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Sample records for total mercury tothg

  1. Total and methyl mercury concentrations and fluxes from small boreal forest catchments in Finland

    International Nuclear Information System (INIS)

    Porvari, Petri; Verta, Matti

    2003-01-01

    Peatlands have higher methyl mercury output than uplands. - Total mercury (TotHg) and methyl mercury (MeHg) concentrations were studied in runoff from eight small (0.02-1.3 km 2 ) boreal forest catchments (mineral soil and peatland) during 1990-1995. Runoff waters were extremely humic (TOC 7-70 mg l -1 ). TotHg concentrations varied between 0.84 and 24 ng l -1 and MeHg between 0.03 and 3.8 ng l -1 . TotHg fluxes from catchments ranged from 0.92 to 1.8 g km -2 a -1 , and MeHg fluxes from 0.03 to 0.33 g km -2 a -1 . TotHg concentrations and output fluxes measured in runoff water from small forest catchments in Finland were comparable with those measured in other boreal regions. By contrast, MeHg concentrations were generally higher. Estimates for MeHg output fluxes in this study were comparable at sites with forests and wetlands in Sweden and North America, but clearly higher than those measured at upland or agricultural sites in other studies. Peatland catchments released more MeHg than pure mineral soil or mineral soil catchments with minor area of peatland

  2. Biomagnification of mercury in selected species from an Arctic marine food web in Svalbard

    International Nuclear Information System (INIS)

    Jaeger, Iris; Hop, Haakon; Gabrielsen, Geir W.

    2009-01-01

    Concentrations and biomagnification of total mercury (TotHg) and methyl mercury (MeHg) were studied in selected species from the pelagic food web in Kongsfjorden, Svalbard. Twelve species of zooplankton, fish and seabirds, were sampled representing a gradient of trophic positions in the Svalbard marine food web. TotHg and MeHg were analysed in liver, muscle and/or whole specimens. The present study is the first to provide MeHg levels in seabirds from the Svalbard area. The relative MeHg levels decreased with increasing levels of TotHg in seabird tissues. Stable isotopes of nitrogen (δ 15 N) were used to determine the trophic levels and the rate of biomagnification of mercury in the food web. A linear relationship between mercury levels and trophic position was found for all seabird species combined and their trophic level, but there was no relationship within species. Biomagnification factors were all > 1 for both TotHg and MeHg, indicating biomagnification from prey to predator. TotHg levels in the different seabirds were similar to levels detected in the Kongsfjorden area in the 1990s.

  3. Mercury concentrations in water resources potentially impacted by coal-fired power stations and artisanal gold mining in Mpumalanga, South Africa.

    Science.gov (United States)

    Williams, Chavon R; Leaner, Joy J; Nel, Jaco M; Somerset, Vernon S

    2010-09-01

    Total mercury (TotHg) and methylmercury (MeHg) concentrations were determined in various environmental compartments collected from water resources of three Water Management Areas (WMAs) - viz. Olifants, Upper Vaal and Inkomati WMAs, potentially impacted by major anthropogenic mercury (Hg) sources (i.e coal-fired power stations and artisanal gold mining activities). Aqueous TotHg concentrations were found to be elevated above the global average (5.0 ng/L) in 38% of all aqueous samples, while aqueous MeHg concentrations ranged from below the detection limit (0.02 ng/L) to 2.73 +/- 0.10 ng/L. Total Hg concentrations in surface sediment (0-4 cm) ranged from 0.75 +/- 0.01 to 358.23 +/- 76.83 ng/g wet weight (ww). Methylmercury accounted for, on average, 24% of TotHg concentrations in sediment. Methylmercury concentrations were not correlated with TotHg concentrations or organic content in sediment. The concentration of MeHg in invertebrates and fish were highest in the Inkomati WMA and, furthermore, measured just below the US EPA guideline for MeHg in fish.

  4. Wood ash or dolomite treatment of catchment areas - effects of mercury in runoff water

    Energy Technology Data Exchange (ETDEWEB)

    Parkman, H; Munthe, J [Swedish Environmental Research Inst., Stockholm (Sweden)

    1996-11-01

    A future increased use of biomass as a source of energy, and the planned restoration of mineral nutrient balance in the forest soils by returning the wood ashes, has led to concern for new environmental disturbances. The objectives of the present study were to investigate if the outflow of total mercury (TotHg) and methyl mercury (MeHg) from catchment areas treated with granulated wood ash (1988, 2.2 tons/ha, `ashed area`) or dolomite (1985, 5 tons/ha, `limed area`) differed from the outflow from an untreated (reference) area, and if variations in Hg outflow were correlated with changes in the outflow of organic substances or pH. The study areas are situated in Vaermland, Sweden. Samples of run-off water were taken weekly or monthly (depending on water-flow) during on year (1993-94). The outflow of MeHg, TotHg as well as H+ and dissolved organic material (DOC) was lower from the limed area compared to the other two areas, which did not differ significantly. There was a strong covariation between concentrations of DOC and MeHg and a weaker relation between DOC and TotHg in the run-off waters. MeHg also covaried with temperature while TotHg covaried with pH and water-supply. No difference was found when comparing Hg-data from the limed area before, directly after and eight years after the liming event. 13 refs, 12 figs, 1 tab

  5. Total Mercury content of skin toning creams

    African Journals Online (AJOL)

    Administrator

    2008-04-01

    Apr 1, 2008 ... used it for cosmetics (Silberberg, 1995). Mercury- ... Cosmetic preparations containing mercury com- pounds are .... mercury determination by a modified version of an open .... level mercury exposure, which could lead to a.

  6. AAS determination of total mercury content in environmental samples

    International Nuclear Information System (INIS)

    Moskalova, M.; Zemberyova, M.

    1997-01-01

    Two methods for determination of total mercury content in environmental samples soils, and sediments, were compared. Dissolution procedure of soils, sediments, and biological material under elevated pressure followed by determination of mercury by cold vapour atomic absorption spectrometry using a MHS-1 system and direct total mercury determination without any chemical pretreatment from soil samples using a Trace Mercury Analyzer TMA-254 were compared. TMA-254 was also applied for the determination of mercury in various further standard reference materials. Good agreement with certified values of environmental reference materials was obtained. (authors)

  7. Total Mercury content of skin toning creams

    African Journals Online (AJOL)

    Administrator

    2008-04-01

    Apr 1, 2008 ... Kwame Nkrumah University of Science & Technology,. Kumasi, Ghana. ABSTRACT. The use of mercury containing skin toning creams is becoming ..... Country of Origin. Colour. Aleo Whitening Milk. 0.013. China. White.

  8. Total mercury concentration in common fish species of Lake Victoria ...

    African Journals Online (AJOL)

    Total mercury (THg) concentration was analysed in muscles of common fish species of Lake Victoria in the eastern and southern parts of the lake using cold vapour Atomic Absorption Spectrophotometric technique. Mercury concentration in all fish species was generally lower than the WHO maximum allowable ...

  9. Total mercury of selected fish species from Laguna de Bay

    International Nuclear Information System (INIS)

    Relon, Milagros Lontoc

    1996-01-01

    Dalag Ophicephalus striatus Block, kanduli Arius thalassinus Ruppell, bia Amblygobius phalaena Cuvier et Valenciennes and tilapia Tilapia nilotica Linnnaeus collected from Laguna de Bay between Taguig and Binangonan area in August 1989 to July 1990 were analyzed for total mercury by atomic absorption spectrometry. The highest metal concentration in soft muscle tissue was observed in Dalag followed by kanduli, less in bia and least in tilapia with mean values of 0.021, 0.020, 0.013, and 0.008 ug/g, respectively. Analysis using two-way ANOVA showed a significant difference in the mean total mercury in ug/g in the difference fish samples, among the different months and the interaction between these two variables. Mean total mercury of the four fish samples were significantly higher in April than in October. The results show that the levels of total mercury in the fish samples are below the World Health Organization maximum tolerable consumption of mercury in food of 300 ug or 0.03 mg of total mercury per week. (author)

  10. Vertical Distribution of Total Mercury and Mercury Methylation in a Landfill Site in Japan

    Directory of Open Access Journals (Sweden)

    Jing Yang

    2018-06-01

    Full Text Available Mercury is a neurotoxin, with certain organic forms of the element being particularly harmful to humans. The Minamata Convention was adopted to reduce the intentional use and emission of mercury. Because mercury is an element, it cannot be decomposed. Mercury-containing products and mercury used for various processes will eventually enter the waste stream, and landfill sites will become a mercury sink. While landfill sites can be a source of mercury pollution, the behavior of mercury in solid waste within a landfill site is still not fully understood. The purpose of this study was to determine the depth profile of mercury, the levels of methyl mercury (MeHg, and the factors controlling methylation in an old landfill site that received waste for over 30 years. Three sampling cores were selected, and boring sampling was conducted to a maximum depth of 18 m, which reached the bottom layer of the landfill. Total mercury (THg and MeHg were measured in the samples to determine the characteristics of mercury at different depths. Bacterial species were identified by 16S rRNA amplification and sequencing, because the methylation process is promoted by a series of genes. It was found that the THg concentration was 19–975 ng/g, with a geometric mean of 298 ng/g, which was slightly less than the 400 ng/g concentration recorded 30 years previously. In some samples, MeHg accounted for up to 15–20% of THg, which is far greater than the general level in soils and sediments, although the source of MeHg was unclear. The genetic data indicated that hgcA was present mostly in the upper and lower layers of the three cores, merA was almost as much as hgcA, while the level of merB was hundreds of times less than those of the other two genes. A significant correlation was found between THg and MeHg, as well as between MeHg and MeHg/THg. In addition, a negative correlation was found between THg and merA. The coexistence of the three genes indicated that both

  11. Determination of total mercury in nuts at ultratrace level

    International Nuclear Information System (INIS)

    Silva, Maria José da; Paim, Ana Paula S.; Pimentel, Maria Fernanda; Cervera, M. Luisa; Guardia, Miguel de la

    2014-01-01

    Highlights: • Direct analysis of Hg in nuts has been improved by a previous fat removal. • Comparison of cold vapour atomic fluorescence and direct analysis of Hg in nuts. • Mercury content in tree nuts was determined. - Abstract: Total mercury, at μg kg −1 level, was determined in different types of nuts (cashew nut, Brazil nuts, almond, pistachio, peanut, walnut) using a direct mercury analyser after previous sample defatting and by cold vapour atomic fluorescence spectrometry. There is not enough sensitivity in the second approach to determine Hg in previously digested samples due to the strong matrix effect. Mercury levels in 25 edible nut samples from Brazil and Spain were found in the range from 0.6 to 2.7 μg kg −1 by using the pyrolysis of sample after the extraction of the nut fat. The accuracy of the proposed method was confirmed by analysing certified reference materials of Coal Fly Ash-NIST SRM 1633b, Fucus-IAEA 140 and three unpolished Rice Flour NIES-10. The observed results were in good agreement with the certified values. The recoveries of different amounts of mercury added to nut samples ranged from 94 to 101%. RSD values corresponding to three measurements varied between 2.0 and 14% and the limit of detection and quantification of the method were 0.08 and 0.3 μg kg −1 , respectively

  12. Determination of total mercury in nuts at ultratrace level

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Maria José da, E-mail: maryquimica@yahoo.com.br [Departamento de Química – Universidade Federal Rural de Pernambuco, Rue Dom Manoel de Medeiros s/n. Dois irmãos, 52171-900 Recife, PE (Brazil); Paim, Ana Paula S. [Departamento de Química Fundamental – Universidade Federal de Pernambuco, Cidade Universitária, 50740-550 Recife, PE (Brazil); Pimentel, Maria Fernanda [Departamento de Engenharia Química – Universidade Federal de Pernambuco, Recife, PE (Brazil); Cervera, M. Luisa; Guardia, Miguel de la [Department of Analytical Chemistry, Research Building, University of Valencia, 50th Dr. Moliner Street, E-46100 Burjassot, Valencia (Spain)

    2014-08-01

    Highlights: • Direct analysis of Hg in nuts has been improved by a previous fat removal. • Comparison of cold vapour atomic fluorescence and direct analysis of Hg in nuts. • Mercury content in tree nuts was determined. - Abstract: Total mercury, at μg kg{sup −1} level, was determined in different types of nuts (cashew nut, Brazil nuts, almond, pistachio, peanut, walnut) using a direct mercury analyser after previous sample defatting and by cold vapour atomic fluorescence spectrometry. There is not enough sensitivity in the second approach to determine Hg in previously digested samples due to the strong matrix effect. Mercury levels in 25 edible nut samples from Brazil and Spain were found in the range from 0.6 to 2.7 μg kg{sup −1} by using the pyrolysis of sample after the extraction of the nut fat. The accuracy of the proposed method was confirmed by analysing certified reference materials of Coal Fly Ash-NIST SRM 1633b, Fucus-IAEA 140 and three unpolished Rice Flour NIES-10. The observed results were in good agreement with the certified values. The recoveries of different amounts of mercury added to nut samples ranged from 94 to 101%. RSD values corresponding to three measurements varied between 2.0 and 14% and the limit of detection and quantification of the method were 0.08 and 0.3 μg kg{sup −1}, respectively.

  13. Total mercury, methyl mercury, and carbon in fresh and burned plants and soil in Northwestern Ontario

    International Nuclear Information System (INIS)

    Mailman, M.; Bodaly, R.A.

    2005-01-01

    Terrestrial plants and soil contain substantial amounts of organic carbon (C) and mercury. Flooding terrestrial areas stimulates microbial methyl mercury (MeHg) production and fish obtain elevated MeHg concentrations. Our purpose was to determine the loss of C, total mercury (THg), and MeHg from boreal plants and soil after burning to assess the potential of burning before flooding to lower MeHg. Fresh plants contained 4 to 52 ng g -1 dry weight (dw) of THg and 0.1 to 1.3 ng g -1 dw of MeHg. Upland soils contained 162±132 ng g -1 dw of THg and 0.6±0.6 ng g -1 dw of MeHg. Complete burning caused plants to lose 96, 98, 97, and 94% of the mass, C, THg, and MeHg, respectively. Upland soil lost 27, 95, 79, and 82% of the mass, C, THg, and MeHg, respectively. Our results demonstrated that a substantial loss of C, THg, and MeHg was caused by burning. - Burning terrestrial vegetation and soil causes substantial losses of organic carbon, total mercury, and methyl mercury

  14. Total mercury, methyl mercury, and carbon in fresh and burned plants and soil in Northwestern Ontario

    Energy Technology Data Exchange (ETDEWEB)

    Mailman, M. [Department of Zoology, University of Manitoba, Winnipeg, Man. R3T 2N2 (Canada); Freshwater Institute, 501 University Crescent, Winnipeg, Man. R3T 2N6 (Canada)]. E-mail: mailmanma@dfo-mpo.gc.ca; Bodaly, R.A. [Department of Zoology, University of Manitoba, Winnipeg, Man. R3T 2N2 (Canada); Freshwater Institute, 501 University Crescent, Winnipeg, Man. R3T 2N6 (Canada)

    2005-11-15

    Terrestrial plants and soil contain substantial amounts of organic carbon (C) and mercury. Flooding terrestrial areas stimulates microbial methyl mercury (MeHg) production and fish obtain elevated MeHg concentrations. Our purpose was to determine the loss of C, total mercury (THg), and MeHg from boreal plants and soil after burning to assess the potential of burning before flooding to lower MeHg. Fresh plants contained 4 to 52 ng g{sup -1} dry weight (dw) of THg and 0.1 to 1.3 ng g{sup -1} dw of MeHg. Upland soils contained 162{+-}132 ng g{sup -1} dw of THg and 0.6{+-}0.6 ng g{sup -1} dw of MeHg. Complete burning caused plants to lose 96, 98, 97, and 94% of the mass, C, THg, and MeHg, respectively. Upland soil lost 27, 95, 79, and 82% of the mass, C, THg, and MeHg, respectively. Our results demonstrated that a substantial loss of C, THg, and MeHg was caused by burning. - Burning terrestrial vegetation and soil causes substantial losses of organic carbon, total mercury, and methyl mercury.

  15. Total mercury, organic mercury and selenium in liver and kidney of a South American coastal dolphin

    International Nuclear Information System (INIS)

    Seixas, Tercia G.; Kehrig, Helena do A.; Costa, Monica; Fillmann, Gilberto; Di Beneditto, Ana Paula M.; Secchi, Eduardo R.; Souza, Cristina M.M.; Malm, Olaf; Moreira, Isabel

    2008-01-01

    Selenium and total and organic mercury were determined in the liver and kidney of franciscana dolphin (Pontoporia blainvillei) incidentally caught in fishing nets along two Brazilian coastal areas (southeast and south). Regional differences in the concentrations of these contaminants were observed in P. blainvillei. Liver showed the highest organic and total mercury. In general, samples of individuals collected at the southern of Brazil had the highest concentrations of selenium and total and organic mercury. No significant gender differences were observed. Growth stage influenced the accumulation of these contaminants in both organs, and hepatic concentrations increased with the body length, according to the sampling area. Molar mercury and selenium concentrations in liver were significantly correlated, with a Se:Hg ratio close to 4. The among-site differences we found may be related to differences in preferred prey, bioavailability in the marine environment, environmental conditions, or these individuals may belong to distinct populations. - This study presents some useful data on the bioaccumulation of Hg, organic Hg and Se, and their inter-element relationships in a Brazilian small cetacean

  16. Total mercury, organic mercury and selenium in liver and kidney of a South American coastal dolphin

    Energy Technology Data Exchange (ETDEWEB)

    Seixas, Tercia G. [Departamento de Quimica, PUC-Rio, 22453-900 Rio de Janeiro, RJ (Brazil); Laboratorio de Radioisotopos Eduardo Penna Franca, IBCCF-UFRJ, 21949-900 Rio de Janeiro, RJ (Brazil)], E-mail: tercia@rdc.puc-rio.br; Kehrig, Helena do A. [Laboratorio de Radioisotopos Eduardo Penna Franca, IBCCF-UFRJ, 21949-900 Rio de Janeiro, RJ (Brazil); Costa, Monica [Departamento de Oceanografia, CTG-UFPE, 50740-550 Recife, PE (Brazil); Fillmann, Gilberto [Departamento de Oceanografia, FURG, C.P. 474, 96201-900 Rio Grande, RS (Brazil); Di Beneditto, Ana Paula M. [Laboratorio de Ciencias Ambientais, CBB-UENF, 28013-602 Campos dos Goytacazes, RJ (Brazil); Secchi, Eduardo R. [Departamento de Oceanografia, FURG, C.P. 474, 96201-900 Rio Grande, RS (Brazil); Laboratorio de Tartarugas e Mamiferos Marinhos, Departamento de Oceanografia e Museu Oceanografico ' Prof. E.C. Rios' , FURG, 96201-900 Rio Grande, RS (Brazil); Souza, Cristina M.M. [Laboratorio de Ciencias Ambientais, CBB-UENF, 28013-602 Campos dos Goytacazes, RJ (Brazil); Malm, Olaf [Laboratorio de Radioisotopos Eduardo Penna Franca, IBCCF-UFRJ, 21949-900 Rio de Janeiro, RJ (Brazil); Moreira, Isabel [Departamento de Quimica, PUC-Rio, 22453-900 Rio de Janeiro, RJ (Brazil)

    2008-07-15

    Selenium and total and organic mercury were determined in the liver and kidney of franciscana dolphin (Pontoporia blainvillei) incidentally caught in fishing nets along two Brazilian coastal areas (southeast and south). Regional differences in the concentrations of these contaminants were observed in P. blainvillei. Liver showed the highest organic and total mercury. In general, samples of individuals collected at the southern of Brazil had the highest concentrations of selenium and total and organic mercury. No significant gender differences were observed. Growth stage influenced the accumulation of these contaminants in both organs, and hepatic concentrations increased with the body length, according to the sampling area. Molar mercury and selenium concentrations in liver were significantly correlated, with a Se:Hg ratio close to 4. The among-site differences we found may be related to differences in preferred prey, bioavailability in the marine environment, environmental conditions, or these individuals may belong to distinct populations. - This study presents some useful data on the bioaccumulation of Hg, organic Hg and Se, and their inter-element relationships in a Brazilian small cetacean.

  17. Total dietary intake of mercury in the Canary Islands, Spain.

    Science.gov (United States)

    Rubio, C; Gutiérrez, A; Burgos, A; Hardisson, A

    2008-08-01

    Estimating the risk associated with dietary intake of heavy metals by consumers is a vital and integral part of regulatory processes. The assessment of exposure to mercury shown in this paper has been performed by means of a study on the whole diet. Total mercury (Hg) levels were determined by cold vapour atomic absorption spectrometry (AAS) in 420 samples of regularly consumed food and drink. The total Hg concentrations measured in the different groups of food ranged from non-detectable to 119 microg kg(-1) w/w. The fish group had the highest concentrations of total Hg. All groups of food with regulated Hg content showed levels that were lower than the legally set values. The food consumption data used in the analysis were taken from the latest nutritional survey made in the Canary Islands, Spain. The estimated total Hg intake of local population (5.7 microg/person day(-1)) did not exceed the provisional tolerable weekly intake (PTWI) limit of 0.3 mg week(-1) of total mercury (43 microg/person day(-1)) fixed by the Joint Food and Agricultural Organization/World Health Organization (FAO/WHO) Expert Committee on Food Additives. Fishery products contributed 96% of the total Hg intake. The mean Hg intake for each island in this archipelago, formed by seven, has also been calculated. Fuerteventura, Lanzarote and El Hierro are the islands with the highest level of Hg intake (7.0, 7,0 and 6.1 microg/person day(-1), respectively). La Palma Island, due to its low fish consumption, had the lowest level of Hg intake (4.5 microg/person day(-1)), followed by La Gomera (5.4 microg/person day(-1)), Tenerife (5.5 microg/person day(-1)) and Gran Canaria (5.6 microg/person day(-1)). A comparison has been made of the results obtained in this study with those found for other national and international communities.

  18. Factors influencing concentrations of dissolved gaseous mercury (DGM) and total mercury (TM) in an artificial reservoir

    International Nuclear Information System (INIS)

    Ahn, Myung-Chan; Kim, Bomchul; Holsen, Thomas M.; Yi, Seung-Muk; Han, Young-Ji

    2010-01-01

    The effects of various factors including turbidity, pH, DOC, temperature, and solar radiation on the concentrations of total mercury (TM) and dissolved gaseous mercury (DGM) were investigated in an artificial reservoir in Korea. Episodic total mercury accumulation events occurred during the rainy season as turbidity increased, indicating that the TM concentration was not controlled by direct atmospheric deposition. The DGM concentration in surface water ranged from 3.6 to 160 pg/L, having a maximum in summer and minimum in winter. While in most previous studies DGM was controlled primarily by a photo-reduction process, DGM concentrations tracked the amount of solar radiation only in winter when the water temperature was fairly low in this study. During the other seasons microbial transformation seemed to play an important role in reducing Hg(II) to Hg(0). DGM increased as dissolved organic carbon (DOC) concentration increased (p-value < 0.01) while it increased with a decrease of pH (p-value < 0.01). - Long-term in-situ monitoring of TM and DGM concentrations with various factors was executed in a large artificial reservoir in this study.

  19. Improved estimates of filtered total mercury loadings and total mercury concentrations of solids from potential sources to Sinclair Inlet, Kitsap County, Washington

    Science.gov (United States)

    Paulson, Anthony J.; Conn, Kathleen E.; DeWild, John F.

    2013-01-01

    Previous investigations examined sources and sinks of mercury to Sinclair Inlet based on historic and new data. This included an evaluation of mercury concentrations from various sources and mercury loadings from industrial discharges and groundwater flowing from the Bremerton naval complex to Sinclair Inlet. This report provides new data from four potential sources of mercury to Sinclair Inlet: (1) filtered and particulate total mercury concentrations of creek water during the wet season, (2) filtered and particulate total mercury releases from the Navy steam plant following changes in the water softening process and discharge operations, (3) release of mercury from soils to groundwater in two landfill areas at the Bremerton naval complex, and (4) total mercury concentrations of solids in dry dock sumps that were not affected by bias from sequential sampling. The previous estimate of the loading of filtered total mercury from Sinclair Inlet creeks was based solely on dry season samples. Concentrations of filtered total mercury in creek samples collected during wet weather were significantly higher than dry weather concentrations, which increased the estimated loading of filtered total mercury from creek basins from 27.1 to 78.1 grams per year. Changes in the concentrations and loading of filtered and particulate total mercury in the effluent of the steam plant were investigated after the water softening process was changed from ion-exchange to reverse osmosis and the discharge of stack blow-down wash began to be diverted to the municipal water-treatment plant. These changes reduced the concentrations of filtered and particulate total mercury from the steam plant of the Bremerton naval complex, which resulted in reduced loadings of filtered total mercury from 5.9 to 0.15 grams per year. Previous investigations identified three fill areas on the Bremerton naval complex, of which the western fill area is thought to be the largest source of mercury on the base

  20. EFFECTS OF COMMONLY USED COOKING PRACTICES ON TOTAL MERCURY CONCENTRATION IN FISH AND THEIR IMPACT ON EXPOSURE ASSESSMENTS

    Science.gov (United States)

    The effects of cooking practices commonly used by Native Americans on total mercury concentrations in fish were investigated. A preparation factor relating mercury concentrations in fish as prepared for consumption to mercury concentration data as measured in typical environmenta...

  1. Form of Dietary Methylmercury does not Affect Total Mercury Accumulation in the Tissues of Zebra Finch.

    Science.gov (United States)

    Varian-Ramos, Claire W; Whitney, Margaret; Rice, Gary W; Cristol, Daniel A

    2017-07-01

    Exposure to mercury in humans, other mammals, and birds is primarily dietary, with mercury in the methylated form and bound to cysteine in the tissues of prey items. Yet dosing studies are generally carried out using methylmercury chloride. Here we tested whether the accumulation of total mercury in zebra finch blood, egg, muscle, liver, kidney or brain differed depending on whether dietary mercury was complexed with chloride or cysteine. We found no effect of form of mercury on tissue accumulation. Some previous studies have found lower accumulation of mercury in tissues of animals fed complexed mercury. Much remains to be understood about what happens to ingested mercury once it enters the intestines, but our results suggest that dietary studies using methylmercury chloride in birds will produce similar tissue accumulation levels to those using methylmercury cysteine.

  2. Description and advantages of the new and dry total mercury CEM HM 14000 trust

    Energy Technology Data Exchange (ETDEWEB)

    Kasajanow, J.

    2002-07-01

    A series of 24 overheads/slides outline the presentation giving details of the design and operation of the continuous emission monitor - the Total Mercury CEM HM 1400TR produced by the Durag Group. The monitor is suitable for measuring mercury emitted from power plants. The principle components of the monitor, the thermocatalytic reactor, and the dual beam UV detector are described, along with the calibration. Also the Portable Total Mercury CEM and the Total Mercury CEM 1500 for liquids are pictured. The presentation was made by Verewa, part of the Durag Group.

  3. Mercury

    International Nuclear Information System (INIS)

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

    1988-01-01

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

  4. Total mercury, methylmercury and selenium in mercury polluted areas in the province Guizhou, China.

    Science.gov (United States)

    Horvat, Milena; Nolde, Natasa; Fajon, Vesna; Jereb, Vesna; Logar, Martina; Lojen, Sonja; Jacimovic, Radojko; Falnoga, Ingrid; Liya, Qu; Faganeli, Jadran; Drobne, Damjana

    2003-03-20

    The province of Guizhou in Southwestern China is currently one of the world's most important mercury production areas. Emissions of mercury from the province to the global atmosphere have been estimated to be approximately 12% of the world total anthropogenic emissions. The main objective of this study was to assess the level of contamination with Hg in two geographical areas of Guizhou province. Mercury pollution in the areas concerned originates from mercury mining and ore processing in the area of Wanshan, while in the area of Quingzhen mercury pollution originates from the chemical industry discharging Hg through wastewaters and emissions to the atmosphere due to coal burning for electricity production. The results of this study confirmed high contamination with Hg in soil, sediments and rice in the Hg mining area in Wanshan. High levels of Hg in soil and rice were also found in the vicinity of the chemical plant in Quingzhen. The concentrations of Hg decreased with distance from the main sources of pollution considerably. The general conclusion is that Hg contamination in Wanshan is geographically more widespread, due to deposition and scavenging of Hg from contaminated air and deposition on land. In Quingzhen Hg contamination of soil is very high close to the chemical plant but the levels reach background concentrations at a distance of several km. Even though the major source of Hg in both areas is inorganic Hg, it was observed that active transformation of inorganic Hg to organic Hg species (MeHg) takes place in water, sediments and soils. The concentration of Hg in rice grains can reach up to 569 microg/kg of total Hg of which 145 microg/kg was in MeHg form. The percentage of Hg as MeHg varied from 5 to 83%. The concentrations of selenium can reach up to 16 mg/kg in soil and up to 1 mg/g in rice. A correlation exists between the concentration of Se in soil and rice, indicating that a portion of Se is bioavailable to plants. No correlation between Hg and Se

  5. Determination of total mercury and methylmercury in human head hair by radiochemical methods of analysis

    International Nuclear Information System (INIS)

    Vasconcellos, M.B.A.; Saiki, M.; Paletti, G.; Baruzzi, R.G.; Rodrigues, D.A.; Cuten, J.

    1995-01-01

    Total mercury has been determined by instrumental neutron activation analysis in the hair of several Indian tribes living in the Xingu Park, located in the Amazonic region of Brazil. Methylmercury and total mercury have been determined in selected samples using cold vapour atomic absorption spectroscopy, at the Nuclear Chemistry Department, Jozef Stefan Institute, Ljubliana, Slovenia. Mercury levels were found to be much higher in the Indian hair samples as compared to the samples from the control population. The arithmetic and geometric means for total mercury in the Indian hair samples ranged from 10 to 20 ppm, compared to values of about 1 ppm for the means of the control group. The results obtained for methylmercury have shown that the majority of the mercury is present in the hair of the Indians as the organic form. The Indian study populations living in the Xingu Park can thus be considered as being at risk with regards to contamination by mercury. With the aim of applying neutron activation analysis for the determination of methylmercury in hair, experiments were done at the IEA-R1 nuclear research reactor irradiating cysteine- and also thioacetamide- impregnated filter papers, on which a methylmercury solution was pipetted. The results obtained have shown that all the mercury was lost from the cysteine-impregnated paper and about 90 % of the mercury remained on the paper impregnated with thioacetamide. (author)

  6. Baseline monitoring of mercury levels in environmental matrices in the Limpopo Province

    CSIR Research Space (South Africa)

    Walters, Chavon

    2017-02-01

    Full Text Available and HP 3396 Integrator. 32 Total Hg (TotHg) concentrations in surface sediment and freshwater fish samples were determined following 33 USEPA protocols (Method 7473; USEPA 2007). The TotHg in solid samples, i.e. sediment and freeze-dried 34 fish, were... and anonymous reviewers for giving us many constructive 13 comments that significantly improved the paper. 14 6. References 15 Andersson, I., Parkman, H. & Jernelov, A. (1990). The role of sediments as sink or source for environmental 16 contaminants: A case...

  7. Total and methyl mercury, moisture, and porosity in Lake Michigan surficial sediment

    Data.gov (United States)

    U.S. Environmental Protection Agency — Total and methyl mercury, moisture content (%), and porosity were measured in Lake Michigan sediment by the U.S. Environmental Protection Agency/Office of Research...

  8. DETERMINATION OF TOTAL MERCURY IN FISH TISSUES USING PYROLYSIS ATOMIC ABSORPTION SPECTROMETRY WITH GOLD AMALGAMATION

    Science.gov (United States)

    A simple and rapid procedure for measuring total mercury in fish tissues is evaluated and compared with conventional techniques. Using an automated instrument incorporating combustion, preconcentration by amalgamation with gold, and atomic absorption spectrometry (AAS), mill...

  9. Real-time analysis of total, elemental, and total speciated mercury

    International Nuclear Information System (INIS)

    Schlager, R.J.; Wilson, K.G.; Sappey, A.D.

    1995-01-01

    ADA Technologies, Inc., is developing a continuous emissions monitoring system that measures the concentrations of mercury in flue gas. Mercury is emitted as an air pollutant from a number of industrial processes. The largest contributors of these emissions are coal and oil combustion, municipal waste combustion, medical waste combustion, and the thermal treatment of hazardous materials. It is difficult, time consuming, and expensive to measure mercury emissions using current testing methods. Part of the difficulty lies in the fact that mercury is emitted from sources in several different forms, such as elemental mercury and mercuric chloride. The ADA analyzer measures these emissions in real time, thus providing a number of advantages over existing test methods: (1) it will provide a real-time measure of emission rates, (2) it will assure facility operators, regulators, and the public that emissions control systems are working at peak efficiency, and (3) it will provide information as to the nature of the emitted mercury (elemental mercury or speciated compounds). This update presents an overview of the CEM and describes features of key components of the monitoring system--the mercury detector, a mercury species converter, and the analyzer calibration system

  10. Real-time analysis of total, elemental, and total speciated mercury

    Energy Technology Data Exchange (ETDEWEB)

    Schlager, R.J.; Wilson, K.G.; Sappey, A.D. [ADA Technologies, Inc., Englewood, CO (United States)

    1995-11-01

    ADA Technologies, Inc., is developing a continuous emissions monitoring system that measures the concentrations of mercury in flue gas. Mercury is emitted as an air pollutant from a number of industrial processes. The largest contributors of these emissions are coal and oil combustion, municipal waste combustion, medical waste combustion, and the thermal treatment of hazardous materials. It is difficult, time consuming, and expensive to measure mercury emissions using current testing methods. Part of the difficulty lies in the fact that mercury is emitted from sources in several different forms, such as elemental mercury and mercuric chloride. The ADA analyzer measures these emissions in real time, thus providing a number of advantages over existing test methods: (1) it will provide a real-time measure of emission rates, (2) it will assure facility operators, regulators, and the public that emissions control systems are working at peak efficiency, and (3) it will provide information as to the nature of the emitted mercury (elemental mercury or speciated compounds). This update presents an overview of the CEM and describes features of key components of the monitoring system--the mercury detector, a mercury species converter, and the analyzer calibration system.

  11. Determination and assessment of total mercury levels in local, frozen and canned fish in Lebanon.

    Science.gov (United States)

    Obeid, Pierre J; El-Khoury, Bilal; Burger, Joanne; Aouad, Samer; Younis, Mira; Aoun, Amal; El-Nakat, John Hanna

    2011-01-01

    Fish is an important constituent of the Lebanese diet. However, very little attention in our area is given to bring awareness regarding the effect of the toxicity of mercury (Hg) mainly through fish consumption. This study aimed to report analytical data on total mercury levels in several fish species for the first time in thirty years and to also made individuals aware of the presence and danger from exposure to mercury through fish consumption. Fish samples were selected from local Lebanese markets and fisheries and included 94 samples of which were fresh, frozen, processed, and canned fish. All values were reported as microgram of mercury per gram of fish based on wet weight. The level of mercury ranged from 0.0190 to 0.5700 microg/g in fresh samples, 0.0059 to 0.0665 microg/g in frozen samples, and 0.0305 to 0.1190 microg/g in canned samples. The data clearly showed that higher levels of mercury were detected in local fresh fish as opposed to other types thus placing consumers at higher risk from mercury exposure. Moreover, the data revealed that Mallifa (yellowstripe barracuda/Sphyraena chrysotaenia), Sargous (white seabream/Diplodus sargus), Ghobbos (bogue/Boops boops), and shrimp (Penaeus sp.) were among the types containing the highest amounts of mercury. On the other hand, processed fish such as fish fillet, fish burger, small shrimp and crab are found to contain lower levels of mercury and are associated with lower exposure risks to mercury. Lebanese population should therefore, be aware to consume limited amounts of fresh local fish to minimize exposure to mercury.

  12. Total mercury and mercury species in birds and fish in an aquatic ecosystem in the Czech Republic

    International Nuclear Information System (INIS)

    Houserova, Pavlina; Kuban, Vlastimil; Kracmar, Stanislav; Sitko, Jilji

    2007-01-01

    Total mercury and mercury species (methylmercury-MeHg, inorganic mercury - Hg 2+ ) were determined in the aquatic ecosystem Zahlinice (Czech Republic). Four tissues (muscle, intestines, liver and kidney) of three bird species - cormorant, great crested grebe and Eurasian buzzard, muscle tissues of common carp, grass carp, northern pike, goldfish, common tench, perch and rudd, aquatic plants (reed mace and common reed), sediments and water were analysed. Relative contents of MeHg (of total Hg) were in the range from 71% to 94% and from 15% up to 62% in the muscle and intestines and in liver, respectively, for all birds. Statistically significant differences were found between contents of MeHg in liver tissues of young and adult cormorant populations (F 4.6 = 56.71, P -5 ). Relative contents of MeHg in muscle tissues of fishes were in the range from 65.1% to 87.9% of total Hg. - The distribution of the mercury species among the organs of the individual birds is discussed

  13. Total mercury and mercury species in birds and fish in an aquatic ecosystem in the Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Houserova, Pavlina [Department of Chemistry and Biochemistry, Mendel University of Agriculture and Forestry, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Kuban, Vlastimil [Department of Chemistry and Biochemistry, Mendel University of Agriculture and Forestry, Zemedelska 1, CZ-613 00 Brno (Czech Republic)]. E-mail: kuban@mendelu.cz; Kracmar, Stanislav [Department of Animal Nutrition, Mendel University of Agriculture and Forestry, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Sitko, Jilji [Commenius Museum, Moravian Ornithological Station, Horni nam. 1, Prerov CZ-751 52 (Czech Republic)

    2007-01-15

    Total mercury and mercury species (methylmercury-MeHg, inorganic mercury - Hg{sup 2+}) were determined in the aquatic ecosystem Zahlinice (Czech Republic). Four tissues (muscle, intestines, liver and kidney) of three bird species - cormorant, great crested grebe and Eurasian buzzard, muscle tissues of common carp, grass carp, northern pike, goldfish, common tench, perch and rudd, aquatic plants (reed mace and common reed), sediments and water were analysed. Relative contents of MeHg (of total Hg) were in the range from 71% to 94% and from 15% up to 62% in the muscle and intestines and in liver, respectively, for all birds. Statistically significant differences were found between contents of MeHg in liver tissues of young and adult cormorant populations (F {sub 4.6} = 56.71, P < 10{sup -5}). Relative contents of MeHg in muscle tissues of fishes were in the range from 65.1% to 87.9% of total Hg. - The distribution of the mercury species among the organs of the individual birds is discussed.

  14. Streamwater fluxes of total mercury and methylmercury into and out of Lake Champlain

    International Nuclear Information System (INIS)

    Shanley, James B.; Chalmers, Ann T.

    2012-01-01

    From 2000 to 2004, we sampled for total mercury (THg) and methylmercury (MeHg) in inlet streams to Lake Champlain, targeting high flow periods to capture increases in THg and MeHg concentrations with increasing flow. We used these data to model stream THg and MeHg fluxes for Water Years 2001 through 2009. In this mountainous forested basin with a high watershed-to-lake area ratio of 18, fluvial export from the terrestrial watershed was the dominant source of Hg to the lake. Unfiltered THg and MeHg fluxes were dominated by the particulate fraction; about 40% of stream THg was in the filtered ( −2 yr −1 , or about 13% of atmospheric Hg wet and dry deposition to the basin. THg export from the lake represented only about 3% of atmospheric Hg input to the basin. - Highlights: ► We monitored total mercury and methylmercury in major tributaries to Lake Champlain. ► Mercury and methylmercury export was primarily as particulates during high flow. ► Only 13% of atmospheric total mercury input reached the lake via streams. ► Only 3% of atmospheric total mercury input reached the lake outlet. - Eighty-seven percent of total mercury deposition to the Lake Champlain basin is retained in the terrestrial basin; stream export of total and methylmercury to the lake is primarily in the particulate phase.

  15. Mercury in foods from the first French total diet study on infants and toddlers.

    Science.gov (United States)

    Guérin, Thierry; Chekri, Rachida; Chafey, Claude; Testu, Christian; Hulin, Marion; Noël, Laurent

    2018-01-15

    A very sensitive method using a direct mercury analyser was developed and validated according to the accuracy profile procedure to determine mercury levels in foods mainly consumed by infants and toddlers. Total mercury was not detected (LOD of 0.30µg.kg -1 fresh weight) in 92.4% of the 291 food samples analysed or at relatively low concentrations, lesser than or equal to LB/UB 0.5/1.0µg.kg -1 in all samples, except in fish samples (mean LB/UB 25µg.kg -1 with a maximum of 53µg.kg -1 ). Levels of total mercury in these foods were in all cases within permitted Regulatory limits of 500 or 1000µg.kg -1 in fishery products and muscle meat of fish. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Mercury

    Science.gov (United States)

    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 ...

  17. Total mercury and methyl-mercury contents and accumulation in polar microbial mats.

    Science.gov (United States)

    Camacho, Antonio; Rochera, Carlos; Hennebelle, Raphaëlle; Ferrari, Christophe; Quesada, Antonio

    2015-03-15

    Although polar regions are considered isolated and pristine areas, the organisms that inhabit these zones are exposed to global pollution. Heavy metals, such as mercury, are global pollutants and can reach almost any location on Earth. Mercury may come from natural, volcanic or geological sources, or result from anthropogenic sources, in particular industrial or mining activities. In this study, we have investigated one of the most prominent biological non-marine communities in both polar regions, microbial mats, in terms of their Hg and methyl-mercury (MeHg) concentrations and accumulation capacities. The main hypotheses posed argued on the importance of different factors, and to test them, we have measured Hg concentrations in microbial mats that were collected from 6 locations in different ecological situations. For this purpose, the direct anthropogenic impacts, volcanic influences, proximity to the seashore, latitudinal gradients and C contents were investigated. Our results show that, other than the direct anthropogenic influence, none of the other hypotheses alone satisfactorily explains the Hg content in microbial mats. In contrast, the MeHg contents were noticeably different between the investigated locations, with a higher proportion of MeHg on the McMurdo Ice Shelf (Antarctica) and a lower proportion on Ward Hunt Island (High Arctic). Furthermore, our results from in situ experiments indicated that the microbial mats from South Shetland Islands could quickly accumulate (48 h) Hg when Hg dissolved salts were supplied. Over short-term periods, these mats do not transform Hg into MeHg under field conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Total mercury levels in commercial fish species from Italian fishery and aquaculture.

    Science.gov (United States)

    Di Lena, Gabriella; Casini, Irene; Caproni, Roberto; Fusari, Andrea; Orban, Elena

    2017-06-01

    Total mercury levels were measured in 42 commercial fish species caught off the Central Adriatic and Tyrrhenian coasts of Italy and in 6 aquaculture species. The study on wild fish covered species differing in living habitat and trophic level. The study on farmed fish covered marine and freshwater species from intensive and extensive aquaculture and their feed. Mercury levels were analysed by thermal decomposition-amalgamation-atomic absorption spectrophotometry. Total mercury concentrations in the muscle of wild fish showed a high variability among species (0.025-2.20 mg kg -1 wet weight). The lowest levels were detected in low trophic-level demersal and pelagic-neritic fish and in young individuals of high trophic-level species. Levels exceeding the European Commission limits were found in large-size specimens of high trophic-level pelagic and demersal species. Fish from intensive farming showed low levels of total mercury (0.008-0.251 mg kg -1 ). Fish from extensive rearing showed variable contamination levels, depending on the area of provenience. An estimation of the human intake of mercury associated to the consumption of the studied fish and its comparison with the tolerable weekly intake is provided.

  19. Mercury

    NARCIS (Netherlands)

    de Vries, Irma

    2017-01-01

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

  20. Levels of total mercury in predatory fish sold in Canada in 2005

    OpenAIRE

    Dabeka, R.W.; McKenzie, A.D.; Forsyth, D.S.

    2011-01-01

    Total mercury was analysed in 188 samples of predatory fish purchased at the retail level in Canada in 2005. The average concentrations (ng g−1, range) were: sea bass 329 (38–1367), red snapper 148 (36–431), orange roughy 543 (279–974), fresh water trout 55 (20–430), grouper 360 (8–1060), black cod 284 (71–651), Arctic char 37 (28–54), king fish 440 (42–923), tilefish 601 (79–1164) and marlin 854 (125–2346). The Canadian standard for maximum total mercury allowed in the edible portions of fis...

  1. The dynamics of mercury near Idrija mercury mine, Slovenia: Horizontal and vertical distributions of total, methyl, and ethyl mercury concentrations in soils.

    Science.gov (United States)

    Tomiyasu, Takashi; Kodamatani, Hitoshi; Imura, Ryusuke; Matsuyama, Akito; Miyamoto, Junko; Akagi, Hirokatsu; Kocman, David; Kotnik, Jože; Fajon, Vesna; Horvat, Milena

    2017-10-01

    The distributions of the total mercury (T-Hg), methylmercury (MeHg), and ethylmercury (EtHg) concentrations in soil and their relationship to chemical composition of the soil and total organic carbon content (TOC, %) were investigated. Core samples were collected from hill slope on the right and left riverbanks of the Idrija River. Former smelting plant is located on the right bank. The T-Hg average in each of the core samples ranged from 0.25 to 1650 mg kg -1 . The vertical T-Hg variations in the samples from the left bank showed no significant change with depth. Conversely, the T-Hg varied with depth, with the surface, or layers several centimeters from the surface, tending to show the highest values in the samples from the right bank. Since the right and left bank soils have different chemical compositions, different pathways of mercury delivery into soils were suggested. The MeHg and EtHg concentrations ranged from n.d. (not detected) to 444 μg kg -1 and n.d. to 17.4 μg kg -1 , respectively. The vertical variations of MeHg and EtHg were similar to those of TOC, except for the near-surface layers containing TOC greater than 20%. These results suggest that the decomposition of organic matter is closely related to organic mercury formation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Total mercury in water, sediments, and animals along the Indian Coast

    Digital Repository Service at National Institute of Oceanography (India)

    Sanzgiri, S.; Mesquita, A.; Kureishy, T.W.

    Total mercury (Hg) in water, sediments and animals along the coast of India is estimated. Water samples were collected on board of R.V. Gaveshani.The zooplankton samples were collected by Indian Ocean Standard Net and Heron Tranter nets of 500 mesh...

  3. Determination of total mercury in aluminium industrial zones and soil contaminated with red mud.

    Science.gov (United States)

    Rasulov, Oqil; Zacharová, Andrea; Schwarz, Marián

    2017-08-01

    This study investigated total mercury contents in areas impacted by aluminium plants in Tajikistan and Slovakia and in one area flooded with red mud in Hungary. We present the first determination of total mercury contents in the near-top soil (0-10 and 10-20 cm) in Tajikistan and the first comparative investigation of Tajikistan-Slovakia-Hungary. The Tajik Aluminium Company (TALCO) is one of the leading producers of primary aluminium in Central Asia. In the past 30 years, the plant has been producing large volumes of industrial waste, resulting in negative impacts on soil, groundwater and air quality of the surrounding region. Mercury concentrations were significant in Slovakia and Hungary, 6 years after the flooding. In studied areas in Slovakia and Hungary, concentrations of total mercury exceeded the threshold limit value (TLV = 0.5 mg Hg kg -1 ). However, in Tajikistan, values were below the TLV (0.006-0.074 mg kg -1 ) and did not significantly vary between depths. Total Hg in Slovakia ranged from 0.057 to 0.668 mg kg -1 and in Hungary from 0.029 to 1.275 mg kg -1 . However, in the plots near to the red mud reservoir and the flooded area, Hg concentrations were higher in the upper layers than in the lower ones.

  4. Total mercury in water and sediment from Honda Bay area in Palawan

    International Nuclear Information System (INIS)

    Kapauan, A.F.; Kapauan, P.A.; Tan, E.O.; Verceluz, F.P.

    1980-01-01

    This project is intended to pinpoint the sources of mercury contamination from the Honda Bay area in Palawan. Sampling sites were pinpointed which water and sediment samples were to be taken and kept in virgin polyethylene liter bottles. Analytical procedures were applied. The results of the analysis for total mercury content vary cosiderably from ml, less than 0.003 ng/9 to high of 0.419 ng/g with a considerable number of the sample going above the 0.100 ng/g level. Sediment samples also gave similar results, from a low of 0.004 ng/g to value higher than 2 ng/g round the jetty. It can be concluded, therefore, that the area surveyed is contaminated with mercury but not severely so. (author)

  5. Robust microwave-assisted extraction protocol for determination of total mercury and methylmercury in fish tissues

    Energy Technology Data Exchange (ETDEWEB)

    Reyes, L. Hinojosa; Rahman, G.M. Mizanur [Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282 (United States); Kingston, H.M. Skip [Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282 (United States)], E-mail: kingston@duq.edu

    2009-01-12

    A rapid and efficient closed vessel microwave-assisted extraction (MAE) method based on acidic leaching was developed and optimized for the extraction of total mercury (Hg), inorganic mercury (Hg{sup 2+}) and methylmercury (CH{sub 3}Hg{sup +}) from fish tissues. The quantitative extraction of total Hg and mercury species from biological samples was achieved by using 5 mol L{sup -1} HCl and 0.25 mol L{sup -1} NaCl during 10 min at 60 deg. C. Total Hg content was determined using inductively coupled plasma mass spectrometry (ICP-MS). Mercury species were measured by liquid chromatography hyphenated with inductively coupled plasma mass spectrometry (LC-ICP-MS). The method was validated using biological certified reference materials ERM-CE464, DOLT-3, and NIST SRM-1946. The analytical results were in good agreement with the certified reference values of total Hg and CH{sub 3}Hg{sup +} at a 95% confidence level. Further, accuracy validation using speciated isotope-dilution mass spectrometry (SIDMS, as described in the EPA Method 6800) was carried out. SIDMS was also applied to study and correct for unwanted species transformation reactions during and/or after sample preparation steps. For the studied reference materials, no statistically significant transformation between mercury species was observed during the extraction and determination procedures. The proposed method was successfully applied to fish tissues with good agreement between SIDMS results and external calibration (EC) results. Interspecies transformations in fish tissues were slightly higher than certified reference materials due to differences in matrix composition. Depending on the type of fish tissue, up to 10.24% of Hg{sup 2+} was methylated and up to 1.75% of CH{sub 3}Hg{sup +} was demethylated to Hg{sup 2+}.

  6. Species differences in total mercury concentration in gulls from the Gulf of Gdansk (Southern Baltic).

    Science.gov (United States)

    Szumiło-Pilarska, Emilia; Grajewska, Agnieszka; Falkowska, Lucyna; Hajdrych, Julia; Meissner, Włodzimierz; Frączek, Tomasz; Bełdowska, Magdalena; Bzoma, Szymon

    2016-01-01

    Aquatic birds occupy a high position in the trophic pyramid of the Baltic Sea. This means that they accumulate the greatest amount of harmful substances, including mercury, in their bodies. This element penetrates into their systems mainly via the alimentary canal. The amount of mercury absorbed from food depends on how badly the environment is polluted with this metal. The aim of this study was to discover the concentrations of total mercury (HgT) in the contour feathers, muscles, brain, lungs, liver, kidneys, heart and blood of four gull species Herring Gull (Larus argentatus), Common Gull (Larus canus), Black-headed Gull (Larus ridibundus) and Great Black-backed Gull (Larus marinus) and organic mercury (Hgorg) in the liver and brain of Herring Gull. The most important characteristic of the results obtained for the studied gulls was the statistically significant differences between the four species, probably resulting from their different diets-confirmed by stable-isotopes analysis (δ(15)N and δ(13)C). A logarithmic dependence was found between HgT in the blood and HgT in the brain of the Herring Gull. The authors suggest that among gulls burdened with the greatest mercury load, it is possible that the brain is protected by higher Hg accumulation in the muscles. The percentage share of Hgorg in the brain and liver of the Herring Gull depended on the concentration of HgT in these tissues and was always higher in the brain. In none of the cases, did the mercury levels assayed in the internal gulls' tissues exceed values associated with adverse health effects. Copyright © 2015 Elsevier GmbH. All rights reserved.

  7. Measuring total mercury due to small-scale gold mining activities to determine community vulnerability in Cihonje, Central Java, Indonesia.

    Science.gov (United States)

    Sari, Mega M; Inoue, Takanobu; Matsumoto, Yoshitaka; Yokota, Kuriko

    2016-01-01

    This research is comparative study of gold mining and non-gold mining areas, using four community vulnerability indicators. Vulnerability indicators are exposure degree, contamination rate, chronic, and acute toxicity. Each indicator used different samples, such as wastewater from gold mining process, river water from Tajum river, human hair samples, and health questionnaire. This research used cold vapor atomic absorption spectrometry to determine total mercury concentration. The result showed that concentration of total mercury was 2,420 times than the maximum content of mercury permitted in wastewater based on the Indonesian regulation. Moreover, the mercury concentration in river water reached 685 ng/l, exceeding the quality threshold standards of the World Health Organization (WHO). The mercury concentration in hair samples obtained from the people living in the research location was considered to identify the health quality level of the people or as a chronic toxicity indicator. The highest mercury concentration--i.e. 17 ng/mg, was found in the gold mining respondents. Therefore, based on the total mercury concentration in the four indicators, the community in the gold mining area were more vulnerable to mercury than communities in non-gold mining areas. It was concluded that the community in gold mining area was more vulnerable to mercury contamination than the community in non-gold mining area.

  8. Characteristics of total gaseous mercury concentrations at a coastal area of the Yangtze Delta, China.

    Science.gov (United States)

    Diao, Chunyan; Li, Jianfeng; Zhang, Bin; Tang, Shichuang

    2017-03-01

    In this study, we report on total gaseous mercury (TGM) field observations made in the rural area of Shanghai, Chongming Island, China, from September 2009 to April 2012. The average TGM was 2.65 ± 1.73 ng m -3 in Chongming Island, which is higher than the TGM background value of the Northern Hemisphere (1.5-1.7 ng m -3 ); this indicates that to some extent, the Chongming area has been affected by anthropogenic mercury emissions. The observed TGM follows a seasonal pattern; concentrations are highest in winter, followed by autumn, summer, and spring. There is also a clear diurnal variation in TGM. All peak values appear between 7:00 and 9:00 in all four seasons; this appears to be the result of the height change in the atmospheric boundary layer that occurs between day and night. TGM concentrations in Chongming remain high in the westerly wind direction, especially in the southwest direction because of its low frequency, so the greatest source contribution to TGM in Chongming lies to the northwest. Wind speed is also a significant factor affecting TGM, and was negatively correlated with TGM concentrations. TGM is also closely related to carbon monoxide (CO) concentrations, indicating that TGM is impacted by human activities. The slope of the linear fitting of TGM and CO demonstrates that the contribution of noncoal source emissions to TGM in summer is greater than in autumn, mainly because the high temperature and intensive sunlight in summer increase mercury emissions from natural sources. Except for some studies in the coastal areas (e.g., Kang Hwa Island by Kim et al., 2006, An-Myun Island by Kim et al., 2002, and Okinawa by Chan et al., 2008), data specifically for coastal areas are lacking. Monitoring of total gaseous mercury (TGM) in the rural area of Shanghai, Chongming Island, can help us understand mercury distribution.

  9. Determination of dietary intake of total arsenic, inorganic arsenic and total mercury in the Chilean school meal program.

    Science.gov (United States)

    Bastías, J M; Bermúdez, M; Carrasco, J; Espinoza, O; Muñoz, M; Galotto, M J; Muñoz, O

    2010-10-01

    The dietary intake of total arsenic (tAs), inorganic arsenic (iAs) and total mercury (tHg) in lunch and breakfast servings provided by the Chilean School Meal Program (SMP) was estimated, using the duplicate-portion variant of the total diet study. Lunch and breakfast samples were collected from 65 schools throughout the country in 2006. The population sample was a group of girls and boys between 6 and 18 years old. The tAs concentration was measured via hydride-generation atomic absorption spectrometry. The total mercury concentration was measured via cold-vapor atomic absorption spectroscopy. The estimated iAs intake was 12.5% (5.4 μg/day) of the Provisional tolerable daily intake (PTDI) as proposed by the FAO/WHO, and the tHg intake was 13.2% (1.9 μg/day) of the PTDI as proposed by the FAO/WHO. It was therefore concluded that tAs, iAs and tHg intake from food provided by the SMP do not pose risks to student health.

  10. Determination of total mercury and methylmercury in biological samples by photochemical vapor generation

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Mariana A.; Ribeiro, Anderson S.; Curtius, Adilson J. [Universidade Federal de Santa Catarina, Departamento de Quimica, Florianopolis, SC (Brazil); Sturgeon, Ralph E. [National Research Council Canada, Institute for National Measurement Standards, Ottawa, ON (Canada)

    2007-06-15

    Cold vapor atomic absorption spectrometry (CV-AAS) based on photochemical reduction by exposure to UV radiation is described for the determination of methylmercury and total mercury in biological samples. Two approaches were investigated: (a) tissues were digested in either formic acid or tetramethylammonium hydroxide (TMAH), and total mercury was determined following reduction of both species by exposure of the solution to UV irradiation; (b) tissues were solubilized in TMAH, diluted to a final concentration of 0.125% m/v TMAH by addition of 10% v/v acetic acid and CH{sub 3}Hg{sup +} was selectively quantitated, or the initial digests were diluted to 0.125% m/v TMAH by addition of deionized water, adjusted to pH 0.3 by addition of HCl and CH{sub 3}Hg{sup +} was selectively quantitated. For each case, the optimum conditions for photochemical vapor generation (photo-CVG) were investigated. The photochemical reduction efficiency was estimated to be {proportional_to}95% by comparing the response with traditional SnCl{sub 2} chemical reduction. The method was validated by analysis of several biological Certified Reference Materials, DORM-1, DORM-2, DOLT-2 and DOLT-3, using calibration against aqueous solutions of Hg{sup 2+}; results showed good agreement with the certified values for total and methylmercury in all cases. Limits of detection of 6 ng/g for total mercury using formic acid, 8 ng/g for total mercury and 10 ng/g for methylmercury using TMAH were obtained. The proposed methodology is sensitive, simple and inexpensive, and promotes ''green'' chemistry. The potential for application to other sample types and analytes is evident. (orig.)

  11. Potential Impact of Rainfall on the Air-Surface Exchange of Total Gaseous Mercury from Two Common Urban Ground Surfaces

    Science.gov (United States)

    The impact of rainfall on total gaseous mercury (TGM) flux from pavement and street dirt surfaces was investigated in an effort to determine the influence of wet weather events on mercury transport in urban watersheds. Street dirt and pavement are common urban ground surfaces tha...

  12. Total mercury concentrations in surface water and sediments from Danube Delta lakes

    Directory of Open Access Journals (Sweden)

    TEODOROF Liliana

    2007-10-01

    Full Text Available The samples were collected from surface water and sediments of Danube Delta lakes, during april and may 2006. The sediments were digested with nitric acid, and the surface water with real aqua, at Microwave Oven Anton Paar and analised at FIMS 400 Perkin Elmer. The results show that the total mercury is compared with the maximum allowed limits according with Normative 161/2006.

  13. Mercury

    Science.gov (United States)

    ... that mercuric chloride and methylmercury are possible human carcinogens. top How does mercury affect children? Very young ... billion parts of drinking water (2 ppb). The Food and Drug Administration (FDA) has set a maximum ...

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

    Science.gov (United States)

    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.

  15. Survey of total mercury and methylmercury levels in edible fish from the Adriatic Sea.

    Science.gov (United States)

    Storelli, M M; Giacominelli-Stuffler, R; Storelli, A; D'Addabbo, R; Palermo, C; Marcotrigiano, G O

    2003-12-01

    Total mercury and methylmercury concentrations were measured in the muscle tissue of different fish species from the Adriatic Sea to ascertain whether the concentrations exceeded the maximum level fixed by the European Commission. Large species-dependent variability was observed. The highest total mercury mean concentrations were in benthic (0.20-0.76 microg g(-1) wet wt) and demersal fish (0.22-0.73 microg g(-1) wet wt), while pelagic species showed the lowest levels (0.09-0.23 microg g(-1) wet wt). In 15% of frost fish, in 42% of skate and in 30% of angler fish samples total mercury concentrations exceeded the maximum level fixed by the European Commission (Hg = 1 microg g(-1) wet wt); for the species for which the maximum level was set to 0.5 microg g(-1) wet wt, concentrations exceeding the prescribed legal limit were observed in 6.4% of bokkem, in 6.6% of pandora, in 20% of megrin, in 12.5% of four-spotted megrim, in 16% of striped mullet, in 5.0% of forkbeard and in 5.3% of picarel samples. In all the different species, mercury was present almost completely in the methylated form, with mean percentages between 70 and 100%. Weekly intake was estimated and compared with the provisional tolerable weekly intake recommended by the FAO/WHO Expert Committee on Food Additives. A high exposure was associated with the consumption of only skates, frost fish and angler fish, thought the consumption of the other species, such as, megrim, four spotted megrim, red fish striped mullet and forkbeard, resulted in a weekly intake slightly below the established provisional tolerable weekly intake.

  16. Determination of total and inorganic mercury in fish samples with on-line oxidation coupled to atomic fluorescence spectrometry

    International Nuclear Information System (INIS)

    Shao Lijun; Gan Wuer; Su Qingde

    2006-01-01

    An atomic fluorescence spectrometry system for determination of total and inorganic mercury with electromagnetic induction-assisted heating on-line oxidation has been developed. Potassium peroxodisulphate was used as the oxidizing agent to decompose organomercury compounds. Depending on the temperature selected, inorganic or total mercury could be determined with the same manifold. Special accent was put on the study of the parameters influencing the on-line digestion efficiency. The tolerance to the interference of coexisting ions was carefully examined in this system. Under optimal conditions, the detection limits (3σ) were evaluated to be 2.9 ng l -1 for inorganic mercury and 2.6 ng l -1 for total mercury, respectively. The relative standard deviations for 10 replicate determinations of 1.0 μg l -1 Hg were 2.4 and 3.2% for inorganic mercury and total mercury, respectively. The proposed method was successfully applied to the determination of total and inorganic mercury in fish samples

  17. Determination of inorganic mercury and total mercury in biological and environmental samples by flow injection-cold vapor-atomic absorption spectrometry using sodium borohydride as the sole reducing agent

    International Nuclear Information System (INIS)

    Rio Segade, Susana; Tyson, Julian F.

