speciation in cellular and molecular targeting and mercury sequestration. For methylmercury species, the highest mercury concentrations were in the eye lens epithelial cells, independent of the formulation ligand (chloride versus L-cysteine). For inorganic mercury species, in absence of L-cysteine, the olfactory epithelium and kidney accumulated the greatest amounts of mercury. However, with L-cysteine present in the treatment solution, mercuric bis-L-cysteineate species dominated the treatment, significantly decreasing uptake. Our results clearly demonstrate that the common differentiation between organic and inorganic mercury is not sufficient to determine the toxicity of various mercury species.

  17. Mercury Emission Control Technologies for PPL Montana-Colstrip Testing

    Energy Technology Data Exchange (ETDEWEB)

    John P. Kay; Michael L. Jones; Steven A. Benson

    2007-04-01

    technique at Colstrip is not seen. All the additives injected resulted in some reduction in mercury emissions. However, the target reduction of 55% was not achieved. The primary reason for the lower removal rates is because of the lower levels of mercury in the flue gas stream and the lower capture level of fine particles by the scrubbers (relative to that for larger particles). The reaction and interaction of the SEA materials is with the finer fraction of the fly ash, because the SEA materials are vaporized during the combustion or reaction process and condense on the surfaces of entrained particles or form very small particles. Mercury will have a tendency to react and interact with the finer fraction of entrained ash and sorbent as a result of the higher surface areas of the finer particles. The ability to capture the finer fraction of fly ash is the key to controlling mercury. Cost estimates for mercury removal based on the performance of each sorbent during this project are projected to be extremely high. When viewed on a dollar-per-pound-of-mercury removed basis activated carbon was projected to cost nearly $1.2 million per pound of mercury removed. This value is roughly six times the cost of other sorbent-enhancing agents, which were projected to be closer to $200,000 per pound of mercury removed.

  18. Multi-weight isotherm results for mercury removal in upper East Fork Popular Creek water

    International Nuclear Information System (INIS)

    Bostick, D.A.; Klasson, K.T.

    1998-02-01

    Many sorbents have been developed for the removal of mercury and heavy metals from waters; however, the majority of data published to date do not address the removal of mercury to the target levels represented in this project. The application to which these sorbents are targeted for use is the removal of mercury from microgram-per-liter levels to low nanogram-per-liter levels. Sorbents with thiouronium, thiol, amine, sulfur, and proprietary functional groups were selected for these studies. The initial mercury content in the majority of the batch samples was significantly augmented so that the equilibrium concentration was similar to that found in the original stream sample for at least one sample. Mercury was successfully removed from actual water via adsorption onto Ionac SR-4 (by Sybron Chemicals, Inc.), Keyle:X (by SolmeteX), and Mersorb (by Nucon International, Inc.) resins to levels below the target goal of 12 ng/L. A thiol-based resin (Ionac SR-4) performed the best, indicating that over 200,000 volumes of water could be treated with one volume of resin. The cost of the resin is approximately $0.24 per 1000 gal of water

  19. Human Exposure and Health Effects of Inorganic and Elemental Mercury

    Science.gov (United States)

    Zheng, Wei

    2012-01-01

    Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety. PMID:23230464

  20. Mercury flow experiments. 4th report: Measurements of erosion rate caused by mercury flow

    International Nuclear Information System (INIS)

    Kinoshita, Hidetaka; Kaminaga, Masanori; Haga, Katsuhiro; Hino, Ryutaro

    2002-06-01

    The Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting a construction plan of the Material-Life Science Facility, which is consisted of a Muon Science Facility and a Neutron Scattering Facility, in order to open up the new science fields. The Neutron Scattering Facility will be utilized for advanced fields of Material and Life science using high intensity neutron generated by the spallation reaction of a 1 MW pulsed proton beam and mercury target. Design of the spallation mercury target system aims to obtain high neutron performance with high reliability and safety. Since the target system is using mercury as the target material and contains large amount of radioactive spallation products, it is necessary to estimate reliability for strength of instruments in a mercury flow system during lifetime of the facility. Piping and components in the mercury flow system would be damaged by erosion with mercury flow, since these components will be weak by thickness decreasing. This report presents experimental results of wall thickness change by erosion using a mercury experimental loop. In the experiments, an erosion test section and coupons were installed in the mercury experimental loop, and their wall thickness was measured with an ultra sonic thickness gage after every 1000 hours. As a result, under 0.7 m/s of mercury velocity condition which is slightly higher than the practical velocity in mercury pipelines, the erosion is about 3 μm in 1000 hours. The wall thickness decrease during facility lifetime of 30 years is estimated to be less than 0.5 mm. According to the experimental result, it is confirmed that the effect of erosion on component strength is extremely small. Moreover, a measurement of residual mercury on the piping surface was carried out. As a result, 19 g/m 2 was obtained as the residual mercury for the piping surface. According to this result, estimated amount of residual mercury for

  1. Mercury and Pregnancy

    Science.gov (United States)

    ... Home > Pregnancy > Is it safe? > Mercury and pregnancy Mercury and pregnancy E-mail to a friend Please ... vision problems. How can you be exposed to mercury? Mercury has several forms: It can be a ...

  2. Mercury flow experiments. 4th report Measurements of erosion rate caused by mercury flow

    CERN Document Server

    Kinoshita, H; Hino, R; Kaminaga, M

    2002-01-01

    The Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting a construction plan of the Material-Life Science Facility, which is consisted of a Muon Science Facility and a Neutron Scattering Facility, in order to open up the new science fields. The Neutron Scattering Facility will be utilized for advanced fields of Material and Life science using high intensity neutron generated by the spallation reaction of a 1 MW pulsed proton beam and mercury target. Design of the spallation mercury target system aims to obtain high neutron performance with high reliability and safety. Since the target system is using mercury as the target material and contains large amount of radioactive spallation products, it is necessary to estimate reliability for strength of instruments in a mercury flow system during lifetime of the facility. Piping and components in the mercury flow system would be damaged by erosion with mercury flow, since these components will be we...

  3. Mercury emission from crematories in Japan

    Directory of Open Access Journals (Sweden)

    M. Takaoka

    2010-04-01

    Full Text Available Anthropogenic sources of mercury emissions have a significant impact on global pollution. Therefore, finding uncharacterised sources and assessing the emissions from these sources are important. However, limited data are available worldwide on mercury emissions from crematories. In Japan, 99.9% of dead bodies are cremated, which is the highest percentage in the world, and more than 1600 crematories are in operation. We thus focused on emissions from crematories in Japan. The number of targeted facilities was seven, and we used continuous emission monitoring to measure the mercury concentrations and investigate mercury behaviour. The total mercury concentrations in stack gases were a few μg/Nm3 (normal cubic meters. Considering the time profile of mercury and its species in cremations, the findings confirmed that the mercury in stack gas originated from dental amalgam. The amount of mercury emissions was calculated using the total concentration and gas flow rate. Furthermore, the annual amount of mercury emission from crematories in Japan was estimated by using the total number of corpses. The emission amount was considerably lower than that estimated in the United Kingdom. From statistical analyses on population demographics and measurements, future total emissions from crematories were also predicted. As a result, the amount of mercury emitted by crematories will likely increase by 2.6-fold from 2007 to 2037.

  4. Mercury toxicity and neurodegenerative effects.

    Science.gov (United States)

    Carocci, Alessia; Rovito, Nicola; Sinicropi, Maria Stefania; Genchi, Giuseppe

    2014-01-01

    Mercury is among the most toxic heavy metals and has no known physiological role in humans. Three forms of mercury exist: elemental, inorganic and organic. Mercury has been used by man since ancient times. Among the earliest were the Chinese and Romans, who employed cinnabar (mercury sulfide) as a red dye in ink (Clarkson et al. 2007). Mercury has also been used to purify gold and silver minerals by forming amalgams. This is a hazardous practice, but is still widespread in Brazil's Amazon basin, in Laos and in Venezuela, where tens of thousands of miners are engaged in local mining activities to find and purify gold or silver. Mercury compounds were long used to treat syphilis and the element is still used as an antiseptic,as a medicinal preservative and as a fungicide. Dental amalgams, which contain about 50% mercury, have been used to repair dental caries in the U.S. since 1856.Mercury still exists in many common household products around the world.Examples are: thermometers, barometers, batteries, and light bulbs (Swain et al.2007). In small amounts, some organo mercury-compounds (e.g., ethylmercury tiosalicylate(thimerosal) and phenylmercury nitrate) are used as preservatives in some medicines and vaccines (Ballet al. 2001).Each mercury form has its own toxicity profile. Exposure to Hg0 vapor and MeHg produce symptoms in CNS, whereas, the kidney is the target organ when exposures to the mono- and di-valent salts of mercury (Hg+ and Hg++, respectively)occur. Chronic exposure to inorganic mercury produces stomatitis, erethism and tremors. Chronic MeHg exposure induced symptoms similar to those observed in ALS, such as the early onset of hind limb weakness (Johnson and Atchison 2009).Among the organic mercury compounds, MeHg is the most biologically available and toxic (Scheuhammer et a!. 2007). MeHg is neurotoxic, reaching high levels of accumulation in the CNS; it can impair physiological function by disrupting endocrine glands (Tan et a!. 2009).The most

  5. Molecular Mechanism of MicroRNA-200c Regulating Transforming Growth Factor-β (TGF-β)/SMAD Family Member 3 (SMAD3) Pathway by Targeting Zinc Finger E-Box Binding Homeobox 1 (ZEB1) in Hypospadias in Rats.

    Science.gov (United States)

    Qian, Chong; Dang, Xiangyang; Wang, Xianglin; Xu, Wei; Pang, Guijian; Chen, Yifeng; Liu, Chengbei

    2016-10-29

    BACKGROUND The aim of this study was to explore effects of microRNA-200c regulating TGF-β/Smad3 pathway by targeting Zeb1 on the occurrence and development of hypospadias and to evaluate the relationship between microRNA-200c and occurrence of hypospadias. MATERIAL AND METHODS Pregnant rats with a gestational age of 12 days were allocated into 2 groups; one received gavage of DEHP-contained soybean oil (1 ml/day, 8 days; Group A) and the other had gavage of normal soybean oil (1 ml/day, 8 days; Group B). Baby rats with hypospadias from Group A were assigned to the model group (n=20) and healthy baby rats from Group B were assigned to the control group (n=20). Real-time quantitative polymerase chain reaction (qRT-PCR), immunohistochemistry and Western blot analysis were performed to detect microRNA-200c, Zeb1, TGF-β, and Smad3 mRNA and protein expressions in the model group (n=20) and the control group (n=20). The relationship between microRNA-200c and Zeb1 was detected using a dual-luciferase reporter gene experiment. After the in vitro intervention experiment in fetal rat penises, Western blot was used to detect the expression of Zeb1, TGF-β, and Smad3. RESULTS In the model group, microRNA-200c was expressed at a low level, and microRNA-200c expression in control group was 2.1 times higher than in the model group (Phypospadias occurrence by suppressing the expression of Zeb1, TGF-β, and Smad3. CONCLUSIONS MicroRNA-200c was expressed in hypospadias penis tissues at low levels and was negatively correlated with Zeb1 expression. MicroRNA-200c up-regulated Zeb1 expression to regulate the TGF-β/Smad3 pathway, which led to the occurrence of hypospadias.

  6. Mercury Report-Children's exposure to elemental mercury

    Science.gov (United States)

    ... gov . Mercury Background Mercury Report Additional Resources Mercury Report - Children's Exposure to Elemental Mercury Recommend on Facebook ... I limit exposure to mercury? Why was the report written? Children attending a daycare in New Jersey ...

  7. Interaction of ethanol and mercury body burden in the mouse

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, J.D.

    1978-01-01

    The interaction of ethanol with mercury in the body resulting in increased exhalation of the metal was studied in the mouse. A persistent elimination of the metal in the breath was demonstrated after single, sublethal (<1 mgHg/Kg body weight) exposures to mercury vapor (Hg/sup 0/) or mercury II chloride (HgCl/sub 2/). The amount of mercury exhaled per unit time was enhanced by oral or parenteral administration of ethanol solutions. These modifications were investigated in dose-response studies in which the drug was administered in doses ranging from 0.2g to 5.5g/Kg to mice pretreated with mercury. The EC/sub 50/ for blood ethanol with respect to mercury exhalation was determined to be approximately 200 mg/dl corresponding to an output rate of approximately 0.1% of the simultaneous body burden in 30 min several days after mercury. A hypothesis that mercury expired by these animals was proportional to the body burden after mercury administration was addressed in experiments whereby mice given one of several doses of mercuric chloride (0.16 to 500 ..mu..g/Kg) were monitored for pulmonary mercury elimination for a fifteen day period. The high correlation obtained between the amount of mercury exhaled in a standard time period and the body burden by group indicated that breath sampling could be applied as an indicator of the mercury body burden which may not be limited to the mouse.

  8. Mercury recycling in the United States in 2000

    Science.gov (United States)

    Brooks, William E.; Matos, Grecia R.

    2005-01-01

    Reclamation and recycling of mercury from used mercury- containing products and treatment of byproduct mercury from gold mining is vital to the continued, though declining, use of this metal. Mercury is reclaimed from mercury-containing waste by treatment in multistep high-temperature retorts-the mercury is volatized and then condensed for purification and sale. Some mercury-containing waste, however, may be landfilled, and landfilled material represents loss of a recyclable resource and a threat to the environment. Related issues include mercury disposal and waste management, toxicity and human health, and regulation of mercury releases in the environment. End-users of mercury-containing products may face fines and prosecution if these products are improperly recycled or not recycled. Local and State environmental regulations require adherence to the Resource Conservation and Recovery Act and the Comprehensive Environmental Response, Compensation, and Liability Act to regulate generation, treatment, and disposal of mercury-containing products. In the United States, several large companies and a number of smaller companies collect these products from a variety of sources and then reclaim and recycle the mercury. Because mercury has not been mined as a principal product in the United States since 1992, mercury reclamation from fabricated products has become the main source of mercury. Principal product mercury and byproduct mercury from mining operations are considered to be primary materials. Mercury may also be obtained as a byproduct from domestic or foreign gold-processing operations. In the early 1990s, U.S. manufacturers used an annual average that ranged from 500 to 600 metric tons of recycled and imported mercury for fabrication of automobile convenience switches, dental amalgam, fluorescent lamps, medical uses and thermometers, and thermostats. The amount now used for fabrication is estimated to be 200 metric tons per year or less. Much of the data on

  9. RECOVERY OF MERCURY FROM CONTAMINATED LIQUID WASTES

    Energy Technology Data Exchange (ETDEWEB)

    Robin M. Stewart

    1999-09-29

    Mercury was widely used in U.S. Department of Energy (DOE) weapons facilities, resulting in a broad range of mercury-contaminated wastes and wastewaters. Some of the mercury contamination has escaped to the local environment, particularly at the Y-12 Plant in Oak Ridge, Tennessee, where approximately 330 metric tons of mercury were discharged to the environment between 1953 and 1963 (TN & Associates, 1998). Effective removal of mercury contamination from water is a complex and difficult problem. In particular, mercury treatment of natural waters is difficult because of the low regulatory standards. For example, the Environmental Protection Agency has established a national ambient water quality standard of 12 parts-per-trillion (ppt), whereas the standard is 1.8 ppt in the Great Lakes Region. In addition, mercury in the environment is typically present in several different forms, but sorption processes are rarely effective with more than one or two of these forms. To meet the low regulatory discharge limits, an effective sorption process must be able to address all forms of mercury present in the water. One approach is to apply different sorbents in series depending on the mercury speciation and the regulatory discharge limits. ADA Technologies, Inc. has developed four new sorbents to address the variety of mercury species present in industrial discharges and natural waters. Three of these sorbents have been field tested on contaminated creek water at the Y-12 Plant. Two of these sorbents have been successfully demonstrated very high removal efficiencies for soluble mercury species, reducing mercury concentrations at the outlet of a pilot-scale system to less than 12 ppt for as long as six months. The other sorbent tested at the Y-12 Plant targeted colloidal mercury not removed by standard sorption or filtration processes. At the Y-12 Plant, colloidal mercury appears to be associated with iron, so a sorbent that removes mercury-iron complexes in the presence of a

  10. Mercury Thermal Hydraulic Loop (MTHL) Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Felde, David K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Crye, Jason Michael [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wendel, Mark W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Yoder, Jr, Graydon L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Farquharson, George [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jallouk, Philip A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); McFee, Marshall T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pointer, William David [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ruggles, Art E. [Univ. of Tennessee, Knoxville, TN (United States); Carbajo, Juan J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-03-01

    The Spallation Neutron Source (SNS) is a high-power linear accelerator built at Oak Ridge National Laboratory (ORNL) which incorporates the use of a flowing liquid mercury target. The Mercury Thermal Hydraulic Loop (MTHL) was constructed to investigate and verify the heat transfer characteristics of liquid mercury in a rectangular channel. This report provides a compilation of previously reported results from the water-cooled and electrically heated straight and curved test sections that simulate the geometry of the window cooling channel in the target nose region.

  11. Mercury's Magnetic Field

    Science.gov (United States)

    Johnson, C. L.

    2014-12-01

    Mercury is the only inner solar system body other than Earth to possess an active core dynamo-driven magnetic field and the only planet with a small, highly dynamic magnetosphere. Measurements made by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft have provided a wealth of data on Mercury's magnetic field environment. Mercury's weak magnetic field was discovered 40 years ago by the Mariner 10 spacecraft, but its large-scale geometry, strength and origin could not be definitively established. MESSENGER data have shown that the field is dynamo-generated and can be described as an offset axisymmetric dipole field (hereafter OAD): the magnetic equator lies ~0.2 RM (RM = 2440 km) north of the geographic equator and the dipole moment is 2.8 x1019 Am2 (~0.03% that of Earth's). The weak internal field and the high, but variable, solar wind ram pressure drive vigorous magnetospheric dynamics and result in an average distance from the planet center to the sub-solar magnetopause of only 1.42 RM. Magnetospheric models developed with MESSENGER data have allowed re-analysis of the Mariner 10 observations, establishing that there has been no measureable secular variation in the internal field over 40 years. Together with spatial power spectra for the OAD, this provides critical constraints for viable dynamo models. Time-varying magnetopause fields induce secondary core fields, the magnitudes of which confirm the core radius estimated from MESSENGER gravity and Earth-based radar data. After accounting for large-scale magnetospheric fields, residual signatures are dominated by additional external fields that are organized in the local time frame and that vary with magnetospheric activity. Birkeland currents have been identified, which likely close in the planetary interior at depths below the base of the crust. Near-periapsis magnetic field measurements at altitudes greater than 200 km have tantalizing hints of crustal fields, but crustal

  12. Environmental mercury problem

    Energy Technology Data Exchange (ETDEWEB)

    D' Itri, F.M.

    1972-01-01

    The urgent need to eliminate or greatly reduce the discharge of mercury into the environment is paramount to the health and well being of man. That all forms of mercury are hazardous is widely recognized, but what is more devastating to our society is that all forms of mercury appear to have the potential to be converted in to highly toxic monomethylmercury, or dimethylmercury. This paper examined the historical uses of mercury, the background concentrations of mercury, the analytical methods for the determination of mercury, the contamination of the food chain by mercury, the biological methylation of mercury, the decontamination and restoration of mercury polluted areas, the epidemiology and toxicology of mercury, and the chronology of the world's mercury poisoning problem.

  13. Multi-step processes in the (d, t) and (d, 3He) reactions on 116Sn and 208Pb targets at Ed = 200 MeV

    International Nuclear Information System (INIS)

    Langevin-Joliot, H.; Van de Wiele, J.; Guillot, J.; Koning, A.J.

    2000-01-01

    The role of multi-step processes in the reactions 116 Sn(d,t), 208 Pb(d,t) and 116 Sn(d, 3 He), previously studied at E d = 200 MeV at forward angles and for relatively low energy transfers, has been investigated. We have performed for the first time multi-step calculations taking into account systematically collective excitations in the second and higher order step inelastic transitions. A calculation code based on the Feshbach, Kerman and Koonin model has been modified to handle explicitly these collective excitations, most important in the forward angle domain. One step double differential pick-up cross sections were built from finite range distorted wave results spread in energy using known or estimated hole state characteristics. It is shown that two-step cross sections calculated using the above method compare rather well with those deduced via coupled channel calculations for the same collective excitations. The multi-step calculations performed up to 6 steps reproduce reasonably well the 115 Sn, 207 Pb and 115 In experimental spectra measured up to E x ∼- 40 MeV and 15 deg. The relative contributions of steps of increasing order to pick-up cross sections at E d = 200 MeV and 150 MeV are discussed. (authors)

  14. Mercury Inhibits Soil Enzyme Activity in a Lower Concentration than the Guideline Value.

    Science.gov (United States)

    Mahbub, Khandaker Rayhan; Krishnan, Kannan; Megharaj, Mallavarapu; Naidu, Ravi

    2016-01-01

    Three soil types - neutral, alkaline and acidic were experimentally contaminated with nine different concentrations of inorganic mercury (0, 5, 10, 50, 100, 150, 200, 250, 300 mg/kg) to derive effective concentrations of mercury that exert toxicity on soil quality. Bioavailability of mercury in terms of water solubility was lower in acidic soil with higher organic carbon. Dehydrogenase enzyme activity and nitrification rate were chosen as indicators to assess soil quality. Inorganic mercury significantly inhibited (p mercury contents (EC10) were found to be less than the available safe limits for inorganic mercury which demonstrated inadequacy of existing guideline values.

  15. 33 CFR 334.200 - Chesapeake Bay, Point Lookout to Cedar Point; aerial and surface firing range and target area, U...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Chesapeake Bay, Point Lookout to... Chesapeake Bay, Point Lookout to Cedar Point; aerial and surface firing range and target area, U.S. Naval Air... of Chesapeake Bay within an area described as follows: Beginning at the easternmost extremity of...

  16. Formation of short-lived positron emitters in reactions of protons of energies up to 200 MeV with the target elements carbon, nitrogen and oxygen

    CERN Document Server

    Kettern, K; Qaim, S M; Shubin, Yu N; Steyn, G F; Van der Walt, T N; 10.1016/j.apradiso.2004.02.007

    2004-01-01

    Excitation functions were measured by the stacked-foil technique for proton induced reactions on carbon, nitrogen and oxygen leading to the formation of the short-lived positron emitters /sup 11/C (T/sub 1 /2/=20.38 min) and /sup 13/N (T/sub 1/2/=9.96 min). The energy region covered extended up to 200 MeV. The product activity was measured non-destructively via gamma -ray spectrometry. A careful decay curve analysis of the positron annihilation radiation was invariably performed. The experimental results were compared with theoretical data obtained using the modified hybrid nuclear model code ALICE-IPPE for intermediate energies. The agreement was found to be generally satisfactory. The data are of importance in proton therapy.

  17. Mercury contamination extraction

    Science.gov (United States)

    Fuhrmann, Mark [Silver Spring, MD; Heiser, John [Bayport, NY; Kalb, Paul [Wading River, NY

    2009-09-15

    Mercury is removed from contaminated waste by firstly applying a sulfur reagent to the waste. Mercury in the waste is then permitted to migrate to the reagent and is stabilized in a mercury sulfide compound. The stable compound may then be removed from the waste which itself remains in situ following mercury removal therefrom.

  18. Rethinking mercury: the role of selenium in the pathophysiology of mercury toxicity.

    Science.gov (United States)

    Spiller, Henry A

    2018-05-01

    There is increasing evidence that the pathophysiological target of mercury is in fact selenium, rather than the covalent binding of mercury to sulfur in the body's ubiquitous sulfhydryl groups. The role of selenium in mercury poisoning is multifaceted, bidirectional, and central to understanding the target organ toxicity of mercury. An initial search was performed using Medline/PubMed, Toxline, Google Scholar, and Google for published work on mercury and selenium. These searches yielded 2018 citations. Publications that did not evaluate selenium status or evaluated environmental status (e.g., lake or ocean sediment) were excluded, leaving approximately 500 citations. This initial selection was scrutinized carefully and 117 of the most relevant and representative references were selected for use in this review. Binding of mercury to thiol/sulfhydryl groups: Mercury has a lower affinity for thiol groups and higher affinity for selenium containing groups by several orders of magnitude, allowing for binding in a multifaceted way. The established binding of mercury to thiol moieties appears to primarily involve the transport across membranes, tissue distribution, and enhanced excretion, but does not explain the oxidative stress, calcium dyshomeostasis, or specific organ injury seen with mercury. Effects of mercury on selenium and the role this plays in the pathophysiology of mercury toxicity: Mercury impairs control of intracellular redox homeostasis with subsequent increased intracellular oxidative stress. Recent work has provided convincing evidence that the primary cellular targets are the selenoproteins of the thioredoxin system (thioredoxin reductase 1 and thioredoxin reductase 2) and the glutathione-glutaredoxin system (glutathione peroxidase). Mercury binds to the selenium site on these proteins and permanently inhibits their function, disrupting the intracellular redox environment. A number of other important possible target selenoproteins have been identified

  19. Mercury Quick Facts: Health Effects of Mercury Exposure

    Science.gov (United States)

    Mercury Quick Facts Health Effects of Mercury Exposure What is Elemental Mercury? Elemental (metallic) mercury is the shiny, silver-gray metal found in thermometers, barometers, and thermostats and other ...

  20. Selected case histories and epidemiologic examples of human mercury poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Gerstner, H.B.; Huff, J.E.

    1977-01-01

    Clinical aspects of mercury poisoning are described for elemental mercury, inorganic mercury compounds, and organic mercury compounds. Critical targets of poisoning by elemental mercury are the lungs and the central nervous system. A case of acute pulmonary injury and a case of chronic brain injury are described. The effects of inorganic mercury compounds are chiefly injuries to the alimentary canal and kidneys. Two cases of acute intoxication from these compounds are described. An epidemiologic study on Africans suffering from the nephrotic syndrome showed that aminomercuric chloride was the causative agent. Organic mercury compounds are discussed with regard to the following: individual cases of the methylmercury syndrome in adults; individual cases of prenatal methylmercury intoxication; epidemic outbreaks of methylmercury poisoning; epidemiology of methylmercury poisoning through dressed seed grain; and epidemic outbreaks of poisonings by organomercurials other than methylmercury. (HLW)

  1. Mercury speciation analysis in marine samples by HPLC-ICPMS

    DEFF Research Database (Denmark)

    Rasmussen, Rie Romme; Svendsen, Maja Erecius; Herbst, M. Birgitte Koch

    Mercury (Hg) is a naturally occurring element, which is found in the earth’s crust and can be released into the environment through both natural and anthropogenic processes. Mercury exists as elemental mercury (metallic), inorganic mercury and organic mercury (primarily methylmercury......). Methylmercury is highly toxic, particularly to the nervous system, and the developing brain is thought to be the most sensitive target organ for methylmercury toxicity. Methylmercury bioaccumulates and biomagnifies along the food chain and it is the most common mercury species in fish and seafood. Human...... hydrochloric acid by sonication. Hereby the protein-bound mercury species are released. The extracts were then centrifuged (10 min at 3170 x g) and the supernatant decanted (extraction step was repeated twice). The combined extracts were added 10 M sodium hydroxide to increase pH, following further dilution...

  2. Spectrometric analysis of mercury content in 549 skin-lightening products: is mercury toxicity a hidden global health hazard?

    Science.gov (United States)

    Hamann, Carsten R; Boonchai, Waranya; Wen, Liping; Sakanashi, Emi Nishijima; Chu, Chia-Yu; Hamann, Kylin; Hamann, Curtis P; Sinniah, Kumar; Hamann, Dathan

    2014-02-01

    Cosmetic skin lightening is practiced worldwide. Mercury is a well-documented melanotoxin added to some lightening products. However, mercury can cause many dermatologic, renal, and neurologic problems. The Food and Drug Administration limits the amount of mercury in cosmetic products to trace amounts, 1 ppm. The objective of this study was to quantitatively evaluate a large international sample of lightening products for mercury content, focusing on products available to US consumers either online or in stores. A total of 549 skin-lightening products, manufactured in 32 countries, were purchased online in the United States, Taiwan, and Japan and in stores in the United States, China, Taiwan, Thailand, Japan, and Sri Lanka. Cosmetics were screened for mercury content above 200 ppm using a low-cost portable x-ray fluorescence spectrometer. Of the 549 tested products, 6.0% (n = 33) contained mercury above 1000 ppm. In all, 45% of mercury-containing samples contained mercury in excess of 10,000 ppm. Of lightening products purchased in the United States, 3.3% were found to contain mercury in excess of 1000 ppm. Our study did not evaluate creams for other melanosuppressive ingredients. Only 1 sample of each product was tested. Our study confirms the national and global presence of mercury in skin-lightening products. Copyright © 2013 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

  3. Avian mercury exposure and toxicological risk across western North America: A synthesis

    Science.gov (United States)

    Ackerman, Joshua T.; Eagles-Smith, Collin A.; Herzog, Mark; Hartman, Christopher; Peterson, Sarah; Evers, David C.; Jackson, Allyson K.; Elliott, John E.; Vander Pol, Stacy S.; Bryan, Colleen E.

    2016-01-01

    Methylmercury contamination of the environment is an important issue globally, and birds are useful bioindicators for mercury monitoring programs. The available data on mercury contamination of birds in western North America were synthesized. Original data from multiple databases were obtained and a literature review was conducted to obtain additional mercury concentrations. In total, 29219 original bird mercury concentrations from 225 species were compiled, and an additional 1712 mean mercury concentrations, representing 19998 individuals and 176 species, from 200 publications were obtained. To make mercury data comparable across bird tissues, published equations of tissue mercury correlations were used to convert all mercury concentrations into blood-equivalent mercury concentrations. Blood-equivalent mercury concentrations differed among species, foraging guilds, habitat types, locations, and ecoregions. Piscivores and carnivores exhibited the greatest mercury concentrations, whereas herbivores and granivores exhibited the lowest mercury concentrations. Bird mercury concentrations were greatest in ocean and salt marsh habitats and lowest in terrestrial habitats. Bird mercury concentrations were above toxicity benchmarks in many areas throughout western North America, and multiple hotspots were identified. Additionally, published toxicity benchmarks established in multiple tissues were summarized and translated into a common blood-equivalent mercury concentration. Overall, 66% of birds sampled in western North American exceeded a blood-equivalent mercury concentration of 0.2 μg/g wet weight (ww; above background levels), which is the lowest-observed effect level, 28% exceeded 1.0 μg/g ww (moderate risk), 8% exceeded 3.0 μg/g ww (high risk), and 4% exceeded 4.0 μg/g ww (severe risk). Mercury monitoring programs should sample bird tissues, such as adult blood and eggs, that are most-easily translated into tissues with well-developed toxicity benchmarks and that

  4. Minamata Convention on Mercury

    Science.gov (United States)

    On November 6, 2013 the United States signed the Minamata Convention on Mercury, a new multilateral environmental agreement that addresses specific human activities which are contributing to widespread mercury pollution

  5. The 1:3M geologic map of Mercury: progress and updates

    Science.gov (United States)

    Galluzzi, Valentina; Guzzetta, Laura; Mancinelli, Paolo; Giacomini, Lorenza; Malliband, Christopher C.; Mosca, Alessandro; Wright, Jack; Ferranti, Luigi; Massironi, Matteo; Pauselli, Cristina; Rothery, David A.; Palumbo, Pasquale

    2017-04-01

    After the end of Mariner 10 mission a 1:5M geologic map of seven of the fifteen quadrangles of Mercury [Spudis and Guest, 1988] was produced. The NASA MESSENGER mission filled the gap by imaging 100% of the planet with a global average resolution of 200 m/pixel and this led to the production of a global 1:15M geologic map of the planet [Prockter et al., 2016]. Despite the quality gap between Mariner 10 and MESSENGER images, no global geological mapping project with a scale larger than 1:5M has been proposed so far. Here we present the status of an ongoing project for the geologic mapping of Mercury at an average output scale of 1:3M based on the available MESSENGER data. This project will lead to a fuller grasp of the planet's stratigraphy and surface history. Completing such a product for Mercury is an important goal in preparation for the forthcoming ESA/JAXA BepiColombo mission to aid selection of scientific targets and to provide context for interpretation of new data. At the time of this writing, H02 Victoria [Galluzzi et al., 2016], H03 Shakespeare [Guzzetta et al., 2016] and H04 Raditladi [Mancinelli et al., 2016] have been completed and H05 Hokusai [Rothery et al., 2017], H06 Kuiper [Giacomini et al., 2017], H07 Beethoven and H10 Derain [Malliband et al., 2017] are being mapped. The produced geologic maps were merged using the ESRI ArcGIS software adjusting discontinuous contacts along the quadrangle boundaries. Contact discrepancies were reviewed and discussed among the mappers of adjoining quadrangles in order to match the geological interpretation and provide a unique consistent stratigraphy. At the current stage, more than 20% of Mercury has now a complete 1:3M map and more than 40% of the planet will be covered soon by the maps that are being prepared. This research was supported by the Italian Space Agency (ASI) within the SIMBIOSYS project (ASI-INAF agreement no. I/022/10/0). References Galluzzi V. et al. (2016). Geology of the Victoria Quadrangle (H

  6. Mercury in Your Environment

    Science.gov (United States)

    Basic information about mercury, how it gets in the air, how people are exposed to it and health effects associated with exposure; what EPA and other organizations are doing to limit exposures; what citizens should know to minimize exposures and to reduce mercury in the environment; and information about products that contain mercury.

  7. Intentional intravenous mercury injection

    African Journals Online (AJOL)

    Three forms of mercury exist: elemental, inorganic and organic, all of which may be toxic with clinical consequences, depending on the type of exposure. Elemental mercury poisoning usually occurs via vapour inhalation, as mercury is well absorbed through the lungs. The central nervous system is then the major site of ...

  8. Analysis of dependence of fission cross section and angular anisotropy of the 235U fission fragment escape induced by neutrons of intermediate energies (epsilon < or approximately200 keV) on target nucleus orientation

    International Nuclear Information System (INIS)

    Barabanov, A.L.

    1985-01-01

    Experimental data on dependence of fission cross section Σsub(f) (epsilon) and angular anisotropy W(epsilon, 0 deg)/W(epsilon, 90 deg) of sup(235)U fission fragment escape by neutrons with energy epsilon=100 and 200 keV on orientation of target nuclei are analyzed. 235 U (Isup(πsub(0))=7/2sup(-)) nuclei were orientated at the expense of interaction of quadrupole nucleus momenta with nonuniform electric field of uranyl-rubidium nitrate crystal at crystal cooling to T=0.2 K. The analysis was carried out with three different sets of permeability factors T(epsilon). Results of the analysis weakly depend on T(epsilon) choice. It is shown that a large number of adjusting parameters (six fissionabilities γsup(f)(Jsup(π), epsilon) and six momenta sub(Jsup(π))) permit to described experimental data on Σsub(f)(epsilon) and W(epsilon, 0 deg)/W(epsilon, 90 deg), obtained at epsilon=200 keV by introducing essential dependence of γsup(f)(Jsup(π), epsilon) and sub(Jsup(π)) on Jsup(π). Estimations of fission cross sections Σsub(f)(epsilon) and angular distribution W(epsilon, n vector) up to T approximately equal to 0.01 K in two geometries of the experiment: the orientation axis is parallel and perpendicular to momentum direction p vector of incident neutrons, are conducted

  9. The experiment of the elemental mercury was removed from natural gas by 4A molecular sieve

    Science.gov (United States)

    Jiang, Cong; Chen, Yanhao

    2018-04-01

    Most of the world's natural gas fields contain elemental mercury and mercury compounds, and the amount of mercury in natural gas is generally 1μg/m3 200μg/m3. This paper analyzes the mercury removal principle of chemical adsorption process, the characteristics and application of mercury removal gent and the factors that affect the efficiency of mercury removal. The mercury in the natural gas is adsorbed by the mercury-silver reaction of the 4 molecular sieve after the manned treatment. The limits for mercury content for natural gas for different uses and different treatment processes are also different. From the environmental protection, safety and other factors, it is recommended that the mercury content of natural gas in the pipeline is less than 28μg / m3, and the mercury content of the raw material gas in the equipment such as natural gas liquefaction and natural gas condensate recovery is less than 0.01μg/m3. This paper mainly analyzes the existence of mercury in natural gas, and the experimental research process of using 4A molecular sieve to absorb mercury in natural gas.

  10. FOXD1 is targeted by miR-30a-5p and miR-200a-5p and suppresses the proliferation of human ovarian carcinoma cells by promoting p21 expression in a p53-independent manner.

    Science.gov (United States)

    Wang, Yu; Qiu, Chunping; Lu, Nan; Liu, Zhaojian; Jin, Chengjuan; Sun, Chenggong; Bu, Hualei; Yu, Hongfeng; Dongol, Samina; Kong, Beihua

    2018-04-04

    High-grade serous ovarian carcinoma (HGSOC) accounts for the highest number of deaths among patients with epithelial ovarian cancer. However, the molecular mechanisms underlying HGSOC tumorigenesis are currently unclear. In the present study, a lentiviral expression system was employed to manipulate forkhead box D1 (FOXD1) expression in ovarian cancer cells. Immunohistochemical staining was used to examine the expression of FOXD1 in tissue samples. Clonogenic and MTT assays were employed to evaluate cell proliferation, and flow cytometry was applied for cell cycle analysis. Dual-luciferase reporter and chromatin immunoprecipitation assays were used to determine the role of FOXD1 in regulating p21 expression. The results demonstrated that FOXD1 expression was downregulated in HGSOC, and high expression levels of FOXD1 were found to be a predictor of good prognosis. FOXD1 significantly inhibited the proliferation of human ovarian cancer cells and induced cell cycle arrest at G1 phase in vitro. In addition, exogenous FOXD1 expression inhibited ovarian cancer cell growth in vivo. Furthermore, microRNA (miR)-30a-5p and miR-200a-5p were observed to be upregulated in HGSOC, and function as direct negative regulators of FOXD1 by targeting its 3'-untranslated region. The present study also revealed that FOXD1 promotes p21 expression in a p53-independent manner. In conclusion, the results of the present study indicate a direct association between FOXD1 and p21 that may be mediated by miR-30a-5p and miR-200a-5p. The authors hypothesize that FOXD1 may serve as a biomarker or therapeutic target in HGSOC.

  11. Axial mercury segregation in direct current operated low-pressure argon-mercury gas discharges: Part I. Experimental

    International Nuclear Information System (INIS)

    Gielen, John W A M; Groot, Simon de; Mullen, Joost J A M van der

    2004-01-01

    Due to cataphoresis, axial segregation of mercury will occur when the gas discharge of a fluorescent lamp is operated by means of a direct current. A consequence of this is a non-uniform axial luminance distribution along the lamp. To determine the degree of axial mercury segregation experimentally, axial luminance distributions have been measured which are converted into axial mercury vapour pressure distributions by an appropriate calibration method. The mercury segregation has been investigated for variations in lamp tube radius (3.6-4.8 mm), argon buffer gas pressure (200-600 Pa) and lamp current (100-250 mA) at mercury vapour pressures set at the anode in the range from 0.2 to 9.0 Pa. From the experiments it has been concluded that the mercury vapour pressure gradient at any axial position for a certain lamp tube diameter, argon pressure and lamp current depends on the local mercury vapour pressure. This observation is in contrast to assumptions made in earlier modelling publications in which one mercury vapour pressure gradient is used for all axial positions. By applying a full factorial design, an empirical relation of the mercury segregation is found for any set of parameters inside the investigated parameter ranges

  12. Mercury evaporation from amalgams with varied mercury contents.

    Science.gov (United States)

    Ohmoto, K; Nakajima, H; Ferracane, J L; Shintani, H; Okabe, T

    2000-09-01

    This study examined the relationship between mercury content and mercury evaporation from amalgams during setting. Two different types of commercial high-copper amalgams (single composition and admixed types) were used. Cylindrical specimens of each amalgam were prepared with five different mercury contents according to ADA Specification No.1. Specimens were also prepared by hand condensation. Mercury evaporation from amalgam specimens maintained at 37 degrees C was measured using a gold film mercury analyzer from 10 min after the end of trituration until the mercury concentration in air reached an undetectable level. The mercury content more clearly influenced the mercury evaporation from the admixed type amalgam specimens when the mercury content decreased below the manufacturers' recommended trituration conditions. Triturating with less mercury than the manufacturers' recommended amount cannot lower the evaporation of mercury from freshly made amalgam. Proper condensing procedures can minimize the mercury evaporation from the amalgam surface.

  13. A gradient of mercury concentrations in Scottish single malt whiskies.

    Science.gov (United States)

    Rose, Neil L; Yang, Handong; Turner, Simon D

    2016-02-01

    Mercury (Hg) concentrations were measured in 26 Scottish single malt whiskies, and all found to be very low (mercury emissions and deposition over the last 200 years affecting concentrations in local waters used in whisky production. As UK atmospheric emissions of mercury have declined by 90 % since the 1970s, we suggest that whisky being produced today should have even lower Hg concentrations when consumed in 10- to 15-years time. This reduction may be compromised by the remobilisation of contaminants stored in catchment soils being transferred to source waters, but is very unlikely to raise the negligible health risk due to Hg from Scottish single malt whisky consumption.

  14. Process for low mercury coal

    Science.gov (United States)

    Merriam, Norman W.; Grimes, R. William; Tweed, Robert E.

    1995-01-01

    A process for producing low mercury coal during precombustion procedures by releasing mercury through discriminating mild heating that minimizes other burdensome constituents. Said mercury is recovered from the overhead gases by selective removal.

  15. Epithelial-mesenchymal transition, a novel target of sulforaphane via COX-2/MMP2, 9/Snail, ZEB1 and miR-200c/ZEB1 pathways in human bladder cancer cells.

    Science.gov (United States)

    Shan, Yujuan; Zhang, Lanwei; Bao, Yongping; Li, Baolong; He, Canxia; Gao, Mingming; Feng, Xue; Xu, Weili; Zhang, Xiaohong; Wang, Shuran

    2013-06-01

    Metastasis and recurrence of bladder cancer are the main reasons for its poor prognosis and high mortality rates. Because of its biological activity and high metabolic accumulation in urine, sulforaphane, a phytochemical exclusively occurring in cruciferous vegetables, has a powerful and specific potential for preventing bladder cancer. In this paper, sulforaphane is shown to significantly suppress a variety of biochemical pathways including the attachment, invasion, migration and chemotaxis motion in malignant transitional bladder cancer T24 cells. Transfection with cyclooxygenase-2 (COX-2) overexpression plasmid largely abolished inhibition of MMP2/9 expression as well as cell invasive capability by sulforaphane. Moreover, sulforaphane inhibited the epithelial-to-mesenchymal transition (EMT) process which underlies tumor cell invasion and migration mediated by E-cadherin induction through reducing transcriptional repressors, such as ZEB1 and Snail. Under conditions of over-expression of COX-2 and/or MMP2/9, sulforaphane was still able to induce E-cadherin or reduce Snail/ZEB1 expression, suggesting that additional pathways might be involved. Further studies indicated that miR-200c played a role in the regulation of E-cadherin via the ZEB1 repressor but not by the Snail repressor. In conclusion, the EMT and two recognized signaling pathways (COX-2/MMP2,9/ ZEB1, Snail and miR-200c/ZEB1) are all targets for sulforaphane. This study indicated that sulforaphane may possess therapeutic potential in preventing recurrence of human bladder cancer. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Mercury is Moon's brother

    International Nuclear Information System (INIS)

    Ksanfomalifi, L.V.

    1976-01-01

    The latest information on Mercury planet is presented obtained by studying the planet with the aid of radar and space vehicles. Rotation of Mercury about its axis has been discovered; within 2/3 of its year it executes a complete revolution about its axis. In images obtained by the ''Mariner-10'' Mercurys surface differs little from that of the Moon. The ''Mariner-10'' has also discovered the Mercurys atmosphere, which consists of extremely rarefied helium. The helium is continuously supplied to the planet by the solar wind. The Mercury's magnetic field has been discovered, whose strength is 35 x 10 -4 at the Equator and 70 x 10 -4 E at the poles. The inclination of the dipole axis to the Mercury's rotation axis is 7 deg

  17. Peru Mercury Inventory 2006

    Science.gov (United States)

    Brooks, William E.; Sandoval, Esteban; Yepez, Miguel A.; Howard, Howell

    2007-01-01

    In 2004, a specific need for data on mercury use in South America was indicated by the United Nations Environmental Programme-Chemicals (UNEP-Chemicals) at a workshop on regional mercury pollution that took place in Buenos Aires, Argentina. Mercury has long been mined and used in South America for artisanal gold mining and imported for chlor-alkali production, dental amalgam, and other uses. The U.S. Geological Survey (USGS) provides information on domestic and international mercury production, trade, prices, sources, and recycling in its annual Minerals Yearbook mercury chapter. Therefore, in response to UNEP-Chemicals, the USGS, in collaboration with the Economic Section of the U.S. Embassy, Lima, has herein compiled data on Peru's exports, imports, and byproduct production of mercury. Peru was selected for this inventory because it has a 2000-year history of mercury production and use, and continues today as an important source of mercury for the global market, as a byproduct from its gold mines. Peru is a regional distributor of imported mercury and user of mercury for artisanal gold mining and chlor-alkali production. Peruvian customs data showed that 22 metric tons (t) of byproduct mercury was exported to the United States in 2006. Transshipped mercury was exported to Brazil (1 t), Colombia (1 t), and Guyana (1 t). Mercury was imported from the United States (54 t), Spain (19 t), and Kyrgyzstan (8 t) in 2006 and was used for artisanal gold mining, chlor-alkali production, dental amalgam, or transshipment to other countries in the region. Site visits and interviews provided information on the use and disposition of mercury for artisanal gold mining and other uses. Peru also imports mercury-containing batteries, electronics and computers, fluorescent lamps, and thermometers. In 2006, Peru imported approximately 1,900 t of a wide variety of fluorescent lamps; however, the mercury contained in these lamps, a minimum of approximately 76 kilograms (kg), and in

  18. RECOVERY OF MERCURY FROM CONTAMINATED PRIMARY AND SECONDARY WASTES

    International Nuclear Information System (INIS)

    A. Faucette; J. Bognar; T. Broderick; T. Battaglia

    2000-01-01

    Effective removal of mercury contamination from water is a complex and difficult problem. In particular, mercury treatment of natural waters is difficult because of the low regulatory standards. For example, the Environmental Protection Agency has established a national ambient water quality standard of 12 parts-per-trillion (ppt), whereas the standard is 1.8 ppt in the Great Lakes Region. In addition, mercury is typically present in several different forms, but sorption processes are rarely effective with more than one or two of these forms. To meet the low regulatory discharge limits, a sorption process must be able to address all forms of mercury present in the water. One approach is to apply different sorbents in series depending on the mercury speciation and the regulatory discharge limits. Four new sorbents have been developed to address the variety of mercury species present in industrial discharges and natural waters. Three of these sorbents have been field tested on contaminated creek water at the Y-12 Plant. Two of these sorbents have demonstrated very high removal efficiencies for soluble mercury species, with mercury concentrations at the outlet of a pilot-scale system less than 12 ppt for as long as six months. The other sorbent tested at the Y-12 Plant is targeted at colloidal mercury that is not removed by standard sorption or filtration processes. At the Y-12 Plant, colloidal mercury appears to be associated with iron, so a sorbent that removes mercury-iron complexes in the presence of a magnetic field was evaluated. Field results indicate good removal of this mercury fraction from the Y-12 waters. In addition, this sorbent is easily regenerated by simply removing the magnetic field and flushing the columns with water. The fourth sorbent is still undergoing laboratory development, but results to date indicate exceptionally high mercury sorption capacity. The sorbent is capable of removing all forms of mercury typically present in natural and

  19. Conductometric Sensors for Detection of Elemental Mercury Vapor

    Science.gov (United States)

    Ryan, M. A.; Homer, M. L.; Shevade, A. V.; Lara, L. M.; Yen, S.-P. S.; Kisor, A. K.; Manatt, K. S.

    2008-01-01

    Several organic and inorganic materials have been tested for possible incorporation into a sensing array in order to add elemental mercury vapor to the suite of chemical species detected. Materials have included gold films, treated gold films, polymer-carbon composite films, gold-polymer-carbon composite films and palladium chloride sintered films. The toxicity of mercury and its adverse effect on human and animal health has made environmental monitoring of mercury in gas and liquid phases important (1,2). As consumer products which contain elemental mercury, such as fluorescent lighting, become more widespread, the need to monitor environments for the presence of vapor phase elemental mercury will increase. Sensors in use today to detect mercury in gaseous streams are generally based on amalgam formation with gold or other metals, including noble metals and aluminum. Recently, NASA has recognized a need to detect elemental mercury vapor in the breathing atmosphere of the crew cabin in spacecraft and has requested that such a capability be incorporated into the JPL Electronic Nose (3). The detection concentration target for this application is 10 parts-per-billion (ppb), or 0.08 mg/m3. In order to respond to the request to incorporate mercury sensing into the JPL Electronic Nose (ENose) platform, it was necessary to consider only conductometric methods of sensing, as any other transduction method would have required redesign of the platform. Any mercury detection technique which could not be incorporated into the existing platform, such as an electrochemical technique, could not be considered.

  20. MESSENGER at Mercury: Early Orbital Operations

    Science.gov (United States)

    McNutt, Ralph L., Jr; Solomon, Sean C.; Bedini, Peter D.; Anderson, Brian J.; Blewett, David T.; Evans, Larry G.; Gold, Robert E.; Krimigis, Stamatios M.; Murchie, Scott L.; Nittler, Larry R.; hide

    2013-01-01

    The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched in August 2004 under NASA's Discovery Program, was inserted into orbit about the planet Mercury in March 2011. MESSENGER's three flybys of Mercury in 2008-2009 marked the first spacecraft visits to the innermost planet since the Mariner 10 flybys in 1974-1975. The unprecedented orbital operations are yielding new insights into the nature and evolution of Mercury. The scientific questions that frame the MESSENGER mission led to the mission measurement objectives to be achieved by the seven payload instruments and the radio science experiment. Interweaving the full set of required orbital observations in a manner that maximizes the opportunity to satisfy all mission objectives and yet meet stringent spacecraft pointing and thermal constraints was a complex optimization problem that was solved with a software tool that simulates science observations and tracks progress toward meeting each objective. The final orbital observation plan, the outcome of that optimization process, meets all mission objectives. MESSENGER's Mercury Dual Imaging System is acquiring a global monochromatic image mosaic at better than 90% coverage and at least 250 m average resolution, a global color image mosaic at better than 90% coverage and at least 1 km average resolution, and global stereo imaging at better than 80% coverage and at least 250 m average resolution. Higher-resolution images are also being acquired of targeted areas. The elemental remote sensing instruments, including the Gamma-Ray and Neutron Spectrometer and the X-Ray Spectrometer, are being operated nearly continuously and will establish the average surface abundances of most major elements. The Visible and Infrared Spectrograph channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer is acquiring a global map of spectral reflectance from 300 to 1450 nm wavelength at a range of incidence and emission

  1. Modeling Mercury in Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Jeremy C [ORNL; Parks, Jerry M [ORNL

    2016-01-01

    Mercury (Hg) is a naturally occurring element that is released into the biosphere both by natural processes and anthropogenic activities. Although its reduced, elemental form Hg(0) is relatively non-toxic, other forms such as Hg2+ and, in particular, its methylated form, methylmercury, are toxic, with deleterious effects on both ecosystems and humans. Microorganisms play important roles in the transformation of mercury in the environment. Inorganic Hg2+ can be methylated by certain bacteria and archaea to form methylmercury. Conversely, bacteria also demethylate methylmercury and reduce Hg2+ to relatively inert Hg(0). Transformations and toxicity occur as a result of mercury interacting with various proteins. Clearly, then, understanding the toxic effects of mercury and its cycling in the environment requires characterization of these interactions. Computational approaches are ideally suited to studies of mercury in proteins because they can provide a detailed picture and circumvent issues associated with toxicity. Here we describe computational methods for investigating and characterizing how mercury binds to proteins, how inter- and intra-protein transfer of mercury is orchestrated in biological systems, and how chemical reactions in proteins transform the metal. We describe quantum chemical analyses of aqueous Hg(II), which reveal critical factors that determine ligand binding propensities. We then provide a perspective on how we used chemical reasoning to discover how microorganisms methylate mercury. We also highlight our combined computational and experimental studies of the proteins and enzymes of the mer operon, a suite of genes that confers mercury resistance in many bacteria. Lastly, we place work on mercury in proteins in the context of what is needed for a comprehensive multi-scale model of environmental mercury cycling.

