Sample records for zinc lead mercury

  1. Mercury removal from aqueous solutions by zinc cementation.

    PubMed

    Ku, Young; Wu, Ming-Huan; Shen, Yung-Shen

    2002-01-01

    The main purpose of this research is to study the addition effect of the surfactant and other operating factors on the treatment of wastewater containing mercury ions in aqueous solution by cementation with sacrificing metal, zinc. The removal of mercury ions from aqueous solutions by cementation of zinc powder was found to be a function of solution pH and temperature, amount of zinc, concentration of mercury ion, contact time and the addition of several organic surfactants. Cementation of mercury was shown to be a feasible process to achieve a very high degree of mercury removal over a broad operational range within a fairly reasonable contact time. The reaction rate is approximately first order with respect to the concentration of mercury ion in aqueous solution. Among the surfactants used in this study, only the presence of SDS, an anionic surfactant, slightly enhanced the cementation rate of mercury. The presence of CTAB and Triton-X100 retarded the cementation of mercury by zinc.

  2. Survey of mercury, cadmium and lead content of household batteries.

    PubMed

    Recknagel, Sebastian; Radant, Hendrik; Kohlmeyer, Regina

    2014-01-01

    The objective of this work was to provide updated information on the development of the potential impact of heavy metal containing batteries on municipal waste and battery recycling processes following transposition of the new EU Batteries Directive 2006/66/EC. A representative sample of 146 different types of commercially available dry and button cells as well as lithium-ion accumulators for mobile phones were analysed for their mercury (Hg)-, cadmium (Cd)- and lead (Pb)-contents. The methods used for preparing the cells and analysing the heavy metals Hg, Cd, and Pb were either developed during a former study or newly developed. Several batteries contained higher mass fractions of mercury or cadmium than the EU limits. Only half of the batteries with mercury and/or lead fractions above the marking thresholds were labelled. Alkaline-manganese mono-cells and Li-ion accumulators, on average, contained the lowest heavy metal concentrations, while zinc-carbon batteries, on average, contained the highest levels. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Recent trends and current practices for secondary processing of zinc and lead. Part II: zinc recovery from secondary sources.

    PubMed

    Sahu, Kamala Kanta; Agrawal, Archana; Pandey, Banshi Dhar

    2004-08-01

    Almost all metallurgical processes are associated with the generation of wastes and residues that may be hazardous or non-hazardous in nature depending upon the criteria specified by institutions such as the US Environment Protection Agency, etc. Wastes containing heavy and toxic metals such as arsenic, cadmium, chromium, nickel, lead, copper, mercury, zinc, etc., that are present beyond permissible limits deemed to be treated or disposed of, and non-hazardous wastes can be utilized for metal recovery or safe disposal. Zinc is in growing demand all over the world. In India, a major amount of zinc is imported and therefore processing of zinc secondaries will assist in satisfying the gap between demand and supply to some extent. This report mainly focuses on the current practices and recent trends on the secondary processing of zinc. Attempts made by various laboratories to develop ecofriendly processes for the recovery of zinc from secondary raw materials are also described and discussed.

  4. Electronic characterization of defects in narrow gap semiconductors: Comparison of electronic energy levels and formation energies in mercury cadmium telluride, mercury zinc telluride, and mercury zinc selenide

    NASA Technical Reports Server (NTRS)

    Patterson, James D.; Li, Wei-Gang

    1995-01-01

    The project has evolved to that of using Green's functions to predict properties of deep defects in narrow gap materials. Deep defects are now defined as originating from short range potentials and are often located near the middle of the energy gap. They are important because they affect the lifetime of charge carriers and hence the switching time of transistors. We are now moving into the arena of predicting formation energies of deep defects. This will also allow us to make predictions about the relative concentrations of the defects that could be expected at a given temperature. The narrow gap materials mercury cadmium telluride (MCT), mercury zinc telluride (MZT), and mercury zinc selenide (MZS) are of interest to NASA because they have commercial value for infrared detecting materials, and because there is a good possibility that they can be grown better in a microgravity environment. The uniform growth of these crystals on earth is difficult because of convection (caused by solute depletion just ahead of the growing interface, and also due to thermal gradients). In general it is very difficult to grow crystals with both radial and axial homogeneity.

  5. Immobilization of mercury and zinc in an alkali-activated slag matrix.

    PubMed

    Qian, Guangren; Sun, Darren Delai; Tay, Joo Hwa

    2003-07-04

    The behavior of heavy metals mercury and zinc immobilized in an alkali-activated slag (AAS) matrix has been evaluated using physical property tests, pore structure analysis and XRD, TG-DTG, FTIR and TCLP analysis. Low concentrations (0.5%) of mercury and zinc ions had only a slight affect on compressive strength, pore structure and hydration of AAS matrixes. The addition of 2% Hg ions to the AAS matrix resulted in a reduction in early compressive strength but no negative effects were noticed after 28 days of hydration. Meanwhile, 2% Hg ions can be effectively immobilized in the AAS matrix with the leachate meeting the USEPA TCLP mercury limit. For a 2% Zn-doped AAS matrix, the hydration of the AAS paste was greatly retarded and the zinc concentration in the leachate from this matrix was higher than 5mg/l even at 28 days. Based on these results, we conclude that the physical encapsulation and chemical fixation mechanisms were likely to be responsible for the immobilization of Hg ions in the AAS matrix while only chemical fixation mechanisms were responsible for the immobilization of Zn ions in the AAS matrix.

  6. [Evaluation and source analysis of the mercury pollution in soils and vegetables around a large-scale zinc smelting plant].

    PubMed

    Liu, Fang; Wang, Shu-Xiao; Wu, Qing-Ru; Lin, Hai

    2013-02-01

    The farming soil and vegetable samples around a large-scale zinc smelter were collected for mercury content analyses, and the single pollution index method with relevant regulations was used to evaluate the pollution status of sampled soils and vegetables. The results indicated that the surface soil and vegetables were polluted with mercury to different extent. Of the soil samples, 78% exceeded the national standard. The mercury concentration in the most severely contaminated area was 29 times higher than the background concentration, reaching the severe pollution degree. The mercury concentration in all vegetable samples exceeded the standard of non-pollution vegetables. Mercury concentration, in the most severely polluted vegetables were 64.5 times of the standard, and averagely the mercury concentration in the vegetable samples was 25.4 times of the standard. For 85% of the vegetable samples, the mercury concentration, of leaves were significantly higher than that of roots, which implies that the mercury in leaves mainly came from the atmosphere. The mercury concentrations in vegetable roots were significantly correlated with that in soils, indicating the mercury in roots was mainly from soil. The mercury emissions from the zinc smelter have obvious impacts on the surrounding soils and vegetables. Key words:zinc smelting; mercury pollution; soil; vegetable; mercury content

  7. [Mercury pollution in cricket in different biotopes suffering from pollution by zinc smelting].

    PubMed

    Zheng, Dong-Mei; Li, Xin-Xin; Luo, Qing

    2012-10-01

    Total mercury contents in cricket bodies were studied in different biotopes in the surrounding of Huludao Zinc Plant to discuss the mercury distribution characteristics in cricket and to reveal the effects of environmental mercury accumulation in the short life-cycle insects through comparing cricket with other insect species. The average mercury content in cricket was 0.081 mg x kg(-1) and much higher than those in the control sites (0.012 mg x kg(-1) in average) in different biotopes. Mercury contents were found in the order of cricket head > wing > thorax approximately abdomen > leg. Mercury contents in cricket bodies varied greatly with sample sites. Significant correlation was found between the mercury contents in cricket and the distance from the pollution source as well as the mercury contents in plant stems. No significant correlation was found between the mercury contents in soil and in cricket bodies. Mercury contents in cricket were lower than those in cicadae, similar to those in other insects with shorter life-cycle periods.

  8. Electronic Characterization of Defects in Narrow Gap Semiconductors-Comparison of Electronic Energy Levels and Formation Energies in Mercury Cadmium Telluride, Mercury Zinc Telluride, and Mercury Zinc Selenide

    NASA Technical Reports Server (NTRS)

    Patterson, James D.

    1996-01-01

    We have used a Green's function technique to calculate the energy levels and formation energy of deep defects in the narrow gap semiconductors mercury cadmium telluride (MCT), mercury zinc telluride (MZT) and mercury zinc selenide (MZS). The formation energy is calculated from the difference between the total energy with an impurity cluster and the total energy for the perfect crystal. Substitutional (including antisite), interstitial (self and foreign), and vacancy deep defects are considered. Relaxation effects are calculated (with molecular dynamics). By use of a pseudopotential, we generalize the ideal vacancy model so as to be able to consider relaxation for vacancies. Different charge states are considered and the charged state energy shift (as computed by a modified Haldane-Anderson model) can be twice that due to relaxation. Different charged states for vacancies were not calculated to have much effect on the formation energy. For all cases we find deep defects in the energy gap only for cation site s-like orbitals or anion site p-like orbitals, and for the substitutional case only the latter are appreciably effected by relaxation. For most cases for MCT, MZT, MZS, we consider x (the concentration of Cd or Zn) in the range appropriate for a band gap of 0.1 eV. For defect energy levels, the absolute accuracy of our results is limited, but the precision is good, and hence chemical trends are accurately predicted. For the same reason, defect formation energies are more accurately predicted than energy level position. We attempt, in Appendix B, to calculate vacancy formation energies using relatively simple chemical bonding ideas due to Harrison. However, these results are only marginally accurate for estimating vacancy binding energies. Appendix C lists all written reports and publications produced for the grant. We include abstracts and a complete paper that summarizes our work which is not yet available.

  9. Zinc halogen battery electrolyte composition with lead additive

    DOEpatents

    Henriksen, Gary L.

    1981-01-01

    This disclosure relates to a zinc halogen battery electrolyte composition containing an additive providing improved zinc-on-zinc recyclability. The improved electrolyte composition involves the use of a lead additive to inhibit undesirable irregular plating and reduce nodular or dendritic growth on the electrode surface. The lead-containing electrolyte composition of the present invention appears to influence not only the morphology of the base plate zinc, but also the morphology of the zinc-on-zinc replate. In addition, such lead-containing electrolyte compositions appear to reduce hydrogen formation.

  10. Possible role of zinc in diminishing lead-related occupational stress-a zinc nutrition concern.

    PubMed

    Wani, Ab Latif; Ahmad, Ajaz; Shadab, G G H A; Usmani, Jawed Ahmad

    2017-03-01

    Lead and zinc are mostly present at the same occupational source and usually found as co-contaminants. Lead is known to associate with detrimental effects to humans. Zinc however is an essential nutrient and its deficiency causes debilitating effects on growth and development. Besides, it acts as core ion of important enzymes and proteins. The purpose of this study was to examine if zinc concentrations are associated with blood lead levels and if zinc may prevent lead-induced DNA damage. Blood samples were collected from 92 workers as participants occupationally exposed to lead or lead and zinc and 38 comparison participants having no history of such exposure. Lead and zinc levels were determined from blood by atomic absorption spectrophotometry and genetic damage was assessed by comet assay. Correlation was calculated by Spearman's rho. Lead concentrations were observed to increase among workers with increase in years of exposure. There was a significant difference (p < 0.001) in blood lead levels between workers and controls. In addition, significant difference (p < 0.001) in the genetic damage was observed among workers and controls. A clear effect of increased occupational exposure was visible among workers. Multiple regression analysis further reveals the positive effect of lead, while as the inverse effect of zinc on DNA damage. The results suggest that zinc may influence body lead absorption and may have a role in preventing the genetic damage caused by lead.

  11. Mineral resource of the month: mercury

    USGS Publications Warehouse

    Brooks, William E.

    2006-01-01

    The ore of mercury, cinnabar, is soft and dark red, and native mercury is one of a few metals that is liquid at room temperatures. Cinnabar from Almaden, Spain, the world’s oldest producing mercury mine, was used during Roman times, and the chemical symbol for mercury (Hg) is from "hydrargyrum," from the Greek word meaning liquid silver. Cinnabar and mercury are associated with some hydrothermal mineral deposits and occur in fine-grained or sedimentary and volcanic rocks near hot springs or volcanic centers. Mercury may be recovered as a byproduct of processing copper, gold, lead-zinc or silver.

  12. Pituitary gland levels of mercury, selenium, iron, and zinc in an Alzheimer`s disease study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cornett, C.R.; Markesbery, W.R.; Wekstein, D.R.

    1996-12-31

    Mercury, iron, selenium, and zinc imbalances have been observed in comparisons between Alzheimer`s disease (AD) and control subject brains. Analyses of the pituitary gland have demonstrated that this organ retains relatively high concentrations of trace elements, including mercury, iron, and zinc. Our previous work has shown that the pituitary glands of AD and control subjects are typically higher in these trace elements than brain samples from the same subject. Instrumental neutron activation analysis (INAA) was used to compare the pituitary trace element levels of AD and control subjects. This study also describes the intrasubject relationships of brain trace element levelsmore » to those in the pituitary gland of AD and control subjects.« less

  13. Reference Data for the Density and Viscosity of Liquid Cadmium, Cobalt, Gallium, Indium, Mercury, Silicon, Thallium, and Zinc

    NASA Astrophysics Data System (ADS)

    Assael, Marc J.; Armyra, Ivi J.; Brillo, Juergen; Stankus, Sergei V.; Wu, Jiangtao; Wakeham, William A.

    2012-09-01

    The available experimental data for the density and viscosity of liquid cadmium, cobalt, gallium, indium, mercury, silicon, thallium, and zinc have been critically examined with the intention of establishing both a density and a viscosity standard. All experimental data have been categorized into primary and secondary data according to the quality of measurement, the technique employed and the presentation of the data, as specified by a series of criteria. The proposed standard reference correlations for the density of liquid cadmium, cobalt, gallium, indium, silicon, thallium, and zinc are characterized by percent deviations at the 95% confidence level of 0.6, 2.1, 0.4, 0.5, 2.2, 0.9, and 0.7, respectively. In the case of mercury, since density reference values already exist, no further work was carried out. The standard reference correlations for the viscosity of liquid cadmium, cobalt, gallium, indium, mercury, silicon, thallium, and zinc are characterized by percent deviations at the 95% confidence level of 9.4, 14.0, 13.5, 2.1, 7.3, 15.7, 5.1, and 9.3, respectively.

  14. Mercury exposure, nutritional deficiencies and metabolic disruptions may affect learning in children

    PubMed Central

    Dufault, Renee; Schnoll, Roseanne; Lukiw, Walter J; LeBlanc, Blaise; Cornett, Charles; Patrick, Lyn; Wallinga, David; Gilbert, Steven G; Crider, Raquel

    2009-01-01

    Among dietary factors, learning and behavior are influenced not only by nutrients, but also by exposure to toxic food contaminants such as mercury that can disrupt metabolic processes and alter neuronal plasticity. Neurons lacking in plasticity are a factor in neurodevelopmental disorders such as autism and mental retardation. Essential nutrients help maintain normal neuronal plasticity. Nutritional deficiencies, including deficiencies in the long chain polyunsaturated fatty acids eicosapentaenoic acid and docosahexaenoic acid, the amino acid methionine, and the trace minerals zinc and selenium, have been shown to influence neuronal function and produce defects in neuronal plasticity, as well as impact behavior in children with attention deficit hyperactivity disorder. Nutritional deficiencies and mercury exposure have been shown to alter neuronal function and increase oxidative stress among children with autism. These dietary factors may be directly related to the development of behavior disorders and learning disabilities. Mercury, either individually or in concert with other factors, may be harmful if ingested in above average amounts or by sensitive individuals. High fructose corn syrup has been shown to contain trace amounts of mercury as a result of some manufacturing processes, and its consumption can also lead to zinc loss. Consumption of certain artificial food color additives has also been shown to lead to zinc deficiency. Dietary zinc is essential for maintaining the metabolic processes required for mercury elimination. Since high fructose corn syrup and artificial food color additives are common ingredients in many foodstuffs, their consumption should be considered in those individuals with nutritional deficits such as zinc deficiency or who are allergic or sensitive to the effects of mercury or unable to effectively metabolize and eliminate it from the body. PMID:19860886

  15. Mercury contribution to an Adirondack lake

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scrudato, R.J.; Long, D.; Weinbloom, R.

    1987-01-01

    Elevated copper, lead, and zinc concentrations in the upper 10 to 20 cm of sediment sampled from Cranberry Lake, a large Adirondack lake, are attributed to atmospheric contributions. Pb-210 and pollen core data, however, suggest Cranberry Lake also received mercury discharges during the turn of the century when the area was the center of extensive lumbering and related activities. Elevated mercury concentrations in Cranberry Lake smallmouth bass derived from remobilization from mercury-contaminated bottom sediments which increased the bioavailability to Cranberry Lake organisms. Mercury remobilization and accumulation by fish are promoted by fluctuating pH values resulting from acid precipitation.

  16. Mercury contribution to an adirondack lake

    NASA Astrophysics Data System (ADS)

    Scrudato, R. J.; Long, D.; Weinbloom, Robert

    1987-10-01

    Elevated copper, lead, and zinc concentrations in the upper 10 to 20 cm of sediment sampled from Cranberry Lake, a large Adirondack lake, are attributed to atmospheric contributions. Pb-210 and pollen core data, however, suggest Cranberry Lake also received mercury discharges during the turn of the century when the area was the center of extensive lumbering and related activities. Elevated mercury concentrations in Cranberry Lake smallmouth bass derived from remobilization from mercury-contaminated bottom sediments which increased the bioavailability to Cranberry Lake organisms. Mercury remobilization and accumulation by fish are promoted by fluctuating pH values resulting from acid precipilation.

  17. Lead and zinc dust depositions from ore trains characterised using lead isotopic compositions.

    PubMed

    Kristensen, L J; Taylor, M P; Morrison, A L

    2015-03-01

    This study investigates an unusual source of environmental lead contamination - the emission and deposition of lead and zinc concentrates along train lines into and out of Australia's oldest silver-lead-zinc mine at Broken Hill, Australia. Transport of lead and zinc ore concentrates from the Broken Hill mines has occurred for more than 125 years, during which time the majority was moved in uncovered rail wagons. A significant amount of ore was lost to the adjoining environments, resulting in soil immediately adjacent to train lines elevated with concentrations of lead (695 mg kg(-1)) and zinc (2230 mg kg(-1)). Concentrations of lead and zinc decreased away from the train line and also with depth shown in soil profiles. Lead isotopic compositions demonstrated the soil lead contained Broken Hill ore in increasing percentages closer to the train line, with up to 97% apportioned to the mined Broken Hill ore body. SEM examination showed ceiling dusts collected from houses along the train line were composed of unweathered galena particles, characteristic of the concentrate transported in the rail wagons. The loss of ore from the uncovered wagons has significantly extended the environmental footprint of contamination from local mining operations over an area extending hundreds of kilometres along each of the three train lines.

  18. LEAD AND MERCURY EACH AS PRIME MATTER IN ALCHEMY

    PubMed Central

    Mahdihassan, S.

    1988-01-01

    Prime Matter is matter-cum-energy. The first substance identified as such was lead. When gently heated it becomes red and redness means soul or energy so that lead was potentially red or soul-like and as such dual natured. Mercury also becomes red and can return to white metal. It was thus dual natured and was the second substance recognized as Prime Matter. First lead alone and then lead and mercury were considered as the source of all metals. PMID:22557603

  19. Neurotoxicity of dental amalgam is mediated by zinc.

    PubMed

    Lobner, D; Asrari, M

    2003-03-01

    The use of dental amalgam is controversial largely because it contains mercury. We tested whether amalgam caused toxicity in neuronal cultures and whether that toxicity was caused by mercury. In this study, we used cortical cell cultures to show for the first time that amalgam causes nerve cell toxicity in culture. However, the toxicity was not blocked by the mercury chelator, 2,3-dimercaptopropane-1-sulphonate (DMPS), but was blocked by the metal chelator, calcium disodium ethylenediaminetetraacetate (CaEDTA). DMPS was an effective mercury chelator in this system, since it blocked mercury toxicity. Of the components that comprise amalgam (mercury, zinc, tin, copper, and silver), only zinc neurotoxicity was blocked by CaEDTA. These results indicate that amalgam is toxic to nerve cells in culture by releasing zinc. While zinc is known to be neurotoxic, ingestion of zinc is not a major concern because zinc levels in the body are tightly regulated.

  20. Removal of lead and zinc ions from water by low cost adsorbents.

    PubMed

    Mishra, P C; Patel, R K

    2009-08-30

    In this study, activated carbon, kaolin, bentonite, blast furnace slag and fly ash were used as adsorbent with a particle size between 100 mesh and 200 mesh to remove the lead and zinc ions from water. The concentration of the solutions prepared was in the range of 50-100 mg/L for lead and zinc for single and binary systems which are diluted as required for batch experiments. The effect of contact time, pH and adsorbent dosage on removal of lead and zinc by adsorption was investigated. The equilibrium time was found to be 30 min for activated carbon and 3h for kaolin, bentonite, blast furnace slag and fly ash. The most effective pH value for lead and zinc removal was 6 for activated carbon. pH value did not effect lead and zinc removal significantly for other adsorbents. Adsorbent doses were varied from 5 g/L to 20 g/L for both lead and zinc solutions. An increase in adsorbent doses increases the percent removal of lead and zinc. A series of isotherm studies was undertaken and the data evaluated for compliance was found to match with the Langmuir and Freundlich isotherm models. To investigate the adsorption mechanism, the kinetic models were tested, and it follows second order kinetics. Kinetic studies reveals that blast furnace slag was not effective for lead and zinc removal. The bentonite and fly ash were effective for lead and zinc removal.

  1. Lead and zinc intoxication in companion birds.

    PubMed

    Puschner, Birgit; Poppenga, Robert H

    2009-01-01

    Although the toxicity of lead and zinc to birds is widely recognized by veterinarians and bird owners, these metals are frequently found in the environments of pet and aviary birds, and intoxications are common. Clinical signs exhibited by intoxicated birds are often nonspecific, which makes early diagnosis difficult. Fortunately, lead and zinc analyses of whole blood and serum or plasma, respectively, are readily available and inexpensive; elevated concentrations can confirm intoxication. Once diagnosed, intoxication can be effectively treated by (1) preventing further exposure, (2) administering chelating drugs, and (3) providing symptomatic and supportive care.

  2. Correlations between lead, cadmium, copper, zinc, and iron concentrations in frozen tuna fish

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Galindo, L.; Hardisson, A.; Montelongo, F.G.

    1986-04-01

    The presence of metallic pollutants in marine ecosystems has promoted wide research plans in order to evaluate pollution levels in marine organisms. However, little is known concerning environmental and physiological processes that regulate the concentration of trace metals in marine organisms. Even though the toxicity of lead and cadmium is well established, copper, zinc and iron are considered as essential elements for mammals. Little is known about heavy metals, other than mercury, concentrations in fresh and frozen tuna fish. Fifty samples obtained at the entrance of a canning factory in Santa Cruz de Tenerife (Canary Islands), were analyzed by atomicmore » absorption spectrophotometry. Results were treated by applying the Statistical Package for the Social Sciences compiled and linked in the software of a Digital VAX/VMS 11/780 computer.« less

  3. Mercury Poisoning from an Unsuspected Source

    PubMed Central

    Tamir, M.; Bornstein, B.; Behar, M.; Chwat, M.

    1964-01-01

    In the manufacture of zinc oxide the raw material normally used in zinc metal plates. In a factory in which old aeroplane batteries containing zinc mercury amalgam were substituted, it was not realized that mercury vapour was being produced. Of 25 workers exposed, seven developed serious chronic mercury poisoning and were admitted to hospital. The clinical findings in the affected workers are described. They were first treated with penicillamine D, but in all but one case this had to be stopped because of rashes. Little improvement followed a switch to B.A.L. It is suggested that if penicillamine D is used in the treatment of mercury poisoning, steroid cover should be given from the start. PMID:14249900

  4. From lead to manganese through mercury: mythology, science, and lessons for prevention.

    PubMed

    Alessio, Lorenzo; Campagna, Marcello; Lucchini, Roberto

    2007-11-01

    Lead (Pb), mercury (Hg), and manganese (Mn) are well-known neurotoxic metals. The knowledge of toxicity was developed through an extensive amount of research, starting with lead and mercury and proceeding today with manganese. Unfortunately, the consequent implementation of preventive measures was generally delayed, causing important negative effects to the exposed populations. A review and historical reconstruction of the research development that yielded modern understanding of lead and mercury neurotoxicity was conducted to derive useful lessons for the prevention of manganese neurotoxicity. Medieval alchemists named planets and metals from gods since they were already aware of the toxicity and the adverse effects caused by lead and mercury. Historical lessons learned from these two metals may help to avoid the repetition of further mistakes regarding other neurotoxic metals like manganese. The knowledge and experience on the toxicokinetics and toxicodynamics of lead and mercury is useful and valuable to identify a proper approach to "safe" exposure levels for manganese. Further information is still needed on the early neurotoxic and neurobehavioral effects after prolonged exposure to very low doses of lead, mercury, and manganese. Nevertheless, according to the precautionary principle, effective preventive measures should be already undertaken to prevent the onset of more severe health effects in the population. This is the most important lesson to be learned and applied from more than 30 years of occupational and environmental neurotoxicology of metals. (c) 2007 Wiley-Liss, Inc.

  5. Copper and zinc content in wild game shot with lead or non-lead ammunition - implications for consumer health protection.

    PubMed

    Schlichting, Daniela; Sommerfeld, Christine; Müller-Graf, Christine; Selhorst, Thomas; Greiner, Matthias; Gerofke, Antje; Ulbig, Ellen; Gremse, Carl; Spolders, Markus; Schafft, Helmut; Lahrssen-Wiederholt, Monika

    2017-01-01

    The aim of this study was to examine the contamination of game meat with copper and zinc and establish whether the use of alternative (non-lead) ammunition can lead to higher or unsafe levels of copper and zinc in the meat of roe deer, wild boar and red deer. The research project "Safety of game meat obtained through hunting" (LEMISI) was conducted in Germany with the purpose of examining the entry of lead as well as copper and zinc into the meat of hunted game when using either lead or non-lead ammunition. The outcome of this study shows that the usage of both lead-based ammunition and alternative non-lead ammunition results in the entry of copper and zinc into the edible parts of the game. Using non-lead ammunition does not entail dangerously elevated levels of copper and zinc, so replacing lead ammunition with alternative ammunition does not introduce a further health problem with regard to these metals. The levels of copper and zinc in game meat found in this study are in the range found in previous studies of game. The content of copper and zinc in game meat is also comparable to those regularly detected in meat and its products from livestock (pig, cattle, sheep) for which the mean human consumption rate is much higher. From the viewpoint of consumer health protection, the use of non-lead ammunition does not pose an additional hazard through copper and zinc contamination. A health risk due to the presence of copper and zinc in game meat at typical levels of consumer exposure is unlikely for both types of ammunition.

  6. Optimization of method for zinc analysis in several bee products on renewable mercury film silver based electrode.

    PubMed

    Opoka, Włodzimierz; Szlósarczyk, Marek; Maślanka, Anna; Piech, Robert; Baś, Bogusław; Włodarczyk, Edyta; Krzek, Jan

    2013-01-01

    Zinc is an interesting target for detection as it is one of the elements necessary for the proper functioning of the human body, its excess and deficiency can cause several symptoms. Several techniques including electrochemistry have been developed but require laboratory equipment, preparative steps and mercury or complex working electrodes. We here described the development of a robust, simple and commercially available electrochemical system. Differential pulse (DP) voltammetry was used for this purpose with the cyclic renewable mercury film silver based electrode (Hg(Ag)FE) and 0.05 M KNO3 solution as a supporting electrolyte. The effect of various factors such as: preconcentration potential and time, pulse amplitude and width, step potential and supporting electrolyte composition are optimized. The limits of detection (LOD) and quantification (LOQ) were 1.62 ng/mL and 4.85 ng/mL, respectively. The repeatability of the method at a concentration level of the analyte as low as 3 ng/mL, expressed as RSD is 3.5% (n = 6). Recovery was determined using certified reference material: Virginia Tobacco Leaves (CTA-VTL-2). The recovery of zinc ranged from 96.6 to 106.5%. The proposed method was successfully applied for determination of zinc in bee products (honey, propolis and diet supplements) after digestion procedure.

  7. Nationwide residues of mercury, lead, cadmium, arsenic, and selenium in starlings, 1973

    USGS Publications Warehouse

    White, D.H.; Bean, J.R.; Longcore, J.R.

    1977-01-01

    Starlings (Sturnus vulgaris) collected in 1973 at 51 sites throughout the continental United States were analyzed for mercury, lead, cadmium, arsenic, and selenium. All samples contained detectable levels of these elements. In general, residues were low: mercury residues ranged from <0.01 to 0.20 ppm: lead, from <0.10 10 3.20 ppm: cadmium, from <0.05 to 0.20 ppm: arsenic, from <0.05 to 1.40 ppm: and selenium, from 0.10 to 1.10 ppm. There was a significant overall decline in mercury and lead residues in starlings since 1971, and a significant increase in arsenic residues. Lead residues were significantly higher in starlings from urban areas than from rural areas.

  8. Histochemical detection of lead and zinc in plant tissues

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tung, G.; Temple, P.J.

    1975-01-01

    Histochemical studies on uptake and localization of lead and zinc in plant tissues were carried out. A histochemical stain technique was developed to differentiate zinc from lead. Lead was detected in plant tissues by soaking fresh plant materials in freshly prepared sodium rhodizonate stain (0.2% Na rhodizonate acidified to pH3 with glacial acetic acid). Samples were evacuated 5 min and soaked for 30 min before embedding in the congealed stain, then sectioned with a cryostat and examined under a light microscope. Lead particles in plant tissues were stained scarlet-red. Gelatinous, proteinaceous or saccharic embedding materials normally used to prepare plantmore » sampled for sectioning in the cryostat interfered with the color reaction. Sectioning plant samples without staining whole tissues resulted in a weakened response to the stain. Color of stained sample materials were retained for several months if stored in a frozen condition. This technique was used to detect lead both inside and on the surface of plant samples collected in the vicinity of highway and industrial lead sources and to trace the pathways of lead uptake from the air or from contaminated soils. A sodium rhodizonate technique was also developed to be specific for zinc in plant tissues. Plant samples were soaked in a neutral Na-rhodizonate in phosphate buffer at pH 7.5 for observation. The color of zinc developed to produce a purplish or reddish-brown color.« less

  9. Remediation of arsenic and lead with nanocrystalline zinc sulfide.

    PubMed

    Piquette, Alan; Cannon, Cody; Apblett, Allen W

    2012-07-27

    Nanocrystalline (1.7 ± 0.3 nm) zinc sulfide with a specific surface area up to 360 m(2) g(-1) was prepared from the thermal decomposition of a single-source precursor, zinc ethylxanthate. Zinc ethylxanthate decomposes to cubic zinc sulfide upon exposure to temperatures greater than or equal to 125 °C. The resulting zinc sulfide was tested as a water impurity extractant. The target impurities used in this study were As(5+), As(3+), and Pb(2+). The reaction of the nanocrystalline ZnS with Pb(2+) proceeds as a replacement reaction where solid PbS is formed and Zn(2+) is released into the aqueous system. Removal of lead to a level of less than two parts per billion is achievable. The results of a detailed kinetics experiment between the ZnS and Pb(2+) are included in this study. Unlike the instance of lead, both As(5+) and As(3+) adsorb on the surface of the ZnS extractant as opposed to an ion-exchange process. An uptake capacity of > 25 mg g(-1) for the removal of As(5+) is possible. The uptake of As(3+) appears to proceed by a slower process than that of the As(5+) with a capacity of nearly 20 mg g(-1). The nanocrystalline zinc sulfide was extremely successful for the removal of arsenic and lead from simulated oil sand tailing pond water.

  10. Copper and zinc content in wild game shot with lead or non-lead ammunition – implications for consumer health protection

    PubMed Central

    Sommerfeld, Christine; Müller-Graf, Christine; Selhorst, Thomas; Greiner, Matthias; Gerofke, Antje; Ulbig, Ellen; Gremse, Carl; Spolders, Markus; Schafft, Helmut; Lahrssen-Wiederholt, Monika

    2017-01-01

    The aim of this study was to examine the contamination of game meat with copper and zinc and establish whether the use of alternative (non-lead) ammunition can lead to higher or unsafe levels of copper and zinc in the meat of roe deer, wild boar and red deer. The research project “Safety of game meat obtained through hunting” (LEMISI) was conducted in Germany with the purpose of examining the entry of lead as well as copper and zinc into the meat of hunted game when using either lead or non-lead ammunition. The outcome of this study shows that the usage of both lead-based ammunition and alternative non-lead ammunition results in the entry of copper and zinc into the edible parts of the game. Using non-lead ammunition does not entail dangerously elevated levels of copper and zinc, so replacing lead ammunition with alternative ammunition does not introduce a further health problem with regard to these metals. The levels of copper and zinc in game meat found in this study are in the range found in previous studies of game. The content of copper and zinc in game meat is also comparable to those regularly detected in meat and its products from livestock (pig, cattle, sheep) for which the mean human consumption rate is much higher. From the viewpoint of consumer health protection, the use of non-lead ammunition does not pose an additional hazard through copper and zinc contamination. A health risk due to the presence of copper and zinc in game meat at typical levels of consumer exposure is unlikely for both types of ammunition. PMID:28934259

  11. Mercury dispersion in soils of an abandoned lead-zinc-silver mine, San Quintín (Spain)

    NASA Astrophysics Data System (ADS)

    Esbrí, José Maria; Martín-Crespo, T.; Gómez-Ortiz, D.; Monescillo, C. I.; Lorenzo, S.; Higueras, P.

    2010-05-01

    The mine considered on this work, namely San Quintín, is a filonian field with hydrothermal ores exploited during almost fifty years (1887-1934), producing 550.000Tm of galena, 550Tm of silver and 5.000 of sphalerite. Some rewashing works of tailings muds was achieved in recent times (1973-1985), including flotation tests of cinnabar ore from Almadén mines. The main problems remaining on the site are an active acid mine drainage (with pH ~ 2) and heavy metal dispersion on soils including gaseous mercury emissions. We present here results of a survey including soils sampling with mercury analysis and other pedological parameters, as well as determinations of mercury inmission in the atmosphere, using a common sampling grid. Analysis of soils samples has been carried out using an atomic absorption spectrometer AMA254, while air determinations were made by the same technique, using a Lumex RA-915+. The maps have been obtained by means of SURFER 8 software, as well as by ArcGIS software, and puts forward dispersion of mercury from cinnabar ore dump (108 ?g×g-1) to nearby soils (0.3 ?g×g-1 at 700 m of distance). The dispersion of mercury vapor exceed WHO level for chronic exposure (200 ng×m-3) in a small area (250 meters from cinnabar dump).

  12. Water hyacinths and alligator weeds for removal of lead and mercury from polluted waters

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Mcdonald, R. C.

    1975-01-01

    Removal of lead and mercury by water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb. was investigated. Water hyacinths demonstrated the ability to remove 0.176 mg of lead and 0.150 mg of mercury per gram of dry plant material from distilled water and river water in a 24-hour period. One acre of water hyacinths is potentially capable of removing 105.6 grams of lead and 90.0 grams of mercury per day. Alligator weeds removed 0.101 mg of lead per gram of dry plant material in a 24-hour period. This same plant also demonstrated the ability to remove a minimum of 0.153 mg of mercury per gram of dry plant material in a six hour period.

  13. Water hyacinths and alligator weeds for removal of lead and mercury from polluted waters

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wolverton, B.C.; McDonald, R.C.

    1975-04-11

    Removal of lead and mercury by water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb. was investigated. Water hyacinths demonstrated the ability to remove 0.176 mg of lead and 0.150 mg of mercury per gram of dry plant material from distilled water and river water in a 24-hour period. One acre of water hyacinths is potentially capable of removing 105.6 grams of lead and 90.0 grams of mercury per day. Alligator weeds removed 0.101 mg of lead per gram of dry plant material in a 24-hour period. This same plant also demonstrated the ability to removemore » a minimum of 0.153 mg of mercury per gram of dry plant material in a six hour period. (STAR)« less

  14. 25 CFR 215.25 - Other minerals and deep-lying lead and zinc minerals.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Other minerals and deep-lying lead and zinc minerals. 215... LEAD AND ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.25 Other minerals and deep-lying lead and zinc minerals. Except as provided in § 215.6(b), leases on Quapaw Indian lands, for mining...

  15. 25 CFR 215.25 - Other minerals and deep-lying lead and zinc minerals.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Other minerals and deep-lying lead and zinc minerals. 215... LEAD AND ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.25 Other minerals and deep-lying lead and zinc minerals. Except as provided in § 215.6(b), leases on Quapaw Indian lands, for mining...

  16. 25 CFR 215.21 - Payment of gross production tax on lead and zinc.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Payment of gross production tax on lead and zinc. 215.21 Section 215.21 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEAD AND ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.21 Payment of gross production tax on lead and zinc. The superintendent of the Quapaw...

  17. 25 CFR 215.21 - Payment of gross production tax on lead and zinc.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Payment of gross production tax on lead and zinc. 215.21 Section 215.21 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEAD AND ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.21 Payment of gross production tax on lead and zinc. The superintendent of the Quapaw...

  18. 25 CFR 215.21 - Payment of gross production tax on lead and zinc.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Payment of gross production tax on lead and zinc. 215.21... ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.21 Payment of gross production tax on lead and zinc. The superintendent of the Quapaw Indian Agency is hereby authorized and directed to pay at the...

  19. 25 CFR 215.21 - Payment of gross production tax on lead and zinc.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Payment of gross production tax on lead and zinc. 215.21... ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.21 Payment of gross production tax on lead and zinc. The superintendent of the Quapaw Indian Agency is hereby authorized and directed to pay at the...

  20. Release of iron, zinc, and lead from common iron construction bars and zinc metallic bars in water solutions and meals.

    PubMed

    Lechtig, Aarón; Lòpez de Romaña, Daniel; Boy, Erick; Vargas, Alejandro; Rosas del Portal, Mauricio; Huaylinos, María Luisa

    2007-12-01

    The use of iron pots has decreased the prevalence of anemia. To investigate the release of iron, zinc, and lead from metallic iron and zinc bars incubated in water and in meals. Iron, zinc, and lead concentrations were measured at different incubation conditions in water and in meals. The iron concentration in water was 1.26 mg/L after incubation with one iron bar at pH 7 and 100 degrees C for 20 minutes and in meals was 0.97 mg per 100 g of wet meals, rich in phytate, cooking at 100 degrees C during 20 minutes. The maximum contents were 7720 mg/L of iron and 1826 mg/L of zinc in vinegar at pH 3 and 20 degrees C after 90 and 32 days, respectively. Lead was released from the bars, but at concentrations well below the upper tolerable limits. In outreach populations, the use of iron and zinc metallic bars in water and meals could contribute to sustainable, very low-cost prevention of iron and zinc deficiencies, and home-fortified vinegar could be used for treatment of both deficiencies. Field trials should be performed to determine the impact that the use of iron and zinc metallic bars in water and meals might have on the iron and zinc status of population groups.

  1. Accumulation of metals in fish from lead-zinc mining areas of southeastern Missouri, USA

    USGS Publications Warehouse

    Schmitt, Christopher J.; Brumbaugh, William G.; May, Thomas W.

    2007-01-01

    The potential effects of proposed lead-zinc mining in an ecologically sensitive area were assessed by studying a nearby mining district that has been exploited for about 30 yr under contemporary environmental regulations and with modern technology. Blood and liver samples representing fish of three species (largescale stoneroller, Campostoma oligolepis, n=91; longear sunfish, Lepomis megalotis, n=105; and northern hog sucker, Hypentelium nigricans, n=20) were collected from 16 sites representing a range of conditions relative to lead-zinc mining and ore beneficiation in southeastern Missouri. Samples were analyzed for lead, zinc, and cadmium, and for a suite of biomarkers (reported in a companion paper). A subset of the hog sucker (n=9) representing three sites were also analyzed for nickel and cobalt. Blood and liver lead concentrations were highly correlated (r=0.84-0.85, P < 0.01) in all three species and were significantly (ANOVA, P < 0.01) greater at sites < 10 km downstream of active lead-zinc mines and mills and in a historical lead-zinc mining area than at reference sites, including a site in the area proposed for new mining. Correlations between blood and liver cadmium concentrations were less evident than for lead but were nevertheless statistically significant (r=0.26-0.69, P < 0.01-0.07). Although blood and liver cadmium concentrations were highest in all three species at sites near mines, within-site variability was greater and mining-related trends were less evident than for lead. Blood and liver zinc concentrations were significantly correlated only in stoneroller (r=0.46, P < 0.01) and mining-related trends were not evident. Concentrations of cobalt and nickel in blood and liver were significantly higher (ANOVA, P < 0.01) at a site near an active mine than at a reference site and a site in the historical lead-zinc mining area. These findings confirm previous studies indicating that lead and other metals are released to streams from active lead-zinc

  2. Accumulation of metals in fish from lead-zinc mining areas of southeastern Missouri, USA.

    PubMed

    Schmitt, Christopher J; Brumbaugh, William G; May, Thomas W

    2007-05-01

    The potential effects of proposed lead-zinc mining in an ecologically sensitive area were assessed by studying a nearby mining district that has been exploited for about 30 yr under contemporary environmental regulations and with modern technology. Blood and liver samples representing fish of three species (largescale stoneroller, Campostoma oligolepis, n=91; longear sunfish, Lepomis megalotis, n=105; and northern hog sucker, Hypentelium nigricans, n=20) were collected from 16 sites representing a range of conditions relative to lead-zinc mining and ore beneficiation in southeastern Missouri. Samples were analyzed for lead, zinc, and cadmium, and for a suite of biomarkers (reported in a companion paper). A subset of the hog sucker (n=9) representing three sites were also analyzed for nickel and cobalt. Blood and liver lead concentrations were highly correlated (r=0.84-0.85, P<0.01) in all three species and were significantly (ANOVA, P<0.01) greater at sites <10 km downstream of active lead-zinc mines and mills and in a historical lead-zinc mining area than at reference sites, including a site in the area proposed for new mining. Correlations between blood and liver cadmium concentrations were less evident than for lead but were nevertheless statistically significant (r=0.26-0.69, P <0.01-0.07). Although blood and liver cadmium concentrations were highest in all three species at sites near mines, within-site variability was greater and mining-related trends were less evident than for lead. Blood and liver zinc concentrations were significantly correlated only in stoneroller (r=0.46, P<0.01) and mining-related trends were not evident. Concentrations of cobalt and nickel in blood and liver were significantly higher (ANOVA, P<0.01) at a site near an active mine than at a reference site and a site in the historical lead-zinc mining area. These findings confirm previous studies indicating that lead and other metals are released to streams from active lead-zinc mines and

  3. Adsorption characteristics of Copper (Ⅱ), Zinc (Ⅱ) and Mercury (Ⅱ) by four kinds of immobilized fungi residues.

    PubMed

    Li, Xia; Zhang, Dan; Sheng, Fei; Qing, Hui

    2018-01-01

    This study investigated the adsorption characteristics of Copper (Ⅱ), Zinc (Ⅱ) and Mercury (Ⅱ) by immobilized Flammulina velutipes, Auricularia polytricha, Pleurotus eryngii and Pleurotus ostreatus residues. Lagergren model, elovich and intraparticle diffusion model were used to present the adsorption kinetics, and it was proved that Langmuir isotherm model and pseudo-second order kinetics are the best suitable model with high correlation coefficient to characterize the adsorption process of Copper (Ⅱ), Zinc (Ⅱ) and Mercury (Ⅱ). The results showed that adsorption process finished in 120min at pH 6.0. The adsorption rate of Cu 2+ , Zn 2+ and Hg 2+ were reached to 53.8-84.1% of total in the initial 60min, and finished in 120min. Ion exchange and complexation of F. velutipes were the main mechanisms for adsorption of metal ions by characterizations of Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). In addition the functional group of cell walls such as hydroxyl, amide, carbonyl, phosphoric played a critical role in ions adsorption of edible mushroom residues. Cu 2+ , Zn 2+ and Hg 2+ in wastewater could be efficiently removed by F. velutipes residue with removal ratio of 73.11%, 66.67% and 69.35%, respectively. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. 25 CFR 215.25 - Other minerals and deep-lying lead and zinc minerals.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Other minerals and deep-lying lead and zinc minerals. 215.25 Section 215.25 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEAD AND ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.25 Other minerals and deep-lying lead...

  5. 25 CFR 215.25 - Other minerals and deep-lying lead and zinc minerals.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Other minerals and deep-lying lead and zinc minerals. 215.25 Section 215.25 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEAD AND ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.25 Other minerals and deep-lying lead...

  6. 25 CFR 215.25 - Other minerals and deep-lying lead and zinc minerals.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Other minerals and deep-lying lead and zinc minerals. 215.25 Section 215.25 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEAD AND ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.25 Other minerals and deep-lying lead...

  7. Research keeps lead and zinc viable in high-tech markets

    NASA Astrophysics Data System (ADS)

    Cole, Jerome F.

    1989-08-01

    Lead and zinc have long enjoyed widespread use in a variety of applications. To insure growing markets for the future, however, new applications for these durable metals must be developed. Currently, projects are underway to determine the capabilities of lead for such high-technology uses as earthquake damping and nuclear waste containment. Zinc's capabilities are being developed further, too, particularly in the areas of direct injection die casting, composites and the improvement of coating properties. Other ongoing research initiatives are attempting to better determine the health and environmental influences of these metals.

  8. 25 CFR 215.21 - Payment of gross production tax on lead and zinc.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Payment of gross production tax on lead and zinc. 215.21 Section 215.21 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEAD AND ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.21 Payment of gross production tax on lead and...

  9. LEAD AND COPPER CONTROL WITH NON-ZINC ORTHOPHOSPHATE

    EPA Science Inventory

    Successful application of orthophosphate formulations not containing zinc for achieving control of copper and lead corrosion requires careful consideration of the background water chemistry, particularly pH and DIC. Inhibitor performance is extremely dependent upon dosage and pH,...

  10. On the problem of zinc extraction from the slags of lead heat

    NASA Astrophysics Data System (ADS)

    Kozyrev, V. V.; Besser, A. D.; Paretskii, V. M.

    2013-12-01

    The possibilities of zinc extraction from the slags of lead heat are studied as applied to the ZAO Karat-TsM lead plant to be built for processing ore lead concentrates. The process of zinc extraction into commercial fumes using the technology of slag fuming by natural gas developed in Gintsvetmet is recommended for this purpose. Technological rules are developed for designing a commercial fuming plant, as applied to the conditions of the ZAO Karat-TsM plant.

  11. Zinc and lead detoxifying abilities of humic substances relevant to environmental bacterial species.

    PubMed

    Perelomov, L V; Sarkar, Binoy; Sizova, O I; Chilachava, K B; Shvikin, A Y; Perelomova, I V; Atroshchenko, Y M

    2018-04-30

    The effect of humic substances (HS) and their different fractions (humic acids (HA) and hymatomelanic acids (HMA)) on the toxicity of zinc and lead to different strains of bacteria was studied. All tested bacteria demonstrated a lower resistance to zinc than lead showing minimum inhibitory concentrations of 0.1 - 0.3mM and 0.3-0.5mM, respectively. The highest resistance to lead was characteristic of Pseudomonas chlororaphis PCL1391 and Rhodococcus RS67, while Pseudomonas chlororaphis PCL1391 showed the greatest resistance to zinc. The combined fractions of HS and HA alone reduced zinc toxicity at all added concentrations of the organic substances (50 - 200mgL -1 ) to all microorganisms, while hymatomelanic acids reduced zinc toxicity to Pseudomonas chlororaphis PCL1391 at 200mgL -1 organic concentration only. The HS fractions imparted similar effects on lead toxicity also. This study demonstrated that heavy metal toxicity to bacteria could be reduced through complexation with HS and their fractions. This was particularly true when the metal-organic complexes held a high stability, and low solubility and bioavailability. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Mercury Exposure: Protein Biomarkers of Mercury Exposure in Jaraqui Fish from the Amazon Region.

    PubMed

    Vieira, José Cavalcante Souza; Braga, Camila Pereira; de Oliveira, Grasieli; Padilha, Cilene do Carmo Federici; de Moraes, Paula Martin; Zara, Luiz Fabricio; Leite, Aline de Lima; Buzalaf, Marília Afonso Rabelo; Padilha, Pedro de Magalhães

    2018-05-01

    This study presents data on the extraction and characterization of proteins associated with mercury in the muscle and liver tissues of jaraqui (Semaprochilodus spp.) from the Madeira River in the Brazilian Amazon. Protein fractionation was carried out by two-dimensional electrophoresis (2D-PAGE). Mercury determination in tissues, pellets, and protein spots was performed by graphite furnace atomic absorption spectrometry (GFAAS). Proteins in the spots that showed mercury were characterized by electrospray ionization tandem mass spectrometry (ESI-MS/MS). The highest mercury concentrations were found in liver tissues and pellets (426 ± 6 and 277 ± 4 μg kg -1 ), followed by muscle tissues and pellets (132 ± 4 and 86 ± 1 μg kg -1 , respectively). Mercury quantification in the protein spots allowed us to propose stoichiometric ratios in the range of 1-4 mercury atoms per molecule of protein in the protein spots. The proteins characterized in the analysis by ESI-MS/MS were keratin, type II cytoskeletal 8, parvalbumin beta, parvalbumin-2, ubiquitin-40S ribosomal S27a, 39S ribosomal protein L36 mitochondrial, hemoglobin subunit beta, and hemoglobin subunit beta-A/B. The results suggest that proteins such as ubiquitin-40S ribosomal protein S27a, which have specific domains, possibly zinc finger, can be used as biomarkers of mercury, whereas mercury and zinc present characteristics of soft acids.

  13. Toxicity to woodlice of zinc and lead oxides added to soil litter

    USGS Publications Warehouse

    Beyer, W.N.; Anderson, A.

    1985-01-01

    Previous studies have shown that high concentrations of metals in soil are associated with reductions in decomposer populations. We have here determined the relation between the concentrations of lead and zinc added as oxides to soil litter and the survival and reproduction of a decomposer population under controlled conditions. Laboratory populations of woodlice (Porcellio scaber Latr) were fed soil litter treated with lead or zinc at concentrations that ranged from 100 to 12,800 ppm. The survival of the adults, the maximum number of young alive, and the average number of young alive, were recorded over 64 weeks. Lead at 12,800 ppm and zinc at 1,600 ppm or more had statistically significant (p < 0.05) negative effects on the populations. These results agree with field observations suggesting that lead and zinc have reduced populations of decomposers in contaminated forest soil litter, and concentrations are similar to those reported to be associated with reductions in natural populations of decomposers. Poisoning of decomposers may disrupt nutrient cycling, reduce the numbers of invertebrates available to other wildlife for food, and contribute to the contamination of food chains.

  14. An evaluation of airborne nickel, zinc, and lead exposure at hot dip galvanizing plants.

    PubMed

    Verma, D K; Shaw, D S

    1991-12-01

    Industrial hygiene surveys were conducted at three hot dip galvanizing plants to determine occupational exposure to nickel, zinc, and lead. All three plants employed the "dry process" and used 2% nickel, by weight, in their zinc baths. A total of 32 personal and area air samples were taken. The air samples were analyzed for nickel, zinc, and lead. Some samples were also analyzed for various species of nickel (i.e., metallic, soluble, and oxidic). The airborne concentrations observed for nickel and its three species, zinc, and lead at the three plants were all well below the current and proposed threshold limit values recommended by the American Conference of Governmental Industrial Hygienists (ACGIH).

  15. Copper, lead and zinc concentrations of human breast milk as affected by maternal dietary practices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Umoren, J.; Kies, C.

    1986-03-01

    Maternal dietary practices have been found to affect the concentrations of some nutrients in human breast milk. Lead toxicity is a concern in young children. Lead, copper and zinc are thought to compete for intestinal absorption sites. The objective of the current project was to compare copper, lead and zinc contents of breast milk from practicing lacto-vegetarian and omnivore, lactating women at approximately four months post-partum. Analyses were done by atomic absorption spectrophotometry using a carbon rod attachment. Copper concentrations were higher in milk samples from lacto-ovo-vegetarians. Milk samples from the omnivores had the highest lead and zinc concentrations. Leadmore » and copper concentrations in milk were negatively correlated. The higher zinc concentrations in the milk of the omnivore women may have been related to better utilization of zinc from meat than from plant food sources.« less

  16. Atomic absorption spectrometric determination of copper, zinc, and lead in geological materials

    USGS Publications Warehouse

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

    1976-01-01

    An atomic absorption spectrometric method is described for the determination of copper, zinc, and lead in geological materials. The sample is digested with HF-HCl-H2O2; the final solution for analysis is in 10 % (v/v) HCl. Copper and zinc are determined directly by aspirating the solution into an air-acetylene flame. A separate aliquot of the solution is used for determination of lead; lead is extracted into TOPO-MIBK from the acidic solution in the presence of iodide and ascorbic acid. For a 0.50-g sample, the limits of determination are 10-2000 p.p.m. for Cu and Zn, and 5-5000 p.p.m. for Pb. As much as 40 % Fe or Ca. and 10 % Al, Mg, or Mn in the sample do not interfere. The proposed method can be applied to the determination of copper, zinc, and lead in a wide range of geological materials including iron- and manganese-rich, calcareous and carbonate samples. ?? 1976.

  17. Influence of zinc, lead, and cadmium pollutants on the microflora of hawthorn leaves

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bewley, R.J.F.; Campbell, R.

    1980-01-01

    Transect studies were conducted to determine the relative effects of zinc, lead, and cadmium pollution on microorganisms occurring on hawthorn leaves at varying distances from a smelting complex. Sporobolomyces roseus was absent from the most heavily contaminated leaves but, although lead was inhibitory, other environmental factors were also important in determining its overall population level. Conversely, Aureobasidium pullulans and nonpigmented yeasts showed a significant partial positive correlation with lead but were inhibited by zinc and/or cadmium. Numbers of bacterial colonies were only slightly reduced by the combined effect of all three metals, but total numbers of bacteria were highly negativelymore » correlated with lead. Filamentous fungi, isolated by leaf washing, were only slightly inhibited by all three metals, and the degree of mycelial proliferation on senescent leaves was little affected by heavy metal pollution. Computer-generated maps were produced of the distribution of A. pullulans in relation to zinc and lead fallout. 14 references, 7 figures, 2 tables.« less

  18. Environmental pollution levels of lead and zinc in Ishiagu and Uburu communities of Ebonyi State, Nigeria.

    PubMed

    Oje, Obinna A; Uzoegwu, Peter N; Onwurah, Ikechukwu N E; Nwodo, Uchechukwu U

    2010-09-01

    Water and soil samples from the area were therefore analyzed for their lead and zinc content. Computation of pollution statuses of lead and zinc revealed topsoil lead geoaccumulation indices of -0.143 and -0.069 and zinc geoaccumulation indices of 1.168 and 0.713 for Ishiagu and Uburu respectively. The pollution indices were determined to be 0.499 and 0.3564 for soil in Ishiagu and Uburu respectively and also 5.11 and 2.42 for water in Ishiagu and Uburu communities respectively. Water/soil concentration ratio were found to be 0.0018 and 0.0014 for lead in Ishiagu and Uburu respectively. On the other hand, the water/soil concentration ratio for zinc was computed to be 0.001 and 0.0008 for Ishiagu and Uburu respectively. These results seem to suggest that the pollution of the environment by these heavy metals in the areas were as a result of the water being contaminated by lead and zinc not necessarily their concentrations in the soil.

  19. l-Arginine normalizes NOS activity and zinc-MT homeostasis in the kidney of mice chronically exposed to inorganic mercury.

    PubMed

    Piacenza, Francesco; Malavolta, Marco; Cipriano, Catia; Costarelli, Laura; Giacconi, Robertina; Muti, Elisa; Tesei, Silvia; Pierpaoli, Sara; Basso, Andrea; Bracci, Massimo; Bonacucina, Viviana; Santarelli, Lory; Mocchegiani, Eugenio

    2009-09-28

    Inorganic mercury (HgCl2) exposure provokes damage in many organs, especially kidney. Inducible nitric oxide synthase (iNOS) expression, total NOS activity and the profiles of zinc (Zn), copper (Cu) and Hg as well as their distribution when bound to specific intracellular proteins, including metallothioneins (MT), were studied during HgCl2 exposure and after l-arginine treatment in C57BL/6 mouse kidney. HgCl2 exposure modulates differently iNOS expression and NOS activity, increasing iNOS expression but, conversely, decreasing total NOS activity in the mouse kidney. Moreover, during Hg exposure an increased MT production occurs. The kidney damage leads to a loss of urinary proteins, increased plasma creatinine and high Zn mobilization with consequent increased urinary Zn excretion. l-arginine treatment recovers NOS activity and induces a normalization of MT induction, plasma creatinine values and urinary proteins excretion, suggesting that l-arginine may limit kidney damages by Hg exposure.

  20. Increased sensitivity of anodic stripping voltammetry at the hanging mercury drop electrode by ultracathodic deposition.

    PubMed

    Rodrigues, José A; Rodrigues, Carlos M; Almeida, Paulo J; Valente, Inês M; Gonçalves, Luís M; Compton, Richard G; Barros, Aquiles A

    2011-09-09

    An improved approach to the anodic stripping voltammetric (ASV) determination of heavy metals, using the hanging mercury drop electrode (HMDE), is reported. It was discovered that using very cathodic accumulation potentials, at which the solvent reduction occurs (overpotential deposition), the voltammetric signals of zinc(II), cadmium(II), lead(II) and copper(II) increase. When compared with the classical methodology a 5 to 10-fold signal increase is obtained. This effect is likely due to both mercury drop oscillation at such cathodic potentials and added local convection at the mercury drop surface caused by the evolution of hydrogen bubbles. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Lead inhibition of DNA-binding mechanism of Cys(2)His(2) zinc finger proteins.

    PubMed

    Hanas, J S; Rodgers, J S; Bantle, J A; Cheng, Y G

    1999-11-01

    The association of lead with chromatin in cells suggests that deleterious metal effects may in part be mediated through alterations in gene function. To elucidate if and how lead may alter DNA binding of cysteine-rich zinc finger proteins, lead ions were analyzed for their ability to alter the DNA binding mechanism of the Cys(2)His(2) zinc finger protein transcription factor IIIA (TFIIIA). As assayed by DNase I protection, the interaction of TFIIIA with the 50-bp internal control region of the 5S ribosomal gene was partially inhibited by 5 microM lead ions and completely inhibited by 10 to 20 microM lead ions. Preincubation of free TFIIIA with lead resulted in DNA-binding inhibition, whereas preincubation of a TFIIIA/5S RNA complex with lead did not result in DNA-binding inhibition. Because 5S RNA binds TFIIIA zinc fingers, this result is consistent with an inhibition mechanism via lead binding to zinc fingers. The complete loss of DNase I protection on the 5S gene indicates the mechanism of inhibition minimally involves the N-terminal fingers of TFIIIA. Inhibition was not readily reversible and occurred in the presence of an excess of beta-mercaptoethanol. Inhibition kinetics were fast, progressing to completion in approximately 5 min. Millimolar concentrations of sulfhydryl-specific arsenic ions were not inhibitory for TFIIIA binding. Micromolar concentrations of lead inhibited DNA binding by Sp1, another Cys(2)His(2) finger protein, but not by the nonfinger protein AP2. Inhibition of Cys(2)His(2) zinc finger transcription factors by lead ions at concentrations near those known to have deleterious physiological effects points to new molecular mechanisms for lead toxicity in promoting disease.

  2. Survey of mercury, cadmium and lead content of household batteries

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Recknagel, Sebastian, E-mail: sebastian.recknagel@bam.de; Radant, Hendrik; Kohlmeyer, Regina

    2014-01-15

    Highlights: • A well selected sample of 146 batteries was analysed for its heavy metals content. • A comparison was made between heavy metals contents in batteries in 2006 and 2011. • No significant change after implementation of the new EU Batteries Directive. • Severe differences in heavy metal contents were found in different battery-types. - Abstract: The objective of this work was to provide updated information on the development of the potential impact of heavy metal containing batteries on municipal waste and battery recycling processes following transposition of the new EU Batteries Directive 2006/66/EC. A representative sample of 146more » different types of commercially available dry and button cells as well as lithium-ion accumulators for mobile phones were analysed for their mercury (Hg)-, cadmium (Cd)- and lead (Pb)-contents. The methods used for preparing the cells and analysing the heavy metals Hg, Cd, and Pb were either developed during a former study or newly developed. Several batteries contained higher mass fractions of mercury or cadmium than the EU limits. Only half of the batteries with mercury and/or lead fractions above the marking thresholds were labelled. Alkaline–manganese mono-cells and Li-ion accumulators, on average, contained the lowest heavy metal concentrations, while zinc–carbon batteries, on average, contained the highest levels.« less

  3. Exposure of cultured human proximal tubular cells to cadmium, mercury, zinc and bismuth: toxicity and metallothionein induction.

    PubMed

    Rodilla, V; Miles, A T; Jenner, W; Hawksworth, G M

    1998-08-14

    The kidney, in particular the proximal convoluted tubule, is a major target site for the toxic effects of various metals. However, little is known about the early effects of these metals after acute exposure in man. In the present study we have evaluated the toxicity of several inorganic metal compounds (CdCl2, HgCl2, ZnCl2, and Bi(NO3)3) and the induction of metallothionein by these compounds in cultured human proximal tubular (HPT) cells for up to 4 days. The results showed that bismuth was not toxic even at the highest dose (100 microM) used, while zinc, cadmium and mercury exhibited varying degrees of toxicity, zinc being the least toxic and mercury the most potent. A significant degree of interindividual variation between the different isolates used in these experiments was also observed. All metals used in the present study induced MT, as revealed by immunocytochemistry. All metals showed maximal induction between 1 and 3 days after treatment. Although a certain amount of constitutive MT was present in the cultures, the intensity of the staining varied with time in culture and between the different isolates studied. No correlation could be made between the intensity of the staining in control cultures (indicating total amount of constitutive MT) and the susceptibility of a given isolate to metal toxicity. Furthermore, no correlation could be made between metal-induced MT and the susceptibility of a given isolate to that particular metal.

  4. Levels of iron, silver, zinc, and lead in oranges and avocados from two gold-rich towns compared with levels in an adjacent gold-deficient town

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Golow, A.A.; Laryea, J.N.

    1994-09-01

    Fruits such as oranges and avocados are important sources of drinks and food in the Ghanaian Society. If such fruits contain various types of metals they may augument the types and amounts of them in the human body. The metals in fruits may depend on what is in the soils from which they are grown. If the soils contain toxic metals like lead, mercury and cadmium then the consumers may be poisoned as happened in the [open quotes]Ouchi - ouchi[close quotes], disease in Japan and similar episodes. In the area under study, the Geological Survey indicates the presence of 2.5more » ppm of lead, 10 - 20 ppm of copper and less than 15 ppm of nickel. Silver, not reported in commercial amounts, is a byproduct of gold productions at Obuasi. Since copper and nickel are presented in the area traces of silver will certainly occur. In the same manner zinc is usually associated with lead as sulphide of zinc blend trace amounts of it are likely to occur in the area. Of the four metals measured, iron and zinc essential for citrus. The extractable iron and zinc in the area of study were 90 and 1.8 mg/kg, levels on the low side for the healthy growth of crops. The investigation reported here is the comparison of the levels of some metals in oranges and avocados from farms in Obuasi and Konongo with those from farms in Kumasi City. This is a part of a project aimed at finding out differences in the metal contents of various food crops grown in various regions of the country. Konongo and Obuasi have soils which are rich in gold but Kumasi city, which is not too distant from these towns, does not have gold in its soil. 18 refs., 1 tab.« less

  5. [The morphofunctional state of the bone marrow in lead and zinc intoxication].

    PubMed

    Vladimtseva, T M; Pashkevich, I A; Salmina, A B

    2006-01-01

    The nucleolus is a compulsory nuclear structure of all cells of eukaryotes. The quantitative and qualitative characteristics of nuclei show the functional activity of a cell, the rate of its synthesis of RNA and portents, and its metabolic state. Heavy metals (zinc chloride and lead acetate) were comparatively investigated for their effects on the nucleolar apparatus of bone marrow cells in in vivo experiments. Zinc chloride and lead acetate were ascertained to damage the nucleolar apparatus of cells, thus decreasing their transcriptional activity or irreversibly damaging them.

  6. Total arsenic, mercury, lead, and cadmium contents in edible dried seaweed in Korea.

    PubMed

    Hwang, Y O; Park, S G; Park, G Y; Choi, S M; Kim, M Y

    2010-01-01

    Total arsenic, mercury, lead, and cadmium contents were determined in 426 samples of seaweed sold in Korea in 2007-08. The average concentrations, expressed in mg kg(-1), dry weight, were: total arsenic 17.4 (less than the limit of detection [LOD] to 88.8), Hg 0.01 (from 0.001 to 0.050), lead 0.7 (less than the LOD to 2.7), and cadmium 0.50 (less than the LOD to 2.9). There were differences in mercury, cadmium, and arsenic content in seaweed between different kinds of products and between coastal areas. The intakes of total mercury, lead, and cadmium for Korean people from seaweed were estimated to be 0.11, 0.65, and 0.45 µg kg(-1) body weight week(-1), respectively. With respect to food safety, consumption of 8.5 g day(-1) of the samples analysed could represent up to 0.2-6.7% of the respective provisional tolerable weekly intakes established by the World Health Organization (WHO). Therefore, even if Korean people have a high consumption of seaweed, this study confirms the low probability of health risks from these metals via seaweed consumption.

  7. Behavior of lead and zinc in plasma, erythrocytes, and urine and ALAD in erythrocytes following intravenous infusion of CaEDTA in lead workers.

    PubMed

    Araki, S; Aono, H; Fukahori, M; Tabuki, K

    1984-01-01

    To evaluate the effect of calcium disodium ethylenediamine tetraacetate (CaEDTA) on concentrations of lead and zinc in plasma, erythrocytes, whole blood, and urine, we administered CaEDTA by intravenous infusion for 1 hr to seven lead workers with blood lead concentrations of 46-67 micrograms/100 g (mean 54 micrograms/100 g). The plasma lead concentration (PPb) and the mobilization yield of lead in urine by CaEDTA were highest during the period between 1 and 2 hr after the infusion was started. In contrast, the lead concentration in erythrocytes (EPb) and in whole blood (BPb) remained unchanged during the 24 hr following infusion. Plasma zinc concentration (PZn) also fell rapidly following CaEDTA infusion; the decline was followed by a gradual rise in the zinc concentration in erythrocytes (EZn) without alteration in the zinc in whole blood. The mobilization yield of zinc in urine by CaEDTA (MZn) reached its highest level within 1 hr after the start of the infusion. Delta-aminolevulinic acid dehydratase (ALAD) activity in erythrocytes gradually increased for 5 hr following CaEDTA infusion. These observations suggest that (1) PPb concentration is a more sensitive indicator of the body burden of chelatable lead than is either BPb or EPb; (2) MZn is mobilized mostly from plasma during the first several hours following the start of CaEDTA infusion, and the fall in PZn concentration following infusion is compensated first by a rise in EZn concentration and then by an immediate redistribution of zinc in other organs to the blood; and (3) Pb-inhibited ALAD activity is reactivated by the increased EZn during and shortly after CaEDTA infusion.

  8. Low zinc serum levels and high blood lead levels among school-age children in coastal area

    NASA Astrophysics Data System (ADS)

    Pramono, Adriyan; Panunggal, Binar; Rahfiludin, M. Zen; Swastawati, Fronthea

    2017-02-01

    The coverage of environmental lead toxicant was quiet wide. Lead exposure recently has been expected to be associated with zinc deficiency and blood indices disturbance. Emphasizing on children, which could absorb more than 50 % of lead that enters the body. Lead became the issue on the coastal area due to it has polluted the environment and waters as the source of fisheries products. This was a cross sectional study to determined nutritional status, blood lead levels, zinc serum levels, blood indices levels, fish intake among school children in coastal region of Semarang. This study was carried out on the school children aged between 8 and 12 years old in coastal region of Semarang. Nutritional status was figured out using anthropometry measurement. Blood lead and zinc serum levels were analyzed using the Atomic Absorbent Spectrophotometry (AAS) at a wavelength of 213.9 nm for zinc serum and 283.3 nm for blood lead. Blood indices was measured using auto blood hematology analyzer. Fish intake was assessed using 3-non consecutive days 24-hours food recall. The children had high lead levels (median 34.86 μg/dl, range 11.46 - 58.86 μg/dl) compared to WHO cut off. Zinc serum levels was low (median 18.10 μg/dl, range 10.25 - 41.39 μg/dl) compared to the Joint WHO/UNICEF/IAEA/IZiNCG cut off. Approximately 26.4% of children were anemic. This study concluded that all school children had high blood lead levels, low zinc serum, and presented microcytic hypochromic anemia. This phenomenon should be considered as public health concern.

  9. Mercury isotope constraints on the source for sediment-hosted lead-zinc deposits in the Changdu area, southwestern China

    NASA Astrophysics Data System (ADS)

    Xu, Chunxia; Yin, Runsheng; Peng, Jiantang; Hurley, James P.; Lepak, Ryan F.; Gao, Jianfeng; Feng, Xinbin; Hu, Ruizhong; Bi, Xianwu

    2018-03-01

    The Lanuoma and Cuona sediment-hosted Pb-Zn deposits hosted by Upper Triassic limestone and sandstone, respectively, are located in the Changdu area, SW China. Mercury concentrations and Hg isotopic compositions from sulfide minerals and potential source rocks (e.g., the host sedimentary rocks and the metamorphic basement) were investigated to constrain metal sources and mineralization processes. In both deposits, sulfide minerals have higher mercury (Hg) concentrations (0.35 to 1185 ppm) than the metamorphic basement rocks (0.05 to 0.15 ppm) and sedimentary rocks (0.02 to 0.08 ppm). Large variations of mass-dependent fractionation (3.3‰ in δ202Hg) and mass-independent fractionation (0.3‰ in Δ199Hg) of Hg isotopes were observed. Sulfide minerals have Hg isotope signatures that are similar to the hydrothermal altered rocks around the deposit, and similar to the metamorphic basement, but different from barren sedimentary rocks. The variation of Δ199Hg suggests that Hg in sulfides was mainly derived from the underlying metamorphic basement. Mercury isotopes could be a geochemical tracer in understanding metal sources in hydrothermal ore deposits.

  10. Rapid, efficient charging of lead-acid and nickel-zinc traction cells

    NASA Technical Reports Server (NTRS)

    Smithrick, J. J.

    1978-01-01

    Lead-acid and nickel-zinc traction cells were rapidly and efficiently charged using a high rate tapered direct current (HRTDC) charge method which could possibly be used for on-the-road service recharge of electric vehicles. The HRTDC method takes advantage of initial high cell charge acceptance and uses cell gassing rate and temperature as an indicator of charging efficiency. On the average, in these preliminary tests, 300 amp-hour nickel-zinc traction cells were given a HRTDC (initial current 500 amps, final current 100 amps) to 78 percent of rated amp-hour capacity within 53 minutes at an amp-hour efficiency of 92 percent and an energy efficiency of 52 percent. Three hundred amp-hour lead-acid traction cells were charged to 69 percent of rated amp-hour capacity within 46 minutes at an amp-hour efficiency of 91 percent with an energy efficiency of 64 percent. In order to find ways to further decrease the recharge times, the effect of periodically (0 to 400 Hz) pulse discharging cells during a constant current charging process (94% duty cycle) was investigated. Preliminary data indicate no significant effect of this type of pulse discharging during charge on charge acceptance of lead-acid or nickel-zinc cells.

