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Sample records for cadmium chromium mercury

  1. Survey of cosmetics for arsenic, cadmium, chromium, cobalt, lead, mercury, and nickel content.

    Science.gov (United States)

    Hepp, Nancy M; Mindak, William R; Gasper, John W; Thompson, Christopher B; Barrows, Julie N

    2014-01-01

    As part of efforts to assess amounts of inorganic element contamination in cosmetics, the U.S. Food and Drug Administration contracted a private laboratory to determine the total content of seven potentially toxic or allergenic elements in 150 cosmetic products of 12 types (eye shadows, blushes, lipsticks, three types of lotions, mascaras, foundations, body powders, compact powders, shaving creams, and face paints). Samples were analyzed for arsenic, cadmium, chromium, cobalt, lead, and nickel by inductively coupled plasma-mass spectrometry and for mercury by cold vapor atomic fluorescence spectrometry. The methods used to determine the elements were tested for validity by using standard reference materials with matrices similar to the cosmetic types. The cosmetic products were found to contain median values of 0.21 mg/kg arsenic, 3.1 mg/kg chromium, 0.91 mg/kg cobalt, 0.85 mg/kg lead, and 2.7 mg/kg nickel. The median values for cadmium and mercury were below the limits of detection of the methods. The contract requirements, testing procedures, and findings from the survey are described.

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

    Energy Technology Data Exchange (ETDEWEB)

    Tsipoura, Nellie [New Jersey Audubon Society, 11 Hardscrabble Road, Bernardsville, NJ 07924 (United States); Burger, Joanna, E-mail: burger@biology.rutgers.edu [Division of Life Sciences, 604 Allison Road, Piscataway, NJ 08854-8082 (United States); Environmental and Occupational Health Sciences Institute, Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ 08854 (United States); Newhouse, Michael [NJ Meadowlands Commission, One DeKorte Park Plaza, Lyndhurst, NJ 07071 (United States); Jeitner, Christian [Division of Life Sciences, 604 Allison Road, Piscataway, NJ 08854-8082 (United States); Environmental and Occupational Health Sciences Institute, Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ 08854 (United States); Gochfeld, Michael [Environmental and Occupational Health Sciences Institute, Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ 08854 (United States); Environmental and Occupational Medicine. Robert Wood Johnson Medical School, 170 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Mizrahi, David [New Jersey Audubon Society, 11 Hardscrabble Road, Bernardsville, NJ 07924 (United States)

    2011-08-15

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

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

    Science.gov (United States)

    Akçay, Nilay; Batan, Nevzat; Ćinar, Yunus

    2016-04-01

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

  4. Concentrations of Mercury, Lead, Chromium, Cadmium, Arsenic and Aluminum in Irrigation Water Wells and Wastewaters Used for Agriculture in Mashhad, Northeastern Iran

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    M Sadeghi

    2013-04-01

    Full Text Available Background: Contamination of water by toxic chemicals has become commonly recognized as an environmental concern. Based on our clinical observation in Mashhad, northeastern Iran, many people might be at risk of exposure to high concentrations of toxic heavy metals in water. Because wastewater effluents as well as water wells have been commonly used for irrigation over the past decades, there has been some concern on the toxic metal exposure of crops and vegetables irrigated with the contaminated water.Objective: To measure the concentrations of mercury, lead, chromium, cadmium, arsenic and aluminium in irrigation water wells and wastewaters used for agriculture in Mashhad, northeastern Iran.Methods: 36 samples were taken from irrigation water wells and a wastewater refinery in North of Mashhad at four times—May 2008, March 2009, and June and July 2010. Atomic absorption spectrometry was used to measure the concentration of toxic metals. Graphite furnace was used for the measurement of lead, chromium, cadmium and aluminum. Mercury and arsenic concentrations were measured by mercury/hydride system.Results: Chromium, cadmium, lead and arsenic concentrations in the samples were within the standard range. The mean±SD concentration of mercury in irrigation wells (1.02±0.40 μg/L exceeded the FAO maximum permissible levels. The aluminum concentration in irrigation water varied significantly from month to month (p=0.03. All wastewater samples contained high mercury concentrations (6.64±2.53 μg/L.Conclusion: For high mercury and aluminum concentrations, the water sources studied should not be used for agricultural use. Regular monitoring of the level of heavy metals in water and employing the necessary environmental interventions in this area are strongly recommended.

  5. Mercury, arsenic, cadmium, chromium lead, and selenium in feathers of pigeon guillemots (Cepphus columba) from Prince William Sound and the Aleutian Islands of Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Burger, Joanna [Division of Life Sciences, Rutgers University, 604 Allison Road, Piscataway, New Jersey 08854-8082 (United States); Consortium for Risk Evaluation with Stakeholder Participation (CRESP), Piscataway, New Jersey 08854 (United States); Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, New Jersey 08854 (United States)], E-mail: burger@biology.rutgers.edu; Gochfeld, Michael [Consortium for Risk Evaluation with Stakeholder Participation (CRESP), Piscataway, New Jersey 08854 (United States); Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, New Jersey 08854 (United States); Environmental and Occupational Medicine, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey 08854 (United States); Sullivan, Kelsey [U.S. Fish and Wildlife Service, 1011 East Tudor Road, Anchorage, Alaska 99503 (United States); P.O. Box 801, Bethel, Maine, 04217 (United States); Irons, David [U.S. Fish and Wildlife Service, 1011 East Tudor Road, Anchorage, Alaska 99503 (United States)

    2007-11-15

    Arsenic, cadmium, chromium, lead, manganese, mercury and selenium were analyzed in the feathers of pigeon guillemots (Cepphus columba) from breeding colonies in Prince William Sound and in the Aleutian Islands (Amchitka, Kiska) to test the null hypothesis that there were no differences in metal levels as a function of location, gender, or whether the birds were from oiled or unoiled areas in Prince William Sound. Birds from locations with oil from the Exxon Valdez Oil Spill in the environment had higher levels of cadmium and lead than those from unoiled places in Prince William Sound, but otherwise there were no differences in metal levels in feathers. The feathers of pigeon guillemots from Prince William Sound had significantly higher levels of cadmium and manganese, but significantly lower levels of mercury than those from Amchitka or Kiska in the Aleutians. Amchitka had the lowest levels of chromium, and Kiska had the highest levels of selenium. There were few gender-related differences, although females had higher levels of mercury and selenium in their feathers than did males. The levels of most metals are below the known effects levels, except for mercury and selenium, which are high enough to potentially pose a risk to pigeon guillemots and to their predators.

  6. Critical trace elements in brewing technology. Pt. 2. Occurrence of arsenic, lead, cadmium, chromium, mercury and selenium in beer

    Energy Technology Data Exchange (ETDEWEB)

    Donhauser, S.; Wagner, D.; Jacob, F.

    1987-01-01

    A study of 100 beer samples gave a representative cross-section of the amount of critical trace elements in beers. The following average values were obtained. Arsenic 6,4 ..mu..g/l, chromium 7,5 ..mu..g/l, lead 1,6 ..mu..g/l, mercury < 0,5 ..mu..g/l, cadmium 0,2 ..mu..g/l, selenium 1,2 ..mu..g/l. The drinking water limit value was just exceeded with two beers and by more than two-fold with one beer. The concentration of elements in the other beers were mostly well below the legal norm of the drinking water regulations. Separation of the samples according to beer container showed no significant difference with respect to trace element content between glass bottles and cans. Only 3 piece tinplate cans with a soldered body seam, which must have been damaged, contained beer with higher lead values. The trace element content of individual beer types did not differ from one another. An evaluation of the weakly intake of thee critical elements in beer, using these measured values, shows no cause for concern about health. (orig.)

  7. Mercury, Lead, Cadmium, Arsenic, Chromium and Selenium in Feathers of Shorebirds during Migrating through Delaware Bay, New Jersey: Comparing the 1990s and 2011/2012

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    Joanna Burger

    2015-02-01

    Full Text Available Understanding temporal changes in contaminant levels in coastal environments requires comparing levels of contaminants from the same species from different time periods, particularly if species are declining. Several species of shorebirds migrating through Delaware Bay have declined from the 1980s to the present. To evaluate some contaminants as cause for the declines, we examine levels of mercury, lead, cadmium, arsenic, chromium and selenium in feathers of red knot (Calidris canutus, N = 46 individuals, semipalmated sandpiper (Calidris pusilla, N = 70 and sanderling (Calidris alba, N = 32 migrating through Delaware Bay, New Jersey, USA, from 1991 to 1992 (N = 40, 1995 (N = 28, and 2011–2012 (N = 80 to determine if levels have changed. We found: (1 arsenic, chromium, and lead increased in red knot and decreased in semipalmated sandpiper; (2 cadmium decreased in semipalmated sandpipers; (3 mercury decreased in red knot and sanderlings; (4 selenium decreased in red knot and increased in semipalmated sandpipers. In 2011/2012 there were significant interspecific differences for arsenic, mercury and selenium. Except for selenium, the element levels were well below levels reported for feathers of other species. The levels in feathers in red knots, sanderling, and semipalmated sandpipers from Delaware Bay in 2011/2012 were well below levels in feathers that are associated with effect levels, except for selenium. Selenium levels ranged from 3.0 µg·g−1 dry weight to 5.8 µg·g−1 (semipalmated sandpiper, within the range known to cause adverse effects, suggesting the need for further examination of selenium levels in birds. The levels of all elements were well below those reported for other marine species, except for selenium, which was near levels suggesting possible toxic effects.

  8. Bioaccumulation of mercury, cadmium, zinc, chromium, and lead in muscle, liver, and spleen tissues of a large commercially valuable catfish species from Brazil

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    Fábio P. Arantes

    2016-03-01

    Full Text Available The increasing amounts of heavy metals entering aquatic environments can result in high accumulation levels of these contaminants in fish and their consumers, which pose a serious risk to ecosystems and human health. We investigated the concentrations of mercury (Hg, cadmium (Cd, zinc (Zn, chromium (Cr, and lead (Pb in muscle, liver, and spleen tissues of Pseudoplatystoma corruscans specimens collected from two sites on the Paraopeba River, Brazil. The level of heavy metals concentrations in the tissues was often higher in viscera (i.e. liver and spleen than in muscle, and thus, the viscera should not be considered for human consumption. Correlations between metal concentrations and fish size were not significant. Although the levels of muscle bioaccumulation of Hg, Cd, Zn, Cr, and Pb, generally do not exceed the safe levels for human consumption, the constant presence of heavy metals in concentrations near those limits considered safe for human consumption, is a reason for concern, and populations who constantly consume fish from polluted rivers should be warned. Our findings also indicate that in a river network where certain areas are connected to other areas with high rates of environmental pollutants, people should be cautious about the regular consumption of fish, even when the fish consumed are caught in stretches of the basin where contamination levels are considered low, since many of the freshwater fish with high commercial value, such as the catfish surubim, are migratory.

  9. Lead, mercury, and cadmium in breast milk

    OpenAIRE

    Kadriye Yurdakök

    2015-01-01

    Toxic heavy metals are the major source of environmental pollution in this new millennium. Lead, mercury, and cadmium are the most common toxic heavy metals in the environment. There is no known function of these toxic heavy metals in the human body. In females, toxic heavy metals can be accumulated in maternal body before pregnancy and may be transferred to fetus through placenta and later, via breast milk. Lead previously accumulated in maternal bones can be mobilized along with calcium in ...

  10. Mercury Cadmium Selenide for Infrared Detection

    Science.gov (United States)

    2013-06-01

    were grown using elemental mercury (Hg), cadmium (Cd), and selenium (Se) sources. The beam equiva- lent pressure ( BEP ) emanating from all sources was...flux), the BEP measured for the cracker source was found to vary with the cracking zone temperature, tracking with the data found in Ref. 7. This sug...The Se BEP measured for the typical cracking zone temperature of 800 C was found to be close to a factor of two lower than at the typical effusion cell

  11. Application of Zeeman graphite furnace atomic absorption spectrometry with high-frequency modulation polarization for the direct determination of aluminum, beryllium, cadmium, chromium, mercury, manganese, nickel, lead, and thallium in human blood.

    Science.gov (United States)

    Ivanenko, Natalya B; Solovyev, Nikolay D; Ivanenko, Anatoly A; Ganeev, Alexander A

    2012-10-01

    Determination of aluminum (Al), beryllium (Be), cadmium (Cd), chromium (Cr), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), and thallium (Tl) concentrations in human blood using high-frequency modulation polarization Zeeman graphite furnace atomic absorption spectrometry (GFAAS) was performed. No sample digestion was used in the current study. Blood samples were diluted with deionized water or 0.1 % (m/v) Triton X-100 solution for Tl. Dilution factors ranged from 1/5 per volume for Be and Tl to 1/20 per volume for Cd and Pb. For Tl, Cd, and Hg, noble metals (gold, platinum, rhodium, etc.) were applied as surface modifiers. To mitigate chloride interference, 2 % (m/v) solution of NH(4)NO(3) was used as matrix modifier for Tl and Ni assessment. The use of Pd(NO(3))(2) as oxidative modifier was necessary for blood Hg and Tl measurement. Validation of the methods was performed by analyzing two-level reference material Seronorm. The precision of the designed methods as relative SD was between 4 and 12 % (middle of a dynamic range) depending on the element. For additional validation, spiked blood samples were analyzed. Limits of detection (LoDs, 3σ, n = 10) for undiluted blood samples were 2.0 μg L(-1) for Al, 0.08 μg L(-1) for Be, 0.10 μg L(-1) for Cd, 2.2 μg L(-1) for Cr, 7 μg L(-1) for Hg, 0.4 μg L(-1) for Mn, 2.3 μg L(-1) for Ni, 3.4 μg L(-1) for Pb, and 0.5 μg L(-1) for Tl. The LoDs achieved allowed determination of Al, Cd, Cr, Mn, Ni, and Pb at both toxic and background levels. Be, Hg, and Tl could be reliably measured at toxic levels only. The methods developed are used for clinical diagnostics and biological monitoring of work-related exposure.

  12. Bioremediation of the soils contaminated with cadmium and chromium, by the earthworm Eisenia fetida.

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    E Aseman

    2016-01-01

    Results: There was a significant correlation between the reduction of chromium and cadmium metals in the soils and the accumulation of chromium and cadmium metals in the worm’s body. A significant decline of chromium levels of the soil was observed in the days 21 and 42 during the study compared to the initial amount of 0.1 mg/g. On the other hand, chromium concentration of the soil decreased from 0.14 to 0.1 mg/g after 42 days. Conclusion: said the research indicated that increased mortality of worms in the soil at a concentration of 0.08 mg/g of chromium, using the worms for bioremediation is not recommended. Although, this method is effective to remove cadmium from the soils having cadmium with concentrations of 0.04 and 0.08 mg/g but it needs further investigation.

  13. Ecotoxicological tests with cadmium and chromium using postlarvae of silverside Odontesthes (Austromenidia regia regia Hildebrand

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    Giovana Vera

    2014-06-01

    Full Text Available In the present paper, the mean effective concentrations (EC50% of cadmium (Cd+2 and chromium (Cr+6 using postlarvae of the silverside fish Odontesthes (Austromenidia regia regia were determined. The postlarvae were exposed to different concentrations of the metals, between 0,142 and 1,208 mg.L–1 of cadmium and between 0,53 and 33,74 mg.L–1 of chromium. The mean effective concentrations (EC50% obtained were 0,648 mg.L–1 of cadmium (at 96 h and 2,68 mg.L–1 of chromium (at 96 h. Comparatively, cadmium is more toxic than chromium, and silverside is more tolerant than other organisms.

  14. Cadmium, Mercury and Lead in Hypericum perforatum L. collected in Western Serbia

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    Đurović D.

    2013-04-01

    Full Text Available Wild population of Hypericum perforatum growing in Western Serbia was analyzed for the content of important environmental pollutants cadmium, mercury and lead. Metal contents were determined by inductively coupled plasma optical emission spectrometry. Obtained results showed that levels of mercury and lead were under while cadmium concentrations exceeded limits recommended for medicinal plants. High levels of cadmium in investigated plants can be the result of soil enriched with cadmium as well as the ability of Hypericum perforatum to accumulate cadmium.

  15. Lead, mercury, and cadmium in breast milk

    Directory of Open Access Journals (Sweden)

    Kadriye Yurdakök

    2015-10-01

    Full Text Available Toxic heavy metals are the major source of environmental pollution in this new millennium. Lead, mercury, and cadmium are the most common toxic heavy metals in the environment. There is no known function of these toxic heavy metals in the human body. In females, toxic heavy metals can be accumulated in maternal body before pregnancy and may be transferred to fetus through placenta and later, via breast milk. Lead previously accumulated in maternal bones can be mobilized along with calcium in order to meet increased calcium needs of the fetus in pregnant women and for the calcium needs in human milk during lactation. Human fetus and infants are susceptible to heavy metal toxicity passing through placenta and breastmilk due to rapid growth and development of organs and tissues, especially central nervous system. However most of the damage is already done by the time the infant is born. Intrauterine lead exposure can cause growth retardation, cognitive dysfunction, low IQ scores on ability tests, and low performance in school. Biological samples, such as umbilical cord blood and breast milk, and less commonly infant hair, are used for biomonitoring of intra-uterine exposure to these toxic chemicals. Although toxic metals and other pollutants may be excreted into breast milk, their effects are unknown and this topic is subject of a growing body of research. Despite the possibility of harm from environmental contaminants in breast milk, breastfeeding is still recommended as the best infant feeding method. In fact, the species-specific components present in breast milk protect infants against infections; promote immune and neurologic system development; and may decrease the risk of disease, including allergies, obesity, insulin-dependent diabetes mellitus, inflammatory bowel disease, and sudden infant death syndrome. Breastfeeding also facilitates maternal-infant attachment. The potential risk of environmental contaminants that can be transferred from

  16. Bioremediation of the Soils Contaminated with Cadmium and Chromium, by the Earthworm Eisenia fetida

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    Elham Aseman- Bashiz1

    2014-07-01

    Full Text Available One of the most important environmental problems in the world is the soils contamination by heavy metals in the industrial areas, and especially the contamination of the agricultural lands. The use of earthworms to bioremediate the soils results in reducing the pollutants concentration through a bioaccumulation mechanism on the contaminants in the earthworm's body. Hence, the present study aimed to prove the biological effectiveness of Eisenia fetida earthworms in bioremediation the soils contaminated with chromium and cadmium. Concentration of chromium and cadmium pollution in soil was determined to be 0.04 mg/g and 0.08 mg/g respectively. 30 worms were added to 500 g soil samples. Chromium and cadmium concentration in soil and in the body of worms was measured at two time periods of 21 and 42 days. To measure the concentration of chromium and cadmium we used ICP spectrometry. Software in usage was SPSS version 17. There was a significant correlation between the reduction of chromium and cadmium metals in the soils and the accumulation of chromium and cadmium metals in the worm’s body. A significant decline of chromium levels of the soil was observed in the days 21 and 42 during the study compared to initial amount of 0.1 mg/g. on the other hand chromium concentration of the soil decreased from 0.14 mg/g to 0.1 mg/g after 42 days. Comparison of mortality in two different time periods showed that by passing the time and by increase in soil chromium and cadmium concentrations the death toll of worms rises. The increased mortality of worms in the soil at a concentration of 0.08 mg/g of chromium, say that using the worms for bioremediation is not recommended at such concentration of chromium but using the worms for the removal of cadmium at concentrations of 0.04 mg/g and 0.08 mg/g in the soil is recommended.

  17. Inhibition by chromium and cadmium of anaerobic acidogenesis.

    Science.gov (United States)

    Yu, H Q; Fang, H H

    2001-01-01

    The effects of chromium (III) and cadmium on the anaerobic acidogenesis of a simulated dairy waste were examined using serum vials. At Cd dosages less than 20 mg/l, the acidogenesis process was enhanced by the dosage, resulting in a higher degree of acidification, protein conversion, and hydrogen production than the control. At dosages over 20-mg/l, Cd inhibited the acidogenesis. The Cr (III) dosage of 5 mg/l reduced overall volatile fatty acid and alcohol generation, degree of acidification, conversions of lactose, lipid and protein, and total biogas production, with the exception of accumulation of hydrogen and propionate. At dosages exceeding 5 mg/l, Cr (III) had a severe inhibition on the acidogenesis. The Cd concentrations which caused a 50% reduction in total volatile fatty acid and alcohol production, degree of acidification and cumulative gas production were higher than the corresponding values caused by Cr (III), suggesting that Cr (III) was more toxic to acidogenic bacteria than Cd.

  18. Thyrotoxicity of the Chlorides of Cadmium and Mercury in Rabbit

    Institute of Scientific and Technical Information of China (English)

    NINAGHOSH; SHELLEYBHATTACHARYA

    1992-01-01

    Exposure to heavy metals such as cadmium and mercury is of immediate environmental concern.The present study was aimed at establishing a direct relationship between heavy metal poisoning and thyroid dysfunction.Cadmium and mercury treatment at LD50 levels resulted in severe thyrotoxicosis in the rabbit.Within 24h of intramuscular administration of cadmium chloride 15 mg·kg-1 body weight(bw)and mercury chloride20mg·kg-1 bw,thyroid peroxidase activity increased significantly over the control with a concomitant rise in the triiodothyronie(T3)titre.On the other hand,there was a remarkable fall in the thyroxine(T4)level,and the T3,T4 ratio was high as compared with the control.Evidence indicates that acute heavy metal lethality will induce immediate hyperthyroidism.It is suggested that T3-toxicosis may be produced by a preferential synthesis of T3 and/or preferential deiodination of T4 to T3.Measurement of T3 and T4 levels may thus e utilized as a reliable indicator of heavy metal lethality.

  19. Translocation of mercury and cadmium into the fruiting bodies of six higher fungi

    Energy Technology Data Exchange (ETDEWEB)

    Brunnert, H.; Zadrazil, F.

    1983-01-01

    The species- and metal-specific translocation of cadmium and mercury from the substrate to the fruiting bodies of 6 higher fungi has been investigated. The 6 species differed greatly in their ability to translocate cadmium and mercury. The highest translocation rates displayed Pleurotus flabellatus: 75.0% of the applied cadmium and 38.5% of the mercury could be recovered from the fruiting bodies. High translocation rates also found with Pleurotus ostreatus (19.3 and 38.5% for cadmium and mercury, respectively). This compares with only 1.27% of cadmium and 8.42% of mercury in Agaricus bisporus or 3.71% of cadmium and 3.63% of mercury in Pleurotus sajor caju. For Agaricus bisporus it was shown that there was proportionality of translocation over a 1:10 concentration range. In 4 out of 6 species there was a tendency towards higher heavy metal contents in later crops, when calculated on the basis of ..mu..g/g of dry fruiting body. In 4 out of 6 more mercury than cadmium was translocated into the fruiting bodies, the Cd/Hg ratios being 6.6, 2.0, 5.6, and 3.2, respectively. In Pleurotus sajor caju the ratio was about 1. Only in Pleurotus flabellatus more cadmium than mercury was found in the fruiting bodies (Cd/Hg ratio 0.65).

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

    Science.gov (United States)

    Recknagel, Sebastian; Radant, Hendrik; Kohlmeyer, Regina

    2014-01-01

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

  1. THE EVALUATION OF NICKEL, CHROMIUM, LEAD AND MERCURY CONTENT IN SWEET CORN

    OpenAIRE

    Miriama Kopernická; Tomáš Tóth; Ľuboš Harangozo; Beáta Volnová; Petra Kavalcová; Ádám Elek

    2015-01-01

    In the framework of monitoring, we have focused on the analysis of the levels of nickel, chromium, lead and mercury in 9 samples of sweet corn (frozen and canned) from the commercial network of the Slovak Republic. Homogenised samples of sweet corn were mineralized using microwave digestion unit MARS X-press and next analysed by atomic absorption spectrometer VARIAN 240 FS for tested metal concentration, excluding mercury which was was determined by automatic mercury analyser AMA 254.Nickel c...

  2. Arsenic, Cadmium, Lead, and Mercury in Sweat: A Systematic Review

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    Margaret E. Sears

    2012-01-01

    Full Text Available Arsenic, cadmium, lead, and mercury exposures are ubiquitous. These toxic elements have no physiological benefits, engendering interest in minimizing body burden. The physiological process of sweating has long been regarded as “cleansing” and of low risk. Reports of toxicant levels in sweat were sought in Medline, Embase, Toxline, Biosis, and AMED as well as reference lists and grey literature, from inception to March 22, 2011. Of 122 records identified, 24 were included in evidence synthesis. Populations, and sweat collection methods and concentrations varied widely. In individuals with higher exposure or body burden, sweat generally exceeded plasma or urine concentrations, and dermal could match or surpass urinary daily excretion. Arsenic dermal excretion was severalfold higher in arsenic-exposed individuals than in unexposed controls. Cadmium was more concentrated in sweat than in blood plasma. Sweat lead was associated with high-molecular-weight molecules, and in an interventional study, levels were higher with endurance compared with intensive exercise. Mercury levels normalized with repeated saunas in a case report. Sweating deserves consideration for toxic element detoxification. Research including appropriately sized trials is needed to establish safe, effective therapeutic protocols.

  3. Adsorción de cadmio, cromo y mercurio en suelos del Valle del Cauca a varios valores de pH Cadmium, chromium and mercury adsorption on Cauca Valley soils as a function of pH

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    García O. Álvaro

    1991-12-01

    were collected and prepared for sorption experiments adjusting the pH to 5.7,6.5 and 7.8 values using, 1,4 and 12% acetic acid or 0.01 N NaOH. Six saturating solution of each metal (0.0, 0.28, 0.56, 1.12 and 2.25 mg L-1 were added to 0.25 g air dried and ground to pass a 2-mm sieve soil samples. The soil solution suspensions were shaken for 25 minutes and then extracted with 0.01N HC1. Cadmium; Cr and Hg concentrations were determined by atomic absorption spectrofotometry. The difference between the initial and final metal solution concentration was considered to be soil adsorbed and the amount 0.01 N HC1 extracted as the metal retained by the soil. Cadmium adsorption in all the soils was higher at neutral or alkaline pH values due to the predominance of divalent solubles or insoluble metalanion complexes formed in the soil at pH values higter than 7.0. The Cr and Hg adsorption is higher at acid values of pH due to the formation of complexes with the organic matter (chelation or with Fe, Al or Mn hydrous oxids wich are favoreced at this pH values. The lower 0.01N HC1 extraction (higher retention was observed at pH values 6.4-6.6 in all the soils suggesting that in this range of pH this heavy metals are strongly adsorbed by the exchange complex and are not available to plants.

  4. Cadmium, mercury, zinc and selenium in ringed seals (Phoca hispida from Greenland and Svalbard

    Directory of Open Access Journals (Sweden)

    Run Dietz

    1998-06-01

    Full Text Available Muscle, liver, and kidney tissue from 456 ringed seals (Phoca hispida from eight areas in Greenland were analysed for cadmium, mercury, zinc and selenium. In general, cadmium concentrations were high in liver and kidney tissue, with geometric means of 7.79 and 33.5 μg/g (all data on wet weight basis, respectively. Muscle levels were considerably lower, at 0.067 μg/g. The concentration of mercury was relatively high in liver tissue with a geometric mean of 2.59 μg/g. Muscle and kidney mercury levels were somewhat lower, with geometric means of 0.210 and 0.956 μg/g, respectively. Cadmium and mercury levels were strongly dependent upon age and sampling area, as well as the interaction combinations, indicating that the accumulation of cadmium and mercury varies with age and area. Mercury accumulated in all three tissues throughout life, whereas cadmium in liver and kidneys peaked in the age group 5-10 years old where after it dropped significantly. Cadmium levels showed a tendency towards higher concentrations in the northern municipalities, which may be due to the higher cadmium levels in certain prey items in the northern areas. Mercury levels were higher in seals from East Greenland compared to West Greenland. Variations in feeding habits probably explain some of the differences in levels of cadmium and mercury in ringed seals from different geographical areas. Cadmium concentrations were correlated (both pairwise and partial in the three organs. This was true for mercury as well, whereas only half of the combinations were significant for zinc and selenium. Cadmium was strongly correlated to mercury in all three tissues and zinc only in liver and kidneys. Mercury was only correlated to selenium in liver and not to zinc. High concentrations of cadmium were found in the bile from 58 ringed seals, and were about 10-fold higher than in muscle. The concentration of mercury in bile was relatively low, being only one third of the

  5. Cadmium, lead and mercury exposure in non smoking pregnant women

    Energy Technology Data Exchange (ETDEWEB)

    Hinwood, A.L., E-mail: a.hinwood@ecu.edu.au [Centre for Ecosystem Management, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027 (Australia); Callan, A.C.; Ramalingam, M.; Boyce, M. [Centre for Ecosystem Management, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027 (Australia); Heyworth, J. [School Population Health, The University of Western Australia, 35 Stirling Highway Crawley, WA 6009 (Australia); McCafferty, P. [ChemCentre, PO Box 1250, Bentley, WA 6983 (Australia); Odland, J.Ø. [Department of Community Medicine, University of Tromsø, N-9037 Tromsø (Norway)

    2013-10-15

    Recent literature suggests that exposure to low concentrations of heavy metals may affect both maternal and child health. This study aimed to determine the biological heavy metals concentrations of pregnant women as well as environmental and dietary factors that may influence exposure concentrations. One hundred and seventy three pregnant women were recruited from Western Australia, each providing a sample of blood, first morning void urine, residential soil, dust and drinking water samples. Participants also completed a questionnaire which included a food frequency component. All biological and environmental samples were analysed for heavy metals using ICP-MS. Biological and environmental concentrations of lead and mercury were generally low (Median Pb Drinking Water (DW) 0.04 µg/L; Pb soil <3.0 µg/g; Pb dust 16.5 µg/g; Pb blood 3.67 µg/L; Pb urine 0.55; µg/L Hg DW <0.03; Hg soil <1.0 µg/g; Hg dust <1.0 µg/g; Hg blood 0.46 µg/L; Hg urine <0.40 µg/L). Cadmium concentrations were low in environmental samples (Median CdDW 0.02 µg/L; Cdsoil <0.30 ug/g; Cddust <0.30) but elevated in urine samples (Median 0.55 µg/L, creatinine corrected 0.70 µg/g (range <0.2–7.06 µg/g creatinine) compared with other studies of pregnant women. Predictors of increased biological metals concentrations in regression models for blood cadmium were residing in the Great Southern region of Western Australia and not using iron/folic acid supplements and for urinary cadmium was having lower household annual income. However, these factors explained little of the variation in respective biological metals concentrations. The importance of establishing factors that influence low human exposure concentrations is becoming critical in efforts to reduce exposures and hence the potential for adverse health effects. -- Highlights: • Biological heavy metals concentrations in women in their 3rd trimester of pregnancy. • Exposure assessment including environmental, lifestyle and activity

  6. Megapixel mercury cadmium telluride focal plane arrays for infrared imaging out to 12 microns Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the fabrication of large format, long wave infrared (LWIR) mercury cadmium telluride (HgCdTe or MCT) detector arrays where the cutoff wavelength is...

  7. Mercury Cadmium Telluride Photoconductive Long Wave Infrared Linear Array Detectors

    Directory of Open Access Journals (Sweden)

    Risal Singh

    2003-07-01

    Full Text Available Mercury cadmium telluride (Hg1-x, CdxTe (MCT photoconductive long wave infrared linear arrays are still in demand due to several advantages. The linear array technology is well established, easier, economical and is quite relevant to thermal imaging even today. The scan thermal imaging systems based on this technology offer wider field of view coverage and capacity for higher resolution in the scan direction relative to staring systems that use expensive and yet to mature focal plane array detector technology. A critical review on photoconductive n-Hg1-x CdxTe linear array detector technology for the long wave infrared range has been presented. The emphasis lies on detector design and processing technology. The critical issues of diffusion and drift effects, Hi-Lo and heterostructure blocking contacts, surface passivation, and other related aspects have been considered from the detector design angle. The device processing technology aspects are of vital importance

  8. Soil washing of chromium- and cadmium-contaminated sludge using acids and ethylenediaminetetra acetic acid chelating agent.

    Science.gov (United States)

    Gitipour, Saeid; Ahmadi, Soheil; Madadian, Edris; Ardestani, Mojtaba

    2016-01-01

    In this research, the effect of soil washing in the removal of chromium- and cadmium-contaminated sludge samples collected from Pond 2 of the Tehran Oil Refinery was investigated. These metals are considered as hazardous substances for human health and the environment. The carcinogenicity of chromate dust has been established for a long time. Cadmium is also a potential environmental toxicant. This study was carried out by collecting sludge samples from different locations in Pond 2. Soil washing was conducted to treat the samples. Chemical agents, such as acetic acid, ethylenediaminetetra acetic acid (EDTA) and hydrochloric acid, were used as washing solutions to remove chromium and cadmium from sludge samples. The results of this study indicated that the highest removal efficiencies from the sludge samples were achieved using a 0.3 M HCl solution with 82.69% and 74.47% for chromium and cadmium, respectively. EDTA (0.1 M) in the best condition extracted 66.81% of cadmium and 72.52% of chromium from the sludges. The lowest efficiency values for the samples, however, were achieved using 3 M acetic acid with 41.7% and 46.96% removals for cadmium and chromium, respectively. The analysis of washed sludge indicated that the heavy metals removal decreased in the order of 3 M acetic acid acid appears to offer a greater potential as a washing agent in remediating the sludge samples.

  9. Critical loads of Cadmium, Lead and Mercury and their exceedances in Europe

    NARCIS (Netherlands)

    Hettelingh, J.P.; Schutze, G.; Vries, W. de; Denier van der Gon, H.A.C.; Ilyin, I.; Reinds, G.J.; Slootweg, J.; Travnikov, O.

    2015-01-01

    Cadmium (Cd), lead (Pb) and mercury (Hg) are known to be transported over relatively long distances from their sources. Deposited metals may accumulate over time in soils and catchments, and then follow varying pathways to endpoints in humans and the environment. Cadmium and lead, that are emitted p

  10. Effect of cadmium and chromium on the intestinal absorption of glucose in the snakehead fish, Channa punctatus.

    Science.gov (United States)

    Sastry, K V; Sunita, K

    1982-02-01

    The effect of five concentrations of cadmium and chromium (10 mM, 1 mM, 0.1 mM, 0.01 mM and 0.001 mM) on the rate of absorption of glucose from the intestine of te snakehead fish, channa punctatus, was studied at 23 degrees C. All concentrations of cadmium decreased the rate of glucose transport. Maximum decrease was recorded with 10 mM of cadmium. The rate of transport decreased with an increase in the concentration of cadmium used. Chromium increased glucose absorption rate at all concentrations examined; the highest rate of absorption occurred at 0.001 mM of chromium.

  11. 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.

  12. THE EVALUATION OF NICKEL, CHROMIUM, LEAD AND MERCURY CONTENT IN SWEET CORN

    Directory of Open Access Journals (Sweden)

    Miriama Kopernická

    2015-02-01

    Full Text Available In the framework of monitoring, we have focused on the analysis of the levels of nickel, chromium, lead and mercury in 9 samples of sweet corn (frozen and canned from the commercial network of the Slovak Republic. Homogenised samples of sweet corn were mineralized using microwave digestion unit MARS X-press and next analysed by atomic absorption spectrometer VARIAN 240 FS for tested metal concentration, excluding mercury which was was determined by automatic mercury analyser AMA 254.Nickel content in all samples was in the range of 0.376 – 0.556 mg.kg-1, chromium content was 0.088 – 0.546 mg.kg-1, lead content was 0.054 – 0.146 mg.kg-1 and mercury content was 0.000013 – 0.011458 mg.kg-1. The measured values have been compared with the limit values set out legislation for the maximum quantity of hazardous elements according to the Food Code of the Slovak Republic. From the point of view of the sanitary evaluation, the content of nickel, chromium, lead and mercury were not exceeded in either sample.

  13. Human exposure to mercury, lead and cadmium through consumption of canned mackerel, tuna, pilchard and sardine.

    Science.gov (United States)

    Okyere, H; Voegborlo, R B; Agorku, S E

    2015-07-15

    Total mercury (Hg), cadmium (Cd) and lead (Pb) concentrations were determined in canned fish on the Ghanaian market. Total mercury was determined using an automatic mercury analyzer while cadmium and lead levels were determined by flame atomic absorption spectrophotometry. The metal contents in the samples, expressed in μg g(-1) (wet weight), varied from canned fish from the Ghanaian market have concentrations well below the permissible FAO/WHO for these toxic metals. Thus considering the Provisional Tolerable Weekly Intake (PTWI) of Hg, Pb and Cd the levels obtained in this study are unlikely to constitute a significant exposure to the public through consumption of moderate amounts.

  14. Arsenic and mercury tolerance and cadmium sensitivity in Arabidopsis plants expressing bacterial gamma-glutamylcysteine synthetase.

    Science.gov (United States)

    Li, Yujing; Dhankher, Om Parkash; Carreira, Laura; Balish, Rebecca S; Meagher, Richard B

    2005-06-01

    Cysteine sulfhydryl-rich peptide thiols are believed to play important roles in the detoxification of many heavy metals and metalloids such as arsenic, mercury, and cadmium in plants. The gamma-glutamylcysteine synthetase (gamma-ECS) catalyzes the synthesis of the dipeptidethiol gamma-glu-cys (gamma-EC), the first step in the biosynthesis of phytochelatins (PCs). Arabidopsis thaliana, engineered to express the bacterial gamma-ECS gene under control of a strong constitutive actin regulatory sequence (A2), expressed gamma-ECS at levels approaching 0.1% of total protein. In response to arsenic, mercury, and cadmium stresses, the levels of gamma-EC and its derivatives, glutathione (GSH) and PCs, were increased in the A2::ECS transgenic plants to three- to 20-fold higher concentrations than the increases that occurred in wild-type (WT). Compared to cadmium and mercury treatments, arsenic treatment most significantly increased levels of gamma-EC and PCs in both the A2::ECS transgenic and WT plants. The A2::ECS transgenic plants were highly resistant to arsenic and weakly resistant to mercury. Although exposure to cadmium produced three- to fivefold increases in levels of gamma-EC-related peptides in the A2::ECS lines, these plants were significantly more sensitive to Cd(II) than WT and trace levels of Cd(II) blocked resistance to arsenic and mercury. A few possible mechanisms for gamma-ECS-enhanced arsenic and mercury resistance and cadmium hypersensitivity are discussed.

  15. Calculation of critical loads for cadmium, lead and mercury; background document to a mapping manual on critical loads of cadmium, lead and mercury

    NARCIS (Netherlands)

    Vries, de W.; Schütze, G.; Lofts, S.; Tipping, E.; Meili, M.; Römkens, P.F.A.M.; Groenenberg, J.E.

    2005-01-01

    This report on heavy metals provides up-to-date methodologies to derive critical loads for the heavy metals cadmium (Cd), lead (Pb) and mercury (Hg) for both terrestrial and aquatic ecosystems. It presents background information to a Manual on Critical Loads for those metals. Focus is given to the m

  16. Magnetite nanoparticle (NP) uptake by wheat plants and its effect on cadmium and chromium toxicological behavior

    Energy Technology Data Exchange (ETDEWEB)

    López-Luna, J., E-mail: jlol_24@hotmail.com [Instituto de Estudios Ambientales, Universidad de la Sierra Juárez, Ixtlán de Juárez 68725, Oaxaca (Mexico); Silva-Silva, M.J. [Instituto de Estudios Ambientales, Universidad de la Sierra Juárez, Ixtlán de Juárez 68725, Oaxaca (Mexico); Martinez-Vargas, S. [Facultad de Ingeniería, Universidad Autónoma del Carmen, Ciudad del Carmen 24115, Campeche (Mexico); Mijangos-Ricardez, O.F. [Instituto de Estudios Ambientales, Universidad de la Sierra Juárez, Ixtlán de Juárez 68725, Oaxaca (Mexico); González-Chávez, M.C. [Colegio de Postgraduados en Ciencias Agrícolas, Carr. México–Texcoco km 36.5, Montecillo 56230, Estado de México (Mexico); Solís-Domínguez, F.A. [Facultad de Ingeniería, Universidad Autónoma de Baja California, Mexicali 21280, Baja California Norte (Mexico); Cuevas-Díaz, M.C. [Facultad de Ciencias Químicas, Universidad Veracruzana, Coatzacoalcos 96535, Veracruz (Mexico)

    2016-09-15

    The aim of this work was to assess the uptake of citrate-coated magnetite nanoparticles (NPs) by wheat plants and its effect on the bioaccumulation and toxicity of individual and joint Cd{sup 2+} and Cr{sup 6+} levels. Seven-day assays were conducted using quartz sand as the plant growth substrate. The endpoints measured were seed germination, root and shoot lengths, and heavy metal accumulation. Magnetite exhibited very low toxicity, regardless of the wheat seedling NP uptake and distribution into roots and shoots. The seed germination and shoot length were not sensitive enough, while the root length was a more sensitive toxicity endpoint. The root length of wheat seedlings exposed to individual metals decreased by 50% at 2.67 mg Cd{sup 2+} kg{sup −1} and 5.53 mg Cr{sup 6+} kg{sup −1}. However, when magnetite NPs (1000 mg kg{sup −1}) were added, the root length of the plants increased by 25 and 50%. Cd{sup 2+} and Cr{sup 6+} showed similar and noninteractive joint action, but strongly impaired the wheat seedlings. In contrast, an interactive infra-additive or antagonistic effect was observed upon adding magnetite NPs. Thus, cadmium and chromium accumulation in vegetable tissues was considerately diminished and the toxicity alleviated. - Highlights: • We assessed the effect of nanomagnetite on heavy metal toxicity in wheat plants. • Citrate-coated magnetite nanoparticles (NPs) exerted very low toxicity to plants. • Cadmium was more toxic than chromium and toxicity was mitigated by magnetite NPs. • Cadmium and chromium had a similar and noninteractive joint action on plants. • Metals showed an interactive infra-additive joint effect by adding magnetite NPs.

  17. Mercury, cadmium and arsenic contents of calcium dietary supplements.

    Science.gov (United States)

    Kim, Meehye

    2004-08-01

    The cadmium (Cd) and arsenic (As) contents of calcium (Ca) supplements available on the Korean market were determined by a graphite furnace atomic absorption spectrometer using Zeeman background correction and peak area mode after microwave digestion. The mercury (Hg) content of the supplements was measured using an Hg analyser. Recoveries ranged from 92 to 98% for Hg, Cd and As analyses. Fifty-five brands of Ca supplements were classified into seven categories based on the major composite: bone, milk, oyster/clam shell, egg shell, algae, shark cartilage and chelated. The means of Hg, Cd and As in Ca supplements were 0.01, 0.02, and 0.48 mg kg(-1), respectively. Ca supplements made of shark cartilage had the highest means of Hg (0.06 mg kg(-1)) and Cd (0.13 mg kg(-1)). The mean daily intakes of Hg and Cd from the supplement were estimated as about 0.1-0.2 microg, with both contributing less than 0.4% of provisional tolerable daily intakes set by the Food and Agricultural Organization/World Health Organization Joint Food Additive and Contaminants Committee.

  18. Determination of cadmium, chromium, lead and vanadium in six fish species from the Adriatic Sea.

    Science.gov (United States)

    Sepe, A; Ciaralli, L; Ciprotti, M; Giordano, R; Funari, E; Costantini, S

    2003-06-01

    Concentrations of cadmium, chromium, lead and vanadium were determined in samples of six fish species collected along the coast of the Adriatic Sea. The concentrations of the elements studied were generally low, often below the detection limits of the analytical methods. The highest values (microg x kg(-1) fresh weight) were observed, mainly in the central area of the Adriatic Sea, for anchovy (Cd 20.2, Cr 82.9, Pb 45.9, V 89.9), red mullet (Cd 3.1, Cr 31.0, Pb 36.0, V 79.1) and mackerel (Cd 7.7, Cr 28.0, Pb 11.4, V 43.5). The concentrations of cadmium and lead in all the species examined were below the maximum levels indicated by the European Community for these two elements in seafood, and also would lead to exposure levels lower than the provisional tolerable daily intakes suggested by the FAO/WHO for Cd (420 microg x week(-1) for a 60-kg person) and Pb (1500 microg x week(-1) for a 60-kg person). The concentration of chromium was lower than the recommended daily amount (50-200 microg x day(-1) for a 60-kg person) indicated by the US National Research Council. An 11-34% contribution to the daily vanadium ingestion with fish was calculated for the population of the Adriatic coast.

  19. Directional Solidification of Mercury Cadmium Telluride in Microgravity

    Science.gov (United States)

    Lechoczhy, Sandor L.; Gillies, Donald C.; Szofran, Frank R.; Watring, Dale A.

    1998-01-01

    Mercury cadmium telluride (MCT) has been directionally solidified for ten days in the Advanced Automated Directional Solidification Furnace (AADSF) on the second United States Microgravity Payload Mission (USMP-2). A second growth experiment is planned for the USMP-4 mission in November 1997. Results from USMP-2 demonstrated significant changes between microgravity and ground-based experiments, particularly in the compositional homogeneity. Changes were also observed during the microgravity mission which were dependent on the attitude of the space shuttle and the relative magnitudes of axial and transverse residual accelerations with respect to the growth axis of the crystal. Issues of shuttle operation, especially those concerned with safety and navigation, and the science needs of other payloads dictated the need for changes in attitude. One consequence for solidification of MCT in the USMP4 mission is the desire for a shorter growth time to complete the experiment without subjecting the sample to shuttle maneuvers. By using a seeded technique and a pre-processed boule of MCT with an established diffusion layer quenched into the solid, equilibrium steady state growth can be established within 24 hours, rather than the three days needed in USMP-2. The growth of MCT in AADSF during the USMP-4 mission has been planned to take less than 72 hours with 48 hours of actual growth time. A review of the USMP-2 results will be presented, and the rationale for the USMP-4 explained. Pre-mission ground based tests for the USN4P-4 mission will be presented, as will any available preliminary flight results from the mission.

  20. Current transport mechanisms in mercury cadmium telluride diode

    Science.gov (United States)

    Gopal, Vishnu; Li, Qing; He, Jiale; He, Kai; Lin, Chun; Hu, Weida

    2016-08-01

    This paper reports the results of modelling of the current-voltage characteristics (I-V) of a planar mid-wave Mercury Cadmium Telluride photodiode in a gate controlled diode experiment. It is reported that the diode exhibits nearly ideal I-V characteristics under the optimum surface potential leading to the minimal surface leakage current. Deviations from the optimum surface potential lead to non ideal I-V characteristics, indicating a strong relationship between the ideality factor of the diode with its surface leakage current. Diode's I-V characteristics have been modelled over a range of gate voltages from -9 V to -2 V. This range of gate voltages includes accumulation, flat band, and depletion and inversion conditions below the gate structure of the diode. It is shown that the I-V characteristics of the diode can be very well described by (i) thermal diffusion current, (ii) ohmic shunt current, (iii) photo-current due to background illumination, and (iv) excess current that grows by the process of avalanche multiplication in the gate voltage range from -3 V to -5 V that corresponds to the optimum surface potential. Outside the optimum gate voltage range, the origin of the excess current of the diode is associated with its high surface leakage currents. It is reported that the ohmic shunt current model applies to small surface leakage currents. The higher surface leakage currents exhibit a nonlinear shunt behaviour. It is also shown that the observed zero-bias dynamic resistance of the diode over the entire gate voltage range is the sum of ohmic shunt resistance and estimated zero-bias dynamic resistance of the diode from its thermal saturation current.

  1. Biomonitoring for iron, manganese, chromium, aluminum, nickel and cadmium in workers exposed to welding fume: a preliminary study

    Directory of Open Access Journals (Sweden)

    Mulyana

    2015-05-01

    Full Text Available The control of exposure to welding fumes is increasing importance in promoting a healthy, safe and productive work environment. This study is a case-control design, random study was conducted among welder (56 subjects and non welder (39 subjects with more than 1 years experience in the same job task in an automotive parts manufactory within the industrial area at Cikarang in 2013. All subjects were completed physical examination, informed consent and questionnaire. Blood heavy metals were determined by Inductively-Coupled Plasma Mass Spectrometry (ICP-MS. Whole blood iron, manganese, chromium and lead in welder were higher than non-welder, but not different for aluminum, nickel and cadmium. In welder, chromium and manganese correlated with smoking status, cadmium correlated with age and smoking status. In multivariate analysis, wholeblood cadmium correlates with age and smoking status.

  2. Wild Boar Tissue Levels of Cadmium, Lead and Mercury in Seven Regions of Continental Croatia

    Science.gov (United States)

    Sedak, Marija; Đokić, Maja; Šimić, Branimir

    2010-01-01

    Concentrations of cadmium, mercury and lead were analysed by atomic absorption spectrometry in the kidney and muscle of free-living wild boar (n = 169) from hunting grounds in seven counties of continental Croatia. Mean levels of metals (mg/kg) in muscle and kidney of boars ranged as follows: Cd: 0.005–0.016 and 0.866–4.58, Pb: 0.033–0.15 and 0.036–0.441, Hg: 0.004–0.012 and 0.04–0.152. In all seven regions, concentrations exceeded the permitted values (muscle and kidney mg/kg: cadmium 0.05/1; lead 0.1/0.5; mercury 0.03/0.1) in 13.6% and 71.6% of samples (muscle and kidney, respectively) for cadmium; 13.6% and 8.9% for lead; 19.5% and 2.4% for mercury. There were significant differences among the regions. Vukovar-Srijem and Virovitica-Podravina Counties were highly contaminated with cadmium, Sisak-Moslavina and Virovitica-Podravina Counties with lead and Brod-Posavina County had highest mercury concentrations. These results suggest a detailed investigation of physiological and environmental factors contributing to accumulation of metals in boars. PMID:20405101

  3. Mushroom contamination by mercury, cadmium and lead; Contaminazione di funghi commestibili con mercurio, cadmio e piombo

    Energy Technology Data Exchange (ETDEWEB)

    Dojmi Di Delupis, G.; Dojmi Di Delupis, F. [Istituto Superiore di Sanita`, Rome (Italy). Lab. di Tossicologia Comparata ed Ecotossicologia

    1996-12-01

    Occurrence and bioaccumulation of mercury, cadmium and lead were found in mushrooms by various researchers. Such mushrooms were often found in polluted areas. Pollution was mainly caused by industrial or mining plants, by some agricultural treatments and by road traffic. Considerations and recommendations concerning food consumption are made.

  4. Inhibition of aortic vessel adenosine diphosphate degradation by cadmium and mercury.

    Science.gov (United States)

    Togna, G; Dolci, N; Caprino, L

    1984-01-01

    The effects of cadmium and mercury on ADP breakdown by vessel walls were investigated. These metals reduce the ADP clearance promoted by arterial tissue. This effect could be attributed to the inhibition of vessel wall ADP-ase enzyme, which plays an important role in the genesis of thrombotic phenomena.

  5. Accumulation of mercury and cadmium in rice from paddy soil near a mercury mine.

    Science.gov (United States)

    Li, W C; Ouyang, Y; Ye, Z H

    2014-11-01

    Paddy soil and rice (Oryza sativa L.) in the Wanshan mining area in Guizhou Province, China, have been contaminated by toxic trace metals such as cadmium (Cd) and mercury (Hg). The present study examined correlations between the types and physicochemical parameters of the soil and the contents of trace metals and the different forms of Hg in rice. The health risks of consuming contaminated rice from the Wanshan mining area were also assessed. Sequential extraction procedures were used to investigate the chemical behavior of Hg in the soil. The results showed that Hg and Cd were the most abundant trace metals in the Wanshan mining area. The toxic methylmercury (MeHg) content was substantial in brown rice, and the total amounts of total Hg (THg), diethylenetriaminepentaacetic acid-Hg, and water-soluble Hg varied in the rhizosphere and non-rhizosphere soils. An antagonistic interaction between Mn in brown rice, straw, and husk and MeHg in brown rice was also shown. An analysis of calculated dietary intake, target hazard quotients, and hazard indexes showed a potential risk of transferring Hg, MeHg, and Cd to humans when rice from the Wanshan mining area is consumed. Therefore, it must be concluded that consuming contaminated rice near the Wanshan mining area is a potential threat to human health.

  6. Phytoaccumulation and phytotoxicity of cadmium and chromium in duckweed Wolffia globosa.

    Science.gov (United States)

    Boonyapookana, Benjaporn; Upatham, E Suchart; Kruatrachue, Maleeya; Pokethitiyook, Prayad; Singhakaew, Sombat

    2002-01-01

    The phytoaccumulation and phytotoxicity of heavy metals, cadmium (Cd), and chromium (Cr) on a common duckweed, Wolffia globosa, were studied. W. globosa were cultured in 3% Hoagland's nutrient medium, which was supplemented with 1, 2, 4, and 8 mg/L of Cd and Cr and were separately harvested after 3, 6, 9, and 12 days. The accumulation of Cd and Cr in W. globosa showed significant increases when the exposure time and metal concentration were increased. The effects of Cd and Cr on the biomass productivity and total chlorophyll content in W. globosa indicated that there were significant decreases in the biomass productivity and total chlorophyll content when the exposure time and metal concentration were increased.

  7. The effect of copper, zinc, mercury and cadmium on some sperm enzyme activities in the common carp (Cyprinus carpio L.).

    Science.gov (United States)

    Sarosiek, Beata; Pietrusewicz, Marta; Radziwoniuk, Julita; Glogowski, Jan

    2009-11-01

    The objective of the study was to determine the effect of copper, zinc, cadmium and mercury ions (100, 10 and 1 mg/l) on the activity of some enzymes of carp spermatozoa. Acid phosphatase activity was proved to be relatively insensitive to zinc ions, while copper, mercury and cadmium ions effectively inhibited the activity of this enzyme. Beta-N-acetylglucosaminidase activity was sensitive only to mercury ions. Lactic dehydrogenase activity remained unaffected by heavy metals. Our results showed that, among the examined metals, mercury had the strongest inhibitory effect on enzymatic activities.

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

    OpenAIRE

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

    2013-01-01

    Arsenic, cadmium, lead, and mercury present potential health risks to children who are exposed through inhalation or ingestion. Emerging Market countries experience rapid industrial development that may coincide with the increased release of these metals into the environment. A literature review was conducted for English language articles from the 21st century on pediatric exposures to arsenic, cadmium, lead, and mercury in the International Monetary Fund's (IMF) top 10 Emerging Market countr...

  9. Verkennend onderzoek naar inzetbaarheid van ED-XRF en ICPMS voor vaststelling van de gehalten aan lood, cadmium, chroom en kwik in verpakkingsmateriaal tbv de Regeling Verpakking en Verpakkingsafval

    NARCIS (Netherlands)

    Dijk J van; Beek A van de; Ritsema R; LAC

    2003-01-01

    Within the framework of the "Regulation of Packaging and Packaging Waste" are requirements for the amounts of cadmium, lead, mercury and chromium (CrVI). The sum of the amounts may not exceed the concentration of 100 ug/g. Because of analytical limitations chromium is determined as total chromium (C

  10. Optical property of amorphous semiconductor mercury cadmium telluride from first-principles study

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The structural and optical properties of amorphous semiconductor mercury cadmium telluride (a-MCT) are obtained by the first principles calculations. The total pair distribution functions and the density of states show that the a-MCT has the semiconductor characteristic. The calculated results of dielectric function show that E2 peak of the imaginary of dielectric function for the crystal mercury cadmium telluride abruptly disappears in the amorphous case due to the long-range disorders. And the imaginary of dielectric function of a-MCT shows a large broad peak, which is in agreement with the available results of other amorphous semiconductors. From the linear extrapolation of the curve ωε 2(ω)1/2 versus ω, it can be obtained that the optical energy gap of amorphous semiconductor Hg0.5Cd0.5Te is 0.51±0.05 eV.

  11. Detection of early kidney damages in workers exposed to lead, mercury, and cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Schaller, K.H.; Gonzales, J.; Thuerauf, J.; Schiele, R.

    1980-09-01

    Our study was performed to evaluate potential adverse effects on the kidney caused by an occupational exposure to cadmium, lead, and mercury, respectively. We examined 81 individuals of a Zn-Cd-plant and of a Ni-Cd-battery factory, occupationally exposed to cadmium. In a chemical company, synthesizing mercury-compounds, we analyzed 23 exposed workers. The 21 persons with an exposure to lead were employed in a secondary lead smelting plant. To evaluate the degree of the occupational exposure we analysed the concentrations of the heavy metals in blood and urine samples. As indicators of an adverse effect on the kidney the renal elimination of specific proteins was determined. The analysis of proteins with a higher molecular weight, such as albumine and acid ..cap alpha../sub 1/-glycoproteine, was performed using a new developed laser nephelometric method. Patterns of renal eliminated proteins with a lower molecular weight were characterized applying radio immunological determination of ..beta../sub 2/-microglobuline. The results found in workers exposed to cadmium verified previous studies. The occurence of a characteristic ..beta../sub 2/-microglobulinuria takes place after a sufficient long period of exposure. In addition to this,. cadmium exposed workers had an increased elimination of total proteine. Persons with an exposure to mercury also showed a slightly increased elimination of ..beta../sub 2/-microglobuline and total proteine. An intensive long exposure to mercury and its (in-)organic compounds seems to induce an increased renal elimination of proteins. No increased renal elimination was found in persons occupationally exposed to lead.

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

    Science.gov (United States)

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

    2017-03-02

    This study aimed to obtain insights into the presence of cadmium, lead, mercury and arsenic in feed materials and feed over time, for the purpose of guiding national monitoring. Data from the Dutch feed monitoring program and from representatives of the feed industry in the period 2007-2013 were used. Data covered the concentrations of cadmium, lead, mercury and arsenic in a variety of feed materials and compound feeds in The Netherlands. Trends in the percentage of samples that exceeded the maximum limit (ML), set by the European Commission, and trends in average, median and 90(th) percentile concentrations of each of these elements per feed material or compound feed were investigated. Based on the results, monitoring for cadmium, lead, mercury and arsenic should focus on feed material of mineral origin, feed material of marine origin, especially fish meal, seaweed and algae as well as feed additives belonging to the functional groups of (i) trace elements (notably cupric sulphate, zinc oxide and manganese oxide for arsenic) and (ii) binders and anti-caking agents. Mycotoxin binders are a new group of feed additives that also need attention. For complementary feed it is important to make a proper distinction between mineral and non-mineral feed because the ML in the latter group is usually lower. In seaweed/algae products a relatively large number of samples contained arsenic concentrations that exceeded the ML. Forage crops in general do not need high priority in monitoring programs, although for arsenic grass meal still needs attention.

  13. Lead, cadmium, arsenic and mercury in canned tuna fish marketed in Tehran, Iran.

    Science.gov (United States)

    Andayesh, Shirin; Hadiani, Mohammad Rasoul; Mousavi, Zahra; Shoeibi, Shahram

    2015-01-01

    Fifty-four canned tuna fish samples corresponding to 10 widely used different brands were purchased from local markets in Tehran, Iran during 2012-2013 and analysed on heavy metals. Mercury was determined by a direct mercury analyser without any sample preparation. For analysis of other elements samples were digested using a microwave apparatus. Lead and cadmium were determined by graphite furnace atomic absorption spectrometry and arsenic via hydride vapour generation. All samples had arsenic and mercury contamination. Arsenic levels showed a range of 0.25-1.42 mg kg(-1), which might be due to lack of national and international limits for arsenic in canned tuna fish. Lead and cadmium were measured in a small number of samples with a mean of 0.053 ± 0.058 mg kg(-1) and 0.013 ± 0.015 mg kg(-1), respectively. Results obtained for these heavy metals in all samples were lower than the corresponding limits, whereas arsenic and mercury contents might raise some attention.

  14. Magnetite nanoparticle (NP) uptake by wheat plants and its effect on cadmium and chromium toxicological behavior.

    Science.gov (United States)

    López-Luna, J; Silva-Silva, M J; Martinez-Vargas, S; Mijangos-Ricardez, O F; González-Chávez, M C; Solís-Domínguez, F A; Cuevas-Díaz, M C

    2016-09-15

    The aim of this work was to assess the uptake of citrate-coated magnetite nanoparticles (NPs) by wheat plants and its effect on the bioaccumulation and toxicity of individual and joint Cd(2+) and Cr(6+) levels. Seven-day assays were conducted using quartz sand as the plant growth substrate. The endpoints measured were seed germination, root and shoot lengths, and heavy metal accumulation. Magnetite exhibited very low toxicity, regardless of the wheat seedling NP uptake and distribution into roots and shoots. The seed germination and shoot length were not sensitive enough, while the root length was a more sensitive toxicity endpoint. The root length of wheat seedlings exposed to individual metals decreased by 50% at 2.67mgCd(2)(+)kg(-1) and 5.53mgCr(6+)kg(-1). However, when magnetite NPs (1000mgkg(-1)) were added, the root length of the plants increased by 25 and 50%. Cd(2+) and Cr(6+) showed similar and noninteractive joint action, but strongly impaired the wheat seedlings. In contrast, an interactive infra-additive or antagonistic effect was observed upon adding magnetite NPs. Thus, cadmium and chromium accumulation in vegetable tissues was considerately diminished and the toxicity alleviated.

  15. Cadmium, Chromium, and Copper Concentration plus Semen-Quality in Environmental Pollution Site, China

    Science.gov (United States)

    LI, Yan; GAO, Qiaoyan; LI, Mingcai; LI, Mengyang; GAO, Xueming

    2014-01-01

    Abstract Background The environmental pollution is one of the factors contributing to the decrease of sperm quality for human beings. The aim of this study was to assess cadmium (Cd), chromium (Cr), and copper (Cu) concentration of man in environmental pollution site, and explore relationships between men exposure to Cd, Cr, and Cu and semen-quality parameters in environmental pollution site. Methods Ninety five men were recruited through pollution area and controls in 2011. We measured semen quality using Computer-aided Semen Quality Analysis, and Cd, Cr, and Cu levels in seminal plasma using Graphite Gurnace Atomic Absorption Spectroscopy. Spearman rank correlation analysis was used to evaluate the correlation between Cd, Cr and Cu concentration in seminal plasma and semen quality. Results The mean of seminal plasma Cd, Cr, and Cu values in pollution area was higher than the controls. Seminal plasma Cr values displayed a significant negative correlation with total motility and normomorph sperm rate. Seminal plasma Cu values also displayed a negative correlation with normomorph sperm rate. Conclusions Male reproductive health may be threatened by environmental pollution, and it may be influence local population diathesis. PMID:26060677

  16. Absorption Reduction Capacity with Chromium (Cr and Cadmium (Cd Contaminants of Vetiver Phytoremediation Process on Compost Soil

    Directory of Open Access Journals (Sweden)

    Ahamad Zubair

    2016-01-01

    Full Text Available This study aims to analyze the large of reduction capacity of chromium metals and cadmium in the soil compost media and absorption capacity of chrome and cadmium in phytoremediation process of vetiver; to compare the reduction-absorption capacities of chromium and cadmium metals in phytoremediation process of vetiver (Vetivera zizanioides. The study was carried out for 2 months with a range of sampling every 7 days, and then analyzed by using Atomic Absorption Spectrophotometer (AAS. Contaminants used as artificial contaminants containing heavy metals chromium (Cr and cadmium (Cd. This study is an experimental research includes two variables. First, the variations of Cr concentrations used were 400 ppm, 600 ppm and 800 ppm and Cd concentrations used were 40 ppm, 60 ppm, 800 ppm. Secondly, the variations of total plant are 3, 6, and 9 plant. The period of observation is made every week. Planting media used is compost soil with compost and clay composition of 20%, 30% and 40%. The results of study showed that there are a significant relationship between the reduction capacity of Cr and Cd of compost soil and the absorption capacity of Cr and Cd for vetiver (Vetiveria zizanioides. The higher of Cr and Cd decreases in soil followed by increased levels of Cr and Cd in vetiver (Vetiveria zizanioides. The capacity of Cr reduction varies between 57% - 86% and Cd 36% - 64% where as the absorption capacity of vetiver on Cr between 38% - 75% and Cd between 34%-74%. The capacity of reduction-absorption of Cr is relatively higher than Cd in phytoremediation process of vetiver.