  2. Isotopic Fractionation of Mercury in Great Lakes Precipitation

    Science.gov (United States)

    Gratz, L. E.; Keeler, G. J.; Blum, J. D.; Sherman, L. S.

    2009-12-01

    Mercury (Hg) is a hazardous bioaccumulative neurotoxin, and atmospheric deposition is a primary way in which mercury enters terrestrial and aquatic ecosystems. However, the chemical processes and transport regimes that mercury undergoes from emission to deposition are not well understood. Thus the use of mercury isotopes to characterize the biogeochemical cycling of mercury is a rapidly growing area of study. Precipitation samples were collected in Chicago, IL, Holland, MI, and Dexter, MI from April 2007 - October 2007 to begin examining the isotopic fractionation of atmospheric mercury in the Great Lakes region. Results show that mass-dependent fractionation relative to NIST-3133 (MDF - δ202Hg) ranged from -0.8‰ to 0.2‰ (±0.2‰) in precipitation samples, while mass-independent fractionation (MIF - Δ199Hg) varied from 0.1‰ to 0.6‰ (±0.1‰). Although clear urban-rural differences were not observed, this may be due to the weekly collection of precipitation samples rather than collection of individual events, making it difficult to truly characterize the meteorology and source influences associated with each sample and suggesting that event-based collection is necessary during future sampling campaigns. Additionally, total vapor phase mercury samples were collected in Dexter, MI in 2009 to examine isotopic fractionation of mercury in ambient air. In ambient samples δ202Hg ranged from 0.3‰ to 0.5‰ (±0.1‰), however Δ199Hg was not significant. Because mercury in precipitation is predominantly Hg2+, while ambient vapor phase mercury is primarily Hg0, these results may suggest the occurrence of MIF during the oxidation of Hg0 to Hg2+ prior to deposition. Furthermore, although it has not been previously reported or predicted, MIF of 200Hg was also detected. Δ200Hg ranged from 0.0‰ to 0.2‰ in precipitation and from -0.1‰ to 0.0‰ in ambient samples. This work resulted in methodological developments in the collection and processing of

  3. Intentional intravenous mercury injection

    African Journals Online (AJOL)

    In this case report, intravenous complications, treatment strategies and possible ... Mercury toxicity is commonly associated with vapour inhalation or oral ingestion, for which there exist definite treatment options. Intravenous mercury ... personality, anxiousness, irritability, insomnia, depression and drowsi- ness.[1] However ...

  4. International mercury conference

    CSIR Research Space (South Africa)

    Leaner, J

    2006-10-01

    Full Text Available Mercury (Hg) affects human health and the environment, it calls for immediate action. Action is needed at local, regional and international level to reduce the risk associated with mercury, which is a global international problem, as it is a...

  5. Mercury's shifting, rolling past

    OpenAIRE

    Trulove, Susan

    2008-01-01

    Patterns of scalloped-edged cliffs or lobate scarps on Mercury's surface are thrust faults that are consistent with the planet shrinking and cooling with time. However, compression occurred in the planet's early history and Mariner 10 images revealed decades ago that lobate scarps are among the youngest features on Mercury. Why don't we find more evidence of older compressive features?

  6. MESSENGER: Exploring Mercury's Magnetosphere

    Science.gov (United States)

    Slavin, James A.

    2008-01-01

    The MESSENGER mission to Mercury offers our first opportunity to explore this planet's miniature magnetosphere since Mariner 10's brief fly-bys in 1974-5. Mercury's magnetosphere is unique in many respects. The magnetosphere of Mercury is the smallest in the solar system with its magnetic field typically standing off the solar wind only - 1000 to 2000 km above the surface. For this reason there are no closed dri-fi paths for energetic particles and, hence, no radiation belts; the characteristic time scales for wave propagation and convective transport are short possibly coupling kinetic and fluid modes; magnetic reconnection at the dayside magnetopause may erode the subsolar magnetosphere allowing solar wind ions to directly impact the dayside regolith; inductive currents in Mercury's interior should act to modify the solar In addition, Mercury's magnetosphere is the only one with its defining magnetic flux tubes rooted in a planetary regolith as opposed to an atmosphere with a conductive ionosphere. This lack of an ionosphere is thought to be the underlying reason for the brevity of the very intense, but short lived, approx. 1-2 min, substorm-like energetic particle events observed by Mariner 10 in Mercury's magnetic tail. In this seminar, we review what we think we know about Mercury's magnetosphere and describe the MESSENGER science team's strategy for obtaining answers to the outstanding science questions surrounding the interaction of the solar wind with Mercury and its small, but dynamic magnetosphere.

  7. Global Mercury Assessment 2013

    International Development Research Centre (IDRC) Digital Library (Canada)

    mercury pollution. This summary report and the accompanying. Technical Background Report for the Global. Mercury Assessment 2013 are developed in response to Decision 25/5, paragraph ... The use of different pollution control technologies in different ...... vegetation, snow, freshwater, and seawater. One of the largest ...

  8. Mercury in canned tuna: white versus light and temporal variation

    International Nuclear Information System (INIS)

    Burger, Joanna; Gochfeld, Michael

    2004-01-01

    mercury. These data indicate that people who eat canned tuna frequently can choose light tuna and reduce their mercury intake. Canned mackerel had much lower levels of mercury than tuna. Since cans of white tuna frequently exceed the FDA's original action level of 0.5 ppm, it would be prudent to continue some systematic monitoring of the nation's canned fish supply, particularly as the targets of commercial fisheries inevitably change as certain stocks become depleted

  9. Municipal actions to reduce mercury

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-03-15

    This paper presented proper management practices for products containing mercury. The measures can help reduce mercury releases, occupational exposure and mercury spills, thereby preventing impacts on human health and the environment. Despite mercury's toxic nature, many common products that contain mercury are commercially available. These include thermostats, thermometers, fluorescent lamps, pressure measuring devices, electrical switches and relays, and dental amalgam. Mercury emissions are also associated with base metal smelting, waste incineration and coal-fired power generation. Mercury in the environment is a global issue, because it can travel in the atmosphere on wind currents. The actions taken by municipalities to address the issue include reducing or eliminating mercury releases from internal municipal operations and sources within the community. This document provided guidance on how to develop a Municipal Mercury Elimination Policy and Plan that will help reduce mercury releases. It presented information and case studies that will help municipalities manage mercury-containing products found in municipal buildings and street lighting. Information on sources of mercury from within the community was presented along with case studies that can help municipalities determine where community action is needed to reduce mercury releases. The 5 modules of this document were intended to help municipalities identify priorities, timelines and budget requirements for mercury initiatives. It was emphasized that municipalities that adopt a Municipal Mercury Elimination Policy and Plan formally commit to reducing and eliminating mercury from the environment. tabs., figs.

  10. Getting Mercury out of Schools.

    Science.gov (United States)

    1999

    This guide was prepared while working with many Massachusetts schools to remove items that contain mercury and to find suitable alternatives. It contains fact sheets on: mercury in science laboratories and classrooms, mercury in school buildings and maintenance areas, mercury in the medical office and in medical technology classrooms in vocational…

  11. Rijksmuseum 200aastane

    Index Scriptorium Estoniae

    2000-01-01

    Amsterdami Rijksmuseum (Riigimuuseum ئ suurimaid madalmaade, flaami ja hollandi kunsti kollektsioone) tähistab avamise 200. aastapäeva 25. juunini avatud ajaloolise ekspositsiooniga 'Kuninglik muuseum. Louis Napoleon ja Rijksmuseum' muuseumi kujunemisperioodist.

  12. Effects of wettability on forced convective and gas-liquid two-phase flow heat transfer of mercury

    International Nuclear Information System (INIS)

    Nakagawa, Yusuke; Kawakita, Keisuke; Takenaka, Nobuyuki

    2003-01-01

    High-energy proton beam is irradiated to a target made of high atomic number materials to initiate nuclear spallation reaction to obtain neutron source. A mercury target is now a candidate of the target for the intense proton beam. It is important to study thermal hydraulics of the mercury target. In this study, mercury was used as a working fluid in a stainless steel tube heated by direct electrical current in similar thermal hydraulic situation to the actual target. The effects of mercury wettability on forced convective heat transfer and gas-liquid two-phase flow heat transfer were verified. (author)

  13. Effect of zinc, cadmium and mercury salts on the growth of Lactic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Savel, J.; Prokopova, M.

    1974-01-01

    This paper discusses the effects of zinc, cadmium, and mercury salts on the growth of lactic bacteria. The organisms used in the study were Pediococcus and Lactobacillus. Both organisms were equally sensitive to mercury. The minimum inhibitory concentrations of Cadmium chloride were 200-1400 mg/l for the Lactobacillus and 1.6-200 mg/l for Pediococcus. The inhibitory effects of zinc salts were similar but occurred at much higher concentrations. 5 tables.

  14. Association between Blood Mercury Level and Visceral Adiposity in Adults

    Directory of Open Access Journals (Sweden)

    Jong Suk Park

    2017-01-01

    Full Text Available BackgroundFew studies have examined the association between mercury exposure and obesity. The aim of this study is to investigate the association between blood mercury concentrations and indices of obesity in adults.MethodsA total of 200 healthy subjects, aged 30 to 64 years, who had no history of cardiovascular or malignant disease, were examined. Anthropometric and various biochemical profiles were measured. Visceral adipose tissue (VAT was measured using dual-energy X-ray absorptiometry (DXA.ResultsAll subjects were divided into three groups according to blood mercury concentrations. Compared with the subjects in the lowest tertile of mercury, those in the highest tertile were more likely to be male; were current alcohol drinkers and smokers; had a higher body mass index (BMI, waist circumference (WC, and VAT; had higher levels of blood pressure, fasting glucose, and insulin resistance; and consumed more fish. The blood mercury concentration was significantly associated with anthropometric parameters, showing relationships with BMI, WC, and VAT. After adjusting for multiple risk factors, the odds ratios (ORs for high mercury concentration was significantly higher in the highest VAT tertile than in the lowest VAT tertile (OR, 2.66; 95% confidence interval, 1.05 to 6.62; P<0.05.ConclusionThe blood mercury concentration was significantly associated with VAT in healthy adults. Further studies are warranted to confirm our findings.

  15. Mercury's Dynamic Magnetic Tail

    Science.gov (United States)

    Slavin, James A.

    2010-01-01

    The Mariner 10 and MESSENGER flybys of Mercury have revealed a magnetosphere that is likely the most responsive to upstream interplanetary conditions of any in the solar system. The source of the great dynamic variability observed during these brief passages is due to Mercury's proximity to the Sun and the inverse proportionality between reconnection rate and solar wind Alfven Mach number. However, this planet's lack of an ionosphere and its small physical dimensions also contribute to Mercury's very brief Dungey cycle, approx. 2 min, which governs the time scale for internal plasma circulation. Current observations and understanding of the structure and dynamics of Mercury's magnetotail are summarized and discussed. Special emphasis will be placed upon such questions as: 1) How much access does the solar wind have to this small magnetosphere as a function of upstream conditions? 2) What roles do heavy planetary ions play? 3) Do Earth-like substorms take place at Mercury? 4) How does Mercury's tail respond to extreme solar wind events such coronal mass ejections? Prospects for progress due to advances in the global magnetohydrodynamic and hybrid simulation modeling and the measurements to be taken by MESSENGER after it enters Mercury orbit on March 18, 2011 will be discussed.

  16. Inorganic: the other mercury.

    Science.gov (United States)

    Risher, John F; De Rosa, Christopher T

    2007-11-01

    There is a broad array of mercury species to which humans may be exposed. While exposure to methylmercury through fish consumption is widely recognized, the public is less aware of the sources and potential toxicity of inorganic forms of mercury. Some oral and laboratory thermometers, barometers, small batteries, thermostats, gas pressure regulators, light switches, dental amalgam fillings, cosmetic products, medications, cultural/religious practices, and gold mining all represent potential sources of exposure to inorganic forms of mercury. The route of exposure, the extent of absorption, the pharmacokinetics, and the effects all vary with the specific form of mercury and the magnitude and duration of exposure. If exposure is suspected, a number of tissue analyses can be conducted to confirm exposure or to determine whether an exposure might reasonably be expected to be biologically significant. By contrast with determination of exposure to methylmercury, for which hair and blood are credible indicators, urine is the preferred biological medium for the determination of exposure to inorganic mercury, including elemental mercury, with blood normally being of value only if exposure is ongoing. Although treatments are available to help rid the body of mercury in cases of extreme exposure, prevention of exposure will make such treatments unnecessary. Knowing the sources of mercury and avoiding unnecessary exposure are the prudent ways of preventing mercury intoxication. When exposure occurs, it should be kept in mind that not all unwanted exposures will result in adverse health consequences. In all cases, elimination of the source of exposure should be the first priority of public health officials.

  17. Geodesy at Mercury with MESSENGER

    Science.gov (United States)

    Smith, David E.; Zuber, Maria t.; Peale, Stanley J.; Phillips, Roger J.; Solomon, Sean C.

    2006-01-01

    In 2011 the MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) spacecraft will enter Mercury orbit and begin the mapping phase of the mission. As part of its science objectives the MESSENGER mission will determine the shape and gravity field of Mercury. These observations will enable the topography and the crustal thickness to be derived for the planet and will determine the small libration of the planet about its axis, the latter critical to constraining the state of the core. These measurements require very precise positioning of the MESSENGER spacecraft in its eccentric orbit, which has a periapsis altitude as low as 200 km, an apoapsis altitude near 15,000 km, and a closest approach to the surface varying from latitude 60 to about 70 N. The X-band tracking of MESSENGER and the laser altimetry are the primary data that will be used to measure the planetary shape and gravity field. The laser altimeter, which has an expected range of 1000 to 1200 km, is expected to provide significant data only over the northern hemisphere because of MESSENGER's eccentric orbit. For the southern hemisphere, radio occultation measurements obtained as the spacecraft passes behind the planet as seen from Earth and images obtained with the imaging system will be used to provide the long-wavelength shape of the planet. Gravity, derived from the tracking data, will also have greater resolution in the northern hemisphere, but full global models for both topography and gravity will be obtained at low harmonic order and degree. The limiting factor for both gravity and topography is expected to be knowledge of the spacecraft location. Present estimations are that in a combined tracking, altimetry, and occultation solution the spacecraft position uncertainty is likely to be of order 10 m. This accuracy should be adequate for establishing an initial geodetic coordinate system for Mercury that will enable positioning of imaged features on the surface, determination of

  18. Comparison of damage induced by mercury chloride and ionizing radiation in the susceptible rat model

    International Nuclear Information System (INIS)

    Kim, Ji Hyang; Yoon, Yong Dal; Kim, Jin Kyu

    2003-01-01

    Mercury (Hg), one of the most diffused and hazardous organ-specific environmental contaminants, exists in a wide variety of physical and chemical states. Although the reports indicate that mercury induces a deleterious damage, little has been reported from the investigations of mercury effects in living things. The purpose of this study is to evaluate the effects of mercury chloride and ionizing radiation. Prepubertal male F-344 rats were administered mercury chloride in drinking water throughout the experimental period. Two weeks after whole body irradiation, organs were collected for measuring the induced injury. Serum levels of GOT, GPT, ALP, and LDH were checked in the experimental groups and the hematological analysis was accomplished in plasma. In conclusion, the target organ of mercury chloride seems to be urinary organs and the pattern of damage induced by mercury differs from that of the irradiated group

  19. Recovery of mercury from mercury compounds via electrolytic methods

    Science.gov (United States)

    Grossman, Mark W.; George, William A.

    1988-01-01

    A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg.sub.2 Cl.sub.2 employing as the electrolyte solution a mixture of HCl and H.sub.2 O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H.sub.2 O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds.

  20. Mercury distribution and speciation in soils affected by historic mercury mining

    Czech Academy of Sciences Publication Activity Database

    Hojdová, Maria; Navrátil, Tomáš; Rohovec, Jan; Penížek, V.; Grygar, Tomáš

    2009-01-01

    Roč. 200, 1/4 (2009), s. 89-99 ISSN 0049-6979 R&D Projects: GA AV ČR(CZ) KJB300130615 Institutional research plan: CEZ:AV0Z30130516; CEZ:AV0Z40320502 Keywords : mercury speciation * thermo-desorption analysis * forest soil * contamination * mining * contamination (Czech Republic ) Subject RIV: DD - Geochemistry Impact factor: 1.676, year: 2009

  1. The tectonics of Mercury

    International Nuclear Information System (INIS)

    Melosh, H.J.; Mckinnon, W.B.

    1988-01-01

    The probable tectonic history of Mercury and the relative sequence of events are discussed on the basis of data collected by the Mariner-10 spacecraft. Results indicate that Mercury's tectonic activity was confined to its early history; its endogenic activity was principally due to a small change in the shape of its lithosphere, caused by tidal despinning, and a small change in area caused by shrinkage due to cooling. Exogenic processes, in particular the impact activity, have produced more abundant tectonic features. Many features associated with the Caloris basin are due to loading of Mercury's thick lithosphere by extrusive lavas or subsidence due to magma withdrawal. It is emphasized that tectonic features observed on Mercury yield insight into the earliest tectonic events on planets like Mars and, perhaps, the earth, where subsequent events obscured or erased the most ancient tectonic records

  2. Hans Christian Andersen 200

    Index Scriptorium Estoniae

    2005-01-01

    Hollandi lasteraamatute autorist ja illustraatorist Max Velthuijs'ist (1923-2005). H.C. Anderseni 200. sünniaastapäevale pühendatud lasteraamatunäitusest Rahvusraamatukogus. Eksponeeritakse ka Tiina Reinsalu akvarelle raamatule "Ööbik"

  3. Mercury CEM Calibration

    Energy Technology Data Exchange (ETDEWEB)

    John F. Schabron; Joseph F. Rovani; Susan S. Sorini

    2007-03-31

    The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005, requires that calibration of mercury continuous emissions monitors (CEMs) be performed with NIST-traceable standards. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor generators. The traceability protocol will be written by EPA. Traceability will be based on the actual analysis of the output of each calibration unit at several concentration levels ranging from about 2-40 ug/m{sup 3}, and this analysis will be directly traceable to analyses by NIST using isotope dilution inductively coupled plasma/mass spectrometry (ID ICP/MS) through a chain of analyses linking the calibration unit in the power plant to the NIST ID ICP/MS. Prior to this project, NIST did not provide a recommended mercury vapor pressure equation or list mercury vapor pressure in its vapor pressure database. The NIST Physical and Chemical Properties Division in Boulder, Colorado was subcontracted under this project to study the issue in detail and to recommend a mercury vapor pressure equation that the vendors of mercury vapor pressure calibration units can use to calculate the elemental mercury vapor concentration in an equilibrium chamber at a particular temperature. As part of this study, a preliminary evaluation of calibration units from five vendors was made. The work was performed by NIST in Gaithersburg, MD and Joe Rovani from WRI who traveled to NIST as a Visiting Scientist.

  4. Mercury in human hair

    International Nuclear Information System (INIS)

    Kapauan, P.A.; Cruz, C.C.; Verceluz, F.P.

    1980-10-01

    The analysis of mercury (Hg) in scalp hair obtained from individuals residing in five different localities in the Philippines - Metro Manila, Naga City in Bicol, Bataan, Oriental Mindoro, and Palawan is presented. An overall mean of 1.46 ug/g of hair was obtained for all samples excluding those from Palawan and represents a baseline value.'' In terms of the mercury levels found in hair, the Honda Bay area in Palawan is, relatively, a ''contaminated area.'' (author)

  5. Alterations in CD200-CD200R1 System during EAE Already Manifest at Presymptomatic Stages

    Directory of Open Access Journals (Sweden)

    Tony Valente

    2017-05-01

    occur in the initial phases of multiple sclerosis, and that this early neuronal dysfunction might facilitate the development of neuroinflammation. The increased CD200R1 expression in the EAE model highlights the potential use of targeted agonist molecules as therapeutic tools to control neuroinflammation. In summary, the CD200-CD200R1 system is a potential therapeutic target in multiple sclerosis, and CD200R1 agonists are molecules that may be worth developing in this context.

  6. Evaluation of a sequential extraction process used for determining mercury binding mechanisms to coal combustion byproducts.

    Science.gov (United States)

    Noel, James D; Biswas, Pratim; Giammar, Daniel E

    2007-07-01

    Leaching of mercury from coal combustion byproducts is a concern because of the toxicity of mercury. Leachability of mercury can be assessed by using sequential extraction procedures. Sequential extraction procedures are commonly used to determine the speciation and mobility of trace metals in solid samples and are designed to differentiate among metals bound by different mechanisms and to different solid phases. This study evaluated the selectivity and effectiveness of a sequential extraction process used to determine mercury binding mechanisms to various materials. A six-step sequential extraction process was applied to laboratory-synthesized materials with known mercury concentrations and binding mechanisms. These materials were calcite, hematite, goethite, and titanium dioxide. Fly ash from a full-scale power plant was also investigated. The concentrations of mercury were measured using inductively coupled plasma (ICP) mass spectrometry, whereas the major elements were measured by ICP atomic emission spectrometry. The materials were characterized by X-ray powder diffraction and scanning electron microscopy with energy dispersive spectroscopy. The sequential extraction procedure provided information about the solid phases with which mercury was associated in the solid sample. The procedure effectively extracted mercury from the target phases. The procedure was generally selective in extracting mercury. However, some steps in the procedure extracted mercury from nontarget phases, and others resulted in mercury redistribution. Iron from hematite and goethite was only leached in the reducible and residual extraction steps. Some mercury associated with goethite was extracted in the ion exchangeable step, whereas mercury associated with hematite was extracted almost entirely in the residual step. Calcium in calcite and mercury associated with calcite were primarily removed in the acid-soluble extraction step. Titanium in titanium dioxide and mercury adsorbed onto

  7. Method and apparatus for monitoring mercury emissions

    Science.gov (United States)

    Durham, Michael D.; Schlager, Richard J.; Sappey, Andrew D.; Sagan, Francis J.; Marmaro, Roger W.; Wilson, Kevin G.

    1997-01-01

    A mercury monitoring device that continuously monitors the total mercury concentration in a gas. The device uses the same chamber for converting speciated mercury into elemental mercury and for measurement of the mercury in the chamber by radiation absorption techniques. The interior of the chamber is resistant to the absorption of speciated and elemental mercury at the operating temperature of the chamber.

  8. Mercury contamination from artisanal gold mining in Antioquia, Colombia: The world's highest per capita mercury pollution.

    Science.gov (United States)

    Cordy, Paul; Veiga, Marcello M; Salih, Ibrahim; Al-Saadi, Sari; Console, Stephanie; Garcia, Oseas; Mesa, Luis Alberto; Velásquez-López, Patricio C; Roeser, Monika

    2011-12-01

    The artisanal gold mining sector in Colombia has 200,000 miners officially producing 30tonnes Au/a. In the Northeast of the Department of Antioquia, there are 17 mining towns and between 15,000 and 30,000 artisanal gold miners. Guerrillas and paramilitary activities in the rural areas of Antioquia pushed miners to bring their gold ores to the towns to be processed in Processing Centers or entables. These Centers operate in the urban areas amalgamating the whole ore, i.e. without previous concentration, and later burn gold amalgam without any filtering/condensing system. Based on mercury mass balance in 15 entables, 50% of the mercury added to small ball mills (cocos) is lost: 46% with tailings and 4% when amalgam is burned. In just 5 cities of Antioquia, with a total of 150,000 inhabitants: Segovia, Remedios, Zaragoza, El Bagre, and Nechí, there are 323 entables producing 10-20tonnes Au/a. Considering the average levels of mercury consumption estimated by mass balance and interviews of entables owners, the mercury consumed (and lost) in these 5 municipalities must be around 93tonnes/a. Urban air mercury levels range from 300ng Hg/m(3) (background) to 1million ng Hg/m(3) (inside gold shops) with 10,000ng Hg/m(3) being common in residential areas. The WHO limit for public exposure is 1000ng/m(3). The total mercury release/emissions to the Colombian environment can be as high as 150tonnes/a giving this country the shameful first position as the world's largest mercury polluter per capita from artisanal gold mining. One necessary government intervention is to cut the supply of mercury to the entables. In 2009, eleven companies in Colombia legally imported 130tonnes of metallic mercury, much of it flowing to artisanal gold mines. Entables must be removed from urban centers and technical assistance is badly needed to improve their technology and reduce emissions. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. The Magnetic Field Structure of Mercury's Magnetotail

    Science.gov (United States)

    Rong, Z. J.; Ding, Y.; Slavin, J. A.; Zhong, J.; Poh, G.; Sun, W. J.; Wei, Y.; Chai, L. H.; Wan, W. X.; Shen, C.

    2018-01-01

    In this study, we use the magnetic field data measured by MErcury Surface, Space ENvironment, GEochemistry, and Ranging from 2011 to 2015 to investigate the average magnetic field morphology of Mercury's magnetotail in the down tail 0-3 RM (RM = 2,440 km, Mercury's radius). It is found that Mercury has a terrestrial-like magnetotail; the magnetic field structure beyond 1.5 RM down tail is stretched significantly with typical lobe field 50 nT. A cross-tail current sheet separating the antiparallel field lines of lobes is present in the equatorial plane. The magnetotail width in north-south direction is about 5 RM, while the transverse width is about 4 RM. Thus, the magnetotail shows elongation along the north-south direction. At the cross-tail current sheet center, the normal component of magnetic field (10-20 nT) is much larger than the cross-tail component. The lobe-field-aligned component of magnetic field over current sheet can be well fitted by Harris sheet model. The curvature radius of field lines at sheet center usually reaches a minimum around midnight (100-200 km) with stronger current density (40-50 nA/m2), while the curvature radius increases toward both flanks (400-600 km) with the decreased current density (about 20 nA/m2). The half-thickness of current sheet around midnight is about 0.25 RM or 600 km, and the inner edge of current sheet is located at the down tail about 1.5 RM. Our results about the field structure in the near Mercury's tail show an evident dawn-dusk asymmetry as that found in the Earth's magnetotail, but reasons should be different. Possible reasons are discussed.

  10. Mercury pollution in Malaysia.

    Science.gov (United States)

    Hajeb, Parvaneh; Jinap, S; Ismail, Ahmad; Mahyudin, Nor Ainy

    2012-01-01

    Although several studies have been published on levels of mercury contamination of the environment, and of food and human tissues in Peninsular Malaysia, there is a serious dearth of research that has been performed in East Malaysia (Sabah and Sarawak). Industry is rapidly developing in East Malaysia, and, hence, there is a need for establishing baseline levels of mercury contamination in environmental media in that part of the country by performing monitoring studies. Residues of total mercury and inorganic in food samples have been determined in nearly all previous studies that have been conducted; however, few researchers have analyzed samples for the presence of methlymercury residues. Because methylmercury is the most toxic form of mercury, and because there is a growing public awareness of the risk posed by methylmercury exposure that is associated with fish and seafood consumption, further monitoring studies on methylmercury in food are also essential. From the results of previous studies, it is obvious that the economic development in Malaysia, in recent years, has affected the aquatic environment of the country. Primary areas of environmental concern are centered on the rivers of the west Peninsular Malaysian coast, and the coastal waters of the Straits of Malacca, wherein industrial activities are rapidly expanding. The sources of existing mercury input to both of these areas of Malaysia should be studied and identified. Considering the high levels of mercury that now exists in human tissues, efforts should be continued, and accelerated in the future, if possible, to monitor mercury contamination levels in the coastal states, and particularly along the west Peninsular Malaysian coast. Most studies that have been carried out on mercury residues in environmental samples are dated, having been conducted 20-30 years ago; therefore, the need to collect much more and more current data is urgent. Furthermore, establishing baseline levels of mercury exposure to

  11. Simultaneous Removal of NOx and Mercury in Low Temperature Selective Catalytic and Adsorptive Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Neville G. Pinto; Panagiotis G. Smirniotis

    2006-03-31

    The results of a 18-month investigation to advance the development of a novel Low Temperature Selective Catalytic and Adsorptive Reactor (LTSCAR), for the simultaneous removal of NO{sub x} and mercury (elemental and oxidized) from flue gases in a single unit operation located downstream of the particulate collectors, are reported. In the proposed LTSCAR, NO{sub x} removal is in a traditional SCR mode but at low temperature, and, uniquely, using carbon monoxide as a reductant. The concomitant capture of mercury in the unit is achieved through the incorporation of a novel chelating adsorbent. As conceptualized, the LTSCAR will be located downstream of the particulate collectors (flue gas temperature 140-160 C) and will be similar in structure to a conventional SCR. That is, it will have 3-4 beds that are loaded with catalyst and adsorbent allowing staged replacement of catalyst and adsorbent as required. Various Mn/TiO{sub 2} SCR catalysts were synthesized and evaluated for their ability to reduce NO at low temperature using CO as the reductant. It has been shown that with a suitably tailored catalyst more than 65% NO conversion with 100% N{sub 2} selectivity can be achieved, even at a high space velocity (SV) of 50,000 h-1 and in the presence of 2 v% H{sub 2}O. Three adsorbents for oxidized mercury were developed in this project with thermal stability in the required range. Based on detailed evaluations of their characteristics, the mercaptopropyltrimethoxysilane (MPTS) adsorbent was found to be most promising for the capture of oxidized mercury. This adsorbent has been shown to be thermally stable to 200 C. Fixed-bed evaluations in the targeted temperature range demonstrated effective removal of oxidized mercury from simulated flue gas at very high capacity ({approx}>58 mg Hg/g adsorbent). Extension of the capability of the adsorbent to elemental mercury capture was pursued with two independent approaches: incorporation of a novel nano-layer on the surface of the

  12. Mercury Emissions: The Global Context

    Science.gov (United States)

    Mercury emissions are a global problem that knows no national or continental boundaries. Mercury that is emitted to the air can travel thousands of miles in the atmosphere before it is eventually deposited back to the earth.

  13. Mercury inclusion a waste processing; Suigin ganyu haikibutsu no shori

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-06-05

    BNL (Brookhaven National Laboratory) developed process (SPSS) which granularly stabilized the mercury contamination material including the radioactive material. In the SPSS Inc. method, the sulfur similarly is made to react on the mercury with the amalgamation, and mercury sulfide of low vapor pressure is formed at the low solubility. In the new process, in this amalgamation, the dispersion of the fine powder becomes a problem, and the pollutant mixes with 'the sulfur (95%)-dicyclopentadiene (5%) mixture', and it pours in melting post-container heated to 120 degrees C. The possible uniform composition lump fixes mercury and radioisotope as the result. 200 of the EPA standard in the product by the pilot study the 0.5-3ppb mercury which drastically fell below ppb was contained. In addition, BNL has planned the test operation in the commercial. In the future, the processing of a mercury inclusion waste in the radioactive waste disposal authorization facilities will become possible, if the actual/real process is established. (translated by NEDO)

  14. Mercury's magnetic field and interior

    International Nuclear Information System (INIS)

    Connerney, J.E.P.; Ness, N.F.

    1988-01-01

    The magnetic-field data collected on Mercury by the Mariner-10 spacecraft present substantial evidence for an intrinsic global magnetic field. However, studies of Mercury's thermal evolution show that it is most likely that the inner core region of Mercury solidified or froze early in the planet's history. Thus, the explanation of Mercury's magnetic field in the framework of the traditional planetary dynamo is less than certain

  15. 34 CFR 200.68-200.69 - [Reserved

    Science.gov (United States)

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false [Reserved] 200.68-200.69 Section 200.68-200.69 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING THE ACADEMIC ACHIEVEMENT OF THE DISADVANTAGED Improving...

  16. Reference Atmosphere for Mercury

    Science.gov (United States)

    Killen, Rosemary M.

    2002-01-01

    We propose that Ar-40 measured in the lunar atmosphere and that in Mercury's atmosphere is due to current diffusion into connected pore space within the crust. Higher temperatures at Mercury, along with more rapid loss from the atmosphere will lead to a smaller column abundance of argon at Mercury than at the Moon, given the same crustal abundance of potassium. Because the noble gas abundance in the Hermean atmosphere represents current effusion, it is a direct measure of the crustal potassium abundance. Ar-40 in the atmospheres of the planets is a measure of potassium abundance in the interiors, since Ar-40 is a product of radiogenic decay of K-40 by electron capture with the subsequent emission of a 1.46 eV gamma-ray. Although the Ar-40 in the Earth's atmosphere is expected to have accumulated since the late bombardment, Ar-40 in the atmospheres of Mercury and the Moon is eroded quickly by photoionization and electron impact ionization. Thus, the argon content in the exospheres of the Moon and Mercury is representative of current effusion rather than accumulation over the lifetime of the planet.

  17. Mercury content of edible mushrooms

    Energy Technology Data Exchange (ETDEWEB)

    Woidich, H.; Pfannhauser, W.

    1975-05-01

    The mercury content of edible fungi is different. Relatively high burdened are Boletus and Agaricus campestris. A minimum of mercury is found in Russula, Agaricus bisporus and Cantharellus cibarius. The possibilities of mercury uptake and the potential cumulation mechanism is discussed. 8 references, 3 tables.

  18. Mercury (Environmental Health Student Portal)

    Science.gov (United States)

    ... Water Waterborne Diseases & Illnesses Water Cycle Water Treatment Mercury The Basics Mercury — sometimes called quicksilver — is a natural metal. It’s ... to breathe it in without knowing it. When mercury combines with other chemical elements, it creates compounds, ...

  19. Sensing Mercury for Biomedical and Environmental Monitoring

    Directory of Open Access Journals (Sweden)

    Julia Xiaojun Zhao

    2009-07-01

    Full Text Available Mercury is a very toxic element that is widely spread in the atmosphere, lithosphere, and surface water. Concentrated mercury poses serious problems to human health, as bioaccumulation of mercury within the brain and kidneys ultimately leads to neurological diseases. To control mercury pollution and reduce mercury damage to human health, sensitive determination of mercury is important. This article summarizes some current sensors for the determination of both abiotic and biotic mercury. A wide array of sensors for monitoring mercury is described, including biosensors and chemical sensors, while piezoelectric and microcantilever sensors are also described. Additionally, newly developed nanomaterials offer great potential for fabricating novel mercury sensors. Some of the functional fluorescent nanosensors for the determination of mercury are covered. Afterwards, the in vivo determination of mercury and the characterization of different forms of mercury are discussed. Finally, the future direction for mercury detection is outlined, suggesting that nanomaterials may provide revolutionary tools in biomedical and environmental monitoring of mercury.

  20. Comment: 200 [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available 合データベースセンター) Photo: Takeru Nakazato (Database Center for Life Science) nakazato 2009/11/04 17:26:47 2010/01/14 20:11:35 ... ...Japanese tree frog Hyla japonica Hyla_japonica_L.png 200.png Takeru Nakazato (Database Center for Life Scien...ce) licensed under CC Attribution2.1 Japan ニホンアマガエル Hyla japonica 撮影:仲里猛留(ライフサイエンス統

  1. Mercury-induced motor and sensory neurotoxicity: systematic review of workers currently exposed to mercury vapor.

    Science.gov (United States)

    Fields, Cheryl A; Borak, Jonathan; Louis, Elan D

    2017-11-01

    The neurotoxicity of elemental mercury (Hg 0 ) is well-recognized, but it is uncertain whether and for how long neurotoxicity persists; among studies that evaluated previously exposed workers, only one examined workers during and also years after exposure ceased. The aim of this review is to document the type, frequency, and dose-relatedness of objective neurological effects in currently exposed mercury workers and thereby provide first approximations of the effects one would have expected in previously exposed workers evaluated during exposure. We systematically reviewed studies of neurotoxicity in currently exposed mercury workers identified by searching MEDLINE (1950-2015), government reports, textbook chapters, and references cited therein; dental cohorts were not included. Outcomes on physical examination (PE), neurobehavioral (NB) tests, and electrophysiological studies were extracted and evaluated for consistency and dose-relatedness. Forty-five eligible studies were identified, comprising over 3000 workers chronically exposed to a range of Hg 0 concentrations (0.002-1.7 mg/m 3 ). Effects that demonstrated consistency across studies and increased frequency across urine mercury levels (200 μg/L, while NB testing is more appropriate for those with lower U Hg levels. They also provide benchmarks to which findings in workers with historical exposure can be compared.

  2. Water displacement mercury pump

    Science.gov (United States)

    Nielsen, M.G.

    1984-04-20

    A water displacement mercury pump has a fluid inlet conduit and diffuser, a valve, a pressure cannister, and a fluid outlet conduit. The valve has a valve head which seats in an opening in the cannister. The entire assembly is readily insertable into a process vessel which produces mercury as a product. As the mercury settles, it flows into the opening in the cannister displacing lighter material. When the valve is in a closed position, the pressure cannister is sealed except for the fluid inlet conduit and the fluid outlet conduit. Introduction of a lighter fluid into the cannister will act to displace a heavier fluid from the cannister via the fluid outlet conduit. The entire pump assembly penetrates only a top wall of the process vessel, and not the sides or the bottom wall of the process vessel. This insures a leak-proof environment and is especially suitable for processing of hazardous materials.

  3. Marine foraging ecology influences mercury bioaccumulation in deep-diving northern elephant seals.

    Science.gov (United States)

    Peterson, Sarah H; Ackerman, Joshua T; Costa, Daniel P

    2015-07-07

    Mercury contamination of oceans is prevalent worldwide and methylmercury concentrations in the mesopelagic zone (200-1000 m) are increasing more rapidly than in surface waters. Yet mercury bioaccumulation in mesopelagic predators has been understudied. Northern elephant seals (Mirounga angustirostris) biannually travel thousands of kilometres to forage within coastal and open-ocean regions of the northeast Pacific Ocean. We coupled satellite telemetry, diving behaviour and stable isotopes (carbon and nitrogen) from 77 adult females, and showed that variability among individuals in foraging location, diving depth and δ(13)C values were correlated with mercury concentrations in blood and muscle. We identified three clusters of foraging strategies, and these resulted in substantially different mercury concentrations: (i) deeper-diving and offshore-foraging seals had the greatest mercury concentrations, (ii) shallower-diving and offshore-foraging seals had intermediate levels, and (iii) coastal and more northerly foraging seals had the lowest mercury concentrations. Additionally, mercury concentrations were lower at the end of the seven-month-long foraging trip (n = 31) than after the two-month- long post-breeding trip (n = 46). Our results indicate that foraging behaviour influences mercury exposure and mesopelagic predators foraging in the northeast Pacific Ocean may be at high risk for mercury bioaccumulation. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  4. Sulfur rich microporous polymer enables rapid and efficient removal of mercury(II) from water.

    Science.gov (United States)

    Xu, Dan; Wu, Winston Duo; Qi, Hao-Jun; Yang, Rui-Xia; Deng, Wei-Qiao

    2018-04-01

    Design and synthesis of adsorbents for efficient decontamination of hazardous contaminants Hg 2+ from wastewater, based on a facile and economical strategy, is an attractive target. Here, a novel sulfur rich microporous polymer (sulfur content of 31.4 wt %) with high surface area as well as densely populated sulfur atom with fast accessibility was reported to remove mercury (II) from water. The as prepared polymer (SMP) exhibited high binding affinity, high adsorption capacities, rapid adsorption kinetics, and good recyclability for Hg 2+ . The adsorption capacity of SMP was 595.2 mg g -1 . Furthermore, SMP could reduce trace concentrations of Hg 2+ from 200 p. p. b. to a level below drinking water standards (2 p. p. b.) within 3 min. This work allows large-scale production of sulfur rich porous materials for the practical application in water treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Mercury CEM Calibration

    Energy Technology Data Exchange (ETDEWEB)

    John Schabron; Joseph Rovani; Mark Sanderson

    2008-02-29

    Mercury continuous emissions monitoring systems (CEMS) are being implemented in over 800 coal-fired power plant stacks. The power industry desires to conduct at least a full year of monitoring before the formal monitoring and reporting requirement begins on January 1, 2009. It is important for the industry to have available reliable, turnkey equipment from CEM vendors. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor generators. The generators are used to calibrate mercury CEMs at power plant sites. The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005 requires that calibration be performed with NIST-traceable standards (Federal Register 2007). Traceability procedures will be defined by EPA. An initial draft traceability protocol was issued by EPA in May 2007 for comment. In August 2007, EPA issued an interim traceability protocol for elemental mercury generators (EPA 2007). The protocol is based on the actual analysis of the output of each calibration unit at several concentration levels ranging initially from about 2-40 {micro}g/m{sup 3} elemental mercury, and in the future down to 0.2 {micro}g/m{sup 3}, and this analysis will be directly traceable to analyses by NIST. The document is divided into two separate sections. The first deals with the qualification of generators by the vendors for use in mercury CEM calibration. The second describes the procedure that the vendors must use to certify the generator models that meet the qualification specifications. The NIST traceable certification is performance based, traceable to analysis using isotope dilution inductively coupled plasma/mass spectrometry performed by NIST in Gaithersburg, MD. The

  6. Removal of Elemental Mercury from a Gas Stream Facilitated by a Non-Thermal Plasma Device

    Energy Technology Data Exchange (ETDEWEB)

    Charles Mones

    2006-12-01

    Mercury generated from anthropogenic sources presents a difficult environmental problem. In comparison to other toxic metals, mercury has a low vaporization temperature. Mercury and mercury compounds are highly toxic, and organic forms such as methyl mercury can be bio-accumulated. Exposure pathways include inhalation and transport to surface waters. Mercury poisoning can result in both acute and chronic effects. Most commonly, chronic exposure to mercury vapor affects the central nervous system and brain, resulting in neurological damage. The CRE technology employs a series of non-thermal, plasma-jet devices to provide a method for elemental mercury removal from a gas phase by targeting relevant chemical reactions. The technology couples the known chemistry of converting elemental mercury to ionic compounds by mercury-chlorine-oxygen reactions with the generation of highly reactive species in a non-thermal, atmospheric, plasma device. The generation of highly reactive metastable species in a non-thermal plasma device is well known. The introduction of plasma using a jet-injection device provides a means to contact highly reactive species with elemental mercury in a manner to overcome the kinetic and mass-transfer limitations encountered by previous researchers. To demonstrate this technology, WRI has constructed a plasma test facility that includes plasma reactors capable of using up to four plasma jets, flow control instrumentation, an integrated control panel to operate the facility, a mercury generation system that employs a temperature controlled oven and permeation tube, combustible and mercury gas analyzers, and a ductless fume hood designed to capture fugitive mercury emissions. Continental Research and Engineering (CR&E) and Western Research Institute (WRI) successfully demonstrated that non-thermal plasma containing oxygen and chlorine-oxygen reagents could completely convert elemental mercury to an ionic form. These results demonstrate potential the

  7. Assessment of Mercury in Fish Tissue from Select Lakes of Northeastern Oregon

    Science.gov (United States)

    A fish tissue study was conducted in five northeastern Oregon reservoirs to evaluate mercury concentrations in an area where elevated atmospheric mercury deposition had been predicted by a national EPA model, but where tissue data were sparse. The study targeted resident predator...

  8. IRIS (Version 200)

    International Nuclear Information System (INIS)

    Pansart, J.P.

    1987-01-01

    IRIS is a Monte Carlo generator of nucleon-nucleus and nucleus-nucleus interactions at high energy (≥50 GeV per nucleon for the projectile on a fixed target). The physics basis of the generator is the exchange of colour. (orig./HSI)

  9. Experimental cross-sections for proton induced nuclear reactions on mercury up to 65 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Hermanne, A., E-mail: aherman@vub.ac.be [Cyclotron Laboratory, Vrije Universiteit Brussel (VUB), Brussels (Belgium); Tárkányi, F.; Takács, S.; Ditrói, F.; Szücs, Z.; Brezovcsik, K. [Institute of Nuclear Research, Hungarian Academy of Sciences (ATOMKI), Debrecen (Hungary)

    2016-07-01

    Cross-sections for formation of activation products induced by protons on natural mercury targets were measured. Results for {sup 196m,196g,197g}(cum), {sup 198m,198g,199g}(cum), {sup 200g}(cum), {sup 201,202}Tl, {sup 194g}(cum), {sup 195g}(cum), {sup 196g}(cum), {sup 198m,199g}(cum) Au and {sup 195m,197m,203}Hg are presented up to 65 MeV incident particle energy, many of these for the first time. The experimental data are compared with literature values and with the predictions of the TALYS 1.6 code (results taken from TENDL-2015 on-line library), thick target yields were derived and possible applications in biomedical sciences are discussed.

  10. Method and apparatus for sampling atmospheric mercury

    Science.gov (United States)

    Trujillo, Patricio E.; Campbell, Evan E.; Eutsler, Bernard C.

    1976-01-20

    A method of simultaneously sampling particulate mercury, organic mercurial vapors, and metallic mercury vapor in the working and occupational environment and determining the amount of mercury derived from each such source in the sampled air. A known volume of air is passed through a sampling tube containing a filter for particulate mercury collection, a first adsorber for the selective adsorption of organic mercurial vapors, and a second adsorber for the adsorption of metallic mercury vapor. Carbon black molecular sieves are particularly useful as the selective adsorber for organic mercurial vapors. The amount of mercury adsorbed or collected in each section of the sampling tube is readily quantitatively determined by flameless atomic absorption spectrophotometry.

  11. Transient analysis of mercury experimental loop using the RELAP5 code. 3rd report. Transient analysis using mercury properties

    International Nuclear Information System (INIS)

    Kinoshita, Hidetaka; Kaminaga, Masanori; Hino, Ryutaro

    2000-02-01

    In order to promote the Neutron Science Project of JAERI, the design of a 5MW-spallation target system is in progress with the purpose of producing a practical neutron application while at the same time adhering to the highest levels of safety. To establish the safety of the target system, it is important to understand the transient behaviors during anticipated operational events of the system, and to design the safety protection systems for the safe termination of the transients. This report presents the analytical results of transient behaviors in the mercury experimental loop using mercury properties. At first, the analytical pressure distributions were compared with experimental data measured with the mercury experimental loop. The modeling data were modified to reproduce the actual pressure distributions of the mercury experimental loop. Then a loss of forced convection and a loss of coolant accident were analyzed. In the case of the pump trip, the transient analysis was conducted using two types of mercury pumps, the mechanical type pump with moment of inertia, and the electrical-magnetic type pump without moment of inertia. The results show there was no clear difference in the two analyses, since the mercury had a large inertia, which was 13.5 times that of the water. Moreover, in the case of a pipe rupture at the pump exit, a moderate pressure decrease was confirmed when a small breakage area existed in which the coolant flowed out gradually. Based on these results, it was appeared that the transient fluctuation of pressure in the mercury loop would not become large and accidents would have to be detected by small fluctuations in pressure. Based on these analyses, we plan to conduct a simulation test to verify the RELAP5 code, and then the analysis of a full-scale mercury system will be performed. (author)

  12. Evaluation of Sorbent Injection for Mercury Control

    Energy Technology Data Exchange (ETDEWEB)

    Sharon Sjostrom

    2006-04-30

    The power industry in the U.S. is faced with meeting new regulations to reduce the emissions of mercury compounds from coal-fired plants. These regulations are directed at the existing fleet of nearly 1,100 boilers. These plants are relatively old with an average age of over 40 years. Although most of these units are capable of operating for many additional years, there is a desire to minimize large capital expenditures because of the reduced (and unknown) remaining life of the plant to amortize the project. Injecting a sorbent such as powdered activated carbon into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. This is the final site report for tests conducted at DTE Energy's Monroe Power Plant, one of five sites evaluated in this DOE/NETL program. The overall objective of the test program was to evaluate the capabilities of activated carbon injection at five plants: Sunflower Electric's Holcomb Station Unit 1, AmerenUE's Meramec Station Unit 2, Missouri Basin Power Project's Laramie River Station Unit 3, Detroit Edison's Monroe Power Plant Unit 4, and AEP's Conesville Station Unit 6. These plants have configurations that together represent 78% of the existing coal-fired generation plants. The goals for the program established by DOE/NETL were to reduce the uncontrolled mercury emissions by 50 to 70% at a cost 25 to 50% lower than the target established by DOE of $60,000/lb mercury removed. The results from Monroe indicate that using DARCO{reg_sign} Hg would result in higher mercury removal (80%) at a sorbent cost of $18,000/lb mercury, or 70% lower than the benchmark. These results demonstrate that the goals established by DOE/NETL were exceeded during this test program. The increase in mercury removal over baseline conditions is defined for this program as a comparison in the outlet emissions measured using the Ontario Hydro method during the baseline

  13. Mercury analysis in hair

    DEFF Research Database (Denmark)

    Esteban, Marta; Schindler, Birgit Karin; Jiménez, José Antonio

    2015-01-01

    laboratories. Training sessions were organized for field workers and four external quality-assessment exercises (ICI/EQUAS), followed by the corresponding web conferences, were organized between March 2011 and February 2012. ICI/EQUAS used native hair samples at two mercury concentration ranges (0...

  14. Mercury exposure in Ireland

    DEFF Research Database (Denmark)

    Cullen, Elizabeth; Evans, David S; Davidson, Fred

    2014-01-01

    of a study to Coordinate and Perform Human Biomonitoring on a European Scale (DEMOCOPHES) pilot biomonitoring study. METHODS: Hair mercury concentrations were determined from a convenience sample of 120 mother/child pairs. Mothers also completed a questionnaire. Rigorous quality assurance within DEMOCOPHES...

  15. Metabolic models for methyl and inorganic mercury

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, S.R.; Purdue, P.

    1984-03-01

    Following the outbreak of mercury poisoning in Minimata, Japan (1953-60), much work has been done on the toxicology of mercury - in particular methyl mercury. In this paper, the authors derive two compartmental models for the metabolism of methyl mercury and inorganic mercury based upon the data which have been collected since 1960.

  16. [Mercury in vaccines].

