Sample records for cadmium iron manganese

  1. Characterizing the role of rice NRAMP5 in Manganese, Iron and Cadmium Transport

    PubMed Central

    Ishimaru, Yasuhiro; Takahashi, Ryuichi; Bashir, Khurram; Shimo, Hugo; Senoura, Takeshi; Sugimoto, Kazuhiko; Ono, Kazuko; Yano, Masahiro; Ishikawa, Satoru; Arao, Tomohito; Nakanishi, Hiromi; Nishizawa, Naoko K.

    2012-01-01

    Metals like manganese (Mn) and iron (Fe) are essential for metabolism, while cadmium (Cd) is toxic for virtually all living organisms. Understanding the transport of these metals is important for breeding better crops. We have identified that OsNRAMP5 contributes to Mn, Fe and Cd transport in rice. OsNRAMP5 expression was restricted to roots epidermis, exodermis, and outer layers of the cortex as well as in tissues around the xylem. OsNRAMP5 localized to the plasma membrane, and complemented the growth of yeast strains defective in Mn, Fe, and Cd transport. OsNRAMP5 RNAi (OsNRAMP5i) plants accumulated less Mn in the roots, and less Mn and Fe in shoots, and xylem sap. The suppression of OsNRAMP5 promoted Cd translocation to shoots, highlighting the importance of this gene for Cd phytoremediation. These data reveal that OsNRAMP5 contributes to Mn, Cd, and Fe transport in rice and is important for plant growth and development. PMID:22368778

  2. Some factors influencing cadmium-manganese interaction in adult rats

    SciTech Connect

    Gruden, N.; Matausic, S. (Univ. of Zagreb (Yugoslavia))

    1989-07-01

    Recent data show that even a low dose of cadmium (20 {mu}g/day/rat) significantly suppresses manganese transduodenal transport when administered during a three-day period. The inhibitory effect of cadmium upon manganese absorption is enhanced by concurrently administered iron-fortified milk diet. This suggests that the (synergistic) action of cadmium and iron upon manganese and the competition between these (three) ions in the intestine depend on their relative concentrations and affinity for the binding sites within the intestinal mucosa. For this reason the authors considered it worthwhile examining whether this inhibitory effect of cadmium would be affected by simultaneously administered manganese-fortified milk. Since the absorption of heavy metals and, at the same time, the demand for manganese is higher in the young than in the old animals, they also studied how this interaction depends upon the animals' age and sex and whether it is the same in the whole small intestine.

  3. Inductively coupled plasma atomic fluorescence spectrometric determination of cadmium, copper, iron, lead, manganese and zinc

    USGS Publications Warehouse

    Sanzolone, R.F.

    1986-01-01

    An inductively coupled plasma atomic fluorescence spectrometric method is described for the determination of six elements in a variety of geological materials. Sixteen reference materials are analysed by this technique to demonstrate its use in geochemical exploration. Samples are decomposed with nitric, hydrofluoric and hydrochloric acids, and the residue dissolved in hydrochloric acid and diluted to volume. The elements are determined in two groups based on compatibility of instrument operating conditions and consideration of crustal abundance levels. Cadmium, Cu, Pb and Zn are determined as a group in the 50-ml sample solution under one set of instrument conditions with the use of scatter correction. Limitations of the scatter correction technique used with the fluorescence instrument are discussed. Iron and Mn are determined together using another set of instrumental conditions on a 1-50 dilution of the sample solution without the use of scatter correction. The ranges of concentration (??g g-1) of these elements in the sample that can be determined are: Cd, 0.3-500; Cu, 0.4-500; Fe, 85-250 000; Mn, 45-100 000; Pb, 5-10 000; and Zn, 0.4-300. The precision of the method is usually less than 5% relative standard deviation (RSD) over a wide concentration range and acceptable accuracy is shown by the agreement between values obtained and those recommended for the reference materials.

  4. Low iron stores are related to higher blood concentrations of manganese, cobalt and cadmium in non-smoking, Norwegian women in the HUNT 2 study

    SciTech Connect

    Margrete Meltzer, Helle, E-mail: helle.margrete.meltzer@fhi.no [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Lise Brantsaeter, Anne [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway)] [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Borch-Iohnsen, Berit [Institute of Basic Medical Sciences, Department of Nutrition, University of Oslo, PO Box 1046 Blindern, N-0316 Oslo (Norway)] [Institute of Basic Medical Sciences, Department of Nutrition, University of Oslo, PO Box 1046 Blindern, N-0316 Oslo (Norway); Ellingsen, Dag G. [National Institute of Occupational Health, PO Box 8149 Dep, N-0033 Oslo (Norway)] [National Institute of Occupational Health, PO Box 8149 Dep, N-0033 Oslo (Norway); Alexander, Jan [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway)] [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Thomassen, Yngvar [National Institute of Occupational Health, PO Box 8149 Dep, N-0033 Oslo (Norway)] [National Institute of Occupational Health, PO Box 8149 Dep, N-0033 Oslo (Norway); Stigum, Hein [Division of Epidemiology, Department of Chronic Diseases, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway)] [Division of Epidemiology, Department of Chronic Diseases, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Ydersbond, Trond A. [Statistics Norway, P.Box 8131 Dep, N-0033 Oslo (Norway)] [Statistics Norway, P.Box 8131 Dep, N-0033 Oslo (Norway)

    2010-07-15

    Low iron (Fe) stores may influence absorption or transport of divalent metals in blood. To obtain more knowledge about such associations, the divalent metal ions cadmium (Cd), manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn) and lead (Pb) and parameters of Fe metabolism (serum ferritin, haemoglobin (Hb) and transferrin) were investigated in 448 healthy, menstruating non-smoking women, age 20-55 years (mean 38 years), participating in the Norwegian HUNT 2 study. The study population was stratified for serum ferritin: 257 were iron-depleted (serum ferritin <12 {mu}g/L) and 84 had iron deficiency anaemia (serum ferritin <12 {mu}g/L and Hb<120 g/L). The low ferritin group had increased blood concentrations of Mn, Co and Cd but normal concentrations of Cu, Zn and Pb. In multiple regression models, ferritin emerged as the main determinant of Mn, Co and Cd (p<0.001), while no significant associations with Cu, Zn and Pb were found. Adjusted r{sup 2} for the models were 0.28, 0.48 and 0.34, respectively. Strong positive associations between blood concentrations of Mn, Co and Cd were observed, also when controlled for their common association with ferritin. Apart from these associations, the models showed no significant interactions between the six divalent metals studied. Very mild anaemia (110{<=}Hb<120 g/L) did not seem to have any effect independent of low ferritin. Approximately 26% of the women with iron deficiency anaemia had high concentrations of all of Mn, Co and Cd as opposed to 2.3% of iron-replete subjects. The results confirm that low serum ferritin may have an impact on body kinetics of certain divalent metal ions, but not all. Only a fraction of women with low iron status exhibited an increased blood concentration of divalent metals, providing indication of complexities in the body's handling of these metals.

  5. Low iron stores are related to higher blood concentrations of manganese, cobalt and cadmium in non-smoking, Norwegian women in the HUNT 2 study.

    PubMed

    Meltzer, Helle Margrete; Brantsaeter, Anne Lise; Borch-Iohnsen, Berit; Ellingsen, Dag G; Alexander, Jan; Thomassen, Yngvar; Stigum, Hein; Ydersbond, Trond A

    2010-07-01

    Low iron (Fe) stores may influence absorption or transport of divalent metals in blood. To obtain more knowledge about such associations, the divalent metal ions cadmium (Cd), manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn) and lead (Pb) and parameters of Fe metabolism (serum ferritin, haemoglobin (Hb) and transferrin) were investigated in 448 healthy, menstruating non-smoking women, age 20-55 years (mean 38 years), participating in the Norwegian HUNT 2 study. The study population was stratified for serum ferritin: 257 were iron-depleted (serum ferritin < 12 microg/L) and 84 had iron deficiency anaemia (serum ferritin < 12 microg/L and Hb < 120 g/L). The low ferritin group had increased blood concentrations of Mn, Co and Cd but normal concentrations of Cu, Zn and Pb. In multiple regression models, ferritin emerged as the main determinant of Mn, Co and Cd (p < 0.001), while no significant associations with Cu, Zn and Pb were found. Adjusted r(2) for the models were 0.28, 0.48 and 0.34, respectively. Strong positive associations between blood concentrations of Mn, Co and Cd were observed, also when controlled for their common association with ferritin. Apart from these associations, the models showed no significant interactions between the six divalent metals studied. Very mild anaemia (110 < or = Hb < 120 g/L) did not seem to have any effect independent of low ferritin. Approximately 26% of the women with iron deficiency anaemia had high concentrations of all of Mn, Co and Cd as opposed to 2.3% of iron-replete subjects. The results confirm that low serum ferritin may have an impact on body kinetics of certain divalent metal ions, but not all. Only a fraction of women with low iron status exhibited an increased blood concentration of divalent metals, providing indication of complexities in the body's handling of these metals. PMID:20381026

  6. Iron and manganese in lakes

    Microsoft Academic Search

    William Davison

    1993-01-01

    The role of redox processes in determining the chemistry of iron and manganese is considered systematically. Both metals have soluble reduced forms and insoluble oxyhydroxides which are readily interconverted in the vicinity of a redox boundary. Although the oxyhydroxides are dominant in well-oxygenated waters, measureable concentrations of Fe(II) and Mn(II) can be observed, especially where photochemical reduction occurs. Differences in

  7. Monitoring Trace Metal Levels in Yozgat-Turkey: Copper, Iron, Nickel, Cobalt, Lead, Cadmium, Manganese and Chromium Levels in Stream Sediments

    Microsoft Academic Search

    M. Soylak; U. Divrikli; S. Saracoglu; L. Elci

    In the presented study, the concentrations of some heavy metal ions in bottom sediment samples col- lected from streams around Yozgat-Turkey in December 1998 and October 1999 were determined by flame atomic absorption spectrometry (FAAS) after leaching with aqua regia. Copper, iron, nickel, cobalt, lead, manganese and chromium levels in the sediment samples were found in the range of 10.4-16.7

  8. Drinking Water Problems: Iron and Manganese

    E-print Network

    Dozier, Monty; McFarland, Mark L.

    2004-02-20

    Iron and manganese can give water an unpleasant taste, odor and color. In this publication you'll learn how to know whether your water contains iron or manganese and how to eliminate these contaminants with various treatment methods such as aeration...

  9. Blood metal concentrations of manganese, lead, and cadmium in relation to serum ferritin levels in ohio residents.

    PubMed

    Kim, Yangho; Lobdell, Danelle T; Wright, Chris W; Gocheva, Vihra V; Hudgens, Edward; Bowler, Rosemarie M

    2015-05-01

    The objectives of this study were to assess ferritin-specific profiles of blood metal concentrations such as manganese, lead, and cadmium and to evaluate whether ferritin may affect the behavior of the blood metals in relation to menstruation, menopause, or sex in Ohio residents. Recruited participants included residents from Marietta, East Liverpool, and Mt. Vernon, OH, USA, who were aged 30-75 years and lived at least 10 years in their respective town. The levels of the neurotoxic metals such as manganese, cadmium, and lead were assayed in whole blood. Serum was analyzed for ferritin level [as a biomarker of iron (Fe) status]. An association between blood metal concentrations and independent variables (age, serum ferritin, manganese exposure status, and sex) by multiple regression analysis was assessed, controlling for various covariates such as BMI, educational level, smoking, and alcohol drinking status. Overall, the geometric means of blood manganese, cadmium, and lead levels of all participants (n?=?276) were 9.307 ?g/L, 0.393 ?g/L, and 1.276 ?g/dL, respectively. Log serum ferritin concentrations were inversely associated with log blood manganese concentration (??=?-0.061 log ferritin and ??=?0.146 categorical ferritin) and log blood cadmium concentrations (??=?-0.090 log ferritin and ??=?0.256 categorical ferritin). Log serum ferritin concentrations were not associated with log blood lead concentrations. Variables of age, sex, and exposure status were not associated with log manganese concentrations; however, log blood cadmium concentrations were higher in older population, women, and smokers. Log blood lead concentrations were higher in older population, men, and postmenopausal women. Our study showed that iron deficiency is associated with increased levels of blood manganese and cadmium, but not blood lead, in Ohio residents. These metals showed different toxicokinetics in relation to age, sex, and menopausal status despite similar relationships between ferritin and metal concentrations. PMID:25578336

  10. Formation of nickel, cobalt, manganese and cadmium ferrocyanides.

    PubMed

    Bellomo, A; De Marco, D; Casale, A

    1972-10-01

    Potentiometric and solubility studies have been made of the ferrocyanides of nickel, cobalt, manganese(II) and cadmium both in the presence and absence of potassium. The K(3p),DeltaG degrees , DeltaH degrees and DeltaS degrees values are reported. PMID:18961181

  11. Iron Deficiency is Not Associated with Increased Blood Cadmium in Infants

    PubMed Central

    2014-01-01

    Objectives To determine whether blood cadmium concentration is elevated in iron-deficient infants. Methods Blood cadmium and serum ferritin concentrations, serum iron/total iron-binding capacity (Fe/TIBC) and complete blood counts were measured in 31 iron deficient and 36 control infants, aged 6–24 months. All 31 iron-deficient infants received iron supplementation for 1–6 months. Results Blood cadmium concentrations were measured again in 19 of the iron deficient infants after their ferritin levels returned to the normal range. The mean blood cadmium concentration did not differ significantly in iron deficient and control infants. The mean blood cadmium concentration in the 19 iron-deficient infants was not significantly altered by ferric hydroxide treatment, while their hemoglobin, ferritin, and Fe/TIBC (%) concentrations were significantly higher after than before treatment. Conclusion These findings indicate that iron deficiency does not increase blood cadmium concentrations in infants, in contrast with the effects of iron deficiency on manganese and lead concentrations. PMID:24513153

  12. First principle study of manganese doped cadmium sulphide sheet

    NASA Astrophysics Data System (ADS)

    Kumar, Sanjeev; Kumar, Ashok; Ahluwalia, P. K.

    2014-04-01

    First-principle electronic structure calculations for cadmium sulphide (CdS) sheet in hexagonal phase, with Manganese substitution and addition, as well as including the Cd defects, are investigated. The lattice constants calculated for CdS sheet agrees fairly well with results reported for thin films experimentally. The calculations of total spin density of states and partial density of states in different cases shows substantial magnetic dipole moments acquired by the sheet. A magnetic dipole moment 5.00612 ?B and band gap of the order 1 eV are found when cadmium atom is replaced by Manganese. The magnetism acquired by the sheet makes it functionally important candidate in many applications.

  13. First principle study of manganese doped cadmium sulphide sheet

    SciTech Connect

    Kumar, Sanjeev, E-mail: drskumar11@gmail.com [Department of Physics, St. Bede's College, Shimla-171002 (India); Kumar, Ashok; Ahluwalia, P. K. [Department of Physics, Himachal Pradesh University, Shimla-171005 (India)

    2014-04-24

    First-principle electronic structure calculations for cadmium sulphide (CdS) sheet in hexagonal phase, with Manganese substitution and addition, as well as including the Cd defects, are investigated. The lattice constants calculated for CdS sheet agrees fairly well with results reported for thin films experimentally. The calculations of total spin density of states and partial density of states in different cases shows substantial magnetic dipole moments acquired by the sheet. A magnetic dipole moment 5.00612 ?{sub B} and band gap of the order 1 eV are found when cadmium atom is replaced by Manganese. The magnetism acquired by the sheet makes it functionally important candidate in many applications.

  14. 40 CFR 721.10529 - Cobalt iron manganese oxide, carboxylic acid-modified (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 2014-07-01 false Cobalt iron manganese oxide, carboxylic acid-modified...Substances § 721.10529 Cobalt iron manganese oxide, carboxylic acid-modified...identified generically as cobalt iron manganese oxide, carboxylic...

  15. 40 CFR 721.10529 - Cobalt iron manganese oxide, carboxylic acid-modified (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 2013-07-01 false Cobalt iron manganese oxide, carboxylic acid-modified...Substances § 721.10529 Cobalt iron manganese oxide, carboxylic acid-modified...identified generically as cobalt iron manganese oxide, carboxylic...

  16. A zinc-resistant human epithelial cell line is impaired in cadmium and manganese import

    SciTech Connect

    Rousselet, Estelle [CEA, DSV, IRTSV, Laboratoire de Chimie et Biologie des Metaux, Grenoble (France)]|[LCBM, CNRS UMR5249, Grenoble (France); Universite Joseph Fourier, Grenoble (France); Richaud, Pierre [CEA, DSV, IBEB, SBVME, LB3M, Saint-Paul-lez-Durance (France)]|[LB3M, CNRS UMR 6191, Saint-Paul-lez-Durance (France)]|[Universite Aix-Marseille (France); Douki, Thierry; Chantegrel, Jocelyne Garcia; Favier, Alain [Universite Joseph Fourier, Grenoble (France)]|[CEA, DSM, INaC/SCIB, Laboratoire 'Lesions des Acides Nucleiques', Grenoble (France); Bouron, Alexandre [CEA, DSV, IRTSV, Laboratoire de Chimie et Biologie des Metaux, Grenoble (France)]|[LCBM, CNRS UMR5249, Grenoble (France)]|[Universite Joseph Fourier, Grenoble (France); Moulis, Jean-Marc [CEA, DSV, IRTSV, Laboratoire de Chimie et Biologie des Metaux, Grenoble (France)]|[LCBM, CNRS UMR5249, Grenoble (France)]|[Universite Joseph Fourier, Grenoble (France)], E-mail: jean-marc.moulis@cea.fr

    2008-08-01

    A human epithelial cell line (HZR) growing with high zinc concentrations has been analyzed for its ability to sustain high cadmium concentrations. Exposure to up to 200 {mu}M of cadmium acetate for 24 h hardly impacted viability, whereas most of parental HeLa cells were killed by less than 10 {mu}M of cadmium. Upon challenge by 35 fold higher cadmium concentrations than HeLa cells, HZR cells did not display increased DNA damage, increased protein oxidation, or changed intracellular cadmium localization. Rather, the main cause of resistance against cadmium was by avoiding cadmium entry into cells, which differs from that against zinc as the latter accumulates inside cells. The zinc-resistant phenotype of these cells was shown to also impair extracellular manganese uptake. Manganese and cadmium competed for entry into HeLa cells. Probing formerly identified cadmium or manganese transport systems in different animal cells did not evidence any significant change between HeLa and HZR cells. These results reveal zinc adaptation influences manganese and cadmium cellular traffic and they highlight previously unknown connections among homeostasis of divalent metals.

  17. A zinc-resistant human epithelial cell line is impaired in cadmium and manganese import.

    PubMed

    Rousselet, Estelle; Richaud, Pierre; Douki, Thierry; Chantegrel, Jocelyne Garcia; Favier, Alain; Bouron, Alexandre; Moulis, Jean-Marc

    2008-08-01

    A human epithelial cell line (HZR) growing with high zinc concentrations has been analyzed for its ability to sustain high cadmium concentrations. Exposure to up to 200 microM of cadmium acetate for 24 h hardly impacted viability, whereas most of parental HeLa cells were killed by less than 10 microM of cadmium. Upon challenge by 35 fold higher cadmium concentrations than HeLa cells, HZR cells did not display increased DNA damage, increased protein oxidation, or changed intracellular cadmium localization. Rather, the main cause of resistance against cadmium was by avoiding cadmium entry into cells, which differs from that against zinc as the latter accumulates inside cells. The zinc-resistant phenotype of these cells was shown to also impair extracellular manganese uptake. Manganese and cadmium competed for entry into HeLa cells. Probing formerly identified cadmium or manganese transport systems in different animal cells did not evidence any significant change between HeLa and HZR cells. These results reveal zinc adaptation influences manganese and cadmium cellular traffic and they highlight previously unknown connections among homeostasis of divalent metals. PMID:18433815

  18. Topologically Constrained Manganese(III) and Iron(III) Complexes of Two Cross-Bridged Tetraazamacrocycles

    E-print Network

    Hubin, Tim

    Topologically Constrained Manganese(III) and Iron(III) Complexes of Two Cross prepared by the chemical oxidation of the divalent manganese and iron analogues. The ligands are ethylene for the complexes with manganese(III). The manganese chemistry of 1 was studied in depth. The dichloro manganese

  19. Manganese, Iron, and sulfur cycling in Louisiana continental shelf sediments

    EPA Science Inventory

    Sulfate reduction is considered the primary pathway for organic carbon remineralization on the northern Gulf of Mexico Louisiana continental shelf (LCS) where bottom waters are seasonally hypoxic, yet limited information is available on the importance of iron and manganese cyclin...

  20. Oxygen toxicity in Streptococcus mutans: manganese, iron and superoxide dismutase

    SciTech Connect

    Martin, M.E.; Strachan, R.C.; Aranha, H.; Evans, S.L.; Salin, M.L.; Welch, B.; Arceneaux, J.E.L.; Byers, B.R.

    1984-07-01

    When cultured anaerobically in a chemically defined medium that was treated with Chelex-100 to lower its trace metal content, Streptococcus mutans OMZ176 had no apparent requirement for manganese or iron. Manganese or iron was necessary for aerobic cultivation in deep static cultures. During continuous aerobic cultivation in a stirred chemostat, iron did not support the growth rate achieved with manganese. Since the dissolved oxygen level in the chemostat cultures was higher than the final level in the static cultures, manganese may be required for growth at elevated levels. In medium supplemented with manganese, cells grown anaerobically contained a low level of superoxide dismutase (SOD) activity; aerobic cultivation increased SOD activity at least threefold. In iron-supplemented medium, cells grown anaerobically also had low SOD activity; aerobic incubation resulted in little increase in SOD activity. Polyacrylamide gel electrophoresis of the cell extracts revealed a major band and a minor band of SOD activity in the cells grown with manganese; however, cells grown with iron contained a single band of SOD activity with an R/sub f/ value similar to that of the major band found in cells grown with manganese. None of the SOD activity bands were abolished by the inclusion of 2 mM hydrogen peroxide in the SOD activity strain. S. mutans may not produce a separate iron-containing SOD but may insert either iron or manganese into an apo-SOD protein. Alternatively, iron may function in another activity (not SOD) that augments the defense against oxygen toxicity at low SOD levels. 28 references, 3 figures, 1 table.

  1. Retention of cadmium in cadmium-naive normal and iron-deficient rats as well as in cadmium-induced iron-deficient animals.

    PubMed

    Schäfer, S G; Schwegler, U; Schümann, K

    1990-08-01

    The retention of cadmium was investigated in cadmium-naive normal and iron-deficient rats in comparison to rats with cadmium-induced iron deficiency. Rats subchronically (4 weeks) exposed to dietary cadmium (28, 56, 112 ppm Cd and 28 ppm Fe) received a radioactively labeled dose of 2 mumol Cd/kg body wt; acutely (no cadmium exposure with diet) treated rats received doses between 1 and 8 mumol Cd/kg body wt. Two animals of each group received iron (1 mumol/kg as 59FeSO4 in order to monitor iron absorption in parallel. After a period of 4 weeks of feeding a cadmium-fortified diet, the test dose was administered and after a 2-weeks period 109Cd and of 59Fe retention was determined. The results showed in part an unexpected pattern of cadmium retention: subchronic feeding of cadmium induced iron deficiency. This implies an immediate interaction between the two metals with regard to intestinal transfer of iron. The retention of iron was increased in the Cd-induced anemia to the same extent as that in iron deficiency induced by iron restriction. Cadmium retention in iron deficiency induced by iron withdrawal also showed a marked increase, which implies that iron deficiency stimulates the intestinal transfer system for both metals in a similar way. Contrary to this effect, the cadmium retention in cadmium-induced iron deficiency was reduced to about 30% of control values. A self-induced aggravation of the body cadmium burden, as a consequence of the iron deficiency which is known to result from subchronic exposure to feeding of dietary cadmium, was thus excluded. PMID:2226245

  2. Manganese, nickel, selenium and cadmium in molluscs from the Magellan Strait, Chile.

    PubMed

    Astorga España, M S; Rodríguez Rodríguez, E M; Díaz Romero, C

    2004-08-01

    The concentrations of manganese, selenium, nickel and cadmium were determined in 112 samples of molluscs belonging to mussels (Mytilus chilensis, n = 47) and limpets (Nacella deaurata, n = 65), which were collected from the coastline of the Magellan Strait, Chile. Four (6.2%) samples of limpets exceeded the maximum limits for cadmium established in Europe. Limpets showed higher mean manganese, nickel and cadmium concentrations than mussels, whilst the mean selenium concentration in mussels was higher. The consumption of one serving (100 g) of molluscs represents a considerable contribution to the dietary daily intake of selenium, and limpets make a significant contribution to the manganese and cadmium intakes. The sampling zone influenced the trace element concentrations, and different uptakes were observed between the mollusc species. PMID:15370827

  3. Manganese- and iron-dependent marine methane oxidation.

    PubMed

    Beal, Emily J; House, Christopher H; Orphan, Victoria J

    2009-07-10

    Anaerobic methanotrophs help regulate Earth's climate and may have been an important part of the microbial ecosystem on the early Earth. The anaerobic oxidation of methane (AOM) is often thought of as a sulfate-dependent process, despite the fact that other electron acceptors are more energetically favorable. Here, we show that microorganisms from marine methane-seep sediment in the Eel River Basin in California are capable of using manganese (birnessite) and iron (ferrihydrite) to oxidize methane, revealing that marine AOM is coupled, either directly or indirectly, to a larger variety of oxidants than previously thought. Large amounts of manganese and iron are provided to oceans from rivers, indicating that manganese- and iron-dependent AOM have the potential to be globally important. PMID:19589998

  4. Manganese- and Iron-Dependent Marine Methane Oxidation

    NASA Astrophysics Data System (ADS)

    Beal, Emily J.; House, Christopher H.; Orphan, Victoria J.

    2009-07-01

    Anaerobic methanotrophs help regulate Earth’s climate and may have been an important part of the microbial ecosystem on the early Earth. The anaerobic oxidation of methane (AOM) is often thought of as a sulfate-dependent process, despite the fact that other electron acceptors are more energetically favorable. Here, we show that microorganisms from marine methane-seep sediment in the Eel River Basin in California are capable of using manganese (birnessite) and iron (ferrihydrite) to oxidize methane, revealing that marine AOM is coupled, either directly or indirectly, to a larger variety of oxidants than previously thought. Large amounts of manganese and iron are provided to oceans from rivers, indicating that manganese- and iron-dependent AOM have the potential to be globally important.

  5. Iron and Manganese in Potable Water

    E-print Network

    Young, Clifford Caudy

    1911-06-01

    be treated in a number of ways. It can be heated and con­ verted to M n 3 O4, or dissolved in hydrochloric acid and precipitated as Mn NH 4 P 0 4 . This last has been worked (Ril over by Gibbs 'and by Gooch and Austin , all of whom pronounce it very... of Manganese 2. The precipitation of Manganese by means of (RS) ammonium carbonate we can dismiss at once as not being 4. available for water, for calcium and magnesium would be precipitated at the same time. 3. The precipitation of Manganese as MnOa hy...

  6. Elements of the iron and manganese cycles in Lake Baikal

    USGS Publications Warehouse

    Granina, L.Z.; Callender, E.

    2007-01-01

    Using data obtained in recent years, we considered the external mass balance and characteristics of internal iron and manganese cycles in Lake Baikal (biological uptake, remineralization, sedimentary and diffusive fluxes, accumulation in sediments, time of renewal, etc.). Some previous results and common concepts were critically reevaluated. ?? Pleiades Publishing, Ltd. 2007.

  7. Iron and manganese are two similar ele-ments that can be a nuisance in a drinking

    E-print Network

    Iron and manganese are two similar ele- ments that can be a nuisance in a drinking water supply. Iron is more common than manganese, but they often occur together. They are not hazardous to health. What problems do iron and manganese cause? Iron and manganese can give water an unpleasant taste, odor

  8. Levels of cadmium, manganese and lead in water and algae; Spirogyra aequinoctialis

    Microsoft Academic Search

    C. C. Kaonga; S. S. Chiotha; E. Fabiano; E. M. Henry

    This study assessed the ability of filamentous green algae; Spirogyra aequinoctialis to accumulate manganese, cadmium and lead from water. Water pH was also determined. Samples of S. aequinoctialis and their respective water environments were taken from designated sampling points in the city of Blantyre and Malawi during the rainy and dry season in order to capture seasonal variations. The concentration

  9. Adsorption of selenium by amorphous iron oxyhydroxide and manganese dioxide

    USGS Publications Warehouse

    Balistrieri, L.S.; Chao, T.T.

    1990-01-01

    This work compares and models the adsorption of selenium and other anions on a neutral to alkaline surface (amorphous iron oxyhydroxide) and an acidic surface (manganese dioxide). Selenium adsorption on these oxides is examined as a function of pH, particle concentration, oxidation state, and competing anion concentration in order to assess how these factors might influence the mobility of selenium in the environment. The data indicate that 1. 1) amorphous iron oxyhydroxide has a greater affinity for selenium than manganese dioxide, 2. 2) selenite [Se(IV)] adsorption increases with decreasing pH and increasing particle concentration and is stronger than selenate [Se(VI)] adsorption on both oxides, and 3. 3) selenate does not adsorb on manganese dioxide. The relative affinity of selenate and selenite for the oxides and the lack of adsorption of selenate on a strongly acidic surface suggests that selenate forms outer-sphere complexes while selenite forms inner-sphere complexes with the surfaces. The data also indicate that the competition sequence of other anions with respect to selenite adsorption at pH 7.0 is phosphate > silicate > molybdate > fluoride > sulfate on amorphous iron oxyhydroxide and molybdate ??? phosphate > silicate > fluoride > sulfate on manganese dioxide. The adsorption of phosphate, molybdate, and silicate on these oxides as a function of pH indicates that the competition sequences reflect the relative affinities of these anions for the surfaces. The Triple Layer surface complexation model is used to provide a quantitative description of these observations and to assess the importance of surface site heterogeneity on anion adsorption. The modeling results suggest that selenite forms binuclear, innersphere complexes with amorphous iron oxyhydroxide and monodentate, inner-sphere complexes with manganese dioxide and that selenate forms outer-sphere, monodentate complexes with amorphous iron oxyhydroxide. The heterogeneity of the oxide surface sites is reflected in decreasing equilibrium constants for selenite with increasing adsorption density and both experimental observations and modeling results suggest that manganese dioxide has fewer sites of higher energy for selenite adsorption than amorphous iron oxyhydroxide. Modeling and interpreting the adsorption of phosphate, molybdate, and silicate on the oxides are made difficult by the lack of constraint in choosing surface species and the fact that equally good fits can be obtained with different surface species. Finally, predictions of anion competition using the model results from single adsorbate systems are not very successful because the model does not account for surface site heterogeneity. Selenite adsorption data from a multi-adsorbate system could be fit if the equilibrium constant for selenite is decreased with increasing anion adsorption density. ?? 1990.

  10. Manganese

    MedlinePLUS

    ... iron, zincTaking calcium along with any of these minerals can decrease the amount of manganese that the body can take in.IP-6 (Phytic acid)IP-6 found in foods, such as cereals, nuts, and beans, and in supplements can decrease the amount of ...

  11. Manganese (Mn) and Iron (Fe): Interdependency of Transport and Regulation

    Microsoft Academic Search

    Vanessa A. Fitsanakis; Na Zhang; Stephanie Garcia; Michael Aschner

    2010-01-01

    Manganese (Mn) and iron (Fe) are transition metals that are crucial to the appropriate growth, development, function, and\\u000a maintenance of biological organisms. Because of their chemical similarity, in organisms ranging from bacteria to mammals they\\u000a share and compete for many protein transporters, such as the divalent metal transporter-1. As such, during conditions of low\\u000a Fe, abnormal Mn accumulation occurs. Conversely,

  12. Catalysis of peroxynitrite reactions by manganese and iron porphyrins.

    PubMed

    Balavoine, G G; Geletti, Y V; Bejan, D

    1997-01-01

    Kinetics and products of peroxynitrite anion O=NOO- reactions, catalyzed by water-soluble manganese and iron porphyrins, were studied under basic and neutral conditions. In the absence of organic substrates peroxynitrite decomposes catalytically to give nitrite and dioxygen as major products. Catalytic decomposition competes with direct oxidation of sulfoxide to sulfone, while phenol is catalytically nitrated in o- and p-positions. A reaction mechanism is proposed. PMID:9466957

  13. Biogeochemistry of manganese- and iron-rich sediments in Toolik Lake, Alaska

    Microsoft Academic Search

    Jeffrey C. Cornwell; George W. Kipphut

    1992-01-01

    The sediments within Toolik Lake in arctic Alaska are characterized by extremely low rates of organic matter sedimentation\\u000a and unusually high concentrations of iron and manganese. Pore water and solid phase measurements of iron, manganese, trace\\u000a metals, carbon, nitrogen, phosphorus, and sulfur are consistent with the hypothesis that the reduction of organic matter by\\u000a iron and manganese is the most

  14. Iron and manganese oxide mineralization in the Pacific

    USGS Publications Warehouse

    Hein, J.R.; Koschinsky, A.; Halbach, P.; Manheim, F. T.; Bau, M.; Kang, J.-K.; Lubick, N.

    1997-01-01

    Iron, manganese, and iron-manganese deposits occur in nearly all geomorphologic and tectonic environments in the ocean basins and form by one or more of four processes: (1) hydrogenetic precipitation from cold ambient seawater, (2) precipitation from hydrothermal fluids, (3) precipitation from sediment pore waters that have been modified from bottom water compositions by diagenetic reactions in the sediment column and (4) replacement of rocks and sediment. Iron and manganese deposits occur in five forms: nodules, crusts, cements, mounds and sediment-hosted stratabound layers. Seafloor oxides show a wide range of compositions from nearly pure iron to nearly pure manganese end members. Fe/Mn ratios vary from about 24 000 (up to 58% elemental Fe) for hydrothermal seamount ironstones to about 0.001 (up to 52% Mn) for hydrothermal stratabound manganese oxides from active volcanic arcs. Hydrogenetic Fe-Mn crusts that occur on most seamounts in the ocean basins have a mean Fe/Mn ratio of 0.7 for open-ocean seamount crusts and 1.2 for continental margin seamount crusts. Fe-Mn nodules of potential economic interest from the Clarion-Clipperton Zone have a mean Fe/Mn ratio of 0.3, whereas the mean ratio for nodules from elsewhere in the Pacific is about 0.7. Crusts are enriched in Co, Ni and Pt and nodules in Cu and Ni, and both have significant concentrations of Pb, Zn, Ba, Mo, V and other elements. In contrast, hydrothermal deposits commonly contain only minor trace metal contents, although there are many exceptions, for example, with Ni contents up to 0.66%, Cr to 1.2%, and Zn to 1.4%. Chondrite-normalized REE patterns generally show a positive Ce anomaly and abundant ??REEs for hydrogenetic and mixed hydrogenetic-diagenetic deposits, whereas the Ce anomaly is negative for hydrothermal deposits and ??REE contents are low. However, the Ce anomaly in crusts may vary from strongly positive in East Pacific crusts to slightly negative in West Pacific crusts, which may reflect the redox conditions of seawater. The concentration of elements in hydrogenetic Fe-Mn crusts depends on a wide variety of water column and crust surface characteristics, whereas concentration of elements in hydrothermal oxide deposits depends of the intensity of leaching, rock types leached, and precipitation of sulphides at depth in the hydrothermal system.

  15. Zinc, iron, manganese, and magnesium accumulation in crayfish populations near copper-nickel smelters at Sudbury, Ontario, Canada

    SciTech Connect

    Bagatto, G.; Alikhan, M.A.

    1987-06-01

    The Sudbury basin has been subjected to extreme ecological disturbances from logging, mining and smelting activities. Elevated concentrations of copper, cadmium, and nickel have been reported in crayfish populations close to the Sudbury smelting works. The present study compares concentrations of zinc (Zn), iron (Fe), manganese (Mn) and magnesium (Mg) in freshwater crayfish at selected distances of the habitat from the emission source. These metals were selected since they are known to be emitted in moderately high quantities into the Sudbury environment as byproduct of the smelting process. Various tissue concentrations in crayfish were also examined to determined specific tissue sites for these accumulations.

  16. THE ACCUMULATION AND DISTRIBUTION OF VANADIUM, IRON, AND MANGANESE IN SOME SOLITARY ASCIDIANS

    Microsoft Academic Search

    H. MICHIBATA; T. TERADA; N. ANADA; K. YAMAKAWA; T. NUMAKUNAI

    The vanadium, iron, and manganese contents of 15 species of solitary ascidians belonging to the suborders Phlebobranchia and Stolidobranchia were determined by thermal neutron activation analysis. Vanadium was detectable in all species exam med. In general, the vanadium content in various tissues ofthe Phlebobranchia was considerably higher than the iron and manganese contents. The blood cells especially contained a large

  17. Iron-manganese nodules from nares abyssal plain: geochemistry and mineralogy.

    PubMed

    Smith, R E; Gassaway, J D; Giles, H N

    1968-08-23

    Three nodules from a core taken north of Puerto Rico are composed chiefly of an x-ray amorphous, hydrated, iron-manganese oxide, with secondary goethite, and minor detrital silicates incorporated during growth of the nodules. No primary manganese mineral is apparent. The nodules are enriched in iron and depleted in manganese relative to Atlantic Ocean averages. The formation of these nodules appears to have been contemporary with sedimentation and related to volcanic activity. PMID:17802621

  18. Growth and characterization of gel grown pure and mixed iron-manganese levo-tartrate crystals

    Microsoft Academic Search

    S. J. Joshi; B. B. Parekh; K. D. Vohra; M. J. Joshi

    2006-01-01

    Several applications of iron tartrate and manganese tartrate compounds are reported in the literature. In the present investigation,\\u000a we have grown pure and mixed iron (II)-manganese levo-tartrate crystals by single diffusion gel growth technique. Crystals\\u000a with spherulitic morphology were harvested. The colouration of the crystals changed from black to pinkish brown upon increasing\\u000a the content of manganese in the crystals.

  19. The mechanism of cadmium surface complexation on iron oxyhydroxide minerals

    NASA Astrophysics Data System (ADS)

    Randall, S. R.; Sherman, D. M.; Ragnarsdottir, K. V.; Collins, Clare R.

    1999-10-01

    Many sediment and soil systems have become significantly contaminated with cadmium, and earth scientists are now required to make increasingly accurate predictions of the risks that this contamination poses. This necessitates an improved understanding of the processes that control the mobility and bioavailability of cadmium in the environment. With this in mind, we have studied the composition and structure of aqueous cadmium sorption complexes on the iron oxyhydroxide minerals goethite (?-FeOOH), lepidocrocite (?-FeOOH), akaganeite (?-FeOOH), and schwertmannite (Fe8O8(OH)6SO4) using extended X-ray adsorption fine structure spectroscopy. The results show that adsorption to all of the studied minerals occurs via inner sphere adsorption over a wide range of pH and cadmium concentrations. The bonding mechanism varies between minerals and appears to be governed by the availability of different types of adsorption site at the mineral surface. The geometry and relative stability of cadmium adsorption complexes on the goethite surface was predicted with ab initio quantum mechanical modelling. The modelling results, used in combination with the extended X-ray adsorption fine structure data, allow an unambiguous determination of the mechanism by which cadmium bonds to goethite. Cadmium adsorbs to goethite by the formation of bidentate surface complexes at corner sharing sites on the predominant (110) crystallographic surface. There is no evidence for significant cadmium adsorption to goethite at the supposedly more reactive edge sharing sites. This is probably because the edge sharing sites are only available on the (021) crystallographic surface, which comprises just ?2% of the total mineral surface area. Conversely, cadmium adsorption on lepidocrocite occurs predominately by the formation of surface complexes at bi- and/or tridentate edge sharing sites. We explain the difference in extended X-ray adsorption fine structure results for cadmium adsorption on goethite and lepidocrocite by the greater availability of reactive edge sharing sites on lepidocrocite than on goethite. The structures of cadmium adsorption complexes on goethite and lepidocrocite appear to be unaffected by changes in pH and surface loading. There is no support for cadmium sorption to any of the studied minerals via the formation of an ordered precipitate, even at high pH and high cadmium concentration. Cadmium adsorption on akaganeite and schwertmannite also occurs via inner sphere bonding, but the mechanism(s) by which this occurs remains ambiguous.

  20. Atmospheric input of manganese and iron to the ocean: Seawater dissolution experiments with Saharan and North American dusts

    E-print Network

    Guieu, Cécile

    Atmospheric input of manganese and iron to the ocean: Seawater dissolution experiments with Saharan online 9 September 2008 Keywords: Iron Manganese Aerosol Dust dissolution Marine chemistry Dissolution of wind blown dust is a major source of iron, manganese and other trace nutrients in the ocean. Kinetic

  1. Manganese Doping of Magnetic Iron Oxide Nanoparticles: Tailoring Surface Reactivity for a Regenerable Heavy Metal Sorbent

    SciTech Connect

    Warner, Cynthia L.; Chouyyok, Wilaiwan; Mackie, Katherine E.; Neiner, Doinita; Saraf, Laxmikant; Droubay, Timothy C.; Warner, Marvin G.; Addleman, Raymond S.

    2012-02-28

    A method for tuning the analyte affinity of magnetic, inorganic nanostructured sorbents for heavy metal contaminants is described. The manganese-doped iron oxide nanoparticle sorbents have a remarkably high affinity compared to the precursor material. Sorbent affinity can be tuned toward an analyte of interest simply by adjustment of the dopant quantity. The results show that following the Mn doping process there is a large increase in affinity and capacity for heavy metals (i.e., Co, Ni, Zn, As, Ag, Cd, Hg, and Tl). Capacity measurements were carried out for the removal of cadmium from river water and showed significantly higher loading than the relevant commercial sorbents tested for comparison. The reduction in Cd concentration from 100 ppb spiked river water to 1 ppb (less than the EPA drinking water limit of 5 ppb for Cd) was achieved following treatment with the Mn-doped iron oxide nanoparticles. The Mn-doped iron oxide nanoparticles were able to load 1 ppm of Cd followed by complete stripping and recovery of the Cd with a mild acid wash. The Cd loading and stripping is shown to be consistent through multiple cycles with no loss of sorbent performance.

  2. Distribution of Manganese, Nickel, Zinc, Cadmium, and Arsenic in sediments and in the standard elutriate

    Microsoft Academic Search

    J. M. Brannon; R. M. Engler; J. R. Rose; P. G. Hunt; I. Smith

    1976-01-01

    Sequential, selective chemical extraction was used to separate estuarine (Mobile Bay, Alabama), freshwater (Ashtabula, Ohio), and marine (Bridgeport, Connecticut) sediments into fractions (1) dissolved in sediment interstitial water; (2) adsorbed on mineral surfaces; (3) associated with hydrous iron and manganese oxides and hydroxides; (4) associated with sediment organic matter and sulfides; and (5) bound within the lattice of crystalline minerals

  3. Distributions of Manganese, Iron, and Manganese-Oxidizing Bacteria In Lake Superior Sediments of Different Organic Carbon Content

    NASA Technical Reports Server (NTRS)

    Richardson, Laurie L.; Nealson, Kenneth H.

    1989-01-01

    Profiles of oxygen, soluble and particulate manganese and iron, organic carbon and nitrogen were examined in Lake Superior sediment cores, along with the distribution and abundance of heterotrophic and manganese oxidizing bacteria. Analyses were performed using cores collected with the submersible Johnson Sea Link II. Three cores, exhibiting a range of organic carbon content, were collected from the deepest basin in Lake Superior and the north and south ends of the Caribou trough, and brought to the surface for immediate analysis. Minielectrode profiles of oxygen concentration of the three cores were carried out using a commercially available minielectrode apparatus. Oxygen depletion to less than 1% occurred within 4 cm of the surface for two of the cores, but not until approximately 15 cm for the core from the south basin of the Caribou trough. The three cores exhibited very different profiles of soluble, as well as leachable, manganese and iron, suggesting different degrees of remobilization of these metals in the sediments. Vertical profiles of viable bacteria and Mn oxidizing bacteria, determined by plating and counting, showed that aerobic (and facultatively aerobic) heterotrophic bacteria were present at the highest concentrations near the surface and decreased steadily with depth, while Mn oxidizing bacteria were concentrations primarily at and above the oxic/anoxic interface. Soluble manganese in the pore waters, along with abundant organic carbon, appeared to enhance the presence of manganese oxidizing bacteria, even below the oxic/anoxic interface. Profiles of solid-phase leachable manganese suggested a microbial role in manganese reprecipitation in these sediments.

  4. [Ecological stability on biological removal of iron and manganese filter under poor nutritional conditions].

    PubMed

    Yang, Hong; Xiong, Xiao-Li; Duan, Xiao-Dong; Song, Li-Xin; Yu, Ping-Bo; Li, Wei; Zhang, Jie

    2010-01-01

    To supply necessary bacteria and available nutrients, a method of returning backwashing wastewater to the bio-filter for removal of iron and manganese was used. The ecological stability of bio-filter was investigated from 3 aspects: iron and manganese removal efficiency, micro-ecological characteristics and the quantity distribution of dominant bacteria. The results indicated that, the bio-filter held strong antishock loading capability, when the system was operated at high filtration rate (10-13.9 m/h) and high manganese concentration (3.5-4.5 mg/L), a removal rate more than 98.9% of iron and manganese was achieved. Iron and manganese oxidizing bacteria are the dominant microflora in biological filtering layer, they not only adhere on filter sand materials (4.3 x 10(6) MPN/mL) to form compact biofilm, but also exist among filter materials void (6.5 x 10(6) MPN/mL) to form suspended flocs, which is very important to complete removal of iron and manganese. In the past 5 years, the bio-filter realized a continuous and stable operation and kept a high removal efficiency of iron and manganese without adding any nutrients. PMID:20329523

  5. Voltammetric determination of arsenic in high iron and manganese groundwaters.

    PubMed

    Gibbon-Walsh, Kristoff; Salaün, Pascal; Uroic, M Kalle; Feldmann, Joerg; McArthur, John M; van den Berg, Constant M G

    2011-09-15

    Determination of the speciation of arsenic in groundwaters, using cathodic stripping voltammetry (CSV), is severely hampered by high levels of iron and manganese. Experiments showed that the interference is eliminated by addition of EDTA, making it possible to determine the arsenic speciation on-site by CSV. This work presents the CSV method to determine As(III) in high-iron or -manganese groundwaters in the field with only minor sample treatment. The method was field-tested in West-Bengal (India) on a series of groundwater samples. Total arsenic was subsequently determined after acidification to pH 1 by anodic stripping voltammetry (ASV). Comparative measurements by ICP-MS as reference method for total As, and by HPLC for its speciation, were used to corroborate the field data in stored samples. Most of the arsenic (78±0.02%) was found to occur as inorganic As(III) in the freshly collected waters, in accordance with previous studies. The data shows that the modified on-site CSV method for As(III) is a good measure of water contamination with As. The EDTA was also found to be effective in stabilising the arsenic speciation for longterm sample storage at room temperature. Without sample preservation, in water exposed to air and sunlight, the As(III) was found to become oxidised to As(V), and Fe(II) oxidised to Fe(III), removing the As(V) by adsorption on precipitating Fe(III)-hydroxides within a few hours. PMID:21807202

  6. Evaluation of the effect of divalent metal transporter 1 gene polymorphism on blood iron, lead and cadmium levels.

    PubMed

    Kayaalt?, Zeliha; Akyüzlü, Dilek Kaya; Söylemezo?lu, Tülin

    2015-02-01

    Divalent metal transporter 1 (DMT1), a member of the proton-coupled metal ion transporter family, mediates transport of ferrous iron from the lumen of the intestine into the enterocyte and export of iron from endocytic vesicles. It has an affinity not only for iron but also for other divalent cations including manganese, cobalt, nickel, cadmium, lead, copper, and zinc. DMT1 is encoded by the SLC11a2 gene that is located on chromosome 12q13 in humans and express four major mammalian isoforms (1A/+IRE, 1A/-IRE, 2/+IRE and 2/-IRE). Mutations or polymorphisms of DMT1 gene may have an impact on human health by disturbing metal trafficking. To study the possible association of DMT1 gene with the blood levels of some divalent cations such as iron, lead and cadmium, a single nucleotide polymorphism (SNP) (IVS4+44C/A) in DMT1 gene was investigated in 486 unrelated and healthy individuals in a Turkish population by method of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The genotype frequencies were found as 49.8% homozygote typical (CC), 38.3% heterozygote (CA) and 11.9% homozygote atypical (AA). Metal levels were analyzed by dual atomic absorption spectrometer system and the average levels of iron, lead and cadmium in the blood samples were 446.01±81.87ppm, 35.59±17.72ppb and 1.25±0.87ppb, respectively. Individuals with the CC genotype had higher blood iron, lead and cadmium levels than those with AA and CA genotypes. Highly statistically significant associations were detected between IVS4+44 C/A polymorphism in the DMT1 gene and iron and lead levels (p=0.001 and p=0.036, respectively), but no association was found with cadmium level (p=0.344). This study suggested that DMT1 IVS4+44 C/A polymorphism is associated with inter-individual variations in blood iron, lead and cadmium levels. PMID:25483413

  7. Influences on the oceanic biogeochemical cycling of the hybrid-type metals, cobalt, iron, and manganese

    E-print Network

    Noble, Abigail Emery

    2012-01-01

    Trace metal cycling is one of many processes that influence ocean ecosystem dynamics. Cobalt, iron, and manganese are redox active trace metal micro-nutrients with oceanic distributions that are influenced by both biological ...

  8. Kinetics of Ion Removal from an Iron-Rich Industrial Coproduct: III. Manganese and Chromium

    E-print Network

    Sparks, Donald L.

    Kinetics of Ion Removal from an Iron-Rich Industrial Coproduct: III. Manganese and Chromium Yigal pollutants of soil and water. Chromium (VI) can be toxic to mammals, and the hazard of Cr3+ is its potential

  9. Environmentally acquired lead, cadmium, and manganese in the cattle egret, Bubulcus ibis , and the laughing gull, Larus atricilla

    Microsoft Academic Search

    Michael Hulse; John S. Mahoney; Gene D. Schroder; Carl S. Hacker; Stanley M. Pier

    1980-01-01

    The concentrations of lead, cadmium, and manganese in the tissues of cattle egrets (Bubulcus ibis) and laughing gulls (Larus atricilla) gathered from the Galveston Bay region of Texas were compared, to determine if different patterns of accumulation exist. Their levels in these species were within the range reported for other bird species. Lead levels in bone were comparable, but gulls

  10. Determination of Urinary Trace Elements (Arsenic, Copper, Cadmium, Manganese, Lead, Zinc, Selenium) in Patients with Blackfoot Disease

    Microsoft Academic Search

    Jin-Lian Tsai; Pin-Hua Horng; Tzung-Jeng Hwang; John W. Hsu; Ching-Jyi Horng

    2004-01-01

    To determine the relationship of arsenic, copper, cadmium, manganese, lead, zinc and selenium to Blackfoot disease (BFD, a peripheral vascular disorder endemic to areas of Taiwan, which has been linked to arsenic in drinking water) the authors measured the amount of these substances in urine from BFD patients, using atomic absorption spectrometry. Results indicate significantly higher amounts of urinary arsenic,

  11. Hawaiian submarine manganese-iron oxide crusts - A dating tool?

    USGS Publications Warehouse

    Moore, J.G.; Clague, D.A.

    2004-01-01

    Black manganese-iron oxide crusts form on most exposed rock on the ocean floor. Such crusts are well developed on the steep lava slopes of the Hawaiian Ridge and have been sampled during dredging and submersible dives. The crusts also occur on fragments detached from bedrock by mass wasting, on submerged coral reefs, and on poorly lithified sedimentary rocks. The thickness of the crusts was measured on samples collected since 1965 on the Hawaiian Ridge from 140 dive or dredge localities. Fifty-nine (42%) of the sites were collected in 2001 by remotely operated vehicles (ROVs). The thinner crusts on many samples apparently result from post-depositional breakage, landsliding, and intermittent burial of outcrops by sediment. The maximum crust thickness was selected from each dredge or dive site to best represent crusts on the original rock surface at that site. The measurements show an irregular progressive thickening of the crusts toward the northwest-i.e., progressive thickening toward the older volcanic features with increasing distance from the Hawaiian hotspot. Comparison of the maximum crust thickness with radiometric ages of related subaerial features supports previous studies that indicate a crust-growth rate of about 2.5 mm/m.y. The thickness information not only allows a comparison of the relative exposure ages of two or more features offshore from different volcanoes, but also provides specific age estimates of volcanic and landslide deposits. The data indicate that some of the landslide blocks within the south Kona landslide are the oldest exposed rock on Mauna Loa, Kilauea, or Loihi volcanoes. Crusts on the floors of submarine canyons off Kohala and East Molokai volcanoes indicate that these canyons are no longer serving as channelways for downslope, sediment-laden currents. Mahukona volcano was approximately synchronous with Hilo Ridge, both being younger than Hana Ridge. The Nuuanu landslide is considerably older than the Wailau landslide. The Waianae landslide southwest of Oahu has yielded samples with the greatest manganese-iron oxide crusts (9.5 mm thick) and therefore apparently represents the oldest submarine material yet found in the study area. The submarine volcanic field 100 km southwest of Oahu is apparently younger than the Waianae landslide. ?? 2004 Geological Society of America.