    2003-01-01

    A simple, fast, precise and accurate method to determine inorganic mercury and total mercury in biological and environmental samples was developed. The optimized flow-injection mercury system permitted the separate determination of inorganic mercury and total mercury using sodium borohydride as reducing agent. Inorganic mercury was selectively determined after reduction with 10 -4 % w/v sodium borohydride, while total mercury was determined after reduction with 0.75% w/v sodium borohydride. The calibration graphs were linear up to 30 ng ml -1 . The detection limits of the method based on three times the standard deviation of the blank were 24 and 3.9 ng l -1 for total mercury and inorganic mercury determination, respectively. The relative standard deviation was less than 1.5% for a 10 ng ml -1 mercury standard. As a means of checking method performance, deionized water and pond water samples were spiked with methylmercury and inorganic mercury; quantitative recovery for total mercury and inorganic mercury was obtained. The accuracy of the method was verified by analyzing alkaline and acid extracts of five biological and sediment reference materials. Microwave-assisted extraction procedures resulted in higher concentrations of recovered mercury species, lower matrix interference with mercury determination and less time involved in sample treatment than conventional extraction procedures. The standard addition method was only needed for calibration when biological samples were analyzed. The detection limits were in the range of 1.2-19 and 6.6-18 ng g -1 in biological and sediment samples for inorganic mercury and total mercury determination, respectively

  18. Accumulation of total mercury and methylmercury in rice plants collected from different mining areas in China

    International Nuclear Information System (INIS)

    Meng, Mei; Li, Bing; Shao, Jun-juan; Wang, Thanh; He, Bin; Shi, Jian-bo; Ye, Zhi-hong; Jiang, Gui-bin

    2014-01-01

    A total of 155 rice plants were collected from ten mining areas in three provinces of China (Hunan, Guizhou and Guangdong), where most of mercury (Hg) mining takes place in China. During the harvest season, whole rice plants were sampled and divided into root, stalk and leaf, husk and seed (brown rice), together with soil from root zone. Although the degree of Hg contamination varied significantly among different mining areas, rice seed showed the highest ability for methylmercury (MeHg) accumulation. Both concentrations of total mercury (THg) and MeHg in rice plants were significantly correlated with Hg levels in soil, indicating soil is still an important source for both inorganic mercury (IHg) and MeHg in rice plants. The obvious discrepancy between the distribution patterns of THg and MeHg reflected different pathways of IHg and MeHg accumulation. Water soluble Hg may play more important role in MeHg accumulation in rice plants. -- Highlights: • Distribution patterns indicated different pathways of IHg and MeHg accumulation. • Soil is an important source for both THg and MeHg to rice plants. • Water soluble Hg may play more important role in MeHg accumulation in rice plants. -- The distribution patterns indicate different pathways of IHg and MeHg accumulation in rice plants

  19. A SUMMARY OF TOTAL MERCURY CONCENTRATIONS IN FLORA AND FAUNA NEAR CONTAMINANT SOURCES IN THE GULF OF MEXICO

    Science.gov (United States)

    This report summarizes total mercury concentrations for environmental media collected from near-coastal areas including those impacted by contaminant sources common to the Gulf of Mexico. Water, sediment, fish, blue crabs, oysters, clams, mussels, periphyton and seagrasses were ...

  20. Estimation of uncertainty of a reference material for proficiency testing for the determination of total mercury in fish in nature

    International Nuclear Information System (INIS)

    Santana, L V; Sarkis, J E S; Ulrich, J C; Hortellani, M A

    2015-01-01

    We provide an uncertainty estimates for homogeneity and stability studies of reference material used in proficiency test for determination of total mercury in fish fresh muscle tissue. Stability was estimated by linear regression and homogeneity by ANOVA. The results indicate that the reference material is both homogeneous and chemically stable over the short term. Total mercury concentration of the muscle tissue, with expanded uncertainty, was 0.294 ± 0.089 μg g −1

  1. Mercury

    CERN Document Server

    Mahoney, T J

    2014-01-01

    This gazetteer and atlas on Mercury lists, defines and illustrates every named (as opposed to merely catalogued) object and term as related to Mercury within a single reference work. It contains a glossary of terminology used, an index of all the headwords in the gazetteer, an atlas comprising maps and images with coordinate grids and labels identifying features listed in the gazetteer, and appendix material on the IAU nomenclature system and the transcription systems used for non-roman alphabets. This book is useful for the general reader, writers and editors dealing with astronomical themes, and those astronomers concerned with any aspect of astronomical nomenclature.

  2. Mercury

    CERN Document Server

    Balogh, André; Steiger, Rudolf

    2008-01-01

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

  3. Total mercury concentrations in lionfish (Pterois volitans/miles) from the Florida Keys National Marine Sanctuary, USA.

    Science.gov (United States)

    Huge, Dane H; Schofield, Pamela J; Jacoby, Charles A; Frazer, Thomas K

    2014-01-15

    Strategies to control invasive lionfish in the western Atlantic and Caribbean are likely to include harvest and consumption. Until this report, total mercury concentrations had been documented only for lionfish from Jamaica, and changes in concentrations with increasing fish size had not been evaluated. In the Florida Keys, total mercury concentrations in dorsal muscle tissue from 107 lionfish ranged from 0.03 to 0.48 ppm, with all concentrations being less than the regulatory threshold for limited consumption. Mercury concentrations did not vary consistently with standard lengths or wet weights of lionfish. In 2010, lionfish from the upper Keys had mean concentrations that were 0.03-0.04 ppm higher than lionfish from the middle Keys, but mean concentrations did not differ consistently among years and locations. Overall, total mercury concentrations in lionfish were lower than those in several predatory fishes that support commercial and recreational fisheries in Florida. Published by Elsevier Ltd.

  4. Application of sodium carbonate prevents sulphur poisoning of catalysts in automated total mercury analysis

    Science.gov (United States)

    McLagan, David S.; Huang, Haiyong; Lei, Ying D.; Wania, Frank; Mitchell, Carl P. J.

    2017-07-01

    Analysis of high sulphur-containing samples for total mercury content using automated thermal decomposition, amalgamation, and atomic absorption spectroscopy instruments (USEPA Method 7473) leads to rapid and costly SO2 poisoning of catalysts. In an effort to overcome this issue, we tested whether the addition of powdered sodium carbonate (Na2CO3) to the catalyst and/or directly on top of sample material increases throughput of sulphur-impregnated (8-15 wt%) activated carbon samples per catalyst tube. Adding 5 g of Na2CO3 to the catalyst alone only marginally increases the functional lifetime of the catalyst (31 ± 4 g of activated carbon analyzed per catalyst tube) in relation to unaltered catalyst of the AMA254 total mercury analyzer (17 ± 4 g of activated carbon). Adding ≈ 0.2 g of Na2CO3 to samples substantially increases (81 ± 17 g of activated carbon) catalyst life over the unaltered catalyst. The greatest improvement is achieved by adding Na2CO3 to both catalyst and samples (200 ± 70 g of activated carbon), which significantly increases catalyst performance over all other treatments and enables an order of magnitude greater sample throughput than the unaltered samples and catalyst. It is likely that Na2CO3 efficiently sequesters SO2, even at high furnace temperatures to produce Na2SO4 and CO2, largely negating the poisonous impact of SO2 on the catalyst material. Increased corrosion of nickel sampling boats resulting from this methodological variation is easily resolved by substituting quartz boats. Overall, this variation enables an efficient and significantly more affordable means of employing automated atomic absorption spectrometry instruments for total mercury analysis of high-sulphur matrices.

  5. Total mercury distribution in different tissues of six species of freshwater fish from the Kpong hydroelectric reservoir in Ghana.

    Science.gov (United States)

    Atta, Alhassan; Voegborlo, Ray Bright; Agorku, Eric Selorm

    2012-05-01

    Total mercury concentrations were determined in seven tissues of 38 fish samples comprising six species from the Kpong hydroelectric reservoir in Ghana by cold vapour atomic absorption spectrometry technique using an automatic mercury analyzer. Mercury concentration in all the tissues ranged from 0.005 to 0.022 μg/g wet weight. In general, the concentration of mercury in all the tissues were decreasing in the order; liver > muscle > intestine > stomach > gonad > gill > swim bladder. Mercury concentration was generally greater in the tissues of high-trophic-level fish such as Clarotes laticeps, Mormyrops anguilloides and Chrysichthys aurutus whereas low-trophic-level fish such as Oreochromis niloticus recorded low mercury concentration in their tissues. The results obtained for total mercury concentration in the muscle tissues analysed in this study are below the WHO/FAO threshold limit of 0.5 μg/g. This suggests that the exposure of the general public to Hg through fish consumption can be considered negligible.

  6. Total Mercury and Methylmercury Contamination in Fish from Sites along the Elbe River

    Directory of Open Access Journals (Sweden)

    P. Maršálek

    2006-01-01

    Full Text Available The aim of the study was to evaluate total mercury Hg and methylmercury MeHg contamination in muscle tissues of fish collected in 2002 from the Labe (Elbe river at sites upstream of Pardubice and downstream of Pardubice and Hřensko, and in 2004 from the Labe river upstream and downstream of the Spolana factory in Neratovice, and from the Vltava river downstream of Lenora. Eighty eight fish of the following species were sampled: bream (Abramis brama L., perch (Perca fluviatilis L., chub (Leuciscus cephalus L. and barbel (Barbus barbus L.. Total mercury content in chub, perch and bream was in the range of 0.05 - 1.96 mg kg-1 w.w., 0. 09 - 1.46 mg kg-1 w.w. and 0.35 - 0.82 mg kg-1 w.w., respectively. Methylmercury content in chub, perch and bream was in the range of 0.04 - 2.11 mg kg-1 w.w., 0.1 - 1.73 mg kg-1 w.w. and 0.371 - 0.650 mg kg-1 w.w., respectively. Significant correlation (p p < 0.05 between THg and MeHg contents were found between individual sites. In 2002, for example, the most contaminated fish were found downstream of Pardubice, followed by fish from upstream of Pardubice and from Hřensko. In 2004, fish from downstream and upstream of the Spolana factory in Neratovice were more contaminated than fish from the Vltava river downstream of Lenora. The methylmercury-tototal mercury ratio in muscle tissue was close to 1.0.

  7. The determination of methylmercury, total mercury and total selenium in human hair

    International Nuclear Information System (INIS)

    1987-01-01

    This Reference Method describes the determination of methylmercury in human hair by gas liquid chromatography. It is designed for biological monitoring of selected individuals and population groups with a possible intake of methylmercury exceeding the recommended Provisional Tolerable Weekly Intake (PTWI) through contaminated seafood, as part of a project on the evaluation of methylmercury in Mediterranean populations and related health hazards. The method, however, is also applicable to other regions. The method involves direct determination of methylmercury by gas liquid chromatography. The sample is disintegrated in a solution of sodium hydroxide, methylmercury is extracted from an aliquot of the solution into toluene and, after purification, a small volume is injected into a chromatographic column, filled with polyethyleneglycol succinate on Diatomite AW. Methylmercury in the gaseous mixture is detected with an electron capture detector and its amount determined by comparing the peak height with those of appropriate standards. The next Reference Method describes the determination of selenium in human hair (and other indicative tissues) by gas liquid chromatography and is designed for biological monitoring of selected individuals and population groups in the Mediterranean region with a possible intake of methylmercury exceeding the recommended Provisional Tolerable Weekly Intake (PTWI) through contaminated seafood. The data are intended to establish a possible correlation between methylmercury intake and levels of selenium in the subjects monitored. Selenium in the solvent phase is determined by gas liquid chromatography using an electron capture detector. The above method has been selected because selenium is determined in conjunction with methylmercury, both of which require competence in gas chromatographic techniques. Reliable result for total selenium, however, will also be obtained by the following techniques: a) Atomic absorption spectrophotometry; b

  8. Influence of the forest canopy on total and methyl mercury deposition in the boreal forest

    Science.gov (United States)

    E.L. Witt; R.K. Kolka; E.A. Nater; T.R. Wickman

    2009-01-01

    Atmospheric mercury deposition by wet and dry processes contributes mercury to terrestrial and aquatic systems. Factors influencing the amount of mercury deposited to boreal forests were identified in this study. Throughfall and open canopy precipitation samples were collected in 2005 and 2006 using passive precipitation collectors from pristine sites located across...

  9. Distribution of total mercury, methyl mercury and selenium in pod of killer whales (Orcinus Orca) stranded in the northern area of Japan: Comparison of mature females with calves

    Energy Technology Data Exchange (ETDEWEB)

    Endo, Tetsuya [Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, 1757 Ishikari-Tobetsu, Hokkaido 061-0293 (Japan)]. E-mail: endotty@hoku-iryo-u.ac.jp; Kimura, Osamu [Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, 1757 Ishikari-Tobetsu, Hokkaido 061-0293 (Japan); Hisamichi, Yohsuke [Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, 1757 Ishikari-Tobetsu, Hokkaido 061-0293 (Japan); Minoshima, Yasuhiko [Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, 1757 Ishikari-Tobetsu, Hokkaido 061-0293 (Japan); Haraguchi, Koichi [Daiichi College of Pharmaceutical Sciences, 22-1 Tamagawa-Cho, Minami-Ku, Fukuoka 815-8511 (Japan); Kakumoto, Chiharu [Marine Wildlife Center of JAPAN - Incorporated Non Profit Organization/NPO, 1-35-103, N21W6 Kita-ku, Sapporo, Hokkaido 001-0021 (Japan); Kobayashi, Mari [Marine Wildlife Center of JAPAN - Incorporated Non Profit Organization/NPO, 1-35-103, N21W6 Kita-ku, Sapporo, Hokkaido 001-0021 (Japan)

    2006-11-15

    Total mercury (T-Hg) and selenium (Se) concentrations in liver, kidney and muscle from a pod of killer whales including five mature females and three calves stranded in the northern area of Japan were analyzed. In the mature female, contamination level of T-Hg in the liver sample (62.2 {+-} 21.9 {mu}g/wet g) was markedly higher than that in kidney sample and muscle sample. The molar ratio of T-Hg to Se in the liver sample was approximately 1, and those in the kidney and muscle samples were markedly lower than 1. These results suggest that the formation of HgSe compound increases the hepatic accumulation of mercury (Hg). In contrast, contamination level of T-Hg in the calf organs was much lower than that in the mature female organs. These results suggest that the transfer of Hg from the mother to the fetus via placenta and/or to calf via milk is trace. - Total mercury, methyl mercury and selenium concentrations in liver, kidney and muscle from a pod of killer whales stranded in the northern area of Japan were analyzed.

  10. Distribution of total mercury, methyl mercury and selenium in pod of killer whales (Orcinus Orca) stranded in the northern area of Japan: Comparison of mature females with calves

    International Nuclear Information System (INIS)

    Endo, Tetsuya; Kimura, Osamu; Hisamichi, Yohsuke; Minoshima, Yasuhiko; Haraguchi, Koichi; Kakumoto, Chiharu; Kobayashi, Mari

    2006-01-01

    Total mercury (T-Hg) and selenium (Se) concentrations in liver, kidney and muscle from a pod of killer whales including five mature females and three calves stranded in the northern area of Japan were analyzed. In the mature female, contamination level of T-Hg in the liver sample (62.2 ± 21.9 μg/wet g) was markedly higher than that in kidney sample and muscle sample. The molar ratio of T-Hg to Se in the liver sample was approximately 1, and those in the kidney and muscle samples were markedly lower than 1. These results suggest that the formation of HgSe compound increases the hepatic accumulation of mercury (Hg). In contrast, contamination level of T-Hg in the calf organs was much lower than that in the mature female organs. These results suggest that the transfer of Hg from the mother to the fetus via placenta and/or to calf via milk is trace. - Total mercury, methyl mercury and selenium concentrations in liver, kidney and muscle from a pod of killer whales stranded in the northern area of Japan were analyzed

  11. Ultraviolet absorbance as a proxy for total dissolved mercury in streams

    International Nuclear Information System (INIS)

    Dittman, Jason A.; Shanley, James B.; Driscoll, Charles T.; Aiken, George R.; Chalmers, Ann T.; Towse, Janet E.

    2009-01-01

    Stream water samples were collected over a range of hydrologic and seasonal conditions at three forested watersheds in the northeastern USA. Samples were analyzed for dissolved total mercury (THg d ), DOC concentration and DOC composition, and UV 254 absorbance across the three sites over different seasons and flow conditions. Pooling data from all sites, we found a strong positive correlation of THg d to DOC (r 2 = 0.87), but progressively stronger correlations of THg d with the hydrophobic acid fraction (HPOA) of DOC (r 2 = 0.91) and with UV 254 absorbance (r 2 = 0.92). The strength of the UV 254 absorbance-THg d relationship suggests that optical properties associated with dissolved organic matter may be excellent proxies for THg d concentration in these streams. Ease of sample collection and analysis, the potential application of in-situ optical sensors, and the possibility for intensive monitoring over the hydrograph make this an effective, inexpensive approach to estimate THg d flux in drainage waters. - Ultraviolet absorbance measurements are a cost-effective proxy to estimate dissolved mercury concentration in stream water.

  12. Influence of eutrophication on the distribution of total mercury and methylmercury in hydroelectric reservoirs.

    Science.gov (United States)

    Meng, Bo; Feng, X B; Chen, C X; Qiu, G L; Sommar, J; Guo, Y N; Liang, P; Wan, Q

    2010-01-01

    The distribution of mercury (Hg) and the characteristics of its methylation were investigated in Wujiangdu (WJD) and Yinzidu (YZD) reservoirs in Guizhou province, China. The two reservoirs are characterized by high and low levels of primary productivity, respectively. Mercury species in water samples from depth profiles in both reservoirs and from interface water in the WJD were analyzed each season during 2007. The concentrations of total Hg (HgT(unf)) and methylmercury (MeHgT(unf)) in unfiltered water samples from the WJD varied from 3.0 to 18 pmol dm(-3) and from 0.17 to 15 pmol dm(-3), respectively; ranges were 2.0 to 9.5 pmol dm(-3) for HgT(unf) and 0.14 to 2.2 pmol dm(-3) for MeHgT(unf) in the YZD. Elevated methylmercury concentrations in water samples from the bottom water and water-sediment interface demonstrated an active net Hg methylation in the downstream reach of the WJD. There was no discernable Hg methylation occurring in the YZD, nor in the upstream and middle reaches of the WJD. The results suggest that high primary productivity resulting from cage aquaculture activities in the WJD is an important control on Hg methylation in the reservoir, increasing the concentrations of MeHg in water in the Wujiang River basin Southwestern China.

  13. Determination of total mercury and methylmercury in the head hair of pregnant Vietnamese women

    International Nuclear Information System (INIS)

    Nguyen Tac Anh; Ho Manh Dung; Pham Hoang Ha; Nguyen Thuy Sy; Le Tat Mua

    1995-01-01

    Neutron Activation Analysis (NAA), including both the non-destructive (Instrumental NAA) and destructive (Radiochemical NAA) forms, is used as the principal technique to determine total mercury (T-Hg) and methylmercury (MeHg) in samples of human head hair. Head hair samples taken from pregnant women has been the focus for sample collection in this project. In addition, a special population group (Buddhist monks) and a normal population (control) group have also been selected for study. The defined population groups are residing in distinct regions which represent highland, coastal and industrial areas in Vietnam. Preliminary results from the determination of T-Hg and MeHg in hair samples from the defined groups indicate that the consumption of fish and seafood products is the main source of intake of MeHg; this agrees with the results from other investigators. The mean T-Hg in human hair samples from Ho Chi Minh City (an industrial region) was statistically higher than the corresponding mean values from samples taken in Dalat and Nha Trang cities, which suggest that industrial activities may be discharging an appreciable amount of mercury into the environment around Ho Chi Minh City. (author)

  14. Nonflame atomic absorption determination of total mercury in natural waters using an HS-3 mercury-hydride system

    Energy Technology Data Exchange (ETDEWEB)

    Evdokimova, E.V.; Solov`eva, M.Kh.; Telegin, G.F. [Institute of Problems in the Technology of Microelectronics and High-Purity Materials, Moscow (Russian Federation)

    1995-02-01

    A method for nonflame atomic absorption determination of mercury with a detection limit of 1 x 10{sup -3} {mu}g/ml in natural waters without preconcentration is described. The method can be applied successfully in analysis of the environment.

  15. Levels of total mercury in marine organisms from Adriatic Sea, Italy.

    Science.gov (United States)

    Perugini, Monia; Visciano, Pierina; Manera, Maurizio; Zaccaroni, Annalisa; Olivieri, Vincenzo; Amorena, Michele

    2009-08-01

    The presence of total mercury in fish, crustacean and cephalopod from Adriatic Sea, was investigated. The highest concentrations were observed in decreasing order in: Norway lobster (0.97 +/- 0.24 mg/kg; mean +/- SE), European hake (0.59 +/- 0.14 mg/kg), red mullet (0.48 +/- 0.09 mg/kg), blue whiting (0.38 +/- 0.09 mg/kg), Atlantic mackerel (0.36 +/- 0.08 mg/kg) and European flying squid (0.25 +/- 0.03 mg/kg). A significant difference (p fish and fishery products can exceed the maximum levels and stress the need of more information for consumers in particular for people that eat large amount of fish.

  16. Comparison of total mercury and methylmercury cycling at five sites using the small watershed approach

    Energy Technology Data Exchange (ETDEWEB)

    Shanley, James B. [US Geological Survey, PO Box 628, Montpelier, VT 05601 (United States)], E-mail: jshanley@usgs.gov; Alisa Mast, M. [US Geological Survey, MS 415 Denver Federal Center, Denver, CO 80225 (United States)], E-mail: mamast@usgs.gov; Campbell, Donald H. [US Geological Survey, MS 415 Denver Federal Center, Denver, CO 80225 (United States)], E-mail: dhcampbe@usgs.gov; Aiken, George R. [US Geological Survey, 3215 Marine Street, Suite E-127, Boulder, CO 80303 (United States)], E-mail: graiken@usgs.gov; Krabbenhoft, David P. [US Geological Survey, 8505 Research Way, Middleton, WI 53562 (United States)], E-mail: dpkrabbe@usgs.gov; Hunt, Randall J. [US Geological Survey, 8505 Research Way, Middleton, WI 53562 (United States)], E-mail: rjhunt@usgs.gov; Walker, John F. [US Geological Survey, 8505 Research Way, Middleton, WI 53562 (United States)], E-mail: jfwalker@usgs.gov; Schuster, Paul F. [US Geological Survey, 3215 Marine Street, Suite E-127, Boulder, CO 80303 (United States)], E-mail: pschuste@usgs.gov; Chalmers, Ann [US Geological Survey, PO Box 628, Montpelier, VT 05601 (United States)], E-mail: chalmers@usgs.gov; Aulenbach, Brent T. [US Geological Survey, 3039 Amwiler Road, Suite 130, Atlanta, GA 30360 (United States)], E-mail: btaulenb@usgs.gov; Peters, Norman E. [US Geological Survey, 3039 Amwiler Road, Suite 130, Atlanta, GA 30360 (United States)], E-mail: nepeters@usgs.gov; Marvin-DiPasquale, Mark [US Geological Survey, 345 Middlefield Rd., MS 480, Menlo Park, CA 94025 (United States)], E-mail: mmarvin@usgs.gov; Clow, David W. [US Geological Survey, MS 415 Denver Federal Center, Denver, CO 80225 (United States)], E-mail: dwclow@usgs.gov; Shafer, Martin M. [Environmental Chemistry and Technology and Wisconsin State Laboratory of Hygiene, University of Wisconsin, Madison, WI 53706 (United States)], E-mail: mmshafer@wisc.edu

    2008-07-15

    The small watershed approach is well-suited but underutilized in mercury research. We applied the small watershed approach to investigate total mercury (THg) and methylmercury (MeHg) dynamics in streamwater at the five diverse forested headwater catchments of the US Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) program. At all sites, baseflow THg was generally less than 1 ng L{sup -1} and MeHg was less than 0.2 ng L{sup -1}. THg and MeHg concentrations increased with streamflow, so export was primarily episodic. At three sites, THg and MeHg concentration and export were dominated by the particulate fraction in association with POC at high flows, with maximum THg (MeHg) concentrations of 94 (2.56) ng L{sup -1} at Sleepers River, Vermont; 112 (0.75) ng L{sup -1} at Rio Icacos, Puerto Rico; and 55 (0.80) ng L{sup -1} at Panola Mt., Georgia. Filtered (<0.7 {mu}m) THg increased more modestly with flow in association with the hydrophobic acid fraction (HPOA) of DOC, with maximum filtered THg concentrations near 5 ng L{sup -1} at both Sleepers and Icacos. At Andrews Creek, Colorado, THg export was also episodic but was dominated by filtered THg, as POC concentrations were low. MeHg typically tracked THg so that each site had a fairly constant MeHg/THg ratio, which ranged from near zero at Andrews to 15% at the low-relief, groundwater-dominated Allequash Creek, Wisconsin. Allequash was the only site with filtered MeHg consistently above detection, and the filtered fraction dominated both THg and MeHg. Relative to inputs in wet deposition, watershed retention of THg (minus any subsequent volatilization) was 96.6% at Allequash, 60% at Sleepers, and 83% at Andrews. Icacos had a net export of THg, possibly due to historic gold mining or frequent disturbance from landslides. Quantification and interpretation of Hg dynamics was facilitated by the small watershed approach with emphasis on event sampling. - High-flow sampling reveals strong contrasts in total

  17. Seasonal Variations in the Use of Profundal Habitat among Freshwater Fishes in Lake Norsjø, Southern Norway, and Subsequent Effects on Fish Mercury Concentrations

    Directory of Open Access Journals (Sweden)

    Tom Robin Olk

    2016-11-01

    Full Text Available This study is based on monthly sampling of fish from grates mounted at an industrial water intake, located at a depth of 50 m in Lake Norsjø (Southern Norway during the year 2014, to investigate seasonal variations in the use of the profundal habitat and subsequent variations in total Hg-concentrations in profundal fish. Data on various fish present in a cold and dark hypolimnion of a large, deep, dimictic lake within the upper temperate zone of the Northern Hemisphere are rare. While predominant species such as A. charr (Salvelinus alpinus and E. smelt (Osmerus eperlanus were continuously present in this habitat, whitefish (Coregonus lavaretus occupied this habitat primarily during wintertime, while other common species like brown trout (Salmo trutta, perch (Perca fluviatilis and northern pike (Esox lucius were almost absent. Besides stomach analyses (diet and biometry, stable isotope analyses (δ15N and δ13C and total mercury (Tot-Hg analyses were carried out on the caught fish. The δ13C signature and stomach analyses revealed a combined profundal-pelagic diet for all three species, A. charr with the most profundal-based diet. Length was the strongest predictor for Hg in whitefish and A. charr, while age was the strongest explanatory variable for Hg in E. smelt. A. charr was the only species exhibiting seasonal variation in Hg, highest during winter and spring.

  18. Total mercury in muscles and liver of Mugil spp. from three coastal lagoons of NW Mexico: concentrations and risk assessment.

    Science.gov (United States)

    Delgado-Alvarez, C G; Frías-Espericueta, M G; Ruelas-Inzunza, J; Becerra-Álvarez, M J; Osuna-Martínez, C C; Aguilar-Juárez, M; Osuna-López, J I; Escobar-Sánchez, O; Voltolina, D

    2017-07-01

    Total mercury (Hg) concentrations were determined by atomic absorption spectrophotometry in muscles and liver of composite samples of Mugil cephalus and M. curema collected during November 2013 and in January, April, and July 2014 from the coastal lagoons Altata-Ensenada del Pabellón (AEP), Ceuta (CEU), and Teacapán-Agua Brava (TAG) of Sinaloa State. The mean Hg contents and information on local consumption were used to assess the possible risk caused by fish ingestion. Mean total mercury levels in the muscles ranged from 0.11 to 0.39 μg/g, while the range for liver was 0.12-3.91 μg/g. The mean Hg content of the liver was significantly (p mercury calculated for the younger age classes of one fishing community were >1, indicating a possible risk for some fishing communities of the Mexican Pacific coast.

  19. Distribution of Total and Organic Mercury in Superficial Soils in the Upper Manzanares River Watershed, Sucre State, Venezuela

    Directory of Open Access Journals (Sweden)

    Yahsé Rojas Challa

    2008-01-01

    Full Text Available Total and organic mercury contents were determined from samples of surface soils (0-5 cm, sieved at ≤ 63µm, collected from 10 different locations in the upper Manzanares River watershed, using cold vapor atomic absorption spectroscopy. Methylmercury was determined using a HPLC-UV detector. The mean total mercury concentration was 1.3 μg.g-1, a value permitted by the Canadian environment quality guidelines for farming soils, but high for European standards. Using certified reference materials, we verified that a modification of the method described by Qian et al. (2000 was effective for organic mercury extraction, with a recovery of 92.17% for DORM-2 and 92.11% for TORT-2. This modified method was applied to soil samples, obtaining concentrations of 0.5-1.0 μg.g-1 of organic mercury. The parameters for determining methylmercury using HPLC-UV were optimized; the best results were obtained with a 4.6 mm x 25 cm Zorbax CN column, with a mobile phase of 70/30 V/V of methanol: ammonium acetate 0.05 mol.l-1, with a flow rate of 0.5 ml.min-1; the methylmercury was detected at 4.99 min retention time. Methylmercury was not found in the soil samples. Using the certified reference material we proved that the method used produced reliable results. The analysis confirmed the existence of mercury in this farming area.

  20. Comparison of total mercury and methylmercury cycling at five sites using the small watershed approach

    Science.gov (United States)

    Shanley, J.B.; Alisa, Mast M.; Campbell, D.H.; Aiken, G.R.; Krabbenhoft, D.P.; Hunt, R.J.; Walker, J.F.; Schuster, P.F.; Chalmers, A.; Aulenbach, Brent T.; Peters, N.E.; Marvin-DiPasquale, M.; Clow, D.W.; Shafer, M.M.

    2008-01-01

    The small watershed approach is well-suited but underutilized in mercury research. We applied the small watershed approach to investigate total mercury (THg) and methylmercury (MeHg) dynamics in streamwater at the five diverse forested headwater catchments of the US Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) program. At all sites, baseflow THg was generally less than 1 ng L-1 and MeHg was less than 0.2 ng L-1. THg and MeHg concentrations increased with streamflow, so export was primarily episodic. At three sites, THg and MeHg concentration and export were dominated by the particulate fraction in association with POC at high flows, with maximum THg (MeHg) concentrations of 94 (2.56) ng L-1 at Sleepers River, Vermont; 112 (0.75) ng L-1 at Rio Icacos, Puerto Rico; and 55 (0.80) ng L-1 at Panola Mt., Georgia. Filtered (Colorado, THg export was also episodic but was dominated by filtered THg, as POC concentrations were low. MeHg typically tracked THg so that each site had a fairly constant MeHg/THg ratio, which ranged from near zero at Andrews to 15% at the low-relief, groundwater-dominated Allequash Creek, Wisconsin. Allequash was the only site with filtered MeHg consistently above detection, and the filtered fraction dominated both THg and MeHg. Relative to inputs in wet deposition, watershed retention of THg (minus any subsequent volatilization) was 96.6% at Allequash, 60% at Sleepers, and 83% at Andrews. Icacos had a net export of THg, possibly due to historic gold mining or frequent disturbance from landslides. Quantification and interpretation of Hg dynamics was facilitated by the small watershed approach with emphasis on event sampling. ?? 2008 Elsevier Ltd. All rights reserved.

  1. Total mercury, cadmium and lead levels in main export fish of Sri Lanka.

    Science.gov (United States)

    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. Total mercury, methyl mercury, and heavy metal concentrations in Hyeongsan River and its tributaries in Pohang city, South Korea.

    Science.gov (United States)

    Bailon, Mark Xavier; David, Anneschel Sheehan; Park, Yeongeon; Kim, Eunhee; Hong, Yongseok

    2018-04-11

    Heavy metal contamination in aquatic systems is a big problem in many areas around the world. In 2016, high mercury concentrations were reported in bivalves (Corbicula leana) and sediments near the confluence of the Hyeongsan River and Chilseong Creek located in Pohang, a steel industrial city in the south-east coast of the Korean peninsula. Given that both the Chilseong and Gumu creeks run through the Pohang industrial complex and ultimately flow to the Hyeongsan River, it is imperative to determine if the industrial effluents have any impact on the mercury contamination in these two streams and the Hyeongsan River. In this work, we investigated the concentration levels of different heavy metals using cold vapor atomic fluorescence spectroscopy and inductively coupled plasma-mass spectroscopy. The metal concentration in the water samples from the Hyeongsan River, Gumu Creek, and Chilseong Creek did not exceed the limits for drinking water quality set by the US EPA and World Health Organization. However, the sediment samples were found to be heavily contaminated by Hg with levels exceeding the toxic effect threshold. Gumu Creek was found to be heavily contaminated. The concentrations of the different heavy metals increased downstream, and the samples collected from the sites in the Hyeongsan River near the Gumu Creek, an open channel for wastewater discharge of companies in the Pohang Industrial Complex, showed higher contamination levels, indicating that the effluents from the industrial complex are a possible source of contamination in the river.

  3. The interaction rainfall vs. weight as determinant of total mercury concentration in fish from a tropical estuary

    International Nuclear Information System (INIS)

    Barletta, M.; Lucena, L.R.R.; Costa, M.F.; Barbosa-Cintra, S.C.T.; Cysneiros, F.J.A.

    2012-01-01

    Mercury loads in tropical estuaries are largely controlled by the rainfall regime that may cause biodilution due to increased amounts of organic matter (both live and non-living) in the system. Top predators, as Trichiurus lepturus, reflect the changing mercury bioavailability situations in their muscle tissues. In this work two variables [fish weight (g) and monthly total rainfall (mm)] are presented as being important predictors of total mercury concentration (T-Hg) in fish muscle. These important explanatory variables were identified by a Weibull Regression model, which best fit the dataset. A predictive model using readily available variables as rainfall is important, and can be applied for human and ecological health assessments and decisions. The main contribution will be to further protect vulnerable groups as pregnant women and children. Nature conservation directives could also improve by considering monitoring sample designs that include this hypothesis, helping to establish complete and detailed mercury contamination scenarios. - Highlights: ► Questions previous statistical approaches that used heterocedastic data after transformation. ► Corroborates other works that pointed seasonal variations of the mercury burden in fish muscle. ► Defines rainfall as a major driver of mercury in predatory fish at tropical latitudes. ► Progresses in environmental data analysis and steps forward from previous approaches to Hg in fish. ► Proposes a model to predict scenarios of Hg in fish as a function of biological and environmental variables. - The Weibull Regression model was the most appropriate fit for T-Hg in fish and therefore more ecological insights emerged from previous data.

  4. Reducing surface water total and methyl mercury concentrations and bioavailability using a coagulation-wetland system

    Science.gov (United States)

    Kraus, T. E.; Fleck, J.; Henneberry, Y. K.; Stumpner, E. B.; Krabbenhoft, D. P.; Bachand, P.; Randall, P.

    2013-12-01

    With the recent passage of laws regulating concentrations and loads of mercury (Hg) in surface waters, there is a need to develop management practices that will reduce the export of Hg from both point and non-point sources. Coagulation with metal based salts to remove particles and dissolved organic matter (DOM) from solution is a practice commonly employed by drinking water utilities. Because dissolved Hg is associated with particles and DOM, it follows that Hg should also be removed during the coagulation process and end up associated with the organo-metal precipitate, termed flocculate (floc). The effectiveness of iron- and aluminum-based coagulants for removing both inorganic and methyl mercury (IHg and MeHg, respectively) from solution was demonstrated in laboratory studies conducted on agricultural drainage waters of the Sacramento-San Joaquin Delta: dissolved concentrations of MeHg decreased by 80% while IHg decreased by 97% following coagulation. To test the field application of this technology, samples were collected from the inflows and outflows of wetland treatment cells constructed in the central Delta of California. This replicated field experiment includes three replicates each of three inflow waters treatments: (1) iron sulfate addition, (2) polyaluminum chloride addition, and (3) untreated controls. Water entering and exiting the nine treatment cells was sampled approximately monthly over a 1-year period for total Hg and MeHg in both the dissolved and particulate aqueous phases. Initial results confirm that coagulant addition is removing Hg (total and methyl, particulate and dissolved) from solution and sequestering it in the floc. Seasonal effects on DOM concentration and other factors appear to effect whether passage through the wetland cells alters surface water dissolved organic carbon (DOC) and Hg concentrations. Related studies will examine whether the presence of the floc affects the production and fate of MeHg within the wetland cells. If

  5. Watershed and discharge influences on the phase distribution and tributary loading of total mercury and methylmercury into Lake Superior

    International Nuclear Information System (INIS)

    Babiarz, Christopher; Hoffmann, Stephen; Wieben, Ann; Hurley, James; Andren, Anders; Shafer, Martin; Armstrong, David

    2012-01-01

    Knowledge of the partitioning and sources of mercury are important to understanding the human impact on mercury levels in Lake Superior wildlife. Fluvial fluxes of total mercury (Hg T ) and methylmercury (MeHg) were compared to discharge and partitioning trends in 20 sub-basins having contrasting land uses and geological substrates. The annual tributary yield was correlated with watershed characteristics and scaled up to estimate the basin-wide loading. Tributaries with clay sediments and agricultural land use had the largest daily yields with maxima observed near the peak in water discharge. Roughly 42% of Hg T and 57% of MeHg was delivered in the colloidal phase. Tributary inputs, which are confined to near-shore zones of the lake, may be more important to the food-web than atmospheric sources. The annual basin-wide loading from tributaries was estimated to be 277 kg yr −1 Hg T and 3.4 kg yr −1 MeHg (5.5 and 0.07 mg km −2 d −1 , respectively). - Highlights: ► The highest mercury yields occurred during spring melt except in forested watersheds. ► Roughly half of the mercury yield occurred in the colloidal phase. ► About 277 kg of Hg T and 3.4 kg of MeHg were delivered annually via tributaries. ► Whole-water MeHg loading was roughly equivalent to the estimated atmospheric loading. ► Watersheds with peat, loam or sandy soils deliver more MeHg than those with clays. - Tributary inputs, which are confined to the near-shore zones of Lake Superior, provide more mercury to these sensitive aquatic habitats than direct atmospheric deposition.

  6. Ultraviolet absorbance as a proxy for total dissolved mercury in streams

    Science.gov (United States)

    Dittman, J.A.; Shanley, J.B.; Driscoll, C.T.; Aiken, G.R.; Chalmers, A.T.; Towse, J.E.

    2009-01-01

    Stream water samples were collected over a range of hydrologic and seasonal conditions at three forested watersheds in the northeastern USA. Samples were analyzed for dissolved total mercury (THgd), DOC concentration and DOC composition, and UV254 absorbance across the three sites over different seasons and flow conditions. Pooling data from all sites, we found a strong positive correlation of THgd to DOC (r2 = 0.87), but progressively stronger correlations of THgd with the hydrophobic acid fraction (HPOA) of DOC (r2 = 0.91) and with UV254 absorbance (r2 = 0.92). The strength of the UV254 absorbance-THgd relationship suggests that optical properties associated with dissolved organic matter may be excellent proxies for THgd concentration in these streams. Ease of sample collection and analysis, the potential application of in-situ optical sensors, and the possibility for intensive monitoring over the hydrograph make this an effective, inexpensive approach to estimate THgd flux in drainage waters. ?? 2009 Elsevier Ltd.

  7. Tracing Sources of Total Gaseous Mercury to Yongheung Island off the Coast of Korea

    Directory of Open Access Journals (Sweden)

    Gang S. Lee

    2014-04-01

    Full Text Available In this study, total gaseous mercury (TGM concentrations were measured on Yongheung Island off the coast of Korea between mainland Korea and Eastern China in 2013. The purpose of this study was to qualitatively evaluate the impact of local mainland Korean sources and regional Chinese sources on local TGM concentrations using multiple tools including the relationship with other pollutants, meteorological data, conditional probability function, backward trajectories, and potential source contribution function (PSCF receptor modeling. Among the five sampling campaigns, two sampling periods were affected by both mainland Korean and regional sources, one was caused by mainland vehicle emissions, another one was significantly impacted by regional sources, and, in the remaining period, Hg volatilization from oceans was determined to be a significant source and responsible for the increase in TGM concentration. PSCF identified potential source areas located in metropolitan areas, western coal-fired power plant locations, and the southeastern industrial area of Korea as well as the Liaoning province, the largest Hg emitting province in China. In general, TGM concentrations generally showed morning peaks (07:00~12:00 and was significantly correlated with solar radiation during all sampling periods.

  8. Aerosol trace metals, particle morphology and total gaseous mercury in the atmosphere of Oxford, UK

    Science.gov (United States)

    Witt, M. L. I.; Meheran, N.; Mather, T. A.; de Hoog, J. C. M.; Pyle, D. M.

    2010-04-01

    An investigation of atmospheric trace metals was conducted in Oxford, UK, a small city ˜60 miles northwest of London, in 2007 and 2008. Concentrations of Sr, Mo, Cd, Pb, V, Cr, Mn, Fe, Co, Ni, Cu and Zn in aerosol were measured in bulk and size segregated samples. In addition, total gaseous mercury (TGM) concentrations were monitored semi-continuously by cold vapour-atomic fluorescence spectroscopy. Metal concentrations in Oxford were intermediate between previously reported levels of UK rural and urban areas for most metals studied and levels of Cd, Ni and Pb were within European guidelines. Metal concentrations appeared to be influenced by higher traffic volume on a timescale of hours. The influence of traffic on the aerosols was also suggested by the observation of carbonaceous particles via scanning electron microscopy (SEM). Air mass back trajectories suggest air masses arriving in Oxford from London and mainland Europe contained the highest metal concentrations. Aerosol samples collected over Bonfire Weekend, a period of intense firework use and lighting of bonfires in the UK, showed metal concentrations 6-46 times higher than at other times. Strontium, a tracer of firework release, was present at higher concentrations and showed a change in its size distribution from the coarse to fine mode over Bonfire Weekend. The presence of an abundance of spherical Sr particles was also confirmed in SEM images. The average TGM concentration in Oxford was 3.17 ng m -3 (st. dev. 1.59) with values recorded between 1.32 and 23.2 ng m -3. This is a higher average value than reported from nearby rural locations, although during periods when air was arriving from the west, similar concentrations to these rural areas were seen in Oxford. Comparison to meteorological data suggests that TGM in Oxford's air is highest when wind is arriving from the east/southeast. This may be due to emissions from London/mainland Europe with a possible contribution from emissions from a local

  9. EVALUATION OF TOTAL MERCURY CONTENT IN MUSCLE TISSUE OF MARINE FISH AND ANIMALS

    OpenAIRE

    Daniel Bajčan; Július Árvay; Janette Musilová

    2013-01-01

    Nowdays, a degree of contamination by heavy metals can be observed in the environment. Heavy metals have serious effects on all living organisms because they can accumulate in lethal or sublethal concentrations in the various parts of food chain and so they can cause different health problems like cardiovascular and cancer diseases. Marine fish and animals are one of the bigges source of mercury in human food. Therefore this work is focused to the rate of mercury content in muscle tisuues of ...

  10. Comparative studies of method for determining total mercury in fish. Dithizone and flameless atomic absorption spectrophotometry techniques

    International Nuclear Information System (INIS)

    Protasowicki, M.; Ociepa, A.; Chodyniecki, A.

    1977-01-01

    Two methods for determining total mercury in fish were compared: the dithizone and flameless atomic absorption spectrophotometry techniques. The studies involved determination of recovery when 1μg of mercury as solutions of HgCl 2 or CH 3 HgC were added to each sample of herring flesh. Mean recoveries in the dithizone method were found to be 91.4+-7.47% and 90.25+-4.73% for the two solutions respectively, while the recoveries obtained with the flameless atomic absorption spectrophotometry were 95.00+-9.13% and 98.70+-7.14%, respectively. Both techniques were used to determine the mercury content in the same herring flesh sample. The first technique showed the content of 0.050+-0.018μg Hg g -1 while the result obtained with the other one was 0.062+-0.013μg Hg g -1 . The statistical treatment of the results obtained showed no difference between the two techniques, the significance level being α=0.05. Therefore, the results obtained with the dithizone method are comparable with those obtained with the flameless atomic absorption spectrophotometry for mercury contents of the magnitude order of 0.050 ug.g -1 . (author)

  11. First Measurements of Ambient Total Gaseous Mercury (TGM at the EvK2CNR Pyramid Observatory in Nepal

    Directory of Open Access Journals (Sweden)

    Gratz L. E.

    2013-04-01

    Full Text Available As part of the Global Mercury Observation System (GMOS project, a global-scale network of ground-based atmospheric monitoring sites is being developed with the objective of expanding the global coverage of atmospheric mercury (Hg measurements and improving our understanding of global atmospheric Hg transport. An important addition to the GMOS monitorng network has been the high altitude EvK2CNR Pyramid Observatory, located at an elevation of 5,050 meters a.s.l. in the eastern Himalaya Mountains of Nepal. Monitoring of total gaseous mercury (TGM using the Tekran 2537A Mercury Vapor Analyzer began at the EvK2CNR Pyramid Observatory in November 2011. From 17 November 2011 to 23 April 2012, the mean concentration of TGM at the Pyramid was 1.2 ng m−3. A range of concentrations from 0.7 to 2.6 ng m−3 has been observed. These are the first reported measurements of atmospheric Hg in Nepal, and currently this is the highest altitude monitoring station for atmospheric Hg in the world. It is anticipated that these high quality measurements, in combination with the other continuous atmospheric measurments being collected at the Pyramid station, will help to further our understanding of Hg concentrations in the free troposphere and the transport of atmospheric Hg on the global scale.

  12. EVALUATION OF TOTAL MERCURY CONTENT IN MUSCLE TISSUE OF MARINE FISH AND ANIMALS

    Directory of Open Access Journals (Sweden)

    Daniel Bajčan

    2013-02-01

    Full Text Available Nowdays, a degree of contamination by heavy metals can be observed in the environment. Heavy metals have serious effects on all living organisms because they can accumulate in lethal or sublethal concentrations in the various parts of food chain and so they can cause different health problems like cardiovascular and cancer diseases. Marine fish and animals are one of the bigges source of mercury in human food. Therefore this work is focused to the rate of mercury content in muscle tisuues of marine fish and animals. We analyzed mainly frozen or otherwise preserved marine fish and animals that were purchased in retail network in Slovakia. Mercury content in samples was analyzed by cold vapor AAS with mercury analyser AMA254. The contents of mercury in analysed samples were in the interval 0.0057 – 0,697 mg.kg-1. Our results shows, that no analyzed samples of marine fish and animals had over-limit concetration of Hg, so they are safe for human nutrition.

  13. Determination of total mercury in fillets of sport fishes collected from Folsom Reservoir, California, 2006

    Science.gov (United States)

    May, Thomas W.; Brumbaugh, William G.

    2007-01-01

    This report presents the results of a study by the U.S. Geological Survey, done in cooperation with the U.S. Bureau of Reclamation, to determine mercury concentrations in selected sport fishes from Folsom Reservoir in California. Fillets were collected from each fish sample, and after homogenization and lyophilization of fish fillets, mercury concentrations were determined with a direct mercury analyzer utilizing the process of thermal combustion-gold amalgamation atomic absorption spectroscopy. Mercury concentrations in fillets ranged from 0.031 to 0.20 micrograms per gram wet weight in rainbow trout (Oncorhynchus mykiss) samples and 0.071 to 0.16 micrograms per gram wet weight in bluegill (Lepomis macrochirus) samples. Mercury concentration was 0.98 microgram per gram wet weight in a single spotted bass (Micropterus punctulatus) sample, which was the only one in the sample set which exceeded the U.S. Environmental Protection Agency's fish consumption advisory of 0.30 microgram per gram wet weight.

  14. Determination of total mercury and methylmercury in human head hair by radiochemical methods of analysis

    International Nuclear Information System (INIS)

    Vasconcellos, M.B.A.; Saiki, M.; Paletti, G.; Pinheiro, R.M.M.; Baruzzi, R.G.; Spindel, R.

    1992-01-01

    Efforts were carried out in order to detect population groups in Brazil that could be at risk with respect to mercury contamination, mainly by ingestion of contaminated fish. Two regions were identified. The first was near Billings Dam which is located in one of the most heavily industrialized parts of the country. It is suspected that the water is polluted by chlor-alkali and other industrial pollutants. People living near this dam frequently consume fish caught around or near the dam. The second region is Xingu Park, located in the Amazonic region where several Indian tribes live and where the gold exploration activities have caused much concern due to the use of mercury in the ore processing. Tons of mercury are thrown in the rivers of the region annually. Both of these groups and a control group were used in this study. It was concluded that the population near Billings Dam had normal levels of mercury. However, the Indians from Xingu Park had very high levels of mercury in their Hair. It was determined that this group deserved further study. 7 refs, 2 tabs

  15. Dietary exposure of Hong Kong secondary school students to total mercury and methylmercury from fish intake.

    Science.gov (United States)

    Tang, Anna Shiu Ping; Kwong, Ka Ping; Chung, Stephen Wai Cheung; Ho, Yuk Yin; Xiao, Ying

    2009-01-01

    Fish is the main source of dietary exposure to methylmercury (MeHg), which is a public health concern owing to its potential neurotoxicity. To evaluate the public health risk, this study estimated the total mercury (tHg) and MeHg exposure from fish intake in Hong Kong secondary school students. Median tHg and MeHg concentrations of 280 samples purchased from different commercial outlets (covering 89 species of whole fish and three types of canned tuna), together with the local food consumption data of secondary school students obtained by semi-quantitative food frequency questionnaire in 2000, were used to estimate dietary exposure from fish intake for the average and high consumer (95th percentile exposure). For tHg, the median concentration was 63 µg kg(-1) (range 3-1370 µg kg(-1)) and estimated exposures ranged 0.5-0.6 µg kg(-1) body weight (bw) week(-1) for an average consumer and 1.6-1.9 µg kg(-1) bw week(-1) for a high consumer. For MeHg, median concentration was 48 µg kg(-1) (range 3-1010 µg kg(-1)) and estimated dietary exposures were 0.4-0.5 µg kg(-1) bw week(-1) for an average consumer and 1.2-1.4 µg kg(-1) bw week(-1) for a high consumer. These values are below the respective provisional tolerable weekly intake (PTWI) established by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA). The health risk is greater for high consumers since MeHg exposures may approach or exceed the PTWI when other dietary sources are taken into account.

  16. Open focused microwave-assisted sample preparation for rapid total and mercury species determination in environmental solid samples

    OpenAIRE

    Tseng, C. M.; Garraud, H.; Amouroux, D.; Donard, O. F. X.; de Diego, A.

    1998-01-01

    This paper describes rapid, simple microwave-assisted leaching/ digestion procedures for total and mercury species determination in sediment samples and biomaterials. An open focused microwave system allowed the sample preparation time to be dramatically reduced to only 24 min when a power of 40-80 W was applied. Quantitative leaching of methylmercury from sediments by HNO3 solution and complete dissolution of biomaterials by an alkaline solution, such as 25% TMAH solution, were obtained. Met...

  17. Total mercury levels in hair, toenail, and urine among women free from occupational exposure and their relations to renal tubular function

    International Nuclear Information System (INIS)

    Ohno, Tomoko; Sakamoto, Mineshi; Kurosawa, Tomoko; Dakeishi, Miwako; Iwata, Toyoto; Murata, Katsuyuki

    2007-01-01

    To investigate the relations among total mercury levels in hair, toenail, and urine, together with potential effects of methylmercury intake on renal tubular function, we determined their levels, and urinary N-acetyl-β-d-glucosaminidase activity (NAG) and α 1 -microglobulin (AMG) in 59 women free from occupational exposures, and estimated daily mercury intakes from fish and other seafood using a food frequency questionnaire. Mercury levels (mean+/-SD) in the women were 1.51+/-0.91μg/g in hair, 0.59+/-0.32μg/g in toenail, and 0.86+/-0.66μg/g creatinine in urine; and, there were positive correlations among them (P<0.001). The daily mercury intake of 9.15+/-7.84μg/day was significantly correlated with total mercury levels in hair, toenail, and urine (r=0.551, 0.537, and 0.604, P<0.001). Among the women, the NAG and AMG were positively correlated with both the daily mercury intake and mercury levels in hair, toenail, and urine (P<0.01); and, these relations were almost similar when using multiple regression analysis to adjust for possible confounders such as urinary cadmium (0.47+/-0.28μg/g creatinine) and smoking status. In conclusion, mercury resulting from fish consumption can explain total mercury levels in hair, toenail, and urine to some degree (about 30%), partly through the degradation into the inorganic form, and it may confound the renal tubular effect of other nephrotoxic agents. Also, the following equation may be applicable to the population neither with dental amalgam fillings nor with occupational exposures: [hair mercury (μg/g)]=2.44x[toenail mercury (μg/g)

  18. Total and methyl mercury concentrations in sediment and water of a constructed wetland in the Athabasca Oil Sands Region

    International Nuclear Information System (INIS)

    Oswald, Claire J.; Carey, Sean K.

    2016-01-01

    In the Athabasca Oil Sands Region in northeastern Alberta, Canada, oil sands operators are testing the feasibility of peatland construction on the post-mining landscape. In 2009, Syncrude Canada Ltd. began construction of the 52 ha Sandhill Fen pilot watershed, including a 15 ha, hydrologically managed fen peatland built on sand-capped soft oil sands tailings. An integral component of fen reclamation is post-construction monitoring of water quality, including salinity, fluvial carbon, and priority pollutant elements. In this study, the effects of fen reclamation and elevated sulfate levels on mercury (Hg) fate and transport in the constructed system were assessed. Total mercury (THg) and methylmercury (MeHg) concentrations in the fen sediment were lower than in two nearby natural fens, which may be due to the higher mineral content of the Sandhill Fen peat mix and/or a loss of Hg through evasion during the peat harvesting, stockpiling and placement processes. Porewater MeHg concentrations in the Sandhill Fen typically did not exceed 1.0 ng L −1 . The low MeHg concentrations may be a result of elevated porewater sulfate concentrations (mean 346 mg L −1 ) and an increase in sulphide concentrations with depth in the peat, which are known to suppress MeHg production. Total Hg and MeHg concentrations increased during a controlled mid-summer flooding event where the water table rose above the ground surface in most of the fen. The Hg dynamics during this event showed that hydrologic fluctuations in this system exacerbate the release of THg and MeHg downstream. In addition, the elevated SO 4 2− concentrations in the peat porewaters may become a problem with respect to downstream MeHg production once the fen is hydrologically connected to a larger wetland network that is currently being constructed. - Highlights: • A constructed fen peatland in the Athabasca Oil Sands Region was studied. • Total and methyl mercury concentrations in fen sediment and waters

  19. Determination of mercury in seawater by total reflection x-ray fluorescence spectrometry after an electrochemical preconcentration method

    International Nuclear Information System (INIS)

    Ritschel, A.; Chinea Cano, E.; Wobrauschek, P.; Kuntner, C.; Durakbasa, M.N.

    2000-01-01

    A new combined method of electrodeposition of trace elements on metallic plates with subsequent total-reflection x-ray fluorescence spectrometry (TXRF) is proposed for the determination of trace metals in natural waters. The elements of interest are electroplated on highly polished niobium discs which are used as sample carriers for the TXRF measurement. The electrochemical preconcentration is performed in a flow cell under a controlled working electrode potential. The preconcentration step involves only very little manipulation which minimizes the risk of contamination of the sample. The method was investigated by analyzing inorganic mercury in sea water. A detection limit of 7 ngl -1 could be achieved for mercury in a 40 ml sea water sample. (author)

  20. Geographic and temporal patterns of variation in total mercury concentrations in blood of harlequin ducks and blue mussels from Alaska.

    Science.gov (United States)

    Savoy, Lucas; Flint, Paul; Zwiefelhofer, Denny; Brant, Heather; Perkins, Christopher; Taylor, Robert; Lane, Oksana; Hall, Jeff; Evers, David; Schamber, Jason

    2017-04-15

    We compared total mercury (Hg) concentrations in whole blood of harlequin ducks (Histrionicus histrionicus) sampled within and among two geographically distinct locations and across three years in southwest Alaska. Blue mussels were collected to assess correlation between Hg concentrations in locally available forage and birds. Mercury concentrations in harlequin duck blood were significantly higher at Unalaska Island (0.31±0.19 mean±SD, μg/g blood) than Kodiak Island (0.04±0.02 mean±SD, μg/g blood). We found no evidence for annual variation in blood Hg concentration between years at Unalaska Island. However, blood Hg concentration did vary among specific sampling locations (i.e., bays) at Unalaska Island. Findings from this study demonstrate harlequin ducks are exposed to environmental sources of Hg, and whole blood Hg concentrations are associated with their local food source. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Total Blood Mercury Levels and Depression among Adults in the United States: National Health and Nutrition Examination Survey 2005–2008

    Science.gov (United States)

    Ng, Tsz Hin H.; Mossey, Jana M.; Lee, Brian K.

    2013-01-01

    Background Mercury is a neurotoxicant linked with psychiatric symptoms at high levels of exposure. However, it is unclear whether an association is present at the low exposure levels in the US adult population. Materials and Methods Cross-sectional associations of total blood mercury and depression were assessed in 6,911 adults age ≥20 in the National Health and Nutrition Examination Survey (NHANES), 2005–2008. The Patient Health Questionnaire-9 was used to assess depression (high likelihood of a depressive spectrum disorder diagnosis; score 5–27). Results Unadjusted survey weighted logistic regression suggested that higher total blood mercury was associated with lower odds of depression (Odds Ratio  = 0.49, 95% Confidence Interval: 0.36–0.65, comparing the highest and lowest mercury quintiles). This association largely disappeared after adjustment for sociodemographic variables (income-poverty ratio, education, marital status). However, in age-stratified analyses, this inverse relationship remained in older adults (age ≥40) even after adjustment for sociodemographic variables. Simulation analyses adjusting for expected confounding effects of fish intake suggested that the inverse relationship among older adults may be plausibly attributed to residual confounding (Odds Ratio  = 0.75, 95% Confidence Interval: 0.50–1.12, comparing the highest and lowest mercury quintiles). Conclusions Higher total blood mercury was not associated with increased odds of depression. The lower odds of depression in older adults with higher total blood mercury may be due to residual confounding. PMID:24244482

  2. Organic and total mercury determination in sediments by cold vapor atomic absorption spectrometry: methodology validation and uncertainty measurements

    Directory of Open Access Journals (Sweden)

    Robson L. Franklin

    2012-01-01

    Full Text Available The purpose of the present study was to validate a method for organic Hg determination in sediment. The procedure for organic Hg was adapted from literature, where the organomercurial compounds were extracted with dichloromethane in acid medium and subsequent destruction of organic compounds by bromine chloride. Total Hg was performed according to 3051A USEPA methodology. Mercury quantification for both methodologies was then performed by CVAAS. Methodology validation was verified by analyzing certified reference materials for total Hg and methylmercury. The uncertainties for both methodologies were calculated. The quantification limit of 3.3 µg kg-1 was found for organic Hg by CVAAS.

  3. A summary of total mercury concentrations in flora and fauna near common contaminant sources in the Gulf of Mexico.

    Science.gov (United States)

    Lewis, M; Chancy, C

    2008-02-01

    Total mercury concentrations are summarized for environmental media and biota collected from near-coastal areas, several impacted by contaminant sources common to the Gulf of Mexico. Water, sediment, fish, blue crabs, oysters, clams, mussels, periphyton and seagrasses were collected during 1993-2002 from targeted areas affected by point and non-point source contaminants. Mean concentrations in water and sediment were 0.02 (+/-1 standard deviation=0.06) microg l(-1) and 96.3 (230.8) ng g(-1) dry wt, respectively. Mean total mercury concentrations in fish, blue crabs, brackish clams and mussels were significantly greater than those in sediment, seagrass, colonized periphyton and oysters. Concentrations (ng g(-1) dry wt) averaged 23.1 (two seagrass species), 220.1 (oysters), 287.8 (colonized periphyton), 604.0 (four species of freshwater mussels), 772.4 (brackish clam), 857.9 (blue crabs) and 933.1 (nine fish species). Spatial, intraspecific and interspecific variability in results limited most generalizations concerning the relative mercury contributions of different stressor types. However, concentrations were significantly greater for some biota collected from areas receiving wastewater discharges and golf course runoff (fish), agricultural runoff (oysters) and urban stormwater runoff (colonized periphyton and sediment). Marine water quality criteria and proposed sediment quality guidelines were exceeded in 1-12% of total samples. At least one seafood consumption guideline, criteria or screening value were exceeded in edible tissues of blue crabs (6% total samples) and nine fish species (8-33% total samples) but all residues were less than the US Federal Drug Administration action limit of 1.0 ppm and the few reported toxic effect concentrations available for the targeted biota.

  4. Senegalese artisanal gold mining leads to elevated total mercury and methylmercury concentrations in soils, sediments, and rivers

    Directory of Open Access Journals (Sweden)

    Jacqueline R. Gerson

    2018-01-01

    Full Text Available The largest source of global mercury (Hg anthropogenic inputs to the environment is derived from artisanal and small-scale gold mining (ASGM activities in developing countries. While our understanding of global Hg emissions from ASGM is growing, there is limited empirical documentation about the levels of total mercury (THg and methylmercury (MeHg contamination near ASGM sites. We measured THg and MeHg concentrations in soil (n = 119, sediment (n = 22, and water (n = 25 from four active ASGM villages and one non-ASGM reference village in Senegal, West Africa. Nearly all samples had THg and MeHg concentrations that exceeded the reference village concentrations and USEPA regulatory standards. The highest median THg concentrations were found in huts where mercury-gold amalgams were burned (7.5 μg/g, while the highest median MeHg concentrations and percent Hg as MeHg were found in river sediments (4.2 ng/g, 0.41%. Median river water concentrations of THg and MeHg were also elevated compared to values at the reference site (22 ng THg/L, 0.037 ng MeHg/L in ASGM sites. This study provides direct evidence that Hg from ASGM is entering both the terrestrial and aquatic ecosystems where it is converted in soils, sediment, and water to the neurotoxic and bioavailable form of MeHg.

  5. Green Tea Increases the Concentration of Total Mercury in the Blood of Rats following an Oral Fish Tissue Bolus

    Directory of Open Access Journals (Sweden)

    Elsa M. Janle

    2015-01-01

    Full Text Available Fish has many health benefits but is also the most common source of methylmercury. The bioavailability of methylmercury in fish may be affected by other meal components. In this study, the effect of green tea on the bioavailability of methylmercury from an oral bolus of fish muscle tissue was studied in rats and compared to a water treated control group and a group treated with meso-2,3-dimercaptosuccinic acid (DMSA, a compound used medically to chelate mercury. Rats were given a single oral dose of fish tissue via gavage and one of the treatments. Rats were given access to food for 3 h at 12 h intervals. They were dosed with each of the treatments with each meal. Blood samples were collected for 95 hours. Green tea significantly increased the concentration of total mercury in blood relative to the control, whereas DMSA significantly decreased it. In addition, feeding caused a slight increase in blood mercury for several meals following the initial dose.

  6. Tracing mercury pathways in Augusta Bay (southern Italy) by total concentration and isotope determination

    International Nuclear Information System (INIS)

    Bonsignore, M.; Tamburrino, S.; Oliveri, E.; Marchetti, A.; Durante, C.; Berni, A.; Quinci, E.; Sprovieri, M.

    2015-01-01

    The mercury (Hg) pollution of sediments is the main carrier of Hg for the biota and, subsequently, for the local fish consumers in Augusta Bay area (SE Sicily, Italy), a coastal marine system affected by relevant sewage from an important chlor-alkali factory. This relationship was revealed by the determination of Mass Dependent (MDF) and Mass Independent Fractionation (MIF) of Hg isotopes in sediment, fish and human hair samples. Sediments showed MDF but no MIF, while fish showed MIF, possibly due to photochemical reduction in the water column and depending on the feeding habitat of the species. Benthic and demersal fish exhibited MDF similar to that of sediments in which anthropogenic Hg was deposited, while pelagic organisms evidenced higher MDF and MIF due to photoreduction. Human hair showed high values of δ 202 Hg (offset of +2.2‰ with respect to the consumed fish) and Δ 199 Hg, both associated to fish consumption. - Highlights: • We report the Hg isotope ratios of sediments, fish and human hair in Augusta Bay. • Hg isotopes show mercury transfers from sediments to benthic and demersal fish. • MIF in fish appears to be driven by effect of photoreduction. • MIF in human hair is inherited by fish consumption. - The mercury (Hg) isotope composition of sediments, fish muscles and human hair has been investigated from the highly polluted Augusta Bay (SE Sicily, Italy)

  7. Got Mercury?

    Science.gov (United States)

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

    2009-01-01

    airborne mercury vapor concentrations greater than 0.1 mg/cu m in the total spacecraft atmosphere for exposures lasting 30 days or less or 0.01 mg/cu m mercury vapor for exposures lasting more than 30 days. We also encourage the use of alternative devices that do not contain mercury.