  11. Arsenite binding-induced zinc loss from PARP-1 is equivalent to zinc deficiency in reducing PARP-1 activity, leading to inhibition of DNA repair

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sun, Xi; Zhou, Xixi; Du, Libo

    2014-01-15

    Inhibition of DNA repair is a recognized mechanism for arsenic enhancement of ultraviolet radiation-induced DNA damage and carcinogenesis. Poly(ADP-ribose) polymerase-1 (PARP-1), a zinc finger DNA repair protein, has been identified as a sensitive molecular target for arsenic. The zinc finger domains of PARP-1 protein function as a critical structure in DNA recognition and binding. Since cellular poly(ADP-ribosyl)ation capacity has been positively correlated with zinc status in cells, we hypothesize that arsenite binding-induced zinc loss from PARP-1 is equivalent to zinc deficiency in reducing PARP-1 activity, leading to inhibition of DNA repair. To test this hypothesis, we compared the effects ofmore » arsenite exposure with zinc deficiency, created by using the membrane-permeable zinc chelator TPEN, on 8-OHdG formation, PARP-1 activity and zinc binding to PARP-1 in HaCat cells. Our results show that arsenite exposure and zinc deficiency had similar effects on PARP-1 protein, whereas supplemental zinc reversed these effects. To investigate the molecular mechanism of zinc loss induced by arsenite, ICP-AES, near UV spectroscopy, fluorescence, and circular dichroism spectroscopy were utilized to examine arsenite binding and occupation of a peptide representing the first zinc finger of PARP-1. We found that arsenite binding as well as zinc loss altered the conformation of zinc finger structure which functionally leads to PARP-1 inhibition. These findings suggest that arsenite binding to PARP-1 protein created similar adverse biological effects as zinc deficiency, which establishes the molecular mechanism for zinc supplementation as a potentially effective treatment to reverse the detrimental outcomes of arsenic exposure. - Highlights: • Arsenite binding is equivalent to zinc deficiency in reducing PARP-1 function. • Zinc reverses arsenic inhibition of PARP-1 activity and enhancement of DNA damage. • Arsenite binding and zinc loss alter the conformation of

  12. Concentrations of mercury and other trace elements in walleye, smallmouth bass, and rainbow trout in Franklin D. Roosevelt Lake and the upper Columbia River, Washington, 1994

    USGS Publications Warehouse

    Munn, M.D.; Cox, S.E.; Dean, C.J.

    1995-01-01

    Three species of sportfish--walleye, smallmouth bass, and rainbow trout--were collected from Franklin D. Roosevelt Lake and the upstream reach of the Columbia River within the state of Washington, to determine the concentrations of mercury and other selected trace elements in fish tissue. Concentrations of total mercury in walleye fillets ranged from 0.11 to 0.44 milligram per kilogram, with the higher concentrations in the larger fish. Fillets of smallmouth bass and rainbow trout also contained mercury, but generally at lower concentrations. Other selected trace elements were found in fillet samples, but the concentrations were generally low depending on species and the specific trace element. The trace elements cadmium, copper, lead, and zinc were found in liver tissue of these same species with zinc consistently present in the highest concentration.

  13. 78 FR 46948 - Proposed Agreement Regarding Site Costs and Covenants Not To Sue for American Lead and Zinc Mill...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-02

    ... Not To Sue for American Lead and Zinc Mill Site, Ouray County, Colorado AGENCY: Environmental... provides for Settling Party's payment of certain response costs incurred at the American Lead and Zinc Mill... reference the American Lead and Zinc Mill Site, the EPA Docket No. CERCLA-08-2013- 0004. The Agency's...

  14. Cadmium, lead and mercury levels in feeding yeast produced in Czechoslovakia.

    PubMed

    Cibulka, J; Turecki, T; Miholová, D; Mader, P; Száková, J; Brabec, M

    1992-04-01

    Ninety-six samples of the feeding yeast known as VITEX were analyzed for Cd, Pb and Hg content during 1987-1989. Cadmium content ranged from 0.30 to 5.12 mg/kg(-1), lead content from 0.21 to 3.01 mg/kg(-1) and mercury content from 0.008 to 0.187 mg/kg(-1). Our findings meet the current government standards (max. allowed Pb = 5.00, Cd = 0.50 and Hg = 0.100 mg/kg(-1)) only for lead, and with five exceptions, for mercury. With two exceptions, all cadmium levels found in the samples exceeded the limit. One raw material - the wood chips - was shown to be the main source of cadmium in the technological process. Relatively high Hg contents were measured in the wood chips (up to 0.155 mg/kg(-1)); the highest Hg level (1.105 mg/kg(-1)) however was found in a sample of KOH.

  15. Arsenic, lead, mercury and cadmium: Toxicity, levels in breast milk and the risks for breastfed infants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rebelo, Fernanda Maciel

    Metals are ubiquitous in nature, being found in all environmental compartments, and have a variety of applications in human activities. Metals are transferred by maternal blood to the fetus via the placenta, and exposure continues throughout life. For the general population, exposure comes mainly from water and food consumption, including breast milk. In this paper, we reviewed studies on the toxicity of arsenic, lead, mercury and cadmium, the toxic metals of most concern to human health, focusing on the potential risks to newborns and infants. A total of 75 studies published since 2000 reporting the levels of these metals inmore » breast milk were reviewed. Lead was the metal most investigated in breast milk (43 studies), and for which the highest levels were reported (up to 1515 µg/L). Arsenic was the least investigated (18 studies), with higher levels reported for breast milk (up to 149 µg/L) collected in regions with high arsenic concentrations in water (>10 µg/L). Data from 34 studies on mercury showed that levels in breast milk were generally higher in populations with high fish consumption, where it may be present mainly as MeHg. Cadmium levels in breast milk were the lowest, with means <2 µg/L in most of the 29 studies reviewed. Results of risk assessments indicated that the intake of arsenic, lead and mercury by infants through breastfeeding can be considered a health concern in most regions of the world. Although the potential risks to infants are mostly outweighed by the benefits of breast milk consumption, it is essential that contaminants be continuously monitored, especially in the most critical regions, and that measures be implemented by health authorities to reduce exposure of newborns and infants to these metals, and thus avoid unnecessary health risks. - Highlights: • Review of 75 studies that analyzed arsenic, lead, mercury and/or cadmium levels. • Higher levels of arsenic found in India; of mercury found in Brazil. • Lead was the

  16. Zinc, iron, and lead: relations to head start children's cognitive scores and teachers' ratings of behavior.

    PubMed

    Hubbs-Tait, Laura; Kennedy, Tay Seacord; Droke, Elizabeth A; Belanger, David M; Parker, Jill R

    2007-01-01

    The objective of this study was to conduct a preliminary investigation of lead, zinc, and iron levels in relation to child cognition and behavior in a small sample of Head Start children. The design was cross-sectional and correlational. Participants were 42 3- to 5-year-old children attending rural Head Start centers. Nonfasting blood samples of whole blood lead, plasma zinc, and ferritin were collected. Teachers rated children's behavior on the California Preschool Social Competency Scale, Howes' Sociability subscale, and the Preschool Behavior Questionnaire. Children were tested individually with the McCarthy Scales of Children's Abilities. Hierarchical regression analyses revealed that zinc and ferritin jointly explained 25% of the variance in McCarthy Scales of Children's Abilities verbal scores. Lead levels explained 25% of the variance in teacher ratings of girls' sociability and 20% of the variance in teacher ratings of girls' classroom competence. Zinc levels explained 39% of the variance in teacher ratings of boys' anxiety. Univariate analysis of variance revealed that the four children low in zinc and iron had significantly higher blood lead (median=0.23 micromol/L [4.73 microg/dL]) than the 31 children sufficient in zinc or iron (median=0.07 micromol/L [1.54 microg/dL]) or the 7 children sufficient in both (median=0.12 micromol/L [2.52 microg/dL]), suggesting an interaction among the three minerals. Within this small low-income sample, the results imply both separate and interacting effects of iron, zinc, and lead. They underscore the importance of studying these three minerals in larger samples of low-income preschool children to make more definitive conclusions.

  17. Convective forcing of mercury and ozone in the Arctic boundary layer induced by leads in sea ice.

    PubMed

    Moore, Christopher W; Obrist, Daniel; Steffen, Alexandra; Staebler, Ralf M; Douglas, Thomas A; Richter, Andreas; Nghiem, Son V

    2014-02-06

    The ongoing regime shift of Arctic sea ice from perennial to seasonal ice is associated with more dynamic patterns of opening and closing sea-ice leads (large transient channels of open water in the ice), which may affect atmospheric and biogeochemical cycles in the Arctic. Mercury and ozone are rapidly removed from the atmospheric boundary layer during depletion events in the Arctic, caused by destruction of ozone along with oxidation of gaseous elemental mercury (Hg(0)) to oxidized mercury (Hg(II)) in the atmosphere and its subsequent deposition to snow and ice. Ozone depletion events can change the oxidative capacity of the air by affecting atmospheric hydroxyl radical chemistry, whereas atmospheric mercury depletion events can increase the deposition of mercury to the Arctic, some of which can enter ecosystems during snowmelt. Here we present near-surface measurements of atmospheric mercury and ozone from two Arctic field campaigns near Barrow, Alaska. We find that coastal depletion events are directly linked to sea-ice dynamics. A consolidated ice cover facilitates the depletion of Hg(0) and ozone, but these immediately recover to near-background concentrations in the upwind presence of open sea-ice leads. We attribute the rapid recoveries of Hg(0) and ozone to lead-initiated shallow convection in the stable Arctic boundary layer, which mixes Hg(0) and ozone from undepleted air masses aloft. This convective forcing provides additional Hg(0) to the surface layer at a time of active depletion chemistry, where it is subject to renewed oxidation. Future work will need to establish the degree to which large-scale changes in sea-ice dynamics across the Arctic alter ozone chemistry and mercury deposition in fragile Arctic ecosystems.

  18. Cadmium, lead, and mercury levels in feathers of small passerine birds: noninvasive sampling strategy.

    PubMed

    Bianchi, Nicola; Ancora, Stefania; di Fazio, Noemi; Leonzio, Claudio

    2008-10-01

    Bird feathers have been widely used as a nondestructive biological material for monitoring heavy metals. Sources of metals taken up by feathers include diet (metals are incorporated during feather formation), preening, and direct contact with metals in water, air, dust, and plants. In the literature, data regarding the origin of trace elements in feathers are not univocal. Only in the vast literature concerning mercury (as methyl mercury) has endogenous origin been determined. In the present study, we investigate cadmium, lead, and mercury levels in feathers of prey of Falco eleonorae in relation to the ecological characteristics (molt, habitat, and contamination by soil) of the different species. Cluster analysis identified two main groups of species. Differences and correlations within and between groups identified by cluster analysis were then checked by nonparametric statistical analysis. The results showed that mercury levels had a pattern significantly different from those of cadmium and lead, which in turn showed a significant positive correlation, suggesting different origins. Nests of F. eleonorae proved to be a good source for feathers of small trans-Saharan passerines collected by a noninvasive method. They provided abundant feathers of the various species in a relatively small area--in this case, the falcon colony on the Isle of San Pietro, Sardinia, Italy.

  19. Subacute effects of low dose lead nitrate and mercury chloride exposure on kidney of rats.

    PubMed

    Apaydın, Fatma Gökçe; Baş, Hatice; Kalender, Suna; Kalender, Yusuf

    2016-01-01

    Lead nitrate and mercury chloride are the most common heavy metal pollutants. In the present study, the effects of lead and mercury induced nephrotoxicity were studied in Wistar rats. Lead nitrate (LN, 45 mg/kg b.w/day) and mercury chloride (MC, 0.02 mg/kg b.w/day) and their combination were administered orally for 28 days. Four groups of rats were used in the study: control, LN, MC and LN plus MC groups. Serum biochemical parameters, lipid peroxidation, antioxidant enzymes and histopathological changes in kidney tissues were investigated in all treatment groups. LN and MC caused severe histopathological changes. It was shown that LN, MC and also co-treatment with LN and MC exposure induced significant increase in serum urea, uric acid and creatinine levels. There were also statistically significant changes in antioxidant enzyme activities (SOD, CAT, GPx and GST) and lipid peroxidation (MDA) in all groups except control group. In this study, we showed that MC caused more harmful effects than LN in rats. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Adsorption by and artificial release of zinc and lead from porous concrete for recycling of adsorbed zinc and lead and of porous concrete to reduce urban non-point heavy metal runoff.

    PubMed

    Harada, Shigeki; Yanbe, Miyu

    2018-04-01

    This report describes the use of porous concrete at the bottom of a sewage trap to prevent runoff of non-point heavy metals into receiving waters, and, secondarily, to reduce total runoff volume during heavy rains in urbanized areas while simultaneously increasing the recharge volume of heavy-metal-free water into underground aquifers. This idea has the advantage of preventing clogging, which is fundamentally very important when using pervious materials. During actual field experiments, two important parameters were identified: maximum adsorption weight of lead and zinc by the volume of porous concrete, and heavy metal recovery rate by artificial acidification after adsorption. To understand the effect of ambient heavy metal concentration, a simple mixing system was used to adjust the concentrations of lead and zinc solutions. The concrete blocks used had been prepared for a previous study by Harada & Komuro (2010). The results showed that maximum adsorption depended on the ambient concentration, expressed as the linear isothermal theory, and that recovery depended on the final pH value (0.5 or 0.0). The dependence on pH is very important for recycling the porous concrete. A pH of 0.5 is important for recycling both heavy metals, especially zinc, (8.0-22.1% of lead and 42-74% of zinc) and porous concrete because porous concrete has not been heavily damaged by acid. However, at a pH of 0.0, the heavy metals could be recovered: 30-60% of the lead and 75-125% of the zinc. At a higher pH, such as 2.0, no release of heavy metals occurred, indicating the safety to the environment of using porous concrete, because the lowest recorded pH of rainfall in Japan is. 4.0. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Main and interaction effects of iron, zinc, lead, and parenting on children's cognitive outcomes.

    PubMed

    Hubbs-Tait, Laura; Mulugeta, Afework; Bogale, Alemtsehay; Kennedy, Tay S; Baker, Eric R; Stoecker, Barbara J

    2009-01-01

    This study examined relations of blood lead < 10 microg/dL, iron, zinc, and parenting to Head Start children's (N = 112) scores on Peabody Picture Vocabulary Test-III (PPVT-III) and McCarthy Scales of Children's Abilities (MSCA). Venous whole blood and plasma samples were analyzed for lead and zinc by ICP-MS and iron status was assessed by serum transferrin receptors. Hierarchical regressions revealed significant effects of lead on MSCA perceptual scores and iron on PPVT-III and MSCA verbal scores. Children with lead > 2.5 microg/dL had significantly lower MSCA perceptual scores than children < 2.5 microg/dL. Permissive parenting significantly exacerbated negative effects of higher lead or lower iron on children's perceptual or verbal scores, respectively.

  2. Source identification and mass balance studies of mercury in Lake An-dong, S. Korea

    NASA Astrophysics Data System (ADS)

    Han, J.; Byeon, M.; Yoon, J.; Park, J.; Lee, M.; Huh, I.; Na, E.; Chung, D.; Shin, S.; Kim, Y.

    2009-12-01

    In this study, mercury and methylmercury were measured in atmospheric, tributary, open-lake water column, sediment, planktons and fish samples in the catchments area of Lake An-dong, S. Korea. Lake An-dong, an artificial freshwater lake is located on the upstream of River Nak-dong. It has 51.5 km2 of open surface water and 1.33 year of hydraulic residence time. It is a source of drinking water for 0.3 million S. Koreans. Recently, the possibilities of its mercury contamination became an issue since current studies showed that the lake had much higher mercury level in sediment and certain freshwater fish species than any other lakes in S. Korea. This catchments area has the possibilities of historical mercury pollution by the location of more than 50 abandoned gold mines and Young-poong zinc smelter. The objective of this study was to develop a mercury mass balance and identify possible mercury sources in the lake. The results of this study are thus expected to offer valuable insights for the sources of mercury loading through the watershed. In order to estimate the mercury flux, TGM, RGM and particulate mercury were measured using TEKRAN 2537 at the five sites surrounding Lake An-dong from May, 2009 with wet and dry deposition. The fate and transport of mercury in water body were predicted by using EFDC (Environmental Dynamic Fluid Code) and Mercury module in WASP7 (Water quality analysis program) after subsequent distribution into water body, sediments, followed by bioaccumulation and ultimate uptake by humans. The mercury mass balance in Young-poong zinc smelter was also pre-estimated by measuring mercury content in zinc ores, emission gases, sludge, wastewater and products.

  3. 40 CFR 437.44 - Effluent limitations attainable by the application of the best available technology economically...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Antimony Arsenic Cadmium Chromium Cobalt Copper Lead Mercury Nickel Silver Tin Titanium Vanadium Zinc (2... Lead Mercury Nickel Silver Tin Titanium Vanadium Zinc (2) The in-plant limitations that apply to metal... parameters Antimony Arsenic Cadmium Chromium Cobalt Copper Lead Mercury Nickel Silver Tin Titanium Vanadium...

  4. 40 CFR 437.44 - Effluent limitations attainable by the application of the best available technology economically...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Antimony Arsenic Cadmium Chromium Cobalt Copper Lead Mercury Nickel Silver Tin Titanium Vanadium Zinc (2... Lead Mercury Nickel Silver Tin Titanium Vanadium Zinc (2) The in-plant limitations that apply to metal... parameters Antimony Arsenic Cadmium Chromium Cobalt Copper Lead Mercury Nickel Silver Tin Titanium Vanadium...

  5. 40 CFR 437.44 - Effluent limitations attainable by the application of the best available technology economically...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Antimony Arsenic Cadmium Chromium Cobalt Copper Lead Mercury Nickel Silver Tin Titanium Vanadium Zinc (2... Lead Mercury Nickel Silver Tin Titanium Vanadium Zinc (2) The in-plant limitations that apply to metal... parameters Antimony Arsenic Cadmium Chromium Cobalt Copper Lead Mercury Nickel Silver Tin Titanium Vanadium...

  6. 40 CFR 437.44 - Effluent limitations attainable by the application of the best available technology economically...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Antimony Arsenic Cadmium Chromium Cobalt Copper Lead Mercury Nickel Silver Tin Titanium Vanadium Zinc (2... Lead Mercury Nickel Silver Tin Titanium Vanadium Zinc (2) The in-plant limitations that apply to metal... parameters Antimony Arsenic Cadmium Chromium Cobalt Copper Lead Mercury Nickel Silver Tin Titanium Vanadium...

  7. 40 CFR 437.44 - Effluent limitations attainable by the application of the best available technology economically...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Antimony Arsenic Cadmium Chromium Cobalt Copper Lead Mercury Nickel Silver Tin Titanium Vanadium Zinc (2... Lead Mercury Nickel Silver Tin Titanium Vanadium Zinc (2) The in-plant limitations that apply to metal... parameters Antimony Arsenic Cadmium Chromium Cobalt Copper Lead Mercury Nickel Silver Tin Titanium Vanadium...

  8. Biomarkers of metals exposure in fish from lead-zinc mining areas of Southeastern Missouri, USA

    USGS Publications Warehouse

    Schmitt, C.J.; Whyte, J.J.; Roberts, A.P.; Annis, M.L.; May, T.W.; Tillitt, D.E.

    2007-01-01

    The potential effects of proposed lead-zinc mining in an ecologically sensitive area were assessed by studying a nearby mining district that has been exploited for about 30 y under contemporary environmental regulations and with modern technology. Blood and liver samples representing fish of three species (largescale stoneroller, Campostoma oligolepis, n=91; longear sunfish, Lepomis megalotis, n=105; and northern hog sucker, Hypentelium nigricans, n=20) from 16 sites representing a range of conditions relative to mining activities were collected. Samples were analyzed for metals (also reported in a companion paper) and for biomarkers of metals exposure [erythrocyte ??-aminolevulinic acid dehydratase (ALA-D) activity; concentrations of zinc protoporphyrin (ZPP), iron, and hemoglobin (Hb) in blood; and hepatic metallothionein (MT) gene expression and lipid peroxidation]. Blood lead concentrations were significantly higher and ALA-D activity significantly lower in all species at sites nearest to active lead-zinc mines and in a stream contaminated by historical mining than at reference or downstream sites. ALA-D activity was also negatively correlated with blood lead concentrations in all three species but not with other metals. Iron and Hb concentrations were positively correlated in all three species, but were not correlated with any other metals in blood or liver in any species. MT gene expression was positively correlated with liver zinc concentrations, but neither MT nor lipid peroxidase differences among fish grouped according to lead concentrations were statistically significant. ZPP was not detected by hematofluorometry in most fish, but fish with detectable ZPP were from sites affected by mining. Collectively, these results confirm that metals are released to streams from active lead-zinc mining sites and are accumulated by fish. ?? 2007 Elsevier Inc. All rights reserved.

  9. Evidence of transboundary mercury and other pollutants in the Puyango-Tumbes River basin, Ecuador-Peru.

    PubMed

    Marshall, Bruce G; Veiga, Marcello M; Kaplan, Robert J; Adler Miserendino, Rebecca; Schudel, Gary; Bergquist, Bridget A; Guimarães, Jean R D; Sobral, Luis G S; Gonzalez-Mueller, Carolina

    2018-04-25

    In Portovelo in southern Ecuador, 87 gold processing centers along the Puyango-Tumbes River produce an estimated 6 tonnes of gold per annum using a combination of mercury amalgamation and/or cyanidation and processing poly-metallic ores. We analysed total Hg, Hg isotopes, total arsenic, cadmium, copper, lead and zinc in water and sediment along the Puyango in 2012-2014. The highest total mercury (THg) concentrations in sediments were found within a 40 km stretch downriver from the processing plants, with levels varying between 0.78-30.8 mg kg-1 during the dry season and 1.80-70.7 mg kg-1 during the wet season, with most concentrations above the CCME (Canadian Council of Ministers of the Environment) Probable Effect Level (PEL) of 0.5 mg kg-1. Data from mercury isotopic analyses support the conclusion that mercury use during gold processing in Portovelo is the source of Hg pollution found downstream in the Tumbes Delta in Peru, 160 km away. The majority of the water and sediment samples collected from the Puyango-Tumbes River had elevated concentrations of, arsenic, cadmium, copper, lead and zinc exceeding the CCME thresholds for the Protection of Aquatic Life. At monitoring points immediately below the processing plants, total dissolved concentrations of these metals exceeded the thresholds by 156-3567 times in surface waters and by 19-740 times in sediment. The results illustrate a significant transboundary pollution problem involving Hg and other toxic metals, amplified by the fact that the Puyango-Tumbes River is the only available water source in the semi-arid region of northern Peru.

  10. Assessment of Hair Aluminum, Lead, and Mercury in a Sample of Autistic Egyptian Children: Environmental Risk Factors of Heavy Metals in Autism.

    PubMed

    Mohamed, Farida El Baz; Zaky, Eman Ahmed; El-Sayed, Adel Bassuoni; Elhossieny, Reham Mohammed; Zahra, Sally Soliman; Salah Eldin, Waleed; Youssef, Walaa Yousef; Khaled, Rania Abdelmgeed; Youssef, Azza Mohamed

    2015-01-01

    The etiological factors involved in the etiology of autism remain elusive and controversial, but both genetic and environmental factors have been implicated. The aim of this study was to assess the levels and possible environmental risk factors and sources of exposure to mercury, lead, and aluminum in children with autism spectrum disorder (ASD) as compared to their matched controls. One hundred ASD children were studied in comparison to 100 controls. All participants were subjected to clinical evaluation and measurement of mercury, lead, and aluminum through hair analysis which reflects past exposure. The mean Levels of mercury, lead, and aluminum in hair of the autistic patients were significantly higher than controls. Mercury, lead, and aluminum levels were positively correlated with maternal fish consumptions, living nearby gasoline stations, and the usage of aluminum pans, respectively. Levels of mercury, lead, and aluminum in the hair of autistic children are higher than controls. Environmental exposure to these toxic heavy metals, at key times in development, may play a causal role in autism.

  11. Assessment of Hair Aluminum, Lead, and Mercury in a Sample of Autistic Egyptian Children: Environmental Risk Factors of Heavy Metals in Autism

    PubMed Central

    Mohamed, Farida El Baz; Zaky, Eman Ahmed; El-Sayed, Adel Bassuoni; Elhossieny, Reham Mohammed; Zahra, Sally Soliman; Salah Eldin, Waleed; Youssef, Walaa Yousef; Khaled, Rania Abdelmgeed; Youssef, Azza Mohamed

    2015-01-01

    Background and Aims. The etiological factors involved in the etiology of autism remain elusive and controversial, but both genetic and environmental factors have been implicated. The aim of this study was to assess the levels and possible environmental risk factors and sources of exposure to mercury, lead, and aluminum in children with autism spectrum disorder (ASD) as compared to their matched controls. Methods. One hundred ASD children were studied in comparison to 100 controls. All participants were subjected to clinical evaluation and measurement of mercury, lead, and aluminum through hair analysis which reflects past exposure. Results. The mean Levels of mercury, lead, and aluminum in hair of the autistic patients were significantly higher than controls. Mercury, lead, and aluminum levels were positively correlated with maternal fish consumptions, living nearby gasoline stations, and the usage of aluminum pans, respectively. Conclusion. Levels of mercury, lead, and aluminum in the hair of autistic children are higher than controls. Environmental exposure to these toxic heavy metals, at key times in development, may play a causal role in autism. PMID:26508811

  12. Temporal and spatial variations of copper, cadmium, lead, and zinc in Ten Mile Creek in South Florida, USA.

    PubMed

    Yang, Yuangen; He, Zhenli; Lin, Youjian; Phlips, Edward J; Stoffella, Peter J; Powell, Charles A

    2009-01-01

    Lead (Pb), zinc (Zn), copper (Cu), and cadmium (Cd) often seriously deteriorate water quality. Spatial and temporal fluctuations of the metal concentrations in the Ten Mile Creek (Florida) (TMC) were monitored on a weekly basis at 7 sampling sites, from June 2005 to September 2007. River sediment samples were also collected from these sites in April, June, and October 2006 and January 2007, and analyzed for water, Mehlich 1 (M1), and Mehlich 3 (M3)-extractable metals (Mehlich, 1953, 1984), to examine the role of sediments as sources or sinks of the metals. The concentrations of lead, zinc, copper, and cadmium in the water samples were lead (zinc (6.45 microg/L), copper (2.53 microg/L), and cadmium (lead, 120 microg/L for zinc, 9.0 microg/L for copper, and 0.25 microg/L for cadmium), pulse concentrations of the metals significantly exceeded these limits. Correlations of lead, zinc, copper, and cadmium concentrations in the TMC to other environmental factors, including the results of principal component analysis, suggest that there are different sources of metals. These sources include surface runoff from agricultural lands or urban wastewater, geological backgrounds, and tidal flow. Water-, M1-, and M3-extractable lead, zinc, copper, and cadmium concentrations in river sediments indicate the possibility that river sediment serves as an internal source of the metals for the TMC. This hypothesis was supported by positive correlations between concentrations of copper, lead, and zinc in the river water and their respective water-extractable concentrations in the sediments.

  13. Lead and mercury levels in an environmentally exposed population in the Central Brazil.

    PubMed

    Jesus, Leda Diva Freitas de; Moreira, Maria de Fátima Ramos; Azevedo, Sayonara Vieira de; Borges, Renato Marçullo; Gomes, Regina Aderne de Almeida; Bergamini, Fernanda Pereira Baptista; Teixeira, Liliane Reis

    2018-03-01

    The objective was to assess the level of exposure to lead and mercury in a population in the Pantanal region in Mato Grosso State, Brazil. Blood lead (PbB) (n = 119) and urinary mercury (HgU) (n = 109) in local residents were measured by atomic absorption spectrometry. Comparison of means and correlations between variables used analysis of variance (ANOVA) and linear regression, respectively, with 95% confidence intervals. Mean PbB was 2.82 ± 1.53µg dL-1. The comparison of PbB stratified by collection site (p ≤ 0.01), work activity (p ≤ 0.01), and consumption of locally produced cow's milk (p ≤ 0.05) showed statistically significant differences. There were also positive associations between PbB and collection site (p ≤ 0.01), participants' profession (p ≤ 0.05), local milk (p ≤ 0.01), and source of drinking water (p ≤ 0.01). Mean HgU was 1.41 ± 0.98µg L-1. The levels only showed significant differences for participants' profession (p ≤ 0.01), and positive associations emerged between HgU and work activity (p ≤ 0.01) and body mass index (p ≤ 0.01). The samples showed low lead and mercury levels, similar to those found in other environmentally exposed populations. Despite these low concentrations, current knowledge on the toxicity of these metals shows that health effects can already be felt at levels that were previously considered safe, thus characterizing a health hazard.

  14. Significant deposits of gold, silver, copper, lead, and zinc in the United States

    USGS Publications Warehouse

    Long, K.R.; DeYoung, J.H.; Ludington, S.

    2000-01-01

    Approximately 99 percent of past production and remaining identified resources of gold, silver, copper, lead, and zinc in the United States are accounted for by deposits that originally contained at least 2 metric tonnes (t) gold, 85 t silver, 50,000 t copper, 30,000 t lead, or 50,000 t zinc. The U.S. Geological Survey, beginning with the 1996 National Mineral Resource Assessment, is systematically compiling data on these deposits, collectively known as 'significant' deposits. As of December 31, 1996, the significant deposits database contained 1,118 entries corresponding to individual deposits or mining districts. Maintaining, updating and analyzing a database of this size is much easier than managing the more than 100,000 records in the Mineral Resource Data System and Minerals Availability System/Minerals Industry Location System, yet the significant deposits database accounts for almost all past production and remaining identified resources of these metals in the United States. About 33 percent of gold, 22 percent of silver, 42 percent of copper, 39 percent of lead, and 46 percent of zinc are contained in or were produced from deposits discovered after World War II. Even within a database of significant deposits, a disproportionate share of past production and remaining resources is accounted for by a very small number of deposits. The largest 10 producers for each metal account for one third of the gold, 60 percent of the silver, 68 percent of the copper, 85 percent of the lead, and 75 percent of the zinc produced in the United States. The 10 largest deposits in terms of identified remaining resources of each of the five metals contain 43 percent of the gold, 56 percent of the silver, 48 percent of the copper, 94 percent of the lead, and 72 percent of the zinc. Identified resources in significant deposits for each metal are less than the mean estimates of resources in undiscovered deposits from the 1996 U.S. National Mineral Resource Assessment. Identified

  15. The effects of CaEDTA injection on lead, zinc, copper and ALAD in erythrocyte, plasma and urine in lead-exposed workers: a 24-h observation.

    PubMed

    Aono, H; Araki, S

    1984-01-01

    To evaluate the effects of calcium disodium ethylenediamine tetraacetate (CaEDTA) on the concentrations of lead, zinc and copper in plasma, erythrocyte and urine, and the delta-aminolevulinic acid dehydratase (ALAD) activity in erythrocyte, we administered CaEDTA in 1-h intravenous infusion to ten male gun metal founders with blood-lead concentration of 39 to 64 micrograms/dl (mean 49 micrograms/dl). We found that the plasma concentration of lead, following a rapid rise within the first 3 h, fell temporarily to the level significantly lower than the initial level 19 h after start of the infusion. The plasma concentration of zinc fell to the minimal level 5 h after the infusion; and the erythrocyte concentration of zinc and the ALAD activity concurrently rose to the maximal level 5 h after the infusion. By contrast, no significant alteration was observed in the concentrations of copper in plasma and erythrocyte. The maximal level of urinary metal excretion was attained during the period between 1 and 2 h after start of CaEDTA infusion for lead; within 2 h for zinc; and between 2 and 4 h for copper. The urinary metal excretion returned to the initial level 14 to 24 h after infusion for zinc and copper; but lead excretion was still higher than the initial level during this period. The difference in the kinetics of the three metals following CaEDTA injection is discussed in the light of these findings.

  16. Determination of Cadmium, Lead and Zinc in Vegetables in Jaipur (India).

    PubMed

    Kumar, Ashok; Verma, P S

    2014-01-01

    An atomic absorption spectroscopic method was used for the determination of Lead, Cadmium and Zinc in vegetables grown in and around Jaipur food stuffs irrigated with industrial waste water. Vegetable samples were collected after maturity, and analyzed, such as spinach (Spinacia oleracea), ladyfinger (Abelmoschus esulentus), pepper mint (Menthe pipereta), brinjal (Solanum melongena), coriander (Coriandrum sativum), cauliflower (Brassica oleracea), onion (Allium cepa), radish (Raphanus sativus), pointedgourd (Trichosanthes dioica), bottlegourd (Lagenaria siceraria), chilies (Capsicum annum), ribbedgourd (Luffa acutangula) and pumpkin (Curcurbites pepo). The concentration of Lead ranged between 1.40-71.06 ppm, Cadmium 0.61-34.48 ppm and Zinc 0.39-187.26 ppm in vegetable samples. The results reveal that urban consumers are at greater risk of purchasing fresh vegetables with high levels of heavy metal, beyond the permissible limits, as defined by the Indian Prevention of Food Adulteration Act, 1954 and WHO.

  17. Compatibility of structural materials with liquid bismuth, lead, and mercury

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weeks, J.R.

    1996-06-01

    During the 1950s and 1960s, a substantial program existed at Brookhaven National Laboratory as part of the Liquid Metal Fuel reactor program on the compatibility of bismuth, lead, and their alloys with structural materials. Subsequently, compatibility investigations of mercury with structural materials were performed in support of development of Rankine cycle mercury turbines for nuclear applications. The present talk will review present understanding of the corrosion/mass-transfer reactions of structural materials with these liquid metal coolants. Topics to be discussed include the basic solubility relationships of iron, chromium, nickel, and refractory metals in these liquid metals, the results of inhibition studies,more » the role of oxygen on the corrosion processes, and specialized topics such as cavitation-corrosion and liquid metal embrittlement. Emphasis will be placed on utilizing the understanding gained in this earlier work on the development of heavy liquid metal targets in spallation neutron sources.« less

  18. Simultaneous Measurement of Zinc, Copper, Lead and Cadmium in Baby Weaning Food and Powder Milk by DPASV.

    PubMed

    Sadeghi, Naficeh; Oveisi, Mohammad Reza; Jannat, Behrooz; Hajimahmoodi, Mannan; Behfar, Abdolazim; Behzad, Masoomeh; Norouzi, Narges; Oveisi, Morvarid; Jannat, Behzad

    2014-01-01

    Apart from the breast milk, infant formula and baby weaning food have a special role in infant diet. Infants and young children are very susceptible to amount of trace elements. Copper and zinc are two elements that add in infant food. Lead and cadmium are heavy metals that enter to food chain unavoidably. DPASV is a benefit and applicable method for measurement of trace elements in food products. In this study, concentration of zinc, copper, lead and cadmium in four brands of baby food (rice and wheat based) and powder milk was analyzed with DPASV and polarograph set. Total Mean ± SE of zinc, copper, lead and cadmium in baby foods (n = 240) were 11.86 ± 1.474 mg/100g, 508.197 ± 83.154 μg/100g, 0.445 ± 0.006, 0.050 ± 0.005 mg/Kg respectively. Also these amount in powder milk (n = 240) were 3.621± 0.529 mg/100g, 403.822 ± 133.953 μg/100g, 0.007 ± 0.003, 0.060 ± 0.040 mg/Kg respectively. Zinc level in baby food type I was higher than lablled value (P = 0.030), but in other brands was not difference. Concentration of copper in all of samples was in labeled range (P > 0.05). In each four products, level of lead and cadmium were lower than the standard limit (P < 0.05). Amount of zinc and lead in baby food I, had difference versus other products. Concentration of zinc, camium in baby food type I, was higher than type II (P = 0.043, 0.001 respectively). Concentration of lead and cadmium in baby food type II, was higher than infant formulas, but are in standard limit.

  19. Natural Attenuation of Arsenic, Cadmium, Lead, and Zinc Using Hydrograph Separation

    NASA Astrophysics Data System (ADS)

    Burrows, J. E.; Peters, S. C.

    2009-12-01

    Strategies for remediating contaminated sites range from complete removal of the contaminated soil to in-situ monitored natural attenuation. The decision to let a property naturally attenuate is partially based on the estimated time it will take to return to ambient conditions. The Lehigh Gap Wildlife Refuge at Palmerton, PA was historically contaminated with arsenic, cadmium, lead, and zinc from a zinc smelting operation that ceased emissions twenty-nine years ago. This property provides an opportunity to assess whether the length of time required for the natural attenuation of metals in soil has been achieved using a watershed mass balance approach, focusing particularly on perturbations observed in the concentration-discharge relationships of contaminants compared to the conservative tracers sodium and chloride, and silicon as an indicator of rock-water interactions. Water samples were collected from 3 springs in the Wildlife Refuge for approximately 4 days following the onset of storm events and analyzed for cation and anion concentrations. Preliminary results show that while the concentrations of arsenic and lead were below detection limits, the fluxes of zinc and cadmium increase corresponding with the peak in the hydrograph relative to the fluxes of the tracers, indicating the solutes are being released from adsorption sites located in an unsaturated zone that is temporarily inundated during storm events. In comparison, the flux of the tracers remains constant, indicative of a steady-state leakage of the solutes from their respective reservoirs in the soil. Along with flux, the concentrations of zinc and cadmium also increase following the rise in discharge after storm events, further suggesting that these contaminants are being mobilized out of the soil profile.

  20. Single and Combined Exposure to Zinc- and Copper-Containing Welding Fumes Lead to Asymptomatic Systemic Inflammation.

    PubMed

    Markert, Agnieszka; Baumann, Ralf; Gerhards, Benjamin; Gube, Monika; Kossack, Veronika; Kraus, Thomas; Brand, Peter

    2016-02-01

    Recently, it has been shown that exposure to welding fumes containing both zinc and copper leads to asymptomatic systemic inflammation in humans as shown by an increase of blood C-reactive protein. In the present study, it was investigated which metal is responsible for this effect. Fifteen healthy male subjects were exposed under controlled conditions to welding fumes containing either zinc, or copper, or copper and zinc. For each exposure blood C-reactive protein increased. Copper- and zinc-containing welding fumes are able to induce systemic inflammation.

  1. 40 CFR 421.253 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... gold refined electrolytically Lead 5.544 2.574 Mercury 2.970 1.188 Silver 5.742 2.376 Zinc 20.200 8.316... smelted Lead 0.364 0.169 Mercury 0.195 0.078 Silver 0.377 0.156 Zinc 1.326 0.546 Gold 0.130 (b) Silver... reduced in solution Lead 0.112 0.052 Mercury 0.060 0.024 Silver 0.116 0.048 Zinc 0.408 0.168 Gold 0.040 (c...

  2. Metal residues, histopathology and presence of parasites in the liver and gills of fourhorn sculpin (Myoxocephalus quadricornis) and shorthorn sculpin (Myoxocephalus scorpius) near a former lead-zinc mine in East Greenland

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dang, Mai

    Fourhorn sculpins (Myoxocephalus quadricornis) and shorthorn sculpins (Myoxocephalus scorpius) have been considered suitable local bioindicators for environmental monitoring studies in the Arctic. Because these species share many characteristics, data from the two species have previously been pooled when assessing marine metal contamination. A chemical and histological study was conducted on fourhorn and shorthorn sculpins collected around a contaminated lead-zinc mine at East Greenland to investigate whether there were any differences in the residues of metals, histopathology and parasites in liver and gills between the two sculpin species. The results demonstrated that concentrations of copper (Cu), zinc (Zn), mercury (Hg) andmore » lead (Pb) were significantly higher in the fourhorn sculpins (p<0.001) while there were no significant differences for arsenic (As) or cadmium (Cd). Furthermore, density of blood vessel fibrosis (p=0.028), prevalence and density of chondroplasia (p=0.002 and p=0.005, respectively), number of mucin-containing mucous cells (p<0.001) and chloride cells (p<0.001) and mean intensity of colonial Peritricha (p<0.001) were significantly higher in fourhorn sculpin. Based on these results we suggest that pooling the two species when conducting environmental assessments is not recommended as it can lead to incorrect conclusions. We propose that a larger study investigating the biological effects of zinc-lead mining in Greenland is needed. - Highlights: • Fourhorn sculpins (Myoxocephalus quadricornis) more sensitive to pollution than shorthorn sculpins (Myoxocephalus scorpius). • Metal residues, histological changes and presence of parasites were species-specific. • Different sculpin species should not be pooled together as pollution biomarkers.« less

  3. Occurrence and variability of mining-related lead and zinc in the Spring River flood plain and tributary flood plains, Cherokee County, Kansas, 2009--11

    USGS Publications Warehouse

    Juracek, Kyle E.

    2013-01-01

    Historical mining activity in the Tri-State Mining District (TSMD), located in parts of southeast Kansas, southwest Missouri, and northeast Oklahoma, has resulted in a substantial ongoing input of cadmium, lead, and zinc to the environment. To provide some of the information needed to support remediation efforts in the Cherokee County, Kansas, superfund site, a 4-year study was begun in 2009 by the U.S. Geological Survey that was requested and funded by the U.S. Environmental Protection Agency. A combination of surficial-soil sampling and coring was used to investigate the occurrence and variability of mining-related lead and zinc in the flood plains of the Spring River and several tributaries within the superfund site. Lead- and zinc-contaminated flood plains are a concern, in part, because they represent a long-term source of contamination to the fluvial environment. Lead and zinc contamination was assessed with reference to probable-effect concentrations (PECs), which represent the concentrations above which adverse aquatic biological effects are likely to occur. The general PECs for lead and zinc were 128 and 459 milligrams per kilogram, respectively. The TSMD-specific PECs for lead and zinc were 150 and 2,083 milligrams per kilogram, respectively. Typically, surficial soils in the Spring River flood plain had lead and zinc concentrations that were less than the general PECs. Lead and zinc concentrations in the surficial-soil samples were variable with distance downstream and with distance from the Spring River channel, and the largest lead and zinc concentrations usually were located near the channel. Lead and zinc concentrations larger than the general or TSMD-specific PECs, or both, were infrequent at depth in the Spring River flood plain. When present, such contamination typically was confined to the upper 2 feet of the core and frequently was confined to the upper 6 inches. Tributaries with few or no lead- and zinc-mined areas in the basin—Brush Creek

  4. Lead, cadmium and mercury in the blood of the blue-footed booby (Sula nebouxii) from the coast of Sinaloa, Gulf of California, Mexico.

    PubMed

    Lerma, Miriam; Castillo-Guerrero, José Alfredo; Ruelas-Inzunza, Jorge; Fernández, Guillermo

    2016-09-15

    We used blood samples of the Blue-footed Booby, considering sex (female and male) and age-class (adult and chick) of individuals at different breeding stages during two breeding seasons (2010-2011 and 2011-2012) in Isla El Rancho, Sinaloa, to determine lead, cadmium, and mercury concentrations. Lead and cadmium concentrations were below our detection limit (0.05 and 0.36ppm, respectively). A higher concentration of mercury was found in early stages of breeding, likely related to changes in mercury environmental availability. Mercury concentrations in adults did not relate with their breeding output. Males and adults had higher mercury concentration than females and chicks. We provide information of temporal, sex and age-related variations in the concentrations of mercury in blood of the Blue-footed Booby. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Effects of lead and zinc mining contamination on bacterial community diversity and enzyme activities of vicinal cropland.

    PubMed

    Qu, Juanjuan; Ren, Guangming; Chen, Bao; Fan, Jinghua; E, Yong

    2011-11-01

    In the process of mining activity, many kinds of heavy metals enter into soils with dust, causing serious contamination to the environment. In this study, six soils were sampled from cropland at different distances from a lead/zinc mine in Heilongjiang Province, China. The total contents of lead and zinc in the vicinal cropland exceeded the third level of environmental quality standard for soil in China, which indicated that soils in this area were moderately contaminated. Bacterial community diversity and population were greatly decreased when the concentrations of lead and zinc were beyond 1,500 and 995 mg kg(-1), respectively, as analyzed by plate counting and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The bands of DGGE patterns varied with the degree of contamination. The activities of soil urease, phosphatase, and dehydrogenase were negatively correlated with the concentrations of lead and zinc. The highest inhibitory effect of heavy metals on soil enzyme activities was observed in urease. It was noted that PCR-DGGE patterns combined with soil enzyme activity analysis can be indices for the soil quality assessment by heavy metal contamination.

  6. Cadmium, lead, mercury and arsenic in animal feed and feed materials - trend analysis of monitoring results.

    PubMed

    Adamse, Paulien; Van der Fels-Klerx, H J Ine; de Jong, Jacob

    2017-08-01

    This study aimed to obtain insights into the presence of cadmium, lead, mercury and arsenic in feed materials and feed over time for the purpose of guiding national monitoring. Data from the Dutch feed monitoring programme and from representatives of the feed industry during the period 2007-13 were used. Data covered a variety of feed materials and compound feeds in the Netherlands. Trends in the percentage of samples that exceeded the maximum limit (ML) set by the European Commission, and trends in average, median and 90th percentile concentrations of each of these elements were investigated. Based on the results, monitoring should focus on feed material of mineral origin, feed material of marine origin, especially fish meal, seaweed and algae, as well as feed additives belonging to the functional groups of (1) trace elements (notably cupric sulphate, zinc oxide and manganese oxide for arsenic) and (2) binders and anti-caking agents. Mycotoxin binders are a new group of feed additives that also need attention. For complementary feed it is important to make a proper distinction between mineral and non-mineral feed (lower ML). Forage crops in general do not need high priority in monitoring programmes, although for arsenic grass meal still needs attention.

  7. Identification of sources of lead in children in a primary zinc-lead smelter environment.

    PubMed Central

    Gulson, Brian L; Mizon, Karen J; Davis, Jeff D; Palmer, Jacqueline M; Vimpani, Graham

    2004-01-01

    We compared high-precision lead isotopic ratios in deciduous teeth and environmental samples to evaluate sources of lead in 10 children from six houses in a primary zinc-lead smelter community at North Lake Macquarie, New South Wales, Australia. Teeth were sectioned to allow identification of lead exposure in utero and in early childhood. Blood lead levels in the children ranged from 10 to 42 micro g/dL and remained elevated for a number of years. For most children, only a small contribution to tooth lead can be attributed to gasoline and paint sources. In one child with a blood lead concentration of 19.7 microg/dL, paint could account for about 45% of lead in her blood. Comparison of isotopic ratios of tooth lead levels with those from vacuum cleaner dust, dust-fall accumulation, surface wipes, ceiling (attic) dust, and an estimation of the smelter emissions indicates that from approximately 55 to 100% of lead could be derived from the smelter. For a blood sample from another child, > 90% of lead could be derived from the smelter. We found varying amounts of in utero-derived lead in the teeth. Despite the contaminated environment and high blood lead concentrations in the children, the levels of lead in the teeth are surprisingly low compared with those measured in children from other lead mining and smelting communities. PMID:14698931

  8. Geological and Geochemical Characteristics of Skarn Type Lead-Zinc Deposit in Baoshan Block, Yunnan Province

    NASA Astrophysics Data System (ADS)

    Yao, Xue; Wang, Peng

    2017-11-01

    Baoshan block is an important Pb-Zn-Fe-Cu polymetallic ore-concentration area which is located in southern of the Sanjiang metallogenic belt in western Yunnan. The article is studying about the geological and geochemical characteristics of the skarn type lead-zinc deposit in Baoshan block. The skarn-type lead-zinc deposit Baoshan block is characterized by skarn and skarn marble, and the orebodies are layered, or bedded along the interlayer fault, which are significantly controlled by structure. The research about Stable isotope S, H and O indicates that the ore-forming fluids are mainly derived from magmatic water, partly mixed with parts of metamorphic water and atmospheric precipitation. The initial Sr isotopic Sr87/Sr86 ratio suggests that the ore-forming materials derived from deep concealed magmatic rock, age of Rb-Sr mineralization is similar to that of Yanshanian granite. In conclusion, the Yanshanian tectonic-magmatic-fluid coupling mineralization of Yanshan formation is the main reason for the skarn-type lead-zinc deposit in the Baoshan block.

  9. Assimilation of zinc, cadmium, lead, copper, and iron by the spider Dysdera crocata, a predator of woodlice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hopkin, S.P.; Martin, M.H.

    1985-02-01

    In this paper, an experiment is described on the assimilation of zinc, cadmium, lead, copper and iron by Dysdera crocata collected from a site in central Bristol. The spiders were fed on woodlice from their own site, and on woodlice from a site contaminated by a smelting works which contained much higher levels of zinc, cadmium and lead than the spiders would have been used to in their normal diet.

  10. Preparation and adsorption characteristics for heavy metals of active silicon adsorbent from leaching residue of lead-zinc tailings.

    PubMed

    Lei, Chang; Yan, Bo; Chen, Tao; Xiao, Xian-Ming

    2018-05-19

    To comprehensively reuse the leaching residue obtained from lead-zinc tailings, an active silicon adsorbent (ASA) was prepared from leaching residue and studied as an adsorbent for copper(II), lead(II), zinc(II), and cadmium(II) in this paper. The ASA was prepared by roasting the leaching residue with either a Na 2 CO 3 /residue ratio of 0.6:1 at 700 °C for 1 h or a CaCO 3 /residue ratio of 0.8:1 at 800 °C for 1 h. Under these conditions, the available SiO 2 content of the ASA was more than 20%. The adsorption behaviors of the metal ions onto the ASA were investigated and the Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models were used to analyze the adsorption isotherm. The result showed that the maximum adsorption capacities of copper(II), lead(II), cadmium(II), and zinc(II) calculated by the Langmuir model were 3.40, 2.83, 0.66, and 0.62 mmol g -1 , respectively. The FT-IR spectra of the ASA and the mean free adsorption energies indicated that ion exchange was the mechanism of copper(II), lead(II), and cadmium(II) adsorption and that chemical reaction was the mechanism of zinc(II) adsorption. These results provide a method for reusing the leaching residue obtained from lead-zinc tailings and show that the ASA is an effective adsorbent for heavy metal pollution remediation.

  11. Environmental exposures to lead, mercury, and cadmium among South Korean teenagers (KNHANES 2010-2013): Body burden and risk factors.

    PubMed

    Kim, Nam-Soo; Ahn, Jaeouk; Lee, Byung-Kook; Park, Jungsun; Kim, Yangho

    2017-07-01

    Limited information is available on the association of age and sex with blood concentrations of heavy metals in teenagers. In addition, factors such as a shared family environment may have an association. We analyzed data from the Korean National Health and Nutrition Examination Survey (KNHANES, 2010-2013) to determine whether blood levels of heavy metals differ by risk factors such as age, sex, and shared family environment in a representative sample of teenagers. This study used data obtained in the KNHANES 2010-2013, which had a rolling sampling design that involved a complex, stratified, multistage, probability-cluster survey of a representative sample of the non-institutionalized civilian population in South Korea. Our cross-sectional analysis was restricted to teenagers and their parents who completed the health examination survey, and for whom blood measurements of cadmium, lead, and mercury were available. The final analytical sample consisted of 1585 teenagers, and 376 fathers and 399 mothers who provided measurements of blood heavy metal concentrations. Male teenagers had greater blood levels of lead and mercury, but sex had no association with blood cadmium level. There were age-related increases in blood cadmium, but blood lead decreased with age, and age had little association with blood mercury. The concentrations of cadmium and mercury declined from 2010 to 2013. The blood concentrations of lead, cadmium, and mercury in teenagers were positively associated with the levels in their parents after adjustment for covariates. Our results show that blood heavy metal concentrations differ by risk factors such as age, sex, and shared family environment in teenagers. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Mississippi Valley-Type Lead-Zinc Deposit Model

    USGS Publications Warehouse

    Leach, David L.; Taylor, Ryan D.

    2009-01-01

    Mississippi Valley-type (MVT) lead-zinc (Pb+Zn) deposits are found throughout the world, and these deposits are characteristically distributed over hundreds of square kilometers that define individual ore districts. The median size of individual MVT deposits is 7.0 million tonnes with grades of about 7.9 percent Pb+Zn metal. However, MVT deposits usually occur in extensive districts consisting of several to as many as 400 deposits. Nearly one-quarter of the world's sedimentary and volcanic rock-hosted Pb+Zn resources are found in these deposits, with by-product commodities including silver (Ag), copper (Cu), and indium (In) for some deposits. Environmentally, MVT deposits are less of a concern than other types of mineral deposits since the carbonate-host rocks mitigate many environmental concerns.

  13. Evaluation of novel reactive MgO activated slag binder for the immobilisation of lead and zinc.

    PubMed

    Jin, Fei; Al-Tabbaa, Abir

    2014-12-01

    Although Portland cement is the most widely used binder in the stabilisation/solidification (S/S) processes, slag-based binders have gained significant attention recently due to their economic and environmental merits. In the present study, a novel binder, reactive MgO activated slag, is compared with hydrated lime activated slag in the immobilisation of lead and zinc. A series of lead or zinc-doped pastes and mortars were prepared with metal to binder ratio from 0.25% to 1%. The hydration products and microstructure were studied by X-ray diffraction, thermogravimetric analysis and scanning electron microscopy. The major hydration products were calcium silicate hydrate and hydrotalcite-like phases. The unconfined compressive strength was measured up to 160 d. Findings show that lead had a slight influence on the strength of MgO-slag paste while zinc reduced the strength significantly as its concentration increased. Leachate results using the TCLP tests revealed that the immobilisation degree was dependent on the pH and reactive MgO activated slag showed an increased pH buffering capacity, and thus improved the immobilisation efficiency compared to lime activated slag. It was proposed that zinc was mainly immobilised within the structure of the hydrotalcite-like phases or in the form of calcium zincate, while lead was primarily precipitated as the hydroxide. It is concluded, therefore, that reactive MgO activated slag can serve as clinker-free alternative binder in the S/S process. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Recycling of Zinc- and Lead-Bearing Residues with Pyrolysis Gas

    NASA Astrophysics Data System (ADS)

    Pichler, C.; Antrekowitsch, J.

    2015-09-01

    Efforts in the metallurgical industry for an approximation to the zero waste concept has led to many different investigations. Together with the greenhouse effect, CO2 emissions have caused additional costs for different process steps in the industry. For this reason, alternative carbon carriers have been sought, and charcoal was found to be an ideal substitute, due to its CO2 neutrality. In order to use it in the metallurgical industry, an optimization of the charcoal production through a carbonization process must be carried out. Beside the charcoal, pyrolysis gas also occurs during the heating of wood or agricultural wastes under the exclusion of air. Because of combustible compounds in this gas, it is possible to use it as a reduction agent instead of fossil carbon carriers. Together with the idea of preventing landfilling of metallurgical by-products, an investigation was carried out to treat zinc- and lead-containing materials. For this issue a special process concept was designed and developed. The main aspect was to recycle the zinc- and lead-containing Waelz slag, which results from the processing of steel mill dusts, in a vertical retort. Two different sizes of facilities were constructed to perform the reaction system of the solid Waelz slag with the gaseous reduction agent of pyrolysis gas.

  15. Multivariate statistical assessment of heavy metal pollution sources of groundwater around a lead and zinc plant.

    PubMed

    Zamani, Abbas Ali; Yaftian, Mohammad Reza; Parizanganeh, Abdolhossein

    2012-12-17

    The contamination of groundwater by heavy metal ions around a lead and zinc plant has been studied. As a case study groundwater contamination in Bonab Industrial Estate (Zanjan-Iran) for iron, cobalt, nickel, copper, zinc, cadmium and lead content was investigated using differential pulse polarography (DPP). Although, cobalt, copper and zinc were found correspondingly in 47.8%, 100.0%, and 100.0% of the samples, they did not contain these metals above their maximum contaminant levels (MCLs). Cadmium was detected in 65.2% of the samples and 17.4% of them were polluted by this metal. All samples contained detectable levels of lead and iron with 8.7% and 13.0% of the samples higher than their MCLs. Nickel was also found in 78.3% of the samples, out of which 8.7% were polluted. In general, the results revealed the contamination of groundwater sources in the studied zone. The higher health risks are related to lead, nickel, and cadmium ions. Multivariate statistical techniques were applied for interpreting the experimental data and giving a description for the sources. The data analysis showed correlations and similarities between investigated heavy metals and helps to classify these ion groups. Cluster analysis identified five clusters among the studied heavy metals. Cluster 1 consisted of Pb, Cu, and cluster 3 included Cd, Fe; also each of the elements Zn, Co and Ni was located in groups with single member. The same results were obtained by factor analysis. Statistical investigations revealed that anthropogenic factors and notably lead and zinc plant and pedo-geochemical pollution sources are influencing water quality in the studied area.

  16. Multivariate statistical assessment of heavy metal pollution sources of groundwater around a lead and zinc plant

    PubMed Central

    2012-01-01

    The contamination of groundwater by heavy metal ions around a lead and zinc plant has been studied. As a case study groundwater contamination in Bonab Industrial Estate (Zanjan-Iran) for iron, cobalt, nickel, copper, zinc, cadmium and lead content was investigated using differential pulse polarography (DPP). Although, cobalt, copper and zinc were found correspondingly in 47.8%, 100.0%, and 100.0% of the samples, they did not contain these metals above their maximum contaminant levels (MCLs). Cadmium was detected in 65.2% of the samples and 17.4% of them were polluted by this metal. All samples contained detectable levels of lead and iron with 8.7% and 13.0% of the samples higher than their MCLs. Nickel was also found in 78.3% of the samples, out of which 8.7% were polluted. In general, the results revealed the contamination of groundwater sources in the studied zone. The higher health risks are related to lead, nickel, and cadmium ions. Multivariate statistical techniques were applied for interpreting the experimental data and giving a description for the sources. The data analysis showed correlations and similarities between investigated heavy metals and helps to classify these ion groups. Cluster analysis identified five clusters among the studied heavy metals. Cluster 1 consisted of Pb, Cu, and cluster 3 included Cd, Fe; also each of the elements Zn, Co and Ni was located in groups with single member. The same results were obtained by factor analysis. Statistical investigations revealed that anthropogenic factors and notably lead and zinc plant and pedo-geochemical pollution sources are influencing water quality in the studied area. PMID:23369182

  17. Arsenic, Cadmium, Chromium, Lead, Mercury and Selenium Concentrations in Pine Snakes (Pituophis melanoleucus) from the New Jersey Pine Barrens.

    PubMed

    Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Zappalorti, Robert; Pittfield, Taryn; DeVito, Emile

    2017-05-01

    Top trophic level predators are at risk from bioaccumulation of heavy metals from their prey. Using nondestructively collected tissues as a method of assessing metal concentrations in snakes is useful for populations that are threatened or declining. This paper reports concentrations of arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and selenium (Se) in tissues of Northern pine snakes (Pituophis melanoleucus) from the New Jersey Pine Barrens, a relatively pristine, undisturbed habitat. We also determined if skin is an appropriate indicator of internal concentrations and identified the factors (tissue, year of collection, length, sex) that might explain variations in metal concentrations. Because they can grow to 2-m long and live for 25 years, we suggest that these snakes might accumulate heavy metals. Multiple regression models were significant, explaining 16% (lead) to 61% (mercury) of variation by tissue type. For mercury and chromium, size also was significant. The highest concentrations were in liver and kidney for all metals, except chromium and lead. Mercury concentrations in tissues were within the range reported for other snakes and were below effects concentrations in reptiles. The concentrations in skin were correlated with all internal tissues for mercury and for all internal tissues except heart for cadmium. These data show that shed skin can be used as an indicator of metals in pine snakes and that, at present, concentrations of heavy metals in this population are within the range of those found in other snake species from uncontaminated sites.

  18. Detoxification of mercury, cadmium, and lead in Klebsiella aerogenes NCTC 418 growing in continuous culture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aiking, H.; Govers, H.; van 'T Riet, J.

    1985-11-01

    Klebsiella aerogenes NCTC 418 growing in the presence of cadmium under glucose-, sulfate-, or phosphate-limited conditions in continuous culture exhibited sulfide formation and P/sub i/ accumulation as the only demonstrable detoxification mechanisms. In the presence of mercury under similar conditions only HgS formation could be confirmed, by an increased sensitivity to mercury under sulfate-limited conditions, among others. The fact that the cells were most sensitive to cadmium under conditions of phosphate limitation and most sensitive to mercury under conditions of sulfate limitation led to the hypothesis that these inorganic detoxification mechanisms generally depended on a kind of facilitated precipitation. Themore » process was coined thus because heavy metals were probably accumulated and precipitated near the cell perimeter due to the relatively high local concentrations of sulfide and phosphate there. Depending on the growth-limiting nutrient, mercury proved to be 25-fold (phosphate limitation), 75-fold (glycerol limitation), or 150-fold (sulfate limitation) more toxic than cadmium to this organism. In the presence of lead, PbS formation was suggested. since no other detoxification mechanisms were detected, for example, rendering heavy metal ions innocuous as metallo-organic compounds, it was concluded that formation of heavy metal precipitates is crucially important to this organism. In addition, it was observed that several components of a defined mineral medium were able to reduce mercuric ions to elemental mercury. This abiotic mercury volatilization was studied in detail, and its general and environmental implications are discussed.« less

  19. Lead, mercury, and arsenic in US- and Indian-manufactured Ayurvedic medicines sold via the Internet.

    PubMed

    Saper, Robert B; Phillips, Russell S; Sehgal, Anusha; Khouri, Nadia; Davis, Roger B; Paquin, Janet; Thuppil, Venkatesh; Kales, Stefanos N

    2008-08-27

    Lead, mercury, and arsenic have been detected in a substantial proportion of Indian-manufactured traditional Ayurvedic medicines. Metals may be present due to the practice of rasa shastra (combining herbs with metals, minerals, and gems). Whether toxic metals are present in both US- and Indian-manufactured Ayurvedic medicines is unknown. To determine the prevalence of Ayurvedic medicines available via the Internet containing detectable lead, mercury, or arsenic and to compare the prevalence of toxic metals in US- vs Indian-manufactured medicines and between rasa shastra and non-rasa shastra medicines. A search using 5 Internet search engines and the search terms Ayurveda and Ayurvedic medicine identified 25 Web sites offering traditional Ayurvedic herbs, formulas, or ingredients commonly used in Ayurveda, indicated for oral use, and available for sale. From 673 identified products, 230 Ayurvedic medicines were randomly selected for purchase in August-October 2005. Country of manufacturer/Web site supplier, rasa shastra status, and claims of Good Manufacturing Practices were recorded. Metal concentrations were measured using x-ray fluorescence spectroscopy. Prevalence of medicines with detectable toxic metals in the entire sample and stratified by country of manufacture and rasa shastra status. One hundred ninety-three of the 230 requested medicines were received and analyzed. The prevalence of metal-containing products was 20.7% (95% confidence interval [CI], 15.2%-27.1%). The prevalence of metals in US-manufactured products was 21.7% (95% CI, 14.6%-30.4%) compared with 19.5% (95% CI, 11.3%-30.1%) in Indian products (P = .86). Rasa shastra compared with non-rasa shastra medicines had a greater prevalence of metals (40.6% vs 17.1%; P = .007) and higher median concentrations of lead (11.5 microg/g vs 7.0 microg/g; P = .03) and mercury (20,800 microg/g vs 34.5 microg/g; P = .04). Among the metal-containing products, 95% were sold by US Web sites and 75% claimed Good

  20. [Evaluation of cadmium, mercury and lead intake with reproduced weekly food rations].

    PubMed

    Marzec, Z; Buliński, R

    1991-01-01

    In Lublin, Olsztyn, Poznań, Warszawa and Wrocław, weekly food rations characteristic of families other than those of manual workers, with medium incomes, were reproduced. Food rations comprised ca. 90 food products whose average weekly intakes were established consistently with the results of questionnaires of the Chief Census Bureau. Namely, from these results we calculated and prepared the average weekly food rations (from 11 470 g to 14 732 g), in which cadmium, mercury and lead were assayed by the ASA method. These average food rations afforded weekly intakes of 105-147 micrograms Cd, 441-931 micrograms Pb and 50.5-119.0 micrograms Hg. According to these results, the average food rations from the above-mentioned cities are moderately contaminated with the heavy metals tested, because in no case 50% of the provisional tolerable weekly intake (PTWI) were exceeded. The present results are lower than those obtained in the same year for families of manual workers; this is probably due to the fact that in the families of manual workers, as compared with other families, the weight of meals is usually higher. It is noteworthy that in the cities with greater numbers of industrial plants the contents of the metals tested, particularly of mercury and lead, in food are higher.

  1. Lead, Mercury, and Arsenic in US- and Indian-Manufactured Ayurvedic Medicines Sold via the Internet

    EPA Science Inventory

    Lead, mercury, and arsenic have been detected in a subsantial portion of Indian-manufactured traditional Ayurvedic medicines. Metals may be present due to the parctice of rasa shastra (combining herbs with metals, minerals and gems). Whether toxic metals are present in both US-...

  2. Influence of lead ions on the macromorphology of electrodeposited zinc

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsuda, Tetsuaki; Tobias, Charles W.

    1981-09-01

    The morphology of zinc as it is electrodeposited from acid solutions demonstrates a remarkable imprint of electrolyte flow conditions. The development of macromorphology of zinc deposits has been investigated under galvanostatic conditions on a rotating plantinum disk electrode by use of photomacrography, scanning electron microscopy, electron probe microanalysis and Auger microprobe analysis. Logarithmic spiral markings, which reflect the hydrodynamic flow on a rotating disk, appear in a certain region of current density well below the limiting current density. Morphological observations revealed the major influence of trace lead ions on the amplifications of surface roughness through coalescence and preferred growth ofmore » initial protrusions. Results obtained from ultra-pure electrolyte suggest preferred crystal growth towards well-mixed orientation in the concentration field caused by slight differences in crystallization overpotential. A qualitative model involving a coupling mechanism between the evolving surface roughness and instability phenomena in the boundary layer is advanced to explain the formation of spiral patterns.« less

  3. Biosorption of lead, cadmium, and zinc by Citrobacter strain MCM B-181: Characterization studies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Puranik, P.R.; Paknikar, K.M.

    1999-03-01

    The biosorption process for removal of lead, cadmium, and zinc by Citrobacter strain MCM B-181, a laboratory isolate, was characterized. Effects of environmental factors and growth conditions on metal uptake capacity were studied. Pretreatment of biomass with chemical agents increased cadmium sorption efficiency; however, there was no significant enhancement in lead and zinc sorption capacity. Metal sorption by Citrobacter strain MCM B-181 was found to be influenced by the pH of the solution, initial metal concentration, biomass concentration, and type of growth medium. The metal sorption process was not affected by the age of the culture or change in temperature.more » Equilibrium metal sorption was found to fit the Langmuir adsorption model. Kinetic studies showed that metal uptake by Citrobacter strain MCm B-181 was a fast process, requiring < 20 min to achieve > 90% adsorption efficiency. The presence of cations reduced lead, zinc, and cadmium sorption to the extent of 11.8%, 84.3%, and 33.4%, respectively. When biomass was exposed to multimetal solutions, metals were adsorbed in the order Co{sup 2+} < Ni{sup 2+} < Cd{sup 2+} < Cu{sup 2+}, Zn{sup 2+} < Pb{sup 2+}. A new mathematical model used for batch kinetic studies was found to be highly useful in prediction of experimentally obtained metal concentration profiles as a function of time.« less

  4. Mercury, lead, and cadmium in blue crabs, Callinectes sapidus, from the Atlantic coast of Florida, USA: a multipredator approach.

    PubMed

    Adams, Douglas H; Engel, Marc E

    2014-04-01

    Blue crabs, Callinectes sapidus, from the Atlantic coast of Florida were analyzed for total mercury, methylmercury, lead, and cadmium. Paired samples of two tissue types were analyzed for each crab, (1) muscle tissue (cheliped and body muscles) and (2) whole-body tissue (all organs, muscle tissue and connective tissue), for evaluation of the concentration of metals available to human consumers as well as estuarine predators. There were clear patterns of tissue-specific partitioning for each metal. Total mercury was significantly greater in muscle tissue (mean=0.078 µg/g) than in whole-body tissue (mean=0.055 µg/g). Conversely, whole-body concentrations of lead and cadmium (means=0.131 and 0.079 µg/g, respectively) were significantly greater than concentrations in muscle (means=0.02 and 0.029 µg/g, respectively). There were no significant correlations between any metal contaminant and crab size. Cadmium levels were significantly greater in the muscle tissue of females, but, no other sex-related differences were seen for other metals or tissue types. Methylmercury composed 93-100% of the total mercury in tissues. Compared to previous blue crab studies from different regions of the United States, mean concentrations of mercury, lead, and cadmium were relatively low, although isolated groups or individual blue crabs accumulated high metal concentrations. © 2013 Published by Elsevier Inc.

  5. Re-evaluation of blood mercury, lead and cadmium concentrations in the Inuit population of Nunavik (Québec): a cross-sectional study

    PubMed Central

    Fontaine, Julie; Dewailly, Éric; Benedetti, Jean-Louis; Pereg, Daria; Ayotte, Pierre; Déry, Serge

    2008-01-01

    Background Arctic populations are exposed to mercury, lead and cadmium through their traditional diet. Studies have however shown that cadmium exposure is most often attributable to tobacco smoking. The aim of this study is to examine the trends in mercury, lead and cadmium exposure between 1992 and 2004 in the Inuit population of Nunavik (Northern Québec, Canada) using the data obtained from two broad scale health surveys, and to identify sources of exposure in 2004. Methods In 2004, 917 adults aged between 18 and 74 were recruited in the 14 communities of Nunavik to participate to a broad scale health survey. Blood samples were collected and analysed for metals by inductively coupled plasma mass spectrometry, and dietary and life-style characteristics were documented by questionnaires. Results were compared with data obtained in 1992, where 492 people were recruited for a similar survey in the same population. Results Mean blood concentration of mercury was 51.2 nmol/L, which represent a 32% decrease (p < 0.001) between 1992 and 2004. Mercury blood concentrations were mainly explained by age (partial r2 = 0.20; p < 0.0001), and the most important source of exposure to mercury was marine mammal meat consumption (partial r2 = 0.04; p < 0.0001). In 2004, mean blood concentration of lead was 0.19 μmol/L and showed a 55% decrease since 1992. No strong associations were observed with any dietary source, and lead concentrations were mainly explained by age (partial r2 = 0.20.; p < 0.001). Blood cadmium concentrations showed a 22% decrease (p < 0.001) between 1992 and 2004. Once stratified according to tobacco use, means varied between 5.3 nmol/L in never-smokers and 40.4 nmol/L in smokers. Blood cadmium concentrations were mainly associated with tobacco smoking (partial r2 = 0.56; p < 0.0001), while consumption of caribou liver and kidney remain a minor source of cadmium exposure among never-smokers. Conclusion Important decreases in mercury, lead and cadmium exposure

  6. Use of natural clinoptilolite for the removal of lead, copper and zinc in fixed bed column.

    PubMed

    Stylianou, Marinos A; Hadjiconstantinou, Michalis P; Inglezakis, Vasilis J; Moustakas, Konstantinos G; Loizidou, Maria D

    2007-05-08

    This work deals with the removal of lead, copper and zinc from aqueous solutions by using natural zeolite (clinoptilolite). Fixed bed experiments were performed, using three different volumetric flow rates of 5, 7 and 10bed volume/h, under a total normality of 0.01N, at initial pH of 4 and ambient temperature (25 degrees C). The removal efficiency increased when decreasing the flow rate and the following selectivity series was found: Pb(2+)>Zn(2+)> or =Cu(2+). Conductivity measurements showed that lead removal follows mainly ion exchange mechanism, while copper and zinc removal follows ion exchange and sorption mechanism as well.

  7. Environmental Mercury and Its Toxic Effects

    PubMed Central

    Rice, Kevin M.; Walker, Ernest M.; Wu, Miaozong; Gillette, Chris

    2014-01-01

    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. PMID:24744824

  8. Lead, Mercury, and Arsenic in US- and Indian-Manufactured Ayurvedic Medicines Sold via the Internet

    PubMed Central

    Saper, Robert B.; Phillips, Russell S.; Sehgal, Anusha; Khouri, Nadia; Davis, Roger B.; Paquin, Janet; Thuppil, Venkatesh; Kales, Stefanos N.