  12. Morphology of graphite-supported iron-manganese catalyst particles: Formation of hollow spheres during oxidation

    SciTech Connect

    Chen, A.A.; Vannice, M.A.; Phillips, J. (Pennsylvania State Univ., University Park (USA))

    1989-04-01

    Transmission electron microscopy (TEM) and Moessbauer spectroscopy (MES) were used to study the morphology of graphite-supported iron-manganese particles. Following oxidation at 500 K MES showed the iron in the particles to be fully oxidized. TEM showed all the particles to be torroidal in appearance. However, tilting resulting in no change in the apparent dimensions of the particles, yet the apparent distances between particles were sharply reduced. These results suggest the particles are actually spherical. On the basis of these experiments, and similar experiments with reduced particles, a model was developed: Following reduction the particles are spherical and consist of a metallic iron core surrounded by a shell of manganese oxide. During oxidation, iron ions diffuse through the manganese oxide shell to the particle surface. Eventually, this results in the formation of nearly spherical particles with hollow centers, inner shells of iron-manganese spinel, and outer shells of iron oxide. Upon an additional reduction the hollow center remains, but the shells phase segregate into regions of iron metal and manganese oxide.

  13. Removal of iron and manganese from micro-polluted surface source water using bio-sand filtration system

    Microsoft Academic Search

    Si-min Li; Bo Zhao; Zhennan Shi; Wei Zhang

    2010-01-01

    Bio-sand filter was adopted to study the iron and manganese removal from micro-polluted surface source water, and the effect by biofilm formation method, dissolved oxygen (DO) and water temperature on iron and manganese were analyzed. The results demonstrate that natural start-up and inoculm start-up methods of filters both have a high removal of iron and manganese. The former method is

  14. The influence of high iron diet on rat lung manganese absorption

    SciTech Connect

    Thompson, Khristy [Department of Genetics and Complex Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115 (United States); Molina, Ramon [Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115 (United States); Donaghey, Thomas [Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115 (United States); Brain, Joseph D. [Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115 (United States); Wessling-Resnick, Marianne [Department of Genetics and Complex Diseases, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115 (United States)]. E-mail: wessling@hsph.harvard.edu

    2006-01-15

    Individuals chronically exposed to manganese are at high risk for neurotoxic effects of this metal. A primary route of exposure is through respiration, although little is known about pulmonary uptake of metals or factors that modify this process. High dietary iron levels inversely affect intestinal uptake of manganese, and a major goal of this study was to determine if dietary iron loading could increase lung non-heme iron levels and alter manganese absorption. Rats were fed a high iron (1% carbonyl iron) or control diet for 4 weeks. Lung non-heme iron levels increased {approx}2-fold in rats fed the high iron diet. To determine if iron-loading affected manganese uptake, {sup 54}Mn was administered by intratracheal (it) instillation or intravenous (iv) injection for pharmacokinetic studies. {sup 54}Mn absorption from the lungs to the blood was lower in it-instilled rats fed the 1% carbonyl iron diet. Pharmacokinetics of iv-injected {sup 54}Mn revealed that the isotope was cleared more rapidly from the blood of iron-loaded rats. In situ analysis of divalent metal transporter-1 (DMT1) expression in lung detected mRNA in airway epithelium and bronchus-associated lymphatic tissue (BALT). Staining of the latter was significantly reduced in rats fed the high iron diet. In situ analysis of transferrin receptor (TfR) mRNA showed staining in BALT alone. These data demonstrate that manganese absorption from the lungs to the blood can be modified by iron status and the route of administration.

  15. Iron, Manganese and Copper Release from Synthetic Hydroxyapatite

    NASA Technical Reports Server (NTRS)

    Sutter, B.; Hossner, L. R.; Ming, Douglas W.

    1999-01-01

    Kinetic stir-flow dissolution experiments were performed on iron- (Fe-SHA), manganese- (Mn-SHA), and copper- (Cu-SHA) containing synthetic hydroxyapatites. Solution treatments consisted of de-ionized water, citric acid and DTPA. Initially, Mn concentrations were higher than Cu concentrations and Fe concentrations were the lowest in all treatments. At later times Mn and Cu concentrations dropped in the DTPA treatment while Fe rose to the concentration similar to Mn and Cu. At all times, metal release concentrations in the water and citric acid treatments followed the trend of Mn>Cu>Fe. Rietveld analysis of x-ray diffraction data and ^31P NMR indicated that the metals substituted for Ca in the SHA structure. However, EPR data suggested that a metal (hydr)oxide phase existed either on the SHA surface or between the SHA crystallites. The metal concentration trend of Mn>Cu>Fe suggested that the initial solution metal concentrations are dependent on the dissolution of (hydr)oxides from SHA surfaces or between SHA crystallites. Similar metal concentrations at later times in the DTPA experiments suggests that metal concentrations were controlled by the release of Mn, Cu, or Fe from the SHA structure.

  16. An optically-interrogated microwave-Poynting-vector sensor using cadmium manganese telluride.

    PubMed

    Chen, Chia-Chu; Whitaker, John F

    2010-06-01

    A single <110> cadmium-manganese-telluride crystal that exhibits both the Pockels and Faraday effects is used to produce a Poynting-vector sensor for signals in the microwave regime. This multi-birefringent crystal can independently measure either electric or magnetic fields through control of the polarization of the optical probe beam. After obtaining all the relevant electric and magnetic field components, a map of the Poynting vector along a 50-Omega microstrip was experimentally determined without the need for any further transformational calculations. The results demonstrate that this sensor can be used for near-field mapping of the Poynting vector. Utilizing both amplitude and phase information from the fields in the microwave signal, it was confirmed for the case of an open-terminated microstrip that no energy flowed to the load, while for a microstrip with a matched termination, the energy flowed consistently along the transmission line. PMID:20588348

  17. Cadmium-induced aggregation of iron regulatory protein-1.

    PubMed

    Liu, Ying; Xiao, Weiqun; Templeton, Douglas M

    2014-10-01

    Iron regulatory protein-1 (IRP-1) is central to regulation of iron homeostasis, and has been shown to be sensitive to Cd(2+) in vitro. Although Cd(2+) induces disulfide-bond formation in many proteins, the critical cysteine residues for iron binding in IRP-1 were shown not to be involved in Cd-induced IRP-1 aggregation in vitro. Here we show that Cd(2+) causes polymerization and aggregation of IRP-1 in vitro and in vivo, and decreases in a dose-dependent manner both its RNA-binding and aconitase enzymatic activities, as well as its cytosolic expression. We have used two-dimensional electrophoresis to demonstrate thiol-dependent self-association of purified recombinant IRP-1 treated with Cd(2+), as well as self-association in Cd(2+)-exposed mesangial cells. Circular dichroism spectra confirm significant conformational changes in the purified protein upon Cd(2+) exposure. Following Cd(2+) treatment, there is increased translocation of inactive IRP-1 to the actin cytoskeletal fraction, and this translocation is diminished by both antioxidant (BHA) treatment and inhibition of CaMK-II. These changes differ from those elicited by manipulation of iron levels. Cadmium-induced translocation of proteins to cellular compartments, and particularly to the cytoskeleton, is becoming a recognized event in Cd(2+) toxicity. Polymer-dependent translocation of IRP-1 in Cd(2+)-exposed cells may underlie effects of Cd(2+) on iron homeostasis. PMID:25106854

  18. Simultaneous determination of iron and manganese in water using artificial neural network catalytic spectrophotometric method

    NASA Astrophysics Data System (ADS)

    Ji, Hongwei; Xu, Yan; Li, Shuang; Xin, Huizhen; Cao, Hengxia

    2012-09-01

    A new analytical method using Back-Propagation (BP) artificial neural network and kinetic spectrophotometry for simultaneous determination of iron and magnesium in tap water, the Yellow River water and seawater is established. By conditional experiments, the optimum analytical conditions and parameters are obtained. Levenberg-Marquart (L-M) algorithm is used for calculation in BP neural network. The topological structure of three-layer BP ANN network architecture is chosen as 15-16-2 (nodes). The initial value of gradient coefficient µ is fixed at 0.001 and the increase factor and reduction factor of µ take the default values of the system. The data are processed by computers with our own programs written in MATLAB 7.0. The relative standard deviation of the calculated results for iron and manganese is 2.30% and 2.67% respectively. The results of standard addition method show that for the tap water, the recoveries of iron and manganese are in the ranges of 98.0%-104.3% and 96.5%-104.5%, and the RSD is in the range of 0.23%-0.98%; for the Yellow River water (Lijin district of Shandong Province), the recoveries of iron and manganese are in the ranges of 96.0%-101.0% and 98.7%-104.2%, and the RSD is in the range of 0.13%-2.52%; for the seawater in Qingdao offshore, the recoveries of iron and manganese are in the ranges of 95.3%-104.8% and 95.3%-104.7%, and the RSD is in the range of 0.14%-2.66%. It is found that 21 common cations and anions do not interfere with the determination of iron and manganese under the optimum experimental conditions. This method exhibits good reproducibility and high accuracy in the determination of iron and manganese and can be used for the simultaneous determination of iron and manganese in tap water and natural water. By using the established ANN-catalytic spectrophotometric method, the iron and manganese concentrations of the surface seawater at 11 sites in Qingdao offshore are determined and the level distribution maps of iron and manganese are drawn.

  19. Iron deficiency increases blood concentrations of neurotoxic metals in children.

    PubMed

    Kim, Yangho; Park, Sangkyu

    2014-08-01

    Iron deficiency affects approximately one-third of the world's population, occurring most frequently in children aged 6 months to 3 years. Mechanisms of iron absorption are similar to those of other divalent metals, particularly manganese, lead, and cadmium, and a diet deficient in iron can lead to excess absorption of manganese, lead, and cadmium. Iron deficiency may lead to cognitive impairments resulting from the deficiency itself or from increased metal concentrations caused by the deficiency. Iron deficiency combined with increased manganese or lead concentrations may further affect neurodevelopment. We recently showed that blood manganese and lead concentrations are elevated among iron-deficient infants. Increased blood manganese and lead levels are likely associated with prolonged breast-feeding, which is also a risk factor for iron deficiency. Thus, babies who are breast-fed for prolonged periods should be given plain, iron-fortified cereals or other good sources of dietary iron. PMID:25210521

  20. Effects of iron and manganese on the growth of rice and on the contents of these elements in rice

    E-print Network

    Boyer, Edmond

    Effects of iron and manganese on the growth of rice and on the contents of these elements in rice ppm Fe. . Manganese concentration in leaves and stems increased with increase in Mn levels and manganese in soils and plants has been conducted for many years. Many con- flicting results have been

  1. Multiple inorganic toxic substances contaminating the groundwater of Myingyan Township, Myanmar: Arsenic, manganese, fluoride, iron, and uranium.

    PubMed

    Bacquart, Thomas; Frisbie, Seth; Mitchell, Erika; Grigg, Laurie; Cole, Christopher; Small, Colleen; Sarkar, Bibudhendra

    2015-06-01

    In South Asia, the technological and societal shift from drinking surface water to groundwater has resulted in a great reduction of acute diseases due to water borne pathogens. However, arsenic and other naturally occurring inorganic toxic substances present in groundwater in the region have been linked to a variety of chronic diseases, including cancers, heart disease, and neurological problems. Due to the highly specific symptoms of chronic arsenic poisoning, arsenic was the first inorganic toxic substance to be noticed at unsafe levels in the groundwater of West Bengal, India and Bangladesh. Subsequently, other inorganic toxic substances, including manganese, uranium, and fluoride have been found at unsafe levels in groundwater in South Asia. While numerous drinking water wells throughout Myanmar have been tested for arsenic, relatively little is known about the concentrations of other inorganic toxic substances in Myanmar groundwater. In this study, we analyzed samples from 18 drinking water wells (12 in Myingyan City and 6 in nearby Tha Pyay Thar Village) and 2 locations in the Ayeyarwaddy River for arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. Concentrations of arsenic, manganese, fluoride, iron, or uranium exceeded health-based reference values in most wells. In addition, any given well usually contained more than one toxic substance at unsafe concentrations. While water testing and well sharing could reduce health risks, none of the wells sampled provide water that is entirely safe with respect to inorganic toxic substances. It is imperative that users of these wells, and users of other wells that have not been tested for multiple inorganic toxic substances throughout the region, be informed of the need for drinking water testing and the health consequences of drinking water contaminated with inorganic toxic substances. PMID:25748724

  2. Manganese-mitigation of cadmium toxicity to seedling growth of Phytolacca acinosa Roxb. is controlled by the manganese/cadmium molar ratio under hydroponic conditions.

    PubMed

    Liu, Huimin; Zhang, Yuxiu; Chai, Tuanyao; Tan, Jinjuan; Wang, Jianwu; Feng, Shanshan; Liu, Geyu

    2013-12-01

    Manganese (Mn) can interact with cadmium (Cd) in environments and influence the toxic effect of Cd on plants. However, few studies have investigated the relationship between the Mn/Cd ratio and plant Cd-toxicity along Cd concentrations. In this paper, we studied the effects of external Mn/Cd molar ratios (0, 10, 30, 50 and 60) on Cd toxicity in the Mn hyperaccumulator and Cd tolerant plant, Phytolacca acinosa Roxb., at three Cd levels (50, 100 and 200 ?M) under hydroponic conditions. Our result showed that seedling growth (y) under Cd stress was strongly positively related to the solution Mn/Cd molar ratio (SMCR). The relationship between the two variables under solution Cd concentrations was well explained by the linear regression model y=a+b1 (SMCR)+b2 (Solution-Cd). Increasing SMCR significantly reduced the Cd concentration and increased the Mn concentration in plant tissues. However, seedling growth was consistent with the shoot Mn/Cd molar ratio rather than with the Mn or Cd concentrations in plant tissues. At low levels of SMCR (e.g. 0 and 10), elevation of Mn distribution in shoot tissues might be a mechanism in P. acinosa seedlings to defend against Cd-toxicity. In comparison with low levels of SMCR, high levels of SMCR (e.g. 50 and 60) greatly alleviated lipid peroxidation and plant water-loss, and enhanced photosynthesis. However, the alleviated lipid peroxidation in the Mn-mitigation of Cd toxicity was likely to be the secondary effect resulting from the antagonism between Mn and Cd in the plant. PMID:24095921

  3. PLANT UPTAKE OF CADMIUM, ZINC, AND MANGANESE FROM FOUR CONTRASTING SOILS AMENDED WITH Cd-ENRICHED SEWAGE SLUDGE

    Microsoft Academic Search

    V. Ramachandran; T. J. DSouza

    2002-01-01

    Studies on the uptake of cadmium, zinc and manganese from Cd-enriched sewage sludge (0–80 mg Cd kg) amended Ultisol, Alfisol, Entisol and Vertisol by maize (Zea mays L.) followed by mung bean (Phaseolus aureus Roxb.) revealed that in general, there was a progressive reduction in the dry matter yield of both the crops due to enhanced Cd concentrations in the soil-sludge mixture in

  4. Role of iron in jejunal uptake of cadmium in the newborn rat

    SciTech Connect

    Leon, L.; Johnson, D.R.

    1985-01-01

    There is evidence that suckling animals and children have a greater capacity for intestinal transport of both essential and nonessential metals than do adults of the species. It has also been observed in experiments using adult animals that the intestinal transport of iron and the nonessential metal cadmium interact with one another. In the study reported here, the influence of tissue iron status on jejunal uptake of cadmium was investigated in suckling, adolescent, and young adult rats using an in situ incubation technique. In the presence of 0.4 mM FeSO/sub 4/, intestinal uptake of cadmium was significantly decreased in 14-d-old pups. Access to an iron-deficient diet reduced tissue iron levels in 28- and 42-d-old but not in 14-d-old rats. Intestinal uptake of cadmium was significantly greater in 28- and 42-d-old rats placed on the iron-deficient diet but did not change in 14-d-old rats compared to controls. In suckling rats injected with iron dextran over a six-d period, a significant decrease in intestinal uptake of both cadmium and iron was observed compared to controls. The results of the present study suggest that intestinal cadmium transport in the suckling, as well as the adolescent and young adult rat, interacts with, at least in part, the pathway responsible for iron transport.

  5. Induction of superoxide dismutases in Escherichia coli by manganese and iron

    Microsoft Academic Search

    S. Y. R. Pugh; J. L. DiGuiseppi; I. Fridovich

    1984-01-01

    Growth of Escherichia coli B in simple media enriched with Mn(II) resulted in the elevation of the manganese-containing superoxide dismutase, whereas growth in such medium enriched with iron caused increased content of the iron-containing superoxide dismutase. Enrichment of the medium with Co(II), Cu(II), Mo(VI), Zn(II), or Ni(II) had no effect. The inductions of superoxide dismutase by Mn(II) or by Fe(II)

  6. Geological reconnaissance of some Uruguayan iron and manganese deposits in 1962

    USGS Publications Warehouse

    Wallace, Roberts Manning

    1976-01-01

    Three mineralized areas lie in an area near the town of Minas de Corrales in the Departamento de Rivera; they are the Cerro Amelia, the Cerro de Papagayo, and the Cerro Iman. The Cerro Amelia is composed of small bands of iron-rich rock separated by an amphibolitic or mafic rock. Selective mining would be necessary to extract the 31,000 tons per meter of depth of iron-rich rock that ranges from 15 to 40 percent metallic iron. The Cerro de Papagayo district contains many small, rich deposits of ferruginous manganese ore. The ratio of Mn to Fe varies widely within each small deposit as well as from deposit to deposit. Some ferruginous manganese ore contains 50-55 percent manganese dioxide. Although there are many thousands of tons of ore in the district, small-scale mining operations are imperative. One deposit, the Cerro Avestuz manganese mine, was visited. The manganese ore body lies within contorted highly metamorphosed itabirite that contains both hard low grade and soft high grade ferruginous manganese ores estimated to average 40 percent Mn. About 38,000 tons of manganese ore is present in this deposit. The Cerro Iman is a large block of itabirite that contains about 40 percent Fe. The grade is variable and probably runs from less than 35 percent Fe to more than 50 percent Fe. No exploration has been done on this deposit. It is recommended that the Cerro de Iman area be geologically mapped in detail, and that a geological reconnaissance be made of the area that is between the Cuchilla de Corrales and the Cuchilla de Areycua/Cuchilla del Cerro Pelado area.

  7. Alteration of Serum Concentrations of Manganese, Iron, Ferritin, and Transferrin Receptor Following Exposure to Welding Fumes Among Career Welders

    PubMed Central

    Lu, Ling; Zhang, Long-lian; Li, G. Jane; Guo, Wenrui; Liang, Wannian; Zheng, Wei

    2014-01-01

    This study was performed to determine airborne manganese levels during welding practice and to establish the relationship between long-term, low-level exposure to manganese and altered serum concentrations of manganese, iron, and proteins associated with iron metabolism in career welders. Ninety-seven welders (average age of 36 years) who have engaged in electric arc weld in a vehicle manufacturer were recruited as the exposed group. Welders worked 7–8 h per day with employment duration of 1–33 years. Control subjects consisted of 91 employees (average age of 35 years) in the same factory but not in the welding profession. Ambient manganese levels in welders’ breathing zone were the highest inside the vehicle (1.5 ± 0.7 mg/m3), and the lowest in the center of the workshop (0.2 ± 0.05 mg/m3). Since the filter size was 0.8 ?m, it is possible that these values may be likely an underestimation of the true manganese levels. Serum levels of manganese and iron in welders were about three-fold (p < 0.01) and 1.2-fold (p < 0.01), respectively, higher than those of controls. Serum concentrations of ferritin and transferrin were increased among welders, while serum transferrin receptor levels were significantly decreased in comparison to controls. Linear regression analyses revealed a lack of association between serum levels of manganese and iron. However, serum concentrations of iron and ferritin were positively associated with years of welder experience (p < 0.05). Moreover, serum transferrin receptor levels were inversely associated with serum manganese concentrations (p < 0.05). These findings suggest that exposure to welding fume among welders disturbs serum homeostasis of manganese, iron, and the proteins associated with iron metabolism. Serum manganese may serve as a reasonable biomarker for assessment of recent exposure to airborne manganese. PMID:15713346

  8. Effect of Zero-Valent Iron Application on Cadmium Uptake in Rice Plants Grown in Cadmium-Contaminated Soils

    Microsoft Academic Search

    Toshihiro Watanabe; Yasutoshi Murata; Takashi Nakamura; Yuki Sakai; Mitsuru Osaki

    2009-01-01

    Cadmium (Cd) contamination in soils is a serious problem for crop production in the world. Zero-valent iron [Fe (0)] is a reactive material with reducing power capable of stabilizing toxic elements in a solution. In the present study, we examined the effect of zero-valent iron [Fe (0)] application on Cd accumulation in rice plants growing in Cd-contaminated paddy soils. The

  9. Manganese accumulates in iron-deficient rat brain regions in a heterogeneous fashion and is associated with neurochemical alterations

    Microsoft Academic Search

    Keith M. Erikson; Zakariya K. Shihabi; Judy L. Aschner; Michael Aschner

    2002-01-01

    Previous studies have shown that iron deficiency (ID) increases brain manganese (Mn), but specific regional changes have not\\u000a been addressed. Weanling rats were fed one of three semipurified diets: control (CN), iron deficient (ID), or iron deficient\\/manganese\\u000a fortified (IDMn+). Seven brain regions were analyzed for Mn concentration and amino acid (glutamate, glutamine, taurine, ?-aminobutyric\\u000a acid) concentrations. Both ID and IDMn+

  10. Transcriptional and Biochemical Effects of Cadmium and Manganese on the Defense System of Octopus vulgaris Paralarvae

    PubMed Central

    Salamone, Monica; Mazzola, Salvatore; Cuttitta, Angela

    2015-01-01

    Due to anthropogenic activities the relative concentrations of cadmium and manganese have increased in the marine environment. Cephalopods are able to accumulate such metals and, as inhabitant of coastal waters, Octopus vulgaris is continuously exposed to anthropogenic activities. Since no study is available on the effects of heavy metals at molecular level in developing octopuses, herein we exposed 1-day-old paralarvae for 24?h to 10, 100, and 1000??g/L of CdCl2 or MnCl2. Cd exerted a concentration-dependent inhibition of survival and a reduction in growth rate was shown while Mn exposure did not affect the survival rate even at the highest concentrations. Gene expression profiles of hsp70, sod, cat, and gst genes were analyzed by quantitative real-time PCR and defined patterns of transcription were observed. Moreover posttranscriptional analyses were also performed suggesting the impairment of metabolic functions, under strong oxidative conditions (as occurred in paralarvae exposed to Cd) or the complete detoxification events (as occurred in paralarvae exposed to Mn). PMID:25705660

  11. Transcriptional and Biochemical Effects of Cadmium and Manganese on the Defense System of Octopus vulgaris Paralarvae.

    PubMed

    Nicosia, Aldo; Salamone, Monica; Mazzola, Salvatore; Cuttitta, Angela

    2015-01-01

    Due to anthropogenic activities the relative concentrations of cadmium and manganese have increased in the marine environment. Cephalopods are able to accumulate such metals and, as inhabitant of coastal waters, Octopus vulgaris is continuously exposed to anthropogenic activities. Since no study is available on the effects of heavy metals at molecular level in developing octopuses, herein we exposed 1-day-old paralarvae for 24?h to 10, 100, and 1000??g/L of CdCl2 or MnCl2. Cd exerted a concentration-dependent inhibition of survival and a reduction in growth rate was shown while Mn exposure did not affect the survival rate even at the highest concentrations. Gene expression profiles of hsp70, sod, cat, and gst genes were analyzed by quantitative real-time PCR and defined patterns of transcription were observed. Moreover posttranscriptional analyses were also performed suggesting the impairment of metabolic functions, under strong oxidative conditions (as occurred in paralarvae exposed to Cd) or the complete detoxification events (as occurred in paralarvae exposed to Mn). PMID:25705660

  12. Rapid start-up of biofilters for removal of ammonium, iron and manganese from ground water

    Microsoft Academic Search

    Tamara Stembal; Marinko Markic; Felicita Briski; Laszlo Sipos

    2004-01-01

    Spontaneous formation of the active layer in biological filters for removal of iron, manganese and ammonium from ground water usually takes a few months. Inoculation of the new filters with well-established filter material is a common start-up procedure. An operational approach for inoculation of new filters using backwash sludge, instead of filter material, is elaborated here. The sludge is obtained

  13. Increasing dietary lipid and iron content decreases manganese superoxide dismutase activity in colonic mucosa

    Microsoft Academic Search

    Connye N. Kuratko

    1997-01-01

    Manganese superoxide dismutase (MnSOD) is an important mitochondrial antioxidant. Alteration in the regulation of MnSOD activity has been proposed to play a critical role in the development of many types of tumors. Colorectal cancer is one of the most common human malignancies and has been shown to be influenced by dietary factors. Two such dietary factors include lipid and iron.

  14. Oxidant Selection for the Treatment of Manganese (II), Iron (II), and Arsenic (III) in Groundwaters

    EPA Science Inventory

    In order to comply with the United States Environmental Protection Agency?s (U.S. EPA?s) arsenic standard and the manganese and iron secondary maximum contaminant levels (MCLs) in water (10µg/L, 50µg/L, and 300µg/L, respectively), many Midwestern water utilities must add a strong...

  15. Blood manganese concentration is elevated in infants with iron deficiency.

    PubMed

    Park, Sangkyu; Sim, Chang-Sun; Lee, Heun; Kim, Yangho

    2013-11-01

    The present study was done to determine whether blood Mn concentration is elevated in iron-deficient infants. Thirty-one infants with iron deficiency and thirty-six control subjects (6-24 months of age) were tested for blood Mn concentration, complete blood counts, serum ferritin, and serum iron/transferring iron-binding capacity (Fe/TIBC). All the 31 iron-deficient infants were treated with iron supplement; however, 19 of them underwent blood Mn checkup again in compliance with follow-up schedule when their ferritin levels returned to the normal range. Iron therapies were done for 1-6 months (mean, 2.8; standard deviation, 1.6) using ferric hydroxide-polymaltose complex (6 mg/kg Fe(3+) daily). Infants with iron deficiency had a higher mean blood Mn concentration than controls (2.550 vs. 1.499 ?g/dL, respectively). After iron therapy, the blood Mn levels of iron-deficient infants significantly decreased compared to their pre-therapy levels (2.045 vs. 2.971 ?g/dL, respectively), and their hemoglobin and ferritin levels significantly increased. After adjustment for covariates (e.g., age and breast-feeding), multiple linear regression models showed that increased blood Mn levels were significantly associated with low serum ferritin and hemoglobin levels, whereas with Fe/TIBC there was only a tendency. Our results indicate that iron deficiency increases blood Mn levels in infants, presumably by increasing Mn absorption. PMID:23955423

  16. Cadmium depletes cellular iron availability through enhancing ferroportin translation via iron responsive element.

    PubMed

    Sun, Li; Wang, Lixin; Wang, Zhe; He, Wei; Zhang, Shuping; Guo, Wenli; Qian, Yi; Ji, Hong; Rong, Haiqin; Liu, Sijin

    2015-04-01

    Cadmium (Cd) is a heavy metal that has detrimental effects on various organs. The widespread contamination of Cd in the environment, crops and food sources poses a severe threat to human health. Acute toxicities of Cd have been extensively investigated; however, the health impact of chronic low?dose exposure to Cd, particularly exposure under non?toxic concentrations, has yet to be elucidated. Furthermore, the toxic threshold of Cd is currently unknown. Ferroportin is the only known iron exporter in vertebrate cells, and it has an essential role in controlling iron egress from cells. To the best of our knowledge, the present study is the first to verify the regulation of ferroportin by Cd. Treatment with low?dose Cd (i.e. at sublethal concentrations, without undermining cell viability) increased the protein expression of ferroportin in macrophages, and this was associated with depleted cellular iron levels. Mechanistic investigations revealed that Cd modulated the ferroportin concentration at the translational level, via the iron responsive element located at the 5'?untranslated region of ferroportin. In conclusion, these data provide evidence for the molecular basis by which Cd alters cellular iron availability through elevating concentrations of ferroportin. PMID:25435269

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

    PubMed

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

    2015-04-01

    Huelva (South West Spain) and its surrounding municipalities represent one of the most polluted estuaries in the world owing to the discharge of mining and industrial related pollutants in their proximity. A biomonitoring study was conducted to assess exposure to arsenic and some trace metals (cadmium, mercury, manganese and lead) in urine and scalp hair from a representative sample of children aged 6-9 years (n=261). This is the only study simultaneously analyzing those five metal elements in children urine and hair. The potential contribution of gender, water consumption, residence area and body mass index on urinary and hair metal concentrations was also studied. Urine levels of cadmium and total mercury in a proportion (25-50%) of our children population living near industrial/mining areas might have an impact on health, likely due to environmental exposure to metal pollution. The only significant correlation between urine and hair levels was found for mercury. Children living near agriculture areas showed increased levels of cadmium and manganese (in urine) and arsenic (in hair). In contrast, decreased urine Hg concentrations were observed in children living near mining areas. Girls exhibited significantly higher trace metal concentrations in hair than boys. The greatest urine arsenic concentrations were found in children drinking well/spring water. Although human hair can be a useful tool for biomonitoring temporal changes in metal concentrations, levels are not correlated with those found in urine except for total mercury, thus providing additional information. PMID:25434277

  18. By Thomas S. Jones Manganese (Mn) is essential to iron and silicomanganese increased about 7%. consisted of, in tons, natural battery-grade ore,

    E-print Network

    Torgersen, Christian

    1 MANGANESE By Thomas S. Jones Manganese (Mn) is essential to iron and silicomanganese increased-fixing, The rate slowed for disposal of manganese 23,900; chemical-grade ore, 1,640; deoxidizing, and alloying-carbon no practical approaches exist for replacing it by Government still held inventories of manganese

  19. By Thomas S. Jones Manganese (Mn) is essential to iron and steel production by have been among the larger producers. World production of

    E-print Network

    Torgersen, Christian

    1 MANGANESE By Thomas S. Jones Manganese (Mn) is essential to iron and steel production by have, and alloying properties. manganese ferroalloys was estimated to have been in the same Currently, no practical component, has accounted for most domestic manganese which statistics have been rounded. demand, presently

  20. Cadmium accumulation and interactions with zinc, copper, and manganese, analysed by ICP-MS in a long-term Caco-2 TC7 cell model.

    PubMed

    Noël, Laurent; Huynh-Delerme, Céline; Guérin, Thierry; Huet, Hélène; Frémy, Jean-Marc; Kolf-Clauw, Martine

    2006-10-01

    The influence of long-term exposure to cadmium (Cd) on essential minerals was investigated using a Caco-2 TC7 cells and a multi-analytical tool: microwave digestion and inductively coupled plasma mass spectrometry. Intracellular levels, effects on cadmium accumulation, distribution, and reference concentration ranges of the following elements were determined: Na, Mg, Ca, Cr, Fe, Mn, Co, Ni, Cu, Zn, Mo, and Cd. Results showed that Caco-2 TC7 cells incubated long-term with cadmium concentrations ranging from 0 to 10 micromol Cd/l for 5 weeks exhibited a significant increase in cadmium accumulation. Furthermore, this accumulation was more marked in cells exposed long-term to cadmium compared with controls, and that this exposure resulted in a significant accumulation of copper and zinc but not of the other elements measured. Interactions of Cd with three elements: zinc, copper, and manganese were particularly studied. Exposed to 30 micromol/l of the element, manganese showed the highest inhibition and copper the lowest on cadmium intracellular accumulation but Zn, Cu, and Mn behave differently in terms of their mutual competition with Cd. Indeed, increasing cadmium in the culture medium resulted in a gradual and significant increase in the accumulation of zinc. There was a significant decrease in manganese from 5 micromol Cd/l exposure, and no variation was observed with copper. PMID:16937253

  1. New Iron(II) and Manganese(II) Complexes of Two Ultra-Rigid, Cross-Bridged Tetraazamacrocycles for Catalysis and Biomimicry

    E-print Network

    Hubin, Tim

    New Iron(II) and Manganese(II) Complexes of Two Ultra-Rigid, Cross-Bridged Tetraazamacrocycles abstraction reactions. Introduction Manganese and iron share with copper dominance over the vast realm and Photosystem II7 similarly illustrate the potency of manganese derivatives. In biomimicry and homogeneous ca

  2. Cadmium exposure affects iron acquisition in barley (Hordeum vulgare) seedlings.

    PubMed

    Astolfi, Stefania; Ortolani, Maria R; Catarcione, Giulio; Paolacci, Anna R; Cesco, Stefano; Pinton, Roberto; Ciaffi, Mario

    2014-12-01

    This study addresses the question of the interference between iron (Fe) nutrition and cadmium (Cd) toxicity at the level of growth performance, phytosiderophores (PS) release, micronutrient accumulation and expression of genes involved in Fe homeostasis in barley seedlings, a plant with strategy II-based response to Fe shortage. Cd exposure induced responses similar to those of genuine Fe deficiency also in Fe-sufficient plants. Most genes involved in PS biosynthesis and secretion (HvNAS3, HvNAS4, HvNAS6, HvNAS7, HvNAAT-A, HvDMAS1 and HvTOM1) induced by Fe deprivation were also significantly upregulated in the presence of Cd under Fe sufficient conditions. Accordingly, the enhanced expression of these genes in roots under Cd exposure was accompanied by an increase of PS release. However, induced expression of HvIRO2 and the downregulation of HvIDEF1 and HvIRT1, after Cd exposure, suggested the presence of a pathway that induces HvIRO2-mediated PS biosynthesis under Cd stress, which probably is not simply caused by Fe deficiency. The downregulation of HvIRT1 and HvNramp5 may represent a protective mechanism at transcriptional level against further Cd uptake by these transporters. These results likely indicate that Cd itself may be able to activate Fe acquisition mechanism in an Fe-independent manner. PMID:24724721

  3. Lipid production combined with biosorption and bioaccumulation of cadmium, copper, manganese and zinc by oleaginous microalgae Chlorella minutissima UTEX2341.

    PubMed

    Yang, JinShui; Cao, Jing; Xing, GuanLan; Yuan, HongLi

    2014-11-01

    Algae lipid production combined with heavy metal removal is a cost-effective and environment-friendly method for algae biofuel production and hazardous waste treatment. Chlorella minutissima UTEX 2341 had strong resistance to cadmium, copper, manganese and zinc ions under heterotrophic culture condition and could efficiently remove them through intracellular accumulation and extracellular immobilization. Meanwhile, lipid accumulation was not inhibited by heavy metals. Instead, the algae lipid content significantly increased by 21.07% and 93.90%, respectively with the addition of cadmium and copper. Furthermore, the heavy metal residue in lipid was within ?g range and satisfied the commercial standard. This artificial wastewater-algae biofuel-heavy-metal integrated utilization technology offered a new alternative solution to the problems of energy shortage and environmental pollution. PMID:25459865

  4. Potentiating effects of oxygen in lungs damaged by methylcyclopentadienyl manganese tricarbonyl, cadmium chloride, oleic acid, and antitumor drugs

    SciTech Connect

    Hakkinen, P.J.; Morse, C.C.; Martin, F.M.; Dalbey, W.E.; Haschek, W.M.; Witschi, H.R.

    1983-01-01

    The intraperitoneal administration of methylcyclopentadienyl manganese tricarbonyl (MMT) and cyclophosphamide, exposure to an aerosol of cadmium chloride, intravenous administration of oleic acid, and intratracheal instillation of bleomycin to young female BALB/c mice or CD/CR rats result in acute lung injury. Pulmonary morphology and lung collagen content were examined in animals treated with these chemicals alone or in combination with an elevated oxygen concentration (80%) in the inspired air. In mice, the development of fibrosis could be significantly enhanced if animals treated with MMT, cadmium chloride, cyclophosphamide, or bleomycin were exposed to 80% oxygen immediately following exposure to these agents. In rats only cyclophosphamide- and bleomycin-induced acute lung injury was potentiated by hyperoxia, resulting in significant enhancement of lung collagen content. The pathogenesis responsible for this differential species response of pulmonary injury to hyperoxia remains to be investigated.

  5. A novel separation and preconcentration method for traces of manganese, cobalt, zinc and cadmium using coagulation of colloidal silica.

    PubMed

    Nakajima, Junichi; Fujinami, Masanori; Oguma, Koichi

    2004-12-01

    A separation and preconcentration method has been developed for traces of heavy metals using coagulation of colloidal silica. An appropriate amount of colloidal silica was added to a sample solution, the pH was adjusted to 11 with tetramethylammonium hydroxide solution and calcium chloride solution was then added to coagulate the silica. The coagulated silica and solution were separated by centrifugation, and the silica was then treated with hydrofluoric and perchloric acids. The residue was taken up in dilute nitric acid and subjected to ICP-AES to determine manganese, cobalt, zinc and cadmium. The proposed method was successfully applied to analysis of river-water. PMID:15636526

  6. Characterization of cadmium manganese telluride (Cd1-xMnxTe) crystals grown by floating zone method

    NASA Astrophysics Data System (ADS)

    Hossain, A.; Gu, G. D.; Bolotnikov, A. E.; Camarda, G. S.; Cui, Y.; Gul, R.; Roy, U. N.; Yang, G.; Liu, T.; Zhong, R.; Schneeloch, J.; James, R. B.

    2014-09-01

    Recently, Cadmium Manganese Telluride (CMT) emerged as a promising material for roomtemperature X- and gamma-ray detectors. However, our studies revealed several material defects primarily related to growth processes that are impeding the production of large single crystals with high resistivity and high mobility-lifetime product. In this work, we characterized various defects in materials grown by the floating zone method, including twins, Te inclusions, and dislocations, using our unique facilities. We also fabricated detectors from selected CMT crystals and tested their performance. This paper discusses our detailed findings on the material's properties and the performance of fabricated CMT detectors.

  7. Iron deficiency increases blood cadmium levels in adolescents surveyed in KNHANES 2010-2011.

    PubMed

    Lee, Byung-Kook; Kim, Suk Hwan; Kim, Nam-Soo; Ham, Jung-O; Kim, Yangho

    2014-06-01

    Discrepancies have been reported in the relationships between iron and cadmium concentrations. The distribution of blood cadmium concentrations was assessed in a representative sample of Korean adolescents participating in the Korean National Health and Nutritional Examination Survey (KNHANES) 2010-2011, and the association between blood cadmium and iron concentrations was determined. This study was based on data from KNHANES, in which a rolling sampling design was used to perform a complex, stratified, multistage probability cluster survey of a representative sample of the noninstitutionalized civilian population in South Korea. Serum ferritin was categorized as low (<15.0 ?g/L), low normal (15.0-<30.0 ?g/L for girls, 15.0-<50.0 ?g/L for boys), or normal (?30.0 ?g/L for girls, ?50.0 ?g/L for boys), and the association between serum ferritin and blood cadmium concentrations was assessed after adjustment for various demographic and lifestyle factors. The geometric mean (GM) of blood cadmium was significantly higher among both boys and girls in the low than in the normal ferritin group. After controlling for covariates, multiple regression analysis showed that blood cadmium concentration was inversely correlated with serum ferritin concentration in both boys and girls. In conclusion, iron deficiency is associated with increased blood cadmium concentrations in a representative sample of Korean adolescents, as evaluated in KNHANES. PMID:24797808

  8. Coprecipitation mechanisms and products in manganese oxidation in the presence of cadmium

    USGS Publications Warehouse

    Hem, J.D.; Lind, C.J.

    1991-01-01

    Manganese oxidation products were precipitated in an aerated open-aqueous system where a continuous influx of mixed Mn2+ and Cd2+ solution was supplied and pH was maintained with an automated pH-stat adding dilute NaOH. X-ray diffraction and electron diffraction identified the solids produced as mixtures of Cd2Mn34+O8, Mn2+2Mn4+3O8, MnO2 (ramsdellite), and CdCO3. Mean oxidation numbers of the total precipitated Mn as great as 3.6 were reached during titrations. During subsequent aging in solution, oxidation numbers between 3.8 and 3.9 were reached in some precipitates in less than 40 days. Conditional oxidation rate constants calculated from a crystal-growth equation applied to titration data showed the overall precipitation rate, without considering manganese oxidation state in the precipitate, was increased by a factor of ~4 to ~7 when the mole ratio (Cd/Mn + Cd) of cadmium in the feed solution was 0.40 compared with rate constants for hausmannite (Mn2+Mn23+O4 precipitation under similar conditions but without accessory metals. Kinetic experiments were made to test effects of various Cd/Mn + Cd mole ratios and rates of addition of the feed solution, different temperatures from 5.0 to 35??C, and pH from 8.0 to 9.0. Oxidation rates were slower when the Cd mole ratio was less than 0.40. The rate increased by a factor of ~10 when pH was raised one-half unit. The effect of temperature on the rate constants was also substantial, but the meaning of this is uncertain because the rate of formation of Mn4+ oxide in the absence of Cd or other accessory metals was too slow to be measurable in titration experiments. The increased rate of Mn4+ oxide formation in the presence of Cd2+ can be ascribed to the formation of a labile adsorbed intermediate, CdMn2O4 Int, an analog of hausmannite, formed on precipitate surfaces at the beginning of the oxidation process. The increased lability of this structure, resulting from coordination-chemical behavior of Cd2+ during the titration, causes a rapid second-stage rearrangement and facilitates disproportionation of the Mn3+ ions. The Mn2+ ions thus released provide a positive feedback mechanism that couples the two steps of the conversion of Mn2+ to Mn4+ more closely than is possible when other metal ions besides manganese are not present. During aging of precipitates in contact with solutions, proportions of Cd2Mn3O8 and MnO2 increased at the expense of other precipitate components. ?? 1991.

  9. [Analysis on the variation characteristics of iron and manganese concentration and its genesis in Changtan Reservoir in Taizhou, Zhejiang Province].

    PubMed

    Liu, Shu-Yuan; Zheng, Chen; Yuan, Qi; Wang, Xian-Bing; Wang, Zi-Yan

    2014-10-01

    Changtan Reservoir in Taizhou City Zhejiang Province and its inflow rivers were surveyed in January and from April to December in 2013. Based on those data and the water quality monitoring data in Changtan Reservoir collected in previous years, the change characteristics of iron and manganese concentrations in source water reservoir were investigated. Furthermore, the causes of water pollution by iron and manganese were discussed based on the variation of water temperature, dissolved oxygen (DO) in reservoir with water depth. The results showed that the seasonal variation characteristics of iron and the manganese concentrations in reservoir were much in evidence. Their concentrations were high from June to August and the highest values over the years at the outlet of Changtan Reservoir were 2.38 mg · L(-1) and 1.24 mg · L(-1), respectively. The iron and the manganese concentrations exceeded the Surface Water Environment Quality Standard (GB 383822002) of 0.3 mg · L(-1) and 0.1 mg · L(-1) from May to October. And in 2013, their highest values in the reservoir outlet exceeded the standard by 5. 6 times and 12. 4 times, respectively. The maxima of iron and manganese concentrations in the major rivers were 0.89 mg · L(-1) and 0.56 mg · L(-1), which were lower than those in the reservoir outlet. The comprehensive analysis result indicated that the exogenous pollution was not the major source of iron and manganese in the reservoir. The iron and manganese concentration at the bottom of the reservoir reached the maximum in July, 2.42 mg · L(-1) and 1.20 mg · L(-1), respectively. The typical vertical distribution of temperature, DO and iron and manganese concentrations in the reservoir in summer showed that seasonal anoxic environment caused by the thermal stratification led to the release of iron manganese from the deposits. The endogenous pollution caused by thermal stratification effect was the direct cause for the high iron and manganese concentrations in water. To control iron and manganese pollution in drinking water resource reservoir, efficient and direct in situ water quality improvement and repair technology should be developed. PMID:25693372

  10. A zinc-resistant human epithelial cell line is impaired in cadmium and manganese import

    Microsoft Academic Search

    Estelle Rousselet; Pierre Richaud; Thierry Douki; Jocelyne Garcia Chantegrel; Alain Favier; Alexandre Bouron; Jean-Marc Moulis

    2008-01-01

    A human epithelial cell line (HZR) growing with high zinc concentrations has been analyzed for its ability to sustain high cadmium concentrations. Exposure to up to 200 µM of cadmium acetate for 24 h hardly impacted viability, whereas most of parental HeLa cells were killed by less than 10 µM of cadmium. Upon challenge by 35 fold higher cadmium concentrations than HeLa cells,

  11. Content of total iron, copper and manganese in liver of animals during hypokinesia, muscle activity and process of recovery

    NASA Technical Reports Server (NTRS)

    Potapovich, G. M.; Taneyeva, G. V.; Uteshev, A. B.

    1980-01-01

    It is shown that the content of total iron, copper and manganese in the liver of animals is altered depending on the intensity and duration of their swimming. Hypodynamia for 7 days does not alter the concentration of iron, but sufficiently increases the content of copper and manganese. The barometric factor effectively influences the maintenance of constancy in the content of microelements accumulated in the liver after intensive muscle activity.

  12. OPT3 is a phloem-specific iron transporter that is essential for systemic iron signaling and redistribution of iron and cadmium in arabidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Iron is essential for both plant growth and human health and nutrition. Cadmium, on the other hand, is a non-essential and highly toxic element that competes with iron for uptake and partitioning in plant tissues, posing a threat to crop productivity and human health. Knowledge of signaling mechanis...

  13. SECOND-SPHERE TUNING OF THE METAL ION REDUCTION POTENTIALS IN IRON AND MANGANESE SUPEROXIDE DISMUTASES

    Microsoft Academic Search

    Laurie E. Grove; Thomas C. Brunold

    2008-01-01

    Iron and manganese superoxide dismutases (Fe- and MnSODs, respectively) are metalloenzymes that catalyze the disproportionation of superoxide to dioxygen and hydrogen peroxide whereby the metal ion cycles between an oxidized and one-electron reduced state. Although Fe- and MnSODs exhibit similar protein and active-site structures, they display strict metal-ion specificities. To understand the origin of this specificity, we performed spectroscopic and

  14. Differential response of salt-marsh species to variation of iron and manganese

    Microsoft Academic Search

    J. Rozema; E. Luppes; R. Broekman

    1985-01-01

    Salt-marsh plants of the lower, middle and upper marsh were compared in their response to iron and manganese. The species studied showed differential sensitivity to high concentrations of Fe (1 000 µM) and Mn (10 000 µM) in hydroculture experiments, species of the lower marsh being more resistant than species of the upper marsh. Fe and Mn concentrations in the

  15. Copper, Chromium, Manganese, Iron, Nickel, and Zinc Levels in Biological Samples of Diabetes Mellitus Patients

    Microsoft Academic Search

    Tasneem Gul Kazi; Hassan Imran Afridi; Naveed Kazi; Mohammad Khan Jamali; Mohammad Bilal Arain; Nussarat Jalbani; Ghulam Abbas Kandhro

    2008-01-01

    There is accumulating evidence that the metabolism of several trace elements is altered in diabetes mellitus and that these\\u000a nutrients might have specific roles in the pathogenesis and progress of this disease. The aim of present study was to compare\\u000a the level of essential trace elements, chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), and zinc (Zn) in

  16. Removal of ammonia, iron and manganese from groundwaters of northern Croatia—pilot plant studies

    Microsoft Academic Search

    Tamara Štembal; Marinko Marki?; Nataša Ribi?i?; Felicita Briški; Laszlo Sipos

    2005-01-01

    The removal of iron, manganese and ammonia from groundwater originating from four different locations in northern Croatia was studied. Four pilot plants, mainly differing in their aeration systems and operation pressures, have been used. Quartz sand, coated with a naturally formed layer of MnO2 and a biofilm containing micro-organisms, were used as filter media. The bacteria of the genus Siderocapsa,

  17. Carbamazepine oxidation catalyzed by iron and manganese porphyrins supported on aminofunctionalized matrices

    Microsoft Academic Search

    André L. Faria; Tatiana C. O. Mac Leod; Marilda D. Assis

    2008-01-01

    This work describes the catalytic activity of manganese and iron porphyrins, Mn and Fe(TFPP)Cl, covalently immobilized on the aminofunctionalized supports montmorillonite K-10 (MontX) and silica (SilX), where X=1 or 2 represents the length of the organic chain (“arms”) binding the metalloporphyrin to the support. These systems were characterized by UV–vis and Electronic Paramagnetic Resonance (EPR), and they were used as

  18. Iron Acquisition by Phytosiderophores Contributes to Cadmium Tolerance1[OA

    PubMed Central

    Meda, Anderson R.; Scheuermann, Enrico B.; Prechsl, Ulrich E.; Erenoglu, Bülent; Schaaf, Gabriel; Hayen, Heiko; Weber, Günther; von Wirén, Nicolaus

    2007-01-01

    Based on the ability of phytosiderophores to chelate other heavy metals besides iron (Fe), phytosiderophores were suggested to prevent graminaceous plants from cadmium (Cd) toxicity. To assess interactions between Cd and phytosiderophore-mediated Fe acquisition, maize (Zea mays) plants were grown hydroponically under limiting Fe supply. Exposure to Cd decreased uptake rates of 59Fe(III)-phytosiderophores and enhanced the expression of the Fe-phytosiderophore transporter gene ZmYS1 in roots as well as the release of the phytosiderophore 2?-deoxymugineic acid (DMA) from roots under Fe deficiency. However, DMA hardly mobilized Cd from soil or from a Cd-loaded resin in comparison to the synthetic chelators diaminetriaminepentaacetic acid and HEDTA. While nano-electrospray-high resolution mass spectrometry revealed the formation of an intact Cd(II)-DMA complex in aqueous solutions, competition studies with Fe(III) and zinc(II) showed that the formed Cd(II)-DMA complex was weak. Unlike HEDTA, DMA did not protect yeast (Saccharomyces cerevisiae) cells from Cd toxicity but improved yeast growth in the presence of Cd when yeast cells expressed ZmYS1. When supplied with Fe-DMA as a Fe source, transgenic Arabidopsis (Arabidopsis thaliana) plants expressing a cauliflower mosaic virus 35S-ZmYS1 gene construct showed less growth depression than wild-type plants in response to Cd. These results indicate that inhibition of ZmYS1-mediated Fe-DMA transport by Cd is not related to Cd-DMA complex formation and that Cd-induced phytosiderophore release cannot protect maize plants from Cd toxicity. Instead, phytosiderophore-mediated Fe acquisition can improve Fe uptake in the presence of Cd and thereby provides an advantage under Cd stress relative to Fe acquisition via ferrous Fe. PMID:17337530

  19. Cadmium Toxicity Induced Alterations in the Root Proteome of Green Gram in Contrasting Response towards Iron Supplement

    PubMed Central

    Muneer, Sowbiya; Hakeem, Khalid Rehman; Mohamed, Rozi; Lee, Jeong Hyun

    2014-01-01

    Cadmium signifies a severe threat to crop productivity and green gram is a notably iron sensitive plant which shows considerable variation towards cadmium stress. A gel-based proteomics analysis was performed with the roots of green gram exposed to iron and cadmium combined treatments. The resulting data show that twenty three proteins were down-regulated in iron-deprived roots either in the absence (?Fe/?Cd) or presence (?Fe/+Cd) of cadmium. These down-regulated proteins were however well expressed in roots under iron sufficient conditions, even in the presence of cadmium (+Fe/+Cd). The functional classification of these proteins determined that 21% of the proteins are associated with nutrient metabolism. The other proteins in higher quantities are involved in either transcription or translation regulation, and the rest are involved in biosynthesis metabolism, antioxidant pathways, molecular chaperones and stress response. On the other hand, several protein spots were also absent in roots in response to iron deprivation either in absence (?Fe/?Cd) or presence (?Fe/+Cd) of cadmium but were well expressed in the presence of iron (+Fe/+Cd). Results suggest that green gram plants exposed to cadmium stress are able to change the nutrient metabolic balance in roots, but in the mean time regulate cadmium toxicity through iron supplements. PMID:24739807

  20. OPT3 Is a Component of the Iron-Signaling Network between Leaves and Roots and Misregulation of OPT3 Leads to an Over-Accumulation of Cadmium in Seeds

    PubMed Central

    Mendoza-Cózatl, David G.; Xie, Qingqing; Akmakjian, Garo Z.; Jobe, Timothy O.; Patel, Ami; Stacey, Minviluz G.; Song, Lihui; Demoin, Dustin Wayne; Jurisson, Silvia S.; Stacey, Gary; Schroeder, Julian I.