  8. Spatial distribution and trends of total mercury in waters of the Great Lakes and connecting channels using an improved sampling technique

    International Nuclear Information System (INIS)

    Dove, A.; Hill, B.; Klawunn, P.; Waltho, J.; Backus, S.; McCrea, R.C.

    2012-01-01

    Environment Canada recently developed a clean method suitable for sampling trace levels of metals in surface waters. The results of sampling for total mercury in the Laurentian Great Lakes between 2003 and 2009 give a unique basin-wide perspective of concentrations of this important contaminant and represent improved knowledge of mercury in the region. Results indicate that concentrations of total mercury in the offshore regions of the lakes were within a relatively narrow range from about 0.3 to 0.8 ng/L. The highest concentrations were observed in the western basin of Lake Erie and concentrations then declined towards the east. Compared to the offshore, higher levels were observed at some nearshore locations, particularly in lakes Erie and Ontario. The longer-term temporal record of mercury in Niagara River suspended sediments indicates an approximate 30% decrease in equivalent water concentrations since 1986. - Highlights: ► Basin-wide concentrations of total mercury in Great Lakes surface waters are provided for the first time. ► A clean sampling method is described, stressing isolation of the sample from extraneous sources of contamination. ► Sub-ng/L concentrations of total mercury are observed in most Great Lakes offshore areas. ► Concentrations in the western basin of Lake Erie are consistently the highest observed in the basin. ► The longer-term record of mercury in Niagara River suspended sediments indicates an approximate 30% decrease since 1986. - A new, clean sampling method for metals is described and basin-wide measurements of total mercury are provided for Great Lakes surface waters for the first time.

  9. Iron telluride nanorods-based system for the detection of total mercury in blood

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Prathik; Lin, Zong-Hong [Department of Chemistry, National Taiwan University, 1, Section 4, Roosevelt Road, Taipei 106, Taiwan (China); Liang, Chi-Te [Department of Physics, National Taiwan University, 1, Section 4, Roosevelt Road, Taipei 106, Taiwan (China); Chang, Huan-Tsung, E-mail: changht@ntu.edu.tw [Department of Chemistry, National Taiwan University, 1, Section 4, Roosevelt Road, Taipei 106, Taiwan (China)

    2012-12-15

    Graphical abstract: Elucidation of the detection of mercury using iron telluride nanorods (FeTe NRs), and dose-response curve for varying concentrations of Hg{sup 2+}. Highlights: Black-Right-Pointing-Pointer Iron telluride nanorods (FeTe NRs) are prepared from tellurium nanowires (Te NWs). Black-Right-Pointing-Pointer Mercury telluride nanorods (HgTe NRs) form by cation exchange reaction of FeTe NRs. Black-Right-Pointing-Pointer Fe{sup 2+} ions released catalyze the oxidation of ABTS by H{sub 2}O{sub 2}. Black-Right-Pointing-Pointer Mercury is effectively determined in blood with an LOD of 1.31 nM at S/N ratio 3. - Abstract: We have developed a simple, colorimetric iron telluride (FeTe) nanorods (NRs) based system for the detection of mercury, mainly based on the cation exchange reaction between FeTe NRs and Hg{sup 2+}. FeTe NRs (length, 105 {+-} 21 nm) react with Hg{sup 2+} to form HgTe NRs (length, 112 {+-} 26 nm) and consequently release Fe{sup 2+} ions that catalyzes the oxidation between a peroxidase substrate 2,2 Prime -azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) diammonium salt (ABTS) and H{sub 2}O{sub 2}. The concentration of Fe{sup 2+} and thereby Hg{sup 2+} can be determined by measuring the absorbance of the ABTS oxidized product at 418 nm. This approach allows the detection of Hg{sup 2+}, with a limit of detection of 1.31 nM at a signal-to-noise ratio 3 and a linear range 5-100 nM (R{sup 2} = 0.99). The low-cost, simple, sensitive, and reproducible assay has been validated for the detection of Hg{sup 2+} in a blood sample (SRM 955c), with the result being in good agreement with that provided by National Institute of Standards and Technology.

  10. Distribution of total and methylmercury in different ecosystem compartments in the Everglades: Implications for mercury bioaccumulation

    Energy Technology Data Exchange (ETDEWEB)

    Liu Guangliang [Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199 (United States); Southeast Environmental Research Center, Florida International University, Miami, FL 33199 (United States); Cai Yong [Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, FL 33199 (United States); Southeast Environmental Research Center, Florida International University, Miami, FL 33199 (United States)], E-mail: cai@fiu.edu; Philippi, Thomas [Department of Biological Sciences, Florida International University, Miami, FL 33199 (United States); Kalla, Peter; Scheidt, Daniel [US Environmental Protection Agency, Region 4, Science and Ecosystem Support Division, Athens, GA 30605 (United States); Richards, Jennifer [Department of Biological Sciences, Florida International University, Miami, FL 33199 (United States); Scinto, Leonard [Southeast Environmental Research Center, Florida International University, Miami, FL 33199 (United States); Appleby, Charlie [US Environmental Protection Agency, Region 4, Science and Ecosystem Support Division, Athens, GA 30605 (United States)

    2008-05-15

    We analyzed Hg species distribution patterns among ecosystem compartments in the Everglades at the landscape level in order to explore the implications of Hg distribution for Hg bioaccumulation and to investigate major biogeochemical processes that are pertinent to the observed Hg distribution patterns. At an Everglade-wide scale, THg concentrations were significantly increased in the following order: periphyton < flocculent material (floc) < soil, while relatively high MeHg concentrations were observed in floc and periphyton. Differences in the methylation potential, THg concentration, and MeHg retention capacity could explain the relatively high MeHg concentrations in floc and periphyton. The MeHg/THg ratio was higher for water than for soil, floc, or periphyton probably due to high dissolved organic carbon (DOC) concentrations present in the Everglades. Mosquitofish THg positively correlated with periphyton MeHg and DOC-normalized water MeHg. The relative THg and MeHg distribution patterns among ecosystem compartments favor Hg bioaccumulation in the Everglades. - Mercury bioaccumulation in Florida Everglades is related to the distribution patterns of mercury species among ecosystem compartments.

  11. Distribution of total and methylmercury in different ecosystem compartments in the Everglades: Implications for mercury bioaccumulation

    International Nuclear Information System (INIS)

    Liu Guangliang; Cai Yong; Philippi, Thomas; Kalla, Peter; Scheidt, Daniel; Richards, Jennifer; Scinto, Leonard; Appleby, Charlie

    2008-01-01

    We analyzed Hg species distribution patterns among ecosystem compartments in the Everglades at the landscape level in order to explore the implications of Hg distribution for Hg bioaccumulation and to investigate major biogeochemical processes that are pertinent to the observed Hg distribution patterns. At an Everglade-wide scale, THg concentrations were significantly increased in the following order: periphyton < flocculent material (floc) < soil, while relatively high MeHg concentrations were observed in floc and periphyton. Differences in the methylation potential, THg concentration, and MeHg retention capacity could explain the relatively high MeHg concentrations in floc and periphyton. The MeHg/THg ratio was higher for water than for soil, floc, or periphyton probably due to high dissolved organic carbon (DOC) concentrations present in the Everglades. Mosquitofish THg positively correlated with periphyton MeHg and DOC-normalized water MeHg. The relative THg and MeHg distribution patterns among ecosystem compartments favor Hg bioaccumulation in the Everglades. - Mercury bioaccumulation in Florida Everglades is related to the distribution patterns of mercury species among ecosystem compartments

  12. Tidally driven export of dissolved organic carbon, total mercury, and methylmercury from a mangrove-dominated estuary

    Science.gov (United States)

    Bergamaschi, B.A.; Krabbenhoft, D.P.; Aiken, G.R.; Patino, E.; Rumbold, D.G.; Orem, W.H.

    2012-01-01

    The flux of dissolved organic carbon (DOC) from mangrove swamps accounts for 10% of the global terrestrial flux of DOC to coastal oceans. Recent findings of high concentrations of mercury (Hg) and methylmercury (MeHg) in mangroves, in conjunction with the common co-occurrence of DOC and Hg species, have raised concerns that mercury fluxes may also be large. We used a novel approach to estimate export of DOC, Hg, and MeHg to coastal waters from a mangrove-dominated estuary in Everglades National Park (Florida, USA). Using in situ measurements of fluorescent dissolved organic matter as a proxy for DOC, filtered total Hg, and filtered MeHg, we estimated the DOC yield to be 180 (??12.6) g C m -2 yr -1, which is in the range of previously reported values. Although Hg and MeHg yields from tidal mangrove swamps have not been previously measured, our estimated yields of Hg species (28 ?? 4.5 ??g total Hg m -2 yr -1 and 3.1 ?? 0.4 ??g methyl Hg m -2 yr -1) were five times greater than is typically reported for terrestrial wetlands. These results indicate that in addition to the well documented contributions of DOC, tidally driven export from mangroves represents a significant potential source of Hg and MeHg to nearby coastal waters. ?? 2011 American Chemical Society.

  13. Comparative analysis of total mercury concentrations in anadromous and non-anadromous Arctic charr (Salvelinus alpinus) from eastern Canada

    International Nuclear Information System (INIS)

    Velden, S. van der; Evans, M.S.; Dempson, J.B.; Muir, D.C.G.; Power, M.

    2013-01-01

    Previous research has documented that total mercury concentrations ([THg]) are lower in anadromous Arctic charr than in non-anadromous conspecifics, but the two life-history forms have rarely been studied together. Here, data from nine pairs of closely-located anadromous and non-anadromous Arctic charr populations were used to explore the impact of biological and life-history factors on individual [THg] across a range of latitudes (49–81° N) in eastern Canada. Unadjusted mean [THg] ranged from 20 to 114 ng/g wet weight (ww) in anadromous populations, and was significantly higher in non-anadromous populations, ranging from 111 to 227 ng/g ww. Within-population variations in [THg] were best explained by fish age, and were often positively related to fork-length and δ 15 N-inferred trophic level. Differences in [THg] were not related to differences in length-at-age (i.e., average somatic growth rate) among populations of either life-history type. Mercury concentrations were not related to site latitude in either the anadromous or non-anadromous fish. We conclude that the difference in Arctic charr [THg] with life-history type could not be explained by differences in fish age, fork-length, trophic position, or length-at-age, and discuss possible factors contributing to low mercury concentrations in anadromous, relative to freshwater, fish. - Highlights: ► Total mercury concentrations ([THg]) were measured in 9 co-located anadromous and non-anadromous Arctic charr populations. ► Mean [THg] in non-anadromous populations exceeded mean [THg] in spatially paired anadromous populations. ► Among-individual variation in [THg] was best explained by fish age. ► The lower [THg] in anadromous fish could not be explained by differences in age, fork-length, trophic level, or growth rate. ► Variations in Arctic charr [THg] were independent of latitude (49–81° N) in eastern Canada

  14. Distribution of total mercury and methylmercury around the small-scale gold mining area along the Cikaniki River, Bogor, Indonesia.

    Science.gov (United States)

    Tomiyasu, Takashi; Kodamatani, Hitoshi; Hamada, Yuriko Kono; Matsuyama, Akito; Imura, Ryusuke; Taniguchi, Yoko; Hidayati, Nuril; Rahajoe, Joeni Setijo

    2017-01-01

    This study investigates the distribution of total mercury (T-Hg) and methylmercury (MeHg) in the soil and water around the artisanal and small-scale gold mining (ASGM) area along the Cikaniki River, West Java, Indonesia. The concentration of T-Hg and MeHg in the forest soil ranged from 0.07 to 16.7 mg kg -1 and from <0.07 to 2.0 μg kg -1 , respectively, whereas it ranged from 0.40 to 24.9 mg kg -1 and from <0.07 to 56.3 μg kg -1 , respectively, in the paddy field soil. In the vertical variation of the T-Hg of forest soil, the highest values were observed at the soil surface, and these values were found to decrease with increasing depth. A similar variation was observed for MeHg and total organic carbon content (TOC), and a linear relationship was observed between them. Mercury deposited on the soil surface can be trapped and retained by organic matter and subjected to methylation. The slope of the line obtained for the T-Hg vs. TOC plot became larger near the ASGM villages, implying a higher rate of mercury deposition in these areas. In contrast, the plots of MeHg vs. TOC fell along the same trend line regardless of the distance from the ASGM village. Organic carbon content may be a predominant factor in controlling MeHg formation in forest soils. The T-Hg concentration in the river water ranged from 0.40 to 9.6 μg L -1 . River water used for irrigation can prove to be a source of mercury for the paddy fields. The concentrations of Hg 0 and Hg 2+ in river water showed similar variations as that observed for the T-Hg concentration. The highest Hg 0 concentration of 3.2 μg L -1 can be attributed to the waste inflow from work sites. The presence of Hg 0 in river water can become a source of mercury present in the atmosphere along the river. MeHg concentration in the river water was found to be 0.004-0.14% of T-Hg concentration, which was considerably lower than the concentrations of other Hg species. However, MeHg comprised approximately 0.2% of the T

  15. Seasonal and diel patterns of total gaseous mercury concentration in the atmosphere of the Central Valley of Costa Rica

    International Nuclear Information System (INIS)

    Castillo, Aylin; Valdes, Juan; Sibaja, Jose; Vega, Ilena; Alfaro, Rosa; Morales, Jose; Esquivel, Germain; Barrantes, Elisa; Black, Paleah; Lean, David

    2011-01-01

    Research highlights: → Elevated seasonal and daily patterns of total gaseous mercury (TGM) were observed in the Central Valley of Costa Rica 27 km south-east of the Poas volcano. → With the onset of the wet season TGM in late April, values increased from typical values near 10 to 905 ng m -3 . → During the day, TGM values increased until midday along with temperature and radiation but relative humidity showed a reciprocal pattern. → We conclude that elemental mercury from the volcano may react with atmospheric oxidants especially during the dry season and the mercury would be deposited to the ground. → With the onset of heavy rains, mercury in the soil is reduced and re-volatilized resulting in the high levels in atmospheric air at the end of April. - Abstract: Monitoring of Hg in the atmosphere near volcanoes is limited with no previous data for Costa Rica. Seasonal and daily patterns of total gaseous mercury (TGM) were observed at the main sampling location at the Universidad Nacional, Heredia, Costa Rica. The area (lat. 10.000230 long. -84.109499) is located in the Central Valley of Costa Rica and is 27 km SE of the Poas volcano (lat. 10.199486 long. -84.231388). Measurements were made from May 2008 to May 2009 at this location with some additional values obtained at other sites near the Poas volcano including San Luis and Grecia as well as near, Turrialba and Irazu volcanoes. Total gaseous Hg was determined in samples collected at a height of 2 m using the Tekran 2537A (Tekran Inc.) gas-phase Hg vapor analyzer. Meteorological data (temperature, relative humidity, wind speed, wind direction, radiation and precipitation) were obtained from the airport weather station located at Alajuela. Monthly precipitation is typically 85 mm during the dry season (December to April) with winds from the west. The wet season begins in late April and continues to December with monthly rainfall of 328 mm and winds from the NE. The annual mean temperature is 20 deg. C

  16. Seasonal and diel patterns of total gaseous mercury concentration in the atmosphere of the Central Valley of Costa Rica

    Energy Technology Data Exchange (ETDEWEB)

    Castillo, Aylin; Valdes, Juan; Sibaja, Jose; Vega, Ilena; Alfaro, Rosa; Morales, Jose; Esquivel, Germain; Barrantes, Elisa [Laboratory for Atmospheric Chemistry, LAQAT-UNA, Universidad Nacional, P.O. Box 86-3000, Heredia (Costa Rica); Black, Paleah [Department of Biology, University of Ottawa, P.O. Box 450 Station A, Ottawa, Ontario, K1N 6N5 (Canada); Lean, David, E-mail: drslean@gmail.com [P.O. Box 309, Apsley, Ontario, K0L 1A0 (Canada)

    2011-02-15

    Research highlights: {yields} Elevated seasonal and daily patterns of total gaseous mercury (TGM) were observed in the Central Valley of Costa Rica 27 km south-east of the Poas volcano. {yields} With the onset of the wet season TGM in late April, values increased from typical values near 10 to 905 ng m{sup -3}. {yields} During the day, TGM values increased until midday along with temperature and radiation but relative humidity showed a reciprocal pattern. {yields} We conclude that elemental mercury from the volcano may react with atmospheric oxidants especially during the dry season and the mercury would be deposited to the ground. {yields} With the onset of heavy rains, mercury in the soil is reduced and re-volatilized resulting in the high levels in atmospheric air at the end of April. - Abstract: Monitoring of Hg in the atmosphere near volcanoes is limited with no previous data for Costa Rica. Seasonal and daily patterns of total gaseous mercury (TGM) were observed at the main sampling location at the Universidad Nacional, Heredia, Costa Rica. The area (lat. 10.000230 long. -84.109499) is located in the Central Valley of Costa Rica and is 27 km SE of the Poas volcano (lat. 10.199486 long. -84.231388). Measurements were made from May 2008 to May 2009 at this location with some additional values obtained at other sites near the Poas volcano including San Luis and Grecia as well as near, Turrialba and Irazu volcanoes. Total gaseous Hg was determined in samples collected at a height of 2 m using the Tekran 2537A (Tekran Inc.) gas-phase Hg vapor analyzer. Meteorological data (temperature, relative humidity, wind speed, wind direction, radiation and precipitation) were obtained from the airport weather station located at Alajuela. Monthly precipitation is typically 85 mm during the dry season (December to April) with winds from the west. The wet season begins in late April and continues to December with monthly rainfall of 328 mm and winds from the NE. The annual mean

  17. Ecotoxicoparasitology of the gastrointestinal tracts of pinnipeds: the effect of parasites on the potential bioavailability of total mercury (THg).

    Science.gov (United States)

    McGrew, Ashley K; O'Hara, Todd M; Stricker, Craig A; Salman, Mo D; Van Bonn, William; Gulland, Frances M D; Whiting, Alex; Ballweber, Lora R

    2018-08-01

    Acanthocephalans, cestodes, and some species of nematodes acquire nutrients from the lumen contents in the gastrointestinal (GI) tract of their definitive host. These parasites are exposed to toxicants, such as mercury (Hg), through passive or active feeding mechanisms; therefore, the focus of this study was to determine if there is an effect of parasites on the dietary availability of total mercury (THg) within piscivorous pinniped hosts. THg concentrations ([THg]) in selected host tissues, parasites, and GI lumen contents from 22 California sea lions (Zalophus californianus), 15 ringed seals (Phoca hispida), and 4 spotted seals (Phoca largha) were determined. Among all pinnipeds, [THg] in acanthocephalans of the large intestine were significantly higher than concentrations in other samples (host lumen contents, other parasites and host intestinal wall), irrespective of location within the host GI tract. δ 15 N values of parasites depended both on parasite group and location within the GI tract. δ 15 N values were consistently higher in parasites inhabiting the large intestine, compared to elsewhere in the GI tract, for both sea lions and seals. δ 13 C values in parasites did not differ significantly from host GI tissues. Based on both [THg] and stable isotope values, parasites are likely affecting the Hg bioavailability within the GI lumen contents and host tissues, and toxicant-parasite interactions appear to depend on both parasitic taxon as well as their location within the host intestine. Copyright © 2018. Published by Elsevier B.V.

  18. Total mercury and methylmercury concentrations over a gradient of contamination in earthworms living in rice paddy soil.

    Science.gov (United States)

    Abeysinghe, Kasun S; Yang, Xiao-Dong; Goodale, Eben; Anderson, Christopher W N; Bishop, Kevin; Cao, Axiang; Feng, Xinbin; Liu, Shengjie; Mammides, Christos; Meng, Bo; Quan, Rui-Chang; Sun, Jing; Qiu, Guangle

    2017-05-01

    Mercury (Hg) deposited from emissions or from local contamination, can have serious health effects on humans and wildlife. Traditionally, Hg has been seen as a threat to aquatic wildlife, because of its conversion in suboxic conditions into bioavailable methylmercury (MeHg), but it can also threaten contaminated terrestrial ecosystems. In Asia, rice paddies in particular may be sensitive ecosystems. Earthworms are soil-dwelling organisms that have been used as indicators of Hg bioavailability; however, the MeHg concentrations they accumulate in rice paddy environments are not well known. Earthworm and soil samples were collected from rice paddies at progressive distances from abandoned mercury mines in Guizhou, China, and at control sites without a history of Hg mining. Total Hg (THg) and MeHg concentrations declined in soil and earthworms as distance increased from the mines, but the percentage of THg that was MeHg, and the bioaccumulation factors in earthworms, increased over this gradient. This escalation in methylation and the incursion of MeHg into earthworms may be influenced by more acidic soil conditions and higher organic content further from the mines. In areas where the source of Hg is deposition, especially in water-logged and acidic rice paddy soil, earthworms may biomagnify MeHg more than was previously reported. It is emphasized that rice paddy environments affected by acidifying deposition may be widely dispersed throughout Asia. Environ Toxicol Chem 2017;36:1202-1210. © 2016 SETAC. © 2016 SETAC.

  19. Organic, inorganic and total mercury determination in fish by chemical vapor generation with collection on a gold gauze and electrothermal atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Duarte, Fabio Andrei; Bizzi, Cezar Augusto; Goldschmidt Antes, Fabiane; Dressler, Valderi Luiz; Flores, Erico Marlon de Moraes

    2009-01-01

    A method for organic, inorganic and total mercury determination in fish tissue has been developed using chemical vapor generation and collection of mercury vapor on a gold gauze inside a graphite tube and further atomization by electrothermal atomic absorption spectrometry. After drying and cryogenic grinding, potassium bromide and hydrochloric acid solution (1 mol L - 1 KBr in 6 mol L - 1 HCl) was added to the samples. After centrifugation, total mercury was determined in the supernatant. Organomercury compounds were selectively extracted from KBr solution using chloroform and the resultant solution was back extracted with 1% m/v L-cysteine. This solution was used for organic Hg determination. Inorganic Hg remaining in KBr solution was directly determined by chemical vapor generation electrothermal atomic absorption spectrometry. Mercury vapor generation from extracts was performed using 1 mol L - 1 HCl and 2.5% m/v NaBH 4 solutions and a batch chemical vapor generation system. Mercury vapor was collected on the gold gauze heated resistively at 80 deg. C and the atomization temperature was set at 650 deg. C. The selectivity of extraction was evaluated using liquid chromatography coupled to chemical vapor generation and determination by inductively coupled plasma mass spectrometry. The proposed method was applied for mercury analysis in shark, croaker and tuna fish tissues. Certified reference materials were used to check accuracy and the agreement was better than 95%. The characteristic mass was 60 pg and method limits of detection were 5, 1 and 1 ng g - 1 for organic, inorganic and total mercury, respectively. With the proposed method it was possible to analyze up to 2, 2 and 6 samples per hour for organic, inorganic and total Hg determination, respectively.

  20. Method Performance of Total Mercury (Hg) Testing in the Biological Samples by Using Cold Vapour Atomic Absorption Spectrophotometer (CV-AAS)

    International Nuclear Information System (INIS)

    Susanna TS; Samin

    2007-01-01

    Method performance (validation) of total mercury (Hg) testing in the biological samples by using cold vapour atomic absorption spectrophotometer (CV-AAS) has been done. The objective of this research is to know the method performance of CV-AAS as one of points for the accreditation testing of laboratory according IS0/IEC 17025-2005. The method performance covering limit of detection (LOD), accuracy, precision and bias. As a standard material used SRM Oyster Tissue 15660 from Winopal Forshung Germany, whereas the biological samples were human hair. In principle of mercury testing for solid samples using CV-AAS is dissolving this sample and standard with 10 mL HNO 3 supra pure into a closed quartz tube and heating at 150 °C for 4 hours. The concentration of mercury in each samples was determined at the condition of operation were stirring time (T 1 ) 70 seconds, delay time (T 2 ) 15 seconds, heating time (T 3 ) 13 seconds and cooling time (T 4 ) of 25 seconds. Mercury ion in samples are reduced with SnCl 2 10 % in H 2 SO 4 20 %, and then the vapour of mercury from reduction is passed in NaOH 20 % solution and aquatridest. The result of method performance were: limit of detection (LOD) = 0.085 ng, accuracy 99.70 %, precision (RSD) = 1.64 % and bias = 0.30 %. From the validation result showed that the content of mercury total was in the range of certified values. The total mercury content (Hg) in human hair were varied from 406.93 - 699.07 ppb. (author)

  1. Biological and life-history factors affecting total mercury concentrations in Arctic charr from Heintzelman Lake, Ellesmere Island, Nunavut

    International Nuclear Information System (INIS)

    Velden, Shannon van der; Reist, James D.; Babaluk, John A.; Power, Michael

    2012-01-01

    A snapshot sample of Arctic charr (Salvelinus alpinus) from Heintzelman Lake (81°42′N, 66°56′W), Ellesmere Island, Canada was used to elucidate the biological and life-history factors potentially influencing individual total mercury (THg) concentrations. Migratory history was significant, with anadromous fish having a lower mean THg concentration (64 μg/kg ww) than the non-anadromous Arctic charr (117 μg/kg ww). The increase in individual THg concentration with age was shown to be independent of length-at-age when large and small individuals within the same age groups were compared. Similarly, the diets of individual Arctic charr were comparable regardless of size, and there was no apparent ontogenetic shift in diet that could explain differences in length-at-age or THg concentration among fast- and slow-growing groups of fish (i.e., fish of the same age but differing sizes). Maturity state was also not related to THg concentration, but appears to be related to differences in length-at-age, with slow-growing fish allocating more energy to reproduction than fast-growing conspecifics. The differences in THg concentration among individual Arctic charr were best explained by fish age. We suggest that the increase in mercury concentration with age can be altered by a shift in diet (e.g., to piscivory) or habitat (e.g., anadromy), but is otherwise unaffected by changes in size or length-at-age. -- Highlights: ► Total mercury concentrations ([THg]) were measured in Arctic charr from a single lake in the Canadian high Arctic. ► Anadromous Arctic charr had a significantly lower mean [THg] (64 μg/kg ww) than the non-anadromous fish (117 μg/kg ww). ► Length-at-age (i.e., average somatic growth rate) was not related to mean [THg] when same-age groups were compared. ► Prey resource use, determined by δ 13 C and δ 15 N isotopes and gut contents, was similar among fast- and slow-growing fish. ► Maturity state was not related to [THg], but the slow

  2. Total and methyl mercury concentrations in sediment and water of a constructed wetland in the Athabasca Oil Sands Region.

    Science.gov (United States)

    Oswald, Claire J; Carey, Sean K

    2016-06-01

    In the Athabasca Oil Sands Region in northeastern Alberta, Canada, oil sands operators are testing the feasibility of peatland construction on the post-mining landscape. In 2009, Syncrude Canada Ltd. began construction of the 52 ha Sandhill Fen pilot watershed, including a 15 ha, hydrologically managed fen peatland built on sand-capped soft oil sands tailings. An integral component of fen reclamation is post-construction monitoring of water quality, including salinity, fluvial carbon, and priority pollutant elements. In this study, the effects of fen reclamation and elevated sulfate levels on mercury (Hg) fate and transport in the constructed system were assessed. Total mercury (THg) and methylmercury (MeHg) concentrations in the fen sediment were lower than in two nearby natural fens, which may be due to the higher mineral content of the Sandhill Fen peat mix and/or a loss of Hg through evasion during the peat harvesting, stockpiling and placement processes. Porewater MeHg concentrations in the Sandhill Fen typically did not exceed 1.0 ng L(-1). The low MeHg concentrations may be a result of elevated porewater sulfate concentrations (mean 346 mg L(-1)) and an increase in sulphide concentrations with depth in the peat, which are known to suppress MeHg production. Total Hg and MeHg concentrations increased during a controlled mid-summer flooding event where the water table rose above the ground surface in most of the fen. The Hg dynamics during this event showed that hydrologic fluctuations in this system exacerbate the release of THg and MeHg downstream. In addition, the elevated SO4(2-) concentrations in the peat porewaters may become a problem with respect to downstream MeHg production once the fen is hydrologically connected to a larger wetland network that is currently being constructed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Total particulate and reactive gaseous mercury in ambient air on the eastern slope of the Mt. Gongga area, China

    International Nuclear Information System (INIS)

    Fu Xuewu; Feng Xinbin; Zhu Wanze; Zheng Wei; Wang Shaofeng; Lu, Julia Y.

    2008-01-01

    Total particulate mercury (TPM) and reactive gaseous mercury (RGM) concentrations in ambient air on the eastern slope of the Mt. Gongga area, Sichuan Province, Southwestern China were monitored from 25 May, 2005 to 29 April, 2006. Simultaneously, Hg concentrations in rain samples were measured from January to December, 2006. The average TPM and RGM concentrations in the study site were 30.7 and 6.2 pg m -3 , which are comparable to values observed in remote areas in Northern America and Europe, but much lower than those reported in some urban areas in China. The mean seasonal RGM concentration was slightly higher in spring (8.0 pg m -3 ) while the minimum mean concentration was observed in winter (4.0 pg m -3 ). TPM concentrations ranged across two orders of magnitude from 5.2 to 135.7 pg m -3 and had a clear seasonal variation: winter (74.1 pg m -3 ), autumn (22.5 pg m -3 ), spring (15.3 pg m -3 ) and summer (10.8 pg m -3 ), listed in decreasing order. The annual wet deposition was 9.1 μg m -2 and wet deposition in the rainy season (May-October) represented over 80% of the annual total. The temporal distribution of TPM and RGM suggested distinguishable dispersion characteristics of these Hg species on a regional scale. Elevated TPM concentration in winter was probably due to regional and local enhanced coal burning and low wet deposition velocity. The RGM distribution pattern is closely related to daily variation in UV radiation observed during the winter sampling period indicating that photo-oxidation processes and diurnal changes in meteorology play an important role in RGM generation

  4. Total particulate and reactive gaseous mercury in ambient air on the eastern slope of the Mt. Gongga area, China

    Energy Technology Data Exchange (ETDEWEB)

    Fu, X.W.; Feng, X.B.; Zhu, W.Z.; Zheng, W.; Wang, S.F.; Lu, J.Y. [Chinese Academy of Sciences, Guiyang (China)

    2008-03-15

    Total particulate mercury (TPM) and reactive gaseous mercury (RGM) concentrations in ambient air on the eastern slope of the Mt. Gongga area, Sichuan Province, Southwestern China were monitored from 25 May, 2005 to 29 April, 2006. Simultaneously, Hg concentrations in rain samples were measured from January to December, 2006. The average TPM and RGM concentrations in the study site were 30.7 and 6.2 pg m{sup -3}, which are comparable to values observed in remote areas in Northern America and Europe, but much lower than those reported in some urban areas in China. The mean seasonal RGM concentration was slightly higher in spring (8.0 pg m{sup -3}) while the minimum mean concentration was observed in winter (4.0 pg m{sup -3}). TPM concentrations ranged across two orders of magnitude from 5.2 to 135.7 Pg m{sup -3} and had a clear seasonal variation: winter (74.1 pg m{sup -3}), autumn (22.5 Pg m{sup -3}), spring (15.3 Pg m{sup -3}) and summer (10.8 Pg m{sup -3}), listed in decreasing order. The annual wet deposition was 9.1 {mu} g m{sup -2} and wet deposition in the rainy season (May-October) represented over 80% of the annual total. The temporal distribution of TPM and RGM suggested distinguishable dispersion characteristics of these Hg species on a regional scale. Elevated TPM concentration in winter was probably due to regional and local enhanced coal burning and low wet deposition velocity. The RGM distribution pattern is closely related to daily variation in UV radiation observed during the winter sampling period indicating that photo-oxidation processes and diurnal changes in meteorology play an important role in RGM generation.

  5. Total particulate and reactive gaseous mercury in ambient air on the eastern slope of the Mt. Gongga area, China

    Energy Technology Data Exchange (ETDEWEB)

    Fu Xuewu [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China); Graduate University of the Chinese Academy Sciences, Beijing 100049 (China); Feng Xinbin [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China)], E-mail: fengxinbin@vip.skleg.cn; Zhu Wanze [Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041 (China); Zheng Wei; Wang Shaofeng [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China); Graduate University of the Chinese Academy Sciences, Beijing 100049 (China); Lu, Julia Y. [Department of Chemistry and Biology, Ryerson University, Toronto, Ont., M5B 2K3 (Canada)

    2008-03-15

    Total particulate mercury (TPM) and reactive gaseous mercury (RGM) concentrations in ambient air on the eastern slope of the Mt. Gongga area, Sichuan Province, Southwestern China were monitored from 25 May, 2005 to 29 April, 2006. Simultaneously, Hg concentrations in rain samples were measured from January to December, 2006. The average TPM and RGM concentrations in the study site were 30.7 and 6.2 pg m{sup -3}, which are comparable to values observed in remote areas in Northern America and Europe, but much lower than those reported in some urban areas in China. The mean seasonal RGM concentration was slightly higher in spring (8.0 pg m{sup -3}) while the minimum mean concentration was observed in winter (4.0 pg m{sup -3}). TPM concentrations ranged across two orders of magnitude from 5.2 to 135.7 pg m{sup -3} and had a clear seasonal variation: winter (74.1 pg m{sup -3}), autumn (22.5 pg m{sup -3}), spring (15.3 pg m{sup -3}) and summer (10.8 pg m{sup -3}), listed in decreasing order. The annual wet deposition was 9.1 {mu}g m{sup -2} and wet deposition in the rainy season (May-October) represented over 80% of the annual total. The temporal distribution of TPM and RGM suggested distinguishable dispersion characteristics of these Hg species on a regional scale. Elevated TPM concentration in winter was probably due to regional and local enhanced coal burning and low wet deposition velocity. The RGM distribution pattern is closely related to daily variation in UV radiation observed during the winter sampling period indicating that photo-oxidation processes and diurnal changes in meteorology play an important role in RGM generation.

  6. Radiochemical investigations on the decomposition of (mono)methylmercury by means of acid with regard to the determination of total mercury in fish

    International Nuclear Information System (INIS)

    Harms, U.

    1976-01-01

    Considerable amounts of mercury in fish muscle tissue are organically bound, i.e. appear as (mono)methylmercury-compounds. In order to make mercury of organic origin available for the determination of total mercury by the 'cold vapour atomic absorption method', a splitting of the carbon-mercury bond by means of suitable chemical treatment must be maintained beforehand. The main subject of this article are investigations with special regard to the behaviour of (mono)methylmercurychloride during different wet digestion methods. The procedures under study involve wet digestion under reflux with HNO 3 , with mixtures of HNO 3 and HClO 4 and HNO 3 and H 2 SO 4 , as well as wet digestion with HNO 3 in a closed system (pressure decomposition). The course of the decomposition of (mono)methylmercury dependent on time, temperature and concentration of reagents are discussed in detail. All experiments were controlled by measurement of the radioactivity of Hg-203 which had been added in the chemical form of CH 3 -Hg-Cl. From the analytical results obtained two methods of sample preparation have been derived that permit a reliable determination of total mercury in fish. (orig.) [de

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

    Science.gov (United States)

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

    2017-08-01

    Meat samples of 84 minke whales (Balaenoptera acutorostrata) mainly from the Barents Sea, collected between 1 May and 16 August 2011, were analyzed for total mercury, methylmercury, cadmium, lead, total arsenic, inorganic arsenic and selenium. The average total mercury concentration found was 0.15 ± 0.09 mg/kg, with a range from 0.05 to 0.49 mg/kg. The molar ratio of selenium to mercury varied between 1.0 and 10.3. Cadmium content ranged from 0.002 to 0.036 mg/kg, while the content of lead in whale meat ranged from whale samples exceeded established EU maximum levels for metals in fish muscle, but 4.8% and 6.8% of the samples exceeded Japanese maximum levels for total mercury and methylmercury, respectively, in whale meat. There was only minor variations in element concentrations between whales from different geographical areas, and cadmium was the only element were the concentration increased with increasing length.

  8. Study on total mercury and methylmercury levels in hair and tissues of typical human populations exposed to mercury in China by NAA and GC(EC)

    International Nuclear Information System (INIS)

    Chai Chifang; Qian Qinfang; Feng Weiyu; Sun Jianguo; Li Xinji; Lu Yilun; Zhang Xioumei; Zhang Shen

    1992-01-01

    Since the first Research Coordination Meeting in Vienna, 10-13 June 1991, China has been putting the research emphasis on two aspects for studying mercury exposure to the population. The first is a methodology for methylmercury analysis. The second is the collection and analysis of representative hair samples. The main activities during this study period are summarized in this paper. 8 tabs

  9. Rapid food decomposition by H2O2-H2SO4 for determination of total mercury by flow injection cold vapor atomic absorption spectrometry.

    Science.gov (United States)

    Zenebon, Odair; Sakuma, Alice M; Dovidauskas, Sergio; Okada, Isaura A; de, MaioFrancaD; Lichtig, Jaim

    2002-01-01

    A mixture of 50% H2O2-H2SO4 (3 + 1, v/v) was used for decomposition of food in open vessels at 80 degrees C. The treatment allowed rapid total mercury determination by flow injection cold vapor atomic absorption spectrometry. Cabbage, potatoes, peanuts paste, hazelnuts paste, oats, tomatoes and their derivatives, oysters, shrimps, prawns, shellfish, marine algae, and many kinds of fish were analyzed by the proposed methodology with a limit of quantitation of 0.86 +/- 0.08 microg/L mercury in the final solution. Reference materials tested also gave excellent recovery.

  10. Total mercury and methylmercury fluxes via emerging insects in recently flooded hydroelectric reservoirs and a natural lake

    International Nuclear Information System (INIS)

    Tremblay, Alain; Lucotte, Marc; Cloutier, Louise

    1998-01-01

    Total mercury (total Hg) concentrations in emerging aquatic insects ranged from 140 to 1500 ng g -1 dry wt. in two hydroelectric reservoirs of northern Quebec compared with 50-160 ng g -1 dry wt. in a natural lake. Methylmercury (MeHg) concentrations were somewhat lower, ranging from 35 to 800 ng Hg g -1 dry wt. in reservoirs and from 29 to 90 ng g -1 dry wt. in the natural lake. Contamination of insect taxa of reservoirs was on average 2-3 times higher than their counterparts in the natural lake. There was no difference between total Hg and MeHg concentrations of insects sampled from flooded forest soils and flooded peatland, although total Hg and MeHg concentrations differed between flooded peatland and flooded forest soils themselves. Insect biomasses were approx. two times higher in the reservoirs than in the natural lake (580-2200 mg m -2 year -1 dry wt., 950 mg m -2 year -1 dry wt., respectively); chironomids dominated in the reservoirs and trichopterans dominated in the natural lake. Similarly, total MeHg fluxes via emerging insects were approx. 2-4 times higher in reservoirs than that of the natural lake (55-224 ng MeHg m -2 year -1 dry wt., 74 ng MeHg m -2 year -1 dry wt., respectively). Our results show the importance of the insect community in the transfer of MeHg from flooded soils and flooded peatlands to fish, and that this pathway probably makes a significant contribution to the rapid rise of Hg levels in the fish community after flooding

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

    Science.gov (United States)

    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%.

  12. Method and apparatus for monitoring mercury emissions

    Science.gov (United States)

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

    1997-01-01

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

  13. Cooking process evaluation on micronutrient and total mercury content in fish species in Manaus, Brazil

    International Nuclear Information System (INIS)

    Farias, Luciana; Favaro, Deborah I.T.; Vaconcellos, Marina B.A.

    2007-01-01

    This study evaluated different cooking processes (roasted, cooked and fried) on micronutrient (Ca, Fe, K, Na, Se and Zn) and total Hg content in fish species most consumed by Manaus residents and surrounding communities. Twelve different fresh water fish species were purchased at the central receiving market (CEASA) in Manaus and prepared at the INPA Food and Nutrition Laboratory. In total 64 fish samples were analysed. Analytical determinations were performed by Neutron Activation Analysis Technique (NAA) for micronutrients and Atomic Absorption Spectrometry (CV AAS) for total Hg. All analytical methods were developed and validated for precision and accuracy by means of reference material analyses with certified values for the elements determined. The concentration variation of the analyzed elements was: Hg (2392 to 19 μ kg -1 ); K (19187 to 1185 mg kg -1 ); Ca (14590 to 994 mg kg -1 ); Na (18386 to 12850 mg kg -1 ); Fe (5580 to 4 mg kg -1 ); Se (5249 to 129 μg kg -1 ) and Zn (684 to 15 mg kg -1 ). The effect of the different cooking processes on the variation of micronutrient composition was quite significant. On the other hand Hg composition variation seems to be more related to fish species rather than the cooking process itself. As was expected, predatory species presented higher Hg and Se levels. (author)

  14. A new vapor generation system for mercury species based on the UV irradiation of mercaptoethanol used in the determination of total and methyl mercury in environmental and biological samples by atomic fluorescence spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Yanmin; Qiu, Jianhua; Yang, Limin [College of Chemistry and Chemical Engineering, Xiamen University, Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, Xiamen (China); Wang, Qiuquan [College of Chemistry and Chemical Engineering, Xiamen University, Department of Chemistry and the MOE Key Laboratory of Analytical Sciences, Xiamen (China); Xiamen University, State Key Laboratory of Marine Environmental Science, Xiamen (China)

    2007-06-15

    A new vapor generation system for mercury (Hg) species based on the irradiation of mercaptoethanol (ME) with UV was developed to provide an effective sample introduction unit for atomic fluorescence spectrometry (AFS). Preliminary investigations of the mechanism of this novel vapor generation system were based on GC-MS and FT-IR studies. Under optimum conditions, the limits of determination for inorganic divalence mercury and methyl mercury were 60 and 50 pg mL{sup -1}, respectively. Certified reference materials (BCR 463 tuna fish and BCR 580 estuarine sediment) were used to validate this new method, and the results agreed well with certified values. This new system provides an attractive alternative method of chemical vapor generation (CVG) of mercury species compared to other developed CVG systems (for example, the traditional KBH{sub 4}/NaOH-acid system). To our knowledge, this is the first systematic report on UV/ME-based Hg species vapor generation and the determination of total and methyl Hg in environmental and biological samples using UV/ME-AFS. (orig.)

  15. Species- and habitat-specific bioaccumulation of total mercury and methylmercury in the food web of a deep oligotrophic lake.

    Science.gov (United States)

    Arcagni, Marina; Juncos, Romina; Rizzo, Andrea; Pavlin, Majda; Fajon, Vesna; Arribére, María A; Horvat, Milena; Ribeiro Guevara, Sergio

    2018-01-15

    Niche segregation between introduced and native fish in Lake Nahuel Huapi, a deep oligotrophic lake in Northwest Patagonia (Argentina), occurs through the consumption of different prey. Therefore, in this work we analyzed total mercury [THg] and methylmercury [MeHg] concentrations in top predator fish and in their main prey to test whether their feeding habits influence [Hg]. Results indicate that [THg] and [MeHg] varied by foraging habitat and they increased with greater percentage of benthic diet and decreased with pelagic diet in Lake Nahuel Huapi. This is consistent with the fact that the native creole perch, a mostly benthivorous feeder, which shares the highest trophic level of the food web with introduced salmonids, had higher [THg] and [MeHg] than the more pelagic feeder rainbow trout and bentho-pelagic feeder brown trout. This differential THg and MeHg bioaccumulation observed in native and introduced fish provides evidence to the hypothesis that there are two main Hg transfer pathways from the base of the food web to top predators: a pelagic pathway where Hg is transferred from water, through plankton (with Hg in inorganic species mostly), forage fish to salmonids, and a benthic pathway, as Hg is transferred from the sediments (where Hg methylation occurs mostly), through crayfish (with higher [MeHg] than plankton), to native fish, leading to one fold higher [Hg]. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Determination of total mercury in fillets of sport fishes collected from Folsom and New Melones Reservoirs, California, 2004

    Science.gov (United States)

    May, Thomas W.; Brumbaugh, William G.

    2007-01-01

    This report presents the results of a study by the U.S. Geological Survey, done in cooperation with the U.S. Bureau of Reclamation, to determine mercury concentrations in selected sport fishes from Folsom and New Melones Reservoirs in California. Fillets were collected from each fish sample, and after homogenization and lyophilization of fish fillets, mercury concentrations were determined with a direct mercury analyzer utilizing the process of thermal combustion-gold amalgamation atomic absorption spectroscopy. Mercury concentrations in fish fillets from Folsom Reservoir ranged from 0.09 to 1.16 micrograms per gram wet weight, and from New Melones Reservoir ranged from 0.03 to 0.94 microgram per gram wet weight. Most of the fish fillets from Folsom Reservoir (87 percent) and 27 percent of the fillets from New Melones Reservoir exceeded the U.S. Environmental Protection Agency's fish consumption advisory of 0.30 microgram per gram wet weight.

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

    Science.gov (United States)

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

  18. Seasonal Variation of Total Mercury Burden in the American Alligator (Alligator Mississippiensis) at Merritt Island National Wildlife Refuge (MINWR), Florida

    Science.gov (United States)

    Nilsen, Frances M.; Dorsey, Jonathan E.; Long, Stephen E.; Schock, Tracey B.; Bowden, John A.; Lowers, Russell H.; Guillette, Louis J., Jr.

    2016-01-01

    Seasonal variation of mercury (Hg) is not well studied in free-ranging wildlife. Atmospheric deposition patterns of Hg have been studied in detail and have been modeled for both global and specific locations with great accuracy and correlates to environment impact. However, monitoring these trends in wildlife is complicated due to local environmental parameters (e.g., rainfall, humidity, pH, bacterial composition) that can affect the transformation of atmospheric Hg to the biologically available forms. Here, we utilized an abundant and healthy population of American alligators (Alligator mississippiensis) at Merritt Island National Wildlife Refuge (MINWR), FL, and assessed Hg burden in whole blood samples over a span of 7 years (2007 2014; n 174) in an effort to assess seasonal variation of total [Hg]. While the majority of this population is assumed healthy, 18 individuals with low body mass indices (BMI, defined in this study) were captured throughout the 7 year sampling period. These individual alligators exhibited [Hg] that were not consistent with the observed overall seasonal [Hg] variation, and were statistically different from the healthy population of alligators. The alligators with low BMI had elevated concentrations of Hg compared to their age/sex/season matched counterparts with normal BMI. Statistically significant differences were found between the winter and spring seasons for animals with normal BMI. The data in this report supports the conclusion that organismal total [Hg] do fluctuate directly with seasonal deposition rates as well as other seasonal environmental parameters, such as average rainfall and prevailing wind direction. This study highlights the unique environment of MINWR to permit annual assessment of apex predators, such as the American alligator, to determine detailed environmental impact of contaminants of concern.

  19. Landscape controls on total and methyl mercury in the upper Hudson River basin of New York State

    Science.gov (United States)

    Burns, D. A.; Murray, K. R.; Bradley, P. M.; Brigham, M. E.; Aiken, G.; Smith, M.

    2010-12-01

    High levels of mercury (Hg) in aquatic biota have been identified in surface waters of the Adirondack region of New York, and factors such as the prevalence of wetlands, extensive forest cover, and oligotrophic waters promote Hg bioaccumulation in this region. Past research in this region has focused on improved understanding of the Hg cycle in lake ecosystems. In the study described herein, the landscape controls on total Hg and methylmercury (MeHg) concentrations in riverine ecosystems were explored through synoptic surveys of 27 sites in the upper Hudson River basin of the Adirondack region. Stream samples were collected and analyzed for total Hg, MeHg, dissolved organic carbon (DOC), and ultraviolet absorbance at 254 nm (UV254) during spring and summer of 2006-08. Landscape indices including many common land cover, hydrographic, and topographic-based measures were explored as predictors of Hg through multivariate linear regression. Multivariate models that included a wetland or riparian area-based metric, an index for open water area, and in some cases a topographic metric such as the wetness index explained 55 to 65 percent of the variation in MeHg concentrations, and 55 to 80 percent of the variation in total Hg concentrations. An open water index (OWI) was developed that incorporated both the basin area drained by ponded water and the surface area of these ponds. This index was inversely related to concentrations of total Hg and MeHg. This OWI was also inversely related to specific ultra-violet absorbance, consistent with previous studies showing that open water increases the influence of algal-derived carbon on DOC, decreasing aromaticity, which should decrease the ability of the dissolved carbon pool to bind Hg. The OWI was not significant in models for total Hg that also included UV254 as a predictive variable, but the index did remain significant in similar models for MeHg suggesting that biogeochemical factors in addition to decreasing carbon

  20. Summary of total mercury concentrations in fillets of selected sport fishes collected during 2000-2003 from Lake Natoma, Sacramento County, California

    Science.gov (United States)

    Saiki, Michael K.; Slotton, Darrell G.; May, Thomas W.; Ayers, Shaun M.; Alpers, Charles N.

    2004-01-01

    This report summarizes results of total mercury measurements in skinless fillets of sport fishes collected during August 2000, September?October 2002, and July 2003 from Lake Natoma, a small (8,760 acre-feet) afterbay for Folsom Dam on the lower American River. The primary objective of the study was to determine if mercury concentrations in fillets approached or exceeded guidelines for human consumption. The Food and Drug Administration (FDA) human-health action level for methylmercury in commercially caught fish is 1.0 ?g/g (microgram per gram); the U.S. Environmental Protection Agency (USEPA) human-health criterion for methylmercury residue in fish tissue is 0.30 ?g/g. Wet weight concentrations of total mercury in skinless fillets were as high as 0.19 ?g/g in bluegill (Lepomis macrochirus), 0.39 ?g/g in redear sunfish (L. microlophus), 1.02 ?g/g in largemouth bass (Micropterus salmoides), and 1.89 ?g/g in channel catfish (Ictalurus punctatus). Maximum concentrations of mercury in other fish species varied from 0.10 ?g/g in rainbow trout (Oncorhynchus mykiss) to 0.56 ?g/g in white catfish (A-meiurus catus). Altogether, 1 of 86 largemouth bass and 11 of 11 channel catfish exceeded the FDA human-health action level. In addition, 1 of 20 redear sunfish, 26 of 86 largemouth bass, 2 of 3 spotted bass (M. punctulatus), 1 of 1 brown bullhead (A. nebulosus), and 1 of 1 white catfish exceeded the USEPA human-health criterion. These results indicate that some fish species inhabiting Lake Natoma contain undesirably high concentrations of mercury in their skinless fillets.

  1. Factorial design analysis on the solubility of total mercury in reduction process = Análise do processo experimental na solubilidade do mercúrio total em processo redutivo

    Directory of Open Access Journals (Sweden)

    Raquel Dalla Costa

    2007-07-01

    Full Text Available The dental wastewater can contribute to the total daily mercury load on the environment. Factorial design of experiments is useful to analyze factors that influence this solubility. The aim of the present study was to design experiments to examine the effects ofoperational variables, humic acid, temperature, pH and contact time that may affect the solubility of total mercury as dental amalgam residue in reduction process. Based on the factorial design of experiments, the humic acid concentration was the most significant factor in this process, followed by other factors. The parameters affecting the solubility of total mercury showed that when the [HA], T and CT increases and pH decreases there is an important increase of total mercury concentration in process. For the tested conditions, thehigh total mercury concentration was obtained using the humic acid concentration = 1.0 g L-1, temperature = 35oC, pH = 4.0 and contact time = 10 days.O esgoto odontológico pode contribuir na carga total de mercúrio noambiente. O estudo do planejamento experimental é útil para analisar os fatores que influenciam nesta solubilidade. O objetivo deste trabalho foi realizar um planejamento experimental para analisar os efeitos das variáveis operacionais, ácido húmico, temperatura,pH e tempo de contato, que podem afetar a solubilidade do mercúrio total como amálgama odontológico em um processo de redução. Baseado no planejamento experimental, a concentração de ácido húmico foi o fator mais significativo no processo, seguido dos demais fatores. Os parâmetros que afetam a solubilidade do mercúrio total mostram que quando a [AH], T e TC aumentam e o pH diminui há um aumento significativo na concentração de mercúrio total no processo. A maior concentração de mercúrio total foi obtido nas condições de concentração de ácido húmico = 1,0 g L-1, temperatura = 35oC, pH = 4,0 e tempo de contato = 10 dias.

  2. Total mercury concentrations in anadromous Northern Dolly Varden from the northwestern Canadian Arctic: A historical baseline study

    Energy Technology Data Exchange (ETDEWEB)

    Tran, L., E-mail: l5tran@uwaterloo.ca [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Reist, J.D. [Fisheries and Oceans Canada, Winnipeg, Manitoba R3T 2N6 (Canada); Power, M., E-mail: m3power@uwaterloo.ca [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2015-03-15

    Previous research has documented the significance of total mercury (THg) as a northern contaminant in general and of fish in particular. While much research has been devoted to documenting both spatial and temporal changes in THg in consumed fish, little effort has been directed at understanding patterns of THg in Dolly Varden (Salvelinus malma), a prized subsistence species throughout the western North American Arctic. Here we report historical THg concentrations for anadromous Dolly Varden from 10 populations in the Yukon and Northwest Territories sampled across a range of latitudes (67–69°N) and longitudes (136–141°W) between the years 1988–91. Unadjusted mean THg concentrations ranged from 15 to 254 ng/g wet weight. Length-adjusted THg concentrations were significantly different among sites, but were not related to latitude or longitude. Within and among populations, THg was significantly related to fork-length, age, δ{sup 15}N, and δ{sup 13}C, with the variation in THg found among populations being best explained by size. The data serve as an important baseline against which future changes in THg levels in this important subsistence fishery may be compared to determine the significance of any observed trends. - Highlights: • THg were measured in Dolly Varden from the Yukon and Northwest Territories. • Length-adjusted THg concentrations were not related to latitude or longitude. • Among-population variation in THg was best explained by fork-length. • Length-adjusted THg concentrations were related to age, δ{sup 15}N, and δ{sup 13}C. • Mean THg were below Health Canada’s consumption guideline for commercial fish.

  3. Total mercury concentrations in anadromous Northern Dolly Varden from the northwestern Canadian Arctic: A historical baseline study

    International Nuclear Information System (INIS)

    Tran, L.; Reist, J.D.; Power, M.

    2015-01-01

    Previous research has documented the significance of total mercury (THg) as a northern contaminant in general and of fish in particular. While much research has been devoted to documenting both spatial and temporal changes in THg in consumed fish, little effort has been directed at understanding patterns of THg in Dolly Varden (Salvelinus malma), a prized subsistence species throughout the western North American Arctic. Here we report historical THg concentrations for anadromous Dolly Varden from 10 populations in the Yukon and Northwest Territories sampled across a range of latitudes (67–69°N) and longitudes (136–141°W) between the years 1988–91. Unadjusted mean THg concentrations ranged from 15 to 254 ng/g wet weight. Length-adjusted THg concentrations were significantly different among sites, but were not related to latitude or longitude. Within and among populations, THg was significantly related to fork-length, age, δ 15 N, and δ 13 C, with the variation in THg found among populations being best explained by size. The data serve as an important baseline against which future changes in THg levels in this important subsistence fishery may be compared to determine the significance of any observed trends. - Highlights: • THg were measured in Dolly Varden from the Yukon and Northwest Territories. • Length-adjusted THg concentrations were not related to latitude or longitude. • Among-population variation in THg was best explained by fork-length. • Length-adjusted THg concentrations were related to age, δ 15 N, and δ 13 C. • Mean THg were below Health Canada’s consumption guideline for commercial fish

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

    Science.gov (United States)

    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

  5. Determination of total mercury for marine environmental monitoring studies by solid sampling continuum source high resolution atomic absorption spectrometry

    Science.gov (United States)

    Mandjukov, Petko; Orani, Anna Maria; Han, Eunmi; Vassileva, Emilia

    2015-01-01

    The most critical step in almost all commonly used analytical procedures for Hg determination is the sample preparation due to its extreme volatility. One of the possible solutions of this problem is the application of methods for direct analysis of solid samples. The possibilities for solid sampling high resolution continuum source atomic absorption spectrometry (HR CS AAS) determination of total mercury in various marine environmental samples e.g. sediments and biota are object of the present study. The instrumental parameters were optimized in order to obtain reproducible and interference free analytical signal. A calibration technique based on the use of solid standard certified reference materials similar to the nature of the analyzed sample was developed and applied to various CRMs and real samples. This technique allows simple and reliable evaluation of the uncertainty of the result and the metrological characteristics of the method. A validation approach in line with the requirements of ISO 17025 standard and Eurachem guidelines was followed. With this in mind, selectivity, working range (0.06 to 25 ng for biota and 0.025 to 4 ng for sediment samples, expressed as total Hg) linearity (confirmed by Student's t-test), bias (1.6-4.3%), repeatability (4-9%), reproducibility (9-11%), and absolute limit of detection (0.025 ng for sediment, 0.096 ng for marine biota) were systematically assessed using solid CRMs. The relative expanded uncertainty was estimated at 15% for sediment sample and 8.5% for marine biota sample (k = 2). Demonstration of traceability of measurement results is also presented. The potential of the proposed analytical procedure, based on solid sampling HR CS AAS technique was demonstrated by direct analysis of sea sediments form the Caribbean region and various CRMs. Overall, the use of solid sampling HR CS AAS permits obtaining significant advantages for the determination of this complex analyte in marine samples, such as straightforward

  6. Determination of total mercury for marine environmental monitoring studies by solid sampling continuum source high resolution atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mandjukov, Petko; Orani, Anna Maria; Han, Eunmi; Vassileva, Emilia, E-mail: e.vasileva-veleva@iaea.org

    2015-01-01

    The most critical step in almost all commonly used analytical procedures for Hg determination is the sample preparation due to its extreme volatility. One of the possible solutions of this problem is the application of methods for direct analysis of solid samples. The possibilities for solid sampling high resolution continuum source atomic absorption spectrometry (HR CS AAS) determination of total mercury in various marine environmental samples e.g. sediments and biota are object of the present study. The instrumental parameters were optimized in order to obtain reproducible and interference free analytical signal. A calibration technique based on the use of solid standard certified reference materials similar to the nature of the analyzed sample was developed and applied to various CRMs and real samples. This technique allows simple and reliable evaluation of the uncertainty of the result and the metrological characteristics of the method. A validation approach in line with the requirements of ISO 17025 standard and Eurachem guidelines was followed. With this in mind, selectivity, working range (0.06 to 25 ng for biota and 0.025 to 4 ng for sediment samples, expressed as total Hg) linearity (confirmed by Student's t-test), bias (1.6–4.3%), repeatability (4–9%), reproducibility (9–11%), and absolute limit of detection (0.025 ng for sediment, 0.096 ng for marine biota) were systematically assessed using solid CRMs. The relative expanded uncertainty was estimated at 15% for sediment sample and 8.5% for marine biota sample (k = 2). Demonstration of traceability of measurement results is also presented. The potential of the proposed analytical procedure, based on solid sampling HR CS AAS technique was demonstrated by direct analysis of sea sediments form the Caribbean region and various CRMs. Overall, the use of solid sampling HR CS AAS permits obtaining significant advantages for the determination of this complex analyte in marine samples, such as

  7. MEASUREMENT OF TOTAL SITE MERCURY EMISSIONS FROM A CHLOR-ALKALI PLANT USING OPEN-PATH UV-DOAS

    Science.gov (United States)

    In December 2003, the EPA promulgated the National Emission Standard for Hazardous Air Pollutants for mercury cell chlor-alkali plants. In February 2004, the Natural Resources Defense Council filed petitions on the final rule in U.S. district court citing, among other issues, th...

  8. Quantification of total mercury in liver and heart tissue of Harbor Seals (Phoca vitulina) from Alaska USA

    International Nuclear Information System (INIS)

    Marino, Kady B.; Hoover-Miller, Anne; Conlon, Suzanne; Prewitt, Jill; O'Shea, Stephen K.

    2011-01-01

    This study quantified the Hg levels in the liver (n=98) and heart (n=43) tissues of Harbor Seals (Phoca vitulina) (n=102) harvested from Prince William Sound and Kodiak Island Alaska. Mercury tissue dry weight (dw) concentrations in the liver ranged from 1.7 to 393 ppm dw, and in the heart from 0.19 to 4.99 ppm dw. Results of this study indicate liver and heart tissues' Hg ppm dw concentrations significantly increase with age. Male Harbor Seals bioaccumulated Hg in both their liver and heart tissues at a significantly faster rate than females. The liver Hg bioaccumulation rates between the harvest locations Kodiak Island and Prince William Sound were not found to be significantly different. On adsorption Hg is transported throughout the Harbor Seal's body with the partition coefficient higher for the liver than the heart. No significant differences in the bio-distribution (liver:heart Hg ppm dw ratios (n=38)) values were found with respect to either age, sex or geographic harvest location. In this study the age at which Hg liver and heart bioaccumulation levels become significantly distinct in male and female Harbor Seals were identified through a Tukey's analysis. Of notably concern to human health was a male Harbor Seal's liver tissue harvested from Kodiak Island region. Mercury accumulation in this sample tissue was determined through a Q-test to be an outlier, having far higher Hg concentrarion (liver 392 Hg ppm dw) than the general population sampled. - Highlights: ► Mercury accumulation in the liver and heart of seals exceed food safety guidelines. ► Accumulation rate is greater in males than females with age. ► Liver mercury accumulation is greater than in the heart tissues. ► Mercury determination by USA EPA Method 7473 using thermal decomposition.

  9. Identification of potential regional sources of atmospheric total gaseous mercury in Windsor, Ontario, Canada using hybrid receptor modeling

    Directory of Open Access Journals (Sweden)

    X. Xu

    2010-08-01

    Full Text Available Windsor (Ontario, Canada experiences trans-boundary air pollution as it is located on the border immediately downwind of industrialized regions of the United States of America. A study was conducted in 2007 to identify the potential regional sources of total gaseous mercury (TGM and investigate the effects of regional sources and other factors on seasonal variability of TGM concentrations in Windsor.

    TGM concentration was measured at the University of Windsor campus using a Tekran® 2537A Hg vapour analyzer. An annual mean of 2.02±1.63 ng/m3 was observed in 2007. The average TGM concentration was high in the summer (2.48±2.68 ng/m3 and winter (2.17±2.01 ng/m3, compared to spring (1.88±0.78 ng/m3 and fall (1.76±0.58 ng/m3. Hybrid receptor modeling potential source contribution function (PSCF was used by incorporating 72-h backward trajectories and measurements of TGM in Windsor. The results of PSCF were analyzed in conjunction with the Hg emissions inventory of North America (by state/province to identify regions affecting Windsor. In addition to annual modeling, seasonal PSCF modeling was also conducted. The potential source region was identified between 24–61° N and 51–143° W. Annual PSCF modeling identified major sources southwest of Windsor, stretching from Ohio to Texas. The emissions inventory also supported the findings, as Hg emissions were high in those regions. Results of seasonal PSCF modeling were analyzed to find the combined effects of regional sources, meteorological conditions, and surface re-emissions, on seasonal variability of Hg concentrations. It was found that the summer and winter highs of atmospheric Hg can be attributed to areas where large numbers of coal fired power plants are located in the USA. Weak atmospheric dispersion due to low winds and high re-emission from surfaces due to higher temperatures also contributed to high concentrations in

  10. Importance of Dissolved Neutral Hg-Sulfides, Energy Rich Organic Matter and total Hg Concentrations for Methyl Mercury Production in Sediments

    Science.gov (United States)

    Drott, A.; Skyllberg, U.