    Science.gov (United States)

    Hessel, Luc

    2003-01-01

    Thiomersal, also called thimerosal, is an ethyl mercury derivative used as a preservative to prevent bacterial contamination of multidose vaccine vials after they have been opened. Exposure to low doses of thiomersal has essentially been associated with hypersensitivity reactions. Nevertheless there is no evidence that allergy to thiomersal could be induced by thiomersal-containing vaccines. Allergy to thiomersal is usually of delayed-hypersensitivity type, but its detection through cutaneous tests is not very reliable. Hypersensitivity to thiomersal is not considered as a contraindication to the use of thiomersal-containing vaccines. In 1999 in the USA, thiomersal was present in approximately 30 different childhood vaccines, whereas there were only 2 in France. Although there were no evidence of neurological toxicity in infants related to the use of thiomersal-containing vaccines, the FDA considered that the cumulative dose of mercury received by young infants following vaccination was high enough (although lower than the FDA threshold for methyl mercury) to request vaccine manufacturers to remove thiomersal from vaccine formulations. Since 2002, all childhood vaccines used in Europe and the USA are thiomersal-free or contain only minute amounts of thiomersal. Recently published studies have shown that the mercury levels in the blood, faeces and urine of children who had received thiomersal-containing vaccines were much lower than those accepted by the American Environmental Protection Agency. It has also been demonstrated that the elimination of mercury in children was much faster than what was expected on the basis of studies conducted with methyl mercury originating from food. Recently, the hypothesis that mercury contained in vaccines could be the cause of autism and other neurological developmental disorders created a new debate in the medical community and the general public. To date, none of the epidemiological studies conducted in Europe and elsewhere

  17. Mercury Information Clearinghouse

    Energy Technology Data Exchange (ETDEWEB)

    Chad A. Wocken; Michael J. Holmes; Dennis L. Laudal; Debra F. Pflughoeft-Hassett; Greg F. Weber; Nicholas V. C. Ralston; Stanley J. Miller; Grant E. Dunham; Edwin S. Olson; Laura J. Raymond; John H. Pavlish; Everett A. Sondreal; Steven A. Benson

    2006-03-31

    The Canadian Electricity Association (CEA) identified a need and contracted the Energy & Environmental Research Center (EERC) to create and maintain an information clearinghouse on global research and development activities related to mercury emissions from coal-fired electric utilities. With the support of CEA, the Center for Air Toxic Metals{reg_sign} (CATM{reg_sign}) Affiliates, and the U.S. Department of Energy (DOE), the EERC developed comprehensive quarterly information updates that provide a detailed assessment of developments in the various areas of mercury monitoring, control, policy, and research. A total of eight topical reports were completed and are summarized and updated in this final CEA quarterly report. The original quarterly reports can be viewed at the CEA Web site (www.ceamercuryprogram.ca). In addition to a comprehensive update of previous mercury-related topics, a review of results from the CEA Mercury Program is provided. Members of Canada's coal-fired electricity generation sector (ATCO Power, EPCOR, Manitoba Hydro, New Brunswick Power, Nova Scotia Power Inc., Ontario Power Generation, SaskPower, and TransAlta) and CEA, have compiled an extensive database of information from stack-, coal-, and ash-sampling activities. Data from this effort are also available at the CEA Web site and have provided critical information for establishing and reviewing a mercury standard for Canada that is protective of environment and public health and is cost-effective. Specific goals outlined for the CEA mercury program included the following: (1) Improve emission inventories and develop management options through an intensive 2-year coal-, ash-, and stack-sampling program; (2) Promote effective stack testing through the development of guidance material and the support of on-site training on the Ontario Hydro method for employees, government representatives, and contractors on an as-needed basis; (3) Strengthen laboratory analytical capabilities through

  18. The importance of catchment vegetation for lake sediment mercury records

    Science.gov (United States)

    Rydberg, Johan; Rösch, Manfred; Heinz, Emanuel; Biester, Harald

    2014-05-01

    In this study we have used a long, Holocene, sediment profile from a small headwater lake in Southern Germany to determine how changes in the vegetation affected the sediment accumulation in general and the accumulation of mercury in particular. The sediment samples were analyzed for their content of total mercury, organic matter quality/quantity and geochemical composition, and the vegetation development was determined using pollen analysis. Over the course of the Holocene, two major shifts in vegetation occurred, both coincide with changes in mercury accumulation. The period prior to 9000 BP was dominated by non-forest vegetation (e.g., Corylus avellana), and mercury concentrations around 60 ng g-1 (90 μg m-2 yr-1). About 8500 BP there was a shift to forest vegetation (mainly Quercus robur), which coincides with increases in both mercury concentrations and accumulation rates (115 ng g-1 and 140 μg m-2 yr-1, respectively). This vegetation shift also drastically decreased the influx of mineral particles to the lake, likely because the development of a closed forest decreased soil erosion. During the following 3500 years - when the vegetation remained dominated by Quercus robur - mercury concentrations were stable around 115 ng g-1, while mercury accumulation rates decreased to about 110 μg m-2 yr-1 due to a gradual decrease in sediment accumulation during the latter part of this period. Around 5000 BP there is a second shift in the vegetation as Quercus robur is replaced by Fagus sylvatica and Abies alba as the dominant tree species, and again this shift leads to an increase in both mercury concentrations and mercury accumulation rates (200 ng g-1 and 140 μg m-2 yr-1, respectively). This shows that the vegetation - and not only the concentration of mercury in the atmosphere - has an influence on the amount of mercury that is accumulated in a lake's sediment. Firstly, the vegetation will influence the interception of mercury, and other atmospherically derived

  19. Small Mercury Relativity Orbiter

    Science.gov (United States)

    Bender, Peter L.; Vincent, Mark A.

    1989-01-01

    The accuracy of solar system tests of gravitational theory could be very much improved by range and Doppler measurements to a Small Mercury Relativity Orbiter. A nearly circular orbit at roughly 2400 km altitude is assumed in order to minimize problems with orbit determination and thermal radiation from the surface. The spacecraft is spin-stabilized and has a 30 cm diameter de-spun antenna. With K-band and X-band ranging systems using a 50 MHz offset sidetone at K-band, a range accuracy of 3 cm appears to be realistically achievable. The estimated spacecraft mass is 50 kg. A consider-covariance analysis was performed to determine how well the Earth-Mercury distance as a function of time could be determined with such a Relativity Orbiter. The minimum data set is assumed to be 40 independent 8-hour arcs of tracking data at selected times during a two year period. The gravity field of Mercury up through degree and order 10 is solved for, along with the initial conditions for each arc and the Earth-Mercury distance at the center of each arc. The considered parameters include the gravity field parameters of degree 11 and 12 plus the tracking station coordinates, the tropospheric delay, and two parameters in a crude radiation pressure model. The conclusion is that the Earth-Mercury distance can be determined to 6 cm accuracy or better. From a modified worst-case analysis, this would lead to roughly 2 orders of magnitude improvement in the knowledge of the precession of perihelion, the relativistic time delay, and the possible change in the gravitational constant with time.

  20. Gravity, Topography, and Magnetic Field of Mercury from Messenger

    Science.gov (United States)

    Neumann, Gregory A.; Solomon, Sean C.; Zuber, Maria T.; Phillips, Roger J.; Barnouin, Olivier; Ernst, Carolyn; Goosens, Sander; Hauck, Steven A., II; Head, James W., III; Johnson, Catherine L.; hide

    2012-01-01

    On 18 March 2011, the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft was inserted into a 12-hour, near-polar orbit around Mercury, with an initial periapsis altitude of 200 km, initial periapse latitude of 60 deg N, and apoapsis at approximately 15,200 km altitude in the southern hemisphere. This orbit has permitted the mapping of regional gravitational structure in the northern hemisphere, and laser altimetry from the MESSENGER spacecraft has yielded a geodetically controlled elevation model for the same hemisphere. The shape of a planet combined with gravity provides fundamental information regarding its internal structure and geologic and thermal evolution. Elevations in the northern hemisphere exhibit a unimodal distribution with a dynamic range of 9.63 km, less than that of the Moon (19.9 km), but consistent with Mercury's higher surface gravitational acceleration. After one Earth-year in orbit, refined models of gravity and topography have revealed several large positive gravity anomalies that coincide with major impact basins. These candidate mascons have anomalies that exceed 100 mGal and indicate substantial crustal thinning and superisostatic uplift of underlying mantle. An additional uncompensated 1000-km-diameter gravity and topographic high at 68 deg N, 33 deg E lies within Mercury's northern volcanic plains. Mercury's northern hemisphere crust is generally thicker at low latitudes than in the polar region. The low-degree gravity field, combined with planetary spin parameters, yields the moment of inertia C/MR2 = 0.353 +/- 0.017, where M=3.30 x 10(exp 23) kg and R=2440 km are Mercury's mass and radius, and a ratio of the moment of inertia of Mercury's solid outer shell to that of the planet of Cm/C = 0.452 +/- 0.035. One proposed model for Mercury's radial density distribution consistent with these results includes silicate crust and mantle layers overlying a dense solid (possibly Fe-S) layer, a liquid Fe

  1. Mercury Phase II Study - Mercury Behavior in Salt Processing Flowsheet

    Energy Technology Data Exchange (ETDEWEB)

    Jain, V. [Savannah River Remediation, LLC., Aiken, SC (United States); Shah, H. [Savannah River Remediation, LLC., Aiken, SC (United States). Sludge and Salt Planning; Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wilmarth, W. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-07-25

    Mercury (Hg) in the Savannah River Site Liquid Waste System (LWS) originated from decades of canyon processing where it was used as a catalyst for dissolving the aluminum cladding of reactor fuel. Approximately 60 metric tons of mercury is currently present throughout the LWS. Mercury has long been a consideration in the LWS, from both hazard and processing perspectives. In February 2015, a Mercury Program Team was established at the request of the Department of Energy to develop a comprehensive action plan for long-term management and removal of mercury. Evaluation was focused in two Phases. Phase I activities assessed the Liquid Waste inventory and chemical processing behavior using a system-by-system review methodology, and determined the speciation of the different mercury forms (Hg+, Hg++, elemental Hg, organomercury, and soluble versus insoluble mercury) within the LWS. Phase II activities are building on the Phase I activities, and results of the LWS flowsheet evaluations will be summarized in three reports: Mercury Behavior in the Salt Processing Flowsheet (i.e. this report); Mercury Behavior in the Defense Waste Processing Facility (DWPF) Flowsheet; and Mercury behavior in the Tank Farm Flowsheet (Evaporator Operations). The evaluation of the mercury behavior in the salt processing flowsheet indicates, inter alia, the following: (1) In the assembled Salt Batches 7, 8 and 9 in Tank 21, the total mercury is mostly soluble with methylmercury (MHg) contributing over 50% of the total mercury. Based on the analyses of samples from 2H Evaporator feed and drop tanks (Tanks 38/43), the source of MHg in Salt Batches 7, 8 and 9 can be attributed to the 2H evaporator concentrate used in assembling the salt batches. The 2H Evaporator is used to evaporate DWPF recycle water. (2) Comparison of data between Tank 21/49, Salt Solution Feed Tank (SSFT), Decontaminated Salt Solution Hold Tank (DSSHT), and Tank 50 samples suggests that the total mercury as well as speciated

  2. Mercury Phase II Study - Mercury Behavior in Salt Processing Flowsheet

    International Nuclear Information System (INIS)

    Jain, V.; Shah, H.; Wilmarth, W. R.

    2016-01-01

    Mercury (Hg) in the Savannah River Site Liquid Waste System (LWS) originated from decades of canyon processing where it was used as a catalyst for dissolving the aluminum cladding of reactor fuel. Approximately 60 metric tons of mercury is currently present throughout the LWS. Mercury has long been a consideration in the LWS, from both hazard and processing perspectives. In February 2015, a Mercury Program Team was established at the request of the Department of Energy to develop a comprehensive action plan for long-term management and removal of mercury. Evaluation was focused in two Phases. Phase I activities assessed the Liquid Waste inventory and chemical processing behavior using a system-by-system review methodology, and determined the speciation of the different mercury forms (Hg+, Hg++, elemental Hg, organomercury, and soluble versus insoluble mercury) within the LWS. Phase II activities are building on the Phase I activities, and results of the LWS flowsheet evaluations will be summarized in three reports: Mercury Behavior in the Salt Processing Flowsheet (i.e. this report); Mercury Behavior in the Defense Waste Processing Facility (DWPF) Flowsheet; and Mercury behavior in the Tank Farm Flowsheet (Evaporator Operations). The evaluation of the mercury behavior in the salt processing flowsheet indicates, inter alia, the following: (1) In the assembled Salt Batches 7, 8 and 9 in Tank 21, the total mercury is mostly soluble with methylmercury (MHg) contributing over 50% of the total mercury. Based on the analyses of samples from 2H Evaporator feed and drop tanks (Tanks 38/43), the source of MHg in Salt Batches 7, 8 and 9 can be attributed to the 2H evaporator concentrate used in assembling the salt batches. The 2H Evaporator is used to evaporate DWPF recycle water. (2) Comparison of data between Tank 21/49, Salt Solution Feed Tank (SSFT), Decontaminated Salt Solution Hold Tank (DSSHT), and Tank 50 samples suggests that the total mercury as well as speciated

  3. A mercury transport and fate model (LM2-mercury) for mass budget assessment of mercury cycling in Lake Michigan

    Science.gov (United States)

    LM2-Mercury, a mercury mass balance model, was developed to simulate and evaluate the transport, fate, and biogeochemical transformations of mercury in Lake Michigan. The model simulates total suspended solids (TSS), disolved organic carbon (DOC), and total, elemental, divalent, ...

  4. FINAL REPORT ON THE AQUATIC MERCURY ASSESSMENT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Halverson, N

    2008-09-30

    . Methylmercury ranged from 0.002 ng/l in Upper Three Runs to 2.60 ng/l in Tims Branch. Total mercury in the Savannah River ranged from 0.62 ng/l to 43.9 ng/l, and methylmercury ranged from 0.036 ng/l to 7.54 ng/l. Both total and methylmercury concentrations were consistently high in the river near the mouth of Steel Creek. Total mercury was positively correlated with methylmercury (r = 0.88). Total mercury bound to particulates ranged from 41% to 57% in the river and from 28% to 90% in the streams. Particulate methylmercury varied from 9% to 37% in the river and from 6% to 79% in the streams. Small temporary pools in the Savannah River swamp area near and around Fourmile Branch had the highest concentrations observed in the Savannah River watershed, reaching 1,890 ng/l for total mercury and 34.0 ng/l for methylmercury. The second study developed a mercury bioaccumulation factor (BAF) for the Savannah River near SRS. A BAF is the ratio of the concentration of mercury in fish flesh to the concentration of mercury in the water. BAFs are important in the TMDL process because target concentrations for mercury in water are computed from BAFs. Mercury BAFs are known to differ substantially among fish species, water bodies, and possibly seasons. Knowledge of such variation is needed to determine a BAF that accurately represents average and extreme conditions in the water body under study. Analysis of fish tissue and aqueous methylmercury samples collected at a number of locations and over several seasons in a 110 km (68 mile) reach of the Savannah River demonstrated that BAFs for each species under study varied by factors of three to eight. Influences on BAF variability were location, habitat and season-related differences in fish mercury levels and seasonal differences in methylmercury levels in the water. Overall (all locations, habitats, and seasons) average BAFs were 3.7 x 10{sup 6} for largemouth bass, 1.4 x 10{sup 6} for sunfishes, and 2.5 x 10{sup 6} for white catfish. This study

  5. Mercury Exposure and Heart Diseases.

    Science.gov (United States)

    Genchi, Giuseppe; Sinicropi, Maria Stefania; Carocci, Alessia; Lauria, Graziantonio; Catalano, Alessia

    2017-01-12

    Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive, and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease, and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence has shown that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system.

  6. Mercury Exposure and Heart Diseases

    Directory of Open Access Journals (Sweden)

    Giuseppe Genchi

    2017-01-01

    Full Text Available Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive, and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease, and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence has shown that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system.

  7. A survey of the mercury levels in the fish of the Federal Capital ...

    African Journals Online (AJOL)

    The mercury content of the freshwater fish of the Federal Capital Territory of Nigeria was determined. The mean Hg content in the fish was 215 + 57 (80 - 350) ng g-1 wet weight. Generally the levels of mercury in the samples were low with over 78% of the samples recording a total Hg level of less than 200 ng g-1 wet weight ...

  8. Mercury's exosphere: observations during MESSENGER's First Mercury flyby.

    Science.gov (United States)

    McClintock, William E; Bradley, E Todd; Vervack, Ronald J; Killen, Rosemary M; Sprague, Ann L; Izenberg, Noam R; Solomon, Sean C

    2008-07-04

    During MESSENGER's first Mercury flyby, the Mercury Atmospheric and Surface Composition Spectrometer measured Mercury's exospheric emissions, including those from the antisunward sodium tail, calcium and sodium close to the planet, and hydrogen at high altitudes on the dayside. Spatial variations indicate that multiple source and loss processes generate and maintain the exosphere. Energetic processes connected to the solar wind and magnetospheric interaction with the planet likely played an important role in determining the distributions of exospheric species during the flyby.

  9. Micro pit formation by mercury-sphere collision

    International Nuclear Information System (INIS)

    Ishikura, Syuichi; Kogawa, Hiroyuki; Futakawa, Masatoshi; Kaminaga, Masanori; Hino, Ryutaro

    2004-01-01

    The development of a MW-class spallation neutron source facility is being carried out under the Japan Proton Accelerator Research Complex (J-PARC) Project promoted by JAERI and KEK. A mercury target working as the spallation neutron source will be subjected to pressure waves generated by rapid thermal expansion of mercury due to a pulsed proton beam injection. The pressure wave will impose dynamic stress on the vessel and deform the vessel, which would cause cavitation in mercury. To evaluate the effect of mercury micro jets, driven by cavitation bubble collapse, on the micro-pit formation, analyses on mercury sphere collision were carried out: single bubble dynamics and collision behavior on interface between liquid and solid, which take the nonlinearity due to shock wave in mercury and the strain rate dependency of yield stress in solid metal into account. Analytical results give a good explanation to understand relationship between the micro-pit formation and material properties: the pit size could decrease with increasing the yield strength of materials. (author)

  10. Recovery of mercury from acid waste residues

    Science.gov (United States)

    Greenhalgh, Wilbur O.

    1989-12-05

    Mercury can be recovered from nitric acid-containing fluids by reacting the fluid with aluminum metal to produce mercury metal, and then quenching the reactivity of the nitric acid prior to nitration of the mercury metal.

  11. Mercury Poisoning Linked to Skin Products

    Science.gov (United States)

    ... Products For Consumers Home For Consumers Consumer Updates Mercury Poisoning Linked to Skin Products Share Tweet Linkedin ... and, in some situations, criminal prosecution. Dangers of Mercury Exposure to mercury can have serious health consequences. ...

  12. Bromination of petroleum coke for elemental mercury capture.

    Science.gov (United States)

    Xiao, Yi; Pudasainee, Deepak; Gupta, Rajender; Xu, Zhenghe; Diao, Yongfa

    2017-08-15

    Activated carbon injection has been proven to be an effective control technology of mercury emission from coal-fired power plants. Petroleum coke is a waste by-product of petroleum refining with large quantities readily available around the world. Due to its high inherent sulfur content, petroleum coke is an attractive raw material for developing mercury capture sorbent, converting a waste material to a value-added product of important environmental applications. In this study, petroleum coke was brominated by chemical-mechanical bromination. The brominated petroleum coke was characterized for thermal stability, mercury capture capacity, and potential mercury and bromine leaching hazards. Bromine loaded on the petroleum coke was found to be stable up to 200°C. Even after treating the brominated petroleum coke for 30min at 600°C, 1/3 bromine remained on the solid. The sorbent from bromination of sulfur-containing petroleum coke was shown to be a promising alternative to commercial brominated activated carbon for capture of elemental mercury from coal combustion flue gases. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Fly Ash and Mercury Oxidation/Chlorination Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Sukh Sidhu; Patanjali Varanasi

    2008-12-31

    a diffusion tube as the source of Hg0(g). All experiments were conducted using 4% O2 in nitrogen mix as a reaction gas, and other reactants (HCl, H2O and SO2, NO2, Br2) were added as required. The fixed bed reactor was operated over a temperature range of 200 to 400 C. In each experiment, the reactor effluent was analyzed using the modified Ontario-Hydro method. After each experiment, fly ash particles were also analyzed for mercury. The results show that the ability of fly ash to adsorb and/or oxidize mercury is primarily dependent on its carbon, iron and calcium content. There can be either one or more than one key component at a particular temperature and flue gas condition. Surface area played a secondary role in effecting the mercury transformations when compared to the concentration of the key component in the fly ash. Amount of carbon and surface area played a key important role in the adsorption of mercury. Increased concentration of gases in the flue gas other than oxygen and nitrogen caused decreased the amount of mercury adsorbed on carbon surface. Mercury adsorption by iron oxide primarily depended on the crystalline structure of iron oxide. {alpha}-Iron oxide had no effect on mercury adsorption or oxidation under most of the flue gas conditions, but ?-iron oxide adsorbed mercury under most of the flue gas conditions. Bromine is a very good oxidizing agent for mercury. But in the presence of calcium oxide containing fly ashes, all the oxidized mercury would be reduced to elemental form. Among the catalysts, it was observed that presence of free lattice chlorine in the catalyst was very important for the oxidation of mercury. But instead of using the catalyst alone, using it along with carbon may better serve the purpose by providing the adsorption surface for mercury and also some extra surface area for the reaction to occur (especially for fly ashes with low surface area).

  14. Evaluation of mercury cycling and hypolimnetic oxygenation in mercury-impacted seasonally stratified reservoirs in the Guadalupe River watershed, California

    Science.gov (United States)

    McCord, Stephen A.; Beutel, Marc W.; Dent, Stephen R.; Schladow, S. G.

    2016-10-01

    Surface water reservoirs trap inorganic mercury delivered from their watersheds, create conditions that convert inorganic mercury to highly toxic methylmercury (MeHg), and host sportfish in which MeHg bioaccumulates. The Santa Clara Valley Water District (District) actively manages and monitors four mercury-impaired reservoirs that help to serve communities in South San Francisco Bay, California. The Guadalupe River watershed, which contains three of those reservoirs, also includes the New Almaden mercury-mining district, the largest historic mercury producer in North America. Monthly vertical profiles of field measurements and grab samples in years 2011-2013 portray annual cycling of density stratification, dissolved oxygen (DO), and MeHg. Monitoring results highlight the role that hypolimnetic hypoxia plays in MeHg distribution in the water column, as well as the consistent, tight coupling between MeHg in ecological compartments (water, zooplankton, and bass) across the four reservoirs. Following the 2011-2013 monitoring period, the District designed and installed hypolimnetic oxygenation systems (HOS) in the four reservoirs in an effort to repress MeHg buildup in bottom waters and attain regulatory targets for MeHg in water and fish tissue. Initial HOS operation in Calero Reservoir in 2014 enhanced bottom water DO and depressed hypolimnetic buildup of MeHg, but did not substantially decrease mercury levels in zooplankton or small fish.

  15. SULFUR POLYMER STABILIZATION/SOLIDIFICATION (SPSS) TREATABILITY OF LOS ALAMOS NATIONAL LABORATORY MERCURY WASTE

    International Nuclear Information System (INIS)

    ADAMS, J.W.; KALB, P.D.

    2001-01-01

    Brookhaven National Laboratory's Sulfur Polymer Stabilization/Solidification (SPSS) process was used to treat approximately 90kg of elemental mercury mixed waste from Los Alamos National Laboratory. Treatment was carried out in a series of eight batches using a 1 ft(sup 3) pilot-scale mixer, where mercury loading in each batch was 33.3 weight percent. Although leach performance is currently not regulated for amalgamated elemental mercury (Hg) mixed waste, Toxicity Characteristic Leach Procedure (TCLP) testing of SPSS treated elemental mercury waste indicates that leachability is readily reduced to below the TCLP limit of 200 ppb (regulatory requirement following treatment by retort for wastes containingandgt; 260 ppb Hg), and with process optimization, to levels less than the stringent Universal Treatment Standard (UTS) limit of 25 ppb that is applied to waste containingandlt; 260 ppm Hg. In addition, mercury-contaminated debris, consisting of primary glass and plastic containers, as well as assorted mercury thermometers, switches, and labware, was first reacted with SPSS components to stabilize the mercury contamination, then macroencapsulated in the molten SPSS product. This treatment was done by vigorous agitation of the sulfur polymer powder and the comminuted debris. Larger plastic and metal containers were reacted to stabilize internal mercury contamination, and then filled with molten sulfur polymer to encapsulate the treated product

  16. SULFUR POLYMER STABILIZATION/SOLIDIFICATION (SPSS) TREATABILITY OF LOS ALAMOS NATIONAL LABORATORY MERCURY WASTE.

    Energy Technology Data Exchange (ETDEWEB)

    ADAMS,J.W.; KALB,P.D.

    2001-11-01

    Brookhaven National Laboratory's Sulfur Polymer Stabilization/Solidification (SPSS) process was used to treat approximately 90kg of elemental mercury mixed waste from Los Alamos National Laboratory. Treatment was carried out in a series of eight batches using a 1 ft{sup 3} pilot-scale mixer, where mercury loading in each batch was 33.3 weight percent. Although leach performance is currently not regulated for amalgamated elemental mercury (Hg) mixed waste, Toxicity Characteristic Leach Procedure (TCLP) testing of SPSS treated elemental mercury waste indicates that leachability is readily reduced to below the TCLP limit of 200 ppb (regulatory requirement following treatment by retort for wastes containing > 260 ppb Hg), and with process optimization, to levels less than the stringent Universal Treatment Standard (UTS) limit of 25 ppb that is applied to waste containing < 260 ppm Hg. In addition, mercury-contaminated debris, consisting of primary glass and plastic containers, as well as assorted mercury thermometers, switches, and labware, was first reacted with SPSS components to stabilize the mercury contamination, then macroencapsulated in the molten SPSS product. This treatment was done by vigorous agitation of the sulfur polymer powder and the comminuted debris. Larger plastic and metal containers were reacted to stabilize internal mercury contamination, and then filled with molten sulfur polymer to encapsulate the treated product.

  17. Role of bacteria in bioaccumulation of mercury in the oyster Crassostrea virginica

    International Nuclear Information System (INIS)

    Sayler, G.S.; Nelson, J.D. Jr.; Colwell, R.R.

    1975-01-01

    An investigation of mercury-resistant bacteria was undertaken to determine their role in the accumulation of mercury in a simplified food chain. Oysters (Crassostrea virginica) were maintained in a closed system, sealed aquarium with stirred, aerated water containing 10 μg of 203 HgCl 2 per liter. Uptake of 203 Hg by oysters held under control conditions was compared with that of 203 Hg uptake by oysters under similar conditions except that mercury-accumulating and mercury-metabolizing species of Pseudomonsa, isolated from Chesapeake Bay, were added to the experimental oysters. After incubation for 4 days, the major portion of the 203 Hg in the water column was found to be associated with the microparticulate fraction, corresponding to a rise in total viable count. Mercury accumulation in the oysters was significantly higher in the gill and fisceral tissue than other tissues. Mercury concentrations were 200 times greater in tissue fractions of oysters dosed with mercury-metabolizing bacteria compared with the oysters held under control conditions without mercury-metabolizing bacteria. (U.S.)

  18. Mercury, Vaccines, and Autism

    Science.gov (United States)

    Baker, Jeffrey P.

    2008-01-01

    The controversy regarding the once widely used mercury-containing preservative thimerosal in childhood vaccines has raised many historical questions that have not been adequately explored. Why was this preservative incorporated in the first place? Was there any real evidence that it caused harm? And how did thimerosal become linked in the public mind to the “autism epidemic”? I examine the origins of the thimerosal controversy and their legacy for the debate that has followed. More specifically, I explore the parallel histories of three factors that converged to create the crisis: vaccine preservatives, mercury poisoning, and autism. An understanding of this history provides important lessons for physicians and policymakers seeking to preserve the public’s trust in the nation’s vaccine system. PMID:18172138

  19. Mercury in Canadian crude oil

    International Nuclear Information System (INIS)

    Hollebone, B.P.

    2005-01-01

    Estimates for average mercury concentrations in crude oil range widely from 10 ng/g of oil to 3,500 ng/g of oil. With such a broad range of estimates, it is difficult to determine the contributions of the petroleum sector to the total budget of mercury emissions. In response to concerns that the combustion of petroleum products may be a major source of air-borne mercury pollution, Environment Canada and the Canadian Petroleum Products Institute has undertaken a survey of the average total mercury concentration in crude oil processed in Canadian refineries. In order to calculate the potential upper limit of total mercury in all refined products, samples of more than 30 different types of crude oil collected from refineries were measured for their concentration of mercury as it enters into a refinery before processing. High temperature combustion, cold vapour atomic absorption and cold vapour atomic fluorescence were the techniques used to quantify mercury in the samples. The results of the study provide information on the total mass of mercury present in crude oil processed in Canada each year. Results can be used to determine the impact of vehicle exhaust emissions to the overall Canadian mercury emission budget. 17 refs., 2 tabs., 2 figs

  20. Method for mercury refinement

    Science.gov (United States)

    Grossman, M.W.; Speer, R.; George, W.A.

    1991-04-09

    The effluent from mercury collected during the photochemical separation of the [sup 196]Hg isotope is often contaminated with particulate mercurous chloride, Hg[sub 2]Cl[sub 2]. The use of mechanical filtering via thin glass tubes, ultrasonic rinsing with acetone (dimethyl ketone) and a specially designed cold trap have been found effective in removing the particulate (i.e., solid) Hg[sub 2]Cl[sub 2] contaminant. The present invention is particularly directed to such filtering. 5 figures.

  1. Apparatus for mercury refinement

    Science.gov (United States)

    Grossman, M.W.; Speer, R.; George, W.A.

    1991-07-16

    The effluent from mercury collected during the photochemical separation of the [sup 196]Hg isotope is often contaminated with particulate mercurous chloride, Hg[sub 2]Cl[sub 2]. The use of mechanical filtering via thin glass tubes, ultrasonic rinsing with acetone (dimethyl ketone) and a specially designed cold trap have been found effective in removing the particulate (i.e., solid) Hg[sub 2]Cl[sub 2] contaminant. The present invention is particularly directed to such filtering. 5 figures.

  2. Apparatus for mercury refinement

    International Nuclear Information System (INIS)

    Grossman, M.W.; Speer, R.; George, W.A.

    1991-01-01

    The effluent from mercury collected during the photochemical separation of the 196 Hg isotope is often contaminated with particulate mercurous chloride, Hg 2 Cl 2 . The use of mechanical filtering via thin glass tubes, ultrasonic rinsing with acetone (dimethyl ketone) and a specially designed cold trap have been found effective in removing the particulate (i.e., solid) Hg 2 Cl 2 contaminant. The present invention is particularly directed to such filtering. 5 figures

  3. Method for scavenging mercury

    Science.gov (United States)

    Chang, Shih-ger [El Cerrito, CA; Liu, Shou-heng [Kaohsiung, TW; Liu, Zhao-rong [Beijing, CN; Yan, Naiqiang [Berkeley, CA

    2009-01-20

    Disclosed herein is a method for removing mercury from a gas stream comprising contacting the gas stream with a getter composition comprising bromine, bromochloride, sulphur bromide, sulphur dichloride or sulphur monochloride and mixtures thereof. In one preferred embodiment the getter composition is adsorbed onto a sorbent. The sorbent may be selected from the group consisting of flyash, limestone, lime, calcium sulphate, calcium sulfite, activated carbon, charcoal, silicate, alumina and mixtures thereof. Preferred is flyash, activated carbon and silica.

  4. Magnetic field of Mercury

    International Nuclear Information System (INIS)

    Jackson, D.J.; Beard, D.B.

    1977-01-01

    The geomagnetic field, suitably scaled down and parameterized, is shown to give a very good fit to the magnetic field measurements taken on the first and third passes of the Mariner 10 space probe past Mercury. The excellence of the fit to a reliable planetary magnetospheric model is good evidence that the Mercury magnetosphere is formed by a simple, permanent, intrinsic planetary magnetic field distorted by the effects of the solar wind. The parameters used for a best fit to all the data are (depending slightly on the choice of data) 2.44--2.55 for the ratio of Mercury's magnetic field strength at the subsolar point to that of the earth's subsolar point field (this results in a dipole moment of 170 γR/sub M/ 3 (R/sub M/ is Mercury Radius), i.e., 2.41 x 10 22 G cm 3 in the same direction as the earth's dipole), approx.-113 γR/sub M/ 4 for the planetary quadrupole moment parallel to the dipole moment, 10degree--17degree for the tilt of the planet dipole toward the sun, 4.5degree for the tilt of the dipole toward dawn, and 2.5degree--7.6degree aberration angle for the shift in the tail axis from the planet-sun direction because of the planet's orbital velocity. The rms deviation overall for the entire data set compared with the theoretical fitted model for the magnetic field strength was 17 γ (approx.4% of the maximum field measured). If the data from the first pass that show presumed strong time variations are excluded, the overall rms deviation for the field magnitude is only 10 γ

  5. The planet Mercury (1971)

    Science.gov (United States)

    1972-01-01

    The physical properties of the planet Mercury, its surface, and atmosphere are presented for space vehicle design criteria. The mass, dimensions, mean density, and orbital and rotational motions are described. The gravity field, magnetic field, electromagnetic radiation, and charged particles in the planet's orbit are discussed. Atmospheric pressure, temperature, and composition data are given along with the surface composition, soil mechanical properties, and topography, and the surface electromagnetic and temperature properties.

  6. Ultralow Level Mercury Treatment Using Chemical Reduction and Air Stripping: Scoping Report

    International Nuclear Information System (INIS)

    Looney, B.B.

    2000-01-01

    Data collected during the first stage of a Savannah River Technology Center (SRTC) Strategic Research and Development Project confirmed the efficacy of chemical reduction and air stripping/sparging as an ultralow level mercury treatment concept for waters containing Hg(II). The process consists of dosing the water with low levels of stannous chloride to convert the mercury to Hg. This form of mercury can easily be removed from the water by air stripping or sparging. Samples of Savannah River Site (SRS) groundwater containing approximately 130 ng/L of total mercury (as Hg(II)) were used for the study. In undosed samples, sparging removed 0 percent of the initial mercury. In the dosed samples, all of the removals were greater than 94 percent, except in one water type at one dose. This sample, which was saturated with dissolved oxygen, showed a 63 percent reduction in mercury following treatment at the lowest dose. Following dosing at minimally effective levels and sparging, treated water contained less than 10 ng/L total mercury. In general, the data indicate that the reduction of mercury is highly favored and that stannous chloride reagent efficiently targets the Hg(II) contaminant in the presence of competing reactions. Based on the results, the authors estimated that the costs of implementing and operating an ultralow level mercury treatment process based on chemical reduction and stripping/sparging are 10 percent to 20 percent of traditional treatment technologies

  7. Low-Cost Options for Moderate Levels of Mercury Control

    Energy Technology Data Exchange (ETDEWEB)

    Sharon Sjostrom

    2006-03-31

    On March 15, 2005, EPA issued the Clean Air Mercury Rule, requiring phased-in reductions of mercury emissions from electric power generators. ADA-ES, Inc., with support from DOE/NETL and industry partners, is conducting evaluations of EPRI's TOXECON II{trademark} process and of high-temperature reagents and sorbents to determine the capabilities of sorbent/reagent injection, including activated carbon, for mercury control on different coals and air emissions control equipment configurations. DOE/NETL targets for total mercury removal are {ge}55% (lignite), {ge}65% (subbituminous), and {ge}80% (bituminous). Based on work done to date at various scales, meeting the removal targets appears feasible. However, work needs to progress to more thoroughly document and test these promising technologies at full scale. This is the final site report for tests conducted at MidAmerican's Louisa Station, one of three sites evaluated in this DOE/NETL program. The other two sites in the program are MidAmerican's Council Bluff Station and Entergy's Independence Station. MidAmerican's Louisa Station burns Powder River Basin (PRB) coal and employs hot-side electrostatic precipitators with flue gas conditioning for particulate control. This part of the testing program evaluated the effect of reagents used in the existing flue gas conditioning on mercury removal.

  8. Mercury removal sorbents

    Science.gov (United States)

    Alptekin, Gokhan

    2016-03-29

    Sorbents and methods of using them for removing mercury from flue gases over a wide range of temperatures are disclosed. Sorbent materials of this invention comprise oxy- or hydroxyl-halogen (chlorides and bromides) of manganese, copper and calcium as the active phase for Hg.sup.0 oxidation, and are dispersed on a high surface porous supports. In addition to the powder activated carbons (PACs), this support material can be comprised of commercial ceramic supports such as silica (SiO.sub.2), alumina (Al.sub.2O.sub.3), zeolites and clays. The support material may also comprise of oxides of various metals such as iron, manganese, and calcium. The non-carbon sorbents of the invention can be easily injected into the flue gas and recovered in the Particulate Control Device (PCD) along with the fly ash without altering the properties of the by-product fly ash enabling its use as a cement additive. Sorbent materials of this invention effectively remove both elemental and oxidized forms of mercury from flue gases and can be used at elevated temperatures. The sorbent combines an oxidation catalyst and a sorbent in the same particle to both oxidize the mercury and then immobilize it.

  9. Mercury's Interior from MESSENGER Radio Science Data

    Science.gov (United States)

    Genova, A.; Mazarico, E.; Goossens, S. J.; Lemoine, F. G.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2017-12-01

    The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft provided precise radio tracking data in orbit about Mercury for more than 4 years, from March 2011 to April 2015. These geodetic measurements enable us to investigate the interior structure of the planet from the inner core to the crust. The first three years of radio data allowed us to determine the gravity field of Mercury with a resolution of 150 km in the northern hemisphere (degree and order 50 in spherical harmonics) since the periapsis was located at higher latitudes (>65˚N) and 200-500 km altitudes. The comparison of this gravity solution with Mercury's topography, which was retrieved by using over 25 million individual measurements of the Mercury Laser Altimeter (MLA), resulted in a preliminary map of the crustal thickness of the planet. However, those results were limited by the resolution of the gravity field since the topography was defined in spherical harmonics up to degree and order 125. The last year of the MESSENGER extended mission was dedicated to a low-altitude campaign, where the spacecraft periapsis was maintained at altitudes between 25 and 100 km. The radio data collected during this mission phase allowed us to significantly improve the resolution of the gravity field locally in the northern hemisphere up to degree and order 100 in spherical harmonics. We present the gravity anomalies and crustal thickness maps that lead to a better understanding on the formation and evolution of specific regions. We present our estimated orientation model, which slightly differs from the solutions that were obtained by using Earth-based radar measurements and the co-registration of MESSENGER imaging and altimetry data. These previous estimates provide a direct measurement of the surface response, whereas the orientation model from gravity is more sensitive to the inner and outer core. A discrepancy between core and surface obliquities may provide fundamental

  10. Binary mixtures of mercury/ selenium, and lead/selenium

    African Journals Online (AJOL)

    Physiologically-based biokinetic models have been developed for predicting simultaneously the Absorption, Distribution, Metabolism and Elimination (ADME) properties of lead (Pb) and selenium (Se), and mercury (Hg) and selenium in a number of target tissues of humans. This was done for three population groups, ...

  11. Spallation Neutron Source Accelerator Facility Target Safety and Non-safety Control Systems

    International Nuclear Information System (INIS)

    Battle, Ronald E.; DeVan, B.; Munro, John K. Jr.

    2006-01-01

    The Spallation Neutron Source (SNS) is a proton accelerator facility that generates neutrons for scientific researchers by spallation of neutrons from a mercury target. The SNS became operational on April 28, 2006, with first beam on target at approximately 200 W. The SNS accelerator, target, and conventional facilities controls are integrated by standardized hardware and software throughout the facility and were designed and fabricated to SNS conventions to ensure compatibility of systems with Experimental Physics Integrated Control System (EPICS). ControlLogix Programmable Logic Controllers (PLCs) interface to instruments and actuators, and EPICS performs the high-level integration of the PLCs such that all operator control can be accomplished from the Central Control room using EPICS graphical screens that pass process variables to and from the PLCs. Three active safety systems were designed to industry standards ISA S84.01 and IEEE 603 to meet the desired reliability for these safety systems. The safety systems protect facility workers and the environment from mercury vapor, mercury radiation, and proton beam radiation. The facility operators operated many of the systems prior to beam on target and developed the operating procedures. The safety and non-safety control systems were tested extensively prior to beam on target. This testing was crucial to identify wiring and software errors and failed components, the result of which was few problems during operation with beam on target. The SNS has continued beam on target since April to increase beam power, check out the scientific instruments, and continue testing the operation of facility subsystems

  12. Mercury flow tests (first report). Wall friction factor measurement tests and future tests plan

    International Nuclear Information System (INIS)

    Kaminaga, Masanori; Kinoshita, Hidetaka; Haga, Katsuhiro; Hino, Ryutaro; Sudo, Yukio

    1999-07-01

    In the neutron science project at JAERI, we plan to inject a pulsed proton beam of a maximum power of 5 MW from a high intense proton accelerator into a mercury target in order to produce high energy neutrons of a magnitude of ten times or more than existing facilities. The neutrons produced by the facility will be utilized for advanced field of science such as the life sciences etc. An urgent issue in order to accomplish this project is the establishment of mercury target technology. With this in mind, a mercury experimental loop with the capacity to circulate mercury up to 15 L/min was constructed to perform thermal hydraulic tests, component tests and erosion characteristic tests. A measurement of the wall friction factor was carried out as a first step of the mercury flow tests, while testing the characteristic of components installed in the mercury loop. This report presents an outline of the mercury loop and experimental results of the wall friction factor measurement. From the wall friction factor measurement, it was made clear that the wettability of the mercury was improved with an increase of the loop operation time and at the same time the wall friction factors were increased. The measured wall friction factors were much lower than the values calculated by the Blasius equation at the beginning of the loop operation because of wall slip caused by a non-wetted condition. They agreed well with the values calculated by the Blasius equation within a deviation of 10% when the sum of the operation time increased more than 11 hours. This report also introduces technical problems with a mercury circulation and future tests plan indispensable for the development of the mercury target. (author)

  13. Mercury Specie and Multi-Pollutant Control

    Energy Technology Data Exchange (ETDEWEB)

    Rob James; Virgil Joffrion; John McDermott; Steve Piche

    2010-05-31

    This project was awarded to demonstrate the ability to affect and optimize mercury speciation and multi-pollutant control using non-intrusive advanced sensor and optimization technologies. The intent was to demonstrate plant-wide optimization systems on a large coal fired steam electric power plant in order to minimize emissions, including mercury (Hg), while maximizing efficiency and maintaining saleable byproducts. Advanced solutions utilizing state-of-the-art sensors and neural network-based optimization and control technologies were proposed to maximize the removal of mercury vapor from the boiler flue gas thereby resulting in lower uncontrolled releases of mercury into the atmosphere. Budget Period 1 (Phase I) - Included the installation of sensors, software system design and establishment of the as-found baseline operating metrics for pre-project and post-project data comparison. Budget Period 2 (Phase II) - Software was installed, data communications links from the sensors were verified, and modifications required to integrate the software system to the DCS were performed. Budget Period 3 (Phase III) - Included the validation and demonstration of all control systems and software, and the comparison of the optimized test results with the targets established for the project site. This report represents the final technical report for the project, covering the entire award period and representing the final results compared to project goals. NeuCo shouldered 61% of the total project cost; while DOE shouldered the remaining 39%. The DOE requires repayment of its investment. This repayment will result from commercial sales of the products developed under the project. NRG's Limestone power plant (formerly owned by Texas Genco) contributed the host site, human resources, and engineering support to ensure the project's success.

  14. Mercury: Exploration of a Planet

    Science.gov (United States)

    1976-01-01

    The flight of the Mariner 10 spacecraft to Venus and Mercury is detailed in animation and photography. Views of Mercury are featured. Also included is animation on the origin of the solar system. Dr. Bruce C. Murray, director of the Jet Propulsion Laboratory, comments on the mission.

  15. Rotation of the planet mercury.

    Science.gov (United States)

    Jefferys, W H

    1966-04-08

    The equations of motion for the rotation of Mercury are solved for the general case by an asymptotic expansion. The findings of Liu and O'Keefe, obtained by numerical integration of a special case, that it is possible for Mercury's rotation to be locked into a 2:3 resonance with its revolution, are confirmed in detail. The general solution has further applications.

  16. 49 CFR 173.164 - Mercury (metallic and articles containing mercury).

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Mercury (metallic and articles containing mercury... Than Class 1 and Class 7 § 173.164 Mercury (metallic and articles containing mercury). (a) For transportation by aircraft, mercury must be packaged in packagings which meet the requirements of part 178 of...

  17. Mercury emissions from South Africa’s coal-fired power stations

    Directory of Open Access Journals (Sweden)

    Belinda L. Garnham

    2016-12-01

    can be achieved as a co-benefit of installing other emission abatement technologies. At the very least, more accurate calculations of mercury emissions per power station should be obtained by measuring the mercury content of more recent coal samples, and developing power station-specific ERF’s before mercury emission regulations are established or an investment into targeted mercury emission reduction technology is made.

  18. Experimental determination of cavitation thresholds in liquid water and mercury

    International Nuclear Information System (INIS)

    Taleyarkhan, R.P.; West, C.D.; Moraga, F.

    1998-01-01

    An overview is provided on cavitation threshold measurement experiments for water and mercury. Various aspects to be considered that affect onset determination are discussed along with design specifications developed for construction of appropriate apparatus types. Both static and transient-cavitation effects were studied using radically different apparatus designs. Preliminary data are presented for cavitation thresholds for water and mercury over a range of temperatures in static and high-frequency environments. Implications and issues related to spallation neutron source target designs and operation are discussed

  19. Source tracing of natural organic matter bound mercury in boreal forest runoff with mercury stable isotopes.

    Science.gov (United States)

    Jiskra, Martin; Wiederhold, Jan G; Skyllberg, Ulf; Kronberg, Rose-Marie; Kretzschmar, Ruben

    2017-10-18

    Terrestrial runoff represents a major source of mercury (Hg) to aquatic ecosystems. In boreal forest catchments, such as the one in northern Sweden studied here, mercury bound to natural organic matter (NOM) represents a large fraction of mercury in the runoff. We present a method to measure Hg stable isotope signatures of colloidal Hg, mainly complexed by high molecular weight or colloidal natural organic matter (NOM) in natural waters based on pre-enrichment by ultrafiltration, followed by freeze-drying and combustion. We report that Hg associated with high molecular weight NOM in the boreal forest runoff has very similar Hg isotope signatures as compared to the organic soil horizons of the catchment area. The mass-independent fractionation (MIF) signatures (Δ 199 Hg and Δ 200 Hg) measured in soils and runoff were in agreement with typical values reported for atmospheric gaseous elemental mercury (Hg 0 ) and distinctly different from reported Hg isotope signatures in precipitation. We therefore suggest that most Hg in the boreal terrestrial ecosystem originated from the deposition of Hg 0 through foliar uptake rather than precipitation. Using a mixing model we calculated the contribution of soil horizons to the Hg in the runoff. At moderate to high flow runoff conditions, that prevailed during sampling, the uppermost part of the organic horizon (Oe/He) contributed 50-70% of the Hg in the runoff, while the underlying more humified organic Oa/Ha and the mineral soil horizons displayed a lower mobility of Hg. The good agreement of the Hg isotope results with other source tracing approaches using radiocarbon signatures and Hg : C ratios provides additional support for the strong coupling between Hg and NOM. The exploratory results from this study illustrate the potential of Hg stable isotopes to trace the source of Hg from atmospheric deposition through the terrestrial ecosystem to soil runoff, and provide a basis for more in-depth studies investigating the

  20. Mercury concentration in bivalve molluscs

    Directory of Open Access Journals (Sweden)

    Szkoda Józef

    2015-09-01

    Full Text Available A total of 85 mussel samples of eight species were examined. Analysis of mercury in the freeze-dried samples was carried out by atomic absorption spectrometry method using direct mercury analyser AMA 254. The analytical procedure for determination of mercury was covered by the quality assurance programme of research and participation in national and international proficiency tests. Concentrations of total mercury in all investigated samples were found to be generally low, in the range of 0.033-0.577 mg/kg of dry weight and of 0.003-0.045 mg/kg of wet weight. The results indicate that obtained levels of mercury in bivalve molluscs are not likely to pose a risk to the health of consumers.

  1. Mercury: Beethoven Quadrangle, H-7

    Science.gov (United States)

    2000-01-01

    Mercury: Computer Photomosaic of the Beethoven Quadrangle, H-7 The Beethoven Quadrangle, named for the 19th century classical German composer, lies in Mercury's Equatorial Mercator located between longitude 740 to 1440. The Mariner 10 spacecraft imaged the region during its initial flyby of the planet. The Image Processing Lab at NASA's Jet Propulsion Laboratory produced this photomosaic using computer software and techniques developed for use in processing planetary data. The images used to construct the Beethoven Quadrangle were taken as Mariner 10 flew passed Mercury. The Mariner 10 spacecraft was launched in 1974. The spacecraft took images of Venus in February 1974 on the way to three encounters with Mercury in March and September 1974 and March 1975. The spacecraft took more than 7,000 images of Mercury, Venus, the Earth and the Moon during its mission. The Mariner 10 Mission was managed by the Jet Propulsion Laboratory for NASA's Office of Space Science in Washington, D.C.

  2. Human Exposure and Health Effects of Inorganic and Elemental Mercury

    OpenAIRE

    Park, Jung-Duck; Zheng, Wei

    2012-01-01

    Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability o...

  3. Methods for dispensing mercury into devices

    Science.gov (United States)

    Grossman, Mark W.; George, William A.

    1987-04-28

    A process for dispensing mercury into devices which requires mercury. Mercury is first electrolytically separated from either HgO or Hg.sub.2 Cl.sub.2 and plated onto a cathode wire. The cathode wire is then placed into a device requiring mercury.

  4. 21 CFR 872.3700 - Dental mercury.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental mercury. 872.3700 Section 872.3700 Food and... DENTAL DEVICES Prosthetic Devices § 872.3700 Dental mercury. (a) Identification. Dental mercury is a device composed of mercury intended for use as a component of amalgam alloy in the restoration of a...

  5. Recent Approaches to Modeling Transport of Mercury in Surface Water and Groundwater - Case Study in Upper East Fork Poplar Creek, Oak Ridge, TN - 13349

    International Nuclear Information System (INIS)

    Bostick, Kent; Daniel, Anamary; Tachiev, Georgio; Malek-Mohammadi, Siamak

    2013-01-01

    below a target industrial groundwater concentration beneath the source and would not influence concentrations in surface water at Station 17. This analysis addressed only shallow concentrations in soil and the shallow groundwater flow path in soil and unconsolidated sediments to UEFPC. Other mercury sources may occur in bedrock and transport though bedrock to UEFPC may contribute to the mercury flux at Station 17. Generally mercury in the source areas adjacent to the stream and in sediment that is eroding can contribute to the flux of mercury in surface water. Because colloidally adsorbed mercury can be transported in surface water, actions that trap colloids and or hydrologically isolate surface water runoff from source areas would reduce the flux of mercury in surface water. Mercury in soil is highly adsorbed and transport in the groundwater system is very limited under porous media conditions. (authors)

  6. Fluorescent sensor for mercury

    Science.gov (United States)

    Wang, Zidong [Urbana, IL; Lee, Jung Heon [Evanston, IL; Lu, Yi [Champaign, IL

    2011-11-22

    The present invention provides a sensor for detecting mercury, comprising: a first polynucleotide, comprising a first region, and a second region, a second polynucleotide, a third polynucleotide, a fluorophore, and a quencher, wherein the third polynucleotide is optionally linked to the second region; the fluorophore is linked to the first polynucleotide and the quencher is linked to the second polynucleotide, or the fluorophore is linked to the second polynucleotide and the quencher is linked to the first polynucleotide; the first region and the second region hybridize to the second polynucleotide; and the second region binds to the third polynucleotide in the presence of Hg.sup.2+ ions.

  7. Increased mercury emissions from modern dental amalgams

    OpenAIRE

    Bengtsson, Ulf G.; Hylander, Lars D.