    2014-01-01

    Plants and seeds are the main dietary sources of zinc, iron, manganese, and copper, but are also the main entry point for toxic elements such as cadmium into the food chain. We report here that an Arabidopsis oligopeptide transporter mutant, opt3-2, over-accumulates cadmium (Cd) in seeds and roots but, unexpectedly, under-accumulates Cd in leaves. The cadmium distribution in opt3-2 differs from iron, zinc, and manganese, suggesting a metal-specific mechanism for metal partitioning within the plant. The opt3-2 mutant constitutively up-regulates the Fe/Zn/Cd transporter IRT1 and FRO2 in roots, indicative of an iron-deficiency response. No genetic mutants that impair the shoot-to-root signaling of iron status in leaves have been identified. Interestingly, shoot-specific expression of OPT3 rescues the Cd sensitivity and complements the aberrant expression of IRT1 in opt3-2 roots, suggesting that OPT3 is required to relay the iron status from leaves to roots. OPT3 expression was found in the vasculature with preferential expression in the phloem at the plasma membrane. Using radioisotope experiments, we found that mobilization of Fe from leaves is severely affected in opt3-2, suggesting that Fe mobilization out of leaves is required for proper trace-metal homeostasis. When expressed in yeast, OPT3 does not localize to the plasma membrane, precluding the identification of the OPT3 substrate. Our in planta results show that OPT3 is important for leaf phloem-loading of iron and plays a key role regulating Fe, Zn, and Cd distribution within the plant. Furthermore, ferric chelate reductase activity analyses provide evidence that iron is not the sole signal transferred from leaves to roots in leaf iron status signaling. PMID:24880337

  1. THE EFFECTS OF IRON(II) ON ARSENIC(III) OXIDATION AND ARSENIC SORPTION/DESORPTION ON MANGANESE OXIDES

    E-print Network

    Sparks, Donald L.

    THE EFFECTS OF IRON(II) ON ARSENIC(III) OXIDATION AND ARSENIC SORPTION/DESORPTION ON MANGANESE © 2014 Yun Wu All Rights Reserved #12;THE EFFECTS OF IRON(II) ON ARSENIC(III) OXIDATION AND ARSENIC, Caroline Golt on arsenic speciation and UD Soil Test Lab. I thank all current and previous members

  2. Reduction of cadmium toxicity to green microalga Stichococcus bacillaris by manganese

    Microsoft Academic Search

    Tadeusz Skowrofiski; Barbara Pawlik; Marek Jakubowski

    1988-01-01

    Investigations of cadmium toxicity fo ndcroorganisms are now more concerned with the interactions of cadmiumwith different environmental factors and other metals. The interactions are complex and bave not been thoroughly studied yet. Metal interactions may assume the form of synergism characterized by increase in toxicity,but also of antagonism in which one metal reduces the toxicity of another. Apart from cadmium

  3. OPT3 Is a Phloem-Specific Iron Transporter That Is Essential for Systemic Iron Signaling and Redistribution of Iron and Cadmium in Arabidopsis[W][OPEN

    PubMed Central

    Zhai, Zhiyang; Gayomba, Sheena R.; Jung, Ha-il; Vimalakumari, Nanditha K.; Piñeros, Miguel; Craft, Eric; Rutzke, Michael A.; Danku, John; Lahner, Brett; Punshon, Tracy; Guerinot, Mary Lou; Salt, David E.; Kochian, Leon V.; Vatamaniuk, Olena K.

    2014-01-01

    Iron is essential for both plant growth and human health and nutrition. Knowledge of the signaling mechanisms that communicate iron demand from shoots to roots to regulate iron uptake as well as the transport systems mediating iron partitioning into edible plant tissues is critical for the development of crop biofortification strategies. Here, we report that OPT3, previously classified as an oligopeptide transporter, is a plasma membrane transporter capable of transporting transition ions in vitro. Studies in Arabidopsis thaliana show that OPT3 loads iron into the phloem, facilitates iron recirculation from the xylem to the phloem, and regulates both shoot-to-root iron signaling and iron redistribution from mature to developing tissues. We also uncovered an aspect of crosstalk between iron homeostasis and cadmium partitioning that is mediated by OPT3. Together, these discoveries provide promising avenues for targeted strategies directed at increasing iron while decreasing cadmium density in the edible portions of crops and improving agricultural productivity in iron deficient soils. PMID:24867923

  4. Expanding the menu for carnivorous plants: uptake of potassium, iron and manganese by carnivorous pitcher plants.

    PubMed

    Adlassnig, Wolfram; Steinhauser, Georg; Peroutka, Marianne; Musilek, Andreas; Sterba, Johannes H; Lichtscheidl, Irene K; Bichler, Max

    2009-12-01

    Carnivorous plants use animals as fertiliser substitutes which allow them to survive on nutrient deficient soils. Most research concentrated on the uptake of the prey's nitrogen and phosphorus; only little is known on the utilisation of other elements. We studied the uptake of three essential nutrients, potassium, iron and manganese, in three species of carnivorous pitcher plants (Cephalotus follicularis LaBilladiere, Sarracenia purpureaL., Heliamphora nutans Bentham). Using relatively short-lived and gamma-emitting radiotracers, we significantly improved the sensitivity compared to conventional protocols and gained the following results. We demonstrated the uptake of trace elements like iron and manganese. In addition, we found direct evidence for the uptake of potassium into the pitcher tissue. Potassium and manganese were absorbed to virtually 100% if offered in physiological concentrations or below in Cephalotus. Analysis of pitcher fluid collected in the natural habitat showed that uptake was performed here as efficiently as in the laboratory. The absorption of nutrients is an active process depending on living glandular cells in the pitcher epidermis and can be inhibited by azide. Unphysiologically high amounts of nutrients were taken up for a short time, but after a few hours the absorbing cells were damaged, and uptake stopped. Absorption rates of pitcher leaves from plants under controlled conditions varied highly, indicating that each trap is functionally independent. The comparison of minerals in typical prey with the plants' tissues showed that a complete coverage of the plants' needs by prey capture is improbable. PMID:19428263

  5. Iron depletion increases manganese uptake and potentiates apoptosis through ER stress

    PubMed Central

    Seo, Young Ah; Li, Yuan; Wessling-Resnick, Marianne

    2013-01-01

    Iron deficiency is a risk factor for manganese (Mn) accumulation. Excess Mn promotes neurotoxicity but the mechanisms involved and whether iron depletion might affect these pathways is unknown. To study Mn intoxication in vivo, iron deficient and control rats were intranasally instilled with 60 mg MnCl2/kg over 3 weeks. TUNEL staining of olfactory tissue revealed that Mn exposure induced apoptosis and that iron deficiency potentiated this effect. In vitro studies using the dopaminergic SH-SY5Y cell line confirmed that Mn-induced apoptosis was enhanced by iron depletion using the iron chelator desferrioxamine. Mn has been reported to induce apoptosis through endoplasmic reticulum stress. In SH-SY5Y cells, Mn exposure induced the ER stress genes glucose regulated protein 94 (GRP94) and C/EBP homologous protein (CHOP). Increased phosphorylation of the eukaryotic translation initiation factor 2? (phospho-eIF2?) was also observed. These effects were accompanied by the activation of ER resident enzyme caspase-12, and the downstream apoptotic effector caspase-3 was also activated. All of the Mn-induced responses were enhanced by DFO treatment. Inhibitors of ER stress and caspases significantly blocked Mn-induced apoptosis and its potentiation by DFO, indicating that ER stress and subsequent caspase activation underlie cell death. Taken together, these data reveal that Mn induces neuronal cell death through ER stress and the UPR response pathway and that this apoptotic effect is potentiated by iron deficiency most likely through upregulation of DMT1. PMID:23764342

  6. The photochemistry of manganese and the origin of banded iron formations

    NASA Technical Reports Server (NTRS)

    Anbar, A. D.; Holland, H. D.

    1992-01-01

    The origin of the deposition of superior-type Precambrian banded iron formations (BIFs) is investigated in experiments where the effect of UV radiation on dissolved manganese was studied to determine if the commonly accepted photochemical model for BIF formation is consistent with the distribution of Mn in BIFs. Solutions containing 0.56 M NaCl and about 180 microM MnCl2, with or without 3 to 200 microM FeCl2 were irradiated with filtered and unfiltered UV light for up to 8 hrs; the solutions were deaerated and buffered to a pH of 7, and the experiments were conducted under oxygen-free atmosphere. Data on the rate of manganese photooxidation confirmed that a photochemical model for the origin of oxide facies BIFs is consistent with field observations.

  7. Thermodynamic and kinetic studies of biosorption of iron and manganese from aqueous medium using rice husk ash

    NASA Astrophysics Data System (ADS)

    Adekola, F. A.; Hodonou, D. S. S.; Adegoke, H. I.

    2014-11-01

    The adsorption behavior of rice husk ash with respect to manganese and iron has been studied by batch methods to consider its application for water and waste water treatment. The optimum conditions of adsorption were determined by investigating the effect of initial metal ion concentration, contact time, adsorbent dose, pH value of aqueous solution and temperature. Adsorption equilibrium time was observed at 120 min. The adsorption efficiencies were found to be pH dependent. The equilibrium adsorption experimental data were found to fit the Langmuir, Freundlich and Temkin isotherms for iron, but fitted only Langmuir isotherm for manganese. The pseudo-second order kinetic model was found to describe the manganese and iron kinetics more effectively. The thermodynamic experiment revealed that the adsorption processes involving both metals were exothermic. The adsorbent was finally applied to typical raw water with initial manganese and iron concentrations of 3.38 mg/l for Fe and 6.28 mg/l, respectively, and the removal efficiency was 100 % for Mn and 70 % for Fe. The metal ions were desorbed from the adsorbent using 0.01 M HCl, it was found to quantitatively remove 67 and 86 % of Mn and Fe, respectively, within 2 h. The results revealed that manganese and iron are considerably adsorbed on the adsorbent and could be an economic method for the removal of these metals from aqueous solutions.

  8. Significance of concentrations of lead, cadmium, and iron in the plumage of the feral pigeon

    Microsoft Academic Search

    Marifin Janiga; Blanka Mafikovskfi; Monika Bobal'ová; Gabriela ?ur?ová

    1990-01-01

    Lead, cadmium, and iron contamination was examined in the plumage of feral pigeons. Metal contamination in pigeons from different regions in Bratislava or in different seasons did not differ significantly; seasonal type of food did not significantly influence the concentrations. The blood of birds was examined for the presence of complement fixing antibodies toChlamydia psittaci. Birds with antibodies did not

  9. Sex-specific Profiles of Blood Metal Levels Associated with Metal-Iron Interactions.

    PubMed

    Lee, Byung-Kook; Kim, Yangho

    2014-09-01

    The mechanisms by which iron is absorbed are similar to those of divalent metals, particularly manganese, lead, and cadmium. These metals, however, show different toxicokinetics in relation to menarche or menopause, although their interaction with iron is the same. This review focuses on the kinetics of these three toxic metals (manganese, lead, and cadmium) in relation to menarche, pregnancy, and menopause. The iron-manganese interaction is the major factor determining sex-specific differences in blood manganese levels throughout the whole life cycle. The effects of estrogen overshadow the association between iron deficiency and increased blood lead concentrations, explaining why women, despite having lower ferritin concentrations, have lower blood lead concentrations than men. Iron deficiency is associated with elevated cadmium levels in premenopausal women, but not in postmenopausal women or men; these findings indicate that sex-specific differences in cadmium levels at older ages are not due to iron-cadmium interactions, and that further studies are required to identify the source of these differences. In summary, the potential causes of sex-specific differences in the blood levels of manganese, lead, and cadmium differ from each other, although all these three metals are associated with iron deficiency. Therefore, other factors such as estrogen effects, or absorption rate as well as iron deficiency, should be considered when addressing environmental exposure to toxic metals and sex-specific differences in the blood levels of these metals. PMID:25379323

  10. Environmentally acquired lead, cadmium, and manganese in the cattle egret, Bubulcus ibis, and the laughing gull, Larus atricilla.

    PubMed

    Hulse, M; Mahoney, J S; Schroder, G D; Hacker, C S; Pier, S M

    1980-01-01

    The concentrations of lead, cadmium, and manganese in the tissues of cattle egrets (Bubulcus ibis) and laughing gulls (Larus atricilla) gathered from the Galveston Bay region of Texas were compared, to determine if different patterns of accumulation exist. Their levels in these species were within the range reported for other bird species. Lead levels in bone were comparable, but gulls had more lead in brain, kidney and liver tissues than the egrets, which suggested a higher rate of accumulation or exposure. Due to their high abundance and comparable positions in the estaurine and terrestrial food webs, it is suggested that Bubulcus ibis and Larus atricilla may serve as convenient biological indicators to monitor potentially toxic substances in these ecosystems. PMID:7189395

  11. Effects of zinc, iron and copper deficiencies on cadmium in tissues of Japanese quail. [Coturnix coturnix japonica

    SciTech Connect

    Fox, M.R.S.; Tao, S.H.; Stone, C.L.; Fry, B.E. Jr.

    1984-03-01

    Experiments with young Japanese quail were conducted to determine whether combined moderate deficiencies of zinc, iron and copper would cause greater uptake and tissue retention of cadmium than the single deficiencies. Birds were fed the experimental diets containing 62 ppb cadmium from hatching to 16 days of age. On day 9 each bird received a dose of /sup 109/CdCl/sub 2/ in its diet. On day 10, the duodenal and jejunal-ileal tissues contained large amounts of cadmium, and there were many significant effects of treatment on cadmium-109 retention in the livers and kidneys. At day 16, zinc deficiency caused increased cadmium in the liver, whereas iron and copper deficiencies each caused increased cadmium in the kidneys. Combined deficiencies had little or no greater effect than single deficiencies and in some cases the combined effect was less than that of a single deficiency. 13 references, 11 tables.

  12. Cadmium

    Cancer.gov

    Cadmium is a natural element found in tiny amounts in air, water, soil, and food. All soils and rocks, including coal and mineral fertilizers, contain some cadmium. Most cadmium used in the United States is extracted during the production of other metals such as zinc, lead, and copper. Cadmium does not corrode easily and has been used to manufacture batteries, pigments, metal coatings, and plastics.

  13. THEORETICAL TECHNIQUE FOR DETERMINING THE CUMULATIVE IMPACT OF IRON AND MANGANESE OXIDATION IN STREAMS RECEIVING COAL-MINE DISCHARGE.

    USGS Publications Warehouse

    Bobay, Keith E.; Banaszak, Konrad J.

    1985-01-01

    Two U. S. Geological Survey computer programs are modified and linked to predict the cumulative impact of iron and manganese oxidation in coal-mine discharge on the dissolved-chemical quality of a receiving stream. The coupled programs calculate the changes in dissolved-iron, dissolved-manganese, and dissolved-oxygen concentrations, and the pH of surface water downstream from the discharge. The cumulative impact of representative discharges from several coal mines on stream quality in a small watershed in southwestern Indiana was simulated to determine the effectiveness and sensitivity of the coupled programs.

  14. Effects of exogenous gibberellic acid3 on iron and manganese plaque amounts and iron and manganese uptake in rice.

    PubMed

    Guo, Yue; Zhu, Changhua; Gan, Lijun; Ng, Denny; Xia, Kai

    2015-01-01

    Gibberellins (GA) regulate various components of plant development. Iron and Mn plaque result from oxiding and hydroxiding Fe and Mn, respectively, on the roots of aquatic plant species such as rice (Oryza sativa L.). In this study, we found that exogenous gibberellic acid3 (GA3) spray decreased Fe plaque, but increased Mn plaque, with applications of Kimura B nutrient solution. Similar effects from GA3, leading to reduced Fe plaque and increased Mn plaque, were also found by scanning electron microscopy and energy dispersive X-ray spectrometric microanalysis. Reduced Fe plaque was observed after applying GA3 to the groups containing added Fe2+ (17 and 42 mg•L(-1)) and an increasing trend was detected in Mn plaques of the Mn2+ (34 and 84 mg•L(-1)) added treatments. In contrast, an inhibitor of GA3, uniconazole, reversed the effects of GA3. The uptake of Fe or Mn in rice plants was enhanced after GA3 application and Fe or Mn plaque production. Strong synergetic effects of GA3 application on Fe plaque production were detected. However, no synergetic effects on Mn plaque production were detected. PMID:25710173

  15. Effects of Exogenous Gibberellic Acid3 on Iron and Manganese Plaque Amounts and Iron and Manganese Uptake in Rice

    PubMed Central

    Guo, Yue; Zhu, Changhua; Gan, Lijun; Ng, Denny; Xia, Kai

    2015-01-01

    Gibberellins (GA) regulate various components of plant development. Iron and Mn plaque result from oxiding and hydroxiding Fe and Mn, respectively, on the roots of aquatic plant species such as rice (Oryza sativa L.). In this study, we found that exogenous gibberellic acid3 (GA3) spray decreased Fe plaque, but increased Mn plaque, with applications of Kimura B nutrient solution. Similar effects from GA3, leading to reduced Fe plaque and increased Mn plaque, were also found by scanning electron microscopy and energy dispersive X-ray spectrometric microanalysis. Reduced Fe plaque was observed after applying GA3 to the groups containing added Fe2+ (17 and 42 mg•L-1) and an increasing trend was detected in Mn plaques of the Mn2+ (34 and 84 mg•L-1) added treatments. In contrast, an inhibitor of GA3, uniconazole, reversed the effects of GA3. The uptake of Fe or Mn in rice plants was enhanced after GA3 application and Fe or Mn plaque production. Strong synergetic effects of GA3 application on Fe plaque production were detected. However, no synergetic effects on Mn plaque production were detected. PMID:25710173

  16. Zinc, cadmium and manganese uptake by soybean from two zinc- and cadmium-amended Coastal Plain soils

    SciTech Connect

    White, M.C. (Maryland Environmental Service, Annapolis); Chaney, R.L.

    1980-03-01

    Two Coastal Plain soils were used to evaluate the effects of organic matter and Fe and Mn hydrous oxides on Zn phytotoxicity, and on Zn, Cd, and Mn uptake by soybean seedlings. Fertilized Pocomoke sl and Sassafras sl were limed to pH 5.5 and 6.3 with CaCO/sub 3/ when adding Zn (six levens between 1.3 and 196 mg/kg at pH 5.5; seven levels between 1.3 and 524 mg/kg at pH 6.3). Cadmium was added at 1% of the added Zn. Beeson soybean (Glycine max L. Merr.) was grown 4 weeks, and the trifoliolate leaves evaluated for dry weight yield and for their Zn, Cd, and Mn concentrations. The higher organic matter Pocomoke soil was more effective than the Sassafras soil in reducing metal uptake, and Zn phytoxicity. Foliar Zn levels associated with yield reduction of soybean grown on Pocomoke differed with soil pH. Cadmium uptake was significantly lower on the Pocomoke soil. Foliar Mn increased to reported phytotoxic levels (> 500 mg/kg) with increased added Zn only on the Sassafras soil at pH 6.3. DTPA-extractable Zn and Cd were linear functions of added Zn and Cd for both soils; 0.01M CaCl/sub 2/-extractable Zn and Cd were curvilinear (increasing slope) functions for the Sassafras and linear for the Pocomoke soil. Thus, soil type can strongly influence Zn, Cd, and Mn uptake as well as Zn phytotoxicity to soybean. Soil organic matter appears to be more important than hydrous oxides of Fe and Mn in moderating the effects of excessive soil Zn and limiting Zn and Cd uptake. Induced metal toxicities (Mn) may depend on many factors, and should be considered an integral part of any characterization of specific metal phytotoxicities (e.g. Zn).

  17. Intestinal absorption of dietary cadmium in women depends on body iron stores and fiber intake.

    PubMed Central

    Berglund, M; Akesson, A; Nermell, B; Vahter, M

    1994-01-01

    Measurements of intake and uptake of cadmium in relation to diet composition were carried out in 57 nonsmoking women, 20-50 years of age. A vegetarian/high-fiber diet and a mixed-diet group were constructed based on results from a food frequency questionnaire. Duplicate diets and the corresponding feces were collected during 4 consecutive days in parallel with dietary recording of type and amount of food ingested for determination of the dietary intake of cadmium and various nutrients. Blood and 24-hr urine samples were collected for determination of cadmium, hemoglobin, ferritin, and zinc. There were no differences in the intake of nutrients between the mixed-diet and the high-fiber diet groups, except for a significantly higher intake of fiber (p < 0.001) and cadmium (p < 0.002) in the high-fiber group. Fecal cadmium corresponded to 98% in the mixed-diet group and 100% in the high-fiber diet group. No differences in blood cadmium (BCd) or urinary cadmium (UCd) between groups could be detected. There was a tendency toward higher BCd and UCd concentrations with increasing fiber intake; however, the concentrations were not statistically significant at the 5% level, indicating an inhibitory effect of fiber on the gastrointestinal absorption of cadmium. Sixty-seven percent of the women had serum ferritin < 30 micrograms/l, indicating reduced body iron stores, which were highly associated with higher BCd (irrespective of fiber intake). BCd was mainly correlated with UCd, serum ferritin, age, anf fibre intake. UCd and serum ferritin explained almost 60% of the variation in BCd.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 1. Figure 2. Figure 3. A Figure 3. B Figure 4. Figure 5. PMID:7713018

  18. The proteome of copper, iron, zinc, and manganese micronutrient deficiency in Chlamydomonas reinhardtii.

    PubMed

    Hsieh, Scott I; Castruita, Madeli; Malasarn, Davin; Urzica, Eugen; Erde, Jonathan; Page, M Dudley; Yamasaki, Hiroaki; Casero, David; Pellegrini, Matteo; Merchant, Sabeeha S; Loo, Joseph A

    2013-01-01

    Trace metals such as copper, iron, zinc, and manganese play important roles in several biochemical processes, including respiration and photosynthesis. Using a label-free, quantitative proteomics strategy (MS(E)), we examined the effect of deficiencies in these micronutrients on the soluble proteome of Chlamydomonas reinhardtii. We quantified >10(3) proteins with abundances within a dynamic range of 3 to 4 orders of magnitude and demonstrated statistically significant changes in ~200 proteins in each metal-deficient growth condition relative to nutrient-replete media. Through analysis of Pearson's coefficient, we also examined the correlation between protein abundance and transcript abundance (as determined via RNA-Seq analysis) and found moderate correlations under all nutritional states. Interestingly, in a subset of transcripts known to significantly change in abundance in metal-replete and metal-deficient conditions, the correlation to protein abundance is much stronger. Examples of new discoveries highlighted in this work include the accumulation of O(2) labile, anaerobiosis-related enzymes (Hyd1, Pfr1, and Hcp2) in copper-deficient cells; co-variation of Cgl78/Ycf54 and coprogen oxidase; the loss of various stromal and lumenal photosynthesis-related proteins, including plastocyanin, in iron-limited cells; a large accumulation (from undetectable amounts to over 1,000 zmol/cell) of two COG0523 domain-containing proteins in zinc-deficient cells; and the preservation of photosynthesis proteins in manganese-deficient cells despite known losses in photosynthetic function in this condition. PMID:23065468

  19. The Proteome of Copper, Iron, Zinc, and Manganese Micronutrient Deficiency in Chlamydomonas reinhardtii*

    PubMed Central

    Hsieh, Scott I.; Castruita, Madeli; Malasarn, Davin; Urzica, Eugen; Erde, Jonathan; Page, M. Dudley; Yamasaki, Hiroaki; Casero, David; Pellegrini, Matteo; Merchant, Sabeeha S.; Loo, Joseph A.

    2013-01-01

    Trace metals such as copper, iron, zinc, and manganese play important roles in several biochemical processes, including respiration and photosynthesis. Using a label-free, quantitative proteomics strategy (MSE), we examined the effect of deficiencies in these micronutrients on the soluble proteome of Chlamydomonas reinhardtii. We quantified >103 proteins with abundances within a dynamic range of 3 to 4 orders of magnitude and demonstrated statistically significant changes in ?200 proteins in each metal-deficient growth condition relative to nutrient-replete media. Through analysis of Pearson's coefficient, we also examined the correlation between protein abundance and transcript abundance (as determined via RNA-Seq analysis) and found moderate correlations under all nutritional states. Interestingly, in a subset of transcripts known to significantly change in abundance in metal-replete and metal-deficient conditions, the correlation to protein abundance is much stronger. Examples of new discoveries highlighted in this work include the accumulation of O2 labile, anaerobiosis-related enzymes (Hyd1, Pfr1, and Hcp2) in copper-deficient cells; co-variation of Cgl78/Ycf54 and coprogen oxidase; the loss of various stromal and lumenal photosynthesis-related proteins, including plastocyanin, in iron-limited cells; a large accumulation (from undetectable amounts to over 1,000 zmol/cell) of two COG0523 domain-containing proteins in zinc-deficient cells; and the preservation of photosynthesis proteins in manganese-deficient cells despite known losses in photosynthetic function in this condition. PMID:23065468

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

    Microsoft Academic Search

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

    2008-01-01

    Concentrations of arsenic, cadmium, chromium, lead, manganese, mercury and selenium were examined in the down feathers and\\u000a eggs of female common eiders (Somateria mollissima) from Amchitka and Kiska Islands in the Aleutian Chain of Alaska to determine whether there were (1) differences between\\u000a levels in feathers and eggs, (2) differences between the two islands, (3) positive correlations between metal levels

  1. Immobilization of Arsenic and Manganese in Contaminated Groundwater by Permeable Reactive Barriers Using Zero Valent Iron and Sheep Manure

    Microsoft Academic Search

    Wahyu Wilopo; Keiko Sasaki; Tsuyoshi Hirajima; Toshiro Yamanaka

    2008-01-01

    A permeable reactive barriers (PRBs) column test was carried out to remove arsenic (As) and manganese (Mn) from groundwater using zero valent iron (ZVI), sheep manure, compost and woodchips as reactive materials. Arsenic was mainly immobilized through sorption and co-precipitation with iron-bearing minerals, and also possibly precipitation as FeAsO4. The presence of sulfate-reducing bacteria (SRB) in the inoculated column was

  2. Borrelia burgdorferi, a pathogen that lacks iron, encodes manganese-dependent superoxide dismutase essential for resistance to streptonigrin.

    PubMed

    Troxell, Bryan; Xu, Haijun; Yang, X Frank

    2012-06-01

    Borrelia burgdorferi, the causative agent of Lyme disease, exists in nature through a complex life cycle involving ticks of the Ixodes genus and mammalian hosts. During its life cycle, B. burgdorferi experiences fluctuations in oxygen tension and may encounter reactive oxygen species (ROS). The key metalloenzyme to degrade ROS in B. burgdorferi is SodA. Although previous work suggests that B. burgdorferi SodA is an iron-dependent superoxide dismutase (SOD), later work demonstrates that B. burgdorferi is unable to transport iron and contains an extremely low intracellular concentration of iron. Consequently, the metal cofactor for SodA has been postulated to be manganese. However, experimental evidence to support this hypothesis remains lacking. In this study, we provide biochemical and genetic data showing that SodA is a manganese-dependent enzyme. First, B. burgdorferi contained SOD activity that is resistant to H(2)O(2) and NaCN, characteristics associated with Mn-SODs. Second, the addition of manganese to the Chelex-treated BSK-II enhanced SodA expression. Third, disruption of the manganese transporter gene bmtA, which significantly lowers the intracellular manganese, greatly reduced SOD activity and SodA expression, suggesting that manganese regulates the level of SodA. In addition, we show that B. burgdorferi is resistant to streptonigrin, a metal-dependent redox cycling compound that produces ROS, and that SodA plays a protective role against the streptonigrin. Taken together, our data demonstrate the Lyme disease spirochete encodes a manganese-dependent SOD that contributes to B. burgdorferi defense against intracellular superoxide. PMID:22500025

  3. SOLID PHASE SPECIATION OF IRON AND MANGANESE IN ALUM SHALE SOILS STUDIED BY PARALLEL AND SEQUENTIAL EXTRACTION

    Microsoft Academic Search

    R. P. Narwall; B. R. Singh

    2001-01-01

    The kind of association of heavy metals with soil components determines the mobility and availability of metals in soils. It is, therefore, necessary to understand and differentiate the different physicochemical forms of metals. A laboratory study was conducted to investigate the solubility of iron (Fe) and manganese (Mn) and their association with soil components by the newly developed sequential extraction

  4. Arsenic, Iron, Lead, Manganese and Uranium Concentrations in Private Bedrock Wells in Southeastern New Hampshire, 2012-2013

    EPA Science Inventory

    Trace metals, such as arsenic, iron, lead, manganese, and uranium, in groundwater used for drinking have long been a concern because of the potential adverse effects on human health and the aesthetic or nuisance problems that some present. Moderate to high concentrations of the t...

  5. Determination of Microamount of Aluminum, Chromium, Copper, Iron, Manganese, Molybdenum and Nickel in Pure Water by Extraction Photometry

    Microsoft Academic Search

    Kenji MOTOJIMA; Nasumi ISHIWATARI

    1965-01-01

    Aluminum, iron (III), copper, and molybdenum 8-quinolinol complexes, chromium (III) and manganese 8-hydroxyquinaldine complexes and nickel dimethylglyoxime complex can be quantitatively extracted into chloroform from large volumes of aqueous phases adjusted to an approriate pH for each metal. These metals can be determined by measuring the absorbance of the organic phases containing their complexes at an appropriate wavelength for each

  6. Validation of In-Situ Iron-Manganese Oxide Coated Stream Pebbles as Sensors for Arsenic Source Monitoring

    NASA Astrophysics Data System (ADS)

    Blake, J.; Peters, S. C.; Casteel, A.

    2013-12-01

    Locating nonpoint source contaminant fluxes can be challenging due to the inherent heterogeneity of source and of the subsurface. Contaminants such as arsenic are a concern for drinking water quality and ecosystem health. Arsenic contamination can be the result of several natural and anthropogenic sources, and therefore it can be difficult to trace and identify major areas of arsenic in natural systems. Identifying a useful source indicator for arsenic is a crucial step for environmental remediation efforts. Previous studies have found iron-manganese oxide coated streambed pebbles as useful source indicators due to their high attraction for heavy metals in water. In this study, pebbles, surface water at baseflow and nearby rocks were sampled from the Pennypack Creek and its tributaries, in southwestern Pennsylvania, to test the ability of coated streambed pebbles as environmental source indicators for arsenic. Quartz pebbles, 5-7 cm in diameter, were sampled to minimize elemental contamination from rock chemistry. In addition, quartz provides an excellent substrate for iron and manganese coatings to form. These coatings were leached from pebbles using 4M nitric acid with 0.1% concentrated hydrochloric acid. Following sample processing, analyses were performed using an ICP-MS and the resulting data were spatially organized using ArcGIS software. Arsenic, iron and manganese concentrations in the leachate are normalized to pebble surface area and each location is reported as a ratio of arsenic to iron and manganese. Results suggest that iron-manganese coated stream pebbles are useful indicators of arsenic location within a watershed.

  7. Sources and leaching of manganese and iron in the Saigon River Basin, Vietnam.

    PubMed

    Ha, Nguyen Thi Van; Takizawa, Satoshi; Oguma, Kumiko; Phuoc, Nguyen Van

    2011-01-01

    High concentrations of manganese and iron in the Saigon River are major problems for the water supply in Ho Chi Minh City (HCMC), Viet Nam. To identify their sources and leaching processes, we surveyed water quality along the Saigon River and ran batch leaching tests using soil and sediment samples. Two important leaching processes were identified: acidic leaching from acid sulfate soil (ASS) in the middle reaches of the river, and Mn dissolution and Fe reduction from sediments in the downstream reaches. Low pH caused the concurrent release of Fe and Mn from the ASS. In contrast, anoxia caused the release of Fe but not Mn from the sediments, whereas low pH facilitated Mn dissolution. Sediments are a more important source of Mn because of their higher Mn contents (10 times) and release rates (14 times) than those from ASS. PMID:21977643

  8. The relationship between body iron stores and blood and urine cadmium concentrations in US never-smoking, non-pregnant women aged 20-49 years

    SciTech Connect

    Gallagher, Carolyn M., E-mail: 2crgallagher@optonline.net [PhD Program in Population Health and Clinical Outcomes Research, Stony Brook University, NY (United States) and Department of Preventive Medicine, Stony Brook University, Z-8036, Level 3, HSC, Stony Brook, NY 11794-8036 (United States); Chen, John J.; Kovach, John S. [Department of Preventive Medicine, Stony Brook University, Z-8036, Level 3, HSC, Stony Brook, NY 11794-8036 (United States)] [Department of Preventive Medicine, Stony Brook University, Z-8036, Level 3, HSC, Stony Brook, NY 11794-8036 (United States)

    2011-07-15

    Background: Cadmium is a ubiquitous environmental pollutant associated with increased risk of leading causes of mortality and morbidity in women, including breast cancer and osteoporosis. Iron deficiency increases absorption of dietary cadmium, rendering women, who tend to have lower iron stores than men, more susceptible to cadmium uptake. We used body iron, a measure that incorporates both serum ferritin and soluble transferrin receptor, as recommended by the World Health Organization, to evaluate the relationships between iron status and urine and blood cadmium. Methods: Serum ferritin, soluble transferrin receptor, urine and blood cadmium values in never-smoking, non-pregnant, non-lactating, non-menopausal women aged 20-49 years (n=599) were obtained from the 2003-2008 National Health and Nutrition Examination Surveys. Body iron was calculated from serum ferritin and soluble transferrin receptor, and iron deficiency defined as body iron <0 mg/kg. Robust linear regression was used to evaluate the relationships between body iron and blood and urine cadmium, adjusted for age, race, poverty, body mass index, and parity. Results: Per incremental (mg/kg) increase in body iron, urine cadmium decreased by 0.003 {mu}g/g creatinine and blood cadmium decreased by 0.014 {mu}g/L. Iron deficiency was associated with 0.044 {mu}g/g creatinine greater urine cadmium (95% CI=0.020, 0.069) and 0.162 {mu}g/L greater blood cadmium (95% CI=0.132, 0.193). Conclusions: Iron deficiency is a risk factor for increased blood and urine cadmium among never-smoking, pre-menopausal, non-pregnant US women, independent of age, race, poverty, body mass index and parity. Expanding programs to detect and correct iron deficiency among non-pregnant women merits consideration as a potential means to reduce the risk of cadmium associated diseases. - Highlights: {yields} Body iron was calculated from serum ferritin and soluble transferrin receptor. {yields} Body iron was inversely associated with blood and urine cadmium in US women. {yields} Inverse associations with blood cadmium were evident in all race/ethnic subsamples. {yields} Inverse associations with urine cadmium were evident in women of other/multi-race. {yields} Black women had lower mean body iron compared to white women.

  9. Adsorption of copper, cadmium, lead and zinc onto a synthetic manganese oxide.

    PubMed

    Della Puppa, Loïc; Komárek, Michael; Bordas, François; Bollinger, Jean-Claude; Joussein, Emmanuel

    2013-06-01

    Due to its simple and inexpensive synthesis, a new amorphous hydrous manganese oxide (AMO) has been studied as a possible chemical stabilizing agent for soils contaminated with metals. Preliminary experiments evaluating the stability of AMO in pure water have reported only minor dissolution (5.70% and 0.24% depending on the w/v ratio). Sorption kinetics have shown fast metal adsorption, especially for Pb. The sorption capacities of AMO for Cu, Cd, Pb, and Zn have been described and compared with synthetic birnessite for pH 4 and 5.5. Both oxides show similar sorption capacities at pH 4 despite the fact that birnessite characteristics (pH of zero point charge, specific surface area and cation exchange capacity) are more favorable for metal sorption. Moreover, the pH adsorption-edges show that the AMO is more pH-dependent than birnessite. PMID:23566588

  10. Relationships between chemical forms of soil iron and manganese and their absorption by rice from 34 flooded Gulf Coast soils of Texas

    E-print Network

    Phillips, Douglas Patton

    1971-01-01

    plant uptake. The determina- tions of exchangeable iron and manganese will provide a reference with which to compare the water soluble or easily reducible forms. Changes in the reduction potentials of these soils with submergence along...

  11. Metallation and mismetallation of iron and manganese proteins in vitro and in vivo: the class I ribonucleotide reductases as a case study

    E-print Network

    Stubbe, JoAnne

    How cells ensure correct metallation of a given protein and whether a degree of promiscuity in metal binding has evolved are largely unanswered questions. In a classic case, iron- and manganese-dependent superoxide dismutases ...

  12. Mesoporous iron–manganese oxides for sulphur mustard and soman degradation

    SciTech Connect

    Štengl, Václav, E-mail: stengl@iic.cas.cz [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR, v.v.i., 250 68 ?ež (Czech Republic) [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR, v.v.i., 250 68 ?ež (Czech Republic); J.E. Purkyn? University in Ústí nad Labem, Faculty of Environment, 400 96 Ústí nad Labem (Czech Republic); Grygar, TomᚠMatys [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR, v.v.i., 250 68 ?ež (Czech Republic) [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR, v.v.i., 250 68 ?ež (Czech Republic); J.E. Purkyn? University in Ústí nad Labem, Faculty of Environment, 400 96 Ústí nad Labem (Czech Republic); Bludská, Jana [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR, v.v.i., 250 68 ?ež (Czech Republic)] [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR, v.v.i., 250 68 ?ež (Czech Republic); Opluštil, František; N?mec, Tomᚠ[Military Technical Institute of Protection Brno, Vesla?ská 230, 628 00 Brno (Czech Republic)] [Military Technical Institute of Protection Brno, Vesla?ská 230, 628 00 Brno (Czech Republic)

    2012-12-15

    Graphical abstract: Display Omitted Highlights: ? New nanodispersive materials based on Fe and Mn oxides for degradations of warfare agents. ? The best activities for the degradation of sulphur mustard (97.9% in 64 min) and soman (97.9% in 64 min). ? One pot synthesis with friendly transformed to industrial conditions. -- Abstract: Substituted iron(III)–manganese(III, IV) oxides, ammonio-jarosite and birnessite, were prepared by a homogeneous hydrolysis of potassium permanganate and iron(III) sulphate with 2-chloroacetamide and urea, respectively. Synthesised oxides were characterised using Brunauer–Emmett–Teller (BET) surface area and Barrett–Joiner–Halenda porosity (BJH), X-ray diffraction (XRD), infrared spectroscopy (IR), Raman spectroscopy and scanning electron microscopy (SEM). The oxides were taken for an experimental evaluation of their reactivity against sulphur mustard (HD) and soman (GD). When ammonio-jarosite formation is suppressed by adding urea to the reaction mixture, the reaction products are mixtures of goethite, schwertmannite and ferrihydrite, and their degradation activity against soman considerably increases. The best activities for the degradation of sulphur mustard (97.9% in 64 min) and soman (97.9% in 64 min) were observed for FeMn{sub 7}5 with 32.6 wt.% Fe (36.8 wt.% Mn) and FeMn{sub 3}7U with 60.8 wt.% Fe (10.1 wt.% Mn) samples, respectively.

  13. Metals, Oxidative Stress and Neurodegeneration: A focus on Iron, Manganese and Mercury

    PubMed Central

    Farina, Marcelo; Avila, Daiana Silva; da Rocha, João Batista Teixeira

    2013-01-01

    Essential metals are crucial for the maintenance of cell homeostasis. Among the 23 elements that have known physiological functions in humans, 12 are metals, including iron (Fe) and manganese (Mn). Nevertheless, excessive exposure to these metals may lead to pathological conditions, including neurodegeneration. Similarly, exposure to metals that do not have known biological functions, such as mercury (Hg), also present great health concerns. This reviews focuses on the neurodegenerative mechanisms and effects of Fe, Mn and Hg. Oxidative stress (OS), particularly in mitochondria, is a common feature of Fe, Mn and Hg toxicity. However, the primary molecular targets triggering OS are distinct. Free cationic iron is a potent pro-oxidant and can initiate a set of reactions that form extremely reactive products, such as OH•. Mn can oxidize dopamine (DA), generating reactive species and also affect mitochondrial function, leading to accumulation of metabolites and culminating with OS. Cationic Hg forms have strong affinity for nucleophiles, such as –SH and –SeH. Therefore, they target critical thiol- and selenol-molecules with antioxidant properties. Finally, we address the main sources of exposure to these metals, their transport mechanisms into the brain, and therapeutic modalities to mitigate their neurotoxic effects. PMID:23266600

  14. The distribution of copper, manganese, zinc, and iron in antarctic waters and the relation of the concentrations of these metals to biological primary productivity

    E-print Network

    Arhelger, Martin Edward

    1967-01-01

    THE DISTRIBUTION OF COPPER, MANGANESE, ZINC, AND IRON IN ANTARCTIC WATERS AND THE RELATION OF THE CONCENTRATIONS OF THESE METALS TO BIOLOGICAL PRIMARY PRODUCTIVITY A Thesis By MARTIN EDWARD ARHELGER Submitted to the Graduate College... of the Texas A& 1 University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August I967 Major Subj ect: CHEMICAL OCEANOGRAPHY THE DISTRIBUTION OF COPPER, MANGANESE, ZINC, AND IRON IN ANTARCTIC WATERS AND THE RELATION...

  15. Liver and kidney concentrations of strontium, barium, cadmium, copper, zinc, manganese, chromium, antimony, selenium and lead in cats

    PubMed Central

    2014-01-01

    Background In order to provide new knowledge on the storage of strontium (Sr), barium (Ba), cadmium (Cd), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), antimony (Sb), selenium (Se) and lead (Pb) in the feline organism, we measured the concentrations of these elements in the liver, renal cortex and renal medulla, evaluating also the impact of age, sex or the occurrence of a chronic kidney disease (CKD). The element concentrations in the tissues of 47 cats (22 male; 25 female; aged between 2 months and 18 years) were measured using inductively coupled plasma mass spectrometry. Results Cu, Zn and Mn were the highest in the liver, followed by the renal cortex and the renal medulla. The Cd concentrations were lower in the renal medulla compared to the renal cortex and the liver, and Sr was higher in the renal medulla compared to the liver. The Se concentrations in the cortex of the kidneys were higher than in the medulla of the kidneys and in the liver. Higher Cd concentrations were measured in the renal cortex of female cats, while no further gender-related differences were observed. Except for Cr, Sb and Se, age-dependencies were detected for the storage of all elements. The occurrence of a CKD also affected the storage of the elements, with lower concentrations of Ba (renal medulla), Zn (renal cortex; renal medulla) and Mn (liver; renal medulla), but higher Cd concentrations (liver; renal cortex) in diseased cats. Conclusions In conclusion, the present results provide new information on the accumulation of specific elements in the feline liver and kidneys, demonstrating a dependency on age and an impaired kidney function, but not on the sex of the animals. PMID:25030305

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

    PubMed

    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. PMID:25061551

  17. Interaction between anemia and blood levels of iron, zinc, copper, cadmium and lead in children

    Microsoft Academic Search

    Sebahat Turgut; Aziz Polat; Murat Inan; Günfer Turgut; Gülten Emmungil; Mevlüt Bican; Tugrul Yasin Karakus; Osman Genç

    2007-01-01

    Objective  Anemia is a widespread problem among infants and children in many parts of the world, and it is often associated with some\\u000a trace elements (iron, zinc, copper) and heavy metals (cadmium and lead). Aim of this study was to investigate the relationship\\u000a between anemia and these elements.\\u000a \\u000a \\u000a \\u000a Methods  This research was performed on 256 children (mean age 6.8 ± 0.2) living

  18. Impact of orchard and tillage management practices on soil leaching of atrazine, potassium, magnesium, manganese, iron, ammonium, nitrates and phosphates

    Microsoft Academic Search

    L. Szajdak; J. Lipiec; A. Siczek; U. Kotowska; A. Nosalewicz

    2009-01-01

    The experiments were carried out on an Orthic Luvisol developed from loess, over limestone, at the experimental field of Lublin Agricultural University in Felin (51o15'N, 22o35'E), Poland. The investigation deals with the problems of leaching's rate of atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,2,3-triazine), potassium, magnesium, manganese, iron, ammonium, nitrates and phosphates from two management systems of soil: (i) conventionally tilled field with main tillage

  19. Evaluation of iron and manganese-coated pumice application for the removal of as(v) from aqueous solutions.

    PubMed

    Far, Leila Babaie; Souri, Bubak; Heidari, Masoumeh; Khoshnavazi, Roshan

    2012-01-01

    Arsenic contamination of water has been recognized as a serious environmental issue and there are reports on its epidemiological problems to human health. The objective of this study was to evaluate the performances of iron-coated pumice and manganese-coated pumice as the adsorbents for removing arsenate from aqueous solutions. The effect of various parameters such as adsorbent dose, contact time, pH and initial concentration on removal efficiency of arsenate were evaluated in batch mode. The data obtained from the kinetic studies were analyzed using kinetic models of pseudo-first-order and pseudo-second-order. In addition, two isotherm models of Freundlich and Langmuir were used to fit the experimental data. The results showed that the optimum dosage of iron-coated pumice and manganese-coated pumice for arsenate removal were 40 and 80 g/L whereas the adsorption process reached equilibrium after 80 and 100 min, respectively. The maximum removal efficiency of arsenate using the two adsorbents were both recorded in pH=3 as the removal efficiency gradually declined following every increase in pH values of the solution. Iron-coated pumice also showed to have high removal efficiency when the initial concentration of arsenate was high while the low concentration of arsenate was efficiently removed by manganese-coated pumice. Moreover, it was depicted that the adsorption kinetics by both adsorbents followed pseudo-second order equation and the uptake data of arsenate were well fitted with Langmuir isotherm model. Therefore, it could be concluded that iron and manganese-coated pumice could be considered as suitable adsorbents for arsenate removal from aqueous solutions. PMID:23369510

  20. Studies on the role of iron in the reversal of cadmium toxicity in chicks.

    PubMed

    Blalock, T L; Hill, C H

    1988-01-01

    Studies were conducted to determine the effect of dietary iron (Fe) levels ranging from a deficiency to an excess on the toxicity of cadmium (Cd) in chicks. In Fe-deficient animals, cadmium was found to be more toxic than in Fe supplemented animals as measured by growth. The liver Cd burdens were increased significantly in the presence of dietary Fe supplementation, and there was a significant Cd-Fe interaction in the Cd concentration of the kidney, indicating that iron deficiency increased the concentration of Cd in the kidneys of those chicks receiving this element. Cd tended to reduce the Fe concentration in both the liver and kidney. The absorption of Cd as measured by the amount of 109Cd that disappeared from an isolated duodenal segment in one h was not affected by the Fe content of the diet, but the amount of isotope appearing in the liver compared to the amount present in the blood was increased in the Fe supplemented chicks. Separation of the Cd binding ligands by column chromatography revealed that more of the Cd in the liver, but not the kidney, was associated with ligands which eluted in a column volume that contained metallothionein in those chicks receiving Fe than in the livers from Fe deficient animals. The inverse relationship between the amount of Cd bound to the metallothionein containing fraction and toxicity may be related causally. PMID:2484363

  1. Dietary iron lowers the intestinal uptake of cadmium-metallothionein in rats.

    PubMed

    Groten, J P; Luten, J B; van Bladeren, P J

    1992-05-01

    It has been shown that addition of extra calcium/phosphorus (Ca/P), zinc (Zn) and iron (Fe2+) to the diet results in a significant protection against cadmium (Cd) accumulation and toxicity in rats fed inorganic Cd salt. However, it is not clear whether the presence of these mineral supplements in the diet also protects against the Cd uptake from cadmium-metallothionein. The present study examines the influence of Ca/P, Zn and Fe2+ on the Cd disposition in rats fed diets containing either 1.5 and 8 mg Cd/kg diet as cadmium-metallothionein (CdMt) or as cadmium chloride (CdCl2) for 4 weeks. The feeding of Cd resulted in a dose-dependent increase of Cd in intestine, liver and kidneys. The total Cd uptake in liver and kidneys after exposure to CdMt was lower than after exposure to CdCl2. At the low dietary Cd level and after addition of the mineral supplement, the kidney/liver concentration ratio increased. However, this ratio was always higher with CdMt than with CdCl2, suggesting a selective renal disposition of dietary CdMt. The uptake of Cd from CdCl2 as well as from CdMt was significantly decreased by the presence of a combined mineral supplement of Ca/P, Zn and Fe2+. The protection which could be achieved was 72 and 75% for CdMt and 85 and 92% for CdCl2 after doses of 1.5 mg/kg and 8 mg/kg respectively. In a following experiment it was shown that the protective effect of the mineral mixture against CdMt was mainly due to the presence of Fe2+. It seems clear that Cd speciation and the mineral status of the diet have a considerable impact on the extent of Cd uptake in rats. PMID:1397065

  2. Early diagenetic processes generate iron and manganese oxide layers in the sediments of Lake Baikal, Siberia.

    PubMed

    Torres, Natascha T; Och, Lawrence M; Hauser, Peter C; Furrer, Gerhard; Brandl, Helmut; Vologina, Elena; Sturm, Michael; Bürgmann, Helmut; Müller, Beat

    2014-04-01

    Distinct layers of iron(III) and manganese(IV) (Fe/Mn) oxides are found buried within the reducing part of the sediments in Lake Baikal and cause considerable complexity and steep vertical gradients with respect to the redox sequence. For the on-site investigation of the responsible biogeochemical processes, we applied filter tube samplers for the extraction of sediment porewater combined with a portable capillary electrophoresis instrument for the analyses of inorganic cations and anions. On the basis of the new results, the sequence of diagenetic processes leading to the formation, transformation, and dissolution of the Fe/Mn layers was investigated. With two exemplary cores we demonstrate that the dissolution of particulate Fe and Mn is coupled to the anaerobic oxidation of CH? (AOM) either via the reduction of sulphate (SO?(2-)) and the subsequent generation of Fe(II) by S(-II) oxidation, or directly coupled to Fe reduction. Dissolved Fe(II) diffuses upwards to reduce particulate Mn(IV) thus forming a sharp mineral boundary. An alternative dissolution pathway is indicated by the occurrence of anaerobic nitrification of NH?(+) observed at locations with Mn(IV). Furthermore, the reasons and consequences of the non-steady-state sediment pattern and the resulting redox discontinuities are discussed and a suggestion for the burial of active Fe/Mn layers is presented. PMID:24619231

  3. Aluminium, iron and manganese in near-surface waters of a tropical rainforest ecosystem.

    PubMed

    Lorieri, D; Elsenbeer, H

    1997-10-01

    A hydrochemical investigation was undertaken in a tropical rainforest catchment to determine the aluminium, iron, and manganese concentrations in near-surface waters of a non-impacted, circum-neutral environment, with an emphasis on hydrologic controls of Al, Fe, and Mn stormflow variations. The concentrations of all three solutes increase with discharge, with antecedent moisture conditions influencing the amplitude. This increase is accompanied by a minor pH depression from about 7.3 to 6.8, and, in the case of one event, by an increase in DOC. For all three solutes, the ranges in stormflow and overland flow concentrations are nearly identical. Al, Fe, and Mn concentrations in soil and ground water are considerably lower, with the exception of Mn in shallow soil water which is similar to overland flow. We conclude that episodic increases in streamflow metal concentrations in this tropical rainforest environment are not so much the result of a pronounced pH depression, but of an overland flow-mediated input from near-surface sources such as leaf litter and topsoil. PMID:9352668

  4. Molecular-Level Processes Governing the Interaction of Contaminants with Iron and Manganese Oxides - Final Report

    SciTech Connect

    Brown Jr., G. E.; Chambers, S. A.

    1999-10-31

    Many of the inorganic and organic contaminants present in sediments at DOE sites can be altered or destroyed by reduction and oxidation (redox) reactions occurring at mineral surfaces. A fundamental understanding of such redox processes provided by molecular-level studies on structurally and compositionally well-defined mineral surfaces will lead to: (i) improved models of contaminant fate and transport in geochemical systems, and (ii) optimized manipulation of these processes for remediation purposes. To contribute to this understanding, we will study, both experimentally and theoretically, redox processes involving three important contaminants - chromate ion, carbon tetrachloride, and trichloroethene TCE, on the following iron and manganese oxides - hematite, magnetite, maghemite, and pyrolusite. These oxides and their hydroxylated analogs commonly occur as coatings on minerals or as interfaces in the subsurface environment. Single-crystal surfaces of these oxides will be synthesized in carefully controlled fashion by molecular beam epitaxy. These surfaces, as well as high surface are powdered samples of these oxides, will be used in spectroscopic and kinetic experiments in both aqueous and gas phases. Our goal is to identify products and to determine the kinetics and mechanisms of surface-catalyzed redox reaction of Cr(VI) and CR(III), and the reductive dechlorination of carbon tetrachloride and TCE. The combination of theory and experiment will provide the base information needed to scale from the molecular level to the microscopic grain level minerals.

  5. Functional differences between manganese and iron superoxide dismutases in Escherichia coli K-12.

    PubMed

    Hopkin, K A; Papazian, M A; Steinman, H M

    1992-12-01

    Superoxide dismutases are enzymes that defend against oxidative stress through decomposition of superoxide radical. Escherichia coli contains two highly homologous superoxide dismutases, one containing manganese (MnSOD) and the other iron (FeSOD). Although E. coli Mn and FeSOD catalyze the dismutation of superoxide with comparable rate constants, it is not known if they are physiologically equivalent in their protection of cellular targets from oxyradical damage. To address this issue, isogenic strains of E. coli containing either Mn or FeSOD encoded on a plasmid and under the control of tac promoter were constructed. SOD specific activity in the Mn and FeSOD strains could be controlled by the concentration of isopropyl beta-thiogalactoside in the medium. The tolerance of these strains to oxidative stress was compared at equal Mn and FeSOD specific activities. Our results indicate that E. coli Mn and FeSOD are not functionally equivalent. The MnSOD is more effective than FeSOD in preventing damage to DNA, while the FeSOD appears to be more effective in protecting a cytoplasmic superoxide-sensitive enzyme. These data are the first demonstration that Mn and FeSOD are adapted to different antioxidant roles in E. coli. PMID:1447175

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

    PubMed Central

    Kazantzis, G

    1981-01-01

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

  7. Arsenic transport and partitioning within manganese- and iron-oxide rich aggregated sediments

    NASA Astrophysics Data System (ADS)

    Ying, S. C.; Masue-Slowey, Y.; Fendorf, S. E.