    2009-01-01

    Context Lead, mercury, and arsenic have been detected in a substantial proportion of Indian-manufactured traditional Ayurvedic medicines. Metals may be present due to the practice of rasa shastra (combining herbs with metals, minerals, and gems). Whether toxic metals are present in both US- and Indian-manufactured Ayurvedic medicines is unknown. Objectives To determine the prevalence of Ayurvedic medicines available via the Internet containing detectable lead, mercury, or arsenic and to compare the prevalence of toxic metals in US- vs Indian-manufactured medicines and between rasa shastra and non–rasa shastra medicines. Design A search using 5 Internet search engines and the search terms Ayurveda and Ayurvedic medicine identified 25 Web sites offering traditional Ayurvedic herbs, formulas, or ingredients commonly used in Ayurveda, indicated for oral use, and available for sale. From 673 identified products, 230 Ayurvedic medicines were randomly selected for purchase in August–October 2005. Country of manufacturer/Web site supplier, rasa shastra status, and claims of Good Manufacturing Practices were recorded. Metal concentrations were measured using x-ray fluorescence spectroscopy. Main Outcome Measures Prevalence of medicines with detectable toxic metals in the entire sample and stratified by country of manufacture and rasa shastra status. Results One hundred ninety-three of the 230 requested medicines were received and analyzed. The prevalence of metal-containing products was 20.7% (95% confidence interval [CI], 15.2%–27.1%). The prevalence of metals in US-manufactured products was 21.7% (95% CI, 14.6%–30.4%) compared with 19.5% (95% CI, 11.3%–30.1%) in Indian products (P=.86). Rasa shastra compared with non–rasa shastra medicines had a greater prevalence of metals (40.6% vs 17.1%; P=.007) and higher median concentrations of lead (11.5 μg/g vs 7.0 μg/g; P=.03) and mercury (20 800 μg/g vs 34.5 μg/g; P=.04). Among the metal-containing products, 95

  9. The contents and distributions of cadmium, mercury, and lead in Usnea antarctica lichens from Solorina Valley, James Ross Island (Antarctica).

    PubMed

    Zvěřina, Ondřej; Coufalík, Pavel; Barták, Miloš; Petrov, Michal; Komárek, Josef

    2017-12-11

    Lichens are efficient and cost-effective biomonitors of the environment. Their geographic distribution together with their slow growth rate enable investigation of the deposition patterns of various elements and substances. In this research, levels of cadmium, lead, and mercury in Usnea antarctica lichens in the area of James Ross Island, Antarctica, were investigated. The lichens were microwave-digested, and the metals were determined by means of atomic absorption spectrometry with graphite furnace and a direct mercury analyzer. Median total contents of Cd, Hg, and Pb were 0.04, 0.47, and 1.6 mg/kg in whole lichens, respectively. The bottom-up distributions of these metals in the fruticose lichen thalli were investigated, and it was revealed that the accumulation patterns for mercury and lead were opposite to that for cadmium. The probable reason for this phenomenon may lie in the inner structure of thalli. The total contents of metals were comparable with those published for other unpolluted areas of maritime Antarctica. However, this finding was not expected for mercury, since the sampling locality was close to an area with some of the highest mercury contents published for Antarctic lichens. In short, lichens proved their usability as biological monitors, even in harsh conditions. However, the findings emphasize the need to take into account the distributions of elements both in the environment and in the lichen itself.

  10. Removal of metals from lead-zinc mine tailings using bioleaching and followed by sulfide precipitation.

    PubMed

    Ye, Maoyou; Li, Guojian; Yan, Pingfang; Ren, Jie; Zheng, Li; Han, Dajian; Sun, Shuiyu; Huang, Shaosong; Zhong, Yujian

    2017-10-01

    Mine tailings often contain significant amounts of metals and sulfide, many traditional operations used to minerals was not as good as those currently available. This study investigated metals removal from lead-zinc mine tailings using bioleaching and followed by sulfide precipitation. Metals were dissolved from the tailings by the bacteria in a bioleaching reactor. During a 10% pulp density bioleaching experiment, approximately 0.82% Pb, 97.38% Zn, and 71.37% Fe were extracted after 50 days. With the pulp density of 10% and 20%, the dissolution of metals followed shrinking core kinetic model. Metals (Pb, Zn, and Fe) present in the pregnant bioleaching leachate. Metals were next precipitated as a sulfide phase using sodium sulfide (Na 2 S). Metal precipitations were selectively and quantitatively produced from the bioleaching leachate by adding Na 2 S. More than 99% of the zinc and 75% of the iron was precipitated using 25 g/L Na 2 S in the bioleaching leachate. The results in the study were to provide useful information for recovering or removing metals from lead-zinc mine tailings. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Biomonitoring the environmental impact of atmospheric emissions from the Avonmouth zinc smelter, United Kingdom.

    PubMed

    Sims, Ian; Crane, Mark; Johnson, Ian; Credland, Peter

    2009-10-01

    This paper examines the impact of an industrial point-source atmospheric emission on the feeding of early life stages of a terrestrial invertebrate. Larvae of a bagworm moth, Luffia ferchaultella [Stephens], were fed terrestrial epiphytic algae (Desmococcus viridis [Menegh]) collected from five sites located along a 16 km transect around the Avonmouth zinc smelter. After 10 days of exposure symptoms of lethal and sublethal toxicity (mortality and paralysis) were observed. Reductions in the amount of faecal material (frass) produced were also identified, and these correlated with distance downwind of the smelter. The elevated concentrations of lead, mercury, arsenic, antimony, copper, cadmium, lead and nickel present in the algae could account for these symptoms of toxicity. Similar symptoms were observed when larvae were fed algae spiked with inorganic mercury. These results are consistent with other studies of soil toxicity conducted around the Avonmouth smelter. However, the current study suggests that the impacted area exceeds this 16 km transect and demonstrates the value of bagmoth larvae as sensitive biomonitors of metallic atmospheric pollutants above the rhizosphere.

  12. Mercury, cadmium, lead, and selenium in three waterbird species nesting in Galveston Bay, Texas, USA

    USGS Publications Warehouse

    King, K.A.; Cromartie, E.

    1986-01-01

    Heavy metal and selenium concentrations were determined in Olivaceous Cormorants (Phalacrocorax olivaceus ), Laughing gulls (Larus atricilla ), and Black Skimmers (Rynchops niger ) nesting in Galveston Bay, Texas, during 1980-81. Lead was detected at low levels in a small proportion of the liver samples. Mercury was present in all livers sampled, the highest levels being found in cormorants (7.8 ppm) and skimmers (16 ppm). Concentrations were considerably lower than those reported in birds from mercury-contaminated lakes in northern United States and Canada. Cadmium and selenium were detected in 93 and 95% of the kidneys. Cadmium was highest in gulls and skimmers with a maximum value of 16 ppm. Selenium levels were similar among species except for higher concentrations in gulls collected in 1981.

  13. VO2+ ions in zinc lead borate glasses studied by EPR and optical absorption techniques.

    PubMed

    Prakash, P Giri; Rao, J Lakshmana

    2005-09-01

    Electron paramagnetic resonance (EPR) and optical absorption spectra of vanadyl ions in zinc lead borate (ZnO-PbO-B2O3) glass system have been studied. EPR spectra of all the glass samples exhibit resonance signals characteristic of VO2+ ions. The values of spin-Hamiltonian parameters indicate that the VO2+ ions in zinc lead borate glasses were present in octahedral sites with tetragonal compression and belong to C4V symmetry. The spin-Hamiltonian parameters g and A are found to be independent of V2O5 content and temperature but changing with ZnO content. The decrease in Deltag( parallel)/Deltag( perpendicular) value with increase in ZnO content indicates that the symmetry around VO2+ ions is more octahedral. The decrease in intensity of EPR signal above 10 mol% of V2O5 is attributed to a fall in the ratio of the number of V4+ ions (N4) to the number of V5+ ions (N5). The number of spins (N) participating in resonance was calculated as a function of temperature for VO2+ doped zinc lead borate glass sample and the activation energy was calculated. From the EPR data, the paramagnetic susceptibility was calculated at various temperatures and the Curie constant was evaluated from the 1/chi-T graph. The optical absorption spectra show single absorption band due to VO2+ ions in tetragonally distorted octahedral sites.

  14. New insight into atmospheric mercury emissions from zinc smelters using mass flow analysis.

    PubMed

    Wu, Qingru; Wang, Shuxiao; Hui, Mulin; Wang, Fengyang; Zhang, Lei; Duan, Lei; Luo, Yao

    2015-03-17

    The mercury (Hg) flow paths from three zinc (Zn) smelters indicated that a large quantity of Hg, approximately 38.0-57.0% of the total Hg input, was stored as acid slag in the landfill sites. Approximately 15.0-27.1% of the Hg input was emitted into water or stored as open-dumped slags, and 3.3-14.5% of the Hg input ended in sulfuric acid. Atmospheric Hg emissions, accounting for 1.4-9.6% of the total Hg input, were from both the Zn production and waste disposal processes. Atmospheric Hg emissions from the waste disposal processes accounted for 40.6, 89.6, and 94.6% of the total atmospheric Hg emissions of the three studied smelters, respectively. The Zn production process mainly contributed to oxidized Hg (Hg2+) emissions, whereas the waste disposal process generated mostly elemental Hg (Hg0) emissions. When the emissions from these two processes are considered together, the emission proportion of the Hg2+ mass was 51, 46, and 29% in smelters A, B, and C, respectively. These results indicated that approximately 10.8±5.8 t of atmospheric Hg emissions from the waste disposal process were ignored in recent inventories. Therefore, the total atmospheric Hg emissions from the Zn industry of China should be approximately 50 t.

  15. Pollution by Arsenic, Mercury and other Heavy Metals in Sunchulli mining district of Apolobamba (Bolivia)

    NASA Astrophysics Data System (ADS)

    Terán Mita, Tania; Faz Cano, Angel; Muñoz, Maria Angeles; Millán Gómez, Rocio; Chincheros Paniagua, Jaime

    2010-05-01

    In Bolivia, metal mining activities since historical times have been one of the most important sources of environmental pollution. This is the case of the National Area of Apolobamba Integrated Management (ANMIN of Apolobamba) in La Paz, Bolivia, where intense gold mining activities have been carried out from former times to the present, with very little gold extraction and very primitive mineral processing technology; in fact, mercury is still being used in the amalgam processes of the gold concentration, which is burned outdoors to recover the gold. Sunchullí is a representative mining district in ANMIN of Apolobamba where mining activity is mainly gold extraction and its water effluents go to the Amazonian basin; in this mining district the productivity of extracted mineral is very low but the processes can result in heavy-metal contamination of the air, water, soils and plants. Due to its high toxicity, the contamination by arsenic and mercury create the most critical environmental problems. In addition, some other heavy metals may also be present such as lead, copper, zinc and cadmium. These heavy metals could be incorporated in the trophic chain, through the flora and the fauna, in their bio-available and soluble forms. Inhabitants of this area consume foodcrops, fish from lakes and rivers and use the waters for the livestock, domestic use, and irrigation. The aim of this work was to evaluate the heavy metals pollution by gold mining activities in Sunchullí area. In Sunchullí two representative zones were distinguished and sampled. Zone near the mining operation site was considered as affected by mineral extraction processes, while far away zones represented the non affected ones by the mining operation. In each zone, 3 plots were established; in each plot, 3 soil sampling points were selected in a random manner and analysed separately. In each sampling point, two samples were taken, one at the surface, from 0-5 cm depth (topsoil), and the other between 5

  16. Zinc Chloride and Lead Acetate-Induced Passive Avoidance Memory Retention Deficits Reversed by Nicotine and Bucladesine in Mice.

    PubMed

    Tabrizian, Kaveh; Yazdani, Abdolmajid; Baheri, Behnam; Payandemehr, Borna; Sanati, Mehdi; Hashemzaei, Mahmoud; Miri, Abdolhossein; Zandkarimi, Majid; Belaran, Maryam; Fanoudi, Sahar; Sharifzadeh, Mohammad

    2016-01-01

    It is very important to investigate the neurotoxic effects of metals on learning and memory processes. In this study, we tried to investigate the effects and time course properties of oral administration of zinc chloride (25, 50, and 75 mg/kg, for 2 weeks), lead acetate (250, 750, 1,500, and 2,500 ppm for 4, 6 and 8 weeks), and their possible mechanisms on a model of memory function. For this matter, we examined the intra-peritoneal injections of nicotine (0.25, 0.5, 1, and 1.5 mg/kg) and bucladesine (50, 100, 300, and 600 nM/mouse) for 4 days alone and in combination with mentioned metals in the step-through passive avoidance task. Control animals received saline, drinking water, saline, and DMSO (dimethyl sulfoxide)/deionized water (1:9), respectively. At the end of each part of studies, animals were trained for 1 day in step-through task. The avoidance memory retention alterations were evaluated 24 and 48 h later in singular and combinational studies. Zinc chloride (75 mg/kg) oral gavage for 2 weeks decreased latency times compared to control animals. Also, lead acetate (750 ppm oral administrations for 8 weeks) caused significant lead blood levels and induced avoidance memory retention impairments. Four-days intra-peritoneal injection of nicotine (1 mg/kg) increased latency time compared to control animals. Finally, findings of this research showed that treatment with intra-peritoneal injections of nicotine (1 mg/kg) and/or bucladesine (600 nM/mouse) reversed zinc chloride- and lead acetate-induced avoidance memory retention impairments. Taken together, these results showed the probable role of cholinergic system and protein kinase A pathways in zinc chloride- and lead acetate-induced avoidance memory alterations.

  17. Simultaneous determination of thorium, niobium, lead, and zinc by photon-induced x-ray fluorescence of lateritic material

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LaBrecque, J.J.; Adames, D.; Parker, W.C.

    1981-01-01

    A rapid method is presented for the simultaneous determinations of thorium, niobium, lead, and zinc in lateritic material from Cerro Impacto, Estado Bolivar, Venezuela. This technique uses a PDP - 11/05 processor - based photon induced x-ray fluorescence system. The total variations of approximately 5% for concentrations of approximately 1 and 10% for concentrations of approximately 0.1% were obtained with only 500 s of fluorescent time. The values obtained by this method were in agreement with values measured by conventional flame atomic absorption spectroscopy for lead and zinc. The values for thorium measured were in agreement with the reported valuesmore » for the reference materials supplied by NBL.« less

  18. Prenatal lead, cadmium and mercury exposure and associations with motor skills at age 7 years in a UK observational birth cohort.

    PubMed

    Taylor, Caroline M; Emond, Alan M; Lingam, Raghu; Golding, Jean

    2018-08-01

    Lead and mercury are freely transferred across the placenta, while cadmium tends to accumulate in the placenta. Each contributes to adverse neurological outcomes for the child. Although prenatal heavy metal exposure has been linked with an array of neurodevelopmental outcomes in childhood, its association with the development of motor skills in children has not been robustly studied. The aim of the present study was to investigate the association between prenatal exposure to lead, cadmium and mercury, measured as maternal blood concentrations during pregnancy, and motor skills, measured as subtests of the Movement Assessment Battery for Children (Movement ABC) at age 7 years in a large sample of mother-child pairs enrolled in a UK observational birth cohort study (Avon Longitudinal Study of Parents and Children, ALSPAC). Whole blood samples from pregnant women enrolled in ALSPAC were analysed for lead, cadmium and mercury. In a complete case analysis (n = 1558), associations between prenatal blood concentrations and child motor skills assessed by Movement ABC subtests of manual dexterity, ball skills and balance at 7 years were examined in adjusted regression models. Associations with probable developmental coordination disorder (DCD) were also investigated. The mean prenatal blood levels were: lead 3.66 ± 1.55 μg/dl; cadmium 0.45 ± 0.54 μg/l; mercury 2.23 ± 1.14 μg/l. There was no evidence for any adverse associations of prenatal lead, cadmium or mercury exposure with motor skills measured at age 7 years with Movement ABC subtests in adjusted regression models. Further, there were no associations with probable DCD. There was no evidence to support a role of prenatal exposure to heavy metals at these levels on motor skills in the child at age 7 years measured using the Movement ABC. Early identification of symptoms of motor skills impairment is important, however, to enable investigation, assessment and treatment. Copyright

  19. Interactions of dietary calcium with toxic levels of lead and zinc in pigs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hsu, F.A.; Krook, L.; Pond, W.G.

    1975-01-01

    Twenty-four weanling Yorkshire pigs were used in a 2 x 2 x 2 factorial arrangement of treatments to determine their response to high levels of dietary lead (Pb) (1000 ppm) and zinc (Zn) (4000 ppm) (as lead acetate and zinc oxide), to investigate the influence of high dietary calcium (Ca) (1.1%) on the biochemical and morphological manifestations of Pb and Zn toxicity, and to determine the effect of excess Zn on Pb toxicity. Clinical signs of Pb toxicity included behavioral changes, lameness, and anorexia. Pb content of blood, soft tissues, and bone was increased markedly by 1000 ppm Pb inmore » the diet during the 13-week experiment. Zn and Pb fed together, as compared with Pb alone, tended to increase Pb levels in blood, soft tissues, and bone and to enhance the toxic effects of Pb as shown by reduced weight gains, severe clinical signs, and pathological changes. High Ca reduced blood and bone Zn and Pb concentrations. The results indicate that high dietary Ca has a protective effect against the adverse effects of diet Pb and Zn, and that Zn aggravates Pb toxicity in growing pigs.« less

  20. Biomonitoring of Lead, Cadmium, Total Mercury, and Methylmercury Levels in Maternal Blood and in Umbilical Cord Blood at Birth in South Korea

    PubMed Central

    Kim, Yu-Mi; Chung, Jin-Young; An, Hyun Sook; Park, Sung Yong; Kim, Byoung-Gwon; Bae, Jong Woon; Han, Myoungseok; Cho, Yeon Jean; Hong, Young-Seoub

    2015-01-01

    With rising concerns of heavy metal exposure in pregnancy and early childhood, this study was conducted to assess the relationship between the lead, cadmium, mercury, and methylmercury blood levels in pregnancy and neonatal period. The study population included 104 mothers and their children pairs who completed both baseline maternal blood sampling at the second trimester and umbilical cord blood sampling at birth. The geometric mean maternal blood levels of lead, cadmium, total mercury, and methylmercury at the second trimester were 1.02 ± 1.39 µg/dL, 0.61 ± 1.51 µg/L, 2.97 ± 1.45 µg/L, and 2.39 ± 1.45 µg/L, respectively, and in the newborns, these levels at birth were 0.71 ± 1.42 µg/dL, 0.01 ± 5.31 µg/L, 4.44 ± 1.49 µg/L, and 3.67 ± 1.51 µg/L, respectively. The mean ratios of lead, cadmium, total mercury, and methylmercury levels in the newborns to those in the mothers were 0.72, 0.04, 1.76, and 1.81, respectively. The levels of most heavy metals in pregnant women and infants were higher in this study than in studies from industrialized western countries. The placenta appears to protect fetuses from cadmium; however, total mercury and methylmercury were able to cross the placenta and accumulate in fetuses. PMID:26516876

  1. [Improvement in zinc nutrition due to zinc transporter-targeting strategy].

    PubMed

    Kambe, Taiho

    2016-07-01

    Adequate intake of zinc from the daily diet is indispensable to maintain health. However, the dietary zinc content often fails to fulfill the recommended daily intake, leading to zinc deficiency and also increases the risk of developing chronic diseases, particularly in elderly individuals. Therefore, increased attention is required to overcome zinc deficiency and it is important to improve zinc nutrition in daily life. In the small intestine, the zinc transporter, ZIP4, functions as a component that is essential for zinc absorption. In this manuscript, we present a brief overview regarding zinc deficiency. Moreover, we review a novel strategy, called "ZIP4-targeting", which has the potential to enable efficient zinc absorption from the diet. ZIP4-targeting strategy is possibly a major step in preventing zinc deficiency and improving human health.

  2. Alternative drugs go global: possible lead and/ or mercury intoxication from imported natural health products and a need for scientifically evaluated poisoning monitoring from environmental exposures.

    PubMed

    Budnik, Lygia Therese; Baur, Xaver; Harth, Volker; Hahn, Axel

    2016-01-01

    With increases in globalization, cultural remedies from Chinese, Ayurvedic, Arab and other traditions have become more available to international consumers, offering unfamiliar "Natural Health Products" (NHP), used as alternative medicine or supplementary medicine. Contamination with toxic ingredients including lead, mercury, arsenic, and other toxic elements has been documented in several of these products from various parts of the globe, particularly from some parts of Asia and the Orient. We have been following this development in the last 6 years and have analyzed n  = 20 such products (60 analyses) from patients with intoxication symptoms in a pilot study, showing alarming high concentrations of mercury and/or lead (the first one in "therapeutic" doses). 82 % of the studied NHP contained lead concentrations above the EU limit for dietary supplements. 62 % of the samples exceeded the limit values for mercury. Elevated blood lead and mercury levels in patients along with clinical intoxication symptoms corroborate the causal assumption of intoxication (s). We present one detailed clinical case report of severe lead and mercury intoxications and give an overview about blood concentration related symptoms and signs of n  = 41 case reports of mercury intoxications of the German monitoring BfR-DocCenter. For NHP there is evidence on a distinct toxicological risk with alarming low awareness for a possible intoxication which prevents potentially life-saving diagnostic steps in affected cases. In many cases patients do not communicate the events to their physicians or the local health authority so that case reports (e.g. the BfR-DocCentre) are missing. Thus, there is an urgent need to raise awareness and to initiate more suitable monitory systems (e.g. National Monitoring of Poisonings) and control practice protecting the public.

  3. Loading estimates of lead, copper, cadmium, and zinc in urban runoff from specific sources.

    PubMed

    Davis, A P; Shokouhian, M; Ni, S

    2001-08-01

    Urban stormwater runoff is being recognized as a substantial source of pollutants to receiving waters. A number of investigators have found significant levels of metals in runoff from urban areas, especially in highway runoff. As an initiatory study, this work estimates lead, copper, cadmium, and zinc loadings from various sources in a developed area utilizing information available in the literature, in conjunction with controlled experimental and sampling investigations. Specific sources examined include building siding and roofs; automobile brakes, tires, and oil leakage; and wet and dry atmospheric deposition. Important sources identified are building siding for all four metals, vehicle brake emissions for copper and tire wear for zinc. Atmospheric deposition is an important source for cadmium, copper, and lead. Loadings and source distributions depend on building and automobile density assumptions and the type of materials present in the area examined. Identified important sources are targeted for future comprehensive mechanistic studies. Improved information on the metal release and distributions from the specific sources, along with detailed characterization of watershed areas will allow refinements in the predictions.

  4. [Effects of Different Modifier Concentrations on Lead-Zinc Tolerance, Subcellular Distribution and Chemical Forms for Four Kinds of Woody Plants].

    PubMed

    Chen, Yong-hua; Zhang, Fu-yun; Wu, Xiao-fu; Liang, Xi; Yuan, Si-wen

    2015-10-01

    Four kinds of lead-zinc tolerant woody plants: Nerium oleander, Koelreuteria paniculata, Paulownia and Boehmeria were used as materials to estimate their enrichment and transferable capacity of lead (Pb) and zinc (Zn) and analyze the subcellular distribution and chemical speciation of Zn and Ph in different parts of plants, under different modifier concentrations (CK group: 100% lead-zinc slag plus a small amount of phosphate fertilizer, improved one: 85% of lead-zinc slag ± 10% peat ± 5% bacterial manure plus a small amount of phosphate fertilizer, improved two: 75% lead-zinc slag ± 20% peat ± 5% bacterial manure ± a small amount of phosphate). Results showed that: (1) The content of Pb, Zn in matrix after planting four kinds of plants was lower than before, no significant difference between improved one and improved two of Nerium oleander and Boehmeria was found, but improved two was better than improved one of Paulownia, while improved one was better than improved two of Koelreuteria paniculata; Four plants had relatively low aboveground enrichment coefficient of Pb and Zn, but had a high transfer coefficient, showed that the appropriate modifier concentration was able to improve the Pb and Zn enrichment and transfer ability of plants. (2) In subcellular distribution, most of Pb and Zn were distributed in plant cell wall components and soluble components while the distribution in cell organelles such as mitochondria, chloroplasts and nucleus component were less. Compared with CK group, two improved group made soluble components of the cell walls of Pb fixation and retention of zinc role in the enhancement. (3) As for the chemical forms of Pb and Zn in plants, the main chemical forms of Pb were hydrochloric acid, sodium chloride and ethanol extractable forms, while other chemical form contents were few, the main chemical forms of Zn were different based on plant type. Compared with CK group, the proportion of the active Pb chemical form in different plant

  5. Role of cobalt, iron, lead, manganese, mercury, platinum, selenium, and titanium in carcinogenesis.

    PubMed Central

    Kazantzis, G

    1981-01-01

    The possible carcinogenicity of cobalt, iron, lead, manganese, mercury, platinum, selenium, and titanium is reviewed, taking into account epidemiological data, the results of animal experimental studies, data on mutagenic effects and on other in vitro test systems. Of the great variety of occupations where exposure to one of these metals may occur, only haematite mining has been clearly shown to involve an increased human cancer risk. While the possibility that haematite might in some way act as a carcinogen has to be taken into consideration it is more likely that other carcinogens are responsible. Certain platinum coordination complexes are used in cancer chemotherapy, are mutagenic, and likely to be carcinogenic. Cobalt, its oxide and sulfide, certain lead salts, one organomanganese, and one organotitanium compound have been shown to have a limited carcinogenic effect in experimental animal studies, and except for titanium appear to be mutagenic. Certain mercury compounds are mutagenic but none have been shown to be carcinogenic. The presently available data are inadequate to assess the possible carcinogenicity of selenium compounds, but a few observations suggest that selenium may suppress the effect of other carcinogens administered to experimental animals and may even be associated with lower cancer mortality rates in man. Epidemiological observations are essential for the assessment of a human cancer risk, but the difficulty in collecting past exposure data in occupational groups and the complexity of multiple occupational exposures with changes over time, limits the usefulness of retrospective epidemiological studies. PMID:7023929

  6. Modelling drivers and distribution of lead and zinc concentrations in soils of an urban catchment (Sydney estuary, Australia).

    PubMed

    Johnson, L E; Bishop, T F A; Birch, G F

    2017-11-15

    The human population is increasing globally and land use is changing to accommodate for this growth. Soils within urban areas require closer attention as the higher population density increases the chance of human exposure to urban contaminants. One such example of an urban area undergoing an increase in population density is Sydney, Australia. The city also possesses a notable history of intense industrial activity. By integrating multiple soil surveys and covariates into a linear mixed model, it was possible to determine the main drivers and map the distribution of lead and zinc concentrations within the Sydney estuary catchment. The main drivers as derived from the model included elevation, distance to main roads, main road type, soil landscape, population density (lead only) and land use (zinc only). Lead concentrations predicted using the model exceeded the established guideline value of 300mgkg -1 over a large portion of the study area with concentrations exceeding 1000mgkg -1 in the south of the catchment. Predicted zinc did not exceed the established guideline value of 7400mgkg -1 ; however concentrations were higher to the south and west of the study area. Unlike many other studies we considered the prediction uncertainty when assessing the contamination risk. Although the predictions indicate contamination over a large area, the broadness of the prediction intervals suggests that in many of these areas we cannot be sure that the site is contaminated. More samples are required to determine the contaminant distribution with greater precision, especially in residential areas where contamination was highest. Managing sources and addressing areas of elevated lead and zinc concentrations in urban areas has the potential to reduce the impact of past human activities and improve the urban environment of the future. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Association of blood lead and mercury with estimated GFR in herbalists after the ban of herbs containing aristolochic acids in Taiwan.

    PubMed

    Lin, Hsing-Hua; Chou, Shan-An; Yang, Hsiao-Yu; Hwang, Yaw-Huei; Kuo, Ching-Hua; Kao, Tze-Wah; Lo, Tsai-Chang; Chen, Pau-Chung

    2013-08-01

    This study was undertaken to explore the association of estimated glomerular filtration rate (GFR) with exposure to aristolochic acids (ALAs) and nephrotoxic metals in herbalists after the ban of herbs containing ALAs in Taiwan. This cross-sectional study recruited a total of 138 herbalists without end-stage renal disease or urothelial carcinoma from the Occupational Union of Chinese Herbalists in Taiwan in 2007. Aristolochic acid I (ALA-I) was measured by ultra-high-pressure liquid chromatography/ tandem mass spectrometry (UHPLC-MS/MS) and heavy metals in blood samples were analysed by Agilent 7500C inductively coupled plasma-mass spectrometry. Renal function was assessed by using a simplified Modification of Diet in Renal Disease Study equation to estimate GFR. Blood lead was higher in herbal dispensing procedures (p=0.053) and in subjects who self-prescribe herbal medicine (p=0.057); mercury was also higher in subjects living in the workplace (p=0.03). Lower estimated GFR was significantly associated with lead (β=-10.66, 95% CI -18.7 to -2.6) and mercury (β=-12.52, 95% CI -24.3 to -0.8) with a significant interaction (p=0.01) between mercury and lead; however, estimated GFR was not significantly associated with high ALA-I level groups, arsenic and cadmium after adjusting for other confounding factors. We found that lower estimated GFR was associated with blood lead and mercury in herbalists after the ban of herbs containing ALAs in Taiwan. The ALA-I exposure did not show a significant negative association of estimated GFR, which might due to herbalists having known how to distinguish ALA herbs after the banning policy. Rigorous monitoring is still needed to protect herbalists and the general population who take herbs.

  8. Cadmium, lead, and mercury exposure assessment among croatian consumers of free-living game.

    PubMed

    Lazarus, Maja; Prevendar Crnić, Andreja; Bilandžić, Nina; Kusak, Josip; Reljić, Slaven

    2014-09-29

    Free-living game can be an important source of dietary cadmium and lead; the question is whether exposure to these two elements is such that it might cause adverse health effects in the consumers. The aim of this study was to estimate dietary exposure to cadmium, lead, and mercury from free-living big game (fallow deer, roe deer, red deer, wild boar, and brown bear), and to mercury from small game (pheasant and hare), hunted in Croatia from 1990 to 2012. The exposure assessment was based on available literature data and our own measurements of metal levels in the tissues of the game, by taking into account different consumption frequencies (four times a year, once a month and once a week). Exposure was expressed as percentage of (provisional) tolerable weekly intake [(P)TWI] values set by the European Food Safety Authority (EFSA). Consumption of game meat (0.002-0.5 % PTWI) and liver (0.005-6 % PTWI) assumed for the general population (four times a year) does not pose a health risk to consumers from the general population, nor does monthly (0.02-6 % PTWI) and weekly (0.1-24 % PTWI) consumption of game meat. However, because of the high percentage of free-living game liver and kidney samples exceeding the legislative limits for cadmium (2-99 %) and lead (1-82 %), people should keep the consumption of certain game species' offal as low as possible. Children and pregnant and lactating women should avoid eating game offal altogether. Free-living game liver could be an important source of cadmium if consumed on a monthly basis (3-74 % TWI), and if consumed weekly (11-297 % TWI), it could even give rise to toxicological concern.

  9. Review of Lead-Zinc Mining Impact on Landscape in the Tri-State Mining District using Small Unmanned Aerial Vehicles.

    NASA Astrophysics Data System (ADS)

    Bhakta, K. D.; Yeboah-Forson, A.

    2015-12-01

    The Tri-State lead and zinc mining district in SW Missouri, SE Kansas, and NE Oklahoma encompasses nearly 2,500 sq. miles of land and at its peak accounted for half of the US zinc (23,000,000 tons) production that surpassed one billion dollars in economic value. Once these lead and zinc rich ores were extracted, mining and milling sites were abandoned leaving behind a new landscape with numerous environmental challenges. Since 1970, most of the sites have been targeted for remediation and reclamation by federal and state agencies including the EPA. In order to capture the full extent of the impact of lead and zinc mining in the Tri-State area, numerous geoscientific approaches including data from small unmanned aerial vehicle (UAV) were employed to investigate the influence of mining in the study area. The study presented here is focused on observational assessment of the existing landscape using multiple commercial high-definitions data from UAVs to study different sites across areas of concern in the three states. Primary results (images) gathered and analyzed DEM and GIS data from abandoned mines showed the potential to provide a quick snapshot of successful or unsuccessful remediated areas. Although research and remediation of the Tri-State mining district are a continuous process, evidence from this geomorphic study suggest that UAVs can provide a quick overview of the remediated landscape or serve as a primary background tool for a more detail site-specific environmental study.

  10. Effects of Lead and Mercury on Sulfate-Reducing Bacterial Activity in a Biological Process for Flue Gas Desulfurization Wastewater Treatment

    NASA Astrophysics Data System (ADS)

    Zhang, Liang; Lin, Xiaojuan; Wang, Jinting; Jiang, Feng; Wei, Li; Chen, Guanghao; Hao, Xiaodi

    2016-07-01

    Biological sulfate-reducing bacteria (SRB) may be effective in removing toxic lead and mercury ions (Pb(II) and Hg(II)) from wet flue gas desulfurization (FGD) wastewater through anaerobic sulfite reduction. To confirm this hypothesis, a sulfite-reducing up-flow anaerobic sludge blanket reactor was set up to treat FGD wastewater at metal loading rates of 9.2 g/m3-d Pb(II) and 2.6 g/m3-d Hg(II) for 50 days. The reactor removed 72.5 ± 7% of sulfite and greater than 99.5% of both Hg(II) and Pb(II). Most of the removed lead and mercury were deposited in the sludge as HgS and PbS. The contribution of cell adsorption and organic binding to Pb(II) and Hg(II) removal was 20.0 ± 0.1% and 1.8 ± 1.0%, respectively. The different bioavailable concentration levels of lead and mercury resulted in different levels of lethal toxicity. Cell viability analysis revealed that Hg(II) was less toxic than Pb(II) to the sludge microorganisms. In the batch tests, increasing the Hg(II) feeding concentration increased sulfite reduction rates. In conclusion, a sulfite-reducing reactor can efficiently remove sulfite, Pb(II) and Hg(II) from FGD wastewater.

  11. Effects of Lead and Mercury on Sulfate-Reducing Bacterial Activity in a Biological Process for Flue Gas Desulfurization Wastewater Treatment

    PubMed Central

    Zhang, Liang; Lin, Xiaojuan; Wang, Jinting; Jiang, Feng; Wei, Li; Chen, Guanghao; Hao, Xiaodi

    2016-01-01

    Biological sulfate-reducing bacteria (SRB) may be effective in removing toxic lead and mercury ions (Pb(II) and Hg(II)) from wet flue gas desulfurization (FGD) wastewater through anaerobic sulfite reduction. To confirm this hypothesis, a sulfite-reducing up-flow anaerobic sludge blanket reactor was set up to treat FGD wastewater at metal loading rates of 9.2 g/m3-d Pb(II) and 2.6 g/m3-d Hg(II) for 50 days. The reactor removed 72.5 ± 7% of sulfite and greater than 99.5% of both Hg(II) and Pb(II). Most of the removed lead and mercury were deposited in the sludge as HgS and PbS. The contribution of cell adsorption and organic binding to Pb(II) and Hg(II) removal was 20.0 ± 0.1% and 1.8 ± 1.0%, respectively. The different bioavailable concentration levels of lead and mercury resulted in different levels of lethal toxicity. Cell viability analysis revealed that Hg(II) was less toxic than Pb(II) to the sludge microorganisms. In the batch tests, increasing the Hg(II) feeding concentration increased sulfite reduction rates. In conclusion, a sulfite-reducing reactor can efficiently remove sulfite, Pb(II) and Hg(II) from FGD wastewater. PMID:27455890

  12. Application of X-Ray Fluorescence Analysis to Determine the Elemental Composition of Tissues from Different Ovarian Neoplasms

    NASA Astrophysics Data System (ADS)

    Motevich, I. G.; Strekal, N. D.; Papko, N. M.; Glebovich, M. I.; Shulha, A. V.; Maskevich, S. A.

    2015-03-01

    We present the results of x-ray fluorescence analysis of tissues from healthy ovaries and from ovaries with different pathologies: benign and borderline tumors, mucinous and endometrioid cancers, serous carcinomas. We determine the average copper, zinc, calcium, selenium, cadmium, lead, and mercury levels. We observed that in the benign ovarian tumors, we see a significant decrease in the cadmium, mercury, and lead levels compared with healthy tissues. In the borderline neoplasms, the copper level is reduced relative to zinc (Cu/Zn), cadmium, mercury, and lead, and also the zinc concentration is increased. In the ovarian carcinomas, we observed changes in the ratio of the chemical elements in the tumor tissues, depending on the histologic type. The results obtained can be used for differentiation, diagnosis, and adjustment of treatment for different ovarian neoplasms.

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

    PubMed

    Meagher, Richard B; Heaton, Andrew C P

    2005-12-01

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

  14. THE ROLE OF ENVIRONMENTAL MERCURY, LEAD AND PESTICIDE EXPOSURE IN DEVELOPMENT OF AMYOTROPHIC LATERAL SCLEROSIS

    PubMed Central

    Johnson, Frank O.; Atchison, William

    2009-01-01

    Exposure to an environmental toxicant as a risk factor in the development of amyotrophic lateral sclerosis (ALS) was first hinted (demonstrated) in the Chamorro indigenous people of Guam. During the 1950s and 1960s these indigenous people presented an extremely high incidence of ALS which was presumed to be associated with the consumption of flying fox and cycad seeds. No other strong association between ALS and environmental toxicants has since been reported, although circumstantial epidemiological evidence has implicated exposure to heavy metals such as lead and mercury, industrial solvents and exposure to pesticides especially organophosphates and certain occupations such as playing soccer. Given that only ~10% of all ALS diagnosis has a genetic basis, a gene-environmental interaction provides a plausible explanation for the other 90% of cases. This mini-review provides an overview of our current knowledge of environmental etiologies of ALS with emphasis on the effects of mercury, lead and pesticides as potential risk factors in developing ALS. Epidemiologic and experimental evidence from animal models investigating the possible association between exposure to environmental toxicant and ALS disease has proven inconclusive. Nonetheless, there are indications that there may be causal links, and a need for more research. PMID:19632272

  15. Structural and Thermodynamic Consequences of the Replacement of Zinc with Environmental Metals on ERα-DNA Interactions

    PubMed Central

    Deegan, Brian J.; Bona, Anna M.; Bhat, Vikas; Mikles, David C.; McDonald, Caleb B.; Seldeen, Kenneth L.; Farooq, Amjad

    2011-01-01

    Estrogen receptor α (ERα) acts as a transcription factor by virtue of the ability of its DNA-binding (DB) domain, comprised of a tandem pair of zinc fingers, to recognize the estrogen response element (ERE) within the promoters of target genes. Herein, using an array of biophysical methods, we probe structural consequences of the replacement of zinc within the DB domain of ERα with various environmental metals and their effects on the thermodynamics of binding to DNA. Our data reveal that while the DB domain reconstituted with divalent ions of zinc, cadmium, mercury and cobalt binds to DNA with affinities in the nanomolar range, divalent ions of barium, copper, iron, lead, manganese, nickel and tin are unable to regenerate DB domain with DNA-binding potential though they can compete with zinc for coordinating the cysteine ligands within the zinc fingers. We also show that the metal-free DB domain is a homodimer in solution and that the binding of various metals only results in subtle secondary and tertiary structural changes, implying that metal-coordination may only be essential for DNA-binding. Collectively, our findings provide mechanistic insights into how environmental metals may modulate the physiological function of a key nuclear receptor involved in mediating a plethora of cellular functions central to human health and disease. PMID:22038807

  16. Mississippi Valley-type lead-zinc deposits through geological time: Implications from recent age-dating research

    USGS Publications Warehouse

    Leach, D.L.; Bradley, D.; Lewchuk, Michael T.; Symons, David T. A.; De Marsily, G.; Brannon, J.

    2001-01-01

    Remarkable advances in age dating Mississippi Valley-type (MVT) lead-zinc deposits provide a new opportunity to understand how and where these deposits form in the Earth's crust. These dates are summarized and examined in a framework of global tectonics, paleogeography, fluid migration, and paleoclimate. Nineteen districts have been dated by paleomagnetic and/or radiometric methods. Of the districts that have both paleomagnetic and radiometric dates, only the Pine Point and East Tennessee districts have significant disagreements. This broad agreement between paleomagnetic and radiometric dates provides added confidence in the dating techniques used. The new dates confirm the direct connection between the genesis of MVT lead-zinc ores with global-scale tectonic events. The dates show that MVT deposits formed mainly during large contractional tectonic events at restricted times in the history of the Earth. Only the deposits in the Lennard Shelf of Australia and Nanisivik in Canada have dates that correspond to extensional tectonic events. The most important period for MVT genesis was the Devonian to Permian time, which corresponds to a series of intense tectonic events during the assimilation of Pangea. The second most important period for MVT genesis was Cretaceous to Tertiary time when microplate assimilation affected the western margin of North America and Africa-Eurasia. There is a notable paucity of MVT lead-zinc ore formation following the breakup of Rodinia and Pangea. Of the five MVT deposits hosted in Proterozoic rocks, only the Nanisivik deposit has been dated as Proterozoic. The contrast in abundance between SEDEX and MVT lead-zinc deposits in the Proterozoic questions the frequently suggested notion that the two types of ores share similar genetic paths. The ages of MVT deposits, when viewed with respect to the orogenic cycle in the adjacent orogen suggest that no single hydrologic model can be universally applied to the migration of the ore fluids

  17. Mercury and other Mining-Related Contaminants in Ospreys along the Upper Clark Fork River, MT

    NASA Astrophysics Data System (ADS)

    Langner, H.; Domenech, R.; Greene, E.; Staats, M. F.

    2010-12-01

    Osprey (Pandion haliaetus) are widely recognized as bio-indicators of the health of aquatic ecosystems. Until the time of fledging, nestlings feed exclusively on fish caught within a few kilometers of the nest. Therefore, tissues of these young birds may reflect the level of contamination of local fish and more generally, the contamination status of the aquatic ecosystem they inhabit. Nests can often be accessed with a boom truck and obtaining small blood samples from the flightless chicks is fairly noninvasive. Ospreys are nesting along the Upper Clark Fork River, Montana, which is heavily contaminated with wastes left from a century of copper and precious metals mining. We have been monitoring the levels of priority pollutants (arsenic, cadmium, lead, copper, zinc, mercury and selenium) in Osprey chicks along a 250 km section of the river for four years. Objectives are to establish current contaminant status, pinpoint pollution hotspots, and assess the success of restoration efforts. Our results suggest that of highest concern may be the bioaccumulation of mercury with blood levels of up to 0.7 mg/L in the growing chicks. These concentrations are expected to increase many fold upon fledging as feather growth stops, which acts as the major sink for mercury. Interestingly, we found mercury levels increased in downstream direction, in contrast to concentrations of other pollutants. Reasons may be the different origin of mercury versus other contaminants and the distribution of wetlands where mercury can be transformed into highly bioavailable methylmercury. Blood levels of selenium are also elevated throughout the Upper Clark Fork River drainage. We discuss the implications for restoration and remediation of the Clark Fork River.

  18. 40 CFR 421.253 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0.364 0.169 Mercury 0.195 0.078 Silver 0.377 0.156 Zinc 1.326 0.546 Gold 0.130 (b) Silver... reduced in solution Lead 0.112 0.052 Mercury 0.060 0.024 Silver 0.116 0.048 Zinc 0.408 0.168 Gold 0.040 (c...

  19. 40 CFR 421.253 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0.364 0.169 Mercury 0.195 0.078 Silver 0.377 0.156 Zinc 1.326 0.546 Gold 0.130 (b) Silver... reduced in solution Lead 0.112 0.052 Mercury 0.060 0.024 Silver 0.116 0.048 Zinc 0.408 0.168 Gold 0.040 (c...

  20. 40 CFR 421.253 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0.364 0.169 Mercury 0.195 0.078 Silver 0.377 0.156 Zinc 1.326 0.546 Gold 0.130 (b) Silver... reduced in solution Lead 0.112 0.052 Mercury 0.060 0.024 Silver 0.116 0.048 Zinc 0.408 0.168 Gold 0.040 (c...

  1. Concentrations and sources of cadmium, copper, lead and zinc in house dust in Christchurch, New Zealand.

    PubMed

    Kim, N; Fergusson, J

    1993-09-30

    The amounts (microgram m-2) and concentrations (microgram g-1) of cadmium, copper, lead and zinc have been measured in house dust in Christchurch, New Zealand. For 120 houses surveyed the geometric mean concentrations of the four metals are 4.24 micrograms g-1, 165 micrograms g-1, 573 micrograms g-1 and 10,400 micrograms g-1, respectively. In addition eleven variables, such as house age, carpet wear and traffic density, were recorded for each property and the results analysed with respect to their effects on the amounts and concentrations of the four elements. The amounts of all the metals were highly correlated with the overall dustiness of the houses, which was found to be predominantly determined by the degree of carpet wear. No one dominant source of cadmium was identified, although several minor sources including carpet wear, galvanized iron roofs and red/orange/yellow coloured carpets were implicated. Petrol lead and lead-based paints were identified as significant sources of lead in house dust. Rubber carpet underlays or backings were identified as a significant source of zinc, with some contribution from galvanized iron roofs. Road traffic and probably the existence of a fire place appear to contribute to the copper levels.

  2. Annual trace-metal load estimates and flow-weighted concentrations of cadmium, lead, and zinc in the Spokane River basin, Idaho and Washington, 1999-2004

    USGS Publications Warehouse

    Donato, Mary M.

    2006-01-01

    Streamflow and trace-metal concentration data collected at 10 locations in the Spokane River basin of northern Idaho and eastern Washington during 1999-2004 were used as input for the U.S. Geological Survey software, LOADEST, to estimate annual loads and mean flow-weighted concentrations of total and dissolved cadmium, lead, and zinc. Cadmium composed less than 1 percent of the total metal load at all stations; lead constituted from 6 to 42 percent of the total load at stations upstream from Coeur d'Alene Lake and from 2 to 4 percent at stations downstream of the lake. Zinc composed more than 90 percent of the total metal load at 6 of the 10 stations examined in this study. Trace-metal loads were lowest at the station on Pine Creek below Amy Gulch, where the mean annual total cadmium load for 1999-2004 was 39 kilograms per year (kg/yr), the mean estimated total lead load was about 1,700 kg/yr, and the mean annual total zinc load was 14,000 kg/yr. The trace-metal loads at stations on North Fork Coeur d'Alene River at Enaville, Ninemile Creek, and Canyon Creek also were relatively low. Trace-metal loads were highest at the station at Coeur d'Alene River near Harrison. The mean annual total cadmium load was 3,400 kg/yr, the mean total lead load was 240,000 kg/yr, and the mean total zinc load was 510,000 kg/yr for 1999-2004. Trace-metal loads at the station at South Fork Coeur d'Alene River near Pinehurst and the three stations on the Spokane River downstream of Coeur d'Alene Lake also were relatively high. Differences in metal loads, particularly lead, between stations upstream and downstream of Coeur d'Alene Lake likely are due to trapping and retention of metals in lakebed sediments. LOADEST software was used to estimate loads for water years 1999-2001 for many of the same sites discussed in this report. Overall, results from this study and those from a previous study are in good agreement. Observed differences between the two studies are attributable to streamflow

  3. Lead, mercury, cadmium, chromium, and arsenic levels in eggs, feathers, and tissues of Canada geese of the New Jersey Meadowlands

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsipoura, Nellie; Burger, Joanna, E-mail: burger@biology.rutgers.edu; Environmental and Occupational Health Sciences Institute, Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ 08854

    2011-08-15

    The New Jersey Meadowlands are located within the heavily urbanized New York/New Jersey Harbor Estuary and have been subject to contamination due to effluent and runoff from industry, traffic, and homes along the Hackensack River and nearby waterways. These extensive wetlands, though heavily impacted by development and pollution, support a wide array of bird and other wildlife species. Persistent contaminants may pose threats to birds in these habitats, affecting reproduction, egg hatchability, nestling survival, and neurobehavioral development. Metals of concern in the Meadowlands include arsenic, cadmium, chromium, lead, and mercury. These metals were analyzed in eggs, feathers, muscle, and livermore » of Canada geese (Branta canadensis) breeding in four wetland sites. We sampled geese collected during control culling (n=26) and collected eggs from goose nests (n=34). Levels of arsenic were below the minimum quantification level (MQL) in most samples, and cadmium and mercury were low in all tissues sampled. Chromium levels were high in feather samples. Mercury levels in eggs of Canada geese, an almost exclusively herbivorous species, were lower (mean {+-}SE 4.29{+-}0.30 {mu}g/g wet weight) than in eggs of omnivorous mallards (Anas platyrhynchos), and insectivorous red-winged blackbirds (Agelaius phoeniceus) and marsh wrens (Cistothorus palustris) from the Meadowlands, consistent with trophic level differences. However, lead levels were higher in the goose eggs (161{+-}36.7 ng/g) than in the other species. Geese also had higher levels of lead in feathers (1910{+-}386 ng/g) than those seen in Meadowlands passerines. By contrast, muscle and liver lead levels were within the range reported in waterfowl elsewhere, possibly a reflection of metal sequestration in eggs and feathers. Elevated lead levels may be the result of sediment ingestion or ingestion of lead shot and sinkers. Finally, lead levels in goose liver (249{+-}44.7 ng/g) and eggs (161{+-}36.7 ng/g) may

  4. Sources of lead and zinc associated with metal smelting activities in the Trail area, British Columbia, Canada.

    PubMed

    Goodarzi, Fariborz; Sanei, Hamed; Labonté, Marcel; Duncan, William F

    2002-06-01

    The spatial distribution and deposition of lead and zinc emitted from the Trail smelter, British Columbia, Canada, was studied by strategically locating moss bags in the area surrounding the smelter and monitoring the deposition of elements every three months. A combined diffusion/distribution model was applied to estimate the relative contribution of stack-emitted material and material emitted from the secondary sources (e.g., wind-blown dust from ore/slag storage piles, uncovered transportation/trucking of ore, and historical dust). The results indicate that secondary sources are the major contributor of lead and zinc deposited within a short distance from the smelter. Gradually, the stack emissions become the main source of Pb and Zn at greater distances from the smelter. Typical material originating from each source was characterized by SEM/EDX, which indicated a marked difference in their morphology and chemical composition.

  5. Zinc in Infection and Inflammation.

    PubMed

    Gammoh, Nour Zahi; Rink, Lothar

    2017-06-17

    Micronutrient homeostasis is a key factor in maintaining a healthy immune system. Zinc is an essential micronutrient that is involved in the regulation of the innate and adaptive immune responses. The main cause of zinc deficiency is malnutrition. Zinc deficiency leads to cell-mediated immune dysfunctions among other manifestations. Consequently, such dysfunctions lead to a worse outcome in the response towards bacterial infection and sepsis. For instance, zinc is an essential component of the pathogen-eliminating signal transduction pathways leading to neutrophil extracellular traps (NET) formation, as well as inducing cell-mediated immunity over humoral immunity by regulating specific factors of differentiation. Additionally, zinc deficiency plays a role in inflammation, mainly elevating inflammatory response as well as damage to host tissue. Zinc is involved in the modulation of the proinflammatory response by targeting Nuclear Factor Kappa B (NF-κB), a transcription factor that is the master regulator of proinflammatory responses. It is also involved in controlling oxidative stress and regulating inflammatory cytokines. Zinc plays an intricate function during an immune response and its homeostasis is critical for sustaining proper immune function. This review will summarize the latest findings concerning the role of this micronutrient during the course of infections and inflammatory response and how the immune system modulates zinc depending on different stimuli.

  6. Chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures

    USGS Publications Warehouse

    Wang, Ning; Ingersoll, Christopher G.; Dorman, Rebecca A.; Brumbaugh, William G.; Mebane, Christopher A.; Kunz, James L.; Hardesty, Douglas K.

    2014-01-01

    Chronic toxicity of cadmium, copper, lead, or zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) was evaluated in water-only exposures started with newly hatched larvae or approximately 1-mo-old juveniles. The 20% effect concentration (EC20) for cadmium from the sturgeon tests was higher than the EC20 from the trout tests, whereas the EC20 for copper, lead, or zinc for the sturgeon were lower than those EC20s for the trout. When the EC20s from the present study were included in compiled toxicity databases for all freshwater species, species mean chronic value for white sturgeon was in a relatively low percentile of the species sensitivity distribution for copper (9th percentile) and in the middle percentile for cadmium (55th percentile), zinc (40th percentile), or lead (50th percentile). However, the species mean chronic value for rainbow trout was in a high percentile for copper, lead, and zinc (∼68th–82nd percentile), but in a low percentile for cadmium (23rd percentile). The trout EC20s for each of the 4 metals and the sturgeon EC20s for cadmium or lead were above US Environmental Protection Agency chronic ambient water quality criteria (AWQC) or Washington State chronic water quality standards (WQS), whereas the sturgeon EC20s for copper or zinc were approximately equal to or below the chronic AWQC and WQS. In addition, acute 50% effect concentrations (EC50s) for copper obtained in the first 4 d of the chronic sturgeon test were below the final acute value used to derive acute AWQC and below acute WQS for copper.

  7. Lead and mercury in fall migrant golden eagles from western North America.

    PubMed

    Langner, Heiko W; Domenech, Robert; Slabe, Vincent A; Sullivan, Sean P

    2015-07-01

    Lead exposure from ingestion of bullet fragments is a serious environmental hazard to eagles. We determined blood lead levels (BLL) in 178 golden eagles (Aquila chrysaetos) captured during fall migration along a major North American flyway. These eagles spent the breeding season distributed over a large range and are the best currently available representation of free flying golden eagles on the continent. We found 58 % of these eagles containing increased BLL > 0.1 mg/L; 10 % were clinically lead poisoned with BLL > 0.6 mg/L; and 4 % were lethally exposed with BLL > 1.2 mg/L. No statistical difference in BLL existed between golden and bald eagles (Haliaeetus leucocephalus). Golden eagles captured on carrion had higher BLL than those captured using live bait suggesting differences in feeding habits among individuals. Median BLL increased with age class. We propose a conceptual model for the long-term increase in BLL after ingestion of lead particles. The mean blood mercury level in golden eagles was 0.023 mg/L. We evaluate a field test for BLL that is based on anodic stripping voltammetry. This cost-effective and immediate method correlated well with results from inductively coupled plasma-mass spectrometry, although results needed to be corrected for each calibration of the test kit.

  8. Differential toxicity of copper, zinc, and lead during the embryonic development of Chasmagnathus granulatus (Brachyura, Varunidae).

    PubMed

    Lavolpe, Mariano; Greco, Laura López; Kesselman, Daniela; Rodríguez, Enrique

    2004-04-01

    Ovigerous females of the estuarine crab Chasmagnathus granulatus were exposed to copper (0.01 and 1 mg/L), zinc (0.05, 1, and 10 mg/L), or lead (0.01 and 1 mg/L) during early, late, or whole embryonic development. None of the assayed heavy metals produced a significant mortality of females, neither a decrease in the number of hatched larvae nor a decrease in the egg incubation time, but several morphological abnormalities were detected in hatched larvae. The abnormalities were classified in three categories: eye, body pigmentary, and body morphological abnormalities. Those larvae with eye and body pigmentary abnormalities, particularly those involving retinal pigments and chromatophores, showed the highest incidence by exposure to the assayed metals. In addition, embryos were more susceptible to copper and zinc during the late period of development, whereas the effect of lead was greater during the early period of embryogenesis. Some teratogenic effects observed in C. granulatus embryos exposed to heavy metals, particularly the hypertrophy and hypopigmentation of eyes observed in the laboratory at a lead concentration as low as that reported for the natural environment, could be considered as sensitive biomarkers for this kind of pollutant.

  9. Lead poisoning and trace elements in common eiders Somateria mollissima from Finland

    USGS Publications Warehouse

    Hollmén, Tuula E.; Franson, J.C.; Poppenga, R.H.; Hario, Martti; Kilpi, Mikael

    1998-01-01

    We collected carcasses of 52 common eider Somateria mollissima adults and ducklings and blood samples from 11 nesting eider hens in the Gulf of Finland near Helsinki in 1994, 1995 and 1996. Samples of liver tissue were analysed for arsenic, cadmium, chromium, copper, iron, lead, magnesium, manganese, mercury, molybdenum, selenium and zinc. Blood was analysed for lead, mercury and selenium. Most of the 21 adults examined at necropsy were emaciated with empty gizzards, and no ingested shotgun pellets or other metal were found in any of the birds. Three adult females had a combination of lesions and tissue lead residues characteristic of lead poisoning. Two of these birds had acid-fast intranuclear inclusion bodies in renal epithelial cells and high concentrations of lead (73.4 and 73.3 ppm; all liver residues reported on dry weight basis) in their livers. The third was emaciated with a liver lead concentration of 47.9 ppm. An adult male had a liver lead concentration of 81.7 ppm, which is consistent with severe clinical poisoning. Two other adults, one male and one female, had liver lead concentrations of 14.2 and 8.03 ppm, respectively. Lead concentrations in the blood of hens ranged from 0.11 to 0.63 ppm wet weight. Selenium residues of A?60 ppm were found in the livers of five adult males. Selenium concentrations in the blood of hens ranged from 1.18 to 3.39 ppm wet weight. Arsenic concentrations of 27.5-38.5 ppm were detected in the livers of four adult females. Detectable concentrations of selenium, mercury and molybdenum were found more frequently in the livers of adult males arriving on the breeding grounds than in incubating females, while the reverse was true for arsenic, lead and chromium. Mean concentrations of selenium, copper and molybdenum were higher in the livers of arriving males than in the livers of incubating hens, but hens had greater concentrations of iron and magnesium. Concentrations of trace elements were lower in the livers of ducklings than

  10. The relationship between bone health and plasma zinc, copper lead and cadmium concentration in osteoporotic women.

    PubMed

    Sadeghi, Naficeh; Oveisi, Mohammad Reza; Jannat, Behrooz; Hajimahmoodi, Mannan; Behzad, Masoomeh; Behfar, Abdolazim; Sadeghi, Fatemeh; Saadatmand, Sahereh

    2014-01-01

    Osteoporosis is a multi factorial disease with dimension of genetic and nutritional considerations. The aim of this study was to present data from the association of plasma zinc, copper and toxic elements of lead and cadmium levels with bone mineral density in Iranian women. 135 women gave their information and enrolled. Fasting plasma was used for measurement of trace elements and heavy metals by Differential Pulse Anodic Stripping Voltammetry. Control group (n = 51) were normal in both lumbar spine (L1-L4) and femoral neck density (T-score ≥ -1), but just femoral neck T-score was considered as criterion in selection of patient group (n = 49, Tscore < -1). No differences were found in the nutritional status, number of diseases, drugs and functional activities between these groups. Plasma Zn, Cu, Pb, Cd levels were analyzed by, a method of voltammetry. Mean ± SD levels of copper and zinc was 1.168 ± 0.115, 1.097 ± 0.091 μg/ml in control group, 1.394 ± 0.133, 1.266 ± 0.11 μg/ml in total patient (TP) and 1.237 ± 0.182, 1.127 ± 0.176 μg/ml in Mild patients(-1 > T-score > -1.7), 1.463 ± 0.174, 1.327 ± 0.147 μg/ml in Severe patient group (T-score < -1.7); respectively. Mean ± SD plasma level of lead and cadmium was 168.42 ± 9.61 ng/l, 2.91 ± 0.18 ng/ml in control group, 176.13 ± 8.64 ng/l, 2.97 ± 0.21 ng/ml in TP, 176.43 ± 13.2 ng/l, 2.99 ± 0.1 ng/ml in mild patients, 221.44 ± 20 ng/l and 3.80 ± 0.70 ng/ml in severe patient group, respectively. In this study plasma zinc, copper, lead & cadmium concentrations were higher in the patients than in the control, though differences were not significant. However, differences were higher between the controls and patients with severe disease (T-score < -1.7). In addition adjusted T-score of femur with age and BMI showed negative significant correlation with plasma levels of zinc and lead in total participants (p < 0.05, r = -0.201, p = 0.044, r = -0.201). It seems that more extensive study with larger

  11. Zinc lozenges and the common cold: a meta-analysis comparing zinc acetate and zinc gluconate, and the role of zinc dosage.

    PubMed

    Hemilä, Harri

    2017-05-01

    To compare the efficacy of zinc acetate lozenges with zinc gluconate lozenges in common cold treatment and to examine the dose-dependency of the effect. Meta-analysis. Placebo-controlled zinc lozenge trials, in which the zinc dose was > 75 mg/day. The pooled effect of zinc lozenges on common cold duration was calculated by using inverse-variance random-effects method. Seven randomised trials with 575 participants with naturally acquired common colds. Duration of the common cold. The mean common cold duration was 33% (95% CI 21% to 45%) shorter for the zinc groups of the seven included trials. Three trials that used lozenges composed of zinc acetate found that colds were shortened by 40% and four trials that used zinc gluconate by 28%. The difference between the two salts was not significant: 12 percentage points (95% CI: -12 to + 36). Five trials used zinc doses of 80-92 mg/day, common cold duration was reduced by 33%, and two trials used zinc doses of 192-207 mg/day and found an effect of 35%. The difference between the high-dose and low-dose zinc trials was not significant: 2 percentage points (95% CI: -29 to + 32). Properly composed zinc gluconate lozenges may be as effective as zinc acetate lozenges. There is no evidence that zinc doses over 100 mg/day might lead to greater efficacy in the treatment of the common cold. Common cold patients may be encouraged to try zinc lozenges for treating their colds. The optimal lozenge composition and dosage scheme need to be investigated further.

  12. Adverse health effects in Canada geese (Branta canadensis) associated with waste from zinc and lead mines in the Tri-State Mining District (Kansas, Oklahoma, and Missouri, USA).

    PubMed

    van der Merwe, Deon; Carpenter, James W; Nietfeld, Jerome C; Miesner, John F

    2011-07-01

    Lead and zinc poisoning have been recorded in a variety of bird species, including migrating waterfowl such as Canada Geese (Branta canadensis), at sites contaminated with mine waste from lead and zinc mines in the Tri-State Mining District, Kansas, Oklahoma, and Missouri, USA. The adverse health impacts from mine waste on these birds may, however, be more extensive than is apparent from incidental reports of clinical disease. To characterize health impacts from mine waste on Canada Geese that do not have observable signs of poisoning, four to eight apparently healthy birds per site were collected from four contaminated sites and an uncontaminated reference site, and examined for physical and physiologic evidence of metals poisoning. Tissue concentrations of silver, aluminum, arsenic, barium, cadmium, cobalt, chromium, copper, iron, magnesium, manganese, molybdenum, nickel, lead, selenium, thallium, vanadium, and zinc were determined by inductively coupled plasma mass spectroscopy. Adverse health effects due to lead were characterized by assessing blood δ-aminolevulinic acid dehydratase (ALAD) enzyme activity. Adverse effects associated with zinc poisoning were determined from histologic examination of pancreas tissues. Elevated tissue lead concentrations and inhibited blood ALAD enzyme activities were consistently found in birds at all contaminated sites. Histopathologic signs of zinc poisoning, including fibrosis and vacuolization, were associated with elevated pancreatic zinc concentrations at one of the study sites. Adverse health effects associated with other analyzed elements, or tissue concentrations indicating potentially toxic exposure levels to these elements, were not observed.

  13. Formation of soluble mercury oxide coatings: Transformation of elemental mercury in soils

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miller, Carrie L.; Watson, David B.; Lester, Brian P.

    2015-09-21

    In this study, the impact of mercury (Hg) on human and ecological health has been known for decades. Although a treaty signed in 2013 by 147 nations regulates future large-scale mercury emissions, legacy Hg contamination exists worldwide and small-scale releases will continue. The fate of elemental mercury, Hg(0), lost to the subsurface and its potential chemical transformation that can lead to changes in speciation and mobility are poorly understood. Here, we show that Hg(0) beads interact with soil or manganese oxide solids and X-ray spectroscopic analysis indicates that the soluble mercury coatings are HgO. Dissolution studies show that, after reactingmore » with a composite soil, >20 times more Hg is released into water from the coated beads than from a pure liquid mercury bead. An even larger, >700 times, release occurs from coated Hg(0) beads that have been reacted with manganese oxide, suggesting that manganese oxides are involved in the transformation of the Hg(0) beads and creation of the soluble mercury coatings. Although the coatings may inhibit Hg(0) evaporation, the high solubility of the coatings can enhance Hg(II) migration away from the Hg(0)-spill site and result in potential changes in mercury speciation in the soil and increased mercury mobility.« less

  14. Assessment of water resources in lead-zinc mined areas in Cherokee County, Kansas, and adjacent areas

    USGS Publications Warehouse

    Spruill, Timothy B.

    1984-01-01

    A study was conducted to evaluate water-resources problems related to abandoned lead and zinc mines in Cherokee County, Kansas, and adjacent areas in Missouri and Oklahoma. Past mining activities have caused changes in the hydrogeology of the area. Lead and zinc mining has caused discontinuities and perforations in the confining shale west of the Pennsylvanian-Mississippian geologic contact (referred to as the western area), which have created artificial ground-water recharge and discharge areas. Recharge to the shallow aquifer (rocks of Mississippian age) through collapses, shafts, and drill holes in the shale has caused the formation of a groundwater "mound" in the vicinity of the Picher Field in Kansas and Oklahoma. Discharge of mine-contaminated ground water to Tar Creek occurs in'Oklahoma from drill holes and shafts where the potentiometric surface of the shallow aquifer is above the land surface. Mining of ore in the shallow aquifer has resulted in extensive fracturing and removal of material, which has created highly transmissive zones and voids and increased ground-water storage properties of the aquifer. In the area east of the Pennsylvanian-Mississippian geologic contact (referred to as the eastern area), fractured rock and tailings on the land surface increased the amount of water available for infiltration to the shallow aquifer; in the western area, tailings on the impermeable shale created artificial, perched aquifer systems that slowly drain to surface streams.Pumping of the deep aquifer (rocks of Cambrian and Ordovician age) by towns and industries, which developed as a result of the mining industry, has resulted in a potential for downward movement of water from the shallow aquifer. The potential is greatest in Ottawa County, Oklahoma. Because of the large volume of water that may be transported from the shallow to the deep aquifer, open drill holes or casings present the greatest contamination hazard to water supplies in the deep aquifer

  15. Zinc in Infection and Inflammation

    PubMed Central

    Gammoh, Nour Zahi; Rink, Lothar

    2017-01-01

    Micronutrient homeostasis is a key factor in maintaining a healthy immune system. Zinc is an essential micronutrient that is involved in the regulation of the innate and adaptive immune responses. The main cause of zinc deficiency is malnutrition. Zinc deficiency leads to cell-mediated immune dysfunctions among other manifestations. Consequently, such dysfunctions lead to a worse outcome in the response towards bacterial infection and sepsis. For instance, zinc is an essential component of the pathogen-eliminating signal transduction pathways leading to neutrophil extracellular traps (NET) formation, as well as inducing cell-mediated immunity over humoral immunity by regulating specific factors of differentiation. Additionally, zinc deficiency plays a role in inflammation, mainly elevating inflammatory response as well as damage to host tissue. Zinc is involved in the modulation of the proinflammatory response by targeting Nuclear Factor Kappa B (NF-κB), a transcription factor that is the master regulator of proinflammatory responses. It is also involved in controlling oxidative stress and regulating inflammatory cytokines. Zinc plays an intricate function during an immune response and its homeostasis is critical for sustaining proper immune function. This review will summarize the latest findings concerning the role of this micronutrient during the course of infections and inflammatory response and how the immune system modulates zinc depending on different stimuli. PMID:28629136

  16. Zinc-mediated Allosteric Inhibition of Caspase-6*

    PubMed Central

    Velázquez-Delgado, Elih M.; Hardy, Jeanne A.

    2012-01-01

    Zinc and caspase-6 have independently been implicated in several neurodegenerative disorders. Depletion of zinc intracellularly leads to apoptosis by an unknown mechanism. Zinc inhibits cysteine proteases, including the apoptotic caspases, leading to the hypothesis that zinc-mediated inhibition of caspase-6 might contribute to its regulation in a neurodegenerative context. Using inductively coupled plasma optical emission spectroscopy, we observed that caspase-6 binds one zinc per monomer, under the same conditions where the zinc leads to complete loss of enzymatic activity. To understand the molecular details of zinc binding and inhibition, we performed an anomalous diffraction experiment above the zinc edge. The anomalous difference maps showed strong 5σ peaks, indicating the presence of one zinc/monomer bound at an exosite distal from the active site. Zinc was not observed bound to the active site. The zinc in the exosite was liganded by Lys-36, Glu-244, and His-287 with a water molecule serving as the fourth ligand, forming a distorted tetrahedral ligation sphere. This exosite appears to be unique to caspase-6, as the residues involved in zinc binding were not conserved across the caspase family. Our data suggest that binding of zinc at the exosite is the primary route of inhibition, potentially locking caspase-6 into the inactive helical conformation. PMID:22891250

  17. Geochemical background of zinc, cadmium and mercury in anthropically influenced soils in a semi-arid zone (SE, Spain)

    NASA Astrophysics Data System (ADS)

    García-Lorenzo, M. L.; Pérez-Sirvent, C.; Martínez-Sánchez, M. J.; Molina, J.; Tudela, M. L.; Hernández-Córdoba, M.

    2009-04-01

    This work seeks to establish the geochemical background for three potentially toxic trace elements (Zn, Cd and Hg) in a pilot zone included in the DesertNet project in the province of Murcia. The studied area, known as Campo de Cartagena, Murcia (SE Spain) is an area of intensive agriculture and has been much affected over the years by anthropic activity. The zone can be considered an experimental pilot zone for establishing background levels in agricultural soils. Sixty four samples were collected and corresponded to areas subjected to high and similar agricultural activity or soils with natural vegetation, which correspond to abandoned agricultural areas. The Zn content was determined by flame atomic absorption spectrometry. The Cd content was determined by electrothermal atomization atomic absorption spectrometry and mercury content was determined by atomic fluorescence spectrometry. Geostatistical analysis consisting of kriging and mapping was performed using the geostatistical analyst extension of ArcGIS 8.3. Zinc values ranged from 10 mg kg-1 to 151 mg kg-1, with an average value of 45 mg kg-1. Cadmium values ranged between 0.1 mg kg-1 and 0.9mg kg-1, with a mean value of 0.3 mg kg-1 and mercury values ranged from 0.1 mg kg-1 to 2.3 mg kg-1, with a mean value of 0.5 mg kg-1. At a national level, the Spanish Royal Decree 9/2005 proposes toxicological and statistical approaches to establish background values. According to the statistical approach, background values consist of the median value for the selected element. The background values for Zn, Cd and Hg in the studied area were 40 mg kg-1 for Zn, 0.3 mg kg-1 for Cd and 0.4 mg kg-1 for Hg.

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

    PubMed

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

    2013-09-01

    Although fish intake has potential health benefits, the presence of metal contamination in seafood has raised public health concerns. In this study, levels of mercury, cadmium, lead, tin and arsenic have been determined in fresh, canned and frozen fish and shellfish products and compared with the maximum levels currently in force. In a further step, potential human health risks for the consumers were assessed. A total of 485 samples of the 43 most frequently consumed fish and shellfish species in Andalusia (Southern Spain) were analyzed for their toxic elements content. High mercury concentrations were found in some predatory species (blue shark, cat shark, swordfish and tuna), although they were below the regulatory maximum levels. In the case of cadmium, bivalve mollusks such as canned clams and mussels presented higher concentrations than fish, but almost none of the samples analyzed exceeded the maximum levels. Lead concentrations were almost negligible with the exception of frozen common sole, which showed median levels above the legal limit. Tin levels in canned products were far below the maximum regulatory limit, indicating that no significant tin was transferred from the can. Arsenic concentrations were higher in crustaceans such as fresh and frozen shrimps. The risk assessment performed indicated that fish and shellfish products were safe for the average consumer, although a potential risk cannot be dismissed for regular or excessive consumers of particular fish species, such as tuna, swordfish, blue shark and cat shark (for mercury) and common sole (for lead). Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Clinical assessment of pacemaker power sources

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bilitch, M.; Parsonnet, V.; Furman, S.