  17. Exposure of rainbow trout milt to mercury and cadmium alters sperm motility parameters and reproductive success

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, Grzegorz J., E-mail: dietrich@pan.olsztyn.pl [Department of Gamete and Embryo Biology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Tuwima 10, 10-747 Olsztyn (Poland); Dietrich, Mariola; Kowalski, R.K. [Department of Gamete and Embryo Biology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Tuwima 10, 10-747 Olsztyn (Poland); Dobosz, Stefan [Department of Salmonid Research, Inland Fisheries Institute, Rutki 83-330 Zukowo (Poland); Karol, Halina; Demianowicz, Wieslaw; Glogowski, Jan [Department of Gamete and Embryo Biology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Tuwima 10, 10-747 Olsztyn (Poland)

    2010-05-10

    In the current work, seminal plasma was used for the first time as an incubation medium for monitoring short-time exposure effects of sublethal concentrations of mercury and cadmium ions on rainbow trout sperm. Sperm motility parameters (CASA) and hatching rates were used as gamete quality markers. Additionally live/dead sperm viability test and comet assay of DNA fragmentation were performed. We demonstrated that computer-assisted sperm motility analysis (CASA) may serve as a predictor of reproductive success, when milt contaminated with heavy metals is used. Results presented in this study demonstrate that mercury ions altered sperm motility characteristics at 1-10 mg Hg{sup 2+}/l and 10 mg Cd{sup 2+}/l and hatching rates at 10 mg Hg{sup 2+}/l and 10 mg Cd{sup 2+}/l after 4 h of exposure. Although mercury ions affected sperm motility parameters immediately after dilution with milt as well as at 4 h of exposure, no differences in sperm motility parameters were found between intact and mercury-treated milt after 24 h of exposure. Our results suggest that rainbow trout seminal plasma has a protective role against the toxic effects of mercury ions of rainbow trout sperm motility.

  18. HEAVY METALS ABUNDANCE IN THE SOILS OF THE PANTELIMON – BRĂNEŞTI AREA, ILFOV COUNTY a CADMIUM, COBALT, CHROMIUM, COPPER

    Directory of Open Access Journals (Sweden)

    Radu Lacatusu

    2011-12-01

    Full Text Available More than 20 years later, a new research on heavy metals (cadmium, cobalt, chromium, copper contents in the soil cover of the Pantelimon – Brăneşti area located East of the Bucharest Municipality and exposed for several decades to the influence of industrial emissions from two non-ferrous metallurgy plants is presented. A 5,912.72 ha area was investigated, 544 samples taken by geometric horizons (0-20; 20-40; 40-60 cm from 215 points have been analyzed.The dominant soils are: Preluvosols, Chernozems, Phaeozems. The analytical data showed that all the heavy metals contents are below the maximum allowable limits and of the alarm thresholds. Higher cadmium and copper concentrations have been registered in the 40-60 cm layer and higher chromium and copper concentrations in the 0-20 cm layer. Cadmium and cobalt distributions are non-central, with a right asymmetry, and the chromium and copper ones are slightly symmetric. The surface distribution of the heavy metals shows the presence of some high contents areas distributed insularly, with a higher frequency around the industrial units. The geochemical abundance indexes are higher than 1 for cadmium and lower for cobalt, chromium, and copper, and the pedo-geochemical abundance indexes are lower than 1 only for chromium.

  19. Cadmium, iron, lead and mercury bioaccumulation in abu mullet, Liza abu, different tissues from Karoun and Karkheh rivers, Khozestan, Iran.

    Science.gov (United States)

    Askary Sary, Abolfazl; Beheshti, Mahboubeh

    2012-02-01

    Lead, mercury, cadmium and iron concentration in following tissues: muscle, liver and gill of Liza abu in Karoun and Kharkheh were measured. Karoun and Kharkheh are important rivers in Iran. Significant variation in metal values were evaluated using Student's t test at p < 0.05. Result showed that maximum concentration of metals were recorded in gill tissues. Iron concentration was higher than lead, cadmium and mercury in different organs (p < 0.05). The level of metals Cd, Hg, Fe in different tissues of Karoun river was higher than Karkheh river (p < 0.05). Metals level in different tissue were upper than WHO standard.

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

    Science.gov (United States)

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

    2014-09-29

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

  1. DDE, PCBs, cadmium, lead, and mercury concentrations in rhinoceros auklets from Washington

    Science.gov (United States)

    Blus, L.J.; Fitzner, R.E.; Leschner, L.L.; Wilson, U.W.

    1999-01-01

    In July 1981, 5 adult rhinoceros auklets (Cerorhinca monocerata) were captured on the ground near nesting areas on each of Protection and Destruction Islands, Washington. The birds were euthanized, and their livers and kidneys removed and analyzed. Levels (I?g / g wet weight) of DDE (0.11 to 0.95), polychlorinated biphenyls (no residue detected [ND] to 1.1), mercury (0.60 to 1.8), and lead (ND to 0.85) in livers and cadmium (9.1 to 21.9) in kidneys were similar in each colony. All concentrations were less than known effect levels.

  2. Thermal and Mechanical Properties of a Complex Nonlinear Optical Material: Cadmium Mercury Thiocyanate Crystal

    Institute of Scientific and Technical Information of China (English)

    YUAN Duo-Rong; XU Dong; ZHANG Guang-Hui; LIU Ming-Guo; GUO Shi-Yi; MENG Fan-Qing; LU Meng-Kai; FANG Qi; JIANG Min-Hua

    2000-01-01

    Institute of Crystal Materials and State Key Laboratory of Crystal Materials, Shandong University, Ji'nan 250100 (Received 18 March 2000) The data of the thermal expansion and specific heat of cadmium mercury thiocyanate crystal have been obtained. The specific heat is 0.7588J/g℃ at room temperature. The thermal expansion occurs in the direction parallel to the c-axis, and the thermal contraction occurs in the direction parallel to the a-axis. The thermal expansion is the same as the thermal contraction at 353 K. The relationship between thermal properties and crystal structure is discussed.

  3. Chromium

    Science.gov (United States)

    ... Intern Med 1991;115:917-24. Abraham AS, Brooks BA, Eylath U. The effects of chromium supplementation on serum glucose and lipids in patients with and without non-insulin-dependent diabetes. Metabolism 1992;41:768-71. Hermann J, Arquitt A. ...

  4. Lead, cadmium and mercury contents and bioaccumulation potential of wild edible saprophytic and ectomycorrhizal mushrooms, Croatia.

    Science.gov (United States)

    Širić, Ivan; Kasap, Ante; Bedeković, Dalibor; Falandysz, Jerzy

    2017-03-04

    Lead (Pb), cadmium (Cd), and mercury (Hg) contents in ten species of edible mushrooms in Trakošćan, Croatia were determined. In addition, the similarity between the studied species was determined by cluster analysis. The caps and stipes of the fruiting bodies were analysed separately. The analyses were carried out by inductively coupled plasma - optical emission spectrometry (ICP-OES). The greatest mean lead concentrations of 1.91 and 1.60 mg kg (-1) were determined in caps and stipes of Macrolepiota procera. The greatest mean concentrations of cadmium (3.23 and 2.24 mg kg(-1)) were determined in caps and stipes of Agaricus campestris and of mercury (2.56 and 2.35 mg kg(-1)) in Boletus edulis. In terms of the anatomical parts of the fruiting body (cap-stipe), a considerably greater concentration of the analysed elements was found in the cap for all mushroom species. According to calculated bio-concentration factors, all the examined species were found to be bio-accumulators of Cd and Hg. On the basis of the accumulation of the studied metals, great similarity of mushroom species belonging to the same genus and partial similarity of species of the same ecological affiliation was obtained by cluster analysis.

  5. Comparison of pollutant emission control strategies for cadmium and mercury in urban water systems using substance flow analysis

    DEFF Research Database (Denmark)

    Revitt, D. M.; Lundy, L.; Eriksson, Eva

    2013-01-01

    for the evaluation of ECS using substance flow analysis (SFA). The results indicate that the full implementation of existing EU legislation is capable of reducing the total emissions of cadmium (Cd) and mercury (Hg) by between 11% and 20%. The ability to apply voluntary reduction practices is shown...

  6. [Levels of lead, cadmium and mercury in the hair of inhabitants of the Nantes and Grenoble areas].

    Science.gov (United States)

    Boiteau, H L; Stoklov, M; Remond, D; Buffet, H; Metayer, C; Vincent, F; Corneteau, H; Faure, J

    1983-11-01

    Lead, cadmium and mercury were measured in the air of 398 inhabitants of the Grenoble area and 341 inhabitants of the Nantes area. The hair was washed with hor solution of EDTA, dissolved in nitric acid and analyzed by electrothermal atomic absorption spectrometry. The average concentrations are 6,23 micrograms/g for lead, 0,40 microgram/g for cadmium and 1,06 microgram/g for mercury. There is no difference between found data of the two areas for lead and cadmium. Mercury levels are higher in the Nantes area. Lead content is higher in male hair than in female hair, but the difference is not significant. In the Grenoble area, mercury levels are higher in males than in females; the process is reversed in the Nantes area. We have found no relation between metal levels and age of persons, but lead content is high in the hair of people under ten. Artisans and mechanics have lead content higher than the general people, though exposed people to occupational risks is excluded. We have found to relation between metal in the hair and the size of the town. It seems that the use of tobacco is without influence. Mercury content is related to the eating of fish. It is not increased in the population because of dental amalgams.

  7. Evaluation and Determination of Heavy Metals (Mercury, Lead and Cadmium in Human Breast Milk

    Directory of Open Access Journals (Sweden)

    Abdollahi Atousa

    2014-07-01

    Full Text Available Mercury, Lead and Cadmium were determined in 100 samples of human breast milk samples from urban and rural mothers in Isfahan (IRAN. A questionnaire about area of residence, nutrition, smoking habits, and dental fillings was filled out by the lactating mothers. The combination of nitric acid, hydrogen peroxide and perchloric acid was found to be one of the most suitable acids in wet digestion of milk. Cold vapor atomic absorption was used to determine the mercury content in milk after wet digestion. The effect of concentration of nitric acid, influence of flow rate and tin(П chloride were investigated. The mean concentration of mercury in human breast milk samples was 0.96 ppb. Extraction of Pb and Cd were performed with ammonium pyrrolidine dithiocarbamate (APDC to methyl isobutyl ketone (MIBK and were determined by Flame Atomic Absorption Spectrometry. The factors influencing, the complex formation, pH, time and buffer were optimized. The mean concentration of Pb and Cd in human breast milk was 0.0147 and 0.0121 ppm, respectively. The maximum concentrations were found in breast milk of rural mothers.

  8. Effects of environmental levels of cadmium, lead and mercury on human renal function evaluated by structural equation modeling.

    Science.gov (United States)

    Trzeciakowski, Jerome P; Gardiner, Lesley; Parrish, Alan R

    2014-07-03

    A relationship between exposure to heavy metals, including lead and cadmium, and renal dysfunction has long been suggested. However, modeling of the potential additive, or synergistic, impact of metals on renal dysfunction has proven to be challenging. In these studies, we used structural equation modeling (SEM), to investigate the relationship between heavy metal burden (serum and urine levels of lead, cadmium and mercury) and renal function using data from the NHANES database. We were able to generate a model with goodness of fit indices consistent with a well-fitting model. This model demonstrated that lead and cadmium had a negative relationship with renal function, while mercury did not contribute to renal dysfunction. Interestingly, a linear relationship between lead and loss of renal function was observed, while the maximal impact of cadmium occurred at or above serum cadmium levels of 0.8 μg/L. The interaction of lead and cadmium in loss of renal function was also observed in the model. These data highlight the use of SEM to model interaction between environmental contaminants and pathophysiology, which has important implications in mechanistic and regulatory toxicology.

  9. Associations of neonatal lead, cadmium, chromium and nickel co-exposure with DNA oxidative damage in an electronic waste recycling town

    Energy Technology Data Exchange (ETDEWEB)

    Ni, Wenqing; Huang, Yue; Wang, Xiaoling; Zhang, Jingwen; Wu, Kusheng, E-mail: kswu@stu.edu.cn

    2014-02-01

    Objective: This study aimed to evaluate the effects of toxic heavy metal co-exposure on DNA oxidative damage in neonates from a primitive e-waste recycling region, Guiyu town, China. Methods: Our participants included 201 pregnant women: 126 from Guiyu town and 75 from Jinping district of Shantou city, where no e-waste recycling and dismantling activities existed. Structured interview questionnaires were administered to the pregnant women and umbilical cord blood (UCB) samples were collected after delivery. The UCB concentrations of lead, cadmium, chromium, and nickel were analyzed by graphite furnace atomic absorption spectrometry (GFAAS). Levels of UCB plasma 8-hydroxydeoxyguanosine (8-OHdG, a DNA oxidative damage biomarker) were determined by enzyme-linked immunosorbent assay. Results: Our results suggested that UCB lead and cadmium concentrations in neonates of Guiyu were significantly higher than those of Jinping (lead: median 110.45 ng/mL vs. 57.31 ng/mL; cadmium: median 2.50 ng/mL vs. 0.33 ng/mL, both P < 0.001). Parents' residence in Guiyu, and parents' work related to e-waste recycling were the risk factors associated with neonate's UCB lead and cadmium levels. No significant difference of UCB plasma 8-OHdG levels was found between Guiyu and the control area. After adjusting for potential confounders, cord plasma 8-OHdG concentrations (ng/mL) were positively associated with blood cadmium (β = 0.126 ng/mL, 95% CI: 0.055 to 0.198 ng/mL), chromium (β = 0.086 ng/mL, 95% CI: 0.014 to 0.158 ng/mL) and nickel (β = 0.215 ng/mL, 95% CI: 0.113 to 0.317 ng/mL) concentrations. Conclusions: The primitive e-waste recycling and dismantling activities may contribute to the elevated umbilical cord blood toxic heavy metal levels in neonates born in Guiyu. Exposures to cadmium, chromium and nickel were associated with increased oxidative DNA damage in neonates. - Highlights: • DNA oxidative damage levels (8-OHdG) in neonates from Guiyu were assessed.

  10. Determination of chromium, cadmium and manganese in water and fish samples after preconcentration using penicillium digitatum immobilized on pumice Stone

    Energy Technology Data Exchange (ETDEWEB)

    Baytak, Sitki [Nevsehir University, Science and Art Faculty, Chemistry Department, Nevsehir (Turkey); Tuerker, A.R. [Gazi University, Science and Art Faculty, Chemistry Department, Ankara (Turkey)

    2009-04-15

    This study presents a procedure for preconcentration of Cr(III), Cd(II) and Mn(II) from water and biological samples using Penicillium digitatum immobilized on pumice stone. Optimum conditions such as pH, flow rate were evaluated. The recoveries of Cr(III), Cd(II) and Mn(II) under optimum conditions were found to be 98{+-}2%, 100{+-}2%, and 97{+-}2%, respectively, at a 95% confidence level. Detection limits were 2.0, 1.6 and 1.5 ng/mL for Cr(III), Cd(II) and Mn(II), respectively. The proposed procedure was successfully applied for the determination of chromium, cadmium and manganese in dam water, spring water and fish (Carp) samples. The accuracy was evaluated through the analysis of the certified standard reference fish tissue samples (IAEA-407) and spiked fish and water samples. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  11. Occurrence of high levels of cadmium, mercury and lead in medicinal plants of India

    Directory of Open Access Journals (Sweden)

    Deepa T Vasudevan

    2009-01-01

    Plants can contain heavy metals from their presence in the soil, water or air. High levels of toxic metals can occur when the plants are grown in polluted areas, such as near roadways or metal mining and smelting operations. In addition, high levels can be found when agricultural expedients are used, including Cadmium containing fertilizers, organic mercury or lead based pesticides, and contaminated irrigation water. Quality has to be built into the whole process beginning from the selection of starting material to the final product reaching the consumer. In the present study were carried out, to evaluate the quality and safety of crude drug. The result shows that Indian herbal drug industry needs to ensure procurement of standardized authentic raw material free from toxic contaminants. Such approaches remain important in global promotion of medicinal plants & herbal medicinal products from India.

  12. Studies of cadmium, mercury and lead in man. The value of X-ray fluorescence measurements in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Boerjesson, J.

    1996-10-01

    Two XRF methods have been used for in vivo studies of mercury, cadmium and lead. Persons with a history of long-term occupational mercury exposure had elevated mercury concentrations in their kidneys (up to 65 {mu}g/g). The minimum detectable concentration varied between 12 and 45 {mu}g/g. Battery plant workers had elevated cadmium concentrations in their kidneys (up to 350 {mu}g/g) and liver (up to 80 {mu}g/g), with mean values about 3-5 times higher than the general population. The mean ratio between concentrations of cadmium in kidney and liver was 7. Levels in kidney and liver indicated that a simple integration of cadmium in work-place air is not sufficient to describe the body burden. Fingerbone lead in smelters was 6-8 times higher than in members of the general population. The half-time of bone lead in active workers was estimated to about 5 years during the accumulation phase. A model for description of a person`s lead exposure in terms of lead in fingerbone, lead in blood and time of exposure has been developed and can be used, e.g. for retrospective blood lead estimates if the period of exposure and the current fingerbone lead is known. This will be of value for the evaluation of toxic effects of long-term lead exposure when data on previous lead levels are lacking. In total, in vivo measurements of mercury, cadmium and lead give unique information, which has shown to be an important tool for understanding of metal kinetics and toxicity. If the precision and accuracy of the method can be further improved, the technique will also have a given place in the clinical practice. 168 refs, 9 figs, 3 tabs

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

    Energy Technology Data Exchange (ETDEWEB)

    Barregard, Lars, E-mail: lars.barregard@amm.gu.se [Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital and University of Gothenburg, P.O. Box 414, SE 405 30 Gothenburg (Sweden); Fabricius-Lagging, Elisabeth [Department of Nephrology, Sahlgrenska University Hospital and Boras Hospital (Sweden); Lundh, Thomas [Department of Occupational and Environmental Medicine, Lund University Hospital and Lund University (Sweden); Moelne, Johan [Department of Clinical Pathology, Sahlgrenska University Hospital and University of Gothenburg (Sweden); Wallin, Maria [Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital and University of Gothenburg, P.O. Box 414, SE 405 30 Gothenburg (Sweden); Olausson, Michael [Department of Transplantation and Liver Surgery, Sahlgrenska University Hospital and University of Gothenburg (Sweden); Modigh, Cecilia; Sallsten, Gerd [Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital and University of Gothenburg, P.O. Box 414, SE 405 30 Gothenburg (Sweden)

    2010-01-15

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

  14. Cadmium and mercury cause an oxidative stress-induced endothelial dysfunction.

    Science.gov (United States)

    Wolf, Matthew B; Baynes, John W

    2007-02-01

    We investigated the ability of cadmium and mercury ions to cause endothelial dysfunction in bovine pulmonary artery endothelial cell monolayers. Exposure of monolayers for 48 h to metal concentrations greater than 3-5 microM produced profound cytotoxicity (increased lactate dehydrogenase leakage), a permeability barrier failure, depletion of glutathione and ATP and almost complete inhibition of the activity of key thiol enzymes, glucose-6-phosphate dehydrogenase (G6PDH) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). In contrast, metal concentrations less than 1-2 microM induced increases in glutathione and thiol-enzyme activities with minimal changes in LDH leakage, barrier function and ATP content. At shorter incubation times (24 h or less), high concentrations of cadmium caused glutathione induction rather than depletion. Thus, oxidative stress and cytotoxicity induced by lower concentrations of the metal ions stimulate compensatory responses, including increased synthesis of glutathione, which presumably preserved the activity of key thiol enzymes, however these responses were not sustainable at higher metal ion concentrations. We conclude, while high concentrations of heavy metals are cytotoxic, lower concentration induce a compensatory protective response, which may explain threshold effects in metal-ion toxicity.

  15. Hair mercury and urinary cadmium levels in Belgian children and their mothers within the framework of the COPHES/DEMOCOPHES projects

    Energy Technology Data Exchange (ETDEWEB)

    Pirard, Catherine, E-mail: c.pirard@chu.ulg.ac.be [CHU of Liege, Laboratory of Clinical, Forensic and Environmental Toxicology, CHU (B35), 4000 Liege (Belgium); Koppen, Gudrun, E-mail: gudrun.koppen@vito.be [Flemish Institute of Technological Research, Environmental Risk and Health Unit, Boeretang 200, 2400 Mol (Belgium); De Cremer, Koen, E-mail: Koen.DeCremer@wiv-isp.be [Scientific Institute of Public Health, Juliette Wytsmanstraat 14, 1050 Brussels (Belgium); Van Overmeire, Ilse, E-mail: ilse.vanovermeire@wiv-isp.be [Scientific Institute of Public Health, Juliette Wytsmanstraat 14, 1050 Brussels (Belgium); Govarts, Eva, E-mail: eva.govarts@vito.be [Flemish Institute of Technological Research, Environmental Risk and Health Unit, Boeretang 200, 2400 Mol (Belgium); Dewolf, Marie-Christine, E-mail: marie_christine.dewolf@hainaut.be [Provincial Institute Hainaut Vigilance Sanitaire — Hainaut Hygiène Publique en (HVS-HPH), Boulevard Sainctelette, 55, 7000 Mons (Belgium); Van De Mieroop, Els, E-mail: Els.VanDeMieroop@pih.provant.be [Provincial Institute for Hygiene (PIH), Boomgaardstraat 22 bus 1, 2600 Antwerpen (Belgium); Aerts, Dominique, E-mail: dominique.aerts@milieu.belgie.be [Federal Public Service Health, Food Chain Safety and Environment, Place Victor Horta 40/10, 1060 Brussels (Belgium); Biot, Pierre, E-mail: pierre.biot@environnement.belgique.be [Federal Public Service Health, Food Chain Safety and Environment, Place Victor Horta 40/10, 1060 Brussels (Belgium); Casteleyn, Ludwine, E-mail: Ludwine.Casteleyn@med.kuleuven.be [University of Leuven, Center for Human Genetics, Herestraat 49, 3000 Leuven (Belgium); Kolossa-Gehring, Marike, E-mail: marike.kolossa@uba.de [Federal Environment Agency, Corrensplatz 1, 14195 Berlin (Germany); Schwedler, Gerda, E-mail: Gerda.Schwedler@uba.de [Federal Environment Agency, Corrensplatz 1, 14195 Berlin (Germany); and others

    2014-02-01

    A harmonized human biomonitoring pilot study was set up within the frame of the European projects DEMOCOPHES and COPHES. In 17 European countries, biomarkers of some environmental pollutants, including urinary cadmium and hair mercury, were measured in children and their mothers in order to obtain European-wide comparison values on these chemicals. The Belgian participant population consisted in 129 school children (6–11 years) and their mothers (≤ 45 years) living in urban or rural areas of Belgium. The geometric mean levels for mercury in hair were 0.383 μg/g and 0.204 μg/g for respectively mothers and children. Cadmium in mother's and children's urine was detected at a geometric mean concentration of respectively 0.21 and 0.04 μg/l. For both biomarkers, levels measured in the mothers and their child were correlated. While the urinary cadmium levels increased with age, no trend was found for hair mercury content, except the fact that mothers hold higher levels than children. The hair mercury content increased significantly with the number of dental amalgam fillings, explaining partially the higher levels in the mothers by their higher presence rate of these amalgams compared to children. Fish or seafood consumption was the other main parameter determining the mercury levels in hair. No relationship was found between smoking status and cadmium or mercury levels, but the studied population included very few smokers. Urinary cadmium levels were higher in both mothers and children living in urban areas, while for mercury this difference was only significant for children. Our small population showed urinary cadmium and hair mercury levels lower than the health based guidelines suggested by the WHO or the JECFA (Joint FAO/WHO Expert Committee on Food Additives). Only 1% had cadmium level slightly higher than the German HBM-I value (1 μg/l for adults), and 9% exceeded the 1 μg mercury/g hair suggested by the US EPA. - Highlights: • Hair mercury and

  16. Contamination by mercury and cadmium in the cetacean products from Japanese market.

    Science.gov (United States)

    Endo, T; Haraguchi, K; Cipriano, F; Simmonds, M P; Hotta, Y; Sakata, M

    2004-03-01

    Cetaceans hunted coastally in Japan include several species of odontocete (dolphins, porpoises and beaked whales), and fresh and frozen red meat and blubber, as well as boiled internal organs, such as liver, lung, kidney and small intestine, are still sold for human consumption. Furthermore, red meat and blubber products originating from mysticete minke whales caught in the Antarctic and Northern Pacific are also sold for human consumption. We surveyed mercury and cadmium contamination levels in boiled liver, lung, kidney and red meat products being marketed in Japanese retail outlets. We also analyzed the DNA of these products to obtain information concerning gender and species. Total mercury (T-Hg) and methyl mercury (M-Hg) contamination levels in all the cetacean products were markedly higher in odontocete species than in mysticete species, and slightly higher in females than in males. T-Hg contamination in the organs was seen in the following order: boiled liver>boiled kidney=boiled lung>red meat. In particular, T-Hg concentrations in the boiled liver were high enough to cause acute intoxication even from a single ingestion: the mean +/-SD (range) of T-Hg was 388+/-543 (0.12-1980) microg/wetg. In contrast, although M-Hg contamination in the liver was not markedly higher than that in other organs, M-Hg contamination was in the following order: boiled liver>odontocete red meat>boiled kidney>boiled lung. The contamination levels of T-Hg and M-Hg in odontocete red meat, the most popular whale product, were 8.94+/-13.3 and 5.44+/-5.72 microg/wetg, respectively. These averages exceeded the provisional permitted levels of T-Hg (0.4 microg/wetg) and M-Hg (0.3 microg/wetg) in marine foods set by the Japanese Ministry of Health, Labor and Welfare by 22 and 18 times, respectively, suggesting the possibility of chronic intoxication by T-Hg and M-Hg with frequent consumption of odontocete red meat. Cadmium contamination levels in boiled liver, kidney and lung were 8

  17. Determination of forbidden and restricted elements lead, cadmium, arsenic, mercury, antimony, chromium, nickel, barium and strontium in cosmetic products by ICP-AES%ICP-AES法测定化妆品中铅、镉、砷、汞、锑、铬、镍、钡、锶等禁限用元素含量

    Institute of Scientific and Technical Information of China (English)

    戴骐; 林晓娜; 吴艳燕; 楼士铭; 陈俊晓

    2012-01-01

    建立了化妆品中铅(Pb)、镉(Cd)、砷(As)、汞(Hg)、锑(Sb)、铬(Cr)、镍(Ni)、钡(Ba)、锶(Sr)含量的电感耦合等离子体原子发射光谱法(ICP-AES)同步检测技术.采用微波消解,在较难消化的化妆品中加HF进行消化,铑(Rh)为内标元素消除基体干扰,以配备耐HF进样系统的ICP-AES进行测定.在0~1.0 mg/L 范围内呈现良好的线性关系(相关系数≥0.9999),Pb、Cd、As、Hg、Sb、Cr、Ni、Ba、Sr 检出限分别为0.0016,0.0007,0.0021,0.0013,0.0003,0.0009,0.0008,0.0009,0.0021 mg/L,方法回收率80.2%~111%,精密度1.7%~8.2%.结果表明,该方法适用于检测基体复杂的化妆品中Pb、Cd、As、Hg、Sb、Cr、Ni、Ba、Sr.%A method for the determination of the forbidden and restricted elements lead(Pb), cadmium (Cd), arsenic (As), mercur(Hg), antimony (Sb), Chroium(Cr), Nickel (Ni) , barium (Ba)and strontiume (Sr) in cosmetic products by inductively coupled plasma mass spectrometry( ICP-AES) was developed. The sample was microwave digested with HNO3 H2O2 and HF, then detected by ICP-AES. This method achieves practical quantitation limits for the 9 elements of 0.0016,0.0007,0.0021,0.0013,0.0003,0. 0009,0.0008,0.0009, 0. 0021 mg/L, respectively. The correlation coefficients of calibration curves in the range of 0 to 1.0 mg/L were more than 0. 9999. The recoveries and precision of the method were 80. 2% -111% and 1. 7% ~ 8. 2%. This level of measurement allows for the accurate assessment of 9 forbidden and restricted elements in cosmetic food.

  18. Arsenic, cadmium, and mercury in cocoyam (Xanthosoma sagititolium) and watercocoyam (Colocasia esculenta) in Tarkwa a mining community.

    Science.gov (United States)

    Essumang, D K; Dodoo, D K; Obiri, S; Yaney, J Y

    2007-10-01

    Cocoyam (Xanthosoma sagititolium) and Watercocoyam (Colocasia esculenta) have gained increased importance in the diets of majority of people in developing countries such as Ghana. The concentration levels of arsenic, cadmium, and mercury in Cocoyam (X. sagititolium) and Watercocoyam (C. esculenta) in Tarkwa and its surrounding villages a mining community in Ghana were measured in this study. From the results of the study, the levels of arsenic, cadmium and mercury in X. sagititolium and C. esculenta were higher than the WHO recommended levels. These root tubers absorb or uptake toxic chemicals from the soil as a result of the mining operations. This means that, the consumption of X. sagititolium and C. esculenta by humans from such environments may pose a serious health risk. There is therefore the need for a concerted effort by all to minimize the negative impact of gold mining in the study area.

  19. Replacement for Cadmium Plating and Hexavalent Chromium on Fasteners and Electrical Connectors

    Science.gov (United States)

    2010-02-10

    or iron • Aluminum alloy 2024 • Cadmium • Aluminum alloy 1100 • Aluminum (high purity) • Zinc • Magnesium and magnesium alloys Active / Anodic...Cladding of structural aluminum and steel parts – Aluminized mufflers • Aircraft – Skin cladding – High strength landing gear (No hydrogen

  20. Exposure to heavy metals (lead, cadmium and mercury) and its effect on the outcome of in-vitro fertilization treatment.

    Science.gov (United States)

    Al-Saleh, Iman; Coskun, Serdar; Mashhour, Abdullah; Shinwari, Neptune; El-Doush, Inaam; Billedo, Grisellhi; Jaroudi, Kamal; Al-Shahrani, Abdulaziz; Al-Kabra, Maya; El Din Mohamed, Gamal

    2008-10-01

    We investigated the effect of lead, cadmium and mercury exposure on pregnancy and fertilization rate outcome among 619 Saudi women (age 19-50 years) who sought in-vitro fertilization (IVF) treatment between 2002 and 2003. The concentrations of lead, cadmium and mercury were measured in both blood and follicular fluids. At levels well below the current US occupational exposure limit guidelines (40microg/dL) and even less than the current Centers for Disease Control and Prevention level of concern for preventing lead poisoning in children (10microg/dL), blood lead level was negatively associated with fertilization outcome in both adjusted and unadjusted logistic regression models. We found that among various demographic, socioeconomic and environmental factors, fish consumption was positively associated with blood lead levels. These results support the hypothesis that a raised blood lead level affects infertility and intervention to reduce the lead exposure might be needed for women of reproductive age. The present results also revealed unexpected finding - the positive relationship between follicular cadmium levels and fertilization outcome, which points to the necessity for further investigation. Though adverse effect of mercury on pregnancy outcome or fertilization rate was not evident in this study, mercury5.8microg/L (EPA safety limit) was found in the blood and follicular fluid of 18.7% and 8.3% of the women, respectively. Concerns about its possible adverse effects on the physiology of reproduction or fetal development cannot be ruled out. It should be noted that skin-lightening creams and dental amalgam were important contributors to mercury exposure. Such finding is alarming and priority for further studies are, urgently, needed.

  1. A Comparative Study of Chromium and Cadmium Removal from Their Common Aqueous Solution by Batch Operation Using Tea Factory Waste as Adsorbent

    Directory of Open Access Journals (Sweden)

    Jibesh Datta

    2014-06-01

    Full Text Available The process of adsorption is a powerful tool for the treatment of industrial wastewater. In the recent years many studies have been conducted to evaluate the effectiveness of various locally available economical adsorbents for the removal of various heavy metals from the waste water. In the present study tea factory waste is used as adsorbent and its capacity to remove toxic heavy metals chromium and cadmium from their combined solution is investigated. Batch adsorption study is conducted to find the adsorption capacity of the adsorbent and the effect of the three important process parameters, i.e. agitation rate, adsorbent dose and initial metal ion concentration is evaluated. The maximum adsorption capacity of 24.88 mg/g and 23.92 mg/g is observed in case of cadmium and chromium respectively. It is also found that the removal efficiency of cadmium is higher than that of chromium in all cases. The experimental results are also found to be well fitted in the Langmuir and Freundlich Isotherm model.

  2. Gastrointestinal and in vitro release of copper, cadmium, indium, mercury and zinc from conventional and copper-rich amalgams

    Energy Technology Data Exchange (ETDEWEB)

    Brune, D. (NIOM, Scandinavian Institute of Dental Materials, Oslo, Norway); Gjerdet, N. (Department of Dental Materials, School of Dentistry, Bergen, Norway); Paulsen, G. (Denatal Faculty, University of Oslo, Norway)

    1983-01-01

    Particles of a conventional lathe-cut, a spherical non-gamma 2 and a copper amalgam have been gastrointestinally administered to rats for the purpose of evaluation of the dissolution resistance. The animals were sacrificed after 20 hrs. The contents of copper, cadmium, indium, mercury and zinc in kidney, liver, lung or blood were measured using nuclear tracer techniques. From a copper amalgam an extreme release of copper was demonstrated. This study simulates the clinical conditions of elemental release from swallowed amalgam particles after amalgam insertion or after removal of old amalgam fillings. Specimens of the same types of amalgams were also exposed to artificial saliva for a period of 10 days. The amounts of copper and mercury released were measured with flame and flameless atomic absorption spectrophotometry respectively. The levels of copper and mercury released from the copper amalgam were approximately 50 times those of the two other amalgam types studied.

  3. Relationships of cadmium, mercury, and selenium with nutrient reserves of female lesser scaup (Aythya affinis) during winter and spring migration

    Science.gov (United States)

    Anteau, M.J.; Afton, A.D.; Custer, Christine M.; Custer, T.W.

    2007-01-01

    Trace elements may have important effects on body condition of ducks during spring migration, because individuals are experiencing energetically costly events (e.g., migration, nutrient reserve accumulation, pair formation, feather molt, and ovarian follicle development). We examined relationships among hepatic cadmium, mercury, and selenium concentrations (??g/g dry wt) and nutrient reserves (lipid, protein, and mineral) of female lesser scaup (Aythya affinis) during winter and spring migration at four locations within the Mississippi Flyway (LA, IL, and MN, USA, and MB, Canada). Selenium concentrations (range, 3.73-52.29 (??g/g dry wt) were positively correlated with lipid reserves (F1,73 = 22.69, p lipid reserves (F1,73 = 6.92, p = 0.010, type III partial r2 = 0.09). The observed relationship between cadmium and lipid reserves may be cause for concern, because lipid reserves of females declined by 55 g (47%), on average, within the range of observed cadmium concentrations (0.23-7.24 ??g/g dry wt), despite the relatively low cadmium concentrations detected. Mean cadmium concentrations were higher in Minnesota (1.23 ??g/g dry wt) and Manitoba (1.11 ??g/g dry wt) than in Louisiana (0.80 ??g/g dry wt) and Illinois (0.69 ??g/g dry wt). However, mean cadmium concentrations predict lipid reserves of females to be only 11 g lower, on average, in Minnesota than in Illinois. Previous research documented that lipid reserves were 100 g lower in Minnesota than in Illinois; consequently, cadmium is unlikely to be the sole cause for decreases in lipid reserves of females during late-spring migration. ?? 2007 SETAC.

  4. Mercury and cadmium trigger expression of the copper importer Ctr1B, which enables Drosophila to thrive on heavy metal-loaded food.

    Science.gov (United States)

    Balamurugan, Kuppusamy; Hua, Haiqing; Georgiev, Oleg; Schaffner, Walter

    2009-02-01

    Organisms from insects to mammals respond to heavy metal load (copper, zinc, cadmium, and mercury) by activating the metal-responsive transcription factor 1 (MTF-1). MTF-1 binds to short DNA sequence motifs, termed metal response elements, and boosts transcription of a number of genes, notably those for metallothioneins. In Drosophila, MTF-1 somewhat counter-intuitively also activates transcription of a copper importer gene (Ctr1B) in response to copper starvation. Here, we report that mutant flies lacking Ctr1B are extremely sensitive to cadmium and mercury treatment, but can be rescued by excess copper in the food. We thus propose that copper, by competing for binding sites on cellular proteins, alleviates the toxic effects of mercury and cadmium. Such a scenario also explains a seemingly fortuitous metal response, namely, that cadmium and mercury strongly induce the expression of a Ctr1B reporter gene. Thus, the transcription enhancer/promoter region of the Ctr1B copper importer gene is subject to three modes of regulation. All of them depend on MTF-1 and all make biological sense, namely, (i) induction by copper starvation, (ii) repression by copper abundance, and (iii), as shown here, induction by cadmium or mercury at normal copper supply.

  5. Directional Solidification of Mercury Cadmium Telluride During the Second United States Microgravity Payload Mission (USMP-2)

    Science.gov (United States)

    Gillies, D. C.; Lehoczky, S. L.; Szofran, F. R.; Watring, D. A.; Alexander, H. A.; Jerman, G. A.

    1996-01-01

    As a solid solution semiconductor having, a large separation between liquidus and solidus, mercury cadmium telluride (MCT) presents a formidable challenge to crystal growers desiring an alloy of high compositional uniformity. To avoid constitutional supercooling during Bridgman crystal growth it is necessary to solidify slowly in a high temperature gradient region. The necessary translation rate of less than 1 mm/hr results in a situation where fluid flow induced by gravity on earth is a significant factor in material transport. The Advanced Automated Directional Solidification Furnace (AADSF) is equipped to provide the stable thermal environment with a high gradient, and the required slow translation rate needed. Ground based experiments in AADSF show clearly the dominance of flow driven transport. The first flight of AADSF in low gravity on USMP-2 provided an opportunity to test theories of fluid flow in MCT and showed several solidification regimes which are very different from those observed on earth. Residual acceleration vectors in the orbiter during the mission were measured by the Orbital Acceleration Research Experiment (OARE), and correlated well with observed compositional differences in the samples.

  6. Two-color detector: Mercury-cadmium-telluride as a terahertz and infrared detector

    Energy Technology Data Exchange (ETDEWEB)

    Sizov, F.; Zabudsky, V.; Petryakov, V.; Golenkov, A.; Andreyeva, K.; Tsybrii, Z. [Institute of Semiconductor Physics, 03028 Kiev (Ukraine); Dvoretskii, S. [Institute of Semiconductor Physics of SB RAS, 630090 Novosibirsk (Russian Federation)

    2015-02-23

    In this paper, issues associated with the development of infrared (IR) and terahertz (THz) radiation detectors based on HgCdTe are discussed. Two-color un-cooled and cooled to 78 K narrow-gap mercury-cadmium-telluride semiconductor thin layers with antennas were considered both as sub-THz (sub-THz) direct detection bolometers and 3–10 μm IR photoconductors. The noise equivalent power (NEP) for one of the detectors studied at ν ≈ 140 GHz reaches NEP{sub 300 K} ≈ 4.5 × 10{sup −10} W/Hz{sup 1/2} and NEP{sub 78 K} ≈ 5 × 10{sup −9} W/Hz{sup 1/2}. The same detector used as an IR photoconductor showed the responsivity at temperatures T = 78 K and 300 K with signal-to-noise ratio S/N ≈ 750 and 50, respectively, under illumination by using IR monochromator and globar as a thermal source.

  7. Mercury and cadmium in ringed seals in the Canadian Arctic: Influence of location and diet

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Tanya M., E-mail: tanya.brown@mun.ca [Memorial University of Newfoundland, St. John' s, Newfoundland A1B 3X9 (Canada); Fisk, Aaron T. [Great Lakes Institute of Environmental Research, University of Windsor, 401 Sunset Avenue, Windsor, Ontario N9B 3P4 (Canada); Wang, Xiaowa [Environment Canada, Canada Centre for Inland Waters, 867 Lakeshore Road, Burlington, Ontario L7R 4A6 (Canada); Ferguson, Steven H. [Fisheries and Oceans Canada, 501 University Crescent, Winnipeg, Manitoba R3T 2N6 (Canada); Young, Brent G. [University of Manitoba, 500 University Crescent, Winnipeg, Manitoba R3T 2N2 (Canada); Reimer, Ken J. [Environmental Sciences Group, Royal Military College of Canada, PO Box 17000, Stn Forces, Kingston, Ontario K7K 7B4 (Canada); Muir, Derek C.G. [Environment Canada, Canada Centre for Inland Waters, 867 Lakeshore Road, Burlington, Ontario L7R 4A6 (Canada)

    2016-03-01

    Concentrations of total mercury (THg) and total cadmium (TCd) were determined in muscle and liver of ringed seals (Pusa hispida) from up to 14 locations across the Canadian Arctic. Location, trophic position (TP) and relative carbon source best predicted the THg and TCd concentrations in ringed seals. THg concentrations in ringed seals were highest in the western Canadian Arctic (Beaufort Sea), whereas TCd was highest in the eastern Canadian Arctic (Hudson Bay and Labrador). A positive relationship between THg and TP and a negative relationship between THg and relative carbon source contributed to the geographical patterns observed and elevated THg levels at certain sites. In contrast, a negative relationship between TCd and TP was found, indicating that high TCd concentrations are related to seals feeding more on invertebrates than fish. Feeding ecology appears to play an important role in THg and TCd levels in ringed seals, with biomagnification driving elevated THg levels and a dependence on low-trophic position prey resulting in high TCd concentrations. The present study shows that both natural geological differences and diet variability among regions explain the spatial patterns for THg and TCd concentrations in ringed seals. - Highlights: • Diet and location influenced THg and Cd in ringed seals across the Canadian Arctic. • Biomagnification processes contribute to elevated THg levels in the western Arctic. • Consuming low-trophic position prey explains high Cd levels in the eastern Arctic.

  8. Optical behaviour of cadmium and mercury free eco-friendly lamp nanophosphor for display devices

    Directory of Open Access Journals (Sweden)

    Ratnesh Tiwari

    2014-01-01

    Full Text Available The present paper reports the synthesis of cadmium and mercury free lamp (Y, GdBO3: Eu3+ phosphor which is in nano range useful for display device application. The phosphor doped with Eu3+ was synthesized by the solid state reaction method which is suitable for large scale production and eco-friendly. The prepared phosphor was characterized by the X-ray diffraction technique (XRD, field emission gun scanning electron microscopy (FEGSEM and transmission electron microscopy (TEM. The optical behaviour of the prepared phosphor was determined by photoluminescence (PL spectra recorded in room temperature. The PL excitation spectra were found at 470 nm and the emission spectra cover all visible regions (419–625 nm which indicate that the prepared phosphor can act as a single host for white light emitting diode (WLED application and verified by Internationale de I’Eclairage (CIE techniques. The thermoluminescence (TL glow curve was recorded for Eu3+ doped (Y, GdBO3 phosphor. The TL glow curve was recorded for UV, beta and gamma irradiations and also the kinetic parameters were calculated. In addition to this trap parameters of prepared phosphor were studied using computerized glow curve deconvolution (CGCD.

  9. Macro-loading Effects in Inductively Coupled Plasma Etched Mercury Cadmium Telluride

    Science.gov (United States)

    Apte, Palash; Rybnicek, Kimon; Stoltz, Andrew

    2016-09-01

    This paper reports the effect of macro-loading on mercury cadmium telluride (Hg1- x Cd x Te) and Photoresist (PR) etched in an inductively coupled plasma (ICP). A significant macro-loading effect is observed, which affects the etch rates of both PR and Hg1- x Cd x Te. It is observed that the exposed silicon area has a significant effect on the PR etch rate, but not on the Hg1- x Cd x Te etch rate. It is also observed that the exposed Hg1- x Cd x Te area has a significant effect on the etch rate of the PR, but the exposed PR area does not seem to have an effect on the Hg1- x Cd x Te etch rate. Further, the exposed Hg1- x Cd x Te area is shown to affect the etch rate of the Hg1- x Cd x Te, but there does not seem to be a similar effect for the exposed PR area on the etch rate of the PR. Since the macro-loading affects the selectivity significantly, this effect can cause significant problems in the etching of deep trenches. A few techniques to reduce the effect of macro-loading on the etch rates of the PR and Hg1- x Cd x Te are listed, herein.

  10. Lead, mercury, and cadmium in umbilical cord serum and birth outcomes in Chinese fish consumers.

    Science.gov (United States)

    Tang, Mengling; Xu, Chenye; Lin, Nan; Liu, Kai; Zhang, Yongli; Yu, Xinwei; Liu, Weiping

    2016-04-01

    Heavy metals such as lead (Pb), mercury (Hg), and cadmium (Cd) were detected in the islands of Yangtze River estuary and Hangzhou bay and their exposure caused potential health risk for the residents. To assess the exposure levels of Pb, Hg, and Cd, the umbilical cord serum samples were collected from 103 mother-newborn pairs as the noninvasive specimens. The association of the concentration of Pb, Hg, and Cd with the birth outcomes was evaluated. Pb, Hg, and Cd had high exposure levels with the median concentrations at 76.20 μg L(-1) [interquartile range (IQR): 44.71, 115.80], 21.94 μg L(-1) (IQR: 15.10, 27.64), and 6.36 μg L(-1) (IQR: 3.63, 13.34), respectively. A unit increase in the Pb umbilical cord serum concentration (μg L(-1)) was significantly associated with a 0.29 cm (95% CI: -0.50, -0.09) decrease in birth height and a 0.22 cm (95%CI: -0.44, 0.00) decrease in head circumference. The middle tertile Pb and Hg exposure levels were found significantly negative effects on birth outcomes compared with low tertile exposure levels. Exposure to Cd showed no apparent effect on birth outcomes. Our results suggested that Pb and Hg exposure has potential adverse effects on birth outcomes in Chinese fish consumers from Yangtze River outlet and Hangzhou bay estuary regions.

  11. Effects of cadmium and mercury on the upper part of skeletal muscle glycolysis in mice.

    Directory of Open Access Journals (Sweden)

    Maria José Ramírez-Bajo

    Full Text Available The effects of pre-incubation with mercury (Hg(2+ and cadmium (Cd(2+ on the activities of individual glycolytic enzymes, on the flux and on internal metabolite concentrations of the upper part of glycolysis were investigated in mouse muscle extracts. In the range of metal concentrations analysed we found that only hexokinase and phosphofructokinase, the enzymes that shared the control of the flux, were inhibited by Hg(2+ and Cd(2+. The concentrations of the internal metabolites glucose-6-phosphate and fructose-6-phosphate did not change significantly when Hg(2+ and Cd(2+ were added. A mathematical model was constructed to explore the mechanisms of inhibition of Hg(2+ and Cd(2+ on hexokinase and phosphofructokinase. Equations derived from detailed mechanistic models for each inhibition were fitted to the experimental data. In a concentration-dependent manner these equations describe the observed inhibition of enzyme activity. Under the conditions analysed, the integral model showed that the simultaneous inhibition of hexokinase and phosphofructokinase explains the observation that the concentrations of glucose-6-phosphate and fructose-6-phosphate did not change as the heavy metals decreased the glycolytic flux.

  12. Evaluation of cadmium, chromium, nickel, and zinc in biological samples of psoriasis patients living in Pakistani cement factory area.

    Science.gov (United States)

    Afridi, Hassan Imran; Kazi, Tasneem Gul; Kazi, Naveed; Kandhro, Ghulam Abbas; Baig, Jameel Ahmed; Shah, Abdul Qadir; Khan, Sumaira; Kolachi, Nida Fatima; Wadhwa, Sham Kumar; Shah, Faheem; Jamali, Mohammad Khan; Arain, Mohammad Balal

    2011-09-01

    Psoriasis is a noncontiguous common and chronic skin disorder. The aim of the present study was to compare the level of trace elements cadmium (Cd), chromium (Cr), Nickel (Ni), and zinc (Zn) in biological samples (whole blood, urine, and scalp hair) of psoriasis patients of both gender age ranged (25-55 years) at mild, moderate severe, and more severe stage (n = 418) living in the vicinity of cement factory. For comparison purposes, healthy age-matched referent subjects, residents of industrial and non-industrial area, of both gender were also selected (n = 241). The concentrations of trace and toxic elements were measured by atomic absorption spectrophotometer prior to microwave-assisted acid digestion. The validity and accuracy of methodology was checked by using certified reference materials (CRMs) and conventional wet acid digestion method on same CRMs and real samples. The results of this study showed that the mean values of Cd, Cr, Ni, and Pb were significantly higher in scalp hair, blood, and urine samples of mild and severe psoriasis patients as compared to referents (p < 0.001), while the concentration of Zn was lower in the scalp hair and blood, but higher in the urine samples of psoriasis patients. The deficiency of Zn in psoriasis patients may be undoubtedly caused by the toxic element exposures via cement factory.

  13. Pilot study for utilization of dried blood spots for screening of lead, mercury and cadmium in newborns.

    Science.gov (United States)

    Chaudhuri, Sanwat N; Butala, Steven J M; Ball, R Wayne; Braniff, Christopher T

    2009-03-01

    The exposure of pregnant women and young children to environmental pollutants is an ongoing concern of state and local public health departments. Of primary concern is the exposure to lead in lead-based paints, methyl mercury in contaminated fish and cadmium present at mining sites. The feasibility, utility and methodology of using blood spot cards collected for new born health screening purposes was studied for use in conducting routine state-wide surveillance of blood lead, mercury and cadmium levels in infants. Homogeneity of different lots of blank filter paper was examined. Mass measurements (weights) of filter paper punches were taken across three different lots of filter paper. Statistical analysis of the data was performed using one-way ANOVA, which indicated no significant difference in the means of all three lots, but high variances were noted. The three metals were examined in three different lots of filter papers purchased from the manufacturer. The lots had measurable amounts of cadmium and lead, but not mercury. Lead spike values were observed for roughly about 7% of the blank samples, indicating heterogeneous distribution of this metal. Statistical analysis of the data was also performed using a two-way ANOVA calculation with Tukey's pairwise comparisons. The results found that total mean metal loadings across the three lots were different. The concentration of the metals can be different from each other and the concentration of any one metal can differ across lots. Stability at different concentrations of the heavy metals in blood spotted onto filter paper with time and storage conditions was examined. Results indicate acceptable performance for at least 8.5 months for lead (near CDC's concern level) and for mercury (near NRC's concern level). The filter paper and blood spots were analyzed for metals using an acid extraction, followed by analysis using an inductively coupled plasma mass spectrometer (ICP-MS). Blood spot cards were studied from four

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

    Science.gov (United States)

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

    2013-09-01

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

  15. Mercury

    Science.gov (United States)

    ... and treatments are needed. ELEMENTAL MERCURY Inhaled elemental mercury poisoning may be difficult to treat. The person may ... metals from the body INORGANIC MERCURY For inorganic mercury poisoning, treatment often begins with supportive care. The person ...

  16. Impact of synbiotic diets including inulin, Bacillus coagulans and Lactobacillus plantarum on intestinal microbiota of rat exposed to cadmium and mercury

    Directory of Open Access Journals (Sweden)

    Dornoush Jafarpour

    2015-09-01

    Full Text Available The aim of this study was to investigate the efficacy of two probiotics and a prebiotic (inulin on intestinal microbiota of rats exposed to cadmium and mercury. Fifty-four male Wistar rats were randomly divided into nine groups. All groups except control group were fed standard rat chow with 5% inulin and treated as follows: i control (standard diet, ii Lactobacillus plantarum- treated group (1×109 CFU/day, iii Bacillus coagulans-treated group (1×109 spores/day, iv cadmium-treated group (200 μg/rat/day, v L. plantarum and cadmium-treated group, vi B. coagulans and cadmium-treated group, vii mercury-treated group (10 μg/rat/day, viii L. plantarum and mercurytreated group, ix B. coagulans and mercurytreated group. Cadmium, mercury and probiotics were daily gavaged to individual rats for 42 days. Treatment effects on intestinal microbiota composition of rats were determined. Data showed that cadmium and mercury accumulation in rat intestine affected the gastrointestinal tract and had a reduction effect on all microbial counts (total aerobic bacteria, total anaerobic bacteria, total Lactic acid bacteria, L. plantarum and B. coagulans counts compared to the control group. It was also observed that application of synbiotics in synbiotic and heavy metals-treated groups had a significant effect and increased the number of fecal bacteria compared to the heavy metals groups. Based on our study, it can be concluded that L. plantarum and B. coagulans along with prebiotic inulin play a role in protection against cadmium and mercury inhibitory effect and have the potential to be a beneficial supplement in rats’ diets.

  17. Cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Stoeppler, M. (Kernforschungsanlage Juelich G.m.b.H. (Germany, F.R.). Inst. fuer Angewandte Physikalische Chemie); Piscator, M. (Karolinska Inst., Stockholm (Sweden). Dept. of Environmental Hygiene) (eds.)

    1988-01-01

    The proceedings contain the 18 papers presented at the workshop. They are dealing with the following themes: Toxicity, carcinogenesis and metabolism of cadmium, epidemiology; environmental occurrence; quantitative analysis and quality assessment. (MG) With 57 figs., 79 tabs.

  18. Daily intake of arsenic, cadmium, mercury, and lead by consumption of edible marine species.

    Science.gov (United States)

    Falcó, Gemma; Llobet, Juan M; Bocio, Ana; Domingo, José L

    2006-08-09

    The daily intake of arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) through the consumption of 14 edible marine species by the general population of Catalonia, Spain, was estimated. Health risks derived from this intake were also assessed. In March-April 2005, samples of sardine, tuna, anchovy, mackerel, swordfish, salmon, hake, red mullet, sole, cuttlefish, squid, clam, mussel, and shrimp were randomly acquired in six cities of Catalonia. Concentrations of As, Cd, Hg, and Pb were determined by ICP-MS. On the basis of recent fish and seafood consumption data, the daily intake of these elements was calculated for eight age/sex groups of the population. The highest As concentrations were found in red mullet, 16.6 microg/g of fresh weight, whereas clam and mussel (0.14 and 0.13 microg/g of fresh weight, respectively) were the species with the highest Cd levels. In turn, swordfish (1.93 microg/g of fresh weight) and mussel and salmon (0.15 and 0.10 microg/g of fresh weight) showed the highest concentrations of Hg and Pb, respectively. The highest metal intake through fish and seafood consumption corresponded to As (217.7 microg/day), Cd (1.34 microg/day), and Pb (2.48 microg/day) for male seniors, whereas that of Hg was observed in male adults (9.89 microg/day). The daily intake through fish and seafood consumption of these elements was compared with the provisional tolerable weekly intakes (PTWI). The intakes of As, Cd, Pb, and total Hg by the population of Catalonia were below the respective PTWI values. However, the estimated intake of methylmercury for boys, 1.96 microg/kg/week, was over the PTWI.

  19. Thin film cadmium telluride, zinc telluride, and mercury zinc telluride solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Chu, T.L. (University of South Florida, Tampa, FL (United States))

    1992-04-01

    This report describes research to demonstrate (1) thin film cadmium telluride solar cells with a quantum efficiency of 75% or higher at 0. 44 {mu}m and a photovoltaic efficiency of 11.5% or greater, and (2) thin film zinc telluride and mercury zinc telluride solar cells with a transparency to sub-band-gap radiation of 65% and a photovoltaic conversion efficiency of 5% and 8%, respectively. Work was directed at (1) depositing transparent conducting semiconductor films by solution growth and metal-organic chemical vapor deposition (MOCVD) technique, (2) depositing CdTe films by close-spaced sublimation (CSS) and MOCVD techniques, (3) preparing and evaluating thin film CdTe solar cells, and (4) preparing and characterizing thin film ZnTe, CD{sub 1-x}Zn{sub 1-x}Te, and Hg{sub 1-x}Zn{sub x}Te solar cells. The deposition of CdS films from aqueous solutions was investigated in detail, and their crystallographic, optical, and electrical properties were characterized. CdTe films were deposited from DMCd and DIPTe at 400{degrees}C using TEGa and AsH{sub 3} as dopants. CdTe films deposited by CSS had significantly better microstructures than those deposited by MOCVD. Deep energy states in CdTe films deposited by CSS and MOCVD were investigated. Thin films of ZnTe, Cd{sub 1- x}Zn{sub x}Te, and Hg{sub 1-x}Zn{sub x}Te were deposited by MOCVD, and their crystallographic, optical, and electrical properties were characterized. 67 refs.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Stephani [Division of Epidemiology and Biostatistics, Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH 45267 (United States); Arora, Monica [Department of Psychiatry, Creighton University School of Medicine, Omaha, NE 68131 (United States); Fernandez, Cristina [Department of Pediatrics, Creighton University School of Medicine, Omaha, NE 68131 (United States); Landero, Julio; Caruso, Joseph [Metallomics Center, Department of Chemistry, University of Cincinnati, Cincinnati, OH 45221 (United States); Chen, Aimin, E-mail: aimin.chen@uc.edu [Division of Epidemiology and Biostatistics, Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH 45267 (United States)

    2013-10-15

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

  1. Arsenic, cadmium, lead, and mercury in surface soils, Pueblo, Colorado: Implications for population health risk

    Science.gov (United States)

    Diawara, D.M.; Litt, J.S.; Unis, D.; Alfonso, N.; Martinez, L.A.; Crock, J.G.; Smith, D.B.; Carsella, J.

    2006-01-01

    Decades of intensive industrial and agricultural practices as well as rapid urbanization have left communities like Pueblo, Colorado facing potential health threats from pollution of its soils, air, water and food supply. To address such concerns about environmental contamination, we conducted an urban geochemical study of the city of Pueblo to offer insights into the potential chemical hazards in soil and inform priorities for future health studies and population interventions aimed at reducing exposures to inorganic substances. The current study characterizes the environmental landscape of Pueblo in terms of heavy metals, and relates this to population distributions. Soil was sampled within the city along transects and analyzed for arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb). We also profiled Pueblo's communities in terms of their socioeconomic status and demographics. ArcGIS 9.0 was used to perform exploratory spatial data analysis and generate community profiles and prediction maps. The topsoil in Pueblo contains more As, Cd, Hg and Pb than national soil averages, although average Hg content in Pueblo was within reported baseline ranges. The highest levels of As concentrations ranged between 56.6 and 66.5 ppm. Lead concentrations exceeded 300 ppm in several of Pueblo's residential communities. Elevated levels of lead are concentrated in low-income Hispanic and African-American communities. Areas of excessively high Cd concentration exist around Pueblo, including low income and minority communities, raising additional health and environmental justice concerns. Although the distribution patterns vary by element and may reflect both industrial and non-industrial sources, the study confirms that there is environmental contamination around Pueblo and underscores the need for a comprehensive public health approach to address environmental threats in urban communities. ?? Springer 2006.

  2. Thin film cadmium telluride, zinc telluride, and mercury zinc telluride solar cells

    Science.gov (United States)

    Chu, T. L.

    1992-04-01

    This report describes research to demonstrate (1) thin film cadmium telluride solar cells with a quantum efficiency of 75 percent or higher at 0.44 microns and a photovoltaic efficiency of 11.5 percent or greater, and (2) thin film zinc telluride and mercury zinc telluride solar cells with a transparency to sub-band-gap radiation of 65 percent and a photovoltaic conversion efficiency of 5 percent and 8 percent, respectively. Work was directed at (1) depositing transparent conducting semiconductor films by solution growth and metal-organic chemical vapor deposition (MOCVD) technique, (2) depositing CdTe films by close-spaced sublimation (CSS) and MOCVD techniques, (3) preparing and evaluating thin film CdTe solar cells, and (4) preparing and characterizing thin film ZnTe, CD(1-x)Zn(1-x)Te, and Hg(1-x)Zn(x)Te solar cells. The deposition of CdS films from aqueous solutions was investigated in detail, and their crystallographic, optical, and electrical properties were characterized. CdTe films were deposited from DMCd and DIPTe at 400 C using TEGa and AsH3 as dopants. CdTe films deposited by CSS had significantly better microstructures than those deposited by MOCVD. Deep energy states in CdTe films deposited by CSS and MOCVD were investigated. Thin films of ZnTe, Cd(1-x)Zn(x)Te, and Hg(1-x)Zn(x)Te were deposited by MOCVD, and their crystallographic, optical, and electrical properties were characterized.

  3. 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.

  4. Mercury-Cadmium-Telluride Focal Plane Array Performance Under Non-Standard Operating Conditions

    Science.gov (United States)

    Richardson, Brandon S.; Eastwood, Michael L.; Bruce, Carl F.; Green, Robert O.; Coles, J. B.

    2011-01-01

    This paper highlights a new technique that allows the Teledyne Scientific & Imaging LLC TCM6604A Mercury-Cadmium-Telluride (MCT) Focal Plane Array (FPA) to operate at room temperature. The Teledyne MCT FPA has been a standard in Imaging Spectroscopy since its creation in the 1980's. This FPA has been used in applications ranging from space instruments such as CRISM, M3 and ARTEMIS to airborne instruments such as MaRS and the Next Generation AVIRIS Instruments1. Precise focal plane alignment is always a challenge for such instruments. The current FPA alignment process results in multiple cold cycles requiring week-long durations, thereby increasing the risk and cost of a project. These alignment cycles are necessary because optimal alignment is approached incrementally and can only be measured with the FPA and Optics at standard operating conditions, requiring a cold instrument. Instruments using this FPA are normally cooled to temperatures below 150K for the MCT FPA to properly function. When the FPA is run at higher temperatures the dark current increases saturating the output. This paper covers the prospect of warm MCT FPA operation from a theoretical and experimental perspective. We discuss the empirical models and physical laws that govern MCT material properties and predict the optimal settings that will result in the best MCT PA performance at 300K. Theoretical results are then calculated for the proposed settings. We finally present the images and data obtained using the actual system with the warm MCT FPA settings. The paper concludes by emphasizing the strong positive correlation between the measured values and the theoretical results.