    2009-12-01

    Manganese and iron oxides are ubiquitous phases in terrestrial environments that have high sorptive capacities for arsenic. Although numerous studies have characterized the effects of As adsorption onto Fe and Mn oxides individually, the fate of arsenic within mixed (competitive) systems representative of natural environments is unresolved. Here, we investigate As dynamics in an aerobic aggregate composed of ferrihydrite and birnessite coated quartz sand fused by an agarose polymer. Mn and Fe oxide coated sands, having pre-adsorbed As(V), are cast into cohesive spheres and inoculated with Shewanella sp. ANA-3, a bacterial strain capable of reducing As(V) and Mn(IV) and Fe(III) oxides. Arsenic(III) produced by bacterial reduction of As(V) within the aggregate diffuses to the aggregate exterior (proximal to aerated solutes), where it is re-oxidized to As(V) by Mn-oxides; following oxidation, As(V) is repartitioned onto the Fe oxides. X-ray fluorescence microprobe analysis was used to map the spatial distribution of As(III) and As(V) within the aggregate, after which ?-XANES was used to confirm arsenic oxidation state within the mapped areas. These results illustrate the dynamic interplay of biogeochemical transformation, physical heterogeneity, and mixed mineralogy representative of field systems on the fate of arsenic.

  8. Geometric and Electronic Structures of Manganese-substituted Iron Superoxide Dismutase

    PubMed Central

    Jackson, Timothy A.; Gutman, Craig T.; Maliekal, James; Miller, Anne-Frances; Brunold, Thomas C.

    2013-01-01

    The active-site structures of the oxidized and reduced forms of manganese-substituted iron superoxide dismutase (Mn(Fe)SOD) are examined, for the first time, using a combination of spectroscopic and computational methods. On the basis of electronic absorption, circular dichrosim (CD), magnetic CD (MCD), and variable-temperature variable-field MCD data obtained for oxidized Mn(Fe)SOD, we propose that the active site of this species is virtually identical to that of wild-type manganese SOD (MnSOD), both containing a metal ion that resides in a trigonal bipyramidal ligand environment. This proposal is corroborated by quantum mechanical / molecular mechanical (QM/MM) computations performed on complete protein models of Mn(Fe)SOD in both its oxidized and reduced states and, for comparison, wild-type (WT) MnSOD. The major differences between the QM/MM optimized active sites of WT MnSOD and Mn(Fe)SOD are a smaller (His)N–Mn–N(His) equatorial angle and a longer (Gln146(69))NH?O(sol) H-bond distance in the metal-substituted protein. Importantly, these modest geometric differences are consistent with our spectroscopic data obtained for the oxidized proteins and high-field electron paramagnetic resonance spectra reported previously for reduced Mn(Fe)SOD and MnSOD. As Mn(Fe)SOD exhibits a reduction midpoint potential (Em) almost 700 mV higher than that of MnSOD, which has been shown to be sufficient for explaining the lack of SOD activity displayed by the metal-subtituted species (Vance, C. K.; Miller, A. F. Biochemistry 2001, 40, 13079–13087), Ems were computed for our experimentally validated QM/MM optimized models of Mn(Fe)SOD and MnSOD. These computations properly reproduce the experimental trend and reveal that the drastically elevated Em of the metal substituted protein stems from a larger separation between the second-sphere Gln residue and the coordinated solvent in Mn(Fe)SOD relative to MnSOD, which causes a weakening of the corresponding H-bond interaction in the oxidized state and alleviates steric crowding in the reduced state. PMID:23461587

  9. Zinc, lead and cadmium accumulation and tolerance in Typha latifolia as affected by iron plaque on the root surface

    Microsoft Academic Search

    Zhihong Ye; Alan J. M Baker; Ming-Hung Wong; Arthur J Willis

    1998-01-01

    The effects of iron plaque on the growth of Typha latifolia L. and its accumulation of zinc (Zn), lead (Pb) and cadmium (Cd) were investigated under field conditions and in nutrient solution cultures in the laboratory. In the field, Zn concentrations (but not Cd) on the root surface were positively related to Fe concentrations on the root surface. In the

  10. Cadmium Manganese Telluride (Cd1-xMnxTe): A potential material for room-temperature radiation detectors

    SciTech Connect

    Hossain, A.; Cui, Y.; Bolotnikov, A.; Camarda, G.; Yang, G.; Kim, K-H.; Gul, R.; Xu, L.; Li, L.; Mycielski, A.; and James, R.B.

    2010-07-11

    Cadmium Manganese Telluride (CdMnTe) recently emerged as a promising material for room-temperature X- and gamma-ray detectors. It offers several potential advantages over CdZnTe. Among them is its optimal tunable band gap ranging from 1.7-2.2 eV, and its relatively low (< 50%) content of Mn compared to that of Zn in CdZnTe that assures this favorable band-gap range. Another important asset is the segregation coefficient of Mn in CdTe that is approximately unity compared to 1.35 for Zn in CdZnTe, so ensuring the homogenous distribution of Mn throughout the ingot; hence, a large-volume stoichiometric yield is attained. However, some materials issues primarily related to the growth process impede the production of large, defect-free single crystals. The high bond-ionicity of CdMnTe entails a higher propensity to crystallize into a hexagonal structure rather than to adopt the expected zinc-blend structure, which is likely to generate twins in the crystals. In addition, bulk defects generate in the as-grown crystals due to the dearth of high-purity Mn, which yields a low-resistivity material. In this presentation, we report on our observations of such material defects in current CdMnTe materials, and our evaluation of its potential as an alternative detector material to the well-known CdZnTe detectors. We characterized the bulk defects of several indium- and vanadium-doped Cd1-xMnxTe crystals by using several advanced techniques, viz., micro-scale mapping, white-beam x-ray diffraction/reflection topography, and chemical etching. Thereafter, we fabricated some detectors from selected CdMnTe crystals, characterized their electrical properties, and tested their performance as room-temperature X- and gamma-ray detectors. Our experimental results indicate that CdMnTe materials could well prove to become a viable alternative in the near future.

  11. Iron and manganese speciation and cycling in glacially influenced high-latitude fjord sediments (West Spitsbergen, Svalbard): Evidence for a benthic recycling-transport mechanism

    NASA Astrophysics Data System (ADS)

    Wehrmann, Laura M.; Formolo, Michael J.; Owens, Jeremy D.; Raiswell, Robert; Ferdelman, Timothy G.; Riedinger, Natascha; Lyons, Timothy W.

    2014-09-01

    Glacial environments may provide an important but poorly constrained source of potentially bioavailable iron and manganese phases to the coastal ocean in high-latitude regions. Little is known about the fate and biogeochemical cycling of glacially derived iron and manganese in the coastal marine realm. Sediment and porewater samples were collected along transects from the fjord mouths to the tidewater glaciers at the fjord heads in Smeerenburgfjorden, Kongsfjorden, and Van Keulenfjorden along Western Svalbard. Solid-phase iron and manganese speciation, determined by sequential chemical extraction, could be linked to the compositions of the local bedrock and hydrological/weathering conditions below the local glaciers. The concentration and sulfur isotope composition of chromium reducible sulfur (CRS) in Kongs- and Van Keulenfjorden sediments largely reflect the delivery rate and isotope composition of detrital pyrite originating from adjacent glaciers. The varying input of reducible iron and manganese oxide phases and the input of organic matter of varying reactivity control the pathways of organic carbon mineralization in the sediments of the three fjords. High reducible iron and manganese oxide concentrations and elevated metal accumulation rates coupled to low input of “fresh” organic matter lead to a strong expression of dissimilatory metal oxide reduction evidenced in very high porewater iron (up to 800 ?M) and manganese (up to 210 ?M) concentrations in Kongsfjorden and Van Keulenfjorden. Sediment reworking by the benthic macrofauna and physical sediment resuspension via iceberg calving may be additional factors that promote extensive benthic iron and manganese cycling in these fjords. On-going benthic recycling of glacially derived dissolved iron into overlying seawater, where partial re-oxidation and deposition occurs, facilitates the transport of iron across the fjords and potentially into adjacent continental shelf waters. Such iron-dominated fjord sediments are likely to provide significant fluxes of potentially bioavailable iron to coastal waters and beyond. By contrast, low delivery of reducible iron (oxyhydr)oxide phases and elevated organic carbon mineralization rates driven by elevated input of “fresh” marine organic matter allow organoclastic sulfate reduction to dominate carbon remineralization at the outer Smeerenburgfjorden sites, which may limit iron fluxes to the water column.

  12. Single, binary, and multicomponent sorption of iron and manganese on lignite

    SciTech Connect

    Mohad, D.; Chander, S. [Penn State University, University Park, PA (United States). Dept. of Energy & Geoenvironmental Engineering

    2006-07-01

    Acid mine drainage (AMD) has long been a significant environmental problem resulting from the microbial oxidation of iron pyrite in the presence of water and air, affording an acidic solution that contains toxic metal ions. The main objective of this study was to remove metal ions (Fe(II), Fe(III), Mn(II), Zn(II)) from AMD using lignite, a low-cost adsorbent. The lignite sorbent was utilized for the sorption of ferrous, ferric, manganese, zinc, and calcium ions in aqueous solutions. Studies were performed at different pH to find optimum pH. Equilibrium isotherms were determined to assess the maximum adsorption capacity of lignite for different metal ions. Sorption capacities were compared in single, binary, ternary, and multicomponent systems. The sorption data are correlated with Freundlich and Langmuir isotherms in each system. Both Freundlich and Langmuir isotherms fit the data reasonably well in terms of regression coefficients. Sorption studies were also performed at different temperatures to obtain the thermodynamic parameters of the process. The maximum lignite adsorption capacities at 25{sup o}C were 34.22, 25.84, and 11.90 mg/g for Fe(II), Mn(II), and Fe(III), respectively. Adsorption of Fe{sup 2+} (24.70 mg/g at 10{sup o}C and 46.46 mg/g at 40{sup o}C) increased with increased temperature, while Mn{sup 2+} adsorption (28.11 mg/g at 10{sup o}C and 7.70 mg/g at 40{sup o}C) decreased with increased temperature.

  13. Substitution of manganese and iron into hydroxyapatite: Core/shell nanoparticles

    SciTech Connect

    Pon-On, Weeraphat; Meejoo, Siwaporn [Department of Chemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Tang, I.-Ming [Department of Physics, Faculty of Science, Mahidol University, Institute of Science and Technology for Research and Development, Salaya Campus, Mahidol University, Nakorn Pathom 71730 (Thailand)], E-mail: scimt@mahidol.ac.th

    2008-08-04

    The bioceramics, hydroxyapatite (HAP), is a material which is biocompatible to the human body and is well suited to be used in hyperthermia applications for the treatment of bone cancer. We investigate the substitution of iron and manganese into the hydroxyapatite to yield ceramics having the empirical formula Ca{sub 9.4}Fe{sub 0.4}Mn{sub 0.2}(PO{sub 4}){sub 6}(OH){sub 2}. The samples were prepared by the co-precipitation method. The formation of the nanocrystallites in the HAP structure as the heating temperatures were raised to obtain a glass-ceramic system are confirmed by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron diffraction (ED) and electron spin resonance (ESR). TEM images show the core/shell structure of the nanoparticles, with the core being formed by the ferrites and the shell by the hydroxyapatite. The ED patterns indicate the nanoparticles formed at 500 deg. C have an amorphous structure while the nanoparticles formed at 1000 deg. C are crystalline. ESR spectroscopy indicated that the Fe{sup 3+} ions have a g-factor of 4.23 and the Mn{sup 2+} ions have a g-factor of 2.01. The values of the parameters in the spin Hamiltonian which describes the interaction between the transition metal ions and the Ca{sup 2+} ions, indicate that the Mn{sup 2+} ion substitute into the Ca{sup 2+} sites which are ninefold coordinated, i.e., the Ca(1) sites.

  14. Influence of organic matter on the uptake of cadmium, zinc, copper and iron by sorghum plants.

    PubMed

    Pinto, A P; Mota, A M; de Varennes, A; Pinto, F C

    2004-06-29

    This article describes an experiment, carried out under controlled environment conditions, to investigate the effects of a fulvic acid fraction of soil organic matter on growth, cadmium (Cd) uptake and redistribution by sorghum. In addition the uptake of copper (Cu), zinc (Zn) and iron (Fe) was also determined. Sorghum was grown in nutrient solutions with 0, 0.1, 1 and 10 mg Cd dm(-3), in the absence and presence of organic matter (32 mg C dm(-3)), for various periods up to 20 days. A decrease in sorghum biomass due to Cd toxicity was observed at 10 mg Cd dm(-3), but for concentrations of 0.1 and 1 mg Cd dm(-3) the biomass was increased compared with control, without visual toxicity symptoms. The presence of organic matter (OM) further increased biomass production. Cadmium was mainly retained in sorghum roots, as usually found in tolerant plants, but Cd accumulation in sorghum was greater than in other Gramineae, or even more tolerant plants such as lettuce. The presence of OM decreased the bioavailability of Cd that was partially retained in solution by the OM ligands. However, OM promoted the translocation of Cd to shoots, an effect that may pose a risk to public health because plant-animal transfer of Cd could be enhanced. The presence of OM decreased the uptake of Cu, Zn and Fe. The presence (vs. absence) of 0.1 mg Cd dm(-3) enhanced the uptake of Fe, both in the absence and presence of OM. PMID:15142779

  15. Interactions of cadmium compounds with endogenous iron in the intestinal tract

    SciTech Connect

    Sugawara, N.; Sugawara, C. (Sapporo Medical Coll., Sapporo (Japan))

    1991-02-01

    The authors previously reported that when cadmium (Cd) given orally to mice or rats, they showed a decrease of hemoglobin, or of hepatic and renal iron (Fe). The decrease may be due to the decrease of Fe uptake into the intestinal mucosa brush border membrane. In a related work, it was suggested that internalized-Cd blocks the transferrin cycle within intestinal cells. Recently, the role of ferritin in the process of intestinal Fe absorption has been evaluated. Even now, Fe absorption from the GI tract is still under discussion. In order to understand the competition of Cd with Fe further, the authors gave some Cd compounds known to be taken up in different manners into the intestinal mucosa to mice.

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

    SciTech Connect

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

    1986-04-01

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

  17. Arabidopsis HY1 confers cadmium tolerance by decreasing nitric oxide production and improving iron homeostasis.

    PubMed

    Han, Bin; Yang, Zheng; Xie, Yanjie; Nie, Li; Cui, Jin; Shen, Wenbiao

    2014-02-01

    Up-regulation of the gene that encodes intracellular heme oxygenase 1 (HO1) benefits plants under cadmium (Cd(2+)) stress; however, the molecular mechanisms remain unclear. Here, we elucidate the role of Arabidopsis HY1 (AtHO1) in Cd(2+) tolerance by using genetic and molecular approaches. Analysis of two HY1 null mutants, three HY1 overexpression lines, HO double or triple mutants, as well as phyA and phyB mutants revealed the specific hypersensitivity of hy1 to Cd(2+) stress. Supplementation with two enzymatic by-products of HY1, carbon monoxide (CO) and iron (Fe, especially), rescued the Cd(2+)-induced inhibition of primary root (PR) elongation in hy1-100. The mutation of HY1, which exhibited lower glutathione content than Col-0 in root tissues, was able to induce nitric oxide (NO) overproduction, Cd(2+) accumulation, and severe Fe deficiency in root tissues. However, the contrasting responses appeared in 35S:HY1-4. Additionally, reduced levels of Ferric Reduction Oxidase 2 (FRO2) and Iron-Regulated Transporter 1 (IRT1) transcripts, and increased levels of Heavy Metal ATPase 2/4 (HMA2/4) transcripts bolster the notion that HY1 up-regulation ameliorates Fe deficiency, and might increase Cd(2+) exclusion. Taken together, these results showed that HY1 plays a common link in Cd(2+) tolerance by decreasing NO production and improving Fe homeostasis in Arabidopsis root tissues. PMID:23974911

  18. Effect of hemolytic and iron-deficiency anemia on intestinal absorption and tissue accumulation of cadmium.

    PubMed

    Min, Kyong-Son; Iwata, Naoyuki; Tetsutikawahara, Noriko; Onosaka, Satomi; Tanaka, Keiichi

    2008-06-10

    Abnormal iron (Fe) metabolism induces iron-deficiency anemia (FeDA) and also affects body cadmium (Cd) accumulation. However, whether hemolytic anemia also affects Cd metabolism is not known. We compared the intestinal absorption and tissue accumulation of Cd after oral administration of Cd to mice with hemolytic anemia induced by treatment with phenylhydrazine (PHA mice) to that in mice with FeDA. Although the hematocrit decreased significantly in mice with either type of anemia, the Fe concentration decreased in the livers and kidneys of FeDA mice, but increased in those of PHA mice. After an oral administration with various amounts of Cd, hepatic and renal Cd concentrations significantly increased in both FeDA and PHA mice. An intraduodenal injection of Fe raised the hepatic Fe content in FeDA mice to the control level and raised the hepatic Fe content in PHA mice to 2.4 times that in control mice. Intestinal divalent metal transporter 1 (DMT1) expression increased significantly in mice with both types of anemia. These data indicate that, despite the accumulation of hepatic Fe associated with PHA, PHA also significantly increases hepatic and renal Cd accumulation according to an stimulation of intestinal DMT1 expression, as occurs in FeDA mice. This suggests that anemia may be a risk factor for Cd accumulation. PMID:18485624

  19. Regulation of metal transporters by dietary iron, and the relationship between body iron levels and cadmium uptake.

    PubMed

    Kim, Dong-Won; Kim, Ki-Young; Choi, Byung-Sun; Youn, Pilju; Ryu, Doug-Young; Klaassen, Curtis D; Park, Jung-Duck

    2007-05-01

    Iron (Fe) plays essential roles in biological processes, whereas cadmium (Cd) is a toxic and non-essential metal. Two metal transporters, divalent metal transporter 1 (DMT1) and metal transporter protein 1 (MTP1), are responsible for Fe transport in mammals. Here, we studied the effect of dietary Fe on the expression of these metal transporters in peripheral tissues, and the uptake by these tissues of Cd. Mice were fed an Fe-sufficient (FeS: 120 mg Fe/kg) or Fe-deficient (FeD: 2-6 mg Fe/kg) diet for 4 weeks. The total Fe levels in the body were evaluated by measuring tissue Fe concentrations. Tissue Cd concentrations were determined 24 h after the mice received a single oral dose of Cd. Animals fed a FeD diet showed depletion of body Fe levels and accumulated 2.8-fold higher levels of Cd than the FeS group. Quantitative real time RT-PCR revealed that whereas DMT1 and MTP1 were both ubiquitously expressed in all FeS peripheral tissues studied, DMT1 was highly expressed in brain, kidney, and testis, whereas MTP1 was highly expressed in liver and spleen. Depletion of the body Fe stores dramatically upregulated DMT1 and MTP1 mRNA expression in the duodenum as well as moderately upregulating their expression in several other peripheral tissues. The iron response element positive isoform of DMT1 was the most prominently upregulated isoform in the duodenum. Thus, DMT1 and MTP1 may play an important role in not only maintaining Fe levels but also facilitating the accumulation of Cd in the body of mammals. PMID:17031680

  20. Insights into the iron-ome and manganese-ome of ?mtm1 Saccharomyces cerevisiae Mitochondria

    PubMed Central

    Park, Jinkyu; McCormick, Sean P.; Chakrabarti, Mrinmoy

    2013-01-01

    Biophysical spectroscopies and LC-ICP-MS were used to evaluate the iron-ome and manganese-ome of mitochondria from ?mtm1 yeast cells. Deleting the mitochondrial carrier gene MTM1 causes Fe to accumulate in mitochondria and Mn superoxide dismutase (SOD2) activity to decline. One explanation for this is that some accumulated Fe misincorporates into apo-Sod2p. Mössbauer spectroscopy revealed that most of the accumulated Fe was FeIII nanoparticles which are unlikely to misincorporate into apo-Sod2p. Under anaerobic conditions, Fe did not accumulate yet SOD2 activity remained low, suggesting that the two phenomena are independent. Mn concentrations were two-fold higher in ?mtm1 mitochondria than in WT mitochondria. Soluble extracts from such samples were subjected to size-exclusion LC and fractions were analyzed with an on-line ICP-MS. Two major Mn peaks were observed, one due to MnSod2p and the other to a Mn species with a mass of 2–3 kDa (called Mn2–3). Mn2–3 may deliver Mn into apo-Sod2p. Most Mn in WT mitochondria was associated with MnSod2p, whereas most Mn in ?mtm1 mitochondria was associated with Mn2–3. The [Mn2–3] increased in cells grown on high MnCl2 while the MnSod2p concentration remained unchanged. Corresponding Fe traces showed numerous peaks, including a complex of ~ 3 kDa which may be the form of Fe that misincorporates, and an Fe peak with the molecular mass of Sod2p that may correspond to FeSod2p. The intensity of this peak suggests that deleting MTM1 probably diminishes SOD2 activity by some means other than Fe misincorporation. A portion of Sod2p in ?mtm1 mitochondria might be unfolded or immature. Mtm1p may import a species required for apo-Sod2p maturation, activity or stability. PMID:23598994

  1. Effect of Anions on the Binding and Oxidation of Divalent Manganese and Iron in Modified Bacterial Reaction Centers

    PubMed Central

    Tang, Kai; Williams, JoAnn C.; Allen, James P.; Kálmán, László

    2009-01-01

    Abstract The influence of different anions on the binding and oxidation of manganous and ferrous cations was studied in four mutants of bacterial reaction centers that can bind and oxidize these metal ions. Light-minus-dark difference optical and electron paramagnetic resonance spectroscopies were applied to monitor electron transfer from bound divalent metal ions to the photo-oxidized bacteriochlorophyll dimer in the presence of five different anions. At pH 7, bicarbonate was found to be the most effective for both manganese and iron binding, with dissociation constants around 1 ?M in three of the mutants. The pH dependence of the dissociation constants for manganese revealed that only bicarbonate and acetate were able to facilitate the binding and oxidation of the metal ion between pH 6 and 8 where the tight binding in their absence could not otherwise be established. The data are consistent with two molecules of bicarbonate or one molecule of acetate binding to the metal binding site. For ferrous ion, the binding and oxidation was facilitated not only by bicarbonate and acetate, but also by citrate. Electron paramagnetic resonance spectra suggest differences in the arrangement of the iron ligands in the presence of the various anions. PMID:19383473

  2. Iron, copper, and manganese complexes with in vitro superoxide dismutase and/or catalase activities that keep Saccharomyces cerevisiae cells alive under severe oxidative stress.

    PubMed

    Ribeiro, Thales P; Fernandes, Christiane; Melo, Karen V; Ferreira, Sarah S; Lessa, Josane A; Franco, Roberto W A; Schenk, Gerhard; Pereira, Marcos D; Horn, Adolfo

    2015-03-01

    Due to their aerobic lifestyle, eukaryotic organisms have evolved different strategies to overcome oxidative stress. The recruitment of some specific metalloenzymes such as superoxide dismutases (SODs) and catalases (CATs) is of great importance for eliminating harmful reactive oxygen species (hydrogen peroxide and superoxide anion). Using the ligand HPClNOL {1-[bis(pyridin-2-ylmethyl)amino]-3-chloropropan-2-ol}, we have synthesized three coordination compounds containing iron(III), copper(II), and manganese(II) ions, which are also present in the active site of the above-noted metalloenzymes. These compounds were evaluated as SOD and CAT mimetics. The manganese and iron compounds showed both SOD and CAT activities, while copper showed only SOD activity. The copper and manganese in vitro SOD activities are very similar (IC50~0.4?mol dm(-3)) and about 70-fold higher than those of iron. The manganese compound showed CAT activity higher than that of the iron species. Analyzing their capacity to protect Saccharomyces cerevisiae cells against oxidative stress (H2O2 and the O2(•-) radical), we observed that all compounds act as antioxidants, increasing the resistance of yeast cells mainly due to a reduction of lipid oxidation. Especially for the iron compound, the data indicate complete protection when wild-type cells were exposed to H2O2 or O2(•-) species. Interestingly, these compounds also compensate for both superoxide dismutase and catalase deficiencies; their antioxidant activity is metal ion dependent, in the order iron(III)>copper(II)>manganese(II). The protection mechanism employed by the complexes proved to be independent of the activation of transcription factors (such as Yap1, Hsf1, Msn2/Msn4) and protein synthesis. There is no direct relation between the in vitro and the in vivo antioxidant activities. PMID:25511255

  3. Catalytic kinetic simultaneous determination of iron, silver and manganese with the Kalman filter by using flow injection analysis stopped-flow spectrophotometry

    Microsoft Academic Search

    Ying-Zhi Ye; Hong-Yan Mao; Ya-Hua Chen

    1998-01-01

    A catalytic differential kinetic method with Kalman filter for the simultaneous determination of multi-component is described. The oxidization of Rhodamine B (RB) by potassium periodate in a slightly acid solution is a slow reaction. But iron(III), silver(I) or manganese(II) has a differential catalytic effect on the oxidation reaction of RB in the presence of 1,10-phenanthroline as the activator. So iron,

  4. Effects of Iron and Manganese Plaques on Arsenic Uptake by Rice Seedlings ( Oryza sativa L.) Grown in Solution Culture Supplied with Arsenateand Arsenite

    Microsoft Academic Search

    W.-J. Liu; Y.-G. Zhu; F. A. Smith

    2005-01-01

    We have shown previously that phosphorus nutrition and iron plaque on the surface of rice roots influence arsenate uptake\\u000a and translocation by rice in hydroponic culture. We have now investigated the role of iron (Fe) and manganese (Mn) plaque\\u000a on arsenate and arsenite uptake and translocation in rice seedlings grown hydroponically. Fe and Mn plaques were clearly visible\\u000a as reddish

  5. Iron et al.: Incorporation of Manganese in the Crystal Lattice of Magnetosome Magnetite

    Microsoft Academic Search

    Tanya Prozorov; Teresa Perez-Gonzalez; Concepcion Jimenez-Lopez; Surya K. Mallapragada; Paul Howse; Dennis A. Bazylinski; Ruslan Prozorov

    2010-01-01

    Incorporation of foreign metal into the crystal matrix of the magnetotactic bacterial magnetite has been attempted worldwide. Recently, presence of small amounts of cobalt and manganese in magnetosome magnetite crystals in cultured and uncultured magnetotactic bacteria, respectively, was reported. Magnetization of the uncultured cells and their magnetosomes were not determined, while only marginal changes in the magnetic properties of the

  6. Toxicogenomics | Article Inhibition of Ape1 Nuclease Activity by Lead, Iron, and Cadmium

    E-print Network

    Daniel R. Mcneill; Avinash Narayana; Heng-kuan Wong; David M. Wilson Iii

    Many environmental metals are co-carcinogens, eliciting their effects via inhibition of DNA repair. Apurinic/apyrimidinic (AP) endonuclease 1 (Ape1) is the major mammalian abasic endonuclease and initiates repair of this cytotoxic/mutagenic lesion by incising the DNA backbone via a Mg 2+-dependent reaction. In this study we examined the effects of arsenite [As(III)], cadmium [Cd(II)], cobalt [Co(II)], iron [Fe(II)], nickel [Ni(II)], and lead [Pb(II)] at concentrations ranging from 0.3 to 100 µM on the incision activity of Ape1 in the presence of 1 mM MgCl 2. Pb(II) and Fe(II) inhibited Ape1 activity at each of the concentrations tested, with an IC 50 (half-maximal inhibitory concentration) of 0.61 and 1.0 µM, respectively. Cd(II) also inhibited Ape1 activity but only at concentrations> 10 µM. No inhibition was seen with As(III), Co(II), or Ni(II). A similar inhibition pattern was observed with the homologous Escherichia coli protein, exonuclease III, but no inhibition was seen with the structurally distinct AP endonuclease

  7. Seasonal changes of body iron status determine cadmium accumulation in the wild bank voles.

    PubMed

    W?ostowski, Tadeusz; Krasowska, Alicja; Sali?ska, Aneta; W?ostowska, Monika

    2009-12-01

    The objective of this study was to examine relations between body iron (Fe) status and cadmium (Cd) accumulation in a small rodent, the bank vole, caught from the wild population in late autumn (November) and early spring (March). The concentrations of Fe in the liver, kidneys, and duodenum in the bank voles from the spring were only 30%, 60%, and 70%, respectively, of those found in the animals from the autumn. An analysis of hematocrit and hemoglobin content of blood showed no significant effect of the season, suggesting that the animals from the spring were not anemic. The exposure to dietary Cd (10 microg/g) for 7 days resulted in 70% higher accumulation of Cd in the liver and kidneys of the spring than autumn bank voles, and the concentration of Cd in the duodenum was 3.5 times higher in the spring animals, despite the fact that relative Cd intake was significantly higher in the autumn bank voles. The data indicate that seasonal changes of body Fe status occurring in the wild bank voles may influence tissue accumulation of Cd. PMID:19352597

  8. Iron deficiency is associated with increased levels of blood cadmium in the Korean general population: Analysis of 2008-2009 Korean National Health and Nutrition Examination Survey data

    SciTech Connect

    Lee, Byung-Kook [Institute of Environmental and Occupational Medicine, Soonchunhyang University, 646 Eupnae-ri, Shinchang-myun, Asan-si, Choongnam 336-745 (Korea, Republic of)] [Institute of Environmental and Occupational Medicine, Soonchunhyang University, 646 Eupnae-ri, Shinchang-myun, Asan-si, Choongnam 336-745 (Korea, Republic of); Kim, Yangho, E-mail: yanghokm@nuri.net [Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, 290-3 Cheonha-Dong, Dong-Gu, Ulsan 682-060 (Korea, Republic of)] [Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, 290-3 Cheonha-Dong, Dong-Gu, Ulsan 682-060 (Korea, Republic of)

    2012-01-15

    Introduction: We present data from the Korean National Health and Nutrition Examination Survey 2008-2009 on the distribution of blood cadmium levels and their association with iron deficiency in a representative sample of the adult Korean population. Methods: Serum ferritin was categorized into three levels: low (serum ferritin <15.0 {mu}g/L), low normal (15.0-30.0 {mu}g/L for women and 15.0-50.0 for men), and normal ({>=}30.0 {mu}g/L for women and {>=}50.0 for men), and its association with blood cadmium level was assessed after adjustment for various demographic and lifestyle factors. Results: Geometric means of blood cadmium in the low serum ferritin group in women, men, and all participants were significantly higher than in the normal group. Additionally, multiple regression analysis after adjusting for various covariates showed that blood cadmium was significantly higher in the low-ferritin group in women, men, and all participants compared with the normal group. We also found an association between serum ferritin and blood cadmium among never-smoking participants. Discussion: We found, similar to other recent population-based studies, an association between iron deficiency and increased blood cadmium in men and women, independent of smoking status. The results of the present study show that iron deficiency is associated with increased levels of blood cadmium in the general population.

  9. Role of the metal in the bonding and properties of bimetallic complexes involving manganese, iron, and cobalt.

    PubMed

    Tereniak, Stephen J; Carlson, Rebecca K; Clouston, Laura J; Young, Victor G; Bill, Eckhard; Maurice, Rémi; Chen, Yu-Sheng; Kim, Hyun Jung; Gagliardi, Laura; Lu, Connie C

    2014-02-01

    A multidentate ligand platform is introduced that enables the isolation of both homo- and heterobimetallic complexes of divalent first-row transition metal ions such as Mn(II), Fe(II), and Co(II). By means of a two-step metalation strategy, five bimetallic coordination complexes were synthesized with the general formula M1M2Cl(py3tren), where py3tren is the triply deprotonated form of N,N,N-tris(2-(2-pyridylamino)ethyl)amine. The metal-metal pairings include dicobalt (1), cobalt-iron (2), cobalt-manganese (3), diiron (4), and iron-manganese (5). The bimetallic complexes have been investigated by X-ray diffraction and X-ray anomalous scattering studies, cyclic voltammetry, magnetometry, Mössbauer spectroscopy, UV-vis-NIR spectroscopy, NMR spectroscopy, combustion analyses, inductively coupled plasma optical emission spectrometry, and ab initio quantum chemical methods. Only the diiron chloride complex in this series contains a metal-metal single bond (2.29 Å). The others show weak metal-metal interactions (2.49 to 2.53 Å). The diiron complex is also distinct with a septet ground state, while the other bimetallic species have much lower spin states from S = 0 to S = 1. We propose that the diiron system has delocalized metal-metal bonding electrons, which seems to correlate with a short metal-metal bond and a higher spin state. Multiconfigurational wave function calculations revealed that, indeed, the metal-metal bonding orbitals in the diiron complex are much more delocalized than those of the dicobalt analogue. PMID:24125042

  10. Chemically bonded phosphate ceramics of trivalent oxides of iron and manganese

    DOEpatents

    Wagh, Arun S. (Orland Park, IL); Jeong, Seung-Young (Westmont, IL)

    2002-01-01

    A new method for combining elemental iron and other metals to form an inexpensive ceramic to stabilize arsenic, alkaline red mud wastes, swarfs, and other iron or metal-based additives, to create products and waste forms which can be poured or dye cast.

  11. Seasonal and locational effects on serum, milk, liver and kidney chromium, manganese, copper, zinc, and iron concentrations of dairy cows.

    PubMed

    Erdogan, Suat; Celik, Sefa; Erdogan, Zeynep

    2004-04-01

    Chromium (Cr), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) concentrations were quantified in serum (n = 112), milk (n = 112), liver (n = 70), and kidney samples (n = 67) of dairy cows from an iron-steel processing region (Payas-Iskenderun) and from an area free of industrial pollution (Antakya) in Hatay, located in Southern Turkey. Samples were collected in the summer and winter and element determinations were carried out by inductively coupled plasma-atomic emission spectrometry. The mean concentrations of selected elements in serum were found to be similar in both regions. Milk samples collected from the nonindustrial region in the summer had higher Cr, Mn, and Zn concentrations than the polluted region. The liver Cu and kidney Mn levels of samples taken from the industrial region in winter were higher than samples of the unpolluted region. Copper and Fe concentrations in milk, Cr, Mn, Zn, and Fe levels in the liver, and Cr, Cu, Zn, and Fe levels in kidney samples were not found to be different among the regions in both seasons. Copper concentrations were below the critical level in the 25% of serum and 32% of liver samples analyzed in this study. Fifteen percent of serum samples and most of the liver samples had lower amounts of Zn than other reported studies. Although slight differences were observed between the industrial and nonindustrial regions, industrial activities and seasonal changes had no significant effect on selected element concentrations on cows and their milk. PMID:15051900

  12. Olfactory bulb uptake and determination of biotransfer factors in the California ground squirrel (Spermophilus beecheyi) exposed to manganese and cadmium in environmental habitats.

    PubMed

    Bench, G; Carlsen, T M; Grant, P G; Wollett, J S; Martinelli, R E; Lewis, J L; Divine, K K

    2001-01-15

    Manganese (Mn) and cadmium (Cd) profiles in olfactory bulbs of California ground squirrels (Spermophilus beecheyi) trapped at Lawrence Livermore National Laboratory's Site 300 facility in California were determined with proton induced X-ray emission (PIXE). As a reference, Mn profiles in olfactory bulbs from laboratory rats exposed via nose-only inhalation to 0.53 mg/m3 Mn in the form of MnCl2 were also determined with PIXE. Atomic absorption spectrophotometry was used to measure soil Mn and Cd contents from the trapping sites and Mn and Cd contents in ground squirrel liver and leg muscle tissues. The data from laboratory rats revealed that Mn uptake into the olfactory bulb occurs via inhalation exposure. Data from ground squirrels and knowledge of the collection sites indicate that although several routes of exposure may occur, fossorial rodent olfactory uptake affords a significant exposure route to Mn and Cd in soils. Measured biotransfer factors (ratio of leg muscle tissue metal content to soil metal content) for Cd in ground squirrels were 10(3)-fold greater than exposure modeling estimates based on oral Cd uptake data from livestock. The measurements for ground squirrel tissues show that when conducting ecological risk assessments for natural habitats considerable care should be taken in selecting transfer factors. Specifically, transfer factors derived from data pertaining to comparable exposure pathways and ecological setting should be used wherever possible. PMID:11347597

  13. Characterization of vanadium, manganese and iron model clusters by vibrational and optical spectroscopic methods

    NASA Astrophysics Data System (ADS)

    Ji, Wenbin

    1999-12-01

    The active ferryl intermediates in the catalytic cycles of heme proteins are subject to interactions from the proximal and distal amino acid residues which control their activities and affect the ?(FeIVO) frequency. The effects of sixth axial ligation, hydrogen bonding, and solvent induced polarization on the resonance Raman (RR) spectra of the ferryl porphyrin analogs, vanadyl (VIVO) porphyrins and their ?-cation radicals, are characterized. ?(VIVO) stretching bands for (VO)TMPyP and (VO)PPIX are observed to be sensitive to the pH value of the aqueous solutions, and reveal a number of coexisting 5-coordinate (c) and 6- c vanadyl porphyrins in solution. Moreover, the ?(VIVO) bands for (VO)TMP and (VO)TPP porphyrins upshift to higher frequencies with the formation of their ?-cation radicals, in agreement with that of the (VO)OEP radical. For both a1u (OEP) and a2u (TPP, TMP) type radicals, an increased positive charge on the porphyrin reduces the porphyrin --> vanadium electron donation, but enhances the oxo --> V donation. The UV-Vis absorption and RR spectroscopic studies on a series of oxo-bridged vanadium(III) and manganese (III, IV) complexes established spectrostructural correlations that are useful as monitors of the structure of vanadium(III) and manganese(III, IV) centers in biological systems. The linear and bent V-O-V dimers display distinctive RR and absorption spectra. The linear V-O-V bridge displays an intense ?-O --> V charge transfer (CT) absorption band and a strongly enhanced symmetric (?s) or antisymmetric (?as) V-O-V stretching band in RR spectra, depending upon terminal ligands. In contrast, the bent bridge shows two ?-O --> V CT bands and both ?s and ?as V- O-V stretches are observed in RR spectra. These ?s and ?as vibrations are used to indicate that the vanadium(III) oxo-bridged dimer intercalates with DNA. The Mn-O-Mn vibrational frequencies in the 400-700 cm -1 region of the oxo-bridged manganese(III, IV) dimers, trimers, and tetramers are characterized and show dependence on the cluster geometry and manganese and oxygen modes of coordination. The Raman frequencies and intensities provide a good estimate of the ground and excited structural states and electronic dynamics mediated by the oxo-bridges.

  14. Effects of iron and manganese in culture solution on their concentrations in roots and shoots of rice plants (Oryza sativa L.) grown under anaerobic conditions

    E-print Network

    Bacha, Richard E

    1976-01-01

    -Fe interactions 42 42 45 45 45 46 52 Root Coating Composition . Chemical composition . Additional analysis . 55 55 59 Table of Contents - (Continued) Page Precipitation and Uptake of Fe and Mn . . . . . . . . . . . . , . . . , 62 Scanning Electron.... Hossner The objectives of this investigation were to determine the relationships between iron and manganese in solution and in the plant, and to study the composition of coatings formed on the root epidermis of rice plants. Rice was transplanted...

  15. Metallation and mismetallation of iron and manganese proteins in vitro and in vivo: the class I ribonucleotide reductases as a case study

    PubMed Central

    Cotruvo, Joseph A.; Stubbe, JoAnne

    2012-01-01

    How cells ensure correct metallation of a given protein and whether a degree of promiscuity in metal binding has evolved are largely unanswered questions. In a classic case, iron- and manganese-dependent superoxide dismutases (SODs) catalyze the disproportionation of superoxide using highly similar protein scaffolds and nearly identical active sites. However, most of these enzymes are active with only one metal, although both metals can bind in vitro and in vivo. Iron(II) and manganese(II) bind weakly to most proteins and possess similar coordination preferences. Their distinct redox properties suggest that they are unlikely to be interchangeable in biological systems except when they function in Lewis acid catalytic roles, yet recent work suggests this is not always the case. This review summarizes the diversity of ways in which iron and manganese are substituted in similar or identical protein frameworks. As models, we discuss (1) enzymes, such as epimerases, thought to use FeII as a Lewis acid under normal growth conditions but which switch to MnII under oxidative stress; (2) extradiol dioxygenases, which have been found to use both FeII and MnII, the redox role of which in catalysis remains to be elucidated; (3) SODs, which use redox chemistry and are generally metal-specific; and (4) the class I ribonucleotide reductases (RNRs), which have evolved unique biosynthetic pathways to control metallation. The primary focus is the class Ib RNRs, which can catalyze formation of a stable radical on a tyrosine residue in their ?2 subunits using either a di-iron or a recently characterized dimanganese cofactor. The physiological roles of enzymes that can switch between iron and manganese cofactors are discussed, as are insights obtained from the studies of many groups regarding iron and manganese homeostasis and the divergent and convergent strategies organisms use for control of protein metallation. We propose that, in many of the systems discussed, “discrimination” between metals is not performed by the protein itself, but it is instead determined by the environment in which the protein is expressed. PMID:22991063

  16. Distribution and genetic diversity of the microorganisms in the biofilter for the simultaneous removal of arsenic, iron and manganese from simulated groundwater.

    PubMed

    Yang, Liu; Li, Xiangkun; Chu, Zhaorui; Ren, Yuhui; Zhang, Jie

    2014-03-01

    A biofilter was developed in this study, which showed an excellent performance with the simultaneous removal of AsIII from 150 to 10mg L(-1) during biological iron and manganese oxidation. The distribution and genetic diversity of the microorganisms along the depth of the biofilter have been investigated using DGGE. Results suggested that Iron oxidizing bacteria (IOB, such as Gallionella, Leptothrix), Manganese oxidizing bacteria (MnOB, such as Leptothrix, Pseudomonas, Hyphomicrobium, Arthrobacter) and AsIII-oxidizing bacteria (AsOB, such as Alcaligenes, Pseudomonas) are dominant in the biofilter. The spatial distribution of IOB, MnOB and AsOB at different depths of the biofilter determined the removal zone of FeII, MnII and AsIII, which site at the depths of 20, 60 and 60cm, respectively, and the corresponding removal efficiencies were 86%, 84% and 87%, respectively. This process shows great potential to the treatment of groundwater contaminated with iron, manganese and arsenic due to its stable performance and significant cost-savings. PMID:24507582

  17. Impact of orchard and tillage management practices on soil leaching of atrazine, potassium, magnesium, manganese, iron, ammonium, nitrates and phosphates

    NASA Astrophysics Data System (ADS)

    Szajdak, L.; Lipiec, J.; Siczek, A.; Kotowska, U.; Nosalewicz, A.

    2009-04-01

    The experiments were carried out on an Orthic Luvisol developed from loess, over limestone, at the experimental field of Lublin Agricultural University in Felin (51o15'N, 22o35'E), Poland. The investigation deals with the problems of leaching's rate of atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,2,3-triazine), potassium, magnesium, manganese, iron, ammonium, nitrates and phosphates from two management systems of soil: (i) conventionally tilled field with main tillage operations including stubble cultivator (10 cm) + harrowing followed by mouldboard ploughing to 20 cm depth, and crop rotation including selected cereals, root crops and papillionaceous crops, (ii) 35-year-old apple orchard field (100x200m) with a permanent sward that was mown in the inter-rows during the growing season. The conventionally tilled plot was under the current management practice for approximately 30 years. Field sites were close to each other (about 150 m). Core samples of 100 cm3 volume and 5 cm diameter were taken from two depths 0-10 cm and 10-20 cm, and were used to determine the soil water characteristic curve. It was observed that management practices impacted on the physic-chemical properties of soils. pH (in H2O) in tilled soil ranged from 5.80 to 5.91. However soil of orchard soil revealed higher values of pH than tilled soil and ranged from 6.36 to 6.40. The content of organic carbon for tilled soil ranged from 1.13 to 1.17%, but in orchard soil from 1.59 to 1.77%. Tillled soil showed broader range of bulk density 1.38-1.62 mg m-3, than orchard soil 1.33-134 mg m-3. The first-order kinetic reaction model was fitted to the experimental atrazine, potassium, magnesium, manganese, iron, nitrates, ammonium and phosphates leaching vs. time data. The concentrations of leached chemical compounds revealed linear curves. The correlation coefficients ranged from -0.873 to -0.993. The first-order reaction constants measured for the orchard soils were from 3.8 to 19 times higher than calculated in tilled soils. Half time of studied substances in tilled soils ranged from 2.55 to 8.71 h, but in orchard soils these parameters were significantly lower and ranged from 0.22 to 0.49 h. It seems that managements practices significantly influences on the rates of leaching for all investigated compounds.

  18. The influence of tin, nickel, and cadmium on the intestinal absorption of iron

    Microsoft Academic Search

    S. G. Schaefer; W. Forth

    1983-01-01

    The influence of increasing doses of cadmium, nickel, and tin on the net absorption of fluid as well as upon the absorption of ⁵⁹Fe, administered as ⁵⁹Fe-(FeSOâ), from tied-off jejunal segments of male Sprague-Dawley rats were investigated. The three metals examined decreased the net absorption of fluid from the jejunal segments progressively with increasing metal doses. Cadmium was the most

  19. Intracellular localization and subsequent redistribution of metal transporters in a rat choroid plexus model following exposure to manganese or iron

    SciTech Connect

    Wang Xueqian [School of Health Sciences, Purdue University, West Lafayette, IN 47907 (United States); Miller, David S. [NIH/NIEHS, Research Triangle Park, NC 27709 (United States); Zheng Wei [School of Health Sciences, Purdue University, West Lafayette, IN 47907 (United States)], E-mail: wz18@purdue.edu

    2008-07-15

    Confocal microscopy was used to investigate the effects of manganese (Mn) and iron (Fe) exposure on the subcellular distribution of metal transporting proteins, i.e., divalent metal transporter 1 (DMT1), metal transporter protein 1 (MTP1), and transferrin receptor (TfR), in the rat intact choroid plexus which comprises the blood-cerebrospinal fluid barrier. In control tissue, DMT1 was concentrated below the apical epithelial membrane, MTP1 was diffuse within the cytosol, and TfR was distributed in vesicles around nuclei. Following Mn or Fe treatment (1 and 10 {mu}M), the distribution of DMT1 was not affected. However, MTP1 and TfR moved markedly toward the apical pole of the cells. These shifts were abolished when microtubules were disrupted. Quantitative RT-PCR and Western blot analyses revealed a significant increase in mRNA and protein levels of TfR but not DMT1 and MTP1 after Mn exposure. These results suggest that early events in the tissue response to Mn or Fe exposure involve microtubule-dependent, intracellular trafficking of MTP1 and TfR. The intracellular trafficking of metal transporters in the choroid plexus following Mn exposure may partially contribute to Mn-induced disruption in Fe homeostasis in the cerebrospinal fluid (CSF) following Mn exposure.

  20. Iron oxide/manganese oxide co-loaded hybrid nanogels as pH-responsive magnetic resonance contrast agents.

    PubMed

    Wang, Xia; Niu, Dechao; Wu, Qing; Bao, Song; Su, Teng; Liu, Xiaohang; Zhang, Shengjian; Wang, Qigang

    2015-06-01

    This work described a proof of concept study of hybrid nanogel-based magnetic resonance contrast agents, SPIO@GCS/acryl/biotin@Mn-gel, abb. as SGM, for highly efficient, pH-responsive T1 and T2 dual-mode magnetic resonance imaging (MRI). SGM have been synthesized by assembling superparamagnetic iron oxide particles into polysaccharide nanoclusters, followed by in-situ reduction of the manganese species on the clusters and a final mild polymerization. The dual-mode SGM showed an interesting pH-responsiveness in in vitro MRI, with both T1 and T2 relaxivities turned "ON" in the acidic environment, along with an increase in the r1 and r2 relaxivity values by 1.7-fold (from 8.9 to 15.3 mM(-1) S(-1)) and 4.9-fold (from 45.7 to 226 mM(-1) S(-1)), due to desirable silencing and de-silencing effects. This interesting acidic-responsiveness was further verified in vivo with both significantly brightened signal of tumor tissue in T1-weighted MR images and a darkened signal in T2-weighted MR images 50 min post-injection of SGM. This smart hybrid nanogel may serve as a promising candidate for further studies of dual-mode (T1 and T2) contrast agents in MRI, due to its high stability, interesting pH-response mechanism and indicative imaging of tumors. PMID:25890733

  1. The neurotoxicity of iron, copper and manganese in Parkinson's and Wilson's diseases.

    PubMed

    Dusek, Petr; Roos, Per M; Litwin, Tomasz; Schneider, Susanne A; Flaten, Trond Peder; Aaseth, Jan

    2014-06-01

    Impaired cellular homeostasis of metals, particularly of Cu, Fe and Mn may trigger neurodegeneration through various mechanisms, notably induction of oxidative stress, promotion of ?-synuclein aggregation and fibril formation, activation of microglial cells leading to inflammation and impaired production of metalloproteins. In this article we review available studies concerning Fe, Cu and Mn in Parkinson's disease and Wilson's disease. In Parkinson's disease local dysregulation of iron metabolism in the substantia nigra (SN) seems to be related to neurodegeneration with an increase in SN iron concentration, accompanied by decreased SN Cu and ceruloplasmin concentrations and increased free Cu concentrations and decreased ferroxidase activity in the cerebrospinal fluid. Available data in Wilson's disease suggest that substantial increases in CNS Cu concentrations persist for a long time during chelating treatment and that local accumulation of Fe in certain brain nuclei may occur during the course of the disease. Consequences for chelating treatment strategies are discussed. PMID:24954801

  2. Manganese, iron and sulfur cycling in a coastal marine sediment, Aarhus bay, Denmark

    Microsoft Academic Search

    Bo Thamdrup; Henrik Fossing; Bo Barker Jørgensen

    1994-01-01

    The seasonal variation in oxidized and reduced pools of Mn, Fe and S, as well as the rates of SO 4 2- reduction, were studied in a fine-grained sediment. Below the 1-5 mm thick oxic zone, a zone of net Mn reduction extended to 1-2 cm depth, while iron reduction was found to 4-6 cm depth. Although the reactive Mn

  3. Effects of dietary cadmium exposure on tissue-specific cadmium accumulation, iron status and expression of iron-handling and stress-inducible genes in rainbow trout: influence of elevated dietary iron.

    PubMed

    Kwong, Raymond W M; Andrés, Jose A; Niyogi, Som

    2011-03-01

    Recent evidences suggest that dietary cadmium (Cd) uptake likely occurs via the dietary iron (Fe) uptake pathway in freshwater fish, at least in part. The present study investigated the interactive effects of dietary Cd and Fe in juvenile rainbow trout (Oncorhynchus mykiss). Fish were treated for four weeks with four different diets: normal Fe, high Fe, normal Fe plus Cd, and high Fe plus Cd. Physiological parameters, tissue-specific Fe and Cd level, plasma Fe status, and tissue-specific mRNA expression of transferrin, metallothioneins (MT-A and MT-B) and heat shock proteins 70 (HSP70a and HSP70b) were analyzed. Exposure to dietary Cd increased Cd burden in the following order: intestine>kidney>stomach>liver>gill>carcass. Interestingly, high dietary Fe reduced Cd accumulation in the stomach and intestine as well as in the wholebody of fish. Dietary Cd increased hepatic transferrin mRNA expression and total Fe binding capacity in the plasma, indicating the effect of Cd on Fe handling in fish. The mRNA expression of MTs and HSP70s was also increased in various tissues following dietary Cd exposure, however the response profile of different MT and HSP70 genes was not consistent among different tissues. In general, MT-A was more responsive to Cd exposure in the intestine and liver, whereas MT-B was more responsive in the kidney. Similarly, HSP70a expression was more sensitive to Cd exposure than HSP70b, particularly in the intestine. Interestingly, high Fe diet suppressed Cd-induced induction of transferrin, MT and HSP70 genes in various tissues. Overall, our study suggests that elevated dietary Fe can reduce Cd accumulation and ameliorate Cd-induced stress responses in freshwater fish. PMID:21371606

  4. Reference values of cadmium, arsenic and manganese in blood and factors associated with exposure levels among adult population of Rio Branco, Acre, Brazil.