    1980-01-01

    The development of power sources for cardiac pacemakers has progressed from a 15-year usage of mercury-zinc batteries to widely used and accepted lithium cells. At present, there are about 6 different types of lithium cells incorporated into commercially distributed pacemakers. The authors reviewed experience over a 5-year period with 1711 mercury-zinc, 130 nuclear (P238) and 1912 lithium powered pacemakers. The lithium units have included 698 lithium-iodide, 270 lithium-silver chromate, 135 lithium-thionyl chloride, 31 lithium-lead and 353 lithium-cupric sulfide batteries. 57 of the lithium units have failed (91.2% component failure and 5.3% battery failure). 459 mercury-zinc units failed (25% component failuremore » and 68% battery depletion). The data show that lithium powered pacemaker failures are primarily component, while mercury-zinc failures are primarily battery related. It is concluded that mercury-zinc powered pulse generators are obsolete and that lithium and nuclear (P238) power sources are highly reliable over the 5 years for which data are available. 3 refs.« less

  20. Sediment-Hosted Zinc-Lead Deposits of the World - Database and Grade and Tonnage Models

    USGS Publications Warehouse

    Singer, Donald A.; Berger, Vladimir I.; Moring, Barry C.

    2009-01-01

    This report provides information on sediment-hosted zinc-lead mineral deposits based on the geologic settings that are observed on regional geologic maps. The foundation of mineral-deposit models is information about known deposits. The purpose of this publication is to make this kind of information available in digital form for sediment-hosted zinc-lead deposits. Mineral-deposit models are important in exploration planning and quantitative resource assessments: Grades and tonnages among deposit types are significantly different, and many types occur in different geologic settings that can be identified from geologic maps. Mineral-deposit models are the keystone in combining the diverse geoscience information on geology, mineral occurrences, geophysics, and geochemistry used in resource assessments and mineral exploration. Too few thoroughly explored mineral deposits are available in most local areas for reliable identification of the important geoscience variables, or for robust estimation of undiscovered deposits - thus, we need mineral-deposit models. Globally based deposit models allow recognition of important features because the global models demonstrate how common different features are. Well-designed and -constructed deposit models allow geologists to know from observed geologic environments the possible mineral-deposit types that might exist, and allow economists to determine the possible economic viability of these resources in the region. Thus, mineral-deposit models play the central role in transforming geoscience information to a form useful to policy makers. This publication contains a computer file of information on sediment-hosted zinc-lead deposits from around the world. It also presents new grade and tonnage models for nine types of these deposits and a file allowing locations of all deposits to be plotted in Google Earth. The data are presented in FileMaker Pro, Excel and text files to make the information available to as many as possible. The

  1. Assessment of water resources in lead-zinc mined areas in Cherokee County, Kansas, and adjacent areas

    USGS Publications Warehouse

    Spruill, Timothy B.

    1987-01-01

    A study was conducted to evaluate water-resources problems related to abandoned lead and zinc mines in Cherokee County, Kansas, and adjacent areas in Missouri and Oklahoma. Past mining activities have caused changes in the hydrogeology of the area. Lead and zinc mining has caused discontinuities and perforations in the confining shale west of the Pennsylvanian-Mississippian geologic contact (referred to as the western area), which have created artificial ground-water recharge and discharge areas. Recharge to the shallow aquifer (rocks of Mississippian age) through collapses, shafts, and drill holes in the shale has caused the formation of a ground-water 'mound' in the vicinity of the Picher Field in Kansas and Oklahoma. Discharge of mine-contaminated ground water to Tar Creek occurs in Oklahoma from drill holes and shafts where the potentiometric surface of the shallow aquifer is above the land surface. Mining of ore in the shallow aquifer has resulted in extensive fracturing and removal of material, which has created highly transmissive zones and voids and increased ground-water storage properties of the aquifer. In the area east of the Pennsylvanian-Mississippian geologic contact (referred to as the eastern area), fractured rock and tailings on the land surface increased the amount of water available for infiltration to the shallow aquifer; in the western area, tailings on the impermeable shale created artificial, perched aquifer systems that slowly drain to surface streams. Pumping of the deep aquifer (rocks of Cambrian and Ordovician age) by towns and industries, which developed as a result of the mining industry, has resulted in a potential for downward movement of water from the shallow aquifer. The potential is greatest in Ottawa County, Oklahoma. Because of the large volume of water that may be transported from the shallow to the deep aquifer, open drill holes or casings present the greatest contamination hazard to water supplies in the deep aquifer. Mining

  2. Sedimentary exhalative (sedex) zinc-lead-silver deposit model

    USGS Publications Warehouse

    Emsbo, Poul; Seal, Robert R.; Breit, George N.; Diehl, Sharon F.; Shah, Anjana K.

    2016-10-28

    This report draws on previous syntheses and basic research studies of sedimentary exhalative (sedex) deposits to arrive at the defining criteria, both descriptive and genetic, for sedex-type deposits. Studies of the tectonic, sedimentary, and fluid evolution of modern and ancient sedimentary basins have also been used to select defining criteria. The focus here is on the geologic characteristics of sedex deposit-hosting basins that contain greater than 10 million metric tons of zinc and lead. The enormous size of sedex deposits strongly suggests that basin-scale geologic processes are involved in their formation. It follows that mass balance constraints of basinal processes can provide a conceptual underpinning for the evaluation of potential ore-forming mechanisms and the identification of geologic indicators for ore potential in specific sedimentary basins. Empirical data and a genetic understanding of the physicochemical, geologic, and mass balance conditions required for each of these elements are used to establish a hierarchy of quantifiable geologic criteria that can be used in U.S. Geological Survey national assessments.  In addition, this report also provides a comprehensive evaluation of environmental considerations associated with the mining of sedex deposits.

  3. Assessment of metals in down feathers of female common eiders and their eggs from the Aleutians: arsenic, cadmium, chromium, lead, manganese, mercury, and selenium

    PubMed Central

    Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Snigaroff, Daniel; Snigaroff, Ronald; Stamm, Timothy; Volz, Conrad

    2014-01-01

    Concentrations of arsenic, cadmium, chromium, lead, manganese, mercury and selenium were examined in the down feathers and eggs of female common eiders (Somateria mollissima) from Amchitka and Kiska Islands in the Aleutian Chain of Alaska to determine whether there were (1) differences between levels in feathers and eggs, (2) differences between the two islands, (3) positive correlations between metal levels in females and their eggs, and (4) whether there was more variation within or among clutches. Mean levels in eggs (dry weight) were as follows: arsenic (769 ppb, ng/g), cadmium (1.49 ppb), chromium (414 ppb), lead (306 ppb), manganese (1,470 ppb), mercury (431 ppb) and selenium (1,730 ppb). Levels of arsenic were higher in eggs, while chromium, lead, manganese, and mercury were higher in feathers; there were no differences for selenium. There were no significant interisland differences in female feather levels, except for manganese (eider feathers from Amchitka were four times higher than feathers from Kiska). Levels of manganese in eggs were also higher from Amchitka than Kiska, and eider eggs from Kiska had significantly higher levels of arsenic, but lower levels of selenium. There were no significant correlations between the levels of any metals in down feathers of females and in their eggs. The levels of mercury in eggs were below ecological benchmark levels, and were below human health risk levels. However, Aleuts can seasonally consume several meals of bird eggs a week, suggesting cause for concern for sensitive (pregnant) women. PMID:17934788

  4. Magnetic properties of alluvial soils contaminated with lead, zinc and cadmium

    NASA Astrophysics Data System (ADS)

    Petrovský, E.; Kapička, A.; Jordanova, N.; Borůvka, L.

    2001-09-01

    Several proxy methods have been used recently to outline increased levels of pollution. One of them is based on measurements of the concentration of (ferri)magnetic minerals of anthropogenic origin. This method has been used recently in the mapping of both polluted and unpolluted areas. In order to validate this method, a more detailed study of links between magnetic parameters characterising the physical shape of magnetic minerals and concentrations of heavy metals is needed. In this study, we analysed the magnetic characteristics of alluvial soils, formed as a result of several breakdowns of wet deposit sink of ashes from a lead ore smelter. The soils were previously analysed for concentration of lead, zinc and cadmium. Our results show that in this case of a shared source of heavy metals and magnetic minerals, simple measurements of magnetic susceptibility discriminate well between polluted and clean areas. In addition, the concentration pattern agrees with the concentrations of the heavy metals studied in deeper soil layers that were not affected by post-depositional changes due to climate and remediation efforts.

  5. What Do We Know of Childhood Exposures to Metals (Arsenic, Cadmium, Lead, and Mercury) in Emerging Market Countries?

    PubMed Central

    Horton, Lindsey M.; Mortensen, Mary E.; Iossifova, Yulia; Wald, Marlena M.; Burgess, Paula

    2013-01-01

    Arsenic, cadmium, lead, and mercury present potential health risks to children who are exposed through inhalation or ingestion. Emerging Market countries experience rapid industrial development that may coincide with the increased release of these metals into the environment. A literature review was conducted for English language articles from the 21st century on pediatric exposures to arsenic, cadmium, lead, and mercury in the International Monetary Fund's (IMF) top 10 Emerging Market countries: Brazil, China, India, Indonesia, Mexico, Poland, Russia, South Korea, Taiwan, and Turkey. Seventy-six peer-reviewed, published studies on pediatric exposure to metals met the inclusion criteria. The reported concentrations of metals in blood and urine from these studies were generally higher than US reference values, and many studies identified adverse health effects associated with metals exposure. Evidence of exposure to metals in the pediatric population of these Emerging Market countries demonstrates a need for interventions to reduce exposure and efforts to establish country-specific reference values through surveillance or biomonitoring. The findings from review of these 10 countries also suggest the need for country-specific public health policies and clinician education in Emerging Markets. PMID:23365584

  6. What do we know of childhood exposures to metals (arsenic, cadmium, lead, and mercury) in emerging market countries?

    PubMed

    Horton, Lindsey M; Mortensen, Mary E; Iossifova, Yulia; Wald, Marlena M; Burgess, Paula

    2013-01-01

    Arsenic, cadmium, lead, and mercury present potential health risks to children who are exposed through inhalation or ingestion. Emerging Market countries experience rapid industrial development that may coincide with the increased release of these metals into the environment. A literature review was conducted for English language articles from the 21st century on pediatric exposures to arsenic, cadmium, lead, and mercury in the International Monetary Fund's (IMF) top 10 Emerging Market countries: Brazil, China, India, Indonesia, Mexico, Poland, Russia, South Korea, Taiwan, and Turkey. Seventy-six peer-reviewed, published studies on pediatric exposure to metals met the inclusion criteria. The reported concentrations of metals in blood and urine from these studies were generally higher than US reference values, and many studies identified adverse health effects associated with metals exposure. Evidence of exposure to metals in the pediatric population of these Emerging Market countries demonstrates a need for interventions to reduce exposure and efforts to establish country-specific reference values through surveillance or biomonitoring. The findings from review of these 10 countries also suggest the need for country-specific public health policies and clinician education in Emerging Markets.

  7. Mercury

    NASA Technical Reports Server (NTRS)

    Vilas, Faith (Editor); Chapman, Clark R. (Editor); Matthews, Mildred Shapley (Editor)

    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.

  8. 40 CFR 440.100 - Applicability; description of the copper, lead, zinc, gold, silver, and molybdenum ores subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... process alone or in conjunction with other processes, for the beneficiation of copper, lead, zinc, gold, silver, or molybdenum ores, or any combination of these ores; (3) Mines and mills that use dump, heap, in-situ leach, or vat-leach processes to extract copper from ores or ore waste materials; and (4) Mills...

  9. 40 CFR 440.100 - Applicability; description of the copper, lead, zinc, gold, silver, and molybdenum ores subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... process alone or in conjunction with other processes, for the beneficiation of copper, lead, zinc, gold, silver, or molybdenum ores, or any combination of these ores; (3) Mines and mills that use dump, heap, in-situ leach, or vat-leach processes to extract copper from ores or ore waste materials; and (4) Mills...

  10. 40 CFR 440.100 - Applicability; description of the copper, lead, zinc, gold, silver, and molybdenum ores subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... process alone or in conjunction with other processes, for the beneficiation of copper, lead, zinc, gold, silver, or molybdenum ores, or any combination of these ores; (3) Mines and mills that use dump, heap, in-situ leach, or vat-leach processes to extract copper from ores or ore waste materials; and (4) Mills...

  11. The mechanisms associated with the development of hypertension after exposure to lead, mercury species or their mixtures differs with the metal and the mixture ratio.

    PubMed

    Wildemann, Tanja M; Siciliano, Steven D; Weber, Lynn P

    2016-01-02

    Hypertension is considered to be the most important risk factor for the development of cardiovascular diseases. Beside life-style risk factors, exposure to lead and mercury species are increasingly discussed as potential risk factors. Although there are a few previous studies, the underlying mechanism by which exposure to lead and mercury disturb blood pressure regulation is not currently understood. Potential mechanisms are oxidative stress production, kidney damage and activation of the renin-angiotensin system (RAS), all of which can interact to cause dysregulation of blood pressure. Male rats (Wistar) were exposed to lead, inorganic mercury, methylmercury or two mixtures of all three metals for four weeks through the drinking water. The two mixture ratios were based on ratios of known reference values or environmental exposure from the literature. To investigate the potential mechanism of actions, blood pressure was measured after four weeks and compared to plasma nitrotyrosine or reduced/oxidized glutathione levels in liver as markers for oxidative stress. Plasma renin and angiotensin II levels were used as markers for RAS activation. Finally, kidney function and injury were assessed via urinary and plasma creatinine levels, creatinine clearance and urinary kidney-injury molecule (KIM-1). While exposure to lead by itself increased oxidative stress and kidney damage along with blood pressure, inorganic mercury did not affect blood pressure or any end-point examined. Conversely, methylmercury instead increased RAS activation along with blood pressure. Surprisingly, when administered as mixtures, lead no longer increased oxidative stress or altered kidney function. Moreover, the mixture based on an environmental ratio no longer had an effect on blood pressure, while the reference value ratio still retained an increase in blood pressure. Based on our results, the prominent mechanism of action associated with the development of hypertension seems to be oxidative

  12. Endoscopic management of massive mercury ingestion

    PubMed Central

    Zag, Levente; Berkes, Gábor; Takács, Irma F; Szepes, Attila; Szabó, István

    2017-01-01

    Abstract Rationale: Ingestion of a massive amount of metallic mercury was thought to be harmless until the last century. After that, in a number of cases, mercury ingestion has been associated with appendicitis, impaired liver function, memory deficits, aspiration leading to pneumonitis and acute renal failure. Treatment includes gastric lavage, giving laxatives and chelating agents, but rapid removal of metallic mercury with gastroscopy has not been used. Patient concerns: An 18-year-old man was admitted to our emergency department after drinking 1000 g of metallic mercury as a suicide attempt. Diagnosis: Except from mild umbilical tenderness, he had no other symptoms. Radiography showed a metallic density in the area of the stomach. Intervention: Gastroscopy was performed to remove the mercury. One large pool and several small droplets of mercury were removed from the stomach. Outcomes: Blood and urine mercury levels of the patient remained low during hospitalization. No symptoms of mercury intoxication developed during the follow-up period. Lessons: Massive mercury ingestion may cause several symptoms, which can be prevented with prompt treatment. We used endoscopy to remove the mercury, which shortened the exposure time and minimized the risk of aspiration. This is the first case where endoscopy was used for the management of mercury ingestion. PMID:28562544

  13. Determination of silver, bismuth, cadmium, copper, lead, and zinc in geologic materials by atomic absorption spectrometry with tricaprylylmethylammonium chloride

    USGS Publications Warehouse

    Viets, J.G.

    1978-01-01

    Interferences commonly encountered in the determination of silver, bismuth, cadmium, copper, lead, and zinc at crustal abundance levels are effectively eliminated using a rapid, sensitive, organic extraction technique. A potassium chlorate-hydrochloric acid digestion solubilizes the metals not tightly bound in the silicate lattice of rocks, soils, and stream sediments. The six metals are selectively extracted into a 10% Aliquat 336-MIBK organic phase in the presence of ascorbic acid and potassium iodide. Metals in the organic extract are determined by flame atomic absorption spectrometry to the 0.02-ppm level for silver, cadmium, copper, and zinc and to the 0.2-ppm level for bismuth and lead with a maximum relative standard deviation of 18.8% for known reference samples. An additional hydrofluoric acid digestion may be used to determine metals substituted in the silicate lattice.

  14. Mercury in dental amalgam: Are our health care workers at risk?

    PubMed

    Sahani, M; Sulaiman, N S; Tan, B S; Yahya, N A; Anual, Z F; Mahiyuddin, W R Wan; Khan, M F; Muttalib, K A

    2016-11-01

    Dental amalgam in fillings exposes workers to mercury. The exposure to mercury was investigated among 1871 dental health care workers. The aim of the study was to evaluate the risk of mercury exposure among dental compared to nondental health care workers and to determine other risk factors for mercury exposure. Respondents answered questionnaires to obtain demographic, personal, professional, and workplace information and were examined for their own amalgam fillings. Chronic mercury exposure was assessed through urinary mercury levels. In total, 1409 dental and 462 nondental health care workers participated in the study. Median urine mercury levels for dental and nondental health care workers were 2.75 μg/L (interquartile range [IQR] = 3.0175) and 2.66 μg/L (IQR = 3.04) respectively. For mercury exposure, there were no significant risk factor found among the workers involved within the dental care. The Mann-Whitney test showed that urine mercury levels were significantly different between respondents who eat seafood more than 5 times per week compared to those who eat it less frequently or not at all (p = 0.003). The urinary mercury levels indicated significant difference between dental workers in their practice using squeeze cloths (Mann-Whitney test, p = 0.03). Multiple logistic regression showed that only the usage of cosmetic products that might contain mercury was found to be significantly associated with the urinary mercury levels (odds ratio [OR] = 15.237; CI: 3.612-64.276). Therefore, mean urinary mercury levels of health care workers were low. Exposure to dental amalgam is not associated with high mercury exposure. However, usage of cosmetic products containing mercury and high seafood consumption may lead to the increase of exposure to mercury. Exposure to the high levels of mercury from dental amalgam can lead to serious health effects among the dental health care workers. Nationwide chronic mercury exposure among dental personnel was assessed through

  15. Arsenic, cadmium, chromium, lead, manganese, mercury, and selenium in feathers of Black-legged Kittiwake (Rissa tridactyla) and Black Oystercatcher (Haematopus bachmani) from Prince William Sound, Alaska

    PubMed Central

    Burger, Joanna; Gochfeld, Michael; Sullivan, Kelsey; Irons, David; McKnight, Aly

    2014-01-01

    Arsenic, cadmium, chromium, lead, manganese, mercury and selenium were analyzed in the feathers of Black-legged Kittiwakes (Rissa tridactyla) from Shoup Bay in Prince William Sound, Alaska to determine if there were age-related differences in metal levels, and in Black Oystercatchers (Haematopus bachmani)) from the same region to determine if there were differences in oiled and unoiled birds. Except for mercury, there were no age-related differences in metals levels in the feathers of kittiwakes. Kittiwakes over 13 years of age had the highest levels of mercury. There were no differences in levels of metals in the feathers of oystercatchers from oiled and unoiled regions of Prince William Sound. Except for mercury, the feathers of oystercatchers had significantly higher levels of all metals than those of kittiwakes. Levels of mercury in kittiwake feathers (mean of 2910 ng/g [ppb]) were within the range of many species of seabirds reported for other studies, and were generally below adverse effects levels. PMID:18440597

  16. Cadmium, mercury, and lead in kidney cortex of living kidney donors: Impact of different exposure sources,

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barregard, Lars, E-mail: lars.barregard@amm.gu.se; Fabricius-Lagging, Elisabeth; Lundh, Thomas

    Background: Most current knowledge on kidney concentrations of nephrotoxic metals like cadmium (Cd), mercury (Hg), or lead (Pb) comes from autopsy studies. Assessment of metal concentrations in kidney biopsies from living subjects can be combined with information about exposure sources like smoking, diet, and occupation supplied by the biopsied subjects themselves. Objectives: To determine kidney concentrations of Cd, Hg, and Pb in living kidney donors, and assess associations with common exposure sources and background factors. Methods: Metal concentrations were determined in 109 living kidney donors aged 24-70 years (median 51), using inductively coupled plasma-mass spectrometry (Cd and Pb) and coldmore » vapor atomic fluorescence spectrometry (Hg). Smoking habits, occupation, dental amalgam, fish consumption, and iron stores were evaluated. Results: The median kidney concentrations were 12.9 {mu}g/g (wet weight) for cadmium, 0.21 {mu}g/g for mercury, and 0.08 {mu}g/g for lead. Kidney Cd increased by 3.9 {mu}g/g for a 10 year increase in age, and by 3.7 {mu}g/g for an extra 10 pack-years of smoking. Levels in non-smokers were similar to those found in the 1970s. Low iron stores (low serum ferritin) in women increased kidney Cd by 4.5 {mu}g/g. Kidney Hg increased by 6% for every additional amalgam surface, but was not associated with fish consumption. Lead was unaffected by the background factors surveyed. Conclusions: In Sweden, kidney Cd levels have decreased due to less smoking, while the impact of diet seems unchanged. Dental amalgam is the main determinant of kidney Hg. Kidney Pb levels are very low due to decreased exposure.« less

  17. Simultaneous Automatic Electrochemical Detection of Zinc, Cadmium, Copper and Lead Ions in Environmental Samples Using a Thin-Film Mercury Electrode and an Artificial Neural Network

    PubMed Central

    Kudr, Jiri; Nguyen, Hoai Viet; Gumulec, Jaromir; Nejdl, Lukas; Blazkova, Iva; Ruttkay-Nedecky, Branislav; Hynek, David; Kynicky, Jindrich; Adam, Vojtech; Kizek, Rene

    2015-01-01

    In this study a device for automatic electrochemical analysis was designed. A three electrodes detection system was attached to a positioning device, which enabled us to move the electrode system from one well to another of a microtitre plate. Disposable carbon tip electrodes were used for Cd(II), Cu(II) and Pb(II) ion quantification, while Zn(II) did not give signal in this electrode configuration. In order to detect all mentioned heavy metals simultaneously, thin-film mercury electrodes (TFME) were fabricated by electrodeposition of mercury on the surface of carbon tips. In comparison with bare electrodes the TMFEs had lower detection limits and better sensitivity. In addition to pure aqueous heavy metal solutions, the assay was also performed on mineralized rock samples, artificial blood plasma samples and samples of chicken embryo organs treated with cadmium. An artificial neural network was created to evaluate the concentrations of the mentioned heavy metals correctly in mixture samples and an excellent fit was observed (R2 = 0.9933). PMID:25558996

  18. Transformations of Heavy Metals and Plant Nutrients in Dredged Sediments as Affected by Oxidation Reduction Potential and pH. Volume 1. Literature Review

    DTIC Science & Technology

    1977-05-01

    895-896 (1974). 191. Fagerstrom, T., and Jernelov, A. "Formation of Methyl Mercury from Pure Mercuric Sulphide in Aerobic Organic Sediment." Water...was available. The toxic and nutrient elements included are lead, cadmium, mercury , arsenic, selenium, copper, zinc, manganese, iron, nitrogen...on the exchange of these materials between sediment and water. The toxic and nutrient elements included are lead, cadmium, mercury , ar- senic

  19. Mercury and halogens in coal--Their role in determining mercury emissions from coal combustion

    USGS Publications Warehouse

    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

  20. Metal chelators and neurotoxicity: lead, mercury, and arsenic.

    PubMed

    Bjørklund, Geir; Mutter, Joachim; Aaseth, Jan

    2017-12-01

    This article reviews the clinical use of the metal chelators sodium 2,3-dimercapto-1-propanesulfonate (DMPS), meso-2,3-dimercaptosuccinic acid (DMSA), and calcium disodium edetate (CaEDTA, calcium EDTA) in overexposure and poisonings with salts of lead (Pb), mercury (Hg), and arsenic (As). DMSA has considerably lower toxicity than the classic heavy metal antagonist BAL (2,3-dimercaptopropanol) and is also less toxic than DMPS. Because of its adverse effects, CaEDTA should be replaced by DMSA as the antidote of choice in treating moderate Pb poisoning. Combination therapy with BAL and CaEDTA was previously recommended in cases of severe acute Pb poisoning with encephalopathy. We suggest that BAL in such cases acted as a shuttling Pb transporter from the intra- to the extracellular space. The present paper discusses if a combination of the extracellularly distributed DMSA with the ionophore, Monensin may provide a less toxic combination for Pb mobilization by increasing both the efflux of intracellularly deposited Pb and the urinary Pb excretion. Anyhow, oral therapy with DMSA should be continued with several intermittent courses. DMPS and DMSA are also promising antidotes in Hg poisoning, whereas DMPS seems to be a more efficient agent against As poisoning. However, new insight indicates that a combination of low-dosed BAL plus DMPS could be a preferred antidotal therapy to obtain mobilization of the intracerebral deposits into the circulation for subsequent rapid urinary excretion.

  1. Toward a Unified Understanding of Mercury and Methylated Mercury from the World's Oceans

    NASA Astrophysics Data System (ADS)

    McNutt, M. K.; Krabbenhoft, D. P.; Landing, W. M.; Sunderland, E. M.

    2012-12-01

    -profile concentration maxima, however, the depth of the maxima are more varied than the total mercury profiles (150 - 700m). Also, our observed distribution of methylated mercury highly correlated with organic carbon remineralization rates (OCRR) in the North Pacific and Indian Oceans. Interestingly, we find the highest methylated mercury concentrations in the Southern Ocean, suggesting the possibility of unique mechanisms for methylmercury production, preservation, and degradation in polar ecosystems such as cold water temperatures, extended periods of sea ice cover, and annual atmospheric mercury depletion events. We are using these data to better link oceanic production of bioaccumulative mercury to models for atmospheric and oceanic transport and bioaccumulation. This will ultimately lead to a better understanding of mercury levels in consumable fish and shell fish.

  2. Aerospect operations criteria for Mercury thresholds

    NASA Technical Reports Server (NTRS)

    Katz, S.

    1979-01-01

    The hazards anticipated from a large scale mercury spill during a possible failure in the preflight and early flight stages of the Space Shuttle were studied. Toxicity thresholds were investigated as well as other consequences of mercury interacting with the environment. Three sites of mercury spill were investigated: land, water, and atmosphere. A laboratory study of interactions between mercury vapor and ozone in a low pressure, high ultraviolet radiation environment approximated the conditions of a mercury vapor release in the ozone layer region of the stratosphere. Clear evidence of an interaction leading to the destruction of ozone by conversion to oxygen was obtained. The impact of a spill on the Earth's environment and methods of early detection of a developing hazard wave of primary concern in the study.

  3. Compilation of Mineral Resource Data for Mississippi Valley-Type and Clastic-Dominated Sediment-Hosted Lead-Zinc Deposits

    USGS Publications Warehouse

    Taylor, Ryan D.; Leach, David L.; Bradley, Dwight C.; Pisarevsky, Sergei A.

    2009-01-01

    This report contains a global compilation of the mineral resource data for sediment-hosted lead-zinc (SH Pb-Zn) deposits. Sediment-hosted lead-zinc deposits are historically the most significant sources of lead and zinc, and are mined throughout the world. The most important SH Pb-Zn deposits are hosted in clastic-dominated sedimentary rock sequences (CD Pb-Zn) that are traditionally called sedimentary exhalative (SEDEX) deposits, and those in carbonate-dominated sequences that are known as Mississippi Valley-type (MVT) Pb-Zn deposits. In this report, we do not include sandstone-Pb, sandstone-hosted Pb, or Pb-Zn vein districts such as those in Freiberg, Germany, or Coeur d'Alene, Idaho, because these deposits probably represent different deposit types (Leach and others, 2005). We do not include fracture-controlled deposits in which fluorite is dominant and barite typically abundant (for example, Central Kentucky; Hansonburg, N. Mex.) or the stratabound fluorite-rich, but also lead- and zinc-bearing deposits, such as those in southern Illinois, which are considered a genetic variant of carbonate-hosted Pb-Zn deposits (Leach and Sangster, 1993). This report updates the Pb, Zn, copper (Cu), and silver (Ag) grade and tonnage data in Leach and others (2005), which itself was based on efforts in the Canadian Geological Survey World Minerals Geoscience Database Project (contributions of D.F. Sangster to Sinclair and others, 1999). New geological or geochronological data, classifications of the tectonic environment in which the deposits formed, and key references to the geology of the deposits are presented in our report. Data for 121 CD deposits, 113 MVT deposits, and 6 unclassified deposits that were previously classified as either SEDEX or MVT in the Leach and others (2005) compilation, are given in appendix table A1. In some cases, mineral resource data were available only for total district resources, but not for individual mines within the district. For these

  4. Bioleaching combined brine leaching of heavy metals from lead-zinc mine tailings: Transformations during the leaching process.

    PubMed

    Ye, Maoyou; Yan, Pingfang; Sun, Shuiyu; Han, Dajian; Xiao, Xiao; Zheng, Li; Huang, Shaosong; Chen, Yun; Zhuang, Shengwei

    2017-02-01

    During the process of bioleaching, lead (Pb) recovery is low. This low recovery is caused by a problem with the bioleaching technique. This research investigated the bioleaching combination of bioleaching with brine leaching to remove heavy metals from lead-zinc mine tailings. The impact of different parameters were studied, including the effects of initial pH (1.5-3.0) and solid concentration (5-20%) for bioleaching, and the effects of sodium chloride (NaCl) concentration (10-200 g/L) and temperature (25 and 50 °C) for brine leaching. Complementary characterization experiments (Sequential extraction, X-ray diffractometer (XRD), scanning electronic microscope (SEM)) were also conducted to explore the transformation of tailings during the leaching process. The results showed that bioleaching efficiency was significantly influenced by initial pH and solid concentration. Approximately 85.45% of iron (Fe), 4.12% of Pb, and 97.85% of zinc (Zn) were recovered through bioleaching in optimum conditions. Increasing the brine concentration and temperature promoted lead recovery. Lead was recovered from the bioleaching residues at a rate of 94.70% at 25 °C and at a rate of 99.46% at 50 °C when the NaCl concentration was 150 g/L. The study showed that bioleaching significantly changed the speciation of heavy metals and the formation and surface morphology of tailings. The metals were mainly bound in stable fractions after bioleaching. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Association of Dietary Intake and Biomarker Levels of Arsenic, Cadmium, Lead, and Mercury among Asian Populations in the United States: NHANES 2011-2012.

    PubMed

    Awata, Hiroshi; Linder, Stephen; Mitchell, Laura E; Delclos, George L

    2017-03-01

    We have recently shown that biomarker levels of selected metals are higher in Asians than in other U.S. ethnic groups, with important differences within selected Asian subgroups. Much of this difference may be dietary in origin; however, this is not well established. We evaluated dietary intake of toxic metals as a source of increased biomarker levels of metals among U.S. Asians. We estimated daily food consumption and dietary intake of arsenic, cadmium, lead, and mercury by combining 24-hr dietary intake recall data from the 2011-2012 National Health and Nutrition Examination Survey (NHANES) with data from the USDA Food Composition Intake Database and FDA Total Dietary Study. We analyzed associations between dietary metal intake and biomarker levels of the metals using linear regression. Further, estimated food consumption and metal intake levels were compared between Asians and other racial/ethnic groups (white, black, Mexican American, and other Hispanic) and within three Asian subgroups (Chinese, Indian Asian, and other Asians). Significant associations ( p < 0.05) were found between biomarker levels and estimated dietary metal intake for total and inorganic arsenic and mercury among Asians. Asians had the highest daily fish and rice consumption across the racial/ethnic groups. Fish was the major contributor to dietary mercury and total arsenic intake, whereas rice was the major contributor to inorganic arsenic dietary intake. Fish consumption across the Asian subgroups varied, with Asian Indians having lower fish consumption than the other Asian subgroups. Rice consumption was similar across the Asian subgroups. We confirmed that estimated dietary intake of arsenic (total and inorganic) and mercury is significantly associated with their corresponding biomarkers in U.S. Asians, using nationally representative data. In contrast, estimated dietary intake of cadmium and lead were not significantly associated with their corresponding biomarker levels in U.S. Asians

  6. Isotope effect of mercury diffusion in air

    PubMed Central

    Koster van Groos, Paul G.; Esser, Bradley K.; Williams, Ross W.; Hunt, James R.

    2014-01-01

    Identifying and reducing impacts from mercury sources in the environment remains a considerable challenge and requires process based models to quantify mercury stocks and flows. The stable isotope composition of mercury in environmental samples can help address this challenge by serving as a tracer of specific sources and processes. Mercury isotope variations are small and result only from isotope fractionation during transport, equilibrium, and transformation processes. Because these processes occur in both industrial and environmental settings, knowledge of their associated isotope effects is required to interpret mercury isotope data. To improve the mechanistic modeling of mercury isotope effects during gas phase diffusion, an experimental program tested the applicability of kinetic gas theory. Gas-phase elemental mercury diffusion through small bore needles from finite sources demonstrated mass dependent diffusivities leading to isotope fractionation described by a Rayleigh distillation model. The measured relative atomic diffusivities among mercury isotopes in air are large and in agreement with kinetic gas theory. Mercury diffusion in air offers a reasonable explanation of recent field results reported in the literature. PMID:24364380

  7. Isotope effect of mercury diffusion in air.

    PubMed

    Koster van Groos, Paul G; Esser, Bradley K; Williams, Ross W; Hunt, James R

    2014-01-01

    Identifying and reducing impacts from mercury sources in the environment remains a considerable challenge and requires process based models to quantify mercury stocks and flows. The stable isotope composition of mercury in environmental samples can help address this challenge by serving as a tracer of specific sources and processes. Mercury isotope variations are small and result only from isotope fractionation during transport, equilibrium, and transformation processes. Because these processes occur in both industrial and environmental settings, knowledge of their associated isotope effects is required to interpret mercury isotope data. To improve the mechanistic modeling of mercury isotope effects during gas phase diffusion, an experimental program tested the applicability of kinetic gas theory. Gas-phase elemental mercury diffusion through small bore needles from finite sources demonstrated mass dependent diffusivities leading to isotope fractionation described by a Rayleigh distillation model. The measured relative atomic diffusivities among mercury isotopes in air are large and in agreement with kinetic gas theory. Mercury diffusion in air offers a reasonable explanation of recent field results reported in the literature.

  8. Application of Polypyrrole Multi-Walled Carbon Nanotube Composite Layer for Detection of Mercury, Lead and Iron Ions Using Surface Plasmon Resonance Technique

    PubMed Central

    Sadrolhosseini, Amir Reza; Noor, A. S. M.; Bahrami, Afarin; Lim, H. N.; Talib, Zainal Abidin; Mahdi, Mohd. Adzir

    2014-01-01

    Polypyrrole multi-walled carbon nanotube composite layers were used to modify the gold layer to measure heavy metal ions using the surface plasmon resonance technique. The new sensor was fabricated to detect trace amounts of mercury (Hg), lead (Pb), and iron (Fe) ions. In the present research, the sensitivity of a polypyrrole multi-walled carbon nanotube composite layer and a polypyrrole layer were compared. The application of polypyrrole multi-walled carbon nanotubes enhanced the sensitivity and accuracy of the sensor for detecting ions in an aqueous solution due to the binding of mercury, lead, and iron ions to the sensing layer. The Hg ion bonded to the sensing layer more strongly than did the Pb and Fe ions. The limitation of the sensor was calculated to be about 0.1 ppm, which produced an angle shift in the region of 0.3° to 0.6°. PMID:24733263

  9. 40 CFR 503.13 - Pollutant limits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... kilogram) 1 Arsenic 75 Cadmium 85 Copper 4300 Lead 840 Mercury 57 Molybdenum 75 Nickel 420 Selenium 100... Pollutant Loading Rates Pollutant Cumulative pollutant loading rate (kilograms per hectare) Arsenic 41... kilogram) 1 Arsenic 41 Cadmium 39 Copper 1500 Lead 300 Mercury 17 Nickel 420 Selenium 100 Zinc 2800 1 Dry...

  10. 40 CFR 503.13 - Pollutant limits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... kilogram) 1 Arsenic 75 Cadmium 85 Copper 4300 Lead 840 Mercury 57 Molybdenum 75 Nickel 420 Selenium 100... Pollutant Loading Rates Pollutant Cumulative pollutant loading rate (kilograms per hectare) Arsenic 41... kilogram) 1 Arsenic 41 Cadmium 39 Copper 1500 Lead 300 Mercury 17 Nickel 420 Selenium 100 Zinc 2800 1 Dry...

  11. Concentrations of selenium, mercury, and lead in blood of emperor geese in western Alaska

    USGS Publications Warehouse

    Franson, J.C.; Schmutz, J.A.; Creekmore, L.H.; Fowler, A.C.

    1999-01-01

    We found up to 10 ppm wet weight of selenium in blood samples collected from emperor geese (Chen canagica) on their breeding grounds on the Yukon‐Kuskokwim Delta in western Alaska, USA. Incubating adult females captured in late May through mid‐June 1997 had significantly higher concentrations of selenium in their blood (mean = 5.60 ppm) than adult females captured during wing molt in late July 1996 (mean = 2.78 ppm). Females that nested early or were in good body condition had higher concentrations of selenium in their blood than did other nesting females. Blood samples from 4 of 29 goslings had detectable levels of selenium (mean = 0.14 ppm). Our findings suggest that emperor geese are exposed to more selenium in the marine environment of their wintering and staging areas on the Alaska Peninsula than on the breeding grounds. The highest concentration of mercury found in the blood of emperor geese was 0.24 ppm. One bird had a blood lead concentration of 0.67 ppm, but 82% had no detectable lead in their blood, suggesting that lead exposure from the ingestion of lead shot poses little threat for emperor geese in western Alaska, contrary to findings reported for sympatric spectacled eiders (Somateria fischeri).

  12. Effects of cell condition, pH, and temperature on lead, zinc, and copper sorption to Acidithiobacillus caldus strain BC13

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    John E. Aston; William A. Apel; Brady D. Lee

    2010-12-01

    This study describes the effects of cell condition, pH, and temperature on lead, zinc, and copper sorption to Acidithiobacillus caldus strain BC13 with a Langmuir model. Copper exhibited the highest loading capacity, 4.76 ± 0.28 mmol g-1, to viable cells at pH 5.5. The highest kL (binding-site affinity) observed was 61.2 ± 3.0 L mmol-1 to dehydrated cells at pH 4.0. The pHs that maximized loading capacities and binding-site affinities were generally between 4.0 and 5.5, where the sum of free-proton and complexed-metal concentrations was near a minimum. Of additional importance, lead, zinc, and copper sorbed to viable cells atmore » pH values as low as 1.5. Previous studies with other acidithiobacilli did not measure viable-cell sorption below pH 4.0. In separate experiments, desorption studies showed that far less copper was recovered from viable cells than any other metal or cell condition, suggesting that uptake may play an important role in copper sorption by At. caldus strain BC13. To reflect an applied system, the sorption of metal mixtures was also studied. In these experiments, lead, zinc, and copper sorption from a tertiary mixture were 40.2 ± 4.3%, 28.7 ± 3.8%, and 91.3 ± 3.0%, respectively, of that sorbed in single-metal systems.« less

  13. Modeling Mercury

    NASA Astrophysics Data System (ADS)

    Burger, M. H.; Killen, R. M.; M, N.; Sarantos, M.; Crider, D. H.; Vervak, R. J.

    2009-04-01

    redistributing volatiles over the surface. In addition, atomic calcium can be produced from the dissociation of Ca-bearing molecules, such as CaO, which can be formed in impact vapors. The primary loss processes are the escape of neutrals ejected with sufficient energy and photoionization. The former process is supplemented by radiation pressure which accelerates neutrals anti-sunward such that escaping neutrals form a tail pointing away from the sun. Because Mercury's heliocentric distance and radial velocity vary during its orbit, both loss processes are functions of Mercury's true anomaly. We also consider the spatial distribution of the surface source. Impact vaporization is roughly isotropic over the surface, although there may be a leading/trailing asymmetry in the impact rate due to Mercury's orbital motion. Sputtering is confined to regions where the solar wind can impact the surface, which is shielded somewhat by the internal magnetic field. The surface regions vulnerable depend on the solar wind conditions. References: Baumgardner et al., GRL, 35, L03201, 2008. Killen, R.M. et al., Space Sci. Rev. 132, 433-509, 2007. Killen, R.M. et al., Icarus, 173, 300-311, 2005. Potter et al., Meteoritics & Planetary Sci., 37, 1165, 2002.

  14. [Mercury (and...) through the centuries].

    PubMed

    Kłys, Małgorzata

    2010-01-01

    Mercury has a long history, fascinating in its many aspects. Through the centuries--from ancient times to the present day--the metal in its various forms, also known under the name "quicksilver", accompanied the man and was used for diversified purposes. Today, mercury is employed in manufacturing thermometers, barometers, vacuum pumps and explosives. It is also used in silver and gold mining processes. Mercury compounds play a significant role in dentistry, pharmaceutical industry and crop protection. The contemporary use of mercury markedly decreases, but historically speaking, the archives abound in materials that document facts and events occurring over generations and the immense intellectual effort aiming at discovering the true properties and mechanisms of mercury activity. Mercury toxicity, manifested in destruction of biological membranes and binding of the element with proteins, what disturbs biochemical processes occurring in the body, was discovered only after many centuries of the metal exerting its effect on the lives of individuals and communities. For centuries, mercury was present in the work of alchemists, who searched for the universal essence or quintessence and the so-called philosopher's stone. In the early modern era, between the 16th and 19th centuries, mercury was used to manufacture mirrors. Mercury compounds were employed as a medication against syphilis, which plagued mankind for more than four hundred years--from the Middle Ages till mid 20th century, when the discovery of penicillin became the turning point. This extremely toxic therapy resulted in much suffering, individual tragedies, chronic poisonings leading to fatalities and dramatic sudden deaths. In the last fifty years, there even occurred attempts of mentally imbalanced individuals at injecting themselves with metallic mercury, also as a performance-enhancing drug. Instances of mass mercury poisoning occurred many times in the past in consequence of eating food products

  15. Influence of farmyard manure on retention and availability of nickel, zinc and lead in metal-contaminated calcareous loam soils

    USDA-ARS?s Scientific Manuscript database

    Continuous irrigation of crops with untreated municipal effluent can result in the accumulation of nickel (Ni), zinc (Zn), and lead (Pb) in soils and translocation to the plants. Application of farm yard manure (FYM) to metal-contaminated soils may increase or decrease the availability and retention...

  16. Effects of sublethal exposure to zinc chloride on the reproduction of the water flea, Moina irrasa (cladocera)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zou, E.

    1997-03-01

    As a result of industrial activities, aquatic ecosystems have been contaminated increasingly by metals. Such occurrences pose a threat to aquatic organisms in particular and to the whole ecosystem in general. Because of their importance as part of the food chains in the freshwater ecosystem, as well as their high vulnerability to metal contaminants, the cladoceran crustaceans have attracted attention by toxicologists. The acute toxicity of metals to cladocerans has been well documented by. However, most of the investigations in chronic toxicity deal with metals not essential for life such as mercury and cadmium. It is well known that exposuremore » to mercury and cadmium can generally render inhibitory effects. However, the effects of sublethal exposure of cladocerans to metals such as zinc and selenium, which are essential for life at trace level, are not as well known. As one of the major metal contaminants in freshwater ecosystems, zinc is of ecotoxicological interest. The effects of sublethal zinc exposure, especially at low concentrations, on the reproduction of cladocerans are poorly understood. The objective of this study was to investigate the effects of exposure to a wide range of sublethal concentrations of zinc chloride on the reproduction of Moina irrasa, a cladoceran commonly found in the freshwaters of the Yangtze delta of China. 11 refs., 1 tab.« less

  17. Reference Atmosphere for Mercury

    NASA Technical Reports Server (NTRS)

    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.

  18. Terminator View of Mercury

    NASA Image and Video Library

    2014-07-02

    Date acquired: May 05, 2014 Today's color image features both Mercury's terminator and limb. The terminator is the striking separation of night and day on Mercury. It is seen in this image with the change from dark, on the left of the image, to light. Mercury's limb is also captured, as we can see the edge between sunlit Mercury and space. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. During the first two years of orbital operations, MESSENGER acquired over 150,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  19. A screening-level assessment of lead, cadmium, and zinc in fish and crayfish from northeastern Oklahoma, USA

    USGS Publications Warehouse

    Schmitt, C.J.; Brumbaugh, W.G.; Linder, G.L.; Hinck, J.E.

    2006-01-01

    The objective of this study was to evaluate potential human and ecological risks associated with metals in fish and crayfish from mining in the Tri-States Mining District (TSMD). Crayfish (Orconectes spp.) and fish of six frequently consumed species (common carp, Cyprinus carpio; channel catfish, Ictalurus punctatus; flathead catfish, Pylodictis olivaris; largemouth bass, Micropterus salmoides; spotted bass, M. punctulatus; and white crappie, Pomoxis annularis) were collected in 2001-2002 from the Oklahoma waters of the Spring River (SR) and Neosho River (NR), which drain the TSMD. Samples from a mining-contaminated site in eastern Missouri and from reference sites were also analyzed. Individual fish were prepared for human consumption in the manner used locally by Native Americans (headed, eviscerated, and scaled) and analyzed for lead, cadmium, and zinc. Whole crayfish were analyzed as composite samples of 5-60 animals. Metals concentrations were typically higher in samples from sites most heavily affected by mining and lowest in reference samples. Within the TSMD, most metals concentrations were higher at sites on the SR than on the NR and were typically highest in common carp and crayfish than in other taxa. Higher concentrations and greater risk were associated with fish and crayfish from heavily contaminated SR tributaries than the SR or NR mainstems. Based on the results of this and previous studies, the human consumption of carp and crayfish could be restricted based on current criteria for lead, cadmium, and zinc, and the consumption of channel catfish could be restricted due to lead. Metals concentrations were uniformly low in Micropterus spp. and crappie and would not warrant restriction, however. Some risk to carnivorous avian wildlife from lead and zinc in TSMD fish and invertebrates was also indicated, as was risk to the fish themselves. Overall, the wildlife assessment is consistent with previously reported biological effects attributed to metals

  20. Association of Dietary Intake and Biomarker Levels of Arsenic, Cadmium, Lead, and Mercury among Asian Populations in the United States: NHANES 2011–2012

    PubMed Central

    Awata, Hiroshi; Linder, Stephen; Mitchell, Laura E.; Delclos, George L.

    2016-01-01

    Background: We have recently shown that biomarker levels of selected metals are higher in Asians than in other U.S. ethnic groups, with important differences within selected Asian subgroups. Much of this difference may be dietary in origin; however, this is not well established. Objective: We evaluated dietary intake of toxic metals as a source of increased biomarker levels of metals among U.S. Asians. Methods: We estimated daily food consumption and dietary intake of arsenic, cadmium, lead, and mercury by combining 24-hr dietary intake recall data from the 2011–2012 National Health and Nutrition Examination Survey (NHANES) with data from the USDA Food Composition Intake Database and FDA Total Dietary Study. We analyzed associations between dietary metal intake and biomarker levels of the metals using linear regression. Further, estimated food consumption and metal intake levels were compared between Asians and other racial/ethnic groups (white, black, Mexican American, and other Hispanic) and within three Asian subgroups (Chinese, Indian Asian, and other Asians). Results: Significant associations (p < 0.05) were found between biomarker levels and estimated dietary metal intake for total and inorganic arsenic and mercury among Asians. Asians had the highest daily fish and rice consumption across the racial/ethnic groups. Fish was the major contributor to dietary mercury and total arsenic intake, whereas rice was the major contributor to inorganic arsenic dietary intake. Fish consumption across the Asian subgroups varied, with Asian Indians having lower fish consumption than the other Asian subgroups. Rice consumption was similar across the Asian subgroups. Conclusions: We confirmed that estimated dietary intake of arsenic (total and inorganic) and mercury is significantly associated with their corresponding biomarkers in U.S. Asians, using nationally representative data. In contrast, estimated dietary intake of cadmium and lead were not significantly associated

  1. Contamination of wells completed in the Roubidoux aquifer by abandoned zinc and lead mines, Ottawa County, Oklahoma

    USGS Publications Warehouse

    Christenson, Scott C.

    1995-01-01

    The Roubidoux aquifer in Ottawa County Oklahoma is used extensively as a source of water for public supplies, commerce, industry, and rural water districts. Water in the Roubidoux aquifer in eastern Ottawa County has relatively low dissolved-solids concentrations (less than 200 mg/L) with calcium, magnesium, and bicarbonate as the major ions. The Boone Formation is stratigraphically above the Roubidoux aquifer and is the host rock for zinc and lead sulfide ores, with the richest deposits located in the vicinity of the City of Picher. Mining in what became known as the Picher mining district began in the early 1900's and continued until about 1970. The water in the abandoned zinc and lead mines contains high concentrations of calcium, magnesium, bicarbonate, sulfate, fluoride, cadmium, copper, iron, lead, manganese, nickel, and zinc. Water from the abandoned mines is a potential source of contamination to the Roubidoux aquifer and to wells completed in the Roubidoux aquifer. Water samples were collected from wells completed in the Roubidoux aquifer in the Picher mining district and from wells outside the mining district to determine if 10 public supply wells in the mining district are contaminated. The chemical analyses indicate that at least 7 of the 10 public supply wells in the Picher mining district are contaminated by mine water. Application of the Mann-Whitney test indicated that the concentrations of some chemical constituents that are indicators of mine-water contamination are different in water samples from wells in the mining area as compared to wells outside the mining area. Application of the Wilcoxon signed-rank test showed that the concentrations of some chemical constituents that are indicators of mine-water contamination were higher in current (1992-93) data than in historic (1981-83) data, except for pH, which was lower in current than in historic data. pH and sulfate, alkalinity, bicarbonate, magnesium, iron, and tritium concentrations consistently

  2. Survey of Manual Methods of Measurements of Asbestos, Beryllium, Lead, Cadmium, Selenium, and Mercury in Stationary Source Emissions. Environmental Monitoring Series.

    ERIC Educational Resources Information Center

    Coulson, Dale M.; And Others

    The purpose of this study is to evaluate existing manual methods for analyzing asbestos, beryllium, lead, cadmium, selenium, and mercury, and from this evaluation to provide the best and most practical set of analytical methods for measuring emissions of these elements from stationary sources. The work in this study was divided into two phases.…

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

    MedlinePlus

    ... 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 ...

  4. Enhancement of emulsifier production by Curvularia lunata in cadmium, zinc and lead presence.

    PubMed

    Paraszkiewicz, Katarzyna; Frycie, Aleksandra; Słaba, Mirosława; Długoński, Jerzy

    2007-10-01

    The influence of cadmium, zinc and lead on fungal emulsifier synthesis and on the growth of filamentous fungus Curvularia lunata has been studied. Tolerance to heavy metals established for C. lunata was additionally compared with the sensitivity exhibited by strains of Curvularia tuberculata and Paecilomyces marquandii-fungi which do not secrete compounds of emulsifying activity. Although C. lunata, as the only one out of all studied fungi, exhibited the lowest tolerance to heavy metals when grown on a solid medium (in conditions preventing emulsifier synthesis), it manifested the highest tolerance in liquid culture - in conditions allowing exopolymer production. Cadmium, zinc and lead presented in liquid medium up to a concentration of 15 mM had no negative effect on C. lunata growth and stimulated emulsifier synthesis. In the presence of 15 mM of heavy metals, both the emulsifier and 24-h-old growing mycelium exhibited maximum sorption capacities, which were determined as 18.2 +/- 2.67, 156.1 +/- 10.32 mg g(-1) for Cd2+, 22.2 +/- 3.40, 95.2 +/- 14.21 mg g(-1) for Zn2+ and 51.1 +/- 1.85, 230.0 +/- 28.47 mg g(-1) for Pb2+ respectively. The results obtained by us in this work indicate that the emulsifier acts as a protective compound increasing the ability of C. lunata to survive in heavy metal polluted environment. Enhancement of exopolymer synthesis in the presence of Cd2+, Zn2+ and Pb2+ may also suggest, at least to some extent, a metal-specific nature of emulsifier production in C. lunata. Due to accumulation capability and tolerance to heavy metals, C. lunata mycelium surrounded by the emulsifier could be applied for toxic metal removal.

  5. Zinc supplementation in children with cystic fibrosis

    USDA-ARS?s Scientific Manuscript database

    Cystic fibrosis (CF) leads to malabsorption of macro- and micronutrients. Symptomatic zinc deficiency has been reported in CF but little is known about zinc homeostasis in children with CF. Zinc supplementation (Zn suppl) is increasingly common in children with CF but it is not without theoretcial r...

  6. Sierra Army Depot, Phase 1, Remedial Investigation/Feasibility Study, Lassen County, California. Final Remedial Investigation

    DTIC Science & Technology

    1991-10-01

    8.3.1.2 Cadmium ............................ 8-8 8.3.1.3 Lead .... ............................ 8-8 8.3.1.4 Zinc .... ............................ 8-8...Beryllium, Cadmium , Chromium, Cobalt, Copper, Fluoride Salts, Lead, Mercury, Molydenum, Nickel, Selenium, Silver, Thallium, Vanadium, Zinc . I ~ 2 ,4... cadmium (4.070 ;&g/L), copper (20.100 ug/L), and zinc (28.700 ug/L). Round 2 background 3 groundwater results include arsenic (7.700 g/L), barium

  7. Maternal and umbilical cord blood levels of mercury, lead, cadmium, and essential trace elements in Arctic Canada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Butler Walker, Jody; Houseman, Jan; Seddon, Laura

    Maternal and umbilical cord blood levels of mercury (Hg), lead (Pb), cadmium (Cd), and the trace elements copper (Cu), zinc (Zn), and selenium (Se) are reported for Inuit, Dene/Metis, Caucasian, and Other nonaboriginal participants from Arctic Canada. This is the first human tissue monitoring program covering the entire Northwest Territories and Nunavut for multiple contaminants and establishes a baseline upon which future comparisons can be made. Results for chlorinated organic pesticides and PCBs for these participants have been reported elsewhere. Between May 1994 and June 1999, 523 women volunteered to participate by giving their written informed consent, resulting in themore » collection of 386 maternal blood samples, 407 cord samples, and 351 cord:maternal paired samples. Geometric mean (GM) maternal total mercury (THg) concentrations ranged from 0.87{mu}g/L (SD=1.95) in the Caucasian group of participants (n=134) to 3.51{mu}g/L (SD=8.30) in the Inuit group (n=146). The GM of the Inuit group was 2.6-fold higher than that of the Dene/Metis group (1.35{mu}g/L, SD=1.60, n=92) and significantly higher than those of all other groups (P<0.0001). Of Inuit women participants, 3% (n=4) were within Health Canada's level of concern range (20-99{mu}g/L) for methylmercury (MeHg) exposure. Of Inuit and Dene/Metis cord samples, 56% (n=95) and 5% (n=4), respectively, exceeded 5.8{mu}g/L MeHg, the revised US Environmental Protection Agency lower benchmark dose. GM maternal Pb was significantly higher in Dene/Metis (30.9{mu}g/L or 3.1{mu}g/dL; SD=29.1{mu}g/L) and Inuit (31.6{mu}g/L, SD=38.3) participants compared with the Caucasian group (20.6{mu}g/L, SD=17.9) (P<0.0001). Half of all participants were smokers. GM blood Cd in moderate smokers (1-8 cigarettes/day) and in heavy smokers (>8 cigarettes/day) was 7.4-fold higher and 12.5-fold higher, respectively, than in nonsmokers. The high percentage of smokers among Inuit (77%) and Dene/Metis (48%) participants highlights the

  8. Biotransference and biomagnification of selenium copper, cadmium, zinc, arsenic and lead in a temperate seagrass ecosystem from Lake Macquarie Estuary, NSW, Australia.

    PubMed

    Barwick, M; Maher, W

    2003-10-01

    In this study the biotransference of selenium copper, cadmium, zinc, arsenic and lead was measured in a contaminated seagrass ecosystem in Lake Macquarie, NSW, Australia, to determine if biomagnification of these trace metals is occurring and if they reach concentrations that pose a threat to the resident organisms or human consumers. Selenium was found to biomagnify, exceeding maximum permitted concentrations for human consumption within carnivorous fish tissue, the highest trophic level examined. Selenium concentrations measured within carnivorous fish were also above those shown to elicit sub-lethal effects in freshwater fish. As comparisons are made to selenium concentrations known to effect freshwater fish, inferences must be made with caution. There was no evidence of copper, cadmium, zinc or lead biomagnification within the food web examined. Copper, cadmium, zinc and lead concentrations were below concentrations shown to elicit adverse responses in biota. Copper concentrations within crustaceans M. bennettae and P. palagicus were found to exceed maximum permitted concentrations for human consumption. It is likely that copper concentrations within these species were accumulated due to the essential nature of this trace metal for many species of molluscs and crustaceans. Arsenic showed some evidence of biomagnification. Total arsenic concentrations are similar to those found in other uncontaminated marine ecosystems, thus arsenic concentrations are unlikely to cause adverse effects to aquatic organisms. Inorganic arsenic concentrations are below maximum permitted concentrations for human consumption.

  9. [Simultaneous determination of trace amounts of zinc, cadmium, lead and copper by the method of anodic voltammetry using factor experimental design].

    PubMed

    Koen, E

    1975-01-01

    Using the method of factor planning of the experiment, the author studies and demonstrates the influence exerted by the potential and time of electrolysis, and by the concentration of the background and elements on the heights of anodal peaks upon simultaneous determination of zinc, cadmium, lead and copper microconcentrations. On the ground of statistical elaboration of the results, the optimal condition for polarographic determination through anodal voltamperometry are outlined. According to the cyclic voltametry method, the electrod processes reversibility for zinc, cadmium and lead, as well as the incomplete reversibility for copper are established; the number of electrons participating in the electrochemical reaction are found using the method of gas coulometry. The possibility of simultaneous determination of the four elements' ultramicroconcentrations after the method of voltamperometry with enrichment is proved. The standard deviation is in the range 3.02 to 4.9.

  10. Contamination of houses by workers occupationally exposed in a lead-zinc-copper mine and impact on blood lead concentrations in the families.

    PubMed Central

    Chiaradia, M; Gulson, B L; MacDonald, K

    1997-01-01

    OBJECTIVE: To evaluate the pathway of leaded dust from a lead-zinc-copper mine to houses of employees, and the impact on blood lead concentrations (PbB) of children. METHODS: High precision lead isotope and lead concentration data were obtained on venous blood and environmental samples (vacuum cleaner dust, interior dustfall accumulation, water, paint) for eight children of six employees (and the employees) from a lead-zinc-copper mine. These data were compared with results for 11 children from occupationally unexposed control families living in the same city. RESULTS: The median (range) concentrations of lead in vacuum cleaner dust was 470 (21-1300) ppm. In the houses of the mine employees, vacuum cleaner dust contained varying higher proportions of mine lead than did airborne particulate matter measured as dustfall accumulated over a three month period. The median (range) concentrations of lead in soil were 30 (5-407) ppm and these showed no evidence of any mine lead. Lead in blood of the mine employees varied from 7 to 25 micrograms/dl and was generally dominated by mine lead (> 60%). The mean (SD) PbB in the children of the mine employees was 5.7 (1.7) micrograms/dl compared with 4.1 (1.4) micrograms/dl for the control children (P = 0.02). The PbB of all children was always < 10 micrograms/dl, the Australian National Health and Medical Research Council goal for all Australians. Some of the control children had higher PbB than the children of mine employees, probably from exposure to leaded paint as six of the eight houses of the control children were > 50 years old. In five of the eight children of mine employees > 20% of PbB was from the lead mine. However, in the other three cases of children of mine employees, their PbB was from sources other than mine lead (paint, petrol, background sources). CONCLUSIONS: Houses of employees from a lead mine can be contaminated by mine lead even if they are not situated in the same place as the mine. Delineation of the mine

  11. How Tiny Collisions Shape Mercury

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2017-07-01

    distribution of directions from which micrometeoroids strike Mercury during its yearly orbit.Schematic of Mercury in its orbit around the Sun. The dawn side leads the orbital motion, while the dusk side trails it.Geometry of an OrbitMercurys orbit is unique in our solar system: it circles the Sun twice for every three rotations on its own axis so if you were on Mercury, youd see a single day pass over the span of two years. As with all prograde planets, the edge leading the Mercurys orbit marks the dawn terminator, while the edge trailing the planets orbital motion marks the dusk terminator.Pokorn and collaborators find a significant asymmetry in the impact vaporization that occurs on Mercurys dawn side versus its dusk side. This is due to impact geometry (since the dusk side is shielded from impacts in the direction of motion) and seasonal variation of the dust/meteoroid environment around the planet. The authors show that the source of impact vaporization shifts toward the nightside as Mercury approaches aphelion, and toward the dayside when the planet approaches the Sun.Importance of Long-Period CometsSeasonal variations of the relative vaporization rate from the authors model (black line) compared to measurements of Mercurys exospheric abundance of Ca. The contribution of long-period comets is shown by the blue line. [Pokorn et al. 2017]The dawn/dusk asymmetry and the seasonal variations predicted by the model are all nicely consistent NASAs MESSENGER spacecraft observations of the metal distribution in Mercurys exosphere.What makes Pokorn and collaborators model work so well? Their inclusion of the long-period, Halley-type comets is key: the high impact velocity of the micrometeoroids produced by this family play a significant role in shaping the impact vaporization rate of Mercurys surface.This work successfully demonstrates that we can use measurements of Mercurys exosphere as a unique tool to constrain the dust population in the inner solar system.CitationPetr Pokorn

  12. Biomonitoring of arsenic, cadmium, lead, manganese and mercury in urine and hair of children living near mining and industrial areas.

    PubMed

    Molina-Villalba, Isabel; Lacasaña, Marina; Rodríguez-Barranco, Miguel; Hernández, Antonio F; Gonzalez-Alzaga, Beatriz; Aguilar-Garduño, Clemente; Gil, Fernando

    2015-04-01

    Huelva (South West Spain) and its surrounding municipalities represent one of the most polluted estuaries in the world owing to the discharge of mining and industrial related pollutants in their proximity. A biomonitoring study was conducted to assess exposure to arsenic and some trace metals (cadmium, mercury, manganese and lead) in urine and scalp hair from a representative sample of children aged 6-9 years (n=261). This is the only study simultaneously analyzing those five metal elements in children urine and hair. The potential contribution of gender, water consumption, residence area and body mass index on urinary and hair metal concentrations was also studied. Urine levels of cadmium and total mercury in a proportion (25-50%) of our children population living near industrial/mining areas might have an impact on health, likely due to environmental exposure to metal pollution. The only significant correlation between urine and hair levels was found for mercury. Children living near agriculture areas showed increased levels of cadmium and manganese (in urine) and arsenic (in hair). In contrast, decreased urine Hg concentrations were observed in children living near mining areas. Girls exhibited significantly higher trace metal concentrations in hair than boys. The greatest urine arsenic concentrations were found in children drinking well/spring water. Although human hair can be a useful tool for biomonitoring temporal changes in metal concentrations, levels are not correlated with those found in urine except for total mercury, thus providing additional information. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Zinc in human health: effect of zinc on immune cells.

    PubMed

    Prasad, Ananda S

    2008-01-01

    pathway, decreases NF-kappaB activation, leading to decreased gene expression and generation of tumor necrosis factor-alpha (TNF-alpha), IL-1beta, and IL-8. We have reported recently that in both young adults and elderly subjects, zinc supplementation decreased oxidative stress markers and generation of inflammatory cytokines.

  14. Mercury and autism: accelerating evidence?

    PubMed

    Mutter, Joachim; Naumann, Johannes; Schneider, Rainer; Walach, Harald; Haley, Boyd

    2005-10-01

    The causes of autism and neurodevelopmental disorders are unknown. Genetic and environmental risk factors seem to be involved. Because of an observed increase in autism in the last decades, which parallels cumulative mercury exposure, it was proposed that autism may be in part caused by mercury. We review the evidence for this proposal. Several epidemiological studies failed to find a correlation between mercury exposure through thimerosal, a preservative used in vaccines, and the risk of autism. Recently, it was found that autistic children had a higher mercury exposure during pregnancy due to maternal dental amalgam and thimerosal-containing immunoglobulin shots. It was hypothesized that children with autism have a decreased detoxification capacity due to genetic polymorphism. In vitro, mercury and thimerosal in levels found several days after vaccination inhibit methionine synthetase (MS) by 50%. Normal function of MS is crucial in biochemical steps necessary for brain development, attention and production of glutathione, an important antioxidative and detoxifying agent. Repetitive doses of thimerosal leads to neurobehavioral deteriorations in autoimmune susceptible mice, increased oxidative stress and decreased intracellular levels of glutathione in vitro. Subsequently, autistic children have significantly decreased level of reduced glutathione. Promising treatments of autism involve detoxification of mercury, and supplementation of deficient metabolites.

  15. Mercury cycling in peatland watersheds. Chapter 11.

    Treesearch

    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...

  16. From Orbit, Looking toward Mercury's Horizon

    NASA Image and Video Library

    2017-12-08

    NASA image acquired: March 29, 2011 MESSENGER acquired this image of Mercury's horizon as the spacecraft was moving northward along the first orbit during which MDIS was turned on. Bright rays from Hokusai can be seen running north to south in the image. MDIS frequently acquired images that contained Mercury's horizon during the mission's three Mercury flybys. (Visit these links to see examples of horizon images from Mercury flyby 1, Mercury flyby 2, and Mercury flyby 3.) However, now that MESSENGER is in orbit about Mercury, views of Mercury's horizon in the images will be much less common. The field of view for MDIS will generally be filled with Mercury's surface as the instrument maps out the planet's geology in high resolution, stereo, and color. Occasionally, in order to obtain images of a certain portion of Mercury's surface, the horizon will also be visible. On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook

  17. A thin, dense crust for Mercury

    NASA Astrophysics Data System (ADS)

    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.

  18. Geochemical investigation of potentially harmful elements in household dust from a mercury-contaminated site, the town of Idrija (Slovenia).

    PubMed

    Bavec, Špela; Gosar, Mateja; Miler, Miloš; Biester, Harald

    2017-06-01

    A comprehensive geochemical investigation of potentially harmful elements (PHEs) in household dust from the town of Idrija (Slovenia), once a world-famous Hg mining town that is now seriously polluted, was performed for the first time. After aqua regia digestion, the content of mercury (Hg), arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), molybdenum (Mo), nickel (Ni), lead (Pb) and zinc (Zn) was measured. PHE-bearing particles were recognised and observed by scanning electron microscopy and energy-dispersive spectrometry before and after exposure to simulated stomach acid (SSA). Mercury binding forms were identified by Hg thermal desorption technique and gastric bioaccessible Hg was estimated after SSA extraction by ICP-MS. With regard to rural and urban background values for Slovenia, high Hg content (6-120 mg/kg) and slightly elevated As content (1-13 mg/kg) were found. Mercury pollution is a result of past mining and ore processing activities. Arsenic content is potentially associated with As enrichment in local soils. Four Hg binding forms were identified: all samples contained Hg bound to the dust matrix, 14 samples contained cinnabar, two samples contained metallic Hg (Hg 0 ), and one sample assumingly contained mercury oxide. After exposure to SSA, Hg-bearing phases showed no signs of dissolution, while other PHE-bearing phases were significantly morphologically and/or chemically altered. Estimated gastric Hg bioaccessibility was low (<0.006-0.09 %), which is in accordance with identified Hg binding forms and high organic carbon content (15.9-31.5 %) in the dust samples.

  19. Composition of the edible portion of raw (fresh or frozen) crustaceans, finfish, and mollusks. III. Microelements. [Review

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sidwell, V.D.; Loomis, A.L.; Loomis, K.J.

    1978-09-01

    This report summarizes data from 224 publications referring to the microelements found in the flesh of commonly eaten seafoods. These microelements are: copper, iron, zinc, iodine, manganese, mercury, organic mercury, lead arsenic, fluorine, silver, cadmium, cobalt, selenium, chromium, vanadium, tin, aluminum, nickel, barium, and molybdenum.

  20. Zinc supplementation leads to immune modulation and improved survival in a juvenile model of murine sepsis.

    PubMed

    Ganatra, Hammad A; Varisco, Brian M; Harmon, Kelli; Lahni, Patrick; Opoka, Amy; Wong, Hector R

    2017-01-01

    Children with severe sepsis are known to have altered zinc homeostasis and decreased circulating zinc levels, suggesting a role for zinc supplementation to improve outcomes. We tested the hypothesis that zinc supplementation would improve survival in a juvenile model of polymicrobial sepsis. Juvenile (13-14-d-old) C57BL/6 mice were treated with 10 mg/kg of zinc via i.p. injections (or vehicle) for 3 d prior to induction of polymicrobial sepsis via i.p. cecal slurry injections. Survival after sepsis was followed for 3 d, and bacterial clearance, ex vivo phagocytosis, systemic inflammatory markers and neutrophil extracellular trap (NET) formation were quantified. We found a significant survival benefit and decreased bacterial burden among zinc supplemented mice when compared with the control group. Zinc supplementation also resulted in enhanced phagocytic activity, greater neutrophil recruitment in the peritoneal cavity and NET formation, suggesting a possible mechanism for improved bacterial clearance and survival. We also noted decreased serum cytokine levels and decreased myeloperoxidase activity in lung tissue following zinc supplementation, suggesting attenuation of the systemic inflammatory response. In conclusion, zinc supplementation improves bacterial clearance, and hence survival, in juvenile mice with polymicrobial sepsis.

  1. Mercury

    MedlinePlus

    Mercury is an element that is found in air, water and soil. It has several forms. Metallic mercury is a shiny, silver-white, odorless liquid. If ... with other elements to form powders or crystals. Mercury is in many products. Metallic mercury is used ...

  2. 40 CFR 421.254 - Standards of performance for new sources.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... average mg/troy ounce of gold refined electrolytically Lead 5.544 2.574 Mercury 2.970 1.188 Silver 5.742 2... property Maximum for any 1 day Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0... reduced in solution Lead 0.112 0.052 Mercury 0.060 0.024 Silver 0.116 0.048 Zinc 0.408 0.168 Gold 0.040...

  3. Blood levels of lead, cadmium, and mercury in the elderly living in institutionalized care in the Czech Republic.

    PubMed

    Rambousková, Jolana; Krsková, Andrea; Slavíková, Miroslava; Cejchanová, Mája; Cerná, Milena

    2014-10-01

    There is limited research examining the chemical load of toxic metals in the elderly. The aim of the present study was two-fold: to determine the body burden of lead, cadmium and mercury in association with age, gender, locality, lifestyle factors and potential health impacts among this population and to compare the values with blood values from the general Czech population aged 18-64 years. Lead, cadmium and mercury were examined in the blood of institutionalized senior citizens (46 males, 151 females aged 61-100 years) from two localities in the Czech Republic (Prague and Teplice) from 2009 through 2011. Measurements were made using inductively coupled plasma mass spectrometry (Pb, Cd) and a single purpose spectrometer AMA 254 (Hg). Geometric means (GM) of whole blood lead (B-Pb), cadmium (B-Cd) and mercury (B-Hg) levels were 25.3μg/l, 0.55μg/l and 0.21μg/l, respectively. No age-related differences were found for B-Pb and B-Cd levels but a negative correlation with age was observed for B-Hg levels (p=0.04). B-Pb levels in men were significantly higher than in women (GM 29.9μg/l vs. 24.1μg/l). B-Cd was significantly higher in women (GM 0.57μg/l) than in men (0.50μg/l) (p=0.007) and in smokers (GM 1.29μg/l) than in nonsmokers (GM 0.53μg/l) (p=<0.001) and in seniors from Prague (GM 0.60μg/l) compared to those from Teplice (GM 0.43μg/l) (p=<0.001). Seniors with a history of chronic kidney disease, stroke and those using psycho-pharmaceuticals had higher B-Pb levels (p=0.008, 0.04 and 0.05, resp.), seniors diagnosed with atherosclerosis had higher B-Cd levels (p=0.002) and seniors using psycho-pharmaceuticals had higher B-Hg levels (p=0.07). B-Hg levels were also positively correlated with blood albumin levels (p=0.015). This study provides data on levels of heavy metals in a group of elderly people. Such information is very scarce. Associations with diseases should be the subject of further investigation. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Trace level voltammetric determination of heavy metals and total mercury in tea matrices (Camellia sinensis).