    2007-12-01

    Methyl mercury (MeHg) is the mercury form that biomagnifies to the greatest extent in aquatic food webs. Therefore information about factors determining MeHg concentrations is critical for accurate risk assessment of contaminated environments. The concentration of MeHg in wetlands and sediments is the net result of: 1) methylation rates, 2) demethylation rates, and 3) input/output processes. In this study, the main controls on Hg methylation rates and total concentrations of MeHg, were investigated at eight sites in Sweden with sediments that had been subjected to local Hg contamination either as Hg(0), or as phenyl-Hg. Sediments were selected to represent a gradient in total Hg concentration, temperature climate, salinity, primary productivity, and organic C content and quality. Most sediments were high in organic matter content due to wood fibre efflux from pulp and paper industry. The pore water was analysed for total Hg, MeHg, DOC, H2S(aq), pH, DOC, Cl and Br. The chemical speciation of Hg(II) and MeHg in pore water was calculated using equilibrium models. Potential methylation and demethylation rates in sediments were determined in incubation experiments at 23° C under N2(g) for 48 h, after addition of isotopically enriched 201Hg(II) and Me204Hg. In all surface (0-20 cm) sediments there was a significant (pdetermined specific potential methylation rate constant (Km, day-1) and % MeHg (concentrations of MeHg normalized to total Hg) in the sediment. This indicates that MeHg production overruled degradation and input/output processes of MeHg in surface sediments, and that % MeHg in surface sediments may be used as a proxy for net production of MeHg. To our knowledge, these are the first data showing significant positive relationships between short term (48 h) MeHg production and longer term accumulation of MeHg, across a range of sites with different properties (1). If MeHg was not normalized to total Hg, the relationship was not significant. For sub-sets of

  11. Determination of total mercury in seafood by ion-selective electrodes based on a thiol functionalized ionic liquid

    Directory of Open Access Journals (Sweden)

    Juan Miao

    2018-04-01

    Full Text Available A mercury(II ion-selective electrode with an ionic liquid (IL, 1-methyl-2-butylthioimidazolium bis(trifluoromethanesulphonylimide ([C1C4Sim]NTf2 as active material was constructed. Parameters affecting the performance of the electrodes such as the dosages of the IL and carbon nanotubes and the aqueous pH values were investigated. Experimental results indicated that the optimal composition of the electrode filling material was 47.6% [C1C4Sim]NTf2, 47.6% tetrabutylphosphonium bis(trifluoromethanesulphonylimide (TBPNTf2 and 4.8% carboxylic multi-walled carbon nanotubes (MWCNTs-COOH. Under the selected conditions, the proposed electrodes showed a good linear response in the concentration range of 10−10–10−5 mol L−1 and had a detection limit of 4.1 × 10−11 mol L−1. No great interference from common metal ions was found. The proposed electrodes were applied to determine Hg2+ in seafood samples; the results were comparable to those of the direct mercury analyzer. Keywords: Ionic liquids (ILs, Mercury, Ion-selective electrodes, Carbon nanotubes, Seafood

  12. Total mercury and methylmercury levels in pregnant women, nursing women and preschool children resident in fishing villages in the eighth region of Chile

    International Nuclear Information System (INIS)

    Bruhn, C.G.; Rodriguez, A.A.

    1992-01-01

    The main aim of this project is to perform a descriptive study about the levels of total mercury (Hg-T) and of methylmercury (Me-Hg) in scalp hair specimens of a selected human population of high risk in the Eighth Region of Chile, the group studied included pregnant women (PW), nursing women (NW) and preschool children residing in fishing villages distributed within the coastal zone of this region, the diets of the test group included fish and shellfish as main food components. The degree of Hg contamination of this population was compared to a control population (''core programme''). The methylmercury-to-total mercury ratio (Me-Hg/Hg-T) levels in scalp hair enabled interpretation of the results with respect to the degree of contamination by Hg, and the dietary habits of the sample donors of each fishing village under study. Furthermore, Se levels in scalp hair of the populations with relatively high Hg content were to be investigated for possible correlation with Me-Hg levels (''supplementary programme''). 5 refs, 2 figs, 9 tabs

  13. Total- and methyl-mercury concentrations and methylation rates across the freshwater to hypersaline continuum of the Great Salt Lake, Utah, USA

    Science.gov (United States)

    Johnson, William P.; Swanson, Neil; Black, Brooks; Rudd, Abigail; Carling, Gregory; Fernandez, Diego P.; Luft, John; Van Leeuwen, Jim; Marvin-DiPasquale, Mark C.

    2015-01-01

    We examined mercury (Hg) speciation in water and sediment of the Great Salt Lake and surrounding wetlands, a locale spanning fresh to hypersaline and oxic to anoxic conditions, in order to test the hypothesis that spatial and temporal variations in Hg concentration and methylation rates correspond to observed spatial and temporal trends in Hg burdens previously reported in biota. Water column, sediment, and pore water concentrations of methylmercury (MeHg) and total mercury (THg), as well as related aquatic chemical parameters were examined. Inorganic Hg(II)-methylation rates were determined in selected water column and sediment subsamples spiked with inorganic divalent mercury (204Hg(II)). Net production of Me204Hg was expressed as apparent first-order rate constants for methylation (kmeth), which were also expanded to MeHg production potential (MPP) rates via combination with tin reducible ‘reactive’ Hg(II) (Hg(II)R) as a proxy for bioavailable Hg(II). Notable findings include: 1) elevated Hg concentrations previously reported in birds and brine flies were spatially proximal to the measured highest MeHg concentrations, the latter occurring in the anoxic deep brine layer (DBL) of the Great Salt Lake; 2) timing of reduced Hg(II)-methylation rates in the DBL (according to both kmeth and MPP) coincides with reduced Hg burdens among aquatic invertebrates (brine shrimp and brine flies) that act as potential vectors of Hg propagation to the terrestrial ecosystem; 3) values ofkmeth were found to fall within the range reported by other studies; and 4) MPP rates were on the lower end of the range reported in methodologically comparable studies, suggesting the possibility that elevated MeHg in the anoxic deep brine layer results from its accumulation and persistence in this quasi-isolated environment, due to the absence of light (restricting abiotic photo demethylation) and/or minimal microbiological demethylation.

  14. Mercúrio total em cabelos: uma contribuição para se avaliar o nível de exposição em Poconé, Mato Grosso, Brasil Total mercury in hair: a contribution to the evaluation of mercury exposure levels in Poconé, Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Flávia Nogueira

    1997-10-01

    Full Text Available Ocorrem na Bacia do Rio Bento Gomes (MT, às margens do Pantanal Mato-grossense, cerca de sessenta garimpos de ouro, onde o mercúrio é utilizado de forma intensiva nos processos de produção, através da formação de amálgamas que facilitam a aglutinação de partículas finas. A queima do amálgama nem sempre é feita em sistemas fechados de recuperação, havendo, portanto, perda de vapor para a atmosfera. Este estudo traz resultados de análises de mercúrio total nos cabelos de quatro grupos de voluntários que vivem em Poconé (MT, e faz uma caracterização geral do ambiente no que se refere à presença do metal na água e no sedimento do Rio Bento Gomes. Um equipamento de detecção por fluorescência foi usado para a determinação das concentrações, e os resultados indicam que os valores são mais baixos do que os de outras populações de áreas de garimpo no Brasil. Indicam também que a via ocupacional parece ser a mais eficiente rota potencial de contaminação da população por mercúrio.There are some 60 gold-mining sites in the Bento Gomes River basin (Mato Grosso, at the border of the Mato Grosso Pantanal (Swamp, where mercury is used to agglutinate fine gold particles through amalgamation. During burning of the amalgam to release the gold, mercury vapor is lost to the atmosphere, since closed systems for mercury recovery are not always used. This study shows the results of total mercury analysis in hair from four volunteer groups living in Poconé, Mato Grosso, and presents a general environmental description pertaining to the presence of mercury in water and sediments from the Bento Gomes River. Atomic fluorescence was used for measuring mercury concentrations. The results were lower than for other populations from gold-mining areas in Brazil.

  15. Mercury balance analysis

    International Nuclear Information System (INIS)

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

    1996-01-01

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

  16. Total gaseous mercury and volatile organic compounds measurements at five municipal solid waste disposal sites surrounding the Mexico City Metropolitan Area

    Science.gov (United States)

    de la Rosa, D. A.; Velasco, A.; Rosas, A.; Volke-Sepúlveda, T.

    The daily municipal solid waste (MSW) generation in the Mexico City Metropolitan Area (MCMA) is the highest nationwide (˜26000 ton day -1); this amount is discarded in sanitary landfills and controlled dumps. Information about the type and concentration of potential pollutants contained in landfill gas (LFG) from these MSW disposal sites is limited. This study intends to generate information about the composition of LFG from five MSW disposal sites with different operational characteristics and stages, in order to identify their contribution as potential pollutant sources of total gaseous mercury (TGM) and volatile organic compounds (VOCs). Important methane (CH 4) contents (>55%) in LFG were registered at three of the five sites, while two sites were found in semi-aerobic conditions (CH 4clay cover. High values of the TGM air/LFG ratio were also related to external TGM sources of influence, as a landfill in operation stage located at a highly industrialized area.

  17. Study on total and methyl mercury levels in human scalp hairs of lying-in women and newborns by NAA and other techniques

    International Nuclear Information System (INIS)

    Chai Chifang; Feng Weiye; Qian Qinfang; Guan Ming; Li Xinji; Lu Yilun; Zhang Xioumei

    1995-01-01

    Since the Second Research Co-ordinating Meeting in Malaysia, 24-28 August 1992, our research group has completed the analysis of total and methylmercury in scalp hair samples of 1179 fishermen living at a typical Hg-polluted region in Northeast China and of 27 lying-in women and their newborns in a Beijing hospital by INAA, GC(EC) and other techniques. The longitudinal Hg patterns of the lying-in women show a gradually decreasing tendency during the pregnancy period. Further, the hair Hg contents of the newborn babies are generally above or close to those of their mothers, confirming the mechanism that the methylmercury, an organic species of Hg with high toxicity, is readily able to penetrate the placental barrier and accumulate in the fetus. Thus, the mercury exposure has occurred at the early stage of pregnancy. (author)

  18. Total mercury in sharks along the southern Brazilian Coast Mercúrio total em tubarões capturados na costa brasileira

    Directory of Open Access Journals (Sweden)

    E.T. Mársico

    2007-12-01

    Full Text Available Pesquisou-se a concentração de mercúrio total na porção muscular de 39 exemplares de tubarões de três diferentes espécies Prionace glauca, Isurus oxyrhynchus, Sphyrna zygaena, capturados na costa sul do Brasil, Santa Catarina. O teor de mercúrio foi determinado por espectrofotometria de absorção atômica por vapor frio. Observou-se ampla variação na concentração de mercúrio total com valor individual máximo excedendo o limite estabelecido pela legislação brasileira, de 1.0µg.g-1 em um exemplar fêmea de P. glauca. Nessa espécie, a concentração de Hg-total aumentou proporcionalmente ao comprimento total (r=0,62; P<0,0001. Não foi evidenciada diferença estatisticamente significativa entre exemplares fêmeas e machos.

  19. Measurement of Total Site Mercury Emissions from a Chlor-Alkali Plant Using Ultraviolet Differential Optical Absorption Spectroscopy and Cell Room Roof-Vent Monitoring

    Science.gov (United States)

    Mercury-cell chlor-alkali plants can emit significant quantities of fugitive elemental mercury vapor to the air as part of production operations and maintenance activities. In the fall of 2006, the U.S. Environmental Protection Agency (EPA) conducted a measurement project at a ch...

  20. Measurement of Total Site Mercury Emissions from Chlor-Alkali Plant Using Ultraviolet Differential Optical Absorption Spectroscopy and Cell Room Roof-Vent Monitoring

    Science.gov (United States)

    This technical note describes a United States Environmental Protection Agency (U.S. EPA) measurement project to determine elemental mercury (Hg0) emissions from a mercury cell chlor-alkali (MCCA) facility in the southeastern U.S. during a 53-day monitoring campaign in the fall of...

  1. Evaluation of the trace elements and the total mercury concentration in fishes commercialized at the Cubatao city, Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Fonseca, Barbara C.; Farias, Luciana A.; Curcho, Michel R.M.; Favaro, Debora I.T.; Braga, Elisabete S.

    2009-01-01

    This paper evaluates the total Hg and the trace elements As, Br, Co, Cr and Rb concentrations in muscle of commercially important fishes at the Cubatao, Sao Paulo, Brazil, region. The following carnivore species were analysed: jew fish (Micropogonias furnieri), girl leg (Menticirrhus americanus), hake (Macrodon ancylodon), and plant eaters, sardine (Sardella braziliensis) and grey mullet (Mugil liza), representing a total of 58 samples. The analysed trace elements were determined through the neutron analysis activation (NAA) and total Hg, through the atomic absorption spectrometry with cold vapor generation (CV AAS). The analysed elements present a great concentration variation, not only among individuals of the same specie, but also among all the analysed species. The total Hg concentration were highly significant, with the predator species jew fish, girl leg and hake presenting concentrations larger than the non predator species sardine and grey mullet. Nevertheless, the content of total Hg remained bellow the limits established by the Brazilian legislation which is the 500 μg kg -1 for the non predator species, and the 1000 μg -1 for the predator species (humid weight)

  2. Mercury concentrations in water resources potentially impacted by coal-fired power stations and artisanal gold mining in Mpumalanga, South Africa

    CSIR Research Space (South Africa)

    Williams, CR

    2010-09-01

    Full Text Available , 24% of TotHg concentrations in sediment. Methylmercury concentrations were not correlated with TotHg concentrations or organic content in sediment. The concentration of MeHg in invertebrates and fish were highest in the Inkomati WMA and, furthermore...

  3. Mercury and Your Health

    Science.gov (United States)

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

  4. Total mercury and methylmercury in fish fillets, water, and bed sediments from selected streams in the Delaware River basin, New Jersery, New York, and Pennsylvania, 1998-2001

    Science.gov (United States)

    Brightbill, Robin A.; Riva-Murray, Karen; Bilger, Michael D.; Byrnes, John D.

    2004-01-01

    Within the Delaware River Basin, fish-tissue samples were analyzed for total mercury (tHg). Water and bed-sediment samples were analyzed for tHg and methylmercury (MeHg), and methylation efficiencies were calculated. This study was part of a National Mercury Pilot Program conducted by the U.S. Geological Survey (USGS). The Delaware River Basin was chosen because it is part of the USGS National Water-Quality Assessment Program that integrates physical, chemical, and biological sampling efforts to determine status and trends in surface-water and ground-water resources. Of the 35 sites in the study, 31 were sampled for fish. The species sampled at these sites include smallmouth bass (Micropterus dolomieu), the target species, and where smallmouth bass could not be collected, brown trout (Salmo trutta), chain pickerel (Esox niger), largemouth bass (Micropterus salmoides), and rock bass (Ambloplites rupestris). There were a total of 32 fish samples; 7 of these exceeded the 0.3 ?g/g (micrograms per gram) wet-weight mercury (Hg) concentration set for human health by the U.S. Environmental Protection Agency and 27 of these exceeded the U.S. Fish and Wildlife Service criteria of 0.1 ?g/g wet weight for the protection of fish-eating birds and wildlife. Basinwide analysis of Hg in fish, water, and bed sediment showed tHg concentration in fillets correlated positively with population density, urban land cover, and impervious land surface. Negative correlations included wetland land cover, septic density, elevation, and latitude. Smallmouth bass from the urban sites had a higher median concentration of tHg than fish from agricultural, low intensity-agricultural, or forested sites. Concentrations of tHg and MeHg in water were higher in samples from the more urbanized areas of the basin and were positively correlated with urbanization and negatively correlated with forested land cover. Methylation efficiency of water was negatively correlated with urbanization. Bed

  5. Determination of total cadmium, lead, arsenic, mercury and inorganic arsenic in mushrooms: outcome of IMEP-116 and IMEP-39.

    Science.gov (United States)

    Cordeiro, F; Llorente-Mirandes, T; López-Sánchez, J F; Rubio, R; Sánchez Agullo, A; Raber, G; Scharf, H; Vélez, D; Devesa, V; Fiamegos, Y; Emteborg, H; Seghers, J; Robouch, P; de la Calle, M B

    2015-01-01

    The Institute for Reference Materials and Measurements (IRMM) of the Joint Research Centre (JRC), a Directorate General of the European Commission, operates the International Measurement Evaluation Program (IMEP). IMEP organises inter-laboratory comparisons in support of European Union policies. This paper presents the results of two proficiency tests (PTs): IMEP-116 and IMEP-39, organised for the determination of total Cd, Pb, As, Hg and inorganic As (iAs) in mushrooms. Participation in IMEP-116 was restricted to National Reference Laboratories (NRLs) officially appointed by national authorities in European Union member states. IMEP-39 was open to all other laboratories wishing to participate. Thirty-seven participants from 25 countries reported results in IMEP-116, and 62 laboratories from 36 countries reported for the IMEP-39 study. Both PTs were organised in support to Regulation (EC) No. 1881/2006, which sets the maximum levels for certain contaminants in food. The test item used in both PTs was a blend of mushrooms of the variety shiitake (Lentinula edodes). Five laboratories, with demonstrated measurement capability in the field, provided results to establish the assigned values (Xref). The standard uncertainties associated to the assigned values (uref) were calculated by combining the uncertainty of the characterisation (uchar) with a contribution for homogeneity (ubb) and for stability (ust), whilst uchar was calculated following ISO 13528. Laboratory results were rated with z- and zeta (ζ)-scores in accordance with ISO 13528. The standard deviation for proficiency assessment, σp, ranged from 10% to 20% depending on the analyte. The percentage of satisfactory z-scores ranged from 81% (iAs) to 97% (total Cd) in IMEP-116 and from 64% (iAs) to 84% (total Hg) in IMEP-39.

  6. Total Mercury in Squalid Callista Megapitaria squalida from the SW Gulf of California, Mexico: Tissue Distribution and Human Health Risk.

    Science.gov (United States)

    Romo-Piñera, Abril K; Escobar-Sánchez, Ofelia; Ruelas-Inzunza, Jorge; Frías-Espericueta, Martín G

    2018-03-01

    We evaluated the total Hg concentration in different tissues of squalid callista Megapitaria squalida in order to measure Hg distribution in tissue and to estimate human health risk. Samples were obtained by free diving in the SW Gulf of California, Mexico. Concentrations are given on a wet weight basis. A total of 89 squalid callista specimens were obtained, presenting an average Hg concentration of 0.07 ± 0.04 µg g -1 . There were no significant differences (p > 0.05) in Hg concentration between tissues (visceral mass = 0.09 ± 0.08 µg g -1 ; mantle = 0.06 ± 0.07 µg g -1 ; muscle = 0.06 ± 0.04 µg g -1 ). The low Hg values found in squalid callista and its low risk quotient (HQ = 0.03) suggest that the consumption of squalid callista does not represent a human health risk. However, HQ calculated using MeHg was > 1, it which could indicate a potential risk related to consumption of clams.

  7. Estimation of uncertainty of a reference material for proficiency testing for the determination of total mercury in fish in natura; Estimativa da incerteza de um material de referencia para ensaios de proficiencia para a determinacao de mercurio total em pescado in natura

    Energy Technology Data Exchange (ETDEWEB)

    Santana, L.V.; Sarkis, J.E.S.; Ulrich, J.C.; Hortellani, M.A., E-mail: santana-luciana@ig.com.br, E-mail: jesarkis@ipen.br, E-mail: jculrich@ipen.br, E-mail: mahortel@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    This study presents the uncertainty estimate for characterization, study of homogeneity and stability study obtained in the preparation of a reference material for the determination of total mercury in fish fresh muscle tissue for proficiency testing. The test results for stability were obtained by linear regression and to homogeneity study was obtained by ANOVA-one way showed that the material is homogeneous and stable. The value of total mercury concentration with expanded uncertainty for the material was 0,294 ± 0,089 μg g{sup -}. (author)

  8. Chemometrics methods for the investigation of methylmercury and total mercury contamination in mollusks samples collected from coastal sites along the Chinese Bohai Sea

    International Nuclear Information System (INIS)

    Wang Yawei; Liang Lina; Shi Jianbo; Jiang Guibin

    2005-01-01

    The development and application of chemometrics methods, principal component analysis (PCA), cluster analysis and correlation analysis for the determination of methylmercury (MeHg) and total mercury (HgT) in gastropod and bivalve species collected from eight coastal sites along the Chinese Bohai Sea are described. HgT is directly determined by atomic fluorescence spectrometry (AFS), while MeHg is measured by a laboratory established high performance liquid chromatography-atomic fluorescence spectrometry system (HPLC-AFS). One-way ANOVA and cluster analysis indicated that the bioaccumulation of Rap to accumulate Hg was significantly (P<0.05) different from other mollusks. Correlation analysis shows that there is linear relationship between MeHg and HgT in mollusks samples collected from coastal sites along the Chinese Bohai Sea, while in mollusks samples collected from Hongqiao market in Beijing City, there is not any linear relationship. - Rapana venosa might be used as a potential biomonitor for Hg pollution in the Bohai Sea, China

  9. Total mercury and methylmercury levels in pregnant women, nursing women and preschool children - residents of fisheries in the eighth region of Chile

    International Nuclear Information System (INIS)

    Bruhn, C.G.; Rodriguez, A.A.; Barrios, C.A.; Gras, N.T.; Becerra, J.; Nunez, E.; Reyes, O.C.

    1995-01-01

    In the 1991-1993 period, efforts were concentrated on establishing and validating the analytical methodology for determining total mercury (Hg-T) and methylmercury (MeHg) in human hair, and to identify any high risk populations in the study group. Two surveys were conducted during this period, which involved the collection of scalp hair samples that were prepared and analyzed for Hg-T, and also for MeHg in selected samples. The mean hair Hg-T concentration determined in the study group (1.81 ± 1.52 mg/kg, as dry weight) was significantly higher than the level obtained in the control group (0.42 ± 0.15 mg/kg). These results were characterized according to geographical location of the FVs, frequency of fish and seafood consumption and residence period in the same FV. Multiple comparison tests confirmed significant differences between the arithmetic means obtained in each FV and the control group. Five of the FVs with higher Hg-T concentrations in PW and NW were selected for further and more in-depth studies. A new survey, which is now in progress, is also described, which targets these five FVs and the associated control group. (author)

  10. Planet Mercury

    Science.gov (United States)

    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.

  11. The evaluation of total mercury and arsenic in skin bleaching creams commonly used in Trinidad and Tobago and their potential risk to the people of the Caribbean

    Directory of Open Access Journals (Sweden)

    Terry Mohammed

    2017-10-01

    Full Text Available Background. Skin lightening is very popular among women and some men of the Caribbean, and its popularity appears to be growing. The lightening of skin colour is done to produce a lighter complexion which is believed to increase attractiveness, social standing and improves one’s potential of being successful. Design and Methods. Fifteen (15 common skin lightening creams found in pharmacies and cosmetic retailers throughout Trinidad and Tobago were evaluated for Mercury by Cold Vapor Atomic Absorption Spectrophotometry (CVAAS and Arsenic by Hydride Generation Atomic Absorption Spectrophotometry (HGAAS. The results obtained were compared to global standards and previous research. Results. Fourteen (14 of the fifteen samples analysed contained Mercury in the range of 0.473 μg/g to 0.766 μg/g. One sample had a Mercury content of 14,507.74±490.75 μg/g which was over 14,000 times higher than the USFDA limit for mercury in cosmetics of 1 μg/g. All samples contained Arsenic in the range 1.016 μg/g to 6.612 μg/g, which exceeds the EU limit for cosmetics of 0 μg/g. Conclusions. All the samples analysed contained significant amounts of Mercury and Arsenic and none of them can be considered safe for prolonged human use. The samples that contained Mercury levels which were lower than the USFDA limit contained Arsenic levels which exceeded the EU standard of 0 μg/g in cosmetics. The popularity of these skin lightening creams in the Caribbean region places the population at elevated risk of chronic Mercury and Arsenic poisoning and possibly acute Mercury Poisoning.

  12. The evaluation of total mercury and arsenic in skin bleaching creams commonly used in Trinidad and Tobago and their potential risk to the people of the Caribbean.

    Science.gov (United States)

    Mohammed, Terry; Mohammed, Elisabeth; Bascombe, Shermel

    2017-12-13

    Background. Skin lightening is very popular among women and some men of the Caribbean, and its popularity appears to be growing. The lightening of skin colour is done to produce a lighter complexion which is believed to increase attractiveness, social standing and improves one's potential of being successful. Design and Methods. Fifteen (15) common skin lightening creams found in pharmacies and cosmetic retailers throughout Trinidad and Tobago were evaluated for Mercury by Cold Vapor Atomic Absorption Spectrophotometry (CVAAS) and Arsenic by Hydride Generation Atomic Absorption Spectrophotometry (HGAAS). The results obtained were compared to global standards and previous research. Results. Fourteen (14) of the fifteen samples analysed contained Mercury in the range of 0.473 μg/g to 0.766 μg/g. One sample had a Mercury content of 14,507.74±490.75 μg/g which was over 14,000 times higher than the USFDA limit for mercury in cosmetics of 1 μg/g. All samples contained Arsenic in the range 1.016 μg/g to 6.612 μg/g, which exceeds the EU limit for cosmetics of 0 μg/g. Conclusions. All the samples analysed contained significant amounts of Mercury and Arsenic and none of them can be considered safe for prolonged human use. The samples that contained Mercury levels which were lower than the USFDA limit contained Arsenic levels which exceeded the EU standard of 0 μg/g in cosmetics. The popularity of these skin lightening creams in the Caribbean region places the population at elevated risk of chronic Mercury and Arsenic poisoning and possibly acute Mercury Poisoning.

  13. Mercurial poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Gorton, B

    1924-01-01

    Cats which had been kept in a thermometer factory to catch rats were afflicted with mercury poisoning. So were the rats they were supposed to eat. The symptoms of mercury poisoning were the same in both species. The source of mercury for these animals is a fine film of the metal which coats floors, a result of accidental spills during the manufacturing process.

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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

  15. Mercury in Canadian crude oil

    International Nuclear Information System (INIS)

    Hollebone, B.P.

    2005-01-01

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

  16. Determination of total and organic mercury and evaluation of methylation and demethylation processes in sediments of the Rio Grande Reservoir, State of Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Franklin, Robson Leocadio

    2010-01-01

    The Rio Grande reservoir is located in the metropolitan area of Sao Paulo and it is a very important water supply for this region. In the present study bottom waters and sediment samples collected in this reservoir, in four sampling points, in four campaigns, from September 2008 to January 2010, were analyzed. Firstly total Hg was determined in sediment and bottom waters by cold vapor atomic absorption technique (CV AAS). Following, the analytical methodology for organic Hg was adapted from literature, where the organomercurial compounds were extracted with dichloromethane in acid medium and subsequent destruction of organic compounds by bromine chloride. The validation of this methodology, in terms of precision and accuracy, was performed by means of IAEA 405 and BCR-CRM 580 reference materials analyses. For methylation and demethylation processes evaluation in this environment, the following physical and chemical parameters were assessed, in situ: pH, water temperature, redox potential (EH), transparency and depth. For the sediment samples, granulometry, total organic carbon, sulphate-reducing bacteria, total N and P, besides the metals Co, Cu, Fe and Mn were evaluated. The selection of these parameters was related to the factors that influence the behavior of MeHg in the sediments and its transition zone. Total Hg ranging from 1.0 to 71.0 mg kg'- 1 and organic mercury from -1 in sediments and methylation rates from 0.06 to 1.4% were found, along the reservoir. Different methylation conditions along the reservoir and its influences were also discussed. As supplementary study the concentration of some metals and trace elements in the sediments by neutron activation analysis technique was determined. As, Ba, Br, Co, Cr, Cs, Hf, Fe, Na, Rb, Sb, Sc and Zn and rare earth elements Ce, Eu, La, Lu, Nd, Sm and Yb were determined. The enrichment factor in relation to earth crust values using Sc as normalizer element reached values higher than 2.0 for the elements As, Br

  17. Total mercury and methylmercury accumulation in wild plants grown at wastelands composed of mine tailings: Insights into potential candidates for phytoremediation.

    Science.gov (United States)

    Qian, Xiaoli; Wu, Yonggui; Zhou, Hongyun; Xu, Xiaohang; Xu, Zhidong; Shang, Lihai; Qiu, Guangle

    2018-08-01

    Total mercury (THg) and methylmercury (MMHg) were investigated in 259 wild plants belonging to 49 species in 29 families that grew in heavily Hg-contaminated wastelands composed of cinnabar ore mine tailings (calcines) in the Wanshan region, southwestern China, the world's third largest Hg mining district. The bioconcentration factors (BCFs) of THg and MMHg from soil to roots ([THg] root /[THg] soil , [MMHg] root /[MMHg] soil ) were evaluated. The results showed that THg and MMHg in both plants and soils varied widely, with ranges of 0.076-140 μg/g THg and 0.19-87 ng/g MMHg in roots, 0.19-106 μg/g THg and 0.06-31 ng/g MMHg in shoots, and 0.74-1440 μg/g THg and 0.41-820 ng/g MMHg in soil. Among all investigated species, Arthraxon hispidus, Eremochloa ciliaris, Clerodendrum bunge, and Ixeris sonchifolia had significantly elevated concentrations of THg in shoots and/or roots that reached 100 μg/g, whereas Chenopodium glaucum, Corydalisedulis maxim, and Rumex acetosa contained low values below 0.5 μg/g. In addition to the high THg concentrations, the fern E. ciliaris also showed high BCF values for both THg and MMHg exceeding 1.0, suggesting its capability to extract Hg from soils. Considering its dominance and the tolerance identified in the present study, E. ciliaris is suggested to be a practical candidate for phytoextraction, whereas A. hispidus is identified as a potential candidate for phytostabilization of Hg mining-contaminated soils. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Validation of an analytical method for the determination of total mercury in urine samples using cold vapor atomic absorption spectrometry (CV-AAS)

    International Nuclear Information System (INIS)

    Guilhen, Sabine Neusatz

    2009-01-01

    Mercury (Hg) is a toxic metal applied to a variety of products and processes, representing a risk to the health of occupationally or accidentally exposed subjects. Dental amalgam is a restorative material composed of metallic mercury, which use has been widely debated in the last decades. Due to the dubiety of the studies concerning dental amalgam, many efforts concerning this issue have been conducted. The Tropical Medicine Foundation (Tocantins, Brazil) has recently initiated a study to evaluate the environmental and occupational levels of exposure to mercury in dentistry attendants at public consulting rooms in the city of Araguaina (TO). In collaboration with this study, the laboratory of analysis at IPEN's Chemistry and Environment Center is undertaking the analysis of mercury levels in exposed subjects' urine samples using cold vapor atomic absorption spectrometry. This analysis requires the definition of a methodology capable of generating reliable results. Such methodology can only be implemented after a rigorous validation procedure. As part of this work, a series of tests were conducted in order to confirm the suitability of the selected methodology and to assert that the laboratory addresses all requirements needed for a successful implementation of the methodology. The following parameters were considered in order to test the method's performance: detection and quantitation limits, selectivity, sensitivity, linearity, accuracy and precision. The assays were carried out with certified reference material, which assures the traceability of the results. Taking into account the estimated parameters, the method can be considered suitable for the afore mentioned purpose. The mercury concentration found for the reference material was of (95,12 +- 11,70)mug.L -1 with a recovery rate of 97%. The method was also applied to 39 urine samples, six of which (15%) showing urinary mercury levels above the normal limit of 10μg.L -1 . The obtained results fall into a

  19. MODELING MERCURY CONTROL WITH POWDERED ACTIVATED CARBON

    Science.gov (United States)

    The paper presents a mathematical model of total mercury removed from the flue gas at coal-fired plants equipped with powdered activated carbon (PAC) injection for Mercury control. The developed algorithms account for mercury removal by both existing equipment and an added PAC in...

  20. Mercury content of shark from south-western Australian waters

    Energy Technology Data Exchange (ETDEWEB)

    Caputi, N.; Edmonds, J.S.; Heald, D.I.

    1979-11-01

    Muscle samples from four species of commercially sought sharks off the Western Australia coast were analyzed for total mercury. While substantial amounts of mercury were accumulated by sharks, as by other marine fish, the lack of polluting industry on the coast indicates that such mercury levels probably are natural. Mercury concentrations generally increased with fish size. (4 graphs, 1 map, 8 references, 2 tables)

  1. Total- and monomethyl-mercury and major ions in coastal California fog water: Results from two years of sampling on land and at sea

    Directory of Open Access Journals (Sweden)

    Peter Weiss-Penzias

    2016-04-01

    Full Text Available Abstract Marine fog water samples were collected over two summers (2014–2015 with active strand collectors (CASCC at eight coastal sites from Humboldt to Monterey counties in California, USA, and on four ocean cruises along the California coastline in order to investigate mercury (Hg cycling at the ocean-atmosphere-land interface. The mean concentration of monomethylmercury (MMHg in fog water across terrestrial sites for both years was 1.6 ± 1.9 ng L-1 (<0.01–10.4 ng L-1, N = 149, which corresponds to 5.7% (2.0–10.8% of total Hg (HgT in fog. Rain water samples from three sites had mean MMHg concentrations of 0.20 ± 0.12 ng L-1 (N = 5 corresponding to 1.4% of HgT. Fog water samples collected at sea had MMHg concentrations of 0.08 ± 0.15 ng L-1 (N = 14 corresponding to 0.4% of HgT. Significantly higher MMHg concentrations in fog were observed at terrestrial sites next to the ocean relative to a site 40 kilometers inland, and the mean difference was 1.6 ng L-1. Using a rate constant for photo-demethylation of MMHg of -0.022 h-1 based on previous demethylation experiments and a coastal-inland fog transport time of 12 hours, a mean difference of only 0.5 ng L-1 of MMHg was predicted between coastal and inland sites, indicating other unknown source and/or sink pathways are important for MMHg in fog. Fog water deposition to a standard passive 1.00 m2 fog collector at six terrestrial sites averaged 0.10 ± 0.07 L m-2 d-1, which was ∼2% of typical rainwater deposition in this area. Mean air-surface fog water fluxes of MMHg and HgT were then calculated to be 34 ± 40 ng m-2 y-1 and 546 ± 581 ng m-2 y-1, respectively. These correspond to 33% and 13% of the rain fluxes, respectively.

  2. Spatial variation of mercury bioaccumulation in bats of Canada linked to atmospheric mercury deposition.

    Science.gov (United States)

    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

  3. Methyl mercury in terrestrial compartments

    International Nuclear Information System (INIS)

    Stoeppler, M.; Burow, M.; Padberg, S.; May, K.

    1993-09-01

    On the basis of the analytical methodology available at present the state of the art for the determination of total mercury and of various organometallic compounds of mercury in air, precipitation, limnic systems, soils, plants and biota is reviewed. This is followed by the presentation and discussion of examples for the data obtained hitherto for trace and ultratrace levels of total mercury and mainly methyl mercury in terrestrial and limnic environments as well as in biota. The data discussed stem predominantly from the past decade in which, due to significant methodological progress, many new aspects were elucidated. They include the most important results in this area achieved by the Research Centre (KFA) Juelich within the project 'Origin and Fate of Methyl Mercury' (contracts EV4V-0138-D and STEP-CT90-0057) supported by the Commission of the European Communities, Brussels. (orig.) [de

  4. The evaluation of total mercury and arsenic in skin bleaching creams commonly used in Trinidad and Tobago and their potential risk to the people of the Caribbean

    OpenAIRE

    Terry Mohammed; Elisabeth Mohammed; Shermel Bascombe

    2017-01-01

    Background. Skin lightening is very popular among women and some men of the Caribbean, and its popularity appears to be growing. The lightening of skin colour is done to produce a lighter complexion which is believed to increase attractiveness, social standing and improves one’s potential of being successful. Design and Methods. Fifteen (15) common skin lightening creams found in pharmacies and cosmetic retailers throughout Trinidad and Tobago were evaluated for Mercury by Cold Vapor Atomic A...

  5. Determination of the total mercury in contaminated soils by direct solid sampling atomic absorption spectrometry using an AMA-254 device and radiochemical neutron activation analysis

    Czech Academy of Sciences Publication Activity Database

    Sysalová, J.; Kučera, Jan; Fikrle, Marek; Drtinová, B.

    2013-01-01

    Roč. 110, SEP (2013), s. 691-694 ISSN 0026-265X R&D Projects: GA ČR GAP503/12/0682; GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:61389005 Keywords : Mercury * contaminated soils * AMA-254 * RNAA Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.583, year: 2013

  6. Mercury pollution in Malaysia.

    Science.gov (United States)

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

    2012-01-01

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

  7. Quarter 9 Mercury information clearinghouse final report

    Energy Technology Data Exchange (ETDEWEB)

    Laudal, D.L.; Miller, S.; Pflughoeft-Hassett, D.; Ralston, N.; Dunham, G.; Weber, G.

    2005-12-15

    The Canadian Electricity Association (CEA) identified a need and contracted the Energy & Environmental Research Center (EERC) to create and maintain an information clearinghouse on global research and development activities related to mercury emissions from coal-fired electric utilities. A total of eight reports were completed and are summarized and updated in this final CEA quarterly report. Selected topics were discussed in detail in each quarterly report. Issues related to mercury from coal-fired utilities include the general areas of measurement, control, policy, and transformations. Specific topics that have been addressed in previous quarterly reports include the following: Quarterly 1 - Sorbent Control Technologies for Mercury Control; Quarterly 2 - Mercury Measurement; Quarterly 3 - Advanced and Developmental Mercury Control Technologies; Quarterly 4 - Prerelease of Mercury from Coal Combustion By-Products; Quarterly 5 - Mercury Fundamentals; Quarterly 6 - Mercury Control Field Demonstrations; Quarterly 7 - Mercury Regulations in the United States: Federal and State; and Quarterly 8 - Commercialization Aspects of Sorbent Injection Technologies in Canada. In this last of nine quarterly reports, an update of these mercury issues is presented that includes a summary of each topic, with recent information pertinent to advances made since the quarterly reports were originally presented. In addition to a comprehensive update of previous mercury-related topics, a review of results from the CEA Mercury Program is provided. 86 refs., 11 figs., 8 tabs.

  8. Human accumulation of mercury in Greenland

    DEFF Research Database (Denmark)

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

    2007-01-01

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

  9. Human accumulation of mercury in Greenland

    DEFF Research Database (Denmark)

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

    2007-01-01

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

  10. Mercury emission from crematories in Japan

    Directory of Open Access Journals (Sweden)

    M. Takaoka

    2010-04-01

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

  11. Global Mercury Pathways in the Arctic Ecosystem

    Science.gov (United States)

    Lahoutifard, N.; Lean, D.

    2003-12-01

    The sudden depletions of atmospheric mercury which occur during the Arctic spring are believed to involve oxidation of gaseous elemental mercury, Hg(0), rendering it less volatile and more soluble. The Hg(II) oxidation product(s) are more susceptible to deposition, consistent with the observation of dramatic increases in snow mercury levels during depletion events. Temporal correlations with ozone depletion events and the proliferation of BrO radicals support the hypothesis that oxidation of Hg(0) occurs in the gas phase and results in its conversion to RGM (Reactive Gaseous Mercury). The mechanisms of Hg(0) oxidation and particularly Hg(II) reduction are as yet unproven. In order to evaluate the feasibility of proposed chemical processes involving mercury in the Arctic atmosphere and its pathway after deposition on the snow from the air, we investigated mercury speciation in air and snow pack at Resolute, Nunavut, Canada (latitude 75° N) prior to and during snow melt during spring 2003. Quantitative, real-time information on emission, air transport and deposition were combined with experimental studies of the distribution and concentrations of different mercury species, methyl mercury, anions, total organic carbon and total inorganic carbon in snow samples. The effect of solar radiation and photoreductants on mercury in snow samples was also investigated. In this work, we quantify mercury removed from the air, and deposited on the snow and the transformation to inorganic and methyl mercury.

  12. Comparative analysis of mercury content in human hair and ...

    African Journals Online (AJOL)

    Total mercury (T-Hg) concentrations were analysed in human hairs and cosmetic products sold in Dar es Salaam Tanzania. The average total mercury (T-Hg) concentrations in the scalp hair of females using mercury based cosmetic creams and soaps ranged from 7.0 ± 0.4 to 880 ± 12 ppm. Highest T-Hg concentrations ...

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

    Science.gov (United States)

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

    2012-12-01

    Marine fish and shellfish are the main source of toxic methylmercury exposure for humans. As recently as decade ago, very limited aqueous methylated mercury data were available from marine settings, resulting in a generally poor understanding of the processes controlling mercury in pelagic marine food webs. Recent oceanographic cruises have significantly improved availability of reliable measurements of methylated mercury and total mercury in seawater. This presentation will focus on vertical seawater profiles collected to depths 1000 m from three recent sampling efforts in collaboration with the CLIVAR Repeat Hydrography Program sponsored by NOAA including: 1) the northeastern Pacific (P16N cruise from Honolulu, Hawaii to Kodiak, Alaska); (2) the southern Indian Ocean (I5 cruise from Cape Town, South Africa, to Fremantle, Australia); and, (3) the Southern Ocean cruise (S4P from McMurdo, Antarctica, to Punta Arenas, Chile). Analytical results presented were all derived from the USGS Mercury Research Lab (http://wi.water.usgs.gov/mercury-lab). Supporting data derived from these cruises on water mass ages, nutrients, carbon and dissolved oxygen provide an opportunity to develop a stronger understanding of the biogeochemical factors controlling oceanic distributions of mercury and methylated mercury. Whole-water, median total mercury, and methylated mercury concentrations for the northern Pacific, southern Indian, and Southern Ocean were 1.10, 0.80, and 1.65 pM, , and 0.11, 0.08, and 0.32 pM, respectively. For all three oceans, vertical profiles of total mercury generally show the lowest concentrations in the surface mixed layer, and concentration maxima at the 700-1000 m depths. Surface depletion of total mercury is attributed to photo-chemical reduction and evasion of gaseous elemental mercury as well as scavenging by settling particulate matter, the main vector of transport to the subsurface ocean. Methylated mercury in all the ocean profiles reveal distinct mid

  14. What are the Connections between Mercury and CFLs?

    Science.gov (United States)

    Small amounts of mercury vapor can be released when CFLs break or are improperly disposed of. Despite these emissions, the use of CFLs actually helps reduce total mercury emissions in the U.S. because of their significant energy savings.

  15. Application of neutron activation analysis to the determination of total mercury and other elements of interest in soil and sediment samples from Serra do Navio and Vila Nova River Basin, Amapa, Brazil

    International Nuclear Information System (INIS)

    Goncalves, Cristina

    1997-01-01

    In this work it is presented a survey on total mercury determination by a radiochemical method in sediment and soil samples from two regions, in the state of Amapa: Serra do Navio (background area) and Vila Nova river basin (gold mining area). The method consisted in leaching of the irradiated samples with acqua regia in a Parr bomb, and heating in microwave oven, for one minute. Then the solvent extraction technique was applied, using bismuth diethyldithiocarbamate (Bi(DDC) 3 ) as extractant agent. The organic phase, containing 197 Hg and 203 Hg radioisotopes, was measured in a gamma spectrometer with hyper pure Ge detector. This method eliminated the interference of the 279.54 keV photopeak of 75 Se on 279.2 keV photopeak of 203 Hg, besides improving counting statistics of both Hg radioisotopes. The elements As, Ba, Br, Ce, Co, Cr, Cs, Eu, Fe, Hf, Ho, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, Ti, U, V, W, Yb, Zn and Zr were also determined by the instrumental neutron activation analysis. Two irradiation series were carried out to quantify these elements in soil and sediment samples; a short term irradiation allowed to evaluate Mg, Mn, Na, Ti and V levels, and by long term irradiation, the other elements were determined. Precision and accuracy of radiochemical procedure were verified by means of analysis of the reference materials Buffalo River Sediment and Lake Sediment, for sediments and GXR-5, for soils. For the instrumental analysis, the reference materials Buffalo River Sediment, Soil 7, JB-1 and Oyster Tissue were used. The samples were also submitted to X ray diffraction, in Instituto de Geoscience-USP, to observe mercury behaviour with mineralogy. Aluminium concentration was determined by X ray fluorescence method, in the Department of Materials, IPEN/CNEN-SP, making possible enrichment factor calculation so that mercurial contamination in the gold mining area (Vila Nova river basin) could be evaluated. The mercury levels obtained in this

  16. Mercury kinetics in marine zooplankton

    International Nuclear Information System (INIS)

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

    1976-01-01

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

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

    Directory of Open Access Journals (Sweden)

    J. Wang

    2013-10-01

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

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

    Directory of Open Access Journals (Sweden)

    J Wang

    2013-10-01

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

  19. Mercury's Messenger

    Science.gov (United States)

    Chapman, Clark R.

    2004-01-01

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

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

    Science.gov (United States)

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

  1. Mercury Information Clearinghouse

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-03-31

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

  2. Distribution and variability of total mercury in snow cover-a case study from a semi-urban site in Poznań, Poland.

    Science.gov (United States)

    Siudek, Patrycja

    2016-12-01

    In the present paper, the inter-seasonal Hg variability in snow cover was examined based on multivariate statistical analysis of chemical and meteorological data. Samples of freshly fallen snow cover were collected at the semi-urban site in Poznań (central Poland), during 3-month field measurements in winter 2013. It was showed that concentrations of atmospherically deposited Hg were highly variable in snow cover, from 0.43 to 12.5 ng L -1 , with a mean value of 4.62 ng L -1 . The highest Hg concentration in snow cover coincided with local intensification of fossil fuel burning, indicating large contribution from various anthropogenic sources such as commercial and domestic heating, power generation plants, and traffic-related pollution. Moreover, the variability of Hg in collected snow samples was associated with long-range transport of pollutants, nocturnal inversion layer, low boundary layer height, and relatively low air temperature. For three snow episodes, Hg concentration in snow cover was attributed to southerly advection, suggesting significant contribution from the highly polluted region of Poland (Upper Silesia) and major European industrial hotspots. However, the peak Hg concentration was measured in samples collected during predominant N to NE advection of polluted air masses and after a relatively longer period without precipitation. Such significant contribution to the higher Hg accumulation in snow cover was associated with intensive emission from anthropogenic sources (coal combustion) and atmospheric conditions in this area. These results suggest that further measurements are needed to determine how the Hg transformation paths in snow cover change in response to longer/shorter duration of snow cover occurrence and to determine the interactions between mercury and absorbing carbonaceous aerosols in the light of climate change.

  3. Biosensors for detection of mercury in contaminated soils

    International Nuclear Information System (INIS)

    Bontidean, Ibolya; Mortari, Alessia; Leth, Suzanne; Brown, Nigel L.; Karlson, Ulrich; Larsen, Martin M.; Vangronsveld, Jaco; Corbisier, Philippe; Csoeregi, Elisabeth

    2004-01-01

    Biosensors based on whole bacterial cells and on bacterial heavy metal binding protein were used to determine the mercury concentration in soil. The soil samples were collected in a vegetable garden accidentally contaminated with elemental mercury 25 years earlier. Bioavailable mercury was measured using different sensors: a protein-based biosensor, a whole bacterial cell based biosensor, and a plant sensor, i.e. morphological and biochemical responses in primary leaves and roots of bean seedlings grown in the mercury-contaminated soil. For comparison the total mercury concentration of the soil samples was determined by AAS. Whole bacterial cell and protein-based biosensors gave accurate responses proportional to the total amount of mercury in the soil samples. On the contrary, plant sensors were found to be less useful indicators of soil mercury contamination, as determined by plant biomass, mercury content of primary leaves and enzyme activities

  4. Mercury emissions from municipal solid waste combustors

    Energy Technology Data Exchange (ETDEWEB)

    1993-05-01

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

  5. Mercury bioaccumulation in Southern Appalachian birds, assessed through feather concentrations

    Science.gov (United States)

    Rebecca Hylton Keller; Lingtian Xie; David B. Buchwalter; Kathleen E. Franzreb; Theodore R Simons

    2014-01-01

    Mercury contamination in wildlife has rarely been studied in the Southern Appalachians despite high deposition rates in the region. From 2006 to 2008 we sampled feathers from 458 birds representing 32 species in the Southern Appalachians for total mercury and stable isotope ä 15N. Mercury concentrations (mean ± SE) averaged 0.46...

  6. Determination of methylmercury and estimation of total mercury in seafood using high performance liquid chromatography (HPLC) and inductively coupled plasma-mass spectrometry (ICP-MS): Method development and validation

    Energy Technology Data Exchange (ETDEWEB)

    Hight, Susan C. [Elemental Research Branch, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, 5100 Paint Branch Parkway, College Park, MD 20740-3835 (United States)]. E-mail: susan.hight@fda.gov; Cheng, John [Elemental Research Branch, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, 5100 Paint Branch Parkway, College Park, MD 20740-3835 (United States)]. E-mail: john.cheng@fda.gov

    2006-05-17

    A method was developed for determination of methylmercury and estimation of total mercury in seafood. Mercury (Hg) compounds were extracted from 0.5 g edible seafood or 0.2 g lyophilized reference material by adding 50 ml aqueous 1% w/v L-cysteine.HCl.H{sub 2}O and heating 120 min at 60 deg. C in glass vials. Hg compounds in 50 {mu}l of filtered extract were separated by reversed-phase high performance liquid chromatography using a C-18 column and aqueous 0.1% w/v L-cysteine.HCl.H{sub 2}O + 0.1% w/v L-cysteine mobile phase at room temperature and were detected by inductively coupled plasma-mass spectrometry at mass-to-charge ratio 202. Total Hg was calculated as the mathematical sum of methyl and inorganic Hg determined in extracts. For seafoods containing 0.055-2.78 mg kg{sup -1} methylmercury and 0.014-0.137 mg kg{sup -1} inorganic Hg, precision of analyses was {<=}5% relative standard deviation (R.S.D.) for methylmercury and {<=}9% R.S.D. for inorganic Hg. Recovery of added analyte was 94% for methylmercury and 98% for inorganic Hg. Methyl and total Hg results for reference materials agreed with certified values. Limits of quantitation were 0.007 mg kg{sup -1} methylmercury and 0.005 mg kg{sup -1} inorganic Hg in edible seafood and 0.017 mg kg{sup -1} methylmercury and 0.012 mg kg{sup -1} inorganic Hg in lyophilized reference materials. Evaluation of analyte stability demonstrated that L-cysteine both stabilized and de-alkylated methylmercury, depending on holding time and cysteine concentration. Polypropylene adversely affected methylmercury stability. Total Hg results determined by this method were equivalent to results determined independently by cold vapour-atomic absorption spectrometry. Methylmercury was the predominant form of Hg in finfish. Ratios of methylmercury/total Hg determined by this method were 93-98% for finfish and 38-48% for mollusks.

  7. Mercury species in formerly contaminated soils and released soil gases

    Czech Academy of Sciences Publication Activity Database

    Sysalová, J.; Kučera, Jan; Drtinová, B.; Červenka, R.; Zvěřina, O.; Komárek, J.; Kameník, Jan

    2017-01-01

    Roč. 584, APR (2017), s. 1032-1039 ISSN 0048-9697 R&D Projects: GA ČR(CZ) GBP108/12/G108; GA MŠk LM2015056 Institutional support: RVO:61389005 Keywords : mercury contaminated soils * total mercury * elemental mercury * methylmercury * phynelmercury * gaseous elemental mercury Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 4.900, year: 2016

  8. Methyl mercury, but not inorganic mercury, associated with higher blood pressure during pregnancy.

    Science.gov (United States)

    Wells, Ellen M; Herbstman, Julie B; Lin, Yu Hong; Hibbeln, Joseph R; Halden, Rolf U; Witter, Frank R; Goldman, Lynn R

    2017-04-01

    Prior studies addressing associations between mercury and blood pressure have produced inconsistent findings; some of this may result from measuring total instead of speciated mercury. This cross-sectional study of 263 pregnant women assessed total mercury, speciated mercury, selenium, and n-3 polyunsaturated fatty acids in umbilical cord blood and blood pressure during labor and delivery. Models with a) total mercury or b) methyl and inorganic mercury were evaluated. Regression models adjusted for maternal age, race/ethnicity, prepregnancy body mass index, neighborhood income, parity, smoking, n-3 fatty acids and selenium. Geometric mean total, methyl, and inorganic mercury concentrations were 1.40µg/L (95% confidence interval: 1.29, 1.52); 0.95µg/L (0.84, 1.07); and 0.13µg/L (0.10, 0.17), respectively. Elevated systolic BP, diastolic BP, and pulse pressure were found, respectively, in 11.4%, 6.8%, and 19.8% of mothers. In adjusted multivariable models, a one-tertile increase of methyl mercury was associated with 2.83mmHg (0.17, 5.50) higher systolic blood pressure and 2.99mmHg (0.91, 5.08) higher pulse pressure. In the same models, an increase of one tertile of inorganic mercury was associated with -1.18mmHg (-3.72, 1.35) lower systolic blood pressure and -2.51mmHg (-4.49, -0.53) lower pulse pressure. No associations were observed with diastolic pressure. There was a non-significant trend of higher total mercury with higher systolic blood pressure. We observed a significant association of higher methyl mercury with higher systolic and pulse pressure, yet higher inorganic mercury was significantly associated with lower pulse pressure. These results should be confirmed with larger, longitudinal studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Evaluating the spatial variation of total mercury in young-of-year yellow perch (Perca flavescens), surface water and upland soil for watershed-lake systems within the southern Boreal Shield

    Science.gov (United States)

    Gabriel, M.C.; Kolka, R.; Wickman, T.; Nater, E.; Woodruff, Laurel G.

    2009-01-01

    The primary objective of this research is to investigate relationships between mercury in upland soil, lake water and fish tissue and explore the cause for the observed spatial variation of THg in age one yellow perch (Perca flavescens) for ten lakes within the Superior National Forest. Spatial relationships between yellow perch THg tissue concentration and a total of 45 watershed and water chemistry parameters were evaluated for two separate years: 2005 and 2006. Results show agreement with other studies where watershed area, lake water pH, nutrient levels (specifically dissolved NO3−-N) and dissolved iron are important factors controlling and/or predicting fish THg level. Exceeding all was the strong dependence of yellow perch THg level on soil A-horizon THg and, in particular, soil O-horizon THg concentrations (Spearman ρ = 0.81). Soil B-horizon THg concentration was significantly correlated (Pearson r = 0.75) with lake water THg concentration. Lakes surrounded by a greater percentage of shrub wetlands (peatlands) had higher fish tissue THg levels, thus it is highly possible that these wetlands are main locations for mercury methylation. Stepwise regression was used to develop empirical models for the purpose of predicting the spatial variation in yellow perch THg over the studied region. The 2005 regression model demonstrates it is possible to obtain good prediction (up to 60% variance description) of resident yellow perch THg level using upland soil O-horizon THg as the only independent variable. The 2006 model shows even greater prediction (r2 = 0.73, with an overall 10 ng/g [tissue, wet weight] margin of error), using lake water dissolved iron and watershed area as the only model independent variables. The developed regression models in this study can help with interpreting THg concentrations in low trophic level fish species for untested lakes of the greater Superior National Forest and surrounding Boreal ecosystem.

  10. Mercury in products - a source of transboundary pollutant transport

    Energy Technology Data Exchange (ETDEWEB)

    Munthe, J; Kindbom, K [Swedish Environmental Research Inst., Stockholm (Sweden)

    1997-12-01

    The purpose of this report is to summarize current knowledge on product-related emissions of mercury to air on a European scale, and to estimate the contribution from mercury contained in products, to the total anthropogenic emissions of mercury to air and transboundary transport of mercury in Europe. Products included in this study are batteries, measuring and control instruments, light sources and electrical equipment, all intentionally containing mercury. The main result of this study is that product-related emission of mercury can contribute significantly to total emissions and transboundary transport of mercury in the European region and that measures to limit the use of mercury in products can contribute to an overall decrease of the environmental input of mercury in Europe. It is concluded that: -Mercury contained in products may be emitted to air during consumption, after disposal when incinerated or when volatilized from landfill. Mercury may also be emitted to air during recycling of scrap metal or when accumulated (stored) in society. -The amount of mercury consumed in batteries and in measuring and control instruments had decreased since the late 1980`s. The total use of mercury in light sources and electrical equipment has not changed significantly during the same time period. The contribution to total anthropogenic emissions of mercury to air in Europe in the mid 1990`s is estimated to be: for batteries 4%; for measuring and control instruments 3%; for lighting and electrical equipment 11%. -Mercury in products leads to significant wet deposition input in Scandinavia. The relative amount of the total deposition flux attributable to products is estimated to be 10-14% 26 refs, 4 figs, 10 tabs

  11. EDITORIAL: Mercury-free discharges for lighting

    Science.gov (United States)

    Haverlag, M.

    2007-07-01

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

  12. Assessment of Dietary Mercury Intake and Blood Mercury Levels in the Korean Population: Results from the Korean National Environmental Health Survey 2012–2014

    Directory of Open Access Journals (Sweden)

    Seong-Ah Kim

    2016-09-01

    Full Text Available From a public health perspective, there is growing concern about dietary mercury intake as the most important source of mercury exposure. This study was performed to estimate dietary mercury exposure and to analyze the association between mercury intake and blood mercury levels in Koreans. The study subjects were 553 adults, comprising a 10% representative subsample of the Korean National Environmental Health Survey (KoNEHS 2012–2014, who completed a health examination, a face-to-face interview, and a three-day food record. Dietary mercury and methylmercury intakes were assessed from the three-day food record, and blood mercury concentration was measured using a mercury analyzer. The association between dietary mercury intake and blood mercury levels was analyzed by comparing the odds ratios for the blood mercury levels above the Human BioMonitoring (HBM I value (5 μg/L among the three groups with different mercury intakes. The average total mercury intake was 4.74 and 3.07 μg/day in males and females, respectively. The food group that contributed most to mercury intake was fish and shellfish, accounting for 77.8% of total intake. The geometric mean of the blood mercury concentration significantly and linearly increased with the mercury and methylmercury intakes (p < 0.001. The odds ratios for blood mercury levels above the HBM I value in the highest mercury and methyl mercury intake group were 3.27 (95% Confidence Interval (CI 1.79–5.95 and 3.20 (95% CI 1.77–5.79 times higher than that of the lowest intake group, respectively. Our results provide compelling evidence that blood mercury level has a strong positive association with dietary intake, and that fish and shellfish contribute most to the dietary mercury exposure.

  13. Assessment of Dietary Mercury Intake and Blood Mercury Levels in the Korean Population: Results from the Korean National Environmental Health Survey 2012–2014

    Science.gov (United States)

    Kim, Seong-Ah; Kwon, YoungMin; Kim, Suejin; Joung, Hyojee

    2016-01-01

    From a public health perspective, there is growing concern about dietary mercury intake as the most important source of mercury exposure. This study was performed to estimate dietary mercury exposure and to analyze the association between mercury intake and blood mercury levels in Koreans. The study subjects were 553 adults, comprising a 10% representative subsample of the Korean National Environmental Health Survey (KoNEHS) 2012–2014, who completed a health examination, a face-to-face interview, and a three-day food record. Dietary mercury and methylmercury intakes were assessed from the three-day food record, and blood mercury concentration was measured using a mercury analyzer. The association between dietary mercury intake and blood mercury levels was analyzed by comparing the odds ratios for the blood mercury levels above the Human BioMonitoring (HBM) I value (5 μg/L) among the three groups with different mercury intakes. The average total mercury intake was 4.74 and 3.07 μg/day in males and females, respectively. The food group that contributed most to mercury intake was fish and shellfish, accounting for 77.8% of total intake. The geometric mean of the blood mercury concentration significantly and linearly increased with the mercury and methylmercury intakes (p mercury levels above the HBM I value in the highest mercury and methyl mercury intake group were 3.27 (95% Confidence Interval (CI) 1.79–5.95) and 3.20 (95% CI 1.77–5.79) times higher than that of the lowest intake group, respectively. Our results provide compelling evidence that blood mercury level has a strong positive association with dietary intake, and that fish and shellfish contribute most to the dietary mercury exposure. PMID:27598185

  14. Mercury contamination extraction

    Science.gov (United States)

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

    2009-09-15

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

  15. Mercury distribution in Douro estuary (Portugal)

    Energy Technology Data Exchange (ETDEWEB)

    Ramalhosa, E. [Department of Chemistry, University of Aveiro, 3810-193 Aveiro (Portugal); Pereira, E. [Department of Chemistry, University of Aveiro, 3810-193 Aveiro (Portugal)]. E-mail: eduper@dq.ua.pt; Vale, C. [National Institute for Agronomy and Fishery Research, IPIMAR, Avenida Brasilia, 1449-006 Lisboa (Portugal); Valega, M. [Department of Chemistry, University of Aveiro, 3810-193 Aveiro (Portugal); Monterroso, P. [Department of Chemistry, University of Aveiro, 3810-193 Aveiro (Portugal); Duarte, A.C. [Department of Chemistry, University of Aveiro, 3810-193 Aveiro (Portugal)

    2005-11-15

    Determinations of dissolved reactive and total dissolved mercury, particulate and sedimentary mercury, dissolved organic carbon (DOC), particulate organic carbon (POC) and suspended particulate matter (SPM) have been made in the estuary of river Douro, in northern Portugal. The estuary was stratified by salinity along most of its length, it had low concentrations of SPM, typically <20 mg dm{sup -3}, and concentrations of DOC in the range <1.0-1.8 mg dm{sup -3}. The surface waters had a maximum dissolved concentration of reactive mercury of about 10 ng dm{sup -3}, whereas for the more saline bottom waters it was about 65 ng dm{sup -3}. The surface waters had maximum concentrations of total suspended particulate mercury of {approx}7 {mu}g g{sup -1} and the bottom waters were always <1 {mu}g g{sup -1}. Concentrations of mercury in sediments was low and in the range from 0.06 to 0.18 {mu}g g{sup -1}. The transport of mercury in surface waters was mainly associated with organic-rich particulate matter, while in bottom waters the dissolved phase transport of mercury is more important. Lower particulate organic matter, formation of chlorocomplexes in more saline waters and eventually the presence of colloids appear to explain the difference of mercury partitioning in Douro estuarine waters.

  16. Comparative study of nutritional constituents and the mercury total constituents in fishes commercialized at the city of Cananeia, at the coastal of Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Nascimento, Soraia M.; Farias, Luciana A.; Curcho, Michel R.M.; Favaro, Deborah I.T.; Braga, Elisabete S.