    PubMed

    Freire, Carmen; Koifman, Rosalina Jorge; Fujimoto, Denys; de Oliveira Souza, Vanessa Cristina; Barbosa, Fernando; Koifman, Sergio

    2015-06-01

    This study aimed to investigate the distribution and factors influencing blood levels of Cadmium (Cd), Arsenic (As), and Manganese (Mn), and to determine their reference values in a sample of blood donors residing in Rio Branco, capital city of Acre State, Brazil. Blood samples were collected from all blood donors attending the Central Hemotherapic Unit in Rio Branco between 2010 and 2011. Among these, 1183 donors (98.9%) answered to a questionnaire on sociodemographic and lifestyle factors. Blood metal concentrations were determined by atomic spectrometry. Association between Cd, As and Mn levels and donors' characteristics was examined by linear regression analysis. Reference values were estimated as the upper limit of the 95% confidence interval of the 95th percentile of metal levels. References values were 0.87?gL(-1) for Cd, 9.87?gL(-1) for As, and 29.32?gL(-1) for Mn. Reference values of Cd and As in smokers were 2.66 and 10.86?gL(-1), respectively. Factors contributing to increase Cd levels were smoking, ethnicity (non-white), and lower education, whereas drinking tea and non-bottled water were associated with lower Cd. Lower levels of As were associated with higher household income, living near industrial facilities, working in a glass factory, a compost plant or in metal mining activities. Risk factors for Mn exposure were not identified. In general, blood Cd concentrations were in the range of exposure levels reported for other people from the general population, whereas levels of As and Mn were higher than in other non-occupationally exposed populations elsewhere. PMID:25655821

  5. Microbial reduction of manganese and iron: New approaches to carbon cycling. [Shewanella putrefaciens

    SciTech Connect

    Nealson, K.H. (Univ. of Wisconsin, Milwaukee (United States)); Myers, C.R. (Medical Coll. of Wisconsin, Milwaukee (United States))

    1992-02-01

    This brief review introduces the reader to the importance and conceptual aspects of microbial metal reduction by focusing on a single group of Mn(IV)- and Fe(III)-reducing organisms in the group Shewanella putrefaciens. While this group is abundant and of worldwide distribution, it is only the tip of a very large iceberg' of metal reducers. A good example of another metal reducer is the organism GS-15, an obligate anaerobe with substantial carbon versatility and an ability to tolerate very high concentrations of metals. In addition, the authors have now isolated over 200 strains of manganese reducers (MR-203 is their latest organism), consisting of a wide variety of different taxa, including Pseudomonas spp., Bacillus spp., and many others. These isolates are from very diverse environments, including Lake Oneida, N.Y.; Lake Michigan; Green Bay, Wis.; the Black Sea; and Lake Baikal, USSR. A careful coupling of field and laboratory studies will be needed before the importance of these metal-reducing microbes, and their associated activities, are adequately understood.

  6. Relationship of manganese-iron oxides and associated heavy metals to grain size in stream sediments

    USGS Publications Warehouse

    Whitney, P.R.

    1975-01-01

    The distribution of ammonium citrate-leachable lead, zinc and cadmium among size fractions in stream sediments is strongly influenced by the presence of hydrous Mn-Fe oxides in the form of coatings on sediment grains. Distribution curves showing leachable metals as a function of particle size are given for eight samples from streams in New York State. These show certain features in common; in particular two concentrations of metals, one in the finest fractions, and a second peak in the coarse sand and gravel fraction. The latter can be explained as a result of the increasing prevalence and thickness of oxide coatings with increasing particle size, with the oxides serving as collectors for the heavy metals. The distribution of Zn and Cd in most of the samples closely parallels that of Mn; the distribution of Pb is less regular and appears to be related to Fe in some samples and Mn in others. The concentration of metals in the coarse fractions due to oxide coatings, combined with the common occurrence of oxide deposition in streams of glaciated regions, raises the possibility of using coarse materials for geochemical surveys and environmental heavy-metal studies. ?? 1975.

  7. Iron as a possible aggravating factor for osteopathy in itai-itai disease, a disease associated with chronic cadmium intoxication

    SciTech Connect

    Noda, M.; Yasuda, M.; Kitagawa, M. (Toyama Medical and Pharmaceutical Univ. (Japan))

    1991-03-01

    Itai-itai disease is thought to be the result of chronic cadmium (Cd) intoxication. We examined 23 autopsy cases of itai-itai disease and 18 cases of sudden death as controls. Urine and blood samples from 10 patients were collected before they died and revealed the presence of severe anemia and renal tubular injuries. Undecalcified sections of iliac bone were stained with Aluminon reagent, and ammonium salt of aurintricarboxylic acid, and Prussian blue reagent in all cases of itai-itai disease. These two reagents reacted at the same mineralization fronts. X-ray microanalysis revealed the presence of iron at mineralization fronts in itai-itai disease. Five patients showed evidence of hemosiderosis in the liver, spleen, and pancreas, probably as a result of post transfusion iron overload. Renal calculi and calcified aortic walls were also stained with Prussian blue reagent in several patients. Neither ferritin nor transferrin were visualized at mineralization fronts in itai-itai disease by immunohistochemical staining. These results suggest that iron is bound to calcium or to calcium phosphate by a physicochemical reaction. A marked osteomalacia was observed in 10 cases of itai-itai disease by histomorphometry. Regression analyses of data from cases of itai-itai disease suggested that an Aluminon-positive metal inhibited mineralization and that renal tubules were injured. Since bone Cd levels were increased in itai-itai disease, it is likely that renal tubules were injured by exposure to Cd. Therefore, stainable bone iron is another possible aggravating factor for osteopathy in itai-itai disease, and a synergistic effect between iron and Cd on mineralization is proposed.

  8. MANGANESE--1997 49.1 By Thomas S. Jones

    E-print Network

    Torgersen, Christian

    MANGANESE--1997 49.1 MANGANESE By Thomas S. Jones Manganese (Mn) is essential to iron and steel,includingitsironmakingcomponent,hasaccounted for most domestic manganese demand, presently in the range of 85% to 90% of the total demand. Among a variety of other uses, manganese is a key component of certain widely used aluminum alloys and is used

  9. IRON NUTRITION INFLUENCE ON CADMIUM ACCUMULATION BY ARABIDOPSIS THALIANA (L.) HEYNH

    EPA Science Inventory

    Greenhouse experiments were conducted to determine whether Arabidopsis thaliana (L.) Heynh, a putative Fe-efficient species, accumulated higher concentrations of Cd from a sparingly soluble Cd source (cadmium dihydrogen phosphate) when growing in Fe-deficient rather than in Fe-su...

  10. The Abundance of Iron-Peak Elements and the Dust Composition in eta Carinae: Manganese

    NASA Technical Reports Server (NTRS)

    Bautista, M. A.; Melendez, M.; Hartman, H.; Gull, T. R.; Lodders, K.

    2010-01-01

    We study the chemical abundances of the Strontium Filament found in the ejecta of (eta) Carinae. In particular, we derive the abundances of iron-peak elements front spectra of their singly ionized ions present in the optical/IR spectra. In this paper we analyze the spectrum of Mn II using a new non-LTE model for this system. In constructing this models we carried out theoretical calculations of radiative transition rates and electron impact excitation rate coefficients. We find that relative to Ni the gas phase abundance ratio of Mn is roughly solar, similar to the Cr abundance but in contrast to the large enhancements in the abundances of Sc and Ti. NVe interpret this result as an indication of non-equilibrium condensation in the ejecta of (eta) Carinae.

  11. Arsenic, iron, lead, manganese, and uranium concentrations in private bedrock wells in southeastern New Hampshire, 2012-2013

    USGS Publications Warehouse

    Flanagan, Sarah M.; Belaval, Marcel; Ayotte, Joseph D.

    2014-01-01

    Trace metals, such as arsenic, iron, lead, manganese, and uranium, in groundwater used for drinking have long been a concern because of the potential adverse effects on human health and the aesthetic or nuisance problems that some present. Moderate to high concentrations of the trace metal arsenic have been identified in drinking water from groundwater sources in southeastern New Hampshire, a rapidly growing region of the State (Montgomery and others, 2003). During the past decade (2000–10), southeastern New Hampshire, which is composed of Hillsborough, Rockingham, and Strafford Counties, has grown in population by nearly 48,700 (or 6.4 percent) to 819,100. These three counties contain 62 percent of the State’s population but encompass only about 22 percent of the land area (New Hampshire Office of Energy and Planning, 2011). According to a 2005 water-use study (Hayes and Horn, 2009), about 39 percent of the population in these three counties in southeastern New Hampshire uses private wells as sources of drinking water, and these wells are not required by the State to be routinely tested for trace metals or other contaminants. Some trace metals have associated human-health benchmarks or nonhealth guidelines that have been established by the U.S. Environmental Protection Agency (EPA) to regulate public water supplies. The EPA has established a maximum contaminant level (MCL) of 10 micrograms per liter (?g/L) for arsenic (As) and a MCL of 30 ?g/L for uranium (U) because of associated health risks (U.S. Environmental Protection Agency, 2012). Iron (Fe) and manganese (Mn) are essential for human health, but Mn at high doses may have adverse cognitive effects in children (Bouchard and others, 2011; Agency for Toxic Substances and Disease Registry, 2012); therefore, the EPA has issued a lifetime health advisory (LHA) of 300 ?g/L for Mn. Recommended secondary maximum contaminant levels (SMCLs) for Fe (300 ?g/L) and Mn (50 ?g/L) were established primarily as nonhealth guidelines—based on aesthetic considerations, such as taste or the staining of laundry and plumbing fixtures—because these contaminants, at the SMCLs, are not considered to present risks to human health. Because lead (Pb) contamination of drinking water typically results from corrosion of plumbing materials belonging to water-system customers but still poses a risk to human health, the EPA established an action level (AL) of 15 ?g/L for Pb instead of an MCL or SMCL (U.S. Environmental Protection Agency, 2012). The 15-?g/L AL for Pb has been adopted by the New Hampshire Department of Environmental Services for public water systems, and if exceeded, the public water system must inform their customers and undertake additional actions to control corrosion in the pipes of the distribution system (New Hampshire Department of Environmental Services, 2013). Unlike the quality of drinking water provided by public water suppliers, the quality of drinking water obtained from private wells in New Hampshire is not regulated; consequently, private wells are sampled only when individual well owners voluntarily choose to sample them. The U.S. Geological Survey (USGS), in cooperation with the EPA New England, conducted an assessment in 2012–13 to provide private well owners and State and Federal health officials with information on the distribution of trace-metal (As, Fe, Pb, Mn, and U) concentrations in groundwater from bedrock aquifers in the three counties of southeastern New Hampshire. This fact sheet analyzes data from water samples collected by a randomly selected group of private well owners from the three-county study area and describes the major findings for trace-metal concentrations.

  12. Biodistribution and acute toxicity of a nanofluid containing manganese iron oxide nanoparticles produced by a mechanochemical process.

    PubMed

    Bellusci, Mariangela; La Barbera, Aurelio; Padella, Franco; Mancuso, Mariateresa; Pasquo, Alessandra; Grollino, Maria Giuseppa; Leter, Giorgio; Nardi, Elisa; Cremisini, Carlo; Giardullo, Paola; Pacchierotti, Francesca

    2014-01-01

    Superparamagnetic iron oxide nanoparticles are candidate contrast agents for magnetic resonance imaging and targeted drug delivery. Biodistribution and toxicity assessment are critical for the development of nanoparticle-based drugs, because of nanoparticle-enhanced biological reactivity. Here, we investigated the uptake, in vivo biodistribution, and in vitro and in vivo potential toxicity of manganese ferrite (MnFe2O4) nanoparticles, synthesized by an original high-yield, low-cost mechanochemical process. Cultures of murine Balb/3T3 fibroblasts were exposed for 24, 48, or 72 hours to increasing ferrofluid concentrations. Nanoparticle cellular uptake was assessed by flow-cytometry scatter-light measurements and microscopy imaging after Prussian blue staining; cytotoxicity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and colony-forming assays. After a single intravenous injection, in vivo nanoparticle biodistribution and clearance were evaluated in mice by Mn spectrophotometric determination and Prussian blue staining in the liver, kidneys, spleen, and brain at different posttreatment times up to 21 days. The same organs were analyzed for any possible histopathological change. The in vitro study demonstrated dose-dependent nanoparticle uptake and statistically significant cytotoxic effects from a concentration of 50 ?g/mL for the MTT assay and 20 ?g/mL for the colony-forming assay. Significant increases in Mn concentrations were detected in all analyzed organs, peaking at 6 hours after injection and then gradually declining. Clearance appeared complete at 7 days in the kidneys, spleen, and brain, whereas in the liver Mn levels remained statistically higher than in vehicle-treated mice up to 3 weeks postinjection. No evidence of irreversible histopathological damage to any of the tested organs was observed. A comparison of the lowest in vitro toxic concentration with the intravenously injected dose and the administered dose of other ferrofluid drugs currently in clinical practice suggests that there might be sufficient safety margins for further development of our formulation. PMID:24790434

  13. Biodistribution and acute toxicity of a nanofluid containing manganese iron oxide nanoparticles produced by a mechanochemical process

    PubMed Central

    Bellusci, Mariangela; La Barbera, Aurelio; Padella, Franco; Mancuso, Mariateresa; Pasquo, Alessandra; Grollino, Maria Giuseppa; Leter, Giorgio; Nardi, Elisa; Cremisini, Carlo; Giardullo, Paola; Pacchierotti, Francesca

    2014-01-01

    Superparamagnetic iron oxide nanoparticles are candidate contrast agents for magnetic resonance imaging and targeted drug delivery. Biodistribution and toxicity assessment are critical for the development of nanoparticle-based drugs, because of nanoparticle-enhanced biological reactivity. Here, we investigated the uptake, in vivo biodistribution, and in vitro and in vivo potential toxicity of manganese ferrite (MnFe2O4) nanoparticles, synthesized by an original high-yield, low-cost mechanochemical process. Cultures of murine Balb/3T3 fibroblasts were exposed for 24, 48, or 72 hours to increasing ferrofluid concentrations. Nanoparticle cellular uptake was assessed by flow-cytometry scatter-light measurements and microscopy imaging after Prussian blue staining; cytotoxicity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and colony-forming assays. After a single intravenous injection, in vivo nanoparticle biodistribution and clearance were evaluated in mice by Mn spectrophotometric determination and Prussian blue staining in the liver, kidneys, spleen, and brain at different posttreatment times up to 21 days. The same organs were analyzed for any possible histopathological change. The in vitro study demonstrated dose-dependent nanoparticle uptake and statistically significant cytotoxic effects from a concentration of 50 ?g/mL for the MTT assay and 20 ?g/mL for the colony-forming assay. Significant increases in Mn concentrations were detected in all analyzed organs, peaking at 6 hours after injection and then gradually declining. Clearance appeared complete at 7 days in the kidneys, spleen, and brain, whereas in the liver Mn levels remained statistically higher than in vehicle-treated mice up to 3 weeks postinjection. No evidence of irreversible histopathological damage to any of the tested organs was observed. A comparison of the lowest in vitro toxic concentration with the intravenously injected dose and the administered dose of other ferrofluid drugs currently in clinical practice suggests that there might be sufficient safety margins for further development of our formulation. PMID:24790434

  14. Foliar-applied glyphosate substantially reduced uptake and transport of iron and manganese in sunflower (Helianthus annuus L.) plants.

    PubMed

    Eker, Selim; Ozturk, Levent; Yazici, Atilla; Erenoglu, Bulent; Romheld, Volker; Cakmak, Ismail

    2006-12-27

    Evidence clearly shows that cationic micronutrients in spray solutions reduce the herbicidal effectiveness of glyphosate for weed control due to the formation of metal-glyphosate complexes. The formation of these glyphosate-metal complexes in plant tissue may also impair micronutrient nutrition of nontarget plants when exposed to glyphosate drift or glyphosate residues in soil. In the present study, the effects of simulated glyphosate drift on plant growth and uptake, translocation, and accumulation (tissue concentration) of iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) were investigated in sunflower (Helianthus annuus L.) plants grown in nutrient solution under controlled environmental conditions. Glyphosate was sprayed on plant shoots at different rates between 1.25 and 6.0% of the recommended dosage (i.e., 0.39 and 1.89 mM glyphosate isopropylamine salt). Glyphosate applications significantly decreased root and shoot dry matter production and chlorophyll concentrations of young leaves and shoot tips. The basal parts of the youngest leaves and shoot tips were severely chlorotic. These effects became apparent within 48 h after the glyphosate spray. Glyphosate also caused substantial decreases in leaf concentration of Fe and Mn while the concentration of Zn and Cu was less affected. In short-term uptake experiments with radiolabeled Fe (59Fe), Mn (54Mn), and Zn (65Zn), root uptake of 59Fe and 54Mn was significantly reduced in 12 and 24 h after application of 6% of the recommended dosage of glyphosate, respectively. Glyphosate resulted in almost complete inhibition of root-to-shoot translocation of 59Fe within 12 h and 54Mn within 24 h after application. These results suggest that glyphosate residues or drift may result in severe impairments in Fe and Mn nutrition of nontarget plants, possibly due to the formation of poorly soluble glyphosate-metal complexes in plant tissues and/or rhizosphere interactions. PMID:17177536

  15. Low-temperature superacid catalysis: Reactions of n - butane and propane catalyzed by iron- and manganese-promoted sulfated zirconia

    SciTech Connect

    Tsz-Keung, Cheung; d`Itri, J.L.; Lange, F.C.; Gates, B.C. [Univ. of California, Davis, CA (United States)

    1995-12-31

    The primary goal of this project is to evaluate the potential value of solid superacid catalysts of the sulfated zirconia type for light hydrocarbon conversion. The key experiments catalytic testing of the performance of such catalysts in a flow reactor fed with streams containing, for example, n-butane or propane. Fe- and Mn-promoted sulfated zirconia was used to catalyze the conversion of n-butane at atmospheric pressure, 225-450{degrees}C, and n-butane partial pressures in the range of 0.0025-0.01 atm. At temperatures <225{degrees}C, these reactions were accompanied by cracking; at temperatures >350{degrees}C, cracking and isomerization occurred. Catalyst deactivation, resulting at least in part from coke formation, was rapid. The primary cracking products were methane, ethane, ethylene, and propylene. The observation of these products along with an ethane/ethylene molar ratio of nearly 1 at 450{degrees}C is consistent with cracking occurring, at least in part, by the Haag-Dessau mechanism, whereby the strongly acidic catalyst protonates n-butane to give carbonium ions. The rate of methane formation from n-butane cracking catalyzed by Fe- and Mn-promoted sulfated zirconia at 450{degrees}C was about 3 x 10{sup -8} mol/(g of catalyst {center_dot}s). The observation of butanes, pentanes, and methane as products is consistent with Olah superacid chemistry, whereby propane is first protonated by a very strong acid to form a carbonium ion. The carbonium ion then decomposes into methane and an ethyl cation which undergoes oligocondensation reactions with propane to form higher molecular weight alkanes. The results are consistent with the identification of iron- and manganese-promoted sulfated zirconia as a superacid.

  16. Zinc, Iron, Manganese and Copper Uptake Requirement in Response to Nitrogen Supply and the Increased Grain Yield of Summer Maize

    PubMed Central

    Xue, Yanfang; Yue, Shanchao; Zhang, Wei; Liu, Dunyi; Cui, Zhenling; Chen, Xinping; Ye, Youliang; Zou, Chunqin

    2014-01-01

    The relationships between grain yields and whole-plant accumulation of micronutrients such as zinc (Zn), iron (Fe), manganese (Mn) and copper (Cu) in maize (Zea mays L.) were investigated by studying their reciprocal internal efficiencies (RIEs, g of micronutrient requirement in plant dry matter per Mg of grain). Field experiments were conducted from 2008 to 2011 in North China to evaluate RIEs and shoot micronutrient accumulation dynamics during different growth stages under different yield and nitrogen (N) levels. Fe, Mn and Cu RIEs (average 64.4, 18.1and 5.3 g, respectively) were less affected by the yield and N levels. ZnRIE increased by 15% with an increased N supply but decreased from 36.3 to 18.0 g with increasing yield. The effect of cultivars on ZnRIE was similar to that of yield ranges. The substantial decrease in ZnRIE may be attributed to an increased Zn harvest index (from 41% to 60%) and decreased Zn concentrations in straw (a 56% decrease) and grain (decreased from 16.9 to 12.2 mg kg?1) rather than greater shoot Zn accumulation. Shoot Fe, Mn and Cu accumulation at maturity tended to increase but the proportions of pre-silking shoot Fe, Cu and Zn accumulation consistently decreased (from 95% to 59%, 90% to 71% and 91% to 66%, respectively). The decrease indicated the high reproductive-stage demands for Fe, Zn and Cu with the increasing yields. Optimized N supply achieved the highest yield and tended to increase grain concentrations of micronutrients compared to no or lower N supply. Excessive N supply did not result in any increases in yield or micronutrient nutrition for shoot or grain. These results indicate that optimized N management may be an economical method of improving micronutrient concentrations in maize grain with higher grain yield. PMID:24705926

  17. Bioaccumulation of iron, zinc, cadmium and chromium by juvenile snail Limicolaria aurora J., fed edible mushroom Pleurotus spp from Niger Delta, Nigeria.

    PubMed

    Ebenso, I E; Solomon, I P; Akoje, C C; Akpan, I P; Eko, P M; Akpan, E A; Omole, A J

    2013-03-01

    The effects of uptake of metals (iron, zinc, cadmium and chromium) by juvenile snail Limicolaria aurora fed edible mushroom Pleurotus spp from 3 contaminated farm sites and a laboratory grown species (control) respectively were investigated. The 120 snails were fed in plastic snaileries for 4 weeks in the laboratory. Control site was risk free. Metal uptake was low and bioaccumulation in L. aurora tissue was below FAO/WHO standard of 1 mg/kg for chromium and cadmium. Snails were considered safe for consumption. PMID:23229305

  18. Redox zonation at the saline-influenced boundaries of a permeable surficial aquifer: effects of physical forcing on the biogeochemical cycling of iron and manganese

    NASA Astrophysics Data System (ADS)

    Snyder, M.; Taillefert, M.; Ruppel, C.

    2004-08-01

    Research investigating geochemical changes accompanying subsurface mixing of fresh and saline water has primarily focused on cation exchange and mineral dissolution/precipitation reactions. In this study, we report on redox species zonation at the boundaries of a freshwater lens confined beneath a small, permeable island surrounded by saline marshes and tidal creeks and located on the estuary side of Sapelo Island, Georgia. The spatial and temporal distribution of the chemical species in the aquifer implies that the freshwater lens resists saline intrusion by maintaining constant advection across the salinity gradient. As a result, the biogeochemical processes in this aquifer seem to have reached a quasi steady-state very close to equilibrium. Redox reactions associated with natural organic matter oxidation may also play an important role at the salinity transition. Surprisingly, aerobic respiration and microbial iron reduction seem to be the main pathways for natural organic matter oxidation. Sulfate reduction is not significant despite the high concentration of sulfate available, and manganese oxides are probably chemically reduced by dissolved sulfide and Fe 2+. This study is the first to demonstrate that iron and manganese reduction takes place at the salinity transitions bounding both sides of an island freshwater lens and that microbial iron reduction accounts for most of anaerobic respiration of natural organic matter at these transitions.

  19. Iron and Manganese Pyrophosphates as Cathodes for Lithium-Ion Batteries

    SciTech Connect

    Zhou, Hui; Upreti, Shailesh; Chernova, Natasha A.; Hautier, Geoffroy; Ceder, Gerbrand; Whittingham, M. Stanley (MIT); (SUNY-Binghamton)

    2011-11-07

    The mixed-metal phases, (Li{sub 2}Mn{sub 1-y}Fe{sub y}P{sub 2}O{sub 7}, 0 {le} y {le} 1), were synthesized using a 'wet method', and found to form a solid solution in the P2{sub 1}/a space group. Both thermogravimetric analysis and magnetic susceptibility measurements confirm the 2+ oxidation state for both the Mn and Fe. The electrochemical capacity improves as the Fe concentration increases, as do the intensities of the redox peaks of the cyclic voltammogram, indicating higher lithium-ion diffusivity in the iron phase. The two Li{sup +} ions in the three-dimensional tunnel structure of the pyrophosphate phase allows for the cycling of more than one lithium per redox center. Cyclic voltammograms show a second oxidation peak at 5 V and 5.3 V, indicative of the extraction of the second lithium ion, in agreement with ab initio computation predictions. Thus, electrochemical capacities exceeding 200 Ah/kg may be achieved if a stable electrolyte is found.

  20. Evolution of novel bioresorbable iron-manganese implant surfaces and their degradation behaviors in vitro.

    PubMed

    Heiden, Michael; Walker, Emily; Nauman, Eric; Stanciu, Lia

    2015-01-01

    The purpose of this study is to advance understanding of surface degradation kinetics for Fe-Mn bioresorbable alloys (specifically Fe-20%Mn) and target degradable fracture fixation implants for hard tissues. This study addresses how arc melted Fe-20%Mn discs degrade in a static, osteogenic medium for up to a 3 month time span. Degradation behavior of these bulk alloys was investigated using both mass loss tests for measuring long-term corrosion rates and potentiostatic tests for following the instantaneous rate of degradation. It was discovered that cold-rolling Fe-20%Mn to 77% cold work (CW) suppressed the instantaneous corrosion rate compared with the cast structure. It was also found that an unstable iron-rich oxide layer forms on the entire surface of these bulk samples and the act of machining the bulk metal into a defined shape may affect the morphology of the oxide layer on the outer edge of the samples during degradation. The mechanisms behind the surface evolution of these potential orthopedic implants are investigated in detail. PMID:24616416

  1. Development and application of 16S rRNA-targeted probes for detection of iron- and manganese-oxidizing sheathed bacteria in environmental samples.

    PubMed Central

    Siering, P L; Ghiorse, W C

    1997-01-01

    Comparative sequence analysis of the 16S rRNA genes from several Leptothrix and Sphaerotilus strains led to the design of an oligonucleotide probe (PS-1) based on a sequence within the hypervariable region 1 specific for four Leptothrix strains and for one of the four Sphaerotilus natans strains examined. Another probe (PSP-6) was based on a sequence within the hypervariable region 2. PSP-6 was specific for one of the two evolutionary lineages previously described for Leptothrix spp. (P. L. Siering and W. C. Ghiorse, Int. J. Syst. Bacteriol. 46:173-182, 1996). Fluorescein-labeled oligonucleotide probes were synthesized, and their specificity for fluorescence in situ hybridization identification was confirmed by a laser scanning microscopy technique (W. C. Ghiorse, D. N. Miller, R. L. Sandoli, and P. L. Siering, Microsc. Res. Tech. 33:73-86, 1996) to compare whole-cell hybridizations of closely related bacteria. Probe specificity was also tested in dot blot against total RNA isolated from four Leptothrix strains, four Sphaerotilus strains, and 15 other members of the class Proteobacteria. When the probes were tested on samples from the Sapsucker Woods wetland habitat where Leptothrix spp. are thought to play a role in manganese and iron oxidation, positive signals were obtained from several sheathed filamentous bacteria including some that were morphologically similar to previously isolated strains of "Leptothrix discophora." Other unknown filamentous sheathed bacteria also gave strong positive signals. This work provides a foundation for future studies correlating the presence of members of the Leptothrix-Sphaerotilus group of sheathed bacteria with manganese and iron oxidation activity in habitats where biological iron and manganese oxidation are important environmental processes. PMID:9023942

  2. Development and application of 16S rRNA-targeted probes for detection of iron- and manganese-oxidizing sheathed bacteria in environmental samples.

    PubMed

    Siering, P L; Ghiorse, W C

    1997-02-01

    Comparative sequence analysis of the 16S rRNA genes from several Leptothrix and Sphaerotilus strains led to the design of an oligonucleotide probe (PS-1) based on a sequence within the hypervariable region 1 specific for four Leptothrix strains and for one of the four Sphaerotilus natans strains examined. Another probe (PSP-6) was based on a sequence within the hypervariable region 2. PSP-6 was specific for one of the two evolutionary lineages previously described for Leptothrix spp. (P. L. Siering and W. C. Ghiorse, Int. J. Syst. Bacteriol. 46:173-182, 1996). Fluorescein-labeled oligonucleotide probes were synthesized, and their specificity for fluorescence in situ hybridization identification was confirmed by a laser scanning microscopy technique (W. C. Ghiorse, D. N. Miller, R. L. Sandoli, and P. L. Siering, Microsc. Res. Tech. 33:73-86, 1996) to compare whole-cell hybridizations of closely related bacteria. Probe specificity was also tested in dot blot against total RNA isolated from four Leptothrix strains, four Sphaerotilus strains, and 15 other members of the class Proteobacteria. When the probes were tested on samples from the Sapsucker Woods wetland habitat where Leptothrix spp. are thought to play a role in manganese and iron oxidation, positive signals were obtained from several sheathed filamentous bacteria including some that were morphologically similar to previously isolated strains of "Leptothrix discophora." Other unknown filamentous sheathed bacteria also gave strong positive signals. This work provides a foundation for future studies correlating the presence of members of the Leptothrix-Sphaerotilus group of sheathed bacteria with manganese and iron oxidation activity in habitats where biological iron and manganese oxidation are important environmental processes. PMID:9023942

  3. Solid state 31phosphorus nuclear magnetic resonance of iron-, manganese-, and copper-containing synthetic hydroxyapatites

    NASA Technical Reports Server (NTRS)

    Sutter, B.; Taylor, R. E.; Hossner, L. R.; Ming, D. W.

    2002-01-01

    The incorporation of micronutrients into synthetic hydroxyapatite (SHA) is proposed for slow release of these nutrients to crops in the National Aeronautics and Space Administration's (NASA's) Advanced Life Support (ALS) program for Lunar or Martian outposts. Solid state 31P nuclear magnetic resonance (NMR) was utilized to examine the paramagnetic effects of Fe3+, Mn2+, and Cu2+ to determine if they were incorporated into the SHA structure. Separate Fe3+, Mn2+, and Cu2+ containing SHA materials along with a transition metal free SHA (pure-SHA) were synthesized using a precipitation method. The proximity (<1 nm) of the transition metals to the 31P nuclei of SHA were apparent when comparing the integrated 31P signal intensities of the pure-SHA (87 arbitrary units g-1) with the Fe-, Mn-, and Cu-SHA materials (37-71 arbitrary units g-1). The lower integrated 31P signal intensities of the Fe-, Mn-, and Cu-SHA materials relative to the pure-SHA suggested that Fe3+, Mn2+, and Cu2+ were incorporated in the SHA structure. Further support for Fe3+, Mn2+, and Cu2+ incorporation was demonstrated by the reduced spin-lattice relaxation constants of the Fe-, Mn-, and Cu-SHA materials (T'=0.075-0.434s) relative to pure-SHA (T1=58.4s). Inversion recovery spectra indicated that Fe3+, Mn2+, and Cu2+ were not homogeneously distributed about the 31P nuclei in the SHA structure. Extraction with diethylene-triamine-penta-acetic acid (DTPA) suggested that between 50 and 80% of the total starting metal concentrations were incorporated in the SHA structure. Iron-, Mn-, and Cu-containing SHA are potential slow release sources of Fe, Mn, and Cu in the ALS cropping system.

  4. The Effects of Cadmium and Iron on Catalase Activities in Tubifex

    Microsoft Academic Search

    Tao Chen; Arthur Furst; Paul K. Chien

    1994-01-01

    The effects of 1 ?\\/M Cd(II), alone and in combination with several concentrations of Fe(II), were investigated in Tubifex tubifex (a fresh water worm) by the determination of catalase activities in vivo at 6, 12, 24, and 48 h. At 6 h postexposure the catalase activities in all cadmium-exposed groups dropped below control values. At 12 and 24 h the

  5. The precipitation of aluminum, iron and manganese at the junction of Deer Creek with the Snake River in Summit County, Colorado

    USGS Publications Warehouse

    Theobald, P.K., Jr.; Lakin, H.W.; Hawkins, D.B.

    1963-01-01

    The oxidation of disseminated pyrite in relatively acid schists and gneisses of the Snake River drainage basin provides abundant iron sulfate and sulfuric acid to ground and surface water. This acid water dissolves large quantities of many elements, particularly aluminum and surprisingly large quantities of elements, such as magnesium and zinc, not expected to be abundant in the drainage basin. The adjoining drainage to the west, Deer Creek, is underlain by basic rocks, from which the water inherits a high pH. Despite the presence of base- and precious- metal veins in the drainage basin of Deer Creek, it carries less metal than the Snake River. The principal precipitate on the bed of the Snake River is hydrated iron oxide with small quantities of the other metals. In Deer Creek manganese oxide is precipitated with iron oxide and large quantities of other metals are carried down with this precipitate. Below the junction of these streams the pH stabilizes at a near-neutral value. Iron is removed from the Snake River water at the junction, and aluminum is precipitated for some distance downstream. The aluminum precipitate carries down other metals in concentrations slightly less than that in the manganese precipitate on Deer Creek. The natural processes observed in this junction if carried to a larger scale could provide the mechanism described by Ansheles (1927) for the formation of bauxite. In the environment described, geochemical exploration by either water or stream sediment techniques is difficult because of (1) the extreme pH differential between the streams above their junction and (2) the difference in the precipitates formed on the streambeds. ?? 1963.

  6. Effect of manganese and iron at a neutral and acidic pH on the hematology of the banded Tilapia (Tilapia sparrmanii)

    SciTech Connect

    Wepener, V.; Van Vuren, J.H.J.; Du Preez, H.H. [Rand Afrikaans Univ., Johannesburg (South Africa)

    1992-10-01

    The pollution of natural water bodies is a common phenomenon in developing countries. Increases in population densities lead to increased mining and industrial activities in the area. With the establishment of gold and coal mines in South Africa, several industrial zones were created to support the mining industry. Many of these industries consist of heavy metal processing factories. Over the years pollution from the mines has led to acidification of the streams and lakes in the Transvaal. It was also found that high concentrations of heavy metals occurred in the water, sediments, plants and fish tissue in the affected water systems. Of all the heavy metals, iron and manganese were found in the highest concentrations. In order to determine the subtle, non-lethal effects induced by sublethal concentrations of heavy metals on the physiology of fish, it is necessary to monitor certain clinical parameters. The use of hematological methods as indicators of sublethal stress can supply valuable information concerning the physiological reactions of fish in a changing environment. The reason for this is the close association between the circulatory system of the fish and the external environment. The objective of the present paper was to evaluate the effects of manganese and iron at a neutral and acidic pH on the hematology of Tilapia sparrmanii. 19 refs., 2 figs.

  7. Long-term removal and retention of iron and manganese from acidic mine drainage by wetlands. Volume 1. Methods, results, and appendices. Final report, July 1987-January 1990

    SciTech Connect

    Brooks, R.P.; Unz, R.F.; Davis, L.K.; Tarutis, W.J.; Yanchunas, J.

    1990-01-01

    A promising low-technology solution for treating acidic mine drainage (AMD) emanating from coal mined lands involves the use of constructed wetlands. The research was directed at addressing questions about retention mechanisms for the long-term storage of iron and manganese in constructed wetlands dominated by broad-leaved cattails (Typha latifolia). Three sites in central Pennsylvania spanning the range of water chemistry parameters found in AMD were investigated. When the AMD was circumneutral, and metal loadings were low, 79% of the iron, and 48% of the manganese were retained on average. In the highly acidic site (pH approx. = 3), < 10% of the metal loadings were retained. The primary retention mechanism appears to be the formation of metal oxides in the aerobic zones of the sediments. Although most microbial isolates extracted from sediment cores originated in the aerobic portions of the sediments, there was no evidence that they were transforming metals. When AMD is circumneutral and metal loadings are low, constructed wetlands can be an effective approach to treating mine drainage. At sites with highly acidic waters and high metal loadings, the use of constructed wetlands to treat AMD may be ineffectual, and should be implemented with caution.

  8. Effect of ultrasonic agitation on the release of copper, iron, manganese and zinc from soil and sediment using the BCR three-stage sequential extraction.

    PubMed

    Davidson, C M; Delevoye, G

    2001-08-01

    An ultrasonic bath and an ultrasonic probe have been used to develop rapid versions of the three-stage Community Bureau of Reference (BCR, now the Standards, Measurement and Testing Programme) sequential extraction procedure. The effect of the ultrasonic treatments on the extraction of copper, iron, manganese and zinc from a sewage sludge-amended soil has been assessed. Recoveries similar to those of conventional shaking (i.e., conventional value, +/- 30%) could generally be obtained for copper, manganese and zinc, but not for the important matrix element iron. With the use of compromise sonication conditions, steps 1, 2 and 3 of the sequential extraction (excluding the hydrogen peroxide digestion in step 3, which was not performed with sonication) could be completed in 3, 5 and 1 min, respectively, using the ultrasonic probe, and in 3, 1 and 1 h, respectively, using the bath. The extraction procedures developed using the soil performed well when applied to lake sediment BCR CRM 601. Analyte partitioning was generally similar to that obtained with mechanical shaking, and overall metal recoveries were 84-98% of those obtained with the conventional BCR protocol, except for copper extracted with the probe (74%). Poorer performance (analyte recoveries, 58-104%) was obtained when the methods were applied to an intertidal sediment. This highlights the difficulty of developing a version of the BCR extraction, with ultrasonic assistance, which gives a performance equivalent to conventional shaking when applied to different substrates. PMID:11523440

  9. Organic Constituents and Complexation of Nickel(II), Iron(III), Cadmium(II), and plutonium(IV) in Soybean Xylem Exudates 1

    PubMed Central

    Cataldo, Dominic A.; McFadden, Kristin M.; Garland, Thomas R.; Wildung, Raymond E.

    1988-01-01

    The xylem exudates of soybean (Glycine max cv Williams), provided with fixed N, were characterized as to their organic constituents and in vivo and in vitro complexation of plutonium, iron, cadmium, and nickel. Ion exchange fractionation of whole exudates into their compound classes (organic acid, neutral, amino acid, and polyphosphate), followed by thinlayer electrophoresis, permitted evaluation of the types of ligands which stabilize each element. The polyvalent elements plutonium(IV) and iron(III) are found primarily as organic acid complexes, while the divalent elements nickel(II) and cadmium(II) are associated primarily with components of the amino acid/peptide fraction. For plutonium and cadmium, it was not possible to fully duplicate complexes formed in vivo by back reaction with whole exudates or individual class fractions, indicating the possible importance of plant induction processes, reaction kinetics, and/or the formation of mixed ligand complexes. The number and distribution of specific iron- and nickel-containing complexes varies with plant age and appears to be related to the relative concentration of organic acids and amino acids/peptides being produced and transported in the xylem as the plant matures. PMID:16665978

  10. Cadmium removal from wastewater by sponge iron sphere prepared by charcoal direct reduction.

    PubMed

    Li, Junguo; Li, Jun; Li, Yungang

    2009-01-01

    Sponge iron sphere (SIS), made of concentrated iron powder and possessed high activity and intension, was prepared through the process of palletizing, roasting and direct reduction by charcoal. The sponge iron sphere could remove most of Cd(2+) from wastewater. The results showed the Cd(2+) removal followed the first order reaction. Initial pH value played an important role in Cd(2+) removal. With original initial pH, Cd(2+) removal decreased to the minimum and then increased slightly with the rising of original concentration. The removal rate constant was -0.1263 and -0.0711 h(-1), respectively, under the Cd(2+) concentration of 50 and 200 mg/L. When the initial pH was adjusted to 3.0, the removal rate constant could increase to -9.896 and -4.351 h(-1), respectively. The removal percentage almost reached to 100% when Cd(2+) concentration was below 100 mg/L. While Cd(2+) concentration was above 100 mg/L, Cd(2+) removal percentage decreased slightly. In dynamic experiments, the column filled with sponge iron sphere exhibited favorable permeability. There was no sphere pulverization and conglutination between spheres. In contrast to the static state experiments, the Cd(2+) removal percentage in dynamic state experiment was lower, and the removal Cd(2+) quantity was 1.749 mg/g. PMID:25084434

  11. Migration of iron, lead, cadmium and tin from tinplate-coated cans into chickpeas.

    PubMed

    Kassouf, A; Chebib, H; Lebbos, N; Ouaini, R

    2013-01-01

    Migration studies of trace metals were carried out on coated chickpea cans marketed in Lebanon. Four elements--(Fe), tin (Sn), lead (Pb) and cadmium (Cd)--were analysed by atomic absorption spectrometry (AAS) after microwave digestion. Over 3 months, three different storage temperatures (5°C, room temperature and 40°C) were tested. In all cases, the migration of Fe reached a plateau after around 50 days of storage, while the migration of Pb was slow till 50 days, then it increased rapidly. Cd and Sn levels did not increase. Moreover, no effect of temperature was observed in the case of Fe, whereas Pb levels showed slower migration in cans stored at 5°C. Comparing cans from different chickpea brands (Lebanese and foreign) showed that the characteristics of the container have an effect on metal release. PMID:24059695

  12. Expression profiling reveals functionally redundant multiple-copy genes related to zinc, iron and cadmium responses in Brassica rapa.

    PubMed

    Li, Jimeng; Liu, Bo; Cheng, Feng; Wang, Xiaowu; Aarts, Mark G M; Wu, Jian

    2014-07-01

    Genes underlying environmental adaptability tend to be over-retained in polyploid plant species. Zinc deficiency (ZnD) and iron deficiency (FeD), excess Zn (ZnE) and cadmium exposure (CdE) are major environmental problems for crop cultivation, but little is known about the differential expression of duplicated genes upon these stress conditions. Applying Tag-Seq technology to leaves of Brassica rapa grown under FeD, ZnD, ZnE or CdE conditions, with normal conditions as a control, we examined global gene expression changes and compared the expression patterns of multiple paralogs. We identified 812, 543, 331 and 447 differentially expressed genes under FeD, ZnD, ZnE and CdE conditions, respectively, in B. rapa leaves. Genes involved in regulatory networks centered on the transcription factors bHLH038 or bHLH100 were differentially expressed under (ZnE-induced) FeD. Further analysis revealed that genes associated with Zn, Fe and Cd responses tended to be over-retained in the B. rapa genome. Most of these multiple-copy genes showed the same direction of expression change under stress conditions. We conclude that the duplicated genes involved in trace element responses in B. rapa are functionally redundant, making the regulatory network more complex in B. rapa than in Arabidopsis thaliana. PMID:24738937

  13. Splicing factor SR34b mutation reduces cadmium tolerance in Arabidopsis by regulating iron-regulated transporter 1 gene.

    PubMed

    Zhang, Wentao; Du, Bojing; Liu, Di; Qi, Xiaoting

    2014-12-12

    Serine/arginine-rich (SR) proteins are important splicing factors. However, the biological functions of plant SR proteins remain unclear especially in abiotic stresses. Cadmium (Cd) is a non-essential element that negatively affects plant growth and development. In this study, we provided clear evidence for SR gene involved in Cd tolerance in planta. Systemic expression analysis of 17 Arabidopsis SR genes revealed that SR34b is the only SR gene upregulated by Cd, suggesting its potential roles in Arabidopsis Cd tolerance. Consistent with this, a SR34b T-DNA insertion mutant (sr34b) was moderately sensitive to Cd, which had higher Cd(2+) uptake rate and accumulated Cd in greater amounts than wild-type. This was due to the altered expression of iron-regulated transporter 1 (IRT1) gene in sr34b mutant. Under normal growth conditions, IRT1 mRNAs highly accumulated in sr34b mutant, which was a result of increased stability of IRT1 mRNA. Under Cd stress, however, sr34b mutant plants had a splicing defect in IRT1 gene, thus reducing the IRT1 mRNA accumulation. Despite of this, sr34b mutant plants still constitutively expressed IRT1 proteins under Cd stress, thereby resulting in Cd stress-sensitive phenotype. We therefore propose the essential roles of SR34b in posttranscriptional regulation of IRT1 expression and identify it as a regulator of Arabidopsis Cd tolerance. PMID:25446093

  14. MANGANESE--1999 49.1 By Thomas S. Jones

    E-print Network

    Torgersen, Christian

    MANGANESE--1999 49.1 MANGANESE By Thomas S. Jones Domestic survey data and tables were prepared. Wallace, international data coordinators. Manganese (Mn) is essential to iron and steel production component, has accounted for most domestic manganese demand, presently in the range of 85% to 90

  15. MANGANESE--2000 50.1 By Thomas S. Jones

    E-print Network

    Torgersen, Christian

    MANGANESE--2000 50.1 MANGANESE By Thomas S. Jones Domestic survey data and tables were prepared. Wallace, international data coordinator. Manganese (Mn) is essential to iron and steel production component, has accounted for most domestic manganese demand, presently in the range of 85% to 90

  16. MANGANESE--2001 49.1 By Lisa A. Corathers

    E-print Network

    Torgersen, Christian

    MANGANESE--2001 49.1 MANGANESE By Lisa A. Corathers Domestic survey data and tables were prepared. Wallace, international data coordinator. Manganese is essential to iron and steel production by virtue component, has accounted for most domestic manganese demand, presently in the range of 85% to 90

  17. MANGANESE--1998 49.1 By Thomas S. Jones

    E-print Network

    Torgersen, Christian

    MANGANESE--1998 49.1 MANGANESE By Thomas S. Jones Domestic survey data and tables were prepared. Wallace, international data coordinator. Manganese is essential to iron and steel production by virtue component, has accounted for most domestic manganese demand, presently in the range of 85% to 90

  18. Occupational Exposure to Welding Fume among Welders: Alterations of Manganese, Iron, Zinc, Copper, and Lead in Body Fluids and the Oxidative Stress Status

    PubMed Central

    Li, Guojun Jane; Zhang, Long-Lian; Lu, Ling; Wu, Ping; Zheng, Wei

    2014-01-01

    Welders in this study were selected from a vehicle manufacturer; control subjects were from a nearby food factory. Airborne manganese levels in the breathing zones of welders and controls were 1.45 ± SD1.08 mg/m3 and 0.11 ± 0.07 ?g/m3, respectively. Serum levels of manganese and iron in welders were 4.3-fold and 1.9-fold, respectively, higher than those of controls. Blood lead concentrations in welders increased 2.5-fold, whereas serum zinc levels decreased 1.2-fold, in comparison with controls. Linear regression revealed the lack of associations between blood levels of five metals and welder’s age. Furthermore, welders had erythrocytic superoxide dismutase activity and serum malondialdehyde levels 24% less and 78% higher, respectively, than those of controls. These findings suggest that occupational exposure to welding fumes among welders disturbs the homeostasis of trace elements in systemic circulation and induces oxidative stress. PMID:15091287

  19. Cadmium removal from wastewater by sponge iron sphere prepared by hydrogen reduction.

    PubMed

    Li, Junguo; Wei, Linghong; Li, Yungang; Bi, Na; Song, Fangfang

    2011-06-01

    A new type of sponge iron sphere (NSIS) with 1-5 mm diameter, made of concentrated iron powder and possessed high activity and intension, was prepared by mini-pellet sintering integrated with H2 direct reduction. Static state experiment has been carried on to investigate the Cd(2+) removal efficiency from wastewater by the NSIS and to explore the Cd(2+) removal reaction kinetics. It was suggested that initial pH value and Cd(2+) original concentration had significant influence on Cd(2+) removal percentage. Cd(2+) removal percentage decreased significantly with the increasing of Cd(2+)original concentration whether the original pH value be adjusted to 3.0 or without adjustment. The results showed that the Cd(2+) removal process followed the first order reaction because the reaction order was from 0.803 to 0.996. The apparent reaction rate constant between Cd(2+) and NSIS was from 0.0025 to 0.1000 (mg·L(-1))(1-n)·min(-1). Compared with SIS reduced by charcoal reduction, NSIS deoxided by hydrogen possessed higher activity, and could remove the same quantity of Cd(2+) within a shorter period of time. PMID:25084570

  20. A binary AxB1-x ionic alkaline pseudocapacitor system involving manganese, iron, cobalt, and nickel: formation of electroactive colloids via in situ electric field assisted coprecipitation

    NASA Astrophysics Data System (ADS)

    Chen, Kunfeng; Yin, Shu; Xue, Dongfeng

    2014-12-01

    A new ``combinatorial transition-metal cation pseudocapacitor'' was demonstrated by designing combinatorial transition-metal cation pseudocapacitors with binary AxB1-x salt electrodes involving manganese, iron, cobalt, and nickel cations in an alkaline aqueous electrolyte. Binary multi-valence cations were crystallized in the colloidal state through an in situ coprecipitation under an electric field. These electroactive colloids absorbed by carbon black and the PVDF matrix are highly redox-reactive with high specific capacitance values, where the specific electrode configuration can create short ion diffusion paths to enable fast and reversible Faradaic reactions. This work shows huge promise for developing high-performance electrical energy storage systems via designing the colloidal state of electroactive cations. Multiple redox cations in the colloidal state can show high redox activities, making them more suitable for potential application in pseudocapacitor systems.A new ``combinatorial transition-metal cation pseudocapacitor'' was demonstrated by designing combinatorial transition-metal cation pseudocapacitors with binary AxB1-x salt electrodes involving manganese, iron, cobalt, and nickel cations in an alkaline aqueous electrolyte. Binary multi-valence cations were crystallized in the colloidal state through an in situ coprecipitation under an electric field. These electroactive colloids absorbed by carbon black and the PVDF matrix are highly redox-reactive with high specific capacitance values, where the specific electrode configuration can create short ion diffusion paths to enable fast and reversible Faradaic reactions. This work shows huge promise for developing high-performance electrical energy storage systems via designing the colloidal state of electroactive cations. Multiple redox cations in the colloidal state can show high redox activities, making them more suitable for potential application in pseudocapacitor systems. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr05880a

  1. Manganese recycling in the United States in 1998

    USGS Publications Warehouse

    Jones, Thomas S.

    2001-01-01

    This report describes the flow and processing of manganese within the U.S. economy in 1998 with emphasis on the extent to which manganese is recycled. Manganese was used mostly as an alloying agent in alloys in which it was a minor component. Manganese was recycled mostly within scrap of iron and steel. A small amount was recycled within aluminum used beverage cans. Very little manganese was recycled from materials being recovered specifically for their manganese content. For the United States in 1998, 218,000 metric tons of manganese was estimated to have been recycled from old scrap, of which 96% was from iron and steel scrap. Efficiency of recycling was estimated as 53% and recycling rate as 37%. Metallurgical loss of manganese was estimated to be about 1.7 times that recycled. This loss was mostly into slags from iron and steel production, from which recovery of manganese has yet to be shown economically feasible.

  2. Selective hydroxylation of cyclic ethers with tert-butylhydroperoxide and hydrogen peroxide catalyzed by iron(III) and manganese(II) bipyridine complexes included in zeolite Y and bentonite

    Microsoft Academic Search

    M Salavati Niassary; F Farzaneh; M Ghandi

    2001-01-01

    The oxidation of cyclic ethers such as tetrahydrofuran (THF), tetrahydropyran (THP), 2,3-dihydropyran (DHP) and 1,4-dioxan (DO), with hydrogen peroxide (H2O2) and tert-butylhydroperoxide (TBHP) in the presence of iron(III) and manganese(II) bipyridine complexes included in zeolite Y and bentonite are described. The products are mainly cyclic ether-2-ols and cyclic ether-2-ones with minor amounts of 2,3-dihydrocyclic ether.

  3. 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.

    PubMed

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

    2015-03-01

    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. PMID:25234328

  4. 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

    PubMed Central

    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. PMID:25234328

  5. Mineral of the month: manganese

    USGS Publications Warehouse

    Corathers, Lisa

    2005-01-01

    Manganese is one of the most important ferrous metals and one of the few for which the United States is totally dependent on imports. It is a black, brittle element predominantly used in metallurgical applications as an alloying addition, particularly in steel and cast iron production, which together provide the largest market for manganese (about 83 percent). It is also used as an alloy with nonferrous metals such as aluminum and copper. Nonmetallurgical applications of manganese include battery cathodes, soft ferrite magnets used in electronics, micronutrients found in fertilizers and animal feed, water treatment chemicals, and a colorant for bricks and ceramics.

  6. Influence of diagenetic processes in Thau lagoon on cadmium behavior and benthic fluxes

    NASA Astrophysics Data System (ADS)

    Metzger, E.; Simonucci, C.; Viollier, E.; Sarazin, G.; Prévot, F.; Elbaz-Poulichet, F.; Seidel, J.-L.; Jézéquel, D.

    2007-04-01

    DGT (Diffusive Gradient in Thin-films) and DET (Diffusive Equilibration in Thin-films) combined probes were used in Thau lagoon sediments to describe variations of dissolved concentrations of metals such as cadmium, manganese and iron, through the sediment-water interface. Two contrasted stations regarding organic carbon fluxes were studied from December 2001 to May 2003 during four field campaigns: station C4 in the middle of the lagoon, and station C5 in a shellfish-farming zone. Laboratory experiments and field deployments in such environment showed that DGT sampled pore water labile cadmium whereas iron and manganese concentrations were underestimated. These results suggest that no steady state in the flux of metals onto the gel was established for Fe and Mn. Kinetics of metal sulfide dissolution-precipitation may control metal fluxes onto the gel probe in marine sedimentary environments. Analysis of sediment and water column samples showed cadmium concentrations above natural background (3.3 and 7.6 nmol kg -1 for station C4 and station C5 sediments, respectively; between 40 and 800 pmol L -1 for the water column), suggesting contamination. Spatial and temporal patterns of cadmium behavior were observed. The sediment at station C4 was generally a source of cadmium whereas at station C5 it was a sink. The vertical extension of the diagenetic series was more important at station C4 with deeper oxygen penetration and lack of dissolved sulfide whereas station C5 showed steep ?H 2S gradients at the same depths. The data suggested that cadmium source was more likely organic matter. Cadmium mobility was probably controlled by aerobic mineralization at station C4 and by dissolution-precipitation of sulfides at station C5. Seasonal variations were observed in the depth of oxygen penetration and sulfide diffusion generating important remobilization of cadmium during December 2001. Conversely in May 2003 at station C5, bottom water suboxic conditions (i.e. %O 2 = 60) enhanced reductive conditions in the sediment favoring uptake of cadmium by the sediment from the water column.