    PubMed

    Melucci, Dora; Locatelli, Marcello; Locatelli, Clinio

    2013-12-01

    An analytical procedure regarding the voltammetric determination of mercury(II), copper(II), lead(II), cadmium(II) and zinc(II) by square wave anodic stripping voltammetry (SWASV) in matrices involved in food chain is proposed. In particular, tea leaves were analyzed as real samples. The digestion of each matrix was carried out using a concentrated HCl-HNO3-H2SO4 acidic attack mixture; 0.01 mol L(-1) EDTA-Na2+ 0.15 mol L(-1) NaCl + 0.5 mol L(-1) HCl was employed as the supporting electrolyte. The voltammetric measurements were carried out using a conventional three electrode cell, employing, as working electrodes, a gold electrode (GE) and a stationary hanging mercury drop electrode (HMDE). The analytical procedure has been verified on the standard reference materials Spinach Leaves NIST-SRM 1570a, Tomato Leaves NIST-SRM 1573a and Apple Leaves NIST-SRM 1515. For all the elements, the precision as repeatability, expressed as relative standard deviation (sr) was of the order of 3-5%, while the trueness, expressed as relative error (e) was of the order of 3-7%. Once set up on the standard reference materials, the analytical procedure was applied to commercial tea leaves samples. A critical comparison with spectroscopic measurements is also discussed.

  5. Zinc Signal in Brain Diseases.

    PubMed

    Portbury, Stuart D; Adlard, Paul A

    2017-11-23

    The divalent cation zinc is an integral requirement for optimal cellular processes, whereby it contributes to the function of over 300 enzymes, regulates intracellular signal transduction, and contributes to efficient synaptic transmission in the central nervous system. Given the critical role of zinc in a breadth of cellular processes, its cellular distribution and local tissue level concentrations remain tightly regulated via a series of proteins, primarily including zinc transporter and zinc import proteins. A loss of function of these regulatory pathways, or dietary alterations that result in a change in zinc homeostasis in the brain, can all lead to a myriad of pathological conditions with both acute and chronic effects on function. This review aims to highlight the role of zinc signaling in the central nervous system, where it may precipitate or potentiate diverse issues such as age-related cognitive decline, depression, Alzheimer's disease or negative outcomes following brain injury.

  6. Leptin, NPY, Melatonin and Zinc Levels in Experimental Hypothyroidism and Hyperthyroidism: The Relation to Zinc.

    PubMed

    Baltaci, Abdulkerim Kasım; Mogulkoc, Rasim

    2017-06-01

    Since zinc mediates the effects of many hormones or is found in the structure of numerous hormone receptors, zinc deficiency leads to various functional impairments in the hormone balance. And also thyroid hormones have important activity on metabolism and feeding. NPY and leptin are affective on food intake and regulation of appetite. The present study is conducted to determine how zinc supplementation and deficiency affect thyroid hormones (free and total T3 and T4), melatonin, leptin, and NPY levels in thyroid dysfunction in rats. The experiment groups in the study were formed as follows: Control (C); Hypothyroidism (PTU); Hypothyroidism+Zinc (PTU+Zn); Hypothyroidism+Zinc deficient; Hyperthyroidism (H); Hyperthyroidism+Zinc (H+Zn); and Hyperthyroidism+Zinc deficient. Thyroid hormone parameters (FT 3 , FT 4 , TT 3 , and TT 4 ) were found to be reduced in hypothyroidism groups and elevated in the hyperthyroidism groups. Melatonin values increased in hyperthyroidism and decreased in hypothyroidism. Leptin and NPY levels both increased in hypo- and hyperthyroidism. Zinc levels, on the other hand, decreased in hypothyroidism and increased in hyperthyroidism. Zinc supplementation, particularly when thyroid function is impaired, has been demonstrated to markedly prevent these changes.

  7. Leaching assessment of road materials containing primary lead and zinc slags.

    PubMed

    Barna, R; Moszkowicz, P; Gervais, C

    2004-01-01

    Characterisation of the leaching behaviour of waste-containing materials is a crucial step in the environmental assessment for reuse scenarios. In our research we applied the multi-step European methodology ENV 12-920 to the leaching assessment of road materials containing metallurgical slag. A Zn slag from an imperial smelting furnace (ISF) and a Pb slag from a lead blast furnace (LBF) are investigated. The two slags contain up to 11.2 wt% of lead and 3.5 wt% of zinc and were introduced as a partial substitute for sand in two road materials, namely sand-cement and sand-bitumen. At the laboratory scale, a leaching assessment was performed first through batch equilibrium leaching tests. Second, the release rate of the contaminants was evaluated using saturated leaching tests on monolithic material. Third, laboratory tests were conducted on monolithic samples under intermittent wetting conditions. Pilot-scale tests were conducted for field testing of intermittent wetting conditions. The results show that the release of Pb and Zn from the materials in a saturated scenario was controlled by the pH of the leachates. For the intermittent wetting conditions, an additional factor, blocking of the pores by precipitation during the drying phase is proposed. Pilot-scale leaching behaviour only partially matched with the laboratory-scale test results: new mass transfer mechanisms and adapted laboratory leaching tests are discussed.

  8. On the Edge of Mercury

    NASA Image and Video Library

    2015-02-04

    In this image, Mercury's horizon cuts a striking edge against the stark blackness of space. On the right, sunlight harshly brings the landscape into relief while on the left, the surface is shrouded in the darkness of night. This image was acquired as part of MDIS's limb imaging campaign. Once per week, MDIS captures images of Mercury's limb, with an emphasis on imaging the southern hemisphere limb. These limb images provide information about Mercury's shape and complement measurements of topography made by the Mercury Laser Altimeter (MLA) of Mercury's northern hemisphere. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. In the mission's more than three years of orbital operations, MESSENGER has acquired over 250,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  9. Analysis of cellular responses of macrophages to zinc ions and zinc oxide nanoparticles: a combined targeted and proteomic approach.

    PubMed

    Triboulet, Sarah; Aude-Garcia, Catherine; Armand, Lucie; Gerdil, Adèle; Diemer, Hélène; Proamer, Fabienne; Collin-Faure, Véronique; Habert, Aurélie; Strub, Jean-Marc; Hanau, Daniel; Herlin, Nathalie; Carrière, Marie; Van Dorsselaer, Alain; Rabilloud, Thierry

    2014-06-07

    Two different zinc oxide nanoparticles, as well as zinc ions, are used to study the cellular responses of the RAW 264 macrophage cell line. A proteomic screen is used to provide a wide view of the molecular effects of zinc, and the most prominent results are cross-validated by targeted studies. Furthermore, the alteration of important macrophage functions (e.g. phagocytosis) by zinc is also investigated. The intracellular dissolution/uptake of zinc is also studied to further characterize zinc toxicity. Zinc oxide nanoparticles dissolve readily in the cells, leading to high intracellular zinc concentrations, mostly as protein-bound zinc. The proteomic screen reveals a rather weak response in the oxidative stress response pathway, but a strong response both in the central metabolism and in the proteasomal protein degradation pathway. Targeted experiments confirm that carbohydrate catabolism and proteasome are critical determinants of sensitivity to zinc, which also induces DNA damage. Conversely, glutathione levels and phagocytosis appear unaffected at moderately toxic zinc concentrations.

  10. Lead, mercury, and cadmium exposure and attention deficit hyperactivity disorder in children.

    PubMed

    Kim, Stephani; Arora, Monica; Fernandez, Cristina; Landero, Julio; Caruso, Joseph; Chen, Aimin

    2013-10-01

    There is limited research examining the relationship between lead (Pb) exposure and medically diagnosed attention deficit hyperactivity disorder (ADHD) in children. The role of mercury (Hg) and cadmium (Cd) exposures in ADHD development is even less clear. To examine the relationship between Pb, Hg, and Cd and ADHD in children living inside and outside a Lead Investigation Area (LIA) of a former lead refinery in Omaha, NE. We carried out a case-control study with 71 currently medically diagnosed ADHD cases and 58 controls from a psychiatric clinic and a pediatric clinic inside and outside of the LIA. The participants were matched on age group (5-8, 9-12 years), sex, race (African American or Caucasians and others), and location (inside or outside LIA). We measured whole blood Pb, total Hg, and Cd using inductively coupled plasma mass spectrometry. Inside the LIA, the 27 cases had blood Pb geometric mean (GM) 1.89 µg/dL and the 41 controls had 1.51 µg/dL. Outside the LIA, the 44 cases had blood Pb GM 1.02 µg/dL while the 17 controls had 0.97 µg/dL. After adjustment for matching variables and maternal smoking, socioeconomic status, and environmental tobacco exposure, each natural log unit blood Pb had an odds ratio of 2.52 with 95% confidence interval of 1.07-5.92. Stratification by the LIA indicated similar point estimate but wider CIs. No associations were observed for Hg or Cd. Postnatal Pb exposure may be associated with higher risk of clinical ADHD, but not the postnatal exposure to Hg or Cd. © 2013 Published by Elsevier Inc.

  11. Lead, Mercury, and Cadmium Exposure and Attention Deficit Hyperactivity Disorder in Children

    PubMed Central

    Kim, Stephani; Arora, Monica; Fernandez, Cristina; Caruso, Joseph; Landero, Julio; Chen, Aimin

    2013-01-01

    Background There is limited research examining the relationship between lead (Pb) exposure and medically diagnosed Attention Deficit Hyperactivity Disorder (ADHD) in children. The role of mercury (Hg) and cadmium (Cd) exposures in ADHD development is even less clear. Objectives To examine the relationship between Pb, Hg, and Cd and ADHD in children living inside and outside a Lead Investigation Area (LIA) of a former lead refinery in Omaha, NE. Methods We carried out a case-control study with 71 currently medically diagnosed ADHD cases and 58 controls from a psychiatric clinic and a pediatric clinic inside and outside of the LIA. The participants were matched on age group (5–8, 9–12 years), sex, race (African American or Caucasians and Others), and location (inside or outside LIA). We measured whole blood Pb, total Hg, and Cd using Inductively Coupled Plasma Mass Spectrometry. Results Inside the LIA, the 27 cases had blood Pb Geometric Mean (GM) 1.89 µg/dL and the 41 controls had 1.51 µg/dL. Outside the LIA, the 44 cases had blood Pb GM 1.02 µg/dL while the 17 controls had 0.97 µg/dL. After adjustment for matching variables and maternal smoking, socioeconomic status, and environmental tobacco exposure, each natural log unit blood Pb had an odds ratio of 2.52 with 95% confidence interval of 1.07–5.92. Stratification by the LIA indicated similar point estimate but wider CIs. No associations were observed for Hg or Cd. Conclusions Postnatal Pb exposure may be associated with higher risk of clinical ADHD, but not the postnatal exposure to Hg or Cd. PMID:24034783

  12. Got Mercury?

    NASA Technical Reports Server (NTRS)

    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

  13. Concentrations of arsenic, copper, cobalt, lead and zinc in cassava (Manihot esculenta Crantz) growing on uncontaminated and contaminated soils of the Zambian Copperbelt

    NASA Astrophysics Data System (ADS)

    Kříbek, B.; Majer, V.; Knésl, I.; Nyambe, I.; Mihaljevič, M.; Ettler, V.; Sracek, O.

    2014-11-01

    The concentrations of arsenic (As), copper (Cu), cobalt (Co), lead (Pb) and zinc (Zn) in washed leaves and washed and peeled tubers of cassava (Manihot esculenta Crantz, Euphorbiaceae) growing on uncontaminated and contaminated soils of the Zambian Copperbelt mining district have been analyzed. An enrichment index (EI) was used to distinguish between contaminated and uncontaminated areas. This index is based on the average ratio of the actual and median concentration of the given contaminants (As, Co, Cu, mercury (Hg), Pb and Zn) in topsoil. The concentrations of copper in cassava leaves growing on contaminated soils reach as much as 612 mg kg-1 Cu (total dry weight [dw]). Concentrations of copper in leaves of cassava growing on uncontaminated soils are much lower (up to 252 mg kg-1 Cu dw). The concentrations of Co (up to 78 mg kg-1 dw), As (up to 8 mg kg-1 dw) and Zn (up to 231 mg kg-1 dw) in leaves of cassava growing on contaminated soils are higher compared with uncontaminated areas, while the concentrations of lead do not differ significantly. The concentrations of analyzed chemical elements in the tubers of cassava are much lower than in its leaves with the exception of As. Even in strongly contaminated areas, the concentrations of copper in the leaves and tubers of cassava do not exceed the daily maximum tolerance limit of 0.5 mg kg-1/human body weight (HBW) established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). The highest tolerable weekly ingestion of 0.025 mg kg-1/HBW for lead and the highest tolerable weekly ingestion of 0.015 mg kg-1/HBW for arsenic are exceeded predominantly in the vicinity of smelters. Therefore, the preliminary assessment of dietary exposure to metals through the consumption of uncooked cassava leaves and tubers has been identified as a moderate hazard to human health. Nevertheless, as the surfaces of leaves are strongly contaminated by metalliferous dust in the polluted areas, there is still a potential hazard

  14. The zinc paradigm for metalloneurochemistry.

    PubMed

    Barr, Chelsea A; Burdette, Shawn C

    2017-05-09

    Neurotransmission and sensory perception are shaped through metal ion-protein interactions in various brain regions. The term "metalloneurochemistry" defines the unique field of bioinorganic chemistry focusing on these processes, and zinc has been the leading target of metalloneurochemists in the almost 15 years since the definition was introduced. Zinc in the hippocampus interacts with receptors that dictate ion flow and neurotransmitter release. Understanding the intricacies of these interactions is crucial to uncovering the role that zinc plays in learning and memory. Based on receptor similarities and zinc-enriched neurons (ZENs) in areas of the brain responsible for sensory perception, such as the olfactory bulb (OB), and dorsal cochlear nucleus (DCN), zinc participates in odor and sound perception. Development and improvement of methods which allow for precise detection and immediate manipulation of zinc ions in neuronal cells and in brain slices will be critical in uncovering the synaptic action of zinc and, more broadly, the bioinorganic chemistry of cognition. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  15. NASA's SDO Captures Mercury Transit Time-lapses SDO Captures Mercury Transit Time-lapse

    NASA Image and Video Library

    2017-12-08

    Less than once per decade, Mercury passes between the Earth and the sun in a rare astronomical event known as a planetary transit. The 2016 Mercury transit occurred on May 9th, between roughly 7:12 a.m. and 2:42 p.m. EDT. The images in this video are from NASA’s Solar Dynamics Observatory Music: Encompass by Mark Petrie For more info on the Mercury transit go to: www.nasa.gov/transit This video is public domain and may be downloaded at: svs.gsfc.nasa.gov/12235 NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  16. Cadmium, lead, tin, total mercury, and methylmercury in canned tuna commercialised in São Paulo, Brazil.

    PubMed

    de Paiva, Esther Lima; Morgano, Marcelo Antonio; Milani, Raquel Fernanda

    2017-09-01

    The objective of this work was to determine levels of inorganic contaminants in 30 samples of five commercial brands of canned tuna, acquired on the local market in Campinas, São Paulo, Brazil, in the year of 2015. Total mercury and methylmercury (MeHg+) were determined by atomic absorption with thermal decomposition and amalgamation; and cadmium, lead, and tin were determined by inductively coupled plasma optical emission spectrometry. Results indicated that 20% of the tuna samples surpassed limits determined by the Brazilian and European Commission legislation for cadmium; for lead, the maximum value found was 59 µg kg -1 and tin was not detected in any samples. The maximum values found for total Hg and MeHg+ were 261 and 258 µg kg -1 , respectively. As from the results obtained, it was estimated that the consumption of four cans per week (540 g) of tuna canned in water could surpass the provisional tolerable monthly intake for MeHg + by 100%.

  17. Corbicula fluminea as a Bioaccumulation Indicator Species: A Case Study at the Columbia and Willamette Rivers

    DTIC Science & Technology

    2009-06-01

    metals including mercury (Hg), lead (Pb), zinc (Zn), and cadmium (Cd). The analytical methods used by the laboratories and sample identifications...moderate levels of mercury (46.5 ng/g), and undetectable levels of cadmium (< 0.1 μg/g). Within the large group, the first subgroup was a singleton...www.issg.org/database/. Inza, B., F. Ribeyre, and A. Boudou. 1998. Dynamics of cadmium and mercury compounds (inorganic mercury or methylmercury): Uptake

  18. Enhanced zinc consumption causes memory deficits and increased brain levels of zinc

    USGS Publications Warehouse

    Flinn, J.M.; Hunter, D.; Linkous, D.H.; Lanzirotti, A.; Smith, L.N.; Brightwell, J.; Jones, B.F.

    2005-01-01

    Zinc deficiency has been shown to impair cognitive functioning, but little work has been done on the effects of elevated zinc. This research examined the effect on memory of raising Sprague-Dawley rats on enhanced levels of zinc (10 ppm ZnCO3; 0.153 mM) in the drinking water for periods of 3 or 9 months, both pre- and postnatally. Controls were raised on lab water. Memory was tested in a series of Morris Water Maze (MWM) experiments, and zinc-treated rats were found to have impairments in both reference and working memory. They were significantly slower to find a stationary platform and showed greater thigmotaxicity, a measure of anxiety. On a working memory task, where the platform was moved each day, zinc-treated animals had longer latencies over both trials and days, swam further from the platform, and showed greater thigmotaxicity. On trials using an Atlantis platform, which remained in one place but was lowered on probe trials, the zinc-treated animals had significantly fewer platform crossings, spent less time in the target quadrant, and did not swim as close to the platform position. They had significantly greater latency on nonprobe trials. Microprobe synchrotron X-ray fluorescence (??SXRF) confirmed that brain zinc levels were increased by adding ZnCO 3 to the drinking water. These data show that long-term dietary administration of zinc can lead to impairments in cognitive function. ?? 2004 Elsevier Inc. All rights reserved.

  19. Mercury study report to Congress. Volume 5. Health effects of mercury and mercury compounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hassett-Sipple, B.; Swartout, J.; Schoeny, R.

    1997-12-01

    This volume summarizes the available information on human health effects and animal data for hazard identification and dose-response assessment for three forms of mercury: elemental mercury, mercury chloride (inorganic mercury), and methylmercury (organic mercury). Effects are summarized by endpoint. The risk assessment evaluates carcinogenicity, mutagenicity, developmental toxicity and general systemic toxicity of these chemical species of mercury. Toxicokinetics (absorption, distribution, metabolism and excretion) are described for each of the three mercury species. Reference doses are calculated for inorganic and methylmercury; a reference concentrations for inhaled elemental mercury is provided. A quantitative analysis of factors contributing to variability and uncertainty inmore » the methylmercury RfD is provided in an appendix. Interactions and sensitive populations are described. the draft volume assesses ongoing research and research needs to reduce uncertainty surrounding adverse human health consequences of methylmercury exposure.« less

  20. Mercury transport and human exposure from global marine fisheries.

    PubMed

    Lavoie, Raphael A; Bouffard, Ariane; Maranger, Roxane; Amyot, Marc

    2018-04-30

    Human activities have increased the global circulation of mercury, a potent neurotoxin. Mercury can be converted into methylmercury, which biomagnifies along aquatic food chains and leads to high exposure in fish-eating populations. Here we quantify temporal trends in the ocean-to-land transport of total mercury and methylmercury from fisheries and we estimate potential human mercury intake through fish consumption in 175 countries. Mercury export from the ocean increased over time as a function of fishing pressure, especially on upper-trophic-level organisms. In 2014, over 13 metric tonnes of mercury were exported from the ocean. Asian countries were important contributors of mercury export in the last decades and the western Pacific Ocean was identified as the main source. Estimates of per capita mercury exposure through fish consumption showed that populations in 38% of the 175 countries assessed, mainly insular and developing nations, were exposed to doses of methylmercury above governmental thresholds. Our study shows temporal trends and spatial patterns of Hg transport by fisheries. Given the high mercury intake through seafood consumption observed in several understudied yet vulnerable coastal communities, we recommend a comprehensive assessment of the health exposure risk of those populations.

  1. 40 CFR 421.252 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... silver smelted Lead 0.546 0.260 Mercury 0.325 0.130 Silver 0.533 0.221 Zinc 1.898 0.793 Gold 0.130 Oil... monthly average mg/troy ounce of silver reduced in solution Lead 0.168 0.080 Mercury 0.100 0.040 Silver 0... property Maximum for any 1 day Maximum for monthly average mg/troy ounce of gold refined electrolytically...

  2. Application of granulated lead-zinc slag in concrete as an opportunity to save natural resources

    NASA Astrophysics Data System (ADS)

    Alwaeli, Mohamed

    2013-02-01

    The last decades marked a period of growth and prosperity in construction industry which involves the use of natural resources. This growth is jeopardized by the lack of natural resources that are available. On the other hand there has been rapid increase in the industrial waste production. Most of the waste do not find any effective use and cause a waste disposal crisis, thereby contributing to health and environmental problems. Recycling of industrial waste as aggregate is thus a logical option to manage this problem. The paper reports on some experimental results obtained from the production of concretes containing granulated slag of lead and zinc industry as sand replacement mixed in different proportions. Granulated slag is substituted for raw sand, partly or totally. Ratios of 25%, 50%, 75% and 100% by weight of sand are used. The effects of granulated lead-zinc slag (GLZS) as sand replacement material on the compressive strength and gamma radiation attenuation properties of concrete are investigated and analyzed. Then, these properties are compared with those of ordinary concrete. The results showed that replacement material have some effects on the compressive strength and gamma radiation properties of the concrete. The experimental results indicate that, the concrete mixed with GLZS as a sand replacement have better strength. Concerning the absorption properties for gamma radiation the data show that the addition of GLZS resulted in an increase of the attenuation of gamma radiation. Consequently, these concretes could be used for construction of shields protecting personnel who work in laboratories where radiation is used. Additionally, the thickness of the concrete with GLZS was calculated and compared with ordinary concrete.

  3. EDITORIAL: Mercury-free discharges for lighting

    NASA Astrophysics Data System (ADS)

    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

  4. Statistical assessment of a sampling pattern for evaluation of changes in mercury and zinc concentrations in Patella coerulea

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Puel, D.; Zsuerger, N.; Breittmayer, J.P.

    1987-04-01

    The validity and representativeness of sampling, whether in temporal or in geographic terms, are always a problematical aspect of the evaluation of metal pollution in coastal sea water. Numerous field studies have underscored the great variety in metal levels in a given site, even in the very short term. The choice of sedentary test species disposes of the variation factor associated with those that move from place to place. Because they are ubiquitous and easy to collect, mollusks have very often been used for this purpose. This is particularly true of the mussel and the oyster because they are eatenmore » by man. The limpet (Patella) is a primary herbivore consumer and would seem an equally elective test organism. Its very localized feeding habits (grazing the algae colonizing the rocks where it lives) are less prone to sudden changes than those of the filtering mollusks. Indeed, it has already been employed in campaigns evaluating pollution by hydrocarbons and metals. To be able to compare several areas in this way, however, or follow their progress over the course of time, it is essential to work out a representative sampling plan. This paper reports an investigation of this aspect of the question with regard to two metals: mercury, which is toxic and plays no part in any natural metabolic process, and zinc, a cation required in weak concentrations by certain enzyme systems.« less

  5. Toxicity of sediments from lead-zinc mining areas to juvenile freshwater mussels (Lampsilis siliquoidea) compared to standard test organisms

    USGS Publications Warehouse

    Besser, John M.; Ingersoll, Christopher G.; Brumbaugh, William G.; Kemble, Nile E.; May, Thomas W.; Wang, Ning; MacDonald, Donald D.; Roberts, Andrew D.

    2015-01-01

    Sediment toxicity tests compared chronic effects on survival, growth, and biomass of juvenile freshwater mussels (28-d exposures with Lampsilis siliquoidea) to the responses of standard test organisms—amphipods (28-d exposures with Hyalella azteca) and midges (10-d exposures with Chironomus dilutus)—in sediments from 2 lead–zinc mining areas: the Tri-State Mining District and Southeast Missouri Mining District. Mussel tests were conducted in sediments sieved to <0.25 mm to facilitate recovery of juvenile mussels (2–4 mo old). Sediments were contaminated primarily with lead, zinc, and cadmium, with greater zinc and cadmium concentrations in Tri-State sediments and greater lead concentrations in southeast Missouri sediments. The frequency of highly toxic responses (reduced 10% or more relative to reference sites) in Tri-State sediments was greatest for amphipod survival (25% of samples), midge biomass (20%), and mussel survival (14%). In southeast Missouri sediments, the frequency of highly toxic samples was greatest for mussel biomass (25%) and amphipod biomass (13%). Thresholds for metal toxicity to mussels, expressed as hazard quotients based on probable effect concentrations, were lower for southeast Missouri sediments than for Tri-State sediments. Southeast Missouri sites with toxic sediments had 2 or fewer live mussel taxa in a concurrent mussel population survey, compared with 7 to 26 taxa at reference sites. These results demonstrate that sediment toxicity tests with juvenile mussels can be conducted reliably by modifying existing standard methods; that the sensitivity of mussels to metals can be similar to or greater than standard test organisms; and that responses of mussels in laboratory toxicity tests are consistent with effects on wild mussel populations.

  6. Methyl Mercury Production In Tropical Hydromorphic Soils: Impact Of Gold Mining.

    NASA Astrophysics Data System (ADS)

    Guedron, S.; Charlet, L.; Harris, J.; Grimaldi, M.; Cossa, D.

    2007-12-01

    Artisanal alluvial gold mining is important in many tropical developing countries and several million people are involved worldwide. The dominant use of mercury for gold amalgamation in this activity leads to mercury accumulation in soils, to sediment contamination and to methyl mercury (MMHg) bioaccumulation along the food chain. In this presentation we will present recent data on methyl mercury production in hydromorphic soils and tailing ponds from a former gold mining area located in French Guiana (South America). Comparison of specific fluxes between a pristine sub watershed and the contaminated watershed shows that former mining activities lead to a large enhancement of dissolved and particulate MMHg emissions at least by a factor of 4 and 6, respectively. MMHg production was identified in sediments from tailing ponds and in surrounding hydromorphic soils. Moreover, interstitial soil water and tailing pond water profiles sampled in an experimental tailing pond demonstrate the presence of a large MMHg production in the suboxic areas. Both tailing ponds and hydromorphic soils present geochemical conditions that are favorable to bacterial mercury methylation (high soil Hg content, high aqueous ferric iron and dissolved organic carbon concentrations). Although sulfate-reducing bacteria have been described as being the principal mercury methylating bacteria, the positive correlation between dissolved MMHg and ferrous iron concentrations argue for a significant role of iron-reducing bacteria. Identifications by sequencing fragments of 16S rRNA from total soil DNA support these interpretations. This study demonstrates that current and past artisanal gold mining in the tropics lead to methyl mercury production in contaminated areas. As artisanal activities are increasing with increasing gold prices, the bio- magnification of methyl mercury in fish presents an increasing threat to local populations whose diet relies on fish consumption.

  7. Radioactive zinc ( sup 65 Zn), zinc, cadmium, and mercury in the Pacific Hake, Merluccius productus (Ayres), off the West Coast of the United States

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Naidu, J.R.

    1974-06-01

    The Pacific Hake, Merluccius productus (Ayers) was used to monitor the waters off Puget Sound and the West Coast of the US for zinc(Zn), cadmium(Cd), mercury(Hg) and {sup 65}Zn. The Columbia River is not the source of Zn, Cd or Hg contamination, but is the source of {sup 65}Zn, with the concentration in the Hake reflecting the position of the Columbia River plume. Zn and Cd accumulation in the Hake were fit to the equation Y=B{sub 1}+B{sub 2}e{sup B}{sub 3}X where Y is the concentration of the element and X is the length or weight of the fish. Biological attributesmore » were assigned to the other parameters as follows: B{sub 1} is the asymptotic value for Zn or Cd at chemical maturity; B{sub 2} is the location of the curve with respect to the length or weight of the fish; and B{sub 3} is a constant pertaining to the rate of change of Zn or Cd. Although Zn, Cd and Hg are all Group 2B elements, only the concentrations of Zn and Cd were correlated for all locations; Hg concentrations varied as a function of location. Zn and Cd concentrations increase with fish size and approach an asymptotic value at maturity, while Hg concentrations were linear and the slope is a function of sampling location. Zn and Cd levels are regulated in the adult, while Hg continues to increase with age. It may be significant that the age distribution of fish caught commercially coincides with the maximum concentration of Zn and Cd. 195 refs., 30 figs., 10 tabs. (MHB)« less

  8. EDTA chelation effects on urinary losses of cadmium, calcium, chromium, cobalt, copper, lead, magnesium, and zinc.

    PubMed

    Waters, R S; Bryden, N A; Patterson, K Y; Veillon, C; Anderson, R A

    2001-12-01

    The efficacy of a chelating agent in binding a given metal in a biological system depends on the binding constants of the chelator for the particular metals in the system, the concentration of the metals, and the presence and concentrations of other ligands competing for the metals in question. In this study, we make a comparison of the in vitro binding constants for the chelator, ethylenediaminetetraacetic acid, with the quantitative urinary excretion of the metals measured before and after EDTA infusion in 16 patients. There were significant increases in lead, zinc, cadmium, and calcium, and these increases roughly corresponded to the expected relative increases predicted by the EDTA-metal-binding constants as measured in vitro. There were no significant increases in urinary cobalt, chromium, or copper as a result of EDTA infusion. The actual increase in cobalt could be entirely attributed to the cobalt content of the cyanocobalamin that was added to the infusion. Although copper did increase in the post-EDTA specimens, the increase was not statistically significant. In the case of magnesium, there was a net retention of approximately 85% following chelation. These data demonstrate that EDTA chelation therapy results in significantly increased urinary losses of lead, zinc, cadmium, and calcium following EDTA chelation therapy. There were no significant changes in cobalt, chromium, or copper and a retention of magnesium. These effects are likely to have significant effects on nutrient concentrations and interactions and partially explain the clinical improvements seen in patients undergoing EDTA chelation therapy.

  9. [XANES study of lead speciation in duckweed].

    PubMed

    Chu, Bin-Bin; Luo, Li-Qiang; Xu, Tao; Yuan, Jing; Sun, Jian-Ling; Zeng, Yuan; Ma, Yan-Hong; Yi, Shan

    2012-07-01

    Qixiashan lead-zinc mine of Nanjing was one of the largest lead zinc deposits in East China Its exploitation has been over 50 years, and the environmental pollution has also been increasing. The lead concentration in the local environment was high, but lead migration and toxic mechanism has not been clear. Therefore, biogeochemistry research of the lead zinc mine was carried out. Using ICP-MS and Pb-L III edge XANES, lead concentration and speciation were analyzed respectively, and duckweed which can tolerate and enriched heavy metals was found in the pollution area. The results showed that the lead concentration of duckweed was 39.4 mg x kg(-1). XANES analysis and linear combination fit indicated that lead stearate and lead sulfide accounted for 65% and 36.9% respectively in the lead speciation of duckweed, suggesting that the main lead speciation of duckweed was sulfur-containing lead-organic acid.

  10. Ecological characterization of streams, and fish-tissue analysis for mercury and lead at selected locations, Fort Gordon, Georgia, June 1999 to May 2000

    USGS Publications Warehouse

    Gregory, M. Brian; Stamey, Timothy C.; Wellborn, John B.

    2001-01-01

    The U.S. Geological Survey, in cooperation with the Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Ga., documented the ecological condition of selected water-bodies on the Fort Gordon military installation from June 1999 to May 2000. This study includes stream-habitat assessments, aquatic invertebrate and fish-community surveys in selected stream reaches, and analyses of mercury and lead concentrations in largemouth bass (Micropterous salmoides) muscle tissue from three impoundments. Assessment surveys indicate lower habitat value scores in some streams draining the more developed areas on Fort Gordon. A small tributary to Butler Creek--which drains parking lots associated with military motor pools and other impervious surfaces--is characterized by moderate levels of bank erosion and excess sediment in the stream channel compared to reference sites. Four other stream reaches are more similar to reference streams in respect to habitat conditions. Invertebrate communities in streams draining these urbanized watersheds are inhabited by 13 to 16 taxa per reach; whereas, 23 and 33 taxa were collected from the two reference stream reaches. Measures of invertebrate abundance, taxa richness, Ephemeroptera, Plecoptera, and Tricoptera Index are lower in streams draining urbanized watersheds. Measures of community similarity also indicate differences between streams draining urbanized areas and reference streams. Streams draining developed areas on Fort Gordon are inhabited by 3 to 10 fish species and included more species regarded as tolerant of degraded water-quality conditions; whereas, the two reference stream reaches support 4 and 10 species, respectively, including one species considered intolerant of degraded water-quality conditions. Mercury was detected in all largemouth bass collected from three impoundments on Fort Gordon. Wet-weight mercury concentrations in fish tissue analyzed from all sites range from 0

  11. Constraining Modern and Historic Mercury Emissions From Gold Mining

    NASA Astrophysics Data System (ADS)

    Strode, S. A.; Jaeglé, L.; Selin, N. E.; Sunderland, E.

    2007-12-01

    Mercury emissions from both historic gold and silver mining and modern small-scale gold mining are highly uncertain. Historic mercury emissions can affect the modern atmosphere through reemission from land and ocean, and quantifying mercury emissions from historic gold and silver mining can help constrain modern mining sources. While estimates of mercury emissions during historic gold rushes exceed modern anthropogenic mercury emissions in North America, sediment records in many regions do not show a strong gold rush signal. We use the GEOS-Chem chemical transport model to determine the spatial footprint of mercury emissions from mining and compare model runs from gold rush periods to sediment and ice core records of historic mercury deposition. Based on records of gold and silver production, we include mercury emissions from North and South American mining of 1900 Mg/year in 1880, compared to modern global anthropogenic emissions of 3400 Mg/year. Including this large mining source in GEOS-Chem leads to an overestimate of the modeled 1880 to preindustrial enhancement ratio compared to the sediment core record. We conduct sensitivity studies to constrain the level of mercury emissions from modern and historic mining that is consistent with the deposition records for different regions.

  12. Relationship of lead, mercury, mirex, dichlorodiphenyldichloroethylene, hexachlorobenzene, and polychlorinated biphenyls to timing of menarche among Akwesasne Mohawk girls.

    PubMed

    Denham, Melinda; Schell, Lawrence M; Deane, Glenn; Gallo, Mia V; Ravenscroft, Julia; DeCaprio, Anthony P

    2005-02-01

    Children are commonly exposed at background levels to several ubiquitous environmental pollutants, such as lead and persistent organic pollutants, that have been linked to neurologic and endocrine effects. These effects have prompted concern about alterations in human reproductive development. Few studies have examined the effects of these toxicants on human sexual maturation at levels commonly found in the general population, and none has been able to examine multiple toxicant exposures. The aim of the current investigation was to examine the relationship between attainment of menarche and levels of 6 environmental pollutants to which children are commonly exposed at low levels, ie, dichlorodiphenyldichloroethylene (p,p'-DDE), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), mirex, lead, and mercury. This study was conducted with residents of the Akwesasne Mohawk Nation, a sovereign territory that spans the St Lawrence River and the boundaries of New York State and Ontario and Quebec, Canada. Since the 1950s, the St Lawrence River has been a site of substantial industrial development, and the Nation is currently adjacent to a US National Priority Superfund site. PCB, p,p'-DDE, HCB, and mirex levels exceeding the US Food and Drug Administration recommended tolerance limits for human consumption have been found in local animal species. The present analysis included 138 Akwesasne Mohawk Nation girls 10 to 16.9 years of age. Blood samples and sociodemographic data were collected by Akwesasne community members, without prior knowledge of participants' exposure status. Attainment of menses (menarche) was assessed as present or absent at the time of the interview. Congener-specific PCB analysis was available, and all 16 PCB congeners detected in >50% of the sample were included in analyses (International Union of Pure and Applied Chemistry numbers 52, 70, 74, 84, 87, 95, 99, 101 [+90], 105, 110, 118, 138 [+163 and 164], 149 [+123], 153, 180, and 187). Probit

  13. A macroinvertebrate assessment of Ozark streams located in lead-zinc mining areas of the Viburnum Trend in southeastern Missouri, USA

    USGS Publications Warehouse

    Poulton, Barry C.; Allert, Ann L.; Besser, John M.; Schmitt, Christopher J.; Brumbaugh, William G.; Fairchild, James F.

    2010-01-01

    The Viburnum Trend lead-zinc mining subdistrict is located in the southeast Missouri portion of the Ozark Plateau. In 2003 and 2004, we assessed the ecological effects of mining in several watersheds in the region. We included macroinvertebrate surveys, habitat assessments, and analysis of metals in sediment, pore water, and aquatic biota. Macroinvertebrates were sampled at 21 sites to determine aquatic life impairment status (full, partial, or nonsupport) and relative biotic condition scores. Macroinvertebrate biotic condition scores were significantly correlated with cadmium, nickel, lead, zinc, and specific conductance in 2003 (r = -0.61 to -0.68) and with cadmium, lead, and pore water toxic units in 2004 (r = -0.55 to -0.57). Reference sites were fully supporting of aquatic life and had the lowest metals concentrations and among the highest biotic condition scores in both years. Sites directly downstream from mining and related activities were partially supporting, with biotic condition scores 10% to 58% lower than reference sites. Sites located greater distances downstream from mining activities had intermediate scores and concentrations of metals. Results indicate that elevated concentrations of metals originating from mining activities were the underlying cause of aquatic life impairment in several of the streams studied. There was general concurrence among the adversely affected sites in how the various indicators responded to mining activities during the overall study.

  14. A Photoluminescence Study of the Changes Induced in the Zinc White Pigment by Formation of Zinc Complexes

    PubMed Central

    Artesani, Alessia; Gherardi, Francesca; Nevin, Austin; Valentini, Gianluca; Comelli, Daniela

    2017-01-01

    It is known that oil paintings containing zinc white are subject to rapid degradation. This is caused by the interaction between the active groups of binder and the metal ions of the pigment, which gives rise to the formation of new zinc complexes (metal soaps). Ongoing studies on zinc white paints have been limited to the chemical mechanisms that lead to the formation of zinc complexes. On the contrary, little is known of the photo-physical changes induced in the zinc oxide crystal structure following this interaction. Time-resolved photoluminescence spectroscopy has been applied to follow modifications in the luminescent zinc white pigment when mixed with binder. Significant changes in trap state photoluminescence emissions have been detected: the enhancement of a blue emission combined with a change of the decay kinetic of the well-known green emission. Complementary data from molecular analysis of paints using Fourier transform infrared spectroscopy confirms the formation of zinc carboxylates and corroborates the mechanism for zinc complexes formation. We support the hypothesis that zinc ions migrate into binder creating novel vacancies, affecting the photoluminescence intensity and lifetime properties of zinc oxide. Here, we further demonstrate the advantages of a time-resolved photoluminescence approach for studying defects in semiconductor pigments. PMID:28772700

  15. Mercury

    USGS Publications Warehouse

    Franson, J.C.

    1999-01-01

    Mercury has been used by humans for over 2,000 years and was associated with premature deaths of cinnabar (mercuric sulfide) miners as early as 700 B.C. More recent human poisonings have been related to agricultural and industrial uses of mercury. One of the best documented of these cases occurred in the 1950s in Minamata Bay, Japan, when mercury was discharged into the environment and accumulated in fish and shellfish used as human food. In addition to human poisonings, mercury poisoning or toxicosis has been identified in many other species.Mercury is sometimes used to recover gold from stream sediments, and it may pose hazards to wildlife if it is released to the environment during ore recovery. Fungicidal treatment of seeds with mercury was common in the 1950s and 1960s, but this agricultural practice has been largely halted in the Northern Hemisphere.

  16. Planet Mercury

    NASA Image and Video Library

    1999-06-12

    The first image of Mercury acquired by NASA's Mariner 10 in 1974. During its flight, Mariner 10's trajectory brought it behind the lighted hemisphere of Mercury, where this image was taken, in order to acquire important measurements with other instruments. This picture was acquired from a distance of 3,340,000 miles (5,380,000 km) from the surface of Mercury. The diameter of Mercury (3,031 miles; 4,878 km) is about 1/3 that of Earth. Images of Mercury were acquired in two steps, an inbound leg (images acquired before passing into Mercury's shadow) and an outbound leg (after exiting from Mercury's shadow). More than 2300 useful images of Mercury were taken, both moderate resolution (3-20 km/pixel) color and high resolution (better than 1 km/pixel) black and white coverage. http://photojournal.jpl.nasa.gov/catalog/PIA00437

  17. Planet Mercury

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Mariner 10's first image of Mercury acquired on March 24, 1974. During its flight, Mariner 10's trajectory brought it behind the lighted hemisphere of Mercury, where this image was taken, in order to acquire important measurements with other instruments.

    This picture was acquired from a distance of 3,340,000 miles (5,380,000 km) from the surface of Mercury. The diameter of Mercury (3,031 miles; 4,878 km) is about 1/3 that of Earth.

    Images of Mercury were acquired in two steps, an inbound leg (images acquired before passing into Mercury's shadow) and an outbound leg (after exiting from Mercury's shadow). More than 2300 useful images of Mercury were taken, both moderate resolution (3-20 km/pixel) color and high resolution (better than 1 km/pixel) black and white coverage.

  18. Determination of Zinc, Cadmium and Lead Bioavailability in Contaminated Soils at the Single-Cell Level by a Combination of Whole-Cell Biosensors and Flow Cytometry

    PubMed Central

    Hurdebise, Quentin; Tarayre, Cédric; Fischer, Christophe; Colinet, Gilles; Hiligsmann, Serge; Delvigne, Frank

    2015-01-01

    Zinc, lead and cadmium are metallic trace elements (MTEs) that are widespread in the environment and tend to accumulate in soils because of their low mobility and non-degradability. The purpose of this work is to evaluate the applicability of biosensors as tools able to provide data about the bioavailability of such MTEs in contaminated soils. Here, we tested the genetically-engineered strain Escherichia coli pPZntAgfp as a biosensor applicable to the detection of zinc, lead and cadmium by the biosynthesis of green fluorescent protein (GFP) accumulating inside the cells. Flow cytometry was used to investigate the fluorescence induced by the MTEs. A curvilinear response to zinc between 0 and 25 mg/L and another curvilinear response to cadmium between 0 and 1.5 mg/L were highlighted in liquid media, while lead did not produce exploitable results. The response relating to a Zn2+/Cd2+ ratio of 10 was further investigated. In these conditions, E. coli pPZntAgfp responded to cadmium only. Several contaminated soils with a Zn2+/Cd2+ ratio of 10 were analyzed with the biosensor, and the metallic concentrations were also measured by atomic absorption spectroscopy. Our results showed that E. coli pPZntAgfp could be used as a monitoring tool for contaminated soils being processed. PMID:25894939

  19. Associations of blood lead, cadmium, and mercury with estimated glomerular filtration rate in the Korean general population: Analysis of 2008-2010 Korean National Health and Nutrition Examination Survey data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Yangho; Lee, Byung-Kook, E-mail: bklee@sch.ac.kr

    Introduction: The objective of this study was to evaluate associations between blood lead, cadmium, and mercury levels with estimated glomerular filtration rate in a general population of South Korean adults. Methods: This was a cross-sectional study based on data obtained in the Korean National Health and Nutrition Examination Survey (KNHANES) (2008-2010). The final analytical sample consisted of 5924 participants. Estimated glomerular filtration rate (eGFR) was calculated using the MDRD Study equation as an indicator of glomerular function. Results: In multiple linear regression analysis of log2-transformed blood lead as a continuous variable on eGFR, after adjusting for covariates including cadmium andmore » mercury, the difference in eGFR levels associated with doubling of blood lead were -2.624 mL/min per 1.73 m Superscript-Two (95% CI: -3.803 to -1.445). In multiple linear regression analysis using quartiles of blood lead as the independent variable, the difference in eGFR levels comparing participants in the highest versus the lowest quartiles of blood lead was -3.835 mL/min per 1.73 m Superscript-Two (95% CI: -5.730 to -1.939). In a multiple linear regression analysis using blood cadmium and mercury, as continuous or categorical variables, as independent variables, neither metal was a significant predictor of eGFR. Odds ratios (ORs) and 95% CI values for reduced eGFR calculated for log2-transformed blood metals and quartiles of the three metals showed similar trends after adjustment for covariates. Discussion: In this large, representative sample of South Korean adults, elevated blood lead level was consistently associated with lower eGFR levels and with the prevalence of reduced eGFR even in blood lead levels below 10 {mu}g/dL. In conclusion, elevated blood lead level was associated with lower eGFR in a Korean general population, supporting the role of lead as a risk factor for chronic kidney disease.« less

  20. LabVIEW-based sequential-injection analysis system for the determination of trace metals by square-wave anodic and adsorptive stripping voltammetry on mercury-film electrodes.

    PubMed

    Economou, Anastasios; Voulgaropoulos, Anastasios

    2003-01-01

    The development of a dedicated automated sequential-injection analysis apparatus for anodic stripping voltammetry (ASV) and adsorptive stripping voltammetry (AdSV) is reported. The instrument comprised a peristaltic pump, a multiposition selector valve and a home-made potentiostat and used a mercury-film electrode as the working electrodes in a thin-layer electrochemical detector. Programming of the experimental sequence was performed in LabVIEW 5.1. The sequence of operations included formation of the mercury film, electrolytic or adsorptive accumulation of the analyte on the electrode surface, recording of the voltammetric current-potential response, and cleaning of the electrode. The stripping step was carried out by applying a square-wave (SW) potential-time excitation signal to the working electrode. The instrument allowed unattended operation since multiple-step sequences could be readily implemented through the purpose-built software. The utility of the analyser was tested for the determination of copper(II), cadmium(II), lead(II) and zinc(II) by SWASV and of nickel(II), cobalt(II) and uranium(VI) by SWAdSV.

  1. LabVIEW-based sequential-injection analysis system for the determination of trace metals by square-wave anodic and adsorptive stripping voltammetry on mercury-film electrodes

    PubMed Central

    Economou, Anastasios; Voulgaropoulos, Anastasios

    2003-01-01

    The development of a dedicated automated sequential-injection analysis apparatus for anodic stripping voltammetry (ASV) and adsorptive stripping voltammetry (AdSV) is reported. The instrument comprised a peristaltic pump, a multiposition selector valve and a home-made potentiostat and used a mercury-film electrode as the working electrodes in a thin-layer electrochemical detector. Programming of the experimental sequence was performed in LabVIEW 5.1. The sequence of operations included formation of the mercury film, electrolytic or adsorptive accumulation of the analyte on the electrode surface, recording of the voltammetric current-potential response, and cleaning of the electrode. The stripping step was carried out by applying a square-wave (SW) potential-time excitation signal to the working electrode. The instrument allowed unattended operation since multiple-step sequences could be readily implemented through the purpose-built software. The utility of the analyser was tested for the determination of copper(II), cadmium(II), lead(II) and zinc(II) by SWASV and of nickel(II), cobalt(II) and uranium(VI) by SWAdSV. PMID:18924623

  2. New General Relativistic Contribution to Mercury's Perihelion Advance

    NASA Astrophysics Data System (ADS)

    Will, Clifford M.

    2018-05-01

    We point out the existence of a new general relativistic contribution to the perihelion advance of Mercury that, while smaller than the contributions arising from the solar quadrupole moment and angular momentum, is 100 times larger than the second-post-Newtonian contribution. It arises in part from relativistic "crossterms" in the post-Newtonian equations of motion between Mercury's interaction with the Sun and with the other planets, and in part from an interaction between Mercury's motion and the gravitomagnetic field of the moving planets. At a few parts in 1 06 of the leading general relativistic precession of 42.98 arcseconds per century, these effects are likely to be detectable by the BepiColombo mission to place and track two orbiters around Mercury, scheduled for launch around 2018.

  3. New General Relativistic Contribution to Mercury's Perihelion Advance.

    PubMed

    Will, Clifford M

    2018-05-11

    We point out the existence of a new general relativistic contribution to the perihelion advance of Mercury that, while smaller than the contributions arising from the solar quadrupole moment and angular momentum, is 100 times larger than the second-post-Newtonian contribution. It arises in part from relativistic "crossterms" in the post-Newtonian equations of motion between Mercury's interaction with the Sun and with the other planets, and in part from an interaction between Mercury's motion and the gravitomagnetic field of the moving planets. At a few parts in 10^{6} of the leading general relativistic precession of 42.98 arcseconds per century, these effects are likely to be detectable by the BepiColombo mission to place and track two orbiters around Mercury, scheduled for launch around 2018.

  4. Exogenous Glutathione Enhances Mercury Tolerance by Inhibiting Mercury Entry into Plant Cells

    PubMed Central

    Kim, Yeon-Ok; Bae, Hyeun-Jong; Cho, Eunjin; Kang, Hunseung

    2017-01-01

    Despite the increasing understanding of the crucial roles of glutathione (GSH) in cellular defense against heavy metal stress as well as oxidative stress, little is known about the functional role of exogenous GSH in mercury (Hg) tolerance in plants. Here, we provide compelling evidence that GSH contributes to Hg tolerance in diverse plants. Exogenous GSH did not mitigate the toxicity of cadmium (Cd), copper (Cu), or zinc (Zn), whereas application of exogenous GSH significantly promoted Hg tolerance during seed germination and seedling growth of Arabidopsis thaliana, tobacco, and pepper. By contrast, addition of buthionine sulfoximine, an inhibitor of GSH biosynthesis, severely retarded seed germination and seedling growth of the plants in the presence of Hg. The effect of exogenous GSH on Hg specific tolerance was also evident in the presence of other heavy metals, such as Cd, Cu, and Zn, together with Hg. GSH treatment significantly decreased H2O2 and O2- levels and lipid peroxidation, but increased chlorophyll content in the presence of Hg. Importantly, GSH treatment resulted in significantly less accumulation of Hg in Arabidopsis plants, and thin layer chromatography and nuclear magnetic resonance analysis revealed that GSH had much stronger binding affinity to Hg than to Cd, Cu, or Zn, suggesting that tight binding of GSH to Hg impedes Hg uptake, leading to low Hg accumulation in plant cells. Collectively, the present findings reveal that GSH is a potent molecule capable of conferring Hg tolerance by inhibiting Hg accumulation in plants. PMID:28507557

  5. Effect of Nitrogen Oxides on Elemental Mercury Removal by Nanosized Mineral Sulfide.

    PubMed

    Li, Hailong; Zhu, Lei; Wang, Jun; Li, Liqing; Lee, Po-Heng; Feng, Yong; Shih, Kaimin

    2017-08-01

    Because of its large surface area, nanosized zinc sulfide (Nano-ZnS) has been demonstrated in a previous study to be efficient for removal of elemental mercury (Hg 0 ) from coal combustion flue gas. The excellent mercury adsorption performance of Nano-ZnS was found to be insusceptible to water vapor, sulfur dioxide, and hydrogen chloride. However, nitrogen oxides (NO X ) apparently inhibited mercury removal by Nano-ZnS; this finding was unlike those of many studies on the promotional effect of NO X on Hg 0 removal by other sorbents. The negative effect of NO X on Hg 0 adsorption over Nano-ZnS was systematically investigated in this study. Two mechanisms were identified as primarily responsible for the inhibitive effect of NO X on Hg 0 adsorption over Nano-ZnS: (1) active sulfur sites on Nano-ZnS were oxidized to inactive sulfate by NO X ; and (2) the chemisorbed mercury, i.e., HgS, was reduced to Hg 0 by NO X . This new insight into the role of NO X in Hg 0 adsorption over Nano-ZnS can help to optimize operating conditions, maximize Hg 0 adsorption, and facilitate the application of Nano-ZnS as a superior alternative to activated carbon for Hg 0 removal using existing particulate matter control devices in power plants.

  6. Mercury study report to Congress. Volume 4. Health effects of mercury and mercury compounds. Sab review draft

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schoeny, R.

    1996-06-01

    This volume of the draft Mercury Study Report to Congress summarizes the available information on human health effects and animal data for hazard identification and dose-response assessment for three forms of mercury: elemental mercury, mercury chloride (inorganic mercury), and methylmercury (organic mercury). Effects are summarized by endpoint. The risk assessment evaluates carcinogenicity, mutagenicity, developmental toxicity and general systemic toxicity of these chemical species of mercury. Toxicokinetics (absorption, distribution, metabolism and excretion) are described for each of the three mercury species. PBPK models are described, but not applied in risk assessment. Reference doses are calculated for inorganic and methylmercury; a referencemore » concentration for inhaled elemental mercury is provided. A quantitiative analysis of factors contributing to variability and uncertainty in the methylmercury RfD is provided in an appendix. Interations and sensitive populations are described.« less

  7. 40 CFR 437.15 - Pretreatment standards for existing sources (PSES).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS THE CENTRALIZED WASTE TREATMENT POINT SOURCE CATEGORY Metals Treatment..., cadmium, chromium, cobalt, copper, lead, mercury, nickel, silver, tin, titanium, vanadium, and zinc are...

  8. Effects of mining-associated lead and zinc soil contamination on native floristic quality.

    PubMed

    Struckhoff, Matthew A; Stroh, Esther D; Grabner, Keith W

    2013-04-15

    We assessed the quality of plant communities across a range of lead (Pb) and zinc (Zn) soil concentrations at a variety of sites associated with Pb mining in southeast Missouri, USA. In a novel application, two standard floristic quality measures, Mean Coefficient of Conservatism (Mean C) and Floristic Quality Index (FQI), were examined in relation to concentrations of Pb and Zn, soil nutrients, and other soil characteristics. Nonmetric Multidimensional Scaling and Regression Tree Analyses identified soil Pb and Zn concentrations as primary explanatory variables for plant community composition and indicated negative relationships between soil metals concentrations and both Mean C and FQI. Univariate regression also demonstrated significant negative relationships between metals concentrations and floristic quality. The negative effects of metals in native soils with otherwise relatively undisturbed conditions indicate that elevated soil metals concentrations adversely affect native floristic quality where no other human disturbance is evident. Published by Elsevier Ltd.

  9. Pyrolysis of Plants After Phytoremediation of Contaminated Soil with Lead, Cadmium and Zinc.

    PubMed

    Özkan, Aysun; Günkaya, Zerrin; Banar, Müfide

    2016-03-01

    The aim of this study was to remediate lead (Pb), cadmium (Cd) and zinc (Zn) from contaminated soil and stabilize to pyrolysis solid product. To accomplish this, phytoremediation of soil contaminated with Pb, Cd and Zn by different plants (sunflower, corn and rape) was performed with and without ethylenediaminetetraacetic acid (EDTA). According to phytoremediation results, rape was the most effective plant with 72 %, 76 % and 77 % removal efficiency for Pb, Cd and Zn, respectively. Also, EDTA addition had no significant effect on translocation of the metals from roots to stems. According to pyrolysis results, Pb, Cd and Zn in the contaminated plants were stabilized in the ash/char fraction. In addition, the solid product can be safely landfilled as inert waste since its toxicity leaching value is lower than the limit values given in the Turkish Regulation on Landfilling of Wastes.

  10. Effects of mining-associated lead and zinc soil contamination on native floristic quality

    USGS Publications Warehouse

    Struckhoff, Matthew A.; Stroh, Esther D.; Grabner, Keith W.

    2013-01-01

    We assessed the quality of plant communities across a range of lead (Pb) and zinc (Zn) soil concentrations at a variety of sites associated with Pb mining in southeast Missouri, USA. In a novel application, two standard floristic quality measures, Mean Coefficient of Conservatism (Mean C) and Floristic Quality Index (FQI), were examined in relation to concentrations of Pb and Zn, soil nutrients, and other soil characteristics. Nonmetric Multidimensional Scaling and Regression Tree Analyses identified soil Pb and Zn concentrations as primary explanatory variables for plant community composition and indicated negative relationships between soil metals concentrations and both Mean C and FQI. Univariate regression also demonstrated significant negative relationships between metals concentrations and floristic quality. The negative effects of metals in native soils with otherwise relatively undisturbed conditions indicate that elevated soil metals concentrations adversely affect native floristic quality where no other human disturbance is evident.

  11. Recovery of mercury from mercury compounds via electrolytic methods

    DOEpatents

    Grossman, Mark W.; George, William A.

    1991-01-01

    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.

  12. Recovery of mercury from mercury compounds via electrolytic methods

    DOEpatents

    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.

  13. Recovery of mercury from mercury compounds via electrolytic methods

    DOEpatents

    Grossman, Mark W.; George, William A.

    1989-01-01

    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.

  14. Recovery of mercury from mercury compounds via electrolytic methods

    DOEpatents

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

    1991-06-18

    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. 3 figures.

  15. Recovery of mercury from mercury compounds via electrolytic methods

    DOEpatents

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

    1989-11-07

    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. 3 figs.

  16. Investigate of atmospheric arsenic, cadmium, chromium, lead, and mercury levels in moss species found around Zilkale, by EDXRF Spectrometry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akçay, Nilay, E-mail: nilay.akcay@erdogan.edu.tr; Batan, Nevzat, E-mail: nbatan@ktu.edu.tr; Çinar, Yunus, E-mail: yunus.cinar@erdogan.edu.tr

    Zilkale is a castle located in Fırtına Valley and it is one of the most important historical structures in Çamlihemşin district of Rize Province in the Black Sea Region of Turkey. The castle surrounded by very high mountains that poke up into the clouds, and it rains here all year round. Tourism businesses or industrial plants are not so much there yet. In recent years, Zilkale region has begun the attract tourist, people on treaking holidays in the Kaçkar. But many domestic and foreign tourists come to this region by own car or tour buses. The aim of this studymore » is to investigate the atmospheric concentrations of arsenic, cadmium, chromium, lead, and mercury levels in five different moss species collected around Zilkale by using Energy Dispersive X-ray Fluorescence (EDXRF) Spectrometry. The average concentrations of heavy metals in moss samples ranged from 0.79-4.63 ppm for arsenic, 54.47-143.39 ppm for chromium, 39.97-81.03 ppm for lead. The values of cadmium and mercury were found below the detection limit. This study has shown that Hypnum cupressiforme, Abietinella abietina, Rhytidium rugosum, Plagiomnium undulate, and Thuidium tamariscinum samples collected around Zilkale were used to assess the potential contamination of atmospheric As, Cd, Cr, Pb, Hg contamination in the region and made important contributions toward the understanding of atmospheric As, Cd, Cr, Pb, Hg baseline data can be used for identification of changes in the levels of these heavy metals in the studied area.« less

  17. Investigate of atmospheric arsenic, cadmium, chromium, lead, and mercury levels in moss species found around Zilkale, by EDXRF Spectrometry

    NASA Astrophysics Data System (ADS)

    Akçay, Nilay; Batan, Nevzat; Ćinar, Yunus

    2016-04-01

    Zilkale is a castle located in Fırtına Valley and it is one of the most important historical structures in Çamlihemşin district of Rize Province in the Black Sea Region of Turkey. The castle surrounded by very high mountains that poke up into the clouds, and it rains here all year round. Tourism businesses or industrial plants are not so much there yet. In recent years, Zilkale region has begun the attract tourist, people on treaking holidays in the Kaçkar. But many domestic and foreign tourists come to this region by own car or tour buses. The aim of this study is to investigate the atmospheric concentrations of arsenic, cadmium, chromium, lead, and mercury levels in five different moss species collected around Zilkale by using Energy Dispersive X-ray Fluorescence (EDXRF) Spectrometry. The average concentrations of heavy metals in moss samples ranged from 0.79-4.63 ppm for arsenic, 54.47-143.39 ppm for chromium, 39.97-81.03 ppm for lead. The values of cadmium and mercury were found below the detection limit. This study has shown that Hypnum cupressiforme, Abietinella abietina, Rhytidium rugosum, Plagiomnium undulate, and Thuidium tamariscinum samples collected around Zilkale were used to assess the potential contamination of atmospheric As, Cd, Cr, Pb, Hg contamination in the region and made important contributions toward the understanding of atmospheric As, Cd, Cr, Pb, Hg baseline data can be used for identification of changes in the levels of these heavy metals in the studied area.

  18. Effects of Different Zinc Species on Cellar Zinc Distribution, Cell Cycle, Apoptosis and Viability in MDAMB231 Cells.

    PubMed

    Wang, Yan-hong; Zhao, Wen-jie; Zheng, Wei-juan; Mao, Li; Lian, Hong-zhen; Hu, Xin; Hua, Zi-chun

    2016-03-01

    Intracellular metal elements exist in mammalian cells with the concentration range from picomoles per litre to micromoles per litre and play a considerable role in various biological procedures. Element provided by different species can influence the availability and distribution of the element in a cell and could lead to different biological effects on the cell's growth and function. Zinc as an abundant and widely distributed essential trace element, is involved in numerous and relevant physiological functions. Zinc homeostasis in cells, which is regulated by metallothioneins, zinc transporter/SLC30A, Zrt-/Irt-like proteins/SLC39A and metal-response element-binding transcription factor-1 (MTF-1), is crucial for normal cellular functioning. In this study, we investigated the influences of different zinc species, zinc sulphate, zinc gluconate and bacitracin zinc, which represented inorganic, organic and biological zinc species, respectively, on cell cycle, viability and apoptosis in MDAMB231 cells. It was found that the responses of cell cycle, apoptosis and death to different zinc species in MDAMB231 cells are different. Western blot analysis of the expression of several key proteins in regulating zinc-related transcription, cell cycle, apoptosis, including MTF-1, cyclin B1, cyclin D1, caspase-8 and caspase-9 in treated cells further confirmed the observed results on cell level.

  19. 49 CFR 173.164 - Mercury (metallic and articles containing mercury).

    Code of Federal Regulations, 2010 CFR

    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...

  20. 49 CFR 173.164 - Mercury (metallic and articles containing mercury).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 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...

  1. 49 CFR 173.164 - Mercury (metallic and articles containing mercury).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 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...

  2. 49 CFR 173.164 - Mercury (metallic and articles containing mercury).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 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...

  3. 49 CFR 173.164 - Mercury (metallic and articles containing mercury).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 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...

  4. Mining legacy across a wetland landscape: high mercury in Upper Peninsula (Michigan) rivers, lakes, and fish.

    PubMed

    Kerfoot, W Charles; Urban, Noel R; McDonald, Cory P; Zhang, Huanxin; Rossmann, Ronald; Perlinger, Judith A; Khan, Tanvir; Hendricks, Ashley; Priyadarshini, Mugdha; Bolstad, Morgan

    2018-04-25

    A geographic enigma is that present-day atmospheric deposition of mercury in the Upper Peninsula of Michigan is low (48%) and that regional industrial emissions have declined substantially (ca. 81% reduction) relative to downstate. Mercury levels should be declining. However, state (MDEQ) surveys of rivers and lakes revealed elevated total mercury (THg) in Upper Peninsula waters and sediment relative to downstate. Moreover, Western Upper Peninsula (WUP) fish possess higher methyl mercury (MeHg) levels than Northern Lower Peninsula (NLP) fish. A contributing explanation for elevated THg loading is that a century ago the Upper Peninsula was a major industrial region, centered on mining. Many regional ores (silver, copper, zinc, massive sulfides) contain mercury in part per million concentrations. Copper smelters and iron furnace-taconite operations broadcast mercury almost continuously for 140 years, whereas mills discharged tailings and old mine shafts leaked contaminated water. We show that mercury emissions from copper and iron operations were substantial (60-650 kg per year) and dispersed over relatively large areas. Moreover, lake sediments in the vicinity of mining operations have higher THg concentrations. Sediment profiles from the Keweenaw Waterway show that THg accumulation increased 50- to 400-fold above modern-day atmospheric deposition levels during active mining and smelting operations, with lingering MeHg effects. High MeHg concentrations are geographically correlated with low pH and dissolved organic carbon (DOC), a consequence of biogeochemical cycling in wetlands, characteristic of the Upper Peninsula. DOC can mobilize metals and elevate MeHg concentrations. We argue that mercury loading from mining is historically superimposed upon strong regional wetland effects, producing a combined elevation of both THg and MeHg in the Western Upper Peninsula.

  5. Highly effective removal of mercury and lead ions from wastewater by mercaptoamine-functionalised silica-coated magnetic nano-adsorbents: Behaviours and mechanisms

    NASA Astrophysics Data System (ADS)

    Bao, Shuangyou; Li, Kai; Ning, Ping; Peng, Jinhui; Jin, Xu; Tang, Lihong

    2017-01-01

    A novel hybrid material was fabricated using mercaptoamine-functionalised silica-coated magnetic nanoparticles (MAF-SCMNPs) and was effective in the extraction and recovery of mercury and lead ions from wastewater. The properties of this new magnetic material were explored using various characterisation and analysis methods. Adsorbent amounts, pH levels and initial concentrations were optimised to improve removal efficiency. Additionally, kinetics, thermodynamics and adsorption isotherms were investigated to determine the mechanism by which the fabricated MAF-SCMNPs adsorb heavy metal ions. The results revealed that MAF-SCMNPs were acid-resistant. Sorption likely occurred by chelation through the amine group and ion exchange between heavy metal ions and thiol functional groups on the nanoadsorbent surface. The equilibrium was attained within 120 min, and the adsorption kinetics showed pseudo-second-order (R2 > 0.99). The mercury and lead adsorption isotherms were in agreement with the Freundlich model, displaying maximum adsorption capacities of 355 and 292 mg/g, respectively. The maximum adsorptions took place at pH 5-6 and 6-7 for Hg(II) and Pb(II), respectively. The maximum adsorptions were observed at 10 mg and 12 mg adsorbent quantities for Hg(II) and Pb(II), respectively. The adsorption process was endothermic and spontaneous within the temperature range of 298-318 K. This work demonstrates a unique magnetic nano-adsorbent for the removal of Hg(II) and Pb(II) from wastewater.

  6. 40 CFR 437.24 - New source performance standards (NSPS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., TSS, arsenic, cadmium, chromium, cobalt, copper, lead, mercury, tin, zinc, butylbenzyl phthalate, carbazole, n-decane, bis(2-ethylhexyl) phthalate, fluoranthene, and n-octadecane are the same as the...

  7. 40 CFR 437.24 - New source performance standards (NSPS).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., TSS, arsenic, cadmium, chromium, cobalt, copper, lead, mercury, tin, zinc, butylbenzyl phthalate, carbazole, n-decane, bis(2-ethylhexyl) phthalate, fluoranthene, and n-octadecane are the same as the...

  8. Enhanced Color Mercury Map

    NASA Image and Video Library

    2017-12-08

    This colorful view of Mercury was produced by using images from the color base map imaging campaign during MESSENGER's primary mission. These colors are not what Mercury would look like to the human eye, but rather the colors enhance the chemical, mineralogical, and physical differences between the rocks that make up Mercury's surface. This specific color combination places the second principle component in the red channel, the first principle component in the green channel, and the ratio of the 430 nm/1000 nm filters in the blue channel. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. During the first two years of orbital operations, MESSENGER acquired over 150,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  9. Mercury recycling in the United States in 2000

    USGS Publications Warehouse

    Brooks, William E.; Matos, Grecia R.

    2005-01-01

    mercury is estimated because it is a low-volume commodity and its production, use, and disposal is difficult to track. The prices and volumes of each category of mercury-containing material may change dramatically from year to year. For example, the average price of mercury was approximately $150 per flask from 2000 until 2003 and then rose sharply to $650 per flask in fall 2004 and approximately $850 per flask in spring 2005. Since 1927, the common unit for measuring and pricing mercury has been the flask in order to conform to the system used at Almaden, Spain (Meyers, 1951). One flask weighs 34.5 kilograms, and 29 flasks of mercury are contained in a metric ton. In the United States, the chlorine-caustic soda industry, which is the leading end-user of elemental mercury, recycles most of its mercury in-plant as home scrap. Annual purchases of replacement mercury by the chlorine-caustic soda industry indicate that some mercury may be lost through evaporation to the environment, put into a landfill as industrial waste, or trapped within pipes in the plant. Impending closure of domestic and foreign mercury-cell chlorine-caustic soda plants and the shift to nonmercury technology for chlorine-caustic soda production could ultimately result in a significant volume of elemental mercury for recycling, sale, or storage. Globally, mercury is widely used in artisanal, or small-scale, gold mining. Most of that mercury is lost to the environment and is not recycled. The recycling rate for mercury was not available owing to insufficient data in 2000, and the efficiency of mercury recycling was estimated to be 62 percent.

  10. Small Mercury Relativity Orbiter

    NASA Technical Reports Server (NTRS)

    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.

  11. Lead, mercury, and cadmium exposure and attention deficit hyperactivity disorder in children

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Stephani; Arora, Monica; Fernandez, Cristina

    Background: There is limited research examining the relationship between lead (Pb) exposure and medically diagnosed attention deficit hyperactivity disorder (ADHD) in children. The role of mercury (Hg) and cadmium (Cd) exposures in ADHD development is even less clear. Objectives: To examine the relationship between Pb, Hg, and Cd and ADHD in children living inside and outside a Lead Investigation Area (LIA) of a former lead refinery in Omaha, NE. Methods: We carried out a case-control study with 71 currently medically diagnosed ADHD cases and 58 controls from a psychiatric clinic and a pediatric clinic inside and outside of the LIA.more » The participants were matched on age group (5–8, 9–12 years), sex, race (African American or Caucasians and others), and location (inside or outside LIA). We measured whole blood Pb, total Hg, and Cd using inductively coupled plasma mass spectrometry. Results: Inside the LIA, the 27 cases had blood Pb geometric mean (GM) 1.89 µg/dL and the 41 controls had 1.51 µg/dL. Outside the LIA, the 44 cases had blood Pb GM 1.02 µg/dL while the 17 controls had 0.97 µg/dL. After adjustment for matching variables and maternal smoking, socioeconomic status, and environmental tobacco exposure, each natural log unit blood Pb had an odds ratio of 2.52 with 95% confidence interval of 1.07–5.92. Stratification by the LIA indicated similar point estimate but wider CIs. No associations were observed for Hg or Cd. Conclusions: Postnatal Pb exposure may be associated with higher risk of clinical ADHD, but not the postnatal exposure to Hg or Cd. -- Highlights: • Blood Pb levels are associated with ADHD diagnosis in children. • No association was found between blood Cd or Hg levels and ADHD. • Children living close to hazardous waste site need to reduce metal exposure.« less

  12. Mercury Cavitation Phenomenon in Pulsed Spallation Neutron Sources

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Futakawa, Masatoshi; Naoe, Takashi; Kawai, Masayoshi

    2008-06-24

    Innovative researches will be performed at Materials and Life Science Experimental Facility in J-PARC, in which a mercury target system will be installed as MW-class pulse spallation neutron sources. Proton beams will be injected into mercury target to induce the spallation reaction. At the moment the intense proton beam hits the target, pressure waves are generated in the mercury because of the abrupt heat deposition. The pressure waves interact with the target vessel leading to negative pressure that may cause cavitation along the vessel wall. Localized impacts by micro-jets and/or shock waves which are caused by cavitation bubble collapse imposemore » pitting damage on the vessel wall. The pitting damage which degrades the structural integrity of target vessels is a crucial issue for high power mercury targets. Micro-gas-bubbles injection into mercury may be useful to mitigate the pressure wave and the pitting damage. The visualization of cavitation-bubble and gas-bubble collapse behaviors was carried out by using a high-speed video camera. The differences between them are recognized.« less

  13. Mercury

    NASA Astrophysics Data System (ADS)

    Taylor, G. J.; Scott, E. R. D.