  5. Relationship between the level of zinc, lead, cadmium, nickel and chromium in hair of people with diabetes

    Directory of Open Access Journals (Sweden)

    Tadayon F.

    2014-07-01

    Full Text Available It has long been believed that some metals possess many adverse health effects. Recently, certain elements have been identified as essential trace elements that play an important role in the genesis and progression of several diseases. Some toxic metals have also been shown to be elevated in biological samples of diabetes mellitus patients. The status of trace elements in diabetes patients is also influenced by their diet, drugs administered and, to a large extent, by environmental factors. Pollutants due to the presence of toxic metals in environment not only enter the body by breading, water, and foodstuff accumulates in hair, but they could be adsorbed directly on the hair from environment. The aim of present study was to investigate the relationship between the level of zinc, lead, cadmium, nickel and chromium in hair samples of diabetic women from Tehran (Iran. The study population consisted of 100 women between 30 to 70 years of age from Tehran. The hair samples were washed with 1% (w/v (DDTC, 0.1M HCL and deionized water. Afterwards, the hair sample dried in oven at 70° C for 5 hours and then digested the next day. Dry ashing digestion procedure was carried out. The concentration of elements was measured by means of an atomic absorption spectrophotometer. The statistical analysis confirmed that mean concentrations of lead and nickel did not differ significantly from the control group. The results of this study showed that the mean values of Cr and Zn were significantly decreased in scalp hair samples of diabetic patients as compared to control subjects. Hair Cd level was significantly higher in type 2 diabetic patients. Values of Pearson correlation coefficient showed positive correlation between these elements.

  6. Response of two barley cultivars to increasing concentrations of cadmium or chromium in soil during the growing period.

    Science.gov (United States)

    González, A; Gil-Díaz, M; Lobo, M C

    2015-02-01

    The heavy metal contamination of soils is a serious environmental issue because excessive metal concentrations pose risks to the health of humans, animals, and plants. For this reason, the interest in understanding the toxic effects of metals on crop growth and physiology has increased in the last decades. A pot trial was performed in a greenhouse to evaluate the effects of contaminated soil with different concentrations of cadmium (Cd) or chromium (Cr) on barley growth and development. Two cultivars of barley were studied, Pedrezuela and CB502. Growth, chlorophyll content, chlorophyll fluorescence, and relative water content (RWC) were analyzed during the plant-growing period. After harvesting, the Cd and Cr contents in plant were analyzed. No significant differences were observed for chlorophyll content and chlorophyll fluorescence between control plants and those treated with Cd. In the case of Cr, a significant decrease of plant growth, chlorophyll content, chlorophyll fluorescence, and RWC was detected with respect to the control. The tolerance index (TI) and translocation factor (TF) were calculated. Data indicated that both varieties are tolerant to these metals; CB502 showed higher tolerance to Cr and Pedrezuela to Cd. The effect of Cd or Cr addition on nutrient concentrations in plants varied among elements and organs of the plant analyzed. The correlations between the physiological and agronomic studied traits were significant (p < 0.01, p < 0.001), so the stress induced by these metals affected the physiology and water relations of the plant, which provoked a decrease of plant biomass, especially in the plants treated with Cr.

  7. Concentrations of strontium, barium, cadmium, copper, zinc, manganese, chromium, antimony, selenium and lead in the equine liver and kidneys.

    Science.gov (United States)

    Paßlack, Nadine; Mainzer, Barbara; Lahrssen-Wiederholt, Monika; Schafft, Helmut; Palavinskas, Richard; Breithaupt, Angele; Neumann, Konrad; Zentek, Jürgen

    2014-01-01

    The concentrations of specific elements in the equine liver and kidneys are of practical relevance since horses are not only food-producing animals, but also partially serve as an indicator for the environmental pollution, as the basic feed includes plants like grass, grain and fruits. In this study, the concentrations of strontium (Sr), barium (Ba), cadmium (Cd), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), antimony (Sb), selenium (Se) and lead (Pb) were measured in the liver, renal cortex and renal medulla of 21 horses (8 male; 13 female; aged between 5 months-28 years), using inductively coupled plasma mass spectrometry. Comparable Cu and Zn concentrations were detected in the liver and renal cortex, while approximately 50% lower concentrations were measured in the renal medulla. The lowest Sr, Cd and Se, but the highest Mn, Sb and Pb concentrations were measured in the liver. The Ba concentrations were comparable in the renal cortex and medulla, but lower in the liver of the horses. Gender-related differences were observed for Cd, Mn and Cr, with higher Cd concentrations in the liver, but lower Mn concentrations in the renal cortex and lower Cr concentrations in the renal medulla of female horses. Age-related differences were detected for most measured elements, however, the animal number per age-group was only low. In conclusion, the present study provides important reference data for the storage of Sr, Ba, Cd, Cu, Zn, Mn, Cr, Sb, Se and Pb in the liver and kidneys of horses, which are of practical relevance for an evaluation of the exposure of horses to these elements, either via feed or the environment.

  8. Residues of chromium, nickel, cadmium and lead in Rook Corvus frugilegus eggshells from urban and rural areas of Poland

    Energy Technology Data Exchange (ETDEWEB)

    Orłowski, Grzegorz, E-mail: orlog@poczta.onet.pl [Institute of Agricultural and Forest Environment, Polish Academy of Sciences, Bukowska 19, 60-809 Poznań (Poland); Kasprzykowski, Zbigniew [Department of Ecology and Nature Protection, Siedlce University of Natural Sciences and Humanities, Prusa 12, 08-110 Siedlce (Poland); Dobicki, Wojciech; Pokorny, Przemysław [Department of Limnology and Fishery, Wrocław University of Environmental and Life Sciences, Chełmońskiego 38C, 51-630 Wrocław (Poland); Wuczyński, Andrzej [Institute of Nature Conservation, Polish Academy of Sciences, Lower-Silesian Field Station, Podwale 75, 50-449 Wrocław (Poland); Polechoński, Ryszard [Department of Limnology and Fishery, Wrocław University of Environmental and Life Sciences, Chełmońskiego 38C, 51-630 Wrocław (Poland); Mazgajski, Tomasz D. [Museum and Institute of Zoology, Polish Academy of Sciences, Wilcza 64, 00-679 Warszawa (Poland)

    2014-08-15

    We examined the concentrations of chromium (Cr), nickel (Ni), cadmium (Cd) and lead (Pb) in Rook Corvus frugilegus eggshells from 43 rookeries situated in rural and urban areas of western (= intensive agriculture) and eastern (= extensive agriculture) Poland. We found small ranges in the overall level of Cr (the difference between the extreme values was 1.8-fold; range of concentrations = 5.21–9.40 Cr ppm), Ni (3.5-fold; 1.15–4.07 Ni ppm), and Cd (2.6-fold; 0.34–0.91 Cd ppm), whereas concentrations of Pb varied markedly, i.e. 6.7-fold between extreme values (1.71–11.53 Pb ppm). Eggshell levels of these four elements did not differ between rural rookeries from western and eastern Poland, but eggshells from rookeries in large/industrial cities had significantly higher concentrations of Cr, Ni and Pb than those from small towns and villages. Our study suggests that female Rooks exhibited an apparent variation in the intensity of trace metal bioaccumulation in their eggshells, that rapid site-dependent bioaccumulation of Cu, Cr, Ni and Pb occurs as a result of the pollution gradient (rural < urban), and that Cd levels are probably regulated physiologically, even though these were relatively high, which could be treated as an overall proxy of a heavy Cd load in the soil environment. - Highlights: • Concentrations of Cr, Ni, Cd and Pb are reported for Rook eggshells from 43 rookeries. • Cr, Ni and Pb levels were significantly higher in urban than in rural areas. • Bioaccumulation of Cr, Ni and Pb suggests a pollution gradient (urban > rural areas). • Females rapidly bioaccumulate Cr, Ni and Pb in breeding areas. • No difference found for Cd levels, which are probably regulated physiologically.

  9. Contents of cadmium, mercury and lead in fish from the Atlantic sea (Morocco) determined by atomic absorption spectrometry.

    Science.gov (United States)

    Chahid, Adil; Hilali, Mustapha; Benlhachimi, Abdeljalil; Bouzid, Taoufiq

    2014-03-15

    As a part of a specific monitoring program, lead (Pb) cadmium (Cd) and mercury (Hg) concentrations in important species of fish from various fishing ports of the southern Kingdom of Morocco (Sardina pilchardus, Scomber scombrus, Plectorhinchus mediterraneus, Trachurus trachurus, Octopus vulgaris, Boops boops, Sarda sarda, Trisopterus capelanus, and Conger conger) were investigated by the Moroccan Reference Laboratory (NRL) for trace elements in foodstuffs of animal origin. The samples were analysed for lead and cadmium by a graphite furnace atomic absorption spectrometry (GFAAS); and for mercury by cold vapour atomic absorption spectrometry (CVAAS). The results were expressed as μg/g of wet weight (w/w). The levels of Cd, Pb and Hg in muscles of fish were 0.009-0.036, 0.013-0.114 and 0.049-0.194 μg/g, respectively. The present study showed that different metals were present in the sample at different levels but within the maximum residual levels prescribed by the EU for the fish and shellfish from these areas, in general, should cause no health problems for consumers.

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

    Science.gov (United States)

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

    2013-01-01

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

  11. Screening of Blood Levels of Mercury, Cadmium, and Copper in Pregnant Women in Dakahlia, Egypt: New Attention to an Old Problem.

    Science.gov (United States)

    Motawei, Shimaa M; Gouda, Hossam E

    2016-06-01

    Heavy metals toxicity is a prevalent health problem particularly in developing countries. Mercury and cadmium are toxic elements that have no physiologic functions in human body. They should not be present in the human body by any concentration. Copper, on the other hand, is one of the elements that are essential for normal cell functions and a deficiency as well as an excess of which can cause adverse health effects. To test blood levels of mercury, cadmium, and copper in pregnant women in Dakahlia, Egypt. Using atomic absorption spectrophotometry, blood levels of cadmium, mercury, and copper were measured in 150 pregnant women attending to the antenatal care in Mansoura University Hospital in Dakahlia governorate, Egypt. The mean ± SD of blood mercury, cadmium, and copper levels were found to be far from their levels in the population surveys carried in developed countries like United States of America (USA) and Canada. Heavy metal intoxication and accumulation is a major health hazard. Developing countries, including Egypt, still lack many of the regulatory policies and legislations to control sources of pollution exposure. This should be dealt with in order to solve this problem and limit its health consequences.

  12. Secondary poisoning of cadmium, copper and mercury: implications for the Maximum Permissible Concentrations and Negligible Concentrations in water, sediment and soil

    NARCIS (Netherlands)

    Smit CE; Wezel AP van; Jager T; Traas TP; CSR

    2000-01-01

    The impact of secondary poisoning on the Maximum Permissible Concentrations (MPCs) and Negligible Concentrations (NCs) of cadmium, copper and mercury in water, sediment and soil have been evaluated. Field data on accumulation of these elements by fish, mussels and earthworms were used to derive MPC

  13. Hair mercury and urinary cadmium levels in Belgian children and their mothers within the framework of the COPHES/DEMOCOPHES projects

    DEFF Research Database (Denmark)

    Pirard, Catherine; Koppen, Gudrun; De Cremer, Koen

    2014-01-01

    A harmonized human biomonitoring pilot study was set up within the frame of the European projects DEMOCOPHES and COPHES. In 17 European countries, biomarkers of some environmental pollutants, including urinary cadmium and hair mercury, were measured in children and their mothers in order to obtai...

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

    Science.gov (United States)

    Coulson, Dale M.; And Others

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

  15. Mercury

    Science.gov (United States)

    ... as chlorine, sulfur, or oxygen, to form inorganic mercury compounds or "salts," which are usually white powders or ... Mercury also combines with carbon to make organic mercury compounds. The most common one, methylmercury, is produced mainly ...

  16. Simultaneous preconcentration of cadmium and chromium(III) in water samples by cloud point extraction and their determination by flame atomic absorption spectrometry.

    Science.gov (United States)

    Meng, Lifen; Ning, Jinyan; Yang, Yaling

    2014-01-01

    A sensitive and simple method for flame atomic absorption spectrometry determination of traces of cadmium and chromium(III) species in water samples after preconcentration by cloud point extraction has been developed. A novel complex agent of alizarin complexone with cadmium (Cd) and chromium (Cr(III)) was quantitatively extracted in surface primary alcohol ethoxylate-rich phase at 33 °C. The effects of experimental conditions including pH of sample solution, concentration of chelating agent and salt, equilibration temperature and time, and foreign ions were evaluated in order to enhance sensitivity of the method. Under optimal conditions, the low limit detections were 6.7 and 3.2 μg/L, and the enrichment factors were 24 and 20 for Cd and Cr(III), respectively. The relative standard deviations were 3.8 and 2.5% for Cd and Cr(II), respectively (n = 11). The high recoveries of the spiked Cd and Cr(III) ions were obtained in the range of 90-116%. The proposed method has been successfully applied for the determination of Cd and Cr(III) in water samples.

  17. Estimation of Seasonal Risk Caused by the Intake of Lead, Mercury and Cadmium through Freshwater Fish Consumption from Urban Water Reservoirs in Arid Areas of Northern Mexico

    Directory of Open Access Journals (Sweden)

    Myrna Nevárez

    2015-02-01

    Full Text Available Bioavailability and hence bioaccumulation of heavy metals in fish species depends on seasonal conditions causing different risks levels to human health during the lifetime. Mercury, cadmium and lead contents in fish from Chihuahua (Mexico water reservoirs have been investigated to assess contamination levels and safety for consumers. Muscle samples of fish were collected across the seasons. Lead and cadmium were analyzed by inductively coupled plasma-optical emission spectrometry, and mercury by cold-vapor atomic absorption spectrometry. The highest concentrations of cadmium (0.235 mg/kg, mercury (0.744 mg/kg and lead (4.298 mg/kg exceeded the maximum levels set by European regulations and Codex Alimentarius. Lead concentrations found in fish from three water reservoirs also surpassed the limit of 1 mg/kg established by Mexican regulations. The provisional tolerable weekly intake (PTWI suggested by the World Health Organization for methyl mercury (1.6 µg/kg bw per week was exceeded in the spring season (1.94 µg/kg bw per week. This might put consumers at risk of mercury poisoning.

  18. Estimation of seasonal risk caused by the intake of lead, mercury and cadmium through freshwater fish consumption from urban water reservoirs in arid areas of northern Mexico.

    Science.gov (United States)

    Nevárez, Myrna; Leal, Luz O; Moreno, Myriam

    2015-02-04

    Bioavailability and hence bioaccumulation of heavy metals in fish species depends on seasonal conditions causing different risks levels to human health during the lifetime. Mercury, cadmium and lead contents in fish from Chihuahua (Mexico) water reservoirs have been investigated to assess contamination levels and safety for consumers. Muscle samples of fish were collected across the seasons. Lead and cadmium were analyzed by inductively coupled plasma-optical emission spectrometry, and mercury by cold-vapor atomic absorption spectrometry. The highest concentrations of cadmium (0.235 mg/kg), mercury (0.744 mg/kg) and lead (4.298 mg/kg) exceeded the maximum levels set by European regulations and Codex Alimentarius. Lead concentrations found in fish from three water reservoirs also surpassed the limit of 1 mg/kg established by Mexican regulations. The provisional tolerable weekly intake (PTWI) suggested by the World Health Organization for methyl mercury (1.6 µg/kg bw per week) was exceeded in the spring season (1.94 µg/kg bw per week). This might put consumers at risk of mercury poisoning.

  19. 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 ...

  20. Concentrations and health risks of lead, cadmium, arsenic, and mercury in rice and edible mushrooms in China.

    Science.gov (United States)

    Fang, Yong; Sun, Xinyang; Yang, Wenjian; Ma, Ning; Xin, Zhihong; Fu, Jin; Liu, Xiaochang; Liu, Meng; Mariga, Alfred Mugambi; Zhu, Xuefeng; Hu, Qiuhui

    2014-03-15

    In this study, four common heavy metals, lead (Pb), cadmium (Cd), arsenic (As) and mercury (Hg) in rice and edible mushrooms of China were studied to evaluate contamination level and edible safety. Ninety two (92) rice samples were collected from the main rice growing regions in China, and 38 fresh and 21 dry edible mushroom samples were collected from typical markets in Nanjing City. The analyzed metal concentrations were significantly different between rice and edible mushroom samples (pmushroom, Pb and Hg contents in 2.6% samples were above MAC, respectively. However, only Hg content in 4.8% dry edible mushroom samples was above its MAC. Therefore, more than 95% rice and edible mushroom samples in our test had high edible safety.

  1. The phytochelatin transporters AtABCC1 and AtABCC2 mediate tolerance to cadmium and mercury.

    Science.gov (United States)

    Park, Jiyoung; Song, Won-Yong; Ko, Donghwi; Eom, Yujin; Hansen, Thomas H; Schiller, Michaela; Lee, Tai Gyu; Martinoia, Enrico; Lee, Youngsook

    2012-01-01

    Heavy metals such as cadmium (Cd) and mercury (Hg) are toxic pollutants that are detrimental to living organisms. Plants employ a two-step mechanism to detoxify toxic ions. First, phytochelatins bind to the toxic ion, and then the metal-phytochelatin complex is sequestered in the vacuole. Two ABCC-type transporters, AtABCC1 and AtABCC2, that play a key role in arsenic detoxification, have recently been identified in Arabidopsis thaliana. However, it is unclear whether these transporters are also implicated in phytochelatin-dependent detoxification of other heavy metals such as Cd(II) and Hg(II). Here, we show that atabcc1 single or atabcc1 atabcc2 double knockout mutants exhibit a hypersensitive phenotype in the presence of Cd(II) and Hg(II). Microscopic analysis using a Cd-sensitive probe revealed that Cd is mostly located in the cytosol of protoplasts of the double mutant, whereas it occurs mainly in the vacuole of wild-type cells. This suggests that the two ABCC transporters are important for vacuolar sequestration of Cd. Heterologous expression of the transporters in Saccharomyces cerevisiae confirmed their role in heavy metal tolerance. Over-expression of AtABCC1 in Arabidopsis resulted in enhanced Cd(II) tolerance and accumulation. Together, these results demonstrate that AtABCC1 and AtABCC2 are important vacuolar transporters that confer tolerance to cadmium and mercury, in addition to their role in arsenic detoxification. These transporters provide useful tools for genetic engineering of plants with enhanced metal tolerance and accumulation, which are desirable characteristics for phytoremediation.

  2. Environmental consequences of the inhibition in the hatching of pupae of Aedes aegypti by mercury, zinc, and chromium - the abnormal toxicity of zinc

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, S.A.; Nipaney, P.C.; Soni, R.

    1985-01-01

    In continuation of our studies on the toxicity of heavy metals the authors report the impact of mercury (II), zinc (II), and chromium (VI) on hatching of the pupae of mosquito Aedes aegypti. The studies were carried out in terms of abnormal responses in swimming and flying, incompleteness of the metamorphosis and mortality - all with respect to controls. The toxicity trend with respect to the mortality of pupae in partially or completely hatched conditions, as also with respect to reduction in the number of pupae reaching the mosquito stage was Hg > Zn approx. = Cr. A comparison of lethal doze values of the metals obtained through present experiments with the levels allowable in irrigation waters, indicate that the permissible levels of zinc and chromium are higher by several orders of magnitude than the lowest lethal concentrations for pupae of A. aegypti. The studies thus point to a need for the revision of the existing standards.

  3. A temperature responsive biopolymer for mercury remediation.

    Science.gov (United States)

    Kostal, Jan; Mulchandani, Ashok; Gropp, Katie E; Chen, Wilfred

    2003-10-01

    Tunable biopolymers based on elastin-like polypeptides (ELP) were engineered for the selective removal of mercury. ELP undergoes a reversible thermal precipitation within a wide range of temperatures and was exploited to enable easy recovery of the sequestered mercury. A bacterial metalloregulatory protein, MerR, which binds mercury with an unusually high affinity and selectivity, was fused to the ELP to provide the highly selective nature of the biopolymers. Selective binding of mercury was demonstrated at an expected ratio of 0.5 mercury/biopolymer, and minimal binding of competing heavy metals (cadmium, nickel, and zinc), even at 100-fold excess, was observed. The sequestered mercury was extracted easily, enabling continuous reuse of the biopolymers. In repeating cycles, mercury concentration was reduced to ppb levels, satisfying even drinking water limits. Utility of the biopolymers with mercury-contaminated Lake Elsinore water was demonstrated with no decrease in efficiency. The nanoscale biopolymers reported here using metalloregulatory proteins represent a "green" technology for environmentally benign mercury removal. As nature offers a wide selection of specific metalloregulatory proteins, this technology offers promising solutions to remediation of other important pollutants such as arsenic or chromium.

  4. Bioassessment of mercury, cadmium, polychlorinated biphenyls, and pesticides in the upper Mississippi River with zebra mussels (Dreissena polymorpha)

    Science.gov (United States)

    Cope, W. Gregory; Bartsch, Michelle; Rada, Ronald G.; Balogh, Steven J.; Rupprecht, John E.; Young, R. David; Johnson, D. Kent

    1999-01-01

    Zebra mussels (Dreissena polymorpha) were sampled from artificial substrates deployed from May 30 to October 19, 1995, at 19 locks and dams from Minneapolis, MN, to Muscatine, IA. Analyses of composite tissue samples of zebra mussels (10-20-mm length) revealed accumulation of mercury(Hg), cadmium (Cd), and polychlorinated biphenyls (PCBs) during a 143-d exposure period. Concentrations of total Hg ranged from 2.6 to 6.1 ng/g wet weight and methylmercury (CH3Hg) from 1.0 to 3.3 ng/g wet weight. About 50% (range 30-70%) of the mean total Hg in zebra mussels was CH3Hg. Cadmium ranged from 76 to 213 ng/g wet weight. Concentrations of total PCBs (Aroclor 1254) in zebra mussels varied longitudinally (range 1000-7330 ng/g lipid weight), but the composition of PCB congeners (total of 21 measured) was similar throughout the river. Chlordane and dieldrin were the only two pesticides detected of the 15 analyzed. Zebra mussels are sentinels of contaminant bioavailability in the Upper Mississippi River and may be an important link in the trophic transfer of contaminants in the river because of their increasing importance in the diets of certain fish and waterfowl.

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

    Science.gov (United States)

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

    1998-08-14

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

  6. Assessing toxicity of copper, cadmium and chromium levels relevant to discharge limits of industrial effluents into inland surface waters using common onion, Allium cepa bioassay.

    Science.gov (United States)

    Hemachandra, Chamini K; Pathiratne, Asoka

    2015-02-01

    Toxicity of copper, cadmium and chromium relevant to established tolerance limits for the discharge of industrial effluents into inland surface waters was evaluated by Allium cepa bioassay. The roots of A. cepa bulbs exposed to Cu(2+) (3 mg L(-1)) individually or in mixtures with Cd(2+) (0.1 mg L(-1)) or/and Cr(6+) (0.1 mg L(-1)) exhibited the highest growth inhibition, mitotic index depression and nuclear abnormalities. Root tip cells exposed to Cr(6+) or Cd(2+) alone or in mixture displayed significant chromosomal aberrations in comparison to the controls. EC50s for root growth inhibition followed the order Cu(2+) < Cd(2+) < Cr(6+) indicating greater toxicity of copper. The results show that the industrial effluent discharge regulatory limits for these metals need to be reviewed considering potential cyto-genotoxicity to biological systems.

  7. Determination of Pb (Lead, Cd (Cadmium, Cr (Chromium, Cu (Copper, and Ni (Nickel in Chinese tea with high-resolution continuum source graphite furnace atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Wen-Si Zhong

    2016-01-01

    Full Text Available The contents of lead, cadmium, chromium, copper, and nickel were determined in 25 tea samples from China, including green, yellow, white, oolong, black, Pu'er, and jasmine tea products, using high-resolution continuum source graphite furnace atomic absorption spectrometry. The methods used for sample preparation, digestion, and quantificational analysis were established, generating satisfactory analytical precisions (represented by relative standard deviations ranging from 0.6% to 2.5% and recoveries (98.91–101.32%. The lead contents in tea leaves were 0.48–10.57 mg/kg, and 80% of these values were below the maximum values stated by the guidelines in China. The contents of cadmium and chromium ranged from 0.01 mg/kg to 0.39 mg/kg and from 0.27 mg/kg to 2.45 mg/kg, respectively, remaining in compliance with the limits stipulated by China's Ministry of Agriculture. The copper contents were 7.73–63.71 mg/kg; only 64% of these values complied with the standards stipulated by the Ministry of Agriculture. The nickel contents ranged from 2.70 mg/kg to 13.41 mg/kg. Consequently, more attention must be paid to the risks of heavy metal contamination in tea. The quantitative method established in this work lays a foundation for preventing heavy metal toxicity in human from drinking tea and will help establish regulations to control the contents of heavy metals in tea.

  8. Influence of bioaccessibility on the toxicity of heavy metal (nickel, chromium, cadmium and lead) species; Einfluss der Resorptionsverfuegbarkeit auf die Toxizitaet von Verbindungen der Schwermetalle Nickel, Chrom, Cadmium und Blei

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, K.; Oltmanns, J.; Kalberlah, F. [FoBiG Forschungs- und Beratungsinstitut Gefahrstoffe GmbH, Freiburg im Breisgau (Germany); Voss, J.U. [Toxikologische Beratung, Chemikalienbewertung - Risikoabschaetzung, Muellheim (Germany)

    2001-07-01

    The risk assessment of heavy metals at hazardous waste sites is based on total elemental concentrations in the soil without differentiation of metal species. This literature study investigates the correlation between bioaccessibility and toxicity of compounds of the heavy metals nickel, chromium, cadmium and lead with low water solubility. Chronic oral toxicity studies for sparsely soluble species are generally lacking. Only for chromic oxide (Cr{sub 2}O{sub 3}) derivation of a tolerable daily dose is possible based on chronic toxicity studies. The chronic oral toxicity of water-soluble chromium-III-compounds can be assessed by comparing effective doses with well-studied, highly toxic Cr-VI-compounds. In general, lower water-solubility is correlated with lower bioaccessibility and lower toxicity in case of the sulfides of nickel, lead and cadmium (and also with nickel oxide and lead chromate). However, some carbonates, oxides and hydroxides (lead oxide, lead carbonate, cadmium oxide, cadmium carbonate, nickel carbonate, nickel hydroxide) show a better solubility in biological media and higher toxicity than expected based solely on poor water solubility. This can be explained by a higher solubility of these compounds in acid environments. Compounds with poor water solubility like nickel oxide and cadmium sulfide are absorbed only to a minor extent from the respiratory tract after inhalation. However, absorption in the respiratory tract is not strictly correlated with bioaccessibility in the gastrointestinal tract. The influence of absorption on respiratory toxicity and on lung carcinogenicity of the heavy metals differs. For example, nickel sulfate, a compound with high water solubility, was toxic in the respiratory tract by inhalation, but not carcinogenic, whereas nickel subsulfide, a compound with lower water solubility, induced lung tumours. For the risk assessment of hazardous waste sites this means that results of in vitro digestive models (for the

  9. Inhibition of acetylcholinesterase activity in the central nervous system of the red swamp crayfish, Procambarus clarkii, by mercury, cadmium, and lead

    Energy Technology Data Exchange (ETDEWEB)

    Devi, M.; Fingerman, M. [Tulane Univ., New Orleans, LA (United States)

    1995-11-01

    The toxicological, physiological and biochemical responses of aquatic crustaceans to heavy metals have been reported by several investigators. Levels of glucose, lactic acid, sodium, potassium, aspartate aminotransferase and alanine aminotransferase in the blood of the crab Scylla serrata increased, while glycogen levels in hepatopancreas and muscle decreased after a four-week exposure to mercuric chloride. In fiddler crab, Uca pugilator, enzyme activity was observed to decrease in the hepatopancreas but increased in abdominal muscle after 48 hr cadmium exposure. In the red swamp crayfish, Procambarus clarkii, exposed for 96 hr to cadmium, glutahione (GSH) level and GSH S-transferase activity deceased in the midgut. In crayfish Astacus astacus exposed to sublethal concentrations of lead and cadmium, oxidative enzyme (succine dehydrogenase and NADPH-cytochrome P450 reductase) activities in gills and hepatopancrease decreased. Acetylcholinesterase (AChE) inhibition by organophosphates and organocarbamates in various crustaceans has bee reported. In vivo cadmium exposure caused increases in esterase activities, but mercury exposure decreases these activities in the hepatopancreas of the shrimp Callianassa tyrrhena. The freshwater crab, Barytelphusa guerini, exposed to 0.6 ppm cadmium showed reduced oxygen consumption throughout the experiment whereas AChE activity increased after 4 days but decreased after 15 days. The authors wanted to determine the effects of cadmium, lead and mercury on AChE activity in central nervous tissue of Procambarus clarkii. This enzyme has the potential for serving both as a biochemical indicator of toxic stress and a sensitive parameter for testing water for the presence of toxicants. These three biologically silent metals have, according to Schweinsberg and Karsa great toxicological significance to humans because their use is widespread. 14 refs., 4 figs.

  10. Biosorption of mercury by Macrocystis pyrifera and Undaria pinnatifida: Influence of zinc, cadmium and nickel

    Institute of Scientific and Technical Information of China (English)

    Josefina Plaza; Marisa Viera; Edgardo Donati; Eric Guibal

    2011-01-01

    This study investigated the adsorption of Hg(Ⅱ) on Macrocystis pyrifera and Undaria pinnatifida in monometallic system in the presence of Zn(Ⅱ),Cd(Ⅱ) and Ni(Ⅱ).The two biosorbents reached the same maximum sorption capacity (qm =0.8 mmol/g) for mercury.U.pinnatifida showed a greater affinity (given by the coefficient b of the Langmuir equation) for mercury compared to M.pyrifera (4.4 versus 2.7 L/mmol).Mercury uptake was significantly reduced (by more than 50%) in the presence of competitor heavy metals such as Zn(Ⅱ),Cd(Ⅱ) and Ni(Ⅱ).Samples analysis using an environmental scanning electron microscopy equipped with an energy dispersive X-ray microanalysis showed that mercury was heterogeneously adsorbed on the surface of both biomaterials,while the other heavy metals were homogeneous distributed.The analysis of biosorbents by Fourier transform infrared spectrometry indicated that Hg(Ⅱ)binding occurred on S=O (sulfonate) and N-H (amine) functional groups.

  11. Cadmium and mercury accumulation in European hare (Lepus europaeus): age-dependent relationships in renal and hepatic tissue.

    Science.gov (United States)

    Petrović, Zoran; Teodorović, Vlado; Djurić, Spomenka; Milićević, Dragan; Vranić, Danijela; Lukić, Mirjana

    2014-12-01

    A total of 63 European hares have been collected from five Serbian agricultural regions. The hares assayed were divided into four age groups (3-6 months, 12 months, 12-24 months, and 24-36 months) and investigated upon presence at cadmium (Cd) and mercury (Hg) in the kidney and liver. The positive significant correlation (Ps-Pearson's coefficient) between Cd concentrations in the kidney and liver within age group the 3-6 months was found (Ps = 0.81, p 0.05). Statistically significant differences were registered between Hg content in the liver of the hares aged 24-36 and 12 months (p 0.05). The strong statistically significant associations were registered between Cd and Hg content in the liver (Cd L/Hg L) in the age group 3-6 and 12-24 months (Cd L/Hg L, Ps = 0.94; p < 0.001 and Ps = 0.91; p < 0.001, respectively). The polynomial regression model used for graphing the observed data seems to be a method for modeling the relationship between measured Cd and Hg concentrations in the liver and kidney as first approximation for bioaccumulation in hares.

  12. Interaction of selenium with cadmium and mercury in semen and reproductive tissues: in vivo and in vitro studies

    Energy Technology Data Exchange (ETDEWEB)

    Alabi, N.S.

    1984-01-01

    Studies were conducted to investigate the metabolism of selenium (Se), and the influences of Se on the metabolism of cadmium (Cd) and inorganic mercury (Hg) in rats, and in ram semen in vitro. Se-deficient (-Se) or Se-adequate (+Se) rats were injected intraperitoneally with either /sup 109/CdCl/sub 2/ or /sup 203/HgNO/sub 3/. Semen ejaculates from yearling Suffolk rams were used for the in vitro studies. Whole-body retention of Cd and Hg in rats was significantly increased by Se. However, regardless of the Se status, the predominant route of Cd and Hg excretion was feces. Data on whole tissue Cd retention for both -Se and +Se rats gave the following order of decreasing tissue Cd levels: liver > kidney > testis > epididymis > seminal vesicles > prostate > brain. Cd and Hg concentrations ranging from 10/sup -6/ to 10/sup -2/ M were shown to be injurious to ram sperm in vitro as indicated by the depressed motility and reduced oxygen uptake.

  13. Mercury, lead and cadmium levels in the urine of 170 Spanish adults: a pilot human biomonitoring study.

    Science.gov (United States)

    Castaño, Argelia; Sánchez-Rodríguez, Jinny E; Cañas, Ana; Esteban, Marta; Navarro, Carmen; Rodríguez-García, Ana C; Arribas, Misericordia; Díaz, Gema; Jiménez-Guerrero, José A

    2012-02-01

    Human biomonitoring is a well-recognized tool for estimating the exposure of human populations to environmental pollutants. However, information regarding biomarker concentrations of many environmental chemicals in the general population is limited for many countries. The Spanish Environment Ministry has recently funded a human biomonitoring study on the Spanish general population. This study aims to determine reference levels for several biomarkers, especially heavy metals, persistent organic pollutants (POPs) and cotinine, in urine, whole blood, serum and hair, and will involve 2000 volunteers throughout Spain. Samples were taken during 2009-2010 and analyses are currently underway. The results presented herein were obtained in a pilot study carried out in the Madrid region. The study group comprised 170 volunteers, of which 79% were female and 21% male (age: 23-66 years). All participants were asked to complete a questionnaire regarding diet and living habits and provides a morning urine sample. The geometric means for total mercury (Hg), lead (Pb) and cadmium (Cd) were 1.23, 1.11 and 0.25 μg/g creatinine, respectively. Levels of Pb and Hg were higher than those reported for the general population in the USA and Germany, whereas Cd was in the same range (CDC, 2009; Becker et al., 2003). The values reported here are similar to those reported in other Spanish studies.

  14. Concentration of lead, cadmium, and mercury in tissues of European beaver (Castor fiber from the north-eastern Poland

    Directory of Open Access Journals (Sweden)

    Giżejewska Aleksandra

    2014-03-01

    Full Text Available The aim of the study was to determine the concentrations of lead (Pb, cadmium (Cd, and mercury (Hg in the liver, kidneys, and muscles of European beavers (Castor fiber and thus to evaluate the degree of heavy metals contamination in Warmia and Mazury region in Poland. The study was conducted on free-living beavers captured in region of Warmia and Mazury during autumn 2011. Concentrations of the elements were determined by atomic absorption spectrometry. The presence of the metals was detected in all individual tissue samples. Mean Pb and Hg concentrations were relatively low. However, the high mean Cd level, especially in the kidneys (7.933 mg/kg and liver (0.880 mg/kg was demonstrated. Despite the fact that region of Warmia and Mazury is considered to be “ecologically clean”, the conducted studies indicate that systematic monitoring for the presence of heavy metals is necessary not only in industrialised but also in agricultural regions, as well as in natural ecosystems.

  15. Determination of arsenic, cadmium, cobalt, chromium, lead, molybdenum, nickel, and selenium in fertilizers by microwave digestion and inductively coupled plasma-optical emission spectrometry detection: collaborative study.

    Science.gov (United States)

    Kane, Peter F; Hall, William L

    2006-01-01

    There is increasing regulatory interest in the non-nutritive metals content of fertilizer materials, but at present there is no consensus analytical method for acid digestion and instrument detection of those elements in fertilizer matrixes. This lack of method standardization has resulted in unacceptable variability of results between fertilizer laboratories performing metals analysis. A method has been developed using microwave digestion with nitric acid at 200 degrees C, followed by inductively coupled plasma-optical emission spectrometry instrument detection, for the elements arsenic, cadmium, cobalt, chromium, molybdenum, nickel, lead, and selenium. The method has been collaboratively studied, and statistical results are here reported. Fourteen collaborators were sent 62 sample materials in a blind duplicate design. Materials represented a broad cross section of fertilizer types, including phosphate ore, manufactured phosphate products, N-P-K blends, organic fertilizers, and micro-nutrient materials. As much as possible within the limit of the number of samples, materials were selected from different regions of the United States and the world. Limit of detection (LOD) was determined using synthetic fertilizers consisting of reagent grade chemicals with near zero levels of the non-nutritive elements, analyzed blindly. Samples with high iron content caused the most variability between laboratories. Most samples reasonably above LOD gave HorRat values within the range 0.5 to 2.0, indicating acceptable method performance according to AOAC guidelines for analyses in the mg/kg range. The method is recommended for AOAC Official First Action status.

  16. Preconcentration and separation of copper(II), cadmium(II) and chromium(III) in a syringe filled with 3-aminopropyltriethoxysilane supported on silica gel.

    Science.gov (United States)

    Tokman, Nilgun; Akman, Suleyman; Ozcan, Mustafa; Koklu, Unel

    2002-11-01

    In this study, a syringe was filled with silica gel loaded with 3-aminopropyltriethoxysilane, for the separation and preconcentration of copper, cadmium and chromium prior to their determination by graphite furnace atomic absorption spectrometry (GFAAS) in seawater. For this purpose, a syringe was filled with 0.5 g of modified silica gel and the sample solution was drawn into the syringe and ejected back again. The analyte elements were quantitatively retained at pH 5. Then, the elements sorbed by the silica gel were eluted with 2.0 M of HCl and determined by GFAAS. At optimum conditions, the recovery of Cu, Cd and Cr were 96-98%. Detection limits (3delta) were 6.6, 7.5 and 6.0 micro g L(-1) for Cu, Cd and Cr, respectively. The elements could be concentrated by drawing and discharging several portions of sample successively but eluting only once. Cu, Cd and Cr added to a seawater sample were quantitatively recovered (>95%) in the range of the 95% confidence level. The method proposed in this paper was compared with a column technique. Optimum experimental conditions, reproducibility, precision and recoveries of both techniques are the same, but the syringe technique is much faster, easier and more practical than the column technique. It is a portable system and allows one to make the sorption process in the source of sample. In addition, the risk of contamination is less than in the column technique.

  17. Accumulation of lead, chromium, and cadmium in muscle of capitán (Eremophilus mutisii), a catfish from the Bogota River basin.

    Science.gov (United States)

    Rodríguez Forero, Adriana; González Mantilla, Jaime Fernando; Suárez Martínez, Roger

    2009-08-01

    Heavy metal accumulation of lead (Pb), chromium (Cr), and cadmium (Cd) in the muscle of the catfish Eremophilus mutisii was studied in 47 specimens, captured by anglers in the Bogotá River at two sampling sites (Chocontá and Suesca) during May-October 2005. Water samples were processed for physicochemical and metal analyses. Metal accumulation in muscle (wet weight) of specimens at Chocontá and Suesca showed high levels of Pb (3.4 and 3.1 ppm, respectively), Cr (1.8 and 2.1 ppm, respectively), and Cd (0.35 and 0.48, respectively). Metal levels in waters (ppm) indicated that average Pb (0.028 Chocontá, 0.029 Suesca), Fe (0.462 Chocontá, 1.1 Suesca), and Cr (0.113 Chocontá) were above the maximum levels (MCLs) allowed in drinking waters. No extreme average values were found for pH, nitrites, alkalinity, and hardness in the waters. This study showed the importance of benthic and nonmigratory species like the capitán to evaluate the effects of heavy metals pollution. Further public health implications could be derived in the region where this investigation took place due to consumption of capitán by people in the area.

  18. Cadmium complexes bearing (Me2)N^E^O(-) (E = S, Se) organochalcogenoalkoxides and their zinc and mercury analogues.

    Science.gov (United States)

    Pop, Alexandra; Bellini, Clément; Şuteu, Răzvan; Dorcet, Vincent; Roisnel, Thierry; Carpentier, Jean-François; Silvestru, Anca; Sarazin, Yann

    2017-03-07

    Heteroleptic zinc and cadmium complexes of the type [{(Me2)N^E^O(R2)}M-Nu]n (M = Zn, Cd; E = S, Se; R = CH3, CF3; Nu = N(SiMe3)2, I, Cl; n = 1-2) were prepared by reacting the alcohol proteo-ligands {(Me2)N^E^O(R2)}H with [M(N(SiMe3)2)2] (M = Zn, Cd) or [XMN(SiMe3)2] (M = Zn, X = Cl; M = Cd, X = I) in an equimolar ratio. These group 12 metal complexes were characterised in solution by multinuclear NMR spectroscopy and their solid-state structures were determined by X-ray diffractometry. The ligands {(Me2)N^E^O((CH3)2)}(-) bearing CH3 groups in α position to the alkoxide behave as κ(2)-O,E-bidentate moieties (E = S, Se) and form centro-symmetric dinuclear O-bridged heteroleptic alkoxo-amido complexes both with zinc and cadmium, with four-coordinate metal centres resting in tetrahedral environments. By contrast, complexes supported by the CF3-substituted {(Me2)N^E^O((CF3)2)}(-) crystallise as tetrahedral mononuclear species, with tridentate κ(3)-N,O,E-coordinated ligands. These structural differences resulting from changes in the ligand skeleton and in the electron-donating properties of the alkoxide were also observed in solution. Attempts to prepare congeneric heteroleptic mercury complexes from [Hg(N(SiMe3)2)2] unexpectedly only afforded homoleptic bis(alkoxide)s such as [{(Me2)N^S^O((CF3)2)}2Hg]. Owing to the strong Hg-C bond, treatment of [PhHgN(SiMe3)2] with {(Me2)N^S^O((CF3)2)}H afforded the heteroleptic, T-shaped [{(Me2)N^S^O((CF3)2)}HgPh] mercuric alkoxide upon elimination of hexamethyldisilazane. [{(Me2)N^S^O((CF3)2)}2Hg] and [{(Me2)N^S^O((CF3)2)}HgPh] constitute very rare examples of structurally characterised mercuric alkoxides.

  19. Comparison of pollutant emission control strategies for cadmium and mercury in urban water systems using substance flow analysis.

    Science.gov (United States)

    Revitt, D M; Lundy, L; Eriksson, E; Viavattene, C

    2013-02-15

    The European Union (EU) Water Framework Directive (WFD) requires Member States to protect inland surface and groundwater bodies but does not directly stipulate how the associated environmental quality standards should be achieved. This paper develops and assesses the performance of a series of urban emission control strategies (ECS) with an emphasis on the scientific and technological benefits which can be achieved. Data from the literature, in combination with expert judgement, have been used to develop two different semi-hypothetical case cities (SHCC), which represent virtual platforms for the evaluation of ECS using substance flow analysis (SFA). The results indicate that the full implementation of existing EU legislation is capable of reducing the total emissions of cadmium (Cd) and mercury (Hg) by between 11% and 20%. The ability to apply voluntary reduction practices is shown to be particularly effective for Cd with the potential to further lower the overall emissions by between 16% and 27%. The most efficient protection of the receiving surface water environment is strongly influenced by the city characteristics with the introduction of stormwater treatment practices being particularly effective for one city (59% reduction of Hg; 39% reduction of Cd) and the other city being most influenced by the presence of efficient advanced wastewater treatment processes (63% reduction of Hg; 43% reduction of Cd). These reductions in receiving water loads are necessarily accompanied by either increases in stormwater sediment loadings (2.6-14.9 kg/year or 0.6-2.4 kg/year for Hg) or wastewater sludge loadings (45.8-57.2 kg/year or 42.0-57.4 kg/year for Cd).

  20. The cadmium-tolerant pea (Pisum sativum L.) mutant SGECdt is more sensitive to mercury: assessing plant water relations.

    Science.gov (United States)

    Belimov, Andrey A; Dodd, Ian C; Safronova, Vera I; Malkov, Nikita V; Davies, William J; Tikhonovich, Igor A

    2015-04-01

    Heavy metals have multiple effects on plant growth and physiology, including perturbation of plant water status. These effects were assessed by exposing the unique Cd-tolerant and Cd-accumulating pea (Pisum sativum L.) mutant SGECd(t) and its wild-type (WT) line SGE to either cadmium (1, 4 μM CdCl2) or mercury (0.5, 1, 2 μM HgCl2) in hydroponic culture for 12 days. When exposed to Cd, SGECd(t) accumulated more Cd in roots, xylem sap, and shoot, and had considerably more biomass than WT plants. WT plants lost circa 0.2 MPa turgor when grown in 4 μM CdCl2, despite massive decreases in whole-plant transpiration rate and stomatal conductance. In contrast, root Hg accumulation was similar in both genotypes, but WT plants accumulated more Hg in leaves and had a higher stomatal conductance, and root and shoot biomass compared with SGECd(t). Shoot excision resulted in greater root-pressure induced xylem exudation of SGECd(t) in the absence of Cd or Hg and following Cd exposure, whereas the opposite response or no genotypic differences occurred following Hg exposure. Exposing plants that had not been treated with metal to 50 μM CdCl2 for 1h increased root xylem exudation of WT, whereas 50 μM HgCl2 inhibited and eliminated genotypic differences in root xylem exudation, suggesting differences between WT and SGECd(t) plants in aquaporin function. Thus, root water transport might be involved in mechanisms of increased tolerance and accumulation of Cd in the SGECd(t) mutant. However, the lack of cross-tolerance to Cd and Hg stress in the mutant indicates metal-specific mechanisms related to plant adaptation.

  1. Factors Influencing Blood Cadmium and Mercury Concentrations in Residents of Agro-Industries along Nam Phong River, Thailand

    Directory of Open Access Journals (Sweden)

    Wannanapa Srathonghon

    2016-07-01

    Full Text Available This cross-sectional analytical study aimed to determine the blood levels of cadmium (B-Cd and mercury (B-Hg and identify the factors influencing heavy metal accumulation in residents of Agro-Industries along the Nam Phong River. Quantitative data were collected, and systematic random sampling was used to obtain 420 samples for questionnaire interview and serum heavy metal testing for B-Cd and B-Hg. Multiple regression analysis was used to identify factors influencing the accumulation of heavy metals in the population and report mean differences, 95% confidence intervals and p-values. The results indicated that B-Cd levels were within the recommended safety limits for human health (5 µg/dL. However, 4.29% of respondents had Hg levels higher than the recommended safety limits for human health (10 µg/dL. Factors influencing Cd levels included sex (mean difference=0.13 µg/L, 95% CI: 0.03-0.24, p-value=0.02 and smoking (mean difference=0.14 µg/L, 95% CI: 0.09-0.19, p-value<0.001. Factors influencing Hg levels included smoking (mean difference=1.06 µg/L, 95% CI: 0.52-1.61, p-value<0.001, fish consumption (mean difference=1.11 µg/L, 95% CI: 0.22-2.01, p-value=0.01 and river snail consumption (mean difference=0.56 µg/L, 95% CI: 0.03-0.19, p-value=0.03.

  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. 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.

  4. The role of glutathione in mercury tolerance resembles its function under cadmium stress in Arabidopsis.

    Science.gov (United States)

    Sobrino-Plata, Juan; Carrasco-Gil, Sandra; Abadía, Javier; Escobar, Carolina; Álvarez-Fernández, Ana; Hernández, Luis E

    2014-02-01

    Recent research efforts have highlighted the importance of glutathione (GSH) as a key antioxidant metabolite for metal tolerance in plants. Little is known about the mechanisms involved in stress due to mercury (Hg), one of the most hazardous metals to the environment and human health. To understand the implication of GSH metabolism for Hg tolerance, we used two γ-glutamylcysteine synthetase (γECS) Arabidopsis thaliana allele mutants (rax1-1 and cad2-1) and a phytochelatin synthase (PCS) mutant (cad1-3). The leaves of these mutants and of wild type (Col-0) were infiltrated with a solution containing Cd or Hg (0, 3 and 30 μM) and incubated for 24 and 48 h. The formation of phytochelatins (PCs) in the leaf extracts was followed by two different HPLC-based methods and occurred in Col-0, cad2-1 and rax1-1 plants exposed to Cd, whereas in the Hg treatments, PCs accumulated mainly in Col-0 and rax1-1, where Hg-PC complexes were also detected. ASA and GSH/GSSG levels increased under moderate metal stress conditions, accompanied by increased GSH reductase (GR) activity and expression. However, higher metal doses led to a decrease in the analysed parameters, and stronger toxic effects appeared with 30 μM Hg. The GSH concentration was significantly higher in rax1-1 (70% of Col-0) than in cad2-1 (40% of Col-0). The leaves of rax1-1 were less sensitive than cad2-1, in accordance with the greater expression of γECS in rax1-1. Our results underline the existence of a minimal GSH concentration threshold needed to minimise the toxic effects exerted by Hg.

  5. Bioaccumulation of lead, mercury, and cadmium in the greater white-toothed shrew, Crocidura russula, from the Ebro Delta (NE Spain); Sex- and age-dependent variation

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Chardi, Alejandro [Departament de Biologia Animal (Vertebrats), Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 645, 08028 Barcelona (Spain)]. E-mail: a.sanchez.chardi@ub.edu; Lopez-Fuster, Maria Jose [Departament de Biologia Animal (Vertebrats), Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 645, 08028 Barcelona (Spain); Nadal, Jacint [Departament de Biologia Animal (Vertebrats), Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 645, 08028 Barcelona (Spain)

    2007-01-15

    We quantified bioaccumulation of lead, mercury, and cadmium in bones from 105 greater white-toothed shrews (Crocidura russula) collected at the Ebro Delta, a polluted area, and the Medas Islands, a control site. Lead and mercury levels varied with site, age, and sex, although statistical significances depended on each factor. Globally, shrews from the polluted area exhibited significantly higher concentrations of Pb and Hg. Increment of Pb with age was particularly remarkable in wetland animals and was interpreted in relation to human activities, namely hunting. Unlike males, females from the Ebro Delta maintained low Hg levels, which were associated with gestation and lactation. Cadmium levels did not differ between sites, sexes, or ages. This study provides the first data on heavy metals in mammals from this wetland and suggests that C. russula is a good bioindicator of metal pollution. We concluded that sex and age may represent an important source of variation in the bioaccumulation of these metals in wild populations. - Bioaccumulation patterns of Pb and Hg reveal sex and age-related differences in the large bones of the greater white-toothed shrew from a polluted Mediterranean wetland.

  6. Shotgun proteomic analysis unveils survival and detoxification strategies by Caulobacter crescentus during exposure to uranium, chromium, and cadmium.

    Science.gov (United States)

    Yung, Mimi C; Ma, Jincai; Salemi, Michelle R; Phinney, Brett S; Bowman, Grant R; Jiao, Yongqin

    2014-04-01

    The ubiquitous bacterium Caulobacter crescentus holds promise to be used in bioremediation applications due to its ability to mineralize U(VI) under aerobic conditions. Here, cell free extracts of C. crescentus grown in the presence of uranyl nitrate [U(VI)], potassium chromate [Cr(VI)], or cadmium sulfate [Cd(II)] were used for label-free proteomic analysis. Proteins involved in two-component signaling and amino acid metabolism were up-regulated in response to all three metals, and proteins involved in aerobic oxidative phosphorylation and chemotaxis were down-regulated under these conditions. Clustering analysis of proteomic enrichment revealed that the three metals also induce distinct patterns of up- or down-regulated expression among different functional classes of proteins. Under U(VI) exposure, a phytase enzyme and an ABC transporter were up-regulated. Heat shock and outer membrane responses were found associated with Cr(VI), while efflux pumps and oxidative stress proteins were up-regulated with Cd(II). Experimental validations were performed on select proteins. We found that a phytase plays a role in U(VI) and Cr(VI) resistance and detoxification and that a Cd(II)-specific transporter confers Cd(II) resistance. Interestingly, analysis of promoter regions in genes associated with differentially expressed proteins suggests that U(VI) exposure affects cell cycle progression.

  7. Mercury- and cadmium-assisted [2 + 2] cyclodimerization of tert-butylselenium diimide.

    Science.gov (United States)

    Karhu, Aino J; Rautiainen, J Mikko; Oilunkaniemi, Raija; Chivers, Tristram; Laitinen, Risto S

    2015-10-01

    identified by X-ray crystallography as a heptanuclear cluster with selenium(II) diamide ligands N,N'-chelated to the cadmium centers.

  8. Cadmium, mercury and lead in the blood of urban women in Croatia, the Czech Republic, Poland, Slovakia, Slovenia, Sweden, China, Ecuador and Morocco

    Directory of Open Access Journals (Sweden)

    Natalia Pawlas

    2013-02-01

    Full Text Available Objectives: The aim of the study was to make an international comparison of blood levels of cadmium (B-Cd, lead (BPb and mercury (B-Hg of women in seven European, and three non-European cities, and to identify determinants. Materials and Methods: About 50 women (age: 46–62 from each city were recruited (totally 480 in 2006–2009. Interview and questionnaire data were obtained. Blood samples were analysed in one laboratory to avoid interlaboratory variation. Results: Between the European cities, the B-Pb and B-Cd results vary little (range of geometric means: 13.5–27.0 μg/l and 0.25–0.65 μg/l, respectively; the variation of B-Hg was larger (0.40–1.38 μg/l. Between the non-European cities the results for B-Pb, B-Cd and B-Hg were 19.2–68.0, 0.39–0.99 and 1.01–2.73 μg/l, respectively. Smoking was a statistically signifi cant determinant for B-Cd, while fi sh and shellfi sh intakes contributed to B-Hg and B-Pb, amalgam fi llings also contributed to B-Hg. Conclusions: The present results confi rm the previous results from children; the exposure to lead and cadmium varies only little between different European cities suggesting that other factors than the living area are more important. The study also confi rms the previous fi ndings of higher cadmium and lead levels in some non-European cities. The geographical variation for mercury is signifi cant.

  9. Effects of Single and Combinative Pollutions of Lead, Cadmium and Chromium on the Germination of Brassica chinensis L.%铅、镉、铬单一和复合污染对青菜种子萌发的生物学效应

    Institute of Scientific and Technical Information of China (English)

    任安芝; 高玉葆

    2000-01-01

    Germiantion of Bra.s.sica chinensis L. grown in the solution with different concentrations of lead, cadmium and chromium (single and combinative) was investigated. Root lengths decreased with the increase of lead, cadmium and chromium in hydroponic solution. The physiological toxicity order for these three ions was Cr6+>Cd2+>Pb2 +. The uptake of Pb by Bras.sica chinensis was enhanced with Pb addition. The toxicity of Cr and Pb was reduced due to precipitation of Cr2O72- and Pb2+ .The toxicity of Cd to plant decreased when Cr6+ was added.

  10. Size and temperature dependence of the photoluminescence properties of NIR emitting ternary alloyed mercury cadmium telluride quantum dots

    Science.gov (United States)

    Jagtap, Amardeep M.; Chatterjee, Abhijit; Banerjee, Arup; Babu Pendyala, Naresh; Koteswara Rao, K. S. R.

    2016-04-01

    Exciton-phonon coupling and nonradiative relaxation processes have been investigated in near-infrared (NIR) emitting ternary alloyed mercury cadmium telluride (CdHgTe) quantum dots. Organically capped CdHgTe nanocrystals of sizes varying from 2.5-4.2 nm have been synthesized where emission is in the NIR region of 650-855 nm. Temperature-dependent (15-300 K) photoluminescence (PL) and the decay dynamics of PL at 300 K have been studied to understand the photophysical properties. The PL decay kinetics shows the transition from triexponential to biexponential on increasing the size of the quantom dots (QDs), informing the change in the distribution of the emitting states. The energy gap is found to be following the Varshni relation with a temperature coefficient of 2.1-2.8  ×  10-4 eV K-1. The strength of the electron-phonon coupling, which is reflected in the Huang and Rhys factor S, is found in the range of 1.17-1.68 for QDs with a size of 2.5-4.2 nm. The integrated PL intensity is nearly constant until 50 K, and slowly decreases up to 140 K, beyond which it decreases at a faster rate. The mechanism for PL quenching with temperature is attributed to the presence of nonradiative relaxation channels, where the excited carriers are thermally stimulated to the surface defect/trap states. At temperatures of different region (<140 K and 140-300 K), traps of low (13-25 meV) and high (65-140 meV) activation energies seem to be controlling the quenching of the PL emission. The broadening of emission linewidth is found to due to exciton-acoustic phonon scattering and exciton-longitudinal optical (LO) phonon coupling. The exciton-acoustic phonon scattering coefficient is found to be enhanced up to 55 μeV K-1 due to a stronger confinement effect. These findings give insight into understanding the photophysical properties of CdHgTe QDs and pave the way for their possible applications in the fields of NIR photodetectors and other optoelectronic devices.

  11. Human exposure to lead, cadmium and mercury through fish and seafood product consumption in Italy: a pilot evaluation.

    Science.gov (United States)

    Pastorelli, A A; Baldini, M; Stacchini, P; Baldini, G; Morelli, S; Sagratella, E; Zaza, S; Ciardullo, S

    2012-01-01

    The presence of selected toxic heavy metals, such as cadmium (Cd), lead (Pb) and mercury (Hg), was investigated in fish and seafood products, namely, blue mussel, carpet shell clam, European squid, veined squid, deep-water rose shrimp, red mullet, European seabass, gilthead seabream, Atlantic cod, European hake, Atlantic bluefin tuna and swordfish so as to assess their human exposure through diet. Metals were detected by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and hydride generation atomic absorption spectrometry (Hg-AAS). Measurements of Cd, Pb and Hg were performed by means of analytical methods validated in compliance with UNI CEI EN ISO/IEC 17025 [2005. General requirements for the competence of testing and calibration laboratories. Milano (Italy): UNI Ente Nazionale Italiano di Unificazione]. The exposure assessment was undertaken matching the levels of Cd, Pb and total Hg with consumption data related to fish and seafood products selected for this purpose. In order to establish human health implications, the estimated weekly intakes (EWIs) for Cd, Pb and Hg were compared with the standard tolerable weekly intakes (TWI) for Cd and provisional tolerable weekly intakes (PTWIs) for Pb and Hg stipulated by the European Food Safety Authority (EFSA) and the Food and Agriculture Organization/World Health Organization (FAO/WHO) Joint Expert Committee on Food Additives (JECFA). The found metal concentrations were largely below the maximum levels (MLs) established at the European Union level with the exception of Cd. This metal exceeded the MLs in squid, red mullet, European hake and Atlantic cod. Squid and blue mussel showed the highest Pb concentrations which accounted for 60% and 10% of the MLs, respectively. Highest Hg levels were found in predatory fish. The concentrations of Hg in swordfish, Atlantic bluefin tuna and red mullet accounted for 50%, 30% and 30% of the MLs, respectively. The EWIs for Cd, Pb and Hg related to the consumption

  12. Comparative analysis of concentrations of lead, cadmium and mercury in cord blood, maternal blood, and breast milk, as well as persistent chlorinated hydrocarbons in maternal milk samples from Germany and Iran; Vergleichende Untersuchungen ueber die Blei-, Cadmium- und Quecksilberkonzentrationen im Nabelschnurblut, im muetterlichen Blut und in der Frauenmilch sowie ueber einige persistente Organochlorverbindungen in der Milch deutscher und iranischer Muetter

    Energy Technology Data Exchange (ETDEWEB)

    Javanmardi, F.

    2001-07-01

    The concentration of the heavy metals lead, cadmium and mercury in cord blood, maternal blood and breast milk has been studied. Lead and cadmium were analyzed by atomic absorption spectrometry. Mercury was determined using the flow-injection hydride technique. According to the concentrations of heavy metals and chlorinated hydrocarbons we ascertained for the region of Rendsburg, the toxic risk for infants relative to the consumption of contaminated maternal milk can be viewed as very slight. (orig.) [German] Ziel der Arbeit war es, die aktuelle Schwermetallbelastung des Nabelschnurblutes, des muetterlichen Blutes und der Muttermilch zu untersuchen. Die Bestimmung von Blei und Cadmium erfolgte mit Hilfe der Atomabsorptionsspektrometrie. Quecksilber wurde mittels der Fliessinjektions-Hydridtechnik bestimmt. Nach den von uns ermittelten Schwermetall- bzw. Chlorkohlenwasserstoffkonzentrationen fuer die Region Rendsburg kann das mit dem Verzehr kontaminierter Muttermilch verbundene toxische Risiko fuer den Saeugling als sehr gering eingeschaetzt werden. (orig.)

  13. Optimization of process conditions for removal of cadmium using bioactive constituents of Moringa oleifera seeds.

    Science.gov (United States)

    Jamal, P; Muyibi, S A; Syarif, W M

    2008-07-01

    Pollutants, especially heavy metals like cadmium, Chromium, lead and mercury, play a significant role in causing various water-borne diseases to humans. This study evaluates the sorption properties of bioactive constituents of Moringa oleifera seeds for decontamination of cadmium at laboratory scale. The performance of the bioactive constituent extracted by salt extraction method was enhanced by process optimization with various concentration of bioactive dosages, agitation speed, contact time, pH and heavy metal concentrations. Statistical optimization was carried out for evaluating the polynomial regression model through effect of linear, quadratic and interaction of the factors. The maximum removal of cadmium was 72% by using 0.2 g/l of bioactive dosage.