    2009-01-01

    Aiming the determination of the Hg concentration and the As, Cr and Zn trace elements, four commercial available and frequently consumable fishes by the Cananeia, Sao Paulo, Brazil, were analysed. A total of 53 samples were evaluated as follows: jew fish (Micropogonias furnieri), hake (Macrodon ancylodon), perch (Centropomus undecimalis), and grey mullet (Mugil platanus), all acquired at local fishmonger. The atomic absorption and neutron activation analysis techniques were used for the determination of Hg total levels and trace elements respectively. The trace elements presented large concentration variation among the same specie and the species performed as well. The jew fish presented levels superior to 1000 μg kg -1 for the most individuals analysed and the perch presented chromium levels exceeding the limit of 0.10 mg kg -1 for some individuals. The level of Zn presented values below 50 mg kg -1 established by the Brazilian legislation for all species. The Zn total contents among all species presented values bellow the limits of the Brazilian legislation (500 μg kg -1 for the predator species and 1000 μg kg -1 for the predator species)

  17. Worldwide trend of atmospheric mercury since 1995

    Directory of Open Access Journals (Sweden)

    F. Slemr

    2011-05-01

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

  18. Chemometrics methods for the investigation of methylmercury and total mercury contamination in mollusks samples collected from coastal sites along the Chinese Bohai Sea.

    Science.gov (United States)

    Yawei, Wang; Lina, Liang; Jianbo, Shi; Guibin, Jiang

    2005-06-01

    The development and application of chemometrics methods, principal component analysis (PCA), cluster analysis and correlation analysis for the determination of methylmercury (MeHg) and total mecury (HgT) in gastropod and bivalve species collected from eight coastal sites along the Chinese Bohai Sea are described. HgT is directly determined by atomic fluorescence spectrometry (AFS), while MeHg is measured by a laboratory established high performance liquid chromatography-atomic fluorescence spectrometry system (HPLC-AFS). One-way ANOVA and cluster analysis indicated that the bioaccumulation of Rap to accumulate Hg was significantly (P<0.05) different from other mollusks. Correlation analysis shows that there is linear relationship between MeHg and HgT in mollusks samples collected from coastal sites along the Chinese Bohai Sea, while in mollusks samples collected from Hongqiao market in Beijing City, there is not any linear relationship.

  19. Mercúrio total em solos de manguezais da Baixada Santista e Ilha do Cardoso, estado de São Paulo Total mercury in mangrove soils of the Baixada Santista and Cardoso Island, São Paulo state

    Directory of Open Access Journals (Sweden)

    Mara Lucia Jacinto Oliveira

    2007-06-01

    Full Text Available Total Hg content in soils of Baixada Santista, affected by different sources of pollution, and Cardoso Island, which is almost free of anthropogenic activities, were determined by CVAAS. To explain the fate of Hg in the ecosystem, pH, Eh, AVS, Stotal and Total Organic Carbon were also obtained throughout the soil profiles. With the exception of two sampling sites the average content of Hg in samples obtained for Baixada Santista was 0.34 ± 0.20 mg kg-1, which was close to the average data at Cardoso Island (0.30 ± 0.21 mg kg-1. Both of them were below the limit established by CETESB - 0.50 mg kg-1.

  20. Searching for the Source of Salt Marsh Buried Mercury.

    Science.gov (United States)

    Brooke, C. G.; Nelson, D. C.; Fleming, E. J.

    2016-12-01

    Salt marshes provide a barrier between upstream mercury contamination and coastal ecosystems. Mercury is sorbed, transported, and deposited in estuarine systems. Once the upstream mercury source has been remediated, the downstream mercury contaminated salt marsh sediments should become "capped" or buried by uncontaminated sediments preventing further ecosystem contamination. Downstream from a remediated mercury mine, an estuarine intertidal marsh in Tomales Bay, CA, USA, scavengers/predators (e.g. Pachygrapsus crassipes, Lined Shore Crab) have leg mercury concentrations as high as 5.5 ppm (dry wt./dry wt.), which increase significantly with crab size, a surrogate for trophic level. These elevated mercury concentrations suggests that "buried" mercury is rereleased into the environment. To locate possible sources of mercury release in Walker Marsh, we sampled a transect across the marsh that included diverse micro-environments (e.g. rhizoshere, stratified sediments, faunal burrows). From each location we determined the sediment structure, sediment color, total sediment mercury, total sediment iron, and microbial composition (n = 28). Where flora or fauna had perturbed the sediment, mercury concentrations were 10% less than undisturbed stratified sediments (1025 ppb vs. 1164 ppb, respectively). High-throughput SSU rRNA gene sequencing and subsequent co-occurrence network analysis genera indicated that in flora- or fauna- perturbed sediments there was an increased likelihood that microbial genera contained mercury mobilizing genes (94% vs 57%; in perturbed vs stratified sediments, respectively). Our observations are consistent with findings by others that in perturbed sites mercury mobility increased. We did however identify a microbial and geochemical profile with increased mercury mobility. For future work we plan to quantify the role these micro-environments have on mercury-efflux from salt marshes.

  1. Anthropogenic mercury deposition to arctic lake sediments

    Energy Technology Data Exchange (ETDEWEB)

    Hermanson, M.H. [Westchester University, Westchester, PA (United States). Dept. of Health

    1998-01-01

    The history of atmospheric mercury inputs to remote arctic regions can be measured in lake sediment cores using lead-210 chronology. In the investigation, total mercury deposition is measured in sediments from Imitavik and Annak Lakes on the Belcher Islands in southeastern Hudson Bay, an area in the southern Canadian Arctic with no history of local industrial or agricultural sources of contamination. Both lakes received background and atmospheric inputs of mercury while Annak also received mercury from raw domestic sewage from the Hamlet of Sanikiluaq, a growing Inuit community of about 550 established in the late 1960s. Results from Imitavik show that anthropogenic mercury inputs, apparently transported through the atmosphere, began to appear in the mid-eighteenth century, and continued to the 1990s. Annak had a similar mercury history until the late 1960s when disposal of domestic sewage led to increased sediment and contaminant accumulation. The high input of mercury to Annak confirms that Sanikiluaq residents are exposed to mercury through native food sources. 39 refs., 7 figs., 3 tabs.

  2. Avaliação da contaminação mercurial mediante análise do teor de Hg total em amostras de cabelo em comunidades ribeirinhas do Tapajós, Pará, Brasil

    Directory of Open Access Journals (Sweden)

    Pinheiro Maria da Conceição Nascimento

    2000-01-01

    Full Text Available Este estudo avalia a contaminação mercurial em comunidades de pescadores em quatro localidades nas margens do rio Tapajós: Rainha, Barreiras, São Luís do Tapajós e Paraná-Mirim. Análises toxocológicas das amostras de cabelo foram realizadas por espectofotometria de absorção atômica. Os níveis de mercúrio total em amostras de cabelo variaram entre 2,9µg/g e 71,5µg/g. Os valores mais baixos foram encontrados na comunidade de Paraná-Mirim. Os mais elevados, em São Luís do Tapajós e Barreiras, cerca de seis a sete vezes superiores ao valor estabelecido. As diferenças entre as concentrações médias de mercúrio total nas amostras, coletadas em populações ribeirinhas, a montante e a jusante do rio Tapajós em Itaituba, não apresentaram significância estatística (p > 0,05. Conclui-se que a exposição humana ao mercúrio por ingestão de peixes contaminados constitui risco potencial para o aparecimento de sintomas e sinais da doença de Minamata, o que recomenda a manutenção de um programa de vigilância epidemiológica.

  3. Global Trends in Mercury Management

    Science.gov (United States)

    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

  4. Atmospheric mercury in Changbai Mountain area, northeastern China II. The distribution of reactive gaseous mercury and particulate mercury and mercury deposition fluxes.

    Science.gov (United States)

    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.

  5. Distribution and excretion of inhaled mercury vapour

    Energy Technology Data Exchange (ETDEWEB)

    Gage, J C

    1961-01-01

    Rats have been exposed for varying periods to an atmosphere containing 1 mg/cu.m. mercury vapor. The toxic effects produced showed resemblances to signs of mercurialism in man. An attempt has been made to study the kinetics of absorption and excretion of mercury from measurements of the amounts excreted and stored in the tissues. The efficiency of absorption of mercury by the rat lung is about 50%. A small proportion is excreted into the gut. After about 10 days of continuous exposure a steady state is reached in which excretion balances absorption. During short exposures the turnover of mercury in all tissues except brain is fairly rapid and most of the mercury is cleared from the body within a week after exposure. The urinary excretion of mercury, during the initial stage of storage in the tissues and the final stage of clearance, shows divergencies from the simple exponential pattern; there appears to be a delay mechanism in the kidney which, in intermittent exposures, may result in the occurrence of peak excretion during periods of non-exposure. After more prolonged exposures the mercury in the kidney appears to be converted to a form which is only very slowly excreted. The significance of the urinary excretion of mercury by man after industrial exposure to mercury vapour is discussed. The rat experiments suggest that single measurements will give only limited information concerning industrial conditions, but that an approximate assessment of the total absorbed during a working week would be obtained if it were possible to make a seven-day collection of urine. Repeated measurements after exposure would yield information on the duration of exposure and would have some diagnostic value.

  6. Basic Information about Mercury

    Science.gov (United States)

    ... or metallic mercury is a shiny, silver-white metal and is liquid at room temperature. It is ... releases can happen naturally. Both volcanoes and forest fires send mercury into the atmosphere. Human activities, however, ...

  7. Minamata Convention on Mercury

    Science.gov (United States)

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

  8. Mercury accumulation in native mammals of the Southeast

    Energy Technology Data Exchange (ETDEWEB)

    Cumbie, P.M.; Jenkins, J.H.

    1974-01-01

    Mercury levels in tissues of mammals collected in Georgia, Florida, and South Carolina were compared using hair mercury concentration as an index of total mercury content. Bobcats (Lynx rufus), raccoons (Procyon lotor), opossum (Didelphis marsupialis) and gray fox (Urocyon cinereoargenteus) from the Lower Coastal Plain of Georgia had higher mercury levels than specimens from the Upper Coastal Plain or Piedmont. The highest individual mercury levels in raccoons and bobcats occurred in specimens from the Georgia Lower Coastal Plain flatwoods. Skeletal muscle and liver of individual raccoons and bobcats taken in the coastal flatwoods exceeded the 0.5 ppm limit for mercury in human foodstuffs. No pattern of mercury accumulation was detected in white-tailed deer (Odocoileus virginianus). Hair analysis revealed elevated mercury levels in mammals from a region exposed to mercury pollution. Mercury levels in wildlife exhibit a pattern similar to that of certain fallout radioisotopes such as /sub 137/Cs. These observations indicate that significant biomagnification of mercury may occur in native mammals in certain southeastern habitats. 28 references, 6 tables.

  9. Mercury in Your Environment

    Science.gov (United States)

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

  10. Intoxication with metallic mercury

    International Nuclear Information System (INIS)

    Fichte, B.; Assmann, H.; Ritzau, F.

    1984-01-01

    Intoxications by metallic mercury are extremely rare. Report of a patient, who tried to commit suicide by subcutaneous injection of 500 g of metallic mercury. He died 16 months later in the course of the intoxication. A short review is given of effects and reactions of metallic mercury in the human organism. (orig.) [de

  11. Intoxication with metallic mercury

    Energy Technology Data Exchange (ETDEWEB)

    Fichte, B.; Ritzau, F.; Assmann, H.

    1984-02-01

    Intoxications by metallic mercury are extremely rare. Report is given of a patient who tried to commit suicide by subcutaneous injection of 500 g of metallic mercury. He died 16 months later in the course of the intoxication. A short review is given of effects and reactions of metallic mercury in the human organism.

  12. Intoxication with metallic mercury

    Energy Technology Data Exchange (ETDEWEB)

    Fichte, B.; Assmann, H.; Ritzau, F.

    1984-02-01

    Intoxications by metallic mercury are extremely rare. Report is given of a patient, who tried to commit suicide by subcutaneous injection of 500 g of metallic mercury. He died 16 months later in the course of the intoxication. A short review is given of effects and reactions of metallic mercury in the human organism.

  13. Multi-model study of mercury dispersion in the atmosphere: vertical and interhemispheric distribution of mercury species

    Directory of Open Access Journals (Sweden)

    J. Bieser

    2017-06-01

    Full Text Available Atmospheric chemistry and transport of mercury play a key role in the global mercury cycle. However, there are still considerable knowledge gaps concerning the fate of mercury in the atmosphere. This is the second part of a model intercomparison study investigating the impact of atmospheric chemistry and emissions on mercury in the atmosphere. While the first study focused on ground-based observations of mercury concentration and deposition, here we investigate the vertical and interhemispheric distribution and speciation of mercury from the planetary boundary layer to the lower stratosphere. So far, there have been few model studies investigating the vertical distribution of mercury, mostly focusing on single aircraft campaigns. Here, we present a first comprehensive analysis based on various aircraft observations in Europe, North America, and on intercontinental flights. The investigated models proved to be able to reproduce the distribution of total and elemental mercury concentrations in the troposphere including interhemispheric trends. One key aspect of the study is the investigation of mercury oxidation in the troposphere. We found that different chemistry schemes were better at reproducing observed oxidized mercury patterns depending on altitude. High concentrations of oxidized mercury in the upper troposphere could be reproduced with oxidation by bromine while elevated concentrations in the lower troposphere were better reproduced by OH and ozone chemistry. However, the results were not always conclusive as the physical and chemical parameterizations in the chemistry transport models also proved to have a substantial impact on model results.

  14. Mercury and methylmercury intake estimation due to seafood products for the Catalonian population (Spain)

    OpenAIRE

    2009-01-01

    Abstract This study estimates mercury and methylmercury levels in fish and fishery products commercialized in the city of Barcelona from 2001 to 2007. Combining food levels data with the consumption data of 2158 people (as the median of two 24-hour-recall), the total Mercury intake of the Catalonian population was calculated. Mercury was detected in 32,8% of analyses samples. The general population average weekly intake of total mercury in Catalonian population was 0.783 ?g/k...

  15. Mercury Hair Concentration among Primary School Children in Malaysia

    Directory of Open Access Journals (Sweden)

    Nurul Izzah Abdul Samad

    2017-12-01

    Full Text Available The main concern regarding mercury exposure is the adverse health effect on the developing nervous system. The objective of this cross-sectional study was to determine hair mercury levels and their association with socio-demographic characteristics, complaints about mercury poisoning symptoms and the fish consumption pattern among children in Malaysia. A cross-sectional study was conducted among 215 school children aged 11 years old. Hair was collected from the children and the total mercury was analyzed using oxygen combustion–gold amalgamation atomic absorption spectrophotometry. Anthropometric data, a fish consumption questionnaire and mercury poisoning symptoms were collected during a personal interview. The mean hair mercury level among primary school children was 0.63 ± 0.59 µg/g with the geometric mean of 0.47 µg/g. A total of 14% of respondents had hair mercury levels above 1 µg/g. A multiple binary logistic regression analysis outlined that fish consumption of at least one meal per week increased the likelihood of having a high mercury level (odds ratio (OR 3.7, 95% confidence interval (CI 1.3–10.4. This study confirms the existence of a mercury burden among Malaysian children and the level is high compared to other regional studies. This study provides important baseline data regarding the mercury level among children in Malaysia.

  16. Mercury in the environment : a primer

    Energy Technology Data Exchange (ETDEWEB)

    Lourie, B; Glenn, W [ed.; Ogilvie, K; Everhardus, E; Friesen, K; Rae, S

    2003-06-01

    This report provides an overview of the occurrence and effects of mercury in the environment and its impacts on human health. Low levels of mercury occur naturally everywhere in the environment in plants, animals, rocks and air. Incidental emissions occur when natural mercury is released to the environment through human activity. In Canada, coal burning and metal processing are the two largest point sources of atmospheric mercury emissions. Energy facilities have the option to invest in expensive control technologies for coal plants, or they can generate electricity from alternative energy sources. Energy conservation, however, offers the greatest overall benefits for the environment and the public. Mercury can also be released when products containing mercury (such as electrical switches, thermostats, dental amalgam, and thermometers) are broken while in use, or when they are crushed in garbage trucks and dumped in landfills. Source separation is the best way to reduce waste-related emissions. Once mercury is released to the natural environment, it can be transported long distances through air or watercourses. It is volatile, therefore evaporates readily to the atmosphere where it may do one of three things: it may fall out near the point where it was emitted; it may be transported long distances to some point downwind; or, it may enter the global atmospheric mercury pool where it will circle the globe for a year or more within the Earth's major weather systems before being deposited. Data from Canada's National Pollutant Release Inventory indicates that mercury releases and transfers total 28,674 kg per year. The most critical component of the mercury cycle is the conversion of inorganic forms of mercury to the organic compound methylmercury which is more toxic to humans. Most concern about mercury focuses on lakes and other aquatic ecosystems. Fish in hydroelectric reservoirs have been found to contain elevated methylmercury levels because natural mercury in the

  17. Substance Flow Analysis of Mercury in China

    Science.gov (United States)

    Hui, L. M.; Wang, S.; Zhang, L.; Wang, F. Y.; Wu, Q. R.

    2015-12-01

    In previous studies, the emission of anthropogenic atmospheric Hg in China as well as single sector have been examined a lot. However, there might have been more Hg released as solid wastes rather than air. Hg stored in solid wastes may be released to air again when the solid wastes experience high temperature process or cause local pollution if the solid wastes are stacked casually for a long time. To trace the fate of Hg in China, this study developed the substance flow of Hg in 2010 covering all the sectors summarized in table 1. Below showed in Figure 1, the total Hg input is 2825t. The unintentional input of Hg, mined Hg, and recycled Hg account for 57%, 32% and 11% respectively. Figure 2 provides the detail information of substance flow of Hg. Byproducts from one sector may be used as raw materials of another, causing cross Hg flow between sectors. The Hg input of cement production is 303 t, of which 34% comes from coal and limestone, 33% comes from non-ferrous smelting, 23% comes from coal combustion, 7% comes from iron and steel production and 3% comes from mercury mining. Hg flowing to recycledHg production is 639 t, mainly from Hg contained in waste active carbon and mercuric chloride catalyst from VCM production and acid sludge from non-ferrous smelting. There are 20 t mercury flowing from spent mercury adding products to incineration. Figure1 and Figure 2 also show that 46% of the output Hg belongs to "Lagged release", which means this part of mercury might be released later. The "Lagged release" Hg includes 809 t Hg contained in stacked byproducts form coal combustion, non-ferrous smelting, iron and steel production, Al production, cement production and mercury mining, 161t Hg stored in the pipeline of VCM producing, 10 t Hg in fluorescent lamps that are in use and 314 t mercury stored in materials waiting to be handled with in recycled mercury plants. There is 112 t Hg stored in landfill and 129 t Hg exported abroad with the export of mercury adding

  18. Spatial Patterns of Mercury Bioaccumulation in the Upper Clark Fork River Basin, MT

    Science.gov (United States)

    Staats, M. F.; Langner, H.; Moore, J. N.

    2010-12-01

    The Upper Clark Fork River Basin (UCFRB) in Montana has a legacy of historic gold/silver mine waste that contributes large quantities of mercury into the watershed. Mercury bioaccumulation at higher levels of the aquatic food chain, such as the mercury concentration in the blood of pre-fledge osprey, exhibit an irregular spatial signature based on the location of the nests throughout the river basin. Here we identify regions with a high concentration of bioavailable mercury and the major factors that allow the mercury to bioaccumulate within trophic levels. This identification is based on the abundance of mercury sources and the potential for mercury methylation. To address the source term, we did a survey of total mercury in fine sediments along selected UCFRB reaches, along with the assessment of environmental river conditions (percentage of backwaters/wetlands, water temperature and pH, etc). In addition, we analyzed the mercury levels of a representative number of macroinvertebrates and fish from key locations. The concentration of total mercury in sediment, which varies from reach to reach (tributaries of the Clark Fork River, 5mg/kg) affects the concentration of mercury found at various trophic levels. However, reaches with a low supply of mine waste-derived mercury can also yield substantial concentrations of mercury in the biota, due to highly favorable conditions for mercury methylation. We identify that the major environmental factor that affects the methylation potential in the UCFRB is the proximity and connectivity of wetland areas to the river.

  19. Aerobic Mercury-resistant bacteria alter Mercury speciation and retention in the Tagus Estuary (Portugal).

    Science.gov (United States)

    Figueiredo, Neusa L; Canário, João; O'Driscoll, Nelson J; Duarte, Aida; Carvalho, Cristina

    2016-02-01

    Aerobic mercury-resistant bacteria were isolated from the sediments of two highly mercury-polluted areas of the Tagus Estuary (Barreiro and Cala do Norte) and one natural reserve area (Alcochete) in order to test their capacity to transform mercury. Bacterial species were identified using 16S rRNA amplification and sequencing techniques and the results indicate the prevalence of Bacillus sp. Resistance patterns to mercurial compounds were established by the determination of minimal inhibitory concentrations. Representative Hg-resistant bacteria were further tested for transformation pathways (reduction, volatilization and methylation) in cultures containing mercury chloride. Bacterial Hg-methylation was carried out by Vibrio fluvialis, Bacillus megaterium and Serratia marcescens that transformed 2-8% of total mercury into methylmercury in 48h. In addition, most of the HgR bacterial isolates showed Hg(2+)-reduction andHg(0)-volatilization resulting 6-50% mercury loss from the culture media. In summary, the results obtained under controlled laboratory conditions indicate that aerobic Hg-resistant bacteria from the Tagus Estuary significantly affect both the methylation and reduction of mercury and may have a dual face by providing a pathway for pollution dispersion while forming methylmercury, which is highly toxic for living organisms. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Accumulation factors of mercury by King Bolete Boletus edulis

    Science.gov (United States)

    Falandysz, J.; Frankowska, A.

    2003-05-01

    To understand pollution picture with mercury and to examine suitability of King Bolete Boletits edulis Bull.: Fr. as possible bioindicator the total mercurv concentrations were determined both in the fruiting bodies and underlying soil substrate collected from various regions of Poland. There were quite large spatial variations of mercury concentration and some seasonal also were noted. Mercury content of the caps exceeded that of stalks (p<0.05), Nvhile Hg BCF values varied between 9 and 40, and 4 and 40, respectively.

  1. Determinação de mercúrio total em amostras de água, sedimento e sólidos em suspensão de corpos aquáticos por espectrofotometria de absorção atômica com gerador de vapor a frio Determination of total mercury in water, sediments and solids in suspension in aquatic systems by cold vapor atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    José L. F. Vieira

    1996-06-01

    Full Text Available O emprego de mercúrio metálico nos processos de extração do ouro libera toneladas de mercúrio ao meio ambiente, provocando um aumento considerável nas concentrações presentes. Com a finalidade de prevenir a exposição humana a concentrações excessivas, o que poderá resultar em graves episódios de intoxicação mercurial, bem como avaliar a possibilidade de sedimentos tornarem-se fontes potenciais de contaminação para os seres vivos, é de fundamental importância a monitorização do mercúrio em diversos compartimentos ambientais. Efetuou-se a padronização de uma metodologia analítica para determinação de mercúrio total em amostras de água, sólidos em suspensão e sedimentos de corpos aquáticos para monitorização ambiental do xenobiótico. Posteriormente, foram analisadas amostras oriundas de regiões garimpeiras, com vistas a avaliar o desempenho do método em amostras reais e efetuar levantamento preliminar sobre a contaminação mercurial na área de estudo.The use of metallic mercury in the extraction and concentration of gold causes the discarding of tons of this metal in the environment, leading to a considerable increase in the natural levels of the same and the contamination of the surrounding areas. Thus it is extremely important to monitor the presence of this metal in various sectors of the environment with a view aiming to previnting human exposure to excessive concentrations which can result in serious episodes of mercury poisoning. It is also important to estimate the possibility of river sediments becoming potential sources of contamination of human beings. The determination of total mercury was undertaken by using cold vapor atomic absorption spectrometry. River waters, as well as sediments and suspended solids were used as samples for the standardization of the analytical procedure. Later on, this method was tested on samples originating in gold mining areas for the purpose of assessing its validity.

  2. Simultaneous determination of mercury and organic carbon using a direct mercury analyzer: Mercury profiles in sediment cores from oxbow lakes in the Mississippi Delta

    Science.gov (United States)

    Sediment cores from seasonal wetland and open water areas from six oxbow lakes in the Mississippi River alluvial flood plain were analyzed for total-mercury (Hg) using a direct mercury analyzer (DMA). In the process we evaluated the feasibility of simultaneously determining organic matter content by...

  3. Mercury pollution in Wuchuan mercury mining area, Guizhou, Southwestern China: the impacts from large scale and artisanal mercury mining.

    Science.gov (United States)

    Li, Ping; Feng, Xinbin; Qiu, Guangle; Shang, Lihai; Wang, Shaofeng

    2012-07-01

    To evaluate the environmental impacts from large scale mercury mining (LSMM) and artisanal mercury mining (AMM), total mercury (THg) and methyl mercury (MeHg) were determined in mine waste, ambient air, stream water and soil samples collected from Wuchuan mercury (Hg) mining area, Guizhou, Southwestern China. Mine wastes from both LSMM and AMM contained high THg concentrations, which are important Hg contamination sources to the local environment. Total gaseous mercury (TGM) concentrations in the ambient air near AMM furnaces were highly elevated, which indicated that AMM retorting is a major source of Hg emission. THg concentrations in the stream water varied from 43 to 2100 ng/L, where the elevated values were mainly found in the vicinity of AMM and mine waste heaps of LSMM. Surface soils were seriously contaminated with Hg, and land using types and organic matter played an important role in accumulation and transportation of Hg in soil. The results indicated heavy Hg contaminations in the study area, which were resulted from both LSMM and AMM. The areas impacted by LSMM were concentrated in the historical mining and smelting facilities, while Hg pollution resulted from AMM can be distributed anywhere in the Hg mining area. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Evaluating the spatial variation of total mercury in young-of-year yellow perch (Perca flavescens), surface water and upland soil for watershed-lake systems within the southern Boreal Shield

    Science.gov (United States)

    Mark C. Gabriel; Randy Kolka; Trent Wickman; Ed Nater; Laurel. Woodruff

    2009-01-01

    The primary objective of this research is to investigate relationships between mercury in upland soil, lake water and fish tissue and explore the cause for the observed spatial variation of THg in age one yellow perch (Perca flavescens) for ten lakes within the Superior National Forest. Spatial relationships between yellow perch THg tissue...

  5. Sediment processes and mercury transport in a frozen freshwater fluvial lake (Lake St. Louis, QC, Canada).

    Science.gov (United States)

    Canário, João; Poissant, Laurier; O'Driscoll, Nelson; Vale, Carlos; Pilote, Martin; Lean, David

    2009-04-01

    An open-bottom and a closed-bottom mesocosm were developed to investigate the release of mercury from sediments to the water column in a frozen freshwater lake. The mesoscosms were deployed in a hole in the ice and particulate mercury (Hg(P)) and total dissolved mercury (TDHg) were measured in sediments and in water column vertical profiles. In addition, dissolved gaseous mercury (DGM) in water and mercury water/airflux were quantified. Concentrations of TDHg, DGM, and mercury flux were all higher in the open-bottom mesocosm than in the closed-bottom mesocosm. In this paper we focus on the molecular diffusion of mercury from the sediment in comparison with the TDHg accumulation in the water column. We conclude that the molecular diffusion and sediment resuspension play a minor role in mercury release from sediments suggesting that solute release during ebullition is an important transport process for mercury in the lake.

  6. [Evaluation of the mercury accumulating capacity of pepper (Capsicum annuum)].

    Science.gov (United States)

    Pérez-Vargas, Híver M; Vidal-Durango, Jhon V; Marrugo-Negrete, José L

    2014-01-01

    To assess the mercury accumulating capacity in contaminated soils from the community of Mina Santa Cruz, in the south of the department of Bolívar, Colombia, of the pepper plant (Capsicum annuum), in order to establish the risk to the health of the consuming population. Samples were taken from tissues (roots, stems, and leaves) of pepper plants grown in two soils contaminated with mercury and a control soil during the first five months of growth to determine total mercury through cold vapor atomic absorption spectrometry. Total mercury was determined in the samples of pepper plant fruits consumed in Mina Santa Cruz. The mean concentrations of total mercury in the roots were higher than in stems and leaves. Accumulation in tissues was influenced by mercury levels in soil and the growth time of the plants. Mercury concentrations in fruits of pepper plant were lower than tolerable weekly intake provided by WHO. Percent of translocation of mercury to aerial parts of the plant were low in both control and contaminated soils. Despite low levels of mercury in this food, it is necessary to minimize the consumption of food contaminated with this metal.

  7. Dissolved gaseous mercury formation and mercury volatilization in intertidal sediments.

    Science.gov (United States)

    Cesário, Rute; Poissant, Laurier; Pilote, Martin; O'Driscoll, Nelson J; Mota, Ana M; Canário, João

    2017-12-15

    Intertidal sediments of Tagus estuary regularly experiences complex redistribution due to tidal forcing, which affects the cycling of mercury (Hg) between sediments and the water column. This study quantifies total mercury (Hg) and methylmercury (MMHg) concentrations and fluxes in a flooded mudflat as well as the effects on water-level fluctuations on the air-surface exchange of mercury. A fast increase in dissolved Hg and MMHg concentrations was observed in overlying water in the first 10min of inundation and corresponded to a decrease in pore waters, suggesting a rapid export of Hg and MMHg from sediments to the water column. Estimations of daily advective transport exceeded the predicted diffusive fluxes by 5 orders of magnitude. A fast increase in dissolved gaseous mercury (DGM) concentration was also observed in the first 20-30min of inundation (maximum of 40pg L -1 ). Suspended particulate matter (SPM) concentrations were inversely correlated with DGM concentrations. Dissolved Hg variation suggested that biotic DGM production in pore waters is a significant factor in addition to the photochemical reduction of Hg. Mercury volatilization (ranged from 1.1 to 3.3ngm -2 h -1 ; average of 2.1ngm -2 h -1 ) and DGM production exhibited the same pattern with no significant time-lag suggesting a fast release of the produced DGM. These results indicate that Hg sediment/water exchanges in the physical dominated estuaries can be underestimated when the tidal effect is not considered. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Atmospheric mercury in Sweden, Northern Finland and Northern Europe. Results from national monitoring and European research

    Energy Technology Data Exchange (ETDEWEB)

    Waengberg, Ingvar; Munthe, John

    2001-01-01

    Atmospheric mercury concentrations and mercury fluxes measured during the period 1995 to 1999 at the AMAP master station of Pallas, a remote station in Northern Finland, and at Roervik an EMEP station located on the west coast of Sweden are reported. The results are discussed and compared with atmospheric mercury data generated within the EU-project, Mercury over Europe (MOE). Total particulate mercury exhibit a strong south to north gradient with the highest concentrations in the south, near source areas in Central Europe. Mercury in precipitation also exhibits a south to north gradient.

  9. Mercury Pollution Studies of Some Rivers Draining the Bibiani-Anwiaso-Bekwai Mining Community of South Western Ghana

    OpenAIRE

    V.K. Nartey; L.K. Doamekpor; S. Sarpong-Kumankuma; T. Akabzaa; F.K. Nyame; J.K. Kutor; D. Adotey

    2011-01-01

    The project assessed the extent of mercury pollution of some rivers that drain the Bibiani-Anwiaso- Bekwai district which is a typical mining community in the south western part of Ghana. In the study, surfacewater and sediment samples were collected from seven streams that drain this mining community and analyzed for total mercury, organic mercury and elemental mercury. Mercury concentrations of non-filtered water was determined using the ICP-OES after reduction with stannous chloride (SnCl2...

  10. Mercury risk in poultry in the Wanshan Mercury Mine, China

    International Nuclear Information System (INIS)

    Yin, Runsheng; Zhang, Wei; Sun, Guangyi; Feng, Zhaohui; Hurley, James P.; Yang, Liyuan; Shang, Lihai; Feng, Xinbin

    2017-01-01

    In this study, total mercury (THg) and methylmercury (MeHg) concentrations in muscles (leg and breast), organs (intestine, heart, stomach, liver) and blood were investigated for backyard chickens, ducks and geese of the Wanshan Mercury Mine, China. THg in poultry meat products range from 7.9 to 3917.1 ng/g, most of which exceeded the Chinese national standard limit for THg in meat (50 ng/g). Elevated MeHg concentrations (0.4–62.8 ng/g) were also observed in meat products, suggesting that poultry meat can be an important human MeHg exposure source. Ducks and geese showed higher Hg levels than chickens. For all poultry species, the highest Hg concentrations were observed in liver (THg: 23.2–3917.1 ng/g; MeHg: 7.1–62.8 ng/g) and blood (THg: 12.3–338.0 ng/g; MeHg: 1.4–17.6 ng/g). We estimated the Hg burdens in chickens (THg: 15.3–238.1 μg; MeHg: 2.2–15.6 μg), ducks (THg: 15.3–238.1 μg; MeHg: 3.5–14.7 μg) and geese (THg: 83.8–93.4 μg; MeHg: 15.4–29.7 μg). To not exceed the daily intake limit for THg (34.2 μg/day) and MeHg (6 μg/day), we suggested that the maximum amount (g) for chicken leg, breast, heart, stomach, intestine, liver, and blood should be 1384, 1498, 2315, 1214, 1081, 257, and 717, respectively; the maximum amount (g) for duck leg, breast, heart, stomach, intestine, liver, and blood should be 750, 1041, 986, 858, 752, 134, and 573, respectively; and the maximum amount (g) for goose leg, breast, heart, stomach, intestine, liver, and blood should be 941, 1051, 1040, 1131, 964, 137, and 562, respectively. - Highlights: • Elevated mercury levels were observed in poultry from Wanshan Mercury Mine, China. • Ducks and geese showed higher mercury levels than chickens. • Liver and blood showed the highest mercury levels. • Poultry can be an important dietary Hg exposure source for local residents. - High levels of Hg associated with poultry surrounding the Wanshan Mercury Mine pose a great risk of Hg exposure to

  11. Below a Historic Mercury Mine: Non-linear Patterns of Mercury Bioaccumulation in Aquatic Organisms

    Science.gov (United States)

    Haas, J.; Ichikawa, G.; Ode, P.; Salsbery, D.; Abel, J.

    2001-12-01

    Unlike most heavy metals, mercury is capable of bioaccumulating in aquatic food-chains, primarily because it is methylated by bacteria in sediment to the more toxic methylmercury form. Mercury concentrations in a number of riparian systems in California are highly elevated as a result of historic mining activities. These activities included both the mining of cinnabar in the coastal ranges to recover elemental mercury and the use of elemental mercury in the gold fields of the Sierra Nevada Mountains. The most productive mercury mining area was the New Almaden District, now a county park, located in the Guadalupe River drainage of Santa Clara County, where cinnabar was mined and retorted for over 100 years. As a consequence, riparian systems in several subwatersheds of the Guadalupe River drainage are contaminated with total mercury concentrations that exceed state hazardous waste criteria. Mercury concentrations in fish tissue frequently exceed human health guidelines. However, the potential ecological effects of these elevated mercury concentrations have not been thoroughly evaluated. One difficulty is in extrapolating sediment concentrations to fish tissue concentrations without accounting for physical and biological processes that determine bioaccumulation patterns. Many processes, such as methylation and demethylation of mercury by bacteria, assimilation efficiency in invertebrates, and metabolic rates in fish, are nonlinear, a factor that often confounds attempts to evaluate the effects of mercury contamination on aquatic food webs. Sediment, benthic macroinvertebrate, and fish tissue samples were collected in 1998 from the Guadalupe River drainage in Santa Clara County at 13 sites upstream and downstream from the historic mining district. Sediment and macroinvertebrate samples were analyzed for total mercury and methylmercury. Fish samples were analyzed for total mercury as whole bodies, composited by species and size. While linear correlations of sediment

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

    Science.gov (United States)

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

    2016-01-01

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

  13. Influences on Mercury Bioaccumulation Factors for the Savannah River

    International Nuclear Information System (INIS)

    Paller, M.H.

    2003-01-01

    Mercury TMDLs (Total Maximum Daily Loads) are a regulatory instrument designed to reduce the amount of mercury entering a water body and ultimately to control the bioaccumulation of mercury in fish. TMDLs are based on a BAF (bioaccumulation factor), which is the ratio of methyl mercury in fish to dissolved methyl mercury in water. Analysis of fish tissue and aqueous methyl mercury samples collected at a number of locations and over several seasons in a 118 km reach of the Savannah River demonstrated that species specific BAFs varied by factors of three to eight. Factors contributing to BAF variability were location, habitat and season related differences in fish muscle tissue mercury levels and seasonal differences in dissolved methyl mercury levels. Overall (all locations, habitats, and seasons) average BAFs were 3.7 x 106 for largemouth bass, 1.4 x 106 for sunfishes, and 2.5 x 106 for white catfish. Inaccurate and imprecise BAFs can result in unnecessary economic impact or insufficient protection of human health. Determination of representative and precise BAFs for mercury in fish FR-om large rivers necessitates collecting large and approximately equal numbers of fish and aqueous methyl mercury samples over a seasonal cycle FR-om the entire area and all habitats to be represented by the TMDL

  14. Biomarkers of mercury exposure at a mercury recycling facility in Ukraine

    Science.gov (United States)

    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.

  15. Oral and dental affections in mercury-exposed workers

    Energy Technology Data Exchange (ETDEWEB)

    Fahmy, M.S.

    1978-07-01

    A total of 222 mercury-exposed workers in the Chlor-Alkali plant in Kuwait were investigated for oral and dental affections. The levels of mercury-vapor ranged from 566.6 microgram/m3 to 0.3 microgram/m3 in different parts of the factory. The periods of exposure varied from 1 to 11 years. Although the level of mercury vapor in the air and the period of exposure proved to be the main factors as regards the oral signs and symptoms, the oral hygiene condition and the individual sensitivity played substantial roles. Oral affections were found not to be due to allergy to mercury.

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

    International Nuclear Information System (INIS)

    Burger, Joanna; Gochfeld, Michael

    2004-01-01

    There are abundant data and advisories for mercury levels in wild fish, but far fewer for commercial fish that compose a large majority of the fish most people eat. Until recently, relatively little attention has been devoted to examining mercury in canned tuna, despite its great importance in human diets. There is substantial media coverage of the benefits and risk from fish consumption, but few peer-reviewed data on canned tuna, the most commonly consumed fish in the United States. In this paper, we examine the levels of total mercury in canned tuna obtained from a New Jersey grocery store from 1998 to 2003, looking for temporal consistency within this data set and particularly for comparison with the Food and Drug Administration's 1991 study. We analyzed 168 cans individually for total mercury. All values are reported as parts per million (=μg/g) on a wet weight basis. In a subset of samples analyzed for total and inorganic mercury, the inorganic mercury was below detection levels; hence at least 89% of the mercury can be considered methylmercury. We found that white-style tuna had significantly more total mercury (mean 0.407 ppm) than light-style tuna (mean 0.118 ppm), presumably reflecting that 'white' tuna is albacore, a species relatively larger than the skipjack tuna, which is commonly available as 'light' or 'chunk light'. The maximum mercury in a can was 0.997 ppm, but 25% of white tuna samples exceeded 0.5 ppm. Data suggest a slight increase in levels since 1991, and mercury levels were significantly higher in 2001 than in other years. The mean level of mercury in white tuna (mean 0.407 ppm) was significantly higher than the mean value of 0.17 ppm currently used by the U.S. Food and Drug Administration (FDA) in its risk assessment and public information. There were no significant differences in mercury levels in tuna packed in oil compared to water. Draining contents had no effect on mercury levels, and the fluid, both oil and water, contained little

  17. Binding, distribution, and plant uptake of mercury in a soil from Oak Ridge, Tennessee, USA.

    Science.gov (United States)

    Han, Fengxiang X; Su, Yi; Monts, David L; Waggoner, Charles A; Plodinec, M John

    2006-09-15

    A large amount of mercury has been discharged on the U.S. Department of Energy's Oak Ridge Site (Tennessee) as a part of the U.S. nuclear weapon program during the 1950s through the early 1960s. Increases in mercury concentration in fish and in lower East Fork Poplar Creek of Oak Ridge have been recently reported. This is an experimental study mimicking the initial stage of transformation and redistribution of mercury in soils, which are comparable to those of the Oak Ridge site. The objectives of this study were to investigate potential transformation, distribution, and plant uptake of mercury compounds in soils. Results show that the H(2)O(2)-oxidizable mercury fraction (organically bound mercury) was the major solid-phase fraction in soils freshly contaminated with soluble mercury compounds, while cinnabar fraction was the major solid phase fraction in soils contaminated with HgS. Langmuir relationships were found between mercury concentrations in plant shoots and in soil solid-phase components. Mercury in HgS-contaminated soils was to some extent phytoavailable to plants. Mercury transformation occurred from more labile fractions into more stable fractions, resulting in strong binding of mercury and decreasing its phytoavailability in soils. In addition, high mercury losses from soils contaminated with soluble mercury compounds were observed during a growing season through volatilization, accounting for 20-62% of the total initial mercury in soils.

  18. Process for low mercury coal

    Science.gov (United States)

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

    1995-01-01

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

  19. Mercury (Environmental Health Student Portal)

    Science.gov (United States)

    ... in contact with) to mercury is by eating fish or shellfish that have high levels of mercury. You can also get sick from: Touching it Breathing it in Drinking contaminated water How can mercury ...

  20. Mercury speciation comparison. BrooksApplied Laboratories and Eurofins Frontier Global Sciences

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wilmarth, W. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-12-16

    The Savannah River National Laboratory (SRNL) was tasked with preparing and shipping samples for Hg speciation by Eurofins Frontier Global Sciences (FGS), Inc. in Bothell, WA on behalf of the Savannah River Remediation (SRR) Mercury Program Team. These samples were analyzed for seven species including: total mercury, dissolved mercury, inorganic mercury ((Hg(I) and Hg(II)), elemental mercury, methylmercury, ethylmercury, and dimethylmercury, with an eighth species, particulate mercury, calculated from the difference between total and dissolved mercury after subtracting the elemental mercury. The species fraction of total mercury measured has ranged broadly from a low of 32% to a high of 146%, though the vast majority of samples have been <100%. This can be expected since one is summing multiple values that each have at least a ± 20% measurement uncertainty. Two liquid waste tanks particularly important to understanding the distribution of mercury species in the Savannah River Site (SRS) Tank Farm were selected for a round robin analysis by Eurofins FGS and BrooksApplied Laboratories (BAL). The analyses conducted by BAL on the Tank 22 and 38 samples and their agreement with those obtained from Eurofins FGS for total mercury, dissolved mercury, methylmercury, ethylmercury, and dimethylmercury provide a strong degree of confidence in these species measurements

  1. 8 Assessment of the Level of Mercury Present in Soaps by the Use ...

    African Journals Online (AJOL)

    `123456789jkl''''#

    Abstract. Sixteen brands of soap were analysed for their total mercury content using cold vapour atomic fluorescence spectrometry. The aim was to find out if the soaps contained mercury and if so, what quantity. In addition, are the quantities acceptable for health purposes. Mercury was found to be present in some soaps ...

  2. Assessment of the Level of Mercury Present in Soaps by the Use of ...

    African Journals Online (AJOL)

    Sixteen brands of soap were analysed for their total mercury content using cold vapour atomic fluorescence spectrometry. The aim was to find out if the soaps contained mercury and if so, what quantity. In addition, are the quantities acceptable for health purposes. Mercury was found to be present in some soaps which did ...

  3. Mercury speciation comparison. BrooksApplied Laboratories and Eurofins Frontier Global Sciences

    International Nuclear Information System (INIS)

    Bannochie, C. J.; Wilmarth, W. R.

    2016-01-01

    The Savannah River National Laboratory (SRNL) was tasked with preparing and shipping samples for Hg speciation by Eurofins Frontier Global Sciences (FGS), Inc. in Bothell, WA on behalf of the Savannah River Remediation (SRR) Mercury Program Team. These samples were analyzed for seven species including: total mercury, dissolved mercury, inorganic mercury ((Hg(I) and Hg(II)), elemental mercury, methylmercury, ethylmercury, and dimethylmercury, with an eighth species, particulate mercury, calculated from the difference between total and dissolved mercury after subtracting the elemental mercury. The species fraction of total mercury measured has ranged broadly from a low of 32% to a high of 146%, though the vast majority of samples have been <100%. This can be expected since one is summing multiple values that each have at least a ± 20% measurement uncertainty. Two liquid waste tanks particularly important to understanding the distribution of mercury species in the Savannah River Site (SRS) Tank Farm were selected for a round robin analysis by Eurofins FGS and BrooksApplied Laboratories (BAL). The analyses conducted by BAL on the Tank 22 and 38 samples and their agreement with those obtained from Eurofins FGS for total mercury, dissolved mercury, methylmercury, ethylmercury, and dimethylmercury provide a strong degree of confidence in these species measurements

  4. Mercury exposure in young children living in New York City.

    Science.gov (United States)

    Rogers, Helen S; Jeffery, Nancy; Kieszak, Stephanie; Fritz, Pat; Spliethoff, Henry; Palmer, Christopher D; Parsons, Patrick J; Kass, Daniel E; Caldwell, Kathy; Eadon, George; Rubin, Carol

    2008-01-01

    Residential exposure to vapor from current or previous cultural use of mercury could harm children living in rental (apartment) homes. That concern prompted the following agencies to conduct a study to assess pediatric mercury exposure in New York City communities by measuring urine mercury levels: New York City Department of Health and Mental Hygiene's (NYCDOHMH) Bureau of Environmental Surveillance and Policy, New York State Department of Health/Center for Environmental Health (NYSDOHCEH), Wadsworth Center's Biomonitoring Program/Trace Elements Laboratory (WC-TEL), and Centers for Disease Control and Prevention (CDC). A previous study indicated that people could obtain mercury for ritualistic use from botanicas located in Brooklyn, Manhattan, and the Bronx. Working closely with local community partners, we concentrated our recruiting efforts through health clinics located in potentially affected neighborhoods. We developed posters to advertise the study, conducted active outreach through local partners, and, as compensation for participation in the study, we offered a food gift certificate redeemable at a local grocer. We collected 460 urine specimens and analyzed them for total mercury. Overall, geometric mean urine total mercury was 0.31 microg mercury/l urine. One sample was 24 microg mercury/l urine, which exceeded the (20 microg mercury/l urine) NYSDOH Heavy Metal Registry reporting threshold for urine mercury exposure. Geometric mean urine mercury levels were uniformly low and did not differ by neighborhood or with any clinical significance by children's ethnicity. Few parents reported the presence of mercury at home, in a charm, or other item (e.g., skin-lightening creams and soaps), and we found no association between these potential sources of exposure and a child's urinary mercury levels. All pediatric mercury levels measured in this study were well below a level considered to be of medical concern. This study found neither self-reported nor measured

  5. Mercury is Moon's brother

    International Nuclear Information System (INIS)

    Ksanfomalifi, L.V.

    1976-01-01

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

  6. Avaliação da perda de mercúrio total em peixe antes e após os processos de fritura e cocção Determination of mercury losses in fish after cooking

    Directory of Open Access Journals (Sweden)

    Aricelso Maia LIMAVERDE FILHO

    1999-01-01

    Full Text Available A perda de mercúrio contido em músculo de peixes (Piraíba, Brachyplatystoma ssp; Traíra, Hoplias malabaricus submetidos a dois distintos processos de cozimento foi investigada. Os resultados mostraram perdas variando entre 0 e 30% (base seca, indicando que a maior parte do mercúrio foi retida. Assim, tais processos não protegem as populações, que deles se utilizam, contra a exposição por ingestão ao mercúrio originariamente contido na amostra "in natura".Mercury losses from flesh fish after two cooking process were investigated. Results showed losses ranging from 0 to 30% (dry weight basis. Such result indicates that fish consuming populations are not protected from mercury exposition by the studied cooking processes.

  7. Assessment of atmospheric mercury emissions in Finland

    Science.gov (United States)

    Mukherjee; Melanen; Ekqvist; Verta

    2000-10-02

    This paper is part of the study of atmospheric emissions of heavy metals conducted by the Finnish Environment Institute in collaboration with the Technical Research Centre of Finland (VTT) under the umbrella of the Finnish Ministry of the Environment. The scope of our study is limited solely to anthropogenic mercury that is emitted directly to the atmosphere. This article addresses emission factors and trends of atmospheric mercury emissions during the 1990s and is based mainly on the database of the Finnish Environmental Administration. In addition, data based on the measurements taken by the VTT regarding emission factors have been used to estimate emissions of mercury from the incineration of waste. The study indicates that the total emission of mercury has decreased from 1140 kg in 1990 to 620 kg in 1997, while industrial and energy production have been on the increase simultaneously. The 45% emission reduction is due to improved gas cleaning equipment, process changes, automation, the installation of flue gas desulfurization process in coal-fired power plants and strict pollution control laws. In the past, some authors have estimated a higher mercury emission in Finland. In this study, it is also observed that there are no big changes in the quality of raw materials. Estimated emission factors can be of great help to management for estimating mercury emissions and also its risk assessment.

  8. Evaluation of mercury speciation and removal through air pollution control devices of a 190 MW boiler.

    Science.gov (United States)

    Wu, Chengli; Cao, Yan; Dong, Zhongbing; Cheng, Chinmin; Li, Hanxu; Pan, Weiping

    2010-01-01

    Air pollution control devices (APCDs) are installed at coal-fired power plants for air pollutant regulation. Selective catalytic reduction (SCR) and wet flue gas desulfurization (FGD) systems have the co-benefits of air pollutant and mercury removal. Configuration and operational conditions of APCDs and mercury speciation affect mercury removal efficiently at coal-fired utilities. The Ontario Hydro Method (OHM) recommended by the U.S. Environmental Protection Agency (EPA) was used to determine mercury speciation simultaneously at five sampling locations through SCR-ESP-FGD at a 190 MW unit. Chlorine in coal had been suggested as a factor affecting the mercury speciation in flue gas; and low-chlorine coal was purported to produce less oxidized mercury (Hg2+) and more elemental mercury (Hg0) at the SCR inlet compared to higher chlorine coal. SCR could oxidize elemental mercury into oxidized mercury when SCR was in service, and oxidation efficiency reached 71.0%. Therefore, oxidized mercury removal efficiency was enhanced through a wet FGD system. In the non-ozone season, about 89.5%-96.8% of oxidized mercury was controlled, but only 54.9%-68.8% of the total mercury was captured through wet FGD. Oxidized mercury removal efficiency was 95.9%-98.0%, and there was a big difference in the total mercury removal efficiencies from 78.0% to 90.2% in the ozone season. Mercury mass balance was evaluated to validate reliability of OHM testing data, and the ratio of mercury input in the coal to mercury output at the stack was from 0.84 to 1.08.

  9. Mercury concentrations in cattle from NW Spain.

    Science.gov (United States)

    López Alonso, M; Benedito, J L; Miranda, M; Castillo, C; Hernández, J; Shore, R F

    2003-01-20

    Mercury is a toxic metal that is released into the environment as a result of various industrial and agricultural processes. It can be accumulated by domestic animals and so contaminate human foodstuffs. To date, there is no information on mercury residues in livestock in Spain and the aim of the present study was to quantify the concentrations of mercury in cattle in two of the major regions in north-west Spain, Galicia (a largely rural region) and Asturias, which is characterised by heavy industry and mining. Total mercury concentrations were determined in tissue (liver, kidney and muscle) and blood from 284 calves (6-10 months old) and 56 cows (2-16 years old) from across the whole of the two regions. Mercury was usually detected in the kidney (62.4-87.5% of samples) but most (79.5-96%) liver, muscle and blood samples did not contain detectable residues. Renal mercury concentrations did not differ between male and female calves but were significantly greater in female calves than in cows. Unexpectedly, kidney mercury concentrations were significantly higher in calves from the predominantly rural region of Galicia (geometric mean: 12.2 microg/kg w.wt.) than in animals from the industrialised-mining region of Asturias (3.40 microg/kg w.wt.). Overall, mercury residues in cattle from NW Spain were similar to those reported in cattle from non-polluted areas in other countries and do not constitute a risk to animal or human health. Copyright 2002 Elsevier Science B.V.

  10. Mercury in terrestrial forested systems with highly elevated mercury deposition in southwestern China: The risk to insects and potential release from wildfires

    International Nuclear Information System (INIS)

    Zhou, Jun; Wang, Zhangwei; Sun, Ting; Zhang, Huan; Zhang, Xiaoshan

    2016-01-01

    Forests are considered a pool of mercury in the global mercury cycle. However, few studies have investigated the distribution of mercury in the forested systems in China. Tieshanping forest catchment in southwest China was impacted by mercury emissions from industrial activities and coal combustions. Our work studied mercury content in atmosphere, soil, vegetation and insect with a view to estimating the potential for mercury release during forest fires. Results of the present study showed that total gaseous mercury (TGM) was highly elevated and the annual mean concentration was 3.51 ± 1.39 ng m"−"2. Of the vegetation tissues, the mercury concentration follows the order of leaf/needle > root > bark > branch > bole wood for each species. Total ecosystem mercury pool was 103.5 mg m"−"2 and about 99.4% of the mercury resides in soil layers (0–40 cm). The remaining 0.6% (0.50 mg m"−"2) of mercury was stored in biomass. The large mercury stocks in the forest ecosystem pose a serious threat for large pluses to the atmospheric mercury during potential wildfires and additional ecological stress to forest insect: dung beetles, cicada and longicorn, with mercury concentration of 1983 ± 446, 49 ± 38 and 7 ± 5 ng g"−"1, respectively. Hence, the results obtained in the present study has implications for global estimates of mercury storage in forests, risks to forest insect and potential release to the atmosphere during wildfires. - Highlights: • Mercury in air, soil, biomass and insect were studied at a subtropical forest. • 99.4% of the total ecosystem mercury pools was resided in soil layers. • High mercury pools were large pulses to the atmosphere during potential wildfires. • High mercury deposition in forest pose an ecological stress to insect. - Large mercury pools in forest pose a serious threat for large pluses to the atmospheric mercury during potential wildfires and ecological stress to insect.

  11. Atmospheric mercury distribution in Northern Europe and in the Mediterranean region

    Science.gov (United States)

    Wängberg, I.; Munthe, J.; Pirrone, N.; Iverfeldt, Å.; Bahlman, E.; Costa, P.; Ebinghaus, R.; Feng, X.; Ferrara, R.; Gårdfeldt, K.; Kock, H.; Lanzillotta, E.; Mamane, Y.; Mas, F.; Melamed, E.; Osnat, Y.; Prestbo, E.; Sommar, J.; Schmolke, S.; Spain, G.; Sprovieri, F.; Tuncel, G.

    Mercury species in air have been measured at five sites in Northwest Europe and at five coastal sites in the Mediterranean region during measurements at four seasons. Observed concentrations of total gaseous mercury (TGM), total particulate mercury (TPM) and reactive gaseous mercury (RGM) were generally slightly higher in the Mediterranean region than in Northwest Europe. Incoming clean Atlantic air seems to be enriched in TGM in comparison to air in Scandinavia. Trajectory analysis of events where high concentrations of TPM simultaneously were observed at sites in North Europe indicate source areas in Central Europe and provide evidence of transport of mercury on particles on a regional scale.

  12. Annual ambient atmospheric mercury speciation measurement from Longjing, a rural site in Taiwan.

    Science.gov (United States)

    Fang, Guor-Cheng; Lo, Chaur-Tsuen; Cho, Meng-Hsien; Zhuang, Yuan-Jie; Tsai, Kai-Hsiang; Huang, Chao-Yang; Xiao, You-Fu

    2017-08-01

    The main purpose of this study was to monitor ambient air particulates and mercury species [RGM, Hg(p), GEM and total mercury] concentrations and dry depositions over rural area at Longjing in central Taiwan during October 2014 to September 2015. In addition, passive air sampler and knife-edge surrogate surface samplers were used to collect the ambient air mercury species concentrations and dry depositions, respectively, in this study. Moreover, direct mercury analyzer was directly used to detect the mercury Hg(p) and RGM concentrations. The result indicated that: (1) The average highest RGM, Hg(p), GEM and total mercury concentrations, and dry depositions were observed in January, prevailing dust storm occurred in winter season was the possible major reason responsible for the above findings. (2) The highest average RGM, Hg(p), GEM and total mercury concentrations, dry depositions and velocities were occurred in winter. This is because that China is the largest atmospheric mercury (Hg) emitter in the world. Its Hg emissions and environmental impacts need to be evaluated. (3) The results indicated that the total mercury ratios of Kaohsiung to that of this study were 5.61. This is because that Kaohsiung has the largest industry density (~60 %) in Taiwan. (4) the USA showed average lower mercury species concentrations when compared to those of the other world countries. The average ratios of China/USA values were 89, 76 and 160 for total mercury, RGM and Hg(p), respectively, during the years of 2000-2012.

  13. Modeling Mercury in Proteins

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-01-01

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

  14. Elevated mercury concentrations in humans of Madre de Dios, Peru.

    Directory of Open Access Journals (Sweden)

    Katy Ashe

    Full Text Available 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.

  15. Elevated mercury concentrations in humans of Madre de Dios, Peru.

    Science.gov (United States)

    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.

  16. Five-year records of mercury wet deposition flux at GMOS sites in the Northern and Southern hemispheres

    CSIR Research Space (South Africa)

    Sprovieri, F

    2017-02-01

    Full Text Available samples were collected for approximately 5 years at 17 selected GMOS monitoring sites located in the Northern and Southern hemispheres in the framework of the Global Mercury Observation System (GMOS) project. Total mercury (THg) exhibited annual...

  17. Mercury accumulation in bats near hydroelectric reservoirs in Peninsular Malaysia.

    Science.gov (United States)

    Syaripuddin, Khairunnisa; Kumar, Anjali; Sing, Kong-Wah; Halim, Muhammad-Rasul Abdullah; Nursyereen, Muhammad-Nasir; Wilson, John-James

    2014-09-01

    In large man-made reservoirs such as those resulting from hydroelectric dam construction, bacteria transform the relatively harmless inorganic mercury naturally present in soil and the submerged plant matter into toxic methylmercury. Methylmercury then enters food webs and can accumulate in organisms at higher trophic levels. Bats feeding on insects emerging from aquatic systems can show accumulation of mercury consumed through their insect prey. In this study, we investigated whether the concentration of mercury in the fur of insectivorous bat species was significantly higher than that in the fur of frugivorous bat species, sampled near hydroelectric reservoirs in Peninsular Malaysia. Bats were sampled at Temenggor Lake and Kenyir Lake and fur samples from the most abundant genera of the two feeding guilds-insectivorous (Hipposideros and Rhinolophus) and frugivorous (Cynopterus and Megaerops) were collected for mercury analysis. We found significantly higher concentrations of total mercury in the fur of insectivorous bats. Mercury concentrations also differed significantly between insectivorous bats sampled at the two sites, with bats from Kenyir Lake, the younger reservoir, showing higher mercury concentrations, and between the insectivorous genera, with Hipposideros bats showing higher mercury concentrations. Ten bats (H. cf. larvatus) sampled at Kenyir Lake had mercury concentrations approaching or exceeding 10 mg/kg, which is the threshold at which detrimental effects occur in humans, bats and mice.

  18. Monitoring of mercury concentration in atmosphere in Usti nad Labem

    International Nuclear Information System (INIS)

    Synek, V.; Baloch, T.; Otcenasek, J.; Kremlova, S.; Subrt, P.

    2007-01-01

    This study elaborates the observation of mercury pollution of the atmosphere in the city of Usti nad Labem. The biggest source of the polluting mercury in Usti nad Labem is the chlor-alkali production in the factory of Spolchemie Inc. The method of mercury determination applied is based on capturing the mercury contented in a volume of the air on an amalgamator and measuring the mercury by an atomic absorption spectrometer (Perkin -Elmer 4100ZL) equipped with a special adapter after a thermal release of the mercury from the amalgamator. The basic characteristics of this method were evaluated; e.g. the limit of detection and limit of determination are, respectively, 0.43 and 1.4 ng/m 3 , the relative expanded uncertainty is 28 %. The work gives results of long-term (1998-2006) observations in a few localities in Usti nad Labem situated in various distances from the mercury source (e.g. means of 28.6 and 14.1 ng/m3 were obtained, respectively, in places 350 and 700 m far from the electrolysis plant) and also in a different city (Duchcov). The cases with a higher mercury concentration are very frequent so the sets of the obtained results have lognormal distributions. This study statistically compares the total level and variability of the mercury concentrations in the time series. It also investigates their trends, correlations between them and meteorological influences upon the levels of mercury concentration in the air. The effect of the mercury emission from the chlor-alkali plant is dominant. It as the only factor determines when the cases with a high mercury concentration in the atmosphere occur. (author)

  19. Uptake of mercury vapor by wheat. An assimilation model

    International Nuclear Information System (INIS)

    Browne, C.L.; Fang, S.C.

    1978-01-01

    Using a whole-plant chamber and 203 Hg-labeled mercury, a quantitative study was made of the effect of environmental parameters on the uptake, by wheat (Triticum aestivum), of metallic mercury vapor, an atmospheric pollutant. Factors were examined in relation to their influence on components of the gas-assimilation model, U(Hg) = (C/sub A' -- C/sub L')/(r/sub L.Hg/ + r/sub M.Hg/) where U(Hg) is the rate of mercury uptake per unit leaf surface, C/sub A'/ is the ambient mercury vapor concentration, C/sub L'/ is the mercury concentration at immobilization sites within the plant (assumed to be zero), r/sub L.Hg/ is the total leaf resistance to mercury vapor exchange, and r/sub M.Hg/ is a residual term to account for unexplained physical and biochemical resistances to mercury vapor uptake. Essentially all mercury vapor uptake was confined to the leaves. r/sub L.Hg/ was particularly influenced by illumination (0 to 12.8 klux), but unaffected by ambient temperature (17 to 33 0 C) and mercury vapor concentration (0 to 40 μg m -3 ). The principal limitation to mercury vapor uptake was r/sub M.Hg/, which was linearly related to leaf temperature, but unaffected by mercury vapor concentration and illumination, except for apparent high values in darkness. Knowing C/sub A'/ and estimating r/sub L.Hg/ and r/sub M.Hg/ from experimental data, mercury vapor uptake by wheat in light was accurately predicted for several durations of exposure using the above model

  20. Intentional intravenous mercury injection

    African Journals Online (AJOL)

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

  1. Mercury's shifting, rolling past

    OpenAIRE

    Trulove, Susan

    2008-01-01

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

  2. Global Mercury Assessment 2013

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

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

  3. MESSENGER: Exploring Mercury's Magnetosphere

    Science.gov (United States)

    Slavin, James A.