    2017-01-01

    All types of dental amalgams contain mercury, which partly is emitted as mercury vapor. All types of dental amalgams corrode after being placed in the oral cavity. Modern high copper amalgams exhibit two new traits of increased instability. Firstly, when subjected to wear/polishing, droplets rich in mercury are formed on the surface, showing that mercury is not being strongly bonded to the base or alloy metals. Secondly, high copper amalgams emit substantially larger amounts of mercury vapor ...

  8. Catch tanks inhibitor addition 200-East and 200-West Areas

    International Nuclear Information System (INIS)

    Palit, A.N.

    1996-01-01

    Reported is the study of 11 catch tanks in the 200-East Area and the 7 catch tanks in the 200-West Area listed as active. The location, capacity, material of construction, annual total accumulation, annual rain intrusion, waste transfer rate, and access for chemical injection in these tanks are documented. The present and future utilization and isolation plans for the catch tanks are established

  9. Mercury kinetics in marine zooplankton

    International Nuclear Information System (INIS)

    Fowler, S.W.; Heyraud, M.; LaRosa, J.

    1976-01-01

    Mercury, like many other heavy metals, is potentially available to marine animals by uptake directly from water and/or through the organisms food. Furthermore, bioavailability, assimilation and subsequent retention in biota may be affected by the chemical species of the element in sea water. While mercury is known to exist in the inorganic form in sea water, recent work has indicated that, in certain coastal areas, a good portion of the total mercury appears to be organically bound; however, the exact chemical nature of the organic fraction has yet to be determined. Methyl mercury may be one constituent of the natural organically bound fraction since microbial mechanisms for in situ methylation of mercury have been demonstrated in the aquatic environment. Despite the fact that naturally produced methyl mercury probably comprises only a small fraction of an aquatic ecosystem, the well-documented toxic effects of this organo-mercurial, caused by man-made introductions into marine food chains, make it an important compound to study

  10. Atmospheric mercury footprints of nations.

    Science.gov (United States)

    Liang, Sai; Wang, Yafei; Cinnirella, Sergio; Pirrone, Nicola

    2015-03-17

    The Minamata Convention was established to protect humans and the natural environment from the adverse effects of mercury emissions. A cogent assessment of mercury emissions is required to help implement the Minamata Convention. Here, we use an environmentally extended multi-regional input-output model to calculate atmospheric mercury footprints of nations based on upstream production (meaning direct emissions from the production activities of a nation), downstream production (meaning both direct and indirect emissions caused by the production activities of a nation), and consumption (meaning both direct and indirect emissions caused by final consumption of goods and services in a nation). Results show that nations function differently within global supply chains. Developed nations usually have larger consumption-based emissions than up- and downstream production-based emissions. India, South Korea, and Taiwan have larger downstream production-based emissions than their upstream production- and consumption-based emissions. Developed nations (e.g., United States, Japan, and Germany) are in part responsible for mercury emissions of developing nations (e.g., China, India, and Indonesia). Our findings indicate that global mercury abatement should focus on multiple stages of global supply chains. We propose three initiatives for global mercury abatement, comprising the establishment of mercury control technologies of upstream producers, productivity improvement of downstream producers, and behavior optimization of final consumers.

  11. One-millipound mercury ion thruster

    Science.gov (United States)

    Hyman, J., Jr.; Dulgeroff, C. R.; Kami, S.; Williamson, W. S.

    1975-01-01

    A mercury ion thruster has been developed for efficient operation at the nominal 1-mlb thrust level with a specific impulse of about 3,000 sec and a total power consumption of about 120 W. At a beam voltage of 1,200 V and beam current of 72 mA, the discharge chamber operates with a propellant efficiency of 93.8% at an ion-generation energy of 276 eV/ion. The 8-cm diameter thruster advances proven component technology to assure the capability for thruster operation over an accumulated beam-on time in excess of 20,000 hours with a capability for 10,000 on-off duty cycles. Discharge chamber optimization has combined stable current-voltage characteristics with high performance efficiency by careful placement of the discharge cathode near the location of a magnetic-field zero just upstream of the thruster endplate.

  12. Method for removal and stabilization of mercury in mercury-containing gas streams

    Science.gov (United States)

    Broderick, Thomas E.

    2005-09-13

    The present invention is directed to a process and apparatus for removing and stabilizing mercury from mercury-containing gas streams. A gas stream containing vapor phase elemental and/or speciated mercury is contacted with reagent, such as an oxygen-containing oxidant, in a liquid environment to form a mercury-containing precipitate. The mercury-containing precipitate is kept or placed in solution and reacts with one or more additional reagents to form a solid, stable mercury-containing compound.

  13. Estimation of mercury emissions into the Slovene environment in 2001

    Directory of Open Access Journals (Sweden)

    Martina Svetina

    2002-12-01

    Full Text Available The aim of the study was to collect data for better control of mercury emissions in Slovenia, especially from the point and spread sources of all categories. In the past years the Slovenian industry avoided the use of mercury as a raw material in the productionprocess to prevent the emissions and discharge of this hazardous substance. About 733 kg of Hg was imported with products, 620 kg Hg was produced with coal combustion and cement production, 920 kg was sold with products and around 200 kg was exported as waste in year 2001. Annually 1620 kg of Hg emission into environment is estimated, of this approximately 900 kg is deposited as waste, 630 kg escape in the air and 90 kg in water. The following sectors have been identified in Slovenia as the potential sources of mercury into environment: the thermal power plants, dental amalgams, products of electric industry (batteries, lamps, thermometers, manometers, barometers, chemicals, cement industry, incineration and waste treatment. A mercury flow diagram for Slovenia in theyear 2001 was established.

  14. Exploring Mercury: The Iron Planet

    OpenAIRE

    Stevenson, David J.

    2004-01-01

    Planet Mercury is both difficult to observe and difficult to reach by spacecraft. Just one spacecraft, Mariner 10, flew by the planet 30 years ago. An upcoming NASA mission, MESSENGER, will be launched this year and will go into orbit around Mercury at the end of this decade. A European mission is planned for the following decade. It's worth going there because Mercury is a strange body and the history of planetary exploration has taught us that strangeness gives us insight into planetary ori...

  15. MESSENGER'S First Flyby of Mercury

    Science.gov (United States)

    Slavin, James A.

    2008-01-01

    The MESSENGER mission to Mercury offers our first opportunity to explore this planet's miniature magnetosphere since Mariner 10's brief fly-bys in 1974-5. The magnetosphere of Mercury is the smallest in the solar system with its magnetic field typically standing off the solar wind only - 1000 to 2000 km above the surface. An overview of the MESSENGER mission and its January 14th close flyby of Mercury will be provided. Primary science objectives and the science instrumentation will be described. Initial results from MESSENGER'S first flyby on January 14th, 2008 will be discussed with an emphasis on the magnetic field and charged particle measurements.

  16. Vaporization of elemental mercury from pools of molten lead at low concentrations

    International Nuclear Information System (INIS)

    Greene, G.A.; Finfrock, C.C.

    2000-01-01

    Should coolant accidentally be lost to the APT (Accelerator Production of Tritium) blanket and target, and the decay heat in the target be deposited in the surrounding blanket by thermal radiation, temperatures in the blanket modules could exceed structural limits and cause a physical collapse of the blanket modules into a non-coolable geometry. Such a sequence of unmitigated events could result in some melting of the APT blanket and create the potential for the release of mercury into the target-blanket cavity air space. Experiments were conducted which simulate such hypothetical accident conditions in order to measure the rate of vaporization of elemental mercury from pools of molten lead to quantify the possible severe accident source term for the APT blanket region. Molten pools of from 0.01% to 0.10% mercury in lead were prepared under inert conditions. Experiments were conducted, which varied in duration from several hours to as long as a month, to measure the mercury vaporization from the lead pools. The melt pools and gas atmospheres were held fixed at 340 C during the tests. Parameters which were varied in the tests included the mercury concentration, gas flow rate over the melt and agitation of the melt, gas atmosphere composition and the addition of aluminum to the melt. The vaporization of mercury was found to scale roughly linearly with the concentration of mercury in the pool. Variations in the gas flow rates were not found to have any effect on the mass transfer, however agitation of the melt by a submerged stirrer did enhance the mercury vaporization rate. The rate of mercury vaporization with an argon (inert) atmosphere was found to exceed that for an air (oxidizing) atmosphere by as much as a factor of from ten to 20; the causal factor in this variation was the formation of an oxide layer over the melt pool with the air atmosphere which served to retard mass transfer across the melt-atmosphere interface. Aluminum was introduced into the melt to

  17. ICP OES and CV AAS in determination of mercury in an unusual fatal case of long-term exposure to elemental mercury in a teenager.

    Science.gov (United States)

    Lech, Teresa

    2014-04-01

    In this work, a case of deliberate self-poisoning is presented. A 14-year-old girl suddenly died during one of the several hospitalizations. Abdominal computer tomography showed a large number of metallic particles in the large intestine. Analysis of blood and internal organs for mercury and other toxic metals carried out by inductively coupled plasma optical emission spectrometry (ICP OES) revealed high concentrations of mercury in kidneys and liver (64,200 and 2470ng/g, respectively), less in stomach (90ng/g), and none in blood. Using cold vapor-atomic absorption spectrometry (CV AAS), high levels of mercury were confirmed in all examined materials, including blood (87ng/g), and additionally in hair. The results of analysis obtained by two techniques revealed that the exposure to mercury was considerable (some time later, it was stated that the mercury originated from thermometers that had been broken over the course of about 1 year, because of Münchausen syndrome). CV AAS is a more sensitive technique, particularly for blood samples (negative results using ICP OES), and tissue samples - with LOQ: 0.63ng/g of Hg (CV AAS) vis-à-vis 70ng/g of Hg (ICP OES). However, ICP OES may be used as a screening technique for autopsy material in acute poisoning by a heavy metal, even one as volatile as mercury. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. Distribution and retention of organic and inorganic mercury in methyl mercury-treated neonatal rats

    International Nuclear Information System (INIS)

    Thomas, D.J.; Fisher, H.L.; Sumler, M.R.; Hall, L.L.; Mushak, P.

    1988-01-01

    Seven-day-old Long Evans rats received one mumol of 203 Hg-labeled methyl mercury/kg sc and whole body retention and tissue distribution of organic and inorganic mercury were examined for 32 days postdosing. Neonates cleared mercury slowly until 10 days postdosing when the clearance rate abruptly increased. During the interval when whole body clearance of mercury was extremely slow, methyl mercury was metabolized to inorganic mercury. Peak concentration of mercury in kidney occurred at 2 days postdosing. At 32 days postdosing, 8% of mercury in kidney was in an organic from. Liver mercury concentration peaked at 2 days postdosing and organic mercury accounted for 38% at 32 days postdosing. Brain concentrations of mercury peaked at 2 days postdosing. At 10 days postdosing, organic mercury accounted for 86% of the brain mercury burden, and, at 32 days postdosing, for 60%. The percentage of mercury body burden in pelt rose from 30 to 70% between 1 and 10 days postdosing. At 32 days postdosing pelt contained 85% of the body burden of mercury. At all time points, about 95% of mercury in pelt was in an organic form. Compartmental analysis of these data permitted development of a model to describe the distribution and excretion of organic and inorganic mercury in methyl mercury-treated neonatal rats

  19. 34 CFR 200.84 - Responsibilities of SEAs for evaluating the effectiveness of the MEP.

    Science.gov (United States)

    2010-07-01

    ... ACADEMIC ACHIEVEMENT OF THE DISADVANTAGED Migrant Education Program § 200.84 Responsibilities of SEAs for...'s performance targets in § 200.83(a)(1), particularly for those students who have priority for...

  20. Disposal strategy of proton irradiated mercury from high power spallation sources

    International Nuclear Information System (INIS)

    Chiriki, Suresh

    2010-01-01

    Large spallation sources are intended to be constructed in Europe (EURISOL: nuclear physics research facility and ESS: European Spallation Source). These facilities would accumulate more than 20 metric tons of irradiated mercury in the target, which has to be treated as highly radioactive and chemo-toxic waste. Liquid waste cannot be tolerated in European repositories. As part of this work on safety/decommissioning of high-power spallation sources, our investigations were focused mainly to study experimentally and theoretically the solidification of liquid mercury waste (selection of an adequate solid mercury form and of an immobilization matrix, chemical engineering process studies on solidification/stabilization and on encapsulating in a matrix). Based on experimental results and supported by literature Hg-chalcogens (HgS, HgSe) will be more stable in repositories than amalgams. Our irradiation experimental studies on mercury waste revealed that mercury sulfide is a reasonable solid for disposal and shows larger stability in possible accidents with water ingress in a repository. Additionally immobilization of mercury in a cement matrix and polysiloxane matrix were tested. HgS formation from liquid target mercury by a wet process is identified as a suitable formation procedure. These investigations reveal that an almost 99.9% elementary Hg conversion can be achieved and that wet process can be reasonably handled under hot cell conditions. (orig.)

  1. Disposal strategy of proton irradiated mercury from high power spallation sources

    Energy Technology Data Exchange (ETDEWEB)

    Chiriki, Suresh

    2010-07-01

    Large spallation sources are intended to be constructed in Europe (EURISOL: nuclear physics research facility and ESS: European Spallation Source). These facilities would accumulate more than 20 metric tons of irradiated mercury in the target, which has to be treated as highly radioactive and chemo-toxic waste. Liquid waste cannot be tolerated in European repositories. As part of this work on safety/decommissioning of high-power spallation sources, our investigations were focused mainly to study experimentally and theoretically the solidification of liquid mercury waste (selection of an adequate solid mercury form and of an immobilization matrix, chemical engineering process studies on solidification/stabilization and on encapsulating in a matrix). Based on experimental results and supported by literature Hg-chalcogens (HgS, HgSe) will be more stable in repositories than amalgams. Our irradiation experimental studies on mercury waste revealed that mercury sulfide is a reasonable solid for disposal and shows larger stability in possible accidents with water ingress in a repository. Additionally immobilization of mercury in a cement matrix and polysiloxane matrix were tested. HgS formation from liquid target mercury by a wet process is identified as a suitable formation procedure. These investigations reveal that an almost 99.9% elementary Hg conversion can be achieved and that wet process can be reasonably handled under hot cell conditions. (orig.)

  2. Mercury and Selenium in Muscle and Target Organs of Scalloped Hammerhead Sharks Sphyrna lewini of the SE Gulf of California: Dietary Intake, Molar Ratios, Loads, and Human Health Risks.

    Science.gov (United States)

    Bergés-Tiznado, Magdalena E; Márquez-Farías, Fernando; Lara-Mendoza, Raúl E; Torres-Rojas, Yassir E; Galván-Magaña, Felipe; Bojórquez-Leyva, Humberto; Páez-Osuna, Federico

    2015-11-01

    Selenium and mercury were evaluated in muscle, liver, kidney, brain, and the stomach contents of juvenile scalloped hammerhead shark Sphyrna lewini. Se:Hg molar ratios were calculated. The average Hg levels in muscle ranged from 0.12 to 1.17 μg/g (wet weight); Hg was 1. Correlations were found for Hg in muscle with size, age, and weight, and also for Hg in liver with size, age, and weight. Hg in muscle was significantly positive correlated to Hg in brain as well as Hg in liver was correlated to Hg in kidney. The highest Hg in preys was for carangid fishes; scombrid and carangid fishes contributed with the highest Se levels. Results suggest that more than 98 % of the total Hg and 62 % of Se end up in muscle and might be affected by factors, such as geographical area, age, size, and feeding habits. The muscle of S. lewini should be consumed by people cautiously so as not to exceed the recommended intake per week.

  3. Elimination of mercury in health care facilities.

    Science.gov (United States)

    2000-03-01

    Mercury is a persistent, bioaccumulative toxin that has been linked to numerous health effects in humans and wildlife. It is a potent neurotoxin that may also harm the brain, kidneys, and lungs. Unborn children and young infants are at particular risk for brain damage from mercury exposure. Hospitals' use of mercury in chemical solutions, thermometers, blood pressure gauges, batteries, and fluorescent lamps makes these facilities large contributors to the overall emission of mercury into the environment. Most hospitals recognize the dangers of mercury. In a recent survey, four out of five hospitals stated that they have policies in place to eliminate the use of mercury-containing products. Sixty-two percent of them require vendors to disclose the presence of mercury in chemicals that the hospitals purchase. Only 12 percent distribute mercury-containing thermometers to new parents. Ninety-two percent teach their employees about the health and environmental effects of mercury, and 46 percent teach all employees how to clean up mercury spills. However, the same study showed that many hospitals have not implemented their policies. Forty-two percent were not aware whether they still purchased items containing mercury. In addition, 49 percent still purchase mercury thermometers, 44 percent purchase mercury gastrointestinal diagnostic equipment, and 64 percent still purchase mercury lab thermometers.

  4. Mercury pollution: a transdisciplinary treatment

    National Research Council Canada - National Science Library

    Zuber, Sharon L; Newman, Michael C

    2012-01-01

    .... Also included are smaller case studies, such as the Minamata tragedy, fish consumption, and international treaties"-- "Mercury is the gravest chemical pollutant problem of our time, and this is...

  5. Origin and composition of Mercury

    International Nuclear Information System (INIS)

    Lewis, J.S.

    1988-01-01

    The predictions of the expected range of composition of Mercury at the time of its formation made on the basis of a suite of condensation-accretion models of Mercury spanning a range of condensation temperature and accretion sampling functions appropriate to Mercury are examined. It is concluded that these compositonal models can, if modified to take into account the nonselective loss of most of the silicate component of the planet during accretion, provide compositional predictions for the Weidenschilling (1978, 1980) mechanism for the accretion of a metal-rich Mercury. The silicate portion would, in this case, contain 3.6 to 4.5 percent alumina, roughly 1 percent of alkali oxides, and between 0.5 and 6 percent FeO

  6. Mercury bioremediation by mercury resistance transposon-mediated in situ molecular breeding.

    Science.gov (United States)

    Matsui, Kazuaki; Endo, Ginro

    2018-04-01

    Mercury-resistant (Hg R ) bacteria occur in various bacterial species from a wide variety of environmental sources. Resistance is conferred by a set of operon genes termed the mer operon. Many Hg R bacteria have been isolated from diverse environments and clinical samples, and it is recognized that mer operons are often localized on transposons. Previous research reports have suggested that Hg R transposons participate in the horizontal gene transfer of mer operons among bacteria. This was confirmed by a study that found that mer operons were distributed worldwide in Bacilli with dissemination of TnMERI1-like transposons. In this mini review, possible strategies for transposon-mediated in situ molecular breeding (ISMoB) of Hg R bacteria in their natural habitat are discussed. In ISMoB, the target microorganisms for breeding are indigenous bacteria that are not Hg R but that are dominant and robust in their respective environments. Additionally, we propose a new concept of bioremediation technology for environmental mercury pollution by applying transposon-mediated ISMoB for environmental mercury pollution control.

  7. Localized surface plasmon resonance mercury detection system and methods

    Science.gov (United States)

    James, Jay; Lucas, Donald; Crosby, Jeffrey Scott; Koshland, Catherine P.

    2016-03-22

    A mercury detection system that includes a flow cell having a mercury sensor, a light source and a light detector is provided. The mercury sensor includes a transparent substrate and a submonolayer of mercury absorbing nanoparticles, e.g., gold nanoparticles, on a surface of the substrate. Methods of determining whether mercury is present in a sample using the mercury sensors are also provided. The subject mercury detection systems and methods find use in a variety of different applications, including mercury detecting applications.

  8. Scientific objectives and instrumentation of Mercury Plasma Particle Experiment (MPPE) onboard MMO

    Czech Academy of Sciences Publication Activity Database

    Saito, Y.; Sauvaud, J. A.; Hirahara, M.; Němeček, Z.; Trávníček, Pavel M.; BepiColombo, MMO/MPPE team.

    2010-01-01

    Roč. 58, 1-2 (2010), s. 182-200 ISSN 0032-0633 Institutional research plan: CEZ:AV0Z30420517 Keywords : Mercury * Magnetosphere * Instrumentation * Plasma * Charged particles Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.344, year: 2010 http://www.sciencedirect.com/science/article/pii/S0032063308001529

  9. Mercury Toolset for Spatiotemporal Metadata

    Science.gov (United States)

    Devarakonda, Ranjeet; Palanisamy, Giri; Green, James; Wilson, Bruce; Rhyne, B. Timothy; Lindsley, Chris

    2010-06-01

    Mercury (http://mercury.ornl.gov) is a set of tools for federated harvesting, searching, and retrieving metadata, particularly spatiotemporal metadata. Version 3.0 of the Mercury toolset provides orders of magnitude improvements in search speed, support for additional metadata formats, integration with Google Maps for spatial queries, facetted type search, support for RSS (Really Simple Syndication) delivery of search results, and enhanced customization to meet the needs of the multiple projects that use Mercury. It provides a single portal to very quickly search for data and information contained in disparate data management systems, each of which may use different metadata formats. Mercury harvests metadata and key data from contributing project servers distributed around the world and builds a centralized index. The search interfaces then allow the users to perform a variety of fielded, spatial, and temporal searches across these metadata sources. This centralized repository of metadata with distributed data sources provides extremely fast search results to the user, while allowing data providers to advertise the availability of their data and maintain complete control and ownership of that data. Mercury periodically (typically daily)harvests metadata sources through a collection of interfaces and re-indexes these metadata to provide extremely rapid search capabilities, even over collections with tens of millions of metadata records. A number of both graphical and application interfaces have been constructed within Mercury, to enable both human users and other computer programs to perform queries. Mercury was also designed to support multiple different projects, so that the particular fields that can be queried and used with search filters are easy to configure for each different project.

  10. Mercury Toolset for Spatiotemporal Metadata

    Science.gov (United States)

    Wilson, Bruce E.; Palanisamy, Giri; Devarakonda, Ranjeet; Rhyne, B. Timothy; Lindsley, Chris; Green, James

    2010-01-01

    Mercury (http://mercury.ornl.gov) is a set of tools for federated harvesting, searching, and retrieving metadata, particularly spatiotemporal metadata. Version 3.0 of the Mercury toolset provides orders of magnitude improvements in search speed, support for additional metadata formats, integration with Google Maps for spatial queries, facetted type search, support for RSS (Really Simple Syndication) delivery of search results, and enhanced customization to meet the needs of the multiple projects that use Mercury. It provides a single portal to very quickly search for data and information contained in disparate data management systems, each of which may use different metadata formats. Mercury harvests metadata and key data from contributing project servers distributed around the world and builds a centralized index. The search interfaces then allow the users to perform a variety of fielded, spatial, and temporal searches across these metadata sources. This centralized repository of metadata with distributed data sources provides extremely fast search results to the user, while allowing data providers to advertise the availability of their data and maintain complete control and ownership of that data. Mercury periodically (typically daily) harvests metadata sources through a collection of interfaces and re-indexes these metadata to provide extremely rapid search capabilities, even over collections with tens of millions of metadata records. A number of both graphical and application interfaces have been constructed within Mercury, to enable both human users and other computer programs to perform queries. Mercury was also designed to support multiple different projects, so that the particular fields that can be queried and used with search filters are easy to configure for each different project.

  11. Studies on the preparation of thallium-201 by irradiating mercury with protons using extraction chromatography technique to separate thallium from mercury

    International Nuclear Information System (INIS)

    Fernandes, L.

    1990-01-01

    Radionuclide sup(201)Tl is used in Nuclear Medicine to identify myocardial ischemia or myocardial infarct. It is a cyclotron-produced radioisotope, obtained indirectly from the decay of sup(202)Pb or directly by irradiating mercury with deuterons or protons. The usual technique to prepare sup(201)Tl makes use of the nuclear reaction: sup(203)(p,3n) → sup(201)Tl, which requires proton energy of around 28 MeV. Due to the limited proton energy of IPEN'S CV-28 cyclotron, studies on the irradiating conditions of natural mercury oxide pellets and drops of natural mercury metal were made in the range of 19 - 24 MeV. At the end of the bombardment of a 6 MeV thickness target of natural mercury metal with 19 MeV protons around 10 MBq sup(201)Tl/μ A h was obtained. (author)

  12. The Mercury Laser Advances Laser Technology for Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Ebbers, C A; Caird, J; Moses, E

    2009-01-21

    The National Ignition Facility (NIF) at Lawrence Livermore Laboratory is on target to demonstrate 'breakeven' - creating as much fusion-energy output as laser-energy input. NIF will compress a tiny sphere of hydrogen isotopes with 1.8 MJ of laser light in a 20-ns pulse, packing the isotopes so tightly that they fuse together, producing helium nuclei and releasing energy in the form of energetic particles. The achievement of breakeven will culminate an enormous effort by thousands of scientists and engineers, not only at Livermore but around the world, during the past several decades. But what about the day after NIF achieves breakeven? NIF is a world-class engineering research facility, but if laser fusion is ever to generate power for civilian consumption, the laser will have to deliver pulses nearly 100,000 times faster than NIF - a rate of perhaps 10 shots per second as opposed to NIF's several shots a day. The Mercury laser (named after the Roman messenger god) is intended to lead the way to a 10-shots-per-second, electrically-efficient, driver laser for commercial laser fusion. While the Mercury laser will generate only a small fraction of the peak power of NIF (1/30,000), Mercury operates at higher average power. The design of Mercury takes full advantage of the technology advances manifest in its behemoth cousin (Table 1). One significant difference is that, unlike the flashlamp-pumped NIF, Mercury is pumped by highly efficient laser diodes. Mercury is a prototype laser capable of scaling in aperture and energy to a NIF-like beamline, with greater electrical efficiency, while still running at a repetition rate 100,000 times greater.

  13. 200 GW for Germany; 200 Gigawatt fuer Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Fuhs, Michael; Enkhardt, Sandra

    2012-11-01

    200 GW of solar power, i.e. seven times as much as today: Is that a realistic goal, or is it just propaganda for a lobby intending to make a good life for manufacturers and fitters? There is much to suggest that it may be a socially relevant goal.

  14. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2005-06-01

    Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems. Our current strategy is to engineer plants to

  15. Autometallographic tracing of mercury in frog liver

    International Nuclear Information System (INIS)

    Loumbourdis, N.S.; Danscher, G.

    2004-01-01

    The distribution of mercury in the liver of the frog Rana ridibunda with the autometallographic method was investigated. The mercury specific autometallographic (HgS/Se AMG ) technique is a sensitive histochemical approach for tracing mercury in tissues from mercury-exposed organisms. Mercury accumulates in vivo as mercury sulphur/mercury selenium nanocrystals that can be silver-enhanced. Thus, only a fraction of the Hg can be visualized. Six animals were exposed for one day and another group of six animals for 6 days in 1 ppm mercury (as HgCI 2 ) dissolved in fresh water. A third group of six animals, served as controls, were sacrificed the day of arrival at the laboratory. First, mercury appears in the blood plasma and erythrocytes. Next, mercury moves to hepatocytes and in the apical part of the cells, that facing bile canaliculi. In a next step, mercury appears in the endothelial and Kupffer cells. It seems likely that, the mercury of hepatocytes moves through bile canaliculi to the gut, most probably bound to glutathione and/or other similar ligands. Most probably, the endothelial and Kupffer cells comprise the first line of defense against metal toxicity. - Frogs can be good bioindicators of mercury

  16. Mercury in the Carson and Truckee River basins of Nevada

    Science.gov (United States)

    Van Denburgh, A.S.

    1973-01-01

    Upstream from major pre-1900 ore milling in the Carson and Truckee River basins, "background" concentrations of total mercury in the upper 1 to 3 inches of sand- to clay-sized stream-bottom sediment are less than 0.1 ug/g (microgram per gram). Downstream, measured concentrations were as much as 200 times the background level. Greatest concentrations were encountered in the Carson River basin within and immediately upstream from Lahontan Reservoir. Data from for the Carson River near Fort Churchill suggest that most of the mercury in the sampled bottom sediment may be present as mercuric sulfide or as a component of one of more non-methyl organic compounds or complexes, rather than existing in the metallic state. Regardless of state, this reservoir of mercury is of concern because of its possible availability to the aquatic food chain and, ultimately, to man. Among 48 samples of surface water from 29 sites in the two basins, the maximum measured total-mercury concentration was 6.3 ug/1 (micrograms per liter), for a sample from the Carson River near Fort Churchill. Except downstream from Lahontan Reservoir, most other measured values were less than 1 ug/1. (The U.S> Environmental Protection Agency interim limit for drinking water is 5 ug/1.) The total-mercury content of stream water is related to the mercury content of bottom sediments and the rate of streamflow, because the latter affects the suspended-sediment transporting capability of the stream,. Near Fort Churchill, total-mercury concentrations that might be expected at streamflows greater than those of 1971-72 are: as much as 10-15 ug/1 or more at 2,000 cfs (cubic feet per second), and as much as 10-20 ug/1 or more at 3,000 cfs. Elsewhere, expectable concentrations are much less because the bottom sediment contains much less mercury. The mercury contents of water samples from 36 wells in the Carson and Truckee basins were all less than 1 ug/1, indicating that mercury is not a problem in ground water, even

  17. Mercury: Aspects of its ecology and environmental toxicity. [physiological effects of mercury compound contamination of environment

    Science.gov (United States)

    Siegel, S. M.

    1973-01-01

    A study was conducted to determine the effects of mercury pollution on the environment. The possible sources of mercury contamination in sea water are identified. The effects of mercury on food sources, as represented by swordfish, are analyzed. The physiological effects of varying concentrations of mercury are reported. Emphasis is placed on the situation existing in the Hawaiian Islands.

  18. Groundwater Modeling Of Mercury Pollution At A Former Mercury Cell Chlor Alkali Facility In Pavoldar, Kazakhstan

    Science.gov (United States)

    In Kazakhstan, there is a serious case of mercury pollution near the city of Pavlodar from an old mercury cell chlor-alkali plant. The soil, sediment, and water is severly contaminated with mercury and mercury compounds as a result of the industrial activity of this chemical pla...

  19. Human exposure and risk assessment associated with mercury pollution in the Caqueta River, Colombian Amazon.

    Science.gov (United States)

    Olivero-Verbel, Jesus; Carranza-Lopez, Liliana; Caballero-Gallardo, Karina; Ripoll-Arboleda, Adriana; Muñoz-Sosa, Diego

    2016-10-01

    Mercury (Hg) is a global contaminant posing severe risks to human health worldwide. The aim of this study was to assess the levels of total Hg (T-Hg) in human hair and fish in the Caqueta River, at the Colombian Amazon, as well as to determine fish consumption-based risks for T-Hg ingestion. T-Hg levels were measured using a direct mercury analyzer. The overall mean T-Hg level in hair for humans in the Caqueta River sample (n = 200) was 17.29 ± 0.61 μg/g (1.2 to 47.0 μg/g). Ninety-four percent of the individuals had hair T-Hg concentrations greater than the WHO threshold level (5 μg/g), and 79 % displayed levels higher than 10 μg/g. Average Hg concentrations in fish varied between 0.10-0.15 μg/g and 0.10-1.60 μg/g, for noncarnivorous and carnivorous species, respectively. Based on the maximum allowable fish consumption rate for adults, most carnivorous species should be avoided in the diet, as their target hazard quotient ranged from 2.96 up to 31.05, representing a risk for Hg-related health problems. In the light of existing evidence for elevated Hg levels in the indigenous population of the Colombian Amazon, carnivorous fish should be restricted as part of the diet, and breastfeeding should be reduced to protect children health. Most importantly, gold mining activities directly on rivers demand immediate attention from the national government to avoid extensive damage on the environment and human health.

  20. Biogeochemical cycle of mercury species in the marine environment

    International Nuclear Information System (INIS)

    Branica, M.

    1987-10-01

    Mercury contamination of the coastal marine environment is an important concern as highly toxic methyl-mercury may be formed biogenically in sediments rich in organic matter. The present study was conducted using a highly sensitive adaptation of Cold Vapour Atomic Absorption Spectrophotometry (CVAAS) in which mercury was re-mineralised from a variety of marine matrices (water, sediments and organisms), separated and concentrated by ion-exchange chromatography, trapped as an amalgam in gold wool and subsequently re-released by heating to 900 deg. C. Total and organomercury forms were detected respectively by measuring, in the case of seawater, sample extracts treated and untreated with uv light and, in the case of solid matrices, by ''total digestion'' and 6M HCl extractions. Detection limits were 0.1 ng/1 from a 200 ml water sample and 0.2 μg/kg for a lg solid sample. Water, sediments and organisms were collected by scuba diving from the unpolluted Sibenik aquatorium (including the Krka river estuary), Yugoslavia, and the polluted Kastela Bay, which receives discharge from a chlor-alkali plant. Mercury levels were low in the Sibenik aquatorium (0.34-2.4 ng/dm 3 water, 78-1522 μg/kg sediments and 24-39 μg/kg w.w. in mussels). Organo-mercury was generally below detection limits in water and represented below 0.5% of the total Hg in sediments but 13-88% of the mercury in mussels and fish. In the Kastela Bay, up to 90 ng/dm 3 (water), 11870 μg/kg w.w. (mussels) and 48600 μg kg w.w. (oysters) of Hg was detected. Fortunately methyl-mercury was below 0.5% of this total in all matrices. Hg levels in mussels decreased to 41.3 μg/kg w.w. at 600 m from the source. Further research will now be conducted on the biogeochemical cycle of Hg in estuarine and marine environments, with special attention being paid to the fresh/saline water interface. 9 refs, 2 figs, 5 tabs

  1. Evaluation of Energy Consumption in the Mercury Treatment of Phosphor Powder from Spent Fluorescent Lamps Using a Thermal Process

    Directory of Open Access Journals (Sweden)

    Yong Choi

    2017-11-01

    Full Text Available In a pilot-plant-scale thermal mercury treatment of phosphor powder from spent fluorescent lamps, energy consumption was estimated to control mercury content by the consideration of reaction kinetics. Mercury content was analyzed as a function of treatment temperature and time. The initial mercury content of the phosphor powder used in the thermal process was approximately 3500 mg/kg. The target mercury content in the phosphor powder thermal process of the phosphor powder was 5 mg/kg or less at 400 °C or higher because the target mercury content was recommended by Minamata Convention and Basel Convention. During thermal processing, the reaction rate was represented by a first order reaction with the Arrhenius equation. The reaction rate constant increased with temperature from 0.0112 min−1 at 350 °C to 0.0558 min−1 at 600 °C. The frequency factor was 2.51 min−1, and the activation energy was 6509.11 kcal/kg. Reaction rate constants were used to evaluate the treatment time required to reduce mercury content in phosphor powder to be less than 5 mg/kg. The total energy consumption in a pilot-plant-scale thermal process was evaluated to determine the optimal temperature for removing mercury in phosphor powder.

  2. Sorption of mercury on chemically synthesized polyaniline

    International Nuclear Information System (INIS)

    Remya Devi, P.S.; Verma, R.; Sudersanan, M.

    2006-01-01

    Sorption of inorganic mercury (Hg 2+ ) and methyl mercury, on chemically synthesized polyaniline, in 0.1-10N HCl solutions has been studied. Hg 2+ is strongly sorbed at low acidities and the extent of sorption decreases with increase in acidity. The sorption of methyl mercury is very low in the HCl concentration range studied. Sorption of Hg 2+ on polyaniline in 0.1-10N LiCl and H 2 SO 4 solutions has also been studied. The analysis of the data indicates that the sorption of Hg 2+ depends on the degree of protonation of polyaniline and the nature of mercury(II) chloride complexes in solution. X-ray photoelectron spectroscopy analysis (XPS) of polyaniline sorbed with mercury show that mercury is bound as Hg 2+ . Sorbed mercury is quantitatively eluted from polyaniline with 0.5N HNO 3 . Polyaniline can be used for separation and pre-concentration of inorganic mercury from aqueous samples. (author)

  3. EPA Leadership in the Global Mercury Partnership

    Science.gov (United States)

    The Global Mercury Partnership is a voluntary multi-stakeholder partnership initiated in 2005 to take immediate actions to protect human health and the environment from the releases of mercury and its compounds to the environment.

  4. Mercury-Containing Devices and Demolition

    Science.gov (United States)

    Some items inside residential buildings contain mercury, which poses a persistent and toxic human health and environmental threat. These materials should be carefully salvaged for proper recycling to prevent mercury contamination prior to demolition.

  5. Health Effects of Exposures to Mercury

    Science.gov (United States)

    ... Mercury in Your Environment Contact Us Share Health Effects of Exposures to Mercury Related Health Information for ... About PDF ; discussion starts on page 20) Methylmercury Effects Effects on People of All Ages Exposure to ...

  6. The effect of longterm exposure to mercury on the bacterial community in marine sediment

    DEFF Research Database (Denmark)

    Rasmussen, Lasse Dam; Sørensen, Søren Johannes

    1998-01-01

    Mercury pollution, bacteria, diversity, mercury resistance, antibiotic resistance, plasmid abundance......Mercury pollution, bacteria, diversity, mercury resistance, antibiotic resistance, plasmid abundance...

  7. Method for the removal and recovery of mercury

    Science.gov (United States)

    Easterly, Clay E.; Vass, Arpad A.; Tyndall, Richard L.

    1997-01-01

    The present invention is an enhanced method for the removal and recovery of mercury from mercury-contaminated matrices. The method involves contacting a mercury-contaminated matrix with an aqueous dispersant solution derived from specific intra-amoebic isolates to release the mercury from the mercury-contaminated matrix and emulsify the mercury; then, contacting the matrix with an amalgamating metal from a metal source to amalgamate the mercury to the amalgamating metal; removing the metallic source from the mercury-contaminated matrix; and heating the metallic source to vaporize the mercury in a closed system to capture the mercury vapors.

  8. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2004-12-01

    Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems.

  9. Mercury Continuous Emmission Monitor Calibration

    Energy Technology Data Exchange (ETDEWEB)

    John Schabron; Eric Kalberer; Ryan Boysen; William Schuster; Joseph Rovani

    2009-03-12

    Mercury continuous emissions monitoring systems (CEMs) are being implemented in over 800 coal-fired power plant stacks throughput the U.S. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor calibrators/generators. These devices are used to calibrate mercury CEMs at power plant sites. The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005 and vacated by a Federal appeals court in early 2008 required that calibration be performed with NIST-traceable standards. Despite the vacature, mercury emissions regulations in the future will require NIST traceable calibration standards, and EPA does not want to interrupt the effort towards developing NIST traceability protocols. The traceability procedures will be defined by EPA. An initial draft traceability protocol was issued by EPA in May 2007 for comment. In August 2007, EPA issued a conceptual interim traceability protocol for elemental mercury calibrators. The protocol is based on the actual analysis of the output of each calibration unit at several concentration levels ranging initially from about 2-40 {micro}g/m{sup 3} elemental mercury, and in the future down to 0.2 {micro}g/m{sup 3}, and this analysis will be directly traceable to analyses by NIST. The EPA traceability protocol document is divided into two separate sections. The first deals with the qualification of calibrator models by the vendors for use in mercury CEM calibration. The second describes the procedure that the vendors must use to certify the calibrators that meet the qualification specifications. The NIST traceable certification is performance based, traceable to analysis using isotope dilution inductively coupled plasma

  10. Mercury detection with thermal neutrons

    International Nuclear Information System (INIS)

    Bell, Z.W.

    1994-01-01

    This report describes the work performed to design a gauge to detect mercury concealed within walls, floors, pipes, and equipment inside a building. The project arose out of a desire to decontaminate and decommission (D ampersand D) a building in which mercury had been used as part of a chemical process. The building contains plumbing and equipment, some with residual mercury even after draining, sumps, and hollow walls. So that releases of mercury to the environment might be minimized during D ampersand D activities, it was considered advisable to locate pockets of mercury that may have collected in concealed spaces so that they might be drained in a controlled fashion prior to the application of the wrecking ball or sledge hammer. The detection of such pockets within a building presents some problems not ordinarily encountered in a laboratory environment. Often, only a single side of a wall or pipe is accessible. This condition disqualifies transmission gauges (such as conventional x radiography) in which a probe is sent through the volume under test (VUT) from one side and its passage or attenuation is detected on the opposite side. A robust, one-sided system was needed

  11. Mercury bioaccumulation in the Mediterranean

    Directory of Open Access Journals (Sweden)

    Cinnirella S.

    2013-04-01

    Full Text Available This study details mercury pollution within the food chain of the Mediterranean by analysing the most comprehensive mercury dataset available for biota and water measurements. In this study we computed a bioaccumulation factor (BAF for datasets in the existing mercury-related scientific literature, in on-going programs, and in past measurement campaigns. Preliminary results indicate a major lack of information, making the outcome of any assessment very uncertain. Importantly, not all marine eco-regions are (or have ever been covered by measurement campaigns. Most lacking is information associated with the South-Eastern part of the Mediterranean, and in several eco-regions it is still impossible to reconstruct a trophic net, as the required species were not accounted for when mercury measurements were taken. The datasets also have additional temporal sampling problems, as species were often not sampled systematically (but only sporadically during any given sampling period. Moreover, datasets composed of mercury concentrations in water also suffer from similar geographic limitations, as they are concentrated in the North-Western Mediterranean. Despite these concerns, we found a very clear bioaccumulation trend in 1999, the only year where comprehensive information on both methylmercury concentrations in water and biota was available.

  12. Mineral resource of the month: mercury

    Science.gov (United States)

    ,

    2012-01-01

    The article offers information on mercury, a mineral commodity used in industrial and small-scale gold mining applications. Mercury has been reported to be used for amalgamation with gold since the Roman times. Mercury from cinnabar from Almadén, Spain has been used by Romans and has been continued to be used through the Middle Ages and the Colonial era.

  13. 40 CFR 721.10068 - Elemental mercury.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Elemental mercury. 721.10068 Section... Substances § 721.10068 Elemental mercury. (a) Definitions. The definitions in § 721.3 apply to this section... elemental mercury (CAS. No. 7439-97-6) is subject to reporting under this section for the significant new...

  14. Current and future levels of mercury atmospheric pollution on a global scale

    Science.gov (United States)

    Pacyna, Jozef M.; Travnikov, Oleg; De Simone, Francesco; Hedgecock, Ian M.; Sundseth, Kyrre; Pacyna, Elisabeth G.; Steenhuisen, Frits; Pirrone, Nicola; Munthe, John; Kindbom, Karin

    2016-10-01

    research instrument for supporting the scientific justification for the Minamata Convention and monitoring of the implementation of targets of this convention, as well as the EU Mercury Strategy. This project provided the state of the art with regard to the development of the latest emission inventories for mercury, future emission scenarios, dispersion modelling of atmospheric mercury on a global and regional scale, and source-receptor techniques for mercury emission apportionment on a global scale.

  15. Current and future levels of mercury atmospheric pollution on a global scale

    Directory of Open Access Journals (Sweden)

    J. M. Pacyna

    2016-10-01

    proved to be a very important research instrument for supporting the scientific justification for the Minamata Convention and monitoring of the implementation of targets of this convention, as well as the EU Mercury Strategy. This project provided the state of the art with regard to the development of the latest emission inventories for mercury, future emission scenarios, dispersion modelling of atmospheric mercury on a global and regional scale, and source–receptor techniques for mercury emission apportionment on a global scale.

  16. How Tiny Collisions Shape Mercury

    Science.gov (United States)

    Kohler, Susanna

    2017-07-01

    If space rocks are unpleasant to encounter, space dust isnt much better. Mercurys cratered surface tells of billions of years of meteoroid impacts but its thin atmosphere is what reveals its collisional history with smaller impactors. Now new research is providing a better understanding of what were seeing.Micrometeoroids Ho!The inner solar system is bombarded by micrometeoroids, tiny particles of dust (on the scale of a tenth of a millimeter) emitted by asteroids and comets as they make their closest approach to the Sun. This dust doesnt penetrateEarths layers of atmosphere, but the innermost planet of our solar system, Mercury, doesnt have this convenient cushioning.Just as Mercury is affected by the impacts of large meteoroids, its also shaped by the many smaller-scale impacts it experiences. These tiny collisions are thought to vaporize atoms and molecules from the planets surface, which quickly dissociate. This process adds metals to Mercurys exosphere, the planets extremely tenuous atmosphere.Modeling PopulationsDistribution of the directions from which meteoroids originate before impacting Mercurys surface, as averaged over its entire orbit. Local time of 12 hr corresponds to the Sun-facing side. A significant asymmetry is seen between the dawn (6 hrs) and dusk (18 hrs) rates. [Pokorn et al. 2017]The metal distribution in the exosphere provides a way for us to measure the effect of micrometeoroid impacts on Mercury but this only works if we have accurate models of the process. A team of scientists led by Petr Pokorn (The Catholic University of America and NASA Goddard SFC) has now worked to improve our picture of micrometeoroid impact vaporization on Mercury.Pokorn and collaborators argue that two meteoroid populations Jupiter-family comets (short-period) and Halley-type comets (long-period) contribute the dust for the majority of micrometeoroid impacts on Mercury. The authors model the dynamics and evolution of these two populations, reproducing the

  17. Control of mercury emissions: policies, technologies, and future trends

    OpenAIRE

    Rhee, Seung-Whee

    2015-01-01

    Seung-Whee Rhee Department of Environmental Engineering, Kyonggi University, Suwon, Republic of Korea Abstract: Owing to the Minamata Convention on Mercury and the Global Mercury Partnership, policies and regulations on mercury management in advanced countries were intensified by a mercury phaseout program in the mercury control strategy. In developing countries, the legislative or regulatory frameworks on mercury emissions are not established specifically, but mercury management is designed...

  18. Canadian mercury inventories: the missing pieces

    Energy Technology Data Exchange (ETDEWEB)

    Hagreen, L.A.; Lourie, B.A. [Summerhill Group, Toronto, ON (Canada)

    2004-07-01

    Research was conducted to determine the significance of the deliberate use of mercury in products in Canada and the associated releases from these sources. Through a combination of literature review and new calculations, the reservoir, flux, and releases of mercury from eight product sources were calculated, and these results compared to historical Canadian inventories. Mercury contributions from the waste sector were also assessed and compared to total Canadian mercury releases and to mercury releases from coal-fired generating stations. Results suggest the use and release of mercury associated with its use in products is 4.5 times what previous inventories indicate. Including dental amalgam and sewage sludge, the total releases of mercury to all environmental compartments in Canada totals 20 tonnes per year. This accounts for less than one-half of the 44 tonnes per year of mercury released from mercury waste disposal each year in Canada. Waste mercury contributions from hazardous waste imports, unknown product sources, and incomplete information on the use of mercury in known products may account for this discrepancy. Waste-related mercury releases and transfers for disposal and recycling are 11 times greater than that of electricity generation in Canada. Results indicate that Canadian inventories have underestimated the significance of mercury use and release associated with products, calling into question the current priorities for mercury management. This paper was developed as part of a panel session at the International Joint Commission 'Mercury in the Ecosystem' workshop, February 26-27, 2003, Windsor, ON, Canada, as a complement to the information on Canadian Inventories presented by Luke Trip (Senes Consulting, Ottawa, ON, Canada).

  19. EURISOL-DS Multi-MW Target: Cost Analysis for a Proposed Development Phase

    CERN Document Server

    Karel, Samec; Kadi, Yacine; Noah, Etam; Lettry, Jacques; Wagner, Werner; Thomsen, Knud; Patorski, Jacek; Dementevjs, Sergej; Zik, Anatoli; Platacis, Erik

    The EURISOL Design Study has reached final completion and the three institutes, CERN, IPUL and PSI, participating in the development of the Multi-Megawatt target station have met the objective of a reliable, affordable and credible design. The costs involved in the full development of such a target are forecast to reach 200 million €, approximately 15% of the total costs of the EURISOL facility.A breakdown of the costs is presented as well as an outline of future possible R&D efforts aimed at improving reliability and safety of the facility. Another important goal of the proposed R&D is to minimise development risk by focusing resources, early on in the project, on areas identified as presenting a particular risk. An example clearly identified in the study would be the conditioning of the contaminated Mercury, both during the lifetime of the facility and after decommissioning.

  20. Global Sources and Pathways of Mercury in the Context of Human Health

    Science.gov (United States)

    Sundseth, Kyrre; Pacyna, Jozef M.; Pacyna, Elisabeth G.; Pirrone, Nicola; Thorne, Rebecca J.

    2017-01-01

    This paper reviews information from the existing literature and the EU GMOS (Global Mercury Observation System) project to assess the current scientific knowledge on global mercury releases into the atmosphere, on global atmospheric transport and deposition, and on the linkage between environmental contamination and potential impacts on human health. The review concludes that assessment of global sources and pathways of mercury in the context of human health is important for being able to monitor the effects from implementation of the Minamata Convention targets, although new research is needed on the improvement of emission inventory data, the chemical and physical behaviour of mercury in the atmosphere, the improvement of monitoring network data, predictions of future emissions and speciation, and on the subsequent effects on the environment, human health, as well as the economic costs and benefits of reducing these aspects. PMID:28117743

  1. Global Sources and Pathways of Mercury in the Context of Human Health

    Directory of Open Access Journals (Sweden)

    Kyrre Sundseth

    2017-01-01

    Full Text Available This paper reviews information from the existing literature and the EU GMOS (Global Mercury Observation System project to assess the current scientific knowledge on global mercury releases into the atmosphere, on global atmospheric transport and deposition, and on the linkage between environmental contamination and potential impacts on human health. The review concludes that assessment of global sources and pathways of mercury in the context of human health is important for being able to monitor the effects from implementation of the Minamata Convention targets, although new research is needed on the improvement of emission inventory data, the chemical and physical behaviour of mercury in the atmosphere, the improvement of monitoring network data, predictions of future emissions and speciation, and on the subsequent effects on the environment, human health, as well as the economic costs and benefits of reducing these aspects.

  2. Sodium Velocity Maps on Mercury

    Science.gov (United States)

    Potter, A. E.; Killen, R. M.

    2011-01-01

    The objective of the current work was to measure two-dimensional maps of sodium velocities on the Mercury surface and examine the maps for evidence of sources or sinks of sodium on the surface. The McMath-Pierce Solar Telescope and the Stellar Spectrograph were used to measure Mercury spectra that were sampled at 7 milliAngstrom intervals. Observations were made each day during the period October 5-9, 2010. The dawn terminator was in view during that time. The velocity shift of the centroid of the Mercury emission line was measured relative to the solar sodium Fraunhofer line corrected for radial velocity of the Earth. The difference between the observed and calculated velocity shift was taken to be the velocity vector of the sodium relative to Earth. For each position of the spectrograph slit, a line of velocities across the planet was measured. Then, the spectrograph slit was stepped over the surface of Mercury at 1 arc second intervals. The position of Mercury was stabilized by an adaptive optics system. The collection of lines were assembled into an images of surface reflection, sodium emission intensities, and Earthward velocities over the surface of Mercury. The velocity map shows patches of higher velocity in the southern hemisphere, suggesting the existence of sodium sources there. The peak earthward velocity occurs in the equatorial region, and extends to the terminator. Since this was a dawn terminator, this might be an indication of dawn evaporation of sodium. Leblanc et al. (2008) have published a velocity map that is similar.

  3. Apparatus for control of mercury

    Science.gov (United States)

    Downs, William; Bailey, Ralph T.

    2001-01-01

    A method and apparatus for reducing mercury in industrial gases such as the flue gas produced by the combustion of fossil fuels such as coal adds hydrogen sulfide to the flue gas in or just before a scrubber of the industrial process which contains the wet scrubber. The method and apparatus of the present invention is applicable to installations employing either wet or dry scrubber flue gas desulfurization systems. The present invention uses kraft green liquor as a source for hydrogen sulfide and/or the injection of mineral acids into the green liquor to release vaporous hydrogen sulfide in order to form mercury sulfide solids.