  14. Canadian House Dust Study: Population-based concentrations, loads and loading rates of arsenic, cadmium, chromium, copper, nickel, lead, and zinc inside urban homes

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Pat E. [Exposure and Biomonitoring Division, Healthy Environments and Consumer Safety Branch, Health Canada, 50 Colombine Driveway, Ottawa, ON, Canada K1A 0K9 (Canada); Department of Earth Sciences, University of Ottawa, 140 Louis Pasteur, Ottawa, ON, Canada K1N 6N5 (Canada); Levesque, Christine [Exposure and Biomonitoring Division, Healthy Environments and Consumer Safety Branch, Health Canada, 50 Colombine Driveway, Ottawa, ON, Canada K1A 0K9 (Canada); Chénier, Marc; Gardner, H. David [Exposure and Biomonitoring Division, Healthy Environments and Consumer Safety Branch, Health Canada, 50 Colombine Driveway, Ottawa, ON, Canada K1A 0K9 (Canada); Department of Earth Sciences, University of Ottawa, 140 Louis Pasteur, Ottawa, ON, Canada K1N 6N5 (Canada); Jones-Otazo, Heather [Regions and Programs Branch, Health Canada, 180 Queen Street West, Toronto, ON, Canada M5V 3L7 (Canada); Petrovic, Sanya [Contaminated Sites Division, Healthy Environments and Consumer Safety Branch, Health Canada, 269 Laurier Ave West, Ottawa, ON, Canada K1A 0K9 (Canada)

    2013-01-15

    The Canadian House Dust Study was designed to obtain nationally representative urban house dust metal concentrations (μg g{sup −1}) and metal loadings (μg m{sup −2}) for arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn). Consistent sampling of active dust of known age and provenance (area sampled) also permitted the calculation of indoor loading rates (mg m{sup −2} day{sup −1} for dust and μg m{sup −2} day{sup −1} for metals) for the winter season (from 2007 to 2010) when houses are most tightly sealed. Geomean/median indoor dust loading rates in homes located more than 2 km away from industry of any kind (9.6/9.1 mg m{sup −2} day{sup −1}; n = 580) were significantly lower (p < .001) than geomean (median) dust loading rates in homes located within 2 km of industry (13.5/13.4 mg m{sup −2} day{sup −1}; n = 421). Proximity to industry was characterized by higher indoor metal loading rates (p < .003), but no difference in dust metal concentrations (.29 ≥ p ≤ .97). Comparisons of non-smokers' and smokers' homes in non-industrial zones showed higher metal loading rates (.005 ≥ p ≤ .038) in smokers' homes, but no difference in dust metal concentrations (.15 ≥ p ≤ .97). Relationships between house age and dust metal concentrations were significant for Pb, Cd and Zn (p < .001) but not for the other four metals (.14 ≥ p ≤ .87). All seven metals, however, displayed a significant increase in metal loading rates with house age (p < .001) due to the influence of higher dust loading rates in older homes (p < .001). Relationships between three measures of metals in house dust – concentration, load, and loading rate – in the context of house age, smoking behavior and urban setting consistently show that concentration data is a useful indicator of the presence of metal sources in the home, whereas dust mass is the overriding influence on metal loadings and loading rates

  15. Lactobacillus plantarum L67 glycoprotein protects against cadmium chloride toxicity in RAW 264.7 cells.

    Science.gov (United States)

    Song, Sooyeon; Oh, Sejong; Lim, Kye-Taek

    2016-03-01

    The food and water we consume may be contaminated with a range of chemicals and heavy metals, such as lead, cadmium, arsenic, chromium, and mercury by accumulation through the food chain. Cadmium is known to be one of the major components in cigarette smoke and can cause lesions in many organs. Some lactobacilli can bind and remove heavy metals such as cadmium, lead, and copper. However, the mechanisms of cadmium toxicity and inhibition by probiotics are not clear. In this study, we demonstrated that glycoprotein (18 kDa) isolated from Lactobacillus plantarum L67 protected RAW 264.7 cells from expression of inflammation-related factors stimulated by cadmium chloride (100 µM). Furthermore, we evaluated the cytotoxicity of cadmium using the MTT assay and intracellular Ca(2+) using fluorescence, and assessed activities of activator protein kinase C (PKC-α), inducible nitric oxide synthase, activator protein (AP)-1, and mitogen-activated protein kinases using immunoblot. Our results indicated that glycoprotein isolated from L. plantarum L67 inhibited intracellular Ca(2+) mobilization. It also significantly suppressed inflammatory factors such as AP-1 (c-Jun and c-Fos), mitogen-activated protein kinases (ERK, JNK, and p38), and inducible nitric oxide synthase. Our findings suggest that the 24-kDa glycoprotein isolated from L. plantarum L67 might be used as a food component for protection of inflammation caused by cadmium ion.

  16. Differential fitness of allelic isozymes in the marine gastropods Littorina punctata and Littorina neritoides, exposed to the environmental stress of the combined effects of cadmium and mercury pollution

    Science.gov (United States)

    Lavie, Batia; Nevo, Eviatar

    1987-07-01

    The present study tested the separate and the interactive pollution effects of cadmium and mercury on the electrophoretically detected allelic isozyme frequencies of the enzyme phosphoglucose isomerase for two species of littoral marine gastropods — Littorina punctata and L. neritoides — and the enzyme amino peptidase for L. neritoides. Our results indicate differential survivorship of allelic isozyme genotypes specific for each type of pollutant and for their interaction, as well as trends common to all pollutants. Theoretically the results reflect the adaptive nature of at least some allozymic genotypes in these marine gastropods and seem inconsistent with the neutral theory of allozyme polymorphisms. Practically, the results reinforce earlier conclusions that changes in the frequency of allelic isozymes may be used as a genetic monitor of pollution.

  17. Preventing Soil Mercury and Cadmium into Vegetables by Additives%几种化学物质抑制土壤汞、镉进入蔬菜的研究

    Institute of Scientific and Technical Information of China (English)

    何晶晶; 杨志敏; 王莉玮; 陈宏

    2014-01-01

    采用盆栽试验,研究了高污染背景条件下,添加石灰、腐殖酸、硫化钠、亚硒酸钠抑制紫色土汞、镉进入蔬菜的效果.结果表明,这几种化学物质都能够降低紫色土重金属活性,但考虑产量时宜选用腐殖酸,它既能增产8.29%,又能分别降低蔬菜汞、镉含量的32.35%,18.65%.汞、镉在莴笋各器官的分配与且仅与重金属元素有关,而与化学物质及其添加量无关,汞主要积累于根部,镉则积累于可食茎叶部分.%The pot experiments have been conducted to study the effects of preventing purple soil mercury and cadmium into vegetables by adding lime,humic acid,sodium sulfide and sodium selenite on the back-ground of the serious soil pollution.The results show that,although these additives can decrease the avail-ability of purple soil mercury and cadmium,the humic acid should be applied selectively,because it could not only increase the vegetables’yield by 8.29%,but also decrease the content of mercury and cadmium in vegetables by 32.35% and 18.65% respectively,compared with the controls.The vegetables’mercury and cadmium are mainly accumulated in the root and cadmium in the edible such as stem and leaf.

  18. Levels of lead, arsenic, mercury and cadmium in clays for oral use on the Dutch market and estimation of associated risks.

    Science.gov (United States)

    Reeuwijk, N M; Klerx, W N M; Kooijman, M; Hoogenboom, L A P; Rietjens, I M C M; Martena, M J

    2013-01-01

    Pregnant women in Africa, Asia and Suriname, and some immigrants in Western societies, traditionally consume clay products known by a variety of names such as mabele, calabash chalk, sikor and pimba. Furthermore, clay is used for health purposes in Western societies. Because certain clays can contain high levels of metals and metalloids, the aim of this study was to determine lead, arsenic, mercury and cadmium in clay products for oral use available on the Dutch market. Traditional clays originating from Africa (n = 10) and Suriname (n = 26), and health clays (n = 27) were sampled from 2004 up to and including 2012. Total metal and metalloid contents were measured by ICP-MS and showed maximum levels of lead, arsenic, mercury and cadmium of 99.7, 45.1, 2.2 and 0.75 mg kg⁻¹, respectively. In the absence of maximum limits for these type of clays, the potential exposure was estimated from the determined concentration, the estimated daily use level of the clays, and the estimated bioaccessibility of the different metals and arsenic. The intake estimates were compared with existing health-based guidance values. For lead, the use of 34 of the 36 traditional clays and two of the 27 health clays would result in intake levels exceeding the toxicological limit by up to 20-fold. Use of 15 of the 35 traditional clays and 11 of the 27 health clays would result in intake levels exceeding the toxicological limit for inorganic arsenic by up to 19-fold. Although limited bioaccessibility from the clay may limit the exposure and exceedance of the health-based guidance values, it was concluded that lead and arsenic intakes from some clay products could be of concern also because of their use by pregnant women and the potential developmental toxicity. As a result the use of these products, especially by pregnant women, should be discouraged.

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

    Directory of Open Access Journals (Sweden)

    Jiri Kudr

    2014-12-01

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

  20. Aromatic N-oxides in construction of different carboxylate coordination polymers of zinc(II), cadmium(II) and mercury(II)

    Science.gov (United States)

    Sarma, Rupam; Baruah, Jubaraj B.

    2011-09-01

    The coordination polymers [Zn(C 6H 5COO) 2(PNO)] n ( 1), [Zn 2(C 6H 5COO) 4(4,4'-BPNO)] n ( 2), [Zn 4(C 6H 4C 2O 4) 4(4,4'-BPNO) 2(H 2O) 5] n· nH 2O ( 3), [Cd(C 6H 5COO) 2(PNO)] n ( 4), [Cd 3(C 6H 5COO) 6(4,4'-BPNO) 2] n·2 nH 2O ( 5), [Cd(C 6H 4C 2O 4)(4,4'-BPNO)(H 2O)] n ( 6) and [Hg(C 6H 5COO) 2(4,4'-BPNO) 2] n ( 7), (where PNO = pyridine N-oxide, 4,4'-BPNO = 4,4'-bipyridyl- N,N'-dioxide) are synthesized and structurally characterized. The structures of these coordination polymers exhibit mononuclear to trinuclear nodes built by ligation of carboxylate to metal ions connected by N-oxide ligands. Pyridine N-oxide interconnects metal nodes by acting as μ 2-bridging ligand in complexes 1, and 4. In the linear coordination polymer 2, the paddle wheel structure of zinc(II) benzoate units are interconnected by 4,4'-bipyridyl- N,N'-dioxide which acts as a bidentate spacer ligand adopting a trans μ 2-η 1 : η 1 coordination mode. The polymeric structure of 3 formed by terephthalate and 4,4'-bipyridyl- N,N'-dioxide with zinc(II) contains self-assembled dinuclear Zn 2O 2 type of carboxylate cores, with 4,4'-bipyridyl- N,N'-dioxide coordinating through cis μ 2-η 1 : η 1 coordination mode. The cadmium coordination polymer 5, comprising of 4,4'-bipyridyl- N,N'-dioxide and benzoate, has trinuclear cadmium benzoate cores wherein the terminal cadmium ions are interconnected by monodentate 4,4'-bipyridyl- N,N'-dioxide bridges. The coordination polymer 6 comprises of mononuclear cadmium nodes independently bridged by terephthalate and 4,4'-bipyridyl- N,N'-dioxide thereby leading to a 3-fold interpenetrated three dimensional network. Double helical polymeric structure is observed in the coordination polymer 7 derived from mononuclear mercury(II) benzoate nodes bridged by 4,4'-bipyridyl- N,N'-dioxide with cis μ 2-η 1 : η 1 coordination mode.

  1. The Danish contribution to the European DEMOCOPHES project: A description of cadmium, cotinine and mercury levels in Danish mother-child pairs and the perspectives of supplementary sampling and measurements

    Energy Technology Data Exchange (ETDEWEB)

    Mørck, Thit A. [Department of Public Health, University of Copenhagen, Copenhagen (Denmark); Nielsen, Flemming [Department of Public Health, University of Southern Denmark, Odense (Denmark); Nielsen, Jeanette K.S.; Jensen, Janne F.; Hansen, Pernille W.; Hansen, Anne K.; Christoffersen, Lea N. [Department of Public Health, University of Copenhagen, Copenhagen (Denmark); Siersma, Volkert D. [The Research Unit for General Practice and Section of General Practice, Department of Public Health, University of Copenhagen, Copenhagen (Denmark); Larsen, Ida H.; Hohlmann, Linette K. [Department of Public Health, University of Copenhagen, Copenhagen (Denmark); Skaanild, Mette T. [Danish Environmental Protection Agency (Denmark); Frederiksen, Hanne [Department of Growth and Reproduction, University Hospital, Copenhagen (Denmark); Biot, Pierre [Federal Public Service Health, Food Chain Safety and Environment, Brussels (Belgium); Casteleyn, Ludwine [University of Leuven, Leuven (Belgium); Kolossa-Gehring, Marike; Schwedler, Gerda [Federal Environment Agency (UBA), Berlin (Germany); Castaño, Argelia [Instituto de Salud Carlos III (ISCIII), Majadahonda, Madrid (Spain); Angerer, Jürgen; Koch, Holger M. [Institute for Prevention and Occupational Medicine of the German social Accident Insurance, Institute of the Ruhr-Universität Bochum (IPA), Bochum (Germany); Esteban, Marta [Instituto de Salud Carlos III (ISCIII), Majadahonda, Madrid (Spain); and others

    2015-08-15

    Human biomonitoring (HBM) is an important tool, increasingly used for measuring true levels of the body burdens of environmental chemicals in the general population. In Europe, a harmonized HBM program was needed to open the possibility to compare levels across borders. To explore the prospect of a harmonized European HBM project, DEMOCOPHES (DEMOnstration of a study to COordinate and Perform Human biomonitoring on a European Scale) was completed in 17 European countries. The basic measurements performed in all implemented countries of DEMOCOPHES included cadmium, cotinine and phthalate metabolites in urine and mercury in hair. In the Danish participants, significant correlations between mothers and children for mercury in hair and cotinine in urine were found. Mercury in hair was further significantly associated with intake of fish and area of residence. Cadmium was positively associated with BMI in mothers and an association between cadmium and cotinine was also found. As expected high cotinine levels were found in smoking mothers. For both mercury and cadmium significantly higher concentrations were found in the mothers compared to their children. In Denmark, the DEMOCOPHES project was co-financed by the Danish ministries of health, environment and food safety. The co-financing ministries agreed to finance a number of supplementary measurements of substances of current toxicological, public and regulatory interest. This also included blood sampling from the participants. The collected urine and blood samples were analyzed for a range of other persistent and non-persistent environmental chemicals as well as two biomarkers of effect. The variety of supplementary measurements gives the researchers further information on the exposure status of the participants and creates a basis for valuable knowledge on the pattern of exposure to various chemicals. - Highlights: • Levels of cadmium, mercury and cotinine in the Danish subpopulation are comparable to levels in the

  2. Cuantificación de plomo, cadmio y cromo mediante sialoquímica Quantification of lead, cadmium and chromium through sialochemistry

    Directory of Open Access Journals (Sweden)

    MIREYA GONZÁLEZ

    1997-05-01

    Full Text Available Objetivo. Determinar las concentraciones de plomo, cadmio y cromo, y establecer su posible asociación con diferentes factores sociodemográficos. Material y métodos. Se seleccionó una muestra representativa de 100 estudiantes de posgrado de la Facultad de Odontología de la Universidad Nacional Autónoma de México (UNAM, a los cuales se les colectó saliva total no estimulada. Dichas muestras fueron analizadas por espectrofotometría de absorción atómica con horno de grafito. Resultados. Metales pesados como el plomo, el cadmio y el cromo se encuentran en concentraciones mucho más altas que las informadas en la literatura: Pb, = 3.10 m g/dL-1, máxima: 16.8 my g/dL-1, y mínima: 0.04 my g/dL-1; Cd, = 0.25 my g/dL-1, máxima: 2.04 my g/dL-1, y mínima: 0.004 my g/dL-1; y Cr, = 1.43 my g/dL-1, máxima: 4.82 my g/dL-1, y mínima: 0.05 my g/dL-1. Asimismo, variables como la zona de residencia, el sexo, la edad y la ingesta de comida enlatada no influyen en los niveles de plomo y cromo. Sin embargo, en el caso del cadmio y la edad existe una asociación inversa (ji²= 5.9012, pObjective. To determine the concentration of lead (Pb, cadmium (Cd, and chromium (Cr and establish the possible association of these heavy metals with some sociodemographic factors. Material and methods. A representative sample of one hundred dental students from the National Autonomous University of Mexico living in Mexico City participated in this study. Unstimulated human whole saliva samples were analyzed by Atomic Absorption Spectroscopy. Results. Concentrations of Pb, Cd, and Cr were higher than those reported elsewhere: Pb ( or = 3.10 m g/dL-1; Maximum: 16.8 mu g/dL-1 and Minimum: 0.04 mu g/dL-1, Cd ( or = 0.25 mu g/dL-1; Maximum: 2.04 mu g/dL-1 and Minimum: 0.004 mu g/dL-1 and Cr ( or = 1.43 mu g/dL-1; Maximum: 4.82 mu g/dL-1 and Minimum: 0.05 mu g/dL-1. No association was found between the variables studied (age, sex, geographic area and canned food consumption

  3. Contamination levels of mercury and cadmium in melon-headed whales (Peponocephala electra) from a mass stranding on the Japanese coast

    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; Hisamichi, Yohsuke; Kimura, Osamu [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); Baker, C. Scott [Marine Mammal Institute and Department of Fisheries and Wildlife, Oregon State University, Newport, Oregon 97365 (United States)

    2008-08-15

    Total mercury (T-Hg), methyl mercury (M-Hg), cadmium (Cd), selenium (Se), zinc (Zn) and copper (Cu) concentrations in the organs of melon-headed whales from a mass stranding on the Japanese coast were analyzed. The mean concentration of T-Hg in the liver (126 {+-} 97 {mu}g/wet g, n = 13) was markedly higher than those in kidney (6.34 {+-} 2.36 {mu}g/wet g, n = 12) and muscle (4.90 {+-} 2.33 {mu}g/wet g, n = 15). In contrast, the mean concentration of M-Hg in the liver (9.08 {+-} 2.24 {mu}g/wet g) was similar to those in the kidney (3.47 {+-} 0.91 {mu}g/wet g) and muscle (3.78 {+-} 1.53 {mu}g/wet g). The mean percentage of M-Hg in the T-Hg found in the liver (13.1 {+-} 10.3) was significantly lower than those in the kidney (58.3 {+-} 15.0) and muscle (78.9 {+-} 8.4). The molar ratio of T-Hg to Se in the liver was effectively 1.0, but those in the kidney and muscle were markedly lower. Conversely, the mean concentration of Cd was markedly higher in the kidney (24.4 {+-} 7.4 {mu}g/wet g) than in the liver (7.24 {+-} 2.08 {mu}g/wet g) and muscle (less than 0.05 {mu}g/wet g). These results suggest that the formation of Hg-Se compounds mainly occurs in the liver after the demethylation of M-Hg, and Cd preferentially accumulates in the kidney of melon-headed whales.

  4. Chromium, lead and cadmium in Danish milk products and cheese determined by Zeeman graphite furnace atomic absorption spectrometry after direct injection or pressurised ashing

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Rasmussen, L.

    1991-01-01

    -degrees-C and then further ashed at 1 100-degrees-C with argon as the purge gas. Zeeman background correction was used in the atomisation step at 2 300-degrees-C. The detection limit was 0.7 ng/g. Direct detection of chromium in milk, using only argon as purge gas, was inferior. Non-homogeneous and solid...

  5. Evaluation of the Content of Lead, Cadmium, Mercury, Arsenic, Tin, Copper and Zinc during the Production Process Flow of Tomato Broth

    Directory of Open Access Journals (Sweden)

    Corina Andrei

    2013-11-01

    Full Text Available Heavy metals are among the largest contaminants of food products. Once metals are present in vegetables, their concentrations are rarely modified by industrial processing techniques, although in some cases washing may decrease the metal content. The main objective of this study was to quantify the effect of industrial processing on the content of lead, cadmium, mercury, arsenic, tin, copper and zinc in tomatoes and products resulting on flow technology of tomato broth. For the determination of essential elements and/or potentially toxic was use atomic absorption spectrometry. The analytical results for quantitative evaluation the concentrations of the investigated elements on the samples of tomatoes taken from the technological process of the production of tomato broth indicated the presence of Pb, Cd, Cu and Zn but with a level of concentration that significantly decreased in the finished product and the absence of metals Hg and As in all investigated samples. Effect of industrial processing on the content of tin in tomato samples analyzed was characterized by fluctuations in the residual content that led to a significant increase in concentration of 0.100 ± 0.041 mg kg-1 (tomatoes - unprocessed to 0.200 ± 0.041 mg kg-1 (tomato broth.

  6. Rapid long-wave infrared laser-induced breakdown spectroscopy measurements using a mercury-cadmium-telluride linear array detection system.

    Science.gov (United States)

    Yang, Clayton S-C; Brown, Eiei; Kumi-Barimah, Eric; Hommerich, Uwe; Jin, Feng; Jia, Yingqing; Trivedi, Sudhir; D'souza, Arvind I; Decuir, Eric A; Wijewarnasuriya, Priyalal S; Samuels, Alan C

    2015-11-20

    In this work, we develop a mercury-cadmium-telluride linear array detection system that is capable of rapidly capturing (∼1-5  s) a broad spectrum of atomic and molecular laser-induced breakdown spectroscopy (LIBS) emissions in the long-wave infrared (LWIR) region (∼5.6-10  μm). Similar to the conventional UV-Vis LIBS, a broadband emission spectrum of condensed phase samples covering the whole 5.6-10 μm region can be acquired from just a single laser-induced microplasma or averaging a few single laser-induced microplasmas. Atomic and molecular signature emission spectra of solid inorganic and organic tablets and thin liquid films deposited on a rough asphalt surface are observed. This setup is capable of rapidly probing samples "as is" without the need of elaborate sample preparation and also offers the possibility of a simultaneous UV-Vis and LWIR LIBS measurement.

  7. Exposure to Nickel, Chromium, or Cadmium Causes Distinct Changes in the Gene Expression Patterns of a Rat Liver Derived Cell Line

    Science.gov (United States)

    2011-11-16

    and pigments and is responsible for 500,000 industrial exposures in the United States [4,5]. Exposure to cadmium can occur as a result of mining...antioxidative/electrophilic response on the liver. Toxicol Appl Pharmacol 244: 57-65. 19. Ryter SW, Choi AM (2009) Heme oxygenase-1/carbon monoxide

  8. Mercury and Air Toxic Element Impacts of Coal Combustion By-Product Disposal and Utilizaton

    Energy Technology Data Exchange (ETDEWEB)

    David Hassett; Loreal Heebink; Debra Pflughoeft-Hassett; Tera Buckley; Erick Zacher; Mei Xin; Mae Sexauer Gustin; Rob Jung

    2007-03-31

    The University of North Dakota Energy & Environmental Research Center (EERC) conducted a multiyear study to evaluate the impact of mercury and other air toxic elements (ATEs) on the management of coal combustion by-products (CCBs). The ATEs evaluated in this project were arsenic, cadmium, chromium, lead, nickel, and selenium. The study included laboratory tasks to develop measurement techniques for mercury and ATE releases, sample characterization, and release experiments. A field task was also performed to measure mercury releases at a field site. Samples of fly ash and flue gas desulfurization (FGD) materials were collected preferentially from full-scale coal-fired power plants operating both without and with mercury control technologies in place. In some cases, samples from pilot- and bench-scale emission control tests were included in the laboratory studies. Several sets of 'paired' baseline and test fly ash and FGD materials collected during full-scale mercury emission control tests were also included in laboratory evaluations. Samples from mercury emission control tests all contained activated carbon (AC) and some also incorporated a sorbent-enhancing agent (EA). Laboratory release experiments focused on measuring releases of mercury under conditions designed to simulate CCB exposure to water, ambient-temperature air, elevated temperatures, and microbes in both wet and dry conditions. Results of laboratory evaluations indicated that: (1) Mercury and sometimes selenium are collected with AC used for mercury emission control and, therefore, present at higher concentrations than samples collected without mercury emission controls present. (2) Mercury is stable on CCBs collected from systems both without and with mercury emission controls present under most conditions tested, with the exception of vapor-phase releases of mercury exposed to elevated temperatures. (3) The presence of carbon either from added AC or from unburned coal can result in mercury

  9. Effects of Potash Fertilizer on Cabbage' s Quality in CadmiumPolluted Soils

    Directory of Open Access Journals (Sweden)

    WANG Xiao-jing

    2015-02-01

    protein. The concentration of heavy metal cadmium and arsenic significantly increased, but lead, chromium and mercury universally decreased in cadmium stress. From this study we found that application of potash fertilizer could effectively improve the quality of cabbage, especially decrease the concentration of various heavy metals in cabbage' s leaves and the recommended dosage was 200~ 400 mg·kg-1 in low cadmium stress and 400~600 mg·kg-1 in high cadmium stress.

  10. Supercritical Fluid Extraction of Metals Using Bis(2,4,4-trimethyl-pentylmonothiophosphinic Acid as Chelating Agent for Subsequent ICP-MS Analyses of Mercury, Cadmium and Lead in Sediment

    Directory of Open Access Journals (Sweden)

    E. C. Roa

    2011-01-01

    Full Text Available This study investigated and validated the optimum conditions for a supercritical fluid extraction (SFE method using bis(2,4,4-trimethylpentyl-monothiophosphinic acid as a chelating ligand, for subsequent ICP-MS analyses of mercury, cadmium and lead in sediment. Several combinations of pressure, temperature and modifier (P-T-M conditions for SFE were tested and an appropriate collection solvent was also determined using a sediment certified reference material (CRM as sample, to determine the optimum set of conditions. Validation results of the optimized method indicated high percent recoveries which are better compared to standard methods.

  11. Lead and other heavy metals (cadmium and mercury accumulation in bivalve mollusks (Mytilus galloprovincialis, Ruditapes spp. and Crassostrea gigas sampled in Sardinia in 2008-2012

    Directory of Open Access Journals (Sweden)

    Pierluigi Piras

    2013-12-01

    Full Text Available The Sardinian shellfish farming, like the national, is mainly focused on mussels and carpet-shell clams, still less on cupped oyster farming. After Olbia’s Gulf, various lagoon areas along the coastal perimeter have been interested to shellfish farming. They are transitional waters, whose state of pollution must be evaluated both as ecosystem’s health and as directly/indirectly human risk. This also applies to heavy metals such as lead, cadmium and mercury, arising both from anthropogenic that geological-natural activity. The aim of the present study is to investigate the variability of the concentrations of these metals in different mollusks to make a comparative assessment, detect trends (over the five-years or cyclicrecurring and identify hot spots. In 2008- 2012, 984 samples have been analysed by inductively coupled plasma mass spectrometry technique. Of them, 599 in pre-marketing (for classification of production areas or their monitoring and the remaining during marketing. The difference between the average levels of the three metals in the different mollusks species was statistically significant, with Pb>Cd>Hg, and there was evidence of a gradual downward trend, albeit moderate, in the contamination levels, with a significant seasonality in concentrations levels, of lead in particular. Also comparisons between the bio-monitored coastal areas were statistically different. Since the samples were representative of the entire production of bivalve mollusks in Sardinia and the contamination allowable limits have never been exceeded in the products marketed, it can be concluded that these products are safe, pointing out that maintenance of monitoring/surveillance plans provides useful information species-dependent, site-specific and temporal trends.

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

    Energy Technology Data Exchange (ETDEWEB)

    Naidu, J.R.

    1974-06-01

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

  13. Effects of Water-Borne Mercury and Cadmium Exposure on Lipid Peroxidation and Antioxidant Enzymes in Mangrove Red Snapper Lutjanus argentimaculatus

    Directory of Open Access Journals (Sweden)

    Xue-Feng Wang

    2013-08-01

    Full Text Available Effects of waterborne cadmium (Cd2+ and mercury (Hg2+ both separately and in combination on the lipid peroxidation and antioxidant activity in Lutjanus argentimaculatus was investigated. The fish was exposed for 3, 7 and 15 days respectively to Cd2+, Hg2+ and the mixture of both. Exposure to Cd2+ was done at three different concentrations viz 1, 5 and 100 μg/L .The fish was exposed to Hg2+ at 0.2,0.5 and 10 μg/L. Further L. argentimaculatus was also exposed to a mixture containing 5 μg/L Cd2+ and 0.5 μg/L Hg2+. The results showed increased levels of antioxidant enzymes such as Superoxide Dismutase (SOD, Catalase (CAT and Peroxidase (POD (p<0.05 both in hepatic and branchial tissues. The level of Malonialdehyde (MDA which is an indicator of lipid peroxidation also showed significant increase (p<0.05. Further, antioxidant enzymes and MDA could not fall down to normal levels even after 15 days of release to clean sea water in all the treatments tested. However, the activity of antioxidant enzymes in the fishes exposed to mixture containing both Cd2+ and Hg2+ did not showed remarkable raise as when treated separately. The study indicated that the increase of antioxidant enzymes activity and MDA need to be considered carefully as pollution indicators as their values do not conform well to the corresponding metal ion concentrations, in view of co-effects of metals.

  14. Thin film cadmium telluride, zinc telluride, and mercury zinc telluride solar cells. Final subcontract report, 1 July 1988--31 December 1991

    Energy Technology Data Exchange (ETDEWEB)

    Chu, T.L. [University of South Florida, Tampa, FL (United States)

    1992-04-01

    This report describes research to demonstrate (1) thin film cadmium telluride solar cells with a quantum efficiency of 75% or higher at 0. 44 {mu}m and a photovoltaic efficiency of 11.5% or greater, and (2) thin film zinc telluride and mercury zinc telluride solar cells with a transparency to sub-band-gap radiation of 65% and a photovoltaic conversion efficiency of 5% and 8%, respectively. Work was directed at (1) depositing transparent conducting semiconductor films by solution growth and metal-organic chemical vapor deposition (MOCVD) technique, (2) depositing CdTe films by close-spaced sublimation (CSS) and MOCVD techniques, (3) preparing and evaluating thin film CdTe solar cells, and (4) preparing and characterizing thin film ZnTe, CD{sub 1-x}Zn{sub 1-x}Te, and Hg{sub 1-x}Zn{sub x}Te solar cells. The deposition of CdS films from aqueous solutions was investigated in detail, and their crystallographic, optical, and electrical properties were characterized. CdTe films were deposited from DMCd and DIPTe at 400{degrees}C using TEGa and AsH{sub 3} as dopants. CdTe films deposited by CSS had significantly better microstructures than those deposited by MOCVD. Deep energy states in CdTe films deposited by CSS and MOCVD were investigated. Thin films of ZnTe, Cd{sub 1- x}Zn{sub x}Te, and Hg{sub 1-x}Zn{sub x}Te were deposited by MOCVD, and their crystallographic, optical, and electrical properties were characterized. 67 refs.

  15. Ecologically acceptable manufacture of rechargeable nickel-hydride-button-cells and lithium-primary-button-cells as an alternative to nickel-cadmium-button-cells, mercury-button-cells and other mercury based alkaline-primary-button-cells. Final report; Investitionen zur Verminderung von Umweltbelastungen. Umweltschonende Herstellung von wiederaufladbaren Nickel-Metall-Hydrid-Knopfzellen und Lithium-Primaer-Knopfzellen zur Substitution von Nickel-Cadmium-Knopfzellen, Quecksilberoxid-Knopfzellen und anderen quecksilberhaltigen alkalischen Primaer-Knopfzellen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Fahlbusch, E.

    1999-06-01

    Resulting from the transfer of the button cell production from Singapore to Ellwangen, it has been possible to develop two completely new button cell production technologies for integration in the Ellwangen plant. The first innovation pertains to the production of rechargeable nickel-bydride-button-cells (NiMH) which replaces entirely the former nickel-cadmium-button-cell production, reducing the cadmium requirements by approximately 86 tons per year and avoiding a further 39 tons of cadmium polluted waste. Secondly, an innovative method for the production of lithium-primary-button-cells (LiP) was developed. LiP-button-cells and zinc/air-button-cells replace the former mercury-button-cell production completely and saving a further 10 tons of mercury yearly. (orig.) [German] Im Rahmen der Verlagerung der Knopfzellenproduktion von Singapur nach Ellwangen wurden zwei neue, innovative Fertigungsbereiche zur Herstellung von Knopfzellen am Produktionsstandort Ellwangen realisiert. Zum einen handelt es sich um die Produktion von wiederaufladbaren Nickel-Metallhybrid-Knopfzellen (NiMH-Knopfzellen). Durch diese NiMH-Knopfzellen werden die bisher produzierten Nickel-Cadmium-Knopfzellen vollstaendig substituiert. Hierdurch wird der Cadmiumanteil im Produkt um ca. 86 Tonnen pro Jahr reduziert. In der Produktion werden zusaetzlich 39 Tonnen cadmiumhaltige Abfaelle vermieden. Als zweiter neuer Fertigungsbereich wurde die Herstellung von Lithium-Primaer-Knopfzellen (LiP-Knopfzellen) realisiert. LiP-Knopfzellen und Zink-Luft-Knopfzellen ersetzen zu 100% die bisher produzierten Quecksilberoxid-Knopfzellen. Die pro Jahr verarbeitete Quecksilbermenge von ungefaehr 10 Tonnen kann somit zukuenftig entfallen. (orig.)

  16. Determination on Iron, Copper, Chromium, Cadmium, Lead, Nickel and Cobalt in Hair Dye%染发剂中铁、铜、铬、镉、铅、镍和钴等重金属含量测定

    Institute of Scientific and Technical Information of China (English)

    解楠; 顾宇翔; 周泽琳

    2012-01-01

    建立了微波消解前处理,电感耦合等离子发射光谱(ICP-AES)测定染发剂中铁、铜、铬、镉、铅、镍和钴等重金属含量的方法.该方法各元素检出限均为0.05 mg/kg,线性范围0~500 ng/mL,加标回收率86.8%~108.0%,相对标准偏差为0.98%~5.54%.该方法简便、灵敏,结果稳定准确,可以用于染发剂中重金属含量的测定.%An inductively coupled plasma-atomic emission spectrometry (ICP-AES) with samples microwave digestion method for determination of Iron, Copper, Chromium, Cadmium, Lead, Nickel and Cobalt in hair dye was established. The detection limits of all elements were 0.05 mg/kg, the linearity ranged from 0 to 500 ng/mL, and recoveries of samples were in the range of 86. 8%~108. 0%, the RSD of precision is from 0. 98% to 5.54%. It indicates that the method is simple, sensitive, stable and accurate, which can be used for the determination of heavy metal elements in hair dye.

  17. Concentrations of strontium, barium, cadmium, copper, zinc, manganese, chromium, antimony, selenium, and lead in the liver and kidneys of dogs according to age, gender, and the occurrence of chronic kidney disease.

    Science.gov (United States)

    Passlack, Nadine; Mainzer, Barbara; Lahrssen-Wiederholt, Monika; Schafft, Helmut; Palavinskas, Richard; Breithaupt, Angele; Zentek, Jürgen

    2015-01-01

    This study was conducted to measure the concentrations of strontium (Sr), barium (Ba), cadmium (Cd), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), antimony (Sb), selenium (Se), and lead (Pb) in canine liver, renal cortex, and renal medulla, and the association of these concentrations with age, gender, and occurrence of chronic kidney disease (CKD). Tissues from 50 dogs were analyzed using inductively coupled plasma mass spectrometry. Cu, Zn, and Mn levels were highest in the liver followed by the renal cortex and renal medulla. The highest Sr, Cd, and Se concentrations were measured in the renal cortex while lower levels were found in the renal medulla and liver. Female dogs had higher tissue concentrations of Sr (liver and renal medulla), Cd (liver), Zn (liver and renal cortex), Cr (liver, renal cortex, and renal medulla), and Pb (liver) than male animals. Except for Mn and Sb, age-dependent variations were observed for all element concentrations in the canine tissues. Hepatic Cd and Cr concentrations were higher in dogs with CKD. In conclusion, the present results provide new knowledge about the storage of specific elements in canine liver and kidneys, and can be considered important reference data for diagnostic methods and further investigations.

  18. Concentrations of lead, cadmium, mercury and other elements in seeds of Lupinus mutabilis and of other legumes.

    Science.gov (United States)

    Gross, R; Auslitz, J; Schramel, P; Payer, H D

    1987-01-01

    Several species of legumes and varieties of lupins were examined for their heavy metal content in the seeds. Atomic absorption spectrometry was the main analytical tool. Validity and reproducibility of the results was checked by analyzing the same materials at two different laboratories performing the same technique. Additionally, inductively coupled plasma emission spectroscopy was applied. In grains of Lupinus mutabilis which constitute a traditional food in Andean populations, the following contents of heavy metals were determined: 0.10-0.25 microgram/g Cd; 0.5-1.6 microgram/g Pb; 0.10-0.15 microgram/g Hg. Seeds of other legumes contained 0.05-0.35 microgram/g Cd; 0.1-0.2 microgram/g Pb; 0.01-0.04 microgram/g Hg. The high lead content of lupins is easily reduced to one tenth by traditional extraction with boiling water. The mercury content, too, is decreased by this technique. The high manganese content of 1 300-1,400 micrograms/g of Lupinus albus compared to other legumes (25-37 micrograms/g) seems to be characteristic for this species and may be of nutritional significance. The comparison of the heavy metal contents of legume seeds of different origin and variety indicates a complex pattern of environmental and genetic factors that contribute to the specific metal contents of individual harvests. On the level of varieties the environmental factors (climate, soil, geology, agricultural techniques) seem to exhibit more important influences on the specific accumulation of heavy metals than genetic factors. In contrast, on the level of species or genera, the accumulation of heavy metals seems to be dominated by genetic factors rather than by environmental influences.

  19. 宁夏回族自治区食品中铅、镉、汞、铜、铝污染状况分析%Analysis of food contamination by lead, cadmium, mercury, copper and aluminum in Ningxia

    Institute of Scientific and Technical Information of China (English)

    魏秋宁; 晋博烜; 丁亚磊; 陈涛

    2015-01-01

    Objective To investigate the situation of food contamination by lead,cadmium,mercury,copper and aluminum in Ningxia Region.Methods Ten categories of food samples up to 712 copies including dairy,edible mushrooms,eggs,preserved egg,meat,organs,aquatic products,vegetables,grains and pasta from supermarkets of five administrative cities of Ningxia Autonomous Region were selected in 2010.The contents of lead,cadmium and mercury in food were detected in 646 samples of 9 categories of food,and copper content of the 30 meat samples were detected.Aluminum content in 66 samples of flour food was tested.According to the methods of national food safety standards (GB 5009.12-2010) and national food hygiene standards (GB/T 5009.13-2003,GB/ T 5009.15-2003 and GB/T 5009.17-2003),lead,copper,cadmium and mercury in various foods were tested.Aluminum was determined using the method for determination of spectrophotometry.Results The detection rates of lead,cadmium,mercury in the nine categories of food were 52.8% (341/646),62.1% (401/646),51.7% (334/646);the detection rates of copper in the meat was 90.0% (27/30);the aluminum in flour food was 84.8% (56/66),respectively.Compared with the national standards,the eligible rates of lead,cadmium,mercury,copper and aluminum were 97.1% (627/646),98.2% (539/549),100.0% (646/646),100.0% (30/30) and 75.8% (50/66),respectively.Food contaminated by lead and cadmium were mainly distributed in preserved egg [lead detection rate 9.5% (2/21)],organs [lead detection rate 6.7% (2/30),cadmium detection rate 30.0% (9/30)],vegetables [lead detection rate 9.9% (8/90)] and a small amount of food products [lead detection rate 4.7% (7/150)].The levels of lead in fried flour food and fine dried noodles were higher [40.9% (9/22),36.4% (4/11)].Conclusions Food contamination by lead,cadmium,mercury and copper is not serious in Ningxia.The monitoring results of lead,cadmium,mercury and copper in food are satisfying in Ningxia

  20. Molecular mechanisms of the epithelial transport of toxic metal ions, particularly mercury, cadmium, lead, arsenic, zinc, and copper. Comprehensive progress report, October 1, 1975--December 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, R. H.

    1978-10-01

    Investigations were undertaken to elucidate the mode of transepithelial transport of potentially toxic metal ions across the gastrointestinal tract, with primary attention given to cadmium, zinc, and arsenic. In addition, the toxic effects of cadmium on the metabolism of vitamin D and calcium have been investigated in some detail. Several approaches have been taken, including studies on the localization of heavy metals in the intestinal mucosa, the effects of cadmium on various parameters of calcium metabolism, the modes of intestinal absorption of cadmium, arsenate, and zinc, and the interactions of heavy metals with each other and with calcium, phosphorus, and vitamin D. Details of these experiments are attached in the Comprehensive Progress Report.

  1. Short-term metallothionein inductions in the edible cockle Cerastoderma edule after cadmium or mercury exposure: Discrepancy between mRNA and protein responses

    Energy Technology Data Exchange (ETDEWEB)

    Paul-Pont, Ika, E-mail: i.paulpont@epoc.u-bordeaux1.fr [Universite Bordeaux 1 - CNRS, UMR 5805 EPOC, CNRS, Station Marine d' Arcachon, Place du Dr. Peyneau, Arcachon 33120 (France); Gonzalez, Patrice, E-mail: p.gonzalez@epoc.u-bordeaux1.fr [Universite Bordeaux 1 - CNRS, UMR 5805 EPOC, CNRS, Station Marine d' Arcachon, Place du Dr. Peyneau, Arcachon 33120 (France); Baudrimont, Magalie, E-mail: m.baudrimont@epoc.u-bordeaux1.fr [Universite Bordeaux 1 - CNRS, UMR 5805 EPOC, CNRS, Station Marine d' Arcachon, Place du Dr. Peyneau, Arcachon 33120 (France); Nili, Hanane, E-mail: h.nili@etu.u-bordeaux1.fr [Universite Bordeaux 1 - CNRS, UMR 5805 EPOC, CNRS, Station Marine d' Arcachon, Place du Dr. Peyneau, Arcachon 33120 (France); Montaudouin, Xavier de, E-mail: x.de-montaudouin@epoc.u-bordeaux1.fr [Universite Bordeaux 1 - CNRS, UMR 5805 EPOC, CNRS, Station Marine d' Arcachon, Place du Dr. Peyneau, Arcachon 33120 (France)

    2010-05-05

    Metallothioneins (MT) are essential metal binding proteins involved in metal homeostasis and detoxification in living organisms. Numerous studies have focused on MT response to metal exposure and showed an important variability according to species, metal, concentration and time of exposure. In this study, the expression of one isoform of MT gene (Cemt1) and associated MT protein synthesis were determined after 1, 3, 9, 24, 72 and 168 h of cadmium (Cd) or mercury (Hg) exposures in gills of the cockle Cerastoderma edule. This experiment, carried out in laboratory conditions, revealed that in Cd-exposed cockles, induction of Cemt1 is time-dependent following a 'pulse-scheme' with significant upregulation at 24 h and 168 h intersected by time point (72 h) with significant downregulation. MT protein concentration increases with time in gills of exposed cockles in relation with the progressive accumulation of Cd in soluble fraction. On contrary, Hg exposure does not lead to any induction of Cemt1 mRNA expression or MT protein synthesis compared to control, despite a higher accumulation of this metal in gills of cockles compared to Cd. The localization of Hg (85-90%) is in insoluble fraction, whereas MT was located in the cytoplasm of cells. This gives us a first clue to understand the inability of Hg to activate MT synthesis. However, other biochemical processes probably occur in gills of C. edule since the remaining soluble fraction of Hg exceeds MT sequestration ability. Finally, since one of the first main targets of metal toxicity in cells was the mitochondria, some genes involved in mitochondria metabolism were also analyzed in order to assess potential differences in cellular damages between two metal exposures. Indeed, until T{sub 168}, no impact on mitochondrial genes was shown following Hg exposure, despite the complete lack of MT response. This result indicated the presence of other effective cellular ligands which sequester the cytosolic fraction of

  2. Bioavailability of cadmium, copper, mercury, lead, and zinc in subtropical coastal lagoons from the southeast Gulf of California using mangrove oysters (Crassostrea corteziensis and Crassostrea palmula).

    Science.gov (United States)

    Páez-Osuna, Federico; Osuna-Martínez, Carmen C

    2015-02-01

    Cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn) were assessed in the edible tissues of Crassrotrea corteziensis oysters collected during the rainy and dry seasons in 27 sites from 8 coastal lagoons of the southeast Gulf of California. In addition, C. palmula oysters were sampled at 9 sites from the same mangrove roots where C. corteziensis oysters were collected. Metal analyses were performed by flame atomic absorption spectrophotometry (Cd, Cu, and Zn), graphite furnace (Pb), and cold vapor detection (Hg). The obtained mean levels were (µg g(-1) dry weight) as follows: Cd 6.05 ± 2.77, Cu 60.0 ± 33.4, Hg 0.38 ± 0.17, Pb 1.11 ± 0.63, and Zn 777 ± 528 µg g(-1). For all metals except Hg, the concentrations were greater during dry season than during rainy seasons. The high levels, particularly that for Cd, were related to upwelling along the eastern Gulf of California. High Hg levels in the rainy season were associated with the transport of materials from the watershed to the lagoon. Shrimp farming, agriculture, and other sources were considered as potential sources to explain the differences in metal bioavailability in the 8 lagoons. The mean concentrations of Cd (Santa María-La Reforma lagoon), Cu [San Ignacio-Navachiste-El Macapule (SINM), Urías (URI), and Altata-Ensenada del Pabellón lagoons], and zinc (Zn) (URI, Santa María-Ohuira-Topolobampo, El Colorado, and SINM lagoons) during the dry season were greater than the maximum permissible limits. C. palmula collected in 8 sites where they were present simultaneously with C. corteziensis had consistently greater metal levels than C. corteziensis, but correlation analyses showed a high and significant (P < 0.05) correlation between metal concentrations in both species. The correlation equations obtained are useful where the same species is not distributed and is necessary to compare results from distinct regions.

  3. Effect of mercury, cadmium, nickel, chromium and zinc on kinetic properties of NADPH-cytochrome P450 reductase purified from leaping mullet (Liza saliens).

    Science.gov (United States)

    Bozcaarmutlu, Azra; Arinç, Emel

    2007-04-01

    Information on the mechanism of metal ion inhibition of NADPH-cytochrome P450 reductase is limited. The purpose of the present paper was to elucidate in vitro effect of Hg(+2), Cd(+2), Ni(+2), Cr(+3) and Zn(+2) ions on the purified mullet NADPH-cytochrome P450 reductase. NADPH-cytochrome P450 reductase was purified from detergent-solubilized liver microsomes from leaping mullet (Liza saliens). All of the metal ions caused inhibition of the enzyme activity except Zn(+2). At 50 microM metal concentration, Hg(+2) inhibited the cytochrome P450 reductase activity completely (100%), while, at the same concentrations, Cd(+2), Cr(+3) and Ni(+2) caused 66%, 65% and 37% inhibition, respectively. At 50 microM metal concentration, Zn(+2) had no apparent effect on cytochrome P450 reductase activity. The IC(50) values of HgCl(2), CrCl(3), CdCl(2) and NiCl(2) were estimated to be 0.07 microM, 24 microM, 33 microM and 143 microM, respectively. Of the metal ions tested, Hg(+2) exhibited much higher inhibitory effect at lower concentrations, so it was evidently a more potent inhibitor than the others. All four metal ions displayed noncompetitive type of inhibition mechanism for the purified reductase as analyzed by Dixon plot. K(i) values of Hg(+2), Cr(+3), Cd(+2), and Ni(+2) were calculated from Dixon plots as 0.048 microM, 18 microM, 73 microM and 329 microM, respectively.

  4. Metal accumulation in human tissues. Vol. 6. Chromium, nickel, lead, cadmium, and zinc in liver, lungs, spleen, and kidneys. Metallanreicherungen in Humangeweben. Bd. 6. Chrom, Nickel, Blei, Cadmium und Zink in Lunge, Leber, Milz und Niere

    Energy Technology Data Exchange (ETDEWEB)

    Kollmeier, H.; Seemann, J.; Wittig, P.; Witting, C.; Rothe, G.

    1985-01-01

    This paper presents the results of the analytical determination of Cr, Ni, Pb, Cd, and Zn in human lungs, livers, spleens, and kidneys by means of flameless atomic absorption spectrometry, and this on an individual and on a group basis; individually as a combined record which contains the trace metal concentrations of the investigated tissues and the post-mortem findings obtained by autopsy. The retrieval of the findings in case of certain diseases is realized by an index. The tissue concentrations of those metals depend upon many endogenous and exogenous variables, especially as regards time and place. Thus, often interpretations are only possible on an individual basis. For example, we measured an increased tissue concentration of lead in a cadaver which perinatally died of severe vasal malformations. On the other hand, we found a highly positive correlation between age and chromium and nickel content of lungs, which might be interesting in regard to occupational lung cancer. In relation to our results we tried to establish reference levels. However, the interpretation of the measurements remains difficult. Within the scientific literature the results of such studies are very different, and this both in regard to the analytical method used and to the year of publication. This fact is demonstrated by tabular overviews of the investigated metals and tissues. Furthermore, problems of organisation of getting samples, of avoiding sample contamination, of quality assurance etc. are discussed.

  5. Role of direct reactivity with metals in chemoprotection by N-acetylcysteine against chromium(VI), cadmium(II), and cobalt(II).

    Science.gov (United States)

    Luczak, Michal W; Zhitkovich, Anatoly

    2013-12-01

    The antioxidant N-acetylcysteine (NAC) is widely used for the assessment of the role of reactive oxygen species (ROS) in various biological processes and adverse drug reactions. NAC has been found to effectively inhibit the toxicity of carcinogenic metals, which was attributed to its potent ROS-suppressive properties. However, the absence of redox activity among some metals and findings from genetic models suggested a more diverse, smaller role of oxidative stress in metal toxicity. Here, we examined mechanisms of chemoprotection by NAC against Cd(II), Co(II), and Cr(VI) in human cells. We found that NAC displayed a broad-spectrum chemoprotective activity against all three metals, including suppression of cytotoxicity, apoptosis, p53 activation, and HSP72 and HIF-1α upregulation. Cytoprotection by NAC was independent of cellular glutathione. NAC strongly inhibited the uptake of all three metals in histologically different types of human cells, explaining its high chemoprotective potential. A loss of Cr(VI) accumulation by cells was caused by NAC-mediated extracellular reduction of chromate to membrane-impermeative Cr(III). Suppression of Co(II) uptake resulted from a rapid formation of Co(II)-NAC conjugates that were unable to enter cells. Our results demonstrate that NAC acts through more than one mechanism in preventing metal toxicity and its chemoprotective activity can be completely ROS-independent. Good clinical safety and effectiveness in Co(II) sequestration suggest that NAC could be useful in the prevention of tissue accumulation and toxic effects of Co ions released by cobalt-chromium hip prostheses.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yangho [Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan (Korea, Republic of); Lee, Byung-Kook, E-mail: bklee@sch.ac.kr [Institute of Environmental and Occupational Medicine, Soonchunhyang University 646 Eupnae-ri, Shinchang-myun, Asan-si, Choongnam 336-745 (Korea, Republic of)

    2012-10-15

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

  7. Discrimination of mercury, cadmium and lead polluted rice leaves based on near infrared spectroscopy technology%基于近红外光谱的重金属汞、镉和铅污染水稻叶片鉴别

    Institute of Scientific and Technical Information of China (English)

    张龙; 潘家荣; 朱诚

    2013-01-01

    There are hundreds of sources of heavy metal pollution,including the industries of coal,natural gas,paper,and mining.Toxic heavy metals,such as mercury,cadmium and lead,in air,soil,and water are global problems that are a growing threat to humanity.Rice is an important food crop in world,the rice polluted with heavy metal is seriously harmful to people's health.There are many methods to detect the heavy metal,such as inductively coupled plasma-mass spectrometry (ICP-MS),inductively coupled plasma-atomic emission spectrometer (ICP-AES),inductively coupled plasma optical emission spectrometry (ICP-OES),atomic absorption spectrometry (AAS),X ray fluorescence spectrometry (XRF),atomic fluorescence spectrometry (AFS) and so on.Although there are many advantages in the above technologies respectively,they are time-consuming,high-cost and sometimes require considerable analytic skill.Nowadays,as near infrared spectroscopy (NIR) responds to molecular energy transitions associated with hydrogen bonds of organic,while inorganic salts are not expected to directly influence NIR spectra.To our interest,several studies have described useful NIR calibrations for minerals analysis.NIR spectra with supposed NIR-transparent minerals may be due to the association of cations with organic or hydrated inorganic molecules.Thus,in order to develop the fast detective technology on heavy metal polluted rice leaves,NIR was combined with pattern recognition to discriminate the mercury,cadmium and lead in polluted rice leaves. The rice was grown in paddy field polluted by mercury,cadmium and lead,the concentration of which was 1.5,1 and 500 mg/kg respectively.After 50 days growth,the absorbance of near infrared spectroscopy of back of flag leaf was detected with Nicolet Nexus 870 (Thermo Corporation USA) and the data was collected with the software of Omnic 7.0.The acquired spectra of leaves with different heavy metal treatments were firstly pretreated with wavelet transform and then input in

  8. 混合基体改进剂-石墨炉原子吸收光谱法测定速溶茶中的铅镉铬%Detection of lead, cadmium and chromium in instant tea by mixed matrix modifier-graphite furnace atomic absorption spectrometry

    Institute of Scientific and Technical Information of China (English)

    叶佩琳; 胡银凤; 朱宏斌; 姚射月; 岳鹏翔

    2015-01-01

    Objective To establish a method for the determination of heavy metal lead, chromium and cadmium in instant tea by graphite furnace atomic absorption spectrometry (GFAAS) with microwave digestion. Methods Solid instant tea powder was slaked in high pressure sealed microwave digestion instrument, with adding ammonium nitrate, nitric acid matrix modifier for eliminating the sample disturbance. Instrument conditions were optimized for graphite furnace atomic spectrometry. Results The optimal matrix modifiers for the determination of lead, chromium, cadmium in instant tea were ammonium nitrate and palladium nitrate mixed matrix modifier, palladium nitrate as matrix modifier, ammonium nitrate and palladium nitrate mixed matrix modifier, respectively. Under the optimum experimental conditions, the linear ranges of lead, chromium and cadmium were 0~80 μg/L, 0~40 μg/L, and 0~2 μg/L and their detection limits were 0.3681 μg/L, 0.1268 μg/L, and 0.0076 μg/L. The correlation coefficients of lead, cadmium and chromium standard curve were 0.9990, 0.9978 and 0.9992, respectively. The recoveries rate were between 98.64%~101.9% and the relative standard deviation was less than 5%. Conclusion This method is simple, rapid and accurate, which can be used as a fast and reliable method for the determination of the lead, cadmium and chromium in instant tea.%目的:以微波消解为前处理方式,建立一种石墨炉原子吸收光谱法测定速溶茶中微量重金属铅、铬、镉的实验方法。方法采用高压密闭微波消解仪对速溶茶进行消解,加入硝酸铵、硝酸钯等基体改进剂消除样品干扰,并优化仪器条件进行石墨炉原子法测定。结果测定速溶茶中铅、铬、镉的最佳基体改进剂分别为硝酸铵-硝酸钯混合基体改进剂、硝酸钯基体改进剂、硝酸铵-硝酸钯混合基体改进剂。在最佳实验条件下,铅、铬、镉的线性范围分别为0~80μg/L、0~40μg/L、0~2μg/L,检出限分别为0

  9. Hematological Changes Induced by Mercury Ions and Ionizing Radiation in Experimental Animals

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin-Kyu; Lee, Yun-Jong; Choi, Dae-Seong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Kim, Ji-Hyang [Biotechnology Research Institute, Seoul (Korea, Republic of); Cebulska-Wasilewska, Antonina [The Henryk Niewodniczanski Institute of Nuclear Physics, Krakow (Poland)

    2006-07-01

    Toxic metals such as lead, chromium, cadmium, mercury and arsenic are widely found in our environment. Humans are exposed to these metals from numerous sources, including contaminated air, water, soil and food. Mercury, one of the most diffused and hazardous organ specific environmental contaminants, exists in a wide variety of physical and chemical states, each of which has unique characteristics for a target organ specificity. Although reports indicate that mercury induces deleterious damage, little is known about its effects on living organisms. Ionizing radiation, an extensively used therapeutic modality in oncology, not only eradicates neoplastic cells but also generates inevitable side effects for normal tissues. Such biological effects are made through the production of reactive oxygen species which include a superoxide anion, a hydroxyl radical and a hydrogen peroxide. These reactive species may contribute to the radiation-induced cytotoxicity (e.g., chromosome aberrations, protein oxidation, and muscle injury) and to the metabolic and morphologic changes (e.g., increased muscle proteolysis and changes in the central nervous system) in animals and humans. In the present study, radioimmunoassay of the cortisol in the serum and the analysis of the hematological components and enzymes related to a tissue injury were carried out to evaluate the effects of mercury chloride in comparison with those of ionizing radiation.

  10. Cyto-histological and morpho-physiological responses of common duckweed (Lemna minor L.) to chromium.

    Science.gov (United States)

    Reale, L; Ferranti, F; Mantilacci, S; Corboli, M; Aversa, S; Landucci, F; Baldisserotto, C; Ferroni, L; Pancaldi, S; Venanzoni, R

    2016-02-01

    Along with cadmium, lead, mercury and other heavy metals, chromium is an important environmental pollutant, mainly concentrated in areas of intense anthropogenic pressure. The effect of potassium dichromate on Lemna minor populations was tested using the growth inhibition test. Cyto-histological and physiological analyses were also conducted to aid in understanding the strategies used by plants during exposure to chromium. Treatment with potassium dichromate caused a reduction in growth rate and frond size in all treated plants and especially at the highest concentrations. At these concentrations the photosynthetic pathway was also altered as shown by the decrease of maximum quantum yield of photosystem II and the chlorophyll b content and by the chloroplast ultrastructural modifications. Starch storage was also investigated by microscopic observations. It was the highest at the high concentrations of the pollutant. The data suggested a correlation between starch storage and reduced growth; there was greater inhibition of plant growth than inhibition of photosynthesis, resulting in a surplus of carbohydrates that may be stored as starch. The investigation helps to understand the mechanism related to heavy metal tolerance of Lemna minor and supplies information about the behavior of this species widely used as a biomarker.

  11. 安徽省市售大米铅、镉、汞污染状况及健康风险评价%Pollution and Risk Evaluation of Lead, Cadmium and Mercury in Rice in the markets of Anhui Province

    Institute of Scientific and Technical Information of China (English)

    许瑶

    2011-01-01

    测定安徽省市售大米中的重金属元素铅、镉、汞,评估其污染状况,并进行健康风险评价,为保障人们饮食安全提供科学依据。采用ICP—MS法,共检测了101份样品。其中铅检出率为40%,超标率为0;镉检出率为100%,超标率为0;汞检出率为69%,超标率为0。健康风险评价结果表明,安徽省市售大米中的铅、镉、汞对人体健康风险影响较小,镉对人体健康影响存在一定的风险。%To determine heavy metals of lead, cadmium and mercury in rice in the market of Anhui Province, assess the pollution condition, do health risk evaluation and provide the scientific basis for safeguarding people's diet security. The determination is conducted by means of ICP-MS. 101 samples are tested. The detection rate of lead is 40%, and the overcontent rate is zero. The detection rate of cadmium is 100%, and the overcontent rate is zero. The detection rate of mercury is 69%, and the overcontent rate is zero. Health risk evaluation results show that the content of lead, cadmium and mercury in rice in the markets of Anhui Province have little influence on people's health. But the content of cadmium has some risk to people's health.

  12. Estado de conocimiento de las concentraciones de cadmio, mercurio y plomo en organismos acuáticos de Venezuela - Current state of knowledge of the concentrations of cadmium, mercury and lead from aquatic organisms of Venezuela

    Directory of Open Access Journals (Sweden)

    Salazar Lugo, Raquel

    2009-11-01

    Full Text Available ResumenEn Venezuela, la contaminación por metales pesados está relacionadacon el desarrollo de la industria siderúrgica y petrolera, así como a la explotación indiscriminada de otros metales como el oro. Está bastante documentada la contaminación del lago de Maracaibo dado al desarrollo en sus cercanías de actividades urbanas, industriales, mineras y agropecuarias; del lago de Valencia, del río Tuy, Orinoco y Manzanares, entre otros En este trabajo se revisa el estado de conocimiento, en los últimos 10 años, de la concentración de plomo, cadmio y mercurio en especies acuáticas de diferentes áreas del País.SummaryContamination due to trace metals in Venezuela is related withindiscriminate exploitation of metals like gold, transport of river runoff, oil and siderurgica industries and urban zones. The Tuy, Orinoco, Tigre, Manzanares rivers and others basins as Valencia and Maracaibo lakes has been reported as polluted for many years. In this work, we reviewed the state of knowledge, in the last 10 years, of metals concentrations specially lead, cadmium and mercury, in aquatic species from diverse areas of country.

  13. Cadmium and Chrome Concentrations in Human Milk

    Directory of Open Access Journals (Sweden)

    Sima Nazarpour

    2014-04-01

    Full Text Available Introduction: Nutrition of children has the highest priority in any program aimed at children's health care. Milk contaminated with various toxic elements can have adverse effects on children's health. This study aimed to determine the concentration of heavy metals including cadmium(Cd and chromium (Cr of breast feeding women’s milk in Varamin. Methods: This is a cross sectional study. In the present study, chromium and cadmium levels in milk of 100 mothers attending clinics in the city of Varamin were measured in four to eight weeks after delivery, using atomic absorption spectrometry. Results: The mean values (±SD of Cd and Cr in human milk were 5±6.9 μg/ml and 3±2.7 μg/ml respectively. Result of Linear regression showed that cadmium levels were higher in breast milk of people living close to the factory or industrial center. Also, the chromium levels were higher in the breast milk of women in cases of: Smoking by spouses, consumption of imported rice, consumption of mineral water, and living close to the factory or an industrial center. Conclusion: This study showed that the relationship of some factors such as living near a factory or an industrial center, smoking by spouse, the type of consumed rice and water, with the level of cadmium and chromium. Cadmium and chromium levels of breast milk in this study were higher than the levels of these elements mentioned in the reviewed articles and international standard. Because some variables, such as living near a factory or an industrial center, smoking by spouse, the type of consumed rice and water can affect the amount of entering elements in breast milk. Actions can be taken to reduce or eliminate these variables in order to decrease the mentioned elements in human milk.

  14. Bis(3-methyl-2-pyridyl)ditelluride and pyridyl tellurolate complexes of zinc, cadmium, mercury: Synthesis, characterization and their conversion to metal telluride nanoparticles.

    Science.gov (United States)

    Kedarnath, G; Jain, Vimal K; Wadawale, Amey; Dey, Gautam K

    2009-10-21

    Treatment of an acetonitrile solution of metal chloride with bis(3-methyl-2-pyridyl)ditelluride, [Te(2)(pyMe)(2)], in the same solvent yielded complexes of composition [MCl(2){Te(2)(pyMe)(2)}] (M = Zn or Cd) whereas reactions of [MCl(2)(tmeda)] with NaTepyR (R = H or Me) gave tellurolate complexes of the general formula [M(TepyR)(2)] (M = Cd or Hg). When the cadmium complex [Cd(Tepy)(2)] was crystallized in the presence of excess tmeda, [Cd(Tepy)(2)(tmeda)] was formed exclusively. These complexes were characterized by elemental analyses, uv-vis, (1)H NMR data. The crystal structures of [ZnCl(2){Te(2)(pyMe)(2)}] and [Cd(Tepy)(2)(tmeda)] were established by single crystal X-ray diffraction. In the former zinc is coordinated to nitrogen atoms of the pyridyl group, while in the latter the coordination environment around tetrahedral cadmium is defined by the two neutral nitrogen atoms of tmeda, and two pyridyl tellurolate ligands. Thermal behavior of some of these complexes was studied by thermogravimetric analysis. Pyrolysis of [M(Tepy)(2)] in a furnace or in coordinating solvents such as hexadecylamine/tri-n-octylphosphine oxide (HDA/TOPO) at 350 and 160 degrees C, respectively gave MTe nanoparticles, which were characterized by uv-vis, photoluminiscence, XRD, EDAX and TEM.