    2008-01-01

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

  4. Validation of an analytical method for the determination of total mercury in urine samples using cold vapor atomic absorption spectrometry (CV-AAS); Validacao de metodologia analitica para determinacao de mercurio total em amostras de urina para espectrometria de absorcao atomica com geracao de vapor frio (CV-AAS)

    Energy Technology Data Exchange (ETDEWEB)

    Guilhen, Sabine Neusatz

    2009-07-01

    Mercury (Hg) is a toxic metal applied to a variety of products and processes, representing a risk to the health of occupationally or accidentally exposed subjects. Dental amalgam is a restorative material composed of metallic mercury, which use has been widely debated in the last decades. Due to the dubiety of the studies concerning dental amalgam, many efforts concerning this issue have been conducted. The Tropical Medicine Foundation (Tocantins, Brazil) has recently initiated a study to evaluate the environmental and occupational levels of exposure to mercury in dentistry attendants at public consulting rooms in the city of Araguaina (TO). In collaboration with this study, the laboratory of analysis at IPEN's Chemistry and Environment Center is undertaking the analysis of mercury levels in exposed subjects' urine samples using cold vapor atomic absorption spectrometry. This analysis requires the definition of a methodology capable of generating reliable results. Such methodology can only be implemented after a rigorous validation procedure. As part of this work, a series of tests were conducted in order to confirm the suitability of the selected methodology and to assert that the laboratory addresses all requirements needed for a successful implementation of the methodology. The following parameters were considered in order to test the method's performance: detection and quantitation limits, selectivity, sensitivity, linearity, accuracy and precision. The assays were carried out with certified reference material, which assures the traceability of the results. Taking into account the estimated parameters, the method can be considered suitable for the afore mentioned purpose. The mercury concentration found for the reference material was of (95,12 +- 11,70)mug.L{sup -1} with a recovery rate of 97%. The method was also applied to 39 urine samples, six of which (15%) showing urinary mercury levels above the normal limit of 10{mu}g.L{sup -1}. The obtained results fall

  5. Mercury enrichment and its effects on atmospheric emissions in cement plants of China

    Science.gov (United States)

    Wang, Fengyang; Wang, Shuxiao; Zhang, Lei; Yang, Hai; Wu, Qingru; Hao, Jiming

    2014-08-01

    The cement industry is one of the most significant anthropogenic sources of atmospheric mercury emissions worldwide. In this study of three typical Chinese cement plants, mercury in kiln flue gas was sampled using the Ontario Hydro Method (OHM), and solid samples were analyzed. Particulate matter recycling, preheating of raw materials, and the use of coal and flue gas desulfurization derived gypsum contributed to emissions of Hg in the air and to accumulation in cement. Over 90% of the mercury input was emitted into the atmosphere. Mercury emission factors were 0.044-0.072 g/t clinker for the test plants. The major species emitted into the atmosphere from cement plants is oxidized mercury, accounting for 61%-91% of the total mercury in flue gas. The results of this study help improve the accuracy of the mercury emission inventory in China and provide useful information for developing mercury controls.

  6. Mercury in Nordic ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Munthe, John; Waengberg, Ingvar (IVL Swedish Environmental Research Inst., Stockholm (SE)); Rognerud, Sigurd; Fjeld, Eirik (Norwegian Inst. for Water Research (NIVA), Oslo (Norway)); Verta, Matti; Porvari, Petri (Finnish Environment Inst. (SYKE), Helsinki (Finland)); Meili, Markus (Inst. of Applied Environmental Research (ITM), Stockholm (Sweden))

    2007-12-15

    This report provides a first comprehensive compilation and assessment of available data on mercury in air, precipitation, sediments and fish in the Nordic countries. The main conclusion is that mercury levels in Nordic ecosystems continue to be affected by long-range atmospheric transport. The geographical patterns of mercury concentrations in both sediments and fish are also strongly affected by ecosystem characteristics and in some regions possibly by historical pollution. An evaluation of geographical variations in mercury concentrations in precipitation indicates that the influence from anthropogenic sources from Central European areas is still significant. The annual variability of deposition is large and dependant of precipitation amounts. An evaluation of data from stations around the North Sea has indicated a significant decrease in mercury concentrations in precipitation indicating a continuous decrease of emissions in Europe (Waengberg et al., 2007). For mercury in air (TGM), the geographical pattern is less pronounced indicating the influence of mercury emissions and distribution over a larger geographical area (i.e. hemispherical transport). Comparison of recent (surficial) and historical lake sediments show significantly elevated concentrations of mercury most likely caused by anthropogenic atmospheric deposition over the past century. The highest pollution impact was observed in the coastal areas of southern Norway, in south western Finland and in Sweden from the coastal areas in the southwest across the central parts to the north-east. The general increase in recent versus old sediments was 2-5 fold. Data on mercury in Nordic freshwater fish was assembled and evaluated with respect to geographical variations. The fish data were further compared with temporal and spatial trends in mercury deposition and mercury contamination of lake sediments in order to investigate the coupling between atmospheric transport and deposition of mercury and local mercury

  7. Return to Mercury: a global perspective on MESSENGER's first Mercury flyby.

    Science.gov (United States)

    Solomon, Sean C; McNutt, Ralph L; Watters, Thomas R; Lawrence, David J; Feldman, William C; Head, James W; Krimigis, Stamatios M; Murchie, Scott L; Phillips, Roger J; Slavin, James A; Zuber, Maria T

    2008-07-04

    In January 2008, the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft became the first probe to fly past the planet Mercury in 33 years. The encounter revealed that Mercury is a dynamic system; its liquid iron-rich outer core is coupled through a dominantly dipolar magnetic field to the surface, exosphere, and magnetosphere, all of which interact with the solar wind. MESSENGER images confirm that lobate scarps are the dominant tectonic landform and record global contraction associated with cooling of the planet. The history of contraction can be related to the history of volcanism and cratering, and the total contractional strain is at least one-third greater than inferred from Mariner 10 images. On the basis of measurements of thermal neutrons made during the flyby, the average abundance of iron in Mercury's surface material is less than 6% by weight.

  8. Experimental dosing of wetlands with coagulants removes mercury from surface water and decreases mercury bioaccumulation in fish

    Science.gov (United States)

    Ackerman, Joshua T.; Kraus, Tamara E.C.; Fleck, Jacob A.; Krabbenhoft, David P.; Horwarth, William R.; Bachand, Sandra M.; Herzog, Mark; Hartman, Christopher; Bachand, Philip A.M.

    2015-01-01

    Mercury pollution is widespread globally, and strategies for managing mercury contamination in aquatic environments are necessary. We tested whether coagulation with metal-based salts could remove mercury from wetland surface waters and decrease mercury bioaccumulation in fish. In a complete randomized block design, we constructed nine experimental wetlands in California’s Sacramento–San Joaquin Delta, stocked them with mosquitofish (Gambusia affinis), and then continuously applied agricultural drainage water that was either untreated (control), or treated with polyaluminum chloride or ferric sulfate coagulants. Total mercury and methylmercury concentrations in surface waters were decreased by 62% and 63% in polyaluminum chloride treated wetlands and 50% and 76% in ferric sulfate treated wetlands compared to control wetlands. Specifically, following coagulation, mercury was transferred from the filtered fraction of water into the particulate fraction of water which then settled within the wetland. Mosquitofish mercury concentrations were decreased by 35% in ferric sulfate treated wetlands compared to control wetlands. There was no reduction in mosquitofish mercury concentrations within the polyaluminum chloride treated wetlands, which may have been caused by production of bioavailable methylmercury within those wetlands. Coagulation may be an effective management strategy for reducing mercury contamination within wetlands, but further studies should explore potential effects on wetland ecosystems.

  9. Experimental dosing of wetlands with coagulants removes mercury from surface water and decreases mercury bioaccumulation in fish.

    Science.gov (United States)

    Ackerman, Joshua T; Kraus, Tamara E C; Fleck, Jacob A; Krabbenhoft, David P; Horwath, William R; Bachand, Sandra M; Herzog, Mark P; Hartman, C Alex; Bachand, Philip A M

    2015-05-19

    Mercury pollution is widespread globally, and strategies for managing mercury contamination in aquatic environments are necessary. We tested whether coagulation with metal-based salts could remove mercury from wetland surface waters and decrease mercury bioaccumulation in fish. In a complete randomized block design, we constructed nine experimental wetlands in California's Sacramento-San Joaquin Delta, stocked them with mosquitofish (Gambusia affinis), and then continuously applied agricultural drainage water that was either untreated (control), or treated with polyaluminum chloride or ferric sulfate coagulants. Total mercury and methylmercury concentrations in surface waters were decreased by 62% and 63% in polyaluminum chloride treated wetlands and 50% and 76% in ferric sulfate treated wetlands compared to control wetlands. Specifically, following coagulation, mercury was transferred from the filtered fraction of water into the particulate fraction of water which then settled within the wetland. Mosquitofish mercury concentrations were decreased by 35% in ferric sulfate treated wetlands compared to control wetlands. There was no reduction in mosquitofish mercury concentrations within the polyaluminum chloride treated wetlands, which may have been caused by production of bioavailable methylmercury within those wetlands. Coagulation may be an effective management strategy for reducing mercury contamination within wetlands, but further studies should explore potential effects on wetland ecosystems.

  10. Atmospheric wet deposition of mercury in North America

    Energy Technology Data Exchange (ETDEWEB)

    Sweet, C.W.; Prestbo, E.; Brunette, B.

    1999-07-01

    Currently, 39 states in the US and 5 Canadian provinces have issued advisories about the dangers of eating mercury-contaminated fish taken from waters within their boundaries. The problem is most severe in the Great Lakes region, the Northeast US states, the Canadian maritime provinces, and in south Florida where many lakes and streams contain fish with concentrations of 1 ppm or higher. For many rural and remote locations, atmospheric deposition is the primary source of mercury. In 1995, the National Atmospheric Deposition Program (NADP) initiated a program to monitor total mercury and methylmercury (MMHg) in wet deposition (rain and snow) in North America. In this program, the Mercury Deposition Network (MDN), individual monitoring sites are funded and operated by a variety of local, state, and federal agencies. However, sampling and analysis are coordinated through a central laboratory so that all of the samples are collected and analyzed using the same protocols. Weekly wet-only precipitation samples are collected using an all-glass sampling train and special handling techniques. Analysis is by cold vapor atomic fluorescence spectrometry using USEPA Method 1631 for total mercury. Nearly 40 MDN sites are in operation in 1999. Most of the sites are in the eastern US and Canada. During 1996 and 1997, the volume-weighted mean concentration of total mercury in precipitation collected at 22 sites ranged from 6.0 to 18.9 ng/L. Annual deposition varied between 2.1 and 25.3 {micro} g/m{sup 2}. The average weekly wet deposition of total mercury is more than three times higher in the summer (June-August) than in the winter (December-February). This increase is due to both higher amounts of precipitation and higher concentrations of mercury in precipitation during the summer. The highest values for mercury concentration in precipitation and wet deposition of mercury were measured in the southeastern US.

  11. Getting Mercury out of Schools.

    Science.gov (United States)

    1999

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

  12. Application of neutron activation analysis to the determination of total mercury and other elements of interest in soil and sediment samples from Serra do Navio and Vila Nova River Basin, Amapa, Brazil; Aplicacao do metodo de ativacao neutronica a determinacao do mercurio total e outros elementos de interesse em amostras de solo e sedimento da Serra do Navio e Bacia do Rio Vila Nova, Amapa

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Cristina

    1997-07-01

    In this work it is presented a survey on total mercury determination by a radiochemical method in sediment and soil samples from two regions, in the state of Amapa: Serra do Navio (background area) and Vila Nova river basin (gold mining area). The method consisted in leaching of the irradiated samples with acqua regia in a Parr bomb, and heating in microwave oven, for one minute. Then the solvent extraction technique was applied, using bismuth diethyldithiocarbamate (Bi(DDC){sub 3}) as extractant agent. The organic phase, containing {sup 197}Hg and {sup 203}Hg radioisotopes, was measured in a gamma spectrometer with hyper pure Ge detector. This method eliminated the interference of the 279.54 keV photopeak of {sup 75}Se on 279.2 keV photopeak of {sup 203}Hg, besides improving counting statistics of both Hg radioisotopes. The elements As, Ba, Br, Ce, Co, Cr, Cs, Eu, Fe, Hf, Ho, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, Ti, U, V, W, Yb, Zn and Zr were also determined by the instrumental neutron activation analysis. Two irradiation series were carried out to quantify these elements in soil and sediment samples; a short term irradiation allowed to evaluate Mg, Mn, Na, Ti and V levels, and by long term irradiation, the other elements were determined. Precision and accuracy of radiochemical procedure were verified by means of analysis of the reference materials Buffalo River Sediment and Lake Sediment, for sediments and GXR-5, for soils. For the instrumental analysis, the reference materials Buffalo River Sediment, Soil 7, JB-1 and Oyster Tissue were used. The samples were also submitted to X ray diffraction, in Instituto de Geoscience-USP, to observe mercury behaviour with mineralogy. Aluminium concentration was determined by X ray fluorescence method, in the Department of Materials, IPEN/CNEN-SP, making possible enrichment factor calculation so that mercurial contamination in the gold mining area (Vila Nova river basin) could be evaluated. The mercury

  13. Analysis of Halogen-Mercury Reactions in Flue Gas

    Energy Technology Data Exchange (ETDEWEB)

    Paula Buitrago; Geoffrey Silcox; Constance Senior; Brydger Van Otten

    2010-01-01

    Oxidized mercury species may be formed in combustion systems through gas-phase reactions between elemental mercury and halogens, such as chorine or bromine. This study examines how bromine species affect mercury oxidation in the gas phase and examines the effects of mixtures of bromine and chlorine on extents of oxidation. Experiments were conducted in a bench-scale, laminar flow, methane-fired (300 W), quartz-lined reactor in which gas composition (HCl, HBr, NO{sub x}, SO{sub 2}) and temperature profile were varied. In the experiments, the post-combustion gases were quenched from flame temperatures to about 350 C, and then speciated mercury was measured using a wet conditioning system and continuous emissions monitor (CEM). Supporting kinetic calculations were performed and compared with measured levels of oxidation. A significant portion of this report is devoted to sample conditioning as part of the mercury analysis system. In combustion systems with significant amounts of Br{sub 2} in the flue gas, the impinger solutions used to speciate mercury may be biased and care must be taken in interpreting mercury oxidation results. The stannous chloride solution used in the CEM conditioning system to convert all mercury to total mercury did not provide complete conversion of oxidized mercury to elemental, when bromine was added to the combustion system, resulting in a low bias for the total mercury measurement. The use of a hydroxylamine hydrochloride and sodium hydroxide solution instead of stannous chloride showed a significant improvement in the measurement of total mercury. Bromine was shown to be much more effective in the post-flame, homogeneous oxidation of mercury than chlorine, on an equivalent molar basis. Addition of NO to the flame (up to 400 ppmv) had no impact on mercury oxidation by chlorine or bromine. Addition of SO{sub 2} had no effect on mercury oxidation by chlorine at SO{sub 2} concentrations below about 400 ppmv; some increase in mercury oxidation

  14. Development of novel activated carbon-based adsorbents for the control of mercury emissions from coal-fired power plants

    Energy Technology Data Exchange (ETDEWEB)

    Radisav D. Vidic

    1999-03-01

    In addition to naturally occurring mercury sources, anthropogenic activities increase the mercury loading to the environment. Although not all produced mercury is dissipated directly into the environment, only minor portions of the total production are stocked or recycled, and the rest of the mercury and its compounds is finally released in some way into atmosphere, surface waters and soil, or ends in landfills dumps, and refuse. Since mercury and its compounds are highly toxic, their presence in the environment constitutes potential impact on all living organisms, including man. The first serious consequence of industrial mercury discharges causing neurological disorder even death occurred in Minimata, Japan in 1953. Systematic studies showed that mercury poisoning is mainly found in fish-eating populations. However, various levels of mercury are also found in food other than fish. During the past several decades, research has been conducted on the evaluation of risks due to exposure to mercury and the development of control technologies for mercury emissions. In 1990, the Clean Air Act Amendments listed mercury, along with 10 other metallic species, as a hazardous air pollutant (HAP). This has further stimulated research for mercury control during the past several years. The impact of mercury on humans, sources of mercury in the environment, current mercury control strategies and the objective of this research are discussed in this section.

  15. Anthropogenic mercury emissions from 1980 to 2012 in China.

    Science.gov (United States)

    Huang, Ying; Deng, Meihua; Li, Tingqiang; Japenga, Jan; Chen, Qianqian; Yang, Xiaoe; He, Zhenli

    2017-07-01

    China was considered the biggest contributor for airborne mercury in the world but the amount of mercury emission in effluents and solid wastes has not been documented. In this study, total national and regional mercury emission to the environment via exhaust gases, effluents and solid wastes were accounted with updated emission factors and the amount of goods produced and/or consumed. The national mercury emission in China increased from 448 to 2151 tons during the 1980-2012 period. Nearly all of the emissions were ended up as exhaust gases and solid wastes. The proportion of exhaust gases decreased with increasing share of solid wastes and effluents. Of all the anthropogenic sources, coal was the most important contributor in quantity, followed by mercury mining, gold smelting, nonferrous smelting, iron steel production, domestic wastes, and cement production, with accounting for more than 90% of the total emission. There was a big variation of regional cumulative mercury emission during 1980-2012 in China, with higher emissions occurred in eastern areas and lower values in the western and far northern regions. The biggest cumulative emission occurred in GZ (Guizhou), reaching 3974 t, while the smallest cumulative emission was lower than 10 t in XZ (Tibet). Correspondingly, mercury accumulation in soil were higher in regions with larger emissions in unit area. Therefore, it is urgent to reduce anthropogenic mercury emission and subsequent impact on ecological functions and human health. Copyright © 2017. Published by Elsevier Ltd.

  16. Accumulation of mercury in Typha domingensis under field conditions.

    Science.gov (United States)

    Lominchar, M A; Sierra, M J; Millán, R

    2015-01-01

    Typha species is a common wetland plant used in the treatment of urban and industrial effluents. But, despite their widespread implementation, there are not many studies based on the behaviour of this plant growing in an areas affected by mercury. The present work investigates the ability of Typha domingensis to accumulate mercury under field conditions. The study area was along the Valdeazogues river which flows through the Almadén mining district (Ciudad Real, Spain) that is considered the largest mercury reservoir in the world. The mercury concentration in different plant fractions was measured as well as the available and total concentration in the bottom sediments. The results showed that the highest mercury concentrations were found in the belowground organs. T. domingensis had a high efficiency to accumulate mercury in their organs although available metal concentrations in the environment did not exceed 0.16 mg kg(-1). Bioaccumulation factors (BAF) ranged between 121 and 3168 in roots. Furthermore, significant correlations were found between mercury concentration in all plant organs and Hg in sediments (both total and available). These results demonstrated that T. domingensis could be used as a biomonitor as well as in phytoextraction technology in areas affected by mercury. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Modeling dynamic exchange of gaseous elemental mercury at polar sunrise.

    Science.gov (United States)

    Dastoor, Ashu P; Davignon, Didier; Theys, Nicolas; Van Roozendael, Michel; Steffen, Alexandra; Ariya, Parisa A

    2008-07-15

    At polar sunrise, gaseous elemental mercury (GEM) undergoes an exceptional dynamic exchange in the air and at the snow surface during which GEM can be rapidly removed from the atmosphere (the so-called atmospheric mercury depletion events (AMDEs)) as well as re-emitted from the snow within a few hours to days in the Polar Regions. Although high concentrations of total mercury in snow following AMDEs is well documented, there is very little data available on the redox transformation processes of mercury in the snow and the fluxes of mercury at the air/snow interface. Therefore, the net gain of mercury in the Polar Regions as a result of AMDEs is still an open question. We developed a new version of the global mercury model, GRAHM, which includes for the first time bidirectional surface exchange of GEM in Polar Regions in spring and summer by developing schemes for mercury halogen oxidation, deposition, and re-emission. Also for the first time, GOME satellite data-derived boundary layer concentrations of BrO have been used in a global mercury model for representation of halogen mercury chemistry. Comparison of model simulated and measured atmospheric concentrations of GEM at Alert, Canada, for 3 years (2002-2004) shows the model's capability in simulating the rapid cycling of mercury during and after AMDEs. Brooks et al. (1) measured mercury deposition, reemission, and net surface gain fluxes of mercury at Barrow, AK, during an intensive measurement campaign for a 2 week period in spring (March 25 to April 7, 2003). They reported 1.7, 1.0 +/- 0.2, and 0.7 +/- 0.2 microg m(-2) deposition, re-emission, and net surface gain, respectively. Using the optimal configuration of the model, we estimated 1.8 microg m(-2) deposition, 1.0 microg m(-2) re-emission, and 0.8 microg m(-2) net surface gain of mercury for the same time period at Barrow. The estimated net annual accumulation of mercury within the Arctic Circle north of 66.5 degrees is approximately 174 t with +/-7 t of

  18. Mercury emission and speciation of coal-fired power plants in China

    Science.gov (United States)

    Wang, S. X.; Zhang, L.; Li, G. H.; Wu, Y.; Hao, J. M.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.

    2010-02-01

    Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of Selective Catalytic Reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.

  19. Mercury emission and speciation of coal-fired power plants in China

    Directory of Open Access Journals (Sweden)

    S. X. Wang

    2010-02-01

    Full Text Available Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of Selective Catalytic Reduction (SCR, electrostatic precipitators (ESP, and flue gas desulfurization (FGD using the Ontario Hydro Method (OHM. The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92–27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66–94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.

  20. Mercury's Dynamic Magnetic Tail

    Science.gov (United States)

    Slavin, James A.

    2010-01-01

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

  1. 40 CFR Table 3 to Subpart Ddddd of... - Operating Limits for Boilers and Process Heaters With Mercury Emission Limits and Boilers and...

    Science.gov (United States)

    2010-07-01

    ... operating limits: If you demonstrate compliance with applicable mercury and/or total selected metals... applicable emission limits for mercury and/or total selected metals. 2. Fabric filter control a. Install and... applicable emission limits for mercury and/or total selected metals. 4. Dry scrubber or carbon injection...

  2. Biomarkers of mercury exposure at a mercury recycling facility in Ukraine.

    Science.gov (United States)

    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 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.

  3. MESSENGER at Mercury: Early Orbital Operations

    Science.gov (United States)

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

    2013-01-01

    angles. Targeted areas have been selected for spectral coverage into the ultraviolet with the Ultraviolet and Visible Spectrometer (UVVS). MESSENGER's Mercury Laser Altimeter is acquiring topographic profiles when the slant range to Mercury's surface is less than 1800 km, encompassing latitudes from 20 deg. S to the north pole. Topography over the remainder of the southern hemisphere will be derived from stereo imaging, radio occultations, and limb profiles. MESSENGER's radio science experiment is determining Mercury's gravity field from Doppler signals acquired during frequent downlinks. MESSENGER's Magnetometer is measuring the vector magnetic field both within Mercury's magnetosphere and in Mercury's solar wind environment at an instrument sampling rate of up to 20 samples/s. The UVVS is determining the three-dimensional, time-dependent distribution of Mercury's exospheric neutral and ionic species via their emission lines. During each spacecraft orbit, the Energetic Particle Spectrometer measures energetic electrons and ions, and the Fast Imaging Plasma Spectrometer measures the energies and mass per charge of thermal plasma components, both within Mercury's magnetosphere and in Mercury's solar-wind environment. The primary mission observation sequence will continue for one Earth year, until March 2012. An extended mission, currently under discussion with NASA, would add a second year of orbital observations targeting a set of focused follow-on questions that build on observations to date and take advantage of the more active Sun expected during 2012-2013. MESSENGER's total primary mission cost, projected at $446 M in real-year dollars, is comparable to that of Mariner 10 after adjustment for inflation.

  4. Recovery of mercury from mercury compounds via electrolytic methods

    Science.gov (United States)

    Grossman, Mark W.; George, William A.

    1988-01-01

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

  5. FINAL REPORT ON THE AQUATIC MERCURY ASSESSMENT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Halverson, N

    2008-09-30

    In February 2000, the United States Environmental Protection Agency (EPA) Region 4 issued a proposed Total Maximum Daily Load (TMDL) for total mercury in the middle and lower Savannah River. The initial TMDL, which would have imposed a 1 ng/l mercury limit for discharges to the middle/lower Savannah River, was revised to 2.8 ng/l in the final TMDL released in February 2001. The TMDL was intended to protect people from the consumption of contaminated fish, which is the major route of mercury exposure to humans. The most bioaccumulative form of mercury is methylmercury, which is produced in aquatic environments by the action of microorganisms on inorganic mercury. Because of the environmental and economic significance of the mercury discharge limits that would have been imposed by the TMDL, the Savannah River Site (SRS) initiated several studies concerning: (1) mercury in SRS discharges, SRS streams and the Savannah River, (2) mercury bioaccumulation factors for Savannah River fish, (3) the use of clams to monitor the influence of mercury from tributary streams on biota in the Savannah River, and (4) mercury in rainwater falling on the SRS. The results of these studies are presented in detail in this report. The first study documented the occurrence, distribution and variation of total and methylmercury at SRS industrial outfalls, principal SRS streams and the Savannah River where it forms the border with the SRS. All of the analyses were performed using the EPA Method 1630/31 ultra low-level and contaminant-free techniques for measuring total and methylmercury. Total mercury at National Pollutant Discharge Elimination System (NPDES) outfalls ranged from 0.31-604 ng/l with a mean of 8.71 ng/l. Mercury-contaminated groundwater was the source for outfalls with significantly elevated mercury concentrations. Total mercury in SRS streams ranged from 0.95-15.7 ng/l. Mean total mercury levels in the streams varied from 2.39 ng/l in Pen Branch to 5.26 ng/l in Tims Branch

  6. Sexual differences in the distribution and retention of organic and inorganic mercury in methyl mercury-treated rats

    International Nuclear Information System (INIS)

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

    1986-01-01

    At 56 days of age, male and female Long-Evans rats received 1 μmole of 203 Hg-labeled mercuric chloride per kilogram sc and total, organic, and inorganic mercury contents and concentrations in tissues were determined for up to 98 days postdosing. When expressed on a concentration basis, the only significant sexual difference was in the higher average concentration of organic mercury in the kidneys of females. When expressed on a tissue content basis, significant male-female differences in the kinetics (sex x time interactions) of organic mercury retention were found in kidney, brain, skeletal muscle, pelt, and whole body. Significant sex x time interactions in the concentrations of organic mercury were found in kidney, skeletal muscle, and whole body. Kinetics of retention and concentration of inorganic Hg in the pelt differed significantly for males and females. Discordance of degree of statistical significance of differences in mercury contents and concentrations reflected in part differences in relative body composition of males and females. Differences in integrated exposure were estimated by the female-to-male ratio of areas under retention curves. Reconstruction of whole body organic and inorganic mercury burdens from constituent tissues indicated that integrated exposures of males and females to inorganic mercury were equal but females had a lower integrated exposure to organic mercury. Integrated exposure of liver to either form of mercury was about equal in males and females. However, the integrated exposure of the brain of females to inorganic mercury was 2.19 times that of males suggest'ing a sexual difference in accumulation or retention of inorganic mercury in the nervous system

  7. Metallic mercury recycling. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Beck, M.A.

    1994-07-01

    Metallic mercury is known to be a hazardous material and is regulated as such. The disposal of mercury, usually by landfill, is expensive and does not remove mercury from the environment. Results from the Metallic Mercury Recycling Project have demonstrated that metallic mercury is a good candidate for reclamation and recycling. Most of the potential contamination of mercury resides in the scum floating on the surface of the mercury. Pinhole filtration was demonstrated to be an inexpensive and easy way of removing residues from mercury. The analysis method is shown to be sufficient for present release practices, and should be sufficient for future release requirements. Data from tests are presented. The consistently higher level of activity of the filter residue versus the bulk mercury is discussed. Recommendations for the recycling procedure are made.

  8. Metallic mercury recycling. Final report

    International Nuclear Information System (INIS)

    Beck, M.A.

    1994-01-01

    Metallic mercury is known to be a hazardous material and is regulated as such. The disposal of mercury, usually by landfill, is expensive and does not remove mercury from the environment. Results from the Metallic Mercury Recycling Project have demonstrated that metallic mercury is a good candidate for reclamation and recycling. Most of the potential contamination of mercury resides in the scum floating on the surface of the mercury. Pinhole filtration was demonstrated to be an inexpensive and easy way of removing residues from mercury. The analysis method is shown to be sufficient for present release practices, and should be sufficient for future release requirements. Data from tests are presented. The consistently higher level of activity of the filter residue versus the bulk mercury is discussed. Recommendations for the recycling procedure are made

  9. Validation of an analytical method for the determination of total mercury in urine samples using cold vapor atomic absorption spectrometry (CV-AAS); Validacao de metodologia analitica para determinacao de mercurio total em amostras de urina por espectrometria de absorcao atomica com geracao de vapor frio (CV-AAS)

    Energy Technology Data Exchange (ETDEWEB)

    Guilhen, Sabine Neusatz

    2009-07-01

    Mercury (Hg) is a toxic metal applied to a variety of products and processes, representing a risk to the health of occupationally or accidentally exposed subjects. Dental amalgam is a restorative material composed of metallic mercury, which use has been widely debated in the last decades. Due to the dubiety of the studies concerning dental amalgam, many efforts concerning this issue have been conducted. The Tropical Medicine Foundation (Tocantins, Brazil) has recently initiated a study to evaluate the environmental and occupational levels of exposure to mercury in dentistry attendants at public consulting rooms in the city of Araguaina (TO). In collaboration with this study, the laboratory of analysis at IPEN's Chemistry and Environment Center is undertaking the analysis of mercury levels in exposed subjects' urine samples using cold vapor atomic absorption spectrometry. This analysis requires the definition of a methodology capable of generating reliable results. Such methodology can only be implemented after a rigorous validation procedure. As part of this work, a series of tests were conducted in order to confirm the suitability of the selected methodology and to assert that the laboratory addresses all requirements needed for a successful implementation of the methodology. The following parameters were considered in order to test the method’s performance: detection and quantitation limits, selectivity, sensitivity, linearity, accuracy and precision. The assays were carried out with certified reference material, which assures the traceability of the results. Taking into account the estimated parameters, the method can be considered suitable for the afore mentioned purpose. The mercury concentration found for the reference material was of (95,12 ± 11,70)μg.L{sup -1} with a recovery rate of 97%. The method was also applied to 39 urine samples, six of which (15%) showing urinary mercury levels above the normal limit of 10μg.L{sup −1}. The obtained

  10. Validation of an analytical method for the determination of total mercury in urine samples using cold vapor atomic absorption spectrometry (CV-AAS); Validacao de metodologia analitica para determinacao de mercurio total em amostras de urina para espectrometria de absorcao atomica com geracao de vapor frio (CV-AAS)

    Energy Technology Data Exchange (ETDEWEB)

    Guilhen, Sabine Neusatz

    2009-07-01

    Mercury (Hg) is a toxic metal applied to a variety of products and processes, representing a risk to the health of occupationally or accidentally exposed subjects. Dental amalgam is a restorative material composed of metallic mercury, which use has been widely debated in the last decades. Due to the dubiety of the studies concerning dental amalgam, many efforts concerning this issue have been conducted. The Tropical Medicine Foundation (Tocantins, Brazil) has recently initiated a study to evaluate the environmental and occupational levels of exposure to mercury in dentistry attendants at public consulting rooms in the city of Araguaina (TO). In collaboration with this study, the laboratory of analysis at IPEN's Chemistry and Environment Center is undertaking the analysis of mercury levels in exposed subjects' urine samples using cold vapor atomic absorption spectrometry. This analysis requires the definition of a methodology capable of generating reliable results. Such methodology can only be implemented after a rigorous validation procedure. As part of this work, a series of tests were conducted in order to confirm the suitability of the selected methodology and to assert that the laboratory addresses all requirements needed for a successful implementation of the methodology. The following parameters were considered in order to test the method's performance: detection and quantitation limits, selectivity, sensitivity, linearity, accuracy and precision. The assays were carried out with certified reference material, which assures the traceability of the results. Taking into account the estimated parameters, the method can be considered suitable for the afore mentioned purpose. The mercury concentration found for the reference material was of (95,12 +- 11,70)mug.L{sup -1} with a recovery rate of 97%. The method was also applied to 39 urine samples, six of which (15%) showing urinary mercury levels above the normal limit of 10{mu}g.L{sup -1}. The

  11. Mercury removal in utility wet scrubber using a chelating agent

    Science.gov (United States)

    Amrhein, Gerald T.

    2001-01-01

    A method for capturing and reducing the mercury content of an industrial flue gas such as that produced in the combustion of a fossil fuel or solid waste adds a chelating agent, such as ethylenediaminetetraacetic acid (EDTA) or other similar compounds like HEDTA, DTPA and/or NTA, to the flue gas being scrubbed in a wet scrubber used in the industrial process. The chelating agent prevents the reduction of oxidized mercury to elemental mercury, thereby increasing the mercury removal efficiency of the wet scrubber. Exemplary tests on inlet and outlet mercury concentration in an industrial flue gas were performed without and with EDTA addition. Without EDTA, mercury removal totaled 42%. With EDTA, mercury removal increased to 71%. The invention may be readily adapted to known wet scrubber systems and it specifically provides for the removal of unwanted mercury both by supplying S.sup.2- ions to convert Hg.sup.2+ ions into mercuric sulfide (HgS) and by supplying a chelating agent to sequester other ions, including but not limited to Fe.sup.2+ ions, which could otherwise induce the unwanted reduction of Hg.sup.2+ to the form, Hg.sup.0.

  12. Carbon bed mercury emissions control for mixed waste treatment.

    Science.gov (United States)

    Soelberg, Nick; Enneking, Joe

    2010-11-01

    Mercury has various uses in nuclear fuel reprocessing and other nuclear processes, and so it is often present in radioactive and mixed (radioactive and hazardous) wastes. Compliance with air emission regulations such as the Hazardous Waste Combustor (HWC) Maximum Achievable Control Technology (MACT) standards can require off-gas mercury removal efficiencies up to 99.999% for thermally treating some mixed waste streams. Test programs have demonstrated this level of off-gas mercury control using fixed beds of granular sulfur-impregnated activated carbon. Other results of these tests include (1) the depth of the mercury control mass transfer zone was less than 15-30 cm for the operating conditions of these tests; (2) MERSORB carbon can sorb mercury up to 19 wt % of the carbon mass; and (3) the spent carbon retained almost all (98.3-99.99%) of the mercury during Toxicity Characteristic Leachability Procedure (TCLP) tests, but when even a small fraction of the total mercury dissolves, the spent carbon can fail the TCLP test when the spent carbon contains high mercury concentrations.

  13. Permafrost stores a globally significant amount of mercury

    Science.gov (United States)

    Schaefer, K. M.; Schuster, P. F.; Antweiler, R.; Aiken, G.; DeWild, J.; Gryziec, J. D.; Gusmeroli, A.; Hugelius, G.; Jafarov, E.; Krabbenhoft, D. P.; Liu, L.; Herman-Mercer, N. M.; Mu, C.; Roth, D. A.; Schaefer, T.; Striegl, R. G.; Wickland, K.; Zhang, T.

    2017-12-01

    Changing climate in northern regions is causing permafrost to thaw with major implications for the cycling of mercury in arctic and subarctic ecosystems. Permafrost occurs in nearly one quarter of the Earth's Northern Hemisphere. We measured total soil mercury concentration in 588 samples from 13 soil permafrost cores from the interior and the North Slope of Alaska. The median concentration was 47.7±23.4 ng Hg g soil-1 and the median ratio of Hg to carbon was 1.56±0.86 µg Hg g C-1. We estimate Alaskan permafrost stores 56±32 kilotons of mercury and the entire northern hemisphere permafrost land mass stores 773±441 kilotons of mercury. This increases estimates of mercury stored in soils by 60%, making permafrost the second largest reservoir of mercury on the planet. Climate projections indicate extensive permafrost thawing, releasing mercury into the environment through a variety of mechanisms, for example, terrestrial transport via dissolved organic carbon (DOC), gaseous elemental mercury (GEM) evasion, forest fires, atmospheric mixing processes with ozone, and Springtime atmospheric Hg depletion after the polar sunrise. These findings have major implications for terrestrial and aquatic life, the world's fisheries, and ultimately human health.

  14. The effect of mercury on trees and their mycorrhizal fungi

    Energy Technology Data Exchange (ETDEWEB)

    Jean-Philippe, Sharon R., E-mail: jeanphil@utk.edu [University of Tennessee, Department of Forestry, Wildlife and Fisheries, 274 Ellington Plant Science Building, 2431 Joe Johnson Dr., Knoxville, TN 37996-4563 (United States); Franklin, Jennifer A., E-mail: jafranklin@utk.edu [University of Tennessee, Department of Forestry, Wildlife and Fisheries, 274 Ellington Plant Science Building, 2431 Joe Johnson Dr., Knoxville, TN 37996-4563 (United States); Buckley, David S., E-mail: dbuckley@utk.edu [University of Tennessee, Department of Forestry, Wildlife and Fisheries, 274 Ellington Plant Science Building, 2431 Joe Johnson Dr., Knoxville, TN 37996-4563 (United States); Hughes, Karen, E-mail: khughes@utk.edu [University of Tennessee, Ecology and Evolutionary Biology, 350 Hesler Biology Building and Greenhouse, 1406 Circle Drive, Knoxville, TN 37996-1610 (United States)

    2011-10-15

    The Oak Ridge Reservation, established in 1942, was the designated site for the construction of the atomic bomb. During a 20-year period from 1944 to 1963 radioactive and toxic chemical pollutants, especially mercury compounds were released into the surrounding waterways. Tree diversity and mycorrhizal presence and abundance were analyzed in the mercury-contaminated floodplains of East Fork Poplar Creek Oak Ridge (EFPC) (Tennessee). A subsequent greenhouse study was conducted to assess the phytotoxic effects of different mercuric solutions on Platanus occidentalis (American Sycamore), inoculated with soils from EFPC. Total soil mercury in the field had no effect on tree diversity. Organic species of mercury proved to be more toxic than inorganic species of mercury and soil inoculants from EFPC had no protective effects against Hg toxicity in our greenhouse study. Comparison of the effects of mercury contamination in our field and greenhouse studies was difficult due to uncontrolled factors. - Highlights: > Heavy metals effects on ecosystems may be difficult to pinpoint in the field. > Toxic effects of mercury depend on its chemical form and concentration. > Mycorrhizae have been shown to be increase heavy metal tolerance in host plant. - Though evidence suggests that mercury-contaminated soils may reduce tree and fungal populations, there are tolerant species that may remain and survive following contamination.

  15. Mercury Test on macroalgae from Burung and Tikus Island, Jakarta

    Science.gov (United States)

    Novianty, H.; Herandarudewi, S. M. C.; Suratno

    2018-04-01

    Environmental pollution, caused by the introduction of hazardous substances such as heavy metals into coastal waters, affects not only the condition of the waters but also the source of food that will be contaminated by hazardous metals, one of them is mercury (Hg). Mercury is toxic metal which could cause damage to the human body in certain threshold amounts. The aim of this study was to determin the content of mercury in several species of algae from Burung and Tikus Island, Jakarta. This study was using a descriptive method. The samples were collected from Burung and Tikus Island by simple rundown sampling. Mercury level was measured by NIC3000 mercury analyzer tool. The results showed that none of the mercury levels have passed 0.5 mg/kg (the safety standart level of mercury by SNI (Indonesian National Standard)7387 in 2019) mangrove. From tikus Island had lower total mercury than the ones from Burung Island. Burung Island is located near Pari Island which is a residential area, where pollution is more likely to occur.

  16. Mercury mass measurement in fluorescent lamps via neutron activation analysis

    International Nuclear Information System (INIS)

    Viererbl, L.; Vinš, M.; Lahodová, Z.; Fuksa, A.; Kučera, J.; Koleška, M.; Voljanskij, A.

    2015-01-01

    Mercury is an essential component of fluorescent lamps. Not all fluorescent lamps are recycled, resulting in contamination of the environment with toxic mercury, making measurement of the mercury mass used in fluorescent lamps important. Mercury mass measurement of lamps via instrumental neutron activation analysis (NAA) was tested under various conditions in the LVR-15 research reactor. Fluorescent lamps were irradiated in different positions in vertical irradiation channels and a horizontal channel in neutron fields with total fluence rates from 3×10 8 cm −2 s −1 to 10 14 cm −2 s −1 . The 202 Hg(n,γ) 203 Hg nuclear reaction was used for mercury mass evaluation. Activities of 203 Hg and others induced radionuclides were measured via gamma spectrometry with an HPGe detector at various times after irradiation. Standards containing an Hg 2 Cl 2 compound were used to determine mercury mass. Problems arise from the presence of elements with a large effective cross section in luminescent material (europium, antimony and gadolinium) and glass (boron). The paper describes optimization of the NAA procedure in the LVR-15 research reactor with particular attention to influence of neutron self-absorption in fluorescent lamps. - Highlights: • Mercury is an essential component of fluorescent lamps. • Fluorescent lamps were irradiated in neutron fields in research reactor. • 203 Hg induced radionuclide activity was measured using gamma spectrometry. • Mercury mass in fluorescent lamps can be measured by neutron activation analysis.

  17. The tectonics of Mercury

    International Nuclear Information System (INIS)

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

    1988-01-01

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

  18. Intentional intravenous mercury injection

    African Journals Online (AJOL)

    Elemental mercury is the well-known silver liquid and usually causes pulmonary, neurological and ... suicidal ideation or features of major depression. Clinically the patient was .... medically at this stage and consider surgical intervention later.

  19. Mercury's Dynamic Magnetosphere

    Science.gov (United States)

    Imber, S. M.

    2018-05-01

    The global dynamics of Mercury's magnetosphere will be discussed, focussing on observed asymmetries in the magnetotail and on the precipitation of particles of magnetospheric origin onto the nightside planetary surface.

  20. Mercury analysis in hair

    DEFF Research Database (Denmark)

    Esteban, Marta; Schindler, Birgit K; Jiménez-Guerrero, José A

    2015-01-01

    Human biomonitoring (HBM) is an effective tool for assessing actual exposure to chemicals that takes into account all routes of intake. Although hair analysis is considered to be an optimal biomarker for assessing mercury exposure, the lack of harmonization as regards sampling and analytical...... assurance program (QAP) for assessing mercury levels in hair samples from more than 1800 mother-child pairs recruited in 17 European countries. To ensure the comparability of the results, standard operating procedures (SOPs) for sampling and for mercury analysis were drafted and distributed to participating...... laboratories. Training sessions were organized for field workers and four external quality-assessment exercises (ICI/EQUAS), followed by the corresponding web conferences, were organized between March 2011 and February 2012. ICI/EQUAS used native hair samples at two mercury concentration ranges (0...

  1. Mercury's Early Geologic History

    Science.gov (United States)

    Denevi, B. W.; Ernst, C. M.; Klima, R. L.; Robinson, M. S.

    2018-05-01

    A combination of geologic mapping, compositional information, and geochemical models are providing a better understanding of Mercury's early geologic history, and allow us to place it in the context of the Moon and the terrestrial planets.

  2. Hair Mercury Concentrations and Fish Consumption Patterns in Florida Residents

    Directory of Open Access Journals (Sweden)

    Adam M. Schaefer

    2014-06-01

    Full Text Available Mercury exposure through the consumption of fish and shellfish represents a significant public health concern in the United States. Recent research has demonstrated higher seafood consumption and subsequent increased risk of methylmercury exposure among subpopulations living in coastal areas. The identification of high concentrations of total mercury in blood and skin among resident Atlantic bottlenose dolphins (Tursiops truncatus in the Indian River Lagoon (IRL, a coastal estuary in Florida, alerted us to a potential public health hazard in the contiguous human population. Therefore, we analyzed hair mercury concentrations of residents living along the IRL and ascertained their sources and patterns of seafood consumption. The total mean mercury concentration for 135 residents was 1.53 ± 1.89 µg/g. The concentration of hair mercury among males (2.02 ± 2.38 µg/g was significantly higher than that for females (0.96 ± 0.74 µg/g (p < 0.01. Log transformed hair mercury concentration was significantly associated with the frequency of total seafood consumption (p < 0.01. Individuals who reported consuming seafood once a day or more were 3.71 (95% CI 0.84–16.38 times more likely to have a total hair mercury concentration over 1.0 µg/g, which corresponds approximately to the U.S. EPA reference dose, compared to those who consumed seafood once a week or less. Hair mercury concentration was also significantly higher among individuals who obtained all or most of their seafood from local recreational sources (p < 0.01. The elevated human mercury concentrations mirror the elevated concentrations observed in resident dolphins in the same geographical region. The current study is one of the first to apply the concept of a sentinel animal to a contiguous human population.

  3. Mercury CEM Calibration

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-03-31

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

  4. Cutaneous mercury granuloma

    OpenAIRE

    Kalpana A Bothale; Sadhana D Mahore; Sushil Pande; Trupti Dongre

    2013-01-01

    Cutaneous mercury granuloma is rarely encountered. Clinically it may pose difficulty in diagnosis. Here, we report a 23-year-old male presented with erythematous, nodular lesions over the forearm and anterior aspect of chest wall. Metallic mercury in tissue sections appear as dark black, opaque, spherical globules of varying size and number. They are surrounded by granulomatous foreign-body reaction. It is composed of foreign body giant cells and mixed inflammatory infiltrate composed of hist...

  5. Mercury in human hair

    International Nuclear Information System (INIS)

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

    1980-10-01

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

  6. Determination of Mercury Daily Intake and Hair-to-Blood Mercury Concentration Ratio in People Resident of the Coast of the Persian Gulf, Iran.

    Science.gov (United States)

    Okati, Narjes; Esmaili-Sari, Abbas

    2018-01-01

    The objectives of this study were to understand the mercury daily intake and hair-to-blood mercury ratio in fishermen and non-fishermen families in the coast of the Persian Gulf in Iran. The mean mercury concentration in the hair of fishermen and non-fishermen families was 5.76 and 2.27 μg/g, respectively. The mean mercury concentrations of RBCs were obtained for fishermen families and non-fishermen families: 35.96 and 17.18 μg/L, respectively. Hair mercury concentrations in 17% of people were higher than 10 μg/g, the No Observed Adverse Effects Level set by the World Health Organization. 78% of people had a blood mercury value > 5.8 μg/L, the standard level set by the U.S. Environmental Protection Agency. A significant correlation (r = 0.94, p = 0.000) was seen between log hair and RBCs mercury concentrations. The mean mercury daily intake for fishermen and non-fishermen families was 0.42 and 0.20 µg/kg BW per day, respectively. The mean mercury daily intake of fishermen families was higher than the provisional tolerable daily intake (0.23 µg/kg BW per day) suggested by the Joint Expert Committee on Food Additives. Mercury daily intake significantly correlated with fish consumption (r = 0.50, p = 0.000) and log hair mercury (r = 0.88, p = 0.000). The total mean of hair-to-blood mercury concentration ratio was 306. We conclude that the use of mercury concentrations in the hair and RBCs could have been suitable biomarkers for predicting mercury exposure of people with a high rate of fish consumption.

  7. Mercury-cycling in surface waters and in the atmosphere - species analysis for the investigation of transformation and transport properties of mercury

    International Nuclear Information System (INIS)

    Ebinghaus, R.; Hintelmann, H.; Wilken, R.D.

    1994-01-01

    The river Elbe has been one of the most contaminated rivers with regard to mercury for many years. In 1991 a length-profile has been measured for mercury and methylmercury (CH 3 Hg + ) from Obristvi, Czech Republic, to the German bight. Total mercury has been measured by cold vapor atomic absorption spectrometry (CVAAS). The organo mercury compounds have been separated by high performance liquid chromatography (HPLC) connected on-line to an atomic fluorescence spectrometer (AFS) by a continuous flow-system. Total mercury up to 120 mg Hg + /kg and CH 3 Hg + concentrations up to 130 μg CH 3 Hg + /kg could be detected in special sites. The formation of CH 3 Hg + in sediments can be caused besides the methylation of mercury, by sulphate reducing or methanogenic bacteria and transmethylation reactions with organometals. Atmospheric mercury concentrations have been measured at three different European sites. Samples have been collected on gold-coated glass balls or on quartz wool, respectively. After thermal desorption mercury has been determined using the two step amalgamation technique with AFS detection. Compared to natural background concentrations of total gaseous mercury (TGM), slightly increased levels could be detected at a rural site in Germany. This increase can probably be explained by long-range transport processes. Within the vicinity of a inactivated mercury production plant high concentrations of up to 13.5 ng/m 3 particle associated mercury (Hg part ) have been detected. Consequently, dry deposition of mercury in the particulate form can intensify the total deposition flux close to Hg-emitting sources. (orig.)

  8. Mercury levels of marine fish commonly consumed in Peninsular Malaysia.

    Science.gov (United States)

    Ahmad, Nurul Izzah; Noh, Mohd Fairulnizal Mohd; Mahiyuddin, Wan Rozita Wan; Jaafar, Hamdan; Ishak, Ismail; Azmi, Wan Nurul Farah Wan; Veloo, Yuvaneswary; Hairi, Mohd Hairulhisam

    2015-03-01

    This study was conducted to determine the concentration of total mercury in the edible portion of 46 species of marine fish (n = 297) collected from selected major fish landing ports and wholesale markets throughout Peninsular Malaysia. Samples were collected in June to December 2009. Prior to analysis, the fish samples were processed which consisted of drying at 65 °C until a constant weight was attained; then, it was grounded and digested by a microwave digestion system. The analytical determination was carried out by using a mercury analysis system. Total mercury concentration among fish species was examined. The results showed that mercury concentrations were found significantly higher (p mercury concentrations were also higher in carnivorous fish especially in the species with more predatory feeding habits. Besides, the family group of Latidae (0.537 ± 0.267 mg/kg in dried weight), Dasyatidae (0.492 ± 0.740 mg/kg in dried weight), and Lutjanidae (0.465 ± 0.566 mg/kg in dried weight) showed significantly (p mercury levels compared to other groups. Fish collected from Port Klang (0.563 ± 0.509 mg/kg in dry weight), Kuala Besar (0.521 ± 0.415 mg/kg in dry weight), and Pandan (0.380 ± 0.481 mg/kg in dry weight) were significantly higher (p = 0.014) in mercury concentrations when compared to fish from other sampling locations. Total mercury levels were significantly higher (p 20 cm) and were positively related with fish size (length and weight) in all fish samples. Despite the results, the level of mercury in marine fish did not exceed the permitted levels of Malaysian and JECFA guideline values at 0.5 mg/kg methylmercury in fish.

  9. Does mercury contamination reduce body condition of endangered California clapper rails?

    International Nuclear Information System (INIS)

    Ackerman, Joshua T.; Overton, Cory T.; Casazza, Michael L.; Takekawa, John Y.; Eagles-Smith, Collin A.; Keister, Robin A.; Herzog, Mark P.

    2012-01-01

    We examined mercury exposure in 133 endangered California clapper rails (Rallus longirostris obsoletus) within tidal marsh habitats of San Francisco Bay, California from 2006 to 2010. Mean total mercury concentrations were 0.56 μg/g ww in blood (range: 0.15–1.43), 9.87 μg/g fw in head feathers (3.37–22.0), 9.04 μg/g fw in breast feathers (3.68–20.2), and 0.57 μg/g fww in abandoned eggs (0.15–2.70). We recaptured 21 clapper rails and most had low within-individual variation in mercury. Differences in mercury concentrations were largely attributed to tidal marsh site, with some evidence for year and quadratic date effects. Mercury concentrations in feathers were correlated with blood, and slopes differed between sexes (R 2 = 0.58–0.76). Body condition was negatively related to mercury concentrations. Model averaged estimates indicated a potential decrease in body mass of 20–22 g (5–7%) over the observed range of mercury concentrations. Our results indicate the potential for detrimental effects of mercury contamination on endangered California clapper rails in tidal marsh habitats. - Highlights: ► We examined mercury in endangered California clapper rails within tidal marshes. ► Differences in mercury concentrations were largely attributed to tidal marsh site. ► Mercury concentrations in blood, feathers, and eggs were considered elevated. ► Body condition was negatively related to mercury concentrations. ► Results indicate detrimental effects of mercury on endangered clapper rails. - Mercury contamination in endangered California clapper rails was influenced by tidal marsh site and increased mercury resulted in reduced bird body condition.

  10. Mercury Quick Facts: Health Effects of Mercury Exposure

    Science.gov (United States)

    ... 2012 What are the Health Effects of Mercury Exposure? The health effects that can be caused by breathing mercury depend ... they breathe faster and have smaller lungs. Health effects caused by long-term exposure to mercury vapors • • Anxiety • • Excessive shyness • • Anorexia • • Sleeping ...

  11. Mercury pOIsonIng

    African Journals Online (AJOL)

    A case of mercury poisoning is reported and clinical observations of 6 .... fish ingested and occupational exposure. .... exposed to mercury as a result of inadequate industrial safety standards, and ... WHO Tech Rep Ser 1980; No. 674: 102-115.

  12. Mercury Study Report to Congress

    Science.gov (United States)

    EPA's Report to Congress on Mercury provides an assessment of the magnitude of U.S. mercury emissions by source, the health and environmental implications of those emissions, and the availability and cost of control technologies.

  13. True Polar Wander of Mercury

    Science.gov (United States)

    Keane, J. T.; Matsuyama, I.

    2018-05-01

    We use new MESSENGER gravity data to investigate how impact basins and volcanic provinces alter Mercury's moments of inertia. We find that Mercury has reoriented tens of degrees over its history, affecting tectonics, volatiles, and more.

  14. Mercury Emissions: The Global Context

    Science.gov (United States)

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

  15. Fate modeling of mercury species and fluxes estimation in an urban river

    International Nuclear Information System (INIS)

    Tong, Yindong; Zhang, Wei; Chen, Cen; Chen, Long; Wang, Wentao; Hu, Xindi; Wang, Huanhuan; Hu, Dan; Ou, Langbo; Wang, Xuejun; Wang, Qiguang

    2014-01-01

    The fate and transfer of mercury in urban river is an important environmental concern. In this study, QWASI (Quantitative Water–Air–Sediment Interaction) model was selected to estimate the levels of total mercury and three mercury species in water and sediment, and was used to quantify the fluxes of mercury at water/air and sediment/water interfaces of an urban river. The predicted mercury levels in water and sediments were closed to the measured values. Water inflow, re-suspension of sediment and diffusion from sediment to water are major input sources of mercury in water. The net mercury transfer flux from water to air was 0.16 ng/(m 2 h). At the sediment/water interface, a net total mercury transfer of 1.32 ng/(m 2 h) from water to sediment was seen. In addition to the existing dynamic flux chambers measurement, this model method could provide a new perspective to identify the distribution and transfer of mercury in the urban river. -- Highlights: • QWASI could be a good tool to quantify transfer and fate of mercury in environment. • Distribution and flux of mercury species in an urban river was modeled. • Mercury in water mainly came from water inflow, sediment re-suspension and diffusion. • Net mercury transfer from water to air and sediment were 0.16 and 1.32 ng/(m 2 h). -- Quantitative Water–Air–Sediment Interaction model was used to quantify the transfer and fate of mercury in an urban river

  16. Mercury's magnetic field and interior

    International Nuclear Information System (INIS)

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

    1988-01-01

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

  17. Níveis de mercúrio em atum sólido enlatado comercializado na cidade do Rio de Janeiro Total mercury levels in canned tuna fish commercialized at the Rio de Janeiro city, Brazil

    Directory of Open Access Journals (Sweden)

    Allegra YALLOUZ

    2001-01-01

    Full Text Available No presente trabalho, estudou-se o nível de mercúrio em atum sólido enlatado, comercializado na cidade do Rio de Janeiro. Foram analisadas 39 amostras, pertencente a 5 marcas e lotes distintos, utilizando-se a espectrometria de absorção atômica pela técnica de vapor-frio. Os resultados obtidos demonstraram que 53% das amostras apresentaram um teor acima do máximo recomendado, sendo que somente uma entre as cinco marcas estudadas apresentou todas as amostras com níveis dentro dos limites tolerados. Tais resultados demonstram a necessidade de um maior controle da qualidade destes produtos.The present study investigated the mercury levels in canned tuna fish, commercialized in the Rio de Janeiro city, Brazil. Thirty nine samples from five different makers were analyzed by cold vapor atomic absorption spectrometry. The results showed that 53% of the samples presented levels above the WHO (World Health Organization recommended value, and only one from the five suppliers presented all their samples below this level. Such results indicate that it urges a better quality control for this food.

  18. Solid-phase partitioning of mercury in artisanal gold mine tailings from selected key areas in Mindanao, Philippines, and its implications for mercury detoxification.

    Science.gov (United States)

    Opiso, Einstine M; Aseneiro, John Paul J; Banda, Marybeth Hope T; Tabelin, Carlito B

    2018-03-01

    The solid-phase partitioning of mercury could provide necessary data in the identification of remediation techniques in contaminated artisanal gold mine tailings. This study was conducted to determine the total mercury content of mine wastes and identify its solid-phase partitioning through selective sequential extraction coupled with cold vapour atomic absorption spectroscopy. Samples from mine tailings and the carbon-in-pulp (CIP) process were obtained from selected key areas in Mindanao, Philippines. The results showed that mercury use is still prevalent among small-scale gold miners in the Philippines. Tailings after ball mill-gravity concentration (W-BM and Li-BM samples) from Mt Diwata and Libona contained high levels of mercury amounting to 25.024 and 6.5 mg kg -1 , respectively. The most prevalent form of mercury in the mine tailings was elemental/amalgamated mercury, followed by water soluble, exchangeable, organic and strongly bound phases, respectively. In contrast, mercury content of carbon-in-pulp residues were significantly lower at only 0.3 and 0.06 mg kg -1 for P-CIP (Del Pilar) and W-CIP (Mt Diwata), respectively. The bulk of mercury in P-CIP samples was partitioned in residual fraction while in W-CIP samples, water soluble mercury predominated. Overall, this study has several important implications with regards to mercury detoxification of contaminated mine tailings from Mindanao, Philippines.

  19. The Impact of Impoundment on Mercury Bioaccumulation in Fish Downstream from a Newly Constructed Reservoir, Wujiang River, Southwest China.

    Science.gov (United States)

    Li, Sixin; Zhou, Lianfeng; Chang, Jianbo; Yang, Zhi; Hu, Juxiang; Hongjun, Wang

    2017-11-01

    Mercury concentrations in fish were investigated downstream from a newly impounded subtropical reservoir in August 2008. After 6-7 months of reservoir impoundment, mean mercury concentration in fish from downstream is significantly increased by 1.9 times. Not only carnivorous fish but also benthic fish had significantly higher total mercury concentrations than others. No significant correlation was found between total mercury concentrations and body length or weight of 13 fish species. Compared with the pre-impoundment, total mercury in fish from downstream is significantly increased by reservoir impoundment, but the increased rate is lower than those in subarctic and temperate areas. Fish samples surpassed the Chinese hygienic standard for tolerances of mercury in foods increased by 4.3%. More attention should be given to fish mercury levels from downstream sites to prevent possible adverse effects on the health of local people.

  20. MERCURY IN MARINE LIFE DATABASE

    Science.gov (United States)

    The purpose of the Mercury in Marine Life Project is to organize information on estuarine and marine species so that EPA can better understand both the extent of monitoring for mercury and level of mercury contamination in the biota of coastal environments. This report follows a ...

  1. Reference Atmosphere for Mercury

    Science.gov (United States)

    Killen, Rosemary M.

    2002-01-01

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

  2. Were mercury emission factors for Chinese non-ferrous metal smelters overestimated? Evidence from onsite measurements in six smelters

    International Nuclear Information System (INIS)

    Zhang Lei; Wang Shuxiao; Wu Qingru; Meng Yang; Yang Hai; Wang Fengyang; Hao Jiming

    2012-01-01

    Non-ferrous metal smelting takes up a large proportion of the anthropogenic mercury emission inventory in China. Zinc, lead and copper smelting are three leading sources. Onsite measurements of mercury emissions were conducted for six smelters. The mercury emission factors were 0.09–2.98 g Hg/t metal produced. Acid plants with the double-conversion double-absorption process had mercury removal efficiency of over 99%. In the flue gas after acid plants, 45–88% was oxidized mercury which can be easily scavenged in the flue gas scrubber. 70–97% of the mercury was removed from the flue gas to the waste water and 1–17% to the sulfuric acid product. Totally 0.3–13.5% of the mercury in the metal concentrate was emitted to the atmosphere. Therefore, acid plants in non-ferrous metal smelters have significant co-benefit on mercury removal, and the mercury emission factors from Chinese non-ferrous metal smelters were probably overestimated in previous studies. - Highlights: ► Acid plants in smelters provide significant co-benefits for mercury removal (over 99%). ► Most of the mercury in metal concentrates for smelting ended up in waste water. ► Previously published emission factors for Chinese metal smelters were probably overestimated. - Acid plants in smelters have high mercury removal efficiency, and thus mercury emission factors for Chinese non-ferrous metal smelters were probably overestimated.

  3. Electrolytic recovery of mercury enriched in isotopic abundance

    Science.gov (United States)

    Grossman, Mark W.

    1991-01-01

    The present invention is directed to a method of electrolytically extracting liquid mercury from HgO or Hg.sub.2 Cl.sub.2. Additionally there are disclosed two related techniques associated with the present invention, namely (1) a technique for selectively removing product from different regions of a long photochemical reactor (photoreactor) and (2) a method of accurately measuring the total quantity of mercury formed as either HgO or Hg.sub.2 Cl.sub.2.

  4. Mercury Biogeochemical Cycling in the Ocean and Policy Implications

    OpenAIRE

    Mason, Robert P.; Choi, Anna L.; Fitzgerald, William F.; Hammerschmidt, Chad R.; Lamborg, Carl H.; Soerensen, Anne L.; Sunderland, Elsie M.

    2012-01-01

    Anthropogenic activities have enriched mercury in the biosphere by at least a factor of three, leading to increases in total mercury (Hg) in the surface ocean. However, the impacts on ocean fish and associated trends in human exposure as a result of such changes are less clear. Here we review our understanding of global mass budgets for both inorganic and methylated Hg species in ocean seawater. We consider external inputs from atmospheric deposition and rivers as well as internal production ...

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

    Science.gov (United States)

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

    2011-12-01

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

  6. Integrity Monitoring of Mercury Discharge Lamps

    Science.gov (United States)

    Tjoelker, Robert L.

    2010-01-01

    Mercury discharge lamps are critical in many trapped ion frequency standard applications. An integrity monitoring system can be implemented using end-of-life signatures observed in operational mercury discharge lamps, making it possible to forecast imminent failure and to take action to mitigate the consequences (such as switching to a redundant system). Mercury lamps are used as a source of 194-nm ultraviolet radiation for optical pumping and state selection of mercury trapped ion frequency standards. Lamps are typically fabricated using 202Hg distilled into high-purity quartz, or other 194-nm transmitting material (e.g., sapphire). A buffer gas is also placed into the bulb, typically a noble gas such as argon, neon, or krypton. The bulbs are driven by strong RF fields oscillating at .200 MHz. The lamp output may age over time by two internal mechanisms: (1) the darkening of the bulb that attenuates light transmission and (2) the loss of mercury due to migration or chemical interactions with the bulb surface. During fabrication, excess mercury is placed into a bulb, so that the loss rate is compensated with new mercury emanating from a cool tip or adjacent reservoir. The light output is nearly constant or varies slightly at a constant rate for many months/years until the mercury source is depleted. At this point, the vapor pressure abruptly falls and the total light output and atomic clock SNR (signal-to-noise ratio) decrease. After several days to weeks, the light levels decrease to a point where the atomic clock SNR is no longer sufficient to stay in lock, or the lamp self-extinguishes. This signature has been observed in four separate end-of-life lamp failures while operating in the Deep Space Network (DSN). A simple integrator circuit can observe and document steady-state lamp behavior. When the light levels drop over a predetermined time interval by a specified amount (e.g., 20 percent), an alarm is set. For critical operational applications, such as the DSN

  7. Spatial and temporal variations of mercury levels in Okefenokee invertebrates: Southeast Georgia

    International Nuclear Information System (INIS)

    George, Bagie M.; Batzer, Darold

    2008-01-01

    Accumulation of mercury in wetland ecosystems has raised concerns about impacts on wetland food webs. This study measured concentrations of mercury in invertebrates of the Okefenokee Swamp in Georgia, focusing on levels in amphipods, odonates, and crayfish. We collected and analyzed total mercury levels in these invertebrates from 32 sampling stations across commonly occurring sub-habitats. Sampling was conducted in December, May, and August over a two-year period. The highest levels of mercury were detected in amphipods, with total mercury levels often in excess of 20 ppm. Bioaccumulation pathways of mercury in invertebrates of the Okefenokee are probably complex; despite being larger and higher in the food chain, levels in odonates and crayfish were much lower than in amphipods. Mercury levels in invertebrates varied temporally with the highest levels detected in May. There was a lack of spatial variation in mercury levels which is consistent with aerial deposition of mercury. - This study measured mercury levels in invertebrates and found the highest levels in amphipods

  8. Assessment of mobility and bioavailability of mercury compounds in sewage sludge and composts.

    Science.gov (United States)

    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.