  4. Decommissioning and safety issues of liquid-mercury waste generated from high power spallation sources with particle accelerators

    CERN Document Server

    Chiriki, S; Odoj, R; Moormann, R; Hinssen, H. K; Bukaemskiy, A

    2009-01-01

    Large spallation sources are intended to be constructed in Europe (EURISOL nuclear physics facility and ESS-European Spallation Source). These facilities accumulate more than 20 metric tons of irradiated mercury in the target, which has to be treated as highly radioactive and chemo-toxic waste. Because solids are the only appropriate (immobile) form for this radiotoxic and toxic type of waste solidification is required for irradiated mercury. Our irradiation experimental studies on mercury waste revealed that mercury sulfide is a reasonable solid for disposal and shows larger stability in assumed accidents with water ingress in a repository compared to amalgams. For preparation of mercury sulfide a wet process is more suitable than a dry one. It is easier to perform under hot cell conditions and allows complete Hg-conversion. Embedding HgS in a cementitious matrix increases its stability.

  5. Coal fired flue gas mercury emission controls

    CERN Document Server

    Wu, Jiang; Pan, Weiguo; Pan, Weiping

    2015-01-01

    Mercury (Hg) is one of the most toxic heavy metals, harmful to both the environment and human health. Hg is released into the atmosphere from natural and anthropogenic sources and its emission control has caused much concern. This book introduces readers to Hg pollution from natural and anthropogenic sources and systematically describes coal-fired flue gas mercury emission control in industry, especially from coal-fired power stations. Mercury emission control theory and experimental research are demonstrated, including how elemental mercury is oxidized into oxidized mercury and the effect of

  6. Marine biogeochemistry of mercury

    International Nuclear Information System (INIS)

    Gill, G.A.

    1986-01-01

    Noncontaminating sample collection and handling procedures and accurate and sensitive analysis methods were developed to measure sub-picomolar Hg concentrations in seawater. Reliable and diagnostic oceanographic Hg distributions were obtained, permitting major processes governing the marine biogeochemistry of Hg to be identified. Mercury concentrations in the northwest Atlantic, central Pacific, southeast Pacific, and Tasman Sea ranged from 0.5 to 12 pM. Vertical Hg distributions often exhibited a maximum within or near the main thermocline. At similar depths, Hg concentrations in the northwest Atlantic Ocean were elevated compared to the N. Pacific Ocean. This pattern appears to result from a combination of enhanced supply of Hg to the northwest Atlantic by rainfall and scavenging removal along deep water circulation pathways. These observations are supported by geochemical steady-state box modelling which predicts a relatively short mean residence time for Hg in the oceans; demonstrating the reactive nature of Hg in seawater and precluding significant involvement in nutrient-type recyclic. Evidence for the rapid removal of Hg from seawater was obtained at two locations. Surface seawater Hg measurements along 160 0 W (20 0 N to 20 0 S) showed a depression in the equatorial upwelling area which correlated well with the transect region exhibiting low 234 Th/ 238 U activity ratios. This relationship implies that Hg will be scavenged and removed from surface seawater in biologically productive oceanic zones. Further, a broad minimum in the vertical distribution of Hg was observed to coincide with the intense oxygen minimum zone in the water column in coastal waters off Peru

  7. Infrared spectroscopy of Mercury analogue materials under simulated Mercury surface temperature conditions

    Science.gov (United States)

    Reitze, Maximilian; Morlok, Andreas; Hiesinger, Harald; Weber, Iris; Stojic, Aleksandra

    2017-04-01

    Infrared spectroscopy is a powerful technique for the exploration of planetary surfaces with remote sensing observations [e.g., 1]. The MERTIS (Mercury Radiometer and Thermal Infrared Spectrometer) instrument onboard the BepiColombo spacecraft is designed to explore the surface mineralogy of Mercury in the wavelength region from 7 μ m to 14 μ m [2]. Mercury's surface reaches dayside temperatures of about 700 K [3]. It is well known that bondings between atoms change with temperature, resulting in infrared spectra changes with temperature [4]. In particular, rock-forming minerals like silicates show distinct absorption bands in the infrared due to molecular vibrations, for example, of Si-O bondings [4]. To accurately understand and correctly interpret returned MERTIS data, it is necessary to collect laboratory data of analogue materials under condition similar to Mercury [5]. It is known from previous investigations [5] that the Reststrahlenbands of olivine shift with temperature. In this work we report on temperature effects on Mercury analogue materials in ambient air. At the IRIS (Infrared & Raman for Interplanetary Spectroscopy) laboratory in Münster we used a Bruker VERTEX 70v IR spectrometer together with a Harrick heating stage in a Praying Mantis Diffuse Reflectance Accessory to measure mid-infrared reflectance of mineral powder samples with different grain sizes at increasing temperatures. We report on our spectral results for a natural olivine with Fo91 with a grain size range between 63 μ m and 125 μ m as well as a natural labradorite with a grain size range between 90 μ m and 125 μ m. Spectra were collected at 26, 75, 150, 200, 250, 300, and 350 degrees Celsius with a liquid nitrogen cooled MCT detector under normal ambient pressure. To ensure complete thermal equilibrium of our measured samples, we heated them to higher temperatures and subsequently cooled them to the temperatures at which the spectra were taken. For background calibration, we

  8. ISABELLE: a 200 + 200 GeV colliding beam facility

    International Nuclear Information System (INIS)

    Courant, E.D.

    1977-01-01

    Plans are under way for the construction of a pair of intersecting storage rings providing for colliding beams of protons of energy at least 200 GeV. The rings (circumference 2.62 km) will contain superconducting magnets constructed with braided Nb--Ti filamentary wire, with a peak field of 4.0 T corresponding to an energy of 200 GeV. A current of 10 A of protons will be injected at 29 GeV from the existing AGS accelerator at Brookhaven, using the energy stacking technique similar to that employed at the CERN ISR; subsequently the stored beam will be accelerated gradually in the storage rings. Six intersection areas will be provided for experiments. They are designed to provide flexibility in beam characteristics for different experiments. The maximum luminosity at full energy is expected to be 1.0 x 10 33 cm -2 s -1 , at 29 GeV it will be approximately 10 32 cm -2 s -1 . Recent work with prototype magnets indicates that fields of 5.0 T can be produced. This has led to an alternative design of somewhat larger rings (circumference 3.77 km) that should be capable of providing colliding beams at 400 + 400 GeV

  9. Line broadening in the neutral and ionized mercury spectra

    Science.gov (United States)

    Gavrilov, M.; Skočić, M.; Burger, M.; Bukvić, S.; Djeniže, S.

    2012-10-01

    The neutral, singly, doubly and triply ionized mercury (Hg I-IV, respectively) spectral line shapes and line center positions have been investigated in the laboratory helium plasma at electron densities ranging between 9.3 × 1022 m-3 and 1.93 × 1023 m-3 and electron temperatures around 19,500 K, both interesting for astrophysics. The mercury (natural isotope composition) atoms were sputtered from the cylindrical amalgamated gold plates located in the homogenous part of the pulsed helium discharge operating at a pressure of 665 Pa in a flowing regime. The mercury spectral line profiles were recorded using the McPherson model 209 spectrograph and the Andor ICCD camera as the detection system. This research presents Stark broadening parameters, the width (W) and the shift (d), of one Hg I, 19 Hg II, 6 Hg III and 4 Hg IV lines, not investigated so far. Our experimental W values were compared with the data calculated applying various approaches. The shape and intensity of astrophysically important 398.4 nm Hg II spectral line was discussed taking into account the isotope shift, hyperfine structure and Penning effects. At the mentioned plasma parameters the Stark broadening is found to be a main line broadening mechanism of the lines (λ > 200 nm) in the Hg I-IV spectra.

  10. The Mercury Laser Altimeter Instrument for the MESSENGER Mission

    Science.gov (United States)

    Cavanaugh, John F.; Smith, James C.; Sun, Xiaoli; Bartels, Arlin E.; Ramos-Izquierdo, Luis; Krebs, Danny J.; McGarry, Jan F.; Trunzo, Raymond; Novo-Gradac, Anne Marie; Britt, Jamie L.; Karsh, Jerry; Katz, Richard B.; Lukemire, Alan T.; Szymkiewicz, Richard; Berry, Daniel L.; Swinski, Joseph P.; Neumann, Gregory A.; Zuber, Maria T.; Smith, David E.

    2007-08-01

    The Mercury Laser Altimeter (MLA) is one of the payload science instruments on the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission, which launched on August 3, 2004. The altimeter will measure the round-trip time of flight of transmitted laser pulses reflected from the surface of the planet that, in combination with the spacecraft orbit position and pointing data, gives a high-precision measurement of surface topography referenced to Mercury’s center of mass. MLA will sample the planet’s surface to within a 1-m range error when the line-of-sight range to Mercury is less than 1,200 km under spacecraft nadir pointing or the slant range is less than 800 km. The altimeter measurements will be used to determine the planet’s forced physical librations by tracking the motion of large-scale topographic features as a function of time. MLA’s laser pulse energy monitor and the echo pulse energy estimate will provide an active measurement of the surface reflectivity at 1,064 nm. This paper describes the instrument design, prelaunch testing, calibration, and results of postlaunch testing.

  11. Environmental contamination and risk assessment of mercury from a historic mercury mine located in southwestern China.

    Science.gov (United States)

    Li, Yonghua

    2013-02-01

    A field survey of mercury pollution in environmental media and human hair samples obtained from residents living in the area surrounding the Chatian mercury mine (CMM) of southwestern China was conducted to evaluate the health risks of mercury to local residents. The results showed that mine waste, and tailings in particular, contained high levels of mercury and that the maximum mercury concentration was 88.50 μg g(-1). Elevated mercury levels were also found in local surface water, paddy soil, and paddy grain, which may cause severe health problems. The mercury concentration of hair samples from the inhabitants of the CMM exceeded 1.0 μg g(-1), which is the limit recommended by the US EPA. Mercury concentrations in paddy soil were positively correlated with mercury concentrations in paddy roots, stalks, and paddy grains, which suggested that paddy soil was the major source of mercury in paddy plant tissue. The average daily dose (ADD) of mercury for local adults and preschool children via oral exposure reached 0.241 and 0.624 μg kg(-1) body weight per day, respectively, which is approaching or exceeds the provisional tolerable daily intake. Among the three oral exposure routes, the greatest contributor to the ADD of mercury was the ingestion of rice grain. Open-stacked mine tailings have resulted in heavy mercury contamination in the surrounding soil, and the depth of appreciable soil mercury concentrations exceeded 100 cm.

  12. Mercury emission monitoring on municipal waste combustion

    International Nuclear Information System (INIS)

    Braun, H.; Gerig, A.

    1991-01-01

    In waste incineration, mercury is the only heavy metal to be released as a gas, mostly as mercury(II) chloride, because of its high volatility. Continuous emission monitoring is possible only when mercury occurs in its elemental form. This paper reports on various possibilities of converting Hg(II) into Hg(0) that has been studied and tested on a laboratory scale and in the TAMARA refuse incineration pilot facility. Continuous mercury emission measurement appears to be possible, provided mercury is converted in the flue gas condensate precipitated. The measuring results obtained on two municipal solid waste and on one sewage treatment sludge incineration plants show that the mercury monitor is a highly sensitive and selective continuously working instrument for mercury emission monitoring

  13. Fate of mercury in the Arctic (FOMA)

    DEFF Research Database (Denmark)

    Skov, H.; Christensen, J.; Asmund, G.

    This report is the final reporting of the project FONA, funded by the Danish Environmental Protection Agency with means from the MIKA/DANCEA funds for Environmental Support to the Arctic Region. The aim of the project is to study the intercompartment mercury transport chain in the arctic area. From...... atmospheric deposition of mercury on sea surfaces to uptake in marine organisms, bio-accumulation, and finally mercury levels in mammals. The studies in the project are focused on the behaviour of mercury during the spring period where special phenomena lead to an enhanced deposition of mercury in the Arctic...... environment, at a time where the marine ecosystem is particularly active. The studies also include a comprehensive time trend study of mercury in top carnivore species. Each of these studies contributes towards establishing the knowledge necessary to develop a general model for transport and uptake of mercury...

  14. Mercury in the environment : a review

    International Nuclear Information System (INIS)

    Goodarzi, F.

    2000-01-01

    Both geogenic and anthropogenic sources are responsible for the input of mercury into the environment. However, mercury comes mostly from geogenic sources and is found naturally in air, water and soil. Crustal degassing results in emission of mercury into the atmosphere. Mercury in water and soil is due mostly to input from sedimentary rocks. Mercury in lake sediments is related mainly to input by country rock and anthropogenic activities such as agriculture. The mercury content of coal is similar to or less than the amount found in the earths crust. Natural charcoal is also able to capture mercury at low temperature combustion. The amount of mercury emitted from the stack of coal-fired power plants is related to the nature of the milled coal and its mineralogical and elemental content. Mercury emissions originating from the combustion of coal from electric utility power plants are considered to be among the greatest contributors to global mercury air emissions. In order to quantify the impact the electric power industry has on the environment, information regarding mercury concentrations in coal and their speciation is needed. For this reason the author examined the behaviour of mercury in three coal samples ashed at increasing temperatures. Mercury removal from coal-fired power plants ranges from 10 to 50 per cent by fabric filters and 20 to 95 per cent by FGD systems. This data will help in regulating emissions of hazardous air pollutants from electric utility steam generating units and will potentially provide insight into the industry's contribution to the global mercury burden. 50 refs

  15. Mercury contamination in Khramulia (Capoeta capoeta) from the Cheshme Kile and Zarrin Gol Rivers in Iran and human health risk assessment.

    Science.gov (United States)

    Malvandi, Hassan; Sari, Abbas Esmaili; Aliabadian, Mansour

    2014-10-01

    Total mercury concentrations were determined in muscle tissue of Khramulia (Capoeta capoeta) captured in the Cheshme Kile and Zarrin Gol Rivers, Iran. In Cheshme Kile River, 49 fish samples were collected. The mean total mercury concentration in the muscles of C. capoeta from this area was 249 ng g(-1) dw. In Zarrin Gol River, where 62 fish samples were collected, the total mercury in muscles averaged 164 ng g(-1) dw. A significant difference was found between means of mercury in the rivers (p < 0.001). All samples from the two rivers had mean mercury concentrations below the maximum allowable limits for mercury set by the Food and Agriculture Organization, World Health Organization, Standardization Administration of China and Environmental Protection Agency. The results of this study indicate that the values of hazard target quotient and estimated weekly intake are low and represent a negligible risk for human health.

  16. Mercury biogeochemistry: Paradigm shifts, outstanding issues and research needs

    Science.gov (United States)

    Sonke, Jeroen E.; Heimbürger, Lars-Eric; Dommergue, Aurélien

    2013-05-01

    Half a century of mercury research has provided scientists and policy makers with a detailed understanding of mercury toxicology, biogeochemical cycling and past and future impacts on human exposure. The complexity of the global biogeochemical mercury cycle has led to repeated and ongoing paradigm shifts in numerous mercury-related disciplines and outstanding questions remain. In this review, we highlight some of the paradigm shifts and questions on mercury toxicity, the risks and benefits of seafood consumption, the source of mercury in seafood, and the Arctic mercury cycle. We see a continued need for research on mercury toxicology and epidemiology, for marine mercury dynamics and ecology, and for a closer collaboration between observational mercury science and mercury modeling in general. As anthropogenic mercury emissions are closely tied to the energy cycle (in particular coal combustion), mercury exposure to humans and wildlife are likely to persist unless drastic emission reductions are put in place.

  17. Novel methodology for the study of mercury methylation and reduction in sediments and water using 197Hg radiotracer

    International Nuclear Information System (INIS)

    Ribeiro Guevara, Sergio; Perez Catan, Soledad; Zizek, Suzana; Repinc, Urska; Jacimovic, Radojko; Horvat, Milena

    2007-01-01

    Mercury tracers are powerful tools that can be used to study mercury transformations in environmental systems, particularly mercury methylation, demethylation and reduction in sediments and water. However, mercury transformation studies using tracers can be subject to error, especially when used to assess methylation potential. The organic mercury extracted can be as low as 0.01% of the endogenous labeled mercury, and artefacts and contamination present during methylmercury (MeHg) extraction processes can cause interference. Solvent extraction methods based on the use of either KBr/H 2 SO 4 or HCl were evaluated in freshwater sediments using 197 Hg radiotracer. Values obtained for the 197 Hg tracer in the organic phase were up to 25-fold higher when HCl was used, which is due to the coextraction of 197 Hg 2+ into the organic phase during MeHg extraction. Evaluations of the production of MeHg gave similar results with both MeHg extraction procedures, but due to the higher Hg 2+ contamination of the controls, the uncertainty in the determination was higher when HCl was used. The Hg 2+ contamination of controls in the HCl extraction method showed a nonlinear correlation with the humic acid content of sediment pore water. Therefore, use of the KBr/H 2 SO 4 method is recommended, since it is free from these interferences. 197 Hg radiotracer (T 1/2 = 2.673 d) has a production rate that is about 50 times higher than that of 203 Hg (T 1/2 46.595 d), the most frequently used mercury radiotracer. Hence it is possible to obtain a similar level of performance to 203 Hg when it is used it in short-term experiments and produced by the irradiation of 196 Hg with thermal neutrons, using mercury targets with the natural isotopic composition. However, if the 0.15% natural abundance of the 196 Hg isotope is increased, the specific activity of the 197 Hg tracer can be significantly improved. In the present work, 197 Hg tracer was produced from mercury 51.58% enriched in the 196 Hg

  18. Novel biomarkers of mercury-induced autoimmune dysfunction: a Cross-sectional study in Amazonian Brazil

    Science.gov (United States)

    Motts, Jonathan A.; Shirley, Devon L.; Silbergeld, Ellen K.; Nyland, Jennifer F.

    2014-01-01

    Mercury is an ubiquitous environmental contaminant, causing both neurotoxicity and immunotoxicity. Given its ability to amalgamate gold, mercury is frequently used in small-scale artisanal gold mining. We have previously reported that elevated serum titers of antinuclear autoantibodies (ANA) are associated with mercury exposures of miners in gold mining. The goal of this project was to identify novel serum biomarkers of mercury-induced immunotoxicity and autoimmune dysregulation. We conducted an analysis of serum samples from a cross-sectional epidemiological study on miners working in Amazonian Brazil. In proteomic screening analyses, samples were stratified based on mercury concentrations and ANA titer and a subset of serum samples (N=12) were profiled using Immune Response Biomarker Profiling ProtoArray protein microarray for elevated autoantibodies. Of the up-regulated autoantibodies in the mercury-exposed cohort, potential target autoantibodies were selected based on relevance to pro-inflammatory and macrophage activation pathways. ELISAs were developed to test the entire sample cohort (N=371) for serum titers to the highest of these autoantibodies (anti-glutathione S-transferase alpha, GSTA1) identified in the high mercury/high ANA group. We found positive associations between elevated mercury exposure and up-regulated serum titers of 3760 autoantibodies as identified by ProtoArray. Autoantibodies identified as potential novel biomarkers of mercury-induced immunotoxicity include antibodies to the following proteins: GSTA1, tumor necrosis factor ligand superfamily member 13, linker for activation of T cells, signal peptide peptidase like 2B, stimulated by retinoic acid 13, and interferon induced transmembrane protein. ELISA analyses confirmed that mercury-exposed gold miners had significantly higher serum titers of anti-GSTA1 autoantibody [unadjusted odds ratio = 89.6; 95% confidence interval: 27.2, 294.6] compared to emerald miners (referent population

  19. Touchstones and mercury at Hedeby

    Czech Academy of Sciences Publication Activity Database

    Ježek, Martin; Holub, M.

    2014-01-01

    Roč. 89, č. 1 (2014), s. 193-204 ISSN 0079-4848 Institutional support: RVO:67985912 Keywords : Hedeby * Viking Age * grave goods * touchstone * precious metal * mercury * chemical microanalysis * archaeometallurgy Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 0.278, year: 2014

  20. PERCEPTION OF MERCURY RISK INFORMATION

    Science.gov (United States)

    Approximately 8% of American women have blood Mercury levels exceeding the EPA reference dose (a dose below which symptoms would be unlikely). The children of these women are at risk of neurological deficits (lower IQ scores) primarily because of the mother's consumption of conta...

  1. A downstream voyage with mercury

    Science.gov (United States)

    Heinz, Gary

    2016-01-01

    Retrospective essay for the Bulletin of Environmental Contamination and Toxicology.As I look back on my paper, “Effects of Low Dietary Levels of Methyl Mercury on Mallard Reproduction,” published in 1974 in the Bulletin of Environmental Contamination and Toxicology, a thought sticks in my mind. I realize just how much my mercury research was not unlike a leaf in a stream, carried this way and that, sometimes stalled in an eddy, restarted, and carried downstream at a pace and path that was not completely under my control. I was hired in 1969 by the Patuxent Wildlife Research Center to study the effects of environmental pollutants on the behavior of wildlife. A colleague was conducting a study on the reproductive effects of methylmercury on mallards (Anas platyrhynchos), and he offered to give me some of the ducklings. I conducted a pilot study, testing how readily ducklings approached a tape-recorded maternal call. Sample sizes were small, but the results suggested that ducklings from mercury-treated parents behaved differently than controls. That’s how I got into mercury research—pretty much by chance.

  2. Venus and Mercury as Planets

    Science.gov (United States)

    1974-01-01

    A general evolutionary history of the solar planetary system is given. The previously observed characteristics of Venus and Mercury (i.e. length of day, solar orbit, temperature) are discussed. The role of the Mariner 10 space probe in gathering scientific information on the two planets is briefly described.

  3. Venus and Mercury as planets

    International Nuclear Information System (INIS)

    1974-01-01

    A general evolutionary history of the solar planetary system is given. The previously observed characteristics of Venus and Mercury (i.e. length of day, solar orbit, temperature) are discussed. The role of the Mariner 10 space probe in gathering scientific information on the two planets is briefly described

  4. EURISOL-DS MULTI-MW TARGET ISSUES: BEAM WINDOW AND TRANSVERSE FILM TARGET

    CERN Document Server

    Adonai Herrera-Martínez, Yacine Kadi

    The analysis of the EURISOL-DS Multi_MW target precise geometry (Fig.1) has proved that large fission yields can be achieved with a 4 MW, providing a technically feasible design to evacuate the power deposited in the liquid mercury. Different designs for the mercury flow have been proposed, which maintain its temperature below the boiling point with moderate flow speeds (maximum 4 m/s).

  5. Multi-MW target station: Beam Window Issues and Transverse Film Target

    CERN Document Server

    Herrera-Martinez, A

    The analysis of the EURISOL-DS Multi_MW target precise geometry has proved that large fission yields can be achieved with a 4 MW, providing a technically feasible design to evacuate the power deposited in the liquid mercury. Different designs for the mercury flow have been proposed, which maintain its temperature below the boiling point with moderate flow speeds (maximum 4 m/s).

  6. 76 FR 75446 - Amendment of Class E Airspace; Mercury, NV

    Science.gov (United States)

    2011-12-02

    ...-0894; Airspace Docket No. 11-AWP-14] Amendment of Class E Airspace; Mercury, NV AGENCY: Federal... Mercury, Desert Rock Airport, Mercury, NV. Decommissioning of the Mercury Non-Directional Beacon (NDB) at Mercury, Desert Rock Airport has made this action necessary for the safety and management of Instrument...

  7. Electrochemical Reduction of Isatin-monohydrazone on Mercury Electrode

    Directory of Open Access Journals (Sweden)

    Ender Biçer

    2015-07-01

    Full Text Available Electrochemical behaviour of isatin monohydrazone (IM on a hanging mercury drop electrode in the Britton-Robinson (B-R buffer solution of pH = 2.00–9.00 has been investigated using square-wave voltammetry (SWV and cyclic voltammetry (CV techniques. In the pH range of 2.00–5.00, the voltammogram of IM exhibited a single cathodic irreversible peak. When the pH value exceeds 5.00, a new cathodic irreversible peak was also seen. According to the voltammetric data, a plausible electrode reaction mechanism of IM was proposed. The first reduction peak of IM is resulted from the reduction of =N–NH– group with consumption of 2e–/2H+. Also, its second cathodic peak is formed by the participation of 2e–/2H+ for the reduction of –N=N– group on its tautomeric form.

  8. The Plasma Environment at Mercury

    Science.gov (United States)

    Raines, James M.; Gershman, Daniel J.; Zurbuchen, Thomas H.; Gloeckler, George; Slavin, James A.; Anderson, Brian J.; Korth, Haje; Krimigis, Stamatios M.; Killen, Rosemary M.; Sarantos, Menalos; hide

    2011-01-01

    Mercury is the least explored terrestrial planet, and the one subjected to the highest flux of solar radiation in the heliosphere. Its highly dynamic, miniature magnetosphere contains ions from the exosphere and solar wind, and at times may allow solar wind ions to directly impact the planet's surface. Together these features create a plasma environment that shares many features with, but is nonetheless very different from, that of Earth. The first in situ measurements of plasma ions in the Mercury space environment were made only recently, by the Fast Imaging Plasma Spectrometer (FIPS) during the MESSENGER spacecraft's three flybys of the planet in 2008-2009 as the probe was en route to insertion into orbit about Mercury earlier this year. Here. we present analysis of flyby and early orbital mission data with novel techniques that address the particular challenges inherent in these measurements. First. spacecraft structures and sensor orientation limit the FIPS field of view and allow only partial sampling of velocity distribution functions. We use a software model of FIPS sampling in velocity space to explore these effects and recover bulk parameters under certain assumptions. Second, the low densities found in the Mercury magnetosphere result in a relatively low signal-to-noise ratio for many ions. To address this issue, we apply a kernel density spread function to guide removal of background counts according to a background-signature probability map. We then assign individual counts to particular ion species with a time-of-flight forward model, taking into account energy losses in the carbon foil and other physical behavior of ions within the instrument. Using these methods, we have derived bulk plasma properties and heavy ion composition and evaluated them in the context of the Mercury magnetosphere.

  9. Environmental Mercury and Its Toxic Effects

    Directory of Open Access Journals (Sweden)

    Kevin M. Rice

    2014-03-01

    Full Text Available Mercury exists naturally and as a man-made contaminant. The release of processed mercury can lead to a progressive increase in the amount of atmospheric mercury, which enters the atmospheric-soil-water distribution cycles where it can remain in circulation for years. Mercury poisoning is the result of exposure to mercury or mercury compounds resulting in various toxic effects depend on its chemical form and route of exposure. The major route of human exposure to methylmercury (MeHg is largely through eating contaminated fish, seafood, and wildlife which have been exposed to mercury through ingestion of contaminated lower organisms. MeHg toxicity is associated with nervous system damage in adults and impaired neurological development in infants and children. Ingested mercury may undergo bioaccumulation leading to progressive increases in body burdens. This review addresses the systemic pathophysiology of individual organ systems associated with mercury poisoning. Mercury has profound cellular, cardiovascular, hematological, pulmonary, renal, immunological, neurological, endocrine, reproductive, and embryonic toxicological effects.

  10. Mercury Toxicity on Sodium Pump and Organoseleniums Intervention: A Paradox

    Directory of Open Access Journals (Sweden)

    Ige Joseph Kade

    2012-01-01

    Full Text Available Mercury is an environmental poison, and the damage to living system is generally severe. The severity of mercury poisoning is consequent from the fact that it targets the thiol-containing enzymes, irreversibly oxidizing their critical thiol groups, consequently leading to an inactivation of the enzyme. The Na+/K+-ATPase is a sulfhydryl protein that is sensitive to Hg2+ assault. On the other hand, organoseleniums are a class of pharmacologically promising compounds with potent antioxidant effects. While Hg2+ oxidizes sulfhydryl groups of Na+/K+-ATPase under in vitro and in vivo conditions, the organoselenium compounds inhibit Na+/K+-ATPase in vitro but enhance its activities under in vivo conditions with concomitant increase in the level of endogenous thiols. Paradoxically, it appears that these two thiol oxidants can be used to counteract one another under in vivo conditions, and this hypothesis serves as the basis for this paper.

  11. Mercury emissions from municipal solid waste combustors

    Energy Technology Data Exchange (ETDEWEB)

    1993-05-01

    This report examines emissions of mercury (Hg) from municipal solid waste (MSW) combustion in the United States (US). It is projected that total annual nationwide MSW combustor emissions of mercury could decrease from about 97 tonnes (1989 baseline uncontrolled emissions) to less than about 4 tonnes in the year 2000. This represents approximately a 95 percent reduction in the amount of mercury emitted from combusted MSW compared to the 1989 mercury emissions baseline. The likelihood that routinely achievable mercury emissions removal efficiencies of about 80 percent or more can be assured; it is estimated that MSW combustors in the US could prove to be a comparatively minor source of mercury emissions after about 1995. This forecast assumes that diligent measures to control mercury emissions, such as via use of supplemental control technologies (e.g., carbon adsorption), are generally employed at that time. However, no present consensus was found that such emissions control measures can be implemented industry-wide in the US within this time frame. Although the availability of technology is apparently not a limiting factor, practical implementation of necessary control technology may be limited by administrative constraints and other considerations (e.g., planning, budgeting, regulatory compliance requirements, etc.). These projections assume that: (a) about 80 percent mercury emissions reduction control efficiency is achieved with air pollution control equipment likely to be employed by that time; (b) most cylinder-shaped mercury-zinc (CSMZ) batteries used in hospital applications can be prevented from being disposed into the MSW stream or are replaced with alternative batteries that do not contain mercury; and (c) either the amount of mercury used in fluorescent lamps is decreased to an industry-wide average of about 27 milligrams of mercury per lamp or extensive diversion from the MSW stream of fluorescent lamps that contain mercury is accomplished.

  12. Mercury exposure from interior latex paint.

    Science.gov (United States)

    Agocs, M M; Etzel, R A; Parrish, R G; Paschal, D C; Campagna, P R; Cohen, D S; Kilbourne, E M; Hesse, J L

    1990-10-18

    Many paint companies have used phenylmercuric acetate as a preservative to prolong the shelf life of interior latex paint. In August 1989, acrodynia, a form of mercury poisoning, occurred in a child exposed to paint fumes in a home recently painted with a brand containing 4.7 mmol of mercury per liter (at that time the Environmental Protection Agency's recommended limit was 1.5 mmol or less per liter). To determine whether the recent use of that brand of paint containing phenylmercuric acetate was associated with elevated indoor-air and urinary mercury concentrations, we studied 74 "exposed" persons living in 19 homes recently painted with the brand and 28 "unexposed" persons living in 10 homes not recently painted with paint containing mercury. The paint samples from the homes of exposed persons contained a median of 3.8 mmol of mercury per liter, and air samples from the homes had a median mercury content of 10.0 nmol per cubic meter (range, less than 0.5 to 49.9). No mercury was detected in paint or air samples from the homes of unexposed persons. The median urinary mercury concentration was higher in the exposed persons (4.7 nmol of mercury per millimole of creatinine; range, 1.4 to 66.5) than in the unexposed persons (1.1 nmol per millimole; range, 0.02 to 3.9; P less than 0.001). Urinary mercury concentrations within the range that we found in exposed persons have been associated with symptomatic mercury poisoning. We found that potentially hazardous exposure to mercury had occurred among persons whose homes were painted with a brand of paint containing mercury at concentrations approximately 2 1/2 times the Environmental Protection Agency's recommended limit.

  13. Bubble dynamics and sonoluminescence from helium or xenon in mercury and water.

    Science.gov (United States)

    Yasui, Kyuichi; Kato, Kazumi

    2012-09-01

    Numerical simulations of bubble pulsation and sonoluminescence (SL) have been performed for helium or xenon bubbles in mercury and water under the experimental conditions of Futakawa et al. [M. Futakawa, T. Naoe, and M. Kawai, in Nonlinear Acoustics-Fundamentals and Applications: 18th International Symposium on Nonlinear Acoustics (ISNA 18), AIP Conf. Proc. No. 1022, edited by B. O. Enflo, C. M. Hedberg, and L. Kari (AIP, New York, 2008), p. 197]. The results of the numerical simulations have revealed that the bubble expansion is much larger in water than in mercury mainly because the density of water is one order of magnitude smaller than that of mercury. The SL intensity is higher in water than that in mercury although the maximum bubble temperature is lower. This is caused by the much larger amount of vapor inside a bubble as the saturated vapor pressure of water is four orders of magnitude larger than that of mercury at room temperature. The SL intensity from xenon is much larger than that from helium due both to lower ionization potential and higher bubble temperature due to lower thermal conductivity. The instantaneous SL power may be as large as 200 W from xenon in water. The maximum temperature inside a xenon bubble in mercury may be as high as about 80 000 K. It is suggested that the maximum pressure in mercury due to shock waves emitted from bubbles increases as the SL intensity increases, although they are not simply correlated in water because the amount of water vapor trapped inside a bubble influences the SL intensity in a complex way.

  14. JV Task 122 - Assessment of Mercury Control Options for the San Miguel Electric Cooperative Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Nicholas Lentz; Brandon Pavlish; John Kay; Michael Jones

    2009-02-01

    In the United States, testing has been under way at electric coal-fired power plants to find viable and economical mercury control strategies to meet pending regulations. San Miguel Electric Cooperative (SMEC) engaged the Energy & Environmental Research Center (EERC) through a request for proposal (RFP) to perform research tests to evaluate sorbent-based technologies at its coal-fired San Miguel Generating Station to identify possible technology options that could be used by SMEC to meet the mercury reduction requirements of future U.S. federal standards. The goal of the testing was to target a mercury removal of {ge}90%. The EERC has successfully field-tested several sorbent-based technologies in previous projects that offer promise and potential to achieve a target removal of {ge}90%. Based on these field test results, yet recognizing that fuel type and plant operating conditions affect mercury capture significantly, the EERC proposed research tests to evaluate potential sorbent-based technologies provided by Norit Americas and the EERC that could potentially meet SMEC's mercury control objectives. Over the period of May through mid-June 2008, the EERC tested injection of both treated and nontreated activated carbon (AC) provided by Norit Americas and sorbent enhancement additives (SEAs) provided by the EERC. Tests were performed at San Miguel Unit 1 (450 MW) and included injection at the inlet of the air heater (AH) (temperature of 720 F). The test coal was a Texas lignite fuel with an average moisture content of 31.19%, an ash content of 26.6%, a heating value of 5,094 Btu/lb, a sulfur content of 2.7%, and a mercury concentration of 0.182 ppm, all reported on an as-received basis. Pilot-scale testing results identified DARCO{reg_sign} Hg-LH, SEA2 + DARCO{reg_sign} Hg, and the ChemMod sorbents as technologies with the potential to achieve the target mercury removal of {ge}90% at the full-scale test. Mercury concentrations were tracked with continuous

  15. An Epidemiological Study of Mercury Sensitization

    Directory of Open Access Journals (Sweden)

    Kazuhiro Sato

    1997-01-01

    Full Text Available Mercury sensitization has been historically in question and may be related to recent increases of type I allergic diseases. To clarify the epidemiological factors of mercury sensitization, we investigated factors relating to mercury sensitization in 215 medical students. Their allergic symptoms, family histories and lifestyles were studied by questionnaire. Patch tests were performed with HgCI2 (0.05% aq. and NiS04 (5% aq.. Anti- Dermatophagoides and anti-Crypfomeria pollen IgE antibodies in sera were also measured. Urinary mercury concentrations were measured in 25 mercury sensitized and 44 non-sensitized subjects (controls. Hair mercury concentrations were also measured in 19 sensitized and 22 non-sensitized subjects. While the positive rate of nickel was 6.0% (13/215, that of mercury was high (13.0%; 28/215. The subjects' individual histories of allergic rhinitis, eczema, urticaria and allergic conjunctivitis were significantly associated with family histories of these conditions (P<0.01, P<0.005 and P<0.005, respectively, as reported in the literature. However, no allergen- specific antibody positivity or past history of allergic disease was associated with mercury sensitization. Mercury sensitized subjects had experienced eczema caused by cosmetics, shampoos, soaps and haircreams significantly more frequently (P<0.05. The history of mercurochrome usage was not associated with mercury sensitization. The number of teeth treated with metals in mercury sensitized subjects was significantly higher than that in the control group (6.8±4.3 vs 4.8±1; P<0.05. There were significant differences in urinary mercury concentrations (specific gravity adjusted levels between mercury sensitized subjects and non-sensitized subjects (2.0±0.9 and 1.3±0.6 (xg/L, respectively; P<0.001. There were also significant differences in hair mercury concentrations between mercury sensitized and non-sensitized subjects (2.0±0.9 and 1.2±0.5 μg/g, respectively; P<0

  16. Total mercury loadings in sediment from gold mining and conservation areas in Guyana.

    Science.gov (United States)

    Howard, Joniqua; Trotz, Maya A; Thomas, Ken; Omisca, Erlande; Chiu, Hong Ting; Halfhide, Trina; Akiwumi, Fenda; Michael, Ryan; Stuart, Amy L

    2011-08-01

    The Low Carbon Development Strategy proposed in June 2009 by the government of Guyana in response to the Reducing Emissions from Deforestation and Forest Degradation in Developing Countries program has triggered evaluation of forest-related activities, thereby acting as a catalyst for improvements in Guyana's small- to medium-scale gold mining industry. This has also shed light on areas committed to conservation, something that has also been handled by Non Governmental Organizations. This paper compares water quality and mercury concentrations in sediment from four main areas in Guyana, two that are heavily mined for gold using mercury amalgamation methods (Arakaka and Mahdia) and two that are considered conservation areas (Iwokrama and Konashen). Fifty-three sediment and soil mercury loadings ranged from 29 to 1,200 ng/g and averaged 215 ± 187 ng/g for all sites with similar averages in conservation and mining areas. Sediment loadings are within the range seen in French Guiana and Suriname, but conservation area samples had higher loadings than the corresponding uncontaminated baselines. Type of ore and location in the mining process seemed to influence mercury loadings. Mercury sediment loadings were slightly positively correlated with pH (correlation coefficient = 0.2; p value < 0.001) whereas no significant correlations were found with dissolved oxygen or turbidity.

  17. Evaluation of activated carbon for control of mercury from coal-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S.; Laudal, D.; Dunham, G. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-11-01

    The ability to remove mercury from power plant flue gas may become important because of the Clean Air Act amendments` requirement that the U.S. Environmental Protection Agency (EPA) assess the health risks associated with these emissions. One approach for mercury removal, which may be relatively simple to retrofit, is the injection of sorbents, such as activated carbon, upstream of existing particulate control devices. Activated carbon has been reported to capture mercury when injected into flue gas upstream of a spray dryer baghouse system applied to waste incinerators or coal-fired boilers. However, the mercury capture ability of activated carbon injected upstream of an electrostatic precipitator (ESP) or baghouse operated at temperatures between 200{degrees} and 400{degrees}F is not well known. A study sponsored by the U.S. Department of Energy and the Electric power Research Institute is being conducted at the University of North Dakota Energy & Environmental Research Center (EERC) to evaluate whether mercury control with sorbents can be a cost-effective approach for large power plants. Initial results from the study were reported last year. This paper presents some of the recent project results. Variables of interest include coal type, sorbent type, sorbent addition rate, collection media, and temperature.

  18. Mercury Phase II Study - Mercury Behavior across the High-Level Waste Evaporator System

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, C. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Jackson, D. G. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Shah, H. B. [Savannah River Remediation, LLC., Aiken, SC (United States); Jain, V. [Savannah River Remediation, LLC., Aiken, SC (United States); Occhipinti, J. E. [Savannah River Remediation, LLC., Aiken, SC (United States); Wilmarth, W. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-06-17

    The Mercury Program team’s effort continues to develop more fundamental information concerning mercury behavior across the liquid waste facilities and unit operations. Previously, the team examined the mercury chemistry across salt processing, including the Actinide Removal Process/Modular Caustic Side Solvent Extraction Unit (ARP/MCU), and the Defense Waste Processing Facility (DWPF) flowsheets. This report documents the data and understanding of mercury across the high level waste 2H and 3H evaporator systems.

  19. Assessing Mercury and Methylmercury Bioavailability in Sediment Pore Water Using Mercury-Specific Hydrogels

    Science.gov (United States)

    2015-06-01

    FINAL REPORT Assessing Mercury and Methylmercury Bioavailability in Sediment Pore Water Using Mercury -Specific Hydrogels SERDP Project ER-1771...From - To) 2010-2015 4. TITLE AND SUBTITLE Assessing Mercury and Methylmercury Bioavailability in 5a. CONTRACT NUMBER W912HQ-10-C-0069 Sediment...Using Mercury -Specific DGTs 5b. GRANT NUMBER ER-1771 5c. PROGRAM ELEMENT NUMBER NA 6. AUTHOR(S) Magar, Victor S.*, Steenhaut, Nicholas

  20. Mercury concentrations at a historically mercury-contaminated site in KwaZulu-Natal, South Africa

    CSIR Research Space (South Africa)

    Williams, CR

    2011-02-01

    Full Text Available . Biogeochem., 43:237?257 Barrat GJ, Combrink J (2002) An Assessment of the degree of mercury (Hg) bio-transformation in two river systems following discharges from a mercury recovery plant. Water SA Special Edition: WISA Proceedings 2002 Benoit JM... in mercury and methylmercury biogeochemical cycling and bioaccumulation within shallow estuaries. PhD thesis, University of Maryland, College Park Kim E-H, Mason RP, Porter ET, Soulen HL (2006) The impact of resuspension on sediment mercury dynamics...

  1. Amended Silicated for Mercury Control

    Energy Technology Data Exchange (ETDEWEB)

    James Butz; Thomas Broderick; Craig Turchi

    2006-12-31

    Amended Silicates{trademark}, a powdered, noncarbon mercury-control sorbent, was tested at Duke Energy's Miami Fort Station, Unit 6 during the first quarter of 2006. Unit 6 is a 175-MW boiler with a cold-side electrostatic precipitator (ESP). The plant burns run-of-the-river eastern bituminous coal with typical ash contents ranging from 8-15% and sulfur contents from 1.6-2.6% on an as-received basis. The performance of the Amended Silicates sorbent was compared with that for powdered activated carbon (PAC). The trial began with a period of baseline monitoring during which no sorbent was injected. Sampling during this and subsequent periods indicated mercury capture by the native fly ash was less than 10%. After the baseline period, Amended Silicates sorbent was injected at several different ratios, followed by a 30-day trial at a fixed injection ratio of 5-6 lb/MMACF. After this period, PAC was injected to provide a comparison. Approximately 40% mercury control was achieved for both the Amended Silicates sorbent and PAC at injection ratios of 5-6 lbs/MMACF. Higher injection ratios did not achieve significantly increased removal. Similar removal efficiencies have been reported for PAC injection trials at other plants with cold-side ESPs, most notably for plants using medium to high sulfur coal. Sorbent injection did not detrimentally impact plant operations and testing confirmed that the use of Amended Silicates sorbent does not degrade fly ash quality (unlike PAC). The cost for mercury control using either PAC or Amended Silicates sorbent was estimated to be equivalent if fly ash sales are not a consideration. However, if the plant did sell fly ash, the effective cost for mercury control could more than double if those sales were no longer possible, due to lost by-product sales and additional cost for waste disposal. Accordingly, the use of Amended Silicates sorbent could reduce the overall cost of mercury control by 50% or more versus PAC for locations where

  2. Percolation of cadmium across a mercury film

    International Nuclear Information System (INIS)

    Malek, K.; Gobal, F.

    2003-01-01

    Electrodeposition/dissolution of cadmium onto a film of mercury shows some deviations from the natural liquidity of mercury caused by the reduction of Cd onto it. Percolation and fractal analyzes were done on the surface and the bulk of the mercury film during diffusion of Cd species (atoms). These show that the fractal dimensions of the Cd-inserted mercury film are about 2.11 and 2.54 near the surface of the mercury film and at deeper points inside the film, respectively. The insertion process has a negligible effect on the surface morphology of the mercury film and there is a phase transition in the bulk, as well as a geometrical transition during the Cd-insertion (de-insertion) process. This corresponds to a percolation threshold of about 0.2 mol l -1 Cd content

  3. Mercury in dated Greenland marine sediments

    DEFF Research Database (Denmark)

    Asmund, G.; Nielsen, S.P.

    2000-01-01

    Twenty marine sediment cores from Greenland were analysed for mercury, and dated by the lead-210 method. In general the cores exhibit a mercury profile with higher mercury concentrations in the upper centimetres of the core. The cores were studied by linear regression of In Hg vs, age...... of the sediment for the youngest 100 years. As a rule the mercury decreased with depth in the sediment with various degrees of significance. The increase of the mercury flux during the last 100 years is roughly a doubling. The increase may be of anthropogenic origin as it is restricted to the last 100 years....... In four cores the concentration of manganese was found also to increase in the top layers indicating diagenesis. In the other cases the higher concentrations were not accompanied by higher manganese concentrations. The mercury flux to the sediment surface was generally proportional to the Pb-210 flux...

  4. Human accumulation of mercury in Greenland

    DEFF Research Database (Denmark)

    Johansen, P.; Mulvad, G.; Pedersen, H. S.

    2007-01-01

    In the Arctic, the traditional diet exposes its people to a high intake of mercury especially from marine mammals. To determine whether the mercury is accumulated in humans, we analyzed autopsy samples of liver, kidney and spleen from adult ethnic Greenlanders who died between 1990 and 1994 from...... a wide range of causes, natural and violent. Liver, kidney and spleen samples from between 33 and 71 case subjects were analyzed for total mercury and methylmercury, and liver samples also for selenium. Metal levels in men and women did not differ and were not related to age except in one case, i.......e. for total mercury in liver, where a significant declining concentration with age was observed. The highest total mercury levels were found in kidney followed by liver and spleen. Methylmercury followed the same pattern, but levels were much lower, constituting only 19% of the total mercury concentration...

  5. Acclimation of subsurface microbial communities to mercury

    DEFF Research Database (Denmark)

    de Lipthay, Julia R; Rasmussen, Lasse D; Øregaard, Gunnar

    2008-01-01

    We studied the acclimation to mercury of bacterial communities of different depths from contaminated and noncontaminated floodplain soils. The level of mercury tolerance of the bacterial communities from the contaminated site was higher than those of the reference site. Furthermore, the level...... of mercury tolerance and functional versatility of bacterial communities in contaminated soils initially were higher for surface soil, compared with the deeper soils. However, following new mercury exposure, no differences between bacterial communities were observed, which indicates a high adaptive potential...... of the subsurface communities, possibly due to differences in the availability of mercury. IncP-1 trfA genes were detected in extracted community DNA from all soil depths of the contaminated site, and this finding was correlated to the isolation of four different mercury-resistance plasmids, all belonging...

  6. Mercury and selenium in European catfish (Silurus glanis) from Northern Italian Rivers: can molar ratio be a predictive factor for mercury toxicity in a top predator?

    Science.gov (United States)

    Squadrone, S; Benedetto, A; Brizio, P; Prearo, M; Abete, M C

    2015-01-01

    The study of mercury and selenium bioaccumulation in fish is crucially important for evaluating the extent of contamination in freshwater environments, and the possible health risk posed for humans when the antagonistic interactions of these two elements are considered. Several factors affect the risk of mercury intake from fish consumption, including mercury levels, human consumption patterns, and sensitive populations (e.g., pregnant women, foetuses, young children and unknown genetic factors). The protective effects of selenium on mercury toxicity have been extensively publicised in recent years, particularly targeting fish consumers. In this study, mercury (Hg) and selenium (Se) concentrations were determined in the muscle of European catfish (Silurus glanis) collected from North Italian Rivers. Differences in mercury and selenium levels, as a function of size, gender and location were investigated. Hg was strongly related to length, gender and location, while Se levels are not dependent on fish size or location. The mean Se/Hg molar ratio was strongly affected by location, and significantly related to length and age. Selenium was in molar excess of mercury in all sites, with a rank order of mean Se/Hg molar ratio of the Parma River (2.55)>Po River (1.71)>Tanaro River (1.66)>Bormida River (1.36). However, in 37% of analyzed samples, Hg exceeded the maximum level set by 1881/2006/EC and 629/2008/EC in fish muscle. The molar ratio of Se/Hg was 0.5mg/kg), and therefore the mean molar ratio cannot be considered as a safety criterion in top predator fish. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Demonstration of ATG Process for Stabilizing Mercury (<260 ppm) Contaminated Mixed Waste. Mixed Waste Focus Area. OST Reference # 2407

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1999-09-01

    Mercury contaminated wastes in many forms are present at various U. S. Department of Energy (DOE) sites. Based on efforts led by the Mixed Waste Focus Area (MWFA) and its Mercury Working Group (HgWG), the inventory of wastes contaminated with <260 ppm mercury and with radionuclides stored at various DOE sites is estimated to be approximately 6,000 m3). At least 26 different DOE sites have this type of mixed low-level waste in their storage facilities. Extraction methods are required to remove mercury from waste containing >260 ppm levels, but below 260 ppm Hg contamination levels the U. S. Environmental Protection Agency (EPA) does not require removal of mercury from the waste. Steps must still be taken, however, to ensure that the final waste form does not leach mercury in excess of the limit for mercury prescribed in the Resource Conservation and Recovery Act (RCRA) when subjected to the Toxicity Characteristic Leaching Procedure (TCLP). At this time, the limit is 0.20 mg/L. However, in the year 2000, the more stringent Universal Treatment Standard (UTS) of 0.025 mg/L will be used as the target endpoint. Mercury contamination in the wastes at DOE sites presents a challenge because it exists in various forms, such as soil, sludges, and debris, as well as in different chemical species of mercury. Stabilization is of interest for radioactively contaminated mercury waste (<260 ppm Hg) because of its success with particular wastes, such as soils, and its promise of applicability to a broad range of wastes. However, stabilization methods must be proven to be adequate to meet treatment standards. It must also be proven feasible in terms of economics, operability, and safety. To date, no standard method of stabilization has been developed and proven for such varying waste types as those within the DOE complex.

  8. A comprehensive assessment of mercury exposure in penguin populations throughout the Southern Hemisphere: Using trophic calculations to identify sources of population-level variation.