  15. Perturbed Angular Correlation Study of the Static and Dynamic Aspects of Cadmium and Mercury Atoms Inside and Attached to a C60 Fullerene Cage

    CERN Document Server

    Das, Satyendra K; Banerjee, Debasish; Johnston, Karl; Das, Parnika; Butz, Tilman; Amaral, Vitor S; Correia, Joao G; Barbosa, Marcelo B

    2014-01-01

    30 keV Cd-111m and 50 keV Hg-199m beams from ISOLDE were used to implant on preformed targets of C-60 with a thickness of 1 mg cm(-2). Endofullerene compounds, viz. Cd-111m@C-60 and Hg-199m@C-60 formed during implantation were separated by filtration through micropore filter paper followed by solvent extraction. Dried samples of the endofullerene compounds were counted for the time differential perturbed angular correlation (TDPAC) measurement using the coincidence of the 151-245 keV cascade of Cd-111m and the 374 158 keV cascade of Hg-199m on a six LaBr3(Ce) detector system coupled with digital electronics. The results for 111mCd@C60 indicate a single static component (27\\%) and a fast relaxing component (73\\%), the latter implying that the cadmium atom moves rapidly inside the cage at room temperature. The quadrupole interaction frequency and asymmetry parameter of the cadmium atom occupying the static site in C60 are omega(Q) = 8.21(36) Mrad s(-1) and eta = 0.41(9), respectively. The fast relaxation con...

  16. Mercury in U.S. coal—Priorities for new U.S. Geological Survey studies

    Science.gov (United States)

    Kolker, Allan

    2016-05-09

    In 2011, the U.S. Environmental Protection Agency (EPA) introduced emissions standards, known as Mercury and Air Toxics Standards (MATS), for a range of toxic constituents from coal-fired utility power stations and other combustion sources. This report presents the findings of an expert panel convened in September 2014 to assess the role of the U.S. Geological Survey (USGS) in new coal investigations that would be useful to stakeholders under MATS. Panel input is provided as summaries of responses to a questionnaire distributed to participants. The panel suggests that the USGS continue its work on trace elements in coal and include more information about delivered coals and boiler feed coals, in comparison to previous USGS compilations that emphasized sampling representative of coals in the ground. To be useful under multipollutant regulatory standards, investigation of a range of constituents in addition to mercury would be necessary. These include other toxic metals proposed for regulation, such as arsenic, nickel, cadmium, and chromium, as well as the halogens chlorine and fluorine, which upon emission form harmful acid gases. Halogen determinations are also important because they influence mercury speciation in flue gas, which allows the effectiveness of mercury controls to be assessed and predicted. The panel suggests that the Illinois Basin and the Powder River Basin should have the highest priority for new coal quality investigations in the near term by the USGS, on the basis of current economic conditions and overall economic importance, respectively. As a starting point for new investigations, brief summaries of the distribution of mercury in each coal basin, and their potential for further investigation, are presented.

  17. Distribution and age-related bioaccumulation of lead (Pb), mercury (Hg), cadmium (Cd), and arsenic (As) in tissues of common carp (Cyprinus carpio) and European catfish (Sylurus glanis) from the Buško Blato reservoir (Bosnia and Herzegovina).

    Science.gov (United States)

    Has-Schön, Elizabeta; Bogut, Ivan; Vuković, Rosemary; Galović, Dalida; Bogut, Ante; Horvatić, Janja

    2015-09-01

    The purpose of this study was to quantify the bioaccumulation of Pb, Hg, Cd, and As in tissues of carp (Cyprinus carpio) and catfish (Silurus glanis) from Buško Blato in Bosnia and Herzegovina. Arsenic concentrations were below the Maximal Admissible Concentration (MAC) for Croatia and other countries. Mercury concentrations were below 1 mg kg(-1), but in most muscle samples of both species and all catfish liver samples, the values were higher than 0.5 mg kg(-1) (higher than the MAC for many countries including Croatia). Lead concentrations were higher than 1 mg kg(-1) (the MAC for Croatia) in most muscle samples; all kidney and most catfish liver samples also exceeded 1 mg kg(-1). Cadmium concentrations in all tissues, other than the gonads, were higher than 0.1 mg kg(-1) (MAC for Croatia), with the highest concentrations found in the kidneys. The only gender difference was found in carp, where a 68.4% higher concentration of As was found in the fry compared to the milt (P<0.05). Concentrations of all of the elements were higher in catfish compared to carp for most tissues. Significant correlations were found between all of the elements in the muscles and the liver of carp. In catfish, the muscles were the only tissue in which multiple correlations were found. Linear positive correlations with age and body mass were demonstrated for the concentrations of all heavy metals for all tissues except the gonads in both fish species. We concluded that significant heavy metal accumulation in carp and a catfish tissues correlates with age and body mass; bioaccumulation is species- and tissue-specific and is different for each element.

  18. Chromium in diet

    Science.gov (United States)

    The best source of chromium is brewer's yeast. However, many people do not use brewer's yeast because it causes bloating ( abdominal distention ) and nausea . Other good sources of chromium include ...

  19. Heterogeneous chromium catalysts

    NARCIS (Netherlands)

    2005-01-01

    The present invention relates to a heterogeneous chromium catalyst system for the polymerisation of ethylene and/or alpha olefins prepared by the steps of: (a) providing a silica-containing support, (b) treating the silica-containing support with a chromium compound to form a chromium-based silica-c

  20. Cadmium exposure induces hematuria in Korean adults

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seung Seok [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Kim, Myounghee, E-mail: dkkim73@gmail.com [Department of Dental Hygiene, College of Health Science, Eulji University, Gyeonggi-do 461-713 (Korea, Republic of); Lee, Su Mi [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Lee, Jung Pyo [Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul 156-707 (Korea, Republic of); Kim, Sejoong [Department of Internal Medicine, Seoul National University Bundang Hospital, Gyeonggi-do 463-707 (Korea, Republic of); Joo, Kwon Wook [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Lim, Chun Soo [Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul 156-707 (Korea, Republic of); Kim, Yon Su; Kim, Dong Ki [Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of)

    2013-07-15

    Introduction: Toxic heavy metals have adverse effects on human health. However, the risk of hematuria caused by heavy metal exposure has not been evaluated. Methods: Data from 4701 Korean adults were obtained in the Korean National Health and Nutritional Examination Survey (2008–2010). Blood levels of the toxic heavy metals cadmium, lead, and mercury were measured. Hematuria was defined as a result of ≥+1 on a urine dipstick test. The odds ratios (ORs) for hematuria were measured according to the blood heavy metal levels after adjusting for multiple variables. Results: Individuals with blood cadmium levels in the 3rd and 4th quartiles had a greater OR for hematuria than those in the 1st quartile group: 3rd quartile, 1.35 (1.019–1.777; P=0.037); 4th quartile, 1.52 (1.140–2.017; P=0.004). When blood cadmium was considered as a log-transformed continuous variable, the correlation between blood cadmium and hematuria was significant: OR, 1.97 (1.224–3.160; P{sub trend}=0.005). In contrast, no significant correlations between hematuria and blood lead or mercury were found in the multivariate analyses. Discussion: The present study shows that high cadmium exposure is associated with a risk of hematuria. -- Highlights: • A high level of blood cadmium is associated with a high risk of hematuria. • This correlation is independent of several confounding factors. • Blood levels of lead and mercury are not associated with risk of hematuria. • This is the first study on the correlation between cadmium exposure and hematuria risk.

  1. 江浙沪皖地区18~22周岁男性血镉、尿汞参考区间探讨%Investigation on the reference intervals of blood cadmium and urine mercury in Jiangsu, Zhejiang,Shanghai and Anhui regions among 18-22-year-old males

    Institute of Scientific and Technical Information of China (English)

    潘畅; 林炜栋; 周钢; 陈向芳

    2013-01-01

    目的 探讨江苏(简称江)、浙江(简称浙)、上海(简称沪)、安徽(简称皖)地区18 ~ 22周岁男性血镉、尿汞参考区间,为消防员职业健康体检的重金属筛查提供更为切合实际的参考标准.方法 使用原子吸收分光光度法对1 683名新入伍消防员进行血镉测定.使用酸性氯化亚锡还原法进行尿汞测定,结果 采用肌酐(Cr)校正.再对血镉、尿汞值进行统计学分析,参考区间按P0~ P95计算;同时分地域、是否吸烟比较.结果 江浙沪皖地区18 ~ 22周岁男性血镉值呈正偏态分布,参考区间为0~ 6.70 μg/L;尿汞值呈正偏态分布,参考区间为0~3.00 μg/g Cr;地域之间比较差异无统计学意义(P>0.05);吸烟与非吸烟组比较差异有统计学意义(P<0.05).结论 血镉、尿汞参考区间应区分不同地区、不同年龄建立参考区间.%Objective To investigate the reference intervals of blood cadmium and urine mercury in Jiangsu, Zhejiang, Shanghai and Anhui regions among 18-22-year-old males, and to provide realistic reference standards for firefighter occupational health examination of heavy metal screening. Methods The atomic absorption spectrophotometry was used for blood cadmium determination in 1 683 new firefighters. The acidic stannous chloride reduction method was used for the determination of urine mercury, and the results were calibrated by creatinine( Cr). The blood cadmium and urine mercury values were analyzed statistically. The results were classified and analyzed comparatively according to regions and smoking with reference intervals calculated by P0-P95- Results In Jiangsu, Zhejiang, Shanghai and Anhui regions among 18-22-year-old males, the blood cadmium values were positively skewed distribution, and the reference interval was 0-6.70 μg/L. Urine mercury values were positively skewed distribution, and the reference interval was 0-3. 00 μg/g Cr. The regional comparison had no statistical significance (P

  2. Simultaneous determination of arsenic, cadmium, calcium, chromium, cobalt, copper, iron, lead, magnesium, manganese, molybdenum, nickel, selenium, and zinc in fertilizers by microwave acid digestion and inductively coupled plasma-optical emission spectrometry detection: single-laboratory validation of a modification and extension of AOAC 2006.03.

    Science.gov (United States)

    Webb, Sharon; Bartos, James; Boles, Rhonda; Hasty, Elaine; Thuotte, Ethel; Thiex, Nancy J

    2014-01-01

    A single-laboratory validation study was conducted for the simultaneous determination of arsenic, cadmium, calcium, cobalt, copper, chromium, iron, lead, magnesium, manganese, molybdenum, nickel, selenium, and zinc in all major types of commercial fertilizer products by microwave digestion and inductively coupled plasma-optical emission spectroscopy analysis. This validation study proposes an extension and modification of AOAC 2006.03. The extension is the inclusion of calcium, copper, iron, magnesium, manganese, and zinc, and the modification is incorporation of hydrochloric acid in the digestion system. This dual acid digestion utilizes both hydrochloric and nitric acids in a 3 to 9 mL volume ratio/100 mL. In addition to 15 of the 30 original validation materials used in the 2006.03 collaborative study, National Institute of Standards and Technology Standard Reference Material 695 and Magruder 2009-06 were incorporated as accuracy materials. The main benefits of this proposed method are a significant increase in laboratory efficiency when compared to the use of both AOAC Methods 965.09 and 2006.03 to achieve the same objective and an enhanced recovery of several metals.

  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. [Mercury poisoning].

    Science.gov (United States)

    Bensefa-Colas, L; Andujar, P; Descatha, A

    2011-07-01

    Mercury is a widespread heavy metal with potential severe impacts on human health. Exposure conditions to mercury and profile of toxicity among humans depend on the chemical forms of the mercury: elemental or metallic mercury, inorganic or organic mercury compounds. This article aims to reviewing and synthesizing the main knowledge of the mercury toxicity and its organic compounds that clinicians should know. Acute inhalation of metallic or inorganic mercury vapours mainly induces pulmonary diseases, whereas chronic inhalation rather induces neurological or renal disorders (encephalopathy and interstitial or glomerular nephritis). Methylmercury poisonings from intoxicated food occurred among some populations resulting in neurological disorders and developmental troubles for children exposed in utero. Treatment using chelating agents is recommended in case of symptomatic acute mercury intoxication; sometimes it improves the clinical effects of chronic mercury poisoning. Although it is currently rare to encounter situations of severe intoxication, efforts remain necessary to decrease the mercury concentration in the environment and to reduce risk on human health due to low level exposure (dental amalgam, fish contamination by organic mercury compounds…). In case of occupational exposure to mercury and its compounds, some disorders could be compensated in France. Clinicians should work with toxicologists for the diagnosis and treatment of mercury intoxication.

  5. Basic Information about Mercury

    Science.gov (United States)

    ... other organic compounds, elemental (metallic) mercury, and inorganic mercury compounds. Methylmercury and other organic mercury compounds are formed when mercury combines with carbon. Microscopic ...

  6. 酿酒酵母对锦鲤鱼体内铜、汞、镉三种重金属排除效果的比较研究%Effect of Saccharomyces cerecisiae on purification of copper,mercury and cadmium in organ of Cyprinus carpioi

    Institute of Scientific and Technical Information of China (English)

    张金硕; 许晓曦; 滕国新

    2011-01-01

    By exposing fish ( Cyprinus carpioi)to the single heavy metal solutions, including copper, mercury and cadmium, Saccharomyces cerecisiae was selected as feeds additive to investigate the effects of visceral, gill and muscle purification.The results showed that Saccharomy cerecisiae had an effect on the purification of the three kinds of heavy metals accumulated in visceral,gill and muscle.The effect of purification on copper was:muscle >gill > visceral,the effect of purification on mercury was:visceral > muscle > gill,the effect of purification on cadmium was:muscle ≈ visceral > gill.In summary, Saccharomyces cerecisiae had a good effect on purification of cadmium and mercury, it can remove most of heavy metal ion accumulated in muscle and become relative weaker on the purification of copper.Saccharomyces cerecisiae had main effect on visceral and muscle,but little effect on gill.%通过对锦鲤鱼幼鱼进行铜、汞、镉的单一重金属积累实验和排除实验,研究了以酿酒酵母作为饲料添加剂对锦鲤鱼内脏、鳃和肉的排除作用效果.结果表明,酿酒酵母对锦鲤鱼体内脏、鳃和肌肉中积累的铜、汞、镉均有排除作用,其中对Cu的排除效果比较为肌肉>鳃>内脏;对Hg的排除效果比较为内脏>肌肉>鳃;对Cd的排除效果比较为肌肉≈内脏>鳃.综合比较得出,酿酒酵母对鱼体内Cd和Hg的排除效果显著,可以排除鱼肉中绝大多数的重金属离子.对Cu的排除效果相对减弱.酿酒酵母对鱼体内的重金属排除效果主要体现在内脏和肌肉中,而对鱼鳃的排除效果不明显.

  7. Mercury-binding proteins of Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Roesijadi, G.; Morris, J. E.; Calabrese, A.

    1981-11-01

    Mytilus edulis possesses low molecular weight, mercury-binding proteins. The predominant protein isolated from gill tissue is enriched in cysteinyl residues (8%) and possesses an amino acid composition similar to cadmium-binding proteins of mussels and oysters. Continuous exposure of mussels to 5 ..mu..g/l mercury results in spillover of mercury from these proteins to high molecular weight proteins. Antibodies to these proteins have been isolated, and development of immunoassays is presently underway. Preliminary studies to determine whether exposure of adult mussels to mercury will result in induction of mercury-binding proteins in offspring suggest that such proteins occur in larvae although additional studies are indicated for a conclusive demonstration.

  8. Mercury(6)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    31. Since Mariner Ten's flight, astronomers have been trying to find out more about Mercury. Telescopes, including the orbiting Hubble Space Telescope,cannot help much. They would be damaged by the bright light of the sun if they turned to look at Mercury. So, astronomers are studying Mercury from observatories on Earth. They are recording information about the planet's radiation.

  9. Comtamination of Cadmium and Mercury in Farmland of Tianjin and Extration Methods for Predicting Their Bioavailability%天津农田土壤镉和汞污染及有效态提取剂筛选

    Institute of Scientific and Technical Information of China (English)

    王婷; 王静; 孙红文; 张彦峰

    2012-01-01

    Irrigation of sewage water has been applied for agriculture production in Tianjin for over SO years, since Tianjin is a city lacking water resource seriously. Heavy metals in soils could not be degraded, but accumulated, causing hazards to human beings though food-chain. Twenty-two sites of samples (including pairing soil and lettuce) were collected from seriously polluted areas along the three sewage rivers in Tianjin, and the contents of cadmium (Cd) and mercury (Hg) were measured. Moreover,different extraction methods were studied to check their applicability for predicting bioavailability of the two metals. Nine of the 22 soils exceeded the National Soil Quality Standard Ⅱ for Cd (0.6 mg·kg-1) and 7 exceeded the standard for Hg( 1.0 mg·kg-1). Over 60% percent of Cd concentration in lettuce exceeded the National Food Quality and Safety Standard for Cd(0.2 mg· kg-1), while the Hg concentrations of all the samples exceeded the standard for Hg(0.01 mg·kg-1). Hence, the heavy metal pollution has threatened the safty of vegetable. The metal contents in lettuce did not correlate with those in soils, wich were influenced by soil physico-chemical properties. Of five extraction solvents tested (HC1, CaCl2, NH4AC, diethylene-triamine-pentaacetic acid(DTPA) and M3), M3 and DTPA showed good capacity for predicting the bioavailability of Cd, with the correlative coefficients(R) being 0.92 and 0.88 respectively. M3 showed better correlation, moreover, it cost shorter time for extraction. Hence, M3 was a promising method for Cd bioavailability prediction. However, both M3 and DTPA failed for the prediction of Hg bioavailability, showing a negative correlation for Hg (R=-0.82 and -0.47, respectively). This might be because Hg has caused adverse effects on lettuce, hindering the transfer of Hg from root to the edible part of lettuce.%采集天津3条排污河污灌区重金属污染农田的22个土壤及油麦菜样品,测定镉(Cd)和汞(Hg)的浓度,筛选两种重金

  10. Removal of chromium(VI) from aqueous solutions by polymer inclusion membranes.

    Science.gov (United States)

    Kozlowski, Cezary A; Walkowiak, Wladyslaw

    2002-11-01

    The transport through polymer inclusion membranes (PIMs) was found as the effective and selective method of chromium(VI) anions removal from chloride acidic aqueous solutions. The optimal PIMs content was as follows: 41 wt% of cellulose triacetate as the support, 23 wt% of tri-n-octylamine as the ionic carrier, and 36 wt% of o-nitrophenyl pentyl ether as the plasticizer. The results obtained show a linear decrease of permeability coefficient and initial flux values with source phase pH increase. Also linear decrease of initial flux in log-log scale with chromium(VI) concentration increase was observed. Value of slope of this relationship was found to be 0.96 which indicates a first order of chromium(VI) reaction with tri-n-octylamine at membrane/aqueous source interface. Transport of chromium(VI) through PIMs reduces the concentration of chromium(VI) in source aqueous phase from 1.0 to 0.0028 ppm, which is below permissible limit in drinking water in Poland. Competitive transport of chromium(VI), cadmium(II), zinc(II), and iron(III) from acidic aqueous solution across PIMs was found to be efficient for chromium(VI) (99%), and cadmium(II) (99%).

  11. Determination of the cadmium and copper content inherent to metallothionein

    Energy Technology Data Exchange (ETDEWEB)

    Raspor, B.; Kozar, S.; Pavicic, J.; Juric, D. [Ruder Boskovic Institute, Center for Marine Research Zagreb, P.O.B. 1016, HR-10 001 Zagreb (Croatia)

    1998-05-01

    The reliability of the voltammetric determination of the cadmium and copper content (at pH 1.0), inherent to metallothionein (MT) isolated from the digestive gland of Mytilus galloprovincialis, was investigated. An artifact signal enhancement of copper, caused by the cupric-thionein complex adsorption at the mercury electrode, was established. This artifact was removed by UV-digestion of the sample for 15-20 h prior to analysis. A similar artifact was not detected for cadmium, because at this pH the cadmium-thionein complex has dissociated, and cadmium exists in the ionic form. Therefore, the voltammetric analysis of the cadmium content can be performed directly at pH 1.0, without prior UV-digestion of the sample. (orig.) With 3 figs., 1 tab., 12 refs.

  12. Dislocation Etching Solutions for Mercury Cadmium Selenide

    Science.gov (United States)

    2014-09-01

    be obtained in order to develop better etching solutions. 13 6. References 1. Brill G, Chen Y, Wijewarnasuriya P. J. Elect. Mater. 2011;40...PJ, Jacobs RN, Markunas JK, Jaime-Vasquez M, Almeida LA, Stoltz AJ, Wijewarnasuriya PS, Brill G, Chen Y, Lee U, Vilela MF, Peterson J, Johnson SM...Elect. Mater. 1995;24:505. 5. Doyle K, Swartz CH, Dinan JH, Myers TH, Brill G, Chen Y, VanMil BL, Wijewarnasuriya P. J. Vac. Sci. Technol. B 2013;31

  13. Surface study of mercury-cadmium-telluride

    Energy Technology Data Exchange (ETDEWEB)

    Lops, V.C.

    1985-01-01

    Single crystals of Hg/sub 1-x/Cd/sub x/Te were studied to determine how changes in the surface conditions affected electrical properties. Infrared detector grade material from Honeywell Radiation Center (x = 0.2, bandgap near 10 ..mu..m) was used to examine the effects of changes in the surface charge density on electrical I/f noise. The surface charge density, which was controlled by the pH of the aqueous solution was measured in a zeta meter that operated much like a Millikan oil-drop experiment. The electrophoresis zeta potential measurements on (HgCd)Te identified the active surface oxide as TeO/sub 2/ and also revealed information on the surface chemistry. An experimental fit yielded the dissociation constant of tellurous acid, which was the result of TeO/sub 2/ combining with H/sub 2/O. The dissociation of tellurous acid was responsible for the measured surface charge densities and the surface chemistry from pH = 1 to pH = 8. At pH = 1, the surface was H/sub 3/TeO/sub 2//sup +/. At pH = 1.5, the surface was H/sub 2/TeO/sub 3/ which gave the neutral point, PZZP (Point of Zero Zeta Potential). With the pH between 2 and 6, the surface was HTeO/sub 3//sup -/. As the pH was changed to 7 and greater, the surface was TeO/sub 3//sup -/. Electrical I/f noise in (HgCd)Te was found to be dominated by bulk and not surface effects at room temperature.

  14. Mercury(1)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    1.Mercury is the planet closest to the sun.It is thefastest moving planet.And it is the second smallestplanet in our solar system. 2.Mercury is very difficult to see.Its orbit isbetween us and the sun.So,we have to look toward thebright light of the sun to see it.The sunlight usuallyhides Mercury.When we can see it,it appears as a fuzzyball.

  15. Mercury(5)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    26. Mercury appears to have a center of iron thattakes up seventy-five percent 0f the planet. There isonly a thin outer covering of rock around the core. Someastronomers think most of Mercury's rock was explodedoff when the planet was hit by a huge object early in itshistory.

  16. Cadmium toxicity to ringed seals (Phoca hispida): an epidemiological study of possible cadmium-induced nephropathy and osteodystrophy in ringed seals (Phoca hispida) from Qaanaaq in Northwest Greenland

    DEFF Research Database (Denmark)

    Sonne-Hansen, C; Dietz, R; Leifsson, P S;

    2002-01-01

    . Experience from cadmium-poisoned humans and laboratory mammals indicates that concentrations above 50-200 microg/g wet wt. may induce histopathological changes. Overall, 31 of the ringed seals had cadmium concentrations in the kidney cortex above 50 microg/g wet wt., 11 had concentrations above 100 and one......The Greenland marine food chains contain high levels of cadmium, mercury and selenium. Concentrations of cadmium in the kidney of ringed seals (Phoca hispida) from the municipalities of Qaanaaq and Upernavik (Northwest Greenland) are among the highest recorded in the Arctic. The purpose...... of the study was to determine whether cadmium-induced damage in the kidneys and the skeletal system could be detected among 100 ringed seals from Northwest Greenland. The cadmium concentrations in the kidney cortex ranged from 0 to 248 microg/g wet weight (mean=44.5, N=100) in the 99 kidneys examined...

  17. Effects on the population dynamics of Brachionus rubens (Rotifera) caused by mercury and cadmium administered through medium and algal food Chlorella vulgaris%在培养基和食料中添加铅和镉对轮虫种群动态的影响

    Institute of Scientific and Technical Information of China (English)

    S.S.S.SARMA; Hilda Fabiola NUNEZ-CRUZ; S.NANDINI

    2005-01-01

    Due to industrial activities,heavy metal concentrations in aquatic systems of Mexico,are on the rise.Zooplankton,particularly rotifers,being sensitive and common components of freshwater,are widely used in ecotoxicological tests for establishing water quality criteria.Depending on the route of exposure (i.e.via medium or algal food),the toxicity of heavy metals varies.In the present study we evaluated the effect of cadmium and mercury exposed through medium and via algal food for the rotifer B.rubens.For both the heavy metals,we exposed rotifers via medium containing Chlorella at 0.5×106 cells/ml or fed daily on previously exposed (1,2 and 4 h) alga to the toxicants (using 5 times the value of LC50 for B.rubens).For cadmium toxicity through medium,we used 3 toxicant levels (0.1,0.2 and 0.4 mg/L) and for mercury,we used 0.005,0.010 and 0.015 mg/L.Based on the LC50,B.rubens was 24 times more sensitive to mercury (0.035±0.002 mg/L) than cadmium.At a concentration of 0.4 mg/L,cadmium through the medium caused increased lag phase of B.rubens.When grown on Chlorella exposed for different durations to cadmium,the rotifer density decreased with the increasing duration of algal exposure to the heavy metal.When mercury was used in the medium or via algal food,the trends in the population growth of B.rubens were similar to those for cadmium.An increase in heavy metal concentration in the medium resulted in a decrease of the rate of population increase per day (r).The r varied from 0.33 (in control) to 0.02 d-1 (in heavy metal treatment) depending on the mode of exposure though medium or via algal food[Acta Zoologica Sinica 51(1):46-52,2005].%由于工业活动的影响,墨西哥水体环境中的重金属浓度在上升.浮游动物,尤其是轮虫类,由于对环境变化十分敏感而且是淡水中的常见组成部分,因此被广泛用于生态毒理试验以确定水质标准.在不同的胁迫途径下(如通过培养基或食料),重金属的毒性是不同的.在

  18. Determination of arsenic, lead, cadmium, chromium, nickel in mainstream smoke of cigarette by graphite furnace atomic absorption spectrometry%石墨炉原子吸收法测定卷烟主流烟气中的砷、铅、镉、铬、镍

    Institute of Scientific and Technical Information of China (English)

    周雯; 许锴霖; 岳勇; 徐海涛; 周仕禄; 汪东风

    2012-01-01

    A method based on graphite furnace atomic absorption spectrometry after microwave digestion for determining arsenic (As), lead (Pb), cadmium (Cd), chromium (Cr) and nickel (Ni) in mainstream smoke of cigarette was developed by optimizing microwave digestion, matrix modifier, ashing temperature and atomic temperature. Under the optimized conditions, the detection limits of the method for As, Pb, Cd, Cr and Ni were 0.008 29, 0.008 12, 0.006 29, 0.006 33 and 0.007 23 μg/L, respectively. The relative standard deviations were 3.14%-4.17% for As, 2.63%-4.12% for Pb, 0.93%-4.45% for Cd, 3.76%-4.29% for Cr and 1.44%-4.87% for Ni. The recoveries of the method for As, Pb, Cd, Cr and Ni were 97.75%-l 15.40%, 83.44%-118.43%, 83.71%-113.05%, 101.72%-107.03% and 93.63%-115.53%, respectively. Cr content was the highest, the content of Pb and Cd were moderate and the contents of Ni and As were the lowest in the main stream smoke of five tested cigarette samples.%通过优化微波消解体系、基体改进剂、灰化温度以及原子化温度,建立了一种微波消解-石墨炉原子吸收法,用于测定卷烟主流烟气中砷、铅、镉、铬、镍的含量.结果表明:该方法对于卷烟主流烟气中砷、铅、镉、铬、镍的检出限为6.29~8.29ng/L,相对标准偏差为0.93%~4.87%,加标回收率分别为83.44%~115.53%,所测5种卷烟样品的主流烟气中,铬含量最高,铅、镉含量居中,镍与砷含量接近,最低.

  19. Determination of lead, arsenic, cadmium, chromium, nickel in sea products by inductively coupled plasma mass spectrometry with microwave digestion%微波消解-电感耦合等离子体质谱测定水产品中铅、砷、镉、铬、镍含量

    Institute of Scientific and Technical Information of China (English)

    解楠; 曹程明; 徐红斌; 葛宇

    2011-01-01

    Inductively coupled plasma mass spectrometry (ICP-MS) with microwave digestion was applied to determine lead,arsenic,cadmium,chromium and nickel in sea products.The linear ranged of the method was from 0 to 200ng/mL,and linear correlation factors for each element were good(r>0.9995).The detection limits were between 0.012 to 0.091 ng/mL Precision was fine,and RSD was lower than 5%,and recoveries of sea products samples were in the range of 86.1%~115.5%.The results showed close agreement with the reference values in three standard reference materials of GBW08571 ,GBW08521 ,GBW07605( GSV-4).lt indicated that the method was simple,sensitive,accurate and short of analytical cycle,which could meet the demand for the determining heavy metal elements in sea products.%研究了同时准确测定的水产品中铅、砷、镉、铬、镍元素方法.采用微波消解仪对样品进行前处理、电感耦合等离子体质谱测定5种元素含量.实验表明,所有元素标准曲线的线性范围均在0~200ng/mL之间,线性方程相关系数(r)均大于0.9995,检出限为0.012~0.091ng/mL,RSD<5%,加标回收率在86.1%~115.5%之间,并以标准物质GBW08571、GBW08521、GBW07605(GSV-4)对方法进行了评价,各元素测定值均在标准值范围之内.该方法具有简单、快速、灵敏、准确的优点,能够对水产品中的重金属元素进行测定.

  20. 2010年-2011年闽北地区农产品重金属铅镉汞污染状况分析%Analysis of heavy metals pollution of lead,cadmium and mercury in agricultural products in northern Fujian from 2010 to 2011

    Institute of Scientific and Technical Information of China (English)

    陈涛; 张曦; 陈大红

    2012-01-01

    Objective: To know the levels of lead, cadmium and mercury in agricultural products in northern Fujian, analyze the reasons of pollution, and then evaluate the food safety. Methods: According to the monitoring task of food contaminant issued by Fujian province, samples of agricultural products were collected from large supermarkets and farmer markets in ten counties and cities of northern Fujian, 462 samples of 12 species were detected to check the proportions of heavy metals (lead, cadmium and mercury ). Results: From 2010 to 2011 , the overall pass rates of lead, cadmium and mercury in 12 kinds of agricultural products were 97.4 % , 95. 6 % and 97. 7 % respectively. In terms of meat, lead -free preserved eggs, fish, dairy products and tea, the passing rates were all 100% ; The lowest pass rate was 33. 3% found in crustaceans. Conclusion: From 2010 to 2011, heavy metal pollution in agricultural products of Nanping region was not serious in general. However, dry edible fungi and crustaceans in the circulation market with serious heavy metal pollution should be improved by appropriate measures, such as reducing coastal water pollution, enhancing aquaculture, plant supervision and management of the industry to ensure the quality and safety of agricultural products.%目的:了解闽北地区农产品中重金属铅、镉、汞的含量水平,分析污染原因,评价其食用安全性.方法:结合省下达的食品污染物监测任务,采集闽北地区十个县市大型超级市场和农贸市场所出售的农产品,共检测12个种类462份样品,测定重金属铅、镉、汞的含量.结果:2010年-2011年我区12种农产品中铅、镉、汞的总体合格率分别达到97.4%、95.6%和97.7%.肉类、无铅皮蛋、鱼类、奶制品和茶叶的总合格率均为100%;甲壳类产品的合格率最低为33.3%.结论:2010年-2011年我区农产品重金属污染状况总体不严重,但流通市场中的干食用菌、甲壳类产品重金属超标

  1. Mercury and Pregnancy

    Science.gov (United States)

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

  2. 40 CFR 437.24 - New source performance standards (NSPS).

    Science.gov (United States)

    2010-07-01

    ... GUIDELINES AND STANDARDS THE CENTRALIZED WASTE TREATMENT POINT SOURCE CATEGORY Oils Treatment and Recovery..., TSS, arsenic, cadmium, chromium, cobalt, copper, lead, mercury, tin, zinc, butylbenzyl...

  3. 40 CFR 437.16 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS THE CENTRALIZED WASTE TREATMENT POINT SOURCE CATEGORY Metals Treatment... standards: Standards for antimony, arsenic, cadmium, chromium, cobalt, copper, lead, mercury, nickel,...

  4. 40 CFR 437.23 - Effluent limitations attainable by the application of the best available technology economically...

    Science.gov (United States)

    2010-07-01

    ... CENTRALIZED WASTE TREATMENT POINT SOURCE CATEGORY Oils Treatment and Recovery § 437.23 Effluent limitations..., cadmium, chromium, cobalt, copper, lead, mercury, tin, zinc, butylbenzyl phthalate, carbazole,...

  5. 40 CFR 437.13 - Effluent limitations attainable by the application of the best available technology economically...

    Science.gov (United States)

    2010-07-01

    ... CENTRALIZED WASTE TREATMENT POINT SOURCE CATEGORY Metals Treatment and Recovery § 437.13 Effluent limitations... antimony, arsenic, cadmium, chromium, cobalt, copper, lead, mercury, nickel, silver, tin,...

  6. 40 CFR 437.15 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

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

  7. Cadmium and zinc relationships.

    Science.gov (United States)

    Elinder, C G; Piscator, M

    1978-08-01

    Cadmium and zinc concentrations in kidney and liver have been measured under different exposure situations in different species including man. The results show that zinc increases almost equimolarly with cadmium in kidney after long-term low-level exposure to cadmium, e.g., in man, horse, pig, and lamb. In contrast, the increase of zinc follows that of cadmium to only a limited extent, e.g., in guinea pig, rabbit, rat, mouse, and chicks. In liver, the cadmium--zinc relationship seems to be reversed in such a way that zinc increases with cadmium more markedly in laboratory animals than in higher mammals. These differences between cadmium and zinc relationships in humans and large farm animals and those in commonly used laboratory animals must be considered carefully before experimental data on cadmium and zinc relationships in laboratory animals can be extrapolated to humans.

  8. Got Mercury?

    Science.gov (United States)

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

    2010-01-01

    Many lamps used in various spacecraft contain elemental mercury, which is efficiently absorbed through the lungs as a vapor. The liquid metal vaporizes slowly at room temperature, but may be completely vaporized when lamps are operating. Because current spacecraft environmental control systems are unable to remove mercury vapors, we considered short-term and long-term exposures. Using an existing study, we estimated mercury vapor releases from lamps that are not in operation during missions lasting less than or equal to 30 days; whereas we conservatively assumed complete vaporization from lamps that are operating or being used during missions lasing more than 30 days. Based on mercury toxicity, the Johnson Space Center's Toxicology Group recommends stringent safety controls and verifications for any hardware containing elemental mercury that could yield airborne mercury vapor concentrations greater than 0.1 mg/m3 in the total spacecraft atmosphere for exposures lasting less than or equal to 30 days, or concentrations greater than 0.01 mg/m3 for exposures lasting more than 30 days.

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

    Science.gov (United States)

    Kolker, Allan; Quick, Jeffrey C.; Senior, Connie L.; Belkin, Harvey E.

    2012-01-01

    Mercury is a toxic pollutant. In its elemental form, gaseous mercury has a long residence time in the atmosphere, up to a year, allowing it to be transported long distances from emission sources. Mercury can be emitted from natural sources such as volcanoes, or from anthropogenic sources, such as coal-fired powerplants. In addition, all sources of mercury on the Earth's surface can re-emit it from land and sea back to the atmosphere, from which it is then redeposited. Mercury in the atmosphere is present in such low concentrations that it is not considered harmful. Once mercury enters the aquatic environment, however, it can undergo a series of biochemical transformations that convert a portion of the mercury originally present to methylmercury, a highly toxic organic form of mercury that accumulates in fish and birds. Many factors contribute to creation of methylmercury in aquatic ecosystems, including mercury availability, sediment and nutrient load, bacterial influence, and chemical conditions. In the United States, consumption of fish with high levels of methylmercury is the most common pathway for human exposure to mercury, leading the U.S. Environmental Protection Agency (EPA) to issue fish consumption advisories in every State. The EPA estimates that 50 percent of the mercury entering the atmosphere in the United States is emitted from coal-burning utility powerplants. An EPA rule, known as MATS (for Mercury and Air Toxics Standards), to reduce emissions of mercury and other toxic pollutants from powerplants, was signed in December 2011. The rule, which is currently under review, specifies limits for mercury and other toxic elements, such as arsenic, chromium, and nickel. MATS also places limits on emission of harmful acid gases, such as hydrochloric acid and hydrofluoric acid. These standards are the result of a 2010 detailed nationwide program by the EPA to sample stack emissions and thousands of shipments of coal to coal-burning powerplants. The United

  10. Chromium and Cadmium Replacement Options for Advanced Aircraft

    Science.gov (United States)

    2003-11-01

    also laser glazing, LISI, etc.) Electrospark deposition (alloying) Localized repair and build-up Explosive cladding Wide area bonding – IDs, gun tubes... deposition Does not seem to cause embrittlement Bath must be dumped periodically Keith Legg, klegg@rowantechnology.com Data available Like EHC...reliability, accuracy Beware – most data will be for heat treated state, but most airframe usage will be as- deposited Wear not as good, corrosion better

  11. Advanced technology for environmentally friendly dry battery. Chikyu ni yasashii kandenchi no kaihatsu (kandenchi no musuigin, mu cadmium ka gijutsu)

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, O.; Miyasaka, K.; Maeda, M. (Toshiba battery Co. Ltd., Tokyo (Japan))

    1992-04-01

    A dry battery was developed that does not contain mercury and cadmium having been used in carbon-zinc batteries and alkaline batteries. This paper describes its summary. Mercury in carbon-zinc batteries is used as a corrosion inhibitor for zinc, and cadmium is used to retain mechanical strength of zinc cans. Surfactants and metal oxides were used as a corrosion inhibitor in place of mercury, added into separators. Magnesium was adopted to substitute cadmiun, and the required mechanical strength was obtained. Mercury in alkaline batteries prevents corrosion in zinc particles (which generated hydrogen gas) and gas generation from impurities (iron and others), and plays roles of improving contacts among zinc particles and suppressing electric resistance low. Discussions were given on zinc alloy composition and corrosion inhibitors to replace the mercury having these roles. For zinc alloy, an alloy using lead with less gas generation and excellent discharge characteristics and bismuth as an added element was adopted. 3 refs., 9 figs.

  12. Cadmium and zinc relationships

    Energy Technology Data Exchange (ETDEWEB)

    Elinder, C.; Piscator, M.

    1978-08-01

    Higher mammals, such as homo sapiens, accumulate zinc in kidney cortex almost equimolarly with cadmium. A different pattern seems to be present in liverthere is a limited increase of zinc in two species of large farm animals compared with a marked increase in the laboratory. In large farm animals, an equimolar increase of zinc with cadmium in renal cortex seems to indicate that the form of metallothionein that binds equal amounts of cadmium and zinc in present. Differences in cadmium and zinc relationships in large animals and humans compared with laboratory animals must be carefully considered. (4 graphs, 26 references)

  13. Groundwater contaminant by hexavalent chromium

    Energy Technology Data Exchange (ETDEWEB)

    Parsons, C. [Univ. of Texas, Austin, TX (United States)

    1995-11-01

    Oxidation of trivalent chromium to hexavalent chromium has been investigated as a function of total manganese in soils as well as various incubation conditions. Chromium and manganese contents were analyzed by atomic absorption (graphite furnace and flame emission respectively) following acid digestion. Total hexavalent chromium generation capacity was determined by addition of 0.001 M CrCL3, incubation, and analysis by s-diphenyl carbazide. Samples were then leached with CaSO{sub 4} and MgSO{sub 4} and incubated in various environments (oven, freeze-drier, field moist, ultrafreeze) to test for geogenic generation of Cr(IV). The degree of geogenic generation of hexavalent chromium was compared with total Mn and Cr content as well as hexavalent generational capacity.

  14. Environmental and health aspects of lighting: Mercury

    Energy Technology Data Exchange (ETDEWEB)

    Clear, R.; Berman, S.

    1993-07-01

    Most discharge lamps, including fluorescent lamps, metal halide lamps, and high pressure sodium lamps, contain Mercury, a toxic chemical. Lighting professionals need to be able to respond to questions about the direct hazards of Mercury from accidentally breaking lamps, and the potential environmental hazards of lamp operation and disposal. We calculated the exposures that could occur from an accidental breakage of lamps. Acute poisoning appears almost impossible. Under some circumstances a sealed environment, such as a space station, could be contaminated enough to make it unhealthy for long-term occupation. Mercury becomes a potential environmental hazard after it becomes methylated. Mercury is methylated in aquatic environments, where it may accumulate in fish, eventually rendering them toxic to people and other animals. Lighting causes Mercury to enter the environment directly from lamp disposal, and indirectly from power plant emissions. The environmental tradeoffs between incandescent and discharge lamps depend upon the amounts released by these two sources, their local concentrations, and their probabilities of being methylated. Indirect environmental effects of lighting also include the release of other heavy metals (Cadmium, Lead and Arsenic), and other air pollutants and carbon dioxide that are emitted by fossil fuel power plants. For a given light output, the level of power plant emissions depends upon the efficacy of the light source, and is thus much larger for incandescent lamps than for fluorescent or discharge lamps. As disposal and control technologies change the relative direct and indirect emissions from discharge and incandescent lamps will change.

  15. ICP-MS法测定减肥茶中铅、汞、镉、砷、铜重金属元素△%Determination of Lead,Mercury,Cadmium,Arsenic,Copper heavy metals in weight-reducing tea by ICP-MS

    Institute of Scientific and Technical Information of China (English)

    吴一兵; 苏建

    2013-01-01

    In this paper,microwave digestion approach to weight-reducing tea samples,with the weight-reducing tea by ICP-MS determination of lead,mercury,cadmium,arsenic,copper heavy metal content.By optimizing the conditions for ICP-MS instrument measured using an internal standard to overcome the instrument drift and sample matrix effects,the establishment of the ICP-MS method for simultaneous determination of many elements in weight-reducing tea.Furthermore, the contamination of heavy metals in severa1 commercial available weight-reducing teas were evaluated which can provide valuable references for the healthy.%  本文采用微波消解方法处理减肥茶样品后,用ICP-MS法测定样品中铅、汞、镉、砷、铜重金属元素的含量,通过优化ICP-MS仪器测定条件,用内标克服仪器信号漂移及样品基体效应等的影响,建立了ICP-MS法同时测定减肥茶中多种元素的方法,同时对市场上不同厂家及不同批次的7例样品重金属的污染状况进行了评估,为健康安全使用减肥茶提供有益参考。

  16. Cation exchange for mercury and cadmium of xanthated, sulfonated, activated and non-treated subbituminous coal, commercial activated carbon and commercial synthetic resin:effect of pre-oxidation on xanthation of subbituminous coal

    Institute of Scientific and Technical Information of China (English)

    Lewis M. Gomez; Fredy Colpas-Castillo; Roberto Fernandez-Maestre

    2014-01-01

    A subbituminous coal was oxidized with air at 150 ?C on a fixed bed for 4 h and xanthated with carbon disulfide in a basic solution, at 30 or 5–10 ?C. This xanthated coal was evaluated for the removal of Hg2? and Cd2? from 7,000 mg/L aqueous solutions; metal concentrations were determined by atomic absorption spectrometry. The ion exchange of the xanthated coal was compared against those of the original subbituminous coal, a sulfonated subbituminous coal, activated carbon, commercial activated carbon, and commercial synthetic resin. The commercial synthetic resin showed the highest exchange capacity (concentration factor 98%) followed by the xanthated coal (concentration factor 96%). The retention of cadmium on the sulfonated subbituminous coal was lower (exchange capacity 0.56 meq/g) than that of xanthated coals (1.85 ± 0.09 meq/g). Our xanthated coal showed a better Cd2? removal (81%against 15%) than a non preoxidized 40-h-xanthated coal, which shows that oxidation of coal increased the amount of oxygenated groups which enhanced xanthation.

  17. Zinc and cadmium monosalicylates

    Energy Technology Data Exchange (ETDEWEB)

    Kharitonov, Yu.Ya.; Tujebakhova, Z.K. (Moskovskij Khimiko-Tekhnologicheskij Inst. (USSR))

    1984-06-01

    Zinc and cadmium monosalicylates of the composition MSal, where M-Zn or Cd, Sal - twice deprotonated residue of salicylic acid O-HOC/sub 6/H/sub 4/COOH (H/sub 2/Sal), are singled out and characterized. When studying thermograms, thermogravigrams, IR absorption spectra, roentgenograms of cadmium salicylate compounds (Cd(OC/sub 6/H/sub 4/COO) and products of their thermal transformations, the processes of thermal decomposition of the compounds have been characterized. The process of cadmium monosalicylate decomposition takes place in one stage. Complete loss of salicylate acido group occurs in the range of 320-460 deg. At this decomposition stage cadmium oxide is formed. A supposition is made that cadmium complex has tetrahedral configuration, at that, each salicylate group plays the role of tetradentate-bridge ligand. The compound evidently has a polymer structure.

  18. Defense Environmental Restoration Program Annual Report to Congress for Fiscal Year 1988

    Science.gov (United States)

    1989-03-01

    styphnate . Mission-support operations have generated hazardous wastes such as TNT, oils, spent halogenated and nonhalogenated solvents, tetracene...asbestos, tranzite, VOCs, trichloroethylene, sodium orthosilicate, heavy metals ( barium , cadmium, chromium, lead, mercury, silver, beryllium), sul- furic...tetrazine, lead styphnate , lead azide, tetryl, octal, hexavalent chromium, copper, cadmium, lead, mercury, arsenic, nitrobodies, sulfates, and chlorides

  19. On texture formation of chromium electrodeposits

    DEFF Research Database (Denmark)

    Nielsen, Christian Bergenstof; Leisner, Peter; Horsewell, Andy

    1998-01-01

    The microstructure, texture and hardness of electrodeposited hard, direct current (DC) chromium and pulsed reversed chromium has been investigated. These investigations suggest that the growth and texture of hard chromium is controlled by inhibition processes and reactions. Further, it has been...... established that codeposition of Cr2O3 nanoparticles is a general feature of DC chromium electrodeposition....

  20. Cadmium, chroom, lood, zink en arseen in het freatische grondwater van de zandgebieden van Nederland, onder bos en heidevelden

    NARCIS (Netherlands)

    Boumans LJM; Fraters B

    1993-01-01

    Concentrations of chromium, lead, cadmium, zinc and arsenic in shallow groundwater under Dutch acid sandy soils with natural and semi-natural vegetation were analysed in this study. At 156 sites we took 10 samples per site of groundwater from within 5 m below the soil surface. All samples were ana

  1. Cadmium, chroom, lood, zink en arseen in het freatische grondwater van de zandgebieden van Nederland, onder bos en heidevelden

    NARCIS (Netherlands)

    Boumans LJM; Fraters B

    1993-01-01

    Concentrations of chromium, lead, cadmium, zinc and arsenic in shallow groundwater under Dutch acid sandy soils with natural and semi-natural vegetation were analysed in this study. At 156 sites we took 10 samples per site of groundwater from within 5 m below the soil surface. All samples were analy

  2. Interactive effects of selenium and cadmium on mammary tumor development and growth in MMTV-infected female mice. A model study on the roles of cadmium and selenium in human breast cancer.

    Science.gov (United States)

    Schrauzer, G N

    2008-01-01

    Previous studies demonstrated that the age-corrected breast cancer mortalities in different countries are inversely correlated with the per-capita dietary intakes of selenium and directly with the estimated intakes of cadmium, zinc, and chromium, suggesting that the anticarcinogenic properties of selenium are counteracted by these elements. The tumor-preventative effects of selenium and the converse effects zinc and chromium have already been confirmed experimentally in studies with female inbred C3H mice carrying murine mammary tumor virus (MMTV). Using the same model of human breast cancer, it is now demonstrated that cadmium abolishes the cancer-protecting effects of selenium. In addition, cadmium was also found to interact with zinc, copper, and chromium. At 1.4 ppm in the drinking water, cadmium caused a significant depletion of zinc in vital organs such as the liver, which is held responsible for a delay of the appearance of the mammary tumors by 4 months and their slower growth rates relative to the Cd-unexposed controls. The results of the present study are relevant to human breast cancer prevention as selenium counteracts the effects of cadmium.

  3. Mercury contamination extraction

    Science.gov (United States)

    Fuhrmann, Mark; Heiser, John; Kalb, Paul

    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.

  4. Adsorptive stripping voltammetric determination of chromium in gallium.

    Science.gov (United States)

    Palrecha, M M; Mathur, P K

    1997-12-19

    The electroanalytical chemistry of trace metals has progressed strongly with the development of cathodic stripping voltammetry (CSV) preceded by adsorption collection of organic metal complexes. A sensitive method for the determination of trace amount of chromium in gallium is described. Gallium is dissolved in sodium hydroxide containing hydrogen peroxide. The method is based on the catalytic activity of nitrate ions on the reduction of Cr(III)TTHA (triethylene tetramine-N,N,N',N'',N''',N'''-hexaacetic acid) complex. The sensitivity of this method is further improved by adsorption preconcentration of Cr(III)TTHA complex at a hanging mercury drop electrode (HMDE). The Cr(III) formed at the electrode surface by the reduction of Cr(VI), which is present in the bulk solution, is immediately complexed by TTHA. The adsorbed complex is then reduced at a peak potential of - 1.26 V, and the peak height of Cr(III) reduction is measured. The determination limit was restricted by the amount of chromium present in the reagent blank solution. The method is suitable for the determination of chromium at level as low as 0.2 mug g(-1) (with about 50 mg of sample) and a relative standard deviation of 15%.

  5. Effect of air pollution on trees. VIII. Heavy metals in leaves of street trees: lead nickel, chrome, and cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Maeno, M.

    1971-01-01

    The nickel, lead, chromium, and cadmium contents of leaves of plants grown in Tokyo were measured. The nickel content ranged from 7-15 ppm, the lead content from 14-34 ppm, chromium from 4-16 ppm, and cadmium from 0.7-1.3 ppm. Fluctuations in metal contents were most pronounced for paulownia. High contents of nickel, lead, and chromium were found in highly polluted industrial areas. The differences in lead content in industrial areas compared to that in residential and commercial areas was less significant. This was attributed to the contribution of lead in exhaust gases. Correlation coefficients between metal content and insoluble materials adhering to leaves were calculated for individual plants.

  6. Mercury and health care.

    Science.gov (United States)

    Rustagi, Neeti; Singh, Ritesh

    2010-08-01

    Mercury is toxic heavy metal. It has many characteristic features. Health care organizations have used mercury in many forms since time immemorial. The main uses of mercury are in dental amalgam, sphygmomanometers, and thermometers. The mercury once released into the environment can remain for a longer period. Both acute and chronic poisoning can be caused by it. Half of the mercury found in the atmosphere is human generated and health care contributes the substantial part to it. The world has awakened to the harmful effects of mercury. The World Health Organization and United Nations Environmental Programme (UNEP) have issued guidelines for the countries' health care sector to become mercury free. UNEP has formed mercury partnerships between governments and other stakeholders as one approach to reducing risks to human health and the environment from the release of mercury and its compounds to the environment. Many hospitals are mercury free now.

  7. Mercury and health care

    Directory of Open Access Journals (Sweden)

    Rustagi Neeti

    2010-01-01

    Full Text Available Mercury is toxic heavy metal. It has many characteristic features. Health care organizations have used mercury in many forms since time immemorial. The main uses of mercury are in dental amalgam, sphygmomanometers, and thermometers. The mercury once released into the environment can remain for a longer period. Both acute and chronic poisoning can be caused by it. Half of the mercury found in the atmosphere is human generated and health care contributes the substantial part to it. The world has awakened to the harmful effects of mercury. The World Health Organization and United Nations Environmental Programme (UNEP have issued guidelines for the countries′ health care sector to become mercury free. UNEP has formed mercury partnerships between governments and other stakeholders as one approach to reducing risks to human health and the environment from the release of mercury and its compounds to the environment. Many hospitals are mercury free now.

  8. Mercury and health care

    Science.gov (United States)

    Rustagi, Neeti; Singh, Ritesh

    2010-01-01

    Mercury is toxic heavy metal. It has many characteristic features. Health care organizations have used mercury in many forms since time immemorial. The main uses of mercury are in dental amalgam, sphygmomanometers, and thermometers. The mercury once released into the environment can remain for a longer period. Both acute and chronic poisoning can be caused by it. Half of the mercury found in the atmosphere is human generated and health care contributes the substantial part to it. The world has awakened to the harmful effects of mercury. The World Health Organization and United Nations Environmental Programme (UNEP) have issued guidelines for the countries’ health care sector to become mercury free. UNEP has formed mercury partnerships between governments and other stakeholders as one approach to reducing risks to human health and the environment from the release of mercury and its compounds to the environment. Many hospitals are mercury free now. PMID:21120080

  9. Innovative soil treatment process design for removal of trivalent chromium

    Energy Technology Data Exchange (ETDEWEB)

    Stallings, J.H. [Air Force, Wright-Patterson AFB, OH (United States). Aeronautical Systems Center; Durkin, M.E. [Hughes Missile Systems Co., Tucson, AZ (United States)

    1997-12-31

    A soil treatment process has been developed as part of a US Air Force environmental compliance project at Air Force Plant 44, Tucson, AZ for treating soil contaminated with heavy metals including trivalent chromium, cadmium, copper, and nickel. The process was designed to treat a total of 133,000 tons of soil in a 400 ton per day facility. Features of the soil treatment process include physical treatment and separation, and a chemical treatment process of the remaining fines using a hypochlorite leach allowing chromium to be solubilized at a high pH. After treating, fines are washed in three stage countercurrent thickeners and chromium hydroxide cake is recovered as a final produce from the leach solution. Treatability studies were conducted, laboratory and a pilot plant was built. Process design criteria and flow sheet, material balances, as well as preliminary equipment selection and sizing for the facility have been completed. Facility was designed for the removal of Cr at a concentration of an average of 1230 mg/kg from the soil and meeting a risk based clean-closure limit of 400 mg/kg of Cr. Capital costs for the 400 tpd plant were estimated at 9.6 million with an operating and maintenance cost of $54 per ton As process is most economic for large quantities of soil with relatively low concentrations of contaminants, it was not used in final closure when the estimated volume of contaminated soil removed dropped to 65,000 tons and concentration of chromium increased up to 4000 mg/kg. However, the process could have application in situations where economics and location warrant.

  10. Mercury Quick Facts: Health Effects of Mercury Exposure

    Science.gov (United States)

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

  11. CHROMIUM STATUS IN DIABETES MELLITUS

    Directory of Open Access Journals (Sweden)

    Keshavarz

    1996-06-01

    Full Text Available Fasting serum chromium, total cholesterol HDL-cholesterol, LDL-cholesterol, triacytglycerot and blood sugar were determined in fifty two diabetic patients with no other organic diseases anil compared with those obtained from a control group including fourty two healthy volunteers matched for age, sex ami body mass irutex (BMI. Fasting serum chromium and HDL-cholesterol were significantly lower in patients than in controls (p<0.0001 and p<0.001 respectively, but the mean triacytglycerot concentration was significantly higher in patients than in controls (p<002. Mean total cholesterol and LDL-cholesterol values were not significantly different in the two groups. Mean intake of energy, proteins, fats and chromium, estimated by the 24 hr dietary recall method were not significantly different in the two groups. We demonstrated that despite an adequate intake of chromium, the fasting serum chromium was lower in diabetic patients than in control subjects. Chromium deficiency in diabetic patients may act as a contributing factor in aggravating the disease's complications.

  12. Cadmium status in Egypt

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    It is inferred from these studies that releases of Cd are still increasing and it is recommended that measures must be taken to reduce emissions of cadmium. Any cadmium discharged into the Egyptian environment may move from one compartment to another at varying rates,resulting in an accumulation in compartments such as soils and biota. Such accumulation can be expected to increase with continued emissions,and attention should be given to all sources of cadmium, natural as well as anthropogenic especially in the industrial cities in Egypt. Cadmium present in sewage, as well as industrial effluent (also, other liquid and solid wastes) and sewage sludge will increase levels in soils and is xpected to contribute to dietary levels and body burdens. The current information indicates that such effects may have to be evaluated over long periods of time, possibly as long as 50 - 100 years.

  13. Mercury (Environmental Health Student Portal)

    Science.gov (United States)

    ... to dispose of (get rid of) mercury and mercury compounds properly, or they can wind up contaminating (polluting) soil, water, and air. Show more What products might have mercury in them? People have used mercury throughout history — ...

  14. Galvanic cells including cobalt-chromium alloys.

    Science.gov (United States)

    Gjerdet, N R

    1980-01-01

    Galvanic cells may be created when dentures made of cobalt-chromium alloys are placed on teeth with metallic restorations. The power of such cells was evaluated in an in vitro galvanic using amalgams, gold alloy, and nickel-chromium alloys. The amalgams and one of the nickel-chromium alloys revealed high corrosion currents when placed in contact with cobalt-chromium alloy, the conventional amalgam showing the highest values. The gold alloy and another nickel-chromium alloy exhibited low corrosion currents and they were noble with respect to cobalt-chromium.

  15. Plausible Mechanisms of Cadmium Carcinogenesis

    Science.gov (United States)

    Cadmium is a transition metal and an ubiquitous environmental and industrial pollutant. Laboratory animal studies and epidemiological studies have shown that exposure to cadmium is associated with various organ toxicities and carcinogenic effects. Several national and internation...

  16. Mechanisms of mercury bioremediation.

    Science.gov (United States)

    Essa, A M M; Macaskie, L E; Brown, N L

    2002-08-01

    Mercury is one of the most toxic heavy metals, and has significant industrial and agricultural uses. These uses have led to severe localized mercury pollution. Mercury volatilization after its reduction to the metallic form by mercury-resistant bacteria has been reported as a mechanism for mercury bioremediation [Brunke, Deckwer, Frischmuth, Horn, Lunsdorf, Rhode, Rohricht, Timmis and Weppen (1993) FEMS Microbiol. Rev. 11, 145-152; von Canstein, Timmis, Deckwer and Wagner-Dobler (1999) Appl. Environ. Microbiol. 65, 5279-5284]. The reduction/volatilization system requires to be studied further, in order to eliminate the escape of the metallic mercury into the environment. Recently we have demonstrated three different mechanisms for mercury detoxification in one organism, Klebsiella pneumoniae M426, which may increase the capture efficiency of mercury.

  17. Chromium at High Pressure

    Science.gov (United States)

    Jaramillo, Rafael

    2012-02-01

    Chromium has long served as the archetype of spin density wave magnetism. Recently, Jaramillo and collaborators have shown that Cr also serves as an archetype of magnetic quantum criticality. Using a combination of x-ray diffraction and electrical transport measurements at high pressures and cryogenic temperatures in a diamond anvil cell, they have demonstrated that the N'eel transition (TN) can be continuously suppressed to zero, with no sign of a concurrent structural transition. The order parameter undergoes a broad regime of exponential suppression, consistent with the weak coupling paradigm, before deviating from a BCS-like ground state within a narrow but accessible quantum critical regime. The quantum criticality is characterized by mean field scaling of TN and non mean field scaling of the transport coefficients, which points to a fluctuation-induced reconstruction of the critical Fermi surface. A comparison between pressure and chemical doping as means to suppress TN sheds light on different routes to the quantum critical point and the relevance of Fermi surface nesting and disorder at this quantum phase transition. The work by Jaramillo et al. is broadly relevant to the study of magnetic quantum criticality in a physically pure and theoretically tractable system that balances elements of weak and strong coupling. [4pt] [1] R. Jaramillo, Y. Feng, J. Wang & T. F. Rosenbaum. Signatures of quantum criticality in pure Cr at high pressure. Proc. Natl. Acad. Sci. USA 107, 13631 (2010). [0pt] [2] R. Jaramillo, Y. Feng, J. C. Lang, Z. Islam, G. Srajer, P. B. Littlewood, D. B. McWhan & T. F. Rosenbaum. Breakdown of the Bardeen-Cooper-Schrieffer ground state at a quantum phase transition. Nature 459, 405 (2009).

  18. Chromium Salen Mediated Alkene Epoxidation

    DEFF Research Database (Denmark)

    Petersen, Kaare Brandt; Norrby, Per-Ola; Daly, Adrian M.;

    2002-01-01

    The mechanism of alkene epoxidation by chromium(v) oxo salen complexes has been studied by DFT and experimental methods. The reaction is compared to the closely related Mn-catalyzed process in an attempt to understand the dramatic difference in selectivity between the two systems. Overall......, the studies show that the reactions have many similarities, but also a few critical differences. In agreement with experiment, the chromium system requires a change from low- to high-spin in the catalytic cycle, whereas the manganese system can proceed either with spin inversion or entirely on the high......-spin surface. The low-spin addition of metal oxo species to an alkene leads to an intermediate which forms epoxide either with a barrier on the low-spin surface or without a barrier after spin inversion. Supporting evidence for this intermediate was obtained by using vinylcyclopropane traps. The chromium...