  7. Manganese Intoxication

    PubMed Central

    Hine, Charles H.; Pasi, Aurelio

    1975-01-01

    We have reported two cases of chronic manganese poisoning. Case 1 followed exposure to manganese fumes in cutting and burning manganese steel. Case 2 resulted from exposure to dusts of manganese dioxide, an ingredient used in glazing of ceramics. There were initial difficulties in establishing the correct diagnosis. Prominent clinical features were severe and persistent chronic depressive psychosis (Case 1), transient acute brain syndrome (Case 2) and the presence of various extrapyramidal symptoms in both cases. Manganese intoxication has not previously been reported as occurring in California. With increasing use of the metal, the disease should be considered in the differential diagnosis of neurologic and psychiatric disease. Our observations were made in the period 1964 through 1968. Recently the prognosis of victims of manganese poisoning has been improved dramatically by the introduction of levodopa as a therapeutic agent. PMID:1179714

  8. pH-Responsive Iron Manganese Silicate Nanoparticles as T1-T2* Dual-Modal Imaging Probes for Tumor Diagnosis.

    PubMed

    Chen, Jian; Zhang, Wei-Jie; Guo, Zhen; Wang, Hai-Bao; Wang, Dong-Dong; Zhou, Jia-Jia; Chen, Qian-Wang

    2015-03-11

    Magnetic resonance imaging (MRI) probes can be concentrated in tumors through grafting targeting agents. However, the clinical application of such targeted MRI probes is largely limited because specific agents are only used to target specific characteristics of cancer cells. The development of the MRI probes that can be used regardless of tumor types or their developmental stages is highly appreciated. The acidic tumor microenvironments and acidic organelles (endosomes/lysosomes) in cancer cells are universal phenomena of solid tumors, and nanoparticles can also accumulate in tumor tissues by enhanced permeability and retention (EPR) effect. Here, we reported the synthesis of pH-responsive T1-T2* dual-modal contrast agents based on iron manganese silicate (FeMn(SiO4)) hollow nanospheres, which can release Mn(2+) ions in acidic environments, exhibiting excellent ability as agents for magnetic resonance and red fluorescence imaging. MRI for mouse models revealed that the nanoprobes could accumulate in tumors via EPR effect and then distinguish tumors from normal tissues with the synergistic effect of T1 and T2* signal only 10 min after intravenous injection. Fluorescence imaging demonstrated that the nanoprobes could be endocytosed into cancer cells and located at their lower pH compartments. Moreover, the hollow nanospheres showed no obvious toxicity and inflammation to the major organs of mice, which made them attractive diagnostic agents for different types of cancers. PMID:25685956

  9. Iron

    MedlinePLUS

    Iron is a mineral that our bodies need for many functions. For example, iron is part of hemoglobin, a protein which carries ... It helps our muscles store and use oxygen. Iron is also part of many other proteins and ...

  10. Chemical versus Enzymatic Digestion of Contaminated Estuarine Sediment: Relative Importance of Iron and Manganese Oxides in Controlling Trace Metal Bioavailability

    NASA Astrophysics Data System (ADS)

    Turner, A.; Olsen, Y. S.

    2000-12-01

    Chemical and enzymatic reagents have been employed to determine available concentrations of Fe, Mn, Cu and Zn in contaminated estuarine sediment. Gastric and intestinal enzymes (pepsin, pH 2, and trypsin, pH 7·6, respectively) removed significantly more metal than was water-soluble or exchangeable (by seawater or ammonium acetate), while gastro-intestinal fluid of the demersal teleost, Pleuronectes platessa L. (plaice), employed to operationally define a bioavailable fraction of contaminants, generally solubilized more metal than the model enzymes. Manganese was considerably more available than Fe under these conditions and it is suggested that the principal mechanism of contaminant release is via surface complexation and reductive solubilization of Mn oxides, a process which is enhanced under conditions of low pH. Of the chemical reagents tested, acetic acid best represents the fraction of Mn (as well as Cu and Zn) which is available under gastro-intestinal conditions, suggesting that the reducing tendency of acetate is similar to that of the ligands encountered in the natural digestive environment. Although the precise enzymatic and non-enzymatic composition of plaice gastro-intestinal fluid may be different to that encountered in more representative, filter-feeding or burrowing organisms, a general implication of this study is that contaminants associated with Mn oxides are significantly more bioavailable than those associated with Fe oxides, and that contaminant bioavailability may be largely dictated by the oxidic composition of contaminated sediment.

  11. Manganese nodules: thorium-230: protactinium-231 ratios.

    PubMed

    Sackett, W M

    1966-11-01

    The Th(230): Pa(231) activity ratio in 7 of 11 manganese nodules is less than 10.8, the theoretical production ratio of activities in the ocean. This finding indicates difierential accumulation of these nuclides in authigenic deposits of manganese-iron oxide. PMID:17778807

  12. High manganese concentrations in rocks at Gale crater, Mars

    E-print Network

    High manganese concentrations in rocks at Gale crater, Mars Nina L. Lanza1 , Woodward W. Fischer2 to iron, manganese is sensitive only to high redox potential oxidants, and when concentrated in rocks on the Curiosity rover indicate abundances of manganese in and on some rock targets that are 1­2 orders

  13. Co-overexpression FIT with AtbHLH38 or AtbHLH39 in Arabidopsis-enhanced cadmium tolerance via increased cadmium sequestration in roots and improved iron homeostasis of shoots.

    PubMed

    Wu, Huilan; Chen, Chunlin; Du, Juan; Liu, Hongfei; Cui, Yan; Zhang, Yue; He, Yujing; Wang, Yiqing; Chu, Chengcai; Feng, Zongyun; Li, Junming; Ling, Hong-Qing

    2012-02-01

    Cadmium (Cd) is toxic to plant cells. Under Cd exposure, the plant displayed leaf chlorosis, which is a typical symptom of iron (Fe) deficiency. Interactions of Cd with Fe have been reported. However, the molecular mechanisms of Cd-Fe interactions are not well understood. Here, we showed that FER-like Deficiency Induced Transcripition Factor (FIT), AtbHLH38, and AtbHLH39, three basic helix-loop-helix transcription factors involved in Fe homeostasis in plants, also play important roles in Cd tolerance. The gene expression analysis showed that the expression of FIT, AtbHLH38, and AtbHLH39 was up-regulated in the roots of plants treated with Cd. The plants overexpressing AtbHLH39 and double-overexpressing FIT/AtbHLH38 and FIT/AtbHLH39 exhibited more tolerance to Cd exposure than wild type, whereas no Cd tolerance was observed in plants overexpressing either AtbHLH38 or FIT. Further analysis revealed that co-overexpression of FIT with AtbHLH38 or AtbHLH39 constitutively activated the expression of Heavy Metal Associated3 (HMA3), Metal Tolerance Protein3 (MTP3), Iron Regulated Transporter2 (IRT2), and Iron Regulated Gene2 (IREG2), which are involved in the heavy metal detoxification in Arabidopsis (Arabidopis thaliana). Moreover, co-overexpression of FIT with AtbHLH38 or AtbHLH39 also enhanced the expression of NICOTIANAMINE SYNTHETASE1 (NAS1) and NAS2, resulting in the accumulation of nicotiananamine, a crucial chelator for Fe transportation and homeostasis. Finally, we showed that maintaining high Fe content in shoots under Cd exposure could alleviate the Cd toxicity. Our results provide new insight to understand the molecular mechanisms of Cd tolerance in plants. PMID:22184655

  14. Co-Overexpression FIT with AtbHLH38 or AtbHLH39 in Arabidopsis-Enhanced Cadmium Tolerance via Increased Cadmium Sequestration in Roots and Improved Iron Homeostasis of Shoots1[W

    PubMed Central

    Wu, Huilan; Chen, Chunlin; Du, Juan; Liu, Hongfei; Cui, Yan; Zhang, Yue; He, Yujing; Wang, Yiqing; Chu, Chengcai; Feng, Zongyun; Li, Junming; Ling, Hong-Qing

    2012-01-01

    Cadmium (Cd) is toxic to plant cells. Under Cd exposure, the plant displayed leaf chlorosis, which is a typical symptom of iron (Fe) deficiency. Interactions of Cd with Fe have been reported. However, the molecular mechanisms of Cd-Fe interactions are not well understood. Here, we showed that FER-like Deficiency Induced Transcripition Factor (FIT), AtbHLH38, and AtbHLH39, three basic helix-loop-helix transcription factors involved in Fe homeostasis in plants, also play important roles in Cd tolerance. The gene expression analysis showed that the expression of FIT, AtbHLH38, and AtbHLH39 was up-regulated in the roots of plants treated with Cd. The plants overexpressing AtbHLH39 and double-overexpressing FIT/AtbHLH38 and FIT/AtbHLH39 exhibited more tolerance to Cd exposure than wild type, whereas no Cd tolerance was observed in plants overexpressing either AtbHLH38 or FIT. Further analysis revealed that co-overexpression of FIT with AtbHLH38 or AtbHLH39 constitutively activated the expression of Heavy Metal Associated3 (HMA3), Metal Tolerance Protein3 (MTP3), Iron Regulated Transporter2 (IRT2), and Iron Regulated Gene2 (IREG2), which are involved in the heavy metal detoxification in Arabidopsis (Arabidopis thaliana). Moreover, co-overexpression of FIT with AtbHLH38 or AtbHLH39 also enhanced the expression of NICOTIANAMINE SYNTHETASE1 (NAS1) and NAS2, resulting in the accumulation of nicotiananamine, a crucial chelator for Fe transportation and homeostasis. Finally, we showed that maintaining high Fe content in shoots under Cd exposure could alleviate the Cd toxicity. Our results provide new insight to understand the molecular mechanisms of Cd tolerance in plants. PMID:22184655

  15. A strategy to improve the energy conversion efficiency and stability of quantum dot-sensitized solar cells using manganese-doped cadmium sulfide quantum dots.

    PubMed

    Gopi, Chandu V V M; Venkata-Haritha, M; Kim, Soo-Kyoung; Kim, Hee-Je

    2015-01-14

    This article describes the effect of manganese (Mn) doping in CdS to improve the photovoltaic performance of quantum dot sensitized solar cells (QDSSCs). The performances of the QDSSCs are examined in detail using a polysulfide electrolyte with a copper sulfide (CuS) counter electrode. Under the illumination of one sun (AM 1.5 G, 100 mW cm(-2)), 10 molar% Mn-doped CdS QDSSCs exhibit a power conversion efficiency (?) of 2.85%, which is higher than the value of 2.11% obtained with bare CdS. The improved photovoltaic performance is due to the impurities from Mn(2+) doping of CdS, which have an impact on the structure of the host material and decrease the surface roughness. The surface roughness and morphology of Mn-doped CdS nanoparticles can be characterised from atomic force microscopy images. Furthermore, the cell device based on the Mn-CdS electrode shows superior stability in the sulfide/polysulfide electrolyte in a working state for over 10 h, resulting in a highly reproducible performance, which is a serious challenge for the Mn-doped solar cell. Our finding provides an effective method for the fabrication of Mn-doped CdS QDs, which can pave the way to further improve the efficiency of future QDSSCs. PMID:25381887

  16. In vitro and in vivo corrosion properties of new iron-manganese alloys designed for cardiovascular applications.

    PubMed

    Drynda, Andreas; Hassel, Thomas; Bach, Friedrich Wilhelm; Peuster, Matthias

    2015-04-01

    The principle of biodegradation for the production of temporary implant materials (e.g. stents) plays an important role in the treatment of congenital heart defects. In the last decade several attempts have been made with different alloy materials-mainly based on iron and magnesium. None of the currently available materials in this field have demonstrated satisfying results and have therefore not found entry into broad clinical practice. While magnesium or magnesium alloy systems corrode too fast, the corrosion rate of pure iron-stents is too slow for cardiovascular applications. In the last years FeMn alloy systems were developed with the idea that galvanic effects, caused by different electrochemical properties of Fe and Mn, would increase the corrosion rate. In vitro tests with alloys containing up to 30% Mn showed promising results in terms of biocompatibility. This study deals with the development of new FeMn alloy systems with lower Mn concentrations (FeMn 0.5 wt %, FeMn 2.7 wt %, FeMn 6.9 wt %) to avoid Mn toxicity. Our results show, that these alloys exhibit good mechanical features as well as suitable in vitro biocompatibility and corrosion properties. In contrast, the evaluation of these alloys in a mouse model led to unexpected results-even after 9 months no significant corrosion was detectable. Preliminary SEM investigations showed that passivation layers (FeMn phosphates) might be the reason for corrosion resistance. If this can be proved in further experiments, strategies to prevent or dissolve those layers need to be developed to expedite the in vivo corrosion of FeMn alloys. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 649-660, 2015. PMID:24976236

  17. 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.

    PubMed

    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, 3?, n = 10) for undiluted blood samples were 2.0 ?g L(-1) for Al, 0.08 ?g L(-1) for Be, 0.10 ?g L(-1) for Cd, 2.2 ?g L(-1) for Cr, 7 ?g L(-1) for Hg, 0.4 ?g L(-1) for Mn, 2.3 ?g L(-1) for Ni, 3.4 ?g L(-1) for Pb, and 0.5 ?g 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. PMID:22868581

  18. Long-distance transport, vacuolar sequestration, tolerance, and transcriptional responses induced by cadmium and arsenic.

    PubMed

    Mendoza-Cózatl, David G; Jobe, Timothy O; Hauser, Felix; Schroeder, Julian I

    2011-10-01

    Iron, zinc, copper and manganese are essential metals for cellular enzyme functions while cadmium, mercury and the metalloid arsenic lack any biological function. Both, essential metals, at high concentrations, and non-essential metals and metalloids are extremely reactive and toxic. Therefore, plants have acquired specialized mechanisms to sense, transport and maintain essential metals within physiological concentrations and to detoxify non-essential metals and metalloids. This review focuses on the recent identification of transporters that sequester cadmium and arsenic in vacuoles and the mechanisms mediating the partitioning of these metal(loid)s between roots and shoots. We further discuss recent models of phloem-mediated long-distance transport, seed accumulation of Cd and As and recent data demonstrating that plants posses a defined transcriptional response that allow plants to preserve metal homeostasis. This research is instrumental for future engineering of reduced toxic metal(loid) accumulation in edible crop tissues as well as for improved phytoremediation technologies. PMID:21820943

  19. Long-distance transport, vacuolar sequestration and transcriptional responses induced by cadmium and arsenic

    PubMed Central

    Mendoza-Cózatl, David G.; Jobe, Timothy O.; Hauser, Felix; Schroeder, Julian I.

    2011-01-01

    Summary Iron, zinc, copper and manganese are essential metals for cellular enzyme functions while cadmium, mercury and the metalloid arsenic lack any biological function. Both, essential and non-essential metals and metalloids are extremely reactive and toxic. Therefore, plants have acquired specialized mechanisms to sense, transport and maintain essential metals within physiological concentrations and to detoxify non-essential metals and metalloids. This review focuses on the recent identification of transporters that sequester cadmium and arsenic in vacuoles and the mechanisms mediating the partitioning of these metal(loid)s between roots and shoots. We further discuss recent models of phloem-mediated long-distance transport, seed accumulation of Cd and As and recent data demonstrating that plants posses a defined transcriptional response that allow plants to preserve metal homeostasis. This research is instrumental for future engineering of reduced toxic metal(loid) accumulation in edible crop tissues as well as for improved phytoremediation technologies. PMID:21820943

  20. A Holocene record of endogenic iron and manganese precipitation and vegetation history in a lake-fen complex in northwestern Minnesota

    USGS Publications Warehouse

    Dean, W.E.; Doner, L.A.

    2012-01-01

    Little Shingobee Lake and Fen are part of the extensive network of lakes and wetlands in the Shingobee River headwaters of northwestern Minnesota, designed to study the interactions between surface and ground waters. Prior to about 11. 2 cal. ka, most of these lakes and wetlands were interconnected to form glacial Lake Willobee, which apparently formed when a debris flow dammed the Shingobee River. Between 11. 2 and 8. 5 cal. ka, the level of Lake Willobee fell as a result of breaching of the dam, transforming the deep lake into the existing lakes and wetlands. Analyses of a 9-m core from Little Shingobee Lake (LSL-B), and lacustrine sediments under 3. 3 m of peat in a 17-m core from Little Shingobee Fen (LSF-10), show that the dominant components are allogenic clastic material, and endogenic CaCO3 and organic matter. In both cores almost all of the iron (Fe) and manganese (Mn) are incorporated in endogenic minerals, presumed to be X-ray amorphous oxyhydroxide minerals, that occur in significant quantities throughout the cores; almost no Fe and Mn are contributed from detrital aluminosilicate minerals. This suggests that, for most of the Holocene, the allogenic watershed contributions to lake chemistry were minor compared to the dissolved mineral load. In addition, prior to 3. 5 cal. ka, pollen zone boundaries coincide with large changes in lake-sediment mineralogy, indicating that both landscape and climate processes were linked to early- and mid-Holocene lake chemistry. The pollen time series, with sequential domination by spruce, pine, sagebrush-oak, birch-oak and, finally, white pine is typical of the region and reflects the changing location of the prairie-forest transition zone over time. These changes in vegetation had some profound effects on the geochemistry of the lake waters. ?? 2011 Springer Science+Business Media B.V. (outside the USA).

  1. Removal and distribution of iron, manganese, cobalt, and nickel within a Pennsylvania constructed wetland treating coal combustion by-product leachate.

    PubMed

    Ye, Z H; Whiting, S N; Lin, Z Q; Lytle, C M; Qian, J H; Terry, N

    2001-01-01

    A flow-through wetland treatment system was constructed to treat coal combustion by-product leachate from an electrical power station at Springdale, Pennsylvania. In a nine-compartment treatment system, four cattail (Typha latifolia L.) wetland cells (designated Cells 1 through 4) successfully removed iron (Fe) and manganese (Mn) from the inlet water; Fe and Mn concentrations were decreased by an average of 91% in the first year (May 1996-May 1997), and by 94 and 98% in the second year (July 1997-June 1998), respectively. Cobalt (Co) and nickel (Ni) were decreased by an average of 39 and 47% in the first year, and 98 and 63% in the second year, respectively. Most of the metal removed by the wetland cells was accumulated in sediments, which constituted the largest sink. Except for Fe, metal concentrations in the sediments tended to be greater in the top 5 cm of sediment than in the 5- to 10- or 10- to 15-cm layers, and in Cell 1 than in Cells 2, 3, and 4. Plants constituted a much smaller sink for metals; only 0.91, 4.18, 0.19, and 0.38% of the Fe, Mn, Co, and Ni were accumulated annually in the aboveground tissues of cattail, respectively. A greater proportion of each metal (except Mn) was accumulated in cattail fallen litter and submerged Chara (a macroalga) tissues, that is, 2.81, 2.75, and 1.05% for Fe, Co, and Ni, respectively. Considerably higher concentrations of metals were associated with cattail roots than shoots, although Mn was a notable exception. PMID:11476526

  2. THE ROLE OF IRON IN Deinococcus radiodurans ENGINEERED FOR GROWTH ON TOLUENE AND THE ROLE OF MANGANESE IN THE EXTREME RADIATION RESISTANCE PHENOTYPE

    SciTech Connect

    Hassan Brim; Elena K. Gaidamakova; Vera Y. Matrosova; Min Zhai; Amudhan Venkateswaran; Marina Omelchenko; Kira S. Makarova; Lawrence P. Wackett; James K. Fredrickson; Michael J. Daly

    2004-03-17

    Toluene and other fuel hydrocarbons are commonly found in association with radionuclides at numerous Department of Energy (DOE) sites, frequently occurring together with Cr(VI) and other heavy metals. In this study, the extremely radiation resistant bacterium Deinococcus radiodurans was engineered for complete toluene mineralization by cloned expression of tod and xyl genes of Pseudomonas putida. The recombinant Tod/Xyl strain showed significant incorporation of carbon from the toluene aromatic ring into cellular macromolecules and carbon dioxide, in the absence or presence of chronic radiation. We have shown that intracellular iron concentrations in wild-type D. radiodurans in minimal medium are exceptionally low and not sufficient to support growth on toluene using Fe-dependent oxygenases cloned from P. putida. Introducing the fur mutation into D. radiodurans increased intracellular Fe levels, and imparted on the engineered strain the ability to grow on meta-toluate as the sole carbon and energy source. The organism's native Cr(VI) reduction capabilities were facilitated by toluene when present as the sole carbon and energy source in natural sediment analogues of DOE contaminated environments. The engineered bacteria were able to oxidize toluene under both minimal and complex nutrient conditions, which is important since both conditions have environmental equivalents in the context of bioremediation processes. As such, the Tod/Xyl strain is providing a model for understanding the role of Fe and reduction of metals coupled to organic contaminant oxidation in aerobic radionuclide contaminated sediments. We have shown that D. radiodurans contains high intracellular manganese levels, and that Mn restriction sensitizes cells to irradiation. We propose that the unusually high Mn/Fe ratio of D. radiodurans facilitates survival by quenching oxidative stress during recovery.

  3. Di-, tetra- and hexanuclear iron(III), manganese(II/III) and copper(II) complexes of Schiff-base ligands derived from 6-substituted-2-formylphenols.

    PubMed

    Lan, Yanhua; Novitchi, Ghenadie; Clérac, Rodolphe; Tang, Jin-Kui; Madhu, N T; Hewitt, Ian J; Anson, Christopher E; Brooker, Sally; Powell, Annie K

    2009-03-14

    Acyclic Schiff base ligands, derived from the condensation of 2,3-disubstituted benzaldehydes and 1,3-diaminopropan-2-ol, react with iron(II/III), manganese(II/III) and copper(II) salts to give di-, tetra- and hexanuclear complexes [Fe(III)(2)(L5)(2)].2MeOH (), [Fe(III)(4)(mu(3)-OMe)(2)(HL4)(2)Cl(2)] (), [Mn(II)(2)Mn(III)(2)(micro-OMe)(2)(HL4)(2)(DMF)(2)].2DMF () and [Cu(II)(6)(L5)(2)(micro(5)-SO(4))(2)(micro-SO(4))(MeOH)(2)].H(2)O.15.5(MeOH).15.5(MeCN) (). All compounds have been characterised by X-ray crystallography. Variable-temperature solid-state dc magnetisation studies have been performed in the temperature range 1.8-300 K. Antiferromagnetic interactions are present in all the compounds. The dinuclear compound has a zero total spin ground state with J = -9.66(1) cm(-1) and g = 2.07(1). The magnetic data for the tetranuclear compounds and have been interpreted using a tetranuclear butterfly model (b = body, w = wingtip) with the parameters: J(wb) = -9.35(4) cm(-1), J(bb) = -6.02(7) cm(-1), zJ' = -0.21(4) cm(-1) and g = 2.03(1) for ; and J(wb) = -3.40(3) cm(-1), J(bb) = -8.11(7) cm(-1), zJ' = -0.042(2) cm(-1) and g = 2.0 (fixed) for . The hexanuclear compound contains two {Cu(3)(L5)(MeOH)} units linked by three sulfate ligands: antiferromagnetic interactions are present in each trinuclear unit leading to two S = 1/2 motifs which do not or only very weakly interact across the sulfate bridges. PMID:19240905

  4. Influence of manganese incorporation on structure, surface and As(III)/As(V) removal capacity of iron oxy-hydroxides

    NASA Astrophysics Data System (ADS)

    Tresintsi, Sofia; Simeonidis, Konstantinos; Mitrakas, Manassis

    2013-04-01

    Iron oxy-hydroxides are well defined As(V) adsorbents dominating in water treatment market. The main drawback of these adsorbents, as well as of all commercial one, is their significantly low adsorption capacity for As(III). A breakthrough for improving As(III) adsorption of iron oxy-hydroxides may come by the MnO2incorporation. However, MnO2 decreases the total arsenic capacity proportionally to its percentage since its efficiency for As(V) is much lower than that of an iron oxy-hydroxide. It is concluded that an ideal adsorbent capable for high and simultaneous As(III) and As(V) removal should be consisted of a binary Fe(III)-Mn(IV) oxy-hydroxide both efficient for As(III) oxidation, due to Mn(IV) presence, and capture of As(V) due to a high positively surface charge density. This work studies the optimum parameters at the synthesis of single Fe and binary Fe/Mn oxy-hydroxides in a continuous flow kilogram-scale production reactor through the precipitation of FeSO4 in the pH range 3-12, under intense oxidative conditions using H2O2/KMnO4, that maximize arsenic adsorption. The evaluation of their efficiency was based on its As(III) and As(V) adsorption capacity (Q10-index) at equilibrium concentration equal to drinking water regulation limit (Ce= 10 ?g/L) in NSF challenge water. The pH of synthesis was found to decisively affect, the structure, surface configuration and Q10-index. As a result, both single Fe and binary Fe/Mn oxy-hydroxides prepared at pH 4, which consist of schwertmannite and Mn(IV)-feroxyhyte respectively, were qualified according to their highest Q10-index of 13±0.5 ?g As(V)/ mg for a residual arsenic concentration of 10 ?g/L at an equilibrium pH 7. The high surface charge and the activation of an ion-exchange mechanism between SO42- adsorbed in the Stern layer and arsenate ions were found to significantly contribute to the increased adsorption capacity. The Q10-index for As(III) of Fe/Mn adsorbent at equilibrium pH 7 was 6.7 ?g/mg, which is 3.5 times greater of that for single Fe one (1.9 ?g/mg), although it is significantly lower of the respective for As(V). However, Fe/Mn oxy-hydroxide present almost equal adsorption capacity for both arsenic species in the pH range 7.5-8. The As(III) adsorption capacity of Fe/Mn oxy-hydroxides is positively affected by the Mn content and the redox potential values at equilibrium pH 6-7. The corresponding Q10-index values observed in rapid scale column tests were in agreement with those of batch experiments, illustrating the improved efficiency of the qualified adsorbent compared to the common commercial arsenic adsorbents. Acknowledgement This work was supported by the European Commission FP7/Research for SMEs "AquAsZero", Project No: 232241.

  5. Localization and Role of Manganese Superoxide Dismutase in a Marine Diatom1[OA

    E-print Network

    Localization and Role of Manganese Superoxide Dismutase in a Marine Diatom1[OA] Felisa Wolfe-Simon2 by their metal cofactor (iron, manganese [Mn], copper/zinc, nickel), MnSOD is the dominant form in the diatom in four isoforms, recognized by their metal center cofactors (iron [Fe], manganese [Mn], copper [Cu

  6. IRON

    EPA Science Inventory

    The document surveys the effects of organic and inorganic iron that are relevant to humans and their environment. The biology and chemistry of iron are complex and only partially understood. Iron participates in oxidation reduction processes that not only affect its geochemical m...

  7. MODIFYING IRON REMOVAL PROCESSES TO INCREASE ARSENIC REMOVAL

    EPA Science Inventory

    Iron and manganese are naturally occurring substances that are normally found in insoluble forms in many ground waters in the US. Similar to iron and manganese, arsenic also occurs widely in the earth's crust and is a natural contaminant of many ground waters. Iron and manganese ...

  8. Application of VNIR diffuse reflectance spectroscopy to estimate soil organic carbon content, and content of different forms of iron and manganese

    NASA Astrophysics Data System (ADS)

    Klement, Ales; Jaksik, Ondrej; Kodesova, Radka; Drabek, Ondrej; Boruvka, Lubos

    2013-04-01

    Visible and near-infrared (VNIR) diffuse reflectance spectroscopy is a progressive method used for prediction of soil properties. Study was performed on the soils from the agricultural land from the south Moravia municipality of Brumovice. Studied area is characterized by a relatively flat upper part, a tributary valley in the middle and a colluvial fan at the bottom. Haplic Chernozem reminded at the flat upper part of the area. Regosols were formed at steep parts of the valley. Colluvial Chernozem and Colluvial soils were formed at the bottom parts of the valley and at the bottom part of the studied field. The goal of the study was to evaluate relationship between soil spectra curves and organic matter content, and different forms iron and manganese content (Mehlich III extract, ammonium oxalate extract and dithionite-citrate extract). Samples (87) were taken from the topsoil within regular grid covering studied area. The soil spectra curves (of air dry soil and sieved using 2 mm sieve) were measured in the laboratory using spectometer FieldSpec®3 (350 - 2 500 nm). The Fe and Mn contents in different extract were measured using ICP-OES (with an iCAP 6500 Radial ICP Emission spectrometer; Thermo Scientific, UK) under standard analytical conditions. Partial least squares regression (PLSR) was used for modeling of the relationship between spectra and measured soil properties. Prediction ability was evaluated using the R2, root mean square error (RMSE) and normalized root mean square deviation (NRMSD). The results showed the best prediction for Mn (R2 = 0.86, RMSE = 29, NRMSD = 0.11), Fe in ammonium oxalate extract (R2 = 0.82, RMSE = 171, NRMSD = 0.12) and organic matter content (R2 = 0.84, RMSE = 0.13, NRMSD = 0.09). The slightly worse prediction was obtained for Mn and Fe in citrate extract (R2 = 0.82, RMSE = 21, NRMSD = 0.10; R2 = 0.77, RMSE = 522, NRMSD = 0.23). Poor prediction was evaluated for Mn and Fe in Mehlich III extract (R2 = 0.43, RMSE = 13, NRMSD = 0.17; R2 = 0.39, RMSE = 13, NRMSD = 0.26). In general, the results confirmed that the measurement of soil spectral characteristics is a promising technology for a digital soil mapping and predicting studied soil properties. Acknowledgment: Authors acknowledge the financial support of the Ministry of Agriculture of the Czech Republic (grant No. QJ1230319) and the Czech Science Foundation (grant No. GA526/09/1762).

  9. Effect of manganese and zinc on the growth of Anacystis nidulans

    SciTech Connect

    Lee, L.H.; Lustigman, B.; Dandorf, D. (Montclair State College, Upper Montclair, NJ (United States))

    1994-07-01

    Anacystis nidulans is a unicellular member of the cyanobacteria, one of the largest groups of the Kingdom Monera. It is similar to other bacteria in the structure and chemistry of the cell wall, and its cell division and genetic recombination. Photoautotrophy is the main mode of nutrition and the photosynthetic apparatus is similar to that of other cyanobacteria. Cyanobacteria are excellent organisms to serve as environmental pollution indicators for the investigation of a wide variety of biological problems. There have been several studies on the effects of heavy metals on A. nidulans. Some of these elements, such as manganese, are known to be essential nutrients for cyanobacteria. Others, such as cadmium, are not known to be necessary for normal growth and metabolism. Large amounts of either essential or non-essential elements can be toxic. Manganese and zinc are essential elements for all living organisms. Manganese is a cofactor for a number of different enzymatic reactions particularly those involved in phosphorylation. Iron deficiency induced by a number of metals, cobalt and manganese in particular, inhibit chlorophyll biosynthesis. Zinc deficiency affects early mitotic events and the cells are large and aberrant in appearance. Light is essential for cells to take in zinc. As an industrial contaminant, zinc has been found to block photosynthesis by causing structural damage to the photosynthetic apparatus. In the presence of various pH ranges, high zinc concentrations can be associated with low pH. It has been indicated that pH value and EDTA (Ethylene Diamine Tetraacetic Acid) have an influence on the effect of some metals. The purpose of this study was to determine the effect of manganese and zinc on the growth of Anacystis nidulans, with and without EDTA.

  10. Cast B2-phase iron-aluminum alloys with improved fluidity

    DOEpatents

    Maziasz, Philip J. (122 Clark La., Oak Ridge, TN 37830); Paris, Alan M. (P.O. Box 64, Tarrs, PA 15688); Vought, Joseph D. (124 Cove Point Rd., Rockwood, TN 37854)

    2002-01-01

    Systems and methods are described for iron aluminum alloys. A composition includes iron, aluminum and manganese. A method includes providing an alloy including iron, aluminum and manganese; and processing the alloy. The systems and methods provide advantages because additions of manganese to iron aluminum alloys dramatically increase the fluidity of the alloys prior to solidification during casting.

  11. Simultaneous removal of cadmium and nitrate in aqueous media by nanoscale zerovalent iron (nZVI) and Au doped nZVI particles.

    PubMed

    Su, Yiming; Adeleye, Adeyemi S; Huang, Yuxiong; Sun, Xiaoya; Dai, Chaomeng; Zhou, Xuefei; Zhang, Yalei; Keller, Arturo A

    2014-10-15

    Nanoscale zerovalent iron (nZVI) has demonstrated high efficacy for treating nitrate or cadmium (Cd) contamination, but its efficiency for simultaneous removal of nitrate and Cd has not been investigated. This study evaluated the reactivity of nZVI to the co-contaminants and by-product formation, employed different catalysts to reduce nitrite yield from nitrate, and examined the transformation of nZVI after reaction. Nitrate reduction resulted in high solution pH, negatively charged surface of nZVI, formation of Fe3O4 (a stable transformation of nZVI), and no release of ionic iron. Increased pH and negative charge contributed to significant increase in Cd(II) removal capacity (from 40 mg/g to 188 mg/g) with nitrate present. In addition, nitrate reduction by nZVI could be catalyzed by Cd(II): while 30% of nitrate was reduced by nZVI within 2 h in the absence of Cd(II), complete nitrate reduction was observed in the presence of 40 mg-Cd/L due to the formation of Cd islands (Cd(0) and CdO) on the nZVI particles. While nitrate was reduced mostly to ammonium when Cd(II) was not present or at Cd(II) concentrations ? 40 mg/L, up to 20% of the initial nitrate was reduced to nitrite at Cd(II) concentrations < 40 mg/L. Among nZVI particles doped with 1 wt. % Cu, Ag, or Au, nZVI deposited with 1 wt. % Au reduced nitrite yield to less than 3% of the initial nitrate, while maintaining a high Cd(II) removal capacity. PMID:24999115

  12. Simultaneous coprecipitation of lead, cobalt, copper, cadmium, iron and nickel in food samples with zirconium(IV) hydroxide prior to their flame atomic absorption spectrometric determination.

    PubMed

    Citak, Demirhan; Tuzen, Mustafa; Soylak, Mustafa

    2009-09-01

    A simple and new coprecipitation procedure is developed for the determination of trace quantities of heavy metals (lead, cobalt, copper, cadmium, iron and nickel) in natural water and food samples. Analyte ions were coprecipitated by using zirconium(IV) hydroxide. The determination of metal levels was performed by flame atomic absorption spectrometry (FAAS). The influences of analytical parameters including pH, amount of zirconium(IV), sample volume, etc. were investigated on the recoveries of analyte ions. The effects of possible matrix ions were also examined. The recoveries of the analyte ions were in the range of 95-100%. Preconcentration factor was calculated as 25. The detection limits for the analyte ions based on 3 sigma (n=21) were in the range of 0.27-2.50 microgL(-1). Relative standard deviation was found to be lower than 8%. The validation of the presented coprecipitation procedure was performed by the analysis certified reference materials (GBW 07605 Tea and LGC 6010 Hard drinking water). The procedure was successfully applied to natural waters and food samples like coffee, fish, tobacco, black and green tea. PMID:19539005

  13. Structural Features of Manganese Precipitating Bacteria

    NASA Astrophysics Data System (ADS)

    Nealson, Kenneth H.; Tebo, Bradley

    1980-06-01

    Studies of biological communities of the past (and their associated activities) are usually dependent upon preservation of fossil material. With bacteria this rarely occurs because of the absence of sufficient fossilizable cellular material. However, some bacteria deposit metabolic products that can, conditions allowing, be preserved indefinitely. In particular, manganese and iron depositing bacteria have the capacity to form preservable microfossils. In order to better understand these microfossils of the past, we have examined present day morphologies of manganese oxidizing bacteria. These bacteria are highly pleomorphic, depending on the growth medium, the age of the culture, and the extent of manganese oxidation. Transmission electron microscopy indicates that manganese may be deposited either intra-or extra-cellularly. The prognosis of the use of morphological information for the interpretation of ancient and modern manganese deposits is discussed.

  14. Appl. Magn. Reson. 21, 413#424 (2001) Assignment of EPR Transitions in a Manganese-Containing

    E-print Network

    Ronquist, Fredrik

    Appl. Magn. Reson. 21, 413#424 (2001) Assignment of EPR Transitions in a Manganese of lipoxygenases, one containing manganese instead of iron, is character- ized by electron paramagnetic resonance manganese, instead of the usual iron, has been characterized enzymatically and by initial X-band EPR studies

  15. Relation of arsenic, iron, and manganese in ground water to aquifer type, bedrock lithogeochemistry, and land use in the New England coastal basins

    USGS Publications Warehouse

    Ayotte, Joseph D.; Nielsen, Martha G.; Robinson, Gilpin R.; Moore, Richard B.

    1999-01-01

    In a study of arsenic concentrations in public-supply wells in the New England Coastal Basins, concentrations at or above 0.005 mg/L (milligrams per liter) were detected in more samples of water from wells completed in bedrock (25 percent of all samples) than in water from wells completed in stratified drift (7.5 percent of all samples). Iron and manganese were detected (at concentrations of 0.05 and 0.03 mg/L, respectively) at approximately the same frequency in water from wells in both types of aquifers. Concentrations of arsenic in public-supply wells drilled in bedrock (in the National Water-Quality Assessment Program New England Coastal Basins study unit) vary with the bedrock lithology. Broad groups of lithogeochemical units generalized from bedrock lithologic units shown on state geologic maps were used in the statistical analyses. Concentrations of arsenic in water from public-supply wells in metasedimentary bedrock units that contain slightly to moderately calcareous and calcsilicate rocks (lithogeochemical group Mc) were significantly higher than the concentrations in five other groups of bedrock units in the study unit. Arsenic was detected, at or above 0.005 mg/L, in water from 44 percent of the wells in the lithogeochemical group M c and in water from less than 28 percent of wells in the five other groups. Additionally, arsenic concentrations in ground water were the lowest in the metasedimentary rocks that are characterized as variably sulfidic (group Ms ). Generally, concentrations of arsenic were low in water from bedrock wells in the felsic igneous rocks (group If ) though locally some bedrock wells in granitic rocks are known to have ground water with high arsenic concentrations, especially in New Hampshire. The concentrations of arsenic in ground water also correlate with land-use data; significantly higher concentrations are found in areas identified as agricultural land use than in undeveloped areas. There is, however, more agricultural land in areas overlying the metasedimentary rocks of lithogeochemical groups Mc and the minimally-deformed clastic sediments of group Mmd than in areas overlying other lithogeochemical groups. This correlation complicates the interpretation of sources of arsenic to ground water in bedrock. A test of this association revealed that relations between arsenic concentrations and the metasedimentary rocks of group Mc are not weakened when data associated with agricultural land use is removed; the reverse is true, however, if the data associated with the group Mc are removed from the analysis. The occurrence and variability of arsenic in water from bedrock supply wells could be related to several factors. These include (1) the distribution and chemical form of arsenic in soils and rocks that are part of the ground-water-flow system, (2) the characteristics that influence the solubility and transport of arsenic in ground water, (3) the differing degrees of vulnerability of ground-water supplies to surface contamination, and (4) the spatial associations between land use, geology, and ground-water-flow patterns. Strong relations between agricultural land use and the metasedimentary rocks of group Mc complicate the interpretation of arsenic source to water in these bedrock aquifers. This is due in part to the past use of arsenical pesticides; additionally, few whole-rock geochemical data are available for the rock types in the lithogeochemical groups of aquifers that contain ground water with elevated concentrations of arsenic. Without such data, identifying specific bedrock types as arsenic sources is not possible. In southern Maine and south-central New Hampshire, and in northern Massachusetts, the few available whole-rock analyses suggest, at least for these local areas, a connection between known bedrock chemistry and ground-water arsenic levels. Although the lithogeochemical group and land-use category variables individually describe much of the variance in the concentrations of

  16. A Holocene record of endogenic iron and manganese precipitation, isotopic composition of endogenic carbonate, and vegetation history in a lake-fen complex in northwestern Minnesota

    USGS Publications Warehouse

    Dean, Walter E.; Doner, Lisa A.

    2011-01-01

    Little Shingobee Lake and Fen are part of an extensive network of lakes and wetlands in the Shingobee River headwaters area of northwestern Minnesota. Prior to about 9800 radiocarbon years, most of the lakes in the Shingobee watershed area were interconnected to form glacial Lake Willobee. From 9800 to 7700 radiocarbon years, the level of Lake Willobee fell as a result of breaching of a dam, leaving small separated basins containing the existing lakes and wetlands. The dominant components in the sediments in a 9-meter core from Little Shingobee Lake (LSL-B), and lacustrine sediments under 3.3 meters of peat in a 17-meter core from Little Shingobee Fen (LSF-10) are detrital clastic material, endogenic CaCO3, and organic matter. The detrital fraction in the Holocene section in core LSL-B varies considerably from 7 weight percent to 82 weight percent and closely parallels the concentration of detrital quartz measured by X-ray diffraction. The CaCO3 concentration, which also varies considerably from 10 weight percent to 70 weight percent, is generally antithetic to the detrital concentration owing to the dilution of detrital material by CaCO3, particularly during the early to middle Holocene (about 9000-6500 calendar years). The organic-matter content varies from 5 weight percent to 25 weight percent and, together with CaCO3, serves to dilute the allogenic detrital fraction. In both cores almost all of the iron (Fe) and manganese (Mn) is in endogenic minerals, presumed to be oxyhydroxide minerals, that are important components throughout the core; little Fe and Mn are contributed by detrital aluminosilicate minerals. The endogenic Fe mineral, calculated as Fe(OH)3, forms a larger percentage of the sediment than endogenic organic material throughout most of the Holocene section in the LSL-B core and in the lacustrine sediments below the peat in the LSF-10 core. Biogenic silica as opal (biopal; diatom debris) was not measured, but the average calculated biopal is 5 percent in the LSL-B core and 15.5 percent in the LSF-10 core. Values of delta18O in mollusk (Pisidium) and ostracode shells increase by only about 20 per mil from the bottom to the top of the LSL-B core (about 12600-2200 calendar years). The remarkably constant oxygen-isotope composition throughout the Holocene suggests that environmental conditions affecting values of delta18O (temperature, salinity, composition of the water, composition of precipitation) did not change greatly. Values of delta13C in carbonate shells generally decreased by about 2 per mil from 9000 calendar years to 6000 calendar years, but they did not increase in organic carbon. This mid-Holocene increase in delta13C in shells but not in organic carbon is likely due to an increase in residence time. A late Pleistocene forest dominated by spruce was replaced in the early Holocene by a pine forest. The pine forest migrated east during the middle Holocene and was replaced by an open sagebrush-oak savanna. The western migration of forests into northwestern Minnesota is marked first by a hardwood forest and finally a pine forest.

  17. Determination of iron, cobalt, nickel, manganese, zinc, copper, cadmium and lead in human hair by inductively coupled plasma-atomic emission spectrometry

    NASA Astrophysics Data System (ADS)

    Sreenivasa Rao, K.; Balaji, T.; Prasada Rao, T.; Babu, Y.; Naidu, G. R. K.

    2002-08-01

    A method was standardized for the dissolution of hair samples and analysis was carried out by inductively coupled plasma atomic emission spectrometry (ICP-AES). Hair samples were brought into solution by using a mixture of nitric acid and hydrogen peroxide. Various parameters that influence the sample preparation, namely temperature, digestion time and ratio of acid mixture were studied and standardized. The optimized method has been employed to digest standard reference materials and hair samples of residents of India, collected from different age groups and sex, and analyzed for Fe, Co, Ni, Mn, Zn, Cu, Cd and Pb. The values agree for most of the metals with the data reported for human hair samples of residents of India. The NIES CRM Human Hair No. 5 and IAEA Reference Hair HH-1 certified reference materials were used in order to verify the accuracy of the method and the results were in excellent agreement with the certified values.

  18. Iron and Steel Phosphate Rock

    E-print Network

    Torgersen, Christian

    Phosphate Rock Platinum Potash Pumice Quartz Crystal Rare Earths Rhenium Rubidium Salt Sand and Gravel Cadmium Iodine Pumice Thorium Cement Iron Ore Quartz Crystal Tin Cesium Iron and Steel Rare Earths

  19. Inhibitory effect of dissolved silica on H?O? decomposition by iron(III) and manganese(IV) oxides: implications for H?O?-based in situ chemical oxidation.

    PubMed

    Pham, Anh Le-Tuan; Doyle, Fiona M; Sedlak, David L

    2012-01-17

    The decomposition of H(2)O(2) on iron minerals can generate •OH, a strong oxidant that can transform a wide range of contaminants. This reaction is critical to In Situ Chemical Oxidation (ISCO) processes used for soil and groundwater remediation, as well as advanced oxidation processes employed in waste treatment systems. The presence of dissolved silica at concentrations comparable to those encountered in natural waters decreases the reactivity of iron minerals toward H(2)O(2), because silica adsorbs onto the surface of iron minerals and alters catalytic sites. At circumneutral pH values, goethite, amorphous iron oxide, hematite, iron-coated sand, and montmorillonite that were pre-equilibrated with 0.05-1.5 mM SiO(2) were significantly less reactive toward H(2)O(2) decomposition than their original counterparts, with the H(2)O(2) loss rates inversely proportional to SiO(2) concentrations. In the goethite/H(2)O(2) system, the overall •OH yield, defined as the percentage of decomposed H(2)O(2) producing •OH, was almost halved in the presence of 1.5 mM SiO(2). Dissolved SiO(2) also slowed H(2)O(2) decomposition on manganese(IV) oxide. The presence of dissolved SiO(2) results in greater persistence of H(2)O(2) in groundwater and lower H(2)O(2) utilization efficiency and should be considered in the design of H(2)O(2)-based treatment systems. PMID:22129132

  20. Inhibitory Effect of Dissolved Silica on the H2O2 Decomposition by Iron(III) and Manganese(IV) Oxides: Implications for H2O2-based In Situ Chemical Oxidation

    PubMed Central

    Pham, Anh Le-Tuan; Doyle, Fiona M.; Sedlak, David L.

    2011-01-01

    The decomposition of H2O2 on iron minerals can generate •OH, a strong oxidant that can transform a wide range of contaminants. This reaction is critical to In Situ Chemical Oxidation (ISCO) processes used for soil and groundwater remediation, as well as advanced oxidation processes employed in waste treatment systems. The presence of dissolved silica at concentrations comparable to those encountered in natural waters decreases the reactivity of iron minerals toward H2O2, because silica adsorbs onto the surface of iron minerals and alters catalytic sites. At circumneutral pH values, goethite, amorphous iron oxide, hematite, iron-coated sand and montmorillonite that were pre-equilibrated with 0.05 – 1.5 mM SiO2 were significantly less reactive toward H2O2 decomposition than their original counterparts, with the H2O2 loss rates inversely proportional to the SiO2 concentration. In the goethite/H2O2 system, the overall •OH yield, defined as the percentage of decomposed H2O2 producing •OH, was almost halved in the presence of 1.5 mM SiO2. Dissolved SiO2 also slows the H2O2 decomposition on manganese(IV) oxide. The presence of dissolved SiO2 results in greater persistence of H2O2 in groundwater, lower H2O2 utilization efficiency and should be considered in the design of H2O2-based treatment systems. PMID:22129132

  1. Assessment of in-plant particulate matter and its toxic metals contents of sponge iron industry in Goa, India.

    PubMed

    Gupta, R K; Bhanarkar, A D; Tamhane, S M; Dhopte, S M

    2010-12-01

    The present study attempted to assess toxic metal contents (Arsenic, Cadmium, Copper, Cobalt, Chromium, Iron, Manganese, Nickel, Lead and Zinc) in Total Suspended Particulate (TSP) and Particulate Matter less than ten micron (PM??) in three sponge iron industries in Goa (India), one of the famous tourist place on the World map. TSP and PM(10) average concentration in all three sponge iron industries were found to be in the range 401-485 ?g/m³ and 135-270 ?g/m³ respectively. Amongst all the metals, concentration of iron was the highest in TSP as well as in PM??. Statistical results indicate that proportion of specific metals were found higher in PM?? as compared to the ratio of PM??/TSP ratio. Value of correlation coefficient was found to be significant for Cr-Pb indicating coal burning was the major source contributor. PMID:21110186

  2. A binary A(x)B(1-x) ionic alkaline pseudocapacitor system involving manganese, iron, cobalt, and nickel: formation of electroactive colloids via in situ electric field assisted coprecipitation.

    PubMed

    Chen, Kunfeng; Yin, Shu; Xue, Dongfeng

    2015-01-21

    A new "combinatorial transition-metal cation pseudocapacitor" was demonstrated by designing combinatorial transition-metal cation pseudocapacitors with binary AxB1-x salt electrodes involving manganese, iron, cobalt, and nickel cations in an alkaline aqueous electrolyte. Binary multi-valence cations were crystallized in the colloidal state through an in situ coprecipitation under an electric field. These electroactive colloids absorbed by carbon black and the PVDF matrix are highly redox-reactive with high specific capacitance values, where the specific electrode configuration can create short ion diffusion paths to enable fast and reversible Faradaic reactions. This work shows huge promise for developing high-performance electrical energy storage systems via designing the colloidal state of electroactive cations. Multiple redox cations in the colloidal state can show high redox activities, making them more suitable for potential application in pseudocapacitor systems. PMID:25486527

  3. Cadmium in blood and urine--impact of sex, age, dietary intake, iron status, and former smoking--association of renal effects.

    PubMed

    Olsson, Ing-Marie; Bensryd, Inger; Lundh, Thomas; Ottosson, Helena; Skerfving, Staffan; Oskarsson, Agneta

    2002-12-01

    We studied determinants of cadmium status and kidney function in nonsmoking men and women living on farms in southern Sweden. Median blood Cd (BCd) was 1.8 nmol/L (range, 0.38-18) and median urinary Cd (UCd) was 0.23 nmol/mmol creatinine (range, 0.065-0.99). The intake of Cd per kilogram body weight did not significantly differ between sexes and did not correlate with BCd or UCd, which may be explained by a low and varying bioavailibility of Cd from food items. However, when a subgroup of the study population, couples of never-smoking men and women, were compared, a lower intake per kilogram body weight was found in the women, but the women had a 1.8 times higher BCd and a 1.4 times higher UCd. The higher female BCd and UCd may be explained by higher absorption due to low iron status. BCd and UCd both increased with age and were higher in the ex-smokers, who had stopped smoking more than 5 years before the study, compared to never-smokers. The contribution of locally produced food to the total Cd intake was relatively low and varied. Males living in areas with low soil Cd had lower UCd than the others. However, Cd levels in kidneys from pigs, fed locally produced cereals, did not predict BCd or UCd in humans at the same farms. The kidney function parameter ss2-microglobulin-creatinine clearance was related to UCd, whereas urinary protein-HC, N-acetyl-ss-glucoseaminidase or albumin-creatinine clearance was not when age was accounted for. Hence, even at the low exposure levels in this study population, there was an indication of effect on biochemical markers of renal function. PMID:12460796

  4. Iron, copper, zinc, and manganese transport and regulation in pathogenic Enterobacteria: correlations between strains, site of infection and the relative importance of the different metal transport systems for virulence

    PubMed Central

    Porcheron, Gaëlle; Garénaux, Amélie; Proulx, Julie; Sabri, Mourad; Dozois, Charles M.

    2013-01-01

    For all microorganisms, acquisition of metal ions is essential for survival in the environment or in their infected host. Metal ions are required in many biological processes as components of metalloproteins and serve as cofactors or structural elements for enzymes. However, it is critical for bacteria to ensure that metal uptake and availability is in accordance with physiological needs, as an imbalance in bacterial metal homeostasis is deleterious. Indeed, host defense strategies against infection either consist of metal starvation by sequestration or toxicity by the highly concentrated release of metals. To overcome these host strategies, bacteria employ a variety of metal uptake and export systems and finely regulate metal homeostasis by numerous transcriptional regulators, allowing them to adapt to changing environmental conditions. As a consequence, iron, zinc, manganese, and copper uptake systems significantly contribute to the virulence of many pathogenic bacteria. However, during the course of our experiments on the role of iron and manganese transporters in extraintestinal Escherichia coli (ExPEC) virulence, we observed that depending on the strain tested, the importance of tested systems in virulence may be different. This could be due to the different set of systems present in these strains, but literature also suggests that as each pathogen must adapt to the particular microenvironment of its site of infection, the role of each acquisition system in virulence can differ from a particular strain to another. In this review, we present the systems involved in metal transport by Enterobacteria and the main regulators responsible for their controlled expression. We also discuss the relative role of these systems depending on the pathogen and the tissues they infect. PMID:24367764

  5. Impact of two iron(III) chelators on the iron, cadmium, lead and nickel accumulation in poplar grown under heavy metal stress in hydroponics.