    2003-12-01

    Mercury is an important part of the solar system puzzle, yet we know less about it than any other planet, except Pluto. Mercury is the smallest of the terrestrial planets (0.05 Earth masses) and the closest to the Sun. Its relatively high density (5.4 g cm -3) indicates that it has a large metallic core (˜3/4 of the planet's radius) compared to its silicate mantle and crust. The existence of a magnetic field implies that the metallic core is still partly molten. The surface is heavily cratered like the highlands of the Moon, but some areas are smooth and less cratered, possibly like the lunar maria (but not as dark). Its surface composition, as explained in the next section, appears to be low in FeO (only ˜3 wt.%), which implies that either its crust is anorthositic (Jeanloz et al., 1995) or its mantle is similarly low in FeO ( Robinson and Taylor, 2001).The proximity of Mercury to the Sun is particularly important. In one somewhat outmoded view of how the solar system formed, Mercury was assembled in the hottest region close to the Sun so that virtually all of the iron was in the metallic state, rather than oxidized to FeO (e.g., Lewis, 1972, 1974). If correct, Mercury ought to have relatively a low content of FeO. This hypothesis also predicts that Mercury should have high concentrations of refractory elements, such as calcium, aluminum, and thorium, and low concentrations of volatile elements, such as sodium and potassium, compared to the other terrestrial planets.Alternative hypotheses tell a much more nomadic and dramatic story of Mercury's birth. In one alternative view, wandering planetesimals that might have come from as far away as Mars or the inner asteroid belt accreted to form Mercury (Wetherill, 1994). This model predicts higher FeO and volatile elements than does the high-temperature model, and similar compositions among the terrestrial planets. The accretion process might have been accompanied by a monumental impact that stripped away much of the

  14. Study of samarium modified lead zirconate titanate and nickel zinc ferrite composite system

    NASA Astrophysics Data System (ADS)

    Rani, Rekha; Juneja, J. K.; Singh, Sangeeta; Raina, K. K.; Prakash, Chandra

    2015-03-01

    In the present work, composites of samarium substituted lead zirconate titanate and nickel zinc ferrite with compositional formula 0.95Pb1-3x/2 SmxZr0.65Ti0.35O3-0.05Ni0.8Zn0.2Fe2O4 (x=0, 0.01, 0.02 and 0.03) were prepared by the conventional solid state route. X-ray diffraction analysis was carried out to confirm the coexistence of individual phases. Microstructural study was done by using scanning electron microscope. Dielectric constant and loss were studied as a function of temperature and frequency. To study ferroelectric and magnetic properties of the composite samples, corresponding P-E and M-H hysteresis loops were recorded. Change in magnetic properties of electrically poled composite sample (x=0.02) was studied to confirm the magnetoelectric (ME) coupling. ME coefficient (dE/dH) of the samples (x=0 and 0.02) was measured as a function of DC magnetic field.

  15. Blood levels of lead, cadmium, and mercury in the Korean population: Results from the Second Korean National Human Exposure and Bio-monitoring Examination

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Son, Ji-Young; Lee, Jinheon; Paek, Domyung

    2009-08-15

    In Korea, there have been a number of efforts to measure levels of exposure to environmental pollutants among the population. This paper focuses on investigating the distribution of, extent of, and factors influencing the blood levels of lead, cadmium, and mercury in the Korean population, working from data obtained from the Second Korean National Human Exposure and Bio-monitoring Examination. To that end, blood metal concentrations were analyzed from a total of 2369 participants who were 18 years of age and older. The geometric mean concentrations and their 95% confidence intervals of metals in blood were found to be lead, 1.72more » {mu}g/dL (95% CI, 1.68-1.76); cadmium, 1.02 {mu}g/L (95% CI, 1.00-1.05); and mercury, 3.80 {mu}g/L (95% CI, 3.66-3.93). Regression analyses indicate that the levels of metals in the blood are mainly influenced by gender, age, and the education levels of the participants. Current smoking status is also found to be a significant factor for increasing both lead and cadmium levels. Although our study, as the first nationwide survey of exposure to environmental pollutants in Korea, has value on its own, it should be expanded and extended in order to provide information on environmental exposure pathways and to watch for changes in the level of exposure to environmental pollutants among the population.« less

  16. Mercury and Your Health

    MedlinePlus

    ... 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 ...

  17. Phytoremediation of Ionic and Methyl Mercury P

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meagher, Richard B.

    1999-06-01

    is that transgenic plants expressing the bacterial merB and merA genes will (a) remove mercury from polluted soil and water and (b) prevent methylmercury from entering the food chain. Our specific aims center on understanding the mechanisms by which plants process the various forms of mercury and volatilize or transpire mercury vapor. This information will allow us to improve the design of our current phytoremediation strategies. As an alternative to volatilizing mercury, we are using several new genes to construct plants that will hyperaccumulate mercury in above-ground tissues for later harvest. The Department of Energy's Oak Ridge National Laboratory and Brookhaven National Laboratory have sites with significant levels of mercury contamination that could be cleaned by applying the scientific discoveries and new phytoremediation technologies described in this proposal. The knowledge and expertise gained by engineering plants to hyperaccumulate mercury can be applied to the remediation of other heavy metals pollutants (e.g., arsenic, cesium, cadmium, chromium, lead, strontium, technetium, uranium) found at several DOE facilities.« less

  18. Predicting mercury in mallard ducklings from mercury in chorioallantoic membranes

    USGS Publications Warehouse

    Heinz, G.H.; Hoffman, D.J.

    2003-01-01

    Methylmercury has been suspected as a cause of impaired reproduction in wild birds, but the confounding effects of other environmental stressors has made it difficult to determine how much mercury in the eggs of these wild species is harmful. Even when a sample egg can be collected from the nest of a wild bird and the mercury concentration in that egg compared to the laboratory-derived thresholds for reproductive impairment, additional information on the mercury levels in other eggs from that nest would be helpful in determining whether harmful levels of mercury were present in the clutch. The measurement of mercury levels in chorioallantoic membranes offers a possible way to estimate how much mercury was in a chick that hatched from an egg, and also in the whole fresh egg itself. While an embryo is developing, wastes are collected in a sac called the chorioallantoic membranes, which often remain inside the eggshell and can be collected for contaminant analysis. We fed methylmercury to captive mallards to generate a broad range of mercury levels in eggs, allowed the eggs to hatch normally, and then compared mercury concentrations in the hatchling versus the chorioallantoic membranes left behind in the eggshell. When the data from eggs laid by mercury- treated females were expressed as common logarithms, a linear equation was created by which the concentration of mercury in a duckling could be predicted from the concentration of mercury in the chorioallantoic membranes from the same egg. Therefore, if it were not possible to collect a sample egg from a clutch of wild bird eggs, the collection of the chorioallantoic membranes could be substituted, and the mercury predicted to be in the chick or whole egg could be compared to the thresholds of mercury that have been shown to cause harm in controlled feeding studies with pheasants, chickens, and mallards.

  19. Mercury poisoning

    MedlinePlus

    ... of the lungs Medicine to remove mercury and heavy metals from the body INORGANIC MERCURY For inorganic mercury ... chap 98. Theobald JL, Mycyk MB. Iron and heavy metals. In: Walls RM, Hockberger RS, Gausche-Hill M, ...

  20. False Color View of Mercury

    NASA Image and Video Library

    2017-12-08

    This colorful view of Mercury was produced by using images from the color base map imaging campaign during MESSENGER's primary mission. These colors are not what Mercury would look like to the human eye, but rather the colors enhance the chemical, mineralogical, and physical differences between the rocks that make up Mercury's surface. To watch a movie of this colorful view of Mercury as a spinning globe go here: www.flickr.com/photos/gsfc/8497927473 Young crater rays, extending radially from fresh impact craters, appear light blue or white. Medium- and dark-blue areas are a geologic unit of Mercury's crust known as the "low-reflectance material", thought to be rich in a dark, opaque mineral. Tan areas are plains formed by eruption of highly fluid lavas. The giant Caloris basin is the large circular tan feature located just to the upper right of center of the image. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the key science questions that the MESSENGER mission is addressing. During the one-year primary mission, MESSENGER acquired 88,746 images and extensive other data sets. MESSENGER is now in a yearlong extended mission, during which plans call for the acquisition of more than 80,000 additional images to support MESSENGER's science goals. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on

  1. Smooth Plains in Mercury's North

    NASA Image and Video Library

    2017-12-08

    NASA acquired: March 29, 2011 As the MESSENGER spacecraft passed low over Mercury's north polar region, MDIS used its pivot to capture this image, showing terrain that had not been previously seen by spacecraft. The newly imaged surface is located in Mercury's north polar region, to the north of the bright, rayed crater Hokusai. Looking from the bottom of the image toward the top is looking southward, just as MDIS was doing when this image was acquired. This newly seen terrain shows craters with long shadows, as expected at this high northern latitude. Understanding the interiors of the craters in Mercury's polar regions and any ices they may contain is one of the main science goals of the MESSENGER mission. The long shadows also accentuate the topography of the surface, which includes a number of ridges that resemble those seen on the expansive smooth plains imaged during Mercury flyby 3. On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft ever to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook

  2. Beryllium, zinc and lead single crystals as a thermal neutron monochromators

    NASA Astrophysics Data System (ADS)

    Adib, M.; Habib, N.; Bashter, I. I.; Morcos, H. N.; El-Mesiry, M. S.; Mansy, M. S.

    2015-03-01

    The monochromatic features of Be, Zn and Pb single crystals are discussed in terms of orientation, mosaic spread, and thickness within the wavelength band from 0.04 up to 0.5 nm. A computer program MONO written in "FORTRAN-77", has been adapted to carry out the required calculations. Calculations show that a 5 mm thick of beryllium (HCP structure) single crystal cut along its (0 0 2) plane having 0.6° FWHM are the optimum parameters when it is used as a monochromator with high reflected neutron intensity from a thermal neutron flux. Furthermore, at wavelengths shorter than 0.16 nm it is free from the accompanying higher order ones. Zinc (HCP structure) has the same parameters, with intensity much less than the latter. The same features are seen with lead (FCC structure) cut along its (3 1 1) plane with less reflectivity than the former. However, Pb (3 1 1) is more preferable than others at neutron wavelengths ⩽ 0.1 nm, since the glancing angle (θ ∼ 20°) is more suitable to carry out diffraction experiments. For a cold neutron flux, the first-order neutrons reflected from beryllium is free from the higher orders up to 0.36 nm. While for Zn single crystal is up to 0.5 nm.

  3. Trace elements and organic compounds in streambed sediment and aquatic biota from the Sacramento River Basin, California, October and November 1995

    USGS Publications Warehouse

    MacCoy, Dorene E.; Domagalski, Joseph L.

    1999-01-01

    Elevated levels of trace elements and hydrophobic organic compounds were detected in streambed sediments and aquatic biota [Asiatic clam (Corbicula fluminea) or bottom-feeding fish] of the Sacramento River Basin, California, during October and November 1995. Trace elements detected included cadmium, copper, mercury, lead, and zinc. Elevated levels of cadmium, copper, and zinc in the upper Sacramento River are attributed to a mining land use, and elevated levels of zinc and lead in an urban stream, and possibly in the lower Sacramento River, are attributed to urban runoff processes. Elevated levels of mercury in streambed sediment are attributed to either past mercury mining or to the use of mercury in past gold mining operations. Mercury mining was an important land use within the Coast Ranges in the past and gold mining was an important land use of the Sierra Nevada in the past. Mercury was the only trace element found in elevated levels in the tissue of aquatic biota, and those levels also could be attributed to either mining or urban runoff. Hydrophobic organic compounds also were detected in streambed sediments and aquatic biota. The most frequently detected compounds were DDT and its breakdown products, dieldrin, oxychlordane, and toxaphene. Differences were found in the types of compounds detected at agricultural sites and the urban site. Although both types of sites had measurable concentrations of DDT or its breakdown products, the urban site also had measurable concentrations of pesticides used for household pest control. Few semivolatile compounds were detected in the streambed sediments of any site. The semivolatile compound p-cresol, a coal-tar derivative associated with road maintenance, was found in the highest concentration.

  4. The Nuclear Receptor HIZR-1 Uses Zinc as a Ligand to Mediate Homeostasis in Response to High Zinc

    PubMed Central

    Warnhoff, Kurt; Roh, Hyun C.; Kocsisova, Zuzana; Tan, Chieh-Hsiang; Morrison, Andrew; Croswell, Damari; Schneider, Daniel L.; Kornfeld, Kerry

    2017-01-01

    Nuclear receptors were originally defined as endocrine sensors in humans, leading to the identification of the nuclear receptor superfamily. Despite intensive efforts, most nuclear receptors have no known ligand, suggesting new ligand classes remain to be discovered. Furthermore, nuclear receptors are encoded in the genomes of primitive organisms that lack endocrine signaling, suggesting the primordial function may have been environmental sensing. Here we describe a novel Caenorhabditis elegans nuclear receptor, HIZR-1, that is a high zinc sensor in an animal and the master regulator of high zinc homeostasis. The essential micronutrient zinc acts as a HIZR-1 ligand, and activated HIZR-1 increases transcription of genes that promote zinc efflux and storage. The results identify zinc as the first inorganic molecule to function as a physiological ligand for a nuclear receptor and direct environmental sensing as a novel function of nuclear receptors. PMID:28095401

  5. Changing patterns in the use, recycling, and material substitution of mercury in the United States

    USGS Publications Warehouse

    Wilburn, David R.

    2013-01-01

    Environmental concerns have led to numerous regulations that have dramatically decreased the reported production and use of mercury in the United States since the 1980s. Government legislation and subsequent industry actions have led to increased collection of mercury-containing materials and the recovery of mercury through recycling. Mercury emissions have been reduced and effective alternatives to mercury products have been developed for many applications. This study updates and quantifies the changes in demand, supply, use, and material flow for mercury in various sectors in the United States that have taken place since 1996. Nearly all primary mercury produced in the United States is derived as a byproduct of processing of gold and silver ore in Nevada. Since 2001, annual production of mercury from gold and silver mining in Nevada has decreased by 22 percent overall because ore from greater depths containing low grade mercury is recovered, and mercury emissions from this source have decreased by 95 percent as a result of increased regulation and improved collection and suppression technology. The distribution of consumption of mercury in the United States has changed as a result of regulation (elimination of large-scale mercury use in the paint and battery sectors), reduction by consumers (decommissioning of mercury-cell chloralkali manufacturing capacity), and technological advances (improvements in dental, lighting, and wiring sectors). Mercury use in the chloralkali sector, the leading end-use sector in the United States in 1996, has declined by 98 percent from 136 metric tons (t) in 1996 to about 0.3 t in 2010 because of increased processing and recycling efficiencies and plant closures or conversion to other technologies. As plants were closed, mercury recovered from the infrastructure of decommissioned plants has been exported, making the United States a net exporter of mercury, even though no mercury has been produced as the primary product from mines in

  6. Surface plasmon resonance sensing detection of mercury and lead ions based on conducting polymer composite.

    PubMed

    Abdi, Mahnaz M; Abdullah, Luqman Chuah; Sadrolhosseini, Amir R; Mat Yunus, Wan Mahmood; Moksin, Mohd Maarof; Tahir, Paridah Md

    2011-01-01

    A new sensing area for a sensor based on surface plasmon resonance (SPR) was fabricated to detect trace amounts of mercury and lead ions. The gold surface used for SPR measurements were modified with polypyrrole-chitosan (PPy-CHI) conducting polymer composite. The polymer layer was deposited on the gold surface by electrodeposition. This optical sensor was used for monitoring toxic metal ions with and without sensitivity enhancement by chitosan in water samples. The higher amounts of resonance angle unit (ΔRU) were obtained for PPy-CHI film due to a specific binding of chitosan with Pb(2+) and Hg(2+) ions. The Pb(2+) ion bind to the polymer films most strongly, and the sensor was more sensitive to Pb(2+) compared to Hg(2+). The concentrations of ions in the parts per million range produced the changes in the SPR angle minimum in the region of 0.03 to 0.07. Data analysis was done by Matlab software using Fresnel formula for multilayer system.

  7. Mercury in traditional medicines: Is cinnabar toxicologically similar to common mercurials?

    PubMed Central

    Liu, Jie; Shi, Jing-Zheng; Yu, Li-Mei; Goyer, Robert A.; Waalkes, Michael P.

    2009-01-01

    Mercury is a major toxic metal ranking top in the Toxic Substances List. Cinnabar (contains mercury sulfide) has been used in traditional medicines for thousands years as an ingredient in various remedies, and 40 cinnabar-containing traditional medicines are still used today. Little is known about toxicology profiles or toxicokinetics of cinnabar and cinnabar-containing traditional medicines, and the high mercury content in these Chinese medicines raises justifiably escalations of public concern. This minireview searched the available database of cinnabar, compared cinnabar with common mercurials, such as mercury vapor, inorganic mercury, and organic mercury, and discusses differences in their bioavailability, disposition, and toxicity. The analysis showed that cinnabar is insoluble and poorly absorbed from the gastrointestinal tract. Absorbed mercury from cinnabar is mainly accumulated in kidney, resembling the disposition pattern of inorganic mercury. Heating cinnabar results in release of mercury vapor, which in turn can produce toxicity similar to inhalation of these vapors. The doses of cinnabar required to produce neurotoxicity are thousands 1000 times higher than methyl mercury. Following long-term use of cinnabar, renal dysfunction may occur. Dimercaprol and succimer are effective chelation therapies for general mercury intoxication including cinnabar. Pharmacology studies of cinnabar suggest sedative and hypnotic effects, but the therapeutic basis of cinnabar is still not clear. In summary, cinnabar is chemically inert with a relatively low toxic potential when taken orally. In risk assessment, cinnabar is less toxic than many other forms of mercury, but the rationale for its inclusion in traditional Chinese medicines remains to be fully justified. PMID:18445765

  8. Mercury concentration on Enhalus acoroides and Thalassia hemprichii at Seribu Islands

    NASA Astrophysics Data System (ADS)

    Suratno; Irawan, Andri

    2018-02-01

    Mercury is a toxic heavy metal element that can damage embryo development. Although this element is highly toxic, some human activities such as mining and industries are still using it. The uncontrolled usage of this element leads to pollution problem in the environment, which includes the seagrass ecosystem in the coastal area of Seribu Islands. For that, to gather more information about mercury pollution in the seagrass beds of these islands, the concentration of mercury (Hg) was measured in sediment, rhizomes, roots and leaves of two species of seagrass (Enhalus acoroides and Thalassia hemprichii) from Lancang Island, Pari Island and Panggang Island at Seribu Islands, Indonesia in April-May 2017. The highest concentration of mercury was found in sediment on Lancang Island. The concentration of mercury was significantly higher on leaves compare to on roots or rhizomes in E. acoroides on Lancang Island and Panggang Island. T. hemprichii accumulate mercury higher than E. acoroides on Lancang Island. Overall, mercury accumulation on both species ranges at 7.12 - 87.41 ug/kg dw and this shows that they have the potential as bio-indicator of mercury bio accumulation.

  9. 40 CFR 437.15 - Pretreatment standards for existing sources (PSES).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., cadmium, chromium, cobalt, copper, lead, mercury, nickel, silver, tin, titanium, vanadium, and zinc are the same as the corresponding limitation specified in § 437.11(a). (b) In-plant standards for cyanide...

  10. The Mercury Problem in Artisanal and Small‐Scale Gold Mining

    PubMed Central

    2018-01-01

    Abstract Mercury‐dependent artisanal and small‐scale gold mining (ASGM) is the largest source of mercury pollution on Earth. In this practice, elemental mercury is used to extract gold from ore as an amalgam. The amalgam is typically isolated by hand and then heated—often with a torch or over a stove—to distill the mercury and isolate the gold. Mercury release from tailings and vaporized mercury exceed 1000 tonnes each year from ASGM. The health effects on the miners are dire, with inhaled mercury leading to neurological damage and other health issues. The communities near these mines are also affected due to mercury contamination of water and soil and subsequent accumulation in food staples, such as fish—a major source of dietary protein in many ASGM regions. The risks to children are also substantial, with mercury emissions from ASGM resulting in both physical and mental disabilities and compromised development. Between 10 and 19 million people use mercury to mine for gold in more than 70 countries, making mercury pollution from ASGM a global issue. With the Minamata Convention on Mercury entering force this year, there is political motivation to help overcome the problem of mercury in ASGM. In this effort, chemists can play a central role. Here, the problem of mercury in ASGM is reviewed with a discussion on how the chemistry community can contribute solutions. Introducing portable and low‐cost mercury sensors, inexpensive and scalable remediation technologies, novel methods to prevent mercury uptake in fish and food crops, and efficient and easy‐to‐use mercury‐free mining techniques are all ways in which the chemistry community can help. To meet these challenges, it is critical that new technologies or techniques are low‐cost and adaptable to the remote and under‐resourced areas in which ASGM is most common. The problem of mercury pollution in ASGM is inherently a chemistry problem. We therefore encourage the chemistry community to

  11. hZIP1 zinc uptake transporter down regulation and zinc depletion in prostate cancer

    PubMed Central

    Franklin, Renty B; Feng, Pei; Milon, B; Desouki, Mohamed M; Singh, Keshav K; Kajdacsy-Balla, André; Bagasra, Omar; Costello, Leslie C

    2005-01-01

    glands is likely due to in situ gene silencing. These observations, coupled with the numerous and consistent reports of loss of zinc accumulation in malignant cells in prostate cancer, lead to the plausible proposal that down regulation of hZIP1 is a critical early event in the development prostate cancer. PMID:16153295

  12. AOCS operations preparation for the BepiColombo mission to mercury

    NASA Astrophysics Data System (ADS)

    Steiger, C.; Altay, A.; Montagnon, E.; Companys, V.

    2018-06-01

    The 2018 ESA/JAXA BepiColombo mission to Mercury features a complex modular design, with two scientific Mercury orbiters and a cruise module. The spacecraft (S/C) and mission design lead to a number of challenges for the attitude and orbit control system (AOCS), including electric propulsion usage during cruise to Mercury, AOCS capability to deal with several S/C configurations, and strict attitude constraints owing to the harsh thermal environment. This paper presents the activities for AOCS operations preparation by ESA/ESOC, covering the current preparation status as well as an outlook on upcoming activities before launch.

  13. Distribution and transfer of potentially toxic metal(loid)s in Juncus effusus from the indigenous zinc smelting area, northwest region of Guizhou Province, China.

    PubMed

    Peng, Yishu; Chen, Jun; Wei, Huairui; Li, Shibin; Jin, Tao; Yang, Ruidong

    2018-05-15

    We collected samples (i.e., the aerial parts and roots of Juncus effusus and their growth media) in the indigenous zinc smelting area in the northwest region of Guizhou Province, China, and we measured and analyzed potentially toxic metal(loid)s (arsenic, As; cadmium, Cd; chromium, Cr; copper, Cu; mercury, Hg; lead, Pb and zinc, Zn) in these samples. The results include the following: First, there is a high concentration of one or more potentially toxic metal(loid)s in the slag and surrounding soil in the research area. This situation might be caused by metal(loid) damage or contamination due to the circumstances. Additionally, Juncus effusus in the indigenous zinc smelting area are contaminated by some potentially toxic metal(loid)s; since they are used for Chinese medical materials, it is especially significant that their As, Cd and Pb concentrations are greater than their limited standard values. Finally, both the bioconcentration factors and transfer factors for most potentially toxic metal(loid)s in Juncus effusus are less than 1 in the study area. Therefore, we suggest that Juncus effusus could be used for phytostabilization or as a pioneer plant for phytoremediation of potentially toxic metal(loid)s because it has a tolerance and exclusion mechanism for these metal(loid)s in the research district. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Stimulation of erythrocyte phosphatidylserine exposure by mercury ions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eisele, Kerstin; Lang, Philipp A.; Kempe, Daniela S.

    2006-01-15

    The sequelae of mercury intoxication include induction of apoptosis. In nucleated cells, Hg{sup 2+}-induced apoptosis involves mitochondrial damage. The present study has been performed to elucidate effects of Hg{sup 2+} in erythrocytes which lack mitochondria but are able to undergo apoptosis-like alterations of the cell membrane. Previous studies have documented that activation of a Ca{sup 2+}-sensitive erythrocyte scramblase leads to exposure of phosphatidylserine at the erythrocyte surface, a typical feature of apoptotic cells. The erythrocyte scramblase is activated by osmotic shock, oxidative stress and/or energy depletion which increase cytosolic Ca{sup 2+} activity and/or activate a sphingomyelinase leading to formation ofmore » ceramide. Ceramide sensitizes the scramblase to Ca{sup 2+}. The present experiments explored the effect of Hg{sup 2+} ions on erythrocytes. Phosphatidylserine exposure after mercury treatment was estimated from annexin binding as determined in FACS analysis. Exposure to Hg{sup 2+} (1 {mu}M) indeed significantly increased annexin binding from 2.3 {+-} 0.5% (control condition) to 23 {+-} 6% (n = 6). This effect was paralleled by activation of a clotrimazole-sensitive K{sup +}-selective conductance as measured by patch-clamp recordings and by transient cell shrinkage. Further experiments revealed also an increase of ceramide formation by {approx}66% (n = 7) after challenge with mercury (1 {mu}M). In conclusion, mercury ions activate a clotrimazole-sensitive K{sup +}-selective conductance leading to transient cell shrinkage. Moreover, Hg{sup 2+} increases ceramide formation. The observed mechanisms could similarly participate in the triggering of apoptosis in nucleated cells by Hg{sup 2+}.« less

  15. Current approaches of the management of mercury poisoning: need of the hour

    PubMed Central

    2014-01-01

    Mercury poisoning cases have been reported in many parts of the world, resulting in many deaths every year. Mercury compounds are classified in different chemical types such as elemental, inorganic and organic forms. Long term exposure to mercury compounds from different sources e.g. water, food, soil and air lead to toxic effects on cardiovascular, pulmonary, urinary, gastrointestinal, neurological systems and skin. Mercury level can be measured in plasma, urine, feces and hair samples. Urinary concentration is a good indicator of poisoning of elemental and inorganic mercury, but organic mercury (e.g. methyl mercury) can be detected easily in feces. Gold nanoparticles (AuNPs) are a rapid, cheap and sensitive method for detection of thymine bound mercuric ions. Silver nanoparticles are used as a sensitive detector of low concentration Hg2+ ions in homogeneous aqueous solutions. Besides supportive therapy, British anti lewisite, dimercaprol (BAL), 2,3-dimercaptosuccinic acid (DMSA. succimer) and dimercaptopropanesulfoxid acid (DMPS) are currently used as chelating agents in mercury poisoning. Natural biologic scavengers such as algae, azolla and other aquatic plants possess the ability to uptake mercury traces from the environment. PMID:24888360

  16. Migration And Entrapment Of Mercury In The Subsurface

    NASA Astrophysics Data System (ADS)

    M, D.; Nambi, I. M.

    2009-12-01

    entrapment of mercury in the soil pores even in homogeneous porous medium system. Bond number (Bond number relates gravity and capillary forces) for mercury-water system was found to 2.5 times higher than PCE-water systems. Large density differences between mercury and water lead to high Bond number and thus less residual saturation. Capillary number (Capillary number relates viscous and capillary forces) was found to be less for mercury-water systems. Literature review unveils that low Capillary number does not influence non wetting residual saturation. But for high density mercury with natural infiltration, even low Capillary number influences residual saturation. With the alarming increase in number of mercury spill sites, results of this study showed a better understanding of the capillary entrapment phenomena and the extent of influence of each predominant force during displacement of highly dense mercury. The fundamental inputs to NAPL entrapment models were generated in this study for mercury for the first time. This data will be used to assess the distribution of mercury in contaminated sites and design suitable remedial alternatives.

  17. History of the mass of Mercury

    NASA Technical Reports Server (NTRS)

    Lyttleton, R. A.

    1980-01-01

    This paper discusses the calculation of the masses of planets, as a means to construct reliable tables for their positions. Emphasis is placed on the four inner planets and the moon, with additional consideration given to the history of the masses of Jupiter and Saturn. A smooth curve can be drawn with the logarithm of the masses of the earth, Venus, Mars, and the moon, but the point for Mercury lies substantially off the curve. An investigation of the material content, surface examination, and planet radius for the planets leads to a reexamination of the history of the value for the mass of Mercury.

  18. MERCURY RESEARCH STRATEGY.

    EPA Science Inventory

    The USEPA's ORD is pleased to announce the availability of its Mercury Research Strategy. This strategy guides ORD's mercury research program and covers the FY2001-2005 time frame. ORD will use it to prepare a multi-year mercury research implementation plan in 2001. The Mercury R...

  19. Zinc electrode and rechargeable zinc-air battery

    DOEpatents

    Ross, Jr., Philip N.

    1989-01-01

    An improved zinc electrode is disclosed for a rechargeable zinc-air battery comprising an outer frame and a porous foam electrode support within the frame which is treated prior to the deposition of zinc thereon to inhibit the formation of zinc dendrites on the external surface thereof. The outer frame is provided with passageways for circulating an alkaline electrolyte through the treated zinc-coated porous foam. A novel rechargeable zinc-air battery system is also disclosed which utilizes the improved zinc electrode and further includes an alkaline electrolyte within said battery circulating through the passageways in the zinc electrode and an external electrolyte circulation means which has an electrolyte reservoir external to the battery case including filter means to filter solids out of the electrolyte as it circulates to the external reservoir and pump means for recirculating electrolyte from the external reservoir to the zinc electrode.

  20. Pyrolysis Gas as a Renewable Reducing Agent for the Recycling of Zinc- and Lead-Bearing Residues: A Status Report

    NASA Astrophysics Data System (ADS)

    Pichler, C.; Antrekowitsch, J.

    2017-04-01

    The topic "Zero Waste" has been in existence for several years in the industry, and the metallurgical industry has also made efforts to reduce the amounts of residues occurring and have started several investigations to cut down on metallurgical by-products which have to be landfilled. Especially, the additional costs for CO2 emissions in different metallurgical steps have led to investigations into alternative carbon carriers. Charcoal has been identified to serve as an ideal substitute due its CO2-neutrality. For the applications of this renewable carbon carrier in metallurgical processes, charcoal production by means of a carbonization process needs to be optimized. As a by-product during the heating of agricultural wastes or wood by excluding air, pyrolysis gas occurs. Due to the existence of combustible compounds in this gas, an application as a reduction agent instead of fossil carbon carriers in metallurgy is possible. Based on the prevention of dumping metallurgical by-products, an investigation has been developed to treat zinc- and lead-containing materials. To realize this, a dedicated process concept has been designed and developed. As the main focuses, the usage of the pyrolysis gas from charcoal production for the Waelz kiln process and the recycling of zinc- and lead-containing Waelz slag, resulting from the processing of steel mill dust in a vertical retort, have to be mentioned. Within this research, the process concept was executed from laboratory-scale up to pilot-scale testing, described in this article.

  1. The Mercury Problem in Artisanal and Small-Scale Gold Mining.

    PubMed

    Esdaile, Louisa J; Chalker, Justin M

    2018-05-11

    Mercury-dependent artisanal and small-scale gold mining (ASGM) is the largest source of mercury pollution on Earth. In this practice, elemental mercury is used to extract gold from ore as an amalgam. The amalgam is typically isolated by hand and then heated-often with a torch or over a stove-to distill the mercury and isolate the gold. Mercury release from tailings and vaporized mercury exceed 1000 tonnes each year from ASGM. The health effects on the miners are dire, with inhaled mercury leading to neurological damage and other health issues. The communities near these mines are also affected due to mercury contamination of water and soil and subsequent accumulation in food staples, such as fish-a major source of dietary protein in many ASGM regions. The risks to children are also substantial, with mercury emissions from ASGM resulting in both physical and mental disabilities and compromised development. Between 10 and 19 million people use mercury to mine for gold in more than 70 countries, making mercury pollution from ASGM a global issue. With the Minamata Convention on Mercury entering force this year, there is political motivation to help overcome the problem of mercury in ASGM. In this effort, chemists can play a central role. Here, the problem of mercury in ASGM is reviewed with a discussion on how the chemistry community can contribute solutions. Introducing portable and low-cost mercury sensors, inexpensive and scalable remediation technologies, novel methods to prevent mercury uptake in fish and food crops, and efficient and easy-to-use mercury-free mining techniques are all ways in which the chemistry community can help. To meet these challenges, it is critical that new technologies or techniques are low-cost and adaptable to the remote and under-resourced areas in which ASGM is most common. The problem of mercury pollution in ASGM is inherently a chemistry problem. We therefore encourage the chemistry community to consider and address this issue that

  2. Mercury dynamics in a coastal plain watershed: insights from multiple models and empirical data

    EPA Science Inventory

    Interactions among atmospherically deposited mercury, abundant wetlands, and surface waters with elevated acidity and dissolved organic carbon (DOC) often lead to widespread mercury-related fish consumption advisories in the Coastal Plain of the southeastern United States (US). H...

  3. Isolation and identification of Aeromonas caviae strain KS-1 as TBTC- and lead-resistant estuarine bacteria.

    PubMed

    Shamim, Kashif; Naik, Milind Mohan; Pandey, Anju; Dubey, Santosh Kumar

    2013-06-01

    Tributyltin chloride (TBTC)- and lead-resistant estuarine bacterium from Mandovi estuary, Goa, India was isolated and identified as Aeromonas caviae strain KS-1 based on biochemical characteristics and FAME analysis. It tolerates TBTC and lead up to 1.0 and 1.4 mM, respectively, in the minimal salt medium (MSM) supplemented with 0.4 % glucose. Scanning electron microscopy clearly revealed a unique morphological pattern in the form of long inter-connected chains of bacterial cells on exposure to 1 mM TBTC, whereas cells remained unaltered in presence of 1.4 mM Pb(NO₃)₂ but significant biosorption of lead (8 %) on the cell surface of this isolate was clearly revealed by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. SDS-PAGE analysis of whole-cell proteins of this lead-resistant isolate interestingly demonstrated three lead-induced proteins with molecular mass of 15.7, 16.9 and 32.4 kDa, respectively, when bacterial cells were grown under the stress of 1.4 mM Pb (NO₃)₂. This clearly demonstrated their possible involvement exclusively in lead resistance. A. caviae strain KS-1 also showed tolerance to several other heavy metals, viz. zinc, cadmium, copper and mercury. Therefore, we can employ this TBTC and lead-resistant bacterial isolate for lead bioremediation and also for biomonitoring TBTC from lead and TBTC contaminated environment.

  4. 40 CFR 461.72 - Effluent limitations representing the degree of effluent reduction attainable by the application...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Metric units—mg/kg of Zinc English units—pounds per 1,000,000 pounds of Zinc Chromium 0.24 0.099 Mercury... Mercury 0.017 0.007 Silver 0.028 0.012 Zinc 0.099 0.042 Manganese 0.046 0.020 (3) Subpart G—Zinc Oxide... 3.90 Mercury 5.42 2.17 Silver 8.89 3.68 Zinc 31.64 13.22 Manganese 14.74 6.28 (4) Subpart G...

  5. Heavy metals in liquid pig manure in light of bacterial antimicrobial resistance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoelzel, Christina S., E-mail: Christina.Hoelzel@wzw.tum.de; Mueller, Christa; Harms, Katrin S.

    Heavy metals are regularly found in liquid pig manure, and might interact with bacterial antimicrobial resistance. Concentrations of heavy metals were determined by atomic spectroscopic methods in 305 pig manure samples and were connected to the phenotypic resistance of Escherichia coli (n=613) against 29 antimicrobial drugs. Concentrations of heavy metals (/kg dry matter) were 0.08-5.30 mg cadmium, 1.1-32.0 mg chrome, 22.4-3387.6 mg copper, <2.0-26.7 mg lead, <0.01-0.11 mg mercury, 3.1-97.3 mg nickel and 93.0-8239.0 mg zinc. Associated with the detection of copper and zinc, resistance rates against {beta}-lactams were significantly elevated. By contrast, the presence of mercury was significantly associatedmore » with low antimicrobial resistance rates of Escherichia coli against {beta}-lactams, aminoglycosides and other antibiotics. Effects of subinhibitory concentrations of mercury on bacterial resistance against penicillins, cephalosporins, aminoglycosides and doxycycline were also demonstrated in a laboratory trial. Antimicrobial resistance in the porcine microflora might be increased by copper and zinc. By contrast, the occurrence of mercury in the environment might, due to co-toxicity, act counter-selective against antimicrobial resistant strains.« less

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

    DOEpatents

    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.

  7. Zinc Levels in Left Ventricular Hypertrophy.

    PubMed

    Huang, Lei; Teng, Tianming; Bian, Bo; Yao, Wei; Yu, Xuefang; Wang, Zhuoqun; Xu, Zhelong; Sun, Yuemin

    2017-03-01

    Zinc is one of the most important trace elements in the body and zinc homeostasis plays a critical role in maintaining cellular structure and function. Zinc dyshomeostasis can lead to many diseases, such as cardiovascular disease. Our aim was to investigate whether there is a relationship between zinc and left ventricular hypertrophy (LVH). A total of 519 patients was enrolled and their serum zinc levels were measured in this study. We performed analyses on the relationship between zinc levels and LVH and the four LV geometry pattern patients: normal LV geometry, concentric remodeling, eccentric LVH, and concentric LVH. We performed further linear and multiple regression analyses to confirm the relationship between zinc and left ventricular mass (LVM), left ventricular mass index (LVMI), and relative wall thickness (RWT). Our data showed that zinc levels were 710.2 ± 243.0 μg/L in the control group and were 641.9 ± 215.2 μg/L in LVH patients. We observed that zinc levels were 715 ± 243.5 μg/L, 694.2 ± 242.7 μg/L, 643.7 ± 225.0 μg/L, and 638.7 ± 197.0 μg/L in normal LV geometry, concentric remodeling, eccentric LVH, and concentric LVH patients, respectively. We further found that there was a significant inverse linear relationship between zinc and LVM (p = 0.001) and LVMI (p = 0.000) but did not show a significant relationship with RWT (p = 0.561). Multiple regression analyses confirmed that the linear relationship between zinc and LVM and LVMI remained inversely significant. The present study revealed that serum zinc levels were significantly decreased in the LVH patients, especially in the eccentric LVH and concentric LVH patients. Furthermore, zinc levels were significantly inversely correlated with LVM and LVMI.

  8. Elevated Mercury Concentrations in Humans of Madre de Dios, Peru

    PubMed Central

    Ashe, Katy

    2012-01-01

    The enormous increase in practically unregulated mining in Madre de Dios Peru is leading to massive release of liquid elemental mercury to the environment. Rapidly increasing global prices for gold are causing a massive upsurge in artisanal mining in the Peruvian Amazon, considered to be one of the most biodiverse places on the planet. This study identifies the current levels of mercury in the human population, through identifying levels of total mercury in human hair in mining zones of Madre de Dios Department and in the nearby city of Puerto Maldonado. A regression analysis reveals that fish consumption, gender, and location of residence were significant indicators of mercury levels; while duration of residence and age had no significant relationship to mercury levels. Increased fish consumption levels were the strongest indicators of increased total mercury levels across the entire population. The levels of total mercury in hair was significantly (α = 0.05) higher in mining zones, than Puerto Maldonado. In both areas men had significantly higher levels than women, likely due to a difference in metabolism or varying levels of direct involvement in gold mining- a male predominated industry. This is the first study to show the health threat that mercury poses to this region, however further research needs to be done to gain a more refined understanding of the predominant routes of exposure in this population. PMID:22438911

  9. Elevated mercury concentrations in humans of Madre de Dios, Peru.

    PubMed

    Ashe, Katy

    2012-01-01

    The enormous increase in practically unregulated mining in Madre de Dios Peru is leading to massive release of liquid elemental mercury to the environment. Rapidly increasing global prices for gold are causing a massive upsurge in artisanal mining in the Peruvian Amazon, considered to be one of the most biodiverse places on the planet. This study identifies the current levels of mercury in the human population, through identifying levels of total mercury in human hair in mining zones of Madre de Dios Department and in the nearby city of Puerto Maldonado. A regression analysis reveals that fish consumption, gender, and location of residence were significant indicators of mercury levels; while duration of residence and age had no significant relationship to mercury levels. Increased fish consumption levels were the strongest indicators of increased total mercury levels across the entire population. The levels of total mercury in hair was significantly (α = 0.05) higher in mining zones, than Puerto Maldonado. In both areas men had significantly higher levels than women, likely due to a difference in metabolism or varying levels of direct involvement in gold mining- a male predominated industry. This is the first study to show the health threat that mercury poses to this region, however further research needs to be done to gain a more refined understanding of the predominant routes of exposure in this population.

  10. Characterisation of zinc delivery from a nipple shield delivery system using a breastfeeding simulation apparatus

    PubMed Central

    Bruggraber, Sylvaine F. A.; Gerrard, Stephen E.; Kendall, Richard A.; Tuleu, Catherine; Slater, Nigel K. H.

    2017-01-01

    Zinc delivery from a nipple shield delivery system (NSDS), a novel platform for administering medicines to infants during breastfeeding, was characterised using a breastfeeding simulation apparatus. In this study, human milk at flow rates and pressures physiologically representative of breastfeeding passed through the NSDS loaded with zinc-containing rapidly disintegrating tablets, resulting in release of zinc into the milk. Inductively coupled plasma optical emission spectrometry was used to detect the zinc released, using a method that does not require prior digestion of the samples and that could be applied in other zinc analysis studies in breast milk. Four different types of zinc-containing tablets with equal zinc load but varying excipient compositions were tested in the NSDS in vitro. Zinc release measured over 20 minutes ranged from 32–51% of the loaded dose. Total zinc release for sets tablets of the same composition but differing hardness were not significantly different from one another with P = 0.3598 and P = 0.1270 for two tested pairs using unpaired t tests with Welch’s correction. By the same test total zinc release from two sets of tablets having similar hardness but differing composition were also not significantly significant with P = 0.2634. Future zinc tablet composition and formulation optimisation could lead to zinc supplements and therapeutics with faster drug release, which could be administered with the NSDS during breastfeeding. The use of the NSDS to deliver zinc could then lead to treatment and prevention of some of the leading causes of child mortality, including diarrheal disease and pneumonia. PMID:28158283

  11. Characterisation of zinc delivery from a nipple shield delivery system using a breastfeeding simulation apparatus.

    PubMed

    Scheuerle, Rebekah L; Bruggraber, Sylvaine F A; Gerrard, Stephen E; Kendall, Richard A; Tuleu, Catherine; Slater, Nigel K H

    2017-01-01

    Zinc delivery from a nipple shield delivery system (NSDS), a novel platform for administering medicines to infants during breastfeeding, was characterised using a breastfeeding simulation apparatus. In this study, human milk at flow rates and pressures physiologically representative of breastfeeding passed through the NSDS loaded with zinc-containing rapidly disintegrating tablets, resulting in release of zinc into the milk. Inductively coupled plasma optical emission spectrometry was used to detect the zinc released, using a method that does not require prior digestion of the samples and that could be applied in other zinc analysis studies in breast milk. Four different types of zinc-containing tablets with equal zinc load but varying excipient compositions were tested in the NSDS in vitro. Zinc release measured over 20 minutes ranged from 32-51% of the loaded dose. Total zinc release for sets tablets of the same composition but differing hardness were not significantly different from one another with P = 0.3598 and P = 0.1270 for two tested pairs using unpaired t tests with Welch's correction. By the same test total zinc release from two sets of tablets having similar hardness but differing composition were also not significantly significant with P = 0.2634. Future zinc tablet composition and formulation optimisation could lead to zinc supplements and therapeutics with faster drug release, which could be administered with the NSDS during breastfeeding. The use of the NSDS to deliver zinc could then lead to treatment and prevention of some of the leading causes of child mortality, including diarrheal disease and pneumonia.

  12. LiZIP3 is a cellular zinc transporter that mediates the tightly regulated import of zinc in Leishmania infantum parasites

    PubMed Central

    Carvalho, Sandra; da Silva, Rosa Barreira; Shawki, Ali; Castro, Helena; Lamy, Márcia; Eide, David; Costa, Vítor; Mackenzie, Bryan; Tomás, Ana M.

    2016-01-01

    Summary Cellular zinc homeostasis ensures that the intracellular concentration of this element is kept within limits that enable its participation in critical physiological processes without exerting toxic effects. We report here the identification and characterization of the first mediator of zinc homeostasis in Leishmania infantum, LiZIP3, a member of the ZIP family of divalent metal-ion transporters. The zinc transporter activity of LiZIP3 was first disclosed by its capacity to rescue the growth of Saccharomyces cerevisiae strains deficient in zinc acquisition. Subsequent expression of LiZIP3 in Xenopus laevis oocytes was shown to stimulate the uptake of a broad range of metal ions, among which Zn2+ was the preferred LiZIP3 substrate (K0.5 ≈ 0.1 μM). Evidence that LiZIP3 functions as a zinc importer in L. infantum came from the observations that the protein locates to the cell membrane and that its overexpression leads to augmented zinc internalization. Importantly, expression and cell-surface location of LiZIP3 are lost when parasites face high zinc bioavailability. LiZIP3 decline in response to zinc is regulated at the mRNA level in a process involving (a) short-lived protein(s). Collectively, our data reveal that LiZIP3 enables L. infantum to acquire zinc in a highly regulated manner, hence contributing to zinc homeostasis. PMID:25644708

  13. A comprehensive study of Mercury and MESSENGER orbit determination

    NASA Astrophysics Data System (ADS)

    Genova, Antonio; Mazarico, Erwan; Goossens, Sander; Lemoine, Frank G.; Neumann, Gregory A.; Nicholas, Joseph B.; Rowlands, David D.; Smith, David E.; Zuber, Maria; Solomon, Sean C.

    2016-10-01

    The MErcury, Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft orbited the planet Mercury for more than 4 years. The probe started its science mission in orbit around Mercury on 18 March 2011. The Mercury Laser Altimeter (MLA) and radio science system were the instruments dedicated to geodetic observations of the topography, gravity field, orientation, and tides of Mercury. X-band radio-tracking range-rate data collected by the NASA Deep Space Network (DSN) allowed the determination of Mercury's gravity field to spherical harmonic degree and order 100, the planet's obliquity, and the Love number k2.The extensive range data acquired in orbit around Mercury during the science mission (from April 2011 to April 2015), and during the three flybys of the planet in 2008 and 2009, provide a powerful dataset for the investigation of Mercury's ephemeris. The proximity of Mercury's orbit to the Sun leads to a significant perihelion precession attributable to the gravitational flattening of the Sun (J2) and the Parameterized Post-Newtonian (PPN) coefficients γ and β, which describe the space curvature produced by a unit rest mass and the nonlinearity in superposition of gravity, respectively. Therefore, the estimation of Mercury's ephemeris can provide crucial information on the interior structure of the Sun and Einstein's general theory of relativity. However, the high correlation among J2, γ, and β complicates the combined recovery of these parameters, so additional assumptions are required, such as the Nordtvedt relationship η = 4β - γ - 3.We have modified our orbit determination software, GEODYN II, to enable the simultaneous integration of the spacecraft and central body trajectories. The combined estimation of the MESSENGER and Mercury orbits allowed us to determine a more accurate gravity field, orientation, and tides of Mercury, and the values of GM and J2 for the Sun, where G is the gravitational constant and M is the solar mass

  14. Mercury-impacted scrap metal: Source and nature of the mercury.

    PubMed

    Finster, Molly E; Raymond, Michelle R; Scofield, Marcienne A; Smith, Karen P

    2015-09-15

    The reuse and recycling of industrial solid wastes such as scrap metal is supported and encouraged both internationally and domestically, especially when such wastes can be used as substitutes for raw material. However, scrap metal processing facilities, such as mini-mills, have been identified as a source of mercury (Hg) emissions in the United States. This research aims to better define some of the key issues related to the source and nature of mercury in the scrap metal waste stream. Overall, it is difficult to pinpoint the key mercury sources feeding into scrap metal recycling facilities, quantify their associated mercury concentrations, or determine which chemical forms are most significant. Potential sources of mercury in scrap metal include mercury switches from discarded vehicles, electronic-based scrap from household appliances and related industrial systems, and Hg-impacted scrap metal from the oil and gas industry. The form of mercury associated with scrap metal varies and depends on the source type. The specific amount of mercury that can be adsorbed and retained by steel appears to be a function of both metallurgical and environmental factors. In general, the longer the steel is in contact with a fluid or condensate that contains measurable concentrations of elemental mercury, the greater the potential for mercury accumulation in that steel. Most mercury compounds are thermally unstable at elevated temperatures (i.e., above 350 °C). As such, the mercury associated with impacted scrap is expected to be volatilized out of the metal when it is heated during processing (e.g., shredding or torch cutting) or melted in a furnace. This release of fugitive gas (Hg vapor) and particulates, as well as Hg-impacted bag-house dust and control filters, could potentially pose an occupational exposure risk to workers at a scrap metal processing facility. Thus, identifying and characterizing the key sources of Hg-impacted scrap, and understanding the nature and extent

  15. Genetic causes and gene–nutrient interactions in mammalian zinc deficiencies: acrodermatitis enteropathica and transient neonatal zinc deficiency as examples.

    PubMed

    Kasana, Shakhenabat; Din, Jamila; Maret, Wolfgang

    2015-01-01

    Discovering genetic causes of zinc deficiency has been a remarkable scientific journey. It started with the description of a rare skin disease, its treatment with various agents, the successful therapy with zinc, and the identification of mutations in a zinc transporter causing the disease. The journey continues with defining the molecular and cellular pathways that lead to the symptoms caused by zinc deficiency. Remarkably, at least two zinc transporters from separate protein families are now known to be involved in the genetics of zinc deficiency. One is ZIP4, which is involved in intestinal zinc uptake. Its mutations can cause acrodermatitis enteropathica (AE) with autosomal recessive inheritance. The other one is ZnT2, the transporter responsible for supplying human milk with zinc. Mutations in this transporter cause transient neonatal zinc deficiency (TNZD) with symptoms similar to AE but with autosomal dominant inheritance. The two diseases can be distinguished in affected infants. AE is fatal if zinc is not supplied to the infant after weaning, whereas TNZD is a genetic defect of the mother limiting the supply of zinc in the milk, and therefore the infant usually will obtain enough zinc once weaned. Although these diseases are relatively rare, the full functional consequences of the numerous mutations in ZIP4 and ZnT2 and their interactions with dietary zinc are not known. In particular, it remains unexplored whether some mutations cause milder disease phenotypes or increase the risk for other diseases if dietary zinc requirements are not met or exceeded. Thus, it is not known whether widespread zinc deficiency in human populations is based primarily on a nutritional deficiency or determined by genetic factors as well. This consideration becomes even more significant with regard to mutations in the other 22 human zinc transporters, where associations with a range of diseases, including diabetes, heart disease, and mental illnesses have been observed

  16. Happy Little Crater on Mercury

    NASA Image and Video Library

    2017-12-08

    It looks like even the craters on Mercury have heard of Bob Ross! The central peaks of this complex crater have formed in such a way that it resembles a smiling face. This image is oriented so north is toward the bottom. This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the key science questions that the MESSENGER mission is addressing. During the one-year primary mission, MESSENGER acquired 88,746 images and extensive other data sets. MESSENGER is now in a yearlong extended mission, during which plans call for the acquisition of more than 80,000 additional images to support MESSENGER's science goals. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  17. Mercury contamination extraction

    DOEpatents

    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. Global Trends in Mercury Management

    PubMed Central

    Choi, Kyunghee

    2012-01-01

    The United Nations Environmental Program Governing Council has regulated mercury as a global pollutant since 2001 and has been preparing the mercury convention, which will have a strongly binding force through Global Mercury Assessment, Global Mercury Partnership Activities, and establishment of the Open-Ended Working Group on Mercury. The European Union maintains an inclusive strategy on risks and contamination of mercury, and has executed the Mercury Export Ban Act since December in 2010. The US Environmental Protection Agency established the Mercury Action Plan (1998) and the Mercury Roadmap (2006) and has proposed systematic mercury management methods to reduce the health risks posed by mercury exposure. Japan, which experienced Minamata disease, aims vigorously at perfection in mercury management in several ways. In Korea, the Ministry of Environment established the Comprehensive Plan and Countermeasures for Mercury Management to prepare for the mercury convention and to reduce risks of mercury to protect public health. PMID:23230466

  19. False Color View of Mercury

    NASA Image and Video Library

    2017-12-08

    This colorful view of Mercury was produced by using images from the color base map imaging campaign during MESSENGER's primary mission. These colors are not what Mercury would look like to the human eye, but rather the colors enhance the chemical, mineralogical, and physical differences between the rocks that make up Mercury's surface. Young crater rays, extending radially from fresh impact craters, appear light blue or white. Medium- and dark-blue areas are a geologic unit of Mercury's crust known as the "low-reflectance material", thought to be rich in a dark, opaque mineral. Tan areas are plains formed by eruption of highly fluid lavas. The crater in the upper right whose rays stretch across the planet is Hokusai. To watch a movie of this colorful view of Mercury as a spinning globe go here: www.flickr.com/photos/gsfc/8497927473 Young crater rays, extending radially from fresh impact craters, appear light blue or white. Medium- and dark-blue areas are a geologic unit of Mercury's crust known as the "low-reflectance material", thought to be rich in a dark, opaque mineral. Tan areas are plains formed by eruption of highly fluid lavas. The giant Caloris basin is the large circular tan feature located just to the upper right of center of the image. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the key science questions that the MESSENGER mission is addressing. During the one-year primary mission, MESSENGER acquired 88,746 images and extensive other data sets. MESSENGER is now in a yearlong extended mission, during which plans call for the acquisition of more than 80,000 additional images to support MESSENGER's science goals. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of

  20. Mercury Project

    NASA Image and Video Library

    1959-04-27

    Astronaut L. Gordon Cooper, Jr., one of the original seven astronauts for Mercury Project selected by NASA on April 27, 1959. The MA-9 mission, boosted by the Mercury-Atlas launch vehicle, was the last flight of the Mercury Project. The Faith 7 spacecraft orbited the Earth 22 times in 1-1/2 days.

  1. Got Mercury?

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

    Many lamps used in various spacecraft contain elemental mercury, which is efficiently absorbed through the lungs as a vapor. The liquid metal vaporizes slowly at room temperature, but may be completely vaporized when lamps are operating. Because current spacecraft environmental control systems are unable to remove mercury vapors, we considered short-term and long-term exposures. Using an existing study, we estimated mercury vapor releases from lamps that are not in operation during missions lasting less than or equal to 30 days; whereas we conservatively assumed complete vaporization from lamps that are operating or being used during missions lasing more than 30 days. Based on mercury toxicity, the Johnson Space Center's Toxicology Group recommends stringent safety controls and verifications for any hardware containing elemental mercury that could yield airborne mercury vapor concentrations greater than 0.1 mg/m3 in the total spacecraft atmosphere for exposures lasting less than or equal to 30 days, or concentrations greater than 0.01 mg/m3 for exposures lasting more than 30 days.

  2. Mercury elimination rates for adult northern pike Esox lucius: evidence for a sex effect

    USGS Publications Warehouse

    Madenjian, Charles P.; Blanchfield, Paul J.; Hrenchuk, Lee E.; Van Walleghem, Jillian L. A.

    2014-01-01

    We examined the effect of sex on mercury elimination in fish by monitoring isotope-enriched mercury concentrations in the muscle tissue of three adult female and three adult male northern pike Esox lucius, which had accumulated the isotope-enriched mercury via a whole-lake manipulation and were subsequently moved to a clean lake. Mercury elimination rates for female and male northern pike were estimated to be 0.00034 and 0.00073 day−1, respectively. Thus, males were capable of eliminating mercury at more than double the rate than that of females. To the best of our knowledge, our study represents the first documentation of mercury elimination rates varying between the sexes of fish. This sex difference in elimination rates should be taken into account when comparing mercury accumulation between the sexes of fish from the same population. Further, our findings should eventually lead to an improved understanding of mechanisms responsible for mercury elimination in vertebrates.

  3. Hemimorphite Ores: A Review of Processing Technologies for Zinc Extraction

    NASA Astrophysics Data System (ADS)

    Chen, Ailiang; Li, Mengchun; Qian, Zhen; Ma, Yutian; Che, Jianyong; Ma, Yalin

    2016-10-01

    With the gradual depletion of zinc sulfide ores, exploration of zinc oxide ores is becoming more and more important. Hemimorphite is a major zinc oxide ore, attracting much attention in the field of zinc metallurgy although it is not the major zinc mineral. This paper presents a critical review of the treatment for extraction of zinc with emphasis on flotation, pyrometallurgical and hydrometallurgical methods based on the properties of hemimorphite. The three-dimensional framework structure of hemimorphite with complex linkage of its structural units lead to difficult desilicification before extracting zinc in the many metallurgical technologies. It is found that the flotation method is generally effective in enriching zinc minerals from hemimorphite ores into a high-grade concentrate for recovery of zinc. Pure zinc can be produced from hemimorphite or/and willemite with a reducing reagent, like methane or carbon. Leaching reagents, such as acid and alkali, can break the complex structure of hemimorphite to release zinc in the leached solution without generation of silica gel in the hydrometallurgical process. For optimal zinc extraction, combing flotation with pyrometallurgical or hydrometallurgical methods may be required.

  4. "Wave" signal-smoothing and mercury-removing device for laser ablation quadrupole and multiple collector ICPMS analysis: application to lead isotope analysis.

    PubMed

    Hu, Zhaochu; Zhang, Wen; Liu, Yongsheng; Gao, Shan; Li, Ming; Zong, Keqing; Chen, Haihong; Hu, Shenghong

    2015-01-20

    A novel "wave" signal-smoothing and mercury-removing device has been developed for laser ablation quadrupole and multiple collector ICPMS analysis. With the wave stabilizer that has been developed, the signal stability was improved by a factor of 6.6-10 and no oscillation of the signal intensity was observed at a repetition rate of 1 Hz. Another advantage of the wave stabilizer is that the signal decay time is similar to that without the signal-smoothing device (increased by only 1-2 s for a signal decay of approximately 4 orders of magnitude). Most of the normalized elemental signals (relative to those without the stabilizer) lie within the range of 0.95-1.0 with the wave stabilizer. Thus, the wave stabilizer device does not significantly affect the aerosol transport efficiency. These findings indicate that this device is well-suited for routine optimization of ICPMS, as well as low repetition rate laser ablation analysis, which provides smaller elemental fractionation and better spatial resolution. With the wave signal-smoothing and mercury-removing device, the mercury gas background is reduced by 1 order of magnitude. More importantly, the (202)Hg signal intensity produced in the sulfide standard MASS-1 by laser ablation is reduced from 256 to 0.7 mV by the use of the wave signal-smoothing and mercury-removing device. This result suggests that the mercury is almost completely removed from the sample aerosol particles produced by laser ablation with the operation of the wave mercury-removing device. The wave mercury-removing device that we have designed is very important for Pb isotope ratio and accessory mineral U-Pb dating analysis, where removal of the mercury from the background gas and sample aerosol particles is highly desired. The wave signal-smoothing and mercury-removing device was applied successfully to the determination of the (206)Pb/(204)Pb isotope ratio in samples with low Pb content and/or high Hg content.

  5. Intracellular zinc flux causes reactive oxygen species mediated mitochondrial dysfunction leading to cell death in Leishmania donovani.

    PubMed

    Kumari, Anjali; Singh, Krishn Pratap; Mandal, Abhishek; Paswan, Ranjeet Kumar; Sinha, Preeti; Das, Pradeep; Ali, Vahab; Bimal, Sanjiva; Lal, Chandra Shekhar

    2017-01-01

    Leishmaniasis caused by Leishmania parasite is a global threat to public health and one of the most neglected tropical diseases. Therefore, the discovery of novel drug targets and effective drug is a major challenge and an important goal. Leishmania is an obligate intracellular parasite that alternates between sand fly and human host. To survive and establish infections, Leishmania parasites scavenge and internalize nutrients from the host. Nevertheless, host cells presents mechanism like nutrient restriction to inhibit microbial growth and control infection. Zinc is crucial for cellular growth and disruption in its homeostasis hinders growth and survival in many cells. However, little is known about the role of zinc in Leishmania growth and survival. In this study, the effect of zinc on the growth and survival of L.donovani was analyzed by both Zinc-depletion and Zinc-supplementation using Zinc-specific chelator N, N, N', N'-tetrakis (2-pyridylmethyl) ethylenediamine (TPEN) and Zinc Sulfate (ZnSO4). Treatment of parasites with TPEN rather than ZnSO4 had significantly affected the growth in a dose- and time-dependent manner. The pre-treatment of promastigotes with TPEN resulted into reduced host-parasite interaction as indicated by decreased association index. Zn depletion resulted into flux in intracellular labile Zn pool and increased in ROS generation correlated with decreased intracellular total thiol and retention of plasma membrane integrity without phosphatidylserine exposure in TPEN treated promastigotes. We also observed that TPEN-induced Zn depletion resulted into collapse of mitochondrial membrane potential which is associated with increase in cytosolic calcium and cytochrome-c. DNA fragmentation analysis showed increased DNA fragments in Zn-depleted cells. In summary, intracellular Zn depletion in the L. donovani promastigotes led to ROS-mediated caspase-independent mitochondrial dysfunction resulting into apoptosis-like cell death. Therefore, cellular

  6. Comparison of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers in bald eagle (Haliaeetus leucocephalus), and comparison with common eider (Somateria mollissima), glaucous-winged gull (Larus glaucescens), pigeon guillemot (Cepphus columba), and tufted puffin (Fratercula cirrhata) from the Aleutian Chain of Alaska

    PubMed Central

    Burger, Joanna; Gochfeld, Michael

    2014-01-01

    There is an abundance of field data for levels of metals from a range of places, but relatively few from the North Pacific Ocean and Bering Sea. In this paper we examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers from common eiders (Somateria mollissima), glaucous-winged gulls (Larus glaucescens), pigeon guillemots (Cepphus columba), tufted puffins (Fratercula cirrhata) and bald eagles (Haliaeetus leucocephalus) from the Aleutian Chain of Alaska. Our primary objective was to test the hypothesis that there are no trophic levels relationships for arsenic, cadmium, chromium, lead, manganese, mercury and selenium among these five species of birds breeding in the marine environment of the Aleutians. There were significant interspecific differences in all metal levels. As predicted bald eagles had the highest levels of arsenic, chromium, lead, and manganese, but puffins had the highest levels of selenium, and pigeon guillemot had higher levels of mercury than eagles (although the differences were not significant). Common eiders, at the lowest trophic level had the lowest levels of some metals (chromium, mercury and selenium). However, eiders had higher levels than all other species (except eagles) for arsenic, cadmium, lead, and manganese. Levels of lead were higher in breast than in wing feathers of bald eagles. Except for lead, there were no significant differences in metal levels in feathers of bald eagles nesting on Adak and Amchitka Island; lead was higher on Adak than Amchitka. Eagle chicks tended to have lower levels of manganese than older eagles. PMID:18521716

  7. Whole-ecosystem study shows rapid fish-mercury response to changes in mercury deposition

    USGS Publications Warehouse

    Harris, R.C.; Rudd, J.W.M.; Amyot, M.; Babiarz, Christopher L.; Beaty, K.G.; Blanchfield, P.J.; Bodaly, R.A.; Branfireun, B.A.; Gilmour, C.C.; Graydon, J.A.; Heyes, A.; Hintelmann, H.; Hurley, J.P.; Kelly, C.A.; Krabbenhoft, D.P.; Lindberg, S.E.; Mason, R.P.; Paterson, M.J.; Podemski, C.L.; Robinson, A.; Sandilands, K.A.; Southworthn, G.R.; St. Louis, V.L.; Tate, M.T.

    2007-01-01

    Methylmercury contamination of fisheries from centuries of industrial atmospheric emissions negatively impacts humans and wild-life worldwide. The response of fish methylmercury concentrations to changes in mercury deposition has been difficult to establish because sediments/soils contain large pools of historical contamination, and many factors in addition to deposition affect fish mercury. To test directly the response of fish contamination to changing mercury deposition, we conducted a whole-ecosystem experiment, increasing the mercury load to a lake and its watershed by the addition of enriched stable mercury isotopes. The isotopes allowed us to distinguish between experimentally applied mercury and mercury already present in the ecosystem and to examine bioaccumulation of mercury deposited to different parts of the watershed. Fish methylmercury concentrations responded rapidly to changes in mercury deposition over the first 3 years of study. Essentially all of the increase in fish methylmercury concentrations came from mercury deposited directly to the lake surface. In contrast, <1% of the mercury isotope deposited to the watershed was exported to the lake. Steady state was not reached within 3 years. Lake mercury isotope concentrations were still rising in lake biota, and watershed mercury isotope exports to the lake were increasing slowly. Therefore, we predict that mercury emissions reductions will yield rapid (years) reductions in fish methylmercury concentrations and will yield concomitant reductions in risk. However, a full response will be delayed by the gradual export of mercury stored in watersheds. The rate of response will vary among lakes depending on the relative surface areas of water and watershed. ?? 2007 by The National Academy of Sciences of the USA.

  8. Zinc Absorption by Young Adults from Supplemental Zinc Citrate Is Comparable with That from Zinc Gluconate and Higher than from Zinc Oxide123

    PubMed Central

    Wegmüller, Rita; Tay, Fabian; Zeder, Christophe; Brnić, Marica; Hurrell, Richard F.

    2014-01-01

    The water-soluble zinc salts gluconate, sulfate, and acetate are commonly used as supplements in tablet or syrup form to prevent zinc deficiency and to treat diarrhea in children in combination with oral rehydration. Zinc citrate is an alternative compound with high zinc content, slightly soluble in water, which has better sensory properties in syrups but no absorption data in humans. We used the double-isotope tracer method with 67Zn and 70Zn to measure zinc absorption from zinc citrate given as supplements containing 10 mg of zinc to 15 healthy adults without food and compared absorption with that from zinc gluconate and zinc oxide (insoluble in water) using a randomized, double-masked, 3-way crossover design. Median (IQR) fractional absorption of zinc from zinc citrate was 61.3% (56.6–71.0) and was not different from that from zinc gluconate with 60.9% (50.6–71.7). Absorption from zinc oxide at 49.9% (40.9–57.7) was significantly lower than from both other supplements (P < 0.01). Three participants had little or no absorption from zinc oxide. We conclude that zinc citrate, given as a supplement without food, is as well absorbed by healthy adults as zinc gluconate and may thus be a useful alternative for preventing zinc deficiency and treating diarrhea. The more insoluble zinc oxide is less well absorbed when given as a supplement without food and may be minimally absorbed by some individuals. This trial was registered at clinicaltrials.gov as NCT01576627. PMID:24259556

  9. Improved electrolyte for zinc-bromine flow batteries

    NASA Astrophysics Data System (ADS)

    Wu, M. C.; Zhao, T. S.; Wei, L.; Jiang, H. R.; Zhang, R. H.

    2018-04-01

    Conventional zinc bromide electrolytes offer low ionic conductivity and often trigger severe zinc dendrite growth in zinc-bromine flow batteries. Here we report an improved electrolyte modified with methanesulfonic acid, which not only improves the electrolyte conductivity but also ameliorates zinc dendrite. Experimental results also reveal that the kinetics and reversibility of Zn2+/Zn and Br2/Br- are improved in this modified electrolyte. Moreover, the battery's internal resistance is significantly reduced from 4.9 to 2.0 Ω cm2 after adding 1 M methanesulfonic acid, thus leading to an improved energy efficiency from 64% to 75% at a current density of 40 mA cm-2. More impressively, the battery is capable of delivering an energy efficiency of about 78% at a current density of as high as 80 mA cm-2 when the electrode is replaced by a thermally treated one. Additionally, zinc dendrite growth is found to be effectively suppressed in methanesulfonic acid supported media, which, as a result, enables the battery to be operated for 50 cycles without degradation, whereas the one without methanesulfonic acid suffers from significant decay after only 40 cycles, primarily due to severe zinc dendrite growth. These superior results indicate methanesulfonic acid is a promising supporting electrolyte for zinc-bromine flow batteries.

  10. 40 CFR 461.74 - Pretreatment standards for existing sources (PSES).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...,000 pounds of zinc Chromium 0.24 0.099 Mercury 0.14 0.055 Silver 0.23 0.093 Zinc 0.80 0.34 Manganese 0... of zinc Chromium 0.030 0.12 Mercury 0.017 0.006 Silver 0.028 0.012 Zinc 0.099 0.042 Manganese 0.046 0... Chromium 9.53 3.90 Mercury 5.42 2.17 Silver 8.89 3.68 Zinc 31.64 13.22 Manganese 14.74 6.28 (4) Subpart G...

  11. 40 CFR 461.74 - Pretreatment standards for existing sources (PSES).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...,000 pounds of zinc Chromium 0.24 0.099 Mercury 0.14 0.055 Silver 0.23 0.093 Zinc 0.80 0.34 Manganese 0... of zinc Chromium 0.030 0.12 Mercury 0.017 0.006 Silver 0.028 0.012 Zinc 0.099 0.042 Manganese 0.046 0... Chromium 9.53 3.90 Mercury 5.42 2.17 Silver 8.89 3.68 Zinc 31.64 13.22 Manganese 14.74 6.28 (4) Subpart G...

  12. 40 CFR 461.74 - Pretreatment standards for existing sources (PSES).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...,000 pounds of zinc Chromium 0.24 0.099 Mercury 0.14 0.055 Silver 0.23 0.093 Zinc 0.80 0.34 Manganese 0... of zinc Chromium 0.030 0.12 Mercury 0.017 0.006 Silver 0.028 0.012 Zinc 0.099 0.042 Manganese 0.046 0... Chromium 9.53 3.90 Mercury 5.42 2.17 Silver 8.89 3.68 Zinc 31.64 13.22 Manganese 14.74 6.28 (4) Subpart G...

  13. Peru Mercury Inventory 2006

    USGS Publications Warehouse

    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

  14. Mercury, Lead, Cadmium, Arsenic, Chromium and Selenium in Feathers of Shorebirds during Migrating through Delaware Bay, New Jersey: Comparing the 1990s and 2011/2012

    PubMed Central

    Burger, Joanna; Tsipoura, Nellie; Niles, Lawrence J.; Gochfeld, Michael; Dey, Amanda; Mizrahi, David

    2015-01-01

    Understanding temporal changes in contaminant levels in coastal environments requires comparing levels of contaminants from the same species from different time periods, particularly if species are declining. Several species of shorebirds migrating through Delaware Bay have declined from the 1980s to the present. To evaluate some contaminants as cause for the declines, we examine levels of mercury, lead, cadmium, arsenic, chromium and selenium in feathers of red knot (Calidris canutus, N = 46 individuals), semipalmated sandpiper (Calidris pusilla, N = 70) and sanderling (Calidris alba, N = 32) migrating through Delaware Bay, New Jersey, USA, from 1991 to 1992 (N = 40), 1995 (N = 28), and 2011–2012 (N = 80) to determine if levels have changed. We found: (1) arsenic, chromium, and lead increased in red knot and decreased in semipalmated sandpiper; (2) cadmium decreased in semipalmated sandpipers; (3) mercury decreased in red knot and sanderlings; (4) selenium decreased in red knot and increased in semipalmated sandpipers. In 2011/2012 there were significant interspecific differences for arsenic, mercury and selenium. Except for selenium, the element levels were well below levels reported for feathers of other species. The levels in feathers in red knots, sanderling, and semipalmated sandpipers from Delaware Bay in 2011/2012 were well below levels in feathers that are associated with effect levels, except for selenium. Selenium levels ranged from 3.0 µg·g−1 dry weight to 5.8 µg·g−1 (semipalmated sandpiper), within the range known to cause adverse effects, suggesting the need for further examination of selenium levels in birds. The levels of all elements were well below those reported for other marine species, except for selenium, which was near levels suggesting possible toxic effects. PMID:29056651

  15. Dietary phytate, zinc and hidden zinc deficiency.

    PubMed

    Sandstead, Harold H; Freeland-Graves, Jeanne H

    2014-10-01

    Epidemiological data suggest at least one in five humans are at risk of zinc deficiency. This is in large part because the phytate in cereals and legumes has not been removed during food preparation. Phytate, a potent indigestible ligand for zinc prevents it's absorption. Without knowledge of the frequency of consumption of foods rich in phytate, and foods rich in bioavailable zinc, the recognition of zinc deficiency early in the illness may be difficult. Plasma zinc is insensitive to early zinc deficiency. Serum ferritin concentration≤20μg/L is a potential indirect biomarker. Early effects of zinc deficiency are chemical, functional and may be "hidden". The clinical problem is illustrated by 2 studies that involved US Mexican-American children, and US premenopausal women. The children were consuming home diets that included traditional foods high in phytate. The premenopausal women were not eating red meat on a regular basis, and their consumption of phytate was mainly from bran breakfast cereals. In both studies the presence of zinc deficiency was proven by functional responses to controlled zinc treatment. In the children lean-mass, reasoning, and immunity were significantly affected. In the women memory, reasoning, and eye-hand coordination were significantly affected. A screening self-administered food frequency questionnaire for office might help caregiver's identify patients at risk of zinc deficiency. Copyright © 2014 Elsevier GmbH. All rights reserved.