  19. Cadmium determination in Lentinus edodes mushroom species

    Directory of Open Access Journals (Sweden)

    Vera Akiko Maihara

    2012-09-01

    Full Text Available Many studies have drawn attention to the occurrence and concentration of toxic elements found in the fruiting body of mushrooms. Some edible mushroom species are known to accumulate high levels of inorganic contaminants, mainly cadmium, mercury, and lead. There are about 2,000 known edible mushroom species, but only 25 of them are cultivated and used as food. In Brazil, the most marketed and consumed mushroom species are Agaricus bisporus, known as Paris champignon, Lentinus edodes, or Shitake and Pleurotus sp, also called Shimeji or Hiratake. In this study, the concentration of cadmium was determined in Lentinus edodes mushrooms from different cities in São Paulo state and some samples imported from Japan and China. The analyses were performed by graphite furnace atomic absorption spectrometry after HNO3-H2O2 digestion. The results showed a lower concentration of Cd in the mushrooms cultivated in São Paulo (0.0079 to 0.023 mg.kg-1 in natura than that of the mushrooms cultivated abroad (0.125 to 0.212 mg.kg-1 in natura. Although there is no tolerance limit for Cd in mushrooms in Brazil, the results show that Lentinus edodes mushrooms can be safely consumed.

  20. Collinear laser spectroscopy of atomic cadmium

    CERN Document Server

    Frömmgen, Nadja; Bissell, Mark L; Bieroń, Jacek; Blaum, Klaus; Cheal, Bradley; Flanagan, Kieran; Fritzsche, Stephan; Geppert, Christopher; Hammen, Michael; Kowalska, Magdalena; Kreim, Kim; Krieger, Andreas; Neugart, Rainer; Neyens, Gerda; Rajabali, Mustafa M; Nörtershäuser, Wilfried; Papuga, Jasna; Yordanov, Deyan T

    2015-01-01

    Hyperfine structure $A$ and $B$ factors of the atomic $5s\\,5p\\,\\; ^3\\rm{P}_2 \\rightarrow 5s\\,6s\\,\\; ^3\\rm{S}_1$ transition are determined from collinear laser spectroscopy data of $^{107-123}$Cd and $^{111m-123m}$Cd. Nuclear magnetic moments and electric quadrupole moments are extracted using reference dipole moments and calculated electric field gradients, respectively. The hyperfine structure anomaly for isotopes with $s_{1/2}$ and $d_{5/2}$ nuclear ground states and isomeric $h_{11/2}$ states is evaluated and a linear relationship is observed for all nuclear states except $s_{1/2}$. This corresponds to the Moskowitz-Lombardi rule that was established in the mercury region of the nuclear chart but in the case of cadmium the slope is distinctively smaller than for mercury. In total four atomic and ionic levels were analyzed and all of them exhibit a similar behaviour. The electric field gradient for the atomic $5s\\,5p\\,\\; ^3\\mathrm{P}_2$ level is derived from multi-configuration Dirac-Hartree-Fock calculatio...

  1. Environmental biochemistry of chromium.

    Science.gov (United States)

    Losi, M E; Amrhein, C; Frankenberger, W T

    1994-01-01

    Chromium is a d-block transitional element with many industrial uses. It occurs naturally in various crustal materials and is discharged to the environment as industrial waste. Although it can occur in a number of oxidation states, only 3+ and 6+ are found in environmental systems. The environmental behavior of Cr is largely a function of its oxidation state. Hexavalent Cr compounds (mainly chromates and dichromates) are considered toxic to a variety of terrestrial and aquatic organisms and are mobile in soil/water systems, much more so than trivalent Cr compounds. This is largely because of differing chemical properties: Hexavalent Cr compounds are strong oxidizers and highly soluble, while trivalent Cr compounds tend to form relatively inert precipitates at near-neutral pH. The trivalent state is generally considered to be the stable form in equilibrium with most soil/water systems. A diagram of the Cr cycle in soils and water is given in Fig. 6 (Bartlett 1991). This illustration provides a summary of environmentally relevant reactions. Beginning with hexavalent Cr that is released into the environment as industrial waste, there are a number of possible fates, including pollution of soil and surface water and leaching into groundwater, where it may remain stable and, in turn, can be taken up by plants or animals, and adsorption/precipitation, involving soil colloids and/or organic matter. Herein lies much of the environmental concern associated with the hexavalent form. A portion of the Cr(VI) will be reduced to the trivalent form by inorganic electron donors, such as Fe2+ and S2-, or by bioprocesses involving organic matter. Following this conversion, Cr3+ can be expected to precipitate as oxides and hydroxides or to form complexes with numerous ligands. This fraction includes a vast majority of global Cr reserves. Soluble Cr3+ complexes, such as those formed with citrate, can undergo oxidation when they come in contact with manganese dioxide, thus reforming

  2. Evaluation of Heavy Metal Chromium Pollution Problems and Results in the Production Process of Tradi-tional Chinese Medicines%中药粉碎前后重金属铬含量检测分析

    Institute of Scientific and Technical Information of China (English)

    曾秋初; 李衡; 刘建存; 张铁辉

    2016-01-01

    Objective:To prove the production process( pulverzation processing) by stainless steel pharmaceutical machines of tra-ditional Chinese medicines, including various batches of raw materials, decoction pieces, patent drugs and medicinal subsidiary materi-als, lead to heavy metal chromium exceed the standard. Methods:According to ChP 2010 version Vol 1 appendixⅨB“lead, cad-mium, arsenic, mercury, copper determination method”, referring to ChP 2010 version Vol 2 gelatin capsules “chrome check stand-ard”. Results:Most of the test data showed that the chromium content of the sample exceeded the standard in varying degrees. Con-clusion:Pharmaceutical machinery and equipment using stainless steel lead to chromium exceed the standard in Chinese medicine pro-duction process, bring hidden trouble to the quality of the products.%目的::通过对多批次样品(包括中药材、中药饮片、中成药、药用辅料)粉碎前后的铬含量检测,证明通过不锈钢材质制药机械进行中药细粉加工将导致产品重金属铬超标。方法:参照《中国药典》2010年版一部附录Ⅸ B铅、镉、砷、汞、铜测定法,参考《中国药典》2010年版二部明胶空心胶囊“铬”[检查]标准。结果:大部分检验数据显示,样品的铬含量不同程度超标。结论:使用不锈钢材质的制药机械设备会导致中药生产过程中铬超标,给产品质量带来安全隐患。

  3. [Chronic occupational metallic mercurialism].

    Science.gov (United States)

    Faria, Marcília de Araújo Medrado

    2003-02-01

    This is a review on current knowledge of chronic occupational mercurialism syndrome. Major scientific studies and reviews on clinical manifestation and physiopathology of mercury poisoning were evaluated. The search was complemented using Medline and Lilacs data. Erethism or neuropsychological syndrome, characterized by irritability, personality change, loss of self-confidence, depression, delirium, insomnia, apathy, loss of memory, headaches, general pain, and tremors, is seen after exposure to metallic mercury. Hypertension, renal disturbances, allergies and immunological conditions are also common. Mercury is found in many different work processes: industries, gold mining, and dentistry. As prevention measures are not often adopted there is an increasing risk of mercury poisoning. The disease has been under diagnosed even though 16 clinical forms of mercury poisoning are described by Brazilian regulations. Clinical diagnosis is important, especially because abnormalities in the central nervous, renal and immunological systems can be detected using current medical technology, helping to develop the knowledge and control measures for mercurialism.

  4. The use of trivalent chromium bath to obtain a solar selective black chromium coating

    Science.gov (United States)

    Survilienė, S.; Češūnienė, A.; Juškėnas, R.; Selskienė, A.; Bučinskienė, D.; Kalinauskas, P.; Juškevičius, K.; Jurevičiūtė, I.

    2014-06-01

    Black chromium coatings were electrodeposited from a trivalent chromium bath using a ZnO additive as a second main component. Black chromium was electrodeposited on steel and copper plates and substrates plated with bright nickel prior to black chromium electrodeposition. The black chromium coatings were characterized by XRD and SEM. The XRD data suggest that the phase structure of black chromium may be defined as a zinc solid solution in chromium or a chromium solid solution in zinc depending on the chromium/zinc ratio in the deposit. The role of substrate finish was evaluated through the corrosion resistance and reflectance of black chromium. According to corrosion tests the samples plated with bright nickel prior to black chromium deposition have shown the highest corrosion resistance. The electrodeposited black chromium possesses good optical properties for the absorption of solar energy. The absorption coefficient of black chromium was found to be over 0.99 for the samples obtained without the Ni undercoat and below 0.99 for those obtained with the use of Ni undercoat. However, the use of nickel undercoat before black chromium plating is recommended because it remarkably improves the corrosion resistance of samples.

  5. 29 CFR 1910.1027 - Cadmium.

    Science.gov (United States)

    2010-07-01

    ... battery Plate making, plate preparation 50 All other processes 15 Zinc/Cadmium refining* Cadmium refining... as an airborne concentration of cadmium of 2.5 micrograms per cubic meter of air (2.5 µg/m3... air cadmium level to which an employee is exposed means the exposure to airborne cadmium that...

  6. Acute toxicity and toxic interaction of chromium and nickel to common guppy Poecilia reticulata (Peters)

    Energy Technology Data Exchange (ETDEWEB)

    Khangarot, B.S.; Ray, P.K. (Industrial Toxicology Research Centre, Lucknow (India))

    1990-06-01

    The acute toxicity of heavy metals in combination to the common guppy has been reported. Information on the combined effects of chromium and nickel to fish is rather scarce. Toxicity of nickel and chromium to fish is generally low. These two elements are usually less toxic than silver, cadmium, copper and thallium; depending on test conditions, these may also be less hazardous than zinc, lead and arsenic. The present study was undertaken to investigate the acute toxicity of Ni and Cr singly and the toxic interaction of these two metal ions on survival of the common guppy, Poecilia reticulata (Peters). This species was selected for static bioassays because it can be easily cultured and raised under laboratory conditions through a complete life cycle, and it is one of the most common fish used for laboratory toxicity studies.

  7. Cadmium - is it hazardous

    Energy Technology Data Exchange (ETDEWEB)

    Zartner-Nyilas, G.; Valentin, H.; Schaller, K.H.; Schiele, R.

    1983-01-01

    The report summarizes the state of knowledge and experience on cadmium. Biological, toxicological and epidemiological data have been evaluated. Cd pollution of the environment is reviewed under the aspect of human health. Uptake in food, threshod values of Cd exposure of the population, types and extent of health hazards, possible carcinogenic effects and future fields of research are discussed.

  8. Cadmium and cancer.

    Science.gov (United States)

    Hartwig, Andrea

    2013-01-01

    Cadmium is an established human and animal carcinogen. Most evidence is available for elevated risk for lung cancer after occupational exposure; however, associations between cadmium exposure and tumors at other locations including kidney, breast, and prostate may be relevant as well. Furthermore, enhanced cancer risk may not be restricted to comparatively high occupational exposure, but may also occur via environmental exposure, for example in areas in close proximity to zinc smelters. The underlying mechanisms are still a matter of manifold research activities. While direct interactions with DNA appear to be of minor importance, elevated levels of reactive oxygen species (ROS) have been detected in diverse experimental systems, presumably due to an inactivation of detoxifying enzymes. Also, the interference with proteins involved in the cellular response to DNA damage, the deregulation of cell growth as well as resistance to apoptosis appears to be involved in cadmium-induced carcinogenicity. Within this context, cadmium has been shown to disturb nucleotide excision repair, base excision repair, and mismatch repair. Particularly sensitive targets appear to be proteins with zinc-binding structures, present in DNA repair proteins such as XPA, PARP-1 as well as in the tumor suppressor protein p53. Whether or not these interactions are due to displacement of zinc or due to reactions with thiol groups involved in zinc complexation or in other critical positions under realistic exposure conditions remains to be elucidated. Further potential mechanisms relate to the interference with cellular redox regulation, either by enhanced generation of ROS or by reaction with thiol groups involved in the regulation of signaling pathways. Particularly the combination of these multiple mechanisms may give rise to a high degree of genomic instability evident in cadmium-adapted cells, relevant not only for tumor initiation, but also for later steps in tumor development.

  9. Mercury Calibration System

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-03-11

    U.S. Environmental Protection Agency (EPA) Performance Specification 12 in the Clean Air Mercury Rule (CAMR) states that a mercury CEM must be calibrated with National Institute for Standards and Technology (NIST)-traceable standards. In early 2009, a NIST traceable standard for elemental mercury CEM calibration still does not exist. Despite the vacature of CAMR by a Federal appeals court in early 2008, a NIST traceable standard is still needed for whatever regulation is implemented in the future. Thermo Fisher is a major vendor providing complete integrated mercury continuous emissions monitoring (CEM) systems to the industry. WRI is participating with EPA, EPRI, NIST, and Thermo Fisher towards the development of the criteria that will be used in the traceability protocols to be issued by EPA. An initial draft of an elemental mercury calibration traceability protocol was distributed for comment to the participating research groups and vendors on a limited basis in early May 2007. In August 2007, EPA issued an interim traceability protocol for elemental mercury calibrators. Various working drafts of the new interim traceability protocols were distributed in late 2008 and early 2009 to participants in the Mercury Standards Working Committee project. The protocols include sections on qualification and certification. The qualification section describes in general terms tests that must be conducted by the calibrator vendors to demonstrate that their calibration equipment meets the minimum requirements to be established by EPA for use in CAMR monitoring. Variables to be examined include linearity, ambient temperature, back pressure, ambient pressure, line voltage, and effects of shipping. None of the procedures were described in detail in the draft interim documents; however they describe what EPA would like to eventually develop. WRI is providing the data and results to EPA for use in developing revised experimental procedures and realistic acceptance criteria based on

  10. Far Infrared Mercury-Cadmium-Telluride Photoconductive Detectors.

    Science.gov (United States)

    1980-09-01

    mobl come, v~r, donipŕ Sh totmid c clmtui Mistime Imduileg Uhwtksj-bmd ,wmblund.. and imeelty 5 value of 0.4 us. Below 30 K the lifetime increases...Laboratories), 2) D. L. Smith (California Institute of Technology ), 3) P. M. Raccah (University of Illinois at Chicago Circle), 4) R. E. Longshore (Night

  11. CADMIUM, LEAD AND MERCURY CONTENTS IN FISHES – CASE STUDY

    Directory of Open Access Journals (Sweden)

    Radovan Stanovič

    2012-02-01

    Full Text Available Fish meat is a perfect foodstuff which is up to standard of rational nourishment. It is source of healthy and good digestible material rich on proteins, minerals and vitamins. Fish muscles especially back and lateral muscles are the most important parts of fish organism consumed for escellent chemical composition. Proteins in fish meat are rich on high aminoacids content. The content of fish fat is usually low with the high proportion of unsaturated fatty acids. Also minerals and B, A and D vitamins are very important components of this foodstuff. According to rational nourishment the fish meat should be consumed minimal 2 times weekly. Our research was focused on analysis of bottomn sediments in water reservoir Kolinany from the aspect of Cd, Hg and Pb contents, the determination of observed heavy metal contents in different parts of carp body and the evaluation of hygienic status and suitability of fish meat for the human consumption. Our results have confirmed the hygienic wholesomeness of bottom sediments in water reservoir Kolinany. The Cd, Pb and Hg contents in sediments represent no risk of their input into the fish organisms. The Cd content in fish meat was lower than maximal available amount given by legislative norms, but in selected parts of fish organism such as skin, gills and fins the Cd hygienic limit is 2.9 – 6.6 times exceeded. The Pb content in fish meat was under the hygienic limit, however in skin, gills and fins the content of this heavy metal was 1.31- 2.64 higher than maximal legislative given value. Fish skin, gills and fins belong to the non cosumed parts of fish body by people. The Hg content in fish meat was also lower than hygienc limit. The highest Hg content was observed in fish muscles (0.0544 mg.kg-1 and the lowest one in fish gonads (0.0058 mg.kg-1. The results of Cd, Pb and Hg content determination in carp body confirmed that fish muscles belong to suitable foodstuffs for the human consumption.

  12. Theoretical Investigation of Point Defects of Mercury Cadmium Telluride.

    Science.gov (United States)

    1985-11-01

    J.C. Phillips and L. Kleinman , Phys. Rev. 116, 287(1959). 46. B.J. Austin, V. Heine, and L.J. Sham, "General theory of pseudopotentials," Phys, Rev. 127...R.A. Logan, and J.R. Arthur ,Jr., "The lower conduction band structure of (AI,Ga)As," Inst. Phys. Conf. Ser. No. 33a, 210(1977). 82.M.H. Weiler

  13. Laser induced damage studies in mercury cadmium telluride

    Science.gov (United States)

    Garg, Amit; Kapoor, Avinashi; Tripathi, K. N.; Bansal, S. K.

    2007-10-01

    We have investigated laser induced damage at 1.06 μm laser wavelength in diamond paste polished (mirror finish) and carborundum polished Hg0.8Cd0.2Te (MCT) samples with increasing fluence as well as number of pulses. Evolution of damage morphology in two types of samples is quite different. In case of diamond paste polished samples, evolution of damage morphological features is consistent with Hg evaporation with transport of Cd/Te globules towards the periphery of the molten region. Cd/Te globules get accumulated with successive laser pulses at the periphery indicating an accumulation effect. Real time reflectivity (RTR) measurement has been done to understand melt pool dynamics. RTR measurements along with the thermal profile of the melt pool are in good agreement with thermal melting model of laser irradiated MCT samples. In case of carborundum polished samples, laser damage threshold is significantly reduced. Damage morphological features are significantly influenced by surface microstructural condition. From comparison of the morphological features in the two cases, it can be inferred that laser processing of MCT for device applications depends significantly on surface preparation conditions.

  14. A surface study of mercury-cadmium-telluride

    Science.gov (United States)

    Lopes, V. C.

    1985-12-01

    Single crystals of Hg (sub 1-x) Cd (sub x) Te were studied to determine how changes in the surface conditions affected electrical properties, infrared detector grade material was used to examine the effects of changes in the surface charge density on electrical l/f noise. The surface charge density which was controlled by the pH of the aqueous solution was measured in a zeta meter which operated much like a Millikan oil drop experiment. The electrophoresis zeta potential measurements on (HgCd)Te have identified the active surface oxide as TeO2 and has also revealed information on the surface chemistry. Electrical l/f noise in-(HgCd)Te was found to be dominated by bulk and not surface effects at room temperature. Laser Raman and Auger spectroscopy were used to assess mechanical surface damage and anodic oxide composition.

  15. a Surface Study of Mercury-Cadmium Telluride.

    Science.gov (United States)

    Lopes, Vincent C.

    Single crystals of Hg(,1-x)Cd(,x)Te were studied to determine how changes in the surface conditions affected electrical properties. Infrared detector grade material from Honeywell Radiation Center (x = 0.2, bandgap near 10(mu)m) was used to examine the effects of changes in the surface charge density on electrical l/f noise. The surface charge density which was controlled by the pH of the aqueous solution was measured in a zeta meter which operated much like a Millikan oil drop experiment. The electrophoresis zeta potential measurements on (HgCd)Te have identified the active surface oxide as TeO(,2) and has also revealed information on the surface chemistry. An experimental fit yielded the dissociation constant of tellurous acid which was the result of TeO(,2) combining with H(,2)O. The dissociation of tellurous acid was responsible for the measured surface charge densities and the surface chemistry from pH = 1 to pH = 8. At pH = 1, the surface was H(,3)TeO(,3)('+). At pH = 1.5, the surface was H(,2)TeO(,3) which gave the neutral point, PZZP (Point of Zero Zeta Potential). With the pH between 2 and 6, the surface was HTeO(,3)('-). As the pH was changed to 7 and greater, the surface was TeO(,3)-. Electrical l/f noise in (HgCd)Te was found to be dominated by bulk and not surface effects at room temperature. l/f noise measure- ments were made in an air ambient and in various electrolytic solu- tions which produced different surface charge conditions. The l/f noise voltage did not change within experimental error as the surface charge density was changed (due to major changes in the surface chemistry) by pH; at pH = 7, ((sigma)(,s) = -3 x 10('12) e/cm('2) due to TeO(,3)-), with the pH between 2 and 6 (-1 x 10('12) e/cm('2) < (sigma)(,s) < -2 x 10('12) e/cm('2) due to HTeO(,3)('-)), and to pH = 1.5 ((sigma)(,s) = 0 due to H(,2)TeO(,3)). Laser Raman and Auger spectroscopy were used to assess mechanical surface damage and anodic oxide composition. Surface damage on (HgCd)Te produced dramatic changes in the Raman spectrum which was restored to its pre-damaged state by use of the bromine-methanol etch. Auger spectroscopy of anodically oxidized (HgCd)Te further confirmed that the tellurium surface oxide was TeO(,2). The ratio of the atomic concentrations of Te to O in the oxide was found to be approximately 1 to 2.

  16. Simultaneous determination of chromium(III) and chromium(VI) in aqueous solutions by ion chromatography and chemiluminescence detection

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Jøns, O; Nielsen, B

    1992-01-01

    A method for the simultaneous determination of chromium(iii) and chromium(vi) in a flow system based on chemiluminescence was developed. A Dionex cation-exchange guard column was used to separate chromium(iii) from chromium(vi), and chromium(vi) was reduced by potassium sulfite, whereupon both...

  17. Cadmium in Sweden - environmental risks

    Energy Technology Data Exchange (ETDEWEB)

    Parkman, H.; Iverfeldt, Aa. [Swedish Environmental Research Inst. (Sweden); Borg, H.; Lithner, G. [Stockholm Univ. (Sweden). Inst. for Applied Environmental Research

    1998-03-01

    This report aims at assessing possible effects of cadmium in the Swedish environment. Swedish soils and soft freshwater systems are, due to a generally poor buffering capacity, severely affected by acidification. In addition, the low salinity in the Baltic Sea imply a naturally poor organism structure, with some important organisms living close to their limit of physiological tolerance. Cadmium in soils is mobilized at low pH, and the availability and toxicity of cadmium in marine systems are enhanced at low salinity. The Swedish environment is therefore extra vulnerable to cadmium pollution. The average concentrations of cadmium in the forest mor layers, agricultural soils, and fresh-waters in Sweden are enhanced compared to `back-ground concentrations`, with a general increasing trend from the north to the south-west, indicating strong impact of atmospheric deposition of cadmium originating from the central parts of Europe. In Swedish sea water, total cadmium concentrations, and the fraction of bio-available `free` cadmium, generally increases with decreasing salinity. Decreased emissions of cadmium to the environment have led to decreasing atmospheric deposition during the last decade. The net accumulation of cadmium in the forest mor layer has stopped, and even started to decrease. In northern Sweden, this is due to the decreased deposition, but in southern Sweden the main reason is increased leakage of cadmium from the topsoil as a consequence of acidification. As a result, cadmium in the Swedish environments is undergoing an extended redistribution between different soil compartments, and from the soils to the aquatic systems. 90 refs, 23 figs, 2 tabs. With 3 page summary in Swedish

  18. Renal cadmium overload without nephrotoxicity.

    OpenAIRE

    1981-01-01

    A redundant nickel/cadmium battery worker was investigated for non-specific fatigue after completing five years in the industry. Sensitive techniques for in-vivo organ cadmium measurement showed a moderate accumulation in the liver but a very large concentration in the kidneys. Despite this, overall glomerular and tubular function were not impaired. It was concluded that the mechanism of proteinuria observed in some cadmium workers is obscure and not clearly related to the degree of kidney sa...

  19. Sonoassisted microbial reduction of chromium.

    Science.gov (United States)

    Kathiravan, Mathur Nadarajan; Karthick, Ramalingam; Muthu, Naggapan; Muthukumar, Karuppan; Velan, Manickam

    2010-04-01

    This study presents sonoassisted microbial reduction of hexavalent chromium (Cr(VI)) using Bacillus sp. isolated from tannery effluent contaminated site. The experiments were carried out with free cells in the presence and absence of ultrasound. The optimum pH and temperature for the reduction of Cr(VI) by Bacillus sp. were found to be 7.0 and 37 degrees C, respectively. The Cr(VI) reduction was significantly influenced by the electron donors and among the various electron donors studied, glucose offered maximum reduction. The ultrasound-irradiated reduction of Cr(VI) with Bacillus sp. showed efficient Cr(VI) reduction. The percent reduction was found to increase with an increase in biomass concentration and decrease with an increase in initial concentration. The changes in the functional groups of Bacillus sp., before and after chromium reduction were observed with FTIR spectra. Microbial growth was described with Monod and Andrews model and best fit was observed with Andrews model.

  20. CADMIUM – ENVIRONMENTAL HAZARD

    Directory of Open Access Journals (Sweden)

    Henryka Langauer-Lewowicka

    2010-06-01

    Full Text Available The paper presents some information about current status of cadmium as an environmental health problem. Agricultural uses of phosphate fertilizers, sewage sludge and industrial uses of Cd are the major source of widespread of this metal at trace levels into the general environment and human foodstuffs. It is well known that high cadmium (Cd exposure causes renal damage, anemia, enteropathy, osteoporosis, osteomalacia, whereas the dose-response relationship at low levels exposure is less established. During the last decade an increasing number of studies have found an adverse health effects due to low environmental exposure to Cd. Many authors try to determine the relationship between Cd intake and Cd toxicity indicators, especially dealing renal tubular damage. The level of b2-microglobulin in urine is regarded as the most sensitive biomarker of renal disfunction due to low environmental Cd concentrations.

  1. Peru Mercury Inventory 2006

    Science.gov (United States)

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

    2007-01-01

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

  2. Speciation of Dissolved Cadmium

    DEFF Research Database (Denmark)

    Holm, Peter Engelund; Andersen, Sjur; Christensen, Thomas Højlund

    1995-01-01

    Equilibrium dialysis and ion exchange methods, as well as computer calculations (GEOCHEM), were applied for speciation of dissolved cadmium (Cd) in test solutions and leachate samples. The leachate samples originated from soil, compost, landfill waste and industrial waste. The ion exchange (IE...... leachates showed different Cd speciation patterns as expected. Some leachates were dominated by free divalent Cd (1-70%), some by inorganic complexes (1-87%), and some by organic complexes (7-98%)....

  3. Inoculation of chromium white cast iron

    Directory of Open Access Journals (Sweden)

    D. Kopyciński

    2009-01-01

    Full Text Available It has been proved that an addition of boron carbide introduced as an inoculant to the chromium white cast iron changes the structureof castings. Castings after inoculation revealed a different structure with numerous grains. Primary precipitates of chromium carbide also appeared, reducing the mechanical properties of as-cast parts. Properly established heat treatment regime makes chromium iron castings regain their, originally high, mechanical properties.

  4. A new technology for the treatment of mercury contaminated water and soils.

    Science.gov (United States)

    Zhuang, J M; Walsh, T; Lam, T

    2003-07-01

    A new technology has been developed for the treatment of contaminated water and soils with lignin derivatives. It has been demonstrated that this technology can be used in the process of removal of high levels of mercury from water, and in the immobilization of leachable mercury in contaminated soils. Lignin derivatives contain an abundance of oxygen-containing functional groups such as phenolic, carboxyl, sulfonyl, alcoholic and enolic structures, which will form lignin-metal macromolecular complexes with high stability through ionic and coordinate covalent bonding. This feature is the basis for the application of lignin derivatives in the removal of metal contaminants from water and in the immobilization of leachable metal in soils or sediments. Tests have confirmed that lignin derivatives are capable of combining with a variety of metal ions including chromium, copper, lead, zinc, mercury, nickel and aluminum. In the new water treatment process, lignin derivatives are dissolved in mercury contaminated water to complex mercury in an exceptionally stable form of a lignin-mercury colloid. The lignin-mercury colloid is then coagulated through the addition of a flocculating agent such as ferric chloride. Under optimized conditions, a dean effluent is produced with a residual mercury level of less than 1 microg l(-1), together with a ferric sludge that is not leachable by TCLP, EPA Method 1311. In the new soil stabilization process, a new solid adsorbent of ferric-lignin is blended with mercury contaminated soil. This solid adsorbent can stabilize the soil by complexing with mercury and, thereby, greatly reduce the TCLP mercury of soil.

  5. 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.

  6. Is cadmium hazardous to health. Cadmium - ein Gesundheitsrisiko

    Energy Technology Data Exchange (ETDEWEB)

    Zartner-Nyilas, G.; Valentin, H.; Schaller, K.H.; Schiele, R.

    1983-01-01

    This study entitled ''Is cadmium hazardous to health'' summarizes the current state of knowledge on and experience with cadmium. The authors have made efforts to take into account the more recent literature relating to cadmium. The data evaluated were, especially, biological, toxicological, and epidemiological ones. A principal object was to try to assess the importance of the presence of cadmium in the environment to man. The interest was focused on the uptake of heavy metals with food, danger thresholds for the cadmium exposure of the population, nature and extent of eventual damage to health including possible carcinogenous effects, and suggestions for further points of main emphasis in research. 3 figs., 12 tabs.

  7. Environmental exposure to arsenic and chromium in children is associated with kidney injury molecule-1.

    Science.gov (United States)

    Cárdenas-González, M; Osorio-Yáñez, C; Gaspar-Ramírez, O; Pavković, M; Ochoa-Martínez, A; López-Ventura, D; Medeiros, M; Barbier, O C; Pérez-Maldonado, I N; Sabbisetti, V S; Bonventre, J V; Vaidya, V S

    2016-10-01

    Environmental hazards from natural or anthropological sources are widespread, especially in the north-central region of Mexico. Children represent a susceptible population due to their unique routes of exposure and special vulnerabilities. In this study we evaluated the association of exposure to environmental kidney toxicants with kidney injury biomarkers in children living in San Luis Potosi (SLP), Mexico. A cross-sectional study was conducted with 83 children (5-12 years of age) residents of Villa de Reyes, SLP. Exposure to arsenic, cadmium, chromium, fluoride and lead was assessed in urine, blood and drinking water samples. Almost all tap and well water samples had levels of arsenic (81.5%) and fluoride (100%) above the permissible levels recommended by the World Health Organization. Mean urine arsenic (45.6ppb) and chromium (61.7ppb) were higher than the biological exposure index, a reference value in occupational settings. Using multivariate adjusted models, we found a dose-dependent association between kidney injury molecule-1 (KIM-1) across chromium exposure tertiles [(T1: reference, T2: 467pg/mL; T3: 615pg/mL) (p-trend=0.001)]. Chromium upper tertile was also associated with higher urinary miR-200c (500 copies/μl) and miR-423 (189 copies/μL). Arsenic upper tertile was also associated with higher urinary KIM-1 (372pg/mL). Other kidney injury/functional biomarkers such as serum creatinine, glomerular filtration rate, albuminuria, neutrophil gelatinase-associated lipocalin and miR-21 did not show any association with arsenic, chromium or any of the other toxicants evaluated. We conclude that KIM-1 might serve as a sensitive biomarker to screen children for kidney damage induced by environmental toxic agents.

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

    Science.gov (United States)

    ... the report written? Children attending a daycare in New Jersey were exposed to elemental (metallic) mercury. The ... Mercury is also in some medical and mechanical equipment used in the home and in ... some medical and dental clinics use mercury or items that contain mercury. ...

  9. 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.

  10. 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?

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

    Energy Technology Data Exchange (ETDEWEB)

    Weeks, J.R. [Brookhaven National Lab., Upton, NY (United States)

    1996-06-01

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

  12. Mercury poisoning in wildlife

    Science.gov (United States)

    Heinz, G.H.; Fairbrother, Anne; Locke, Louis N.; Hoff, Gerald L.

    1996-01-01

    Mercury is an intriguing contaminant because it has complex chemical properties, a wide range of harmful effects, and an infinite persistence in the environment. Die-offs of wildlife due to mercury have occurred in many countries, especially before mercury seed dressings were banned. Today, most mercury problems are associated with aquatic environments. Methylmercury, the most toxic chemical form, attacks many organ systems, but damage to the central nervous system is most severe. Harmful wet-weight concentrations of mercury, as methylmercury, in the tissues of adult birds and mammals range from about 8-30 ppm in the brain, 20-60 ppm in liver, 20-60 ppm in kidney, and 15-30 ppm in muscle. Young animals may be more sensitive.

  13. Electrodeposition of chromium from trivalent chromium urea bath containing sulfate and chloride

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The reduction of Cr( Ⅲ) to Cr( Ⅱ ) on copper electrode in trivalent chromium urea bath containing chromium sulfate and chromium chloride as chromium source has been investigated by potentiodynamic sweep. The transfer coefficient α for reduction of Cr( Ⅲ ) to Cr( Ⅱ ) on copper electrode was calculated as 0.46. The reduction is a quasi-reversible process. J-t responses at different potential steps showed that the generation and adsorption characteristics of carboxylate bridged oligomer are relevant to cathode potential. The interface behavior between electrode and solution for Cr( Ⅲ ) complex is a critical factor influencing sustained electrode position of chromium. The hypotheses of the electro-inducing polymerization of Cr( Ⅲ ) was proposed. The potential scope in which sustained chromium deposits can be prepared is from- 1.3 V to- 1.7 V (vs SCE) in the urea bath. Bright chromium deposits with thickness of 30 μm can be prepared in the bath.

  14. Municipal actions to reduce mercury

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-03-15

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

  15. 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…

  16. Cadmium exposure in the Swedish environment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    This report gives a thorough description of cadmium in the Swedish environment. It comprises three parts: Cadmium in Sweden - environmental risks;, Cadmium in goods - contribution to environmental exposure;, and Cadmium in fertilizers, soil, crops and foods - the Swedish situation. Separate abstracts have been prepared for all three parts

  17. Cadmium carcinogenesis – some key points

    OpenAIRE

    2011-01-01

    The article presents briefly the main mechanisms of cadmium carcinogenesis and the most important sites of cancer (lung, breast, prostate, testes, kidney) induced by cadmium. In spite of some evidence showing carcinogenic potential of cadmium, further research is still required to elucidate the relative contributions of various molecular mechanisms involved in cadmium carcinogenesis

  18. Cadmium carcinogenesis – some key points

    Directory of Open Access Journals (Sweden)

    Loreta Strumylaite

    2011-09-01

    Full Text Available The article presents briefly the main mechanisms of cadmium carcinogenesis and the most important sites of cancer (lung, breast, prostate, testes, kidney induced by cadmium. In spite of some evidence showing carcinogenic potential of cadmium, further research is still required to elucidate the relative contributions of various molecular mechanisms involved in cadmium carcinogenesis

  19. 29 CFR 1915.1026 - Chromium (VI).

    Science.gov (United States)

    2010-07-01

    ... system dysfunction; any history of asthma, dermatitis, skin ulceration, or nasal septum perforation; and... is present or is likely to be present from skin or eye contact with chromium (VI), the employer shall... cleaned in a manner that minimizes skin or eye contact with chromium (VI) and effectively prevents...

  20. 29 CFR 1926.1126 - Chromium (VI).

    Science.gov (United States)

    2010-07-01

    ... system dysfunction; any history of asthma, dermatitis, skin ulceration, or nasal septum perforation; and... is present or is likely to be present from skin or eye contact with chromium (VI), the employer shall... cleaned in a manner that minimizes skin or eye contact with chromium (VI) and effectively prevents...

  1. 29 CFR 1910.1026 - Chromium (VI).

    Science.gov (United States)

    2010-07-01

    ... activity involving chromium cannot release dusts, fumes, or mists of chromium (VI) in concentrations at or... currents that prevent the LEVs from performing efficiently. The use of fans has a similar effect. Industry... and positioning of cross drafts, fans, doors, windows, partitions and process equipment that...

  2. Treatment of Mercury Contaminated Oil from Sandia National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Klasson, KT

    2002-05-28

    First Article Tests of a stabilization method for greater than 260 mg mercury/kg oil were performed under a treatability study. This alternative treatment technology will address treatment of U.S. Department of Energy (DOE) organics (mainly used pump oil) contaminated with mercury and other heavy metals. Some of the oil is also co-contaminated with tritium, other radionuclides, and hazardous materials. The technology is based on contacting the oil with a sorbent powder (Self-Assembled Mercaptan on Mesoporous Support, SAMMS), proven to adsorb heavy metals, followed by stabilization of the oil/powder mixture using a stabilization agent (Nochar N990). Two variations of the treatment technology were included in the treatability study. The SAMMS (Self-Assembled Mercaptan on Mesoporous Silica) technology was developed by the Pacific Northwest National Laboratory for removal and stabilization of RCRA metals (i.e., lead, mercury, cadmium, silver, etc.) and for removal of mercury from organic solvents [1]. The SAMMS material is based on self-assembly of functionalized monolayers on mesoporous oxide surfaces. The unique mesoporous oxide supports provide a high surface area, thereby enhancing the metal-loading capacity. SAMMS material has high flexibility in that it binds with different forms of mercury, including metallic, inorganic, organic, charged, and neutral compounds [1] The material removes mercury from both organic wastes, such as pump oils, and from aqueous wastes. Mercury-loaded SAMMS not only passes TCLP tests, but also has good long-term durability as a waste form because: (1) the covalent binding between mercury and SAMMS has good resistance in ion-exchange, oxidation, and hydrolysis over a wide pH range and (2) the uniform and small pore size of the mesoporous silica prevents bacteria from solubilizing the bound mercury. Nochar's N990 Petrobond (Nochar, Inc., Indianapolis, IN) is an oil stabilization agent, specifically formulated for stabilizing vacuum

  3. Study on the adsorption capacity for mercury (Ⅱ) with chromium/cobaIt-doped graphene oxide materiaIs%负载铬钴石墨烯基材料对汞(Ⅱ)的吸附性能研究

    Institute of Scientific and Technical Information of China (English)

    王卓; 邓娟; 朱君妍; 周超; 周晓吉; 郭永福; 白仁碧

    2016-01-01

    The chromium and cobalt doped reduced graphene oxide (RGO/Cr,RGO/Co) composite materials have been synthesized by making use of the reducibility of RGO and the oxidability of transition metallic salts ,and app-lied to the adsorption for Hg2+. The results show that the specific surface area of RGO/Cr is higher than that of RGO/Co and RGO. The hydrophilicity of RGO is effectively improved after having been doped with chromium or cobalt. The theoretical monolayer adsorption capacities of RGO,RGO/Cr and RGO/Co fitting Langmuir model are 128.98,181.86, and 146.86 mg/g,respectively,and the adsorption processes of these three materials complies with the pseudo-first-order and pseudo-second-order kinetic model.%利用石墨烯的还原性与过渡金属盐类的氧化性,制备得到分别负载有铬和钴的还原氧化石墨烯(RGO)复合材料RGO/Cr和RGO/Co,并将其应用于对Hg2+的吸附。结果表明:RGO/Cr比RGO/Co及RGO具有更大比表面积,负载铬和钴后RGO的亲水性能显著增加。 Langmuir拟合RGO、RGO/Cr、RGO/Co对Hg2+的理论单层最大吸附容量分别为128.98、181.86、146.86 mg/g,同时吸附过程均符合伪一级和伪二级动力学模型。

  4. Stripping voltammetric determination of mercury(II) at antimony-coated carbon paste electrode.

    Science.gov (United States)

    Ashrafi, Amir M; Vytřas, Karel

    2011-10-15

    A new procedure was elaborated to determine mercury(II) using an anodic stripping square-wave voltammetry at the antimony film carbon paste electrode (SbF-CPE). In highly acidic medium of 1M hydrochloric acid, voltammetric measurements can be realized in a wide potential window. Presence of cadmium(II) allows to separate peaks of Hg(II) and Sb(III) and apparently catalyses reoxidation of electrolytically accumulated mercury, thus allowing its determination at ppb levels. Calibration dependence was linear up to 100 ppb Hg with a detection limit of 1.3 ppb. Applicability of the method was tested on the real river water sample.

  5. Mercury's Protoplanetary Mass

    CERN Document Server

    Herndon, J M

    2004-01-01

    Major element fractionation among chondrites has been discussed for decades as ratios relative to Si or Mg. Recently, by expressing ratios relative to Fe, I discovered a new relationship admitting the possibility that ordinary chondrite meteorites are derived from two components, a relatively oxidized and undifferentiated, primitive component and a somewhat differentiated, planetary component, with oxidation state like the highly reduced enstatite chondrites, which I suggested was identical to Mercury's complement of lost elements. Here, on the basis of that relationship, I derive expressions, as a function of the mass of planet Mercury and the mass of its core, to estimate the mass of Mercury's lost elements, the mass of Mercury's alloy and rock protoplanetary core, and the mass of Mercury's gaseous protoplanet. Although Mercury's mass is well known, its core mass is not, being widely believed to be in the range of 70-80 percent of the planet mass. For a core mass of 75 percent, the mass of Mercury's lost el...

  6. 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.

  7. Cadmium immobilization by hydroxyapatite

    Directory of Open Access Journals (Sweden)

    Smičiklas Ivana D.

    2003-01-01

    Full Text Available The contamination of air, soil and water by cadmium is a great environmental problem. If cadmium occurs in nature in ionic form, soluble in water, it easily enters into the food chain. Hydroxyapatite (HAP, Ca-o(POAe(OH2 is a sparingly soluble salt and an excellent matrix for the removal of heavy metals from solutions. Considerable research attention has been paid to the bond between Cc/2+ ions and synthetic hydroxyapatite of known composition. The sorption mechanism is complex. The dominant process is ion exchange, but surface adsorption, surface complexation and coprecipitation can also contribute to the overall mechanism. The sorption capacity depends on the characteristics of hydroxyapatite itself and on the experimental conditions. Under optimum conditions a maximum capacity of 0.8 mol Cd2+/mol HAP can be achieved. HAP is a potential sorbent for the remediation of contaminated water and soil, for industrial waste treatment, and it is also referenced as a material that can be used as a barrier around waste depositories.

  8. [Bioremediation of chromium (VI) contaminated site by reduction and microbial stabilization of chromium].

    Science.gov (United States)

    Zheng, Jia-Chuan; Zhang, Jian-Rong; Liu, Xi-Wen; Xu, Qian; Shi, Wei-Lin

    2014-10-01

    Chromium (VI) contaminated soil samples were collected from a chemical plant in Suzhou. Firstly, the reduced soil was prepared by adding reagent (Stone-sulfure reagent) into polluted soil to transfer most chromium (VI) into chromium (III), then a nutrient solution was introduced into the reduced soil, and the stabilized soil was obtained after 60 days culturing. The chromium (VI) content of the three kinds of soil was analyzed. The results showed that the chromium (VI) content in toxicity characteristic leaching liquid (TCLL) dropped by 96. 8% (from 8.26 mg · L(-1) to 0.26 mg · L(-1)), and the total chromium content dropped by 95.7% (from 14.66 mg · L(-1) to 0.63 mg · L(-1)) after bioremediation in 5% nutrient solution. Additionally, the durability of chromium stabilization was tested by potassium permanganate oxidation and sterilization of microbe-treated soil. After oxidation, the chromium (VI) content in TCLL of the reduced soil was increased from 8.26 mg · L(-1) to 14.68 mg · L(-1). However, the content after bioremediation was decreased to 2.68 mg · L(-1). The results of sterilization demonstrated that the death of microbe had no significant effect on the stabilization of chromium. Consequently, the research in this paper demonstrated the feasibility of bioremediation of chromium (VI) polluted soil through reduction followed by stabilization/soilidification, and provided a technique with low cost but high efficiency.

  9. Thallium Mercury Laser Development.

    Science.gov (United States)

    1980-04-17

    AD-A9 840 WESTINGHOUSE RESEARCH AND DEVELOPMENT CENTER PITTSBU--ETC F/A 20/5 THALLIUM MERCURY LASER DEVELOPMENT .(U) APR 80 C S LIU, D W FELDMAN, J L...PACK NO001I78-C-0131 lIlrt A nEQE-WOTFX-R NL THALLIUM MERCURY LASER DEVELOPMENT C. S. Liu, D. W. Feldman and J. L. Pack FINAL REPORT (PHASE II...PERIOD COVERED Thallium Mercury Laser Development -T- Final Report (Phase II) Feb. 1, 1979 to Jan. 31, 1980 77a. w-atF. -REPORT NUMBER _,___C2-OTEX

  10. Determination of Cadmium, Plumbum, Nickel, Copper, Zinc, Chromium, Potassium, Ar senic, Mercury in the Activated Sludge by Atomic Absorption and Atomic Fluoresce nce Spectrometry Digested with Microwave%微波消解-原子吸收/原子荧光光度法测定活性污泥中的Cd、Pb、Ni、Cu、 Zn、Cr、K、As、Hg

    Institute of Scientific and Technical Information of China (English)

    姚国

    2008-01-01

    通过实验,建立了活性污泥中金属和重金属的测定方法. 活性污泥样品经硝酸 - 氢氟酸或硝酸 - 高氯酸微波消解处理后,Pb、Ni、Cu、Zn、Cr、 K选用火焰原子吸收分光光度法测定,Cd用石墨炉原子吸收分光光度法测定,As、Hg用原子荧光光度法测定.该方法操作简单,结果准确,重现性好.样品加标回收率为93%~ 108%,相对标准偏差<5%.

  11. Low-chromium reduced-activation chromium-tungsten steels

    Energy Technology Data Exchange (ETDEWEB)

    Klueh, R.L.; Alexander, D.J.; Maziasz, P.J. [Oak Ridge National Lab., TN (United States)

    1996-10-01

    Bainitic microstructures formed during continuous cooling can differ from classical upper and lower bainite formed during isothermal transformation. Two types of non-classical bainite were observed depending on the cooling rate: carbide-free acicular bainite at rapid cooling rates and granular bainite at slower cooling rates. The Charpy impact toughness of the acicular ferrite was found to be considerably better than for the granular bainite. It was postulated that alloying to improve the hardenability of the steel would promote the formation of acicular bainite, just as increasing the cooling rate does. To test this, chromium and tungsten were added to the 2 1/4Cr-2W and 2 1/4Cr-2WV steel compositions to increase their hardenability, and the microstructures and mechanical properties were examined.

  12. Exposure and effects of metal accumulation by wildlife on Agassiz National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Three topics concerning trace element contamination in wildlife at Agassiz National Wildlife Refuge are summarized below: Cadmium, chromium and mercury...

  13. Epidemiological methods for assessing dose-response and dose-effect relationships

    DEFF Research Database (Denmark)

    Kjellström, Tord; Grandjean, Philippe

    2007-01-01

    of the Toxic Effects of Metals Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Chromium Cobalt Copper Gallium and Semiconductor Compounds Germanium Indium Iron Lead Manganese Mercury Molybdenum Nickel Palladium Platinum Selenium Silver Tellurium Thallium Tin Titanium Tungsten Uranium Vanadium Zinc...

  14. Principles for prevention of toxic effects from metals

    DEFF Research Database (Denmark)

    Landrigan, Philip J.; Kotelchuk, David; Grandjean, Philippe

    2007-01-01

    of the Toxic Effects of Metals Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Chromium Cobalt Copper Gallium and Semiconductor Compounds Germanium Indium Iron Lead Manganese Mercury Molybdenum Nickel Palladium Platinum Selenium Silver Tellurium Thallium Tin Titanium Tungsten Uranium Vanadium Zinc...

  15. Mercury cycling in terrestrial watersheds

    Science.gov (United States)

    Shanley, James B.; Bishop, Kevin; Banks, Michael S.

    2012-01-01

    This chapter discusses mercury cycling in the terrestrial landscape, including inputs from the atmosphere, accumulation in soils and vegetation, outputs in streamflow and volatilization, and effects of land disturbance. Mercury mobility in the terrestrial landscape is strongly controlled by organic matter. About 90% of the atmospheric mercury input is retained in vegetation and organic matter in soils, causing a buildup of legacy mercury. Some mercury is volatilized back to the atmosphere, but most export of mercury from watersheds occurs by streamflow. Stream mercury export is episodic, in association with dissolved and particulate organic carbon, as stormflow and snowmelt flush organic-rich shallow soil horizons. The terrestrial landscape is thus a major source of mercury to downstream aquatic environments, where mercury is methylated and enters the aquatic food web. With ample organic matter and sulfur, methylmercury forms in uplands as well—in wetlands, riparian zones, and other anoxic sites. Watershed features (topography, land cover type, and soil drainage class) are often more important than atmospheric mercury deposition in controlling the amount of stream mercury and methylmercury export. While reductions in atmospheric mercury deposition may rapidly benefit lakes, the terrestrial landscape will respond only over decades, because of the large stock and slow turnover of legacy mercury. We conclude with a discussion of future scenarios and the challenge of managing terrestrial mercury.

  16. Synthesis of Chromium (Ⅲ) 5-aminosalicylate

    Institute of Scientific and Technical Information of China (English)

    LI Wei; HAO Er-jun; JIANG Yu-qin

    2004-01-01

    As we all known that diabetes is a chronic disease with major health consequences.Research has revealed that the occurrence of diabetes have great thing to do with the chromium deficient. Almost 40 years after the first report of glucose tolerance factor(GTF) [1], no conclusive evidence for an isolable ,biologically active form of chromium exited. Three materials have been proposed to be the biologically active form of chromium: "glucose tolerance factor", chromium Picolinate and low-molecular-weight chromium-binding substance (LWMCr) [2] . So there is potential for the design of new chromium drugs .5-Aminosalicylic acid (5-ASA) is identified as an active component in the therapy of inflammatory bowel disease (IBD) such as Crohn's disease and ulcerative colitis . The therapeutic action of 5-ASA is believed to be coupled to its ability to act as a free radical scavenger [3-4],acting locally on the inflamed colonic mucosa [5-7]. However, the clinical use of 5-ASA is limited, since orally administered 5-ASA is rapidly and completely absorbed from the upper gastrointestinal tract and therefore the local therapeutic effects of 5-ASA in the colon is hardly expected.In this paper, we report the synthesis of chromium(Ⅲ)5-aminosalicylate from 5-ASA and CrCl3. 6H2O.The synthesis route is as follow:The complex has been characterized by elemental analysis, IR spectra, X-ray powder diffractionand TG-DTA . They indicate that the structure is tris(5-ASA) Chromium . Experiments show that thecomplex has a good activity for supplement tiny dietary chromium, lowering blood glucose levels,lowering serum lipid levels and in creasing lean body mass .

  17. Characteristics of chromium-allergic dermatitis patients prior to regulatory intervention for chromium in leather

    DEFF Research Database (Denmark)

    Bregnbak, David; Thyssen, Jacob P; Zachariae, Claus;

    2014-01-01

    BACKGROUND: Chromium-tanned leather articles currently constitute the most important cause of contact allergy to chromium in Denmark. A regulation on the content of hexavalent chromium in leather was adopted in November 2013 by the EU member states. OBJECTIVES: To characterize patients...... with chromium allergy and their disease, to serve as a baseline for future studies on the potential effect of the new regulation on chromium in leather. METHODS: A questionnaire case-control study was performed on 155 dermatitis patients with positive patch test reactions to potassium dichromate and a matched...... control group of 621 dermatitis patients. Comparisons were made by use of a χ(2) -test and the Mann-Whitney U-test. Logistic regression analyses were used to test for associations. RESULTS: Sixty-six per cent of chromium-allergic patients had a positive history of contact dermatitis caused by leather...

  18. Chromium in leather footwear-risk assessment of chromium allergy and dermatitis

    DEFF Research Database (Denmark)

    Thyssen, Jacob P; Strandesen, Maria; Poulsen, Pia B;

    2012-01-01

    Background. Chromium-tanned leather footwear, which releases >3 ppm hexavalent Cr(VI), may pose a risk of sensitizing and eliciting allergic dermatitis. Objectives. To determine the content and potential release of chromium in leather footwear and to discuss the prevention of chromium contact...... allergy and dermatitis. Methods. Sixty pairs of leather shoes, sandals and boots (20 children's, 20 men's, and 20 women's) were purchased in Copenhagen and examined with X-ray fluorescence spectroscopy. Chromium was extracted according to the International Standard, ISO 17075. The detection level for Cr......(VI) was 3 ppm. Results. Chromium was identified in 95% of leather footwear products, the median content being 1.7% (range 0-3.3%). No association with store category or footwear category was found. A tendency for there to be a higher chromium content in footwear with high prices was shown (p(trend) = 0...

  19. Leaching of chromium from chromium contaminated soil: Speciation study and geochemical modeling

    Directory of Open Access Journals (Sweden)

    Anđelković Darko H.

    2012-01-01

    Full Text Available Distribution of chromium between soil and leachate was monitored. A natural process of percolating rainwater through the soil was simulated in the laboratory conditions and studied with column leaching extraction. Migration of chromium in the soil is conditioned by the level of chromium soil contamination, the soil organic matter content, and rainwater acidity. Chromium (III and chromium(VI were determined by spectrophotometric method with diphenilcarbazide in acidic media. Comparing the results of chromium speciation in leachate obtained by experimental model systems and geochemical modelling calculations using Visual MINTEQ model, a correlation was observed regarding the influence of the tested parameters. Leachate solutions showed that the concentration of Cr depended on the organic matter content. The influence of pH and soil organic matter content is in compliance after its definition through experimental and theoretical way. The computer model - Stockholm Humic Model used to evaluate the leaching results corresponded rather well with the measured values.

  20. Cadmium effects on the thyroid gland.

    Science.gov (United States)

    Jancic, Snezana A; Stosic, Bojan Z

    2014-01-01

    Cadmium has been listed as one of the 126 priority pollutants and a category I carcinogen. Carcinogenic effects of cadmium on the lungs, testicles, and prostate are widely recognized, but there has been insufficient research on the effect of cadmium on the thyroid gland. Cadmium has the affinity to accumulate not only in the liver, kidneys, and pancreas but also in the thyroid gland. It has been established that cadmium blood concentration correlates positively with its accumulation in the thyroid gland. Women of fertile age have higher cadmium blood and urine concentrations than men. In spite of its redox inertia, cadmium brings about oxidative stress and damage to the tissue by indirect mechanisms. Mitochondria are considered to be the main intracellular targets for cadmium. Colloid cystic goiter, adenomatoid follicular hyperplasia with low-grade dysplasia and thyroglobulin hypo- and asecretion, and parafollicular cell diffuse and nodular hyperplasia and hypertrophy are often found in chronic cadmium toxicity.

  1. 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...

  2. Mercury exposure in Ireland

    DEFF Research Database (Denmark)

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

    2014-01-01

    BACKGROUND: Monitoring of human exposure to mercury is important due to its adverse health effects. This study aimed to determine the extent of mercury exposure among mothers and their children in Ireland, and to identify factors associated with elevated levels. It formed part of the Demonstration...... 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...

  3. Ecosystem conceptual model- Mercury

    Science.gov (United States)

    Alpers, Charles N.; Eagles-Smith, Collin A.; Foe, Chris; Klasing, Susan; Marvin-DiPasquale, Mark C.; Slotton, Darell G.; Windham-Myers, Lisamarie

    2008-01-01

    Mercury has been identified as an important contaminant in the Delta, based on elevated concentrations of methylmercury (a toxic, organic form that readily bioaccumulates) in fish and wildlife. There are health risks associated with human exposure to methylmercury by consumption of sport fish, particularly top predators such as bass species. Original mercury sources were upstream tributaries where historical mining of mercury in the Coast Ranges and gold in the Sierra Nevada and Klamath-Trinity Mountains caused contamination of water and sediment on a regional scale. Remediation of abandoned mine sites may reduce local sources in these watersheds, but much of the mercury contamination occurs in sediments stored in the riverbeds, floodplains, and the Bay- Delta, where scouring of Gold-Rush-era sediment represents an ongoing source.Conversion of inorganic mercury to toxic methylmercury occurs in anaerobic environments including some wetlands. Wetland restoration managers must be cognizant of potential effects on mercury cycling so that the problem is not exacerbated. Recent research suggests that wettingdrying cycles can contribute to mercury methylation. For example, high marshes (inundated only during the highest tides for several days per month) tend to have higher methylmercury concentrations in water, sediment, and biota compared with low marshes, which do not dry out completely during the tidal cycle. Seasonally inundated flood plains are another environment experiencing wetting and drying where methylmercury concentrations are typically elevated. Stream restoration efforts using gravel injection or other reworking of coarse sediment in most watersheds of the Central Valley involve tailings from historical gold mining that are likely to contain elevated mercury in associated fines. Habitat restoration projects, particularly those involving wetlands, may cause increases in methylmercury exposure in the watershed. This possibility should be evaluated.The DRERIP

  4. 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.

  5. Cutaneous mercury granuloma

    OpenAIRE

    Kalpana A Bothale; Mahore, Sadhana D.; 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...

  6. Blood serum mercury test report.

    Science.gov (United States)

    Vandenberge, J; Moodie, A S; Keller, R E

    1977-06-01

    A clinical blood serum mercury test of 111 dentists and auxiliaries revelaed that more than 50% had above normal serum mercury levels. This study showed that there may be a mercury health hazard in some dental environments. Acute mercury poisoning may be corrected simply by removing the cause, but long-term chronic effects are not known. Frequent screening of offices and personnel is advised. Experience reported here indicates that large amounts of mercury vapor are emitted when an amalgam carrier is heated over a flame ot dislodge particles, and also, that water-covered amalgam scrap relesases mercury vapor.

  7. To Mercury dynamics

    Science.gov (United States)

    Barkin, Yu. V.; Ferrandiz, J. M.

    Present significance of the study of rotation of Mercury considered as a core-mantle system arises from planned Mercury missions. New high accurate data on Mercury's structure and its physical fields are expected from BepiColombo mission (Anselmi et al., 2001). Investigation of resonant rotation of Mercury, begun by Colombo G. (1966), will play here main part. New approaches to the study of Mercury dynamics and the construction of analytical theory of its resonant rotation are suggested. Within these approaches Mercury is considered as a system of two non-spherical interacting bodies: a core and a mantle. The mantle of Mercury is considered as non-spherical, rigid (or elastic) layer. Inner shell is a liquid core, which occupies a large ellipsoidal cavity of Mercury. This Mercury system moves in the gravitational field of the Sun in resonant traslatory-rotary regime of the resonance 3:2. We take into account only the second harmonic of the force function of the Sun and Mercury. For the study of Mercury rotation we have been used specially designed canonical equations of motion in Andoyer and Poincare variables (Barkin, Ferrandiz, 2001), more convenient for the application of mentioned methods. Approximate observational and some theoretical evaluations of the two main coefficients of Mercury gravitational field J_2 and C22 are known. From observational data of Mariner-10 mission were obtained some first evaluations of these coefficients: J_2 =(8± 6)\\cdot 10-5(Esposito et al., 1977); J_2 =(6± 2)\\cdot 10-5and C22 =(1.0± 0.5)\\cdot 10-5(Anderson et al., 1987). Some theoretical evaluation of ratio of these coefficients has been obtained on the base of study of periodic motions of the system of two non-spherical gravitating bodies (Barkin, 1976). Corresponding values of coefficients consist: J_2 =8\\cdot 10-5and C22 =0.33\\cdot 10-5. We have no data about non-sphericity of inner core of Mercury. Planned missions to Mercury (BepiColombo and Messenger) promise to

  8. Enrichment of cadmium in biomasses

    Energy Technology Data Exchange (ETDEWEB)

    Gwenner, C.; Wittig, H.; Glombitza, F.

    1986-01-01

    The uptake of cadmium ions from an aqueous solution by living, resting, and dead biomasses was investigated. The dependence of the uptaked amounts on pH-value of the medium, temperature and concentration of cadmium ions is demonstrated as well as the rate of uptake. Maximum realisable concentrations were 12 mg/g biomass in living cells and about 20 mg/g biomass in resting or dead cells, respectively.

  9. Chromium isotope uptake in carbonates

    DEFF Research Database (Denmark)

    Rodler, Alexandra

    composition of contemporaneous seawater. Marine carbonates are ubiquitous throughout Earth’s rock record rendering them a particularly interesting archive for constraining past changes in ocean chemistry. This thesis includes an investigation of the fractionation behavior of Cr isotopesduring coprecipitation......Chromium (Cr) is a redox sensitive element potentially capable of tracing fine-scale fluctuations of the oxygenation of Earth’s early surface environments and seawater. The Cr isotope composition of carbonates could perhaps be used as paleo-redox proxy to elucidate changes in the geological past...... related to the rise of oxygen and the evolution of the biosphere. However, before the Cr isotopesystem can be applied to faithfully delineate paleo-environmental changes, careful assessment of the signal robustness and a thorough understanding of the Cr cycle in Earth system processes is necessary...

  10. Chromium (VI) adsorption on boehmite

    Energy Technology Data Exchange (ETDEWEB)

    Granados-Correa, F. [Instituto Nacional de Investigaciones Nucleares, Apartado Postal 18-1027 Col., Escandon, Delegacion Miguel Hidalgo, C.P. 11801 Mexico, D.F. (Mexico)], E-mail: fgc@nuclear.inin.mx; Jimenez-Becerril, J. [Instituto Nacional de Investigaciones Nucleares, Apartado Postal 18-1027 Col., Escandon, Delegacion Miguel Hidalgo, C.P. 11801 Mexico, D.F. (Mexico)

    2009-03-15

    Boehmite was synthesized and characterized in order to study the adsorption behavior and the removal of Cr(VI) ions from aqueous solutions as a function of contact time, initial pH solution, amount of adsorbent and initial metal ion concentration, using batch technique. Adsorption data of Cr(VI) on the boehmite were analyzed according to Freundlich, Langmuir and Dubinin-Radushkevich (D-R) adsorption models. Thermodynamic parameters for the adsorption system were determinated at 293, 303, 313 and 323 K temperatures. The kinetic values and thermodynamic parameters from the adsorption process show that the Cr(VI) ions adsorption on boehmite is an endothermic and spontaneous process. These results show that the boehmite could be considered as a potential adsorbent for chromium ions in aqueous solutions.

  11. Effect of selenite and selenate on plant uptake of cadmium by maize (zea mays)

    Energy Technology Data Exchange (ETDEWEB)

    Shanker, K.; Mishra, S.; Srivastava, S. [Dayalbagh Educational Institute (India)

    1996-03-01

    Selenium has been reported to confer tolerance to toxicity of heavy metals including cadmium, a highly toxic and non essential heavy metal, which enters the food chain via plant uptake from soils. Selenium reduces availability of cadmium to plants along with other aspects of its toxicokinetics. When plants are supplied with selenite, selenium concentrations in the xylem exudate are lower than selenate. Most of the selenate was transported as selenate and unidentified organic Se compounds. In contrast, Se distribution among various Se fractions within plants does not depend significantly on whether selenite or selenate was used. Selenium has a strong tendency to form complexes with heavy metals like Cd, Hg, Ag and Tl. It has been suggested that the protective effects of selenium are due to the formation of non toxic Se-metal complexes, although the mechanism by which this protective effect is exerted remains unclear. Studies on the effect of selenium (selenite) and cadmium additions to the soil on their concentrations in lettuce and wheat has indicated the role of selenite in reduction of cadmium uptake. The cletoxifying effect of sodium selenite on cadmium ion in the freshwater fish Potyacuthus cupanus has been reported. The discovery that an element like selenium counteracts the toxicity, chemical carcinogenesis and reduces the plant uptake of other toxic metals, highlights the possibility of existence of a Se-metal interaction mechanism in soil plant systems. The uptake and translocation of root-absorbed chromium supplied through irrigation in the trivalent and hexavalant states in various parts of the onion plant (Allium cepa) grown in soil and sand culture has been recently reported by us. In continuation of that, this preliminary report describes the effect of selenite and selenate pretreatment on the uptake of cadmium in the maize plant (Zea mays).