    Science.gov (United States)

    Brasso, Rebecka L; Chiaradia, André; Polito, Michael J; Raya Rey, Andrea; Emslie, Steven D

    2015-08-15

    The wide geographic distribution of penguins (Order Sphenisciformes) throughout the Southern Hemisphere provided a unique opportunity to use a single taxonomic group as biomonitors of mercury among geographically distinct marine ecosystems. Mercury concentrations were compared among ten species of penguins representing 26 geographically distinct breeding populations. Mercury concentrations were relatively low (⩽2.00ppm) in feathers from 18/26 populations considered. Population-level differences in trophic level explained variation in mercury concentrations among Little, King, and Gentoo penguin populations. However, Southern Rockhopper and Magellanic penguins breeding on Staten Island, Tierra del Fuego, had the highest mercury concentrations relative to their conspecifics despite foraging at a lower trophic level. The concurrent use of stable isotope and mercury data allowed us to document penguin populations at the greatest risk of exposure to harmful concentrations of mercury as a result of foraging at a high trophic level or in geographic 'hot spots' of mercury availability. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Thiosulphate assisted phytoextraction of mercury contaminated soils at the Wanshan Mercury Mining District, Southwest China

    Directory of Open Access Journals (Sweden)

    J. Wang

    2013-10-01

    Full Text Available Wanshan, known as the “Mercury Capital” of China, is located in the Southwest of China. Due to the extensive mining and smelting works in the Wanshan area, the local ecosystem has been serious contaminated with mercury. In the present study, a number of soil samples were taken from the Wanshan mercury mining area and the mercury fractionations in soils were analyzed using sequential extraction procedure technique. The obtained results showed that the dominate mercury fractions (represent 95% of total mercury were residual and organic bound mercury. A field trial was conducted in a mercury polluted farmland at the Wanshan mercury mine. Four plant species Brassica juncea Czern. et Coss.var. ASKYC (ASKYC, Brassica juncea Czern. et Coss.var.DPDH (DPDH, Brassica juncea Czern. et Coss.var.CHBD(CHBD, Brassica juncea Czern. et Coss.var.LDZY (LDZY were tested their ability to extract mercury from soil with thiosulphate amendment. The results indicated that the mercury concentration in the roots and shoots of the four plants were significantly increased with thiosulphate treatment. The mercury phytoextraction yield of ASKYC, DPDH, CHBD and LDZY were 92, 526, 294 and 129 g/ha, respectively

  10. Blood Mercury Levels of Zebra Finches Are Heritable: Implications for the Evolution of Mercury Resistance.

    Directory of Open Access Journals (Sweden)

    Kenton A Buck

    Full Text Available Mercury is a ubiquitous metal contaminant that negatively impacts reproduction of wildlife and has many other sub-lethal effects. Songbirds are sensitive bioindicators of mercury toxicity and may suffer population declines as a result of mercury pollution. Current predictions of mercury accumulation and biomagnification often overlook possible genetic variation in mercury uptake and elimination within species and the potential for evolution in affected populations. We conducted a study of dietary mercury exposure in a model songbird species, maintaining a breeding population of zebra finches (Taeniopygia guttata on standardized diets ranging from 0.0-2.4 μg/g methylmercury. We applied a quantitative genetics approach to examine patterns of variation and heritability of mercury accumulation within dietary treatments using a method of mixed effects modeling known as the 'animal model'. Significant variation in blood mercury accumulation existed within each treatment for birds exposed at the same dietary level; moreover, this variation was highly repeatable for individuals. We observed substantial genetic variation in blood mercury accumulation for birds exposed at intermediate dietary concentrations. Taken together, this is evidence that genetic variation for factors affecting blood mercury accumulation could be acted on by selection. If similar heritability for mercury accumulation exists in wild populations, selection could result in genetic differentiation for populations in contaminated locations, with possible consequences for mercury biomagnification in food webs.

  11. Radioactive mercury distribution in biological fluids and excretion in human subjects after inhalation of mercury vapor

    International Nuclear Information System (INIS)

    Cherian, M.G.; Hursh, J.B.; Clarkson, T.W.; Allen, J.

    1978-01-01

    The distribution of mercury in red blood cells (RBCs) and plasma, and its excretion in urine and feces are described in five human subjects during the first 7 days following inhalation of radioactive mercury vapor. A major portion (98%) of radioactive mercury in whole blood is initially accumulated in the RBCs and is transferred partly to the plasma compartment until the ratio of mercury in RBCs to plasma is about 2 within 20 h. The cumulative urinary and fecal excretion of mercury for 7 days is about 11.6% of the retained dose, and is closely related to the percent decline in body burden of mercury. There is little correlation between either the urinary excretion and plasma radioactivity of mercury, or the specific activities of urine and plasma mercury, suggesting a mechanism other than a direct glomerular filtration involved in the urinary excretion of recently exposed mercury. These studies suggest that blood mercury levels can be used as an index of recent exposure, while urinary levels may be an index of renal concentration of mercury. However, there is no reliable index for mercury concentration in the brain

  12. Thiosulphate assisted phytoextraction of mercury contaminated soils at the Wanshan Mercury Mining District, Southwest China

    Directory of Open Access Journals (Sweden)

    J Wang

    2013-10-01

    Full Text Available Wanshan, known as the “Mercury Capital” of China, is located in the Southwest of China. Due to the extensive mining and smelting works in the Wanshan area, the local ecosystem has been serious contaminated with mercury. In the present study, a number of soil samples were taken from the Wanshan mercury mining area and the mercury fractionations in soils were analyzed using sequential extraction procedure technique. The obtained results showed that the dominate mercury fractions (represent 95% of total mercury were residual and organic bound mercury. A field trial was conducted in a mercury polluted farmland at the Wanshan mercury mine. Four plant species Brassica juncea Czern. et Coss.var. ASKYC (ASKYC, Brassica juncea Czern. et Coss.var.DPDH (DPDH, Brassica juncea Czern. et Coss.var.CHBD(CHBD, Brassica juncea Czern. et Coss.var.LDZY (LDZY were tested their ability to extract mercury from soil with thiosulphate amendment. The results indicated that the mercury concentration in the roots and shoots of the four plants were significantly increased with thiosulphate treatment. The mercury phytoextraction yield of ASKYC, DPDH, CHBD and LDZY were 92, 526, 294 and 129 g/ha, respectively.

  13. STRESS SENSITIVITY OF MERCURY INJECTION MEASUREMENTS

    OpenAIRE

    Guise, P; Grattoni, C; Allshorn, S; Fisher, QJ; Schiffer, A

    2017-01-01

    Many petrophysical properties (e.g. permeability, electrical resistivity etc.) of tight rocks are very stress sensitive. However, most mercury injection measurements are made using an instrument that does not apply a confining pressure to the samples. Here we further explore the implications of the use and analysis of data from mercury injection porosimetry or mercury capillary pressure measurements (MICP). Two particular aspects will be discussed. First, the effective stress acting on sample...

  14. Mercury in polar bears from Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Lentfer, J.W.; Galster, W.A.

    1987-04-01

    Alaskan polar bear (Ursus maritimus) muscle and liver samples collected in 1972 were analyzed for total mercury. Bears north of Alaska had more mercury than bears west of Alaska. The only difference between young and adult animals was in the northern area where adults had more mercury in liver tissue than young animals. Levels were probably not high enough to be a serious threat to bears.

  15. Process for removing mercury from aqueous solutions

    Science.gov (United States)

    Googin, John M.; Napier, John M.; Makarewicz, Mark A.; Meredith, Paul F.

    1986-01-01

    A process for removing mercury from water to a level not greater than two parts per billion wherein an anion exchange material that is insoluble in water is contacted first with a sulfide containing compound and second with a compound containing a bivalent metal ion forming an insoluble metal sulfide. To this treated exchange material is contacted water containing mercury. The water containing not more than two parts per billion of mercury is separated from the exchange material.

  16. Surface composition of Mercury from reflectance spectrophotometry

    Science.gov (United States)

    Vilas, Faith

    1988-01-01

    The controversies surrounding the existing spectra of Mercury are discussed together with the various implications for interpretations of Mercury's surface composition. Special attention is given to the basic procedure used for reducing reflectance spectrophotometry data, the factors that must be accounted for in the reduction of these data, and the methodology for defining the portion of the surface contributing the greatest amount of light to an individual spectrum. The application of these methodologies to Mercury's spectra is presented.

  17. Accumulation of mercury in selected plant species grown in soils contaminated with different mercury compounds

    International Nuclear Information System (INIS)

    Su, Yi; Han, Fengxiang; Shiyab, Safwan; Chen, Jian; Monts, David L.

    2007-01-01

    The objective of our research is to screen and search for suitable plant species for phyto-remediation of mercury-contaminated soil. Currently our effort is specifically focused on mercury removal from the U.S. Department of Energy (DOE) sites, where mercury contamination is a major concern. In order to cost effectively implement mercury remediation efforts, it is necessary now to obtain an improved understanding of biological means of removing mercury and mercury compounds.. Phyto-remediation is a technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. In particular, phyto-extraction is the uptake of contaminants by plant roots and translocation within the plants to shoots or leaves. Contaminants are generally removed by harvesting the plants. We have investigated phyto-extraction of mercury from contaminated soil by using some of the known metal-accumulating plants since no natural plant species with mercury hyper-accumulating properties has yet been identified. Different natural plant species have been studied for mercury uptake, accumulation, toxicity and overall mercury removal efficiency. Various mercury compounds, such as HgS, HgCl 2 , and Hg(NO 3 ) 2 , were used as contaminant sources. Different types of soil were examined and chosen for phyto-remediation experiments. We have applied microscopy and diffuse reflectance spectrometry as well as conventional analytical chemistry to monitor the phyto-remediation processes of mercury uptake, translocation and accumulation, and the physiological impact of mercury contaminants on selected plant species. Our results indicate that certain plant species, such as beard grass (Polypogon monospeliensis), accumulated a very limited amount of mercury in the shoots ( 2 powder, respectively; no visual stress symptoms were observed. We also studied mercury phyto-remediation using aged soils that contained HgS, HgCl 2 , or Hg(NO 3 ) 2 . We have found that up to hundreds

  18. Analysis of the health risk of exposure to breast milk mercury in infants in Taiwan.

    Science.gov (United States)

    Chien, Ling-Chu; Han, Bor-Cheng; Hsu, Chun-Sen; Jiang, Cheun-Bin; You, Hung-Jiun; Shieh, Ming-Jer; Yeh, Ching-Ying

    2006-06-01

    The aim of this study was to assess the total concentration and health risk to infants of breast milk mercury in urban mothers and mothers married to fishermen in relation to fish intake in Taiwan. A total of sixty-eight healthy mothers were recruited for the study. The breast milk mercury geometric mean concentration was 2.02 microgl(-1) (n=56, range: 0.24-9.45 microgl(-1)) for the city group and 2.04 microgl(-1) (n=12, range: 0.26-8.62 microgl(-1)) for the fishermen's group. Of the three sources of mercury exposure (i.e., ingestion (breast milk), inhalation (ambient air), and dermal exposure (shower)), breast-feeding was found to be the largest (96.3-99.6% of the total). From a Monte Carlo simulation, in which methyl mercury accounted for about 50% of total mercury, the hazard quotient (exposure estimate/oral minimal risk level or target organ toxicity dose) exceeded 1.0 for 12.9% of urban babies and 18.8% of fishermen's babies (chronic oral minimal risk level and target organ toxicity dose: 3 x 10(-4)mgkg(-1)d(-1)). The calculated mercury exposure was 3.02 x 10(-1) microgkg(-1)d(-1) for a 3.49 kg urban baby boy and 3.06 x 10(-1) microgkg(-1)d(-1) for a 3.44 kg urban baby girl. These results suggest the life style of mothers (eating raw fish and shellfish such as used in "Sashimi" and "Sushi," and vitamin supplementation) may influence the mercury concentration in breast milk.

  19. The Messenger Mission to Mercury

    CERN Document Server

    Domingue, D. L

    2007-01-01

    NASA’s MESSENGER mission, launched on 3 August, 2004 is the seventh mission in the Discovery series. MESSENGER encounters the planet Mercury four times, culminating with an insertion into orbit on 18 March 2011. It carries a comprehensive package of geophysical, geological, geochemical, and space environment experiments to complete the complex investigations of this solar-system end member, which begun with Mariner 10. The articles in this book, written by the experts in each area of the MESSENGER mission, describe the mission, spacecraft, scientific objectives, and payload. The book is of interest to all potential users of the data returned by the MESSENGER mission, to those studying the nature of the planet Mercury, and by all those interested in the design and implementation of planetary exploration missions.

  20. Augustus as Mercury at last

    Directory of Open Access Journals (Sweden)

    Paulo Martins

    2017-07-01

    Full Text Available My purpose in this paper is to investigate and to analyse the representation of Augustus as Mercury, and what this association may suggest and mean to the Romans from both the urbs and the prouinciae, focusing the epigraphy, the numismatic, and the literature. Furthermore, I review three researches that someway work this problem: Bandinelli, Zanker and Martins. Even though the associations between divinities and rulers were very common – Augustus represented as Apollo, Jupiter or Neptune; Tiberius as Apollo; Claudius as Jupiter; or Commodus as Hercules –, the discussion on the relationship between Augustus and Mercury is very rare in recent bibliography. The latest relevant research on this subject dates back to the first half of the twentieth century. Chittenden’s work on numismatic and Grether’s article on epigraphy are both very important. Thus, new evidences must be considered, so that we can further investigate these representations in the Roman world.

  1. Mercury dosing solutions for fluorescent lamps

    Energy Technology Data Exchange (ETDEWEB)

    Corazza, A; Boffito, C [SAES Getters S.p.A., Viale Italia 77, Lainate (MI) 20020 (Italy)], E-mail: alessio_corazza@saes-group.com

    2008-07-21

    A review of the different technologies used to dose mercury in fluorescent lamps is presented. Conventional liquid mercury dosing is gradually being replaced with more reliable and environmentally friendly solutions that enable a significant reduction of the amount of mercury introduced in the lamp, so as to cope with more stringent regulations issued to minimize the environmental impact of exhausted lamps. This paper will review the most advanced novel methods to assure an accurate and fine dosing of mercury in fluorescent lamps, especially focusing on solutions based on the use of solid alloys.

  2. Sorbents for mercury removal from flue gas

    Energy Technology Data Exchange (ETDEWEB)

    Granite, Evan J.; Hargis, Richard A.; Pennline, Henry W.

    1998-01-01

    A review of the various promoters and sorbents examined for the removal of mercury from flue gas is presented. Commercial sorbent processes are described along with the chemistry of the various sorbent-mercury interactions. Novel sorbents for removing mercury from flue gas are suggested. Since activated carbons are expensive, alternate sorbents and/or improved activated carbons are needed. Because of their lower cost, sorbent development work can focus on base metal oxides and halides. Additionally, the long-term sequestration of the mercury on the sorbent needs to be addressed. Contacting methods between the flue gas and the sorbent also merit investigation.

  3. Risk assessment of mercury contaminated sites

    International Nuclear Information System (INIS)

    Hempel, M.

    1993-01-01

    At two sites, highly contaminated with mercury, risk assessment was executed. Methods were developed to determine organomercury compounds in water, air and soil. Toxicity tests demonstrated the high toxicity of organomercury compounds compared to inorganic mercury. Besides highly toxic methylmercury, ethylmercury was found in soils close to a chemical plant in Marktredwitz. In ultrafiltration-experiments mercury showed great affinity to high molecular substances in water. Lysimeter-experiments proved, that organomercury compounds are adsorbed and transformed to inorganic and elemental mercury. (orig.) [de

  4. Alkaline sorbent injection for mercury control

    Science.gov (United States)

    Madden, Deborah A.; Holmes, Michael J.

    2002-01-01

    A mercury removal system for removing mercury from combustion flue gases is provided in which alkaline sorbents at generally extremely low stoichiometric molar ratios of alkaline earth or an alkali metal to sulfur of less than 1.0 are injected into a power plant system at one or more locations to remove at least between about 40% and 60% of the mercury content from combustion flue gases. Small amounts of alkaline sorbents are injected into the flue gas stream at a relatively low rate. A particulate filter is used to remove mercury-containing particles downstream of each injection point used in the power plant system.

  5. Apparatus for isotopic alteration of mercury vapor

    Science.gov (United States)

    Grossman, Mark W.; George, William A.; Marcucci, Rudolph V.

    1988-01-01

    An apparatus for enriching the isotopic Hg content of mercury is provided. The apparatus includes a reactor, a low pressure electric discharge lamp containing a fill including mercury and an inert gas. A filter is arranged concentrically around the lamp. In a preferred embodiment, constant mercury pressure is maintained in the filter by means of a water-cooled tube that depends from it, the tube having a drop of mercury disposed in it. The reactor is arranged around the filter, whereby radiation from said lamp passes through the filter and into said reactor. The lamp, the filter and the reactor are formed of a material which is transparent to ultraviolet light.

  6. Identification of elemental mercury in the subsurface

    Science.gov (United States)

    Jackson, Dennis G

    2015-01-06

    An apparatus and process is provided for detecting elemental mercury in soil. A sacrificial electrode of aluminum is inserted below ground to a desired location using direct-push/cone-penetrometer based equipment. The insertion process removes any oxides or previously found mercury from the electrode surface. Any mercury present adjacent the electrode can be detected using a voltmeter which indicates the presence or absence of mercury. Upon repositioning the electrode within the soil, a fresh surface of the aluminum electrode is created allowing additional new measurements.

  7. Coal fired flue gas mercury emission controls

    International Nuclear Information System (INIS)

    Wu, Jiang; Pan, Weiguo; Cao, Yan; Pan, Weiping

    2015-01-01

    Mercury (Hg) is one of the most toxic heavy metals, harmful to both the environment and human health. Hg is released into the atmosphere from natural and anthropogenic sources and its emission control has caused much concern. This book introduces readers to Hg pollution from natural and anthropogenic sources and systematically describes coal-fired flue gas mercury emission control in industry, especially from coal-fired power stations. Mercury emission control theory and experimental research are demonstrated, including how elemental mercury is oxidized into oxidized mercury and the effect of flue gas contents on the mercury speciation transformation process. Mercury emission control methods, such as existing APCDs (air pollution control devices) at power stations, sorbent injection, additives in coal combustion and photo-catalytic methods are introduced in detail. Lab-scale, pilot-scale and full-scale experimental studies of sorbent injection conducted by the authors are presented systematically, helping researchers and engineers to understand how this approach reduces the mercury emissions in flue gas and to apply the methods in mercury emission control at coal-fired power stations.

  8. Ocular disorders among workers exposed to mercury.

    Science.gov (United States)

    Gabal, M S; Raslan, O A

    1995-01-01

    Mercury vapor exposed workers may show ocular changes, as well as other systems affection. A sample of 84 workers in preparing mercury fulminate were examined for conjunctival corneal and lenticular manifestation of long duration exposure, together with mercury urinary output. Lens changes were found in 50% of the involved workers while keratopathy as recorded in 34.5% of them. No statistically significant association was found between the occurrence of eye lesions and levels of urinary elimination of mercury. These results suggest local absorption of this element is most probably the underlying cause of ocular affection.

  9. Increased mercury emissions from modern dental amalgams.

    Science.gov (United States)

    Bengtsson, Ulf G; Hylander, Lars D

    2017-04-01

    All types of dental amalgams contain mercury, which partly is emitted as mercury vapor. All types of dental amalgams corrode after being placed in the oral cavity. Modern high copper amalgams exhibit two new traits of increased instability. Firstly, when subjected to wear/polishing, droplets rich in mercury are formed on the surface, showing that mercury is not being strongly bonded to the base or alloy metals. Secondly, high copper amalgams emit substantially larger amounts of mercury vapor than the low copper amalgams used before the 1970s. High copper amalgams has been developed with focus on mechanical strength and corrosion resistance, but has been sub-optimized in other aspects, resulting in increased instability and higher emission of mercury vapor. This has not been presented to policy makers and scientists. Both low and high copper amalgams undergo a transformation process for several years after placement, resulting in a substantial reduction in mercury content, but there exist no limit for maximum allowed emission of mercury from dental amalgams. These modern high copper amalgams are nowadays totally dominating the European, US and other markets, resulting in significant emissions of mercury, not considered when judging their suitability for dental restoration.

  10. Side effects of mercury in dental amalgam

    Directory of Open Access Journals (Sweden)

    Titiek Berniyanti

    2008-03-01

    Full Text Available Dental amalgam is an alloy composed of mixture of approximately equal parts of elemental liquid mercury and an alloy powder. The popularity of amalgam arises from excellent long term performance, ease of use and low cost. Despite the popularity of dental amalgam as restorative material, there have been concerns regarding the potential adverse health and environmental effects arising from exposure to mercury in amalgam. They have long been believed to be of little significance as contributors to the overall body burden of mercury, because the elemental form of mercury is rapidly consumed in the setting reaction of the restoration. In 1997, 80% of dentist in Indonesia still using amalgam as an alternative material, and 60% of them treat the rest of unused amalgam carelessly. In recent years, the possible environmental and health impact caused by certain routines in dental practice has attracted attention among regulators. As part of point source reduction strategies, the discharge of mercury/amalgam-contaminated wastes has been regulated in a number of countries, even though it has been documented that by adopting appropriate mercury hygiene measures, the impact of amalgam use in dentistry is minimal. The purpose of this paper is to examine on studies that relate mercury levels in human to the presence of dental amalgams. It is concluded that even though mercury used in filling is hazardous, if normal occupational recommendations for proper mercury hygiene routines and source of reduction strategies are followed, no occupational health risk can be assumed.

  11. Observations of Mercury in 1988 and 1989

    International Nuclear Information System (INIS)

    Schmude, R.W. Jr.

    1990-01-01

    A visual study of the planet Mercury was carried out in May 1988 and in April and May 1989. Most of the observations were made with the 35.5-cm telescope at the Texas A ampersand M University Observatory. This report presents drawings and a map of Mercury that covers the longitude range of 195-285 deg. One important finding was that a polarizing filter combined with color filters gives a sharper view of the planet. It is also concluded that high-resolution images of Mercury's terminator, either as seen from the earth or with the Hubble Space Telescope, can provide information about Mercury's topography. 10 refs

  12. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2005-06-01

    Phytoremediation is defined as the use of plants to extract, resist, detoxify, and/or sequester toxic environmental pollutants. The long-term goal of the proposed research is to develop and test highly productive, field-adapted plant species that have been engineered for the phytoremediation of mercury. A variety of different genes, which should enable plants to clean mercury polluted sites are being tested as tools for mercury phytoremediation, first in model laboratory plants and then in potential field species. Several of these genes have already been shown to enhance mercury phytoremediation. Mercury pollution is a serious, world-wide problem affecting the health of human and wildlife populations. Environmentally, the most serious mercury threat is the production of methylmercury (CH3Hg+) by native bacteria at mercury contaminated wetland sites. Methylmercury is inherently more toxic than metallic (Hg(0)) or ionic (Hg(II)) mercury, and because methylmercury is prolifically biomagnified up the food chain, it poses the most immediate danger to animal populations. We have successfully engineered two model plants, Arabidopsis and tobacco, to use the bacterial merB gene to convert methylmercury to less toxic ionic mercury and to use the bacterial merA gene to further detoxify ionic mercury to the least toxic form of mercury, metallic mercury. Plants expressing both MerA and MerB proteins detoxify methylmercury in two steps to the metallic form. These plants germinate, grow, and set seed at normal growth rates on levels of methylmercury or ionic mercury that are lethal to normal plants. Our newest efforts involve engineering plants with several additional bacterial and plant genes that allow for higher levels of mercury resistance and mercury hyperaccumulation. The potential for these plants to hyperaccumulate mercury was further advanced by developing constitutive, aboveground, and root-specific gene expression systems. Our current strategy is to engineer plants to

  13. EDITORIAL: Mercury-free discharges for lighting

    Science.gov (United States)

    Haverlag, M.

    2007-07-01

    This special Cluster of articles in Journal of Physics D: Applied Physics covers the subject of mercury-free discharges that are being investigated by different light source researchers, as an alternative to existing mercury-containing lamps. The main driving force to move away from mercury-containing discharge light sources is connected to the environmentally unfriendly nature of mercury. After inhalation or direct contact, severe mercury exposure can lead to damage to human brain cells, the kidneys, the liver and the nervous system. For this reason, the use of mercury in products is becoming more and more restricted by different governmental bodies. In the lighting industry, however, many products still make use of mercury, for different reasons. The main reason is that mercury-containing products are, in most cases, more efficient than mercury-free products. For a realistic comparison of the environmental impact, the mercury-contamination due to electricity production must be taken into account, which depends on the type of fuel being used. For an average European fuel-mix, the amount of mercury that is released into the environment is around 29 μg kWh-1. This means that a typical 30 W TL lamp during a lifetime of 20,000 hours will release a total of about 20 mg mercury due to electricity production, which exceeds the total mercury dose in the lamp (more and more of which is being recycled) by a factor of 5-10 for a modern TL lamp. This illustrates that, quite apart from other environmental arguments like increased CO2 production, mercury-free alternatives that use more energy can in fact be detrimental for the total mercury pollution over the lifetime of the lamp. For this reason, the lighting industry has concentrated on lowering the mercury content in lamps as long as no efficient alternatives exist. Nevertheless, new initiatives for HID lamps and fluorescent lamps with more or less equal efficiency are underway, and a number of them are described in this

  14. Rapid Monitoring of Mercury in Air from an Organic Chemical Factory in China Using a Portable Mercury Analyzer

    OpenAIRE

    Yasutake, Akira; Cheng, Jin Ping; Kiyono, Masako; Uraguchi, Shimpei; Liu, Xiaojie; Miura, Kyoko; Yasuda, Yoshiaki; Mashyanov, Nikolay

    2011-01-01

    A chemical factory, using a production technology of acetaldehyde with mercury catalysis, was located southeast of Qingzhen City in Guizhou Province, China. Previous research showed heavy mercury pollution through an extensive downstream area. A current investigation of the mercury distribution in ambient air, soils, and plants suggests that mobile mercury species in soils created elevated mercury concentrations in ambient air and vegetation. Mercury concentrations of up to 600 ng/m3 in air o...

  15. Multiscale geomorphometric modeling of Mercury

    Science.gov (United States)

    Florinsky, I. V.

    2018-02-01

    Topography is one of the key characteristics of a planetary body. Geomorphometry deals with quantitative modeling and analysis of the topographic surface and relationships between topography and other natural components of landscapes. The surface of Mercury is systematically studied by interpretation of images acquired during the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission. However, the Mercurian surface is still little explored by methods of geomorphometry. In this paper, we evaluate the Mercury MESSENGER Global DEM MSGR_DEM_USG_SC_I_V02 - a global digital elevation model (DEM) of Mercury with the resolution of 0.015625° - as a source for geomorphometric modeling of this planet. The study was performed at three spatial scales: the global, regional (the Caloris basin), and local (the Pantheon Fossae area) ones. As the initial data, we used three DEMs of these areas with resolutions of 0.25°, 0.0625°, and 0.015625°, correspondingly. The DEMs were extracted from the MESSENGER Global DEM. From the DEMs, we derived digital models of several fundamental morphometric variables, such as: slope gradient, horizontal curvature, vertical curvature, minimal curvature, maximal curvature, catchment area, and dispersive area. The morphometric maps obtained represent peculiarities of the Mercurian topography in different ways, according to the physical and mathematical sense of a particular variable. Geomorphometric models are a rich source of information on the Mercurian surface. These data can be utilized to study evolution and internal structure of the planet, for example, to visualize and quantify regional topographic differences as well as to refine geological boundaries.

  16. Experimental Investigation of Magnetohydrodynamics Effects in Molten Metals and Study of Homogeneity of Radioactive Mercury Amalgams

    CERN Document Server

    Astone, A

    2002-01-01

    The high neutrino output demanded for a neutri no factory requests a high power proton beam interacting with a static target. The additional circumstances of limited space and long term stability ask for development of novel concepts for such types of targets. In our working group, part of the Neutri no Factory Working Group (NFWG) of CERN, we are investigating on the proton interaction with the mercury target. This is called the study of proton induced shocks in molten metal. In the US scheme for a neutrino factory the interaction between proton beam and the mercury jet target takes place inside a 20 Tesla solenoidal magnetic field, which serv es as a focusing device for the produced particles. This field of study is refe rred to as Magneto Hydrodynamics (MHD). The high power proton beam deposits a large amount of energy in the small volume of the target, which results in disruption. The aim is to establi...

  17. 49 CFR 179.200-10 - Welding.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Welding. 179.200-10 Section 179.200-10... Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.200-10 Welding. (a) All joints... W (IBR, see § 171.7 of this subchapter). Welding procedures, welders and fabricators shall be...

  18. 24 CFR 200.83 - Interest rate.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Interest rate. 200.83 Section 200... Eligibility Requirements for Existing Projects Mortgage Provisions § 200.83 Interest rate. (a) The mortgage shall bear interest at the rate agreed upon by the mortgagee and the mortgagor. (b) Interest shall be...

  19. 46 CFR 184.200 - General.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false General. 184.200 Section 184.200 Shipping COAST GUARD... MISCELLANEOUS SYSTEMS AND EQUIPMENT Cooking and Heating § 184.200 General. Cooking and heating equipment must be... restricted by § 184.202 of this part. ...

  20. 11 CFR 200.2 - Procedural requirements.

    Science.gov (United States)

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Procedural requirements. 200.2 Section 200.2 Federal Elections FEDERAL ELECTION COMMISSION ADMINISTRATIVE REGULATIONS PETITIONS FOR RULEMAKING § 200.2 Procedural requirements. (a) Any interested person may file with the Commission a written petition for the...

  1. 24 CFR 200.635 - Compliance.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Compliance. 200.635 Section 200.635... GENERAL INTRODUCTION TO FHA PROGRAMS Affirmative Fair Housing Marketing Regulations § 200.635 Compliance... Department will enforce compliance through the procedures outlined in 24 CFR part 108. [37 FR 75, Jan. 5...

  2. 21 CFR 131.200 - Yogurt.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Yogurt. 131.200 Section 131.200 Food and Drugs... CONSUMPTION MILK AND CREAM Requirements for Specific Standardized Milk and Cream § 131.200 Yogurt. (a) Description. Yogurt is the food produced by culturing one or more of the optional dairy ingredients specified...

  3. 17 CFR 200.63 - Commission opinions.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Commission opinions. 200.63 Section 200.63 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION ORGANIZATION; CONDUCT AND ETHICS; AND INFORMATION AND REQUESTS Canons of Ethics § 200.63 Commission opinions. The opinions...

  4. 17 CFR 200.552 - NEPA planning.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false NEPA planning. 200.552 Section 200.552 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION ORGANIZATION; CONDUCT... § 200.552 NEPA planning. Where it is reasonably foreseeable by the Commission that it may be required to...

  5. 10 CFR 1021.200 - DOE planning.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false DOE planning. 1021.200 Section 1021.200 Energy DEPARTMENT... Decisionmaking § 1021.200 DOE planning. (a) DOE shall provide for adequate and timely NEPA review of DOE... accordance with 40 CFR 1501.2 and this section. In its planning for each proposal, DOE shall include adequate...

  6. 46 CFR 403.200 - General.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false General. 403.200 Section 403.200 Shipping COAST GUARD (GREAT LAKES PILOTAGE), DEPARTMENT OF HOMELAND SECURITY GREAT LAKES PILOTAGE UNIFORM ACCOUNTING SYSTEM Inter-Association Settlements § 403.200 General. Each Association that shares revenues and expenses with...

  7. 17 CFR 200.50 - Authority.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Authority. 200.50 Section 200.50 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION ORGANIZATION; CONDUCT AND ETHICS; AND INFORMATION AND REQUESTS Canons of Ethics § 200.50 Authority. The Canons of Ethics for...

  8. 24 CFR 200.605 - Authority.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Authority. 200.605 Section 200.605... GENERAL INTRODUCTION TO FHA PROGRAMS Affirmative Fair Housing Marketing Regulations § 200.605 Authority. The regulations in this subpart are issued pursuant to the authority to issue regulations granted to...

  9. 17 CFR 200.56 - Personal conduct.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Personal conduct. 200.56 Section 200.56 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION ORGANIZATION; CONDUCT AND ETHICS; AND INFORMATION AND REQUESTS Canons of Ethics § 200.56 Personal conduct. Appointment to...

  10. 44 CFR 19.200 - Application.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Application. 19.200 Section 19.200 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... RECEIVING FEDERAL FINANCIAL ASSISTANCE Coverage § 19.200 Application. Except as provided in §§ 19.205...

  11. 14 CFR 1253.200 - Application.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Application. 1253.200 Section 1253.200 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NONDISCRIMINATION ON THE BASIS OF SEX IN EDUCATION PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Coverage § 1253.200 Application...

  12. 28 CFR 54.200 - Application.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Application. 54.200 Section 54.200 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) NONDISCRIMINATION ON THE BASIS OF SEX IN EDUCATION PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Coverage § 54.200 Application...

  13. 45 CFR 2555.200 - Application.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Application. 2555.200 Section 2555.200 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY SERVICE... Coverage § 2555.200 Application. Except as provided in §§ 2555.205 through 2555.235(a), these Title IX...

  14. 43 CFR 41.200 - Application.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Application. 41.200 Section 41.200 Public Lands: Interior Office of the Secretary of the Interior NONDISCRIMINATION ON THE BASIS OF SEX IN EDUCATION PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Coverage § 41.200 Application...

  15. 17 CFR 200.602 - Application.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Application. 200.602 Section 200.602 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION ORGANIZATION; CONDUCT... Programs or Activities Conducted by the Securities and Exchange Commission § 200.602 Application. This...

  16. 24 CFR 3.200 - Application.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Application. 3.200 Section 3.200 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development... Coverage § 3.200 Application. Except as provided in §§ 3.205 through 3.235(a), these Title IX regulations...

  17. SRXRF study of trace elements in hippocampus of pup rats after prenatal and postnatal exposure to low-level mercury

    International Nuclear Information System (INIS)

    Zhang Fang; Feng Weiyue; Chai Zhifang; Wang Meng; Shi Junwen; Huang Yuying; He Wei

    2005-01-01

    Since the pollution of mercury in the environment still keeps high, more and more concerns over mercury toxicity are focused on the potential risk associated with relatively low-dose and long-term mercury exposure in the environment. It is well known that fetus and developing children are the susceptive victims of mercury damage. Therefore, high attention is focused on whether the prenatal and postnatal exposure to relatively low level of mercury will be harmful to children development. Some epidemiological studies reported that the methylmercury-related neuropsychological deficits were mainly found in the domains of cognitional parts, such as language, attention, memory, and so forth, Our previous study found out that high level of mercury was accumulated in the pup hippocampus after their prenatal and postnatal exposure to low dose of inorganic mercury. Synchrotron radiation X-ray fluorescence technique (SRXRF) is characterized of its simultaneous determination of multi-elements, high sensitivity, small sampling amount and microanalysis. SRXRF does not cause the damage of irradiated samples. Thus, it makes possible to measure the distributions of trace elements in a selected area. In this study, in order to study the effects of low-level mercury exposure to pup rat brain, some oxidation-related elements, e.g. Cu, Fe and Mn in pup hippocampus after in utero and weaning exposure to low-level inorganic mercury were determined by SRXRF. The experiment was performed at a synchrotron radiation facility at Institute of High Energy Physics. And the spot size of the beam irradiating on the sample was adjusted to about 100 x 200 μm 2 , Each spot was irradiated for about 100 s. The spectra were analyzed by the AXIL program. Additionally, the activities of some important antioxidant enzymes, such as GSH-Px, SOD, CAT, were also measured together with the content of malondialdehyde (MDA). The results showed that mercury exposure could lead to significant increase of both

  18. Mercury removal from liquid and solid mixed waste

    International Nuclear Information System (INIS)

    Gates, D.D.; Klasson, K.T.; Corder, S.L.; Cameron, P.A.; Perona, J.J.

    1995-01-01

    Based on bench-scale laboratory experiments, the following conclusions were reached: Sulfur-impregnated, activated, carbon pellets (Mersorb) can be used to remove mercury (Hg 2+ ) to below EPA's toxic characteristic level (0.2 mg/L). Mersorb works under acid conditions (pH 2) but its capacity is reduced by approximately 50% compared with neutral conditions. Competing ions present in the target waste stream reduced the Mersorb capacity by 50%. Mersorb appears to be economical compared with leading ion exchange resin. KI/I 2 leaching solution can be used to remove up to 99% of Hg in contaminated soil and glass. KI/I 2 leaching solution worked well with several mercury species, including Hg 0 , HgO, HgS, and HgCl 2 . KI/I 2 leaching solution worked well with a wide variety of initial mercury concentrations. Radionuclide surrogate studies suggested that uranium will not partition into KI/I 2 leaching solutions. Cesium may partition into the KI/I 2 leaching solution because of the high solubility of cesium salts

  19. Maternal transfer of mercury to songbird eggs.

    Science.gov (United States)

    Ackerman, Joshua T; Hartman, C Alex; Herzog, Mark P

    2017-11-01

    We evaluated the maternal transfer of mercury to eggs in songbirds, determined whether this relationship differed between songbird species, and developed equations for predicting mercury concentrations in eggs from maternal blood. We sampled blood and feathers from 44 house wren (Troglodytes aedon) and 34 tree swallow (Tachycineta bicolor) mothers and collected their full clutches (n = 476 eggs) within 3 days of clutch completion. Additionally, we sampled blood and feathers from 53 tree swallow mothers and randomly collected one egg from their clutches (n = 53 eggs) during mid to late incubation (6-10 days incubated) to evaluate whether the relationship varied with the timing of sampling the mother's blood. Mercury concentrations in eggs were positively correlated with mercury concentrations in maternal blood sampled at (1) the time of clutch completion for both house wrens (R 2  = 0.97) and tree swallows (R 2  = 0.97) and (2) during mid to late incubation for tree swallows (R 2  = 0.71). The relationship between mercury concentrations in eggs and maternal blood did not differ with the stage of incubation when maternal blood was sampled. Importantly, the proportion of mercury transferred from mothers to their eggs decreased substantially with increasing blood mercury concentrations in tree swallows, but increased slightly with increasing blood mercury concentrations in house wrens. Additionally, the proportion of mercury transferred to eggs at the same maternal blood mercury concentration differed between species. Specifically, tree swallow mothers transferred 17%-107% more mercury to their eggs than house wren mothers over the observed mercury concentrations in maternal blood (0.15-1.92 μg/g ww). In contrast, mercury concentrations in eggs were not correlated with those in maternal feathers and, likewise, mercury concentrations in maternal blood were not correlated with those in feathers (all R 2  mercury concentrations from maternal blood to eggs

  20. Recovery of Mercury From Contaminated Liquid Wastes

    International Nuclear Information System (INIS)

    1998-01-01

    The Base Contract program emphasized the manufacture and testing of superior sorbents for mercury removal, testing of the sorption process at a DOE site, and determination of the regeneration conditions in the laboratory. During this project, ADA Technologies, Inc. demonstrated the following key elements of a successful regenerable mercury sorption process: (1) sorbents that have a high capacity for dissolved, ionic mercury; (2) removal of ionic mercury at greater than 99% efficiency; and (3) thermal regeneration of the spent sorbent. ADA's process is based on the highly efficient and selective sorption of mercury by noble metals. Contaminated liquid flows through two packed columns that contain microporous sorbent particles on which a noble metal has been finely dispersed. A third column is held in reserve. When the sorbent is loaded with mercury to the point of breakthrough at the outlet of the second column, the first column is taken off-line and the flow of contaminated liquid is switched to the second and third columns. The spent column is regenerated by heating. A small flow of purge gas carries the desorbed mercury to a capture unit where the liquid mercury is recovered. Laboratory-scale tests with mercuric chloride solutions demonstrated the sorbents' ability to remove mercury from contaminated wastewater. Isotherms on surrogate wastes from DOE's Y-12 Plant in Oak Ridge, Tennessee showed greater than 99.9% mercury removal. Laboratory- and pilot-scale tests on actual Y-12 Plant wastes were also successful. Mercury concentrations were reduced to less than 1 ppt from a starting concentration of 1,000 ppt. The treatment objective was 50 ppt. The sorption unit showed 10 ppt discharge after six months. Laboratory-scale tests demonstrated the feasibility of sorbent regeneration. Results show that sorption behavior is not affected after four cycles

  1. Worldwide trend of atmospheric mercury since 1995

    Directory of Open Access Journals (Sweden)

    F. Slemr

    2011-05-01

    Full Text Available Concern about the adverse effects of mercury on human health and ecosystems has led to tightening emission controls since the mid 1980s. But the resulting mercury emissions reductions in many parts of the world are believed to be offset or even surpassed by the increasing emissions in rapidly industrializing countries. Consequently, concentrations of atmospheric mercury are expected to remain roughly constant. Here we show that the worldwide atmospheric mercury concentrations have decreased by about 20 to 38 % since 1996 as indicated by long-term monitoring at stations in the Southern and Northern Hemispheres combined with intermittent measurements of latitudinal distribution over the Atlantic Ocean. The total reduction of the atmospheric mercury burden of this magnitude within 14 years is unusually large among most atmospheric trace gases and is at odds with the current mercury emission inventories with nearly constant anthropogenic emissions over this period. This suggests a major shift in the biogeochemical cycle of mercury including oceans and soil reservoirs. Decreasing reemissions from the legacy of historical mercury emissions are the most likely explanation for this decline since the hypothesis of an accelerated oxidation rate of elemental mercury in the atmosphere is not supported by the observed trends of other trace gases. Acidification of oceans, climate change, excess nutrient input and pollution may also contribute by their impact on the biogeochemistry of ocean and soils. Consequently, models of the atmospheric mercury cycle have to include soil and ocean mercury pools and their dynamics to be able to make projections of future trends.

  2. Mercury Methylation and Detoxification by Novel Microorganisms in Mercury Enriched Mesothermal Springs

    Science.gov (United States)

    Gionfriddo, C. M.; Krabbenhoft, D. P.; Stott, M.; Wick, R. R.; Schultz, M. B.; Holt, K. E.; Moreau, J. W.

    2015-12-01

    Hot springs and fumaroles release significant quantities of aqueous and gaseous mercury into the environment. Yet few studies have looked at the microbial underpinnings of mercury transformations in geothermal settings. Recent advancements in culture-independent molecular techniques, such as ultra-high-throughput sequencing, allow us to delve deeply into the functional and phylogenetic make-up of these extreme environments. Here we present results from deep metagenomic sequencing of geothermal microbial communities cycling mercury, focussing on the connections between putative metabolisms and mercury methylation, and the evolution of the mer-operon. Presented are data from two adjacent, acidic (pHNew Zealand), extremely enriched in total mercury (>1000 ng L-1), and varying methylmercury concentrations (1-10 ng L-1). Microbial communities of both springs are dominated by mercury resistant acidophilic, sulfur- and iron-cycling microbes: Acidithiobacillus, Thiomonas, and Thermoplasma. Mercury methylation genes (hgcAB) were only detected in the cooler spring (ΔT~10 °C), with an order of magnitude greater methylmercury (10 ng L-1). The hgcAB genes have no known closest relatives (40°C), and methylmercury concentration. We conclude that the relative amount of mercury methylation in each hot spring is controlled by the presence of methylating bacteria and archaea, the release of bioavailable mercury species from sulfide minerals, counterbalanced by microbial mercury demethylation and reduction and mercury sulfide mineralization.

  3. Mercury rising : mercury emissions from Ontario Power Generation's coal-fired plants

    International Nuclear Information System (INIS)

    Rang, S.

    2004-09-01

    Ontario Power Generation (OPG) operates 5 coal-fired power plants which are the largest single source of mercury emissions in Ontario. Mercury is a persistent, bioaccumulative neurotoxin which is considered toxic under the Canadian Environmental Protection Act. This report examines the health and environmental impacts of mercury, and the trends for mercury emission in Ontario. In 2002, the 5 coal-fired plants emitted 527 kg of mercury into the atmosphere and contributed 39 per cent of the total amount of mercury emitted into the air. While many other sectors have reduced their mercury emissions since 1988, Ontario's coal-fired plants have lagged behind and have actually increased mercury emissions by 16 per cent since 1988. This paper suggests that phasing out OPG coal-fired plants by 2007 could lead to a 39 per cent reduction in airborne mercury emissions. It would also allow Ontario to achieve the Canada Wide Standard for mercury emissions 3 years early, and would help both Ontario and Canada meet air pollution reduction commitments under international agreements. It was noted that phasing out coal-fired power plants by one-third will help Ontario achieve its goal of a 90 per cent reduction in mercury emissions by 2010. It was suggested that alternative power sources can offer a wide range of environmental advantages. 16 refs., 3 tabs., 2 figs

  4. Mercury(II) and methyl mercury speciation on Streptococcus pyogenes loaded Dowex Optipore SD-2

    Energy Technology Data Exchange (ETDEWEB)

    Tuzen, Mustafa, E-mail: m.tuzen@gmail.com [Gaziosmanpasa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Uluozlu, Ozgur Dogan [Gaziosmanpasa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Karaman, Isa [Gaziosmanpasa University, Faculty of Science and Arts, Biology Department, 60250 Tokat (Turkey); Soylak, Mustafa [Erciyes University, Faculty of Science and Arts, Chemistry Department, 38039 Kayseri (Turkey)

    2009-09-30

    A solid phase extraction procedure based on speciation of mercury(II) and methyl mercury on Streptococcus pyogenes immobilized on Dowex Optipore SD-2 has been established. Selective and sequential elution with 0.1 mol L{sup -1} HCl for methyl mercury and 2 mol L{sup -1} HCl for mercury(II) were performed at pH 8. The determination of mercury levels was performed by cold vapour atomic absorption spectrometry (CVAAS). Optimal analytical conditions including pH, amounts of biosorbent, sample volumes, etc., were investigated. The influences of the some alkaline and earth alkaline ions and some transition metals on the recoveries were also investigated. The capacity of biosorbent for mercury(II) and methyl mercury was 4.8 and 3.4 mg g{sup -1}. The detection limit (3 sigma) of the reagent blank for mercury(II) and methyl mercury was 2.1 and 1.5 ng L{sup -1}. Preconcentration factor was calculated as 25. The relative standard deviations of the procedure were below 7%. The validation of the presented procedure is performed by the analysis of standard reference material (NRCC-DORM 2 Dogfish Muscle). The procedure was successfully applied to the speciation of mercury(II) and methyl mercury in natural water and environmental samples.

  5. Mercury(II) and methyl mercury speciation on Streptococcus pyogenes loaded Dowex Optipore SD-2

    International Nuclear Information System (INIS)

    Tuzen, Mustafa; Uluozlu, Ozgur Dogan; Karaman, Isa; Soylak, Mustafa

    2009-01-01

    A solid phase extraction procedure based on speciation of mercury(II) and methyl mercury on Streptococcus pyogenes immobilized on Dowex Optipore SD-2 has been established. Selective and sequential elution with 0.1 mol L -1 HCl for methyl mercury and 2 mol L -1 HCl for mercury(II) were performed at pH 8. The determination of mercury levels was performed by cold vapour atomic absorption spectrometry (CVAAS). Optimal analytical conditions including pH, amounts of biosorbent, sample volumes, etc., were investigated. The influences of the some alkaline and earth alkaline ions and some transition metals on the recoveries were also investigated. The capacity of biosorbent for mercury(II) and methyl mercury was 4.8 and 3.4 mg g -1 . The detection limit (3 sigma) of the reagent blank for mercury(II) and methyl mercury was 2.1 and 1.5 ng L -1 . Preconcentration factor was calculated as 25. The relative standard deviations of the procedure were below 7%. The validation of the presented procedure is performed by the analysis of standard reference material (NRCC-DORM 2 Dogfish Muscle). The procedure was successfully applied to the speciation of mercury(II) and methyl mercury in natural water and environmental samples.

  6. Spallation neutron source target station design, development, and commissioning

    International Nuclear Information System (INIS)

    Haines, J.R.; McManamy, T.J.; Gabriel, T.A.; Battle, R.E.; Chipley, K.K.; Crabtree, J.A.; Jacobs, L.L.; Lousteau, D.C.; Rennich, M.J.; Riemer, B.W.

    2014-01-01

    The spallation neutron source target station is designed to safely, reliably, and efficiently convert a 1 GeV beam of protons to a high flux of about 1 meV neutrons that are available at 24 neutron scattering instrument beam lines. Research and development findings, design requirements, design description, initial checkout testing, and results from early operation with beam are discussed for each of the primary target subsystems, including the mercury target, neutron moderators and reflector, surrounding vessels and shielding, utilities, remote handling equipment, and instrumentation and controls. Future plans for the mercury target development program are also briefly discussed

  7. Sexual differences in the excretion of organic and inorganic mercury by methyl mercury-treated rats

    International Nuclear Information System (INIS)

    Thomas, D.J.; Fisher, H.L.; Sumler, M.R.; Mushak, P.; Hall, L.L.

    1987-01-01

    Adult male and female Long Evans rats received 1 mumole of methyl ( 203 Hg) mercuric chloride per kilogram sc. Whole-body retention of mercury and excretion of organic and inorganic mercury in urine and feces were monitored for 98 days after dosing. Females cleared mercury from the body more rapidly than did males. The major route of mercury excretion was feces. By 98 days after dosing, cumulative mercury excretion in feces accounted for about 51% of the dose in males and about 54% of the dose in females. For both sexes, about 33% of the dose was excreted in feces as inorganic mercury. Cumulative excretion of organic mercury in feces accounted for about 18 and 21% of the dose in males and females, respectively. Urinary excretion of mercury was quantitatively a smaller route for mercury clearance but important sexual differences in loss by this route were found. Over the 98-day experimental period, males excreted in urine about 3.2% of the dose and females excreted 7.5%. Cumulative organic Hg excretion in urine accounted for 1.8% of the dose in males and 5.3% of the dose in females. These sexual differences in urinary and fecal excretion of organic and inorganic mercury following methyl mercury treatment were consistent with previous reports of sexual differences in mercury distribution and retention in methyl mercury-treated rats, particularly sexual differences in organic mercury uptake and retention in the kidney. Relationships between body burdens of organic or inorganic Hg and output of these forms of Hg in urine and feces were also found to be influenced by the interval after MeHg treatment and by sex. Relationship between concentration of Hg in liver and feces and in kidney and urine differed for organic and inorganic Hg and depended upon sexual status and interval after MeHg treatment

  8. Mercury Exposure Assessment and Spatial Distribution in A Ghanaian Small-Scale Gold Mining Community

    Directory of Open Access Journals (Sweden)

    Mozhgon Rajaee

    2015-09-01

    Full Text Available Mercury is utilized worldwide in artisanal and small-scale gold mining (ASGM and may pose a risk for miners and mining communities. While a number of studies have characterized mercury in ASGM communities, most have focused on a single media and few have taken a holistic approach. Here, a multiple media exposure assessment and cross-sectional study of mercury was conducted in 2010 through 2012 in northeast Ghana with a small-scale gold mining community, Kejetia, a subsistence farming community, Gorogo, and an urban ASGM gold refinery in Bolgatanga. The objective was to assess mercury in a range of human (urine and hair and ecological (household soil, sediment, fish, and ore samples to increase understanding of mercury exposure pathways. All participants were interviewed on demographics, occupational and medical histories, and household characteristics. Participants included 90 women of childbearing age and 97 adults from Kejetia and 75 adults from Gorogo. Median total specific gravity-adjusted urinary, hair, and household soil mercury were significantly higher in Kejetia miners (5.18 µg/L, 0.967 µg/g, and 3.77 µg/g, respectively than Kejetia non-miners (1.18 µg/L, 0.419 µg/g, and 2.00 µg/g, respectively and Gorogo participants (0.154 µg/L, 0.181 µg/g, and 0.039 µg/g in 2011. Sediment, fish, and ore Hg concentrations were below guideline values. Median soil mercury from the Bolgatanga refinery was very high (54.6 µg/g. Estimated mean mercury ingestion for Kejetia adults from soil and dust exceeded the U.S. Environmental Protection Agency reference dose (0.3 µg Hg/kg·day for pica (0.409 µg Hg/kg·day and geophagy (20.5 µg Hg/kg·day scenarios. Most participants with elevated urinary and household soil mercury were miners, but some non-miners approached and exceeded guideline values, suggesting a health risk for non-mining residents living within these communities.

  9. Field Induced Magnetic Moments in a Metastable Iron-Mercury Alloy

    DEFF Research Database (Denmark)

    Pedersen, M.S.; Mørup, Steen; Linderoth, Søren

    1996-01-01

    The magnetic properties of a metastable iron-mercury alloy have been investigated in the temperature range from 5 to 200 K by Mossbauer spectroscopy and magnetization measurements. At low temperature the magnetic moment per iron atom is larger than af alpha-Fe. The effective spontaneous magnetic ....... It was found that the field-induced increase of the magnetic moment in the metastable iron-mecury alloy was about 0.06 Bohr magnetons per iron atom in the temperature range from 5 to 200 K for a field change from 6 to 12 T....