  9. Water displacement mercury pump

    Science.gov (United States)

    Nielsen, M.G.

    1984-04-20

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

  10. Interspecific and intraspecific variation in selenium:mercury molar ratios in saltwater fish from the Aleutians: Potential protection on mercury toxicity by selenium

    Science.gov (United States)

    Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Donio, Mark; Pittfield, Taryn

    2014-01-01

    A number of factors affect the consumption risk from mercury in fish, including mercury levels, seasonal patterns of mercury concentrations, human consumption patterns, and sensitive populations (e.g. pregnant women, fetuses, young children, and yet unknown genetic factors). Recently the protective effects of selenium on methylmercury toxicity have been publicized, particularly for saltwater fish. We examine levels of mercury and selenium in several species of fish and seabirds from the Aleutians (Alaska), determine selenium:mercury molar ratios, and examine species-specific and individual variation in the ratios as a means of exploring the use of the ratio in risk assessment and risk management. Variation among species was similar for mercury and selenium. There was significant inter-specific and intraspecific variation in selenium:mercury molar ratios for fish, and for birds. The mean selenium:mercury molar ratios for all fish and bird species were above 1, meaning there was an excess of selenium relative to mercury. It has been suggested that an excess of selenium confers some protective advantage for salt water fish, although the degree of excess necessary is unclear. The selenium:mercury molar ratio was significantly correlated negatively with total length for most fish species, but not for dolly varden. Some individuals of Pacific cod, yellow irish lord, rock greenling, Pacific halibut, dolly varden, and to a lesser extent, flathead sole, had selenium:mercury ratios below 1. No bird muscle had an excess of mercury (ratio below 1), and only glaucous-winged gull and pigeon guillemot had ratios between 1 and 5. There was a great deal of variation in selenium:mercury molar ratios within fish species, and within bird species, making it difficult and impractical to use these ratios in risk assessment or management, for fish advisories, or for consumers, particularly given the difficulty of interpreting the ratios. PMID:22664537

  11. Mercury and cortisol in Western Hudson Bay polar bear hair.

    Science.gov (United States)

    Bechshoft, T; Derocher, A E; Richardson, E; Mislan, P; Lunn, N J; Sonne, C; Dietz, R; Janz, D M; St Louis, V L

    2015-08-01

    Non-invasive methods of assessing animal health and life history are becoming increasingly popular in wildlife research; hair samples from polar bears (Ursus maritimus), are being used to study an ever broader range of anthropogenic and endocrine compounds. A number of contaminants are known to disrupt endocrine function in polar bears. However, the relationship between mercury and cortisol remains unknown, although mercury is an endocrine disruptor in other species. Here, we examine the relationship between concentrations of cortisol and total mercury (THg) analyzed in guard hair from 378 polar bears (184 females, 194 males) sampled in Western Hudson Bay, 2004-2012. The difference in mean cortisol concentration between female (0.8 ± 0.6 pg/mg) and male (0.7 ± 0.5 pg/mg) polar bears bordered on significance (p = 0.054). However, mean mercury concentration was significantly greater (p = 0.009) in females (4.7 ± 1.4 μg/g) than males (4.3 ± 1.2 μg/g). Hair cortisol in males was significantly influenced by mercury, age, and fatness, as well as interactions between mercury and year, mercury and fatness, and year and fatness (all: p polar bears.

  12. Mercury Levels in Locally Manufactured Mexican Skin-Lightening Creams

    Directory of Open Access Journals (Sweden)

    Luz O. Leal

    2011-06-01

    Full Text Available Mercury is considered one of the most toxic elements for plants and animals. Nevertheless, in the Middle East, Asia and Latin America, whitening creams containing mercury are being manufactured and purchased, despite their obvious health risks. Due to the mass distribution of these products, this can be considered a global public health issue. In Mexico, these products are widely available in pharmacies, beauty aid and health stores. They are used for their skin lightening effects. The aim of this work was to analyze the mercury content in some cosmetic whitening creams using the cold vapor technique coupled with atomic absorption spectrometry (CV-AAS. A total of 16 skin-lightening creams from the local market were investigated. No warning information was noted on the packaging. In 10 of the samples, no mercury was detected. The mercury content in six of the samples varied between 878 and 36,000 ppm, despite the fact that the U.S. Food and Drug Administration (FDA has determined that the limit for mercury in creams should be less than 1 ppm. Skin creams containing mercury are still available and commonly used in Mexico and many developing countries, and their contents are poorly controlled.

  13. Emissions of mercury from the power sector in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Zysk, J.; Wyrwa, A.; Pluta, M. [AGH University of Science & Technology, Krakow (Poland). Faculty of Energy & Fuels

    2011-01-15

    Poland belongs to the European Union countries with the highest mercury emissions. This is mainly related to coal combustion. This paper presents estimates of mercury emissions from power sector in Poland. In this work, the bottom-up approach was applied and over 160 emission point sources were analysed. For each, the characteristics of the whole technological chain starting from fuel quality, boiler type as well as emission controls were taken into account. Our results show that emissions of mercury from brown coal power plants in 2005 were nearly four times greater than those of hard coal power plants. These estimates differ significantly from national statistics and some possible reasons are discussed. For the first time total mercury emissions from the Polish power sector were differentiated into its main atmospheric forms: gaseous elemental (GEM), reactive gaseous (RGM) and particulate-bound mercury. Information on emission source location and the likely vertical distribution of mercury emissions, which can be used in modelling of atmospheric dispersion of mercury is also provided.

  14. Emissions of mercury from the power sector in Poland

    Science.gov (United States)

    Zyśk, J.; Wyrwa, A.; Pluta, M.

    2011-01-01

    Poland belongs to the European Union countries with the highest mercury emissions. This is mainly related to coal combustion. This paper presents estimates of mercury emissions from power sector in Poland. In this work, the bottom-up approach was applied and over 160 emission point sources were analysed. For each, the characteristics of the whole technological chain starting from fuel quality, boiler type as well as emission controls were taken into account. Our results show that emissions of mercury from brown coal power plants in 2005 were nearly four times greater than those of hard coal power plants. These estimates differ significantly from national statistics and some possible reasons are discussed. For the first time total mercury emissions from the Polish power sector were differentiated into its main atmospheric forms: gaseous elemental (GEM), reactive gaseous (RGM) and particulate-bound mercury. Information on emission source location and the likely vertical distribution of mercury emissions, which can be used in modelling of atmospheric dispersion of mercury is also provided.

  15. Atmospheric mercury concentrations in the basin of the amazon, Brazil.

    Science.gov (United States)

    Hachiya, N; Takizawa, Y; Hisamatsu, S; Abe, T; Abe, Y; Motohashi, Y

    1998-01-01

    A wide regional mercury pollution in Amazon, Brazil is closely associated with goldmining that has been carried out in the basin of tributaries of the Amazon since the eighteenth century. Possible involvement has been discussed on atmospheric circulation in distributing the volatile pollutant. We developed a portable air sampler for the collection of mercury compounds and determined atmospheric mercury concentrations at several sites in Brazil including the basin of the Amazon tributaries. The mean concentration of total mercury was between 9.1 and 14.0 ng/m(3) in the basin of the Uatumã River located in the tropical rain forest far from goldmining sites and from urbanized area. These mercury levels exceeded the background level previously reported in rural area and, furthermore, were higher than concentrations observed in Rio de Janeiro and in Manaus that were compatible with the reference values for urban area. Mercury concentrations were also determined in gold refineries in the basin of the Tapajos River, and detected at a significant but not a health deteriorating level. Although only preliminary data were available, the present observations were in favor of the hypothesis that mercury is distributed widely by long distant transport by the atmospheric circulation after released at gold mining sites.

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

    Directory of Open Access Journals (Sweden)

    Jong Suk Park

    2017-01-01

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

  17. Isotopic Fractionation of Mercury in Great Lakes Precipitation

    Science.gov (United States)

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

    2009-12-01

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

  18. Mercury in Nelson's Sparrow subspecies at breeding sites.

    Directory of Open Access Journals (Sweden)

    Virginia L Winder

    Full Text Available BACKGROUND: Mercury is a persistent, biomagnifying contaminant that can cause negative effects on ecosystems. Marshes are often areas of relatively high mercury methylation and bioaccumulation. Nelson's Sparrows (Ammodramus nelsoni use marsh habitats year-round and have been documented to exhibit tissue mercury concentrations that exceed negative effects thresholds. We sought to further characterize the potential risk of Nelson's Sparrows to mercury exposure by sampling individuals from sites within the range of each of its subspecies. METHODOLOGY/PRINCIPAL FINDINGS: From 2009 to 2011, we captured adult Nelson's Sparrows at sites within the breeding range of each subspecies (A. n. nelsoni: Grand Forks and Upham, North Dakota; A. n. alterus: Moosonee, Ontario; and A. n. subvirgatus: Grand Manan Island, New Brunswick and sampled breast feathers, the first primary feather (P1, and blood for total mercury analysis. Mean blood mercury in nelsoni individuals captured near Grand Forks ranged from 0.84 ± 0.37 to 1.65 ± 1.02 SD ppm among years, between 2.0 and 4.9 times as high as concentrations at the other sites (P<0.01. Breast feather mercury did not vary among sites within a given sampling year (site means ranged from 0.98 ± 0.69 to 2.71 ± 2.93 ppm. Mean P1 mercury in alterus (2.96 ± 1.84 ppm fw was significantly lower than in any other sampled population (5.25 ± 2.24-6.77 ± 3.51 ppm; P ≤ 0.03. CONCLUSIONS/SIGNIFICANCE: Our study further characterized mercury in Nelson's Sparrows near Grand Forks; we documented localized and potentially harmful mercury concentrations, indicating that this area may represent a biological mercury hotspot. This finding warrants further research to determine if wildlife populations of conservation or recreational interest in this area may be experiencing negative effects due to mercury exposure. We present preliminary conclusions about the risk of each sampled population to mercury exposure.

  19. Mercury exposure in Ireland

    DEFF Research Database (Denmark)

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

    2014-01-01

    of a study to Coordinate and Perform Human Biomonitoring on a European Scale (DEMOCOPHES) pilot biomonitoring study. METHODS: Hair mercury concentrations were determined from a convenience sample of 120 mother/child pairs. Mothers also completed a questionnaire. Rigorous quality assurance within DEMOCOPHES...... guaranteed the accuracy and international comparability of results. RESULTS: Mercury was detected in 79.2% of the samples from mothers, and 62.5% of children's samples. Arithmetic mean levels in mothers (0.262 µg/g hair) and children (0.149 µg /g hair) did not exceed the US EPA guidance value. Levels were...

  20. Mercury CEM Calibration

    Energy Technology Data Exchange (ETDEWEB)

    John Schabron; Joseph Rovani; Mark Sanderson

    2008-02-29

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

  1. Ecological and physiological parameters of mercury and cesium-137 accumulation in the raccoon

    International Nuclear Information System (INIS)

    Davis, A.H.

    1981-01-01

    Raccoons from 4 regions in the southeastern Coastal Plain were evaluated for mercury content. Mercury content of hair when used as an indicator of total body mercury content was significantly different among 3 of the 4 areas: Okefenokee Swamp, Eglin Air Force Base, and Sapelo Island on the Georgia Coast. Raccoons from Echols County Georgia were not significantly different from those of the Okefenokee. Mercury in the liver and kidney was significantly different between Okefenokee and Sapelo. There was a strong correlation between the age of the raccoon and the mercury in hair, with older animals having higher concentrations. This relationship was also valid for most other tissues. There was evidence that mercury content in some tissues was correlated with the season and the body condition of the raccoon. Mercury was not transferred through the placenta to the fetal raccoons. There was a strong relationship of mercury content to raccoon behavioral characteristics. Raccoon body weight was slightly different between the areas studied. Cesium-137 values in raccoons were significantly different between the Okefenokee and Sapelo Island. Cesium-137 content was correlated with raccoon age, body weight, and mercury content. Generally non-detectable levels of chlorinated hydrocarbons and PCB were found in Okefenokee raccoons. Mercury concentrations in crayfish were generally low but probably of importance in the raccoon food chain. The biological half life of mercury in brain, gonad, pancreas, spleen, heart, and lung was approximately 52 days. The half-life of mercury in muscle was 35 days. Mercury content of hair, liver, and kidney decreased at very slow rates, with biological half lives of 229, 108, and 138 days. This was probably due to the role of these tissues in clearance of mercury from the body, and to the molting pattern of raccoon hair

  2. Health and environmental impact of mercury in the Philippines using nuclear techniques. Highlights and achievements

    International Nuclear Information System (INIS)

    Cortes-Maramba, Nelia

    2002-01-01

    This is the first comprehensive health evaluation made by the Department of Health of the mining community's exposure to total and methyl mercury. Previous studies have mainly focused more on the health risks associated with occupational exposure to mercury. Other sources of mercury exposure such as diet and other environmental media was not investigated and the population studied did not include high risk groups such as pregnant women and children

  3. [Mercury in the hair of pregnant and lactating Chilean mothers].

    Science.gov (United States)

    Bruhn, C G; Rodríguez, A A; Barrios, C A; Jaramillo, V H; Gras, N T; Becerra, J; Núñez, E; Reyes, O C

    1995-11-01

    Mercury-containing industrial waste has been released into the coastal waters of the Eighth Region of Chile for around two decades. This study, carried out from 1991 to 1993, sought to measure mercury concentrations in the hair of pregnant and lactating women from villages near the coast and in the interior of the region in order to examine the relationship between the concentration of mercury and seafood consumption. The survey questionnaire used in 1991 to determine seafood consumption did not ask about the frequency of consumption of fish, shellfish, and algae but only whether the women who were pregnant or breast-feeding consumed a minimum of one fish-based meal per week. The questionnaire used in 1992 and 1993 asked about the daily and weekly consumption of seafood in general (fish, shellfish, and algae). Spectrophotometry was used to determine the total mercury concentration in samples of 100 mg of hair from 153 pregnant and lactating women in 11 fishing villages of the Eighth Region where seafood is regularly consumed. None of the women had occupational exposure to mercury. Total mercury concentration was also determined in hair samples from a control group composed of 26 pregnant and lactating women from Pinto and El Carmen, villages in the interior of the same region where seafood was rarely eaten. The arithmetic mean of the total mercury concentration in hair was 1.81 mg/kg of body weight for the study group (standard deviation [SD] 1.52) and 0.42 mg/kg for the control group (SD 0.15)--a statistically significant difference (P mercury concentration in hair was significantly higher in women who indicated that they ate fish seven or more times per week; in those who said they ate fish, shellfish, or algae five or more times per week; and in those who had lived 20 or more years in their village. No statistically significant differences were found when the results were analyzed by age.

  4. Health and environmental impact of mercury in the Philippines using nuclear techniques

    International Nuclear Information System (INIS)

    Cortex-Maramba, Nelia; Trinidad Francisco-Rivera, Ana; Manglicmot, Ailyn; Santos, Flora; Akagi, Hirokatsu

    2001-01-01

    Artisanal gold mining activities using mercury has proliferated in various parts of the country since the early 1980's. In Southern Philippines, it is estimated that a small-scale gold processor utilizes one kilogram of mercury every week or an average of fifty-two kgs./yr. Production is estimated at 30 kilograms of gold per day. It has been estimated that 140 tons of mercury flux have been dumped directly into the river systems from small-scale gold mining operations in one of the gold rush areas in the country. Small-scale mining operations have affected tributaries and water systems in the country that also relies heavily on fishing as a source of livelihood as well as the daily food fare among the low-income sectors in the area. Aside from this, cattle livestock and agricultural production have also been affected by these mining activities because of contamination of the irrigation and water systems. Presently, environmental and health monitoring conducted by several government agencies in the recent past were limited to the determination of total mercury only. Previous studies undertaken focused mainly on the exposure of adults and workers to mercury during mining/processing operations. Environmental quality monitoring showed total mercury sediment levels ranged from 0.55 ug/g dry weight while water samples from river systems exhibited mercury levels from 0.0728-0.0784 ppb. Fish samples collected showed levels ranging from 1.07-438.8 ppb for total mercury and 0.71-377.18 ppb for methyl mercury. Methyl mercury content in fish ranged from 56-99%. Laboratory results showed that total mercury hair samples in schoolchildren ranged from 0.278-20.393 ppm while methyl mercury levels were from 0.191-18.469 ppm. Methyl mercury represented 45.96%-99.81% of the total mercury levels in hair. Total blood mercury levels ranged from 0.757-56.88 ppb while methyl mercury blood levels ranged from 1.36-46.73 ppb. Summary of physical examination results showed that predominant

  5. Method and apparatus for sampling atmospheric mercury

    Science.gov (United States)

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

    1976-01-20

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

  6. Seasonal variations of ambient air mercury species nearby an airport

    Science.gov (United States)

    Fang, Guor-Cheng; Tsai, Kai-Hsiang; Huang, Chao-Yang; Yang, Kuang-Pu Ou; Xiao, You-Fu; Huang, Wen-Chuan; Zhuang, Yuan-Jie

    2018-04-01

    This study focuses on the collection of ambient air mercury species (total gaseous mercury (TGM), reactive gaseous mercury (RGM), gaseous element mercury (GEM) and particulate bound mercury (PBM) pollutants at airport nearby sampling site during the year of Apr. 2016 to Mar. 2017 by using Four-stage gold amalgamation and denuder. The results indicated that the average TGM, RGM and GEM concentrations were 5.04 ± 2.43 ng/m3, 29.58 ± 80.54 pg/m3, 4.70 ± 2.63 ng/m3, respectively during the year of Apr. 2016 to Mar. 2017 (n = 49) period at this airport sampling site nearby. In addition, the results also indicated that the average PBM concentrations in TSP and PM2.5 were 0.35 ± 0.08 ng/m3 and 0.09 ± 0.03 ng/m3, respectively. And the average PBM in TSP concentrations order follows as summer > autumn > spring > winter, while the average PBM in PM2.5 concentrations order follows as spring > summer > winter > autumn. Moreover, the average TGM, RGM and GEM concentrations order follow as spring > summer > autumn > winter. Finally, the Asian continent has the highest average mercury species concentrations (TGM, RGM, GEM and PBM) when compared with the American and European continents, and the average mercury species concentrations (TGM, RGM, GEM and PBM) displayed declined trends for North America (United States and Canada) and Europe (Spain, Sweden and Southern Baltic) during the years of 2004-2014. Also noteworthy is that the average mercury species concentrations (TGM, RGM, GEM) displayed increasing trends in China and Taiwan during the years of 2008-2016. Japan and Korea are the only two exceptions. Those above two countries mercury species concentrations displayed decreasing trends during years of 2008-2015.

  7. Mercury in breast milk - a health hazard for infants in gold mining areas?

    Science.gov (United States)

    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.

  8. BEHAVIOR OF MERCURY DURING DWPF CHEMICAL PROCESS CELL PROCESSING

    Energy Technology Data Exchange (ETDEWEB)

    Zamecnik, J.; Koopman, D.

    2012-04-09

    retention of mercury in the slurry. Both recovery of mercury in the offgas system and removal (segregation + recovery) from the slurry correlate with slurry consistency. Higher slurry consistency results in better retention of Hg in the slurry (less segregation) and better recovery in the offgas system, but the relationships of recovery and retention with consistency are sludge dependent. Some correlation with slurry yield stress and acid stoichiometry was also found. Better retention of mercury in the slurry results in better recovery in the offgas system because the mercury in the slurry is stripped more easily than the segregated mercury at the bottom of the vessel. Although better retention gives better recovery, the time to reach a particular slurry mercury content (wt%) is longer than if the retention is poorer because the segregation is faster. The segregation of mercury is generally a faster process than stripping. The stripping factor (mass of water evaporated per mass of mercury stripped) of mercury at the start of boiling were found to be less than 1000 compared to the assumed design basis value of 750 (the theoretical factor is 250). However, within two hours, this value increased to at least 2000 lb water per lb Hg. For runs with higher mercury recovery in the offgas system, the stripping factor remained around 2000, but runs with low recovery had stripping factors of 4000 to 40,000. DWPF data shows similar trends with the stripping factor value increasing during boiling. These high values correspond to high segregation and low retention of mercury in the sludge. The stripping factor for a pure Hg metal bead in water was found to be about 10,000 lb/lb. About 10-36% of the total Hg evaporated in a SRAT cycle was refluxed back to the SRAT during formic acid addition and boiling. Mercury is dissolved as a result of nitric acid formation from absorption of NO{sub x}. The actual solubility of dissolved mercury in the acidic condensate is about 100 times higher than

  9. Evaluation of Background Mercury Concentrations in the SRS Groundwater System

    International Nuclear Information System (INIS)

    Looney, B.B.

    1999-01-01

    Mercury analyses associated with the A-01 Outfall have highlighted the importance of developing an understanding of mercury in the Savannah River Site groundwater system and associated surface water streams. This activity is critical based upon the fact that the EPA Ambient Water Quality Criteria (AWQC) for this constituent is 0.012mg/L, a level that is well below conventional detection limits of 0.1 to 0.2 mg/L. A first step in this process is obtained by utilizing the existing investment in groundwater mercury concentrations (20,242 records) maintained in the SRS geographical information management system (GIMS) database. Careful use of these data provides a technically defensible initial estimate for total recoverable mercury in background and contaminated SRS wells

  10. Evaluation of mercury contamination in Smilax myosotiflora herbal preparations.

    Science.gov (United States)

    Ang, Hooi-Hoon; Lee, Kheng-Leng

    2007-01-01

    The DCA (Drug Control Authority) of Malaysia implemented phase 3 registration of traditional medicines in January 1992 with special emphasis on the quality, efficacy, and safety of all dosage forms of these medicines. For this reason, a total of 100 herbal products containing Smilax myosotiflora were purchased in the Malaysian market and analyzed for mercury content, as mercury is a recognized reproductive toxicant. The products were analyzed using cold vapor atomic absorption spectrophotometry. It was found that 89% of the above products do not exceed 0.5 ppm of mercury. Heavy metal poisoning such as mercury has been associated with traditional medicines. Therefore, it is important that doctors and health care practitioners are aware of these risks and finding ways to minimize them, including questions pertaining to the use of these remedies during the routine taking of a patient's history.

  11. Mercury levels in eggs, embryos, and neonates of Trachemys callirostris (Testudines, Emydidae)

    International Nuclear Information System (INIS)

    Rendon Valencia, Beatriz; Zapata, Lina M; Bock, Brian C; Paez, Vivian P; Palacio, Jaime A.

    2014-01-01

    We quantified total mercury concentrations in eggshells, egg yolks, and embryos from 16 nests of the Colombian slider (Trachemys callirostris). Nests were collected in different stages of development, but estimated time of incubation in natural substrates was not correlated with mercury levels in the eggs, suggesting that mercury was not absorbed from the substrate, but more likely passed on to the embryos during folliculogenesis by the reproductive females who had bioaccumulated the mercury from environmental sources. Mean mercury concentrations were higher in embryos than in eggshells or egg yolks, indicating that embryos also bioaccumulate mercury present in other egg tissues. Intra-clutch variation in egg yolk mercury concentrations was relatively high. Egg yolk mercury concentrations were not associated with any of the fitness proxies we quantified for the nests (hatching success rates, initial neonate sizes and first-month juvenile growth rates). After five months of captive rearing in a mercury-free laboratory environment, 86 % of the juveniles had eliminated the mercury from their tissues.

  12. Cadmium, mercury and selenium concentrations in mink (Mustela vison) from Yukon, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Gamberg, Mary [Gamberg Consulting, Box 10460, Whitehorse, Yukon, Y1A 7A1 (Canada)]. E-mail: mary.gamberg@northwestel.net; Boila, Gail [Freshwater Institute, Fisheries and Oceans Canada, 501 University Crescent, Winnipeg, MB, R3T 2N6 (Canada); Stern, Gary [Freshwater Institute, Fisheries and Oceans Canada, 501 University Crescent, Winnipeg, MB, R3T 2N6 (Canada); Roach, Patrick [Department of Indian and Northern Affairs, Suite 300, 300 Main Street, Whitehorse, Yukon, Y1A 2B5 (Canada)

    2005-12-01

    Mercury (total and methyl), cadmium and selenium concentrations were measured in liver, kidney and brain tissue from mink trapped from the Yukon Territory from 2001-2002. None of these metals was found at levels of toxicological concern. Total mercury averaged 0.66, 0.92 and 0.22 {mu}g g{sup -1} in mink kidney, liver and brain tissue respectively, while methyl mercury averaged 0.77, 0.85 and 0.21 {mu}g g{sup -1} in the same tissues. Selenium averaged 2.07, 1.40 and 0.39 {mu}g g{sup -1} in mink kidney, liver and brain tissue, while cadmium was only measured in kidneys and averaged 0.22 {mu}g g{sup -1}. All element concentrations are presented on a wet weight basis. Concentrations of total mercury in all tissues were significantly higher in female than male mink, possibly reflecting proportionally greater food consumption by the smaller females. Total mercury concentrations were inversely related to the proportion of mercury present as methylmercury, and positively related to concentrations of selenium, consistent with increasing demethylation of methylmercury, and the formation of mercuric selenide as total concentrations of mercury increased. This relationship was seen most strongly in mink liver, less so in kidneys and not at all in brains where most of the mercury was maintained in the methyl form. There did not appear to be any geographical areas in which mink had obviously higher concentrations of mercury, and there was frequently a relatively large range of mercury levels found in mink from a given trapline. Mink diet may be a factor in this variation. Local environmental levels of cadmium were not reflected in cadmium concentrations in mink tissues. Mercury, cadmium and selenium do not appear to constitute environmental hazards to mink in the Yukon.

  13. Cadmium, mercury and selenium concentrations in mink (Mustela vison) from Yukon, Canada

    International Nuclear Information System (INIS)

    Gamberg, Mary; Boila, Gail; Stern, Gary; Roach, Patrick

    2005-01-01

    Mercury (total and methyl), cadmium and selenium concentrations were measured in liver, kidney and brain tissue from mink trapped from the Yukon Territory from 2001-2002. None of these metals was found at levels of toxicological concern. Total mercury averaged 0.66, 0.92 and 0.22 μg g -1 in mink kidney, liver and brain tissue respectively, while methyl mercury averaged 0.77, 0.85 and 0.21 μg g -1 in the same tissues. Selenium averaged 2.07, 1.40 and 0.39 μg g -1 in mink kidney, liver and brain tissue, while cadmium was only measured in kidneys and averaged 0.22 μg g -1 . All element concentrations are presented on a wet weight basis. Concentrations of total mercury in all tissues were significantly higher in female than male mink, possibly reflecting proportionally greater food consumption by the smaller females. Total mercury concentrations were inversely related to the proportion of mercury present as methylmercury, and positively related to concentrations of selenium, consistent with increasing demethylation of methylmercury, and the formation of mercuric selenide as total concentrations of mercury increased. This relationship was seen most strongly in mink liver, less so in kidneys and not at all in brains where most of the mercury was maintained in the methyl form. There did not appear to be any geographical areas in which mink had obviously higher concentrations of mercury, and there was frequently a relatively large range of mercury levels found in mink from a given trapline. Mink diet may be a factor in this variation. Local environmental levels of cadmium were not reflected in cadmium concentrations in mink tissues. Mercury, cadmium and selenium do not appear to constitute environmental hazards to mink in the Yukon

  14. Mercury in San Francisco Bay forage fish

    Energy Technology Data Exchange (ETDEWEB)

    Greenfield, Ben K., E-mail: ben@sfei.or [San Francisco Estuary Institute, 7770 Pardee Lane, Oakland, CA 94621 (United States); Jahn, Andrew, E-mail: andyjahn@mac.co [1000 Riverside Drive, Ukiah, CA 95482 (United States)

    2010-08-15

    In the San Francisco Estuary, management actions including tidal marsh restoration could change fish mercury (Hg) concentrations. From 2005 to 2007, small forage fish were collected and analyzed to identify spatial and interannual variation in biotic methylmercury (MeHg) exposure. The average whole body total Hg concentration was 0.052 {mu}g g{sup -1} (wet-weight) for 457 composite samples representing 13 fish species. MeHg constituted 94% of total Hg. At a given length, Hg concentrations were higher in nearshore mudflat and wetland species (Clevelandia ios, Menidia audens, and Ilypnus gilberti), compared to species that move offshore (e.g., Atherinops affinis and Lepidogobius lepidus). Gut content analysis indicated similar diets between Atherinops affinis and Menidia audens, when sampled at the same locations. Hg concentrations were higher in sites closest to the Guadalupe River, which drains a watershed impacted by historic Hg mining. Results demonstrate that despite differences among years and fish species, nearshore forage fish exhibit consistent Hg spatial gradients. - Total mercury in estuarine forage fish varies with species, habitat, and proximity to a historic mercury mine.

  15. Mercury in San Francisco Bay forage fish

    International Nuclear Information System (INIS)

    Greenfield, Ben K.; Jahn, Andrew

    2010-01-01

    In the San Francisco Estuary, management actions including tidal marsh restoration could change fish mercury (Hg) concentrations. From 2005 to 2007, small forage fish were collected and analyzed to identify spatial and interannual variation in biotic methylmercury (MeHg) exposure. The average whole body total Hg concentration was 0.052 μg g -1 (wet-weight) for 457 composite samples representing 13 fish species. MeHg constituted 94% of total Hg. At a given length, Hg concentrations were higher in nearshore mudflat and wetland species (Clevelandia ios, Menidia audens, and Ilypnus gilberti), compared to species that move offshore (e.g., Atherinops affinis and Lepidogobius lepidus). Gut content analysis indicated similar diets between Atherinops affinis and Menidia audens, when sampled at the same locations. Hg concentrations were higher in sites closest to the Guadalupe River, which drains a watershed impacted by historic Hg mining. Results demonstrate that despite differences among years and fish species, nearshore forage fish exhibit consistent Hg spatial gradients. - Total mercury in estuarine forage fish varies with species, habitat, and proximity to a historic mercury mine.

  16. Mercury Exposure and Heart Diseases

    Science.gov (United States)

    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

  17. Mercury Exposure and Heart Diseases.

    Science.gov (United States)

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

    2017-01-12

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

  18. Mercury Exposure and Heart Diseases

    Directory of Open Access Journals (Sweden)

    Giuseppe Genchi

    2017-01-01

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

  19. Mercury and selenium levels, and selenium:mercury molar ratios of brain, muscle and other tissues in bluefish (Pomatomus saltatrix) from New Jersey, USA

    Science.gov (United States)

    Burger, Joanna; Jeitner, Christian; Donio, Mark; Pittfield, Taryn; Gochfeld, Michael

    2015-01-01

    A number of contaminants affect fish health, including mercury and selenium, and the selenium: mercury molar ratio. Recently the protective effects of selenium on methylmercury toxicity have been publicized, particularly for consumption of saltwater fish. Yet the relative ameliorating effects of selenium on toxicity within fish have not been examined, nor has the molar ratio in different tissues, (i.e. brain). We examined mercury and selenium levels in brain, kidney, liver, red and white muscle, and skin and scales in bluefish (Pomatomus saltatrix) from New Jersey to determine whether there were toxic levels of either metal, and we computed the selenium: mercury molar ratios by tissues. Total mercury averaged 0.32 ± 0.02 ppm wet weight in edible muscle and 0.09 ± 0.01 ppm in brain. Selenium concentration averaged 0.37 ± 0.03 in muscle and 0.36 ± 0.03 ppm in brain. There were significant differences in levels of mercury, selenium, and selenium: mercury molar ratios, among tissues. Mercury and selenium levels were correlated in kidney and skin/scales. Mercury levels were highest in kidney, intermediate in muscle and liver, and lowest in brain and skin/scales; selenium levels were also highest in kidney, intermediate in liver, and were an order of magnitude lower in the white muscle and brain. Mercury levels in muscle, kidney and skin/scales were positively correlated with fish size (length). Selenium levels in muscle, kidney and liver were positively correlated with fish length, but in brain; selenium levels were negatively correlated with fish length. The selenium: mercury molar ratio was negatively correlated with fish length for white muscle, liver, kidney, and brain, particularly for fish over 50 cm in length, suggesting that older fish experience less protective advantages of selenium against mercury toxicity than smaller fish, and that consumers of bluefish similarly receive less advantage from eating larger fish. PMID:23202378

  20. Advanced Emissions Control Development Program: Mercury Control

    International Nuclear Information System (INIS)

    Evans, A.P.; Redinger, K.W.; Holmes, M.J.

    1997-07-01

    selenium and mercury, the majority of trace elements are well controlled due to their association with the particulate phase of flue gas. Reflecting the current focus of the US EPA and state environmental agencies on mercury as a potential candidate for regulation, the project specifically targets the measurement and control of mercury species. This paper discusses the results of testing on the quantity and species distribution of mercury while firing Ohio high-sulfur coal to assess the mercury emissions control potential of conventional SO 2 and particulate control systems. Results from recent AECDP tests are presented and two alternative mercury speciation methods are compared. The AECDP results clearly show that higher total mercury control efficiency can be achieved with a wet FGD scrubber than recently reported in the interim final US EPA report on HAP emissions from fossil-fired electric utility steam generating units

  1. Mercury in Nelson's Sparrow Subspecies at Breeding Sites

    Science.gov (United States)

    Winder, Virginia L.; Emslie, Steven D.

    2012-01-01

    Background Mercury is a persistent, biomagnifying contaminant that can cause negative effects on ecosystems. Marshes are often areas of relatively high mercury methylation and bioaccumulation. Nelson's Sparrows (Ammodramus nelsoni) use marsh habitats year-round and have been documented to exhibit tissue mercury concentrations that exceed negative effects thresholds. We sought to further characterize the potential risk of Nelson's Sparrows to mercury exposure by sampling individuals from sites within the range of each of its subspecies. Methodology/Principal Findings From 2009 to 2011, we captured adult Nelson's Sparrows at sites within the breeding range of each subspecies (A. n. nelsoni: Grand Forks and Upham, North Dakota; A. n. alterus: Moosonee, Ontario; and A. n. subvirgatus: Grand Manan Island, New Brunswick) and sampled breast feathers, the first primary feather (P1), and blood for total mercury analysis. Mean blood mercury in nelsoni individuals captured near Grand Forks ranged from 0.84±0.37 to 1.65±1.02 SD ppm among years, between 2.0 and 4.9 times as high as concentrations at the other sites (Pmercury did not vary among sites within a given sampling year (site means ranged from 0.98±0.69 to 2.71±2.93 ppm). Mean P1 mercury in alterus (2.96±1.84 ppm fw) was significantly lower than in any other sampled population (5.25±2.24–6.77±3.51 ppm; P≤0.03). Conclusions/Significance Our study further characterized mercury in Nelson's Sparrows near Grand Forks; we documented localized and potentially harmful mercury concentrations, indicating that this area may represent a biological mercury hotspot. This finding warrants further research to determine if wildlife populations of conservation or recreational interest in this area may be experiencing negative effects due to mercury exposure. We present preliminary conclusions about the risk of each sampled population to mercury exposure. PMID:22384194

  2. Formation of nanocolloidal metacinnabar in mercury-DOM-sulfide systems

    Science.gov (United States)

    Gerbig, Chase A.; Kim, Christopher S.; Stegemeier, John P.; Ryan, Joseph N.; Aiken, George R.

    2011-01-01

    Direct determination of mercury (Hg) speciation in sulfide-containing environments is confounded by low mercury concentrations and poor analytical sensitivity. Here we report the results of experiments designed to assess mercury speciation at environmentally relevant ratios of mercury to dissolved organic matter (DOM) (i.e., structure (EXAFS) spectroscopy. Aqueous Hg(II) and a DOM isolate were equilibrated in the presence and absence of 100 μM total sulfide. In the absence of sulfide, mercury adsorption to the resin increased as the Hg:DOM ratio decreased and as the strength of Hg-DOM binding increased. EXAFS analysis indicated that in the absence of sulfide, mercury bonds with an average of 2.4 ± 0.2 sulfur atoms with a bond length typical of mercury-organic thiol ligands (2.35 Å). In the presence of sulfide, mercury showed greater affinity for the C18 resin, and its chromatographic behavior was independent of Hg:DOM ratio. EXAFS analysis showed mercury–sulfur bonds with a longer interatomic distance (2.51–2.53 Å) similar to the mercury–sulfur bond distance in metacinnabar (2.53 Å) regardless of the Hg:DOM ratio. For all samples containing sulfide, the sulfur coordination number was below the ideal four-coordinate structure of metacinnabar. At a low Hg:DOM ratio where strong binding DOM sites may control mercury speciation (1.9 nmol mg–1) mercury was coordinated by 2.3 ± 0.2 sulfur atoms, and the coordination number rose with increasing Hg:DOM ratio. The less-than-ideal coordination numbers indicate metacinnabar-like species on the nanometer scale, and the positive correlation between Hg:DOM ratio and sulfur coordination number suggests progressively increasing particle size or crystalline order with increasing abundance of mercury with respect to DOM. In DOM-containing sulfidic systems nanocolloidal metacinnabar-like species may form, and these species need to be considered when addressing mercury biogeochemistry.

  3. Mercury emissions from coal combustion in Silesia, analysis using geostatistics

    Science.gov (United States)

    Zasina, Damian; Zawadzki, Jaroslaw

    2015-04-01

    Data provided by the UNEP's report on mercury [1] shows that solid fuel combustion in significant source of mercury emission to air. Silesia, located in southwestern Poland, is notably affected by mercury emission due to being one of the most industrialized Polish regions: the place of coal mining, production of metals, stone mining, mineral quarrying and chemical industry. Moreover, Silesia is the region with high population density. People are exposed to severe risk of mercury emitted from both: industrial and domestic sources (i.e. small household furnaces). Small sources have significant contribution to total emission of mercury. Official and statistical analysis, including prepared for international purposes [2] did not provide data about spatial distribution of the mercury emitted to air, however number of analysis on Polish public power and energy sector had been prepared so far [3; 4]. The distribution of locations exposed for mercury emission from small domestic sources is interesting matter merging information from various sources: statistical, economical and environmental. This paper presents geostatistical approach to distibution of mercury emission from coal combustion. Analysed data organized in 2 independent levels: individual, bottom-up approach derived from national emission reporting system [5; 6] and top down - regional data calculated basing on official statistics [7]. Analysis, that will be presented, will include comparison of spatial distributions of mercury emission using data derived from sources mentioned above. Investigation will include three voivodeships of Poland: Lower Silesian, Opole (voivodeship) and Silesian using selected geostatistical methodologies including ordinary kriging [8]. References [1] UNEP. Global Mercury Assessment 2013: Sources, Emissions, Releases and Environmental Transport. UNEP Chemicals Branch, Geneva, Switzerland, 2013. [2] NCEM. Poland's Informative Inventory Report 2014. NCEM at the IEP-NRI, 2014. http

  4. MERCURY USAGE AND ALTERNATIVES IN THE ELECTRICAL AND ELECTRONICS INDUSTRIES

    Science.gov (United States)

    Many industries have already found alternatives for mercury or have greatly decreased mercury use. However, the unique electromechanical and photoelectric properties of mercury and mercury compounds have made replacement of mercury difficult in some applications. This study was i...

  5. Influence of the Sostanj coal-fired thermal power plant on mercury and methyl mercury concentrations in Lake Velenje, Slovenia

    Energy Technology Data Exchange (ETDEWEB)

    Kotnik, J.; Horvat, M.; Mandic, V.; Logar, M. [Department of Environmental Sciences, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

    2000-10-02

    Lake Velenje is located in one of the most polluted regions in Slovenia, the Salek Valley. The major source of pollution in the valley is the coal-fired thermal power plant in Sostanj (STPP, capacity 775 MW). It has five separate units. All units have electrostatic precipitators for fly ash removal. Unit 4 also has installed a wet flue gas desulfurisation system (FGD system). Total mercury (THg) concentrations were measured in lignite, slag and ash samples from the STPP. In flue gas, different mercury species (THg, MeHg, Hg{sup 2+}, Hg{sup 0}) were determined separately for unit 4 and unit 5 which use different flue gas cleaning technology. Mercury and methyl mercury (MeHg) concentrations were also measured in lake water at different depths, in inflow water, outflow water, rain, snow and lake sediments in order to establish the influence of the power plant on the lake. Most mercury emitted from the power plant is in the elemental form. The ratio between oxidised and elemental Hg depends on the flue gas cleaning technology. Mass balance calculations have been performed for the STPP. The results show that the major sources of mercury in Lake Velenje are wet deposition and lake inflows. Total and MeHg concentrations in the water column are very low and can be compared to other non-contaminated freshwater lakes in the world.

  6. Influence of the Sostanj coal-fired thermal power plant on mercury and methyl mercury concentrations in Lake Velenje, Slovenia

    Science.gov (United States)

    Kotnik; Horvat; Mandic; Logar

    2000-10-02

    Lake Velenje is located in one of the most polluted regions in Slovenia, the Salek Valley. The major source of pollution in the valley is the coal-fired thermal power plant in Sostanj (STPP, capacity 775 MW). It has five separate units. All units have electrostatic precipitators for fly ash removal. Unit 4 also has installed a wet flue gas desulfurisation system (FGD system). Total mercury (THg) concentrations were measured in lignite, slag and ash samples from the STPP. In flue gas, different mercury species (THg, MeHg, Hg2+, Hg0) were determined separately for unit 4 and unit 5 which use different flue gas cleaning technology. Mercury and methyl mercury (MeHg) concentrations were also measured in lake water at different depths, in inflow water, outflow water, rain, snow and lake sediments in order to establish the influence of the power plant on the lake. Most mercury emitted from the power plant is in the elemental form. The ratio between oxidised and elemental Hg depends on the flue gas cleaning technology. Mass balance calculations have been performed for the STPP. The results show that the major sources of mercury in Lake Velenje are wet deposition and lake inflows. Total and MeHg concentrations in the water column are very low and can be compared to other non-contaminated freshwater lakes in the world.

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

    Science.gov (United States)

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

    2008-07-04

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

  8. Changes in Hair Mercury Levels Among Women of Child-Bearing Age Following an Educational Intervention.

    Science.gov (United States)

    Raymond, Michelle; Christensen, Krista Y; Thompson, Brooke; Anderson, Henry

    2017-06-01

    Describe mercury exposures among women of childbearing age before and after an educational intervention. Women age 18 to 45 were recruited to participate in an educational intervention concerning fish consumption. Fish consumption habits and total mercury concentration in hair were assessed pre- and post-intervention. Regression models examined associations between mercury, fish consumption, and demographics. Overall, 234 women completed the study. On average, mercury concentrations increased by 0.01 ppm (parts per million) following the intervention, despite declines in fish consumption; however, women in the 90th percentile for mercury at baseline decreased concentrations significantly while maintaining high rates of fish consumption. Mercury concentrations were positively correlated with fish consumption and certain demographic characteristics. The intervention reached individuals most at-risk. Healthcare providers should discuss fish consumption habits with women to encourage consumption of low-risk fish, and identify women needing education and counseling.

  9. Recovery of mercury from acid waste residues

    Science.gov (United States)

    Greenhalgh, Wilbur O.

    1989-12-05

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

  10. Health Effects of Exposures to Mercury

    Science.gov (United States)

    ... IRIS database Top of Page Elemental (Metallic) Mercury Effects Exposures to metallic mercury most often occur when metallic ... poor performance on tests of mental function Higher exposures may also cause kidney effects, respiratory failure and death. Note that metallic mercury ...

  11. Mercury Poisoning Linked to Skin Products

    Science.gov (United States)

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

  12. Model analyses of atmospheric mercury: present air quality and effects of transpacific transport on the United States

    Science.gov (United States)

    Lei, H.; Liang, X.-Z.; Wuebbles, D. J.; Tao, Z.

    2013-11-01

    Atmospheric mercury is a toxic air and water pollutant that is of significant concern because of its effects on human health and ecosystems. A mechanistic representation of the atmospheric mercury cycle is developed for the state-of-the-art global climate-chemistry model, CAM-Chem (Community Atmospheric Model with Chemistry). The model simulates the emission, transport, transformation and deposition of atmospheric mercury (Hg) in three forms: elemental mercury (Hg(0)), reactive mercury (Hg(II)), and particulate mercury (PHg). Emissions of mercury include those from human, land, ocean, biomass burning and volcano related sources. Land emissions are calculated based on surface solar radiation flux and skin temperature. A simplified air-sea mercury exchange scheme is used to calculate emissions from the oceans. The chemistry mechanism includes the oxidation of Hg(0) in gaseous phase by ozone with temperature dependence, OH, H2O2 and chlorine. Aqueous chemistry includes both oxidation and reduction of Hg(0). Transport and deposition of mercury species are calculated through adapting the original formulations in CAM-Chem. The CAM-Chem model with mercury is driven by present meteorology to simulate the present mercury air quality during the 1999-2001 period. The resulting surface concentrations of total gaseous mercury (TGM) are then compared with the observations from worldwide sites. Simulated wet depositions of mercury over the continental United States are compared to the observations from 26 Mercury Deposition Network stations to test the wet deposition simulations. The evaluations of gaseous concentrations and wet deposition confirm a strong capability for the CAM-Chem mercury mechanism to simulate the atmospheric mercury cycle. The general reproduction of global TGM concentrations and the overestimation on South Africa indicate that model simulations of TGM are seriously affected by emissions. The comparison to wet deposition indicates that wet deposition patterns

  13. Efficiency of solvent extraction methods for the determination of methyl mercury in forest soils

    Energy Technology Data Exchange (ETDEWEB)

    Qian, J. [Department of Forest Ecology, Swedish University of Agricultural Sciences, Umeaa (Sweden); Dept. of Analytical Chemistry, Umeaa Univ. (Sweden); Skyllberg, U. [Department of Forest Ecology, Swedish University of Agricultural Sciences, Umeaa (Sweden); Tu, Q.; Frech, W. [Dept. of Analytical Chemistry, Umeaa Univ. (Sweden); Bleam, W.F. [Dept. of Soil Science, University of Wisconsin, Madison, WI (United States)

    2000-07-01

    Methyl mercury was determined by gas chromatography, microwave induced plasma, atomic emission spectrometry (GC-MIP-AES) using two different methods. One was based on extraction of mercury species into toluene, pre-concentration by evaporation and butylation of methyl mercury with a Grignard reagent followed by determination. With the other, methyl mercury was extracted into dichloromethane and back extracted into water followed by in situ ethylation, collection of ethylated mercury species on Tenax and determination. The accuracy of the entire procedure based on butylation was validated for the individual steps involved in the method. Methyl mercury added to various types of soil samples showed an overall average recovery of 87.5%. Reduced recovery was only caused by losses of methyl mercury during extraction into toluene and during pre-concentration by evaporation. The extraction of methyl mercury added to the soil was therefore quantitative. Since it is not possible to directly determine the extraction efficiency of incipient methyl mercury, the extraction efficiency of total mercury with an acidified solution containing CuSO{sub 4} and KBr was compared with high-pressure microwave acid digestion. The solvent extraction efficiency was 93%. For the IAEA 356 sediment certified reference material, mercury was less efficiently extracted and determined methyl mercury concentrations were below the certified value. Incomplete extraction could be explained by the presence of a large part of inorganic sulfides, as determined by x-ray absorption near-edge structure spectroscopy (XANES). Analyses of sediment reference material CRM 580 gave results in agreement with the certified value. The butylation method gave a detection limit for methyl mercury of 0.1 ng g{sup -1}, calculated as three times the standard deviation for repeated analysis of soil samples. Lower values were obtained with the ethylation method. The precision, expressed as RSD for concentrations 20 times

  14. Distribution and assessment of residual mercury from gold mining in Changbai Mountain Range Northeastern China

    Science.gov (United States)

    Meng, D.; Wang, N.; Ai, J. C.; Zhang, G.; Liu, X. J.

    2016-08-01

    Gold mining was first initiated in Jiapigou area, Huadian city of Northeastern China about 200 years ago. Before 2006, the mercury amalgamation technique was used in the gold mining process, which led to severe mercury contamination. The aim of this paper is to explore the influences of residual mercury on the environment media after eliminating the amalgamation process to extract gold. The mercury concentrations of the atmosphere and the soil were determined in autumn of 2011 and spring of 2012. The soil environmental quality was assessed by the index of geoaccumulation. The results indicated that the maximum value of gaseous mercury was 25ng•m-3 in autumn and 19.5ng•m-3 in spring; the maximum value of mercury in the soil was 2.06mg•kg-1 in autumn and 2.51mg•kg-1in spring. It can be seen that the peak concentrations of the gaseous mercury happened at the gold mine area and tailings, while the peak mercury concentrations in the soil were located at the places near the mining sites and the residential area in the valley. Furthermore, the regression analysis of the total mercury contents between the atmosphere and the soil showed a significant correlation, which indicated that there was certain circulation of the mercury between the regional atmosphere and soil. In general, after the elimination of the amalgamation technique in gold extraction, the distance to the mercury source, the special conditions of hilly weather and landforms and the mercury exchange flux are the main factors of mercury contamination.

  15. Seafood substitutions obscure patterns of mercury contamination in Patagonian toothfish (Dissostichus eleginoides or "Chilean sea bass".

    Directory of Open Access Journals (Sweden)

    Peter B Marko

    Full Text Available Seafood mislabeling distorts the true abundance of fish in the sea, defrauds consumers, and can also cause unwanted exposure to harmful pollutants. By combining genetic data with analyses of total mercury content, we have investigated how species substitutions and fishery-stock substitutions obscure mercury contamination in Patagonian toothfish (Dissostichus eleginoides, also known as "Chilean sea bass". Patagonian toothfish show wide variation in mercury concentrations such that consumers may be exposed to either acceptable or unacceptable levels of mercury depending on the geographic origins of the fish and the allowable limits of different countries. Most notably, stocks of Patagonian toothfish in Chile accumulate significantly more mercury than stocks closer to the South Pole, including the South Georgia/Shag Rocks stock, a fishery certified by the Marine Stewardship Council (MSC as sustainably fished. Consistent with the documented geography of mercury contamination, our analysis showed that, on average, retail fish labeled as MSC-certified Patagonian toothfish had only half the mercury of uncertified fish. However, consideration of genetic data that were informative about seafood substitutions revealed a complex pattern of contamination hidden from consumers: species substitutions artificially inflated the expected difference in mercury levels between MSC-certified and uncertified fish whereas fishery stock substitutions artificially reduced the expected difference in mercury content between MSC-certified and uncertified fish that were actually D. eleginoides. Among MSC-certified fish that were actually D. eleginoides, several with exogenous mtDNA haplotypes (i.e., not known from the certified fishery had mercury concentrations on par with uncertified fish from Chile. Overall, our analysis of mercury was consistent with inferences from the genetic data about the geographic origins of the fish, demonstrated the potential negative impact of

  16. Mercury speciation in thawed out and refrozen fish samples by gas chromatography coupled to inductively coupled plasma mass spectrometry and atomic fluorescence spectroscopy

    NARCIS (Netherlands)

    Krystek, Petra; Ritsema, Rob

    Different sub-sampling procedures were applied for the determination of mercury species (as total mercury Hg, methylmercury MeHg+ and inorganic mercury Hg2+) in frozen fish meat. Analyses were carried out by two different techniques. After the sample material was pre-treated by microwave digestion,

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

    International Nuclear Information System (INIS)

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

    2013-01-01

    In this case study, groundwater/surface water modeling was used to determine efficacy of stabilization in place with hydrologic isolation for remediation of mercury contaminated areas in the Upper East Fork Poplar Creek (UEFPC) Watershed in Oak Ridge, TN. The modeling simulates the potential for mercury in soil to contaminate groundwater above industrial use risk standards and to contribute to surface water contamination. The modeling approach is unique in that it couples watershed hydrology with the total mercury transport and provides a tool for analysis of changes in mercury load related to daily precipitation, evaporation, and runoff from storms. The model also allows for simulation of colloidal transport of total mercury in surface water. Previous models for the watershed only simulated average yearly conditions and dissolved concentrations that are not sufficient for predicting mercury flux under variable flow conditions that control colloidal transport of mercury in the watershed. The transport of mercury from groundwater to surface water from mercury sources identified from information in the Oak Ridge Environmental Information System was simulated using a watershed scale model calibrated to match observed daily creek flow, total suspended solids and mercury fluxes. Mercury sources at the former Building 81-10 area, where mercury was previously retorted, were modeled using a telescopic refined mesh with boundary conditions extracted from the watershed model. Modeling on a watershed scale indicated that only source excavation for soils/sediment in the vicinity of UEFPC had any effect on mercury flux in surface water. The simulations showed that colloidal transport contributed 85 percent of the total mercury flux leaving the UEFPC watershed under high flow conditions. Simulation of dissolved mercury transport from liquid elemental mercury and adsorbed sources in soil at former Building 81-10 indicated that dissolved concentrations are orders of magnitude

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

    Energy Technology Data Exchange (ETDEWEB)

    Bostick, Kent; Daniel, Anamary [Professional Project Services, Inc., Bethel Valley Road, Oak Ridge, TN, 37922 (United States); Tachiev, Georgio [Florida International University, Applied Research Center 10555 W. Flagler St., EC 2100 Miami Florida 33174 (United States); Malek-Mohammadi, Siamak [Bradley University, 413A Jobst Hall, Preoria, IL 61625 (United States)

    2013-07-01

    In this case study, groundwater/surface water modeling was used to determine efficacy of stabilization in place with hydrologic isolation for remediation of mercury contaminated areas in the Upper East Fork Poplar Creek (UEFPC) Watershed in Oak Ridge, TN. The modeling simulates the potential for mercury in soil to contaminate groundwater above industrial use risk standards and to contribute to surface water contamination. The modeling approach is unique in that it couples watershed hydrology with the total mercury transport and provides a tool for analysis of changes in mercury load related to daily precipitation, evaporation, and runoff from storms. The model also allows for simulation of colloidal transport of total mercury in surface water. Previous models for the watershed only simulated average yearly conditions and dissolved concentrations that are not sufficient for predicting mercury flux under variable flow conditions that control colloidal transport of mercury in the watershed. The transport of mercury from groundwater to surface water from mercury sources identified from information in the Oak Ridge Environmental Information System was simulated using a watershed scale model calibrated to match observed daily creek flow, total suspended solids and mercury fluxes. Mercury sources at the former Building 81-10 area, where mercury was previously retorted, were modeled using a telescopic refined mesh with boundary conditions extracted from the watershed model. Modeling on a watershed scale indicated that only source excavation for soils/sediment in the vicinity of UEFPC had any effect on mercury flux in surface water. The simulations showed that colloidal transport contributed 85 percent of the total mercury flux leaving the UEFPC watershed under high flow conditions. Simulation of dissolved mercury transport from liquid elemental mercury and adsorbed sources in soil at former Building 81-10 indicated that dissolved concentrations are orders of magnitude

  19. Mercury transformation and speciation in flue gases from anthropogenic emission sources: a critical review

    Science.gov (United States)

    Zhang, Lei; Wang, Shuxiao; Wu, Qingru; Wang, Fengyang; Lin, Che-Jen; Zhang, Leiming; Hui, Mulin; Yang, Mei; Su, Haitao; Hao, Jiming

    2016-02-01

    Mercury transformation mechanisms and speciation profiles are reviewed for mercury formed in and released from flue gases of coal-fired boilers, non-ferrous metal smelters, cement plants, iron and steel plants, waste incinerators, biomass burning and so on. Mercury in coal, ores, and other raw materials is released to flue gases in the form of Hg0 during combustion or smelting in boilers, kilns or furnaces. Decreasing temperature from over 800 °C to below 300 °C in flue gases leaving boilers, kilns or furnaces promotes homogeneous and heterogeneous oxidation of Hg0 to gaseous divalent mercury (Hg2+), with a portion of Hg2+ adsorbed onto fly ash to form particulate-bound mercury (Hgp). Halogen is the primary oxidizer for Hg0 in flue gases, and active components (e.g., TiO2, Fe2O3, etc.) on fly ash promote heterogeneous oxidation and adsorption processes. In addition to mercury removal, mercury transformation also occurs when passing through air pollution control devices (APCDs), affecting the mercury speciation in flue gases. In coal-fired power plants, selective catalytic reduction (SCR) system promotes mercury oxidation by 34-85 %, electrostatic precipitator (ESP) and fabric filter (FF) remove over 99 % of Hgp, and wet flue gas desulfurization system (WFGD) captures 60-95 % of Hg2+. In non-ferrous metal smelters, most Hg0 is converted to Hg2+ and removed in acid plants (APs). For cement clinker production, mercury cycling and operational conditions promote heterogeneous mercury oxidation and adsorption. The mercury speciation profiles in flue gases emitted to the atmosphere are determined by transformation mechanisms and mercury removal efficiencies by various APCDs. For all the sectors reviewed in this study, Hgp accounts for less than 5 % in flue gases. In China, mercury emission has a higher Hg0 fraction (66-82 % of total mercury) in flue gases from coal combustion, in contrast to a greater Hg2+ fraction (29-90 %) from non-ferrous metal smelting, cement and

  20. Mercúrio total em músculo de cação Prionace glauca (Linnaeus, 1758 e de espadarte Xiphias gladius Linnaeus, 1758, na costa sul-sudeste do Brasil e suas implicações para a saúde pública Total mercury in muscle of the shark Prionace glauca (Linnaeus, 1758 and swordfish Xiphias gladius Linnaeus, 1758, from the South-Southeast coast of Brazil and the implications for public health

    Directory of Open Access Journals (Sweden)

    Adriana C. L. Dias

    2008-09-01

    Full Text Available Foram analisadas as concentrações de mercúrio total (THg em tecido muscular do tubarão azul Prionace glauca e do teleósteo Xiphias gladius, vulgarmente conhecido como espadarte, provenientes das regiões sul e sudeste da costa brasileira, para verificar se estas se encontram dentro dos padrões legais para consumo humano. As amostras foram obtidas utilizando-se o programa REVIZEE, de agosto a setembro de 2001, e por intermédio de uma empresa de pesca em Itajaí, Santa Catarina. Foi analisado um total de 95 espécimes, testando-se as correlações entre THg, comprimento (cm e peso (kg. As concentrações de mercúrio total em todas as amostras variaram de 0,13 a 2,26µgg-1 (peso úmido. A média de mercúrio total em P. glauca foi de 0,76 ± 0,48µgg-1 (p.u., e em X. gladius foi de 0,62 ± 0,31µgg-1 (p.u. com diferença não significativa (teste Mann-Whitney, p Total mercury (THg was analyzed in muscle tissue from the blue shark Prionace glauca and the swordfish Xiphias gladius, obtained from the South and Southeast coast of Brazil, to verify compliance with current limits for human consumption. Samples were obtained through the REVIZEE Program and a commercial fishery in Itajaí, Santa Catarina State. A total of 95 specimens were analyzed (48 X. gladius and 47 P. glauca, and correlations were checked between THg and fish length and weight. THg ranged from 0.13 to 2.26µgg-1 (fresh weight, and there was no significant difference between the means for P. glauca, 0.76 ± 0.48µgg-1 (f.w. and X. gladius, 0.62 ± 0.31 (Mann-Whitney test, p < 0.05. In 16% of samples, THg was above the limits set by the National Health Surveillance Agency (ANVISA, namely 1µgg-1, and 62% exceeded the World Health Organization (WHO limit of 0.5µgg-1. The ingestion of 100g/ day-1 of P. glauca or X. gladius would result in a daily THg intake of more than twice the WHO (1990 suggested limit.

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

    International Nuclear Information System (INIS)

    Looney, B.B.

    2000-01-01

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

  2. Mercury content in Hot Springs

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, R

    1974-01-01

    A method of determination of mercury in hot spring waters by flameless atomic absorption spectrophotometry is described. Further, the mercury content and the chemical behavior of the elementary mercury in hot springs are described. Sulfide and iodide ions interfered with the determination of mercury by the reduction-vapor phase technique. These interferences could, however, be minimized by the addition of potassium permanganate. Waters collected from 55 hot springs were found to contain up to 26.0 ppb mercury. High concentrations of mercury have been found in waters from Shimoburo Springs, Aomori (10.0 ppb), Osorezan Springs, Aomori (1.3 approximately 18.8 ppb), Gosyogake Springs, Akita (26.0 ppb), Manza Springs, Gunma (0.30 approximately 19.5 ppb) and Kusatu Springs, Gunma (1.70 approximately 4.50 ppb). These hot springs were acid waters containing a relatively high quantity of chloride or sulfate.

  3. Mercury in Sediment, Water, and Biota of Sinclair Inlet, Puget Sound, Washington, 1989-2007

    Science.gov (United States)

    Paulson, Anthony J.; Keys, Morgan E.; Scholting, Kelly L.

    2010-01-01

    Historical records of mercury contamination in dated sediment cores from Sinclair Inlet are coincidental with activities at the U.S. Navy Puget Sound Naval Shipyard; peak total mercury concentrations occurred around World War II. After World War II, better metallurgical management practices and environmental regulations reduced mercury contamination, but total mercury concentrations in surface sediment of Sinclair Inlet have decreased slowly because of the low rate of sedimentation relative to the vertical mixing within sediment. The slopes of linear regressions between the total mercury and total organic carbon concentrations of sediment offshore of Puget Sound urban areas was the best indicator of general mercury contamination above pre-industrial levels. Prior to the 2000-01 remediation, this indicator placed Sinclair Inlet in the tier of estuaries with the highest level of mercury contamination, along with Bellingham Bay in northern Puget Sound and Elliott Bay near Seattle. This indicator also suggests that the 2000/2001 remediation dredging had significant positive effect on Sinclair Inlet as a whole. In 2007, about 80 percent of the area of the Bremerton naval complex had sediment total mercury concentrations within about 0.5 milligrams per kilogram of the Sinclair Inlet regression. Three areas adjacent to the waterfront of the Bremerton naval complex have total mercury concentrations above this range and indicate a possible terrestrial source from waterfront areas of Bremerton naval complex. Total mercury concentrations in unfiltered Sinclair Inlet marine waters are about three times higher than those of central Puget Sound, but the small numbers of samples and complex physical and geochemical processes make it difficult to interpret the geographical distribution of mercury in marine waters from Sinclair Inlet. Total mercury concentrations in various biota species were compared among geographical locations and included data of composite samples, individual

  4. Mercury hair levels and factors that influence exposure for residents of Huancavelica, Peru

    Science.gov (United States)

    Between 1564 and 1810, nearly 17,000 metric tons of mercury (Hg) vapor were released to the environment during cinnabar refining in the small town of Huancavelica, Peru. The present study characterizes individual exposure to mercury using total and speciated Hg from residential s...