  12. Mechanical properties of metal-ceramic systems from nickel-chromium and cobalt-chromium alloys

    Directory of Open Access Journals (Sweden)

    Mirković Nemanja

    2007-01-01

    Full Text Available Background/Aim. Metal-ceramic bond strength and alloys' elastic modulus clearly determine the potential of alloy application, because the ceramic integrity during mastication depends on these two characteristics. The aim of this study was to evaluate metal-ceramic bond strength and elastic modulus of cobalt-chromium alloys in making porcelainfused- to-metal restorations, regarding the application of the most frequent nickel-chromium alloy. Methods. The research was performed as an experimental study. Six metalceramic samples were made from nickel-chromium alloy (Wiron 99 and cobalt-chromium alloy (Wirobond C, according to the manufactures manuals and instructions from ISO 9693: 1996. Three-point bending test was performed up to the ceramic fracture. The fracture load was measured on an universal testing machine (Zwick, type 1464, with cross-head speed of 0,05mm/min. Results. The results of this study confirmed the significant differences between the metal-ceramic bond strength (p < 0.01 and elastic modulus (p < 0.001 of nickel-chromium and cobalt-chromium alloys, where cobalt-chromium alloys showed higher values for both tested parameters. Conclusion. Cobalt-chromium metal-ceramic alloys can successfully replace nickel-chromium alloys, especially for fabrication of long-span metal-ceramic bridges due to the great flexural strength.

  13. Aerosol Beam Focused-Laser Induced Plasma Spectrometer (ABF-LIPS) Continuous Emissions Multi-Metals Analyzer. Cost and Performance Report: WP-0213

    Science.gov (United States)

    2010-02-01

    munitions deactivation test incinerator. Each source was spiked with an aerosol of three to five test metals (cadmium, chromium, lead, mercury , nickel) at...beryllium, cadmium, chromium, cobalt, lead, manganese, mercury , nickel, selenium, silver, and thallium. These metals are commonly associated with...Aviation Depot (NADEP) in San Diego: a chrome plating bath, an electrode-free nickel plating bath, and a smelter /melting pot used to melt the metal

  14. Electrochemical monitoring of phytochelatin accumulation in Nicotiana tabacum cells exposed to sub-cytotoxic and cytotoxic levels of cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Fojta, Miroslav [Laboratory of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno (Czech Republic)]. E-mail: fojta@ibp.cz; Fojtova, Miloslava [Laboratory of Molecular Epigenetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno (Czech Republic); Havran, Ludek [Laboratory of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno (Czech Republic); Pivonkova, Hana [Laboratory of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno (Czech Republic); Dorcak, Vlastimil [Laboratory of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno (Czech Republic); Sestakova, Ivana [J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, 182 23 Prague 8 (Czech Republic)

    2006-02-03

    Cadmium belongs to the most dangerous environmental pollutants among the toxic heavy metals seriously affecting vital functions in both animal and plant cells. It has been previously shown that cadmium ions at 50-100 {mu}M concentrations caused tobacco BY-2 (TBY-2) cells to enter apoptosis within several days of exposure. Phytochelatins (PCs), the 'plant metallothioneins', are cysteine-rich peptides involved in detoxification of heavy metals in plants. The PCs are synthesized in response to the heavy metal exposure. In this paper, we utilized electrochemical analysis to monitor accumulation of PCs in the TBY-2 cells exposed to cadmium ions. Measurements of a characteristic PC signal at mercury electrode in the presence of cobalt ions made it possible to detect changes in the cellular PC levels during the time of cultivation, starting from 30 min after exposure. Upon TBY-2 cultivation in the presence of cytotoxic cadmium concentrations, the PC levels remarkably increased during the pre-apoptotic phase and reached a limiting value at cultivation times coinciding with apoptosis trigger. The PC level observed for a sub-cytotoxic cadmium concentration (10 {mu}M) was about three-times lower than that observed for the 50 or 100 {mu}M cadmium ions after 5 days of exposure. We show that using a simple electrochemical analysis, synthesis of PCs in plant cells can be easily followed in parallel with other tests of the cellular response to the toxic heavy metal stress.

  15. AEROSOL BEHAVIOR IN CHROMIUM WASTE INCINERATION

    Institute of Scientific and Technical Information of China (English)

    Suyuan Yu

    2003-01-01

    Cr2O3 is considered as the dominant incineration product during the combustion disposal of chromium waste. A hydrogen/air diffusion flame was employed to simulate the industrial process of incineration. Cr2O3 aerosols were generated inside the flame by the gas phase reaction of chromium and oxygen. Chromium came from the rapid decomposition of chromium hexacarbonyl (Cr(CO)6) at room temperature and was carried into the combustion chamber by hydrogen. Aerosol and clusters can then be easily formed in the flame by nucleation and coagulation. A two dimensional Discrete-Sectional Model (DSM) was adopted to calculate the Cr2O3 aerosol behavior. The experimental measurement method was Dynamic Light Scattering. The numerically predicted results agreed well with those of the experimental measurement. Both results show that the Cr2O3 aerosol size reached about 70 nanometers at the flame top.

  16. Localized Corrosion of Chromium Coated Steel

    NARCIS (Netherlands)

    Zhang, X.; Beentjes, P.; Mol, A.; Terryn, H.

    2006-01-01

    In this paper, we report on the studies of the local corrosion behaviour of chromium-coated ultra low carbon steel in NaCl solution using polarization, electrochemical impedance spectroscopy (EIS) and SVET.

  17. CHROMIUM CONCENTRATION IN TEHRAN ELECTROPLATING PLANTS

    Directory of Open Access Journals (Sweden)

    M. Ghiasseddin

    1988-12-01

    Full Text Available Hazards of soluable hexa and trivalent chromium have been documented by many investigators. But there was no information regarding safety of about 5000 workers at exposure risk to chromium in 600 primitive electroplating work shops of Tehran. During this study more than 70% of work shops were inactive due to some of their own problems. Out of active plants those that were relatively more cooperative 43 manual and 3 semi automatic were investigated for chromium concentration both by personal and environmental Sampling. The Samples were analyzed by AAS and cholormetry. In 30% of personal and 40% of environmental samples both total and Cr+6 were higher than ACGIH’S TLV. In one of semiautomatic plant Cr=6 was as high as 0.71 mg/m.3.Regarding injuries, following observations were made: Nasal wound 85%, skin irritation 73% , Dermatitis 35% and some other chromium related injuries including 2 cases of Septum perforations.

  18. Potentiometry: A Chromium (III) -- EDTA Complex

    Science.gov (United States)

    Hoppe, J. I.; Howell, P. J.

    1975-01-01

    Describes an experiment that involves the preparation of a chromium (III)-EDTA compound, a study of its infrared spectrum, and the potentiometric determination of two successive acid dissociation constants. (Author/GS)

  19. 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

  20. Standard Specification for Low-Carbon Nickel-Chromium-Molybdenum, Low-Carbon Nickel-Chromium-Molybdenum-Copper, Low-Carbon Nickel-Chromium-Molybdenum-Tantalum, Low-Carbon Nickel-Chromium-Molybdenum-Tungsten, and Low-Carbon Nickel-Molybdenum-Chromium Alloy Plate, Sheet, and Strip

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2015-01-01

    Standard Specification for Low-Carbon Nickel-Chromium-Molybdenum, Low-Carbon Nickel-Chromium-Molybdenum-Copper, Low-Carbon Nickel-Chromium-Molybdenum-Tantalum, Low-Carbon Nickel-Chromium-Molybdenum-Tungsten, and Low-Carbon Nickel-Molybdenum-Chromium Alloy Plate, Sheet, and Strip

  1. Standard Specification for Low-Carbon Nickel-Chromium-Molybdenum, Low-Carbon Nickel-Molybdenum-Chromium, Low-Carbon Nickel-Molybdenum-Chromium-Tantalum, Low-Carbon Nickel-Chromium-Molybdenum-Copper, and Low-Carbon Nickel-Chromium-Molybdenum-Tungsten Alloy Rod

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2015-01-01

    Standard Specification for Low-Carbon Nickel-Chromium-Molybdenum, Low-Carbon Nickel-Molybdenum-Chromium, Low-Carbon Nickel-Molybdenum-Chromium-Tantalum, Low-Carbon Nickel-Chromium-Molybdenum-Copper, and Low-Carbon Nickel-Chromium-Molybdenum-Tungsten Alloy Rod

  2. 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.

  3. 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.

  4. Permeation of chromium salts through human skin in vitro

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Fullerton, A; Avnstorp, C

    1992-01-01

    Chromium permeation studies were performed on full thickness human skin in diffusion cells. All samples were analysed for the total chromium content by graphite furnace Zeeman-corrected atomic absorption spectrometry. Some samples were analysed by an ion chromatographic method permitting...... the simultaneous determination of Cr(VI) and Cr(III) as well. The amounts of chromium found in all skin layers were significantly higher when potassium dichromate was applied to the skin compared with chromium chloride or chromium nitrate. Chromium could only be detected in the recipient phase after application...... of the dichromate solution. Chromium skin levels increased with increasing concentrations of applied chromium salts up to 0.034 M Cr. The amount of chromium in recipient phase and skin layers increased with increasing pH when the applied solution contained potassium dichromate. This was ascribed to a decreased skin...

  5. Zinc-induced protection against cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Early, J.L.; Schnell, R.C.

    1978-02-01

    Pretreatment of male rats with cadmium acetate potentiates the duration of hexobarbital hypnosis and inhibits the rate of hepatic microsomal drug metabolism. Pretreatment of rats with zinc acetate protects against these alterations in drug action elicited by cadmium.

  6. Mercury content of edible mushrooms

    Energy Technology Data Exchange (ETDEWEB)

    Woidich, H.; Pfannhauser, W.

    1975-05-01

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

  7. [Metallic mercury poisoning. Case report].

    Science.gov (United States)

    Fichte, B; Ritzau, F; Assmann, H

    1984-02-01

    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.

  8. Direct access to macroporous chromium nitride and chromium titanium nitride with inverse opal structure.

    Science.gov (United States)

    Zhao, Weitian; DiSalvo, Francis J

    2015-03-21

    We report a facile synthesis of single-phase, nanocrystalline macroporous chromium nitride and chromium titanium nitride with an inverse opal morphology. The material is characterized using XRD, SEM, HR-TEM/STEM, TGA and XPS. Interconversion of macroporous CrN to Cr2O3 and back to CrN while retaining the inverse opal morphology is also demonstrated.

  9. Metallothionein and bioaccumulation of cadmium in juvenile bluegills exposed to aqueous and sediment-associated cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Cope, W.G.

    1991-01-01

    The author evaluated metallothionein (MT), free (unbound) hepatic cadmium and whole body cadmium as indicators of cadmium exposure in juvenile bluegills Lepomis macrochirus in laboratory tests. Two types of cadmium exposure were tested; aqueous and sediment-associated. In the aqueous tests, fish were exposed to cadmium (0.0 to 32.3 [mu]g/L) in an intermittent-flow diluter. In the sediment-associated cadmium test, fish were exposed to resuspended river sidment containing 1.3 to 21.4 [mu]g Cd/g (dry weight) at a nominal total suspended solids concentration of 1,000 mg/L in revolving, circular glass exposure chambers. Total cadmium concentrations were measured in various bluegill liver fractions, whole bluegill, water, and resuspended sediment to assess the partitioning and bioaccumulation of cadmium after the tests. Mean concentrations of MT and free cadmium in bluegill livers and concentrations of cadmium in whole bluegills were positively correlated with aqueous cadmium concentration and were equally suitable as indicators of aqueous cadmium exposure. Sediment-associated cadmium was biologically available, but to a lesser extent than aqueous cadmium. Cadmium concentrations in whole bluegills exposed to resuspended river sediment were 1.5- to 3.5-fold the concentrations in bluegills in sediment-free controls. Free cadmium and MT concentrations in bluegill liver and whole-body cadmium concentrations in bluegills were positively correlated with the cadmium concentrations in filtered water, resuspended sediment, and bulk river sediment; however, whole-body cadmim concentrations were a more sensitive indicator of exposure to sediment-associated cadmium than either free cadmium or MT concentratons in liver.

  10. The Key Technique of Manufacture of Dense Chromium Sesquioxide Refractories

    Institute of Scientific and Technical Information of China (English)

    LIMaoqiang; ZHANGShuying; 等

    1998-01-01

    Dense chromium sesquioxide refractories have widely been used in the kilns for making alkai-free and anti-alkali glass fibers due to their excellent re-sistance to molten glasses.Densifications of chromium sesquioxide during sintering can be blocked by evaporation of chromium trioxide derived from oxidation at high temperature,In this paper the mech-anism of sintering chromium oxide and the process-ing technique for making dense chromium sesquiox-ide refractories are discussed .A process in laboratory scale for making dense chromium sesquioxide bricks is demonstrated.

  11. Bioavailability of cadmium from linseed and cocoa

    DEFF Research Database (Denmark)

    Hansen, Max; Sloth, Jens Jørgen; Rasmussen, Rie Romme

    In Denmark and EU the exposure of cadmium from food is at a level that is relatively close to the Tolerable Daily Intake (TDI). This report describes an investigation of the bioavailability of cadmium in selected food items known to contain high levels of cadmium. The purpose was to provide data ...... or crushed linseed nor the intake of cocoa and chocolate....

  12. Mercury poisoning: a diagnostic challenge.

    Science.gov (United States)

    Tezer, Hasan; Kaya, Aysenur; Kalkan, Gokhan; Erkocoglu, Mustafa; Ozturk, Kubra; Buyuktasli, Muge

    2012-11-01

    Clinical features of mercury poisoning are nonspecific, and a detailed history is very valuable. The silvery, shiny appearance of mercury makes it very exciting and attractive for children. The overall half-life of elemental mercury in the body averages approximately 2 months. Chelation therapy with dimercaptosuccinic acid is the treatment of choice if the urine or blood level of mercury is high or the symptoms are profound. Here, we describe a 14-year-old boy with fever, respiratory distress, and body rash. Investigation leading to a diagnosis of mercury poisoning was made only after his mother presented with the similar symptoms a few days later.

  13. The Sun, Mercury, and Venus

    CERN Document Server

    Elkins-Tanton, Linda T

    2010-01-01

    The Messenger mission to Mercury opened a new window into the inner solar system. In 2008, this mission began a number of years of flybys, culminating in an orbital insertion around Mercury and producing unparalleled observations about this mysterious innermost planet. Mercury orbits so close to the Sun, from the point of view of Earth, that seeing it from the Earth against the Sun's glare is a great challenge. At the same time, the huge gravitational force of the Sun makes it a challenge to put a mission on Mercury without losing it into the Sun. Now, with heightened understanding of Mercury,

  14. Synthesis of a new complex Chromium (Ⅲ) 2-mercaptonicotinate

    Institute of Scientific and Technical Information of China (English)

    LI Wei; HAO Er-jun; JIANG Yu-qin

    2004-01-01

    Chromium is an essential trace element for mammals[1-3].Diabetes is a chronic disease with major health consequence. Studies show that the occurrence of diabetes have great thing to do with the chromium deficient. Almost 40 years after the first report of glucose tolerance factor(GTF)[4]no conclusive evidence for an isolable ,biologically active form of chromium exited. Three materials have been proposed to be the biologically active form of chromium: "glucose tolerance factor", chromium Picolinate and low-molecular-weight chromium-binding substance (LWMCr)[5]So there is potential for the design of new chromium drugs[6].Chromium compounds have been used in medicine for centuries and there is potential for the design of new chromium drugs.2-Mercaptonicotinic acid(MN) displays the interesting biological activity. Chromium( Ⅲ )2-mercaptonicotinate is a common and effective biologically active form of Chromium. The test of biological activity indicated that may be useful in treating of diabetes. In this paper, we reported the The synthesis route is as follow:The structure of the complex has been characterized by IR, elemental analysis, MS,atomic absorption spectroscopy, X-ray powder diffraction and TG-DTA analysis.They indicate that the structure of Chromium 2-mercaptonicotinate.HPLC is used for determination of the purity. Studies show that the complex has a good biological activity for supplement tiny dietary chromium,lowering blood glucose levels, lowering serum lipid levels and increasing lean body mass.

  15. 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

  16. Plane Mercury librations

    Science.gov (United States)

    Barkin, Yu. V.; Ferrandiz, J. M.

    2009-04-01

    Introduction. In 1988 I. Kholin [1] has developed a precision method of determination of parameters of rotation of planets on complex radar-tracking observations on two radio telescopes making base and definitely carried on surface of the Earth. His American colleagues for the period approximately in 4 with small year have executed a series of radar-tracking measurements on a method and I. Kholin's program [2] and have obtained for the specified period 21 values of angular velocity of rotation of this planet [3]. With the help of numerical integration of the equations of rotary motion on the found values they managed to determine with high accuracy the basic dynamic parameter in the theory of Mercury librations (B - A)•Cm = (2.03± 0.12) × 10-4 and the corresponding to it the value of amplitude of the basic librations35"8 ± 2"1. These results have served as convincing arguments for the benefit of the Peale's assumption, that a core of Mercury is liquid, or in partially molten [4]. Authors also managed to obtain for the first time parameters of resonant librations in a longitude which opening from radar observations was predicted earlier [5]. Its amplitude makes about 300", the period is equal approximately to 12 years. In the paper [6] parameters of the perturbed rotational motion have been determined with the help of the analytical theory and with formal using of results of mentioned work [3] on determination of 21 values of angular velocity of Mercury. In result the estimations of amplitudes of forced librations of first five harmonics with the periods: 87.97 d, 43.99 d, 29.33 d, 21.99 d and 17.59 d have been obtained. The appropriate amplitudes make values:34"05 ± 1"27, 3"59 ± 0"13, 0"354 ± 0"013, 0"072 ± 0"003 and 0"016 ± 0"001. The amplitude and the period of free librations of Mercury in a longitude are determined: 290"9 ± 67"0 and 12.37 ± 0.23 yr, consequently. The phase of this variation has made28401 ± 1402. In the paper we construct the similar

  17. Oral cadmium chloride intoxication in mice

    DEFF Research Database (Denmark)

    Andersen, O; Nielsen, J B; Svendsen, P

    1988-01-01

    Diethyldithiocarbamate (DDC) is known to alleviate acute toxicity due to injection of cadmium salts. However, when cadmium chloride was administered by the oral route, DDC enhanced rather than alleviated the acute toxicity; both oral and intraperitoneal (i.p.) administration of DDC had this effect....... Thus, orally administered DDC enhanced cadmium-induced duodenal and ileal tissue damage and inhibition of peristalsis, as indicated by an increased intestinal transit time. At low cadmium doses, the whole-body retention of cadmium was increased by oral DDC administration. Intraperitoneally administered...

  18. Serum chromium levels in gestational diabetes mellitus

    Directory of Open Access Journals (Sweden)

    P G Sundararaman

    2012-01-01

    Full Text Available Objective: To measure serum chromium level in women with gestational diabetes mellitus (GDM from Chennai, South India. Materials and Methods: Thirty women with gestational diabetes, 60 age matched controls. Inclusion criteria: Gestational age 22-28 weeks, age group 20-35 years. Exclusion Criteria: Gestational age beyond 28 weeks, malnutrition or presence of infection. Serum chromium was measured using inductive couple plasma emission spectrometer. Results: Serum chromium levels of women with GDM, 1.59+/-0.02 ng/ml (range: 0.16-4.0 ng/ml were lower than in controls (4.58+/-0.62 ng/ml; range 0.82-5.33 ng/ml (P < 0.001. However, there were no significant differences among cases and controls when subdivided by parity. Conclusions: Women with GDM from a South Indian city had lower levels of serum chromium compared to pregnant women without GDM. Studies may be done whether chromium supplementation is useful in this group of women.

  19. Surface Chemistry and Spectroscopy of Chromium in Inorganic Oxides

    NARCIS (Netherlands)

    Weckhuysen, B.M.; Wachs, I.E.; Schoonheydt, R.A.

    1996-01-01

    Focuses on the surface chemistry and spectroscopy of chromium in inorganic oxides. Characterization of the molecular structures of chromium; Mechanics of hydrogenation-dehydrogenation reactions; Mobility and reactivity on oxidic surfaces.

  20. Arsenic-cadmium interaction in rats.

    Science.gov (United States)

    Díaz-Barriga, F; Llamas, E; Mejía, J J; Carrizales, L; Santoyo, M E; Vega-Vega, L; Yáñez, L

    1990-11-01

    Simultaneous exposure to cadmium and arsenic is highly probable in the urban area of San Luis Potosi, Mexico due to common localization of copper and zinc smelters. Therefore, in this work, rats were intraperitoneally exposed either to cadmium or arsenic alone, or simultaneously to both metals. The effects of these treatments on three different toxicological parameters were studied. Cadmium modified the LD50 of arsenic and conversely arsenic modified the LD50 for cadmium. At the histopathological level, arsenic appeared to protect against the cadmium effects, especially on testes. This protective effect seemed to be related to the glutathione levels found in this tissue: rats exposed to both arsenic and cadmium, presented glutathione values intermediate to those observed after exposure to either metal alone; arsenic had the highest value and cadmium the lowest. In liver, rats exposed to arsenic, cadmium or arsenic and cadmium, presented glutathione values below those in the saline group, with the lowest value corresponding to the arsenic and cadmium treatment. The results appear to support the proposed interaction between arsenic and cadmium and coexposure to both metals seems to alter certain effects produced by either metal alone.

  1. Insulin Expression in Rats Exposed to Cadmium

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objectives To investigate the effects of cadmium exposure on insulin expression in rats. Methods Eighteen adult SD assessed. The levels of cadmium and zinc in pancreas, blood and urine glucose, serum insulin and urine NAG (N-acyetyl-β-glucosaminidase) were determined. The gene expressions of metallothionein (MT) and insulin were also measured,and the oral glucose tolerance tests (OGTT) were carried out. Results The contents of cadmium in pancreas in cadmium-treated rats were higher than that in the control group, which was associated with slight increase of zinc in pancreas.not change significantly after cadmium administration, and the UNAG had no change in Cd-treated group. The gene expression the change of the expression of insulin, MT-Ⅰ and MT-Ⅱ genes. Cadmium can influence the biosynthesis of insulin, but does not induce the release of insulin. The dysfunction of pancreas occurs earlier than that of kidney after administration of cadmium.

  2. Residual Chromium in Leather by Instrumental Neutron Activation Analysis

    OpenAIRE

    S. Okoh; I. O. Okunade; D. J. Adeyemo; Ahmed, Y A; A. A. Audu; E. Amali

    2012-01-01

    Problem statement: Most tanning processes employ the use of chromium sulphate. For chromium tanned leather, finished products may contain high amount of residual chromium. This may pose some health hazards, since chromium is known to be toxic at elevated concentration. This justifies the need for the study. Approach: Various samples of leather were collected from a tannery, a leather crafts market, a leather dump site and from local tanners all in Kano, Nigeria in 2009. The samples were irrad...

  3. Hazards of Mercury.

    Science.gov (United States)

    Environmental Research, 1971

    1971-01-01

    Common concern for the protection and improvement of the environment and the enhancement of human health and welfare underscore the purpose of this special report on the hazards of mercury directed to the Secretary's Pesticide Advisory Committee, Department of Health, Education, and Welfare. The report summarizes the findings of a ten-member study…

  4. Mercury's core evolution

    Science.gov (United States)

    Deproost, Marie-Hélène; Rivoldini, Attilio; Van Hoolst, Tim

    2016-10-01

    Remote sensing data of Mercury's surface by MESSENGER indicate that Mercury formed under reducing conditions. As a consequence, silicon is likely the main light element in the core together with a possible small fraction of sulfur. Compared to sulfur, which does almost not partition into solid iron at Mercury's core conditions and strongly decreases the melting temperature, silicon partitions almost equally well between solid and liquid iron and is not very effective at reducing the melting temperature of iron. Silicon as the major light element constituent instead of sulfur therefore implies a significantly higher core liquidus temperature and a decrease in the vigor of compositional convection generated by the release of light elements upon inner core formation.Due to the immiscibility in liquid Fe-Si-S at low pressure (below 15 GPa), the core might also not be homogeneous and consist of an inner S-poor Fe-Si core below a thinner Si-poor Fe-S layer. Here, we study the consequences of a silicon-rich core and the effect of the blanketing Fe-S layer on the thermal evolution of Mercury's core and on the generation of a magnetic field.

  5. MERCURY CEMS: TECHNOLOGY UPDATE

    Science.gov (United States)

    The paper reviews the technologies involved with continuous emission monitors (CEMs) for mercury (Hg) which are receiving incresed attention and focus. Their potential use as a compliance assurance tool is of particular interest. While Hg CEMs are currently used in Europe for com...

  6. MERCURY CYCLING AND BIOMAGNIFICATION

    Science.gov (United States)

    Mercury cycling and biomagnification was studied in man-made ponds designed for watering livestock on the Cheyenne River Sioux Reservation in South Dakota. Multiple Hg species were quantified through multiple seasons for 2 years in total atmospheric deposition samples, surface wa...

  7. 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

  8. Hexavalent and trivalent chromium in leather: What should be done?

    Science.gov (United States)

    Moretto, Angelo

    2015-11-01

    Trivalent chromium compounds are used for leather tanning, and chromium may be released during use of leather goods. In certain instances, small amounts of hexavalent chromium can be formed and released. Both trivalent and hexavalent chromium can elicit allergic skin reaction in chromium sensitised subjects, the latter being significantly more potent. Induction of sensitisation only occurs after exposure to hexavalent chromium. A minority of subjects are sensitised to chromium, and in a fraction of these subjects allergic skin reaction have been described after wearing leather shoes or, less frequently, other leather goods. The evidence that in all these cases the reaction is related to hexavalent chromium is not always strong. The content of hexavalent chromium in leather is regulated in European Union, but rate of release rather than content is relevant for allergic skin reaction. The role of trivalent chromium appear much less relevant if at all. Modern tanning procedure do not pose significant risk due to either hexavalent or trivalent chromium. Dismissing bad quality and worn-off leather goods is relevant in reducing or eliminating the skin reaction. It should also be pointed out that shoe components or substances other than chromium in leather may cause allergic/irritative skin reactions.

  9. 21 CFR 73.1015 - Chromium-cobalt-aluminum oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Chromium-cobalt-aluminum oxide. 73.1015 Section 73... LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1015 Chromium-cobalt-aluminum oxide. (a) Identity. The color additive chromium-cobalt-aluminum oxide is a blue-green pigment obtained by calcining...

  10. 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, ...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-07-25

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

  12. Standard Specification for Nickel-Chromium-Molybdenum-Columbium Alloy (UNS N06625), Nickel-Chromium-Molybdenum-Silicon Alloy (UNS N06219), and Nickel-Chromium-Molybdenum-Tungsten Alloy (UNS N06650) Rod and Bar

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2014-01-01

    Standard Specification for Nickel-Chromium-Molybdenum-Columbium Alloy (UNS N06625), Nickel-Chromium-Molybdenum-Silicon Alloy (UNS N06219), and Nickel-Chromium-Molybdenum-Tungsten Alloy (UNS N06650) Rod and Bar

  13. Small Mercury Relativity Orbiter

    Science.gov (United States)

    Bender, Peter L.; Vincent, Mark A.

    1989-01-01

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

  14. 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.

  15. 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

  16. Studying chromium biosorption using arabica coffee leaves

    Directory of Open Access Journals (Sweden)

    Luis Carlos Florez García

    2010-05-01

    Full Text Available This work was aimed at providing an alternative for removing heavy metals such as chromium from waste water (effluent from the leather industry and galvanoplasty (coating with a thin layer of metal by electrochemical means, using coffee leaves as bio- mass. Using arabica coffee (Castle variety leaves led to 82% chromium removal efficiency for 1,000 mg/L synthetic dissolutions in 4 pH dissolution operating conditions, 0 rpm agitation, 0.149 mm diameter biomass particle size and 0.85 g/ml biomass / dissolution volume ratio.

  17. New mixed aluminium–chromium diarsenate

    Directory of Open Access Journals (Sweden)

    Mohamad Alem Bouhassine

    2017-03-01

    Full Text Available Potassium chromium aluminium diarsenate, KCr1/4Al3/4As2O7, was prepared by solid-state reaction. The structure consists of (Cr1/4/Al3/4O6 octahedra and As2O7 diarsenate groups sharing corners to build up a three-dimensional anionic framework. The potassium cations are located in wide channels running along the c-axis direction. The crystal structure is isostructural with the triclinic AIMIIIX2O7 (AI = alkali metal; MIII = Al, Cr, Fe; X = As, P compounds. However, the MIII octahedrally coordinated site is 25% partially occupied by chromium and 75% by aluminium.

  18. Strategies for chromium bioremediation of tannery effluent.

    Science.gov (United States)

    Garg, Satyendra Kumar; Tripathi, Manikant; Srinath, Thiruneelakantan

    2012-01-01

    Bioremediation offers the possibility of using living organisms (bacteria, fungi, algae,or plants), but primarily microorganisms, to degrade or remove environmental contaminants, and transform them into nontoxic or less-toxic forms. The major advantages of bioremediation over conventional physicochemical and biological treatment methods include low cost, good efficiency, minimization of chemicals, reduced quantity of secondary sludge, regeneration of cell biomass, and the possibility of recover-ing pollutant metals. Leather industries, which extensively employ chromium compounds in the tanning process, discharge spent-chromium-laden effluent into nearby water bodies. Worldwide, chromium is known to be one of the most common inorganic contaminants of groundwater at pollutant hazardous sites. Hexavalent chromium poses a health risk to all forms of life. Bioremediation of chromium extant in tannery waste involves different strategies that include biosorption, bioaccumulation,bioreduction, and immobilization of biomaterial(s). Biosorption is a nondirected physiochemical interaction that occurs between metal species and the cellular components of biological species. It is metabolism-dependent when living biomass is employed, and metabolism-independent in dead cell biomass. Dead cell biomass is much more effective than living cell biomass at biosorping heavy metals, including chromium. Bioaccumulation is a metabolically active process in living organisms that works through adsorption, intracellular accumulation, and bioprecipitation mechanisms. In bioreduction processes, microorganisms alter the oxidation/reduction state of toxic metals through direct or indirect biological and chemical process(es).Bioreduction of Cr6+ to Cr3+ not only decreases the chromium toxicity to living organisms, but also helps precipitate chromium at a neutral pH for further physical removal,thus offering promise as a bioremediation strategy. However, biosorption, bioaccumulation, and

  19. 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.

  20. MERCURY DEPOSITION AND LAKE QUALITY TRENDS

    Science.gov (United States)

    Watershed factors influence the differing trends in mercury residue levels. Fish mercury concentrations show positive correlations with water color, methylmercury concentrations, and plankton mercury, and negative correlations with pH and alkalinity.

  1. 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 ... situations, criminal prosecution. back to top Dangers of Mercury Exposure to mercury can have serious health consequences. ...

  2. Modulation of cadmium bioaccumulation and enhancing cadmium tolerance in Pichia kudriavzevii by sodium chloride preincubation.

    Science.gov (United States)

    Ma, Ning; Li, Chunsheng; Zhang, Dandan; Yu, Jinzhi; Xu, Ying

    2016-07-01

    Application of growing microorganisms for cadmium removal is limited by the sensitivity of living cells to cadmium. The effects of sodium chloride (NaCl) preincubation on the cadmium bioaccumulation and tolerance of Pichia kudriavzevii and Saccharomyces cerevisiae were investigated in this study. NaCl preincubation significantly reduced the intracellular and cell-surface cadmium bioaccumulation of P. kudriavzevii at both 6 and 20 mg L(-1) cadmium, while no obvious effect was observed in S. cerevisiae except that the intracellular cadmium bioaccumulation at 20 mg L(-1) cadmium was reduced obviously by 20-60 g L(-1)  NaCl. For both yeasts, the improved contents of protein and proline after NaCl preincubation contributed to the cadmium tolerance. The thiol contents in P. kudriavzevii under cadmium stress were alleviated by NaCl preincubation, which might be due to the decrease of intracellular cadmium bioaccumulation. NaCl preincubation enhanced the contents of glycerol and trehalose in P. kudriavzevii under cadmium stress, while no acceleration was observed in S. cerevisiae. The results suggested that NaCl preincubation could be applied in cadmium removal by growing P. kudriavzevii to increase the cadmium tolerance of the yeast.

  3. Chromium allergy and dermatitis: prevalence and main findings

    DEFF Research Database (Denmark)

    Bregnbak, David; Johansen, Jeanne D.; Jellesen, Morten Stendahl;

    2015-01-01

    The history of chromium as an allergen goes back more than a century, and includesan interventional success with national legislation that led to significant changes inthe epidemiology of chromium allergy in construction workers. The 2015 EU Leather Regulation once again put a focus on chromium...... allergy, emphasizing that the investigation of chromium allergy is still far from complete. Our review article on chromium focuses on the allergen’s chemical properties, its potential exposure sources, and the allergen’s interaction with the skin, and also provides an overview of the regulations...

  4. Pharmacokinetic Modeling of Trivalent and Hexavalent Chromium Based on Ingestion and Inhalation of Soluble Chromium Compounds.

    Science.gov (United States)

    1991-12-01

    be largely Cr(III) although some Cr(VI) exposure probably also occurs. Stainless-steel welders are exposed to nickel as well as to chromium compounds...welders are equivocal with respect to involvement of chromium, particularly since nickel in some chemical forms is an established lung carcinogen (Stern...microglobulin (Lindberg and Vesterberg, 1983), retinol-binding protein (Franchini and Mutti , 1988), B-glucuronidase ( Mutti et al., 1979), and kidney brush border

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

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Jose A.; Rodrigues, Carlos M.; Almeida, Paulo J.; Valente, Ines M.; Goncalves, Luis M. [Requimte - Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, no. 687, 4169-007 Porto (Portugal); Compton, Richard G. [Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ (United Kingdom); Barros, Aquiles A., E-mail: ajbarros@fc.up.pt [Requimte - Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, no. 687, 4169-007 Porto (Portugal)

    2011-09-09

    Highlights: {yields} At very cathodic accumulation potentials (overpotential deposition) the voltammetric signals of Zn{sup 2+}, Cd{sup 2+}, Pb{sup 2+} and Cu{sup 2+} increase. {yields} 5 to 10-fold signal increase is obtained. {yields} This effect is likely due to mercury drop oscillation at such cathodic potentials. {yields} This effect is also likely due to added local convection at the mercury drop surface caused by the evolution of hydrogen bubbles. - Abstract: An improved approach to the anodic stripping voltammetric (ASV) determination of heavy metals, using the hanging mercury drop electrode (HMDE), is reported. It was discovered that using very cathodic accumulation potentials, at which the solvent reduction occurs (overpotential deposition), the voltammetric signals of zinc(II), cadmium(II), lead(II) and copper(II) increase. When compared with the classical methodology a 5 to 10-fold signal increase is obtained. This effect is likely due to both mercury drop oscillation at such cathodic potentials and added local convection at the mercury drop surface caused by the evolution of hydrogen bubbles.

  6. Bioaccumulation of cadmium by growing Zygosaccharomyces rouxii and Saccharomyces cerevisiae.

    Science.gov (United States)

    Li, Chunsheng; Jiang, Wei; Ma, Ning; Zhu, Yinglian; Dong, Xiaoyan; Wang, Dongfeng; Meng, Xianghong; Xu, Ying

    2014-03-01

    Bioaccumulation via growing cells is a potential technique for heavy metal removal from food materials. The cadmium bioaccumulation characteristics by growing Zygosaccharomyces rouxii and Saccharomyces cerevisiae were investigated. Z. rouxii displayed powerful cadmium removal ability at low cadmium concentrations, which mainly depended on the intracellular cadmium bioaccumulation. The percentage of intracellular cadmium bioaccumulation of both yeasts obviously decreased with the increase of initial biomass and cadmium concentrations. Low pH and elevated concentrations of zinc and copper significantly decreased the intracellular cadmium bioaccumulation of both yeasts but improved the cadmium tolerance and the cell-surface cadmium bioaccumulation of Z. rouxii. Cadmium removal of Z. rouxii was improved by zinc and copper conditionally. Z. rouxii that possessed more powerful cadmium tolerance and removal ability at low pH and high concentration of competing ions can be developed into a potential cadmium removal agent using in complex food environment in future.

  7. Biological groundwater treatment for chromium removal at low hexavalent chromium concentrations.

    Science.gov (United States)

    Mamais, Daniel; Noutsopoulos, Constantinos; Kavallari, Ioanna; Nyktari, Eleni; Kaldis, Apostolos; Panousi, Eleni; Nikitopoulos, George; Antoniou, Kornilia; Nasioka, Maria

    2016-06-01

    The objective of this work is to develop and evaluate biological groundwater treatment systems that will achieve hexavalent chromium reduction and total chromium removal from groundwater at hexavalent chromium (Cr(VI)) groundwater concentrations in the 0-200 μg/L range. Three lab-scale units operated, as sequencing batch reactors (SBR) under aerobic, anaerobic and anaerobic-aerobic conditions. All systems received groundwater with a Cr(VI) content of 200 μg/L. In order to support biological growth, groundwater was supplemented with milk, liquid cheese whey or a mixture of sugar and milk to achieve a COD concentration of 200 mg/L. The results demonstrate that a fully anaerobic system or an anaerobic-aerobic system dosed with simple or complex external organic carbon sources can lead to practically complete Cr(VI) reduction to Cr(III). The temperature dependency of maximum Cr(VI) removal rates can be described by the Arrhenius relationship. Total chromium removal in the biological treatment systems was not complete because a significant portion of Cr(III) remained in solution. An integrated system comprising of an anaerobic SBR followed by a sand filter achieved more than 95% total chromium removal thus resulting in average effluent total and dissolved chromium concentrations of 7 μg/L and 3 μg/L, respectively.

  8. Removal of cadmium (II), lead (II) and chromium (VI) in water with nanomaterials

    OpenAIRE

    Contreras Rodríguez, Ada Rebeca

    2015-01-01

    Resumen Un gran desafío para este siglo es el saneamiento de los residuos generados durante las actividades industriales, domésticas y agrícolas. El agua, como parte vital del ciclo de vida, está fuertemente afectada por estas actividades y finalmente se puede volver inutilizable. Entre los numerosos contaminantes que se encuentran en el agua, los metales pesados requieren atención especial ya que no son biodegradables y con frecuencia se acumulan en el medio ambiente causando efectos negativ...

  9. Genotypic and environmental variation in cadmium, chromium, arsenic, nickel, and lead concentrations in rice grains

    Institute of Scientific and Technical Information of China (English)

    CHENG Wang-da; ZHANG Guo-ping; YAO Hai-gen; WU Wei; XU Min

    2006-01-01

    Genotypic and environmental variation in Cd, Cr, As, Ni and Pb concentrations of grains, and the relationships between these heavy metals and Fe, Zn were investigated using 9 rice genotypes grown in 6 locations for two successive years.Significant genotypic variation was detected in the five heavy metal concentrations in grains, indicating the possibility to reduce the concentration of these heavy metals in grains through breeding approach. The environmental effect varied with metal, with Pb and Ni having greater variation than the other three metals. There was significant genotype-environment (location) interaction of the concentrations of all five heavy metals in grains, suggesting the importance of cultivar choice in producing rice with low heavy metal concentrations in grains for a given location. Correlation analysis showed that Cd and As, Cr and Ni, and As and Pb concentrations in rice grains were closely associated, and that Ni concentration in grains was negatively correlated with Zn concentration.

  10. Temporal changes in rat liver gene expression after acute cadmium and chromium exposure.

    Directory of Open Access Journals (Sweden)

    Michael S Madejczyk

    Full Text Available U.S. Service Members and civilians are at risk of exposure to a variety of environmental health hazards throughout their normal duty activities and in industrial occupations. Metals are widely used in large quantities in a number of industrial processes and are a common environmental toxicant, which increases the possibility of being exposed at toxic levels. While metal toxicity has been widely studied, the exact mechanisms of toxicity remain unclear. In order to further elucidate these mechanisms and identify candidate biomarkers, rats were exposed via a single intraperitoneal injection to three concentrations of CdCl2 and Na(2Cr(2O(7, with livers harvested at 1, 3, or 7 days after exposure. Cd and Cr accumulated in the liver at 1 day post exposure. Cd levels remained elevated over the length of the experiment, while Cr levels declined. Metal exposures induced ROS, including hydroxyl radical (•OH, resulting in DNA strand breaks and lipid peroxidation. Interestingly, ROS and cellular damage appeared to increase with time post-exposure in both metals, despite declines in Cr levels. Differentially expressed genes were identified via microarray analysis. Both metals perturbed gene expression in pathways related to oxidative stress, metabolism, DNA damage, cell cycle, and inflammatory response. This work provides insight into the temporal effects and mechanistic pathways involved in acute metal intoxication, leading to the identification of candidate biomarkers.

  11. Temporal Changes in Rat Liver Gene Expression after Acute Cadmium and Chromium Exposure

    Science.gov (United States)

    Madejczyk, Michael S.; Baer, Christine E.; Dennis, William E.; Minarchick, Valerie C.; Leonard, Stephen S.; Jackson, David A.; Stallings, Jonathan D.; Lewis, John A.

    2015-01-01

    U.S. Service Members and civilians are at risk of exposure to a variety of environmental health hazards throughout their normal duty activities and in industrial occupations. Metals are widely used in large quantities in a number of industrial processes and are a common environmental toxicant, which increases the possibility of being exposed at toxic levels. While metal toxicity has been widely studied, the exact mechanisms of toxicity remain unclear. In order to further elucidate these mechanisms and identify candidate biomarkers, rats were exposed via a single intraperitoneal injection to three concentrations of CdCl2 and Na2Cr2O7, with livers harvested at 1, 3, or 7 days after exposure. Cd and Cr accumulated in the liver at 1 day post exposure. Cd levels remained elevated over the length of the experiment, while Cr levels declined. Metal exposures induced ROS, including hydroxyl radical (•OH), resulting in DNA strand breaks and lipid peroxidation. Interestingly, ROS and cellular damage appeared to increase with time post-exposure in both metals, despite declines in Cr levels. Differentially expressed genes were identified via microarray analysis. Both metals perturbed gene expression in pathways related to oxidative stress, metabolism, DNA damage, cell cycle, and inflammatory response. This work provides insight into the temporal effects and mechanistic pathways involved in acute metal intoxication, leading to the identification of candidate biomarkers. PMID:25993096

  12. Fleet Readiness Center - Southeast Technology Development Program (Cadmium & Hexavalent Chromium Reduction)

    Science.gov (United States)

    2014-11-01

    Priming – Ty I Aircraft Priming – Ty II Component Priming Aluminum CC Magnesium CC Anodize Seal Anodize Strip Chemical Deoxidizing Phosphate ...None N Painting Polysulfide Sealant MIL-PRF-87133, Ty III PR-1436 LPS 680 Grade B (No Products) Y Surface Finishing Aluminum Chromate Conversion ...Coating MIL-DTL-81706 Alodine 600 LPS 320 TCP Y Surface Finishing Magnesium Chromate Conversion Coating AMS-M-3171, Ty III Sodium Dichromate - Technical

  13. Determination of cadmium, zinc, copper chromium and arsenic in crude oils

    NARCIS (Netherlands)

    Stigter, J.B.; Haan, H.P.M. de; Guicherit, R.

    1998-01-01

    One of the sources of trace heavy metal elements in air are emissions by the oil industry, either directly through stack emissions from refineries or indirectly from emissions of combustion of hydrocarbons. Emission estimates are based mainly on the trace metal content of the crude oil processed. Fr

  14. Cadmium, zinc, copper, silver and chromium(III) removal from wastewaters by Sphaerotilus natans

    Energy Technology Data Exchange (ETDEWEB)

    Lodi, A.; Solisio, C.; Converti, A.; Del Borghi, M. [Istituto di Ingegneria Chimica e di Processo ``G.B. Bonino``, Genova (Italy)

    1998-09-01

    Living cells of Sphaerotilus natans are used for heavy metal`s (Cd, Zn, Cu Ag, and Cr) removal from aqueous solutions simulating the polluting power of acid industrial wastewaters. At low metal concentrations (<25 mg/l) this microorganism is able to remove within 8-15 days Cd, Zn, Cu, and Ag with excellent yields (from 81 to 99%) often increasing with starting metal concentration. The yield observed for Cr(III) removal, never exceeding 60%, is not appreciably influenced by the starting biomass level; in addition, the time necessary to reach the equilibrium concentration is always remarkably longer (>30 days) than for the other metals. At much higher concentrations, the removal of all the metals is strongly affected in terms of both yield reduction and increase in the time necessary to reach the equilibrium concentrations. Under the hypothesis of mass transfer limitation, the kinetic study of batch runs suggests that metal diffusion from the bulk to the surface of S. natans clumps could be responsible not only for the simple biosorption of the tested metallic micronutrients or abiotic metals, but even for the cell penetration by ions of biological significance, like Mg{sup 2+} and Fe{sup 3+}. (orig.)

  15. Temporal Changes in Rat Liver Gene Expression after Acute Cadmium and Chromium Exposure

    Science.gov (United States)

    2015-05-19

    to ROS production [22]. The International Agency for Research on Cancer (IARC) has classified both Cd and Cr as known human carcinogens [23]. Although...metabolism. There were thirteen pathways that were common to both exposures. The majority of the identified inflam - mation pathways were found after Cd...by macrophages and neutrophils. ROS can interact with DNA, leading to ad- duct formation that impairs base-pairing and/or blocks DNA replication and

  16. Prosopis laevigata a potential chromium (VI) and cadmium (II) hyperaccumulator desert plant.

    Science.gov (United States)

    Buendía-González, L; Orozco-Villafuerte, J; Cruz-Sosa, F; Barrera-Díaz, C E; Vernon-Carter, E J

    2010-08-01

    The bioaccumulation of Cr(VI) and Cd(II) in Prosopis laevigata and the effect of these heavy metals on plant growth were assessed. P. laevigata seeds were cultured during 50 days on modified Murashige-Skoog medium supplemented with four different concentrations of Cr(VI) (0-3.4mM) and Cd(II) (0-2.2mM), respectively. Heavy metals did not stop germination, but smaller plants with fewer leaves and secondary roots were produced. Seedlings showed an accumulation of 8176 and 21,437 mg Cd kg(-1) and of 5461 and 8090 mg Cr kg(-1) dry weight, in shoot and root, when cultured with 0.65 mM Cd(II) and 3.4mM Cr(VI), respectively. These results indicated that significant translocation from the roots unto aerial parts took place. A bioaccumulation factor greater than 100 for Cd and 24 for Cr was exhibited by the seedlings. P. laevigata can be considered as a potential hyperaccumulator of Cd(II) and Cr(VI) species and considered as a promising candidate for phytoremediation purposes.

  17. The electronic structure of antiferromagnetic chromium

    DEFF Research Database (Denmark)

    Skriver, Hans Lomholt

    1981-01-01

    The author has used the local spin density formalism to perform self-consistent calculations of the electronic structure of chromium in the non-magnetic and commensurate antiferromagnetic phases, as a function of the lattice parameter. A change of a few per cent in the atomic radius brings...

  18. A Kinetic Model of Chromium in a Flame

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Chromium has been identified as a carcinogenic metal.Incineration is the useful method for disposal of toxic chromium hazard waste and a chromium kinetic model in a flame is very important to study chromium oxidation.Chromium chemical kinetics over a range of temperatures of a hydrogen/air flame is proposed.Nine chromium compounds and fifty-eight reversible chemical reactions were considered The forward reaction rates are calculated based on the molecular collision approach for unknown ones and Arrhenius's Law for known ones.The backward reaction rates were calculated according to forward reaction rates, the equilibrium constants and chemical thermodynamics.It is verified by several equilibrium cases and is tested by a hydrogen/air diffusion flame.The results show that the kinetic model could be used in cases in which the chromium kinetics play an important role in a flame

  19. Cadmium content of plants as affected by soil cadmium concentration

    Energy Technology Data Exchange (ETDEWEB)

    Lehoczky, E. [Pannon Univ. of Agricultural Sciences, Keszthely (Hungary); Szabados, I.; Marth, P. [Plant Health and Soil Conservation Station, Higany (Hungary)

    1996-12-31

    Pot experiments were conducted in greenhouse conditions to study the effects of increasing cadmium (Cd) levels on biomass production and Cd contents in corn, (Zea mays L.), garlic (Allium sativum L.), and spinach (Spinacia oleracea L.). Plants were grown in two soil types: Eutric cambisol soil and A gleyic luvisol soil. Spinach proved to be the most sensitive to Cd treatments as its biomass considerably decreased with the increasing Cd levels. Cadmium contents of the three crops increased with increasing levels of Cd applications. Statistical differences were observed in the Cd contents of crops depending on soil type. With the same Cd rates, Cd tissue concentration of test plants grown in the strongly acidic Gleyic luvisol soil were many times higher than that of plants grown in a neutral Eutric cambisol soil. 14 refs., 4 tabs.

  20. 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.

  1. Method for scavenging mercury

    Science.gov (United States)

    Chang, Shih-ger; Liu, Shou-heng; Liu, Zhao-rong; Yan, Naiqiang

    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.

  2. Mercury removal sorbents

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. Tolerance to cadmium and cadmium-binding ligands in Great Salt Lake brine shrimp (Artemia salina)

    Energy Technology Data Exchange (ETDEWEB)

    Jayasekara, S.; Drown, D.B.; Sharma, R.P.

    1986-02-01

    Information on the accumulation of cadmium in cytosolic proteins of Great Lake brine shrimp (Artemia salina) was obtained from animals collected directly from the lake and also from animal hatched and maintained in three sublethal concentrations of cadmium (0.5, 2.0, 5.0 ppm) in saltwater aquaria. Brine shrimp growth under these conditions was monitored by measuring body lengths during a 7-day exposure period. Heat-stable, cadmium-binding ligands were isolated and identified by Sephadex G-75 chromatography and atomic absorption spectrophotometry. Cadmium was found to be equally distributed between high and low molecular weight proteins in animals collected from the lake and the 0.5 ppm cadmium group. There was also a slight growth stimulation noted in the 0.5-pm group. Higher cadmium incorporation was noted in low molecular weight fractions with increasing cadmium concentration in the exposure media. Low molecular weight fractions were also found to have high uv absorption characteristics at 250 nm and low absorption at 280 nm. Molecular weight of the cadmium-binding ligands was found to be 11,000 as estimated by the gel filtration method. De novo synthesis of this protein was increased as a function of cadmium concentration in the media. However, slow accumulation of cadmium in other protein fractions was also noticed in higher cadmium exposure groups, suggesting the existence of possible tolerance mechanisms in brine shrimp exposed to suspected acute cadmium concentrations.

  4. Zone refining of cadmium and related characterization

    Indian Academy of Sciences (India)

    N R Munirathnam; D S Prasad; Ch Sudheer; J V Rao; T L Prakash

    2005-06-01

    We present the zone refining results of cadmium using horizontal resistive zone refiner under constant flow of moisture free hydrogen gas. The boron impurity in cadmium can be avoided using quartz (GE 214 grade) boat in lieu of high pure graphite boat. The analytical results using inductively coupled plasma optical emission spectrometry (ICPOES) show that majority of the impurities are less than the detection limits. Comparatively, zinc is the most difficult impurity element to remove in cadmium matrix by zone refining.

  5. The Epigenetic Effects of Prenatal Cadmium Exposure.

    Science.gov (United States)

    Vilahur, Nadia; Vahter, Marie; Broberg, Karin

    2015-06-01

    Prenatal exposure to the highly toxic and common pollutant cadmium has been associated with adverse effects on child health and development. However, the underlying biological mechanisms of cadmium toxicity remain partially unsolved. Epigenetic disruption due to early cadmium exposure has gained attention as a plausible mode of action, since epigenetic signatures respond to environmental stimuli and the fetus undergoes drastic epigenomic rearrangements during embryogenesis. In the current review, we provide a critical examination of the literature addressing prenatal cadmium exposure and epigenetic effects in human, animal, and in vitro studies. We conducted a PubMed search and obtained eight recent studies addressing this topic, focusing almost exclusively on DNA methylation. These studies provide evidence that cadmium alters epigenetic signatures in the DNA of the placenta and of the newborns, and some studies indicated marked sexual differences for cadmium-related DNA methylation changes. Associations between early cadmium exposure and DNA methylation might reflect interference with de novo DNA methyltransferases. More studies, especially those including environmentally relevant doses, are needed to confirm the toxicoepigenomic effects of prenatal cadmium exposure and how that relates to the observed health effects of cadmium in childhood and later life.

  6. 77 FR 6627 - National Emission Standards for Hazardous Air Pollutant Emissions: Hard and Decorative Chromium...

    Science.gov (United States)

    2012-02-08

    ... aluminum to provide resistance to corrosion. The chromium anodizing process is used to coat aircraft parts... Hazardous Air Pollutant Emissions: Hard and Decorative Chromium Electroplating and Chromium Anodizing Tanks... Pollutant Emissions: Hard and Decorative Chromium Electroplating and Chromium Anodizing Tanks; and...

  7. 49 CFR 173.164 - Mercury (metallic and articles containing mercury).

    Science.gov (United States)

    2010-10-01

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

  8. CHROMIUM INDUCED CYTOTOXICITY IN BLACKGRAM (VIGNA MUNGO L.

    Directory of Open Access Journals (Sweden)

    A. Chidambaram ، P. Sundaramoorthy ، A. Murugan ، K. Sankar Ganesh ، L. Baskaran

    2009-01-01

    Full Text Available Chromium is known to be highly toxic to biological systems. This study was designed to determine the mutagenic effects of different concentrations (0, 10, 25, 50, 100 and 200 mg/L of hexavalent chromium on root tip cells of blackgram (Vigna mungo L. Hepper. The blackgram seeds were equi-spacially arranged in sterilized petriplates lined with filter paper and they were treated with different concentrations of chromium solution. In germination studies, the morphological growth parameters such as germination percentage, root length, shoot length fresh weight and dry weight of blackgram seedlings were decreased with increasing dose of chromium concentrations. No germination of blackgram seeds was recorded at 300mg/l chromium concentration. Chromosome aberration assay was used to determine the mitotic indices and rate of chromosome aberration in blackgram root tip cells due to chromium treatment. The results showed that the mitotic indices were complicated due to different concentrations of chromium. However, the increase in chromium concentration has led to a gradual increase in the percentage of chromosomal aberration and mitotic index. The chromosome length, absolute chromosome length and average chromosome lengths were gradually found to decrease. There was no considerable change in 2n number of chromosome with the increase in chromium concentrations. It is concluded that the hexavalent chromium has significant mutagenic effect on the root tip cells of blackgram.

  9. 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.

  10. 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.

  11. Mercury as a health hazard.

    Science.gov (United States)

    Curtis, H A; Ferguson, S D; Kell, R L; Samuel, A H

    1987-03-01

    Pink disease has virtually disappeared since teething powders were withdrawn. We describe a case in a boy who was exposed to metallic mercury vapour. We discuss the potential health hazard of spilled elemental mercury in the house and the difficulties of removing it from the environment.

  12. Mercury concentration in bivalve molluscs

    Directory of Open Access Journals (Sweden)

    Szkoda Józef

    2015-09-01

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

  13. Mercury: Beethoven Quadrangle, H-7

    Science.gov (United States)

    2000-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-07-25

    Mercury (Hg) in the Savannah River Site Liquid Waste System (LWS) originated from decades of canyon processing where it was used as a catalyst for dissolving the aluminum cladding of reactor fuel. Approximately 60 metric tons of mercury is currently present throughout the LWS. Mercury has long been a consideration in the LWS, from both hazard and processing perspectives. In February 2015, a Mercury Program Team was established at the request of the Department of Energy to develop a comprehensive action plan for long term management and removal of mercury. Evaluation was focused in two Phases. Phase I activities assessed the Liquid Waste inventory and chemical processing behavior using a system by system review methodology and determined the speciation of the different mercury forms (Hg+, Hg++, elemental Hg, organomercury, and soluble versus insoluble mercury) within the LWS. The evaluation of the mercury behavior in the salt processing flowsheet indicates: • 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. • 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 forms in the assembled salt batches in Tanks 21/49 pass through the Actinide Removal Process (ARP) / Modular Caustic Side Solvent Extraction Unit (MCU) process to Tank 50 with no significant change in the mercury chemistry. • In Tank 50, Decontaminated Salt Solution (DSS) from ARP/MCU is the major contributor to the total mercury including MHg. More information can be found about what

  15. 21 CFR 872.3700 - Dental mercury.

    Science.gov (United States)

    2010-04-01

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

  16. Improvement of cadmium phytoremediation after soil inoculation with a cadmium-resistant Micrococcus sp.

    Science.gov (United States)

    Sangthong, Chirawee; Setkit, Kunchaya; Prapagdee, Benjaphorn

    2016-01-01

    Cadmium-resistant Micrococcus sp. TISTR2221, a plant growth-promoting bacterium, has stimulatory effects on the root lengths of Zea mays L. seedlings under toxic cadmium conditions compared to uninoculated seedlings. The performance of Micrococcus sp. TISTR2221 on promoting growth and cadmium accumulation in Z. mays L. was investigated in a pot experiment. The results indicated that Micrococcus sp. TISTR2221significantly promoted the root length, shoot length, and dry biomass of Z. mays L. transplanted in both uncontaminated and cadmium-contaminated soils. Micrococcus sp. TISTR2221 significantly increased cadmium accumulation in the roots and shoots of Z. mays L. compared to uninoculated plants. At the beginning of the planting period, cadmium accumulated mainly in the shoots. With a prolonged duration of cultivation, cadmium content increased in the roots. As expected, little cadmium was found in maize grains. Soil cadmium was significantly reduced with time, and the highest percentage of cadmium removal was found in the bacterial-inoculated Z. mays L. after transplantation for 6 weeks. We conclude that Micrococcus sp. TISTR2221 is a potent bioaugmenting agent, facilitating cadmium phytoextraction in Z. mays L.

  17. Femtosecond laser surface structuring and oxidation of chromium thin coatings: Black chromium

    Energy Technology Data Exchange (ETDEWEB)

    Kotsedi, L., E-mail: Kotsedi@tlabs.ac.za [UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, College of Graduate Studies, University of South Africa, Muckleneuk Ridge, P.O. Box 392, Pretoria (South Africa); Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West 7129, P.O. Box 722, Somerset West, Western Cape (South Africa); Nuru, Z.Y. [UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, College of Graduate Studies, University of South Africa, Muckleneuk Ridge, P.O. Box 392, Pretoria (South Africa); Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West 7129, P.O. Box 722, Somerset West, Western Cape (South Africa); Mthunzi, P. [National Laser Centre, Council for Scientific and Industrial Research, 0001 Pretoria (South Africa); Muller, T.F.G. [University of the Western Cape, Physics Department, Bellville, 7535 Cape Town (South Africa); Eaton, S.M. [Physics Department, Politecnico di Milano, Piazza Leonardo Da Vinci, 32, 20133 Milano (Italy); Julies, B. [University of the Western Cape, Physics Department, Bellville, 7535 Cape Town (South Africa); Manikandan, E. [UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, College of Graduate Studies, University of South Africa, Muckleneuk Ridge, P.O. Box 392, Pretoria (South Africa); Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West 7129, P.O. Box 722, Somerset West, Western Cape (South Africa); Ramponi, R. [Physics Department, Politecnico di Milano, Piazza Leonardo Da Vinci, 32, 20133 Milano (Italy); Maaza, M. [UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, College of Graduate Studies, University of South Africa, Muckleneuk Ridge, P.O. Box 392, Pretoria (South Africa); Nanosciences African Network (NANOAFNET), iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West 7129, P.O. Box 722, Somerset West, Western Cape (South Africa)

    2014-12-01

    Highlights: • Oxidation of the chromium thin film to chromium oxide by femtosecond laser with a fundamental wavelength of 1064 nm. • Solar absorber from chromium oxide that low percentage reflectance. • Femtosecond laser oxidation, with a de-focused laser. • Chromium oxide formation by femtosecond laser in normal ambient. - Abstract: In view of their potential applications as selective solar absorbers, chromium coatings on float glass substrates were nano/micro structured by femtosecond laser in air. Raman and X-rays diffraction investigations confirmed the formation of an ultra-porous α-Cr{sub 2}O{sub 3} layer at the surface; higher is the input laser power, enhanced is the crystallinity of the α-Cr{sub 2}O{sub 3} layer. The α-Cr{sub 2}O{sub 3} layer with the Cr underneath it in addition to the photo-induced porosity acted as a classical ceramic–metal nano-composite making the reflectance to decrease significantly within the spectral range of 190–1100 nm. The average reflectance decreased from 70 to 2%.

  18. Production of basic chromium sulfate by using recovered chromium from ashes of thermally treated leather.

    Science.gov (United States)

    Dettmer, Aline; Nunes, Keila Guerra Pacheco; Gutterres, Mariliz; Marcílio, Nilson Romeu

    2010-04-15

    Leather wastes tanned with chromium are generated during the production process of leather, hence the wastes from hand crafted goods and footwear industries are a serious environmental problem. The thermal treatment of leather wastes can be one of the treatment options because the wastes are rich in chromium and can be used as a raw material for sodium chromate production and further to obtain several chromium compounds. The objective of this study was to utilize the chromium from leather wastes via basic chromium sulfate production to be subsequently applied in a hide tanning. The obtained results have shown that this is the first successful attempt to achieve desired base properties of the product. The result was achieved when the following conditions were applied: a molar ratio between sodium sulfite and sodium dichromate equal to 6; reaction time equal to 5 min before addition of sulfuric acid; pH of sodium dichromate solution equal to 2. Summarizing, there is an opportunity to utilize the dangerous wastes and reused them in the production scheme by minimizing or annulling the environmental impact and to attend a sustainable process development concept.

  19. Mercury accumulation and loss in mallard eggs

    Science.gov (United States)

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

    2004-01-01

    Female mallards (Anas platyrhynchos) were fed diets containing 5, 10, or 20 ppm mercury as methylmercury chloride. One egg was collected from each bird before the start of the mercury diets and 15 eggs were collected from each bird while it was being fed mercury. The mercury diets were then replaced by uncontaminated diets, and each female was allowed to lay 29 more eggs. Mercury levels in eggs rose to about 7,18, and 35 ppm wet-weight in females fed 5,10, or 20 ppm mercury, respectively. Mercury levels fell to about 0.16,0.80, and 1.7 ppm in the last egg laid by birds that had earlier been fed 5, 10, or 20 ppm mercury, respectively. Higher concentrations of mercury were found in egg albumen than in yolk, and between 95 and 100% of the mercury in the eggs was in the form of methylmercury.