    PubMed

    Mihucz, Victor G; Csog, Árpád; Fodor, Ferenc; Tatár, Enik?; Szoboszlai, Norbert; Silaghi-Dumitrescu, Lumini?a; Záray, Gyula

    2012-04-15

    Poplar (Populus jacquemontiana var. glauca cv. Kopeczkii) was grown in hydroponics containing 10 ?M Cd(II), Ni(II) or Pb(II), and Fe as Fe(III) EDTA or Fe(III) citrate in identical concentrations. The present study was designed to compare the accumulation and distribution of Fe, Cd, Ni and Pb within the different plant compartments. Generally, Fe and heavy-metal accumulation were higher by factor 2-7 and 1.6-3.3, respectively, when Fe(III) citrate was used. Iron transport towards the shoot depended on the Fe(III) chelate and, generally, on the heavy metal used. Lead was accumulated only in the root. The amounts of Fe and heavy metals accumulated by poplar were very similar to those of cucumber grown in an identical way, indicating strong Fe uptake regulation of these two Strategy I plants: a cultivar and a woody plant. The Strategy I Fe uptake mechanism (i.e. reducing Fe(III) followed by Fe(II) uptake), together with the Fe(III) chelate form in the nutrient solution had significant effects on Fe and heavy metal uptake. Poplar appears to show phytoremediation potential for Cd and Ni, as their transport towards the shoot was characterized by 51-54% and 26-48% depending on the Fe(III) supply in the nutrient solution. PMID:22305049

  6. Manganese biofouling and the corrosion behavior of stainless steel

    Microsoft Academic Search

    W. H. Dickinson; Z. Lewandowski

    1996-01-01

    Manganese? and iron?oxidizing bacteria (MFOB) are widely implicated in microbially influenced corrosion, often in association with sulfate?reducing bacteria (SRB). Traditionally MFOB have been assigned a passive role in the corrosion process, promoting differential aeration cells, and providing oxygen depleted conditions conducive to the growth and corrosive attack of SRB. Recent work, summarized in this article, demonstrates that manganese biofouling alters

  7. The Experience and Limitations of using Manganese Alkaline Primary Cells in a large Operational AUV

    E-print Network

    Griffiths, Gwyn

    Cadmium · Nickel Metal Hydride · Silver Zinc · Lithium Ion Primary cells · Manganese Alkaline The approximate performance of these cells is listed in Table I. Nickel Cadmium cells have an energy density only-equipping Autosub with a new energy source, the principal battery options considered were: Secondary cells · Nickel

  8. Subchronic dietary exposure of rats to cadmium alters the metabolism of metals essential to bone health.

    PubMed

    Noël, L; Guérin, T; Kolf-Clauw, M

    2004-08-01

    Cadmium (Cd) was recently identified as a risk factor for osteoporosis. Skeletal damage may be the critical effect of low-level long-term exposure to Cd in the general population exposed via food, but the mechanisms behind this are not clearly understood. We investigated the effect of dietary Cd exposure on metals involved in bone turnover. Female rats received a Cd-supplemented diet (0, 10, 50, or 200 CdCl2 mg/kg diet) for 13 weeks. Cd and essential metals stored in the liver were measured by ICP-MS multianalysis. Mineral content of the livers was modified according to Cd level: iron, magnesium and selenium decreased while copper, zinc and manganese increased with increasing Cd levels. Iron was the most strikingly affected metal, falling to one-fifth of control values at high dietary Cd exposure. In this dosage group, selenium decreased to 36% of mean control concentrations while zinc increased to 168%. This mineral imbalance, especially depleted iron stores, can contribute, at least in part, to the Cd-associated risk of osteoporosis. The association between iron metabolism and Cd exposure should be investigated in humans, as Cd and low iron stores could act synergistically as risk factors for osteoporosis. PMID:15207369

  9. Cadmium toxicity

    PubMed Central

    Wan, Lichuan; Zhang, Haiyan

    2012-01-01

    Cadmium is a well-known environmental pollutant with distinctly toxic effects on plants. It can displace certain essential metals from a wealth of metalloproteins, and thus disturb many normal physiological processes and cause severe developmental aberrant. The harmful effects of cadmium stress include, but are not limited to: reactive oxygen species overproduction, higher lipid hydroperoxide contents, and chloroplast structure change, which may lead to cell death. Plants have developed diverse mechanisms to alleviate environmental cadmium stress, e.g., cadmium pump and transporting cadmium into the leaf vacuoles. This mini-review focuses on the current research into understanding the cellular mechanisms of cadmium toxicity on cytoskeleton, vesicular trafficking and cell wall formation in plants. PMID:22499203

  10. Dysregulation of transition metal ion homeostasis is the molecular basis for cadmium toxicity in Streptococcus pneumoniae.

    PubMed

    Begg, Stephanie L; Eijkelkamp, Bart A; Luo, Zhenyao; Couñago, Rafael M; Morey, Jacqueline R; Maher, Megan J; Ong, Cheryl-Lynn Y; McEwan, Alastair G; Kobe, Bostjan; O'Mara, Megan L; Paton, James C; McDevitt, Christopher A

    2015-01-01

    Cadmium is a transition metal ion that is highly toxic in biological systems. Although relatively rare in the Earth's crust, anthropogenic release of cadmium since industrialization has increased biogeochemical cycling and the abundance of the ion in the biosphere. Despite this, the molecular basis of its toxicity remains unclear. Here we combine metal-accumulation assays, high-resolution structural data and biochemical analyses to show that cadmium toxicity, in Streptococcus pneumoniae, occurs via perturbation of first row transition metal ion homeostasis. We show that cadmium uptake reduces the millimolar cellular accumulation of manganese and zinc, and thereby increases sensitivity to oxidative stress. Despite this, high cellular concentrations of cadmium (~17?mM) are tolerated, with negligible impact on growth or sensitivity to oxidative stress, when manganese and glutathione are abundant. Collectively, this work provides insight into the molecular basis of cadmium toxicity in prokaryotes, and the connection between cadmium accumulation and oxidative stress. PMID:25731976

  11. Dysregulation of transition metal ion homeostasis is the molecular basis for cadmium toxicity in Streptococcus pneumoniae

    PubMed Central

    Begg, Stephanie L.; Eijkelkamp, Bart A.; Luo, Zhenyao; Couñago, Rafael M.; Morey, Jacqueline R.; Maher, Megan J.; Ong, Cheryl-lynn Y.; McEwan, Alastair G.; Kobe, Bostjan; O’Mara, Megan L.; Paton, James C.; McDevitt, Christopher A.

    2015-01-01

    Cadmium is a transition metal ion that is highly toxic in biological systems. Although relatively rare in the Earth’s crust, anthropogenic release of cadmium since industrialization has increased biogeochemical cycling and the abundance of the ion in the biosphere. Despite this, the molecular basis of its toxicity remains unclear. Here we combine metal-accumulation assays, high-resolution structural data and biochemical analyses to show that cadmium toxicity, in Streptococcus pneumoniae, occurs via perturbation of first row transition metal ion homeostasis. We show that cadmium uptake reduces the millimolar cellular accumulation of manganese and zinc, and thereby increases sensitivity to oxidative stress. Despite this, high cellular concentrations of cadmium (~17?mM) are tolerated, with negligible impact on growth or sensitivity to oxidative stress, when manganese and glutathione are abundant. Collectively, this work provides insight into the molecular basis of cadmium toxicity in prokaryotes, and the connection between cadmium accumulation and oxidative stress. PMID:25731976

  12. Manganese deficiency in Chlamydomonas results in loss of photosystem II and MnSOD function, sensitivity to peroxides, and secondary phosphorus and iron deficiency.

    PubMed

    Allen, Michael D; Kropat, Janette; Tottey, Stephen; Del Campo, José A; Merchant, Sabeeha S

    2007-01-01

    For photoheterotrophic growth, a Chlamydomonas reinhardtii cell requires at least 1.7 x 10(7) manganese ions in the medium. At lower manganese ion concentrations (typically <0.5 microm), cells divide more slowly, accumulate less chlorophyll, and the culture reaches stationary phase at lower cell density. Below 0.1 microm supplemental manganese ion in the medium, the cells are photosynthetically defective. This is accompanied by decreased abundance of D1, which binds the Mn(4)Ca cluster, and release of the OEE proteins from the membrane. Assay of Mn superoxide dismutase (MnSOD) indicates loss of activity of two isozymes in proportion to the Mn deficiency. The expression of MSD3 through MSD5, encoding various isoforms of the MnSODs, is up-regulated severalfold in Mn-deficient cells, but neither expression nor activity of the plastid Fe-containing superoxide dismutase is changed, which contrasts with the dramatically increased MSD3 expression and plastid MnSOD activity in Fe-deficient cells. Mn-deficient cells are selectively sensitive to peroxide but not methyl viologen or Rose Bengal, and GPXs, APX, and MSRA2 genes (encoding glutathione peroxidase, ascorbate peroxidase, and methionine sulfoxide reductase 2) are slightly up-regulated. Elemental analysis indicates that the Mn, Fe, and P contents of cells in the Mn-deficient cultures were reduced in proportion to the deficiency. A natural resistance-associated macrophage protein homolog and one of five metal tolerance proteins were induced in Mn-deficient cells but not in Fe-deficient cells, suggesting that the corresponding gene products may be components of a Mn(2+)-selective assimilation pathway. PMID:17085511

  13. Biological manganese removal from acid mine drainage in constructed wetlands and prototype bioreactors

    Microsoft Academic Search

    Kevin B. Hallberg; D. Barrie Johnson

    2005-01-01

    Mine drainage waters vary considerably in the range and concentration of heavy metals they contain. Besides iron, manganese is frequently present at elevated concentrations in waters draining both coal and metal mines. Passive treatment systems (aerobic wetlands and compost bioreactors) are designed to remove iron by biologically induced oxidation\\/precipitation. Manganese, however, is problematic as it does not readily form sulfidic

  14. Spectroscopic characterization of manganese minerals.

    PubMed

    Lakshmi Reddy, S; Padma Suvarna, K; Udayabhaska Reddy, G; Endo, Tamio; Frost, R L

    2014-01-01

    Manganese minerals ardenite, alleghanyite and leucopoenicite originated from Madhya Pradesh, India, Nagano prefecture Japan, Sussex Country and Parker Shaft Franklin, Sussex Country, New Jersey respectively are used in the present work. In these minerals manganese is the major constituent and iron if present is in traces only. An EPR study of on all of the above samples confirms the presence of Mn(II) with g around 2.0. Optical absorption spectrum of the mineral alleghanyite indicates that Mn(II) is present in two different octahedral sites and in leucophoenicite Mn(II) is also in octahedral geometry. Ardenite mineral gives only a few Mn(II) bands. NIR results of the minerals ardenite, leucophoenicite and alleghanyite are due to hydroxyl and silicate anions which confirming the formulae of the minerals. PMID:23995604

  15. Magneto-Optical Study of Transition Metal Alloys CADMIUM(1-X) Cobalt(x) Telluride, CADMIUM(1-X) Iron(x) Selenide, COPPER(2) ZINC(1-X) Manganese(x) Germanium SILICIDE(4), and CADMIUM(1-X) Manganese(x) Telluride

    NASA Astrophysics Data System (ADS)

    Shih, Oliver William

    In diluted magnetic semiconductors (DMS's), the presence of transition metal ions with localized spin moments leads to enhanced magneto-optical (MO) effects. These effects arise from the sp-d exchange interaction between the band electrons and the localized 3d electrons. The sp-d exchange constants N_0alpha and N_0beta and the magnetization determine the size of these effects. This work describes a first-time MO investigation of the sp-d exchange interaction in the wide-gap DMS's Cd_{1-x}Co_ {x}Te, Cd_{1-x} Fe_{x}Se, and Cu _2Zn_{1-x} Mn_{x}GeS _4. The search for DMS's exhibiting larger MO effects motivated the study of these materials. Cd _{1-x}Co_ {x}Te and Cd_{1-x }Fe_{x}Se belong to the II-VI family of DMS's where a fraction of the group-II cation Cd^{2+} is replaced by Co^{2+} and Fe^{2+} respectively. Cu _2Zn_{1-x} Mn_{x}GeS _4 belongs to the I_2 -II-IV-VI_4 family of DMS's in which the Mn^{2+}-Mn ^{2+} antiferromagnetic interactions are weaker due to its wurtz-stannite crystal structure. The result is an order of magnitude larger magnetization than that observed in II-VI DMS's containing Mn^ {2+}. The strength of the exchange interaction for the above DMS's was determined from magnetoreflectance spectra and magnetization measures at T~eq 1.3 K and magnetic field B<= 15 T. We found that the quantity N_0 alpha-N_0beta for Cd _{1-x}Co_{x }Te and Cd_{1-x}Fe _{x}Se is ~ 50% larger than that of Cd_{1 -x}Mn_{x}Te and is an order of magnitude smaller for Cu_2 Zn_{1-x}Mn _{x}GeS_4. The anisotropy of N_0beta for Cd_{1-x}Fe_ {x}Se amounts to 4%. In the case of Cu _2Zn_{1-x} Mn_{x}GeS _4, we measured the anisotropy to be N _0beta_{z}-N_0beta _{x}~eq 35 meV. We also found that when x changes from 1.00 to 0.92, N _0alpha-N_0beta changes by ~13% which is rather large. This work also discusses a peculiar change in exciton lineshape observed in Cd_{1 -x}Mn_{x}Te magnetoreflectance spectra at high magnetic fields. This new feature is attributed to the hybridization between an excited state and the ground state of an exciton. A numerical model of exciton states in DMS's valid for degenerate valence bands and arbitrary magnetic fields is presented. Using a simplified set of basis functions, quantitative agreement with the data to within a factor of two was obtained. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253 -1690.).

  16. Enzymatic iron oxidation by Leptothrix discophora: identification of an iron-oxidizing protein.

    PubMed

    Corstjens, P L; de Vrind, J P; Westbroek, P; de Vrind-de Jong, E W

    1992-02-01

    An iron-oxidizing factor was identified in the spent culture medium of the iron- and manganese-oxidizing bacterial strain Leptothrix discophora SS-1. It appeared to be a protein, with an apparent molecular weight of approximately 150,000. Its activity could be demonstrated after fractionation of the spent medium by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A spontaneous mutant of L. discophora SS-1 was isolated which excreted neither manganese- nor iron-oxidizing activity, whereas excretion of other proteins seemed to be unaffected. Although the excretion of both metal-oxidizing factors was probably linked, the difference in other properties suggests that manganese and iron oxidation represent two different pathways. With a dot-blot assay, it was established that different bacterial species have different metal-oxidizing capacities. Whereas L. discophora oxidized both iron and manganese, Sphaerotilus natans oxidized only iron and two Pseudomonas spp. oxidized only manganese. PMID:1610168

  17. Enzymatic iron oxidation by Leptothrix discophora: identification of an iron-oxidizing protein.

    PubMed Central

    Corstjens, P L; de Vrind, J P; Westbroek, P; de Vrind-de Jong, E W

    1992-01-01

    An iron-oxidizing factor was identified in the spent culture medium of the iron- and manganese-oxidizing bacterial strain Leptothrix discophora SS-1. It appeared to be a protein, with an apparent molecular weight of approximately 150,000. Its activity could be demonstrated after fractionation of the spent medium by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A spontaneous mutant of L. discophora SS-1 was isolated which excreted neither manganese- nor iron-oxidizing activity, whereas excretion of other proteins seemed to be unaffected. Although the excretion of both metal-oxidizing factors was probably linked, the difference in other properties suggests that manganese and iron oxidation represent two different pathways. With a dot-blot assay, it was established that different bacterial species have different metal-oxidizing capacities. Whereas L. discophora oxidized both iron and manganese, Sphaerotilus natans oxidized only iron and two Pseudomonas spp. oxidized only manganese. Images PMID:1610168

  18. The Escherichia coli Small Protein MntS and Exporter MntP Optimize the Intracellular Concentration of Manganese

    PubMed Central

    Martin, Julia E.; Waters, Lauren S.; Storz, Gisela; Imlay, James A.

    2015-01-01

    Escherichia coli does not routinely import manganese, but it will do so when iron is unavailable, so that manganese can substitute for iron as an enzyme cofactor. When intracellular manganese levels are low, the cell induces the MntH manganese importer plus MntS, a small protein of unknown function; when manganese levels are high, the cell induces the MntP manganese exporter and reduces expression of MntH and MntS. The role of MntS has not been clear. Previous work showed that forced MntS synthesis under manganese-rich conditions caused bacteriostasis. Here we find that when manganese is scarce, MntS helps manganese to activate a variety of enzymes. Its overproduction under manganese-rich conditions caused manganese to accumulate to very high levels inside the cell; simultaneously, iron levels dropped precipitously, apparently because manganese-bound Fur blocked the production of iron importers. Under these conditions, heme synthesis stopped, ultimately depleting cytochrome oxidase activity and causing the failure of aerobic metabolism. Protoporphyrin IX accumulated, indicating that the combination of excess manganese and iron deficiency had stalled ferrochelatase. The same chain of events occurred when mutants lacking MntP, the manganese exporter, were exposed to manganese. Genetic analysis suggested the possibility that MntS exerts this effect by inhibiting MntP. We discuss a model wherein during transitions between low- and high-manganese environments E. coli uses MntP to compensate for MntH overactivity, and MntS to compensate for MntP overactivity. PMID:25774656

  19. Influence de l'addition de diffrentes matires fertilisantes sur la biodisponibilit du cadmium,

    E-print Network

    Paris-Sud XI, Université de

    cadmium, du manganèse, du nickel et du zinc contenus dans un sol sableux amendé par des boues de station d fer. SUMMARY Changes in the cadmium, manganese, nickel and zinc bioavailability ofa sewage sludge'interpréter l'action dépressive exercée sur la biodisponibilité du cadmium par la tourbe et surtout par les

  20. COLORIMETRIC DETERMINATION OF MANGANESE

    E-print Network

    Bertsch George F.

    1 COLORIMETRIC DETERMINATION OF MANGANESE (Chemistry 51 Version) The objective of this experiment is to determine the percentage of manganese in a steel sample, using colorimetric methods of analysis. PRINCIPLES This analysis is accomplished by dissolving the steel sample, converting all of the manganese to the intensely

  1. Chronic manganese intoxication

    SciTech Connect

    Huang, C.C.; Chu, N.S.; Lu, C.S.; Wang, J.D.; Tsai, J.L.; Tzeng, J.L.; Wolters, E.C.; Calne, D.B. (Chang Gung Medical College Hospital, Taipei, Taiwan (China))

    1989-10-01

    We report six cases of chronic manganese intoxication in workers at a ferromanganese factory in Taiwan. Diagnosis was confirmed by assessing increased manganese concentrations in the blood, scalp, and pubic hair. In addition, increased manganese levels in the environmental air were established. The patients showed a bradykinetic-rigid syndrome indistinguishable from Parkinson's disease that responded to treatment with levodopa.

  2. 210Pb and 210Po, manganese and iron cycling across the O2/H2S interface of a permanently anoxic fjord: Framvaren, Norway

    USGS Publications Warehouse

    Swarzenski, Peter W.; McKee, Brent A.; Sorenson, Kai; Todd, James F.

    1999-01-01

    Vertical profiles of dissolved and particulate 201Po and 210Pb were measured across the redox transition zone at Station F1 in Framvaren Fjord, Norway. In this fjord, a sharp decrease in pH above the O2/H2S interface facilitates the aerobic dissolution of MnO2. In contrast, Fe(II) concentrations begin to increase only at the O2/H2S interface depth. Activity profiles reveal that dissolved 210Po and 210Pb are sequestered efficiently by particulates in surface waters. As polonium-210 and lead-210 activities descend down into the aerobic manganese reduction (AMR) zone, they are remobilized during the reductive dissolution of the carrier phase oxyhydroxides. Both 210Po and 210Pb are highly enriched at the O2/H2S interface where an active community of microbes, such as anoxygenic phototrophs (e.g., Chromatium, Chlorobium sp.), thrives. The coincident peaks in 210Po and 210Pb and microbial biomass suggest a strong biological influence on the behavior of these radionuclides. There is a strong covariance between the vertical distribution of Mn and Pb, indicating that their redox cycling is closely coupled and is likely microbially mediated.

  3. 210Pb and 210Po, manganese and iron cycling across the O2/H2S interface of a permanently anoxic fjord: Framvaren, Norway

    USGS Publications Warehouse

    Swarzenski, Peter W.; McKee, Brent A.; Sorensen, Kai; Todd, James F.

    1999-01-01

    Vertical profiles of dissolved and particulate 210Po and 210b were measured across the redox transition zone at Station F1 in Framvaren Fjord, Norway. In this fjord, a sharp decrease in pH above the O2/H2S interface facilitates the aerobic dissolution of MnO2. In contrast, Fe(II) concentrations begin to increase only at the O2/H2S interface depth. Activity profiles reveal that dissolved 210Po and 210Pb are sequestered efficiently by particulates in surface waters. As polonium-210 and lead-210 activities descend down into the aerobic manganese reduction (AMR) zone, they are remobilized during the reductive dissolution of the carrier phase oxyhydroxides. Both 210Po and 210Pb are highly enriched at the O2/H2S interface where an active community of microbes, such as anoxygenic phototrophs (e.g., Chromatium, Chlorobium sp.), thrives. The coincident peaks in 210Po, 210Pb and microbial biomass suggest a strong biological influence on the behavior of these radionuclides. There is a strong covariance between the vertical distribution of Mn and Pb, indicating that their redox cycling is closely coupled and is likely microbially mediated.

  4. Assessment of the permissible exposure level to manganese in workers exposed to manganese dioxide dust

    Microsoft Academic Search

    H A Roels; P Ghyselen; J P Buchet; E Ceulemans; R R Lauwerys

    1992-01-01

    The prevalence of neuropsychological and respiratory symptoms, lung ventilatory parameters, neurofunctional performances (visual reaction time, eye-hand coordination, hand steadiness, audioverbal short term memory), and several biological parameters (calcium, iron, luteinising hormone (LH), follicle stimulating hormone (FSH), and prolactin concentrations in serum, blood counts, manganese (Mn) concentration in blood and in urine) were examined in a group of workers (n =

  5. Three manganese oxide-rich marine sediments harbor similar communities of acetate-oxidizing manganese-reducing bacteria.

    PubMed

    Vandieken, Verona; Pester, Michael; Finke, Niko; Hyun, Jung-Ho; Friedrich, Michael W; Loy, Alexander; Thamdrup, Bo

    2012-11-01

    Dissimilatory manganese reduction dominates anaerobic carbon oxidation in marine sediments with high manganese oxide concentrations, but the microorganisms responsible for this process are largely unknown. In this study, the acetate-utilizing manganese-reducing microbiota in geographically well-separated, manganese oxide-rich sediments from Gullmar Fjord (Sweden), Skagerrak (Norway) and Ulleung Basin (Korea) were analyzed by 16S rRNA-stable isotope probing (SIP). Manganese reduction was the prevailing terminal electron-accepting process in anoxic incubations of surface sediments, and even the addition of acetate stimulated neither iron nor sulfate reduction. The three geographically distinct sediments harbored surprisingly similar communities of acetate-utilizing manganese-reducing bacteria: 16S rRNA of members of the genera Colwellia and Arcobacter and of novel genera within the Oceanospirillaceae and Alteromonadales were detected in heavy RNA-SIP fractions from these three sediments. Most probable number (MPN) analysis yielded up to 10(6) acetate-utilizing manganese-reducing cells cm(-3) in Gullmar Fjord sediment. A 16S rRNA gene clone library that was established from the highest MPN dilutions was dominated by sequences of Colwellia and Arcobacter species and members of the Oceanospirillaceae, supporting the obtained RNA-SIP results. In conclusion, these findings strongly suggest that (i) acetate-dependent manganese reduction in manganese oxide-rich sediments is catalyzed by members of taxa (Arcobacter, Colwellia and Oceanospirillaceae) previously not known to possess this physiological function, (ii) similar acetate-utilizing manganese reducers thrive in geographically distinct regions and (iii) the identified manganese reducers differ greatly from the extensively explored iron reducers in marine sediments. PMID:22572639

  6. Cadmium toxicity in animal cells by interference with essential metals.

    PubMed

    Martelli, A; Rousselet, E; Dycke, C; Bouron, A; Moulis, J-M

    2006-11-01

    Cadmium is found in the environment as part of several, mainly zinc-rich, ores. It has been used in many technological applications, but biological systems generally failed to safely deal with this element. In mammalian biology, cadmium exposure jeopardizes health and mechanisms of cadmium toxicity are multifarious. Mainly because bioavailable cadmium mimics other metals that are essential to diverse biological functions, cadmium follows a Trojan horse strategy to get assimilated. Metals susceptible to cadmium deceit include calcium, zinc, and iron. The wealth of data addressing cadmium toxicity in animal cells is briefly reviewed with special emphasis on disturbance of the homeostasis of calcium, zinc, and iron. A limited number of tissues and cell types are considered as main targets for cadmium toxicity. Still, the diversity of pathways affected by cadmium exposure points to a more general threat to basic cellular functions. The poor efficiency of cellular export systems for cadmium explains the long residence time of the element in mammals. Therefore, proper disposal and educated uses of this technologically appealing, but biologically malicious, element should be favored in the future. The comprehensive knowledge of cadmium biological effects is indeed a necessary step to protect human and animal populations from environmental and anthropological exposures. PMID:16814917

  7. JOURNAL DE PHYSlQUE Colloque C I, suppl6ment au no 2-3, Tome 32, Fe'vrier-Mars 1971,page C I -76 HYPERFINE FIELDS ON MANGANESE

    E-print Network

    Paris-Sud XI, Université de

    HYPERFINE FIELDS ON MANGANESE IN IRON-MANGANESE ALLOYS P. COSTA-RIBEIRO, P. RADHAKRISHNA, D. THOULOUZE alliages de y Fe-Mn ont prevu que le moment magnetique du manganese doit varier rapidement d'environ 1.UB a environ 0,s OK pour dkterrniner le champ hyperfin sur les noyaux de manganese. Le moment magnetique qu

  8. Manganese import is a key element of the OxyR response to hydrogen peroxide in Escherichia coli

    PubMed Central

    Anjem, Adil; Varghese, Shery; Imlay, James A.

    2009-01-01

    Very little manganese is imported into Escherichia coli under routine growth conditions: the import system is weakly expressed, the manganese content is low, and a manganese-dependent enzyme is not correctly metallated. Mutants that lack MntH, the importer, grow at wild-type rates, indicating that manganese plays no critical role. However, MntH supports the growth of iron-deficient cells, suggesting that manganese can substitute for iron in activating at least some metalloenzymes. MntH is also strongly induced when cells are stressed by hydrogen peroxide. This adaptation is essential, as E. coli cannot tolerate peroxide stress if mntH is deleted. Other workers have observed that manganese improves the ability of a variety of microbes to tolerate oxidative stress, and the prevailing hypothesis is that manganese does so by chemically scavenging hydrogen peroxide and/or superoxide. We found that manganese does not protect peroxide-stressed cells by scavenging peroxide. Instead, the beneficial effects of manganese correlate with its ability to metallate mononuclear enzymes. Because iron-loaded enzymes are vulnerable to the Fenton reaction, the substitution of manganese may prevent protein damage. Accordingly, during H2O2 stress, mutants that cannot import manganese and/or are unable to sequester iron suffer high rates of protein oxidation. PMID:19400769

  9. Iron and Steel Phosphate Rock

    E-print Network

    Torgersen, Christian

    Phosphate Rock Platinum Potash Pumice Quartz Crystal Rare Earths Rhenium Rubidium Salt Sand and Gravel Platinum Tellurium Bromine Indium Potash Thallium Cadmium Iodine Pumice Thorium Cement Iron Ore Quartz

  10. High Temperature Single Crystal X-Ray Diffraction: Structure of Cubic Manganese Iodine and Manganese Bromine Boracites

    NASA Astrophysics Data System (ADS)

    Crottaz, O.; Kubel, F.; Schmid, H.

    1995-11-01

    The structural parameters of optically controlled cubic manganese iodine boracite, Mn 3B 7O 13I, and manganese bromine boracite, Mn 3B 7O 13Br, have been refined on single crystals at 421 and 580 K, respectively (space group F4¯ c , Z = 8). In order to perform these measurements, a low-cost heating device, based on a soldering iron heating element, has been used. Cell parameters were found to be 12.3404(3) Å for manganese iodine boracite and 12.3100(9) Å for manganese bromine boracite. The cell parameters and the deviation from planarity of the oxygen environment around the metal ion are found to be greater in manganese boracites than in other known cubic boracites.

  11. Mineral Migration and Influence of Meal Preparation in Iron Cookware on the Iron Nutritional Status of Vegetarian Students

    Microsoft Academic Search

    Késia Diego Quintaes; Jaime Amaya-Farfan; Fernanda Mariana Tomazini; Marcelo Antonio Morgano; Niurka Maritza de Almeyda Hajisa; José Trezza Neto

    2007-01-01

    This study evaluates iron and manganese migration from iron pans and the impact of routine meal preparation on the iron status of vegetarians. Rice and tomato sauce were cooked in iron pans. Fe and Mn quantification were done by inductively coupled plasma optical emission spectrometry. Vegetarians had their meals prepared in cast-iron cookware for 12 weeks. Tomato sauce took up

  12. Manganese laser using manganese chloride as lasant

    NASA Technical Reports Server (NTRS)

    Chen, C. J.

    1974-01-01

    A manganese vapor laser utilizing manganese chloride as a lasant has been observed and investigated. Lasing is attained by means of two consecutive electrical discharges. The maximum laser output is obtained at a vapor pressure of about 3 torr, a temperature of 680 C, and a time delay between electrical discharges of 150 microsec. The maximum energy density is 1.3 microjoule per cu cm.

  13. Manganese 2 -Complexes as Auxiliaries

    E-print Network

    Lepore, Salvatore D.

    Manganese 2 -Complexes as Auxiliaries for Stereoselective Aldol Synthesis of Allenyl Carbinols manganese auxiliary was linked via an 2 -bond to alkynyl esters and ketones using a mild complexation reaction with methylcyclopentadienyl manganese tricarbonyl. This complex readily underwent aldol reactions

  14. Non-heme manganese catalase – the ‘other’ catalase

    PubMed Central

    Whittaker, James W.

    2012-01-01

    Non-heme manganese catalases are widely distributed over microbial life and represent an environmentally important alternative to heme-containing catalases in antioxidant defense. Manganese catalases contain a binuclear manganese complex as their catalytic active site rather than a heme, and cycle between Mn2(II,II) and Mn2(III,III) states during turnover. X-ray crystallography has revealed the key structural elements of the binuclear manganese active site complex that can serve as the starting point for computational studies on the protein. Four manganese catalase enzymes have been isolated and characterized, and the enzyme appears to have a broad phylogenetic distribution including both bacteria and archae. More than 100 manganese catalase genes have been annotated in genomic databases, although the assignment of many of these putative manganese catalases needs to be experimentally verified. Iron limitation, exposure to low levels of peroxide stress, thermostability and cyanide resistance may provide the biological and environmental context for the occurrence of manganese catalases. PMID:22198285

  15. BIOLOGICAL EFFECTS OF MANGANESE

    EPA Science Inventory

    The biological effects of manganese were studied in a town on the coast of Dalmatia in which a ferromanganese plant has been operating since before World War II. The study focused on the question of whether the exposure to manganese can cause a higher incidence of respiratory dis...

  16. Biomarkers of Manganese Intoxication

    PubMed Central

    Zheng, Wei; Fu, Sherleen X.; Dydak, Ulrike; Cowan, Dallas M.

    2010-01-01

    Manganese (Mn), upon absorption, is primarily sequestered in tissue and intracellular compartments. For this reason, blood Mn concentration does not always accurately reflect Mn concentration in the targeted tissue, particularly in the brain. The discrepancy between Mn concentrations in tissue or intracellular components means that blood Mn is a poor biomarker of Mn exposure or toxicity under many conditions and that other biomarkers must be established. For group comparisons of active workers, blood Mn has some utility for distinguishing exposed from unexposed subjects, although the large variability in mean values renders it insensitive for discriminating one individual from the rest of the study population. Mn exposure is known to alter iron (Fe) homeostasis. The Mn/Fe ratio (MIR) in plasma or erythrocytes reflects not only steady-state concentrations of Mn or Fe in tested individuals, but also a biological response (altered Fe homeostasis) to Mn exposure. Recent human studies support the potential value for using MIR to distinguish individuals with Mn exposure. Additionally, magnetic resonance imaging (MRI), in combination with noninvasive assessment of ?-aminobutyric acid (GABA) by magnetic resonance spectroscopy (MRS), provides convincing evidence of Mn exposure, even without clinical symptoms of Mn intoxication. For subjects with long-term, low-dose Mn exposure or for those exposed in the past but not the present, neither blood Mn nor MRI provides a confident distinction for Mn exposure or intoxication. While plasma or erythrocyte MIR is more likely a sensitive measure, the cut-off values for MIR among the general population need to be further tested and established. Considering the large accumulation of Mn in bone, developing an X-ray fluorescence spectroscopy or neutron-based spectroscopy method may create yet another novel non-invasive tool for assessing Mn exposure and toxicity. PMID:20946915

  17. Zinc dependence of zinT (yodA) mutants and binding of zinc, cadmium and mercury by ZinT

    SciTech Connect

    Kershaw, Christopher J.; Brown, Nigel L. [School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Hobman, Jon L. [School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)], E-mail: jon.hobman@nottingham.ac.uk

    2007-12-07

    ZinT (B1973), previously known as YodA, was originally characterised as a cadmium-induced periplasmic protein under the regulation of Fur and SoxS. Here we describe a decrease in zinT transcript in response to elevated copper concentrations and the zinc and copper dependent phenotype of a {delta}zinT strain. Cadmium sensitivity of the {delta}zinT strain was not observed. We demonstrate the binding of nickel, zinc, cadmium, and mercury, but not cobalt, copper, iron, and manganese, to purified ZinT using mass spectrometry. This and previous studies support the hypothesis that ZinT plays a role in zinc homeostasis and is required for growth under zinc limited conditions, suggesting that ZinT is either a periplasmic zinc chaperone or is involved in zinc import. Limited metal ion discrimination results in regulation of PzinT in a non-specific manner, which is mirrored in the binding of several different heavy metals by ZinT.

  18. Release of aluminum, arsenic, cadmium, chromium, copper, iron, lead, and zinc in a coal leachate, and their removal from solution undergoing neutralization

    Microsoft Academic Search

    Tatum

    1992-01-01

    Whole coal contains significant amounts of iron pyrite which is oxidized ultimately to ferric acid sulfate. As a result, trace elements are released from the coal and other minerals in potentially hazardous concentrations. The purpose of this research was to: (1) study the release and mobility of selected trace elements during the weathering of coal; (2) seek to understand factors

  19. A manganese-rich environment supports superoxide dismutase activity in a Lyme disease pathogen, Borrelia burgdorferi.

    PubMed

    Aguirre, J Dafhne; Clark, Hillary M; McIlvin, Matthew; Vazquez, Christine; Palmere, Shaina L; Grab, Dennis J; Seshu, J; Hart, P John; Saito, Mak; Culotta, Valeria C

    2013-03-22

    The Lyme disease pathogen Borrelia burgdorferi represents a novel organism in which to study metalloprotein biology in that this spirochete has uniquely evolved with no requirement for iron. Not only is iron low, but we show here that B. burgdorferi has the capacity to accumulate remarkably high levels of manganese. This high manganese is necessary to activate the SodA superoxide dismutase (SOD) essential for virulence. Using a metalloproteomic approach, we demonstrate that a bulk of B. burgdorferi SodA directly associates with manganese, and a smaller pool of inactive enzyme accumulates as apoprotein. Other metalloproteins may have similarly adapted to using manganese as co-factor, including the BB0366 aminopeptidase. Whereas B. burgdorferi SodA has evolved in a manganese-rich, iron-poor environment, the opposite is true for Mn-SODs of organisms such as Escherichia coli and bakers' yeast. These Mn-SODs still capture manganese in an iron-rich cell, and we tested whether the same is true for Borrelia SodA. When expressed in the iron-rich mitochondria of Saccharomyces cerevisiae, B. burgdorferi SodA was inactive. Activity was only possible when cells accumulated extremely high levels of manganese that exceeded cellular iron. Moreover, there was no evidence for iron inactivation of the SOD. B. burgdorferi SodA shows strong overall homology with other members of the Mn-SOD family, but computer-assisted modeling revealed some unusual features of the hydrogen bonding network near the enzyme's active site. The unique properties of B. burgdorferi SodA may represent adaptation to expression in the manganese-rich and iron-poor environment of the spirochete. PMID:23376276

  20. Cadmium inhalation and male reproductive toxicity

    SciTech Connect

    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.

  1. Effects of methionine chelate- or yeast proteinate-based supplement of copper, iron, manganese and zinc on broiler growth performance, their distribution in the tibia and excretion into the environment.

    PubMed

    Singh, Abhay Kumar; Ghosh, Tapan Kumar; Haldar, Sudipto

    2015-04-01

    A straight-run flock of 1-day-old Cobb 400 chicks (n?=?432) was distributed into four treatment groups (9 replicate pens in each group, 12 birds in a pen) for a 38-day feeding trial evaluating the effects of a methionine chelate (Met-TM)- or a yeast proteinate (Yeast-TM)-based supplement of copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) on growth performance, bone criteria and some metabolic indices in commercial broiler chickens. The diets were either not supplemented with any trace elements at all (negative control, NC) or supplemented with an inorganic (sulphate) trace element premix (inorganic TM (ITM), 1 g/kg feed), the Met-TM (1 g/kg feed) and the Yeast-TM (0.5 g/kg feed). Body weight, feed conversion ratio and dressed meat yield at 38 days were better in the Yeast-TM-supplemented group as compared with the NC, ITM and Met-TM groups (p?

  2. Globally sustainable manganese metal production and use.

    PubMed

    Hagelstein, Karen

    2009-09-01

    The "cradle to grave" concept of managing chemicals and wastes has been a descriptive analogy of proper environmental stewardship since the 1970s. The concept incorporates environmentally sustainable product choices-such as metal alloys utilized steel products which civilization is dependent upon. Manganese consumption is related to the increasing production of raw steel and upgrading ferroalloys. Nonferrous applications of manganese include production of dry-cell batteries, plant fertilizer components, animal feed and colorant for bricks. The manganese ore (high grade 35% manganese) production world wide is about 6 million ton/year and electrolytic manganese metal demand is about 0.7 million ton/year. The total manganese demand is consumed globally by industries including construction (23%), machinery (14%), and transportation (11%). Manganese is recycled within scrap of iron and steel, a small amount is recycled within aluminum used beverage cans. Recycling rate is 37% and efficiency is estimated as 53% [Roskill Metals and Minerals Reports, January 13, 2005. Manganese Report: rapid rise in output caused by Chinese crude steel production. Available from: http://www.roskill.com/reports/manganese.]. Environmentally sustainable management choices include identifying raw material chemistry, utilizing clean production processes, minimizing waste generation, recycling materials, controlling occupational exposures, and collecting representative environmental data. This paper will discuss two electrolytically produced manganese metals, the metal production differences, and environmental impacts cited to date. The two electrolytic manganese processes differ due to the addition of sulfur dioxide or selenium dioxide. Adverse environmental impacts due to use of selenium dioxide methodology include increased water consumption and order of magnitude greater solid waste generation per ton of metal processed. The use of high grade manganese ores in the electrolytic process also reduces the quantity of solid wastes generated during processing. Secondary aluminum facilities have reported hazardous waste generation management issues due to baghouse dusts from rotary furnaces processing selenium contaminated manganese alloys. Environmental impacts resulting from industry are represented by emission inventories of chemical releases to the air, water, and soil. The U.S. metals industry releases reported to EPA Toxic Release Inventory indicate the primary metals industry is the major source of metal air toxic emissions, exceeding electric utility air toxic emissions. The nonferrous metals industry is reported to be the Organization for Economic Co-operation and Development (OECD) most intensive airborne and land pollution source of bioaccumulative metals. However, total waste emissions from industries in the OECD countries have declined due to improving energy consumption. Emission registers and access are improving around the world. However, environmental databases for metal particulates have low confidence ratings since the majority of air toxic emissions are not reported, not monitored, or are estimated based on worst-case emission factors. Environmental assessments including biological monitoring are necessary to validate mandated particulate metal emission reductions and control technologies during metal processing. PMID:19467569

  3. Cellular Iron Distribution in Bacillus anthracis

    PubMed Central

    Tu, Wang Yung; Pohl, Susanne; Gray, Joe; Robinson, Nigel J.; Harwood, Colin R.

    2012-01-01

    Although successful iron acquisition by pathogens within a host is a prerequisite for the establishment of infection, surprisingly little is known about the intracellular distribution of iron within bacterial pathogens. We have used a combination of anaerobic native liquid chromatography, inductively coupled plasma mass spectrometry, principal-component analysis, and peptide mass fingerprinting to investigate the cytosolic iron distribution in the pathogen Bacillus anthracis. Our studies identified three of the major iron pools as being associated with the electron transfer protein ferredoxin, the miniferritin Dps2, and the superoxide dismutase (SOD) enzymes SodA1 and SodA2. Although both SOD isozymes were predicted to utilize manganese cofactors, quantification of the metal ions associated with SodA1 and SodA2 in cell extracts established that SodA1 is associated with both manganese and iron, whereas SodA2 is bound exclusively to iron in vivo. These data were confirmed by in vitro assays using recombinant protein preparations, showing that SodA2 is active with an iron cofactor, while SodA1 is cambialistic, i.e., active with manganese or iron. Furthermore, we observe that B. anthracis cells exposed to superoxide stress increase their total iron content more than 2-fold over 60 min, while the manganese and zinc contents are unaffected. Notably, the acquired iron is not localized to the three identified cytosolic iron pools. PMID:22178968

  4. Hot coal gas desulfurization with manganese-based sorbents

    SciTech Connect

    Hepworth, M.T.; Ben-Slimane, R.

    1994-12-01

    The focus of work being performed on Hot Coal Gas Desulfurization at the Morgantown Energy Technology Center is primarily in the use of zinc ferrite and zinc titanate sorbents; however, prior studies indicated that an alternate sorbent, manganese dioxide-containing ore in mixture with alumina (75 wt % ore + 25 wt % Al{sub 2}O{sub 3}) may be a viable alternative to zinc-based sorbents. Manganese, for example, has a lower vapor pressure in the elemental state than zinc hence it is not as likely to undergo depletion from the sorbent surface upon loading and regeneration cycles. Also manganese oxide is less readily reduced to the elemental state than iron hence the range of reduction potentials for oxygen is somewhat greater than for zinc ferrite. In addition, thermodynamic analysis of the manganese-oxygen-sulfur system shows it to be less amenable to sulfation than zinc ferrite. Potential also exists for utilization of manganese at higher temperatures than zinc ferrite or zinc titanate. This annual topical report documents progress in pelletizing and testing via thermo-gravimetric analysis of individual pellet formulations of manganese ore/alumina combinations and also manganese carbonate/alumina with two binders, dextrin and bentonite.

  5. HIDROGEOLOGICAL MODEL OF THE ITABIRA IRON ORE DISTRICT

    Microsoft Academic Search

    Agostinho Fernandez; Sobreiro Neto

    2001-01-01

    The Itabira Iron Ore District is located in the region called Quadrilátero Ferrífero (Iron Quadrangle), a very rich region with plenty of mineral resources (iron, gold, manganese, bauxite etc.). During the last 50 years, CVRD (Companhia Vale do Rio Doce) has exploited about one billion tons of iron ore in Itabira. In 1985, CVRD started dewatering activities of those mines

  6. Vertical Advection Diffusion and Redox Potentials as Controls on the Distribution of Manganese and Other Trace Metals Dissolved in Waters of the Black Sea

    Microsoft Academic Search

    Derek W. Spencer; Peter G. Brewer

    1971-01-01

    Profiles of dissolved manganese, copper, iron, and zinc show that the distributions of these elements are markedly affected by redox reactions at the boundary between oxygenated surface waters and the sulfide-containing deep waters. Copper and zinc are depleted in the deep water by precipitation as insoluble sulfides. The concentrations of manganese and iron in the deep water greatly exceed those

  7. High manganese concentrations in rocks at Gale crater, Mars

    NASA Astrophysics Data System (ADS)

    Lanza, Nina L.; Fischer, Woodward W.; Wiens, Roger C.; Grotzinger, John; Ollila, Ann M.; Cousin, Agnes; Anderson, Ryan B.; Clark, Benton C.; Gellert, Ralf; Mangold, Nicolas; Maurice, Sylvestre; Le Mouélic, Stéphane; Nachon, Marion; Schmidt, Mariek; Berger, Jeffrey; Clegg, Samuel M.; Forni, Olivier; Hardgrove, Craig; Melikechi, Noureddine; Newsom, Horton E.; Sautter, Violaine

    2014-08-01

    The surface of Mars has long been considered a relatively oxidizing environment, an idea supported by the abundance of ferric iron phases observed there. However, compared to iron, manganese is sensitive only to high redox potential oxidants, and when concentrated in rocks, it provides a more specific redox indicator of aqueous environments. Observations from the ChemCam instrument on the Curiosity rover indicate abundances of manganese in and on some rock targets that are 1-2 orders of magnitude higher than previously observed on Mars, suggesting the presence of an as-yet unidentified manganese-rich phase. These results show that the Martian surface has at some point in time hosted much more highly oxidizing conditions than has previously been recognized.

  8. Corrosion of stainless steel piping in high manganese fresh water

    SciTech Connect

    Avery, R.E. [Nickel Development Inst., Londonderry, NH (United States); Lutey, R.W. [Buckman Labs., Memphis, TN (United States); Musick, J. [Whitman and Howard, Portland, ME (United States); Pinnow, K.E. [Crucible Research, Pittsburgh, PA (United States); Tuthill, A.H. [Nickel Development Inst., Blacksburg, VA (United States)

    1996-09-01

    A potable water treatment plant, designed to reduce manganese and iron in well water, experienced leaks in the 16 in. (406 mm) raw water headers about nine months after startup. The material, type 304 (UNS 30403) stainless steel, was purchased to American Society of Testing Materials specification A 778, with additional stipulations governing internal finish, the use of filler metal, and pickling for scale removal. Laboratory screenings of deposits for bacteria revealed some potentially additive corrosive effects from microbial action. However, the correlation of corrosion with the presence or absence of heat tint in the heat-affected zone of the circumferential welds prevailed as a primary cause of the corrosion observed beneath an adherent manganese-iron deposit in a low chloride, high manganese, raw water.

  9. The effects of chemical remediation treatments on the extractability and speciation of cadmium and lead in contaminated soils.

    PubMed

    Chen, Z S; Lee, G J; Liu, J C

    2000-07-01

    Two rural soils contaminated by cadmium (Cd) and lead (Pb) were used to evaluate the effect of different chemical treatments on changes in speciation and extractability of Cd and Pb, and in phytoavailability to wheat. Triplicates of seven chemical treatments were tested to compare and evaluate the remediation techniques for contaminated soils using pot experiments. Treatments applied were calcium carbonate, a high quantity of phosphate salt, hog composts, iron oxide, manganese oxide, zeolite, and unamended control. Wheat (Triticum aestivum) was planted in the different amended soils for a further one month to evaluate the effectiveness of treatments on uptake of Cd and Pb by the wheat shoots. Results indicated that addition of calcium carbonate, manganese oxide, or zeolite reduces the extractability of Cd or Pb in both soils, and significantly reduce the uptake of Cd and Pb by wheat shoots. Changes in the extractability and metal sequential fractionations indicate that the exchangeable (or available) form of Cd and Pb in two soils can be transformed into unavailable forms after these amendments. PMID:10819206

  10. Drinking Water Problems: Iron and Manganese (Spanish)

    E-print Network

    Dozier, Monty; McFarland, Mark L.

    2004-02-20

    manganeso se acumulan en los tubos de ca?er?as, tanques de presi?n, calen- tadores de agua y equipo ablandador de agua. Estos dep?sitos restringen el flujo del agua y reducen la presi?n del agua. M?s energ?a se requiere para bombear agua a trav?s de tubos...?culas suministro de agua part?culas rojizas - caf?s que se asientan cuando el agua se estanca Corrosi?n de tuber?a y El agua del grifo contiene part?culas Eleve el pH del agua y use un filtro equipo rojizas-caf?s que se asientan de part?culas cuando el agua se...

  11. Oscillator strengths for ionized iron and manganese

    NASA Technical Reports Server (NTRS)

    De Boer, K. S.; Pottasch, S. R.; Morton, D. C.; York, D. G.

    1974-01-01

    The observed strengths of interstellar absorption lines of Fe II and Mn II in the spectra of alpha Vir, beta Cen, pi Sco, and zeta Oph along with laboratory f values of some of these lines between 2343 and 2606 A have been used to determine curves of growth for these ions and the f-values of ten lines of Fe II and three lines of Mn II between 1055 and 1261 A. The Fe and Mn abundances are derived.

  12. Biologically relevant heterodinuclear iron-manganese complexes.

    PubMed

    Carboni, Michaël; Clémancey, Martin; Molton, Florian; Pécaut, Jacques; Lebrun, Colette; Dubois, Lionel; Blondin, Geneviève; Latour, J-M

    2012-10-01

    The heterodinuclear complexes [Fe(III)Mn(II)(L-Bn)(?-OAc)(2)](ClO(4))(2) (1) and [Fe(II)Mn(II)(L-Bn)(?-OAc)(2)](ClO(4)) (2) with the unsymmetrical dinucleating ligand HL-Bn {[2-bis[(2-pyridylmethyl)aminomethyl

  13. Manganese in dwarf spheroidal galaxies

    E-print Network

    North, P; Jablonka, P; Hill, V; Shetrone, M; Letarte, B; Lemasle, B; Venn, K A; Battaglia, G; Tolstoy, E; Irwin, M J; Primas, F; Francois, P

    2012-01-01

    We provide manganese abundances (corrected for the effect of the hyperfine structure) for a large number of stars in the dwarf spheroidal galaxies Sculptor and Fornax, and for a smaller number in the Carina and Sextans dSph galaxies. Abundances had already been determined for a number of other elements in these galaxies, including alpha and iron-peak ones, which allowed us to build [Mn/Fe] and [Mn/alpha] versus [Fe/H] diagrams. The Mn abundances imply sub-solar [Mn/Fe] ratios for the stars in all four galaxies examined. In Sculptor, [Mn/Fe] stays roughly constant between [Fe/H]\\sim -1.8 and -1.4 and decreases at higher iron abundance. In Fornax, [Mn/Fe] does not vary in any significant way with [Fe/H]. The relation between [Mn/alpha] and [Fe/H] for the dSph galaxies is clearly systematically offset from that for the Milky Way, which reflects the different star formation histories of the respective galaxies. The [Mn/alpha] behavior can be interpreted as a result of the metal-dependent Mn yields of type II and ...

  14. Process for producing cadmium sulfide on a cadmium telluride surface

    DOEpatents

    Levi, Dean H. (Lakewood, CO); Nelson, Art J. (Longmont, CO); Ahrenkiel, Richard K. (Lakewood, CO)

    1996-01-01

    A process for producing a layer of cadmium sulfide on a cadmium telluride surface to be employed in a photovoltaic device. The process comprises providing a cadmium telluride surface which is exposed to a hydrogen sulfide plasma at an exposure flow rate, an exposure time and an exposure temperature sufficient to permit reaction between the hydrogen sulfide and cadmium telluride to thereby form a cadmium sulfide layer on the cadmium telluride surface and accomplish passivation. In addition to passivation, a heterojunction at the interface of the cadmium sulfide and the cadmium telluride can be formed when the layer of cadmium sulfide formed on the cadmium telluride is of sufficient thickness.

  15. [Anemia induced by cadmium intoxication].