  10. Safety concept for spallation target system. JAERI/KEK joint project

    International Nuclear Information System (INIS)

    Kobayashi, K.; Kaminaga, M.; Haga, K.; Kinoshita, H.; Hino, R.

    2001-01-01

    A MW-class mercury target of the spallation target generates much larger amounts of radioactive nuclides than existing spallation neutron sources. To estimate the maximum level of public exposure under the guillotine break of mercury pipelines that is one of the major accidents of the target system, the hazard analyses were carried out by using a transportation model which considers heat transmission of mercury decay heat, diffusion of evaporated radioactive nuclides, etc. In the analyses, mercury, iodine, bromine and noble gas were selected as the effective source term because of their high vapor pressures and activation levels. From the preliminary analytical results obtained under the conservative conditions of 2 m/s of the air velocity around the mercury leakage area, the maximum level of the public exposure was approximately 5.8 x 10 -3 mSv. This level is negligible in comparison with 1 mSV one-year natural radiation exposure. (author)

  11. Increased Mercury Bioaccumulation Follows Water Quality Improvement

    Energy Technology Data Exchange (ETDEWEB)

    Bogle, M.A.; Peterson, M.J.; Smith, J.G.; Southworth, G.R.

    1999-09-15

    Changes in physical and chemical characteristics of aquatic habitats made to reduce or eliminate ecological risks can sometimes have unforeseen consequences. Environmental management activities on the U.S. Dept. of Energy reservation in Oak Ridge, Tennessee,have succeeded in improving water quality in streams impacted by discharges fi-om industrial facilities and waste disposal sites. The diversity and abundance of pollution-sensitive components of the benthic macroinvertebrate communities of three streams improved after new waste treatment systems or remedial actions reduced inputs of various toxic chemicals. Two of the streams were known to be mercury-contaminated from historical spills and waste disposal practices. Waterborne mercury concentrations in the third were typical of uncontaminated systems. In each case, concentrations of mercury in fish, or the apparent biological availability of mercury increased over the period during which ecological metrics indicated improved water quality. In the system where waterborne mercury concentrations were at background levels, increased mercury bioaccumulation was probably a result of reduced aqueous selenium concentrations; however, the mechanisms for increased mercury accumulation in the other two streams remain under investigation. In each of the three systems, reduced inputs of metals and inorganic anions was followed by improvements in the health of aquatic invertebrate communities. However, this reduction in risk to aquatic invertebrates was accompanied by increased risk to humans and piscivorous wildlife related to increased mercury concentrations in fish.

  12. Increased Mercury Bioaccumulation Follows Water Quality Improvement

    International Nuclear Information System (INIS)

    Bogle, M.A.; Peterson, M.J.; Smith, J.G.; Southworth, G.R.

    1999-01-01

    Changes in physical and chemical characteristics of aquatic habitats made to reduce or eliminate ecological risks can sometimes have unforeseen consequences. Environmental management activities on the U.S. Dept. of Energy reservation in Oak Ridge, Tennessee,have succeeded in improving water quality in streams impacted by discharges fi-om industrial facilities and waste disposal sites. The diversity and abundance of pollution-sensitive components of the benthic macroinvertebrate communities of three streams improved after new waste treatment systems or remedial actions reduced inputs of various toxic chemicals. Two of the streams were known to be mercury-contaminated from historical spills and waste disposal practices. Waterborne mercury concentrations in the third were typical of uncontaminated systems. In each case, concentrations of mercury in fish, or the apparent biological availability of mercury increased over the period during which ecological metrics indicated improved water quality. In the system where waterborne mercury concentrations were at background levels, increased mercury bioaccumulation was probably a result of reduced aqueous selenium concentrations; however, the mechanisms for increased mercury accumulation in the other two streams remain under investigation. In each of the three systems, reduced inputs of metals and inorganic anions was followed by improvements in the health of aquatic invertebrate communities. However, this reduction in risk to aquatic invertebrates was accompanied by increased risk to humans and piscivorous wildlife related to increased mercury concentrations in fish

  13. A Challenging Case of Acute Mercury Toxicity

    Directory of Open Access Journals (Sweden)

    Ali Nayfeh

    2018-01-01

    Full Text Available Background. Mercury exists in multiple forms: elemental, organic, and inorganic. Its toxic manifestations depend on the type and magnitude of exposure. The role of colonoscopic decompression in acute mercury toxicity is still unclear. We present a case of acute elemental mercury toxicity secondary to mercury ingestion, which markedly improved with colonoscopic decompression. Clinical Case. A 54-year-old male presented to the ED five days after ingesting five ounces (148 cubic centimeters of elemental mercury. Examination was only significant for a distended abdomen. Labs showed elevated serum and urine mercury levels. An abdominal radiograph showed radiopaque material throughout the colon. Succimer and laxatives were initiated. The patient had recurrent bowel movements, and serial radiographs showed interval decrease of mercury in the descending colon with interval increase in the cecum and ascending colon. Colonoscopic decompression was done successfully. The colon was evacuated, and a repeat radiograph showed decreased hyperdense material in the colon. Three months later, a repeat radiograph showed no hyperdense material in the colon. Conclusion. Ingested elemental mercury can be retained in the colon. Although there are no established guidelines for colonoscopic decompression, our patient showed significant improvement. We believe further studies on this subject are needed to guide management practices.

  14. The influence of floodplains on mercury availability

    Energy Technology Data Exchange (ETDEWEB)

    Wallschlaeger, D.; Wilken, R.D. [GKSS Research Center, Geesthacht (Germany). Inst. of Physical and Chemical Analytics

    1997-09-01

    The floodplains of the German river Elbe affect the mercury distribution in the river system in two different ways: they act both as a medium-term sink and as a long-term source. The large amounts of mercury deposited onto the floodplains during annual floodings are first effectively fixed in the soils, rendering them basically unavailable. Sequential extraction experiments reveal that only a small fraction of the mercury (< 3%) is present in available forms, whereas the vast majority is associated with humic substances or present in sulfidic binding forms. After deposition, a small fraction of the total mercury is gradually remobilized into the aqueous phase bound passively to water-soluble humic acids. The availability of mercury in these complexes is still low, since environmental influences such as changes in pH or redox potential and competition with other cations do not cause any mercury liberation. In the next step, reactions in the aqueous phase lead to the formation of the highly available volatile species Hg{sup 0} and dimethylmercury (DMM). Their evaporation gives rise to a strong mercury flux from the floodplains into the atmosphere. Preliminary mass balances indicate that the majority of the deposited mercury stays bound in the floodplain soils, while small amounts are emitted back into the river`s ecosystem. Atmospheric emission is more important as a remobilization pathway than aquatic export.

  15. OCCURENCE OF MERCURY IN PET FOOD

    Directory of Open Access Journals (Sweden)

    M.C. Abete

    2013-02-01

    Full Text Available Mercury levels in 61 complete pet feed containing fish were evaluated. In five samples a mercury content exceeding the maximum residues level (0.4 mg/kg was detected. The statistical evaluation didn’t show a significant correlation between the percentage of fish in feedingstuffs and the contamination level.

  16. Hair mercury measurement in Egyptian autistic children

    African Journals Online (AJOL)

    Farida El-baz

    Abstract Background: A review of medical literature has shown that exposure to mercury, whether organic or inorganic, can give rise to the symptoms and traits defining or commonly found in autism spectrum disorders (ASD). Mercury can cause impairments in social interaction, commu- nication difficulties, and repetitive ...

  17. Terahertz oscillations in mercury cuprate superconductors

    Indian Academy of Sciences (India)

    Abstract. It has been recently reported that the three-dimensional Bose–Einstein con- densation of the quasi-particles is valid for the mercury cuprates at liquid helium tem- perature. In this study, the validity of the interlayer theory in three dimensions has been investigated for optimally oxygen-doped mercury cuprates at the ...

  18. Mercury poisoning | Shamley | South African Medical Journal

    African Journals Online (AJOL)

    The diagnosis of mercury poisoning requires a high index of suspicion. Mercury poisoning in a patient involved in illicit gold extraction is reported and 6 other cases considered. Some of the clinical features and treatment of this condition are discussed. S Afr Med J 1989; 76: 114-116 ...

  19. Mercury soil surveys: a good reconnaissance tool

    Energy Technology Data Exchange (ETDEWEB)

    Stone, C.; Ruscetta, C.A.; Foley, D. (eds.)

    1981-05-01

    Three examples of mercury soil surveys are discussed, along with the gravity data. An excellent correlation was found in southern Arizona between buried structures revealed by gravity and mercury soil surveys. The advantages of the latter over the former as a reconnaissance tool are listed. (MHR)

  20. Intentional intravenous mercury injection | Yudelowitz | South African ...

    African Journals Online (AJOL)

    Intravenous mercury injection is rarely seen, with few documented cases. Treatment strategies are not clearly defined for such cases, although a few options do show benefit. This case report describes a 29-year-old man suffering from bipolar disorder, who presented following self-inflicted intravenous injection of mercury.

  1. Pneumonitis after Inhalation of Mercury Vapours

    Directory of Open Access Journals (Sweden)

    JD Glezos

    2006-01-01

    Full Text Available A 43-year-old man presented to hospital with pneumonia but only after discharge from hospital did he admit to deliberate prior inhalation of mercury. His pulmonary involvement appeared to resolve almost completely with antibiotics and supportive care. Nevertheless, persisting elevated urinary excretion of mercury required two courses of chelation therapy. No serious systemic sequelae were observed.

  2. Recent Advances in Atmospheric Chemistry of Mercury

    Directory of Open Access Journals (Sweden)

    Lin Si

    2018-02-01

    Full Text Available Mercury is one of the most toxic metals and has global importance due to the biomagnification and bioaccumulation of organomercury via the aquatic food web. The physical and chemical transformations of various mercury species in the atmosphere strongly influence their composition, phase, transport characteristics and deposition rate back to the ground. Modeling efforts to assess global cycling of mercury require an accurate understanding of atmospheric mercury chemistry. Yet, there are several key uncertainties precluding accurate modeling of physical and chemical transformations. We focus this article on recent studies (since 2015 on improving our understanding of the atmospheric chemistry of mercury. We discuss recent advances in determining the dominant atmospheric oxidant of elemental mercury (Hg0 and understanding the oxidation reactions of Hg0 by halogen atoms and by nitrate radical (NO3—in the aqueous reduction of oxidized mercury compounds (HgII as well as in the heterogeneous reactions of Hg on atmospheric-relevant surfaces. The need for future research to improve understanding of the fate and transformation of mercury in the atmosphere is also discussed.

  3. Urban artisanal gold shops and mercury emissions

    International Nuclear Information System (INIS)

    Cordy, P.; Veiga, M.; Carrasco, V.H.G.

    2008-01-01

    Artisanal miners in developing countries use mercury amalgamation processes to extract gold. The amalgams are then refined before being sold on to urban gold shops. The amalgams can often contain between 2 to 40 per cent mercury. Unburned amalgams are also often sold directly to gold shops. There are serious health risks for shop employees and nearby populations when the gold is melted and further purified. Studies have shown that mercury concentrations in the ambient air of gold shops often exceeds World Health Organization (WHO) limits by an order of magnitude or more. This study examined the practices and technologies used to refine gold in Latin America and Indonesia. The study compared and contrasted various refining methods and their resulting mercury emissions. Methods of reducing mercury emissions were also investigated, including a filtration system designed to capture 80 per cent of mercury emissions. Barriers to implementing mercury emissions reduction plans were also investigated. It was concluded that the design of urban gold shops must include condensers, fume hoods, and efficient mercury capture systems. 15 refs

  4. Mercury cycling in peatland watersheds. Chapter 11.

    Science.gov (United States)

    Randall K. Kolka; Carl P.J. Mitchell; Jeffrey D. Jeremiason; Neal A. Hines; David F. Grigal; Daniel R. Engstrom; Jill K. Coleman-Wasik; Edward A. Nater; Edward B. Swain; Bruce A. Monson; Jacob A. Fleck; Brian Johnson; James E. Almendinger; Brian A. Branfireun; Patrick L. Brezonik; James B. Cotner

    2011-01-01

    Mercury (Hg) is of great environmental concern due to its transformation into the toxic methylmercury (MeHg) form that bioaccumulates within the food chain and causes health concerns for both humans and wildlife (U.S. Environmental Protection Agency 2002). Mercury can affect neurological development in fetuses and young children. In adults, exposure to Hg can lead to...

  5. Mercury in tropical and subtropical coastal environments

    Science.gov (United States)

    Costa, Monica F.; Landing, William M.; Kehrig, Helena A.; Barletta, Mário; Holmes, Christopher D.; Barrocas, Paulo R. G.; Evers, David C.; Buck, David G.; Vasconcellos, Ana Claudia; Hacon, Sandra S.; Moreira, Josino C.; Malm, Olaf

    2012-01-01

    Anthropogenic activities influence the biogeochemical cycles of mercury, both qualitatively and quantitatively, on a global scale from sources to sinks. Anthropogenic processes that alter the temporal and spatial patterns of sources and cycling processes are changing the impacts of mercury contamination on aquatic biota and humans. Human exposure to mercury is dominated by the consumption of fish and products from aquaculture operations. The risk to society and to ecosystems from mercury contamination is growing, and it is important to monitor these expanding risks. However, the extent and manner to which anthropogenic activities will alter mercury sources and biogeochemical cycling in tropical and sub-tropical coastal environments is poorly understood. Factors as (1) lack of reliable local/regional data; (2) rapidly changing environmental conditions; (3) governmental priorities and; (4) technical actions from supra-national institutions, are some of the obstacles to overcome in mercury cycling research and policy formulation. In the tropics and sub-tropics, research on mercury in the environment is moving from an exploratory “inventory” phase towards more process-oriented studies. Addressing biodiversity conservation and human health issues related to mercury contamination of river basins and tropical coastal environments are an integral part of paragraph 221 paragraph of the United Nations document “The Future We Want” issued in Rio de Janeiro in June 2012. PMID:22901765

  6. Episodic bioavailability of environmental mercury: implications for ...

    African Journals Online (AJOL)

    Perennial wildfires in Africa and other continents contribute an estimated 8 x 105 kg of mercury to the global atmosphere with a residence time of approximately one year. This phenomenon changes the flux of biologically available mercury in natural microbial communities where enzymatic actions, including mercuric ...

  7. Terahertz oscillations in mercury cuprate superconductors

    Indian Academy of Sciences (India)

    It has been recently reported that the three-dimensional Bose–Einstein condensation of the quasi-particles is valid for the mercury cuprates at liquid helium temperature. In this study, the validity of the interlayer theory in three dimensions has been investigated for optimally oxygen-doped mercury cuprates at the temperature ...

  8. Mercury in Thana creek, Bombay harbour

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Desai, B.N.

    Mercury content of the water column estimated along Thana Creek/Bombay Harbour gave a standing stock of about 77 kg in excess of the expected background. Mercury concentration in sediment from 23 locations which varied from 0.17 to 8.21 ppm (dry...

  9. Urban artisanal gold shops and mercury emissions

    Energy Technology Data Exchange (ETDEWEB)

    Cordy, P.; Veiga, M.; Carrasco, V.H.G. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Mining and Mineral Process Engineering

    2008-07-01

    Artisanal miners in developing countries use mercury amalgamation processes to extract gold. The amalgams are then refined before being sold on to urban gold shops. The amalgams can often contain between 2 to 40 per cent mercury. Unburned amalgams are also often sold directly to gold shops. There are serious health risks for shop employees and nearby populations when the gold is melted and further purified. Studies have shown that mercury concentrations in the ambient air of gold shops often exceeds World Health Organization (WHO) limits by an order of magnitude or more. This study examined the practices and technologies used to refine gold in Latin America and Indonesia. The study compared and contrasted various refining methods and their resulting mercury emissions. Methods of reducing mercury emissions were also investigated, including a filtration system designed to capture 80 per cent of mercury emissions. Barriers to implementing mercury emissions reduction plans were also investigated. It was concluded that the design of urban gold shops must include condensers, fume hoods, and efficient mercury capture systems. 15 refs.

  10. Mercury Sorption onto Malt Spent Rootlets

    Science.gov (United States)

    Manariotis, I. D.; Anagnostopoulos, V.; Karapanagioti, H. K.; Chrysikopoulos, C.

    2011-12-01

    Mercury is a metal of particular concern due to its toxicity even at relatively low concentrations. The maximum permissible level for mercury in drinking water set by the European Union is 0.001 mg/L. Mercury is released into the environment via four principal pathways: (1) natural processes; i.e. a volcanic eruption, (2) incidental to some other activity; i.e. coal burning power plants, (3) accidentally during the manufacture, breakage or disposal of products that have mercury put into them deliberately, and (4) direct use in industrial settings. The present study focuses on the removal of mercury (II) from aqueous solutions via sorption onto Malt Spent Rootlets (MSR). Batch experiments were conducted employing MSR with size ranging from 0.18 to 1 mm. The effects of pH, mercury concentration, contact time, and solid to liquid ratio on mercury sorption onto MSR were investigated. The highest mercury removal from the aqueous phase, of 41%, was observed at pH of 5.

  11. The extent of the influence and flux estimation of volatile mercury from the aeration pool in a typical coal-fired power plant equipped with a seawater flue gas desulfurization system

    International Nuclear Information System (INIS)

    Sun, Lumin; Feng, Lifeng; Yuan, Dongxing; Lin, Shanshan; Huang, Shuyuan; Gao, Liangming; Zhu, Yong

    2013-01-01

    Before being discharged, the waste seawater from the flue gas desulfurization system of coal-fired power plants contains a large amount of mercury, and is treated in aeration pools. During this aeration process, part of the mercury enters the atmosphere, but only very limited impact studies concerning this have been carried out. Taking a typical Xiamen power plant as an example, the present study targeted the elemental mercury emitted from the aeration pool. Concentrations of dissolved gaseous mercury as high as 1.14 ± 0.17 ng·L −1 were observed in the surface waste seawater in the aeration pool, and gaseous elemental mercury (GEM) as high as 10.94 ± 1.89 ng·m −3 was found in the air above the pool. To investigate the area affected by this GEM through air transfer, the total mercury in the dust and topsoil samples around the aeration pool were analyzed. Much higher values were found compared to those at a reference site. Environmental factors other than solar radiation had limited influence on the concentrations of the mercury species in the pool. A simulation device was built in our laboratory to study the flux of mercury from the aeration pool into the air. The results showed that more than 0.59 kg of mercury was released from the aeration pool every year, occupying 0.3% of the total mercury in the waste seawater. The transfer of mercury from water to air during the aeration pool and its environmental influence should not be ignored. - Highlights: ► High concentration of volatile mercury was observed in the aeration pool. ► More than 0.3% of total discharged Hg emitted from the pool into the air. ► Higher aeration rate resulted in more mercury emitted into the air. ► The dust and topsoil around the pool were polluted with the mercury

  12. Low dose mercury toxicity and human health.

    Science.gov (United States)

    Zahir, Farhana; Rizwi, Shamim J; Haq, Soghra K; Khan, Rizwan H

    2005-09-01

    Post Minamata incident there has been awareness about mercury toxicity even among the general public. Previous researches contributed a vast amount of data regarding acute mercury exposure, but gradually information about the low dose [Ninomiya, T., Ohmori, H., Hashimoto, K., Tsuruta, K., Ekino, S., 1995. Expansion of methylmercury poisoning outside minamata: an epidemiological study on chronic methylmercury poisoninig outside of Minamata. Environ. Res. 70 (1) 47-50; Lebel, J., Mergler, D., Lucotte, M., Amorim, M., Dolbec, J., Miranda, D., Arantes, G., Rheault, I., Pichet, P., 1996. Evidence of early nervous system dysfunction in Amazonian populations exposed to low-levels of methylmercury. Neurotoxicology 17 (1) 157-167] of mercury toxicity has been trickling in. With mercury contaminating rain-, ground- and sea-water no one is safe. Polluted water leads to mercury laced fish, meat and vegetable. In aquatic environments, inorganic mercury is microbiologically transformed into lipophilic organic compound 'methylmercury'. This transformation makes mercury more prone to biomagnification in food chains. Consequently, populations with traditionally high dietary intake of food originating from fresh or marine environment have highest dietary exposure to mercury. Extensive research done on locals across the globe have already established this, persons who routinely consume fish or a particular species of fish are at an increased risk of methylmercury poisoning. The easy access of the toxicant to man through multiple pathways air, water, food, cosmetic products and even vaccines increase the exposure. Foetus and children are more susceptible towards mercury toxicity. Mothers consuming diet containing mercury pass the toxicant to foetus and to infants through breast milk. Decreased performance in areas of motor function and memory has been reported among children exposed to presumably safe mercury levels. Similarly, disruption of attention, fine motor function and verbal

  13. Effect of salinity on methylation of mercury

    Energy Technology Data Exchange (ETDEWEB)

    Blum, J.E.; Bartha, R.

    1980-09-01

    Monomethyl and dimethylmercury are potent neurotoxins subject to biomagnification in food webs. This fact was tragically demonstrated by the Minamata and Niigata poisoning incidents in Japan in which 168 persons who ate seafood from mercury polluted waters were poisoned, 52 fatally. Shortly after these two incidents, work conducted in freshwater environments demonstrated the microbial conversion of inorganic and phenylmercury compounds to mono- and di-methylmercury. Consideration of some fragmentary evidence from the literature, however, indicates that the rate and the significance of microbial methylation of mercury in freshwater and saltwater environments may not be the same. A demonstrated relationship between mercury methylation rates and water salinity would greatly influence our thinking about mercury pollution effects in marine versus freshwater environments. Since we were unable to locate published reports on this subject, we are investigating the influence of salinity on the rate of mercury methylation in an estuarine sediment.

  14. High activity carbon sorbents for mercury capture

    Directory of Open Access Journals (Sweden)

    Stavropoulos George G.

    2006-01-01

    Full Text Available High efficiency activated carbons have been prepared for removing mercury from gas streams. Starting materials used were petroleum coke, lignite, charcoal and olive seed waste, and were chemically activated with KOH. Produced adsorbents were primarily characterized for their porosity by N2 adsorption at 77 K. Their mercury retention capacity was characterized based on the breakthrough curves. Compared with typical commercial carbons, they have exhibited considerably enhanced mercury adsorption capacity. An attempt has been made to correlate mercury entrapment and pore structure. It has been shown that physical surface area is increased during activation in contrast to the mercury adsorption capacity that initially increases and tends to decrease at latter stages. Desorption of active sites may be responsible for this behavior.

  15. Human accumulation of mercury in Greenland

    DEFF Research Database (Denmark)

    Johansen, Poul; Mulvad, Gert; Pedersen, Henning Sloth

    2007-01-01

    In the Arctic, the traditional diet exposes its people to a high intake of mercury especially from marine mammals. To determine whether the mercury is accumulated in humans, we analyzed autopsy samples of liver, kidney and spleen from adult ethnic Greenlanders who died between 1990 and 1994 from...... a wide range of causes, natural and violent. Liver, kidney and spleen samples from between 33 and 71 case subjects were analyzed for total mercury and methylmercury, and liver samples also for selenium. Metal levels in men and women did not differ and were not related to age except in one case, i...... in liver and spleen and as little as 3% in kidney. In liver selenium was found in surplus to mercury on a molar basis. Mercury concentrations in the liver and kidneys of Greenlanders were elevated compared to levels in the general population in Japan, Korea and several European countries, except...

  16. Autism: a novel form of mercury poisoning.

    Science.gov (United States)

    Bernard, S; Enayati, A; Redwood, L; Roger, H; Binstock, T

    2001-04-01

    Autism is a syndrome characterized by impairments in social relatedness and communication, repetitive behaviors, abnormal movements, and sensory dysfunction. Recent epidemiological studies suggest that autism may affect 1 in 150 US children. Exposure to mercury can cause immune, sensory, neurological, motor, and behavioral dysfunctions similar to traits defining or associated with autism, and the similarities extend to neuroanatomy, neurotransmitters, and biochemistry. Thimerosal, a preservative added to many vaccines, has become a major source of mercury in children who, within their first two years, may have received a quantity of mercury that exceeds safety guidelines. A review of medical literature and US government data suggests that: (i) many cases of idiopathic autism are induced by early mercury exposure from thimerosal; (ii) this type of autism represents an unrecognized mercurial syndrome; and (iii) genetic and non-genetic factors establish a predisposition whereby thimerosal's adverse effects occur only in some children. Copyright 2001 Harcourt Publishers Ltd.

  17. Removal of mercury by adsorption: a review.

    Science.gov (United States)

    Yu, Jin-Gang; Yue, Bao-Yu; Wu, Xiong-Wei; Liu, Qi; Jiao, Fei-Peng; Jiang, Xin-Yu; Chen, Xiao-Qing

    2016-03-01

    Due to natural and production activities, mercury contamination has become one of the major environmental problems over the world. Mercury contamination is a serious threat to human health. Among the existing technologies available for mercury pollution control, the adsorption process can get excellent separation effects and has been further studied. This review is attempted to cover a wide range of adsorbents that were developed for the removal of mercury from the year 2011. Various adsorbents, including the latest adsorbents, are presented along with highlighting and discussing the key advancements on their preparation, modification technologies, and strategies. By comparing their adsorption capacities, it is evident from the literature survey that some adsorbents have shown excellent potential for the removal of mercury. However, there is still a need to develop novel, efficient adsorbents with low cost, high stability, and easy production and manufacture for practical utility.

  18. Speciation of mercury in water and fish samples by HPLC-ICP-MS after magnetic solid phase extraction.

    Science.gov (United States)

    Zhu, Siqi; Chen, Beibei; He, Man; Huang, Tong; Hu, Bin

    2017-08-15

    In this paper, Fe 3 O 4 @SiO 2 @γ-mercaptopropyltrimethoxysilane (γ-MPTS) magnetic nanoparticles was prepared and a new method of magnetic solid phase extraction (MSPE)-high performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry (ICP-MS) was developed for the speciation of mercury including inorganic mercury (Hg 2+ ), methylmercury (MeHg + ) and phenylmercury (PhHg + ) in environmental water, wastewater, tap water and fish samples. A rapid separation of three target mercury species was achieved in 8min by employing relatively high ratio of methanol in HPLC mobile phase. Various parameters affecting Fe 3 O 4 @SiO 2 @γ-MPTS-based MSPE of target mercury species have been investigated. Under the optimized conditions, the limits of detection for Hg 2+ , MeHg + and PhHg + were in the range of 0.49-0.74ngL -1 . The intra- and inter-day relative standard deviations (n=5) were less than 9.0% and 12%, respectively. The developed MSPE-HPLC-ICP-MS method was validated by the speciation of mercury in the Certified Reference Material of DORM-2 dogfish as well as real-world samples including environmental water, wastewater, tap water and fish samples, and it has the advantages of simple operation, rapid separation, high sensitivity, high enrichment factor and is suitable for the analysis of mercury species in samples with complex matrix. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. 21 CFR 862.3600 - Mercury test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mercury test system. 862.3600 Section 862.3600....3600 Mercury test system. (a) Identification. A mercury test system is a device intended to measure mercury, a heavy metal, in human specimens. Measurements obtained by this device are used in the diagnosis...

  20. 21 CFR 880.2920 - Clinical mercury thermometer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Clinical mercury thermometer. 880.2920 Section 880... Devices § 880.2920 Clinical mercury thermometer. (a) Identification. A clinical mercury thermometer is a... mercury. (b) Classification. Class II (special controls). The device is exempt from the premarket...

  1. Mercury contamination in chile: a chronicle of a problem foretold.

    Science.gov (United States)

    Barrios-Guerra, Carlos A

    2004-01-01

    This review analyzes the effects of environmental mercury contamination in Chile. This contamination generates one of the most important environmental conflicts in the country in that it affects air, ground, and water (rivers and oceans), which are fundamental in maintaining natural biotic equilibrium and at the same time important for the nation's economy. Chile possesses extraordinarily wealthy mining resources between Regions I and IV that have developed into an extraction industry essential for the economy of the country. However, waste discharges from this production have created an environmental problem in that the majority of the mines are located in the Andes mountain range, or areas close by, and the water used in the extraction process is deposited into the rivers, significantly increasing the amount of chemical contamination. Therefore, the cities and downstream waters used in agriculture suffer the negative consequences of a natural resource that is becoming more and more scarce. In addition, minerals released from mills into the atmosphere are deposited onto the soil, drastically affecting the biological resources of these areas. One of these affected areas is the Metropolitan region, where one of the highest contamination levels of mercury in the country was found in one of its affluents due to industrial and domestic waste discharge. In a country that is only 200 km in width, the gathering of all these contaminants in the rivers results in a rapid flow to the ocean, thereby contaminating coastal waters and the biota. In general, this contamination has been detected in semiclosed bodies of water (bays). Between Regions VII and IX, the principal sources of mercury contamination are related to cellulose industrial sites (Regions VII and VIII) and, until the 1980s, the bleach-soda industry. The most important industrial and fishing activity is also found in this area. In San Vicente Bay, waste discharges released into the ocean include sewage, industrial

  2. Biomolecular Aspects of Mercury Transformations

    Science.gov (United States)

    Johs, A.; Shi, L.; Miller, S. M.; Summers, A. O.; Liang, L.

    2008-12-01

    Bacteria participate significantly in mercury transformation in natural and industrial environments. Previous studies have shown that bacterial mercury resistance is mediated by the mer operon, typically located on transposons or plasmids. It encodes specific genes that facilitate uptake of mercury species, cleavage of organomercurials, and reduction of Hg(II) to Hg(0). Expression of mer operon genes is regulated by MerR, a metal-responsive regulator protein on the level of transcription. In vitro studies have shown that MerR forms a non-transcribing pre-initiation complex with RNA polymerase and the promoter DNA. Binding of Hg(II) induces conformational changes in MerR and other components of the complex resulting in the transcription of mer operon genes. As part of ongoing investigations on allosteric conformational changes induced by Hg(II) in dimeric MerR, and the implications on the binding of RNA polymerase to the promoter of the mer operon, we applied small angle scattering to study the regulatory mechanism of MerR in the presence and absence of Hg(II). Our results show that in the presence of Hg(II) the MerR dimer undergoes a significant reorientation from a compact state to a conformation revealing two distinct domains. Bacterial reduction of Hg(II) can also occur at concentrations too low to induce mer operon functions. Dissimilatory metal reducing bacteria, such as Shewanella and Geobacter are able to reduce Hg(II) in the presence of mineral oxides. This process has been linked to the activity of outer membrane multiheme cytochromes. We isolated and purified a decaheme outer membrane cytochrome OmcA from Shewanella oneidensis MR-1 and characterized its envelope shape in solution by small angle x-ray scattering. Structural features were identified and compared to homology models. These results show that OmcA is an elongated macromolecule consisting of separate modules, which may be connected by flexible linkers.

  3. Strangeness production at 200 GeV/Nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Jacak, B.V.

    1991-01-01

    Results from the HELIOS External Spectrometer on kaon production in 200 GeV/A S+W and p+W collisions are presented. The K/{pi} ratios are compared with measurements at lower bombarding energies and are found to agree remarkably well. Evidence for secondary production of K{sup +} by meson-baryon rescattering is reviewed. The target rapidity results are compared with neutral strange particle results at midrapidity. 15 refs., 4 figs., 2 tabs.

  4. Mercury in food items from the Idrija Mercury Mine area.

    Science.gov (United States)

    Miklavčič, Ana; Mazej, Darja; Jaćimović, Radojko; Dizdarevi, Tatjana; Horvat, Milena

    2013-08-01

    As a consequence of over 500 years of mining and smelting activities (1490-1995), and of its natural geological occurrence, the soil in the Idrija region is highly contaminated with Hg. In order to assess the present situation regarding the Hg levels in local food samples, concentrations of total mercury (THg) and monomethyl mercury (MeHg) were determined in selected vegetables, mushrooms and fish from the Idrija Hg mine area. Hg levels in the foodstuffs analysed were not very high but were elevated compared to the levels in food from non-contaminated areas. The study showed that THg accumulates in mushrooms (X=5680ng/g dry weight, Min=346ng/g dry weight, Max=17,100 dry weight) and chicory (X=1950ng/g dry weight, Min=86ng/g dry weight, Max=17,100ng/g dry weight). In addition, Se and Cd concentrations were determined by ICP-MS in those vegetable and mushroom species in which the highest Hg levels were found. The levels of Cd and Se were below the threshold levels. Based on data from previous studies, we can conclude that the levels of Hg in food have not diminished significantly during the past 15 years after closure of the Hg mine. Special attention should be given to vegetables such as chicory, representing a local seasonal vegetable eaten frequently. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Estimating mercury emissions from a zinc smelter in relation to China's mercury control policies

    International Nuclear Information System (INIS)

    Wang, S.X.; Song, J.X.; Li, G.H.; Wu, Y.; Zhang, L.; Wan, Q.; Streets, D.G.; Chin, Conrad K.; Hao, J.M.

    2010-01-01

    Mercury concentrations of flue gas at inlet/outlet of the flue gas cleaning, electrostatic demister, reclaiming tower, acid plant, and mercury contents in zinc concentrate and by-products were measured in a hydrometallurgical zinc smelter. The removal efficiency of flue gas cleaning, electrostatic demister, mercury reclaiming and acid plant was about 17.4%, 30.3%, 87.9% and 97.4% respectively. Flue gas cleaning and electrostatic demister captured 11.7% and 25.3% of the mercury in the zinc concentrate, respectively. The mercury reclaiming tower captured 58.3% of the mercury in the zinc concentrate. About 4.2% of the mercury in the zinc concentrate was captured by the acid plant. Consequently, only 0.8% of the mercury in the zinc concentrate was emitted to the atmosphere. The atmospheric mercury emission factor was 0.5 g t -1 of zinc produced for the tested smelter, indicating that this process offers the potential to effectively reduce mercury emissions from zinc smelting. - Modern scale production equipped with acid plant and Hg reclaiming tower will significantly reduce Hg emissions from zinc smelters in China.

  6. Treatment of mercury containing waste

    Science.gov (United States)

    Kalb, Paul D.; Melamed, Dan; Patel, Bhavesh R; Fuhrmann, Mark

    2002-01-01

    A process is provided for the treatment of mercury containing waste in a single reaction vessel which includes a) stabilizing the waste with sulfur polymer cement under an inert atmosphere to form a resulting mixture and b) encapsulating the resulting mixture by heating the mixture to form a molten product and casting the molten product as a monolithic final waste form. Additional sulfur polymer cement can be added in the encapsulation step if needed, and a stabilizing additive can be added in the process to improve the leaching properties of the waste form.

  7. Mercury migration into ground water, a literature study

    Energy Technology Data Exchange (ETDEWEB)

    Carlton, W.H.; Carden, J.L.; Kury, R.; Eichholz, G.G.

    1994-11-01

    This report presents a broad review of the technical literature dealing with mercury migration in the soil. The approach followed was to identify relevant articles by searching bibliographic data bases, obtaining the promising articles and searching these articles for any additional relevant citations. Eight catagories were used to organize the literature, with a review and summary of each paper. Catagories used were the following: chemical states of mercury under environmental conditions; diffusion of mercury vapor through soil; solubility and stability of mercury in environmental waters; transport of mercury on colloids; models for mercury migration through the environment; analytical techniques; retention of mercury by soil components; formation of organomecurials.

  8. Study of high levels indoor air mercury contamination from mercury amalgam use in dentistry

    International Nuclear Information System (INIS)

    Khwaja, M.A.; Abbasi, M.S.; Mehmood, F.; Jahangir, S.

    2014-01-01

    In 2005, United Nations Environment Programme (UNEP) estimated that 362 tonnes of dental mercury are consumed annually worldwide. Dental mercury amalgams also called silver fillings and amalgam fillings are widely done. These fillings gave off mercury vapours. Estimated average absorbed concentrations of mercury vapours from dental fillings vary from 3,000 to 17,000 ng Hg. Mercury (Hg) also known as quick silver is an essential constituent of dental amalgam. It is a toxic substance of global concern. A persistent pollutant, mercury is not limited to its source but it travels, on time thousands of kilometers away from the source. Scientific evidence, including, UNEP Global Mercury report, establishes mercury as an extremely toxic substance, which is a major threat to wildlife, ecosystem and human health, at a global scale. Children are more at risk from mercury poisoning which affects their neurological development and brain. Mercury poisoning diminishes memory, attention, thinking and sight. In the past, a number of studies at dental sites in many countries have been carried out and reported which have been reviewed and briefly described. This paper describes and discusses the recent investigations, regarding mercury vapours level in air, carried out at 18 dental sites in Pakistan and other countries. It is evident from the data of 42 dental sites in 17 countries, including, selected dental sites in five main cities of Pakistan, described and discussed in this paper that at most dental sites in many countries including Pakistan, the indoor mercury vapours levels exceed far above the permissible limit, recommended for safe physical and mental health. At these sites, public, in general, and the medical, paramedical staff and vulnerable population, in particular, are at most serious risk to health resulting from exposure to toxic and hazardous mercury. (author)

  9. Substance Flow Analysis of Mercury in China

    Science.gov (United States)

    Hui, L. M.; Wang, S.; Zhang, L.; Wang, F. Y.; Wu, Q. R.

    2015-12-01

    In previous studies, the emission of anthropogenic atmospheric Hg in China as well as single sector have been examined a lot. However, there might have been more Hg released as solid wastes rather than air. Hg stored in solid wastes may be released to air again when the solid wastes experience high temperature process or cause local pollution if the solid wastes are stacked casually for a long time. To trace the fate of Hg in China, this study developed the substance flow of Hg in 2010 covering all the sectors summarized in table 1. Below showed in Figure 1, the total Hg input is 2825t. The unintentional input of Hg, mined Hg, and recycled Hg account for 57%, 32% and 11% respectively. Figure 2 provides the detail information of substance flow of Hg. Byproducts from one sector may be used as raw materials of another, causing cross Hg flow between sectors. The Hg input of cement production is 303 t, of which 34% comes from coal and limestone, 33% comes from non-ferrous smelting, 23% comes from coal combustion, 7% comes from iron and steel production and 3% comes from mercury mining. Hg flowing to recycledHg production is 639 t, mainly from Hg contained in waste active carbon and mercuric chloride catalyst from VCM production and acid sludge from non-ferrous smelting. There are 20 t mercury flowing from spent mercury adding products to incineration. Figure1 and Figure 2 also show that 46% of the output Hg belongs to "Lagged release", which means this part of mercury might be released later. The "Lagged release" Hg includes 809 t Hg contained in stacked byproducts form coal combustion, non-ferrous smelting, iron and steel production, Al production, cement production and mercury mining, 161t Hg stored in the pipeline of VCM producing, 10 t Hg in fluorescent lamps that are in use and 314 t mercury stored in materials waiting to be handled with in recycled mercury plants. There is 112 t Hg stored in landfill and 129 t Hg exported abroad with the export of mercury adding

  10. Mercury in the environment : a primer

    Energy Technology Data Exchange (ETDEWEB)

    Lourie, B.; Glenn, W. (ed.); Ogilvie, K.; Everhardus, E.; Friesen, K.; Rae, S.

    2003-06-01

    This report provides an overview of the occurrence and effects of mercury in the environment and its impacts on human health. Low levels of mercury occur naturally everywhere in the environment in plants, animals, rocks and air. Incidental emissions occur when natural mercury is released to the environment through human activity. In Canada, coal burning and metal processing are the two largest point sources of atmospheric mercury emissions. Energy facilities have the option to invest in expensive control technologies for coal plants, or they can generate electricity from alternative energy sources. Energy conservation, however, offers the greatest overall benefits for the environment and the public. Mercury can also be released when products containing mercury (such as electrical switches, thermostats, dental amalgam, and thermometers) are broken while in use, or when they are crushed in garbage trucks and dumped in landfills. Source separation is the best way to reduce waste-related emissions. Once mercury is released to the natural environment, it can be transported long distances through air or watercourses. It is volatile, therefore evaporates readily to the atmosphere where it may do one of three things: it may fall out near the point where it was emitted; it may be transported long distances to some point downwind; or, it may enter the global atmospheric mercury pool where it will circle the globe for a year or more within the Earth's major weather systems before being deposited. Data from Canada's National Pollutant Release Inventory indicates that mercury releases and transfers total 28,674 kg per year. The most critical component of the mercury cycle is the conversion of inorganic forms of mercury to the organic compound methylmercury which is more toxic to humans. Most concern about mercury focuses on lakes and other aquatic ecosystems. Fish in hydroelectric reservoirs have been found to contain elevated methylmercury levels because natural

  11. 40 CFR Appendix Xiii to Part 266 - Mercury Bearing Wastes That May Be Processed in Exempt Mercury Recovery Units

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Mercury Bearing Wastes That May Be Processed in Exempt Mercury Recovery Units XIII Appendix XIII to Part 266 Protection of Environment... XIII to Part 266—Mercury Bearing Wastes That May Be Processed in Exempt Mercury Recovery Units These...

  12. Groundwater Modeling of Mercury Pollution at a Former Mercury Cell Chlor Alkali Facility in Pavlodar City, Kazakhstan

    Science.gov (United States)

    In northern Kazakhstan, there is a serious case of mercury pollution near the city of Pavlodar from an old mercury cell chlor-alkali plant. The soil, sediment, and water is severely contaminated with mercury and mercury compounds as a result of the industrial activity of this ch...

  13. The adaptive response of lichens to mercury exposure involves changes in the photosynthetic machinery

    International Nuclear Information System (INIS)

    Nicolardi, Valentina; Cai, Giampiero; Parrotta, Luigi; Puglia, Michele; Bianchi, Laura; Bini, Luca; Gaggi, Carlo

    2012-01-01

    Lichens are an excellent model to study the bioaccumulation of heavy metals but limited information is available on the molecular mechanisms occurring during bioaccumulation. We investigated the changes of the lichen proteome during exposure to constant concentrations of mercury. We found that most of changes involves proteins of the photosynthetic pathway, such as the chloroplastic photosystem I reaction center subunit II, the oxygen-evolving protein and the chloroplastic ATP synthase β-subunit. This suggests that photosynthesis is a target of the toxic effects of mercury. These findings are also supported by changes in the content of photosynthetic pigments (chlorophyll a and b, and β-carotene). Alterations to the photosynthetic machinery also reflect on the structure of thylakoid membranes of algal cells. Response of lichens to mercury also involves stress-related proteins (such as Hsp70) but not cytoskeletal proteins. Results suggest that lichens adapt to mercury exposure by changing the metabolic production of energy. - Highlights: ► Lichens exposed to Hg° vapors accumulate this metal irreversibly. ► Hg° interferes with physiological processes of the epiphytic lichen Evernia prunastri. ► Hg° promotes changes in the concentration of photosynthetic pigments. ► Hg° treatment causes changes in the ultrastructure of the photobiont plastids. ► Hg° induces changes in the protein machinery involved in the photosynthesis pathway. - Mercury affects the photosynthetic protein machinery of lichens.

  14. Dental amalgam and urinary mercury concentrations: a descriptive study

    OpenAIRE

    Nicolae, Alexandra; Ames, Harry; Qui?onez, Carlos

    2013-01-01

    Background Dental amalgam is a source of elemental and inorganic mercury. The safety of dental amalgam in individuals remains a controversial issue. Urinary mercury concentrations are used to assess chronic exposure to elemental mercury. At present, there are no indications of mercury-associated adverse effects at levels below 5??g Hg/g creatinine (Cr) or 7??g Hg/L (urine). The purpose of the present study is to determine the overall urinary mercury level in the Canadian general population in...

  15. Mercury's magnetosphere and magnetotial revisited

    International Nuclear Information System (INIS)

    Bergan, S.; Engle, I.M.

    1981-01-01

    Magnetic observations which are not complicated by currents of trapped plasma are a good test of geomagnetopause and geomagnetotail predictions. Recent attempts to model the Hermean magnetospheric field based on a planet-centered magnetic multipole field with a quadrupole moment in addition to the planetary dipole field or a dipole field linearly displaced from planet center and no quadrupole moment have produced reasonably good fits to the Mercury magnetic field measurements. In this work we find a better fit for a dipole displacement from the planet center by making use of an improved representation of the magnetic field in the magnetotail, where many of the Mercury measurements were made. The rms deviation of the data was reduced from 10. or 11. γ to 9.3 γ by employing this new tail field representation. Also, by making use of this new tail field representation, we find a best fit for a dipole displacement of -0.0285 R/sub M/ (earlier, 0.026 R/sub M/) toward the dawn in the magnetic equatorial plane and 0.17 R/sub M/ (earlier, 0.189 R/sub M/ (earlier 0.189 R/sub M/) northward along the magnetic dipole axis, where R/sub M/ is the planet radius. Thus with only minor adjustments in the displacement vector of the dipole from the planet center we achieve a measurable improvement in the fit of the data by using the improved magnetotail field representation

  16. A thin, dense crust for Mercury

    Science.gov (United States)

    Sori, Michael M.

    2018-05-01

    Crustal thickness is a crucial geophysical parameter in understanding the geology and geochemistry of terrestrial planets. Recent development of mathematical techniques suggests that previous studies based on assumptions of isostasy overestimated crustal thickness on some of the solid bodies of the solar system, leading to a need to revisit those analyses. Here, I apply these techniques to Mercury. Using MESSENGER-derived elemental abundances, I calculate a map of grain density (average 2974 ± 89 kg/m3) which shows that Pratt isostasy is unlikely to be a major compensation mechanism of Mercury's topography. Assuming Airy isostasy, I find the best fit value for Mercury's mean crustal thickness is 26 ± 11 km, 25% lower than the most recently reported and previously thinnest number. Several geological implications follow from this relatively low value for crustal thickness, including showing that the largest impacts very likely excavated mantle material onto Mercury's surface. The new results also show that Mercury and the Moon have a similar proportion of their rocky silicates composing their crusts, and thus Mercury is not uniquely efficient at crustal production amongst terrestrial bodies. Higher resolution topography and gravity data, especially for the southern hemisphere, will be necessary to refine Mercury's crustal parameters further.

  17. Elimination of mercury from amalgam in rats

    Energy Technology Data Exchange (ETDEWEB)

    Galic, N. [Dept. of Dental Pathology, School of Dentistry, Zagreb (Croatia); Prpic-Mehicic, G.; Prester, Lj.; Blanusa, M. [Inst. for Medical Research and Occupational Health, Zagreb (Croatia); Krnic, Z.; Erceg, D. [Pliva Pharmaceutical Co., Biomedicine Research Inst. ' ' Pliva' ' , Zagreb (Croatia)

    2001-07-01

    The aim of this study was to measure the urinary mercury excretion in rats exposed to amalgam over a two months period. Animals were either exposed to mercury from 4 dental amalgams or fed the diet containing powdered amalgams. The results showed significantly higher mercury amount in urine of both exposed groups than in control. Even two months after the amalgam had been placed in rats teeth, the amount of mercury in the urine remained 4-5 times higher than in control, and 4 times higher than in rats exposed to diet containing powdered amalgam. The elevated urinary Hg amount was accompanied by an increased level of total protein in urine. In the same exposure period the excretion of total protein in urine of rats with amalgam fillings was 2 times higher than in control and 1.5 times higher than in rats exposed to amalgam through diet. Concentrations of mercury in the sera of all groups were below the detection limit of the method. The results show that amount of mercury and protein in the urine of rats were related to the mercury release from dental amalgam. (orig.)

  18. Influence of the Mercury gravity field on the orbit insertion strategy of BepiColombo

    Science.gov (United States)

    Schuster, Anja; Jehn, Rüdiger

    2013-04-01

    Ziel des Versuchs BepiColombo is Europe's first mission to Mercury expected to launch on an Ariane 5 rocket in 2015. The European Space Agency (ESA), in cooperation with the Japan Aerospace Exploration Agency (JAXA), is responsible for the mission design and navigation. The mission has a high scientific interest as there are still many unsolved questions about Mercury, such as origin and evolution of the planet, its physical form, as well as its interior structure. Also instruments to measure the chemical composition, the exosphere and magnetosphere of Mercury will be on board of BepiColombo. The interplanetary journey based on ion propulsion and 7 gravity assists is followed by the challenging gravitational capture at Mercury. This paper describes the manoeuvre sequences of the Mercury Orbit Insertion (MOI). The manoeuvres were optimized such that the two scientific elements - the Mercury Magnetospheric Orbiter (MMO) and the Mercury Planetary Orbiter (MPO) - can be released to their target orbits with minimum fuel consumption. The MOI consists of fifteen burns: After five burns the MMO will be released to its operational orbit of 600 km x 11624 km; after the fifteenth burn MPO shall arrive at its target orbit of 560 km x 1530 km. The optimum burn sequence was obtained by implementing the optimization package SNOPT into an orbit propagation software that considers orbital perturbations due to the non-sphericity of Mercury and the gravitational pull of the Sun. Since the gravity field of Mercury is still not very well known - even after Messenger being in orbit around Mercury for almost two years - the final MPO orbit is still under discussion. Depending on the final choice of the MPO orbit, different orbit insertion sequences have to be optimised and the most probable ones are presented here. This also includes different argument of periherm values for MPO and MMO. Furthermore, the effect of the solar aspect angle constraints ("no direct Sun on MMO and on the

  19. Concentration of mercury in wheat samples stored with mercury tablets as preservative

    International Nuclear Information System (INIS)

    Lalit, B.Y.; Ramachandran, T.V.

    1977-01-01

    Tablets consisting of mercury in the form of a dull grey powder made by triturating mercury with chalk and sugar are used in Indian household for storing food-grains. The contamination of wheat samples by mercury, when stored with mercury tablets for period of upto four years has been assessed by using non-destructive neutron activation analysis. The details of the analytical procedure used have also been briefly described. The concentration of mercury in wheat increases with storage period. Loss of weight of mercury tablet is proportional to the storage period to a first approximation. In the present experiment, the average weight loss at the and end of first year was 0.009716 g corresponding to 6 ppm in wheat. (T.G.)

  20. Simultaneous spectrophotometric determination of mercury and palladium with Thio-Michler's Ketone using partial least squares regression and orthogonal signal correction

    Science.gov (United States)

    Niazi, Ali; Azizi, Amir; Ramezani, Majid

    2008-12-01

    A simple, novel and sensitive spectrophotometric method was described for simultaneous determination of mercury and palladium. The method is based on the complex formation of mercury and palladium with Thio-Michler's Ketone (TMK) at pH 3.5. All factors affecting on the sensitivity were optimized and the linear dynamic range for determination of mercury and palladium found. The simultaneous determination of mercury and palladium mixtures by using spectrophotometric method is a difficult problem, due to spectral interferences. By multivariate calibration methods such as partial least squares (PLS), it is possible to obtain a model adjusted to the concentration values of the mixtures used in the calibration range. Orthogonal signal correction (OSC) is a preprocessing technique used for removing the information unrelated to the target variables based on constrained principal component analysis. OSC is a suitable preprocessing method for PLS calibration of mixtures without loss of prediction capacity using spectrophotometric method. In this study, the calibration model is based on absorption spectra in the 360-660 nm range for 25 different mixtures of mercury and palladium. Calibration matrices were containing 0.025-1.60 and 0.05-0.50 μg mL -1 of mercury and palladium, respectively. The RMSEP for mercury and palladium with OSC and without OSC were 0.013, 0.006 and 0.048, 0.030, respectively. This procedure allows the simultaneous determination of mercury and palladium in synthetic and real matrix samples good reliability of the determination.