  20. Interactions of chromium with microorganisms and plants.

    Science.gov (United States)

    Cervantes, C; Campos-García, J; Devars, S; Gutiérrez-Corona, F; Loza-Tavera, H; Torres-Guzmán, J C; Moreno-Sánchez, R

    2001-05-01

    Chromium is a highly toxic non-essential metal for microorganisms and plants. Due to its widespread industrial use, chromium (Cr) has become a serious pollutant in diverse environmental settings. The hexavalent form of the metal, Cr(VI), is considered a more toxic species than the relatively innocuous and less mobile Cr(III) form. The presence of Cr in the environment has selected microbial and plant variants able to tolerate high levels of Cr compounds. The diverse Cr-resistance mechanisms displayed by microorganisms, and probably by plants, include biosorption, diminished accumulation, precipitation, reduction of Cr(VI) to Cr(III), and chromate efflux. Some of these systems have been proposed as potential biotechnological tools for the bioremediation of Cr pollution. In this review we summarize the interactions of bacteria, algae, fungi and plants with Cr and its compounds.

  1. Nuclear metamorphosis in mercury

    Science.gov (United States)

    Cardone, F.; Albertini, G.; Bassani, D.; Cherubini, G.; Guerriero, E.; Mignani, R.; Monti, M.; Petrucci, A.; Ridolfi, F.; Rosada, A.; Rosetto, F.; Sala, V.; Santoro, E.; Spera, G.

    2016-12-01

    The conditions of local Lorentz invariance (LLI) breakdown, obtained during neutron emission from a sonicated cylindrical bar of AISI 304 steel, were reproduced in a system made of a mole of mercury. After 3 min, a part of the liquid transformed into solid state material, in which isotopes were found with both higher and lower atomic mass with respect to the starting material. Changes in the atomic weight without production of gamma radiation and radionuclides are made possible by deformed space-time reactions.

  2. 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.

  3. Effect of polyethylene glycol on electrochemically deposited trivalent chromium layers

    Institute of Scientific and Technical Information of China (English)

    Joo-Yul LEE; Man KIM; Sik-Chol KWON

    2009-01-01

    The structural characteristics of the trivalent chromium deposits and their interfacial behavior in the plating solution with and without polyethylene glycol molecules were observed by using various electrochemical methods such as cyclic voltammetry, open circuit potential transition, electrochemical impedance spectroscopy, scanning electron microscopy and X-ray photoelectron spectrometry. It is shown that the polyethylene glycol molecules make the reductive current density lower in the trivalent chromium plating system and promote a hydrogen evolution reaction through their adsorption on the electrode surface. And the trivalent chromium layer formed from the polyethylene glycol-containing solution has somewhat higher density of cracks on its surface and results in a lower film resistance, lower polarization resistance, and higher capacitance in a corrosive atmosphere. It is also revealed that the formation of chromium carbide layer is facilitated in the presence of polyethylene glycol, which means easier electrochemical codeposition of chromium and carbon, not single chromium deposition.

  4. Speciation and recovery of chromium from chromite ore processing residues.

    Science.gov (United States)

    Sreeram, K J; Ramasami, T

    2001-10-01

    The processing of chromite ore is associated with the generation of large quantities of solid wastes containing chromium, which have been disposed of as landfill for many years. The mobilization and operational speciation of chromium contained in soils contaminated with metal salts are important in terms of the environment. Several methods have been employed for the extraction and recovery of solid wastes. Chromium contained in contaminated soils and solid wastes can be categorized as exchangeable, oxidizable, carbonate-bound, reducible and residual. The results from this study indicate a need for efficient leaching methodologies in chromite ore processing plants to decrease the non-detrital fractions of chromium in the residue. Aggressive methodologies are required to recover chromium from the detrital fractions. The potential benefits of employing sodium peroxide for the complete recovery of chromium from chromite residue have been demonstrated, and the need to ensure the safety of the process has been emphasized.

  5. Chromium Toxicity: Reductive Enzymes in Humans.

    Science.gov (United States)

    2007-11-02

    internal organs (e.g. lungs, liver, kidneys) [24,27,64], pulmonary fibrosis and chronic bronchitis [2], skin ulcers and allergic dermatitis [2], and...cross the skin [2] and are readily transported across cell membranes [18] via an anion carrier [6]. Cr compounds are also mutagenic [67], and the bulk of...reduced nicotinamide adenine dinucleotide phosphate-cytochrome P450 oxidoreductase- dependent chromium(VI) reduction. Analyst 120:935-938. 42. Miura, A

  6. Electrodialytic Removal of Cadmium from Straw Ash

    DEFF Research Database (Denmark)

    Hansen, Henrik; Ottosen, Lisbeth M.; Villumsen, Arne;

    1999-01-01

    A problem with flyash from straw and wood combustion is the high level of heavy metals, especially cadmium. Two electrodialytic remediation experiments were carried out on cadmium polluted flyash from straw combustion. The flyash could be cleaned to 1/3 of its initial level after 24 days...

  7. Cadmium and children : Exposure and health effects

    NARCIS (Netherlands)

    Schoeters, G.; Hond, E. Den; Zuurbier, M.; Naginiene, R.; Hazel, P.J. van den; Stilianakis, N.; Ronchetti, R.; Koppe, J.G.

    2006-01-01

    Cadmium exposure and accumulation in the body start at young age. Exposure routes in children are mainly via food, environmental tobacco smoke and house dust. Excretion from the body is limited. Cadmium accumulation in the kidney is responsible for effects such as nephrotoxicity and osteoporosis whi

  8. Cadmium and children: exposure and health effects.

    Science.gov (United States)

    Schoeters, Greet; Den Hond, Elly; Zuurbier, Moniek; Naginiene, Rima; van den Hazel, Peter; Stilianakis, Nikolaos; Ronchetti, Roberto; Koppe, Janna G

    2006-10-01

    Cadmium exposure and accumulation in the body start at young age. Exposure routes in children are mainly via food, environmental tobacco smoke and house dust. Excretion from the body is limited. Cadmium accumulation in the kidney is responsible for effects such as nephrotoxicity and osteoporosis which are observed at adult age. Cadmium exposure through inhalation is also associated with lung cancer in adulthood. Although transfer to the neonate through the placenta and through breast milk is limited, teratogenic and developmental effects were observed in experimental animals. The database on human studies involving children is limited, yet effects on motoric and perceptual behaviour in children have been associated with elevated in utero cadmium exposure. In school age children urinary cadmium levels were associated with immune suppressive effects. More studies are needed to confirm these results. Experimental data in vitro and in animals refer to effects of cadmium on the hypothalamus-pituitary axis at different levels. This may lead to disorders of the endocrine and/or immune system. Cadmium exposure at early age should be limited as much as possible to prevent direct effects on children and to prevent accumulation of cadmium which may have serious health effects only becoming manifest at older age.

  9. CADMIUM AND NICKEL CONTENT IN FROZEN SPINACH FROM SLOVAKIA SALES NETWORK

    Directory of Open Access Journals (Sweden)

    Radovan Stanovič

    2014-02-01

    Full Text Available In the present work, we focused on monitoring the content of hazardous elements in retail packs Spinach (Spinacia oleracea, L.. Among the most hazardous substances that can get into the spinach are nitrates, pesticide residues. The heavy metals as cadmium, mercury, cobalt, nickel, lead and copper. Into productive parts of plants may get land through the atmosphere or contaminated water. Spinach is among reigns supreme wheatgrass. It is a rich source of minerals, vitamins and folic acid. For this article we have chosen to risk elements cadmium and nickel, which we compared with the maximum level defined by the Codex Alimentarius Commission of the Slovak Republic and the values that are set out in Commission Regulation EU No. 420/2011 and no. No 1881/2006 setting maximum levels for contaminants in foods. The results obtained suggest that in either case there was no exceeded of monitored contaminants. The average levels observed risk elements were in the following intervals: Cd 0:03 to 0:10 mg.kg-1, Ni 0697-1218 mg.kg-1. The results will show that in the case of cadmium, we had exceeded the limit value in six samples and nickel was not exceeding the limit value.

  10. Dimensionally Controlled Lithiation of Chromium Oxide

    Energy Technology Data Exchange (ETDEWEB)

    Fister, Tim T. [Argonne National Lab. (ANL), Argonne, IL (United States); Hu, Xianyi [Northwestern Univ., Evanston, IL (United States); Esbenshade, Jennifer [Univ. of Illinois, Urbana-Champaign, IL (United States); Chen, Xiao [Northwestern Univ., Evanston, IL (United States); Wu, Jinsong [Northwestern Univ., Evanston, IL (United States); Dravid, Vinayak [Northwestern Univ., Evanston, IL (United States); Bedzyk, Michael [Northwestern Univ., Evanston, IL (United States); Long, Brandon [Argonne National Lab. (ANL), Argonne, IL (United States); Gewirth, Andrew A. [Univ. of Illinois, Urbana-Champaign, IL (United States); Shi, Bing [Argonne National Lab. (ANL), Argonne, IL (United States); Schlepütz, Christian M. [Argonne National Lab. (ANL), Argonne, IL (United States); Fenter, Paul [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-01-12

    Oxide conversion reactions are an alternative approach for high capacity lithium ion batteries but are known to suffer from structural irreversibility associated with the phase separation and reconstitution of reduced metal species and Li2O. In particular, the morphology of the reduced metal species is thought to play a critical role in the electrochemical properties of a conversion material. Here we use a model electrode with alternating layers of chromium and chromium oxide to better understand and control these phase changes in real-time and at molecular length scales. Despite lacking crystallinity at the atomic scale, this superstructure is observed (with X-ray reflectivity, XR) to lithiate and delithiate in a purely one-dimensional manner, preserving the layered structure. The XR data show that the metal layers act as nucleation sites for the reduction of chromium in the conversion reaction. Irreversibility during delithiation is due to the formation of a ternary phase, LiCrO2, which can be further delithiated at higher potentials. The results reveal that the combination of confining lithiation to nanoscale sheets of Li2O and the availability of reaction sites in the metal layers in the layered structure is a strategy for improving the reversibility and mass transport properties that can be used in a wide range of conversion materials.

  11. Processes affecting the remediation of chromium-contaminated sites.

    OpenAIRE

    Palmer, C.D.; Wittbrodt, P R

    1991-01-01

    The remediation of chromium-contaminated sites requires knowledge of the processes that control the migration and transformation of chromium. Advection, dispersion, and diffusion are physical processes affecting the rate at which contaminants can migrate in the subsurface. Heterogeneity is an important factor that affects the contribution of each of these mechanisms to the migration of chromium-laden waters. Redox reactions, chemical speciation, adsorption/desorption phenomena, and precipitat...

  12. New technology for comprehensive utilization of aluminum-chromium residue from chromium salts production

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-bin; QI Tian-gui; JIANG Xin-min; ZHOU Qiu-sheng; LIU Gui-hua; PENG Zhi-hong; HAN Deng-lun; ZHANG Zhong-yuan; YANG Kun-shan

    2008-01-01

    Colloidal aluminum-chromium residue(ACR) was mass-produced in chromate production process, and the large energy consumption and high recovery cost existed in traditional methods of utilizing such ACR. To overcome those problems, a new comprehensive method was proposed to deal with the ACR, and was proven valid in industry. In the new process, the chromate was separated firstly from the colloidal ACR by ripening and washing with additives, by which more than 95% hexavalent chromium was recovered. The chromium-free aluminum residue(CFAR), after properly dispersed, was digested at 120-130 ℃ and more than 90% alumina can be recovered. And then the pregnant aluminate solution obtained from digestion was seeded to precipitate aluminum hydroxide. This new method can successfully recover both alumina and sodium chromate, and thus realize the comprehensive utilization of ACR from chromate industry.

  13. Immunoassay for Cadmium Detection and Quantification

    Institute of Scientific and Technical Information of China (English)

    GONG-LIANG LIU; JU-FANG WANG; ZHI-YONG LI; SHI-ZHONG LIANG; XIAO-NING WANG

    2009-01-01

    Objective To detect cadmium in environmental and food samples by graphite furnace atomic absorption spectroscopy (GFAAS) and inductively coupled plasma atomic emission spectroscopy (ICPAES). Methods An indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) was developed based on a cadmium-specific monoclonal antibody.IC-ELISA for cadmium in environmental and food samples was evaluated. Results IC-ELISA showed an IC50 of 45.6 μg/L with a detection limit of 1.95 μg/L for cadmium,and showed a mean recovery ranging 97.67%-107.08%.The coefficient of variations for intra- and iuterassay was 3.41%-6.61% and 4.70%-9.21%,respectively.The correlation coefficient between IC-ELISA and GFAAS was 0.998. Conclusion IC-ELISA can detect and quantify cadmium residue in environmental or food samples.

  14. Cadmium a metalloestrogen: are we convinced?

    Science.gov (United States)

    Silva, Nalinda; Peiris-John, Roshini; Wickremasinghe, Rajitha; Senanayake, Hemantha; Sathiakumar, Nalini

    2012-05-01

    Metalloestrogens are inorganic metal ions that bind to and activate oestrogen receptors. They are implicated in the aetiology of oestrogen-dependent diseases such as cancers of the breast and endometrium as well as endometriosis. Cadmium is one of the most studied metalloestrogens. In this review, scientific evidence for the oestrogenic effects of cadmium is critically evaluated to determine if there is sufficient evidence to support cadmium as an aetiological factor of oestrogen-dependent disease in humans. Results of the review indicated that, although the in vitro and in vivo evidence of the oestrogenic properties of cadmium was persuasive, evidence from population-based human studies remains conflicting. Considerable knowledge gaps exist on the potential oestrogenic effect of cadmium in humans. Research that focuses on bridging these knowledge gaps would be useful in preventing and managing oestrogen-dependent disease in humans.

  15. Mercury toxicity and neurodegenerative effects.

    Science.gov (United States)

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

    2014-01-01

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

  16. 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.

  17. Cadmium mobility and accumulation in soils of the European Communities

    NARCIS (Netherlands)

    Fraters B; van Beurden AUCJ

    1993-01-01

    In this overview of the effects of cadmium pollution on agricultural soils in the European Community, both the cadmium loads on agricultural land and the soil sensitivity to cadmium accumulation have been estimated. Cadmium loads have been estimated separately for arable land and grassland. The ef

  18. Stabilization and solidification of chromium-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Cherne, C.A.; Thomson, B.M. [Univ. of New Mexico, Albuquerque, NM (United States). Civil Engineering Dept.; Conway, R. [Sandia National Labs., Albuquerque, NM (United States)

    1997-11-01

    Chromium-contaminated soil is a common environmental problem in the United States as a result of numerous industrial processes involving chromium. Hexavalent chromium [Cr(VI)] is the species of most concern because of its toxicity and mobility in groundwater. One method of diminishing the environmental impact of chromium is to reduce it to a trivalent oxidation state [Cr(III)], in which it is relatively insoluble and nontoxic. This study investigated a stabilization and solidification process to minimize the chromium concentration in the Toxicity Characteristic Leaching Procedure (TCLP) extract and to produce a solidified waste form with a compressive strength in the range of 150 to 300 pounds per square inch (psi). To minimize the chromium in the TCLP extract, the chromium had to be reduced to the trivalent oxidation state. The average used in this study was an alluvium contaminated with chromic and sulfuric acid solutions. The chromium concentration in the in the in situ soil was 1212 milligrams per kilogram (mg/kg) total chromium and 275 mg/kg Cr(VI). The effectiveness of iron, ferrous sulfate to reduce Cr(VI) was tested in batch experiments.

  19. Tribological Characteristics of Chromium-active Carbon Electroplated Composite Coatings

    Institute of Scientific and Technical Information of China (English)

    GUKa-fi; HUAMeng; Yi-min

    2004-01-01

    A process of chromium electroplating using a standard bath with additives and active carbon particles was reported, and the tribological behaviors of the composite coatings using the pin-on-disk tester and the table wear tester were i nvestig(aed. Experimental results indicate that the electroplated chromium-active carbon composite coatings exhibited the low friction coefficient anti excellent anti-wear properties whets coffered with the normal chromium electroplated ones. The formation of active carbon particles within the chromium matrices can be explained by SEM analysis and the mechanis of wear resistance of the composite coatings were studied.

  20. REINFORCEMENT OF NICKEL CHROMIUM ALLOYS WITH SAPPHIRE WHISKERS.

    Science.gov (United States)

    SAPPHIRE, COMPOSITE MATERIALS, CERAMIC FIBERS , CERAMIC FIBERS , TITANIUM COMPOUNDS, ZIRCONIUM COMPOUNDS, HYDRIDES, ADDITIVES, CHROMIUM ALLOYS, FIBER METALLURGY, IRON COMPOUNDS, ENCAPSULATION, DENSITY, SURFACE TENSION.

  1. Chromium recycling of tannery waste through microbial fermentation.

    Science.gov (United States)

    Katsifas, E A; Giannoutsou, E; Lambraki, M; Barla, M; Karagouni, A D

    2004-02-01

    An Aspergillus carbonarius isolate, selected from an established microbial culture collection, was used to study the biodegradation of chromium shavings in solid-state fermentation experiments. Approximately 97% liquefaction of the tannery waste was achieved and the liquid obtained from long-term experiments was used to recover chromium. The resulting alkaline chromium sulfate solution was useful in tanning procedures. A proteinaceous liquid was also obtained which has potential applications as a fertilizer or animal feed additive and has several other industrial uses. The A. carbonarius strain proved to be a very useful tool in tannery waste-treatment processes and chromium recovery in the tanning industries.

  2. Influence of Chelating Agents on Chromium Fate in Sediment

    Institute of Scientific and Technical Information of China (English)

    WANGXIAOCHANG; SUNJINHE; 等

    1996-01-01

    A laboratory investigation on reaction between chelating agents and chromium was conducted to evaluate the effect of chelating agents on the adsorption and desorption of chromium in sediment.The amount of adsorbed chromium(VI) in sediment decreased slightly by 5%-10% because of addition of chelating agents.Chelating agents inhibited the removal of Cr(Ⅲ)by sediment from solutions and the inhibiting effect was in the order:citric acid>tartaric acid>EDTA,Salicylic acid.No effect of chelating agents on desorption of chromium in sediment was observed.

  3. Chelation Therapy for Mercury Poisoning

    Directory of Open Access Journals (Sweden)

    Rong Guan

    2009-01-01

    Full Text Available Chelation therapy has been the major treatment for heavy metal poisoning. Various chelating agents have been developed and tested for treatment of heavy metal intoxications, including mercury poisoning. It has been clearly shown that chelating agents could rescue the toxicity caused by heavy metal intoxication, but the potential preventive role of chelating agents against heavy metal poisoning has not been explored much. Recent paper by Siddiqi and colleagues has suggested a protective role of chelating agents against mercury poisoning, which provides a promising research direction for broader application of chelation therapy in prevention and treatment of mercury poisoning.

  4. MESSENGER'S First Flyby of Mercury

    Science.gov (United States)

    Slavin, James A.

    2008-01-01

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

  5. Exploring Mercury: The Iron Planet

    OpenAIRE

    Stevenson, David J.

    2004-01-01

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

  6. Sealed nickel-cadmium battery

    Energy Technology Data Exchange (ETDEWEB)

    1989-08-15

    Overcharge protection, and especially the chargeability of a sealed Ni/Cd battery with high currents is improved by rolling a carbon-containing powdered material into the surface of the negative electrode, which material catalyzes the reduction of oxygen. Wetting of the electrode with a Tylose dispersion prior to application of the powder (by powdering, vibration or in an agitator) improves the adhesion of the powder. The cadmium electrode thus prepared combines in itself the functions of a negative principal electrode and of an auxiliary oxygen electrode.

  7. MERCURY STABILITY IN THE ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    John H. Pavlish

    1999-07-01

    The 1990 Clean Air Act Amendments (CAAAs) require the U.S. Environmental Protection Agency (EPA) to determine whether the presence of mercury and 188 other trace substances, referred to as air toxics or hazardous air pollutants (HAPs), in the stack emissions from fossil fuel-fired electric utility power plants poses an unacceptable public health risk (1). The EPA's conclusions and recommendations were presented in two reports: Mercury Study Report to Congress and Study of Hazardous Air Pollutant Emissions from Electric Utility Steam Generating Units-Final Report to Congress. The first congressional report addressed both human health and the environmental effects of anthropogenic mercury emissions, while the second report addressed the risk to public health posed by emissions of HAPs from steam electricity-generating units. The National Institute of Environmental Health Sciences is also required by the CAAAs to investigate mercury and determine a safe threshold level of exposure. Recently the National Academy of Sciences has also been commissioned by Congress to complete a report, based the available scientific evidence, regarding safe threshold levels of mercury exposure. Although the EPA reports did not state that mercury controls on coal-fired electric power stations should be required given the current state of the art, they did indicate that EPA views mercury as a potential threat to human health. It is likely that major sources of mercury emissions, including fossil-fired combustion systems, will be controlled at some point. In fact, municipal waste combustion units are already regulated. In anticipation of additional control measures, much research has been done (and continues) regarding the development of control technologies for mercury emitted from stationary sources to the atmosphere. Most approaches taken to date involve sorbent injection technologies or improve upon removal of mercury using existing technologies such as flue gas desulfurization

  8. Determination of mercury in an assortment of dietary supplements using an inexpensive combustion atomic absorption spectrometry technique.

    Science.gov (United States)

    Levine, Keith E; Levine, Michael A; Weber, Frank X; Hu, Ye; Perlmutter, Jason; Grohse, Peter M

    2005-01-01

    The concentrations of mercury in forty, commercially available dietary supplements, were determined using a new, inexpensive analysis technique. The method involves thermal decomposition, amalgamation, and detection of mercury by atomic absorption spectrometry with an analysis time of approximately six minutes per sample. The primary cost savings from this approach is that labor-intensive sample digestion is not required prior to analysis, further automating the analytical procedure. As a result, manufacturers and regulatory agencies concerned with monitoring lot-to-lot product quality may find this approach an attractive alternative to the more classical acid-decomposition, cold vapor atomic absorption methodology. Dietary supplement samples analyzed included astragalus, calcium, chromium picolinate, echinacea, ephedra, fish oil, ginger, ginkgo biloba, ginseng, goldenseal, guggul, senna, St John's wort, and yohimbe products. Quality control samples analyzed with the dietary supplements indicated a high level of method accuracy and precision. Ten replicate preparations of a standard reference material (NIST 1573a, tomato leaves) were analyzed, and the average mercury recovery was 109% (2.0% RSD). The method quantitation limit was 0.3 ng, which corresponded to 1.5 ng/g sample. The highest found mercury concentration (123 ng/g) was measured in a concentrated salmon oil sample. When taken as directed by an adult, this product would result in an approximate mercury ingestion of 7 mug per week.

  9. Postoperative systemic dissemination of injected elemental mercury.

    Science.gov (United States)

    Kang, Suk-Hyung; Park, Seung Won; Moon, Kyung-Yoon

    2011-04-01

    There were only a few reports of mercury on pulmonary artery. However, there is no data on surgery related mercury dissemination. The objective of the present article is to describe one case of postoperative injected mercury dissemination. A 19-year-old man presented severe neck pain including meningeal irritation sign and abdominal pain after injection of mercury for the purpose of suicide. Radiologic study showed injected mercury in the neck involving high cervical epidural space and subcutaneous layer of abdomen. Partial hemilaminectomy and open mercury evacuation of spinal canal was performed. For the removal of abdominal subcutaneous mercury, C-arm guided needle aspiration was done. After surgery, radiologic study showed disseminated mercury in the lung, heart, skull base and low spinal canal. Neck pain and abdominal pain were improved after surgery. During 1 month after surgery, there was no symptom of mercury intoxication except increased mercury concentration of urine, blood and hair. We assumed the bone work during surgery might have caused mercury dissemination. Therefore, we recommend minimal invasive surgical technique for removal of injected mercury. If open exposures are needed, cautious surgical technique to prohibit mercury dissemination is necessary and normal barrier should be protected to prevent the migration of mercury.

  10. Localized surface plasmon resonance mercury detection system and methods

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-03-22

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

  11. Embryotoxicity hazard assessment of cadmium and arsenic compounds using embryonic stem cells.

    Science.gov (United States)

    Stummann, T C; Hareng, L; Bremer, S

    2008-10-30

    The Embryonic Stem Cell Test (EST) has been successfully validated as an in vitro method for detecting embryotoxicity, showing a good overall test accuracy of 78% [Genschow, E., Spielmann, H., Scholz, G., Seiler, A., Brown, N., Piersma, A., Brady, M., Clemann, N., Huuskonen, H., Paillard, F., Bremer, S., Becker, K., 2002. The ECVAM international validation study on in vitro embryotoxicity tests: results of the definitive phase and evaluation of prediction models. European Centre for the Validation of Alternative Methods. Altern. Lab. Anim. 30, 151-176]. Methylmercury was the only strong in vivo embryotoxicant falsely predicted as non-embryotoxic making the metal the most significant outlayer [Genschow, E., Spielmann, H., Scholz, G., Pohl, I., Seiler, A., Clemann, N., Bremer, S., Becker, K., 2004. Validation of the Embryonic Stem Cell Test in the international ECVAM validation study on three in vitro embryotoxicity tests. Altern. Lab. Anim. 32, 209-244]. The misclassification of methylmercury and the potential environmental exposure to developmental toxic heavy metals promoted our investigation of whether the EST applicability domain covers cadmium and arsenic compounds. The EST misclassified cadmium, arsenite and arsenate compounds as non-embryotoxic, even when including arsenic metabolites (methylarsonate, methylarsonous and dimethylarsinic). The reasons were the lack of higher cytotoxicity towards embryonic stem cells as compared to more mature cells (3T3 fibroblasts) or the absence of inhibition of cardiac differentiation by specific mechanisms rather than general cytotoxicity. Including EST data on heavy metals from the literature (lithium, methylmercury, trivalent chromium and hexavalent chromium) revealed that the test correctly predicted the embryotoxic potential of three out of the seven heavy metals, indicating an insufficient predictivity for such metals. Refinement of the EST prediction model and inclusion of additional toxicological endpoints could

  12. Response of Saccharomyces cerevisiae to cadmium stress

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Luciana Mara Costa; Ribeiro, Frederico Haddad; Neves, Maria Jose [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Lab. de Radiobiologia], e-mail: luamatu@uol.com.br; Porto, Barbara Abranches Araujo; Amaral, Angela M.; Menezes, Maria Angela B.C. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Lab. de Ativacao Neutronica], e-mail: menezes@cdtn.br; Rosa, Carlos Augusto [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Microbiologia], e-mail: carlrosa@icb.ufmg

    2009-07-01

    The intensification of industrial activity has been greatly contributing with the increase of heavy metals in the environment. Among these heavy metals, cadmium becomes a serious pervasive environmental pollutant. The cadmium is a heavy metal with no biological function, very toxic and carcinogenic at low concentrations. The toxicity of cadmium and several other metals can be mainly attributed to the multiplicity of coordination complexes and clusters that they can form. Some aspects of the cellular response to cadmium were extensively investigated in the yeast Saccharomyces cerevisiae. The primary site of interaction between many toxic metals and microbial cells is the plasma membrane. Plasma-membrane permeabilisation has been reported in a variety of microorganisms following cadmium exposure, and is considered one mechanism of cadmium toxicity in the yeast. In this work, using the yeast strain S. cerevisiae W303-WT, we have investigated the relationships between Cd uptake and release of cellular metal ions (K{sup +} and Na{sup +}) using neutron activation technique. The neutron activation was an easy, rapid and suitable technique for doing these metal determinations on yeast cells; was observed the change in morphology of the strains during the process of Cd accumulation, these alterations were observed by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) during incorporation of cadmium. (author)

  13. Response of Pleurotus ostreatus to cadmium exposure

    Energy Technology Data Exchange (ETDEWEB)

    Favero, N.; Bressa, G.; Costa, P. (Univ. of Padua (Italy))

    1990-08-01

    The possibility of utilizing agroindustrial wastes in the production of edible, high-quality products (e.g., mushrooms) implies the risk of bringing toxic substances, such as heavy metals, into the human food chain. Thus, growth in the presence of cadmium and cadmium accumulation limits have been studied in the industrially cultivated fungus P. ostreatus. Fruit body production is substantially unaffected in the presence of 25, 139, and 285 mg Cd/kg of dried substrate. Cadmium concentration in fruit bodies is related to cadmium substrate level, the metal being present at higher levels in caps (22-56 mg/kg dry wt) than in stems (13-36 mg/kg dry wt). Concentration factor (CF), very low in the controls (about 2), further decreases in treated specimens. The presence of a cadmium control mechanism in this fungi species is suggested. Fruit body cadmium levels could, however, represent a risk for P. ostreatus consumers, according to FAO/WHO limits related to weekly cadmium intake.

  14. Interactions of cadmium and zinc during pregnancy

    Energy Technology Data Exchange (ETDEWEB)

    Sorell, T.L.

    1988-01-01

    The interactions of cadmium exposure and zinc during pregnancy were investigated by studying rats exposed to 0, 5, 50, or 100 ppm cadmium (as CdCl{sub 2}) in the drinking water from day 6 to day 20 of pregnancy. On day 20 of pregnancy, fetuses of rats exposed to 50 and 100 ppm of cadmium were slightly but significantly smaller than those of control animals. Fetal weight was negatively correlated with fetal cadmium concentration and positively correlated with fetal cadmium concentration. Significant fetal cadmium accumulation occurred in both the 50 and 100 ppm cadmium exposure groups; fetal zinc concentrations were decreased. Maternal liver and kidney zinc concentrations were slightly elevated, and the possible role of maternal organ sequestration of available zinc is discussed. The activity of two zinc metalloenzymes, alkaline phosphatase and {delta}-aminolevulinic acid dehydratase, was decreased in maternal and fetal tissues, providing evidence of an alteration in zinc metabolism. In addition, the placental transport of {sup 65}Zn was characterized in control animals and compared to exposed groups; placental zinc transport was significantly decreased in the 50 and 100 ppm exposure groups.

  15. Cadmium inhalation and male reproductive toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Ragan, H.A.; Mast, T.J. (Battelle Pacific Northwest Laboratories, Richland, WA (USA))

    1990-01-01

    Cadmium is a highly toxic element that is cumulative and has a long biological half-life in mammals. The severe toxicity of cadmium in man has been known for more than 100 years. Despite the knowledge that cadmium is toxic, only 20 human cases of poisoning via ingestion were recorded prior to 1941, whereas in the ensuing five-year period more than 680 cases of cadmium poisonings from accidental oral ingestion of this metal were documented. Some of the recorded effects of exposure to cadmium in laboratory animals include renal tubular damage, placental and testicular necrosis, structural and functional liver damage, osteomalacia, testicular tumors, teratogenic malformations, anemia, hypertension, pulmonary edema, chronic pulmonary emphysema, and induced deficiencies of iron, copper, and zinc. Some of these effects have also been observed in human after accidental exposures to cadmium oxide fumes and are characteristic of the syndrome described in Japan as Itai Itai disease in which ingestion of cadmium is the inciting chemical.134 references.

  16. "Cavitation in a Mercury Target"

    Energy Technology Data Exchange (ETDEWEB)

    West, C.D.

    2000-09-06

    Recent theoretical work on the formation of bubble nucleation centers by energetic particles leads to some reasonably credible calculations of the maximum negative pressure that might be sustained without bubble formation in the mercury target of the Spallation Neutron Source.

  17. Cavitation in a Mercury Target

    Energy Technology Data Exchange (ETDEWEB)

    West, C.D.

    2000-09-01

    Recent theoretical work on the formation of bubble nucleation centers by energetic particles leads to some reasonably credible calculations of the maximum negative pressure that might be sustained without bubble formation in the mercury target of the Spallation Neutron Source.

  18. Relativity and the mercury battery.

    Science.gov (United States)

    Zaleski-Ejgierd, Patryk; Pyykkö, Pekka

    2011-10-06

    Comparative, fully relativistic (FR), scalar relativistic (SR) and non-relativistic (NR) DFT calculations attribute about 30% of the mercury-battery voltage to relativity. The obtained percentage is smaller than for the lead-acid battery, but not negligible.

  19. An Assessment of health risk associated with mercury in soil and sediment from East Fork Poplar Creek, Oak Ridge, Tennessee. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Revis, N.; Holdsworth, G.; Bingham, G.; King, A.; Elmore, J.

    1989-04-01

    This report presents results from a study conducted to determine the toxicity of Mercury in soils sediments samples. Mice were fed via diet, soils and sediment, from various locations along the East Fork Poplar creek. Tissue distribution of pollutants was determined at various intervals. The tissue level relative to toxicity was used to determine the effect of a complex matrix on the gastrointestinal absorption and tissue distribution of the pollutants (other pollutants included cadmium and selenium).

  20. Diffusion of hexavalent chromium in chromium-containing slag as affected by microbial detoxification.

    Science.gov (United States)

    Wang, Yunyan; Yang, Zhihui; Chai, Liyuan; Zhao, Kun

    2009-09-30

    An electrochemical method was used to determine the diffusion coefficient of chromium(VI) in chromium-containing slag. A slag plate was prepared from the original slag or the detoxified slag by Achromobacter sp. CH-1. The results revealed that the apparent diffusion coefficient of Cr(VI) was 4.4 x 10(-9)m(2)s(-1) in original slag and 2.62 x 10(-8)m(2)s(-1) in detoxified slag. The results implied that detoxification of chromium-containing slag by Achromobacter sp. CH-1 could enhance Cr(VI) release. Meanwhile, the results of laboratory experiment showed that the residual total Cr(VI) in slag decreased from an initial value of 6.8 mg g(-1) to 0.338 mg g(-1) at the end of the detoxification process. The Cr(VI) released from slag was also reduced by Achromobacter sp. CH-1 strain since water soluble Cr(VI) in the leachate was not detected after 4 days. Therefore, Achromobacter sp. CH-1 has potential application for the bio-detoxification of chromium-containing slag.

  1. [Association between cadmium and breast cancer].

    Science.gov (United States)

    Strumylaite, Loreta; Bogusevicius, Algirdas; Ryselis, Stanislovas; Pranys, Darius; Poskiene, Lina; Kregzdyte, Rima; Abdrachmanovas, Olegas; Asadauskaite, Rūta

    2008-01-01

    Cadmium is a known human lung carcinogen, although some studies indicate a link between cadmium exposure and human breast cancer. The objective of this study was to assess cadmium concentration in breast tissue samples of patients with breast cancer and benign breast tumor. MATERIAL AND METHODS. The concentration of cadmium was determined in breast tissue samples of 21 breast cancer and 19 benign tumor patients. Two samples of breast tissue from each patient, i.e. tumor and normal tissue close to tumor, were taken for the analysis. Cadmium was determined by atomic absorption spectrometry (Perkin-Elmer, Zeeman 3030). RESULTS. In patients with breast cancer, the mean cadmium concentration was 33.1 ng/g (95% CI, 21.9-44.4) in malignant breast tissue and 10.4 ng/g (95% CI, 5.6-15.2) in normal breast tissue (P=0.002). In patients with benign tumor, the corresponding values were 17.5 ng/g (95% CI, 8.4-26.5) and 11.8 ng/g (95% CI, 5.1-18.5) (P=0.3144). There was a statistically significant difference in cadmium concentration between malignant and benign breast tissues (P=0.009). CONCLUSION. The data obtained show that cadmium concentration is significantly higher in malignant breast tissue as compared with normal breast tissue of the same women or benign breast tissue. Further studies are necessary to determine the association between cadmium concentration in malignant breast tissue and estrogen receptor level, and smoking.

  2. Mercury Toolset for Spatiotemporal Metadata

    Science.gov (United States)

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

    2010-06-01

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

  3. Mercury Toolset for Spatiotemporal Metadata

    Science.gov (United States)

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

    2010-01-01

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

  4. The Origin of Mercury

    Science.gov (United States)

    Benz, W.; Anic, A.; Horner, J.; Whitby, J. A.

    Mercury's unusually high mean density has always been attributed to special circumstances that occurred during the formation of the planet or shortly thereafter, and due to the planet's close proximity to the Sun. The nature of these special circumstances is still being debated and several scenarios, all proposed more than 20 years ago, have been suggested. In all scenarios, the high mean density is the result of severe fractionation occurring between silicates and iron. It is the origin of this fractionation that is at the centre of the debate: is it due to differences in condensation temperature and/or in material characteristics (e.g. density, strength)? Is it because of mantle evaporation due to the close proximity to the Sun? Or is it due to the blasting off of the mantle during a giant impact?

  5. Biochemical Effects of Cadmium Exposure and the Potential Pharmacologic Significance of Cadmium Mediated Hydrolase Inhibition

    Science.gov (United States)

    1997-04-18

    increase Cd absorption from the intestines (Larson and Piscator 1971; Itokawa, Abe et al. 197 4; Pond and Walker 1975). Pyridoxine, vitamin B 6 , is...considerations on uptake and retention of cadmium in human kidney cortex. Cadmium in the Environment. L. Friberg, M. Piscator and G. F. Nordberg. Cleveland...Columbia, Missouri, University of Missouri. Larson, S.-E. and M. Piscator (1971). "Effect of cadmium on skeletal tissue in normal and calcium

  6. Pseudo-stir bar hollow fiber solid/liquid phase microextraction combined with anodic stripping voltammetry for determination of lead and cadmium in water samples.

    Science.gov (United States)

    Es'haghi, Zarrin; Hoseini, Hasan Ali; Mohammadi-Nokhandani, Saeed; Ebrahimi, Javad

    2014-11-01

    A new procedure is presented for the determination of low concentrations of lead and cadmium in water samples. Ligand assisted pseudo-stir bar hollow fiber solid/liquid phase microextraction using sol-gel sorbent reinforced with carbon nanotubes was combined with differential pulse anodic stripping voltammetry for simultaneous determination of cadmium and lead in tap water, and Darongar river water samples. In the present work, differential pulse anodic stripping voltammetry (DPASV) using a hanging mercury drop electrode (HMDE) was used in order to determine the ultra trace level of lead and cadmium ions in real samples. This method is based on accumulation of lead and cadmium ions on the electrode using different ligands; Quinolin-8-ol, 5,7-diiodo quinoline-8-ol, 4,5-diphenyl-1H-imidazole-2(3H)-one and 2-{[2-(2-Hydroxy-ethylamino)-ethylamino]-methyl}-phenol as the complexing agent. The optimized conditions were obtained. The relationship between the peak current versus concentration was linear over the range of 0.05-500 ng mL(-1) for Cd (II) and Pb (II). The limits of detection for lead and cadmium were 0.015 ng mL(-1) and 0.012 ng mL(-1), respectively. Under the optimized conditions, the pre-concentration factors are 2440 and 3710 for Cd (II) and Pb (II) in 5 mL of water sample, respectively.

  7. ALUMINUM AND CHROMIUM LEACHING WORKSHOP WHITEPAPER

    Energy Technology Data Exchange (ETDEWEB)

    McCabe, D; Jeff Pike, J; Bill Wilmarth, B

    2007-04-25

    A workshop was held on January 23-24, 2007 to discuss the status of processes to leach constituents from High Level Waste (HLW) sludges at the Hanford and Savannah River Sites. The objective of the workshop was to examine the needs and requirements for the HLW flowsheet for each site, discuss the status of knowledge of the leaching processes, communicate the research plans, and identify opportunities for synergy to address knowledge gaps. The purpose of leaching of non-radioactive constituents from the sludge waste is to reduce the burden of material that must be vitrified in the HLW melter systems, resulting in reduced HLW glass waste volume, reduced disposal costs, shorter process schedules, and higher facility throughput rates. The leaching process is estimated to reduce the operating life cycle of SRS by seven years and decrease the number of HLW canisters to be disposed in the Repository by 1000 [Gillam et al., 2006]. Comparably at Hanford, the aluminum and chromium leaching processes are estimated to reduce the operating life cycle of the Waste Treatment Plant by 20 years and decrease the number of canisters to the Repository by 15,000-30,000 [Gilbert, 2007]. These leaching processes will save the Department of Energy (DOE) billions of dollars in clean up and disposal costs. The primary constituents targeted for removal by leaching are aluminum and chromium. It is desirable to have some aluminum in glass to improve its durability; however, too much aluminum can increase the sludge viscosity, glass viscosity, and reduce overall process throughput. Chromium leaching is necessary to prevent formation of crystalline compounds in the glass, but is only needed at Hanford because of differences in the sludge waste chemistry at the two sites. Improving glass formulations to increase tolerance of aluminum and chromium is another approach to decrease HLW glass volume. It is likely that an optimum condition can be found by both performing leaching and improving

  8. Elemental mercury poisoning probably causes cortical myoclonus.

    Science.gov (United States)

    Ragothaman, Mona; Kulkarni, Girish; Ashraf, Valappil V; Pal, Pramod K; Chickabasavaiah, Yasha; Shankar, Susarla K; Govindappa, Srikanth S; Satishchandra, Parthasarthy; Muthane, Uday B

    2007-10-15

    Mercury toxicity causes postural tremors, commonly referred to as "mercurial tremors," and cerebellar dysfunction. A 23-year woman, 2 years after injecting herself with elemental mercury developed disabling generalized myoclonus and ataxia. Electrophysiological studies confirmed the myoclonus was probably of cortical origin. Her deficits progressed over 2 years and improved after subcutaneous mercury deposits at the injection site were surgically cleared. Myoclonus of cortical origin has never been described in mercury poisoning. It is important to ask patients presenting with jerks about exposure to elemental mercury even if they have a progressive illness, as it is a potentially reversible condition as in our patient.

  9. Mercury and autism: accelerating evidence?

    Science.gov (United States)

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

    2005-10-01

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

  10. Cadmium Toxicity to Ringed Seals (Phoca hispida)

    DEFF Research Database (Denmark)

    Sonne, Christian; Dietz, R.; Riget, F. F.;

    as laboratory mammals. We have studied possible cadmium induced histopathological changes in the kidneys as well as a demineralisation of the skeletal system (DXA-scanning of lumbal vertebraes). No obvious cadmium induced toxic changes were found. Food composition and physiological adaptations may explain......Cadmium concentrations in kidneys from ringed seals (Phoca hispida) from North West Greenland (Qaanaaq) are high. Concentrations range at level known to induce renal toxic effects (mainly tubulopathy) and demineralisation (osteopenia) of the skeletal system (Fanconi's Syndrome) in humans as well...

  11. Safety, absorption, and antioxidant effects of chromium histidine

    Science.gov (United States)

    Supplemental chromium has been shown to be involved in the alleviation of the metabolic syndrome, glucose intolerance, polycystic ovary syndrome, depression, excess body fat, and gestational, steroid-induced, and type 2 diabetes. Chromium amino acid complexes that contained histidine displayed cons...

  12. Mechanisms of bacterial resistance to chromium compounds.

    Science.gov (United States)

    Ramírez-Díaz, Martha I; Díaz-Pérez, César; Vargas, Eréndira; Riveros-Rosas, Héctor; Campos-García, Jesús; Cervantes, Carlos

    2008-06-01

    Chromium is a non-essential and well-known toxic metal for microorganisms and plants. The widespread industrial use of this heavy metal has caused it to be considered as a serious environmental pollutant. Chromium exists in nature as two main species, the trivalent form, Cr(III), which is relatively innocuous, and the hexavalent form, Cr(VI), considered a more toxic species. At the intracellular level, however, Cr(III) seems to be responsible for most toxic effects of chromium. Cr(VI) is usually present as the oxyanion chromate. Inhibition of sulfate membrane transport and oxidative damage to biomolecules are associated with the toxic effects of chromate in bacteria. Several bacterial mechanisms of resistance to chromate have been reported. The best characterized mechanisms comprise efflux of chromate ions from the cell cytoplasm and reduction of Cr(VI) to Cr(III). Chromate efflux by the ChrA transporter has been established in Pseudomonas aeruginosa and Cupriavidus metallidurans (formerly Alcaligenes eutrophus) and consists of an energy-dependent process driven by the membrane potential. The CHR protein family, which includes putative ChrA orthologs, currently contains about 135 sequences from all three domains of life. Chromate reduction is carried out by chromate reductases from diverse bacterial species generating Cr(III) that may be detoxified by other mechanisms. Most characterized enzymes belong to the widespread NAD(P)H-dependent flavoprotein family of reductases. Several examples of bacterial systems protecting from the oxidative stress caused by chromate have been described. Other mechanisms of bacterial resistance to chromate involve the expression of components of the machinery for repair of DNA damage, and systems related to the homeostasis of iron and sulfur.

  13. Observational Approach to Chromium Site Remediation - 13266

    Energy Technology Data Exchange (ETDEWEB)

    Scott Myers, R. [Washington Closure Hanford, 2620 Fermi, Richland, Washington 99354 (United States)

    2013-07-01

    Production reactors at the U.S. Department of Energy's (DOE) Hanford Site in Richland, Washington, required massive quantities of water for reactor cooling and material processing. To reduce corrosion and the build-up of scale in pipelines and cooling systems, sodium dichromate was added to the water feedstock. Spills and other releases at the makeup facilities, as well as leaks from miles of pipelines, have led to numerous areas with chromium-contaminated soil and groundwater, threatening fish populations in the nearby Columbia River. Pump-and-treat systems have been installed to remove chromium from the groundwater, but significant contamination remain in the soil column and poses a continuing threat to groundwater and the Columbia River. Washington Closure Hanford, DOE, and regulators are working on a team approach that implements the observational approach, a strategy for effectively dealing with the uncertainties inherent in subsurface conditions. Remediation of large, complex waste sites at a federal facility is a daunting effort. It is particularly difficult to perform the work in an environment of rapid response to changing field and contamination conditions. The observational approach, developed by geotechnical engineers to accommodate the inherent uncertainties in subsurface conditions, is a powerful and appropriate method for site remediation. It offers a structured means of quickly moving into full remediation and responding to the variations and changing conditions inherent in waste site cleanups. A number of significant factors, however, complicate the application of the observational approach for chromium site remediation. Conceptual models of contamination and site conditions are difficult to establish and get consensus on. Mid-stream revisions to the design of large excavations are time-consuming and costly. And regulatory constraints and contract performance incentives can be impediments to the flexible responses required under the

  14. Atom Lithography with a Chromium Atomic Beam

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wen-Tao; LI Tong-Bao

    2006-01-01

    @@ Direct write atom lithography is a new technique in which resonant light is used to pattern an atomic beam and the nanostructures are formed when the atoms deposit on the substrate. We design an experiment setup to fabricate chromium nanolines by depositing an atomic beam of 52 Cr through an off-resonant laser standing wave with the wavelength of 425.55 nm onto a silicon substrate. The resulting nanolines exhibit a period of 215 ± 3 nm with height of 1 nm.

  15. The fate of chromium during tropical weathering

    DEFF Research Database (Denmark)

    Berger, Alfons; Frei, Robert

    2014-01-01

    We performed a mineral, geochemical and Cr–Sr–Pb isotope study on a laterite profile developed on ca. 540 Ma old tonalitic bedrock in Madagascar with special emphasis on the behavior of chromium during tropical weathering. The observed strong depletions of Ca, Si, and P, and enrichment of Fe and Al......, in the soil, relative to bedrock and underlying saprolite, are the characteristic features pertinent to laterites. The enrichment of Fe in topsoil horizon can be correlated with enrichment of P, and the redox sensitive elements Mn and Cr, and indicates redistribution of these elements related to oxidation...

  16. Bioleaching of chromium from tannery sludge by indigenous Acidithiobacillus thiooxidans.

    Science.gov (United States)

    Wang, Yuan-Shan; Pan, Zhi-Yan; Lang, Jian-Min; Xu, Jian-Miao; Zheng, Yu-Guo

    2007-08-17

    Chromium in tannery sludge will cause serious environmental problems and is toxic to organisms. The acidophilic sulfur-oxidizing Acidithiobacillus thiooxidans can leach heavy metals form urban and industrial wastes. This study examined the ability of an indigenous sulfur-oxidizing A. thiooxidans to leach chromium from tannery sludge. The results showed that the pH of sludge mixture inoculated with the indigenous A. thiooxidans decreased to around 2.0 after 4 days. After 6 days incubation in shaking flasks at 30 degrees C and 160 rpm, up to 99% of chromium was solubilized from tannery sludge. When treated in a 2-l bubble column bioreactor for 5 days at 30 degrees C and aeration of 0.5 vvm, 99.7% of chromium was leached from tannery sludge. The results demonstrated that chromium in tannery sludge can be efficiently leached by the indigenous A. thiooxidans.

  17. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2005-06-01

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

  18. Mercury Methylation and Environmental Effects of Inactive Mercury Mines in the Circum-Pacific Region

    Science.gov (United States)

    Gray, J. E.

    2001-05-01

    Mercury mines worldwide contain of some the highest concentrations of mercury on earth, and as a result of local mercury contamination, these mines represent areas of environmental concern when mine-drainage enters downstream aquatic systems. The most problematic aspect of mine site mercury contamination is the conversion of inorganic mercury to highly toxic organic mercury compounds, such as methylmercury, and their subsequent uptake by aquatic organisms in surrounding ecosystems. Mercury and methylmercury concentrations were measured in sediment and water samples collected from several inactive mercury mines in Nevada, Alaska, and the Philippines, which are part of the circum-Pacific mineral belt. The mines studied represent different mercury deposit types and sizes, and climatic settings. Geochemical data collected from these mines indicate that areas surrounding hot-springs type mercury deposits generally have lower methylmercury concentrations than silica-carbonate mercury deposits. In hot-springs mercury deposits in Nevada and Alaska, ore is dominantly cinnabar with few acid-water generating minerals such as pyrite, and as a result, mine-water drainage has near neutral pH in which there is low solubility of mercury. Conversely, silica-carbonate deposits, such as Palawan, Philippines, contain abundant cinnabar and pyrite, and the resultant acidic-mine drainage generally has higher concentrations of mercury and methylmercury. Additional factors such as the proximity of mercury mines to wetlands, climatic effects, or mine wastes containing highly soluble mercury compounds potentially enhance mercury methylation. The Palawan mercury mine may be a unique example where several adverse environmental factors produced local mercury contamination, high mercury methylation, fish contamination, and mercury poisoning of humans that consumed these contaminated fish.

  19. The Theory for the Mechanism of Chromium Plating: The Theory for the Physical Characteristics of Chromium Plate

    Science.gov (United States)

    1947-01-01

    deposits arc pro- duced as the coll potential is successively raised. The sulfato ion "hus has an extremely important effect in the chromium plating...and sulfato iDU in the bath wore then used in an attempt to obtain more satisfactory hexagonal chromium deposits. The data obtained are summarUod

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

    Science.gov (United States)

    Siegel, S. M.

    1973-01-01

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

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

    DEFF Research Database (Denmark)

    Rasmussen, Lasse Dam; Sørensen, Søren Johannes

    1998-01-01

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

  2. RISK ASSESSMENT AND MANAGEMENT OF ENVIRONMENTAL CADMIUM

    Science.gov (United States)

    Cadmium consumed in foods grown on soils contaminated by industrial Cd+Zn discharge has caused renal tubular dysfunction in exposed humans in discrete situations. However, lack of understanding about environmental Cd has caused wide concern that generalpopulations may...

  3. Dissolution of chromium in sulfuric acid

    Directory of Open Access Journals (Sweden)

    J. P. POPIC

    2002-11-01

    Full Text Available By combining electrochemical corrosion rate measurements and spectrophotometric analysis of the electrolyte it was shown that at room temperature chromium dissolves in deaerated 0.1 M Na2SO4 + H2SO4 (pH 1 solution as Cr(II and Cr(III ions in he ratio Cr(II : Cr(III @ 7 : 1. This process was stable over 4 h without any detectable change. The total corrosion rate of chromium calculated from the analytical data is about 12 times higher, than that determined electrochemically by cathodic Tafel line extrapolation to the corrosion potential. This finding was confirmed by applying the weight-loss method for the determination of the corrosion rate. This enormous difference between these experimentally determined corrosion rates can be explained by the rather fast, “anomalous” dissolution process proposed by Kolotyrkin and coworkers (chemical reaction of Cr with H2O molecules occurring simultaneously with the electrochemical corrosion process.

  4. Historical methyl mercury in San Francisco Bay

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — San Francisco Bay, California is considered a mercury-impaired watershed. Elevated concentrations of mercury are found in water and sediment as well as fish and...

  5. Some Aspects of Sealed Nickel Cadmium Cells

    Directory of Open Access Journals (Sweden)

    P. K. Saha

    1967-11-01

    Full Text Available Sealed Nickel Cadmium Cell system is termed till today as the most reliable power pack for electronic apparatus specially in low temperature use. This paper brings out the development and production of sealed nickel cadmium cells of pocket plate construction. The author who has gained experience in production of Ni-Cd cells in East Germany discusses also the major problems faced by the battery manufactures of to-day.

  6. Method for the removal and recovery of mercury

    Energy Technology Data Exchange (ETDEWEB)

    Easterly, C.E.; Vass, A.A.; Tyndall, R.L.

    1997-01-28

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

  7. Method for the removal and recovery of mercury

    Energy Technology Data Exchange (ETDEWEB)

    Easterly, Clay E. (Knoxville, TN); Vass, Arpad A. (Oak Ridge, TN); Tyndall, Richard L. (Clinton, TN)

    1997-01-01

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

  8. Screening micro-organisms for cadmium absorption from aqueous solution and cadmium absorption properties of Arthrobacter nicotianae.

    Science.gov (United States)

    Tsuruta, Takehiko; Umenai, Daishi; Hatano, Tomonobu; Hirajima, Tsuyoshi; Sasaki, Keiko

    2014-01-01

    To obtain basic information on how microbial cells absorb cadmium from aqueous solution, we examined cadmium absorption in various micro-organisms. Of 51 micro-organism strains tested, we found that some Gram-positive bacteria, such as, Arthrobacter nicotianae and Bacillus subtilis, and some actinomycetes, such as, Streptomyces flavoviridis and S. levoris were highly capable of absorbing cadmium from an aqueous solution. A. nicotianae absorbed the largest amount of cadmium, over 800 μmol cadmium per gram of dry wt. cells. However, cadmium absorption by A. nicotianae was affected by the solution pH, cadmium concentration, and cell density. The absorption of cadmium was very rapid. Some factors that affected cadmium absorption by A. nicotianae cells were also discussed.

  9. Mercury - the hollow planet

    Science.gov (United States)

    Rothery, D. A.

    2012-04-01

    Mercury is turning out to be a planet characterized by various kinds of endogenous hole (discounting impact craters), which are compared here. These include volcanic vents and collapse features on horizontal scales of tens of km, and smaller scale depressions ('hollows') associated with bright crater-floor deposits (BCFD). The BCFD hollows are tens of metres deep and kilometres or less across and are characteristically flat-floored, with steep, scalloped walls. Their form suggests that they most likely result from removal of surface material by some kind of mass-wasting process, probably associated with volume-loss caused by removal (via sublimation?) of a volatile component. These do not appear to be primarily a result of undermining. Determining the composition of the high-albedo bluish surface coating in BCFDs will be a key goal for BepiColombo instruments such as MIXS (Mercury Imaging Xray Spectrometer). In contrast, collapse features are non-circular rimless pits, typically on crater floors (pit-floor craters), whose morphology suggests collapse into void spaces left by magma withdrawal. This could be by drainage of either erupted lava (or impact melt) or of shallowly-intruded magma. Unlike the much smaller-scale BCFD hollows, these 'collapse pit' features tend to lack extensive flat floors and instead tend to be close to triangular in cross-section with inward slopes near to the critical angle of repose. The different scale and morphology of BCFD hollows and collapse pits argues for quite different modes of origin. However, BCFD hollows adjacent to and within the collapse pit inside Scarlatti crater suggest that the volatile material whose loss was responsible for the growth of the hollows may have been emplaced in association with the magma whose drainage caused the main collapse. Another kind of volcanic collapse can be seen within a 25 km-wide volcanic vent outside the southern rim of the Caloris basin (22.5° N, 146.1° E), on a 28 m/pixel MDIS NAC image

  10. Cadmium exposure and breast cancer risk.

    Science.gov (United States)

    McElroy, Jane A; Shafer, Martin M; Trentham-Dietz, Amy; Hampton, John M; Newcomb, Polly A

    2006-06-21

    Cadmium, a highly persistent heavy metal, has been categorized as a probable human carcinogen by the U.S. Environmental Protection Agency. Primary exposure sources include food and tobacco smoke. We carried out a population-based case-control study of 246 women, aged 20-69 years, with breast cancer and 254 age-matched control subjects. We measured cadmium levels in urine samples by inductively coupled plasma mass spectrometry and conducted interviews by telephone to obtain information on known breast cancer risk factors. Odds ratios (ORs) and 95% confidence intervals (CIs) for breast cancer by creatinine-adjusted cadmium levels were calculated by multivariable analysis. Statistical tests were two-sided. Women in the highest quartile of creatinine-adjusted cadmium level (> or = 0.58 microg/g) had twice the breast cancer risk of those in the lowest quartile (cadmium level (P(trend) = .01). Based on this study, the absolute risk difference is 45 (95% CI = 0 to 77) per 100,000 given an overall breast cancer rate of 124 per 100,000. Whether increased cadmium is a causal factor for breast cancer or reflects the effects of treatment or disease remains to be determined.

  11. Electrochemical modification of chromium surfaces using 4-nitro- and4-fluorobenzenediazonium salts

    DEFF Research Database (Denmark)

    Hinge, Mogens; Cecatto, Marcel; Kingshott, Peter;

    2009-01-01

    Chromium surfaces can be electrografted with organic surface films using 4-nitro- or 4-fluorobenzenediazonium salts, despite the fact that the surfaces are covered with a protective chromium oxide layer......Chromium surfaces can be electrografted with organic surface films using 4-nitro- or 4-fluorobenzenediazonium salts, despite the fact that the surfaces are covered with a protective chromium oxide layer...

  12. Standard Specification for Pressure Consolidated Powder Metallurgy Iron-Nickel-Chromium-Molybdenum (UNS N08367), Nickel-Chromium-Molybdenum-Columbium (Nb) (UNS N06625), Nickel-Chromium-Iron Alloys (UNS N06600 and N06690), and Nickel-Chromium-Iron-Columbium-Molybdenum (UNS N07718) Alloy Pipe Flanges, Fittings, Valves, and Parts

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2015-01-01

    Standard Specification for Pressure Consolidated Powder Metallurgy Iron-Nickel-Chromium-Molybdenum (UNS N08367), Nickel-Chromium-Molybdenum-Columbium (Nb) (UNS N06625), Nickel-Chromium-Iron Alloys (UNS N06600 and N06690), and Nickel-Chromium-Iron-Columbium-Molybdenum (UNS N07718) Alloy Pipe Flanges, Fittings, Valves, and Parts

  13. Preservation of samples for dissolved mercury

    Science.gov (United States)

    Hamlin, S.N.

    1989-01-01

    Water samples for dissolved mercury requires special treatment because of the high chemical mobility and volatility of this element. Widespread use of mercury and its compounds has provided many avenues for contamination of water. Two laboratory tests were done to determine the relative permeabilities of glass and plastic sample bottles to mercury vapor. Plastic containers were confirmed to be quite permeable to airborne mercury, glass containers were virtually impermeable. Methods of preservation include the use of various combinations of acids, oxidants, and complexing agents. The combination of nitric acid and potassium dichromate successfully preserved mercury in a large variety of concentrations and dissolved forms. Because this acid-oxidant preservative acts as a sink for airborne mercury and plastic containers are permeable to mercury vapor, glass bottles are preferred for sample collection. To maintain a healthy work environment and minimize the potential for contamination of water samples, mercury and its compounds are isolated from the atmosphere while in storage. Concurrently, a program to monitor environmental levels of mercury vapor in areas of potential contamination is needed to define the extent of mercury contamination and to assess the effectiveness of mercury clean-up procedures.Water samples for dissolved mercury require special treatment because of the high chemical mobility and volatility of this element. Widespread use of mercury and its compounds has provided many avenues for contamination of water. Two laboratory tests were done to determine the relative permeabilities of glass and plastic sample bottles to mercury vapor. Plastic containers were confirmed to be quite permeable to airborne mercury, glass containers were virtually impermeable. Methods of preservation include the use of various combinations of acids, oxidants, and complexing agents. The combination of nitric acid and potassium dichromate successfully preserved mercury in a

  14. Phytoremediation of Ionic and Methyl Mercury Pollution

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, Richard B.

    2004-12-01

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

  15. Mercury Concentration in Environmental Samples of Malaysia

    OpenAIRE

    SAKAMOTO, Hayao; Ichikawa, Toshihiro; TOMIYASU, Takashi; SATO, Masanori

    2004-01-01

    The concentration and distribution of mercury in environmental samples (sea water, rock, sea sand, sediment, soil, fish and etc.) taken from various coastal sea areas and its ambient area in Malaysia were investigated. Mercury in environmental samples was subjected to the reduction-vaporization using of tin (II) chloride and heating-vaporization method. The mercury vapor was concentrated with a porous gold collector. Afterwards, mercury vapor evolved from the heated collector was determined b...

  16. Study of the environmental cycling of mercury

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Frades, J.P.; Hildebrand, S.G.; Huckabee, J.W.; Murias, B.; Diaz, F.S.; Wilson, R.H.

    1977-01-01

    A study of mercury in the environment is under way near the mercury mine at Almaden, Spain. The main aspects of the project are: ecology; atmospheric monitoring; and human studies. The mercury deposit at Almaden is described. The liquid effluent from the mine and smelter contains high concentrations of mercury that pollute nearby rivers. Sample collection and analytical methods used in the ecological survey are reviewed. Ecological experiments are considered. Air monitoring studies and human studies currently being performed are assessed. (1 map)

  17. Mercury Continuous Emmission Monitor Calibration

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-03-12

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

  18. Workshop on effects of chromium coating on Nb{sub 3}Sn superconductor strand: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-12

    This report discusses the following topics: Chromium coating on superconductor strand -- an overview; technology of chromium plating; comparison of wires plated by different platers; search for chromium in copper; strand manufactures` presentations; chromium plating at the Lawrence Livermore National Laboratory; a first look at a chromium plating process development project tailored for T.P.X. and I.T.E.R. strand; and influence of chromium diffusion and related phenomena on the reference ratios of bare and chromium plated Nb{sub 3}Sn strand.

  19. Mercury poisoning: an unusual cause of polyarthritis.

    Science.gov (United States)

    Karataş, G K; Tosun, A K; Karacehennem, E; Sepici, V

    2002-02-01

    Mercury is a toxic metal that is widely used in everyday life. It has organic and inorganic forms that are both toxic. As acute mercury poisoning is uncommon, diagnosis is difficult if the exposure is not manifest. It has usually a slow onset and non-specific symptoms. In this paper we report a patient who developed polyarthritis after mercury exposure.

  20. 40 CFR 721.10068 - Elemental mercury.

    Science.gov (United States)

    2010-07-01

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