  5. Mercury in plants and soils of the French-speaking part of Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Quinche, J P; Dvorak, V

    1975-01-01

    Samples of plants and soils from an agricultural (Changins/Nyon), industrial (Monthey) and urban (Le Vallon/Lausanne) area as well as samples from regions remote from the sources of atmospheric pollution have been analyzed for mercury. A contamination by the mercury of samples from the Monthey area could be ascertained. However, the average mercury content of 37 samples of leaves of trees and shrubs collected during fall 1974 in the Monthey area was lower by 53.2% as compared to the average value obtained in 1973;, this fact can be explained by the improved anti-pollution action taken by the chemical industry. No methyl mercury was found in the few samples from Monthey area analyzed for methyl mercury (4 samples of vegetables and one sample of tobacco leaves). On the other hand, all mushrooms, were they gathered in an area close or remote from the sources of mercury pollution, contained traces of methyl mercury (ranging between 1.9 and 28% of the total mercury content). Likewise, 4 samples of lichens gathered in Arolla (Valais) and La Fretaz/Bullet (Jura vaudois), both being remote mountain regions, did contain traces of methyl mercury (between 4.8 and 6.5% of total mercury content). Soils from Changins into which every other year, since 11 years, wheat treated with organomercury fungicides was sown, did not contain more mercury than soil from forests or mountain meadows. Samples of foliage of trees and shrubs from the vicinity of the municipal garbage combustion plant at Vallon (Lausanne) were clearly polluted by mercury. 18 references, 9 tables.

  6. Interior Volatile Reservoirs in Mercury

    Science.gov (United States)

    Anzures, B. A.; Parman, S. W.; Milliken, R. E.; Head, J. W.

    2018-05-01

    More measurements of 1) surface volatiles, and 2) pyroclastic deposits paired with experimental volatile analyses in silicate minerals can constrain conditions of melting and subsequent eruption on Mercury.

  7. Mercury in bryophytes (moss)

    Energy Technology Data Exchange (ETDEWEB)

    Yeaple, D S

    1972-01-28

    Recent reports in the literature, concerning the ability of certain mosses and lichens to concentrate heavy metals, have led to an investigation of the potential application of mosses as indicators of the transport of mercury through the atmosphere. A number of moss samples were collected to provide information regarding the level of mercury in moss around several types of populated areas. The results reported are from moss collected within an 80 mile radius of Boston, Massachusetts, along the Maine coast, near the tops of Mount Katahdin in Maine and Mount Washington in New Hampshire, and from Walden, New York, a small town located about 60 miles north of New York City. The data are admittedly limited, but provide sufficient insight into the usefulness of moss as an indicator to warrant the pursuit of a more detailed investigation. 6 references, 1 table.

  8. Integrated criteria document mercury

    International Nuclear Information System (INIS)

    Sloof, W.; Beelan, P. van; Annema, J.A.; Janus, J.A.

    1995-01-01

    The document contains a systematic review and a critical evaluation of the most relevant data on the priority substance mercury for the purpose of effect-oriented environmental policy. Chapter headings are: properties and existing standards; production, application, sources and emissions (natural sources, industry, energy, households, agriculture, dental use, waste); distribution and transformation (cinnabar; Hg 2+ , Hg 2 2+ , elemental mercury, methylmercury, behavior in soil, water, air, biota); concentrations and fluxes in the environment and exposure levels (sampling and measuring methods, occurrence in soil, water, air etc.); effects (toxicity to humans and aquatic and terrestrial systems); emissions reduction (from industrial sources, energy, waste processing etc.); and evaluation (risks, standards, emission reduction objectives, measuring strategies). 395 refs

  9. Assessment of mercury exposure among small-scale gold miners using mercury stable isotopes

    International Nuclear Information System (INIS)

    Sherman, Laura S.; Blum, Joel D.; Basu, Niladri; Rajaee, Mozhgon; Evers, David C.; Buck, David G.; Petrlik, Jindrich; DiGangi, Joseph

    2015-01-01

    Total mercury (Hg) concentrations in hair and urine are often used as biomarkers of exposure to fish-derived methylmercury (MeHg) and gaseous elemental Hg, respectively. We used Hg stable isotopes to assess the validity of these biomarkers among small-scale gold mining populations in Ghana and Indonesia. Urine from Ghanaian miners displayed similar Δ 199 Hg values to Hg derived from ore deposits (mean urine Δ 199 Hg=0.01‰, n=6). This suggests that urine total Hg concentrations accurately reflect exposure to inorganic Hg among this population. Hair samples from Ghanaian miners displayed low positive Δ 199 Hg values (0.23–0.55‰, n=6) and low percentages of total Hg as MeHg (7.6–29%, n=7). These data suggest that the majority of the Hg in these miners' hair samples is exogenously adsorbed inorganic Hg and not fish-derived MeHg. Hair samples from Indonesian gold miners who eat fish daily displayed a wider range of positive Δ 199 Hg values (0.21–1.32‰, n=5) and percentages of total Hg as MeHg (32–72%, n=4). This suggests that total Hg in the hair samples from Indonesian gold miners is likely a mixture of ingested fish MeHg and exogenously adsorbed inorganic Hg. Based on data from both populations, we suggest that total Hg concentrations in hair samples from small-scale gold miners likely overestimate exposure to MeHg from fish consumption. - Highlights: • Mercury isotopes were measured in hair and urine from small-scale gold miners. • Mercury isotopes indicate that Hg in urine comes from mining activity. • Mercury isotopes suggest Hg in hair is a mixture of fish MeHg and inorganic Hg. • A large percentage of Hg in miner’s hair is released during amalgam burning and adsorbed

  10. Impact of the Sainte-Marguerite 3 hydroelectric reservoir on the mercury exposure of local fish consumers

    International Nuclear Information System (INIS)

    Schetagne, R.; Plante, M.; Castonguay, D.

    2010-01-01

    This study examined fish mercury levels in a freshwater impoundment flooded as part of the Sainte-Marguerite-3 hydroelectric generating station. The study compared mercury levels obtained before the area was flooded in 1997 with mercury exposure surveys obtained in 2006. Mercury levels in the fish have increased by factors ranging from 4 to 8. Total mercury concentrations have reached 0.78 μg per g in 400-mm lake whitefish and 1.85 μg per g in 700-mm northern pike. Non-native fishers consumed significantly more local fish on a monthly basis after the area was flooded. Native Innu fishers consumed less fish. Average hair mercury concentrations for non-native fish consumers remained unchanged, which mercury levels in native fish consumers decreased significantly.

  11. Mercury in fish from two Nicaraguan lakes: A recommendation for increased monitoring of fish for international commerce

    International Nuclear Information System (INIS)

    McCrary, Jeffrey K.; Castro, Mark; McKaye, Kenneth R.

    2006-01-01

    We measured total mercury concentrations in water and fish of Lake Managua and Lake Apoyo. Water mercury concentrations were 10-fold higher in Lake Managua than in Lake Apoyo, although differences in mercury concentration in the most common native fish were not significant. One-fourth of the commercially fished tilapia in Lake Managua exceeded maximum recommended mercury levels for consumption among pregnant women and other at-risk groups, although bioavailability to fishes was lower than in previously studied sites in Brazil and Western Maryland. The lower bioavailiability may present important information for management options to reduce mercury exposure to fishes and humans. We recommend closer mercury monitoring among freshwater fish destined for international commerce. - Fish commonly exported into the international food supply may be contaminated with mercury

  12. Mercury in fish from two Nicaraguan lakes: A recommendation for increased monitoring of fish for international commerce

    Energy Technology Data Exchange (ETDEWEB)

    McCrary, Jeffrey K. [University of Central America, Apdo. 69, Managua (Nicaragua) and College of Natural Resources, Virginia Tech, Blacksburg, VA 24061 (United States)]. E-mail: jmccrary2@yahoo.com; Castro, Mark [Appalachian Laboratory, University of Maryland Center for Environmental Science, 301 Braddock Road, Frostburg, MD 21532 (United States); McKaye, Kenneth R. [University of Central America, Apdo. 69, Managua (Nicaragua); Appalachian Laboratory, University of Maryland Center for Environmental Science, 301 Braddock Road, Frostburg, MD 21532 (United States)

    2006-06-15

    We measured total mercury concentrations in water and fish of Lake Managua and Lake Apoyo. Water mercury concentrations were 10-fold higher in Lake Managua than in Lake Apoyo, although differences in mercury concentration in the most common native fish were not significant. One-fourth of the commercially fished tilapia in Lake Managua exceeded maximum recommended mercury levels for consumption among pregnant women and other at-risk groups, although bioavailability to fishes was lower than in previously studied sites in Brazil and Western Maryland. The lower bioavailiability may present important information for management options to reduce mercury exposure to fishes and humans. We recommend closer mercury monitoring among freshwater fish destined for international commerce. - Fish commonly exported into the international food supply may be contaminated with mercury.

  13. From Midges to Spiders: Mercury Biotransport in Riparian Zones Near the Buffalo River Area of Concern (AOC), USA.

    Science.gov (United States)

    Pennuto, C M; Smith, M

    2015-12-01

    Riparian communities can receive environmental contaminants from adjacent aquatic 'donor' habitats. We investigated mercury biotransport from aquatic to terrestrial habitats via aquatic insect emergence and uptake by riparian spiders at sites within and upstream of the Buffalo River Area of Concern (AOC), a site with known sediment Hg contamination. Mercury concentration in emerging midges was roughly 10× less than contaminated sediment levels with the AOC, but biomagnification factors from midges to spiders ranged from 2.0 to 2.65 between sites. There was a significantly negative body mass:total mercury relationship in spiders (p Spiders contained significantly more mercury than their midge prey and spiders upstream of the AOC had higher mercury concentrations than spiders from within the AOC. Collectively, these data indicate that riparian spiders can be good mercury sentinels in urban environments, and that riparian communities upstream from the AOC may be at greater risk to mercury than has been previously considered.

  14. Method for mercury refinement

    Science.gov (United States)

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

    1991-04-09

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

  15. Apparatus for mercury refinement

    Science.gov (United States)

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

    1991-07-16

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

  16. The planet Mercury (1971)

    Science.gov (United States)

    1972-01-01

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

  17. Magnetic field of Mercury

    International Nuclear Information System (INIS)

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

    1977-01-01

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

  18. Method for scavenging mercury

    Science.gov (United States)

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

    2009-01-20

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

  19. Apparatus for mercury refinement

    International Nuclear Information System (INIS)

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

    1991-01-01

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

  20. Method for mercury refinement

    International Nuclear Information System (INIS)

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

    1991-01-01

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

  1. Water striders (family Gerridae): mercury sentinels in small freshwater ecosystems

    International Nuclear Information System (INIS)

    Jardine, Timothy D.; Al, Tom A.; MacQuarrie, Kerry T.B.; Ritchie, Charles D.; Arp, Paul A.; Maprani, Antu; Cunjak, Richard A.

    2005-01-01

    To circumvent some of the previous limitations associated with contaminant-monitoring programs, we tested the suitability of the water strider (Hemiptera: Gerridae) as a mercury sentinel by comparing total mercury concentrations in water striders and brook trout (Salvelinus fontinalis) from a variety of stream sites in New Brunswick, Canada. There was a strong association between the two variables across sites (r 2 = 0.81, P < 0.001) in systems where both atmospheric deposition and a point source (an abandoned gold mine) were likely contributing to ambient mercury levels. In a small stream draining the gold mine tailings pile, water striders had mercury concentrations an order of magnitude higher than those from reference locations. Temporal variation at three southern New Brunswick stream sites was non-significant. These results suggest that water strider mercury levels accurately quantify food chain entry of the element. The use of sentinel species holds great potential for expanding contaminant-monitoring programs. - Water striders accurately reflect the entry of mercury in food chains of small freshwater systems

  2. Bioaccumulation Pattern of Mercury in Bacopa monnieri (L. Pennell

    Directory of Open Access Journals (Sweden)

    Hussain K

    2012-05-01

    Full Text Available Bioaccumulation pattern of mercury was studied in Bacopa monnieri plants cultivated in Hoagland nutrient medium artificially contaminated with 5 and 10μM HgCl2. Mercury content of roots, stem and leaves were analysed using Atomic Absorption Spectrophotometry (AAS. During a period 12 days of growth, more accumulation was noticed in roots followed by stem and leaves. Repeated addition of HgCl2 and enhanced growth period up to 50 days showed only negligible increase in accumulation maintaining a threshold level of mercury in the root. When a comparison was done between the quantities of HgCl2 added to the growth medium and the sum of total accumulation of the plant and content present in the residual medium, a significant quantity of mercury is found to be lost presumably through the process of phytovolatilization from the plant. Studies on the effect of pH on bioaccumulation of mercury showed that acidic pH enhanced accumulation rate and hence for phytoremediation technology ‘chlorination’ is recommended whereas for medicinal purpose, Bacopa monnieri plants can be harvested after ‘liming’ to increase the pH and thereby reducing accumulation rate of mercury.

  3. Influence of environmental factors on mercury release in hydroelectric reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, K.; Therien, N.

    1991-04-01

    Due to increased mercury concentrations in fish in hydro-electric reservoirs after flooding, a study was carried out to evaluate the release and transformation of mercury due to vegetation and soil flooded as a result of reservoir creation. Samples of vegetation and soils were immersed in water and concentrations of total mercury, methylmercury and nutrients were followed. The effects of anoxia, pH and temperature on release and transformation were examined. An existing dynamic model of decomposition of flooded materials in reservoirs was modified to include mercury release and transformation, and was calibrated to the experimental data. Amounts of mercury released by the different substrates was of the same order of magnitude. Tree species contributed to the greatest amounts of methylmercury per unit biomass, but the biomass used for these was twigs and foliage. Soil released significant amounts of mercury, but methylation was very low. The model was able to fit well for all substrates except lichen. The model can be adapted to proposed reservoirs to predict nutrient and mecury release and transformation. 175 refs., 38 figs., 38 tabs.

  4. Mercury distribution characteristics in primary manganese smelting plants.

    Science.gov (United States)

    Back, Seung-Ki; Sung, Jin-Ho; Moon, Young-Hoon; Kim, Young-Hee; Seok, Kwang-Seol; Song, Geum-Ju; Seo, Yong-Chil

    2017-08-01

    The mercury (Hg) distribution characteristics were investigated in three primary manganese smelting plants in Korea for the assessment of anthropogenic Hg released. Input and output materials were sampled from each process, and Hg concentrations in the samples were analyzed. Among the input materials, the most mercury was found in the manganese ore (83.1-99.7%) and mercury was mainly released through fly ash or off gas, depending on the condition of off gas cleaning system. As off gas temperature decreases, proportion and concentration of emitted gaseous elemental mercury (Hg 0 ) in off gas decreases. Based on mass balance study from these three plants and national manganese production data, the total amount of mercury released from those Korean plants was estimated to 644 kg/yr. About half of it was emitted into the air while the rest was released to waste as fly ash. With the results of this investigation, national inventory for Hg emission and release could be updated for the response to Minamata Convention on Mercury. Copyright © 2017. Published by Elsevier Ltd.

  5. Mercury mass measurement in fluorescent lamps via neutron activation analysis

    Science.gov (United States)

    Viererbl, L.; Vinš, M.; Lahodová, Z.; Fuksa, A.; Kučera, J.; Koleška, M.; Voljanskij, A.

    2015-11-01

    Mercury is an essential component of fluorescent lamps. Not all fluorescent lamps are recycled, resulting in contamination of the environment with toxic mercury, making measurement of the mercury mass used in fluorescent lamps important. Mercury mass measurement of lamps via instrumental neutron activation analysis (NAA) was tested under various conditions in the LVR-15 research reactor. Fluorescent lamps were irradiated in different positions in vertical irradiation channels and a horizontal channel in neutron fields with total fluence rates from 3×108 cm-2 s-1 to 1014 cm-2 s-1. The 202Hg(n,γ)203Hg nuclear reaction was used for mercury mass evaluation. Activities of 203Hg and others induced radionuclides were measured via gamma spectrometry with an HPGe detector at various times after irradiation. Standards containing an Hg2Cl2 compound were used to determine mercury mass. Problems arise from the presence of elements with a large effective cross section in luminescent material (europium, antimony and gadolinium) and glass (boron). The paper describes optimization of the NAA procedure in the LVR-15 research reactor with particular attention to influence of neutron self-absorption in fluorescent lamps.

  6. Database for content of mercury in Polish brown coal

    Science.gov (United States)

    Jastrząb, Krzysztof

    2018-01-01

    Poland is rated among the countries with largest level of mercury emission in Europe. According to information provided by the National Centre for Balancing and Management of Emissions (KOBiZE) more than 10.5 tons of mercury and its compounds were emitted into the atmosphere in 2015 from the area of Poland. Within the scope of the BazaHg project lasting from 2014 to 2015 and co-financed from the National Centre of Research and Development (NCBiR) a database was set up with specification of mercury content in Polish hard steam coal, coking coal and brown coal (lignite) grades. With regard to domestic brown coal the database comprises information on coal grades from Brown Coal Mines of `Bełchatów', `Adamów', `Turów' and `Sieniawa'. Currently the database contains 130 records with parameters of brown coal, where each record stands for technical analysis (content of moisture, ash and volatile particles), elemental analysis (CHNS), content of chlorine and mercury as well as net calorific value and combustion heat. Content of mercury in samples of brown coal grades under test ranged from 44 to 985 μg of Hg/kg with the average level of 345 μg of Hg/kg. The established database makes up a reliable and trustworthy source of information about content of mercury in Polish fossils. The foregoing details completed with information about consumption of coal by individual electric power stations and multiplied by appropriate emission coefficients may serve as the background to establish loads of mercury emitted into atmosphere from individual stations and by the entire sector of power engineering in total. It will also enable Polish central organizations and individual business entities to implement reasonable policy with respect of mercury emission into atmosphere.

  7. Mercury's Densely Cratered Surface

    Science.gov (United States)

    1974-01-01

    Mariner 10 took this picture (FDS 27465) of the densely cratered surface of Mercury when the spacecraft was 18,200 kilometers (8085 miles) from the planet on March 29. The dark line across top of picture is a 'dropout' of a few TV lines of data. At lower left, a portion of a 61 kilometer (38 mile) crater shows a flow front extending across the crater floor and filling more than half of the crater. The smaller, fresh crater at center is about 25 kilometers (15 miles) in diameter. Craters as small as one kilometer (about one-half mile) across are visible in the picture.The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.Image Credit: NASA/JPL/Northwestern University

  8. Mercury removal sorbents

    Science.gov (United States)

    Alptekin, Gokhan

    2016-03-29

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

  9. Mercury in Pelecanus occidentalis of the Cispata bay, Colombia

    Directory of Open Access Journals (Sweden)

    Saudith Burgos N.

    2014-06-01

    Full Text Available Objective. Assessment the total concentration of mercury in the liver and feathers of Pelecanus occidentalis of the Cispata bay, Colombia. Materials and methods. Mercury concentrations in liver and feather of Pelecanus occidentalis residents in the Cispata bay – Colombia were evaluated by digestion with an acidic mixture of H2SO4–HNO3 and KMnO4 to eliminate organic matter. The concentration of mercury was determined by the Atomic Absorption - Cold Vapor method (CVAAS. Results. Total mercury levels found in this study were higher in feathers (0.31-9.17 mgHg/kg than in the liver (0.63–6.29 mgHg/kg, being higher than those reported in other seabirds studies. Conclusions. The high levels of total mercury in feathers and liver can be explained by the feeding habits of the organisms under study, showing the utility of feathers as a potential non-invasive tool for the monitoring of the ecosystem and thereby preventing the sacrifice of specimens.

  10. Exposure of great egret (Ardea albus) nestlings to mercury through diet in the Everglades ecosystem

    Science.gov (United States)

    Frederick, Peter C; Spalding, Marilyn G.; Sepalveda, Maria S.; Williams, Gary E.; Nico, Leo G.; Robins, Robert H.

    1999-01-01

    We estimated exposure of great egret (Ardea albus) nestlings to mercury in food in the Florida Everglades, USA, by collecting regurgitated food samples during the 1993 to 1996 breeding seasons and during 1995 measured concentrations of mercury in individual prey items from those samples. Great egret nestlings had a diet composed predominantly of fish (>95% of biomass), though the species composition of fish in the diet fluctuated considerably among years. Great egrets concentrated on the larger fish available in the marsh, especially members of the Centrarchidae. The importance of all nonnative fish fluctuated from 0 to 32% of the diet by biomass and was dominated by pike killifish (Belonesox belizanus) and cichlids (Cichlidae). Total mercury concentrations in prey fish ranged from 0.04 to 1.40 mg/kg wet weight, and we found a significant relationship between mass of individual fish and mercury concentration. We estimated the concentration of total mercury in the diet as a whole by weighting the mercury concentration in a given fish species by the proportion of that species in the diet. We estimate that total mercury concentrations in the diets ranged among years from 0.37 to 0.47 mg/kg fish (4-year mean = 0.41 mg/kg). We estimated total mercury exposure in great egret nestlings by combining these mercury concentrations with measurements of food intake rate, as measured over the course of the nestling period in both lab and field situations. We estimate that, at the 0.41 mg/kg level, nestlings would ingest 4.32 mg total mercury during an 80-day nestling period. Captive feeding studies reported elsewhere suggest that this level of exposure in the wild could be associated with reduced fledging mass, increased lethargy, decreased appetite, and, possibly, poor health and juvenile survival.

  11. Global Mercury Observatory System (GMOS): measurements of atmospheric mercury in Celestun, Yucatan, Mexico during 2012.

    Science.gov (United States)

    Velasco, Antonio; Arcega-Cabrera, Flor; Oceguera-Vargas, Ismael; Ramírez, Martha; Ortinez, Abraham; Umlauf, Gunther; Sena, Fabrizio

    2016-09-01

    Within the Global Mercury Observation System (GMOS) project, long-term continuous measurements of total gaseous mercury (TGM) were carried out by a monitoring station located at Celestun, Yucatan, Mexico, a coastal site along the Gulf of Mexico. The measurements covered the period from January 28th to October 17th, 2012. TGM data, at the Celestun site, were obtained using a high-resolution mercury vapor analyzer. TGM data show values from 0.50 to 2.82 ng/m(3) with an annual average concentration of 1.047 ± 0.271 ng/m(3). Multivariate analyses of TGM and meteorological variables suggest that TGM is correlated with the vertical air mass distribution in the atmosphere, which is influenced by diurnal variations in temperature and relative humidity. Diurnal variation is characterized by higher nighttime mercury concentrations, which might be influenced by convection currents between sea and land. The back trajectory analysis confirmed that local sources do not significantly influence TGM variations. This study shows that TGM monitoring at the Celestun site fulfills GMOS goals for a background site.

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

    Directory of Open Access Journals (Sweden)

    Belinda L. Garnham

    2016-12-01

    Full Text Available Mercury is a persistent and toxic substance that can be bio-accumulated in the food chain. Natural and anthropogenic sources contribute to the mercury emitted in the atmosphere. Eskom’s coal-fired power stations in South Africa contributed just under 93% of the total electricity produced in 2015 (Eskom 2016. Trace amounts of mercury can be found in coal, mostly combined with sulphur, and can be released into the atmosphere upon combustion. Coal-fired electricity generation plants are the highest contributors to mercury emissions in South Africa. A major factor affecting the amount of mercury emitted into the atmosphere is the type and efficiency of emission abatement equipment at a power station. Eskom employs particulate emission control technology at all its coal-fired power stations, and new power stations will also have sulphur dioxide abatement technology. A co-beneficial reduction of mercury emissions exists as a result of emission control technology. The amount of mercury emitted from each of Eskom’s coal-fired power stations is calculated, based on the amount of coal burnt and the mercury content in the coal. Emission Reduction Factors (ERF’s from two sources are taken into consideration to reflect the co-benefit received from the emission control technologies at the stations. Between 17 and 23 tons of mercury is calculated to have been emitted from Eskom’s coal-fired power stations in 2015. On completion of Eskom’s emission reduction plan, which includes fabric filter plant retrofits at two and a half stations and a flue gas desulphurisation retrofit at one power station, total mercury emissions from the fleet will potentially be reduced by 6-13% by 2026 relative to the baseline. Mercury emission reduction is perhaps currently not the most pressing air quality problem in South Africa. While the focus should then be on reducing emissions of other pollutants which have a greater impact on human health, mercury emission reduction

  13. Scavenging of gaseous mercury by acidic snow at Kuujjuarapik, Northern Quebec

    International Nuclear Information System (INIS)

    Lahoutifard, Nazafarin; Poissant, Laurier; Scott, Susannah L.

    2006-01-01

    One fate of gaseous elemental mercury (GEM) in the Arctic has been identified as gas phase oxidation by halogen-containing radicals, leading to abrupt atmospheric mercury depletion concurrent with ozone depletion. Rapid deposition of oxidized mercury leads to snow enrichment in mercury. In this report, we describe experiments that demonstrate the ability of snow to directly scavenge atmospheric mercury. The study was conducted at Kuujjuarapik, Quebec, Canada (latitude 55 o 17'N). A mercury depletion event (MDE) caused the mercury concentration in the surface snow of the coastal snowpack to double, from (9.4 ± 2.0) to (19.2 ± 1.7) ng/L. Independent of the MDE, mercury concentrations increased five-fold, from (10.0 ± 0.1) to (51.4 ± 6.0) ng/L, upon spiking the snow with 500 μM hydrogen peroxide under solar irradiation. Total organic carbon in the spiked irradiated snow samples also decreased, consistent with the formation of strongly oxidizing species. The role of the snowpack in releasing GEM to the atmosphere has been reported; these findings suggest that snow may also play a role in enhancing deposition of mercury

  14. Recovery and removal of mercury from mixed wastes. Final report, September 1994--June 1995

    International Nuclear Information System (INIS)

    Sutton, W.F.; Weyand, T.E.; Koshinski, C.J.

    1995-06-01

    In recognition of the major environmental problem created by mercury contamination of wastes and soils at an estimated 200,000 sites along US natural gas and oil pipelines and at a number of government facilities, including Oak Ridge, Savannah River, Hanford, and Rocky Flats, the US Department of Energy (DOE) is seeking an effective and economical process for removing mercury from various DOE waste streams in order to allow the base waste streams to be treated by means of conventional technologies. In response to the need for Unproved mercury decontamination technology, Mercury Recovery Services (MRS) has developed and commercialized a thermal treatment process for the recovery of mercury from contaminated soils and industrial wastes. The objectives of this program were to: demonstrate the technical and economic feasibility of the MRS process to successfully remove and recover mercury from low-level mixed waste containing mercury compounds (HgO, HgS, HgCl 2 ) and selected heavy metal compounds (PbO, CdO); determine optimum processing conditions required to consistently reduce the residual total mercury content to 1 mg/kg while rendering the treated product nontoxic as determined by TCLP methods; and provide an accurate estimate of the capital and operating costs for a commercial processing facility designed specifically to remove and recovery mercury from various waste streams of interest at DOE facilities. These objectives were achieved in a four-stage demonstration program described within with results

  15. Evaluation of zebra mussels (Dreissena polymorpha) as biomonitors of mercury contamination in aquatic ecosystems.

    Science.gov (United States)

    Blackwell, Bradley D; Driscoll, Charles T; Spada, Michael E; Todorova, Svetoslava G; Montesdeoca, Mario R

    2013-03-01

    Zebra mussels have invaded many lakes in the United States and could be a useful tool for monitoring responses of aquatic biota to changes in mercury loading. The goal of the present study was to evaluate zebra mussels for use as a biomonitor of mercury contamination by comparing zebra mussel mercury concentrations between a lake with only indirect atmospheric mercury contamination (Otisco Lake, NY, USA) and a lake that was directly contaminated by mercury discharges (Onondaga Lake, NY, USA). Zebra mussels were sampled in both the spring and fall of 2004 and 2005. Total mercury (THg) concentrations in zebra mussels were approximately seven times greater in Onondaga Lake than in Otisco Lake, and water column mercury concentrations differed by an order of magnitude between the two lakes. Seasonal differences resulted in significantly higher zebra mussel THg concentrations during the fall for both lakes. There was also significant variation among different sampling sites in Onondaga Lake. Mussel methylmercury concentrations averaged 53% of THg concentrations but were highly variable. Strong relationships between water column THg and zebra mussel THg suggest that zebra mussels are a good indicator of aquatic mercury concentrations and could be used as an effective biomonitor of mercury contamination in aquatic ecosystems. Copyright © 2013 SETAC.

  16. Mercury adsorption in the Mississippi River deltaic plain freshwater marsh soil of Louisiana Gulf coastal wetlands.

    Science.gov (United States)

    Park, Jong-Hwan; Wang, Jim J; Xiao, Ran; Pensky, Scott M; Kongchum, Manoch; DeLaune, Ronald D; Seo, Dong-Cheol

    2018-03-01

    Mercury adsorption characteristics of Mississippi River deltaic plain (MRDP) freshwater marsh soil in the Louisiana Gulf coast were evaluated under various conditions. Mercury adsorption was well described by pseudo-second order and Langmuir isotherm models with maximum adsorption capacity of 39.8 mg g -1 . Additional fitting of intraparticle model showed that mercury in the MRDP freshwater marsh soil was controlled by both external surface adsorption and intraparticle diffusion. The partition of adsorbed mercury (mg g -1 ) revealed that mercury was primarily adsorbed into organic-bond fraction (12.09) and soluble/exchangeable fraction (10.85), which accounted for 63.5% of the total adsorption, followed by manganese oxide-bound (7.50), easily mobilizable carbonate-bound (4.53), amorphous iron oxide-bound (0.55), crystalline Fe oxide-bound (0.41), and residual fraction (0.16). Mercury adsorption capacity was generally elevated along with increasing solution pH even though dominant species of mercury were non-ionic HgCl 2 , HgClOH and Hg(OH) 2  at between pH 3 and 9. In addition, increasing background NaCl concentration and the presence of humic acid decreased mercury adsorption, whereas the presence of phosphate, sulfate and nitrate enhanced mercury adsorption. Mercury adsorption in the MRDP freshwater marsh soil was reduced by the presence of Pb, Cu, Cd and Zn with Pb showing the greatest competitive adsorption. Overall the adsorption capacity of mercury in the MRDP freshwater marsh soil was found to be significantly influenced by potential environmental changes, and such factors should be considered in order to manage the risks associated with mercury in this MRDP wetland for responding to future climate change scenarios. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Rotation of the planet mercury.

    Science.gov (United States)

    Jefferys, W H

    1966-04-08

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

  18. Mercury: Exploration of a Planet

    Science.gov (United States)

    1976-01-01

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

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

    Science.gov (United States)

    2010-10-01

    ... ounces) of mercury per package; (iv) Tubes which are completely jacketed in sealed leakproof metal cases... 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...

  20. [Characteristic of Mercury Emissions and Mass Balance of the Typical Iron and Steel Industry].

    Science.gov (United States)

    Zhang, Ya-hui; Zhang, Cheng; Wang, Ding-yong; Luo, Cheng-zhong; Yang, Xi; Xu, Feng

    2015-12-01

    To preliminarily discuss the mercury emission characteristics and its mass balance in each process of the iron and steel production, a typical iron and steel enterprise was chosen to study the total mercury in all employed materials and estimate the input and output of mercury during the steel production process. The results showed that the mercury concentrations of input materials in each technology ranged 2.93-159.11 µg · kg⁻¹ with the highest level observed in ore used in blast furnace, followed by coal of sintering and blast furnace. The mercury concentrations of output materials ranged 3.09-18.13 µg · kg⁻¹ and the mercury concentration of dust was the highest, followed by converter slag. The mercury input and the output in the coking plant were 1346.74 g · d⁻¹ ± 36.95 g · d⁻¹ and 177.42 g · d⁻¹ ± 13.73 g · d⁻¹, respectively. In coking process, mercury mainly came from the burning of coking coal. The sintering process was the biggest contributor for mercury input during the iron and steel production with the mercury input of 1075. 27 g · d⁻¹ ± 60.89 g · d⁻¹ accounting for 68.06% of the total mercury input during this production process, and the ore powder was considered as the main mercury source. For the solid output material, the output in the sintering process was 14.15 g · d⁻¹ ± 0.38 g · d⁻¹, accounting for 22.61% of the total solid output. The mercury emission amount from this studied iron and steel enterprise was estimated to be 553.83 kg in 2013 with the emission factor of 0.092 g · t⁻¹ steel production. Thus, to control the mercury emissions, iron and steel enterprises should combine with production practice, further reduce energy consumption of coking and sintering, or improve the quality of raw materials and reduce the input of mercury.

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

    OpenAIRE

    Park, Jung-Duck; Zheng, Wei

    2012-01-01

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

  2. [Mercury concentration of fish in Tokyo Bay and the surrounding sea area].

    Science.gov (United States)

    Zhang, R; Kashima, Y; Matsui, M; Okabe, T; Doi, R

    2001-07-01

    Total mercury in the muscles of three fish species was analyzed in fish caught in Tokyo Bay and the surrounding sea areas, Sagami Bay and Choshi. Tokyo Bay is a semi-closed sea area surrounded by Tokyo, Kanagawa and Chiba prefectures. Sagami Bay and Choshi are open to the Pacific Ocean. A total of 412 fish consisting of northern whiting (Sillago japonica), flatfish (Limanda yokohamae) and sardine (Sardinops melanosticta) were caught in these areas over a 6 months period from November 1998 to April 1999. Total mercury concentration ranged from 0.008-0.092 microgram/g (wet wt.) in northern whiting, 0.006-0.065 microgram/g in flatfish and 0.001-0.045 microgram/g in sardine. All concentrations were below the restriction limit of fish mercury in Japan, 0.4 microgram/g of total mercury concentration. A significant correlation was found between mercury concentrations and body length or body weight in northern whiting and flatfish, irrespective of the sea area. A correlation was also found between mercury concentration in fish and their feeding habits: among the 3 species caught in the same area, crustacean feeding northern whiting had the highest, polychaete feeding flatfish moderate, and plankton feeding sardine had the lowest mercury concentration. In a comparison of mercury concentration in the same species caught in different sea areas, a higher concentration was noted in fish caught in the semi-closed sea area of Tokyo Bay, than in fish caught in the open sea areas of Sagami Bay and Choshi. This difference was most marked in fish caught at the bottom of Tokyo Bay and we considered that the mercury concentration of seawater and sediment in these areas was the cause of mercury accumulation in fish. These findings suggest that improved water quality control and environmental monitoring is necessary in semi-closed sea areas such as Tokyo Bay.

  3. Mercury in the atmosphere, snow and melt water ponds in the North Atlantic Ocean during Arctic summer.

    Science.gov (United States)

    Aspmo, Katrine; Temme, Christian; Berg, Torunn; Ferrari, Christophe; Gauchard, L Pierre-Alexis; Fain, Xavier; Wibetoe, Grethe

    2006-07-01

    Atmospheric mercury speciation measurements were performed during a 10 week Arctic summer expedition in the North Atlantic Ocean onboard the German research vessel RV Polarstern between June 15 and August 29, 2004. This expedition covered large areas of the North Atlantic and Arctic Oceans between latitudes 54 degrees N and 85 degrees N and longitudes 16 degrees W and 16 degrees E. Gaseous elemental mercury (GEM), reactive gaseous mercury (RGM) and mercury associated with particles (Hg-P) were measured during this study. In addition, total mercury in surface snow and meltwater ponds located on sea ice floes was measured. GEM showed a homogeneous distribution over the open North Atlantic Ocean (median 1.53 +/- 0.12 ng/m3), which is in contrast to the higher concentrations of GEM observed over sea ice (median 1.82 +/- 0.24 ng/m3). It is hypothesized that this results from either (re-) emission of mercury contained in snow and ice surfaces that was previously deposited during atmospheric mercury depletion events (AMDE) in the spring or evasion from the ocean due to increased reduction potential at high latitudes during Arctic summer. Measured concentrations of total mercury in surface snow and meltwater ponds were low (all samples RGM and Hg-P without a significant diurnal variability. These results indicate that the production and deposition of these reactive mercury species do not significantly contribute to the atmospheric mercury cycle in the North Atlantic Ocean during the Arctic summer.

  4. Lifespan mercury accumulation pattern in Liza aurata : Evidence from two southern European estuaries

    Science.gov (United States)

    Tavares, S.; Oliveira, H.; Coelho, J. P.; Pereira, M. E.; Duarte, A. C.; Pardal, M. A.

    2011-10-01

    Mercury accumulation throughout the lifespan of Liza aurata (Risso, 1810) was analysed in four tissues (muscle, gills, liver and brain) in two southern European coastal ecosystems with distinct mercury contamination. Specimens from four to five age classes were captured in two sampling sites in the Ria de Aveiro (Laranjo bay and Mira), a system historically contaminated by industrial mercury, and in one site in the Mondego estuary, assumed as a mercury-free ecosystem. Mercury concentration in all tissues was found to be significantly higher in the Ria de Aveiro (Laranjo bay) compared to the Mondego, in accordance with the environmental contamination (water, sediments and suspended particulate matter). Significant differences inside the Ria de Aveiro (between the Mira and Laranjo bay) were only detected in the liver. This tissue registered the highest levels of mercury (ranging from 0.11 to 4.2 μg g -1 ) in all sampling sites, followed by muscle, brain, and gills. In all sampling sites and tissues was denoted a mercury dilution pattern along the lifecycle (except in liver at the Mondego, the reference area where the concentrations are always very low). An exponential trend was found in the metal age variation patterns in Laranjo (the most contaminated area) and a linear trend in the Mira and the Mondego (the least contaminated areas). Organic mercury concentration in muscle generally accounted for over 95% of total mercury concentration, and followed the same accumulation pattern of total mercury. This fish species is of lesser importance in mercury transfer to adjacent coastal areas and although the consumption of fish from Laranjo may present some risk for the humans, this risk decreases with fish age/size.

  5. EVALUATION OF MERCURY EMISSIONS FROM COAL-FIRED FACILITIES WITH SCR AND FGD SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    J.A. Withum; S.C. Tseng; J.E. Locke

    2005-11-01

    -to-stack basis, was 53%. The average Hg concentration in the stack flue gas was 4.09 {micro}g/m{sup 3}. The average stack mercury emission was 3.47 Ib/TBtu. The mercury material balance closures ranged from 87% to 108%, with an average of 97%. A sampling program similar to this one was performed on a similar unit (at the same plant) that was equipped with an SCR for NOx control. Comparison of the results from the two units show that the SCR increases the percentage of mercury that is in the oxidized form, which, in turn, lends to more of the total mercury being removed in the wet scrubber. The principal purpose of this work is to develop a better understanding of the potential mercury removal ''co-benefits'' achieved by NOx, and SO{sub 2} control technologies. It is expected that this data will provide the basis for fundamental scientific insights into the nature of mercury chemistry in flue gas, the catalytic effect of SCR systems on mercury speciation and the efficacy of different FGD technologies for mercury capture. Ultimately, this insight could help to design and operate SCR and FGD systems to maximize mercury removal.

  6. Methods for dispensing mercury into devices

    Science.gov (United States)

    Grossman, Mark W.; George, William A.

    1987-04-28

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

  7. Determination of mercury in plant material

    Energy Technology Data Exchange (ETDEWEB)

    Pickard, J A; Martin, J T

    1960-07-01

    An analytical procedure used for the determination of traces of mercury in plant material is described. The conditions of combustion of organic matter are controlled to avoid loss of mercury and EDTA is used to reduce the values for apparent mercury on uncontaminated samples. Satisfactory recoveries of mercury added to apples, tomatoes and coffee are obtained. 10 references, 1 table.

  8. Ultrasound-assisted vapor generation of mercury

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Anderson S.; Vieira, Mariana A. [Universidade Federal de Santa Catarina, Departamento de Quimica, Florianopolis, SC (Brazil); Willie, Scott; Sturgeon, Ralph E. [National Research Council Canada, Institute for National Measurement Standards, Ottawa, ON (Canada)

    2007-06-15

    Cold vapor generation arising from reduction of both Hg{sup 2+} and CH{sub 3}Hg{sup +} occurs using ultrasonic (US) fields of sufficient density to achieve both localized heating as well as radical-based attack in solutions of formic and acetic acids and tetramethylammonium hydroxide (TMAH). A batch sonoreactor utilizing an ultrasonic probe as an energy source and a flow through system based on a US bath were optimized for this purpose. Reduction of CH{sub 3}Hg{sup +} to Hg{sup 0} occurs only at relatively high US field density (>10 W cm{sup -3} of sample solution) and is thus not observed when a conventional US bath is used for cold vapor generation. Speciation of mercury is thus possible by altering the power density during the measurement process. Thermal reduction of Hg{sup 2+} is efficient in formic acid and TMAH at 70 C and occurs in the absence of the US field. Room temperature studies with the batch sonoreactor reveal a slow reduction process, producing temporally broad signals having an efficiency of approximately 68% of that arising from use of a conventional SnCl{sub 2} reduction system. Molecular species of mercury are generated at high concentrations of formic and acetic acid. Factors affecting the generation of Hg{sup 0} were optimized and the batch sonoreactor used for the determination of total mercury in SLRS-4 river water reference material. (orig.)

  9. Ultrasound-assisted vapor generation of mercury.

    Science.gov (United States)

    Ribeiro, Anderson S; Vieira, Mariana A; Willie, Scott; Sturgeon, Ralph E

    2007-06-01

    Cold vapor generation arising from reduction of both Hg(2+) and CH(3)Hg(+) occurs using ultrasonic (US) fields of sufficient density to achieve both localized heating as well as radical-based attack in solutions of formic and acetic acids and tetramethylammonium hydroxide (TMAH). A batch sonoreactor utilizing an ultrasonic probe as an energy source and a flow through system based on a US bath were optimized for this purpose. Reduction of CH(3)Hg(+) to Hg(0) occurs only at relatively high US field density (>10 W cm(-3) of sample solution) and is thus not observed when a conventional US bath is used for cold vapor generation. Speciation of mercury is thus possible by altering the power density during the measurement process. Thermal reduction of Hg(2+) is efficient in formic acid and TMAH at 70 degrees C and occurs in the absence of the US field. Room temperature studies with the batch sonoreactor reveal a slow reduction process, producing temporally broad signals having an efficiency of approximately 68% of that arising from use of a conventional SnCl(2) reduction system. Molecular species of mercury are generated at high concentrations of formic and acetic acid. Factors affecting the generation of Hg(0) were optimized and the batch sonoreactor used for the determination of total mercury in SLRS-4 river water reference material.

  10. Determination of mercury and selenium in hair samples of Brazilian Indian populations living in the Amazonic region by NAA

    International Nuclear Information System (INIS)

    Vasconcellos, M.B.A.; Paletti, G.; Catharino, M.G.M.; Saiki, M.; Favaro, D.I.T.; Bode, P.; Ammerlaan, A.K.; Byrne, A.R.; Baruzzi, R.; Rodrigues, D.A.

    2000-01-01

    Biomonitoring of mercury contamination of Brazilian Indian population groups living in the Xingu Park, a reservation situated in the Amazonic region, has revealed very high levels of mercury in hair samples as compared to controls. Total mercury was determined by INAA in most of the tribes living in the Park and methylmercury was determined by CVAAS in samples with total mercury above 10 mg/kg. Due to the fact that selenium seems to protect animals against the toxic effects of methylmercury, it was considered also of interest to determine its concentrations in the hair samples with very high mercury levels. Selenium was determined by INAA via the short-lived radionuclide 77m Se (T 1/2 = 17.45 s). The correlations between selenium and mercury concentrations in Brazilian controls and in the Indian population groups are discussed. (author)

  11. Levels of Mercury in Persian Gulf Frozen Fish Species

    Directory of Open Access Journals (Sweden)

    Parisa Ziarati

    2017-03-01

    Full Text Available Severe discharge of sewage and industrial effluents into the Persian Gulf leads to the deposition of various types of heavy metals, especially lead and mercury, in the muscles of fish. Total mercury and methylmercury contents were determined in the edible parts (muscle tissue, fillet of two different most popular frozen fish species from the Persian Gulf to ascertain whether the concentrations exceeded the maximum level fixed by the European Commission or not. During the period from October 2015 to June 2016, a total of 150 frozen fish packaged samples were randomly collected from the recognized supermarkets in Tehran province, Iran. The mercury (Hg concentration of samples was determined by atomic absorption spectrophotometer using a mercuric hydride system (MHS 10 and also by direct mercury analyzer (DMA. High concentration of total Hg was found in a Carcharhinus dussumie brand (0.91 ± 0.12 μg/g while the lowest level was detected in Pomadasys furcatus (0.29 ± 0.02 μg/g. In current study the mean concentrations of Mercury in all studied frozen fish samples were 0.79 ± 0.11 µg/g that means Hg levels were above 0.5 μg/g, which is the maximum standard level recommended by Joint FAO/WHO/Expert Committee on Food Additives (JECFA. In 13% of Pomadasys and in 47.2 % of Carcharhinus fish samples total mercury concentrations exceeded the maximum level fixed by the European Commission. All samples had also mean Hg concentrations that exceeded EPA's established safety level of 0.3 μg/g.

  12. Mercury's Lithospheric Magnetization

    Science.gov (United States)

    Johnson, C.; Phillips, R. J.; Philpott, L. C.; Al Asad, M.; Plattner, A.; Mast, S.; Kinczyk, M. J.; Prockter, L. M.

    2017-12-01

    Magnetic field data obtained by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft have been used to demonstrate the presence of lithospheric magnetization on Mercury. Larger amplitude fields resulting from the core dynamo and the strongly time-varying magnetospheric current systems are first estimated and subtracted from the magnetic field data to isolate lithospheric signals with wavelengths less than 500 km. These signals (hereafter referred to as data) are only observed at spacecraft altitudes less than 120 km, and are typically a few to 10 nT in amplitude. We present and compare equivalent source dipole magnetization models for latitudes 35°N to 75°N obtained from two distinct approaches to constrain the distribution and origin of lithospheric magnetization. First, models that fit either the data or the surface field predicted from a regional spherical harmonic representation of the data (see Plattner & Johnson abstract) and that minimize the root mean square (RMS) value of the magnetization are derived. Second, models in which the spatial distribution of magnetization required to fit the data is minimized are derived using the approach of Parker (1991). As seen previously, the largest amplitudes of lithospheric magnetization are concentrated around the Caloris basin. With this exception, across the northern hemisphere there are no overall correlations of magnetization with surface geology, although higher magnetizations are found in regions with darker surfaces. Similarly, there is no systematic correlation of magnetization signatures with crater materials, although there are specific instances of craters with interiors or ejecta that have magnetizations distinct from the surrounding region. For the latter case, we observe no correlation of the occurrence of these signatures with crater degradation state (a proxy for age). At the lowest spacecraft altitudes (source depths less than O(10 km) are unlikely in most regions

  13. Atmospheric mercury monitoring survey in Beijing, China.

    Science.gov (United States)

    Liu, Shili; Nadim, Farhad; Perkins, Chris; Carley, Robert J; Hoag, George E; Lin, Yuhan; Chen, Letian

    2002-07-01

    With the aid of one industrial, two urban, two suburban, and two rural sampling locations, diurnal patterns of total gaseous mercury (TGM) were monitored in January, February and September of 1998 in Beijing, China. Monitoring was conducted in six (two urban, two suburban, one rural and the industrial sites) of the seven sampling sites during January and February (winter) and in four (two urban, one rural, and the industrial sites) of the sampling locations during September (summer) of 1998. In the three suburban sampling stations, mean TGM concentrations during the winter sampling period were 8.6, 10.7, and 6.2 ng/m3, respectively. In the two urban sampling locations mean TGM concentrations during winter and summer sampling periods were 24.7, 8.3, 10, and 12.7 ng/m3, respectively. In the suburban-industrial and the two rural sampling locations, mean mercury concentrations ranged from 3.1-5.3 ng/m3 in winter to 4.1-7.7 ng/m3 in summer sampling periods. In the Tiananmen Square (urban), and Shijingshan (suburban) sampling locations the mean TGM concentrations during the summer sampling period were higher than winter concentrations, which may have been caused by evaporation of soil-bound mercury in warm periods. Continuous meteorological data were available at one of the suburban sites, which allowed the observation of mercury concentration variations associated with some weather parameters. It was found that there was a moderate negative correlation between the wind speed and the TGM concentration at this suburban sampling location. It was also found that during the sampling period at the same site, the quantity of TGM transported to or from the sampling site was mainly influenced by the duration and frequency of wind occurrence from certain directions.

  14. Analysis of mercury in simulated nuclear waste

    International Nuclear Information System (INIS)

    Policke, T.A.; Johnson, L.C.; Best, D.R.

    1991-01-01

    Mercury, Hg, is a non-radioactive component in the High Level Waste at the Savannah River Site (SRS). Thus, it is a component of the Defense Waste Processing Facility's (DWPF) process streams. It is present because mercuric nitrate (Hg(NO 3 ) 2 ) is used to dissolve spent fuel rods. Since mercury halides are extremely corrosive, especially at elevated temperatures such as those seen in a melter (1150 degrees C), its concentration throughout the process needs to be monitored so that it is at an acceptable level prior to reaching the melter off-gas system. The Hg can be found in condensates and sludge feeds and throughout the process and process lines, i.e., at any sampling point. The different samples types that require Hg determinations in the process streams are: (1) sludges, which may be basic or acidic and may or may not include aromatic organics, (2) slurries, which are sludges with frit and will always contain organics (formate and aromatics), and (3) condensates, from feed prep and melter off-gas locations. The condensates are aqueous and the mercury may exist as a complex mixture of halides, oxides, and metal, with levels between 10 and 100 ppm. The mercury in the sludges and slurries can be Hg 0 , Hg +1 , or Hg +2 , with levels between 200 and 3000 ppm, depending upon the location, both time and position, of sampling. For DWPF, both total and soluble Hg concentrations need to be determined. The text below describes how these determinations are being made by the Defense Waste Processing Technology (DWPT) Analytical Laboratory at the Savannah River Site. Both flame atomic absorption (FAA) and cold vapor atomic (CVAA) measurements are discussed. Also, the problems encountered in the steps toward measuring HG in these samples types of condensates and sludges are discussed along with their solutions

  15. Mercury Specie and Multi-Pollutant Control

    Energy Technology Data Exchange (ETDEWEB)

    Rob James; Virgil Joffrion; John McDermott; Steve Piche

    2010-05-31

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

  16. Radar observations of Mercury

    International Nuclear Information System (INIS)

    Harmon, J.K.; Campbell, D.B.

    1988-01-01

    Some of the radar altimetry profiles of Mercury obtained on the basis of data from the Arecibo Observatory are presented. In these measurements, the delay-Doppler method was used to measure altitudes along the Doppler equator, rather than to map radar reflectivity. The profiles, derived from observations made over a 6-yr period, provide extensive coverage over a restricted equatorial band and permit the identification of radar signatures for features as small as 50-km diameter craters and 1-km-high arcuate scarps. The data allowed identification of large-scale topographic features such as smooth plains subsidence zones and major highland regions

  17. Fluorescent sensor for mercury

    Science.gov (United States)

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

    2011-11-22

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

  18. Mercury in sediment, water, and fish in a managed tropical wetland-lake ecosystem.

    Science.gov (United States)

    Malczyk, Evan A; Branfireun, Brian A

    2015-08-15

    Mercury pollution has not been well documented in the inland lakes or fishes of Mexico, despite the importance of freshwater fish as a source of protein in local diets. Total mercury and methylmercury in waters, sediments, and the commercial fish catch were investigated in Lake Zapotlán, Mexico. Concentrations of total and methylmercury were very high in runoff and wastewater inputs, but very low in sediments and surface waters of the open water area of the lake. Concentrations of total mercury in tilapia and carp were very low, consistent with the low concentrations in lake water and sediments. Particle settling, sorption, the biogeochemical environment, and/or bloom dilution are all plausible explanations for the significant reductions in both total mercury and methylmercury. Despite very high loading of mercury, this shallow tropical lake was not a mercury-impaired ecosystem, and these findings may translate across other shallow, alkaline tropical lakes. Importantly, the ecosystem services that seemed to be provided by peripheral wetlands in reducing mercury inputs highlight the potential for wetland conservation or restoration in Mexico. Copyright © 2015. Published by Elsevier B.V.

  19. Sampling problems and the determination of mercury in surface water, seawater, and air

    International Nuclear Information System (INIS)

    Das, H.A.; van der Sloot, H.A.

    1976-01-01

    Analysis of surface water for mercury comprises the determination of both ionic and organically bound mercury in solution and that of the total mercury content of the suspended matter. Eventually, metallic mercury has to be determined too. Requirements for the sampling procedure are given. A method for the routine determination of mercury in surface water and seawater was developed and applied to Dutch surface waters. The total sample volume is 2500 ml. About 500 ml is used for the determination of the content of suspended matter and the total amount of mercury in the water. The sample is filtered through a bed of previously purified active charcoal at a low flow-rate. The main portion ca. 2000 ml) passes a flow-through centrifuge to separate the solid fraction. One liter is used to separate ''inorganic'' mercury by reduction, volatilization in an airstream and adsorption on active charcoal. The other liter is led through a column of active charcoal to collect all mercury. The procedures were checked with 197 Hg radiotracer both as an ion and incorporated in organic compounds. The mercury is determined by thermal neutron activation, followed by volatilization in a tube furnace and adsorption on a fresh carbon bed. The limit of determination is approximately equal to 1 ng 1 -1 . The rate of desorption from and adsorption on suspended material has been measured as a function of a pH of the solution for Hg +2 and various other ions. It can be concluded that only the procedure mentioned above does not disturb the equilibrium. The separation of mercury from air is obtained by suction of 1 m 3 through a 0.22 μm filter and a charcoal bed. The determination is then performed as in the case of the water samples

  20. Volcanic mercury in Pinus canariensis

    Science.gov (United States)

    Rodríguez Martín, José Antonio; Nanos, Nikos; Miranda, José Carlos; Carbonell, Gregoria; Gil, Luis

    2013-08-01

    Mercury (Hg) is a toxic element that is emitted to the atmosphere by both human activities and natural processes. Volcanic emissions are considered a natural source of mercury in the environment. In some cases, tree ring records taken close to volcanoes and their relation to volcanic activity over time are contradictory. In 1949, the Hoyo Negro volcano (La Palma-Canary Islands) produced significant pyroclastic flows that damaged the nearby stand of Pinus canariensis. Recently, 60 years after the eruption, we assessed mercury concentrations in the stem of a pine which survived volcano formation, located at a distance of 50 m from the crater. We show that Hg content in a wound caused by pyroclastic impacts (22.3 μg kg-1) is an order of magnitude higher than the Hg concentrations measured in the xylem before and after the eruption (2.3 μg kg-1). Thus, mercury emissions originating from the eruption remained only as a mark—in pyroclastic wounds—and can be considered a sporadic and very high mercury input that did not affect the overall Hg input in the xylem. In addition, mercury contents recorded in the phloem (9.5 μg kg-1) and bark (6.0 μg kg-1) suggest that mercury shifts towards non-living tissues of the pine, an aspect that can be related to detoxification in volcanism-adapted species.

  1. Atmospheric mercury footprints of nations.

    Science.gov (United States)

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

    2015-03-17

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

  2. Volcanic mercury in Pinus canariensis.

    Science.gov (United States)

    Rodríguez Martín, José Antonio; Nanos, Nikos; Miranda, José Carlos; Carbonell, Gregoria; Gil, Luis

    2013-08-01

    Mercury (Hg) is a toxic element that is emitted to the atmosphere by both human activities and natural processes. Volcanic emissions are considered a natural source of mercury in the environment. In some cases, tree ring records taken close to volcanoes and their relation to volcanic activity over time are contradictory. In 1949, the Hoyo Negro volcano (La Palma-Canary Islands) produced significant pyroclastic flows that damaged the nearby stand of Pinus canariensis. Recently, 60 years after the eruption, we assessed mercury concentrations in the stem of a pine which survived volcano formation, located at a distance of 50 m from the crater. We show that Hg content in a wound caused by pyroclastic impacts (22.3 μg kg(-1)) is an order of magnitude higher than the Hg concentrations measured in the xylem before and after the eruption (2.3 μg kg(-1)). Thus, mercury emissions originating from the eruption remained only as a mark-in pyroclastic wounds-and can be considered a sporadic and very high mercury input that did not affect the overall Hg input in the xylem. In addition, mercury contents recorded in the phloem (9.5 μg kg(-1)) and bark (6.0 μg kg(-1)) suggest that mercury shifts towards non-living tissues of the pine, an aspect that can be related to detoxification in volcanism-adapted species.

  3. Health and environmental impact of mercury in the Philippines using nuclear techniques

    International Nuclear Information System (INIS)

    Cortes-Maramba, Nelia; Reyes, J.P.; Panganiban, L.C.P.; Francisco-Rivera, Ana Trinidad; Suplido, M.L.; Akagi, Hirokatsu

    2002-01-01

    Mercury pollution in most parts of the regions in the world are caused by release into the environment of metallic mercury used in the recovery of gold by an amalgamation technique with subsequent mercury emission into the atmosphere by blowtorching operations. Significant small-scale gold mining operations in other countries such as Tanzania, Philippines, Indonesia, China and Vietnam have been reported with roughly 10 million people estimated to be involved in these activities Artisanal gold mining activities using mercury has proliferated in various parts of the country since the early 1980's. In Southern Philippines, it is estimated that a small-scale gold processor utilizes one kilogram of mercury every week or an average of fifty-two kgs/1yr. Production is estimated at 30 kilograms of gold per day. It has been estimated that 140 tons of mercury flux has been dumped directly into the river systems from small-scale gold mining operations in one of the gold rush areas in the country. In the 1980's, gold rush activities intensified in Northeastern Mindanao providing livelihood opportunities to about 80,000-120,000 people at the height of mining activities in the area. In gold mining areas it should be noted that transformation in the natural environment of inorganic mercury to methylmercury occurs which can easily bio-accumulate in fish and other organisms through the aquatic food chains. Therefore, there are two main exposure pathways of mercury contamination that can affect the human population in gold mining areas. First, gold miners and workers are exposed to inorganic mercury due to direct inhalation of mercury during gold recovery processes and second, people living along the river systems and depending on riverine products for food sources can be exposed to methylmercury mainly through fish consumption. Presently, environmental and health monitoring conducted by several government agencies in the recent past were limited to the determination of total

  4. Landfill is an important atmospheric mercury emission source

    Institute of Scientific and Technical Information of China (English)

    FENG Xinbin; TANG Shunlin; LI Zhonggen; WANG Shaofeng; LIANG Lian

    2004-01-01

    Since municipal wastes contain refuses with high mercury contents, incineration of municipal wastes becomes the major anthropogenic atmospheric mercury emission source. In China, landfills are however the main way to dispose of municipal wastes. Total gaseous mercury (TGM) concentrations in landfill gas of Gaoyan sanitary landfill located in suburb of Guiyang City were monitored using a high temporal resolved automated mercury analyzer, and mono-methylmercury (MMHg) and dimethylmercury (DMHg) concentrations in landfill gas were also measured using GC coupled with the cold vapor atomic fluorescence (CVAFS) method. Meanwhile, the TGM exchange fluxes between exposed waste and air and the soil surface of the landfill and air, were measured using low Hg blank quartz flux chamber coupled with high temporal resolved automated mercury analyzer technique. TGM concentrations in landfill gas from half year filling area averaged out at 665.52±291.25 ng/m3, which is comparable with TGM concentrations from flue gas of a small coal combustion boiler in Guiyang. The average MMHg and DMHg concentrations averaged out at 2.06±1.82 ng/m3 and 9.50±5.18 ng/m3, respectively. It is proven that mercury emission is the predominant process at the surfaces of both exposed wastes and soil of landfill. Landfills are not only TGM emission source, but also methylmercury emission source to the ambient air. There are two ways to emit mercury to the air from landfills, one is with the landfill gas through landfill gas duct, and the other through soil/air exchange. The Hg emission processes from landfills are controlled by meteorological parameters.

  5. The Content of Mercury in Herbal Dietary Supplements.

    Science.gov (United States)

    Brodziak-Dopierała, Barbara; Fischer, Agnieszka; Szczelina, Wioletta; Stojko, Jerzy

    2018-01-17

    The dietary supplement market in Poland has been growing rapidly, and the number of registered products and their consumption increases steadily. Among the most popular and the easiest to get are herbal supplements, available in any supermarket. The aim of this paper was to investigate the mercury content in the herbal supplements. The dietary supplements that have been examined (24) are available on the Polish market and contain one or more herbal ingredients. Supplements were pulverized in porcelain mortar and identified by AMA 254 atomic absorption spectrometer. The range of variations for all tested supplements was within 0.02-4293.07 μg/kg. The arithmetic mean of the total result was 193.77 μg/kg. A higher mercury content then this mean was found in preparations-bamboo shoots and alga Chlorella pyrenoidosa. The studies have shown that mercury is present in every examined herbal supplement, and its content exceeds in two preparations (with bamboo and alga) the permissible limit of 0.10 mg/kg. There were statistically significant differences in the occurrence of mercury depending on the herbal ingredient in the supplement. The lowest content was found in the preparation with Tanacetum parthenium and the highest with bamboo shoots. The mercury content in the tested herbal supplements was statistically significant in the form of a supplement-a tablet and a capsule. Daily, weekly, monthly, and yearly consumption of mercury with examined supplements was calculated-the results did not exceed the PTWI-provisional tolerable weekly intake of mercury. To increase consumer safety, it is imperative to conduct further research on dietary supplements and implement a stricter quality control of the dietary supplements.

  6. Assessment of mercury content in Panga (Pangasius hypophthalmus).

    Science.gov (United States)

    Rodríguez, María; Gutiérrez, Ángel J; Rodríguez, Natividad; Rubio, Carmen; Paz, Soraya; Martín, Verónica; Revert, Consuelo; Hardisson, Arturo

    2018-04-01

    Panga (Pangasius hypophthalmus), originating from Vietnam, is one of the most consumed fish because of its low cost, mild taste and presentation (fillets without skin and bones). Nevertheless, due to the high levels of contamination of the rivers where it lives, and to the fact that the panga is a predator, whereby it will accumulate a higher mercury concentration, the main objectives of the present study were to evaluate the toxic risk from mercury ingestion as a result of the consumption of this fish. A total of 80 frozen panga samples natural and marinade from different commercial establishments have been analyzed using cold vapour atomic absorption spectrophotometry (CV-AAS). The results obtained show a wide range of mercury concentrations between 0.10 and 0.69 mg/kg, with an average value of 0.22 mg/kg. In addition, it has been found that the average mercury concentration in the marinated presentation (0.18 mg/kg) is higher than that obtained in the natural panga (0.16 mg/kg). However, no significant differences were found between commercial establishments or in the presentation formats, with the conclusion that they did not influence the mercury content in the samples. Assuming a weekly consumption of 350 g of panga, the contribution rate to Tolerable Weekly Intake (TWI) of mercury (4 μg/kg bw/week) is 32% and