  1. Highly Reducing Partitioning Experiments Relevant to the Planet Mercury

    Science.gov (United States)

    Rowland, Rick, II; Vander Kaaden, Kathleen E.; McCubbin, Francis M.; Danielson, Lisa R.

    2017-01-01

    With the data returned from the MErcury Surface Space ENvironment GEochemistry and Ranging (MESSENGER) mission, there are now numerous constraints on the physical and chemical properties of Mercury, including its surface composition. The high S and low FeO contents observed from MESSENGER on the planet's surface suggests a low oxygen fugacity of the present planetary materials. Estimates of the oxygen fugacity for Mercurian magmas are approximately 3-7 log units below the Iron-Wüstite (Fe-FeO) oxygen buffer, several orders of magnitude more reducing than other terrestrial bodies we have data from such as the Earth, Moon, or Mars. Most of our understanding of elemental partitioning behavior comes from observations made on terrestrial rocks, but Mercury's oxygen fugacity is far outside the conditions of those samples. With limited oxygen available, lithophile elements may instead exhibit chalcophile, halophile, or siderophile behaviors. Furthermore, very few natural samples of rocks that formed under reducing conditions are available in our collections (e.g., enstatite chondrites, achondrites, aubrites). With this limited amount of material, we must perform experiments to determine the elemental partitioning behavior of typically lithophile elements as a function of decreasing oxygen fugacity. Experiments are being conducted at 4 GPa in an 880-ton multi-anvil press, at temperatures up to 1850degC. The composition of starting materials for the experiments were selected for the final run products to contain metal, silicate melt, and sulfide melt phases. Oxygen fugacity is controlled in the experiments by adding silicon metal to the samples, using the Si-SiO2 oxygen buffer, which is approximately 5 log units more reducing than the Fe-FeO oxygen buffer at our temperatures of interest. The target silicate melt compositional is diopside (CaMgSi2O6) because measured surface compositions indicate partial melting of a pyroxene-rich mantle. Elements detected on Mercury

  2. Hidden sources of mercury in clinical laboratories.

    Science.gov (United States)

    Alvarez-Chavez, C R; Federico-Perez, R A; Gomez-Alvarez, A; Velazquez-Contreras, L E; Perez-Rios, R

    2014-09-01

    The healthcare sector is an important contributor to mercury (Hg) pollution because of the potential presence of mercury in thermometers, blood pressure cuffs, amalgams, etc. There are also other potential sources of mercury in this sector which are used frequently and in high volumes where the presence of the metal is not obvious and which might be collectively contributing to pollution. For instance, some chemicals used for the clinical diagnosis of illness may contain mercury. The goal of this study was to investigate potential sources of mercury pollution, which originate from clinical laboratory discharges, using an exploratory approach. The focus was on the residue generated during automatic analysis of patients' bodily fluids at a medical center in Hermosillo, Sonora, Mexico. This study shows an overview of what might be happening in the region or the country related to non-obvious sources of mercury in the healthcare sector. The results showed measurable levels of mercury in the residues coming from urine sediment analysis. These amounts do not exceed the maximum allowed by Mexican environmental regulations; nevertheless, the frequency and cumulative volume of residues generated, combined with the potential for persistence and the bioaccumulation of mercury in the environment, warrant attention. The work carried out in this study is being taken as a model for future studies for pollution prevention in the healthcare sector with the goal of measuring mercury emissions to the environment from clinical laboratory wastewater, including identifying sources which--while not obvious--could be important given the frequency and volume of their use in the clinical diagnosis.

  3. New triiodomercurate-modified carbon paste electrode for the potentiometric determination of mercury

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, M.N.; Mostafa, G.A.E

    2003-02-22

    A new tetrazolium-triiodomercurate-modified carbon paste electrode has been described for the sensitive and selective determination of mercury. The electrode shows a stable, near-Nernstian response for 1x10{sup -3} to 6x10{sup -6} M [HgI{sub 3}]{sup -} at 25 deg. C over the pH range of 4.0-9.0, with an anionic slope of 55.5{+-}0.4 mV. The lower detection limit is 4x10{sup -6} M with a fast response time of 30-50 s. Selectivity coefficients of a number of interfering anions and iodo complexes of some metal ions have been estimated. The interference from many of the investigated ions is negligible. The determination of 1-200 {mu}g/ml of mercury in aqueous solutions shows an average recovery of 98.5% and a mean relative standard deviation of 1.6% at 50.0 {mu}g/ml. The direct determination of mercury in spiked wastewater, metal amalgams and dental alloy gave results that compare favorably with those obtained by the cold vapor atomic absorption spectrometric method. Potentiometric titration of mercury and phenylmercury acetate with standard potassium iodide has been monitored using the developed triiodomercurate-carbon paste electrode (CPE) as an end point indicator electrode.

  4. An Assessment of the Potential Effects of Aquifer Storage and Recovery on Mercury Cycling in South Florida

    Science.gov (United States)

    Krabbenhoft, David P.; Aiken, George R.; Anderson, Mary P.

    2007-01-01

    not represent a significant additional direct load of mercury and methyl-mercury to ASR 'receiving waters'. Net production of methylmercury, however, can result from additions of sulfate or natural organic carbon. Thus, because the Upper Floridan aquifer generally has elevated concentrations of sulfate (relative to ambient Everglades conditions) and surface waters near Lake Okeechobee (the assumed target for ASR receiving waters) are elevated in organic carbon and sulfate, at least some potential for increased methylmercury production might arise from the release of recovered ASR water to locations in or near the Everglades.

  5. The tropical African mercury anomaly: lower than expected mercury concentrations in fish and human hair.

    Science.gov (United States)

    Black, Frank J; Bokhutlo, Thethela; Somoxa, Aaron; Maethamako, Mothusi; Modisaemang, Ontlogetse; Kemosedile, Thebe; Cobb-Adams, Cristina; Mosepele, Ketlhatlogile; Chimbari, Moses

    2011-04-15

    Mercury is a neurotoxin and global pollutant, and wetlands and newly flooded areas are known to be sites of enhanced production of monomethylmercury, the form of mercury that is readily biomagnified in aquatic food chains to potentially toxic levels. The Okavango Delta in Botswana, Southern Africa, is the largest inland delta in the world and a wetland ecosystem that experiences dramatic annual flooding of large tracts of seasonal floodplains. The Delta was, therefore, expected to be home to high mercury levels in fish and to be an area where local subsistence fishing communities would be at substantial risk of mercury toxicity from fish consumption. Total mercury concentrations measured in 27 species of fish from the Okavango Delta averaged (mean±s.d., wet weight) 19±19ng g(-1) in non-piscivorous fish, and 59±53ng g(-1) in piscivorous fish. These mercury concentrations are similar to those reported for fish from lakes in other areas of tropical Africa, demonstrating that not all wetlands are sites of elevated mercury concentrations in biota. Even more intriguing is that concentrations of mercury in fish from across tropical Africa are systematically and substantially lower than those typically reported for fish from freshwater ecosystems elsewhere globally. The reasons for this apparent "African mercury anomaly" are unclear, but this finding poses a unique opportunity to improve our understanding of mercury's biogeochemical cycling in the environment. Mercury concentrations measured in human hair collected in subsistence fishing communities in the Okavango Delta were similarly low (0.21±0.22μg g(-1) dry weight) despite high levels of fish consumption, and reflect the low mercury concentrations in the fish here. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. Methyl mercury, but not inorganic mercury, associated with higher blood pressure during pregnancy.

    Science.gov (United States)

    Wells, Ellen M; Herbstman, Julie B; Lin, Yu Hong; Hibbeln, Joseph R; Halden, Rolf U; Witter, Frank R; Goldman, Lynn R

    2017-04-01

    Prior studies addressing associations between mercury and blood pressure have produced inconsistent findings; some of this may result from measuring total instead of speciated mercury. This cross-sectional study of 263 pregnant women assessed total mercury, speciated mercury, selenium, and n-3 polyunsaturated fatty acids in umbilical cord blood and blood pressure during labor and delivery. Models with a) total mercury or b) methyl and inorganic mercury were evaluated. Regression models adjusted for maternal age, race/ethnicity, prepregnancy body mass index, neighborhood income, parity, smoking, n-3 fatty acids and selenium. Geometric mean total, methyl, and inorganic mercury concentrations were 1.40µg/L (95% confidence interval: 1.29, 1.52); 0.95µg/L (0.84, 1.07); and 0.13µg/L (0.10, 0.17), respectively. Elevated systolic BP, diastolic BP, and pulse pressure were found, respectively, in 11.4%, 6.8%, and 19.8% of mothers. In adjusted multivariable models, a one-tertile increase of methyl mercury was associated with 2.83mmHg (0.17, 5.50) higher systolic blood pressure and 2.99mmHg (0.91, 5.08) higher pulse pressure. In the same models, an increase of one tertile of inorganic mercury was associated with -1.18mmHg (-3.72, 1.35) lower systolic blood pressure and -2.51mmHg (-4.49, -0.53) lower pulse pressure. No associations were observed with diastolic pressure. There was a non-significant trend of higher total mercury with higher systolic blood pressure. We observed a significant association of higher methyl mercury with higher systolic and pulse pressure, yet higher inorganic mercury was significantly associated with lower pulse pressure. These results should be confirmed with larger, longitudinal studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Isolation, screening and identification of mercury resistant bacteria from mercury contaminated soil

    OpenAIRE

    Kowalczyk Anna; Wilińska Magdalena; Chyc Marek; Bojko Monika; Latowski Dariusz

    2016-01-01

    New bacterial strains resistant to high concentration of mercury were obtained and character iz ed focusing on their potential application in bioremediation. The biological material was isolated from soil contaminated with mercury. The ability to removal of Hg from the liquid medium and the effect of the various pH and mercury concentrations in the environment on bacterial strains growth kinetics were tested. The selected strains were identified by analysis of the 16S ribosome subunit coding ...

  8. Mercury fluxes through the sediment water interface and bioavailability of mercury in southern Baltic Sea sediments

    Directory of Open Access Journals (Sweden)

    Jacek Bełdowski

    2009-06-01

    Full Text Available Sediment cores collected in several areas of the southern Baltic were analysed for total mercury (HgTOT and five operationally defined mercury fractions: HgA - contained in pore waters, HgF - bound to fulvic acids, HgH - bound to humic acids, HgS - bound to sulphide, and HgR - residual. An effort was made to quantify mercury fluxes at the sediment/water interface in the study area. Net mercury input, calculated on the basis of sedimentation rate and concentration in the uppermost sediments, ranged from 1 to 5.5 ng cm-2 year-1. Mercury remobilisation from sediments due to diffusion and resuspension was calculated from the proportion of labile mercury and the velocity of near-bottom currents. The results showed that the return soluble and particulate fluxes of mercury from the sediments to the water column constitute a substantial proportion of the input (20-50%, and are slightly higher than those found in pristine areas, although they are less than the values recorded in areas with a history of mercury contamination. In addition, an index was developed to assess the methylation potential of mercury in sediments. Mercury contained in pore waters, and mercury bound to fulvic and humic acids together with Loss on Ignition were used to calculate the semi-quantitative methylation potential (Pm. Despite the simplicity of this approach, Pm correlates well with methyl mercury in fish from the study area.full, complete article (PDF - compatibile with Acrobat 4.0, 291.3 kB

  9. determination of mercury content in milk powder

    International Nuclear Information System (INIS)

    Jovchev, M.; Grigorov, T.; Apostolov, D.

    1985-01-01

    Four samples of humanized full cream cow milk powder of Bulgarian origin for new-born, sucklings, small children and soured milk powder were activated for 18-24 h in a neutron flux of 5.10 12 , resp. 2.10 13 n/cm 2 .sec in quartz ampules. The samples were activated without preliminary lyophilization, thus avoiding possible mistakes from mercury losses. Ag-110m, being eliminated in the amalgam, was not an obstacle to the mercury determination. The results obtained for the mercury content are in the same order as in other investigations and many times lower than the admissible norm for foodstuffs - 50 ppb

  10. Effect of mercury on algal growth rates

    Energy Technology Data Exchange (ETDEWEB)

    Hannan, P.J.; Patouillet, C.

    1972-01-01

    In experiments with one freshwater (Chlorella pyrenoidosa) and three marine organisms (Phaeodactylum tricornutum, Cyclotella nana, and Chaetoceras gavestonensis), mercury was more toxic than the other metals tested (silver, cadmium, lead, and copper); and its toxicity is comparatively irreversible. Growth was monitored by changes in fluorescence of the cultures over a 3-day test period. The toxicity of the mercury varied inversely with the concentrations of nutrients present. Preliminary experiments indicate that mercury in the form of mercuric chloride is more toxic than as dimethylmercury. 12 references, 3 figures, 1 table.

  11. Conditioning of spent mercury by amalgamation

    International Nuclear Information System (INIS)

    Yim, S. P.; Shon, J. S.; An, B. G.; Lee, H. J.; Lee, J. W.; Ji, C. G.; Kim, S. H.; Yoon, J. H.; Yang, M. S.

    2002-01-01

    Solidification by amalgamation was performed to immobilize and stabilize the liquid spent mercury. First, the appropriate metal and alloy which can convert liquid mercury into a solid form of amalgam were selected through initial tests. The amalgam form, formulated in optimum composition, was characterized and subjected to performance tests including compressive strength, water immersion, leachability and initial vaporization rate to evaluate mechanical integrity, durability and leaching properties. Finally, bench scale amalgamation trial was conducted with about 1 kg of spent mercury to verify the feasibility of amalgamation method

  12. Physical properties of the planet Mercury

    Science.gov (United States)

    Clark, Pamela E.

    1988-01-01

    The global physical properties of Mercury are summarized with attention given to its figure and orbital parameters. The combination of properties suggests that Mercury has an extensive iron-rich core, possibly with a still-functioning dynamo, which is 42 percent of the interior by volume. Mercury's three major axes are comparable in size, indicating that the planet is a triaxial ellipsoid rather than an oblate spheroid. In terms of the domination of its surface by an intermediate plains terrane, it is more Venus- or Mars-like; however, due to the presence of a large metallic magnetic core, its interior may be more earth-like.

  13. MESSENGER'S First and Second Flybys of Mercury

    Science.gov (United States)

    Slavin, James A.

    2009-01-01

    The MESSENGER mission to Mercury offers our first opportunity to explore this planet's miniature magnetosphere since Mariner 10's brief fly-bys in 1974-5. The magnetosphere of Mercury is the smallest in the solar system with its magnetic field typically standing off the solar wind only approximately 1000 km above the surface. An overview of the MESSENGER mission and its January 14th and October 6th, 2008 close flybys of Mercury will be provided. Primary science objectives and the science instrumentation will be described. Initial results from MESSENGER will be discussed with an emphasis on the magnetic field and charged particle measurements.

  14. Method development for the control determination of mercury in seafood by solid-sampling thermal decomposition amalgamation atomic absorption spectrometry (TDA AAS).

    Science.gov (United States)

    Torres, D P; Martins-Teixeira, M B; Silva, E F; Queiroz, H M

    2012-01-01

    A very simple and rapid method for the determination of total mercury in fish samples using the Direct Mercury Analyser DMA-80 was developed. In this system, a previously weighted portion of fresh fish is combusted and the released mercury is selectively trapped in a gold amalgamator. Upon heating, mercury is desorbed from the amalgamator, an atomic absorption measurement is performed and the mercury concentration is calculated. Some experimental parameters have been studied and optimised. In this study the sample mass was about 100.0 mg. The relative standard deviation was lower than 8.0% for all measurements of solid samples. Two calibration curves against aqueous standard solutions were prepared through the low linear range from 2.5 to 20.0 ng of Hg, and the high linear range from 25.0 to 200.0 ng of Hg, for which a correlation coefficient better than 0.997 was achieved, as well as a normal distribution of the residuals. Mercury reference solutions were prepared in 5.0% v/v nitric acid medium. Lyophilised fish tissues were also analysed; however, the additional procedure had no advantage over the direct analysis of the fresh fish, and additionally increased the total analytical process time. A fish tissue reference material, IAEA-407, was analysed and the mercury concentration was in agreement with the certified value, according to the t-test at a 95% confidence level. The limit of quantification (LOQ), based on a mercury-free sample, was 3.0 µg kg(-1). This LOQ is in accordance with performance criteria required by the Commission Regulation No. 333/2007. Simplicity and high efficiency, without the need for any sample preparation procedure, are some of the qualities of the proposed method.

  15. 17 CFR 200.71 - Fiduciary relationships.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Fiduciary relationships. 200...; CONDUCT AND ETHICS; AND INFORMATION AND REQUESTS Canons of Ethics § 200.71 Fiduciary relationships. A... are involved in questions to be determined by him. Such relationships would include trustees...

  16. 34 CFR 200.30 - Local review.

    Science.gov (United States)

    2010-07-01

    ..., DEPARTMENT OF EDUCATION TITLE I-IMPROVING THE ACADEMIC ACHIEVEMENT OF THE DISADVANTAGED Improving Basic... the greatest need for special assistance, consistent with the requirements of section 1115 of the ESEA... 34 Education 1 2010-07-01 2010-07-01 false Local review. 200.30 Section 200.30 Education...

  17. 15 CFR 200.101 - Measurement research.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Measurement research. 200.101 Section..., PROCEDURES, AND FEES § 200.101 Measurement research. (a) The NIST staff continually reviews the advances in... research and development activities of NIST are primarily funded by direct appropriations, and are aimed at...

  18. 17 CFR 200.10 - The Commission.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false The Commission. 200.10 Section 200.10 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION ORGANIZATION; CONDUCT AND... The Commission. The Commission is composed of five members, not more than three of whom may be members...

  19. 13 CFR 106.200 - Cosponsored Activity.

    Science.gov (United States)

    2010-01-01

    ...(h) of the Small Business Act. ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Cosponsored Activity. 106.200 Section 106.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION COSPONSORSHIPS, FEE AND NON...

  20. 17 CFR 200.70 - Business promotions.

    Science.gov (United States)

    2010-04-01

    ... AND ETHICS; AND INFORMATION AND REQUESTS Canons of Ethics § 200.70 Business promotions. A member must not engage in any other business, employment or vocation while in office, nor may he ever use the... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Business promotions. 200.70...

  1. 24 CFR 200.78 - Energy conservation.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Energy conservation. 200.78 Section... Eligibility Requirements for Existing Projects Property Requirements § 200.78 Energy conservation... conservation in accordance with standards established by the Commissioner. Mortgage Provisions ...

  2. 34 CFR 200.81 - Program definitions.

    Science.gov (United States)

    2010-07-01

    ... year-round only if, within 18 months after the effective date of this regulation and at least once... 34 Education 1 2010-07-01 2010-07-01 false Program definitions. 200.81 Section 200.81 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION...

  3. 14 CFR 1251.200 - Discrimination prohibited.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Discrimination prohibited. 1251.200 Section... OF HANDICAP Employment Practices § 1251.200 Discrimination prohibited. (a) General. (1) No qualified handicapped person shall, on the basis of handicap, be subjected to discrimination in employment under any...

  4. 17 CFR 200.505 - Original classification.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Original classification. 200...; CONDUCT AND ETHICS; AND INFORMATION AND REQUESTS Classification and Declassification of National Security Information and Material § 200.505 Original classification. (a) No Commission Member or employee has the...

  5. 17 CFR 200.506 - Derivative classification.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Derivative classification. 200...; CONDUCT AND ETHICS; AND INFORMATION AND REQUESTS Classification and Declassification of National Security Information and Material § 200.506 Derivative classification. Any document that includes paraphrases...

  6. 24 CFR 200.73 - Property development.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Property development. 200.73 Section 200.73 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT GENERAL INTRODUCTION TO FHA PROGRAMS Requirements for Application, Commitment, and...

  7. 42 CFR 495.200 - Definitions.

    Science.gov (United States)

    2010-10-01

    ... AND CERTIFICATION STANDARDS FOR THE ELECTRONIC HEALTH RECORD TECHNOLOGY INCENTIVE PROGRAM Requirements... certified EHR technology in accordance with § 495.4 of this part. (5) Is not a “hospital-based EP” as that... 42 Public Health 5 2010-10-01 2010-10-01 false Definitions. 495.200 Section 495.200 Public Health...

  8. 30 CFR 250.200 - Definitions.

    Science.gov (United States)

    2010-07-01

    ... part. Non-conventional production or completion technology includes, but is not limited to, floating... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Definitions. 250.200 Section 250.200 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR...

  9. 34 CFR 200.71 - LEA eligibility.

    Science.gov (United States)

    2010-07-01

    ... least five percent of the LEA's total population ages 5 to 17 years, inclusive. (d) Education finance... 34 Education 1 2010-07-01 2010-07-01 false LEA eligibility. 200.71 Section 200.71 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION...

  10. 34 CFR 200.63 - Consultation.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Consultation. 200.63 Section 200.63 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING THE ACADEMIC ACHIEVEMENT OF THE DISADVANTAGED Improving Basic...

  11. 31 CFR 28.200 - Application.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Application. 28.200 Section 28.200 Money and Finance: Treasury Office of the Secretary of the Treasury NONDISCRIMINATION ON THE BASIS OF... Application. Except as provided in §§ 28.205 through 28.235(a), these Title IX regulations apply to every...

  12. 17 CFR 200.110 - Purpose.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Purpose. 200.110 Section 200.110 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION ORGANIZATION; CONDUCT AND ETHICS; AND INFORMATION AND REQUESTS Code of Behavior Governing Ex Parte Communications Between Persons...

  13. 17 CFR 200.114 - Sanctions.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Sanctions. 200.114 Section 200.114 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION ORGANIZATION; CONDUCT AND ETHICS; AND INFORMATION AND REQUESTS Code of Behavior Governing Ex Parte Communications Between Persons...

  14. Injurious effect of mercury vapor from bichloride of mercury in soil of rose houses

    Energy Technology Data Exchange (ETDEWEB)

    Zimmerman, P.W.; Crocker, W.

    1933-01-01

    Addition of mercuric chloride, or corrosive sublimate, to Rose soil for killing earthworms may injure the Roses. The organic matter of the soil reduces the bichloride to metallic mercury and the vapors of the mercury rise into the air and kill the buds and peduncles. When the soil is rich in tankage or other organic matter, the rate of reduction of the bichloride is increased and thereby the severity of the injury intensified. If a container of metallic mercury is set in an enclosed chamber with Rose plants, severe injuries of the type mentioned below soon appear. The Briarcliff Rose is especially susceptible to mercury injury. 1 figure.

  15. Mercury Information Clearinghouse. Quarterly 3: advanced and developmental mercury control technologies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    Advanced mercury control technologies for coal-fired electric utilities are reviewed. The technologies evaluated are at various stages of development and most have been tested under limited operational conditions. The following technologies are described: K-Fuel and K-Fuel Plus pre-combustion technology, combustion modification and in situ generation of sorbents, new sorbent developments, direct bromine injection, MerCAP{sup {trademark}} (Mercury Control via Adsorption Process, Gore felt filter bag inserts, EnviroScrub Pahlman{sup {trademark}} process, combined oxidation of NO{sub x} and mercury, and mercury control with the Advanced Hybrid{trademark} filter. 36 refs., 1 fig.

  16. Inorganic mercury exposure, mercury-copper interaction, and DMPS treatment in rats.

    OpenAIRE

    Blanusa, M; Prester, L; Radić, S; Kargacin, B

    1994-01-01

    The aim of this study was to evaluate the efficiency of oral treatment with sodium 2,3-dimercaptopropane-1-sulfonate (DMPS) on reducing mercury deposits in rat kidney after chronic exposure to inorganic mercury. The effect on kidney copper levels was also evaluated. The results showed that after two months of exposure to 50 ppm of mercury (as mercuric chloride) the concentration of mercury in the kidney was 124 micrograms/g wet tissue. At the same time copper concentration rose from 11 to 77 ...

  17. Mercury nano-trap for effective and efficient removal of mercury(II) from aqueous solution

    Science.gov (United States)

    Li, Baiyan; Zhang, Yiming; Ma, Dingxuan; Shi, Zhan; Ma, Shengqian

    2014-11-01

    Highly effective and highly efficient decontamination of mercury from aqueous media remains a serious task for public health and ecosystem protection. Here we report that this task can be addressed by creating a mercury ‘nano-trap’ as illustrated by functionalizing a high surface area and robust porous organic polymer with a high density of strong mercury chelating groups. The resultant porous organic polymer-based mercury ‘nano-trap’ exhibits a record-high saturation mercury uptake capacity of over 1,000 mg g-1, and can effectively reduce the mercury(II) concentration from 10 p.p.m. to the extremely low level of smaller than 0.4 p.p.b. well below the acceptable limits in drinking water standards (2 p.p.b.), and can also efficiently remove >99.9% mercury(II) within a few minutes. Our work therefore presents a new benchmark for mercury adsorbent materials and provides a new perspective for removing mercury(II) and also other heavy metal ions from contaminated water for environmental remediation.

  18. Spall and damage behavior of S200F beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Chris D [Los Alamos National Laboratory; Anderson, William W [Los Alamos National Laboratory; Gray, George T [Los Alamos National Laboratory; Blumenthal, William R [Los Alamos National Laboratory; Owens, Chuck T [Los Alamos National Laboratory; Freibert, Franz J [Los Alamos National Laboratory; Montoya, Johnny M [Los Alamos National Laboratory; Contreras, Paul J [Los Alamos National Laboratory

    2009-01-01

    We have performed a series of plate impact experiments to study the strength and spall damage behavior of S200F Be. Peak stresses achieved were in the range from 5.6-19.2 GPa. VISAR data show long rise times in the approach to the shocked state believed to be the result of twinning occurring alongside, or in defference to slip, in this hcp material, with its free surface never achieving a steady velocity. This data indicate brittle spall behavior with spall strengths in the range of 0.8-0.9 GPa. In experiments where target thickness is varied, we see evidence of precursor decay and present calculations of the Hugoniot Elastic Limit (HEL). Beryllium is a strategically important material to the aerospace and defense industries worldwide. In spite of this, there is surprisingly little recent literature on the dynamic behavior of this material, particularly the S200F grade. Much of the earlier work was performed on either S200D or S200E grades of Be [1,2] from Brush Wellman, Inc., or on material of unstated pedigree [3]. A discussion of the evolution in material processing, resulting chemical composition, grain size, and crystallographic texture in these as-processed grades of Be can be found in [4]. In general, progressing from S200D, to E, to F entails reduced BeO and other impurity contents, reduced grain size, and a reduction in crystallographic texture of the starting material [4]. The primary goal of this investigation was to study the strength and damage behavior of S200F under dynamic loading conditions. A secondary goal was to obtain equation-of-state (EOS) data to supplement and compare with those already reported in the literature.

  19. Tundra uptake of atmospheric elemental mercury drives Arctic mercury pollution

    Science.gov (United States)

    Obrist, Daniel; Agnan, Yannick; Jiskra, Martin; Olson, Christine L.; Colegrove, Dominique P.; Hueber, Jacques; Moore, Christopher W.; Sonke, Jeroen E.; Helmig, Detlev

    2017-07-01

    Anthropogenic activities have led to large-scale mercury (Hg) pollution in the Arctic. It has been suggested that sea-salt-induced chemical cycling of Hg (through ‘atmospheric mercury depletion events’, or AMDEs) and wet deposition via precipitation are sources of Hg to the Arctic in its oxidized form (Hg(II)). However, there is little evidence for the occurrence of AMDEs outside of coastal regions, and their importance to net Hg deposition has been questioned. Furthermore, wet-deposition measurements in the Arctic showed some of the lowest levels of Hg deposition via precipitation worldwide, raising questions as to the sources of high Arctic Hg loading. Here we present a comprehensive Hg-deposition mass-balance study, and show that most of the Hg (about 70%) in the interior Arctic tundra is derived from gaseous elemental Hg (Hg(0)) deposition, with only minor contributions from the deposition of Hg(II) via precipitation or AMDEs. We find that deposition of Hg(0)—the form ubiquitously present in the global atmosphere—occurs throughout the year, and that it is enhanced in summer through the uptake of Hg(0) by vegetation. Tundra uptake of gaseous Hg(0) leads to high soil Hg concentrations, with Hg masses greatly exceeding the levels found in temperate soils. Our concurrent Hg stable isotope measurements in the atmosphere, snowpack, vegetation and soils support our finding that Hg(0) dominates as a source to the tundra. Hg concentration and stable isotope data from an inland-to-coastal transect show high soil Hg concentrations consistently derived from Hg(0), suggesting that the Arctic tundra might be a globally important Hg sink. We suggest that the high tundra soil Hg concentrations might also explain why Arctic rivers annually transport large amounts of Hg to the Arctic Ocean.

  20. Tundra uptake of atmospheric elemental mercury drives Arctic mercury pollution.

    Science.gov (United States)

    Obrist, Daniel; Agnan, Yannick; Jiskra, Martin; Olson, Christine L; Colegrove, Dominique P; Hueber, Jacques; Moore, Christopher W; Sonke, Jeroen E; Helmig, Detlev

    2017-07-12

    Anthropogenic activities have led to large-scale mercury (Hg) pollution in the Arctic. It has been suggested that sea-salt-induced chemical cycling of Hg (through 'atmospheric mercury depletion events', or AMDEs) and wet deposition via precipitation are sources of Hg to the Arctic in its oxidized form (Hg(ii)). However, there is little evidence for the occurrence of AMDEs outside of coastal regions, and their importance to net Hg deposition has been questioned. Furthermore, wet-deposition measurements in the Arctic showed some of the lowest levels of Hg deposition via precipitation worldwide, raising questions as to the sources of high Arctic Hg loading. Here we present a comprehensive Hg-deposition mass-balance study, and show that most of the Hg (about 70%) in the interior Arctic tundra is derived from gaseous elemental Hg (Hg(0)) deposition, with only minor contributions from the deposition of Hg(ii) via precipitation or AMDEs. We find that deposition of Hg(0)-the form ubiquitously present in the global atmosphere-occurs throughout the year, and that it is enhanced in summer through the uptake of Hg(0) by vegetation. Tundra uptake of gaseous Hg(0) leads to high soil Hg concentrations, with Hg masses greatly exceeding the levels found in temperate soils. Our concurrent Hg stable isotope measurements in the atmosphere, snowpack, vegetation and soils support our finding that Hg(0) dominates as a source to the tundra. Hg concentration and stable isotope data from an inland-to-coastal transect show high soil Hg concentrations consistently derived from Hg(0), suggesting that the Arctic tundra might be a globally important Hg sink. We suggest that the high tundra soil Hg concentrations might also explain why Arctic rivers annually transport large amounts of Hg to the Arctic Ocean.

  1. A high-power target experiment

    CERN Document Server

    Kirk, H G; Ludewig, H; Palmer, Robert; Samulyak, V; Simos, N; Tsang, Thomas; Bradshaw, T W; Drumm, Paul V; Edgecock, T R; Ivanyushenkov, Yury; Bennett, Roger; Efthymiopoulos, Ilias; Fabich, Adrian; Haseroth, H; Haug, F; Lettry, Jacques; Hayato, Y; Yoshimura, Koji; Gabriel, Tony A; Graves, Van; Spampinato, P; Haines, John; McDonald, Kirk T

    2005-01-01

    We describe an experiment designed as a proof-of-principle test for a target system capable of converting a 4 MW proton beam into a high-intensity muon beam suitable for incorporation into either a neutrino factory complex or a muon collider. The target system is based on exposing a free mercury jet to an intense proton beam in the presence of a high strength solenoidal field.

  2. Full-Scale Testing of a Mercury Oxidation Catalyst Upstream of a Wet FGD System

    Energy Technology Data Exchange (ETDEWEB)

    Gary Blythe; Jennifer Paradis

    2010-06-30

    This document presents and discusses results from Cooperative Agreement DE-FC26-06NT42778, 'Full-scale Testing of a Mercury Oxidation Catalyst Upstream of a Wet FGD System,' which was conducted over the time-period July 24, 2006 through June 30, 2010. The objective of the project was to demonstrate at full scale the use of solid honeycomb catalysts to promote the oxidation of elemental mercury in pulverized-coal-fired flue gas. Oxidized mercury is removed downstream in wet flue gas desulfurization (FGD) absorbers and collected with the byproducts from the FGD system. The project was co-funded by EPRI, the Lower Colorado River Authority (LCRA), who also provided the host site, Great River Energy, Johnson Matthey, Southern Company, Salt River Project (SRP), the Tennessee Valley Authority (TVA), NRG Energy, Ontario Power and Westar. URS Group was the prime contractor and also provided cofunding. The scope of this project included installing and testing a gold-based catalyst upstream of one full-scale wet FGD absorber module (about 200-MW scale) at LCRA's Fayette Power Project (FPP) Unit 3, which fires Powder River Basin coal. Installation of the catalyst involved modifying the ductwork upstream of one of three wet FGD absorbers on Unit 3, Absorber C. The FGD system uses limestone reagent, operates with forced sulfite oxidation, and normally runs with two FGD modules in service and one spare. The full-scale catalyst test was planned for 24 months to provide catalyst life data. Over the test period, data were collected on catalyst pressure drop, elemental mercury oxidation across the catalyst module, and mercury capture by the downstream wet FGD absorber. The demonstration period began on May 6, 2008 with plans for the catalyst to remain in service until May 5, 2010. However, because of continual increases in pressure drop across the catalyst and concerns that further increases would adversely affect Unit 3 operations, LCRA decided to end the

  3. Regulation of alternative splicing of Bcl-x by BC200 contributes to breast cancer pathogenesis

    Science.gov (United States)

    Singh, R; Gupta, S C; Peng, W-X; Zhou, N; Pochampally, R; Atfi, A; Watabe, K; Lu, Z; Mo, Y-Y

    2016-01-01

    BC200 is a long non-coding RNA (lncRNA) that has been implicated in the regulation of protein synthesis, yet whether dysregulation of BC200 contributes to the pathogenesis of human diseases remains elusive. In this study, we show that BC200 is upregulated in breast cancer; among breast tumor specimens there is a higher level of BC200 in estrogen receptor (ER) positive than in ER-negative tumors. Further experiments show that activation of estrogen signaling induces expression of BC200. To determine the significance of ER-regulated BC200 expression, we knockout (KO) BC200 by CRISPR/Cas9. BC200 KO suppresses tumor cell growth in vitro and in vivo by expression of the pro-apoptotic Bcl-xS isoform. Mechanistically, BC200 contains a 17-nucleotide sequence complementary to Bcl-x pre-mRNA, which may facilitate its binding to Bcl-x pre-mRNA and recruitment of heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1, a known splicing factor. Consequently, hnRNP A2/B1 interferes with association of Bcl-x pre-mRNA with the Bcl-xS-promoting factor Sam68, leading to a blockade of Bcl-xS expression. Together, these results suggest that BC200 plays an oncogenic role in breast cancer. Thus, BC200 may serve as a prognostic marker and possible target for attenuating deregulated cell proliferation in estrogen-dependent breast cancer. PMID:27277684

  4. Mercury pollution in Wuchuan mercury mining area, Guizhou, Southwestern China: the impacts from large scale and artisanal mercury mining.

    Science.gov (United States)

    Li, Ping; Feng, Xinbin; Qiu, Guangle; Shang, Lihai; Wang, Shaofeng

    2012-07-01

    To evaluate the environmental impacts from large scale mercury mining (LSMM) and artisanal mercury mining (AMM), total mercury (THg) and methyl mercury (MeHg) were determined in mine waste, ambient air, stream water and soil samples collected from Wuchuan mercury (Hg) mining area, Guizhou, Southwestern China. Mine wastes from both LSMM and AMM contained high THg concentrations, which are important Hg contamination sources to the local environment. Total gaseous mercury (TGM) concentrations in the ambient air near AMM furnaces were highly elevated, which indicated that AMM retorting is a major source of Hg emission. THg concentrations in the stream water varied from 43 to 2100 ng/L, where the elevated values were mainly found in the vicinity of AMM and mine waste heaps of LSMM. Surface soils were seriously contaminated with Hg, and land using types and organic matter played an important role in accumulation and transportation of Hg in soil. The results indicated heavy Hg contaminations in the study area, which were resulted from both LSMM and AMM. The areas impacted by LSMM were concentrated in the historical mining and smelting facilities, while Hg pollution resulted from AMM can be distributed anywhere in the Hg mining area. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Mercury content in electrum from artisanal mining site of Mongolia

    Energy Technology Data Exchange (ETDEWEB)

    Murao, Satoshi [Geological Survey of Japan, AIST, Higashi 1-1-1, No. 7, Tsukuba 305-8567 (Japan)]. E-mail: s.murao@aist.go.jp; Naito, Kazuki [Geological Survey of Japan, AIST, Higashi 1-1-1, No. 7, Tsukuba 305-8567 (Japan); Dejidmaa, Gunchin [Geological Information Center, Mineral and Petroleum Resources Authority of Mongolia, State Building No. 5, Ulaanbaatar (Mongolia); Sie, Soey H. [CSIRO, P.O. Box 136, North Ryde, NSW 1670 (Australia)

    2006-08-15

    In Mongolia, artisanal gold mining, modern gold rush, in which people use mercury to extract gold, is being proliferated rapidly and the mercury contamination of mining site is becoming a serious social issue. For the risk assessment of mercury, it is necessary to understand how much mercury is introduced to the environment from what kind of materials during mining activity. It is already known that major contribution of the contamination comes from mercury that was bought at shops and brought to mining sites by miners. However, no information is available on how much mercury is removed from electrum (natural gold grain) to the environment. Since gold deposit is always accompanied by mercury anomaly, it is anticipated that electrum grains contain some amount of mercury of natural origin, and this mercury (primary mercury) contributes to some extent to the contamination. In order to clarify how much mercury is incorporated in electrum grains, micro-PIXE at CSIRO was used for grain-by-grain analysis. The result showed that electrum from study area contains mercury up to 8260 ppm. It is concluded that for the risk management of mercury contamination, release of natural mercury from electrum grains during smelting must not be ignored.

  6. Mercury content in electrum from artisanal mining site of Mongolia

    Science.gov (United States)

    Murao, Satoshi; Naito, Kazuki; Dejidmaa, Gunchin; Sie, Soey H.

    2006-08-01

    In Mongolia, artisanal gold mining, modern gold rush, in which people use mercury to extract gold, is being proliferated rapidly and the mercury contamination of mining site is becoming a serious social issue. For the risk assessment of mercury, it is necessary to understand how much mercury is introduced to the environment from what kind of materials during mining activity. It is already known that major contribution of the contamination comes from mercury that was bought at shops and brought to mining sites by miners. However, no information is available on how much mercury is removed from electrum (natural gold grain) to the environment. Since gold deposit is always accompanied by mercury anomaly, it is anticipated that electrum grains contain some amount of mercury of natural origin, and this mercury (primary mercury) contributes to some extent to the contamination. In order to clarify how much mercury is incorporated in electrum grains, micro-PIXE at CSIRO was used for grain-by-grain analysis. The result showed that electrum from study area contains mercury up to 8260 ppm. It is concluded that for the risk management of mercury contamination, release of natural mercury from electrum grains during smelting must not be ignored.

  7. Bioavailability and stability of mercury sulfide in Armuchee (USA) soil

    International Nuclear Information System (INIS)

    Han, Fengxiang; Shiyab, Safwan; Su, Yi; Monts, David L.; Waggoner, Charles A.; Matta, Frank B.

    2007-01-01

    Because of the adverse effects of elemental mercury and mercury compounds upon human health, the U.S. Department of Energy (DOE) is engaged in an on-going effort to monitor and remediate mercury-contaminated DOE sites. In order to more cost effectively implement those extensive remediation efforts, it is necessary to obtain an improved understanding of the role that mercury and mercury compounds play in the ecosystem. We have conducted pilot scale experiments to study the bioavailability of mercury sulfide in an Armuchee (eastern US ) soil. The effects of plants and incubation time on chemical stability and bioavailability of HgS under simulated conditions of the ecosystem have been examined, as has the dynamics of the dissolution of mercury sulfide by various extractants. The results show that mercury sulfide in contaminated Armuchee soil was still to some extent bioavailable to plants. After planting, soil mercury sulfide is more easily dissolved by both 4 M and 12 M nitric acid than pure mercury sulfide reagent. Dissolution kinetics of soil mercury sulfide and pure chemical reagent by nitric acid are different. Mercury release by EDTA from HgS-contaminated soil increased with time of reaction and soil mercury level. Chelating chemicals increase the solubility and bioavailability of mercury in HgS-contaminated soil. (authors)

  8. Mercury content in electrum from artisanal mining site of Mongolia

    International Nuclear Information System (INIS)

    Murao, Satoshi; Naito, Kazuki; Dejidmaa, Gunchin; Sie, Soey H.

    2006-01-01

    In Mongolia, artisanal gold mining, modern gold rush, in which people use mercury to extract gold, is being proliferated rapidly and the mercury contamination of mining site is becoming a serious social issue. For the risk assessment of mercury, it is necessary to understand how much mercury is introduced to the environment from what kind of materials during mining activity. It is already known that major contribution of the contamination comes from mercury that was bought at shops and brought to mining sites by miners. However, no information is available on how much mercury is removed from electrum (natural gold grain) to the environment. Since gold deposit is always accompanied by mercury anomaly, it is anticipated that electrum grains contain some amount of mercury of natural origin, and this mercury (primary mercury) contributes to some extent to the contamination. In order to clarify how much mercury is incorporated in electrum grains, micro-PIXE at CSIRO was used for grain-by-grain analysis. The result showed that electrum from study area contains mercury up to 8260 ppm. It is concluded that for the risk management of mercury contamination, release of natural mercury from electrum grains during smelting must not be ignored

  9. Environmental chemistry and toxicology of mercury

    National Research Council Canada - National Science Library

    Liu, Guangliang; Cai, Yong; O'Driscoll, Nelson J

    2012-01-01

    ... employed in recent studies. The coverage discusses the environmental behavior and toxicological effects of mercury on organisms, including humans, and provides case studies at the end of each chapter...

  10. Filter for isotopic alteration of mercury vapor

    Science.gov (United States)

    Grossman, Mark W.; George, William A.

    1989-01-01

    A filter for enriching the .sup.196 Hg content of mercury, including a reactor, a low pressure electric discharge lamp containing a fill of mercury and an inert gas. A filter is arranged concentrically around the lamp. The reactor is arranged around said filter, whereby radiation from said lamp passes through the filter and into said reactor. The lamp, the filter and the reactor are formed of quartz, and are transparent to ultraviolet light. The .sup.196 Hg concentration in the mercury fill is less than that which is present in naturally occurring mercury, that is less than about 0.146 atomic weight percent. Hydrogen is also included in the fill and serves as a quenching gas in the filter, the hydrogen also serving to prevent disposition of a dark coating on the interior of the filter.

  11. Chemistry of impact events on Mercury

    Science.gov (United States)

    Berezhnoy, Alexey A.

    2018-01-01

    Based on the equilibrium thermochemical approach and quenching theory, formation of molecules and dust grains in impact-produced clouds formed after collisions between meteoroids and Mercury is considered. Based on observations of Al, Fe, and Mn atoms in the exosphere of Mercury and new results of studies of the elemental composition of the surface of Mercury, quenching temperatures and pressures of main chemical reactions and condensation of dust particles were estimated. The behavior of the main Na-, K-, Ca-, Fe-, Al-, Mn-, Mg-, Si-, Ti, Ni-, Cr-, Co, Zn-, O-, H-, S-, C-, Cl-, N-, and P-containing species delivered to the Hermean exosphere during meteoroid impacts was studied. The importance of meteoroid bombardment as a source of Na, K, Ca, Fe, Al, Mn, Mg, and O atoms in the exosphere of Mercury is discussed.

  12. Mercury in the South African environment

    CSIR Research Space (South Africa)

    Matooane, M

    2009-11-01

    Full Text Available ? Mercury, also known as quick silver, is ubiquitous in the environment ? Uses - Medical: medicines, thermometers, dental amalgam, etc. - Manufacturing industry: batteries, gold mining, chlorine production, cement production, etc. - Personal care...

  13. Mercury sorbent delivery system for flue gas

    Science.gov (United States)

    Klunder,; Edgar, B [Bethel Park, PA

    2009-02-24

    The invention presents a device for the removal of elemental mercury from flue gas streams utilizing a layer of activated carbon particles contained within the filter fabric of a filter bag for use in a flue gas scrubbing system.

  14. Environmental chemistry and toxicology of mercury

    National Research Council Canada - National Science Library

    Liu, Guangliang; Cai, Yong; O'Driscoll, Nelson J

    2012-01-01

    .... Bringing together information normally spread across several books, this text is unique in covering the entire mercury cycle and providing a baseline for what is known and what uncertainties remain...

  15. Natural stable isotopic compositions of mercury in aerosols and wet precipitations around a coal-fired power plant in Xiamen, southeast China

    Science.gov (United States)

    Huang, Shuyuan; Sun, Lumin; Zhou, Tingjin; Yuan, Dongxing; Du, Bing; Sun, Xiuwu

    2018-01-01

    In this study, samples of 18 wet precipitations (WPs) and 38 aerosols were collected around a coal-fired power plant (CFPP) located in Xiamen, southeast China, which was equipped with a seawater flue gas desulfurization system. Total particulate mercury (TPM) in aerosol samples, and total mercury (WP-TM), dissolved mercury (WP-DM) and particulate mercury (WP-PM) in WP samples were analyzed for the natural isotopic compositions of mercury. For the first time, both mass dependent fractionation (MDF) and mass independent fractionation of odd (odd-MIF) and even (even-MIF) isotopes of WP-DM and WP-PM were reported and discussed. Both WP-TM and TPM displayed negative MDF and slightly positive even-MIF. Negative odd-MIF was observed in TPM and WP-PM, whereas positive odd-MIF was observed in WP-TM and WP-DM. It was found that the mercury budget in WP-PM samples was mainly controlled by atmospheric particles. Potential sources of mercury in samples were identified via analysis of mercury isotopic signatures and meteorological data with the NOAA HYSPLIT model. The results showed that TPM and WP-PM in solid samples were homologous and the isotopic compositions of WP-TM depended on those of WP-DM. The ratios of Δ199Hg/Δ201Hg resulting from photochemical reactions and positive Δ200Hg values (from -0.06‰ to 0.27‰) in all samples indicated that the mercury coming from local emission of the CFPP together with long-distance transportation were the two main contributing sources.

  16. Mercury and halogens in coal--Their role in determining mercury emissions from coal combustion

    Science.gov (United States)

    Kolker, Allan; Quick, Jeffrey C.; Senior, Connie L.; Belkin, Harvey E.

    2012-01-01

    Mercury is a toxic pollutant. In its elemental form, gaseous mercury has a long residence time in the atmosphere, up to a year, allowing it to be transported long distances from emission sources. Mercury can be emitted from natural sources such as volcanoes, or from anthropogenic sources, such as coal-fired powerplants. In addition, all sources of mercury on the Earth's surface can re-emit it from land and sea back to the atmosphere, from which it is then redeposited. Mercury in the atmosphere is present in such low concentrations that it is not considered harmful. Once mercury enters the aquatic environment, however, it can undergo a series of biochemical transformations that convert a portion of the mercury originally present to methylmercury, a highly toxic organic form of mercury that accumulates in fish and birds. Many factors contribute to creation of methylmercury in aquatic ecosystems, including mercury availability, sediment and nutrient load, bacterial influence, and chemical conditions. In the United States, consumption of fish with high levels of methylmercury is the most common pathway for human exposure to mercury, leading the U.S. Environmental Protection Agency (EPA) to issue fish consumption advisories in every State. The EPA estimates that 50 percent of the mercury entering the atmosphere in the United States is emitted from coal-burning utility powerplants. An EPA rule, known as MATS (for Mercury and Air Toxics Standards), to reduce emissions of mercury and other toxic pollutants from powerplants, was signed in December 2011. The rule, which is currently under review, specifies limits for mercury and other toxic elements, such as arsenic, chromium, and nickel. MATS also places limits on emission of harmful acid gases, such as hydrochloric acid and hydrofluoric acid. These standards are the result of a 2010 detailed nationwide program by the EPA to sample stack emissions and thousands of shipments of coal to coal-burning powerplants. The United

  17. Gamma radiation stability studies of mercury fulminate

    International Nuclear Information System (INIS)

    Fondeur, F.F.

    2000-01-01

    Mercury fulminate completely decomposed in a gamma source (0.86 Mrad/h) after a dose of 208 Mrad. This exposure equates to approximately 2.4 years in Tank 15H and 4 years in Tank 12H, one of the vessels of concern. Since the tanks lost the supernatant cover layer more than a decade ago, this study suggests that any mercury fulminate or closely related energetic species decomposed long ago if ever formed

  18. Gamma radiation stability studies of mercury fulminate

    Energy Technology Data Exchange (ETDEWEB)

    Fondeur, F.F.

    2000-02-17

    Mercury fulminate completely decomposed in a gamma source (0.86 Mrad/h) after a dose of 208 Mrad. This exposure equates to approximately 2.4 years in Tank 15H and 4 years in Tank 12H, one of the vessels of concern. Since the tanks lost the supernatant cover layer more than a decade ago, this study suggests that any mercury fulminate or closely related energetic species decomposed long ago if ever formed.

  19. Stratigraphy and geologic history of Mercury

    International Nuclear Information System (INIS)

    Spudis, P.D.; Guest, J.E.

    1988-01-01

    The geologic evolution of Mercury based on the Mariner-10 mission data is discussed. As reconstructed through photogeological analysis of global geologic relations of rock-stratigraphic units, Mercury's geologic history is shown to involve intensive early impact bombardment and widespread resurfacing by volcanic lavas. Evidence is presented to indicate that this volcanic activity essentially ended as much as 3 Gyr ago, with most of the major geologic events being completed within the first 1 to 1.5 Gyr of Mercurian history

  20. Mercury's global evolution: New views from MESSENGER

    Science.gov (United States)

    Hauck, S. A., II; Byrne, P. K.; Denevi, B. W.; Grott, M.; McCoy, T.; Stanley, S.

    2015-12-01

    MESSENGER's exploration of Mercury has revealed the planet's rich and dynamic history and provided new constraints on the processes that control its internal evolution. Mercury's surface records evidence of an extensive geological history. This evidence includes resurfacing by impacts and volcanism prior to the end of the late heavy bombardment (LHB) and a subsequent rapid waning of effusive volcanism. Volcanism is an important indicator of the history of melt production. Thousands of globally distributed, contractional tectonic landforms collectively have accommodated a decrease in Mercury's radius of 5-7 km since the end of the LHB. Such contraction results from planetary cooling and crystallization within Mercury's metallic core. Measurements of surface chemistry have provided constraints on internal radiogenic heat production necessary to understand more fully Mercury's thermal evolution. Elemental abundances also reveal that Mercury is strongly chemically reduced, suggesting that the core's iron is alloyed with silicon as well as sulfur, which constrains the dynamics and crystallization of the metallic core. Magnetometer observations show that Mercury's dynamo-generated, dominantly dipolar field is displaced ~500 km northward along the rotation axis. Low-altitude magnetic field observations late in the mission led to the discovery of crustal magnetization in Mercury's ancient crust, dating to at least 3.7 Ga, which places a new constraint on the timing of the dynamo. Monte Carlo parameterized mantle convection models, constrained by these observations, indicate that for global contraction of 7 km or less, mantle convection persists to the present ~40% of the time, with the likelihood of modern convection decreasing with less global contraction. Slow present cooling in these models indicates that dynamo generation is strongly influenced by both a static layer at the top of the core and convective motions within the core driven by compositional buoyancy.