  16. Effects of methyl mercury exposure on pancreatic beta cell development and function.

    PubMed

    Schumacher, Lauren; Abbott, Louise C

    2017-01-01

    Methyl mercury is an environmental contaminant of worldwide concern. Since the discovery of methyl mercury exposure due to eating contaminated fish as the underlying cause of the Minamata disaster, the scientific community has known about the sensitivity of the developing central nervous system to mercury toxicity. Warnings are given to pregnant women and young children to limit consumption of foods containing methyl mercury to protect the embryonic, fetal and postnatally developing central nervous system. However, evidence also suggests that exposure to methyl mercury or various forms of inorganic mercury may also affect development and function of other organs. Numerous reports indicate a worldwide increase in diabetes, particularly type 2 diabetes. Quite recently, methyl mercury has been shown to have adverse effects on pancreatic beta (β) cell development and function, resulting in insulin resistance and hyperglycemia and may even lead to the development of diabetes. This review discusses possible mechanisms by which methyl mercury exposure may adversely affect pancreatic β cell development and function, and the role that methyl mercury exposure may have in the reported worldwide increase in diabetes, particularly type 2 diabetes. While additional information is needed regarding associations between mercury exposure and specific mechanisms of the pathogenesis of diabetes in the human population, methyl mercury's adverse effects on the body's natural sources of antioxidants suggest that one possible therapeutic strategy could involve supplementation with antioxidants. Thus, it is important that additional investigation be undertaken into the role of methyl mercury exposure and reduced pancreatic β cell function. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  17. 700 years reconstruction of mercury and lead atmospheric deposition in the Pyrenees (NE Spain)

    NASA Astrophysics Data System (ADS)

    Corella, J. P.; Valero-Garcés, B. L.; Wang, F.; Martínez-Cortizas, A.; Cuevas, C. A.; Saiz-Lopez, A.

    2017-04-01

    Geochemical analyses in varved lake sediment cores (Lake Montcortès, Pre-Pyrenees) allowed reconstruction of mercury (Hg) and lead (Pb) atmospheric deposition over the past seven centuries in the Pyrenees (NE Spain). Accumulation Rates (AR) from the Middle Ages to the Industrial Period ranged from 2500 to 26130 μg m2.y-1 and 15-152 μg m2.y-1 for Pb and Hg respectively. Significant metal pollution started ca CE 1550 during a period of increased exploitation of ore resources in Spain. Colder and humid conditions in the Pyrenees during the Little Ice Age may have also favoured Hg and Pb atmospheric deposition in the lake. Therefore, the interplay between increased rainfall (wet deposition) and mining activities in the Iberian Peninsula has driven Hg and Pb AR during the Pre-industrial Period. More recently, the use of leaded gasoline in Europe in the mid-20th century may explain the highest Pb AR between CE 1953 and 1971. The highest Hg AR occurred in CE 1940 synchronous with the highest Hg production peak in Almadén mining district (southern Spain) and the Second World War. The record of Hg enrichment in Lake Montcortès shows a decrease during the last decades in Western Europe similar to other regional records and global emission models. This study highlights the exceptional quality of varved sequences to tease apart pollutants depositional mechanisms, identify historical periods of increased atmospheric pollution and provide a historical context for pollutant baseline values to make correct assessments of recent (atmospheric) pollution in lake ecosystems.

  18. Trace-elements in sheep grazing near a lead-zinc smelting complex at Port Pirie, South Australia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koh, T.S.; Judson, G.J.

    1986-07-01

    In South Australia, several studies have shown that heavy metal pollution of soils and plants occurs in the vicinity of a lead/zinc smelter at Port Pirie. Data on soil analysis indicates that at least 3400 km/sup 2/ of land near these smelters has been contaminated by the fallout of Pb, Zn and Cd. It is possible that contamination of soil and pasture by heavy metals may adversely affect the health of livestock grazing near the smelters. In sheep, Pb toxicity causes anorexia, abdominal pain and diarrhea while Zn or Cd supplementation reduces the Cu status. This study was undertaken tomore » investigate the effects of heavy metals on the trace-element status of sheep grazing at selected distances from the Port Pirie smelters.« less

  19. Zn/Cd ratios and cadmium isotope evidence for the classification of lead-zinc deposits

    PubMed Central

    Wen, Hanjie; Zhu, Chuanwei; Zhang, Yuxu; Cloquet, Christophe; Fan, Haifeng; Fu, Shaohong

    2016-01-01

    Lead-zinc deposits are often difficult to classify because clear criteria are lacking. In recent years, new tools, such as Cd and Zn isotopes, have been used to better understand the ore-formation processes and to classify Pb-Zn deposits. Herein, we investigate Cd concentrations, Cd isotope systematics and Zn/Cd ratios in sphalerite from nine Pb-Zn deposits divided into high-temperature systems (e.g., porphyry), low-temperature systems (e.g., Mississippi Valley type [MVT]) and exhalative systems (e.g., sedimentary exhalative [SEDEX]). Our results showed little evidence of fractionation in the high-temperature systems. In the low-temperature systems, Cd concentrations were the highest, but were also highly variable, a result consistent with the higher fractionation of Cd at low temperatures. The δ114/110Cd values in low-temperature systems were enriched in heavier isotopes (mean of 0.32 ± 0.31‰). Exhalative systems had the lowest Cd concentrations, with a mean δ114/110Cd value of 0.12 ± 0.50‰. We thus conclude that different ore-formation systems result in different characteristic Cd concentrations and fraction levels and that low-temperature processes lead to the most significant fractionation of Cd. Therefore, Cd distribution and isotopic studies can support better understanding of the geochemistry of ore-formation processes and the classification of Pb-Zn deposits. PMID:27121538

  20. Indicators: Sediment Mercury

    EPA Pesticide Factsheets

    Sediment mercury is mercury that has become embedded into the bottom substrates of aquatic ecosystems. Mercury is a common pollutant of aquatic ecosystems and it can have a substantial impact on both human and wildlife health.

  1. Atmospheric mercury in Changbai Mountain area, northeastern China II. The distribution of reactive gaseous mercury and particulate mercury and mercury deposition fluxes.

    PubMed

    Wan, Qi; Feng, Xinbin; Lu, Julia; Zheng, Wei; Song, Xinjie; Li, Ping; Han, Shijie; Xu, Hao

    2009-08-01

    Reactive gaseous mercury (RGM) and particulate mercury (Hgp) concentrations in ambient air from a remote site at Changbai Mountain area in northeastern China were intermittently monitored from August 2005 to July 2006 totaling 93 days representing fall, winter-spring and summer season, respectively. Rainwater and snow samples were collected during a whole year, and total mercury (THg) in rain samples were used to calculate wet depositional flux. A throughfall method and a model method were used to estimate dry depositional flux. Results showed mean concentrations of RGM and Hgp are 65 and 77 pg m(-3). Compared to background concentrations of atmospheric mercury species in Northern Hemisphere, RGM and Hgp are significantly elevated in Changbai area. Large values for standard deviation indicated fast reactivity and a low residence time for these mercury species. Seasonal variability is also important, with lower mercury levels in summer compared to other seasons, which is attributed to scavenging by rainfall and low local mercury emissions in summer. THg concentrations ranged from 11.5 to 15.9 ng L(-1) in rainwater samples and 14.9-18.6 ng L(-1) in throughfall samples. Wet depositional flux in Changbai area is calculated to be 8.4 microg m(-2) a(-1), and dry deposition flux is estimated to be 16.5 microg m(-2) a(-1) according to a throughfall method and 20.2 microg m(-2) a(-1) using a model method.

  2. Acute changes in cellular zinc alters zinc uptake rates prior to zinc transporter gene expression in Jurkat cells.

    PubMed

    Holland, Tai C; Killilea, David W; Shenvi, Swapna V; King, Janet C

    2015-12-01

    A coordinated network of zinc transporters and binding proteins tightly regulate cellular zinc levels. Canonical responses to zinc availability are thought to be mediated by changes in gene expression of key zinc transporters. We investigated the temporal relationships of actual zinc uptake with patterns of gene expression in membrane-bound zinc transporters in the human immortalized T lymphocyte Jurkat cell line. Cellular zinc levels were elevated or reduced with exogenous zinc sulfate or N,N,N',N-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), respectively. Excess zinc resulted in a rapid 44 % decrease in the rate of zinc uptake within 10 min. After 120 min, the expression of metallothionein (positive control) increased, as well as the zinc exporter, ZnT1; however, the expression of zinc importers did not change during this time period. Zinc chelation with TPEN resulted in a rapid twofold increase in the rate of zinc uptake within 10 min. After 120 min, the expression of ZnT1 decreased, while again the expression of zinc importers did not change. Overall, zinc transporter gene expression kinetics did not match actual changes in cellular zinc uptake with exogenous zinc or TPEN treatments. This suggests zinc transporter regulation may be the initial response to changes in zinc within Jurkat cells.

  3. Survey of metal tolerance in moderately halophilic eubacteria.

    PubMed Central

    Nieto, J J; Fernández-Castillo, R; Márquez, M C; Ventosa, A; Quesada, E; Ruiz-Berraquero, F

    1989-01-01

    The tolerance patterns, expressed as MICs, for 250 moderately halophilic eubacteria to 10 heavy metals were surveyed by using an agar dilution method. The moderate halophiles tested included 12 culture collection strains and fresh isolates representative of Deleya halophila (37 strains), Acinetobacter sp. (24 strains), Flavobacterium sp. (28 strains), and 149 moderately halophilic gram-positive cocci included in the genera Marinococcus, Sporosarcina, Micrococcus, and Staphylococcus. On the basis of the MICs, the collection strains showed, overall, similar responses to silver, cobalt, mercury, nickel, lead, and zinc. All were sensitive to silver, mercury, and zinc and tolerant of lead. The response to arsenate, cadmium, chromium, and copper was very heterogeneous. The metal susceptibility levels of the 238 freshly isolated strains were, in general, very heterogeneous among the four taxonomic groups as well as within the strains included in each group. The highest toxicities were found with mercury, silver, and zinc, while arsenate showed the lowest activity. All these strains were tolerant of nickel, lead, and chromium and sensitive to silver and mercury. Acinetobacter sp. strains were the most heavy-metal tolerant, with the majority of them showing tolerance of eight different metal ions. In contrast, Flavobacterium sp. strains were the most metal sensitive. The influence of salinity and yeast extract concentrations of the culture medium on the toxicity of the heavy metals tested for some representative strains was also studied. Lowering the salinity, in general, led to enhanced sensitivity to cadmium and, in some cases, to cobalt and copper. However, increasing the salinity resulted in only a slight decrease in the cadmium, copper, and nickel toxicities.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2802612

  4. Survey of metal tolerance in moderately halophilic eubacteria.

    PubMed

    Nieto, J J; Fernández-Castillo, R; Márquez, M C; Ventosa, A; Quesada, E; Ruiz-Berraquero, F

    1989-09-01

    The tolerance patterns, expressed as MICs, for 250 moderately halophilic eubacteria to 10 heavy metals were surveyed by using an agar dilution method. The moderate halophiles tested included 12 culture collection strains and fresh isolates representative of Deleya halophila (37 strains), Acinetobacter sp. (24 strains), Flavobacterium sp. (28 strains), and 149 moderately halophilic gram-positive cocci included in the genera Marinococcus, Sporosarcina, Micrococcus, and Staphylococcus. On the basis of the MICs, the collection strains showed, overall, similar responses to silver, cobalt, mercury, nickel, lead, and zinc. All were sensitive to silver, mercury, and zinc and tolerant of lead. The response to arsenate, cadmium, chromium, and copper was very heterogeneous. The metal susceptibility levels of the 238 freshly isolated strains were, in general, very heterogeneous among the four taxonomic groups as well as within the strains included in each group. The highest toxicities were found with mercury, silver, and zinc, while arsenate showed the lowest activity. All these strains were tolerant of nickel, lead, and chromium and sensitive to silver and mercury. Acinetobacter sp. strains were the most heavy-metal tolerant, with the majority of them showing tolerance of eight different metal ions. In contrast, Flavobacterium sp. strains were the most metal sensitive. The influence of salinity and yeast extract concentrations of the culture medium on the toxicity of the heavy metals tested for some representative strains was also studied. Lowering the salinity, in general, led to enhanced sensitivity to cadmium and, in some cases, to cobalt and copper. However, increasing the salinity resulted in only a slight decrease in the cadmium, copper, and nickel toxicities.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Volcanism on Mercury

    NASA Astrophysics Data System (ADS)

    Rothery, David A.

    2017-12-01

    Mercury has no recognized tracts of intact primary crust analogous to lunar highland crust, probably because Mercury's iron-poor magma ocean was insufficiently dense to enable crystallized silicates to float. Its surface is accepted to consist mostly of multiple generations of lavas, rather like terrestrial "large igneous provinces" or LIPs, emplaced in greatest volumes prior to about 3.5 Ga. Subsequently, erupted volumes decreased, and became largely confined to impact craters. Plains younger than about 3.7 Ga are scarred by so few impact craters that they are mapped as "smooth plains." Older plains are termed "intercrater plains." There is no consensus on whether plains with characteristics intermediate between smooth and intercrater plains can be consistently mapped (as "intermediate plains"). The volcanic nature of Mercury's smooth plains was ambiguous on images returned by the first mission to Mercury, Mariner 10 (three flybys in 1974–1975. Better imaging by MESSENGER (in orbit 2011–2015) removed doubt by documenting innumerable ghost craters and wrinkle ridges. Vents are obscure, as is normal in LIPs, but there are good examples of streamlined islands showing the passage of fast-flowing, low-viscosity lava. The causes of mantle partial melting necessary to supply Mercury's eruptions are unclear, but secular cooling of a small, one-plate planet is expected to lead to the decrease in volcanic activity that we observe. Factors include loss of primordial heat and declining rate of radiogenic heat production, and closure of pathways by planetary thermal contraction. Lava compositions resemble komatiites but with low iron content. Regional variations may reflect lateral and vertical heterogeneities in the mantle, or different degrees of partial melting. The cessation of effusive volcanism on Mercury is hard to date because the youngest areas are small. However, it probably continued until about 1 Ga. That was not the end of volcanism on the planet. MESSENGER

  6. Urinary mercury in people living near point sources of mercury emissions.

    PubMed

    Barregard, Lars; Horvat, Milena; Mazzolai, Barbara; Sällsten, Gerd; Gibicar, Darija; Fajon, Vesna; Dibona, Sergio; Munthe, John; Wängberg, Ingvar; Haeger Eugensson, Marie

    2006-09-01

    As part of the European Mercury Emissions from Chlor Alkali Plants (EMECAP) project, we tested the hypothesis that contamination of ambient air with mercury around chlor alkali plants using mercury cells would increase the internal dose of mercury in people living close to the plants. Mercury in urine (U-Hg) was determined in 225 individuals living near a Swedish or an Italian chlor alkali plant, and in 256 age- and sex-matched individuals from two reference areas. Other factors possibly affecting mercury exposure were examined. Emissions and concentrations of total gaseous mercury (TGM) around the plants were measured and modeled. No increase in U-Hg could be demonstrated in the populations living close to the plants. This was the case also when the comparison was restricted to subjects with no dental amalgam and low fish consumption. The emissions of mercury to air doubled the background level, but contributed only about 2 ng/m(3) to long-term averages in the residential areas. The median U-Hg levels in subjects with dental amalgam were 1.2 microg/g creatinine (micro/gC) in Italy and 0.6 microg/gC in Sweden. In individuals without dental amalgam, the medians were 0.9 microg/gC and 0.2 microg/gC, respectively. The number of amalgam fillings, as well as chewing, fish consumption, and female sex were associated with higher U-Hg. The difference between the countries is probably due to higher fish consumption in Italy, demethylated methyl mercury (MeHg) being partly excreted in urine. Post hoc power calculations showed that if the background mercury exposure is low it may be possible to demonstrate an increase in U-Hg of as little as about 10 ng/m(3) as a contribution to ambient mercury from a point source.

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

    PubMed

    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.

  8. Zinc Enzymes.

    ERIC Educational Resources Information Center

    Bertini, I.; And Others

    1985-01-01

    Discusses the role of zinc in various enzymes concerned with hydration, hydrolysis, and redox reactions. The binding of zinc to protein residues, properties of noncatalytic zinc(II) and catalytic zinc, and the reactions catalyzed by zinc are among the topics considered. (JN)

  9. Effects of Zinc on Particulate Methane Monooxygenase Activity and Structure*

    PubMed Central

    Sirajuddin, Sarah; Barupala, Dulmini; Helling, Stefan; Marcus, Katrin; Stemmler, Timothy L.; Rosenzweig, Amy C.

    2014-01-01

    Particulate methane monooxygenase (pMMO) is a membrane-bound metalloenzyme that oxidizes methane to methanol in methanotrophic bacteria. Zinc is a known inhibitor of pMMO, but the details of zinc binding and the mechanism of inhibition are not understood. Metal binding and activity assays on membrane-bound pMMO from Methylococcus capsulatus (Bath) reveal that zinc inhibits pMMO at two sites that are distinct from the copper active site. The 2.6 Å resolution crystal structure of Methylocystis species strain Rockwell pMMO reveals two previously undetected bound lipids, and metal soaking experiments identify likely locations for the two zinc inhibition sites. The first is the crystallographic zinc site in the pmoC subunit, and zinc binding here leads to the ordering of 10 previously unobserved residues. A second zinc site is present on the cytoplasmic side of the pmoC subunit. Parallels between these results and zinc inhibition studies of several respiratory complexes suggest that zinc might inhibit proton transfer in pMMO. PMID:24942740

  10. The Texarkana mercury incident.

    PubMed

    Lowry, L K; Rountree, P P; Levin, J L; Collins, S; Anger, W K

    1999-10-01

    In November 1997, 2 teenagers allegedly removed a large amount of metallic mercury from an abandoned sign plant and distributed the material among friends. One teenager developed symptoms and admitted playing with mercury to his physician. His blood mercury was elevated. In February 1998, faculty from the University of Texas Health Center at Tyler conducted an investigation that included in-depth evaluations on 10 patients with urine mercury concentrations up to 100 micrograms/L. Exposure pathways and timelines were reconstructed from records assembled by the Arkansas State Health Department epidemiologist. Mercury contamination was found among teenagers, children, and adults who came in contact with the metal. Biomarkers of exposure documented reduction in mercury concentrations after these persons were removed from their homes and sources of mercury. Neurobehavioral assessment, including assessment of tremor, failed to establish a relationship between mercury exposure and performance.

  11. Lead exposure in a tank demolition crew: implications for the new OSHA construction lead standard.

    PubMed

    Waller, K; Osorio, A M; Jones, J

    1994-11-01

    The Federal Occupational Safety and Health Administration (OSHA) has recently extended the basic health and safety provisions of the OSHA lead standard for general industry to workers in the construction industry. In this report we describe a tank demolition worksite that midway through the project strengthened its lead exposure control activities to a level that approximated the current lead standard. Of 12 tested ironworkers and laborers who worked at the site before the change, zinc protoporphyrin levels increased and seven developed blood lead levels (BLL) > 50 micrograms/dL. After the change these workers' BLLs declined. Six workers hired after the change did not experience increases in zinc protoporphyrin and none developed BLL > 25 micrograms/dL. The experience at this worksite demonstrates the usefulness and feasibility of implementing the current lead standard in construction settings.

  12. 40 CFR 421.256 - Pretreatment standards for new sources.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0.364 0.169 Mercury 0.195 0.078 Silver 0.377 0.156 Zinc 1.326 0.546 Gold 0.130 (b) Silver chloride reduction spent solution. PSNS for the....024 Silver 0.116 0.048 Zinc 0.408 0.168 Gold 0.040 (c) Electrolytic cells wet air pollution control...

  13. 40 CFR 421.256 - Pretreatment standards for new sources.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0.364 0.169 Mercury 0.195 0.078 Silver 0.377 0.156 Zinc 1.326 0.546 Gold 0.130 (b) Silver chloride reduction spent solution. PSNS for the....024 Silver 0.116 0.048 Zinc 0.408 0.168 Gold 0.040 (c) Electrolytic cells wet air pollution control...

  14. 40 CFR 421.256 - Pretreatment standards for new sources.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0.364 0.169 Mercury 0.195 0.078 Silver 0.377 0.156 Zinc 1.326 0.546 Gold 0.130 (b) Silver chloride reduction spent solution. PSNS for the....024 Silver 0.116 0.048 Zinc 0.408 0.168 Gold 0.040 (c) Electrolytic cells wet air pollution control...

  15. Global mercury emissions from combustion in light of international fuel trading.

    PubMed

    Chen, Yilin; Wang, Rong; Shen, Huizhong; Li, Wei; Chen, Han; Huang, Ye; Zhang, Yanyan; Chen, Yuanchen; Su, Shu; Lin, Nan; Liu, Junfeng; Li, Bengang; Wang, Xilong; Liu, Wenxin; Coveney, Raymond M; Tao, Shu

    2014-01-01

    The spatially resolved emission inventory is essential for understanding the fate of mercury. Previous global mercury emission inventories for fuel combustion sources overlooked the influence of fuel trading on local emission estimates of many countries, mostly developing countries, for which national emission data are not available. This study demonstrates that in many countries, the mercury content of coal and petroleum locally consumed differ significantly from those locally produced. If the mercury content in locally produced fuels were used to estimate emission, then the resulting global mercury emissions from coal and petroleum would be overestimated by 4.7 and 72%, respectively. Even higher misestimations would exist in individual countries, leading to strong spatial bias. On the basis of the available data on fuel trading and an updated global fuel consumption database, a new mercury emission inventory for 64 combustion sources has been developed. The emissions were mapped at 0.1° × 0.1° resolution for 2007 and at country resolution for a period from 1960 to 2006. The estimated global total mercury emission from all combustion sources (fossil fuel, biomass fuel, solid waste, and wildfires) in 2007 was 1454 Mg (1232-1691 Mg as interquartile range from Monte Carlo simulation), among which elementary mercury (Hg(0)), divalent gaseous mercury (Hg(2+)), and particulate mercury (Hg(p)) were 725, 548, and 181 Mg, respectively. The total emission from anthropogenic sources, excluding wildfires, was 1040 Mg (886-1248 Mg), with coal combustion contributing more than half. Globally, total annual anthropogenic mercury emission from combustion sources increased from 285 Mg (263-358 Mg) in 1960 to 1040 Mg (886-1248 Mg) in 2007, owing to an increased fuel consumption in developing countries. However, mercury emissions from developed countries have decreased since 2000.

  16. [Spatial distribution and ecological significance of heavy metals in soils from Chatian mercury mining deposit, western Hunan province].

    PubMed

    Sun, Hong-Fei; Li, Yong-Hu; Ji, Yan-Fang; Yang, Lin-Sheng; Wang, Wu-Yi

    2009-04-15

    Ores, waste tailings and slag, together with three typical soil profiles (natural soil profiles far from mine entrance and near mine entrance, soil profile under slag) in Chatian mercury mining deposit (CMD), western Hunan province were sampled and their concentrations of mercury (Hg), arsenic (As), lead (Pb), cadmium (Cd), zinc (Zn) were determined by HG-ICP-AES and ICP-MS. Enrichment factor and correlation analysis were taken to investigate the origins, distribution and migration of Hg, as well as other heavy metals in the CMD. The results show that Hg is enriched in the bottom of the soil profile far from mine entrance but accumulated in the surface of soil profiles near mine entrance and under slag. The soil profiles near mine entrance and under slag are both contaminated by Hg, while the latter is contaminated more heavily. In the soil profile under slag, Hg concentration in the surface soil, Hg average concentration in the total profile, and the leaching depth of soil Hg are 640 microg x g(-1), (76.74 +/- 171.71) microg x g(-1), and more than 100 cm, respectively; while 6.5 microg x g(-1), (2.74 +/- 1.90) microg x g(-1), and 40 cm, respectively, are found in the soil profile near mine entrance. Soil in the mercury mine area is also polluted by Cd, As, Pb, Zn besides metallogenic element Hg, among which Cd pollution is relatively heavier than others. The mobility of the studied heavy metals in soil follows the order as Hg > Cd > As > Zn approximately equal to Pb. The leaching depth of the heavy metals is influenced by total concentration in the surface soil and soil physico-chemical parameters. The origins, distribution and migration of heavy metals in soil profile in the mining area are related to primary geological environment, and strongly influenced by human mining activities.

  17. Ultraviolet and infrared absorption spectra of Cr2O3 doped-sodium metaphosphate, lead metaphosphate and zinc metaphosphate glasses and effects of gamma irradiation: a comparative study.

    PubMed

    Marzouk, M A; ElBatal, F H; Abdelghany, A M

    2013-10-01

    The effects of gamma irradiation on spectral properties of Cr2O3-doped phosphate glasses of three varieties, namely sodium metaphosphate, lead metaphosphate and zinc metaphosphate have been investigated. Optical spectra of the undoped samples reveal strong UV absorption bands which are attributed to the presence of trace iron impurities in both the sodium and zinc phosphate glasses while the lead phosphate glass exhibits broad UV near visible bands due to combined absorption of both trace iron impurities and divalent lead ions. The effect of chromium oxide content has been investigated. The three different Cr2O3-doped phosphate glasses reveal spectral visible bands varying in their position and intensity and splitting due to the different field strengths of the Na(+), Pb(2+), Zn(2+) cations, together with the way they are housed in the network and their effects on the polarisability of neighboring oxygens ligands. The effects of gamma irradiation on the optical spectral properties of the various glasses have been compared. The different effects for lead and zinc phosphate are related to the ability of Pb(2+), and Zn(2+) to form additional structural units causing stability of the network towards gamma irradiation. Also, the introduction of the transition metal chromium ions reveals some shielding behavior towards irradiation. Infrared absorption spectra of the three different base phosphate glasses show characteristic vibrations due to various phosphate groups depending on the type of glass and Cr2O3 is observed to slightly affect the IR spectra. Gamma irradiation causes minor variations in some of the intensities of the IR spectra but the main characteristic bands due to phosphate groups remain in their number and position. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Mercury Project

    NASA Image and Video Library

    1961-01-01

    Ham, a three-year-old chimpanzee, in the spacesuit he would wear for the second Mercury- Redstone (MR-2) suborbital test flight in January, 1961. NASA used chimpanzees and other primates to test the Mercury capsule before launching the fisrt American astronaut, Alan Shepard, in May 1961. The Mercury capsule rode atop a modified Redstone rocket, developed by Dr. Wernher von Braun and the German Rocket Team in Huntsville, Alabama.

  19. 40 CFR 461.72 - Effluent limitations representing the degree of effluent reduction attainable by the application...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... English units—pounds per 1,000,000 pounds of Zinc Chromium 0.24 0.099 Mercury 0.14 0.055 Silver 0.23 0.093... English units—pounds per 1,000,000 pounds of Zinc Chromium 0.030 0.012 Mercury 0.017 0.007 Silver 0.028 0.../kg of Zinc English units—pounds per 1,000,000 pounds of Zinc Chromium 9.53 3.90 Mercury 5.42 2.17...

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

    PubMed

    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.

  1. Zinc

    MedlinePlus

    ... Using toothpastes containing zinc, with or without an antibacterial agent, appears to prevent plaque and gingivitis. Some ... is some evidence that zinc has some antiviral activity against the herpes virus. Low zinc levels can ...

  2. Electron Microscopy Imaging of Zinc Soaps Nucleation in Oil Paint.

    PubMed

    Hermans, Joen; Osmond, Gillian; van Loon, Annelies; Iedema, Piet; Chapman, Robyn; Drennan, John; Jack, Kevin; Rasch, Ronald; Morgan, Garry; Zhang, Zhi; Monteiro, Michael; Keune, Katrien

    2018-06-04

    Using the recently developed techniques of electron tomography, we have explored the first stages of disfiguring formation of zinc soaps in modern oil paintings. The formation of complexes of zinc ions with fatty acids in paint layers is a major threat to the stability and appearance of many late 19th and early 20th century oil paintings. Moreover, the occurrence of zinc soaps in oil paintings leading to defects is disturbingly common, but the chemical reactions and migration mechanisms leading to large zinc soap aggregates or zones remain poorly understood. State-of-the-art scanning (SEM) and transmission (TEM) electron microscopy techniques, primarily developed for biological specimens, have enabled us to visualize the earliest stages of crystalline zinc soap growth in a reconstructed zinc white (ZnO) oil paint sample. In situ sectioning techniques and sequential imaging within the SEM allowed three-dimensional tomographic reconstruction of sample morphology. Improvements in the detection and discrimination of backscattered electrons enabled us to identify local precipitation processes with small atomic number contrast. The SEM images were correlated to low-dose and high-sensitivity TEM images, with high-resolution tomography providing unprecedented insight into the structure of nucleating zinc soaps at the molecular level. The correlative approach applied here to study phase separation, and crystallization processes specific to a problem in art conservation creates possibilities for visualization of phase formation in a wide range of soft materials.

  3. Concentrations of Trace Elements in Hemodialysis Patients: A Prospective Cohort Study.

    PubMed

    Tonelli, Marcello; Wiebe, Natasha; Bello, Aminu; Field, Catherine J; Gill, John S; Hemmelgarn, Brenda R; Holmes, Daniel T; Jindal, Kailash; Klarenbach, Scott W; Manns, Braden J; Thadhani, Ravi; Kinniburgh, David

    2017-11-01

    Low concentrations and excessive concentrations of trace elements have been commonly reported in hemodialysis patients, but available studies have several important limitations. Random sample of patients drawn from a prospective cohort. 198 incident hemodialysis patients treated in 3 Canadian centers. We used mass spectrometry to measure plasma concentrations of the 25 elements at baseline, 6 months, 1 year, and 2 years following enrollment in the cohort. We focused on low concentrations of zinc, selenium, and manganese and excessive concentrations of lead, arsenic, and mercury; low and excessive concentrations of the other 19 trace elements were treated as exploratory analyses. Low and excessive concentrations were based on the 5th and 95th percentile plasma concentrations from healthy reference populations. At all 4 occasions, low zinc, selenium, and manganese concentrations were uncommon in study participants (≤5.1%, ≤1.8%, and ≤0.9% for zinc, selenium, and manganese, respectively) and a substantial proportion of participants had concentrations that exceeded the 95th percentile (≥65.2%, ≥74.2%, and ≥19.7%, respectively). Almost all participants had plasma lead concentrations above the 95th percentile at all time points. The proportion of participants with plasma arsenic concentrations exceeding the 95th percentile was relatively constant over time (9.1%-9.8%); the proportion with plasma mercury concentrations that exceeded the 95th percentile varied between 15.2% and 29.3%. Low arsenic, platinum, tungsten, and beryllium concentrations were common (>50%), as were excessive cobalt, manganese, zinc, vanadium, cadmium, selenium, barium, antimony, nickel, molybdenum, lead, and chromium concentrations. There was no evidence that low zinc, selenium, or manganese concentrations exist in most contemporary Canadian hemodialysis patients. Some patients have excessive plasma arsenic and mercury concentrations, and excessive lead concentrations were common

  4. Mercury bioremediation by mercury accumulating Enterobacter sp. cells and its alginate immobilized application.

    PubMed

    Sinha, Arvind; Khare, Sunil Kumar

    2012-02-01

    The effective microbial remediation of the mercury necessitates the mercury to be trapped within the cells without being recycled back to the environment. The study describes a mercury bioaccumulating strain of Enterobacter sp., which remediated mercury from the medium simultaneous to its growth. The transmission electron micrographs and electron dispersive X-ray analysis revealed the accumulation of remediated mercury as nano-size particles in the cytoplasm as well as on the cell wall. The Enterobacter sp. in the present work was able to accumulate mercury, without being engineered in its native form. The possibility of recovering the accumulated mercury from the cells is also indicated. The applicability of the alginate immobilized cells in removing mercury from synthetic and complex industrial effluent in a batch mode was amply demonstrated. The initial load of 7.3 mg l(-1) mercury in the industrial effluent was completely removed in 72 h. The cells immobilized in calcium alginate were similarly effective in the complete removal of 5 mg l(-1) HgCl(2) of mercury from the synthetic effluent in less than 72 h. The immobilized cells could be reused for multiple cycles.

  5. Priority-pollutant trace elements in streambed sediments of the Cook Inlet basin, Alaska, 1998-2000

    USGS Publications Warehouse

    Frenzel, Steven A.

    2002-01-01

    Trace element concentrations in 48 streambed sediment samples collected at 47 sites in the Cook Inlet Basin, Alaska, were compared to concentrations from studies in the conterminous United States using identical methods and to Probable Effect Concentrations. Concentrations of arsenic, chromium, mercury, and nickel in the 0.063-mm size fraction of streambed sediments from the Cook Inlet Basin were elevated relative to reference sites in the conterminous United States. Concentrations of cadmium, lead, and zinc were highest at the most urbanized site in Anchorage and at two sites downstream from an ore body in Lake Clark National Park and Preserve. At least 35 percent of the 48 samples collected in the Cook Inlet Basin exceeded the Probable Effect Concentration for arsenic, chromium, or nickel. More than 50 percent of the samples were considered to have low potential toxicity for cadmium, lead, mercury, nickel, selenium, and zinc. A Probable Effect Concentration quotient that reflects the combined toxicity of arsenic, cadmium, chromium, copper, lead, mercury, nickel, and zinc was exceeded in 44 percent of the samples from the Cook Inlet Basin. The potential toxicity was high in the Denali and Lake Clark National Parks and Preserves where organic carbon concentrations in streambed sediments were low. However, potential toxicity results should be considered in context with the very small amounts of fine-grained sediment present in the streambed sediments of the Cook Inlet Basin.

  6. Mercury Surveillance Program

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Background on mercury exposure is presented including forms, sources, permissible exposure limits, and physiological effects. The purpose of the Mercury Surveillance Program at LeRC is outlined, and the specifics of the Medical Surveillance Program for Mercury Exposure at LeRC are discussed.

  7. Using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to characterize copper, zinc and mercury along grizzly bear hair providing estimate of diet.

    PubMed

    Noël, Marie; Christensen, Jennie R; Spence, Jody; Robbins, Charles T

    2015-10-01

    We enhanced an existing technique, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), to function as a non-lethal tool in the temporal characterization of trace element exposure in wild mammals. Mercury (Hg), copper (Cu), cadmium (Cd), lead (Pb), iron (Fe) and zinc (Zn) were analyzed along the hair of captive and wild grizzly bears (Ursus arctos horribilis). Laser parameters were optimized (consecutive 2000 μm line scans along the middle line of the hair at a speed of 50 μm/s; spot size=30 μm) for consistent ablation of the hair. A pressed pellet of reference material DOLT-2 and sulfur were used as external and internal standards, respectively. Our newly adapted method passed the quality control tests with strong correlations between trace element concentrations obtained using LA-ICP-MS and those obtained with regular solution-ICP-MS (r(2)=0.92, 0.98, 0.63, 0.57, 0.99 and 0.90 for Hg, Fe, Cu, Zn, Cd and Pb, respectively). Cross-correlation analyses revealed good reproducibility between trace element patterns obtained from hair collected from the same bear. One exception was Cd for which external contamination was observed resulting in poor reproducibility. In order to validate the method, we used LA-ICP-MS on the hair of five captive grizzly bears fed known and varying amounts of cutthroat trout over a period of 33 days. Trace element patterns along the hair revealed strong Hg, Cu and Zn signals coinciding with fish consumption. Accordingly, significant correlations between Hg, Cu, and Zn in the hair and Hg, Cu, and Zn intake were evident and we were able to develop accumulation models for each of these elements. While the use of LA-ICP-MS for the monitoring of trace elements in wildlife is in its infancy, this study highlights the robustness and applicability of this newly adapted method. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Distribution of total mercury and methyl mercury in water, sediment, and fish from South Florida estuaries

    USGS Publications Warehouse

    Kannan, K.; Smith, R.G.; Lee, R.F.; Windom, H.L.; Heitmuller, P.T.; Macauley, J.M.; Summers, J.K.

    1998-01-01

    Concentrations of total mercury and methyl mercury were determined in sediment and fish collected from estuarine waters of Florida to understand their distribution and partitioning. Total mercury concentrations in sediments ranged from 1 to 219 ng/g dry wt. Methyl mercury accounted for, on average, 0.77% of total mercury in sediment. Methyl mercury concentrations were not correlated with total mercury or organic carbon content in sediments. The concentrations of total mercury in fish muscle were between 0.03 and 2.22 (mean: 0.31) ??g/g, wet wt, with methyl mercury contributing 83% of total mercury. Methyl mercury concentrations in fish muscle were directly proportional to total mercury concentrations. The relationship of total and methyl mercury concentrations in fish to those of sediments from corresponding locations was fish-species dependent, in addition to several abiotic factors. Among fish species analyzed, hardhead catfish, gafftopsail catfish, and sand seatrout contained the highest concentrations of mercury. Filtered water samples from canals and creeks that discharge into the Florida Bay showed mercury concentrations of 3-7.4 ng/L, with methyl mercury accounting for <0.03-52% of the total mercury. Consumption of fish containing 0.31 ??g mercury/g wet wt, the mean concentration found in this study, at rates greater than 70 g/day, was estimated to be hazardous to human health.

  9. Mercury Sodium Tail

    NASA Image and Video Library

    2015-04-16

    This image from NASA MESSENGER spacecraft is stitched together from thousands of observations made over the past 4 years by the MASCS/UVVS instrument, which measures sunlight scattered off of Mercury tenuous atmosphere. Scattered sunlight gives the sodium a bright orange glow. This scattering process also gives sodium atoms a push - this "radiation pressure" is strong enough, during parts of Mercury's year, to strip the atmosphere and give Mercury a long glowing tail. Someone standing on Mercury's nightside at the right time of year would see a faint orange similar to a city sky illuminated by sodium lamps! Instrument: Mercury Atmospheric and Surface Composition Spectrometer (MASCS)/Ultraviolet and Visible Spectrometer (UVVS) http://photojournal.jpl.nasa.gov/catalog/PIA19418

  10. Mercury Project

    NASA Image and Video Library

    1959-01-01

    Dr. Wernher von Braun, Director of the Army Ballistic Missile Agency's (ABMA) Development Operations Division, poses with the original Mercury astronauts in ABMA's Fabrication Laboratory during a 1959 visit. Inspecting Mercury-Redstone hardware are from left to right, Alan Shepard, Donald Deke Slayton, Virgil Gus Grissom, von Braun, Gordon Cooper, Wally Schirra, John Glenn, and Scott Carpenter. Project Mercury officially began October 7, 1958 as the United States' first manned space program.

  11. Effect of zinc and lead on the physiological and biochemical properties of aquatic plant Lemna minor: its potential role in phytoremediation

    NASA Astrophysics Data System (ADS)

    Jayasri, M. A.; Suthindhiran, K.

    2017-06-01

    Plants have gained importance in situ bioremediation of heavy metals. In the present study, different concentrations of zinc (Zn2+) (0.5, 5, 10, 15, 20 mg/l) and lead (Pb2+) (1, 2, 4, 6, 8 mg/l) were used to evaluate metal tolerance level of Lemna minor. L.minor were exposed to metals for 4 days and tested for its dry to fresh weight ratio (DW/FW), photosynthetic pigments production and protein content. The oxidative damage was detected by measuring catalase activity. L.minor showed tolerance against Zn2+ and Pb2+ at a concentration of 10 and 4 mg/l, respectively. Among the metals, Pb2+ showed a significant toxicity at 8 mg/l. High concentration (20 mg/l of Zn2+ and 8 mg/l of Pb2+) of the metals displayed a considerable negative effect on soluble proteins (13 fold decrease with Zn2+ and 4 fold decrease with Pb2+) and photosynthetic pigments (twofold decrease with Zn2+ and onefold decrease with Pb2+) and lead to a consequent reduction in number of fronds. Further, the catalase was greatly increased (twofold decrease with Zn2+ and sixfold decrease with Pb2+) under metal stress. The results indicate that L.minor withstands Zn2+ and Pb2+ toxicity up to the concentration of 10 and 4 mg/l, respectively. Hence, the metal tolerant property of this plant shall be exploited for bioremediation of Zinc and Lead in polluted water. Further, the detailed and wide range of heavy metal toxicity studies should be done to reveal the possible use of this plant on large scale bioremediation purpose.

  12. Microplate technique for determining accumulation of metals by algae

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hassett, J.M.; Jennett, J.C.; Smith, J.E.

    1981-05-01

    A microplate technique was developed to determine the conditions under which pure cultures of algae removed heavy metals from aqueous solutions. Variables investigated included algal species and strain, culture age (11 and 44 days), metal (mercury, lead, cadmium, and zinc), pH, effects of different buffer solutions, and time of exposure. Plastic, U-bottomed microtiter plates were used in conjunction with heavy metal radionuclides to determine concentration factors for metal-alga combinations. The technique developed was rapid, statistically reliable, and economical of materials and cells. All species of algae studied removed mercury from solution. Green algae proved better at accumulating cadmium than didmore » blue-green algae. No alga studied removed zinc, perhaps because cells were maintained in the dark during the labeling period. Chlamydomonas sp. proved superior in ability to remove lead from solution.« less

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

    EPA Science Inventory

    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, ...

  14. Mercury Emission Measurement in Coal-Fired Boilers by Continuous Mercury Monitor and Ontario Hydro Method

    NASA Astrophysics Data System (ADS)

    Zhu, Yanqun; Zhou, Jinsong; He, Sheng; Cai, Xiaoshu; Hu, Changxin; Zheng, Jianming; Zhang, Le; Luo, Zhongyang; Cen, Kefa

    2007-06-01

    The mercury emission control approach attaches more importance. The accurate measurement of mercury speciation is a first step. Because OH method (accepted method) can't provide the real-time data and 2-week time for results attained, it's high time to seek on line mercury continuous emission monitors(Hg-CEM). Firstly, the gaseous elemental and oxidized mercury were conducted to measure using OH and CEM method under normal operation conditions of PC boiler after ESP, the results between two methods show good consistency. Secondly, through ESP, gaseous oxidized mercury decrease a little and particulate mercury reduce a little bit, but the elemental mercury is just the opposite. Besides, the WFGD system achieved to gaseous oxidized mercury removal of 53.4%, gaseous overall mercury and elemental mercury are 37.1% and 22.1%, respectively.

  15. Investigating Atmospheric Mercury with the U.S. Geological Survey Mobile Mercury Laboratory

    USGS Publications Warehouse

    Kolker, Allan

    2007-01-01

    Atmospheric mercury is thought to be an important source of mercury present in fish, resulting in numerous local, statewide, tribal, and province-wide fish consumption advisories in the United States and Canada (U.S. Environmental Protection Agency, 2007a). To understand how mercury occurs in the atmosphere and its potential to be transferred from the atmosphere to the biosphere, the U.S. Geological Survey (USGS) has been investigating sources and forms of atmospheric mercury, especially in locations where the amount of mercury deposited from precipitation is above average.

  16. Mercury cycling in terrestrial watersheds

    USGS Publications Warehouse

    Shanley, James B.; Bishop, Kevin; Banks, Michael S.

    2012-01-01

    This chapter discusses mercury cycling in the terrestrial landscape, including inputs from the atmosphere, accumulation in soils and vegetation, outputs in streamflow and volatilization, and effects of land disturbance. Mercury mobility in the terrestrial landscape is strongly controlled by organic matter. About 90% of the atmospheric mercury input is retained in vegetation and organic matter in soils, causing a buildup of legacy mercury. Some mercury is volatilized back to the atmosphere, but most export of mercury from watersheds occurs by streamflow. Stream mercury export is episodic, in association with dissolved and particulate organic carbon, as stormflow and snowmelt flush organic-rich shallow soil horizons. The terrestrial landscape is thus a major source of mercury to downstream aquatic environments, where mercury is methylated and enters the aquatic food web. With ample organic matter and sulfur, methylmercury forms in uplands as well—in wetlands, riparian zones, and other anoxic sites. Watershed features (topography, land cover type, and soil drainage class) are often more important than atmospheric mercury deposition in controlling the amount of stream mercury and methylmercury export. While reductions in atmospheric mercury deposition may rapidly benefit lakes, the terrestrial landscape will respond only over decades, because of the large stock and slow turnover of legacy mercury. We conclude with a discussion of future scenarios and the challenge of managing terrestrial mercury.

  17. Mercury in breast milk - a health hazard for infants in gold mining areas?

    PubMed

    Bose-O'Reilly, Stephan; Lettmeier, Beate; Roider, Gabriele; Siebert, Uwe; Drasch, Gustav

    2008-10-01

    Breast-feeding can be a source of mercury exposure for infants. The main concern up to now is methyl-mercury exposure of women at child-bearing age. Certain fish species have high levels of methyl-mercury leading to consumer's advisory guidelines in regard of fish consumption to protect infants from mercury exposure passing through breast milk. Little is known about the transfer of inorganic mercury passing through breast milk to infants. Epidemiological studies showed negative health effects of inorganic mercury in gold mining areas. Small-scale gold miners use mercury to extract the gold from the ore. Environmental and health assessments of gold mining areas in Indonesia, Tanzania and Zimbabwe showed a high exposure with inorganic mercury in these gold mining areas, and a negative health impact of the exposure to the miners and the communities. This paper reports about the analysis and the results of 46 breast milk samples collected from mercury-exposed mothers. The median level of 1.87mug/l is fairly high compared to other results from literature. Some breast milk samples showed very high levels of mercury (up to 149mug/l). Fourteen of the 46 breast milk samples exceed 4mug/l which is considered to be a "high" level. US EPA recommends a "Reference Dose" of 0.3mug inorganic mercury/kg body weight/day [United States Environmental Protection Agency, 1997. Volume V: Health Effects of Mercury and Mercury Compounds. Study Report EPA-452/R-97-007: US EPA]. Twenty-two of the 46 children from these gold mining areas had a higher calculated total mercury uptake. The highest calculated daily mercury uptake of 127mug exceeds by far the recommended maximum uptake of inorganic mercury. Further systematic research of mercury in breast milk from small-scale gold mining areas is needed to increase the knowledge about the bio-transfer of mercury from mercury vapour-exposed mothers passing through breast milk to the breast-fed infant.

  18. Mercury in municipal solid wastes and New Jersey mercury prevention and reduction program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Erdogan, H.; Stevenson, E.

    1994-12-31

    Mercury is a very toxic heavy metal which accumulates in the brain causing neurological damages involving psychasthenic and vegetative syndrome. At high exposure levels it causes behavioral and personality changes, loss of memory and insomnia. Long-term exposure or exposure during pregnancy to mercury or mercury compounds can permanently damage the kidney and fetus. In addition to potential effects on human health, mercury poisoning can also affect other living organisms. Mercury is different than other heavy metals. It consistently biomagnifies and bioaccumulates within the aquatic food chain. Global sources of mercury release are both natural and anthropogenic. Natural sources include volatilizationmore » of gaseous-mercury iron soils ana rocks, volcanic releases, evaporation from the ocean and other water bodies. Anthropogenic sources are fuel and coal combustion, mining, smelting, manufacturing activities, disposal of sludge, pesticides, animal and food waste, and incineration of municipal solid waste. Worldwide combustion of municipal solid waste is the second largest source of atmospheric emission of mercury. In New Jersey, incineration of solid waste is the largest source of atmospheric emission of mercury. The New Jersey Department of Environmental Protection and Energy (NJDEPE) has developed a comprehensive program to control and prevent emission of mercury resulting from combustion municipal solid waste.« less

  19. Biomarkers of mercury exposure at a mercury recycling facility in Ukraine.

    PubMed

    Gibb, Herman Jones; Kozlov, Kostj; Buckley, Jessie Poulin; Centeno, Jose; Jurgenson, Vera; Kolker, Allan; Conko, Kathryn; Landa, Edward; Panov, Boris; Panov, Yuri; Xu, Hanna

    2008-08-01

    This study evaluates biomarkers of occupational mercury exposure among workers at a mercury recycling operation in Gorlovka, Ukraine. The 29 study participants were divided into three occupational categories for analysis: (1) those who worked in the mercury recycling operation (Group A, n = 8), (2) those who worked at the facility but not in the yard where the recycling was done (Group B, n = 14), and (3) those who did not work at the facility (Group C, n = 7). Urine, blood, hair, and nail samples were collected from the participants, and a questionnaire was administered to obtain data on age, gender, occupational history, smoking, alcohol consumption, fish consumption, tattoos, dental amalgams, home heating system, education, source of drinking water, and family employment in the former mercury mine/smelter located on the site of the recycling facility. Each factor was tested in a univariate regression with total mercury in urine, blood, hair, and nails. Median biomarker concentrations were 4.04 microg/g-Cr (urine), 2.58 microg/L (blood), 3.95 microg/g (hair), and 1.16 microg/g (nails). Occupational category was significantly correlated (p < 0.001) with both blood and urinary mercury concentrations but not with hair or nail mercury. Four individuals had urinary mercury concentrations in a range previously found to be associated with subtle neurological and subjective symptoms (e.g., fatigue, loss of appetite, irritability), and one worker had a urinary mercury concentration in a range associated with a high probability of neurological effects and proteinuria. Comparison of results by occupational category found that workers directly involved with the recycling operation had the highest blood and urinary mercury levels. Those who worked at the facility but were not directly involved with the recycling operation had higher levels than those who did not work at the facility.

  20. Biomarkers of mercury exposure at a mercury recycling facility in Ukraine

    USGS Publications Warehouse

    Gibb, H.J.; Kozlov, K.; Buckley, J.P.; Centeno, J.; Jurgenson, V.; Kolker, A.; Conko, K.; Landa, E.; Panov, B.; Panov, Y.; Xu, H.

    2008-01-01

    This study evaluates biomarkers of occupational mercury exposure among workers at a mercury recycling operation in Gorlovka, Ukraine. The 29 study participants were divided into three occupational categories for analysis: (1) those who worked in the mercury recycling operation (Group A, n = 8), (2) those who worked at the facility but not in the yard where the recycling was done (Group B, n = 14), and (3) those who did not work at the facility (Group C, n = 7). Urine, blood, hair, and nail samples were collected from the participants, and a questionnaire was administered to obtain data on age, gender, occupational history, smoking, alcohol consumption, fish consumption, tattoos, dental amalgams, home heating system, education, source of drinking water, and family employment in the former mercury mine/smelter located on the site of the recycling facility. Each factor was tested in a univariate regression with total mercury in urine, blood, hair, and nails. Median biomarker concentrations were 4.04 ??g/g-Cr (urine), 2.58 ??g/L (blood), 3.95 ??g/g (hair), and 1.16 ??g/g (nails). Occupational category was significantly correlated (p < 0.001) with both blood and urinary mercury concentrations but not with hair or nail mercury. Four individuals had urinary mercury concentrations in a range previously found to be associated with subtle neurological and subjective symptoms (e.g., fatigue, loss of appetite, irritability), and one worker had a urinary mercury concentration in a range associated with a high probability of neurological effects and proteinuria. Comparison of results by occupational category found that workers directly involved with the recycling operation had the highest blood and urinary mercury levels. Those who worked at the facility but were not directly involved with the recycling operation had higher levels than those who did not work at the facility. Copyright ?? 2008 JOEH, LLC.

  1. Total mercury, cadmium and lead levels in main export fish of Sri Lanka.

    PubMed

    Jinadasa, B K K K; Edirisinghe, E M R K B; Wickramasinghe, I

    2014-01-01

    Total mercury (Hg), cadmium (Cd) and lead (Pb) levels were determined in the muscle of four commercialised exported fish species Thunnus albacares (yellowfin tuna), Xiphias gladius (swordfish), Makaira indica (black marlin) and Lutjanus sp (red snapper) collected from the Indian Ocean, Sri Lanka, during July 2009-March 2010 and measured by atomic absorption spectrophotometry. Results show that swordfish (n = 176) contained the highest total Hg (0.90 ± 0.51 mg/kg) and Cd (0.09 ± 0.13 mg/kg) levels, whereas yellowfin tuna (n = 140) contained the highest Pb levels (0.11 ± 0.16 mg/kg). The lowest total Hg (0.16 ± 0.11 mg/kg), Cd (0.01 ± 0.01 mg/kg) and Pb (0.04 ± 0.04 mg/kg) levels were found in red snapper (n = 28). Black marlin (n = 24) contained moderate levels of total Hg (0.49 ± 0.37), Cd (0.02 ± 0.02) and Pb (0.05 ± 0.05). Even though there are some concerns during certain months of the year, this study demonstrates the safety of main export fish varieties in terms of total Hg, Cd and Pb.

  2. MESSENGER View of Mercury's Caloris Basin

    NASA Image and Video Library

    2017-12-08

    NASA image acquired October 28, 2011 This stunning, and as of yet unnamed, crater lies within the Caloris basin. Its floor provides another example of the beautiful "hollows" found on Mercury and has an etched appearance similar to that found in the crater Tyagaraja. This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 250-meter/pixel (820 feet/pixel) morphology base map or the 1-kilometer/pixel (0.6 miles/pixel) color base map. It is not possible to cover all of Mercury's surface at this high resolution during MESSENGER's one-year mission, but several areas of high scientific interest are generally imaged in this mode each week. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the key science questions that the MESSENGER mission is addressing. During the one-year primary mission, MDIS is scheduled to acquire more than 75,000 images in support of MESSENGER's science goals. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  3. Mercury Flow Through the Mercury-Containing Lamp Sector of the Economy of the United States

    USGS Publications Warehouse

    Goonan, Thomas G.

    2006-01-01

    Introduction: This Scientific Investigations Report examines the flow of mercury through the mercury-containing lamp sector of the U.S. economy in 2001 from lamp manufacture through disposal or recycling. Mercury-containing lamps illuminate commercial and industrial buildings, outdoor areas, and residences. Mercury is an essential component in fluorescent lamps and high-intensity discharge lamps (high-pressure sodium, mercury-vapor, and metal halide). A typical fluorescent lamp is composed of a phosphor-coated glass tube with electrodes located at either end. Only a very small amount of the mercury is in vapor form. The remainder of the mercury is in the form of either liquid mercury metal or solid mercury oxide (mercury oxidizes over the life of the lamp). When voltage is applied, the electrodes energize the mercury vapor and cause it to emit ultraviolet energy. The phosphor coating absorbs the ultraviolet energy, which causes the phosphor to fluoresce and emit visible light. Mercury-containing lamps provide more lumens per watt than incandescent lamps and, as a result, require from three to four times less energy to operate. Mercury is persistent and toxic within the environment. Mercury-containing lamps are of environmental concern because they are widely distributed throughout the environment and are easily broken in handling. The magnitude of lamp sector mercury emissions, estimated to be 2.9 metric tons per year (t/yr), is small compared with the estimated mercury losses of the U.S. coal-burning and chlor-alkali industries, which are about 70 t/yr and about 90 t/yr, respectively.

  4. Trace Elements and Health

    ERIC Educational Resources Information Center

    Pettyjohn, Wayne A.

    1972-01-01

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

  5. Arsenic, cadmium, lead, and mercury in surface soils, Pueblo, Colorado: Implications for population health risk

    USGS Publications Warehouse

    Diawara, D.M.; Litt, J.S.; Unis, D.; Alfonso, N.; Martinez, L.A.; Crock, J.G.; Smith, D.B.; Carsella, J.

    2006-01-01

    Decades of intensive industrial and agricultural practices as well as rapid urbanization have left communities like Pueblo, Colorado facing potential health threats from pollution of its soils, air, water and food supply. To address such concerns about environmental contamination, we conducted an urban geochemical study of the city of Pueblo to offer insights into the potential chemical hazards in soil and inform priorities for future health studies and population interventions aimed at reducing exposures to inorganic substances. The current study characterizes the environmental landscape of Pueblo in terms of heavy metals, and relates this to population distributions. Soil was sampled within the city along transects and analyzed for arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb). We also profiled Pueblo's communities in terms of their socioeconomic status and demographics. ArcGIS 9.0 was used to perform exploratory spatial data analysis and generate community profiles and prediction maps. The topsoil in Pueblo contains more As, Cd, Hg and Pb than national soil averages, although average Hg content in Pueblo was within reported baseline ranges. The highest levels of As concentrations ranged between 56.6 and 66.5 ppm. Lead concentrations exceeded 300 ppm in several of Pueblo's residential communities. Elevated levels of lead are concentrated in low-income Hispanic and African-American communities. Areas of excessively high Cd concentration exist around Pueblo, including low income and minority communities, raising additional health and environmental justice concerns. Although the distribution patterns vary by element and may reflect both industrial and non-industrial sources, the study confirms that there is environmental contamination around Pueblo and underscores the need for a comprehensive public health approach to address environmental threats in urban communities. ?? Springer 2006.

  6. Mercury contamination in Idaho bald eagles, Haliaeetus leucocephalus.

    PubMed

    Bechard, Marc J; Perkins, Dusty N; Kaltenecker, Gregory S; Alsup, Steve

    2009-11-01

    Because mercury contamination is potentially threatening to bald eagle (Haliaeetus leucocephalus) populations, we collected molted feathers at nests to determine the level of contamination in bald eagles in the state of Idaho, USA. Eagle feathers contained measurable amounts of cadmium (Cd), chromium (Cr), selenium (Se), lead (Pb), as well as mercury (Hg). Cadmium, Cr, Se, and Pb levels averaged 0.17, 4.68, 2.02, and 1.29 mg/kg dry weight, respectively, and were at or below concentrations indicated as causing reproductive failure in bald eagles. Mercury contamination was found to be the highest averaging 18.74 mg/kg dry weight. Although a concentration of only 7.5 mg/kg dry weight Hg in bird feathers can cause reduced productivity and even sterility, all of the eagles we sampled bred successfully and the population of bald eagles continues to grow annually throughout the state.

  7. Mercury and other element exposure in tree swallows nesting at low pH and neutral pH lakes in northern Wisconsin USA

    USGS Publications Warehouse

    Custer, Thomas W.; Custer, Christine M.; Thogmartin, Wayne E.; Dummer, Paul M.; Rossmann, Ronald; Kenow, Kevin P.; Meyer, Michael W.

    2012-01-01

    The primary objective of this study was to determine whether tree swallows (Tachycineta bicolor) demonstrate similar responses to lake pH and mercury (Hg) contamination in northern Wisconsin as do common loons (Gavia immer). Similar to common loons, Hg concentrations in the blood of tree swallow nestlings were higher, Hg concentrations in eggs tended to be higher, and egg size tended to be smaller at low (<6.2) pH lakes. In contrast to common loons, tree swallow nestling production was not lower at low pH lakes. Based on modeling associations, Hg concentrations in tree swallow eggs and nestling blood can be used to predict Hg concentrations in common loons without the invasive or destructive sampling of loons. Mean concentrations of cadmium, manganese, and mercury in nestling livers were higher at low pH lakes than neutral pH lakes. Concentrations of cadmium, chromium, mercury, selenium, and zinc were not at toxic levels.

  8. Mercury and other element exposure in tree swallows nesting at low pH and neutral pH lakes in northern Wisconsin USA

    USGS Publications Warehouse

    Custer, T.W.; Custer, Christine M.; Thogmartin, W.E.; Dummer, P.M.; Rossmann, R.; Kenow, K.P.; Meyer, M.W.

    2012-01-01

    The primary objective of this study was to determine whether tree swallows (Tachycineta bicolor) demonstrate similar responses to lake pH and mercury (Hg) contamination in northern Wisconsin as do common loons (Gavia immer). Similar to common loons, Hg concentrations in the blood of tree swallow nestlings were higher, Hg concentrations in eggs tended to be higher, and egg size tended to be smaller at low (<6.2) pH lakes. In contrast to common loons, tree swallow nestling production was not lower at low pH lakes. Based on modeling associations, Hg concentrations in tree swallow eggs and nestling blood can be used to predict Hg concentrations in common loons without the invasive or destructive sampling of loons. Mean concentrations of cadmium, manganese, and mercury in nestling livers were higher at low pH lakes than neutral pH lakes. Concentrations of cadmium, chromium, mercury, selenium, and zinc were not at toxic levels. ?? 2011 Elsevier Ltd. All rights reserved.

  9. Geochemistry of selected mercury mine-tailings in the Parkfield Mercury District, California

    USGS Publications Warehouse

    Rytuba, James J.; Kotlyar, Boris B.; Wilkerson, Gregg; Olson, Jerry

    2001-01-01

    The Parkfield mercury district is located in the southern part of the California Coast Range mercury mineral belt and contains three silica-carbonate-type mercury deposits that have had significant mercury production. Mercury was first produced in the district in 1873, but the main period of production occurred from 1915-1922. Total production from the district is about 5,000 flasks of mercury (a flask equals 76 pounds of mercury) with most production coming from the Patriquin mine (1,875 flasks), and somewhat less from the King (1,600 flasks) and Dawson (1,470 flasks) mines. Several other small prospects and mines occur in the district but only minor production has come from them. In 1969, Phelan Sulphur Company carried out mineral exploration at the King mine and announced the discovery of 55,000 tons of mercury ore with an average grade of 5.2 pounds per ton. The King mine is located on federal land administered by the U.S. Bureau of Land Management. Several other parcels of federal land are present adjacent to other mines and prospects in the Parkfield district. An environmental assessment of mine sites on and adjacent to federal land was carried out to determine the amount of mercury and other trace metals present in mine wastes and in sediments from streams impacted by past mining.

  10. Retention of mercury by salmon

    USGS Publications Warehouse

    Amend, Donald F.

    1970-01-01

    Consuming fish that have been exposed repeatedly to mercury derivatives is a potential public health hazard because fish can accumulate and retain mercury in their tissues (Rucker, 1968). Concern has been expressed in the United States because mercurials have been used extensively in industry and as prophylactic and therapeutic agents in fish hatcheries. Rucker and Amend (1969) showed that yearling rainbow trout (Salmo gairdneri) and chinook salmon (Oncorhynchus tshawytscha) exposed to mercurials accumulated excessive amounts of mercury in many tissues. Further, Rucker and Amend (1969) concluded that wild fish that ate mercury-contaminated fish also could contain high mercury levels. Although mercury was eliminated from most tissues within several months, substantial levels remained in the kidney for more than 33 weeks after the last exposure. Since high levels of mercury can be retained in the kidney for an undetermined time, it is possible that returning adult salmon exposed to mercurials as juveniles could constitute a potential hazard to public health. The purpose of this study was to determine whether such fish contained high residual levels of mercury.

  11. Mercury Isotopes as Proxies to Identify Sources and Environmental Impacts of Mercury in Sphalerites

    PubMed Central

    Yin, Runsheng; Feng, Xinbin; Hurley, James P.; Krabbenhoft, David P.; Lepak, Ryan F.; Hu, Ruizhong; Zhang, Qian; Li, Zhonggen; Bi, Xianwu

    2016-01-01

    During the past few years, evidence of mass independent fractionation (MIF) for mercury (Hg) isotopes have been reported in the Earth’s surface reservoirs, mainly assumed to be formed during photochemical processes. However, the magnitude of Hg-MIF in interior pools of the crust is largely unknown. Here, we reported significant variation in Hg-MIF signature (Δ199Hg: −0.24 ~ + 0.18‰) in sphalerites collected from 102 zinc (Zn) deposits in China, indicating that Hg-MIF can be recorded into the Earth’s crust during geological recycling of crustal material. Changing magnitudes of Hg-MIF signals were observed in Zn deposits with different formations, evidence that Hg isotopes (especially Hg-MIF) can be a useful tracer to identify sources (syngenetic and epigenetic) of Hg in mineral deposits. The average isotopic composition in studied sphalerites (δ202Hgaverage: −0.58‰; Δ199Hgaverage: +0.03‰) may be used to fingerprint Zn smelting activities, one of the largest global Hg emission sources. PMID:26728705

  12. Spatial variation of mercury bioaccumulation in bats of Canada linked to atmospheric mercury deposition.

    PubMed

    Chételat, John; Hickey, M Brian C; Poulain, Alexandre J; Dastoor, Ashu; Ryjkov, Andrei; McAlpine, Donald; Vanderwolf, Karen; Jung, Thomas S; Hale, Lesley; Cooke, Emma L L; Hobson, Dave; Jonasson, Kristin; Kaupas, Laura; McCarthy, Sara; McClelland, Christine; Morningstar, Derek; Norquay, Kaleigh J O; Novy, Richard; Player, Delanie; Redford, Tony; Simard, Anouk; Stamler, Samantha; Webber, Quinn M R; Yumvihoze, Emmanuel; Zanuttig, Michelle

    2018-06-01

    Wildlife are exposed to neurotoxic mercury at locations distant from anthropogenic emission sources because of long-range atmospheric transport of this metal. In this study, mercury bioaccumulation in insectivorous bat species (Mammalia: Chiroptera) was investigated on a broad geographic scale in Canada. Fur was analyzed (n=1178) for total mercury from 43 locations spanning 20° latitude and 77° longitude. Total mercury and methylmercury concentrations in fur were positively correlated with concentrations in internal tissues (brain, liver, kidney) for a small subset (n=21) of little brown bats (Myotis lucifugus) and big brown bats (Eptesicus fuscus), validating the use of fur to indicate internal mercury exposure. Brain methylmercury concentrations were approximately 10% of total mercury concentrations in fur. Three bat species were mainly collected (little brown bats, big brown bats, and northern long-eared bats [M. septentrionalis]), with little brown bats having lower total mercury concentrations in their fur than the other two species at sites where both species were sampled. On average, juvenile bats had lower total mercury concentrations than adults but no differences were found between males and females of a species. Combining our dataset with previously published data for eastern Canada, median total mercury concentrations in fur of little brown bats ranged from 0.88-12.78μg/g among 11 provinces and territories. Highest concentrations were found in eastern Canada where bats are most endangered from introduced disease. Model estimates of atmospheric mercury deposition indicated that eastern Canada was exposed to greater mercury deposition than central and western sites. Further, mean total mercury concentrations in fur of adult little brown bats were positively correlated with site-specific estimates of atmospheric mercury deposition. This study provides the largest geographic coverage of mercury measurements in bats to date and indicates that atmospheric

  13. Arsenic, cadmium, lead, and zinc in the Danville and Springfield coal members (Pennsylvanian) from Indiana

    USGS Publications Warehouse

    Mastalerz, Maria; Drobniak, A.

    2007-01-01

    Arsenic, cadmium, lead, and zinc contents and distributions are discussed in two major Pennsylvanian coal beds in Indiana: the Danville Coal Member and the Springfield Coal Member. Arsenic contents of the Danville and Springfield coals show similar ranges from 0.5 to 43??ppm for the Danville Coal and 1 to 50??ppm for the Springfield Coal, with an average of 12.7??ppm for the Danville and 9.4??ppm for the Springfield Coal. Cadmium concentrations do not exceed 9??ppm, with an average of 0.4 for Danville and 0.7??ppm for the Springfield. Average Pb contents are 21.3 and 6.3??ppm, whereas Zn contents are 101 and 54??ppm for the Danville and the Springfield, respectively. The distribution of these elements varies both laterally and vertically within the coals, as functions of their mineral associations and the time of their emplacement. ?? 2006 Elsevier B.V. All rights reserved.

  14. Temporal and spatial distribution of waterborne mercury in a gold miner's river.

    PubMed

    Picado, Francisco; Bengtsson, Göran

    2012-10-26

    We examined the spatial and temporal (hourly) variation of aqueous concentrations of mercury in a gold miner's river to determine factors that control transport, retention, and export of mercury. The mercury flux was estimated to account for episodic inputs of mercury through mining tailings, variations in flow rate, and the partitioning of mercury between dissolved and particulate phases. Water samples were collected upstream and downstream of two gold mining sites in the Artiguas river, Nicaragua. The samples were analyzed for dissolved and suspended mercury, total solids, dissolved organic carbon, and total iron in water. Water velocity was also measured at the sampling sites. We found that mercury was mainly transported in a suspended phase, with a temporal pattern of diurnal peaks corresponding to the amalgamation schedules at the mining plants. The concentrations decreased with distance from the mining sites, suggesting dilution by tributaries or sedimentation of particle-bound mercury. The lowest total mercury concentrations in the water were less than 0.1 μg l(-1) and the highest concentration was 5.0 μg l(-1). The mercury concentrations are below the present WHO guidelines of 6 μg l(-1) but are considered to lead to a higher risk to aquatic bacteria and fish in the stream than to humans. The aqueous concentrations exceed the hazard endpoints for both groups by a probability of about 1%. Particulate mercury accounted for the largest variation of mercury fluxes, whereas dissolved mercury made up most of the long-range transport along the stream. The estimated total mass of mercury retained due to sedimentation of suspended solids was 2.7 kg per year, and the total mass exported downstream from the mining area was 1.6 kg per year. This study demonstrates the importance of the temporal and spatial resolution of observations in describing the occurrence and fate of mercury in a river affected by anthropogenic activities.

  15. Determination of Zinc, Cadmium, Lead, Copper and Silver Using a Carbon Paste Electrode and a Screen Printed Electrode Modified with Chromium(III) Oxide.

    PubMed

    Koudelkova, Zuzana; Syrovy, Tomas; Ambrozova, Pavlina; Moravec, Zdenek; Kubac, Lubomir; Hynek, David; Richtera, Lukas; Adam, Vojtech

    2017-08-09

    In this study, the preparation and electrochemical application of a chromium(III) oxide modified carbon paste electrode (Cr-CPE) and a screen printed electrode (SPE), made from the same material and optimized for the simple, cheap and sensitive simultaneous determination of zinc, cadmium, lead, copper and the detection of silver ions, is described. The limits of detection and quantification were 25 and 80 µg·L -1 for Zn(II), 3 and 10 µg·L -1 for Cd(II), 3 and 10 µg·L -1 for Pb(II), 3 and 10 µg·L -1 for Cu(II), and 3 and 10 µg·L -1 for Ag(I), respectively. Furthermore, this promising modification was transferred to the screen-printed electrode. The limits of detection for the simultaneous determination of zinc, cadmium, copper and lead on the screen printed electrodes were found to be 350 µg·L -1 for Zn(II), 25 µg·L -1 for Cd(II), 3 µg·L -1 for Pb(II) and 3 µg·L -1 for Cu(II). Practical usability for the simultaneous detection of these heavy metal ions by the Cr-CPE was also demonstrated in the analyses of wastewaters.

  16. Determination of Zinc, Cadmium, Lead, Copper and Silver Using a Carbon Paste Electrode and a Screen Printed Electrode Modified with Chromium(III) Oxide

    PubMed Central

    Koudelkova, Zuzana; Syrovy, Tomas; Ambrozova, Pavlina; Moravec, Zdenek; Kubac, Lubomir; Hynek, David; Adam, Vojtech

    2017-01-01

    In this study, the preparation and electrochemical application of a chromium(III) oxide modified carbon paste electrode (Cr-CPE) and a screen printed electrode (SPE), made from the same material and optimized for the simple, cheap and sensitive simultaneous determination of zinc, cadmium, lead, copper and the detection of silver ions, is described. The limits of detection and quantification were 25 and 80 µg·L−1 for Zn(II), 3 and 10 µg·L−1 for Cd(II), 3 and 10 µg·L−1 for Pb(II), 3 and 10 µg·L−1 for Cu(II), and 3 and 10 µg·L−1 for Ag(I), respectively. Furthermore, this promising modification was transferred to the screen-printed electrode. The limits of detection for the simultaneous determination of zinc, cadmium, copper and lead on the screen printed electrodes were found to be 350 µg·L−1 for Zn(II), 25 µg·L−1 for Cd(II), 3 µg·L−1 for Pb(II) and 3 µg·L−1 for Cu(II). Practical usability for the simultaneous detection of these heavy metal ions by the Cr-CPE was also demonstrated in the analyses of wastewaters. PMID:28792450

  17. Zinc status in South Asian populations--an update.

    PubMed

    Akhtar, Saeed

    2013-06-01

    This article attempts to highlight the prevalence of zinc deficiency and its health and economic consequences in South Asian developing countries and to shed light on possible approaches to combating zinc deficiency. A computer-based search was performed on PubMed, Google, and ScienceDirect.com to retrieve relevant scientific literature published between 2000 and 2012. The search yielded 194 articles, of which 71 were culled. Studies were further screened on the basis of population groups, age and sex, pregnancy, and lactation. The most relevant articles were included in the review. Cutoffs for serum zinc concentration defined for zinc deficiency were 65 microg/dL for males and females aged < 10 years, 66 microg/dL for non-pregnant females, and 70 microg/dL for males aged > or = 10 years. Population segments from rural and urban areas of South Asian developing countries were included in the analysis. They comprised pregnant and lactating women, preschool and school children. The analysis reveals that zinc deficiency is high among children, pregnant and lactating women in India, Pakistan, Bangladesh, Sri Lanka, and Nepal. Diarrhoea has been established as a leading cause to intensify zinc deficiency in Bangladesh. Little has been done in Sri Lanka and Nepal to estimate the prevalence of zinc deficiency precisely. A substantial population segment of the South Asian developing countries is predisposed to zinc deficiency which is further provoked by increased requirements for zinc under certain physiological conditions. Supplementation, fortification, and dietary diversification are the most viable strategies to enhancing zinc status among various population groups.

  18. [Amalgam. IV. Metabolism of mercury].

    PubMed

    Gladys, S; van Meerbeek, B; Vanherle, G; Lambrechts, P

    1993-04-01

    After absorption in the body by four ways, each type of mercury undergoes a specific metabolism. Elementary mercury as mercury vapour becomes rapidly oxidized to Hg2+ and, afterwards, is metabolized as an inorganic mercurial compound. From the blood circulation mercury reaches target organs like the kidneys, the central nervous system, the liver and the hypophysis, in which mercury accumulates. The retention time varies by organ and is longest in the brain. Mercury is mainly eliminated with urine and faeces, to a lesser degree with transpiration and mother's milk and sometimes by respiration.

  19. Method development estimating ambient mercury concentration from monitored mercury wet deposition

    NASA Astrophysics Data System (ADS)

    Chen, S. M.; Qiu, X.; Zhang, L.; Yang, F.; Blanchard, P.

    2013-05-01

    Speciated atmospheric mercury data have recently been monitored at multiple locations in North America; but the spatial coverage is far less than the long-established mercury wet deposition network. The present study describes a first attempt linking ambient concentration with wet deposition using Beta distribution fitting of a ratio estimate. The mean, median, mode, standard deviation, and skewness of the fitted Beta distribution parameters were generated using data collected in 2009 at 11 monitoring stations. Comparing the normalized histogram and the fitted density function, the empirical and fitted Beta distribution of the ratio shows a close fit. The estimated ambient mercury concentration was further partitioned into reactive gaseous mercury and particulate bound mercury using linear regression model developed by Amos et al. (2012). The method presented here can be used to roughly estimate mercury ambient concentration at locations and/or times where such measurement is not available but where wet deposition is monitored.

  20. Determination of mercurous chloride and total mercury in mercury ores

    USGS Publications Warehouse

    Fahey, J.J.

    1937-01-01

    A method for the determination of mercurous chloride and total mercury on the same sample is described. The mercury minerals are volatilized in a glass tube and brought into intimate contact with granulated sodium carbonate. The chlorine is fixed as sodium chloride, determined with silver nitrate, and computed to mercurous chloride. The mercury is collected on a previously weighed gold coil and weighed.

  1. Recreational Reuse of Waste Disposal Sites: Chanute Air Force Base, Illinois.

    DTIC Science & Technology

    1983-11-01

    Nickel Endrin Lead Heptachlor Zinc Heptachlor epoxide Mercury Lindane Silver MethoxychIor Barium Toxaphene Parathion Lagoon and Monitoring Well Water...Gleditisa T. I. Imperial Imperial Honey Locust Platanus acerifolia Bloodgood London Planetree Ulmus parvifolia True Chinese Elm (Populus alba) White

  2. The Role of Blood Lead, Cadmium, Zinc and Copper in Development and Severity of Acne Vulgaris in a Nigerian Population.

    PubMed

    Ikaraoha, C I; Mbadiwe, N C; Anyanwu, C J; Odekhian, J; Nwadike, C N; Amah, H C

    2017-04-01

    Acne vulgaris is a very common skin disorder affecting human beings. There is a paucity of report on the role of heavy metals-lead (Pb) and cadmium (Cd)-globally, and trace metals-zinc (Zn) and copper (Cd)-particularly in Nigeria in the development/severity of acne vulgaris. This study is aimed to determine the blood levels of some heavy metals-cadmium and lead-and trace metals-zinc and copper-in acne vulgaris sufferers in a Nigerian population. Venous blood samples were collected from a total number of 90 non-obese female subjects consisting of 30 mild, 30 moderate and 30 severe acne vulgaris sufferers for blood Cd, Pb, Cu and Zn determination. They were age-matched with 60 females without acne vulgaris who served as the control subjects. Acne sufferers had significantly higher blood Cd and Pb (P = 0.0143 and P = 0.0001 respectively) and non-significantly different blood levels of Cu and Zn (P = 0.910 and P = 0.2140 respectively) compared to controls. There were significant progressive increases in blood levels of Cd and Pb (P = 0.0330 and P = 0.0001 respectively) and non-significant differences in the mean blood level of Cu and Zn (P = 0.1821 and P = 0.2728 respectively) from mild to moderate and severe acne vulgaris sufferers. Increases in blood Cd and Pb may play critical roles in the pathogenesis/severity of acne vulgaris, while Cu and Zn seem to play less significant roles in the development of this disorder in this environment.

  3. Mortality of Sardinian lead and zinc miners: 1960-88.

    PubMed Central

    Cocco, P L; Carta, P; Belli, S; Picchiri, G F; Flore, M V

    1994-01-01

    The mortality of 4740 male workers of two lead and zinc mines was followed up from 1960 to 1988. Exposure to respirable dust was comparable in the two mines, but the median concentration of silica in respirable dust was 10-fold higher in mine B (12.8%) than in mine A (1.2%), but the mean annual exposure to radon daughters in underground workplaces differed in the opposite direction (mine A: 0.13 working levels (WL), mine B: 0.011 WL). Total observed deaths (1205) were similar to expected figures (1156.3) over a total of 119 390.5 person-years at risk. Underground workers of mine B had significant increases in risk of pulmonary tuberculosis (SMR 706, 95% confidence interval (95% CI) 473-1014) and non-malignant respiratory diseases (SMR 518; 95% CI 440-1606), whereas the only significant excess at mine A was for non-malignant respiratory diseases (SMR 246; 95% CI 191-312). Total cancer and lung cancer mortality did not exceed the expectation in the two mines combined. A 15% excess mortality for lung cancer, increased up to an SMR 204 (95% CI 89-470) for subjects employed > or = 26 years, was, however, found among underground workers in mine A who on the average experienced an exposure to radon daughters 10-fold higher than those of mine B. By contrast, despite their higher exposure to silica, mine B underground workers experienced a lower than expected lung cancer mortality. A ninefold increase in risk of peritoneal and retroperitoneal cancer combined was also found among underground workers of mine A (SMR 917; 95% CI 250-2347; based on four deaths). A causal association with workplace exposures is unlikely, however, as the SMR showed an inverse trend by duration of employment. These findings are consistent with low level exposure to radon daughters as a risk factor for lung cancer among metal miners. Exposure to silica at the levels estimated for the mine B underground environment did not increase the risk of lung cancer. PMID:8000492

  4. Occurrence of silver minerals in a silver-rich pocket in the massive sulfide zinc-lead ores in the Edwards mine, New York

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Serviss, C.R.; Grout, C.M.; Hagni, R.D.

    1985-01-01

    Ore microscopic examination of uncommon silver-rich ores from the Edwards mine has detected three silver minerals, native silver, freibergite, and argentite, that were previously unreported in the literature from the Balmat-Edwards district. The zinc-lead ore deposits of the Balmat-Edwards District in northern New York are composed of very coarse-grained massive sulfides, principally sphalerite, galena, and pyrite. The typical ores contain small amounts of silver in solid solution galena. Galena concentrates produced from those ores have contained an average of 15 ounces of silver per ton of 60% lead concentrates. In contrast to the typical ore a silver-rich pocket, that measuredmore » three feet by three feet on the vertical mine face and was the subject of this study, contained nearly 1% silver in a zinc ore. Ore microscopic study shows that this ore is especially characterized by abundant, relatively fine-grained chalcopyrite with anhedral pyrite inclusions. Fine-grained sphalerite, native silver, argentite, freibergite and arsenopyrite occur in association with the chalcopyrite and as fracture-fillings in gangue minerals. Geochemically anomalous amounts of tin, barium, chromium, and nickel also are present in the silver-rich pocket. The silver-rich pocket may mark the locus of an early feeder vent or alternatively it may record a hydrothermal event that was superimposed upon the event responsible for the metamorphic ore textures.« less

  5. 40 CFR 421.252 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0.546 0.260 Mercury 0.325 0.130 Silver 0.533 0.221 Zinc 1.898 0.793 Gold 0.130 Oil....164 0.068 Zinc 0.584 0.244 Gold 0.040 Oil and grease 8.000 4.800 Total suspended solids 16.400 7.800 p...

  6. 40 CFR 421.252 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0.546 0.260 Mercury 0.325 0.130 Silver 0.533 0.221 Zinc 1.898 0.793 Gold 0.130 Oil....164 0.068 Zinc 0.584 0.244 Gold 0.040 Oil and grease 8.000 4.800 Total suspended solids 16.400 7.800 p...

  7. 40 CFR 421.252 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0.546 0.260 Mercury 0.325 0.130 Silver 0.533 0.221 Zinc 1.898 0.793 Gold 0.130 Oil....164 0.068 Zinc 0.584 0.244 Gold 0.040 Oil and grease 8.000 4.800 Total suspended solids 16.400 7.800 p...

  8. Methyl mercury, but not inorganic mercury, associated with higher blood pressure during pregnancy.

    PubMed

    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.

  9. Group 13 ligand supported heavy-metal complexes: first structural evidence for gallium-lead and gallium-mercury bonds.

    PubMed

    Prabusankar, Ganesan; Gemel, Christian; Winter, Manuela; Seidel, Rüdiger W; Fischer, Roland A

    2010-05-25

    Heavy-metal complexes of lead and mercury stabilized by Group 13 ligands were derived from the oxidative addition of Ga(ddp) (ddp=HC(CMeNC(6)H(3)-2,6-iPr(2))(2), 2-diisopropylphenylamino-4-diisopropyl phenylimino-2-pentene) with corresponding metal precursors. The reaction of Me(3)PbCl and Ga(ddp) afforded compound [{(ddp)Ga(Cl)}PbMe(3)] (1) composed of Ga-Pb(IV) bonds. In addition, the monomeric plumbylene-type compound [{(ddp)Ga(OSO(2)CF(3))}(2)Pb(thf)] (2a) with an unsupported Ga-Pb(II)-Ga linkage was obtained by the reaction of [Pb(OSO(2)CF(3))(3)] with Ga(ddp) (2 equiv). Compound 2a falls under the rare example of a discrete plumbylene-type compound supported by a nonclassical ligand. Interesting structural changes were observed when [Pb(OSO(2)CF(3))(3)]2.H(2)O was treated with Ga(ddp) in a 1:2 ratio to yield [{(ddp)Ga(mu-OSO(2)CF(3))}(2)(OH(2))Pb] (2b) at below -10 degrees C. Compound 2b consists of a bent Ga-Pb-Ga backbone with a bridging triflate group between the Ga-Pb bond and a weakly interacting water molecule at the gallium center. Similarly, the reaction of mercury thiolate Hg(SC(6)F(5)) with Ga(ddp) (2 equiv) produced the bimetallic homoleptic compounds anti-[{(ddp)Ga(SC(6)F(5))}(2)Hg] (3a) and gauche-[{(ddp)Ga(SC(6)F(5))}(2)Hg] (3b), respectively, with a linear Ga-Hg-Ga linkage. Compounds 1-3 were structurally characterized and these are the first examples of compounds comprised of Ga-Pb(II), Ga-Pb(IV), and Ga-Hg bonds.

  10. The Impact of the Major Baltic Inflow of December 2014 on the Mercury Species Distribution in the Baltic Sea.

    PubMed

    Kuss, Joachim; Cordes, Florian; Mohrholz, Volker; Nausch, Günther; Naumann, Michael; Krüger, Siegfried; Schulz-Bull, Detlef E

    2017-10-17

    The Baltic Sea is a marginal sea characterized by stagnation periods of several years. Oxygen consumption in its deep waters leads to the buildup of sulfide from sulfate reduction. Some of the microorganisms responsible for these processes also transform reactive ionic mercury to neurotoxic methylmercury. Episodic inflows of oxygenated saline water from the North Sea temporally re-establish oxic life in deep waters of the Baltic Sea. Thus, this sea is an especially important region to better understand mercury species distributions in connection with variable redox conditions. Mercury species were measured on three Baltic Sea campaigns, during the preinflow, ongoing inflow, and subsiding inflow of water, respectively, to the central basin. The inflowing water caused the removal of total mercury by 600 nmol m -2 and of methylmercury by 214 nmol m -2 in the Gotland Deep, probably via attachment of the mercury compounds to sinking particles. It appears likely that the consequences of the oxygenation of Baltic Sea deep waters, which are the coprecipitation of mercury species and the resettlement of the oxic deep waters, could lead to the enhanced transfer of accumulated mercury and methylmercury to the planktonic food chain and finally to fish.

  11. Assessment of metals pollution on agricultural soil surrounding a lead-zinc mining area in the Karst region of Guangxi, China.

    PubMed

    Zhang, Chaolan; Li, Zhongyi; Yang, Weiwei; Pan, Liping; Gu, Minghua; Lee, DoKyoung

    2013-06-01

    Soil samples were collected on farmland in a lead-zinc mining area in the Karst region of Guangxi, China. The contamination of the soil by eight metals (Cd, Hg, As, Cu, Pb, Cr, Zn, Ni) was determined. Among all these metals, Cd is the most serious pollutant in this area. Zn, Hg as well asPb can also be measured at high levels, which may affect the crop production. All other metals contributed marginally to the overall soil contamination. Besides the evaluation of single metals, the Nemerow synthetic index indicated that the soil is not suitable for agricultural use.

  12. Zinc Levels Modulate Lifespan through Multiple Longevity Pathways in Caenorhabditis elegans

    PubMed Central

    Kumar, Jitendra; Barhydt, Tracy; Awasthi, Anjali; Lithgow, Gordon J.; Killilea, David W.; Kapahi, Pankaj

    2016-01-01

    Zinc is an essential trace metal that has integral roles in numerous biological processes, including enzymatic function, protein structure, and cell signaling pathways. Both excess and deficiency of zinc can lead to detrimental effects on development and metabolism, resulting in abnormalities and disease. We altered the zinc balance within Caenorhabditis elegans to examine how changes in zinc burden affect longevity and healthspan in an invertebrate animal model. We found that increasing zinc levels in vivo with excess dietary zinc supplementation decreased the mean and maximum lifespan, whereas reducing zinc levels in vivo with a zinc-selective chelator increased the mean and maximum lifespan in C. elegans. We determined that the lifespan shortening effects of excess zinc required expression of DAF-16, HSF-1 and SKN-1 proteins, whereas the lifespan lengthening effects of the reduced zinc may be partially dependent upon this set of proteins. Furthermore, reducing zinc levels led to greater nuclear localization of DAF-16 and enhanced dauer formation compared to controls, suggesting that the lifespan effects of zinc are mediated in part by the insulin/IGF-1 pathway. Additionally, zinc status correlated with several markers of healthspan in worms, including proteostasis, locomotion and thermotolerance, with reduced zinc levels always associated with improvements in function. Taken together, these data support a role for zinc in regulating both development and lifespan in C. elegans, and that suggest that regulation of zinc homeostasis in the worm may be an example of antagonistic pleiotropy. PMID:27078872

  13. Mercury, Cadmium, and Lead Levels in Human Placenta: A Systematic Review

    PubMed Central

    Esteban-Vasallo, María D.; Aragonés, Nuria; Pollan, Marina; López-Abente, Gonzalo

    2012-01-01

    Background: Placental tissue may furnish information on the exposure of both mother and fetus. Mercury (Hg), cadmium (Cd), and lead (Pb) are toxicants of interest in pregnancy because they are associated with alterations in child development. Objectives: The aim of this study was to summarize the available information regarding total Hg, Cd, and Pb levels in human placenta and possible related factors. Methods: We performed a systematic search of PubMed/MEDLINE, EMBASE, Lilacs, OSH, and Web of Science for original papers on total Hg, Cd, or Pb levels in human placenta that were published in English or Spanish (1976–2011). Data on study design, population characteristics, collection and analysis of placenta specimens, and main results were extracted using a standardized form. Results: We found a total of 79 papers (73 different studies). Hg, Cd, and Pb levels were reported in 24, 46, and 46 studies, respectively. Most studies included small convenience samples of healthy pregnant women. Studies were heterogeneous regarding populations selected, processing of specimens, and presentation of results. Hg concentrations > 50 ng/g were found in China (Shanghai), Japan, and the Faroe Islands. Cd levels ranged from 1.2 ng/g to 53 ng/g and were highest in the United States, Japan, and Eastern Europe. Pb showed the greatest variability, with levels ranging from 1.18 ng/g in China (Shanghai) to 500 ng/g in a polluted area of Poland. Conclusion: The use of the placenta as a biomarker to assess heavy metals exposure is not properly developed because of heterogeneity among the studies. International standardized protocols are needed to enhance comparability and increase the usefulness of this promising tissue in biomonitoring studies. PMID:22591711

  14. Zinc Modulates Nanosilver-Induced Toxicity in Primary Neuronal Cultures.

    PubMed

    Ziemińska, Elżbieta; Strużyńska, Lidia

    2016-02-01

    Silver nanoparticles (NAg) have recently become one of the most commonly used nanomaterials. Since the ability of nanosilver to enter the brain has been confirmed, there has been a need to investigate mechanisms of its neurotoxicity. We previously showed that primary neuronal cultures treated with nanosilver undergo destabilization of calcium homeostasis via a mechanism involving glutamatergic NMDA receptors. Considering the fact that zinc interacts with these receptors, the aim of the present study was to examine the role of zinc in mechanisms of neuronal cell death in primary cultures. In cells treated with nanosilver, we noted an imbalance between extracellular and intracellular zinc levels. Thus, the influence of zinc deficiency and supplementation on nanosilver-evoked cytotoxicity was investigated by treatment with TPEN (a chelator of zinc ions), or ZnCl(2), respectively. Elimination of zinc leads to complete death of nanosilver-treated CGCs. In contrast, supplementation with ZnCl(2) increases viability of CGCs in a dose-dependent manner. Addition of zinc provided protection against the extra/intracellular calcium imbalance in a manner similar to MK-801, an antagonist of NMDA receptors. Zinc chelation by TPEN decreases the mitochondrial potential and dramatically increases the rate of production of reactive oxygen species. Our results indicate that zinc supplementation positively influences nanosilver-evoked changes in CGCs. This is presumed to be due to an inhibitory effect on NMDA-sensitive calcium channels.

  15. To Mercury dynamics

    NASA Astrophysics Data System (ADS)

    Barkin, Yu. V.; Ferrandiz, J. M.

    Present significance of the study of rotation of Mercury considered as a core-mantle system arises from planned Mercury missions. New high accurate data on Mercury's structure and its physical fields are expected from BepiColombo mission (Anselmi et al., 2001). Investigation of resonant rotation of Mercury, begun by Colombo G. (1966), will play here main part. New approaches to the study of Mercury dynamics and the construction of analytical theory of its resonant rotation are suggested. Within these approaches Mercury is considered as a system of two non-spherical interacting bodies: a core and a mantle. The mantle of Mercury is considered as non-spherical, rigid (or elastic) layer. Inner shell is a liquid core, which occupies a large ellipsoidal cavity of Mercury. This Mercury system moves in the gravitational field of the Sun in resonant traslatory-rotary regime of the resonance 3:2. We take into account only the second harmonic of the force function of the Sun and Mercury. For the study of Mercury rotation we have been used specially designed canonical equations of motion in Andoyer and Poincare variables (Barkin, Ferrandiz, 2001), more convenient for the application of mentioned methods. Approximate observational and some theoretical evaluations of the two main coefficients of Mercury gravitational field J_2 and C22 are known. From observational data of Mariner-10 mission were obtained some first evaluations of these coefficients: J_2 =(8± 6)\\cdot 10-5(Esposito et al., 1977); J_2 =(6± 2)\\cdot 10-5and C22 =(1.0± 0.5)\\cdot 10-5(Anderson et al., 1987). Some theoretical evaluation of ratio of these coefficients has been obtained on the base of study of periodic motions of the system of two non-spherical gravitating bodies (Barkin, 1976). Corresponding values of coefficients consist: J_2 =8\\cdot 10-5and C22 =0.33\\cdot 10-5. We have no data about non-sphericity of inner core of Mercury. Planned missions to Mercury (BepiColombo and Messenger) promise to

  16. Assessment of semen function and lipid peroxidation among lead exposed men

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kasperczyk, Aleksandra; Kasperczyk, Slawomir; Horak, Stanislaw

    The study population included healthy, fertile men, employees of Zinc and Lead Metalworks (n = 63). Workers exposed to lead were divided into two groups: a group with moderate exposure to lead (ME) - blood lead level (PbB) 25-40 {mu}g/dl and a group with high exposure to lead (HE) PbB = 40-81 {mu}g/dl. The control group consisted of office workers with no history of occupational exposure to lead. Evaluation of lead, cadmium and zinc level in blood and seminal plasma, zinc protoporphyrin in blood (ZPP), 5-aminolevulinic acid in urine (ALA), malondialdehyde (MDA) in seminal plasma and sperm analysis were performed.more » No differences were noted in the concentration of cadmium and zinc in blood and seminal plasma in the study population. Lipid peroxidation in seminal plasma, represented as MDA concentration, significantly increased by about 56% in the HE group and the percentage of motile sperm cells after 1 h decreased by about 34% in comparison to the control group. No statistically significant correlation between other parameters of sperm analysis and lead exposure parameters nor between lead, cadmium and zinc concentration in blood and seminal plasma were found. A positive association between lead intoxication parameters (PbB, ZPP, lead seminal plasma) and MDA concentration in sperm plasma and inverse correlation with sperm cells motility (PbB, ZPP) was found. An increased concentration of MDA was accompanied by a drop in sperm cells motility. In conclusion, we report that high exposure to lead causes a decrease of sperm motility in men most likely as a result of increased lipid peroxidation, especially if the level in the blood surpasses the concentration of 40 {mu}g/dl.« less

  17. Ices on Mercury: Chemistry of volatiles in permanently cold areas of Mercury's north polar region

    NASA Astrophysics Data System (ADS)

    Delitsky, M. L.; Paige, D. A.; Siegler, M. A.; Harju, E. R.; Schriver, D.; Johnson, R. E.; Travnicek, P.

    2017-01-01

    OH, CH3NH2, SO, SO2, SO3, OCS, H2S, CH3SH, even BxHy. Three types of radiation processing mechanisms may be at work in the ices: (1) Impact/dissociation, (2) Ion implantation and (3) Nuclear recoil (hot atom chemistry). Magnetospheric energy sources dominate the radiation effects. Total energy fluxes of photons, SEPs and GCRs are all around two or more orders of magnitude less than the fluxes from magnetospheric energy sources (in the focused cusp particles). However, SEPs and GCRs cause chemical processing at greater depths than other particles leading to thicker organic layers. Processing of polar volatiles on Mercury would be somewhat different from that on the Moon because Mercury has a magnetic field while the Moon does not. The channeled flux of charged particles through these magnetospheric cusps is a chemical processing mechanism unique to Mercury as compared to other airless bodies.

  18. Mercury as the Unaccreted Projectile: Thermal Consequences

    NASA Astrophysics Data System (ADS)

    Asphaug, Erik; Gabriel, Travis; Jackson, Alan; Perera, Viranga

    2017-10-01

    Mercury retained substantial volatiles during its formation, in far greater proportion than the Moon, despite losing ~2/3 of its rocky mantle. Its volatile-rich geochemistry would contraindicate a giant impact because it would drive away the volatiles, as in the hypothesis for the Moon. However, the thermal consequences of Mercury formation vary considerably between the two giant impact scenarios, ‘direct hit’ (DH; Benz et al. 1989) and ‘hit and run’ (HR; Asphaug and Reufer 2014). Each begins with a differentiated chondritic proto-Mercury (PM) a bit larger than Mars. In DH, PM gets eroded by a very energetic impactor half its mass, at ~6-7 times the escape velocity. To remove half of PM’s mantle, the post-impact target gets completely shock-vaporized and is sheared apart into space. The bound remnant in DH would experience a comparable deposition of shock enthalpy, as in Moon formation, and would expand into a much larger volume of heliocentric space, leading to a dry planet. The bound remnant will go on to re-accrete much of the silicate mantle that it just lost, another challenge for DH. In HR, PM is the projectile that slams into a terrestrial planet twice its size (proto-Venus or proto-Earth). For typical impact angle and speed, a typical outcome is to ‘bounce”. But for HR to explain Mercury, PM must avoid accretion every time it encounters the target, until it is scattered or migrates away (or is accreted, in which case there is no Mercury), leading to multi-HR scenarios. Tides are intense in HR because the projectile grazes the target core; gravity does most of the work of mantle stripping. Shocks play a secondary role. Whereas in DH the impactor blasts the target inside-out, in HR the runner emerges relatively unshocked, and undispersed except for losing the gravitationally-unbound material. HR is a mechanism for collecting low-shocked remnants, because the intensely shocked material ends up bound to the target or escaping to heliocentric space

  19. Inhibition of acetylcholinesterase activity in the central nervous system of the red swamp crayfish, Procambarus clarkii, by mercury, cadmium, and lead

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Devi, M.; Fingerman, M.

    The toxicological, physiological and biochemical responses of aquatic crustaceans to heavy metals have been reported by several investigators. Levels of glucose, lactic acid, sodium, potassium, aspartate aminotransferase and alanine aminotransferase in the blood of the crab Scylla serrata increased, while glycogen levels in hepatopancreas and muscle decreased after a four-week exposure to mercuric chloride. In fiddler crab, Uca pugilator, enzyme activity was observed to decrease in the hepatopancreas but increased in abdominal muscle after 48 hr cadmium exposure. In the red swamp crayfish, Procambarus clarkii, exposed for 96 hr to cadmium, glutahione (GSH) level and GSH S-transferase activity deceased inmore » the midgut. In crayfish Astacus astacus exposed to sublethal concentrations of lead and cadmium, oxidative enzyme (succine dehydrogenase and NADPH-cytochrome P450 reductase) activities in gills and hepatopancrease decreased. Acetylcholinesterase (AChE) inhibition by organophosphates and organocarbamates in various crustaceans has bee reported. In vivo cadmium exposure caused increases in esterase activities, but mercury exposure decreases these activities in the hepatopancreas of the shrimp Callianassa tyrrhena. The freshwater crab, Barytelphusa guerini, exposed to 0.6 ppm cadmium showed reduced oxygen consumption throughout the experiment whereas AChE activity increased after 4 days but decreased after 15 days. The authors wanted to determine the effects of cadmium, lead and mercury on AChE activity in central nervous tissue of Procambarus clarkii. This enzyme has the potential for serving both as a biochemical indicator of toxic stress and a sensitive parameter for testing water for the presence of toxicants. These three biologically silent metals have, according to Schweinsberg and Karsa great toxicological significance to humans because their use is widespread. 14 refs., 4 figs.« less

  20. Near Global Mosaic of Mercury

    NASA Astrophysics Data System (ADS)

    Becker, K. J.; Robinson, M. S.; Becker, T. L.; Weller, L. A.; Turner, S.; Nguyen, L.; Selby, C.; Denevi, B. W.; Murchie, S. L.; McNutt, R. L.; Solomon, S. C.

    2009-12-01

    the accuracy of pointing knowledge and reduces overall registration errors between adjacent images. The net effect of these improvements is an overall offset of up to 10 km in some locations across the mosaic. In addition, the radiometric calibration process for the NAC has been improved to yield a better dynamic range across the mosaic by 20%. The new global mosaic of Mercury will be used in scientific analysis and aid in planning observation sequences leading up to and including orbit insertion of the MESSENGER spacecraft in 2011.

  1. Evaluation of blood zinc, calcium and blood lead levels among children aged 1-36 months.

    PubMed

    Ji, Xiaojun; He, Hong; Ren, Lisheng; Liu, Ji; Han, Chunhua

    2014-09-01

    Early childhood lead exposure is associated with numerous adverse health effects. Biomonitoring among susceptible populations, such as children, has not been previously conducted. The aim of the study is to evaluate the blood lead (Pb) and total blood calcium (Ca) levels; blood zinc (Zn) levels. A cross-sectional study was designed to collect healthy children age 1- 36 months (Mean ± SD: 1.5 ± 0.6 age, 60% boys) in the study from January 2010 to September 2011. The overall mean blood Pb levels were 42.18 ± 12.13 μg/L, the overall mean blood Zn and total blood Ca concentrations were 62.18 ± 12.33 μmol/L and 1.78 ± 0.13 mmol/L, respectively. The prevalence of elevated blood Pb levels in all children was 1.3%. A significant difference was found between female and male subjects for the blood Pb and Zn. After controlling for gender and age, there was a weak positive correlation between total blood Ca and Zn level. The blood Pb levels had a significant negative correlation with total blood Ca level after adjusting for age and gender, and these findings suggest that Pb had effect on positive blood Zn and total blood Ca levels; parents should pay more attention to the nutrition of girls. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  2. 40 CFR 63.10885 - What are my management practices for metallic scrap and mercury switches?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-consumer automotive body scrap, post-consumer engine blocks, post-consumer oil filters, oily turnings, lead... suppliers throughout the scrap supply chain the need to promote the removal of mercury switches from end-of... the scrap supply chain the need to promote the removal or mercury switches from end-of-life vehicles...

  3. 40 CFR 63.10885 - What are my management practices for metallic scrap and mercury switches?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-consumer automotive body scrap, post-consumer engine blocks, post-consumer oil filters, oily turnings, lead... suppliers throughout the scrap supply chain the need to promote the removal of mercury switches from end-of... the scrap supply chain the need to promote the removal or mercury switches from end-of-life vehicles...

  4. 40 CFR 63.10885 - What are my management practices for metallic scrap and mercury switches?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-consumer automotive body scrap, post-consumer engine blocks, post-consumer oil filters, oily turnings, lead... suppliers throughout the scrap supply chain the need to promote the removal of mercury switches from end-of... the scrap supply chain the need to promote the removal or mercury switches from end-of-life vehicles...

  5. Removal of Mercury from Chloralkali Electrolysis Wastewater by a Mercury-Resistant Pseudomonas putida Strain

    PubMed Central

    von Canstein, H.; Li, Y.; Timmis, K. N.; Deckwer, W.-D.; Wagner-Döbler, I.

    1999-01-01

    A mercury-resistant bacterial strain which is able to reduce ionic mercury to metallic mercury was used to remediate in laboratory columns mercury-containing wastewater produced during electrolytic production of chlorine. Factory effluents from several chloralkali plants in Europe were analyzed, and these effluents contained total mercury concentrations between 1.6 and 7.6 mg/liter and high chloride concentrations (up to 25 g/liter) and had pH values which were either acidic (pH 2.4) or alkaline (pH 13.0). A mercury-resistant bacterial strain, Pseudomonas putida Spi3, was isolated from polluted river sediments. Biofilms of P. putida Spi3 were grown on porous carrier material in laboratory column bioreactors. The bioreactors were continuously fed with sterile synthetic model wastewater or nonsterile, neutralized, aerated chloralkali wastewater. We found that sodium chloride concentrations up to 24 g/liter did not inhibit microbial mercury retention and that mercury concentrations up to 7 mg/liter could be treated with the bacterial biofilm with no loss of activity. When wastewater samples from three different chloralkali plants in Europe were used, levels of mercury retention efficiency between 90 and 98% were obtained. Thus, microbial mercury removal is a potential biological treatment for chloralkali electrolysis wastewater. PMID:10583977

  6. Investigation on mercury reemission from limestone-gypsum wet flue gas desulfurization slurry.

    PubMed

    Chen, Chuanmin; Liu, Songtao; Gao, Yang; Liu, Yongchao

    2014-01-01

    Secondary atmospheric pollutions may result from wet flue gas desulfurization (WFGD) systems caused by the reduction of Hg(2+) to Hg(0) and lead to a damping of the cobenefit mercury removal efficiency by WFGD systems. The experiment on Hg(0) reemission from limestone-gypsum WFGD slurry was carried out by changing the operating conditions such as the pH, temperature, Cl(-) concentrations, and oxygen concentrations. The partitioning behavior of mercury in the solid and liquid byproducts was also discussed. The experimental results indicated that the Hg(0) reemission rate from WFGD slurry increased as the operational temperatures and pH values increased. The Hg(0) reemission rates decreased as the O2 concentration of flue gas and Cl(-) concentration of WFGD slurry increased. The concentrations of O2 in flue gas have an evident effect on the mercury retention in the solid byproducts. The temperature and Cl(-) concentration have a slight effect on the mercury partitioning in the byproducts. No evident relation was found between mercury retention in the solid byproducts and the pH. The present findings could be valuable for industrial application of characterizing and optimizing mercury control in wet FGD systems.

  7. Investigation on Mercury Reemission from Limestone-Gypsum Wet Flue Gas Desulfurization Slurry

    PubMed Central

    Liu, Songtao; Liu, Yongchao

    2014-01-01

    Secondary atmospheric pollutions may result from wet flue gas desulfurization (WFGD) systems caused by the reduction of Hg2+ to Hg0 and lead to a damping of the cobenefit mercury removal efficiency by WFGD systems. The experiment on Hg0 reemission from limestone-gypsum WFGD slurry was carried out by changing the operating conditions such as the pH, temperature, Cl− concentrations, and oxygen concentrations. The partitioning behavior of mercury in the solid and liquid byproducts was also discussed. The experimental results indicated that the Hg0 reemission rate from WFGD slurry increased as the operational temperatures and pH values increased. The Hg0 reemission rates decreased as the O2 concentration of flue gas and Cl− concentration of WFGD slurry increased. The concentrations of O2 in flue gas have an evident effect on the mercury retention in the solid byproducts. The temperature and Cl− concentration have a slight effect on the mercury partitioning in the byproducts. No evident relation was found between mercury retention in the solid byproducts and the pH. The present findings could be valuable for industrial application of characterizing and optimizing mercury control in wet FGD systems. PMID:24737981

  8. Improved zinc electrode and rechargeable zinc-air battery

    DOEpatents

    Ross, P.N. Jr.

    1988-06-21

    The invention comprises an improved rechargeable zinc-air cell/battery having recirculating alkaline electrolyte and a zinc electrode comprising a porous foam support material which carries the active zinc electrode material. 5 figs.

  9. Modeling Mercury in Proteins

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith, Jeremy C; Parks, Jerry M

    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 variousmore » 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.« less

  10. Mercury in stream ecosystems -- New studies initiated by the U.S. Geological Survey

    USGS Publications Warehouse

    Brigham, Mark E.; Krabbenhoft, David P.; Hamilton, Pixie A.

    2003-01-01

    Mercury can adversely affect humans and wildlife through consumption of contaminated fish, particularly by sensitive individuals, such as children and women of childbearing age. Mercury is currently the leading cause of impairment in the Nation’s estuaries and lakes and was cited in nearly 80 percent of fish-consumption advisories (2,242 of 2,838) reported by states in 2000. The geographic extent of mercury advisories covers more than 10 million acres of lakes and more than 400,000 stream miles—increases of about 7 and 48 percent, respectively, over advisories reported in 1998 (U.S. Environmental Protection Agency, 2002a).

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

    PubMed Central

    Buck, Kenton A.; Varian-Ramos, Claire W.; Cristol, Daniel A.; Swaddle, John P.

    2016-01-01

    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. PMID:27668745

  12. Relative toxicity of lead and five proposed substitute shot types to pen-reared mallards

    USGS Publications Warehouse

    Grandy, John W.; Locke, Louis N.; Bagley, George E.

    1968-01-01

    A 30-day toxicity test was made to determine the relative toxicity of lead, a tin-lead alloy, zinc, nickel, teflon-coated steel, and tin, all in shot form, to pen-reared mallard drakes. All of the 15 ducks dosed with lead died. Twenty-seven percent of 15 dosed with alloy, and 20 percent of 15 dosed with zinc also died. Ten of the remaining zinc-dosed ducks showed signs of distress, including losses of muscular control and body weight. There were no deaths among 15 ducks dosed with nickel, 15 dosed with teflon-coated steel, and 15 dosed with tin. Seventy-three percent of those dosed with nickel shot eliminated all shot before the end of the 30-day period. Acid-fast intranuclear inclusion bodies were present in the kidneys of mallards dosed with commercial lead shot, or with tin-lead alloy shot, but not in the kidneys of birds given nickel, tin, or teflon-coated steel shot. Atypical, pale, acid-fast bodies were found in kidneys of 1 of 15 birds dosed with zinc. An iron-containing pigment, which stained positive with the Prussian blue technique, was present in variable amounts in almost all livers. Zinc-dosed ducks that died or were killed while still showing signs of zinc intoxication had higher iron levels in the liver than ducks that had recovered from zinc intoxication.

  13. The Response of a 16S Ribosomal RNA Gene Fragment Amplified Community to Lead, Zinc, and Copper Pollution in a Shanghai Field Trial.

    PubMed

    Kou, Shumeng; Vincent, Gilles; Gonzalez, Emmanuel; Pitre, Frederic E; Labrecque, Michel; Brereton, Nicholas J B

    2018-01-01

    Industrial and agricultural activities have caused extensive metal contamination of land throughout China and across the globe. The pervasive nature of metal pollution can be harmful to human health and can potentially cause substantial negative impact to the biosphere. To investigate the impact of anthropogenic metal pollution found in high concentrations in industrial, agricultural, and urban environments, 16S ribosomal RNA gene amplicon sequencing was used to track change in the amplified microbial community after metal contamination in a large-scale field experiment in Shanghai. A total of 1,566 operational taxonomic units (OTUs) identified from 448,108 sequences gathered from 20 plots treated as controls or with lead, zinc, copper, or all three metals. Constrained Analysis of Principal Coordinates ordination did not separate control and lead treatment but could separate control/lead, zinc, copper, and three metal treatment. DESeq2 was applied to identify 93 significantly differentially abundant OTUs varying in 211 pairwise instances between the treatments. Differentially abundant OTUs representing genera or species belonging to the phyla Chloroflexi, Cyanobacteria, Firmicutes, Latescibacteria, and Planctomycetes were almost universally reduced in abundance due to zinc, copper, or three metal treatment; with three metal treatment abolishing the detection of some OTUs, such as Leptolyngbya , Desmonostoc muscorum , and Microcoleus steenstrupii . The greatest increases due to metal treatment were observed in Bacteroidetes, Actinobacteria, Chlamydiae, Nitrospirae, and Proteobacteria (α, β, δ, and γ); the most (relative) abundant being uncharacterized species within the genera Methylobacillus , Solirubrobacter , and Ohtaekwangia . Three metal treatment alone resulted in identification of 22 OTUs (genera or species) which were not detected in control soil, notably including Yonghaparkia alkaliphila , Pedobacter steynii , Pseudolabrys taiwanensis , Methylophilus

  14. The Response of a 16S Ribosomal RNA Gene Fragment Amplified Community to Lead, Zinc, and Copper Pollution in a Shanghai Field Trial

    PubMed Central

    Kou, Shumeng; Vincent, Gilles; Gonzalez, Emmanuel; Pitre, Frederic E.; Labrecque, Michel; Brereton, Nicholas J. B.

    2018-01-01

    Industrial and agricultural activities have caused extensive metal contamination of land throughout China and across the globe. The pervasive nature of metal pollution can be harmful to human health and can potentially cause substantial negative impact to the biosphere. To investigate the impact of anthropogenic metal pollution found in high concentrations in industrial, agricultural, and urban environments, 16S ribosomal RNA gene amplicon sequencing was used to track change in the amplified microbial community after metal contamination in a large-scale field experiment in Shanghai. A total of 1,566 operational taxonomic units (OTUs) identified from 448,108 sequences gathered from 20 plots treated as controls or with lead, zinc, copper, or all three metals. Constrained Analysis of Principal Coordinates ordination did not separate control and lead treatment but could separate control/lead, zinc, copper, and three metal treatment. DESeq2 was applied to identify 93 significantly differentially abundant OTUs varying in 211 pairwise instances between the treatments. Differentially abundant OTUs representing genera or species belonging to the phyla Chloroflexi, Cyanobacteria, Firmicutes, Latescibacteria, and Planctomycetes were almost universally reduced in abundance due to zinc, copper, or three metal treatment; with three metal treatment abolishing the detection of some OTUs, such as Leptolyngbya, Desmonostoc muscorum, and Microcoleus steenstrupii. The greatest increases due to metal treatment were observed in Bacteroidetes, Actinobacteria, Chlamydiae, Nitrospirae, and Proteobacteria (α, β, δ, and γ); the most (relative) abundant being uncharacterized species within the genera Methylobacillus, Solirubrobacter, and Ohtaekwangia. Three metal treatment alone resulted in identification of 22 OTUs (genera or species) which were not detected in control soil, notably including Yonghaparkia alkaliphila, Pedobacter steynii, Pseudolabrys taiwanensis, Methylophilus

  15. HUMAN SCALP HAIR: AN ENVIRONMENTAL EXPOSURE INDEX FOR TRACE ELEMENTS. II. SEVENTEEN TRACE ELEMENTS IN FOUR NEW JERSEY COMMUNITIES (1972)

    EPA Science Inventory

    Seventeen trace elements - arsenic (As), barium (Ba), boron (B), cadmium (Cd), chromium (Cr), copper (Cu), Iron (Fe), lead (Pb), lithium (Li), manganese (Mn), mercury (Hg), nickle (Ni), selenium (Se), silver (Ag), tin (Sn), vanadium (V), and zinc (Zn) - were measured in human sca...

  16. HUMAN SCALP HAIR: AN ENVIRONMENTAL EXPOSURE INDEX FOR TRACE ELEMENTS. III. SEVENTEEN TRACE ELEMENTS IN BIRMINGHAM, ALABAMA AND CHARLOTTE, NORTH CAROLINA (1972)

    EPA Science Inventory

    Seventeen trace elements - arsenic (As), barium (Ba), boron, (B), cadmium, (Cd), chromium (Cr), copper (Cu), Iron (Fe), lead (Pb), lithium (Li), manganese (Mn), mercury (Hg), nickel (Ni), selenium (Se), silver (Ag), tin (Sn), vanadium (V), and Zinc (Zn) - were measured in human s...

  17. Transport of dissolved trace elements in surface runoff and leachate from a coastal plain soil after poultry litter application

    USDA-ARS?s Scientific Manuscript database

    The application of poultry (Gallus gallus domesticus) litter to agricultural soils may exacerbate losses of trace elements in runoff water, an emerging concern to water quality. We evaluated trace elements (arsenic, cadmium, copper, lead, manganese, mercury, selenium and zinc) in surface runoff and ...

  18. Histopathology of mallards dosed with lead and selected substitute shot

    USGS Publications Warehouse

    Locke, L.N.; Irby, H.D.; Bagley, George E.

    1967-01-01

    The histopathological response of male game farm mallards fed lead, three types of plastic-coated lead, two lead-magnesium alloys, iron, copper, zinc-coated iron, and molybdenum-coated iron shot was studied. Mallards fed lead, plastic-coated lead, or lead-magnesium alloy shot developed a similar pathological response, including the formation of acid-fast intranuclear inclusion bodies in the kidneys. Birds fed iron or molybdenum-coated iron shot developed hemosiderosis of the liver. Two of four mallards fed zinc-coated iron shot also developed hemosiderosis of the liver. No lesions were found in mallards fed copper shot.

  19. Mercury, Lead, Cadmium, Cobalt, Arsenic and Selenium in the Blood of Semipalmated Sandpipers (Calidris pusilla) from Suriname, South America: Age-related Differences in Wintering Site and Comparisons with a Stopover Site in New Jersey, USA.

    PubMed

    Burger, Joanna; Mizrahi, David; Tsipoura, Nellie; Jeitner, Christian; Gochfeld, Michael

    2018-05-09

    It is essential to understand contaminant exposure and to compare levels of contaminants in organisms at different ages to determine if there is bioaccumulation, and to compare levels encountered in different geographical areas. In this paper, we report levels of mercury, lead, cadmium, cobalt, arsenic and selenium in the blood of semipalmated sandpipers ( Calidris pusilla ) wintering in Suriname as a function of age, and compare them to blood levels in northbound migrants at a stopover in Delaware Bay, New Jersey. We found (1) young birds had higher levels of cadmium, cobalt, and lead than adults (after second year birds); (2) there were no age-related differences for arsenic, mercury and selenium; (3) only four of the possible 16 inter-metal correlations were significant, at the 0.05 level; (4) the highest correlation was between cadmium and lead (Kendall tau = 0.37); and (5) the adult sandpipers had significantly higher levels of cadmium, mercury and selenium in Suriname than in New Jersey, while the New Jersey birds had significantly higher levels of arsenic. Suriname samples were obtained in April, after both age classes had spent the winter in Suriname, which suggests that sandpipers are accumulating higher levels of trace elements in Suriname than in Delaware Bay. The levels of selenium may be within a range of concern for adverse effects, but little is known about adverse effect levels of trace elements in the blood of wild birds.

  20. [Remediation Pb, Cd contaminated soil in lead-zinc mining areas by hydroxyapatite and potassium chloride composites].

    PubMed

    Wang, Li; Li, Yong-Hua; Ji, Yan-Fang; Yang, Lin-Sheng; Li, Hai-Rong; Zhang, Xiu-Wu; Yu, Jiang-Ping

    2011-07-01

    The composite agents containing potassium chloride (KCl) and Hydroxyapatite (HA) were used to remediate the lead and cadmium contaminated soil in Fenghuang lead-zinc mining-smelting areas, Hunan province. The objective of this study was to identify and evaluate the influence of Cl- to the fixing efficiency of Pb and Cd by HA. Two types of contaminated soil (HF-1, HF-2) were chosen and forty treatments were set by five different Hydroxyapatite (HA) dosages and four different Cl- dosages. The toxicity characteristic leaching procedure (TCLP) was used to evaluate the results. It showed that HA could efficiently fix the Pb and Cd from TCLP form. The maximum Pb-fixing efficiency and Cd-fixing efficiency of two types of soil were 83.3%, 97.27% and 35.96%, 57.82% when the HA: Pb: KCl molar ratio was 8: 1: 2. Compared to the fixing efficiency without KCl, KCl at the KCl: Pb molar ratio of 2 improved Pb-fixing efficiency and Cd-fixing efficiency by 6.26%, 0.33% and 7.74%, 0.83% respectively when the HA: Pb molar ratio was 8. Generally, Cl- can improve the Pb/Cd-fixing efficiency in heavy metal contaminated soil by Hydroxyapatite.

  1. Heavy metal contamination of sediments in the upper connecting channels of the Great Lakes

    USGS Publications Warehouse

    Nichols, S. Jerrine; Manny, Bruce A.; Schloesser, Donald W.; Edsall, Thomas A.

    1991-01-01

    In 1985, sampling at 250 stations throughout the St. Marys, St. Clair, and Detroit rivers and Lake St. Clair — the connecting channels of the upper Great Lakes — revealed widespread metal contamination of the sediments. Concentrations of cadmium, chromium, copper, lead, mercury, nickel, and zinc each exceeded U.S. Environmental Protection Agency sediment pollution guidelines at one or more stations throughout the study area. Sediments were polluted more frequently by copper, nickel, zinc, and lead than by cadmium, chromium, or mercury. Sediments with the highest concentrations of metals were found (in descending order) in the Detroit River, the St. Marys River, the St. Clair River, and Lake St. Clair. Although metal contamination of sediments was most common and sediment concentrations of metals were generally highest near industrial areas, substantial contamination of sediments by metals was present in sediment deposition areas up to 60 km from any known source of pollution.

  2. Mercury Quick Facts: Health Effects of Mercury Exposure

    MedlinePlus

    ... up in tiny cracks and spaces in your house. • • Mercury can vaporize (evaporate) into the air in your house. The vapor cannot be seen or smelled. • • Mercury ... up in tiny cracks and spaces in your house. • • Can vaporize (evaporate) into the air in your ...

  3. Mpo - the Bepicolombo Mercury Planetary Orbiter.

    NASA Astrophysics Data System (ADS)

    Benkhoff, J.

    2008-09-01

    proximity of the Sun Since and considering that the advance Mercury's perihelion was explained in terms of relativistic spacetime curvature. MPO Scientific Instruments BepiColombo Mercury Planetary Orbiter's and Mercury Magnetospheric Orbiter's instruments were selected in November 2004, by ESA and JAXA respectively. The MPO will carry a highly sophisticated suit of eleven scientific instruments, ten of which will be provided by Principal Investigators through national funding by ESA Member States and one from Russia: BepiColombo Laser Altimeter (BELA) will characterise the topography and surface morphology of Mercury. It will also provide a digital terrain model that, compared with the data from the MORE instrument, will allow to obtain information about the internal structure, the geology, the tectonics, and the age of the planet's surface. The objectives of the Italian Spring Accelerometer (ISA) are strongly connected with those of the MORE experiment. Together the experiments can give information on Mercury's interior structure as well as test Einstein's theory of the General Relativity. Mercury Magnetometer (MPO-MAG) will provide measurements that will lead to the detailed description of Mercury's planetary magnetic field and its source, to better understand the origin, evolution and current state of the planetary interior , as well as the interaction between Mercury's magnetosphere with the planet's itself and with the solar wind. Mercury Thermal Infrared Spectrometer (MERTIS) will provide detailed information about the mineralogical composition of Mercury's surface layer with a high spectral resolution, crucial for selecting the valid model for origin and evolution of the planet. Mercury Gamma ray and Neutron Spectrometer (MGNS) will determine the elemental compositions of the surface and subsurface of Mercury, and will determine the regional distribution of volatile depositions on the polar areas which are permanently shadowed from the Sun. Mercury Imaging X

  4. Anti-inflammatory effects of zinc in PMA-treated human gingival fibroblast cells

    PubMed Central

    Kim, Sangwoo; Jeon, Sangmi; Hui, Zheng; Kim, Young; Im, Yeonggwan; Lim, Wonbong; Kim, Changsu; Choi, Hongran; Kim, Okjoon

    2015-01-01

    Objectives: Abnormal cellular immune response has been considered to be responsible for oral lesions in recurrent aphthous stomatitis. Zinc has been known to be an essential nutrient metal that is necessary for a broad range of biological activities including antioxidant, immune mediator, and anti-inflammatory drugs in oral mucosal disease. The objective of this study was to investigate the effects of zinc in a phorbol-12-myristate-13-acetate (PMA)-treated inflammatory model on human gingival fibroblast cells (hGFs). Study Design: Cells were pre-treated with zinc chloride, followed by PMA in hGFs. The effects were assessed on cell viability, cyclooxygenease-1,2(COX-1/2) protein expression, PGE2 release, ROS production and cytokine release, Results: The effects were assessed on cell viability, COX1/2 protein expression, PGE2 release, ROS production, cytokine release. The results showed that, in the presence of PMA, zinc treatment leads to reduce the production of ROS, which results in decrease of COX-2 expression and PGE2 release. Conclusions: Thus, we suggest that zinc treatment leads to the mitigation of oral inflammation and may prove to be an alternative treatment for recurrent aphthous stomatitis. Key words:Zinc, inflammatory response, cytokines, phorbol-12-myristate-13-acetate, gingival fibroblasts cells. PMID:25662537

  5. Mercury Exposure and Heart Diseases

    PubMed Central

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

    2017-01-01

    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. PMID:28085104

  6. Mercury Exposure and Heart Diseases.

    PubMed

    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.

  7. X-ray absorption Studies of Zinc species in Centella asiatica

    NASA Astrophysics Data System (ADS)

    Dehipawala, Sunil; Cheung, Tak; Hogan, Clayton; Agoudavi, Yao; Dehipawala, Sumudu

    2013-03-01

    Zinc is a very important mineral present in a variety of vegetables. It is an essential element in cellular metabolism and several bodily functions. We used X-ray fluorescence, and X-ray Absorption near Edge structure(XANES) to study the amount of zinc present in several leafy vegetables as well as its chemical environment within the plant. Main absorption edge position of XANES is sensitive to the oxidation state of zinc and is useful when comparing the type of zinc present in different vegetables to the standard zinc present in supplements. Normalized main edge height is proportional to the amount of zinc present in the sample. Several leafy greens were used in this study, such as Spinacia oleracea, Basella alba, Brassica oleracea, Cardiospermum halicacabumand Centella asiatica. All of these plant leaves contained approximately the same amount of zinc in the leaf portion of the plant and a slightly lower amount in the stems, except Centella asiatica. Both leaves and stems of the plant Centella asiatica contained nearly two times the zinc compared to other plants. Further investigation of zinc's chemical environment within Centella asiatica could lead to a much more efficient dietary consumption of zinc. Use of the National Synchrotron Light Source, Brookhaven National Laboratory, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-98CH10886

  8. Influence of DNA-methylation on zinc homeostasis in myeloid cells: Regulation of zinc transporters and zinc binding proteins.

    PubMed

    Kessels, Jana Elena; Wessels, Inga; Haase, Hajo; Rink, Lothar; Uciechowski, Peter

    2016-09-01

    The distribution of intracellular zinc, predominantly regulated through zinc transporters and zinc binding proteins, is required to support an efficient immune response. Epigenetic mechanisms such as DNA methylation are involved in the expression of these genes. In demethylation experiments using 5-Aza-2'-deoxycytidine (AZA) increased intracellular (after 24 and 48h) and total cellular zinc levels (after 48h) were observed in the myeloid cell line HL-60. To uncover the mechanisms that cause the disturbed zinc homeostasis after DNA demethylation, the expression of human zinc transporters and zinc binding proteins were investigated. Real time PCR analyses of 14 ZIP (solute-linked carrier (SLC) SLC39A; Zrt/IRT-like protein), and 9 ZnT (SLC30A) zinc transporters revealed significantly enhanced mRNA expression of the zinc importer ZIP1 after AZA treatment. Because ZIP1 protein was also enhanced after AZA treatment, ZIP1 up-regulation might be the mediator of enhanced intracellular zinc levels. The mRNA expression of ZIP14 was decreased, whereas zinc exporter ZnT3 mRNA was also significantly increased; which might be a cellular reaction to compensate elevated zinc levels. An enhanced but not significant chromatin accessibility of ZIP1 promoter region I was detected by chromatin accessibility by real-time PCR (CHART) assays after demethylation. Additionally, DNA demethylation resulted in increased mRNA accumulation of zinc binding proteins metallothionein (MT) and S100A8/S100A9 after 48h. MT mRNA was significantly enhanced after 24h of AZA treatment also suggesting a reaction of the cell to restore zinc homeostasis. These data indicate that DNA methylation is an important epigenetic mechanism affecting zinc binding proteins and transporters, and, therefore, regulating zinc homeostasis in myeloid cells. Copyright © 2016 Elsevier GmbH. All rights reserved.

  9. Influence of Sulfide Nanoparticles on Dissolved Mercury and Zinc Quantification by Diffusive Gradient in Thin-Film Passive Samplers.

    PubMed

    Pham, Anh Le-Tuan; Johnson, Carol; Manley, Devon; Hsu-Kim, Heileen

    2015-11-03

    Diffusive gradient in thin-film (DGT) passive samplers are frequently used to monitor the concentrations of metals such as mercury and zinc in sediments and other aquatic environments. The application of these samplers generally presumes that they quantify only the dissolved fraction and not particle-bound metal species that are too large to migrate into the sampler. However, metals associated with very small nanoparticles (smaller than the pore size of DGT samplers) can be abundant in certain environments, yet the implications of these nanoparticles for DGT measurements are unclear. The objective of this study was to determine how the performance of the DGT sampler is affected by the presence of nanoparticulate species of Hg and Zn. DGT samplers were exposed to solutions containing known amounts of dissolved Hg(II) and nanoparticulate HgS (or dissolved Zn(II) and nanoparticulate ZnS). The amounts of Hg and Zn accumulated onto the DGT samplers were quantified over hours to days, and the rates of diffusion of the dissolved metal (i.e., the effective diffusion coefficient D) into the sampler's diffusion layer were calculated and compared for solutions containing varying concentrations of nanoparticles. The results suggested that the nanoparticles deposited on the surface of the samplers might have acted as sorbents, slowing the migration of the dissolved species into the samplers. The consequence was that the DGT sampler data underestimated the dissolved metal concentration in the solution. In addition, X-ray absorption spectroscopy was employed to determine the speciation of the Hg accumulated on the sampler binding layer, and the results indicated that HgS nanoparticles did not appear to directly contribute to the DGT measurement. Overall, our findings suggest that the deployment of DGT samplers in settings where nanoparticles are relevant (e.g., sediments) may result in DGT data that incorrectly estimated the dissolved metal concentrations. Models for metal uptake

  10. Mercury (Hg) and lead (Pb) in interior and exterior New Orleans house paint films.

    PubMed

    Mielke, Howard W; Gonzales, Chris

    2008-06-01

    Pre-1992, latex paint was formulated with mercury (Hg) as phenylmercuric acetate (PMA). Hg vaporizes reducing its content, and lead (Pb) is stable and remains unchanged. The objective of this study is to describe the content of Hg and Pb in existing paint coatings. Forty paint chip samples were collected from both interior and exterior surfaces of homes in metropolitan New Orleans and analyzed for Hg and Pb. The median Hg in exterior paints is 26.9 mg kg(-1) (0.8-214.0) compared with 7.1 mg kg(-1) (0.03-39.2) for interior paints. The median Pb content is 76603 mg kg(-1) (464-317151) and 416 mg kg(-1) (24-63313) respectively, for exterior and interior paints. The Spearman correlation coefficients for Hg and Pb are -0.312 (P=0.13) and -0.471 (P=0.07) respectively, in exterior and interior samples. Hg and Pb vary independently with each other in paint films. Median Hg in exterior paints is four times larger than for interior paints. Median Pb in exterior paints is 184 times larger than interior paints. The Pb and Hg content in exterior and interior paint chips are significantly different (Mann-Whitney Rank Sum Test, P0.001 and P=0.006, respectively). Only 1 of the 25 exterior paints contained less than the current 5000 mg kg(-1) US standard for Pb, the criteria for exemption from the power-sanding restrictions of the New Orleans Lead Ordinance. Prior to banning PMA in paint, Hg poisonings presented as acrodynia were reported for children living in homes freshly painted with latex paint. Because of the affinity of Hg and Pb for sulfur-containing amino acid proteins, their presence in paint coatings poses an increased hazard when released as dust.

  11. Assessment of mobility and bioavailability of mercury compounds in sewage sludge and composts.

    PubMed

    Janowska, Beata; Szymański, Kazimierz; Sidełko, Robert; Siebielska, Izabela; Walendzik, Bartosz

    2017-07-01

    Content of heavy metals, including mercury, determines the method of management and disposal of sewage sludge. Excessive concentration of mercury in composts used as organic fertilizer may lead to accumulation of this element in soil and plant material. Fractionation of mercury in sewage sludge and composts provides a better understanding of the extent of mobility and bioavailability of the different mercury species and helps in more informed decision making on the application of sludge for agricultural purposes. The experimental setup comprises the composing process of the sewage sludge containing 13.1mgkg -1 of the total mercury, performed in static reactors with forced aeration. In order to evaluate the bioavailability of mercury, its fractionation was performed in sewage sludge and composts during the process. An analytical procedure based on four-stage sequential extraction was applied to determine the mercury content in the ion exchange (water soluble and exchangeable Hg), base soluble (Hg bound to humic and fulvic acid), acid soluble (Hg bound to Fe/Mn oxides and carbonates) and oxidizable (Hg bound to organic matter and sulphide) fractions. The results showed that from 50.09% to 64.55% of the total mercury was strongly bound to organo-sulphur and inorganic sulphide; that during composting, increase of concentrations of mercury compounds strongly bound with organic matter and sulphides; and that mercury content in the base soluble and oxidizable fractions was strongly correlated with concentration of dissolved organic carbon in those fractions. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. 40 CFR 437.46 - Pretreatment standards for existing sources (PSES).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....409 0.120 Titanium 0.0947 0.0618 Vanadium 0.218 0.0662 Zinc 2.87 0.641 Organic Parameters Bis(2... 1.45 Silver 0.120 0.0351 Tin 0.409 0.120 Titanium 0.0947 0.0618 Vanadium 0.218 0.0662 Zinc 2.87 0... Lead 1.32 0.283 Mercury 0.00234 0.000739 Nickel 3.95 1.45 Silver 0.120 0.0351 Tin 0.409 0.120 Titanium...

  13. Mercury contamination of aquatic ecosystems

    USGS Publications Warehouse

    Krabbenhoft, David P.; Rickert, David A.

    1995-01-01

    Mercury has been well known as an environmental pollutant for several decades. As early as the 1950's it was established that emissions of mercury to the environment could have serious effects on human health. These early studies demonstrated that fish and other wildlife from various ecosystems commonly attain mercury levels of toxicological concern when directly affected by mercury-containing emissions from human-related activities. Human health concerns arise when fish and wildlife from these ecosystems are consumed by humans. During the past decade, a new trend has emerged with regard to mercury pollution. Investigations initiated in the late 1980's in the northern-tier states of the U.S., Canada, and Nordic countries found that fish, mainly from nutrient-poor lakes and often in very remote areas, commonly have high levels of mercury. More recent fish sampling surveys in other regions of the U.S. have shown widespread mercury contamination in streams, wet-lands, reservoirs, and lakes. To date, 33 states have issued fish consumption advisories because of mercury contamination. These continental to global scale occurrences of mercury contamination cannot be linked to individual emissions of mercury, but instead are due to widespread air pollution. When scientists measure mercury levels in air and surface water, however, the observed levels are extraordinarily low. In fact, scientists have to take extreme precautions to avoid direct contact with water samples or sample containers, to avert sample contamination (Fig 3). Herein lies an apparent discrepancy: Why do fish from some remote areas have elevated mercury concentrations, when contamination levels in the environment are so low?

  14. Method of capturing or trapping zinc using zinc getter materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hunyadi Murph, Simona E.; Korinko, Paul S.

    2017-07-11

    A method of trapping or capturing zinc is disclosed. In particular, the method comprises a step of contacting a zinc vapor with a zinc getter material. The zinc getter material comprises nanoparticles and a metal substrate.

  15. Experimental Constraints on the Chemical Differentiation of Mercurys Mantle

    NASA Technical Reports Server (NTRS)

    Boujibar, A.; Righter, K.; Pando, K.; Danielson, L.

    2015-01-01

    Mercury is known as being the most reduced terrestrial planet with the highest core/mantle ratio. Results from MESSENGER spacecraft have shown that its surface is FeO-poor (2-4 wt%) and S-rich (up to 6-7 wt%), which confirms the reducing nature of its silicate mantle. In addition several features suggest important melting stages of the Mercurian mantle: widespread volcanic deposits on its surface, a high crustal thickness (approximately 10% of the planet's volume) and chemical compositions of its surface suggesting several stages of differentiation and remelting processes. Therefore it is likely that igneous processes like magma ocean crystallization and continuous melting have induced chemical and mineralogical heterogeneities in the Mercurian mantle. The extent and nature of compositional variations produced by partial melting remains poorly constrained for the particular compositions of Mercury (very reducing conditions, low FeO-contents and high sulfur-contents). Melting experiments with bulk Mercury-analogue compositions are scarce and with poorly con-trolled starting compositions. Therefore additional experimental data are needed to better understand the differentiation processes that lead to the observed chemical compositions of Mercury's surface.

  16. The Zinc Concentration in the Diet and the Length of the Feeding Period Affect the Methylation Status of the ZIP4 Zinc Transporter Gene in Piglets

    PubMed Central

    Karweina, Diana; Kreuzer-Redmer, Susanne; Müller, Uwe; Franken, Tobias; Pieper, Robert; Baron, Udo; Olek, Sven; Zentek, Jürgen; Brockmann, Gudrun A.

    2015-01-01

    High doses of zinc oxide are commonly used in weaned pig diets to improve performance and health. Recent reports show that this may also lead to an imbalanced zinc homeostasis in the animal. For a better understanding of the regulatory mechanisms of different zinc intakes, we performed a feeding experiment to assess potential epigenetic regulation of the ZIP4 gene expression via DNA methylation in the small intestine of piglets. Fifty-four piglets were fed diets with 57 (LZn), 164 (NZn) or 2,425 (HZn) mg Zn/kg feed for one or four weeks. The ZIP4 expression data provided significant evidence for counter-regulation of zinc absorption with higher dietary zinc concentrations. The CpG +735 in the second exon had a 56% higher methylation in the HZn group compared to the others after one week of feeding (8.0·10-4 < p < 0.035); the methylation of this CpG was strongly negatively associated with the expression of the long ZIP4 transcripts (p < 0.007). In the LZn and NZn diets, the expression of the long ZIP4 transcripts were lower after four vs. one week of feeding (2.9·10-4 < p < 0.017). The strongest switch leading to high DNA methylation in nearly all analysed regions was dependent on feeding duration or age in all diet groups (3.7·10-10 < p < 0.099). The data suggest that DNA methylation serves as a fine-tuning mechanism of ZIP4 gene regulation to maintain zinc homeostasis. Methylation of the ZIP4 gene may play a minor role in the response to very high dietary zinc concentration, but may affect binding of alternate zinc-responsive transcription factors. PMID:26599865

  17. Effects of environmental lead contamination on cattle in a lead/zinc mining area: changes in cattle immune systems on exposure to lead in vivo and in vitro.

    PubMed

    Ikenaka, Yoshinori; Nakayama, Shouta M M; Muroya, Taro; Yabe, John; Konnai, Satoru; Darwish, Wageh Sobhy; Muzandu, Kaampwe; Choongo, Kennedy; Mainda, Geoffrey; Teraoka, Hiroki; Umemura, Takashi; Ishizuka, Mayumi

    2012-10-01

    The Republic of Zambia is rich in mineral resources, such as zinc (Zn) and lead (Pb), and mining is a key industry in Zambia. A previous study of Pb pollution in Kabwe, one of the main mining areas, found that soil was contaminated with high levels of toxic metals over a substantial area. In the present study, the authors focus on toxic metal pollution in cattle, one of the most important domestic animals in Zambia. Blood samples from cattle in Kabwe and a control area (Lusaka) were tested for toxic metal content. They also measured mRNA expression of metal-responsive proteins and cytokines in white blood cells using real-time reverse transcriptase polymerase chain reaction. In the present in vitro study, The authors cultured peripheral blood mononuclear cells (PBMCs) from cattle, exposing them to Pb acetate for 24 h and analyzing mRNA expression of metal-responsive proteins and selected cytokines. Lead concentrations in cattle blood from Kabwe were significantly greater than those from Lusaka, as were the mRNA expressions of metallothionein-2 (MT-2), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-1β (IL-1β), IL-6, and inducible nitric oxide synthase (iNOS). The present in vitro study demonstrated that Pb exposure led to an increase in the expressions of MT-2, TNF-α, IL-1β, and iNOS, similar to those found in vivo. These results indicate the possibility of immune system modulations in cattle from the Kabwe area. Copyright © 2012 SETAC.

  18. Bioaccumulation of mercury in benthic communities of a river ecosystem affected by mercury mining.

    PubMed

    Zizek, Suzana; Horvat, Milena; Gibicar, Darija; Fajon, Vesna; Toman, Mihael J

    2007-05-15

    The presence of mercury in the river Idrijca (Slovenia) is mainly due to 500 years of mercury mining in this region. In order to understand the cycling of mercury in the Idrijca ecosystem it is crucial to investigate the role of biota. This study is part of an ongoing investigation of mercury biogeochemistry in the river Idrijca, focusing on the accumulation and speciation of mercury in the lower levels of the food chain, namely filamentous algae, periphyton and macroinvertebrates. Mercury analysis and speciation in the biota and in water were performed during the spring, summer and autumn seasons at four locations on the river, representing different degrees of mercury contamination. Total (THg) and methyl mercury (MeHg) were measured. The results showed that the highest THg concentrations in biota correlate well with THg levels in sediments and water. The level of MeHg is spatially and seasonally variable, showing higher values at the most contaminated sites during the summer and autumn periods. The percentage of Hg as MeHg increases with the trophic level from water (0.1-0.8%), algae (0.5-1.3%), periphyton (1.6-8.8%) to macroinvertebrates (0.1-100%), which indicates active transformation, accumulation and magnification of mercury in the benthic organism of this heavily contaminated torrential river.

  19. Au 2PbP 2, Au 2TlP 2, and Au 2HgP 2: Ternary Gold Polyphosphides with Lead, Thallium, and Mercury in the Oxidation State Zero

    NASA Astrophysics Data System (ADS)

    Eschen, Marcus; Jeitschko, Wolfgang

    2002-05-01

    The polyphosphide Au2PbP2 was prepared by reaction of the elemental components using liquid lead as a reaction medium. Well-developed crystals were obtained after dissolving the matrix in hydrochloric acid. Their crystal structure was determined from four-circle X-ray diffractometer data: Cmcm, a=323.6(1) pm, b=1137.1(2) pm, c=1121.8(1) pm, Z=4, R=0.023 for 478 structure factors and 20 variable parameters. The structure contains zigzag chains of phosphorus atoms with a typical single-bond distance of 219.4(2) pm. The two different kinds of gold atoms are both in linear phosphorus coordination with typical single-bond distances of 232.6(2) and 234.2(2) pm, and the lead atoms have only metal neighbors (7 Au and 2 Pb). Accordingly, chemical bonding of the compound may be expressed by the formula (Au+1)2Pb±0(P-1)2. The corresponding thallium and mercury polyphosphides Au2TlP2 (a=324.1(1) pm, b=1136.1(1) pm, c=1122.1(1) pm) and Au2HgP2 (a=322.1(1) pm, b=1131.4(2) pm, c=1122.6(1) pm) were found to be almost isotypic with Au2PbP2. Their crystal structures were refined from single-crystal X-ray data to R=0.036 (682 F values, 25 variables) and R=0.026 (539 F values, 35 variables), respectively. The structure of these compounds may also be described as consisting of a three-dimensional network of condensed 8- and 10-membered Au2P6 and Au4P6 rings forming parallel channels, which are filled by the lead, thallium, and mercury atoms. The lead atoms are well localized in these channels, while the thallium and even more the mercury atoms occupy additional positions within these channels. Freshly prepared samples of Au2HgP2 show reproducibly slightly different axial ratios and larger cell volumes (ΔV=0.5%) than those after exposure of the samples to air for several days.

  20. Geochemical and mineralogical characterization of the abandoned Valzinco (lead-zinc) and Mitchell (gold) mine sites prior to reclamation, Spotsylvania County, Virginia

    USGS Publications Warehouse

    Hammarstrom, Jane M.; Johnson, Adam N.; Seal, Robert R.; Meier, Allen L.; Briggs, Paul L.; Piatak, Nadine M.

    2006-01-01

    The Virginia gold-pyrite belt, part of the central Virginia volcanic-plutonic belt, hosts numerous abandoned metal mines. The belt extends from about 50 km south of Washington, D.C., for approximately 175 km to the southwest into central Virginia. The rocks that comprise the belt include metamorphosed volcanic and clastic (noncarbonate) sedimentary rocks that were originally deposited during the Ordovician). Deposits that were mined can be classified into three broad categories: 1. volcanic-associated massive sulfide deposits, 2. low-sulfide quartz-gold vein deposits, 3. gold placer deposits, which result from weathering of the vein deposits The massive sulfide deposits were historically mined for iron and pyrite (sulfur), zinc, lead, and copper but also yielded byproduct gold and silver. The most intensely mineralized and mined section of the belt is southwest of Fredericksburg, in the Mineral district of Louisa and Spotsylvania counties. The Valzinco Piatak lead-zinc mine and the Mitchell gold prospect are abandoned sites in Spotsylvania County. As a result of environmental impacts associated with historic mining, both sites were prioritized for reclamation under the Virginia Orphaned Land Program administered by the Virginia Department of Mines, Minerals, and Energy (VDMME). This report summarizes geochemical data for all solid sample media, along with mineralogical data, and results of weathering experiments on Valzinco tailings and field experiments on sediment accumulation in Knights Branch. These data provide a framework for evaluating water-rock interactionsand geoenvironmental signatures of long-abandoned mines developed in massive sulfide deposits and low-sulfide gold-quartz vein deposits in the humid temperate ecosystem domain in the eastern United States.