    PubMed

    Horiguchi, Hyogo

    2007-05-01

    Anemia is commonly induced by chronic cadmium (Cd) intoxication. Three main factors are involved in the development of Cd-induced anemia: hemolytic, iron-deficiency, and renal. Intravascular hemolysis can occur at the early stage of Cd exposure owing to the direct damaging effect on erythrocytes. In addition, Cd that accumulates in erythrocytes affects membrane cytoskeletons and decreases cell deformability, and these cells are then trapped and destroyed in the spleen. Iron deficiency can be detected in animals after an oral exposure to Cd, which competes with iron for absorption in the intestines, leading to anemia. However, an increase in body iron content along with anemia is often observed in cases of parenteral exposure or itai-itai disease. Therefore, it is estimated that Cd disrupts the efficient usage of iron in hemoglobin synthesis in the body. Renal anemia is observed during the very last phase of chronic, severe Cd intoxication, such as itai-itai disease, showing a decrease in the production of erythropoietin from renal tubular cells. Because the renal anemia is based on the same pathophysiology as Cd-induced osteomalacia, which is derived from the disturbance of mineral metabolism due to renal tubular dysfunction, it is reasonable to include renal anemia in the criteria for the diagnosis of itai-itai disease. Hemodilution could also contribute to the development of Cd-induced anemia. Bone marrow hypoplasia or the inhibition of heme synthesis might only be involved in Cd-induced anemia in severe cases of Cd intoxication. PMID:17575787

  16. Occupational exposure to manganese.

    PubMed Central

    Sari?, M; Marki?evi?, A; Hrusti?, O

    1977-01-01

    The relationship between the degree of exposure and biological effects of manganese was studied in a group of 369 workers employed in the production of ferroalloys. Two other groups of workers, from an electrode plant and from an aluminium rolling mill, served as controls. Mean manganese concentrations at work places where ferroalloys were produced varied from 0-301 to 20-442 mg/m3. The exposure level of the two control groups was from 2 to 30 microgram/m3 and from 0-05 to 0-07 microgram/m3, in the electrode plant and rolling mill respectively. Sixty-two (16-8%) manganese alloy workers showed some signs of neurological impairment. These signs were noticeably less in the two control groups (5-8% and 0%) than in the occupationally exposed group. Subjective symptoms, which are nonspecific but may be symptoms of subclinical manganism, were not markedly different in the three groups. However, in the manganese alloy workers some of the subjective symptoms occurred more frequently in heavier smokers than in light smokers or nonsmokers. Heavier smokers engaged in manganese alloy production showed some of the subjective symptoms more often than heavier smokers from the control groups. PMID:871441

  17. Chelation of cadmium by combining deferasirox and deferiprone in rats.

    PubMed

    Jamilaldin Fatemi, S; Saljooghi, Amir Shokooh; Balooch, Faezeh Dahooee; Iranmanesh, Marzieh; Golbafan, Mohammad Reza

    2011-05-01

    The present research aimed to characterize the potential efficiency of two chelators after cadmium administration for 60 days following two dose levels of 20 and 40 mg/kg body weight daily to male rats. However, the hypothesis that the two chelators might be more efficient as combined therapy than as single therapy in removing cadmium from the body was considered. In this way, two known chelators deferasirox and deferiprone (L(1)) were chosen and tested in the acute rat model. Two chelators were given orally as a single or combined therapy for the period of a week. Cadmium and iron concentrations in various tissues were determined by graphite furnace and flame atomic absorption spectrometry methods, respectively. The combined chelation therapy results show that Deferasirox and L(1) are able to remove cadmium ions from the body while iron concentration returned to the normal level and symptoms are also decreased. PMID:21245204

  18. Manganese ferrite nanoparticle micellar nanocomposites as MRI contrast agent for liver imaging

    Microsoft Academic Search

    Jian Lu; Shuli Ma; Jiayu Sun; Chunchao Xia; Chen Liu; Zhiyong Wang; Xuna Zhao; Fabao Gao; Qiyong Gong; Bin Song; Xintao Shuai; Hua Ai; Zhongwei Gu

    2009-01-01

    Iron oxide nanoparticles are effective contrast agents for enhancement of magnetic resonance imaging at tissue, cellular or even molecular levels. In this study, manganese doped superparamagnetic iron oxide (Mn-SPIO) nanoparticles were used to form ultrasensitive MRI contrast agents for liver imaging. Hydrophobic Mn-SPIO nanoparticles are synthesized in organic phase and then transferred into water with the help of block copolymer

  19. Recent developments in manganese speciation

    Microsoft Academic Search

    Gareth F. Pearson; Gillian M. Greenway

    2005-01-01

    Manganese is an abundant element in the environment and widely used throughout industry. Although manganese has relatively low toxicity, in chronic overdose or prolonged occupational exposure, it can cause severe disruption to the central nervous system. This article illustrates the requirements for manganese speciation and reviews the analytical methods applied to such studies, including electroanalytical techniques and hybrid systems, such

  20. The ubiquity of iron.

    PubMed

    Frey, Perry A; Reed, George H

    2012-09-21

    The importance of iron in living systems can be traced to the many complexes within which it is found, to its chemical mobility in undergoing oxidation-reduction reactions, and to the abundance of iron in Earth's crust. Iron is the most abundant element, by mass, in the Earth, constituting about 80% of the inner and outer cores of Earth. The molten outer core is about 8000 km in diameter, and the solid inner core is about 2400 km in diameter. Iron is the fourth most abundant element in Earth's crust. It is the chemically functional component of mononuclear iron complexes, dinuclear iron complexes, [2Fe-2S] and [4Fe-4S] clusters, [Fe-Ni-S] clusters, iron protophorphyrin IX, and many other complexes in protein biochemistry. Metals such as nickel, cobalt, copper, and manganese are present in the crust and could in principle function chemically in place of iron, but they are scarce in Earth's crust. Iron is plentiful because of its nuclear stability in stellar nuclear fusion reactions. It seems likely that other solid planets, formed by the same processes as Earth, would also foster the evolution of life and that iron would be similarly important to life on those planets as it is on Earth. PMID:22845493

  1. Manganese abundances in Galactic bulge red giants

    E-print Network

    Barbuy, B; Zoccali, M; Minniti, D; Renzini, A; Ortolani, S; Gomez, A; Trevisan, M; Dutra, N

    2013-01-01

    Manganese is mainly produced in type II SNe during explosive silicon burning, in incomplete Si-burning regions, and depends on several nucleosynthesis environment conditions, such as mass cut beween the matter ejected and falling back onto the remnant, electron and neutron excesses, mixing fallback, and explosion energy. Manganese is also produced in type Ia SNe. The aim of this work is the study of abundances of the iron-peak element Mn in 56 bulge giants, among which 13 are red clump stars. Four bulge fields along the minor axis are inspected. The study of abundances of Mn-over-Fe as a function of metallicity in the Galactic bulge may shed light on its production mechanisms. High-resolution spectra were obtained using the FLAMES+UVES spectrograph on the Very Large Telescope. The spectra were obtained within a program to observe 800 stars using the GIRAFFE spectrograph, together with the present UVES spectra. We aim at identifying the chemical evolution of manganese, as a function of metallicity, in the Gala...

  2. ARSENIC REMOVAL BY IRON REMOVAL PROCESSES

    EPA Science Inventory

    Presentation will discuss the removal of arsenic from drinking water using iron removal processes that include oxidation/filtration and the manganese greensand processes. Presentation includes results of U.S. EPA field studies conducted in Michigan and Ohio on existing iron remo...

  3. Manganese, Metallogenium, and Martian Microfossils

    NASA Technical Reports Server (NTRS)

    Stein, L. Y.; Nealson, K. H.

    1999-01-01

    Manganese could easily be considered an abundant element in the Martian regolith, assuming that the composition of martian meteorites reflects the composition of the planet. Mineralogical analyses of 5 SNC meteorites have revealed an average manganese oxide concentration of 0.48%, relative to the 0.1% concentration of manganese found in the Earth's crust. On the Earth, the accumulation of manganese oxides in oceans, soils, rocks, sedimentary ores, fresh water systems, and hydrothermal vents can be largely attributed to microbial activity. Manganese is also a required trace nutrient for most life forms and participates in many critical enzymatic reactions such as photosynthesis. The wide-spread process of bacterial manganese cycling on Earth suggests that manganese is an important element to both geology and biology. Furthermore, there is evidence that bacteria can be fossilized within manganese ores, implying that manganese beds may be good repositories for preserved biomarkers. A particular genus of bacteria, known historically as Metallogenium, can form star-shaped manganese oxide minerals (called metallogenium) through the action of manganese oxide precipitation along its surface. Fossilized structures that resemble metallogenium have been found in Precambrian sedimentary formations and in Cretaceous-Paleogene cherts. The Cretaceous-Paleogene formations are highly enriched in manganese and have concentrations of trace elements (Fe, Zn, Cu, and Co) similar to modern-day manganese oxide deposits in marine environments. The appearance of metallogenium-like fossils associated with manganese deposits suggests that bacteria may be preserved within the minerals that they form. Additional information is contained in the original extended abstract.

  4. Managing the manganese: molecular mechanisms of manganese transport and homeostasis.

    PubMed

    Pittman, Jon K

    2005-09-01

    Manganese (Mn) is an essential metal nutrient for plants. Recently, some of the genes responsible for transition metal transport in plants have been identified; however, only relatively recently have Mn2+ transport pathways begun to be identified at the molecular level. These include transporters responsible for Mn accumulation into the cell and release from various organelles, and for active sequestration into endomembrane compartments, particularly the vacuole and the endoplasmic reticulum. Several transporter gene families have been implicated in Mn2+ transport, including cation/H+ antiporters, natural resistance-associated macrophage protein (Nramp) transporters, zinc-regulated transporter/iron-regulated transporter (ZRT/IRT1)-related protein (ZIP) transporters, the cation diffusion facilitator (CDF) transporter family, and P-type ATPases. The identification of mutants with altered Mn phenotypes can allow the identification of novel components in Mn homeostasis. In addition, the characterization of Mn hyperaccumulator plants can increase our understanding of how plants can adapt to excess Mn, and ultimately allow the identification of genes that confer this stress tolerance. The identification of genes responsible for Mn2+ transport has substantially improved our understanding of plant Mn homeostasis. PMID:16101910

  5. Separate pathways for cellular uptake of ferric and ferrous iron.

    PubMed

    Conrad, M E; Umbreit, J N; Moore, E G; Hainsworth, L N; Porubcin, M; Simovich, M J; Nakada, M T; Dolan, K; Garrick, M D

    2000-10-01

    Separate pathways for transport of nontransferrin ferric and ferrous iron into tissue cultured cells were demonstrated. Neither the ferric nor ferrous pathway was shared with either zinc or copper. Manganese shared the ferrous pathway but had no effect on cellular uptake of ferric iron. We postulate that ferric iron was transported into cells via beta(3)-integrin and mobilferrin (IMP), whereas ferrous iron uptake was facilitated by divalent metal transporter-1 (DMT-1; Nramp-2). These conclusions were documented by competitive inhibition studies, utilization of a beta(3)-integrin antibody that blocked uptake of ferric but not ferrous iron, development of an anti-DMT-1 antibody that blocked ferrous iron and manganese uptake but not ferric iron, transfection of DMT-1 DNA into tissue culture cells that showed enhanced uptake of ferrous iron and manganese but neither ferric iron nor zinc, hepatic metal concentrations in mk mice showing decreased iron and manganese but not zinc or copper, and data showing that the addition of reducing agents to tissue culture media altered iron binding to proteins of the IMP and DMT-1 pathways. Although these experiments show ferric and ferrous iron can enter cells via different pathways, they do not indicate which pathway is dominant in humans. PMID:11005764

  6. Determination of Cadmium, Chromium, Copper, Iron, Lead, Magnesium, Manganese, Potassium and Zinc in Mint Tea Leaves by Electrothermal Atomizer Atomic Absorption Spectrometry in Samples Purchased at Local Supermarkets and Marketplaces

    Microsoft Academic Search

    Ante Prki?; Josipa Giljanovi?; Sandra Petri?evi?; Mia Brklja?a; Marija Brali?

    2012-01-01

    The concentrations of Cd, Cr, Cu, Fe, K, Mg, Mn, Pb and Zn in 14 different samples of mint leaves (Mentha piperitae folium) and tea bags purchased in local supermarkets and marketplaces in Split, Croatia were determined. Electrothermal atomic absorption spectrometry (ETAAS) was applied in this work. Mint tea samples purchased at marketplaces contained: Cd (0.021–0.357 mg kg), Cr (<0.01–52.3 mg kg),

  7. Us food and drug administration survey of cadmium, lead and other elements in clams and oysters

    Microsoft Academic Search

    Stephen G. Capar; Norma J. Yess

    1996-01-01

    In Fiscal Years 1985\\/1986, the US Food and Drug Administration conducted a survey of cadmium, lead and other elements in fresh clams and oysters collected from US coastal areas in use for shellfish production. Shellfish were analysed for cadmium and lead by using a dry ash?anodic stripping voltammetric method. Other elements (aluminium, arsenic, beryllium, calcium, chromium, cobalt, copper, iron, magnesium,

  8. CADMIUM SOLUBILITY IN PADDY SOILS: EFFECTS OF SOIL OXIDATION, METAL SULFIDES AND COMPETITIVE IONS.

    EPA Science Inventory

    Cadmium (Cd) is a non-essential element for human nutrition and is an agricultural soil contaminant. Cadmium solubility in paddy soils affects Cd accumulation in the grain of rice. This is a human health risk, exacerbated by the fact that rice grains are deficient in iron (Fe) an...

  9. Cadmium and renal cancer

    SciTech Connect

    Il'yasova, Dora [Department of Cancer Biology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157 (United States); Department of Public Health Sciences, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157 (United States); Schwartz, Gary G. [Department of Cancer Biology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157 (United States) and Department of Public Health Sciences, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157 (United States)]. E-mail: gschwart@wfubmc.edu

    2005-09-01

    Background: Rates of renal cancer have increased steadily during the past two decades, and these increases are not explicable solely by advances in imaging modalities. Cadmium, a widespread environmental pollutant, is a carcinogen that accumulates in the kidney cortex and is a cause of end-stage renal disease. Several observations suggest that cadmium may be a cause of renal cancer. Methods: We performed a systematic review of the literature on cadmium and renal cancer using MEDLINE for the years 1966-2003. We reviewed seven epidemiological and eleven clinical studies. Results: Despite different methodologies, three large epidemiologic studies indicate that occupational exposure to cadmium is associated with increased risk renal cancer, with odds ratios varying from 1.2 to 5.0. Six of seven studies that compared the cadmium content of kidneys from patients with kidney cancer to that of patients without kidney cancer found lower concentrations of cadmium in renal cancer tissues. Conclusions: Exposure to cadmium appears to be associated with renal cancer, although this conclusion is tempered by the inability of studies to assess cumulative cadmium exposure from all sources including smoking and diet. The paradoxical findings of lower cadmium content in kidney tissues from patients with renal cancer may be caused by dilution of cadmium in rapidly dividing cells. This and other methodological problems limit the interpretation of studies of cadmium in clinical samples. Whether cadmium is a cause of renal cancer may be answered more definitively by future studies that employ biomarkers of cadmium exposure, such as cadmium levels in blood and urine.

  10. Effects of cadmium on nutrient uptake and translocation by Indian Mustard.

    PubMed

    Jiang, X J; Luo, Y M; Liu, Q; Liu, S L; Zhao, Q G

    2004-01-01

    Plants that hyperaccumulate metals are ideal subjects for studying the mechanisms of metal and mineral nutrient uptake in the plant kingdom. Indian Mustard (Brassica juncea) has been shown to accumulate moderate levels of Cd, Pb, Cr, Ni, Zn, and Cu. In this experiment, 10 levels of Cd concentration treatments were imposed by adding 10-190 mg Cd kg(-1) to the soils as cadmium nitrate [Cd(NO3)2]. The effect of Cd on phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and the micronutrients iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in B. juncea was studied. Plant growth was affected negatively by Cd, root biomass decreased significantly at 170 mg Cd kg(-1) dry weight soils treatment. Cadmium accumulation both in shoots and roots increased with increasing soil Cd treatments. The highest concentration of Cd was up to 300 mg kg(-1) d.w. in the roots and 160 mg kg(-1) d.w. in the shoots. The nutrients mainly affected by Cd were P, K, Ca, Fe, and Zn in the roots, and P, K, Ca, and Cu in the shoots. K and P concentrations in roots increased significantly when Cd was added at 170 mg kg(-1), and this was almost the same level at which root growth was inhibited. Zn concentrations in roots decreased significantly when added Cd concentration was increased from 50 to 110 mg kg(-1), then remained constant with Cd treatments from 110 to 190 mg kg(-1). However, Zn concentrations in the shoots seemed less affected by Cd. It is possible that Zn uptake was affected by the Cd but not the translocation of Zn within the plant. Ca and Mg accumulation in roots and shoots showed similar trends. This result indicates that Ca and Mg uptake is a non-specific process. PMID:15499789

  11. Manganese in dwarf spheroidal galaxies

    NASA Astrophysics Data System (ADS)

    North, P.; Cescutti, G.; Jablonka, P.; Hill, V.; Shetrone, M.; Letarte, B.; Lemasle, B.; Venn, K. A.; Battaglia, G.; Tolstoy, E.; Irwin, M. J.; Primas, F.; François, P.

    2012-05-01

    We provide manganese abundances (corrected for the effect of the hyperfine structure) for a large number of stars in the dwarf spheroidal galaxies Sculptor and Fornax, and for a smaller number in the Carina and Sextans dSph galaxies. Abundances had already been determined for a number of other elements in these galaxies, including ? and iron-peak ones, which allowed us to build [Mn/Fe] and [Mn/?] versus [Fe/H] diagrams. The Mn abundances imply sub-solar [Mn/Fe] ratios for the stars in all four galaxies examined. In Sculptor, [Mn/Fe] stays roughly constant between [Fe/H] ~ -1.8 and -1.4 and decreases at higher iron abundance. In Fornax, [Mn/Fe] does not vary in any significant way with [Fe/H]. The relation between [Mn/?] and [Fe/H] for the dSph galaxies is clearly systematically offset from that for the Milky Way, which reflects the different star formation histories of the respective galaxies. The [Mn/?] behavior can be interpreted as a result of the metal-dependent Mn yields of Type II and Type Ia supernovae. We also computed chemical evolution models for star formation histories matching those determined empirically for Sculptor, Fornax, and Carina, and for the Mn yields of SNe Ia, which were assumed to be either constant or variable with metallicity. The observed [Mn/Fe] versus [Fe/H] relation in Sculptor, Fornax, and Carina can be reproduced only by the chemical evolution models that include a metallicity-dependent Mn yield from the SNe Ia. Based on observations made with the FLAMES-GIRAFFE multi-object spectrograph mounted on the Kuyen VLT telescope at ESO-Paranal Observatory (programs 171.B-0588, 074.B-0415 and 076.B-0146).Appendices are available in electronic form at http://www.aanda.org

  12. Biological manganese removal from acid mine drainage in constructed wetlands and prototype bioreactors.

    PubMed

    Hallberg, Kevin B; Johnson, D Barrie

    2005-02-01

    Mine drainage waters vary considerably in the range and concentration of heavy metals they contain. Besides iron, manganese is frequently present at elevated concentrations in waters draining both coal and metal mines. Passive treatment systems (aerobic wetlands and compost bioreactors) are designed to remove iron by biologically induced oxidation/precipitation. Manganese, however, is problematic as it does not readily form sulfidic minerals and requires elevated pH (>8) for abiotic oxidation of Mn (II) to insoluble Mn (IV). As a result, manganese removal in passive remediation systems is often less effective than removal of iron. This was found to be the case at the pilot passive treatment plant (PPTP) constructed to treat water draining the former Wheal Jane tin mine in Cornwall, UK, where effective removal of manganese occurred only in one of the three rock filter components of the composite systems over a 1-year period of monitoring. Water in the two rock filter systems where manganese removal was relatively poor was generally manganese removal were due to variable performances in the compost bioreactors that feed the rock filter units in the composite passive systems at Wheal Jane. An alternative approach for removing soluble manganese from mine waters, using fixed bed bioreactors, was developed. Ferromanganese nodules (about 2 cm diameter), collected from an abandoned mine adit in north Wales, were used to inoculate the bioreactors (working volume ca. 700 ml). Following colonization by manganese-oxidizing microbes, the aerated bioreactor catalysed the removal of soluble manganese, via oxidation of Mn (II) and precipitation of the resultant Mn (IV) in the bioreactor, in synthetic media and mine water from the Wheal Jane PPTP. Such an approach has potential application for removing soluble Mn from mine streams and other Mn-contaminated water courses. PMID:15680632

  13. Manganese and copper in the root plaque of Phragmites australis (cav. ) trin. ex steudel

    Microsoft Academic Search

    LOUISE ST-CYR; ADELE A. CROWDER

    1990-01-01

    Manganese and copper were found in the iron oxide plaque on roots of Phragmites australis collected at six sampling sites in southern Quebec and Ontario, Canada. Manganese concentration in the plaque, like that of Fe, is correlated with Mn-bound-to-carbonates fraction of the soil\\/sediment. The Fe:Mn ratio of the plaque resemble the same ratio of Fe:Mn-bound-to-carbonates in the substrate. The ratio

  14. Manganese supplementation protects against diet-induced diabetes in wild type mice by enhancing insulin secretion.

    PubMed

    Lee, Soh-Hyun; Jouihan, Hani A; Cooksey, Robert C; Jones, Deborah; Kim, Hyung J; Winge, Dennis R; McClain, Donald A

    2013-03-01

    Mitochondrial dysfunction is both a contributing mechanism and complication of diabetes, and oxidative stress contributes to that dysfunction. Mitochondrial manganese-superoxide dismutase (MnSOD) is a metalloenzyme that provides antioxidant protection. We have previously shown in a mouse model of hereditary iron overload that cytosolic iron levels affected mitochondrial manganese availability, MnSOD activity, and insulin secretion. We therefore sought to determine the metallation status of MnSOD in wild-type mice and whether altering that status affected ?-cell function. 129/SvEVTac mice given supplemental manganese exhibited a 73% increase in hepatic MnSOD activity and increased metallation of MnSOD. To determine whether manganese supplementation offered glucose homeostasis under a situation of ?-cell stress, we challenged C57BL/6J mice, which are more susceptible to diet-induced diabetes, with a high-fat diet for 12 weeks. Manganese was supplemented or not for the final 8 weeks on that diet, after which we examined glucose tolerance and the function of isolated islets. Liver mitochondria from manganese-injected C57BL/6J mice had similar increases in MnSOD activity (81%) and metallation as were seen in 129/SvEVTac mice. The manganese-treated group fed high fat had improved glucose tolerance (24% decrease in fasting glucose and 41% decrease in area under the glucose curve), comparable with mice on normal chow and increased serum insulin levels. Isolated islets from the manganese-treated group exhibited improved insulin secretion, decreased lipid peroxidation, and improved mitochondrial function. In conclusion, MnSOD metallation and activity can be augmented with manganese supplementation in normal mice on normal chow, and manganese treatment can increase insulin secretion to improve glucose tolerance under conditions of dietary stress. PMID:23372018

  15. Investigation of cadmium resistance in an Alcaligenes sp

    SciTech Connect

    McEntee, J.D.; Woodrow, J.R.; Quirk, A.V.

    1986-03-01

    The mechanisms of metal resistance of a cadmium-resistant Alcaligenes sp. were studied. Growth in a defined medium was unaffected by cadmium at concentrations up to 0.1 mM, while at concentrations up to 2.5 mM, growth occurred after an extended lag phase. The increase in length of the lag phase was abolished by repeated subculturing at these higher concentrations. However, subculture in the absence of cadmium reversed the adaptation process. Plasmid DNA was not detected in adapted cells, suggesting that adaptation is not plasmid mediated. Increased sulfide production in response to cadmium was observed, although the levels were too low to account fully for cadmium resistance. Adaptation of cells to cadmium resulted in the appearance of a major new membrane preparation. This protein was induced at cadmium concentrations of 0.1 mM and above, but below this level the protein was absent. The onset of growth at concentrations above 0.1 mM was coincident with the appearance of this protein, which was also induced by zinc (0.4 mM) but not by manganese or nickel. The protein was only solubilized by a sodium dodecyl sulfate-2-mercaptoethanol mixture. Similar solubility properties were shown by a second major membrane protein (molecular weight, 33,000). These two proteins proved to be similar by peptide-mapping experiments and amino acid analysis. The appearance of the 34,500-molecular-weight protein and its possible role in cadmium resistance are discussed.

  16. Process for removing technetium from iron and other metals

    DOEpatents

    Leitnaker, J.M.; Trowbridge, L.D.

    1999-03-23

    A process for removing technetium from iron and other metals comprises the steps of converting the molten, alloyed technetium to a sulfide dissolved in manganese sulfide, and removing the sulfide from the molten metal as a slag. 4 figs.

  17. Process for removing technetium from iron and other metals

    DOEpatents

    Leitnaker, James M. (Kingston, TN); Trowbridge, Lee D. (Oak Ridge, TN)

    1999-01-01

    A process for removing technetium from iron and other metals comprises the steps of converting the molten, alloyed technetium to a sulfide dissolved in manganese sulfide, and removing the sulfide from the molten metal as a slag.

  18. 21 CFR 582.5455 - Manganese glycerophosphate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Manganese glycerophosphate. 582.5455 Section...or Dietary Supplements 1 § 582.5455 Manganese glycerophosphate. (a) Product. Manganese glycerophosphate. (b) Conditions...

  19. 21 CFR 582.5455 - Manganese glycerophosphate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Manganese glycerophosphate. 582.5455 Section...or Dietary Supplements 1 § 582.5455 Manganese glycerophosphate. (a) Product. Manganese glycerophosphate. (b) Conditions...

  20. 21 CFR 582.5455 - Manganese glycerophosphate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Manganese glycerophosphate. 582.5455 Section...or Dietary Supplements 1 § 582.5455 Manganese glycerophosphate. (a) Product. Manganese glycerophosphate. (b) Conditions...

  1. 21 CFR 582.5455 - Manganese glycerophosphate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Manganese glycerophosphate. 582.5455 Section...or Dietary Supplements 1 § 582.5455 Manganese glycerophosphate. (a) Product. Manganese glycerophosphate. (b) Conditions...

  2. 21 CFR 582.5455 - Manganese glycerophosphate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Manganese glycerophosphate. 582.5455 Section...or Dietary Supplements 1 § 582.5455 Manganese glycerophosphate. (a) Product. Manganese glycerophosphate. (b) Conditions...

  3. Cadmium - A metallohormone?

    SciTech Connect

    Byrne, Celia [Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC (United States); Divekar, Shailaja D.; Storchan, Geoffrey B.; Parodi, Daniela A. [Department of Biochemistry and Molecular and Cellular Biology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC (United States); Martin, Mary Beth [Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC (United States); Department of Biochemistry and Molecular and Cellular Biology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC (United States)], E-mail: martinmb@georgetown.edu

    2009-08-01

    Cadmium is a heavy metal that is often referred to as the metal of the 20th century. It is widely used in industry principally in galvanizing and electroplating, in batteries, in electrical conductors, in the manufacture of alloys, pigments, and plastics, and in the stabilization of phosphate fertilizers. As a byproduct of smelters, cadmium is a prevalent environmental contaminant. In the general population, exposure to cadmium occurs primarily through dietary sources, cigarette smoking, and, to a lesser degree, drinking water. Although the metal has no known physiological function, there is evidence to suggest that the cadmium is a potent metallohormone. This review summarizes the increasing evidence that cadmium mimics the function of steroid hormones, addresses our current understanding of the mechanism by which cadmium functions as a hormone, and discusses its potential role in development of the hormone dependent cancers.

  4. Cadmium Toxicity and Treatment

    PubMed Central

    Bernhoft, Robin A.

    2013-01-01

    Cadmium is a heavy metal of considerable toxicity with destructive impact on most organ systems. It is widely distributed in humans, the chief sources of contamination being cigarette smoke, welding, and contaminated food and beverages. Toxic impacts are discussed and appear to be proportional to body burden of cadmium. Detoxification of cadmium with EDTA and other chelators is possible and has been shown to be therapeutically beneficial in humans and animals when done using established protocols. PMID:23844395

  5. Hot coal gas desulfurization with manganese based sorbents. Quarterly report, June--September 1994

    SciTech Connect

    Hepworth, M.T.; Slimane, R.B.

    1994-11-01

    The focus of work being performed on hot coal gas desulfurization at the Morgantown Energy Technology Center is primarily in the use of zinc titanate sorbents; however, prior studies indicated that an alternate sorbent, manganese dioxide-containing ore in mixture with alumina (75 wt% ore + 25 wt% Al{sub 2}O{sub 3}) appears to be a strong contender to zinc-based sorbents. Manganese, for example, has a lower vapor pressure in the elemental state than zinc; hence, it is not as likely to undergo zinc-depletion from the sorbent surface upon loading and regeneration cycles. Also manganese oxide is less readily reduced to the elemental state than iron; hence, the range of reduction potentials for oxygen is somewhat greater than for zinc ferrite. In addition, thermodynamic analysis of the manganese-oxygen-sulfur system shows it to be less amenable to sulfation than zinc ferrite. Also manganese chlorides are much less stable and volatile than zinc chlorides. Potential also exists for utilization of manganese at higher temperatures than zinc ferrite or zinc titanate. This Eighth Quarterly Report documents progress in pelletizing and testing via thermo-gravimetric analysis of individual pellet formulations of manganese ore/alumina combinations and also manganese carbonate/alumina with two binders, dextrin and bentonite.

  6. Lipid peroxidation in rat adrenal glands after administration cadmium and role of essential metals.

    PubMed

    Yiin, S J; Sheu, J Y; Lin, T H

    2001-01-12

    The aim of this study was to investigate the effects of cadmium-induced peroxidative damage to rat adrenals. Cadmium significantly increased adrenal lipid peroxidation in a dose- and time-related manner. Cadmium-induced lipid peroxidation was accompanied by a marked elevation in adrenal iron (Fe) levels, in particular the free elemental form. Chelation of Fe with deferoxamine decreased the cadmium effect on lipid peroxidation. Selenium (Se) was also effective in inhibiting Cd-induced adrenal lipid peroxidation. Data indicate that Cd-induced lipid peroxidation in rat adrenals may be dependent upon Fe and Se levels in this tissue. PMID:11205535

  7. Cadmium exposure and nephropathy in a 28-year-old female metals worker.

    PubMed Central

    Wittman, Richard; Hu, Howard

    2002-01-01

    A 28-year-old female presented for evaluation of left flank pain and polyuria after having been exposed to cadmium in the jewelry manufacturing industry for approximately 3 years. This patient possessed both elevated 24-hr urinary ss2-microglobulin and elevated blood cadmium levels. Approximately 6 months after initial presentation, the patient resigned from her job due to shortness of breath, chest pain, and anxiety. Exposure to cadmium in the jewelry industry is a significant source of occupational cadmium exposure. Other occupational sources include the manufacture of nickel-cadmium batteries, metal plating, zinc and lead refining, smelting of cadmium and lead, and production of plastics. Cadmium is also an environmental pollutant that accumulates in leafy vegetables and plants, including tobacco. Major toxicities anticipated from cadmium exposure involve the renal, pulmonary, and, to a lesser extent, gastrointestinal systems. These include the development of renal proximal tubular dysfunction, glomerular damage with progressive renal disease, and respiratory symptoms including pneumonitis and emphysema. Low-level cadmium exposure has also been associated with increased urinary calcium excretion and direct bone toxicity, effects that recent research suggests may result in the development of osteoporosis. The body burden of cadmium, over half of which may reside in the kidneys, is most often measured through the use of urinary cadmium levels. Blood cadmium measurements generally reflect current or recent exposure and are especially useful in cases with a short exposure period and only minimal accumulation of cadmium in the kidneys. Both ss2-microglobulin and alpha1-microglobulin serve as organ-specific, early-effect biomarkers of tubular proteinuria and thus play a role in identifying early signs of cadmium-induced renal damage in those with potential exposures. In addition to ensuring workplace compliance with Occupational Safety and Health Administration-mandated monitoring and screening measures, it is prudent for those with cadmium exposure to maintain adequate intake of both iron and calcium, appropriate measures even in the absence of exposure. PMID:12460807

  8. Process for producing cadmium sulfide on a cadmium telluride surface

    DOEpatents

    Levi, D.H.; Nelson, A.J.; Ahrenkiel, R.K.

    1996-07-30

    A process is described for producing a layer of cadmium sulfide on a cadmium telluride surface to be employed in a photovoltaic device. The process comprises providing a cadmium telluride surface which is exposed to a hydrogen sulfide plasma at an exposure flow rate, an exposure time and an exposure temperature sufficient to permit reaction between the hydrogen sulfide and cadmium telluride to thereby form a cadmium sulfide layer on the cadmium telluride surface and accomplish passivation. In addition to passivation, a heterojunction at the interface of the cadmium sulfide and the cadmium telluride can be formed when the layer of cadmium sulfide formed on the cadmium telluride is of sufficient thickness. 12 figs.

  9. Manganese concentrations in soil and settled dust in an area with historic ferroalloy production.

    PubMed

    Pavilonis, Brian T; Lioy, Paul J; Guazzetti, Stefano; Bostick, Benjamin C; Donna, Filippo; Peli, Marco; Zimmerman, Neil J; Bertrand, Patrick; Lucas, Erika; Smith, Donald R; Georgopoulos, Panos G; Mi, Zhongyuan; Royce, Steven G; Lucchini, Roberto G

    2014-10-22

    Ferroalloy production can release a number of metals into the environment, of which manganese (Mn) is of major concern. Other elements include lead, iron, zinc, copper, chromium, and cadmium. Mn exposure derived from settled dust and suspended aerosols can cause a variety of adverse neurological effects to chronically exposed individuals. To better estimate the current levels of exposure, this study quantified the metal levels in dust collected inside homes (n=85), outside homes (n=81), in attics (n=6), and in surface soil (n=252) in an area with historic ferroalloy production. Metals contained in indoor and outdoor dust samples were quantified using inductively coupled plasma optical emission spectroscopy, whereas attic and soil measurements were made with a X-ray fluorescence instrument. Mean Mn concentrations in soil (4600??g/g) and indoor dust (870??g/g) collected within 0.5?km of a plant exceeded levels previously found in suburban and urban areas, but did decrease outside 1.0?km to the upper end of background concentrations. Mn concentrations in attic dust were ~120 times larger than other indoor dust levels, consistent with historical emissions that yielded high airborne concentrations in the region. Considering the potential health effects that are associated with chronic Mn inhalation and ingestion exposure, remediation of soil near the plants and frequent, on-going hygiene indoors may decrease residential exposure and the likelihood of adverse health effects.Journal of Exposure Science and Environmental Epidemiology advance online publication, 22 October 2014; doi:10.1038/jes.2014.70. PMID:25335867

  10. Extracellular zinc competitively inhibits manganese uptake and compromises oxidative stress management in Streptococcus pneumoniae.

    PubMed

    Eijkelkamp, Bart A; Morey, Jacqueline R; Ween, Miranda P; Ong, Cheryl-lynn Y; McEwan, Alastair G; Paton, James C; McDevitt, Christopher A

    2014-01-01

    Streptococcus pneumoniae requires manganese for colonization of the human host, but the underlying molecular basis for this requirement has not been elucidated. Recently, it was shown that zinc could compromise manganese uptake and that zinc levels increased during infection by S. pneumoniae in all the niches that it colonized. Here we show, by quantitative means, that extracellular zinc acts in a dose dependent manner to competitively inhibit manganese uptake by S. pneumoniae, with an EC50 of 30.2 µM for zinc in cation-defined media. By exploiting the ability to directly manipulate S. pneumoniae accumulation of manganese, we analyzed the connection between manganese and superoxide dismutase (SodA), a primary source of protection for S. pneumoniae against oxidative stress. We show that manganese starvation led to a decrease in sodA transcription indicating that expression of sodA was regulated through an unknown manganese responsive pathway. Intriguingly, examination of recombinant SodA revealed that the enzyme was potentially a cambialistic superoxide dismutase with an iron/manganese cofactor. SodA was also shown to provide the majority of protection against oxidative stress as a S. pneumoniae ?sodA mutant strain was found to be hypersensitive to oxidative stress, despite having wild-type manganese levels, indicating that the metal ion alone was not sufficiently protective. Collectively, these results provide a quantitative assessment of the competitive effect of zinc upon manganese uptake and provide a molecular basis for how extracellular zinc exerts a 'toxic' effect on bacterial pathogens, such as S. pneumoniae. PMID:24558498

  11. Column solid phase extraction and flame atomic absorption spectrometric determination of manganese(II) and iron(III) ions in water, food and biological samples using 3-(1-methyl-1H-pyrrol-2-yl)-1H-pyrazole-5-carboxylic acid on synthesized graphene oxide.

    PubMed

    Pourjavid, Mohammad Reza; Sehat, Ali Akbari; Arabieh, Masoud; Yousefi, Seyed Reza; Hosseini, Majid Haji; Rezaee, Mohammad

    2014-02-01

    A modified, selective, highly sensitive and accurate procedure for the determination of trace amounts of manganese and iron ions is established in the presented work. 3-(1-Methyl-1H-pyrrol-2-yl)-1H-pyrazole-5-carboxylic acid (MPPC) and graphene oxide (GO) were used in a glass column as chelating reagent and as adsorbent respectively prior to their determination by flame atomic absorption spectrometry. The adsorption mechanism of titled metals complexes on GO was investigated by using computational chemistry approach based on PM6 semi-empirical potential energy surface (PES). The effect of some parameters including pH, flow rate and volume of sample and type, volume and concentration of eluent, as well as the adsorption capacity of matrix ions on the recovery of Mn(II) and Fe(III) was investigated. The limit of detection was 145 and 162 ng L(-1) for Mn(II) and Fe(III), respectively. Calibration was linear over the range of 0.31-355 ?g L(-1) for Mn(II) and 0.34-380 ?g L(-1) for Fe(III) ions. The method was successfully applied for the determination of understudied ions in water, food and biological samples. PMID:24411390

  12. The manganese toxicity of cotton.

    PubMed

    Sirkar, S; Amin, J V

    1974-10-01

    Cotton plants (Gossypium hirsutum. Linn. var. Sankar 4) were grown at normal and toxic levels of substrate manganese, and the altered metabolism of manganese toxic plants was studied. The tissues of plants exposed to toxic levels of manganese had higher activities of peroxidase and polyphenol oxidase, and the activities of catalase, ascorbic acid oxidase, glutathione oxidase and cytochrome c oxidase were lowered. In addition, the high manganese tissue had lower contents of ATP and glutathione but higher amounts of ascorbic acid. The respiration of the partially expanded leaves and the growing tips of toxic plants were depressed when compared to that of the normal tissues. The metabolic changes of manganese toxicity of cotton are placed in the following order: accumulation of manganese in the leaf tissue; a rise in respiration; stimulation of polyphenol oxidase; the appearance of initial toxicity symptoms; the evolution of ethylene and stimulation of peroxidase; the presence of severe toxicity symptoms; the depression of terminal oxidases and respiration; abscission of the growing tip and proliferation of the stem tissue. The early stimulation of polyphenol oxidase may be used to detect potential manganese toxicity. PMID:16658924

  13. Study of hazardous metals in iron slag waste using laser induced breakdown spectroscopy.

    PubMed

    Gondal, M A; Hussain, T; Yamani, Z H; Bakry, A H

    2007-05-01

    Laser Induced Breakdown Spectroscopy (LIBS) was applied for quantitative elemental analysis of slag samples collected from a local steel plant using an Nd: YAG laser emitting radiation at 1064 nm wavelength. The concentration of different elements of environmental significance such as cadmium, calcium, sulfur, magnesium, chromium, manganese, titanium, barium, phosphorus and silicon were 44, 2193, 1724,78578, 217260, 22220, 5178, 568, 2805, 77871 were mg Kg-1, respectively. Optimal experimental conditions for analysis were investigated. The calibration curves were drawn for different elements. The concentrations determined with our Laser-Induced Breakdown Spectrometers were compared with the results obtained using Inductively Coupled Plasma (ICP) emission spectroscopy. Our study demonstrates that LIBS could be highly appropriate for rapid online analysis of iron slag waste. The relative accuracy of our LIBS system for various elements as compared with ICP method is in the range of 0.001-0.049 at 2.5% error confidence. Limits of detection (LOD) of our LIBS system were also estimated for the elements noted here. The hazardous effects of some of the trace elements present in iron slag exceeding permissible safe limits are also discussed. PMID:17474003

  14. Distribution of available manganese in Kentucky soils

    Microsoft Academic Search

    J. L. Sims; P. Duangpatra; J. H. Ellis; R. E. Phillips

    1979-01-01

    Laboratory studies were conducted to determine fractions of native soil and applied manganese 54 that contribute to the manganese extracted by DTPA (0.005 M diethylenetriamine pentaacetic acid, 0.005 M CaClâ, 0.1 M triethanolamine, pH 7.3). Since DTPA-extractable manganese is closely related to manganese uptake by plants, such studies should provide information about fractions of soil manganese that contribute most to

  15. Environmental cadmium in Europe.

    PubMed

    Jensen, A; Bro-Rasmussen, F

    1992-01-01

    The present article reviews information from the latest 10 years concerning fate and exposure of cadmium in the environment, on ecotoxicological effects, and on critical pathways leading to human and environmental exposure. It emphasizes the situation within the Community of European Countries by referring to limit values used in the EEC and some of its member states for emissions to water, air and soil. Estimates have been made on total emission balances for the Netherlands, Denmark, and for the EEC as a whole. The balances show that 70-90% of all cadmium circulating in the Community is disposed of as waste in solid waste deposits. Production and use patterns are presently changing, as indicated by reduced consumption in recent years of cadmium for plating, stabilizers and pigments in several countries as a result of regulations. However, significant increases in consumption for cadmium-containing batteries have occurred, resulting globally in increasing trends for the total consumption and production. Cadmium in sediments is more mobile than described earlier. Aquatic organisms can be classified in order of decreasing accumulation: algae greater than molluscs greater than crustaceans greater than fish. There is no evidence of biomagnification of cadmium within marine or fresh water food webs. Cadmium may enter into plants via roots or by foliar adsorption following atmospheric deposition. Biomagnification in terrestrial food chains is not observed. The uptake into plants is plant specific. Within plants significant variations are seen with concentrations generally decreasing in the order: roots greater than leaves greater than fruiting parts greater than seeds. A compilation of cadmium in air, in the aquatic environment and in soil is given. A downward trend during the 1970s to mid-1980s seems to be evidenced from various Northern European studies on cadmium air concentrations as well as for deposition rates of cadmium. In rivers, the dissolved cadmium concentrations are generally found to be relatively low (10-500 ng/L). In seawater, cadmium concentrations are found at 0.5-10 ng/L in oceanic or open marine areas, while elevated concentrations are reported in more closed marine areas and especially in coastal zones close to polluted estuaries. In fresh water, lake sediments concentrations 3-30 times higher than the background concentrations are reported in the surface layers of sediments. A significant decrease in such pollution has been observed within the recent 10 years. For marine sediments, enrichment factors of two are found in sediments from open areas and locally even 5-10 times.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:1509176

  16. Manganese waste water treatment by fungi derived from manganese slag.

    PubMed

    Ou-Yang, Yu-Zhu; Cao, Jian-Bing; Li, Xiao-Ming; Zheng, Wei; Wang, Dong-Bo; Zhang, Yi

    2010-01-01

    The aim of this study was to isolate a mould from the surface of manganese slag which had strong resistance and high adsorption of Mn(2 + ), and to determine the effects of initial Mn(2 + ) concentration, incubation temperature, rotation speed and inoculation amount on adsorption of Mn(2 + ) from manganese waste water solution. The result showed that a mould (A5) which was isolated from manganese slag had the adsorption rate of Mn(2 + ) to 97.5% at the initial pH value 6, inoculation amount 2%, rotation speed 150 r/min, a concentration of Mn(2 + ) 500 mg/L, and a temperature of 28 degrees C cultivated for 50 h. As there is no research on adsorption of Mn(2 + ) from manganese waste water by fungi before, this research showed a theoretical guidance on this field. PMID:20818063

  17. Tellurium content of marine manganese oxides and other manganese oxides

    USGS Publications Warehouse

    Lakin, H.W.; Thompson, C.E.; Davidson, D.F.

    1963-01-01

    Tellurium in amounts ranging from 5 to 125 parts per million was present in all of 12 samples of manganese oxide nodules from the floor of the Pacific and Indian oceans. These samples represent the first recognized points of high tellurium concentration in a sedimentary cycle. The analyses may lend support to the theory that the minor-element content of seafloor manganese nodules is derived from volcanic emanations.

  18. Influence of welding fume on systemic iron status.

    PubMed

    Casjens, Swaantje; Henry, Jana; Rihs, Hans-Peter; Lehnert, Martin; Raulf-Heimsoth, Monika; Welge, Peter; Lotz, Anne; Gelder, Rainer Van; Hahn, Jens-Uwe; Stiegler, Hugo; Eisele, Lewin; Weiss, Tobias; Hartwig, Andrea; Brüning, Thomas; Pesch, Beate

    2014-11-01

    Iron is the major metal found in welding fumes, and although it is an essential trace element, its overload causes toxicity due to Fenton reactions. To avoid oxidative damage, excess iron is bound to ferritin, and as a result, serum ferritin (SF) is a recognized biomarker for iron stores, with high concentrations linked to inflammation and potentially also cancer. However, little is known about iron overload in welders. Within this study, we assessed the iron status and quantitative associations between airborne iron, body iron stores, and iron homeostasis in 192 welders not wearing dust masks. Welders were equipped with personal samplers in order to determine the levels of respirable iron in the breathing zone during a working shift. SF, prohepcidin and other markers of iron status were determined in blood samples collected after shift. The impact of iron exposure and other factors on SF and prohepcidin were estimated using multiple regression models. Our results indicate that respirable iron is a significant predictor of SF and prohepcidin. Concentrations of SF varied according to the welding technique and respiratory protection used, with a median of 103 ?g l(-1) in tungsten inert gas welders, 125 ?g l(-1) in those wearing air-purifying respirators, and 161 ?g l(-1) in other welders. Compared to welders with low iron stores (SF < 25 ?g l(-1)), those with excess body iron (SF ? 400 ?g l(-1)) worked under a higher median concentration of airborne iron (60 ?g m(-3) versus 148 ?g m(-3)). Even though air concentrations of respirable iron and manganese were highly correlated, and low iron stores have been reported to increase manganese uptake in the gastrointestinal tract, no correlation was seen between SF and manganese in blood. In conclusion, monitoring SF may be a reasonable method for health surveillance of welders. Respiratory protection with air-purifying respirators can decrease iron exposure and avoid chronically higher SF in welders working with high-emission technologies. PMID:25223225

  19. Bioaccumulation of manganese and its toxicity in feral pigeons (Columba livia) exposed to manganese oxide dust (Mn{sub 3}O{sub 4})

    SciTech Connect

    Sierra, P.; Chakrabarti, S.; Tounkara, R.; Loranger, S.; Kennedy, G.; Zayed, J. [Univ. of Montreal (Canada)] [Univ. of Montreal (Canada)

    1998-11-01

    Manganese tetroxide (Mn{sub 3}O{sub 4}) is a product from the combustion of methylcyclopentadienyl manganese tricarbonyl. Exposure to high levels of manganese can lead to serious health effects especially to the central nervous and respiratory systems. Very few studies on the effects of long-term low level exposure to Mn{sub 3}O{sub 4} have been reported. The present study was therefore conducted to examine the bioaccumulation and toxicity of manganese in various organs of feral pigeons (Columba kivia) when exposed to low levels of Mn{sub 3}O{sub 4} via inhalation and hence to find any possible relationship between these two parameters. A total of 22 pigeons was exposed to 239 {micro}g/m{sup 3} of manganese for 7 h/day, 5 days/week for 5, 9, and 13 consecutive weeks. Manganese concentrations in various tissues, e.g., brain (mesencephalon), lung, liver, intestine, pancreas, kidney, muscle, bone, and whole blood, were measured by neutron activation analysis. Various biochemical parameters in blood, e.g., hematocrit, total proteins, glucose, uric acid, alinine aminotransferase, total iron, blood urea nitrogen and triglycerides, were also measured.

  20. Iron and Iron Deficiency

    MedlinePLUS

    ... from these substances is usually not of concern. Vegetarian diets are low in heme iron, but careful meal ... heme iron sources in the diet (e.g., vegetarian diets) Low absorption Taking antacids beyond the recommended dose ...

  1. FATE OF METHYLCYCLOPENTADIENYL MANGANESE TRICARBONYL

    EPA Science Inventory

    Methylcyclopentadienyl manganese tricarbonyl (MMT) has been proposed as an octane booster for unleaded gasoline; such use could result in ecological and human exposure through surface water and ground water ecosystems. o evaluate the environmental risks from MMT, its environmenta...

  2. Trace Metal Associations with Manganese-Rich Surface Coatings of Lead Service Lines

    EPA Science Inventory

    Analysis of lead service line samples from U. S. Environmental Protection Agency?s long-term research program to evaluate control and metal release from domestic drinking water service lines has revealed that Manganese-rich solids also contain Iron and sometimes Aluminum have fre...

  3. Mechanisms of cadmium carcinogenicity in the gastrointestinal tract.

    PubMed

    Bishak, Yaser Khaje; Payahoo, Laleh; Osatdrahimi, Alireza; Nourazarian, Alireza

    2015-01-01

    Cancer, a serious public health problem in worldwide, results from an excessive and uncontrolled proliferation of the body cells without obvious physiological demands of organs. The gastrointestinal tract, including the esophagus, stomach and intestine, is a unique organ system. It has the highest cancer incidence and cancer- related mortality in the body and is influenceed by both genetic and environmental factors. Among the various chemical elements recognized in the nature, some of them including zinc, iron, cobalt, and copper have essential roles in the various biochemical and physiological processes, but only at low levels and others such as cadmium, lead, mercury, arsenic, and nickel are considered as threats for human health especially with chronic exposure at high levels. Cadmium, an environment contaminant, cannot be destroyed in nature. Through impairment of vitamin D metabolism in the kidney it causes nephrotoxicity and subsequently bone metabolism impairment and fragility. The major mechanisms involved in cadmium carcinogenesis could be related to the suppression of gene expression, inhibition of DNA damage repair, inhibition of apoptosis, and induction of oxidative stress. In addition, cadmium may act through aberrant DNA methylation. Cadmium affects multiple cellular processes, including signal transduction pathways, cell proliferation, differentiation, and apoptosis. Down-regulation of methyltransferases enzymes and reduction of DNA methylation have been stated as epigenetic effects of cadmium. Furthermore, increasing intracellular free calcium ion levels induces neuronal apoptosis in addition to other deleterious influence on the stability of the genome. PMID:25640397

  4. Novel MntR-Independent Mechanism of Manganese Homeostasis in Escherichia coli by the Ribosome-Associated Protein HflX

    PubMed Central

    Kaur, Gursharan; Sengupta, Sandeepan; Kumar, Vineet; Kumari, Aruna; Ghosh, Aditi; Parrack, Pradeep

    2014-01-01

    Manganese is a micronutrient required for activities of several important enzymes under conditions of oxidative stress and iron starvation. In Escherichia coli, the manganese homeostasis network primarily constitutes a manganese importer (MntH) and an exporter (MntP), which are regulated by the MntR dual regulator. In this study, we find that deletion of E. coli hflX, which encodes a ribosome-associated GTPase with unknown function, renders extreme manganese sensitivity characterized by arrested cell growth, filamentation, lower rate of replication, and DNA damage. We demonstrate that perturbation by manganese induces unprecedented influx of manganese in ?hflX cells compared to that in the wild-type E. coli strain. Interestingly, our study indicates that the imbalance in manganese homeostasis in the ?hflX strain is independent of the MntR regulon. Moreover, the influx of manganese leads to a simultaneous influx of zinc and inhibition of iron import in ?hflX cells. In order to review a possible link of HflX with the ? phage life cycle, we performed a lysis-lysogeny assay to show that the Mn-perturbed ?hflX strain reduces the frequency of lysogenization of the phage. This observation raises the possibility that the induced zinc influx in the manganese-perturbed ?hflX strain stimulates the activity of the zinc-metalloprotease HflB, the key determinant of the lysis-lysogeny switch. Finally, we propose that manganese-mediated autophosphorylation of HflX plays a central role in manganese, zinc, and iron homeostasis in E. coli cells. PMID:24794564

  5. Novel MntR-independent mechanism of manganese homeostasis in Escherichia coli by the ribosome-associated protein HflX.

    PubMed

    Kaur, Gursharan; Sengupta, Sandeepan; Kumar, Vineet; Kumari, Aruna; Ghosh, Aditi; Parrack, Pradeep; Dutta, Dipak

    2014-07-01

    Manganese is a micronutrient required for activities of several important enzymes under conditions of oxidative stress and iron starvation. In Escherichia coli, the manganese homeostasis network primarily constitutes a manganese importer (MntH) and an exporter (MntP), which are regulated by the MntR dual regulator. In this study, we find that deletion of E. coli hflX, which encodes a ribosome-associated GTPase with unknown function, renders extreme manganese sensitivity characterized by arrested cell growth, filamentation, lower rate of replication, and DNA damage. We demonstrate that perturbation by manganese induces unprecedented influx of manganese in ?hflX cells compared to that in the wild-type E. coli strain. Interestingly, our study indicates that the imbalance in manganese homeostasis in the ?hflX strain is independent of the MntR regulon. Moreover, the influx of manganese leads to a simultaneous influx of zinc and inhibition of iron import in ?hflX cells. In order to review a possible link of HflX with the ? phage life cycle, we performed a lysis-lysogeny assay to show that the Mn-perturbed ?hflX strain reduces the frequency of lysogenization of the phage. This observation raises the possibility that the induced zinc influx in the manganese-perturbed ?hflX strain stimulates the activity of the zinc-metalloprotease HflB, the key determinant of the lysis-lysogeny switch. Finally, we propose that manganese-mediated autophosphorylation of HflX plays a central role in manganese, zinc, and iron homeostasis in E. coli cells. PMID:24794564

  6. The Iron Within

    NSDL National Science Digital Library

    2011-02-01

    Forty-fifth monthly installment of our "What A Year!" website project, introducing life science breakthroughs to middle and high school students and their teachers. In order to cause infection, pathogenic bacteria must be able to obtain all the nutrients they need from the human body, including metals such as zinc, iron, and manganese. As a result, many vertebrate species (including humans) have evolved ways to store these metals in forms that are not readily accessible to bacteria. This mechanism is known as nutritional immunity. Staphylococcus aureus has developed such a mechanism, making it a very successful invader.

  7. Hot Coal Gas Desulfurization with manganese based sorbents. Quarterly report, August 1, 1993--September 30, 1993

    SciTech Connect

    Hepworth, M.T.

    1993-10-01

    The focus of work being performed on Hot Coal Gas Desulfurization at the Morgantown Energy Technology Center is primarily in the use of zinc ferrite and zinc titanate sorbents; however, prior studies at the US Steel Fundamental Research Laboratories in Monroeville, PA, by E. T. Turkdogan indicated that an alternate sorbent, manganese dioxide-containing ore in mixture with alumina (75 wt % ore + 25 wt % Al{sub 2}O{sub 3}) may be a viable alternative to zinc-based sorbents. Manganese, for example, has a lower vapor pressure in the elemental state than zinc hence it is not as likely to undergo depletion from the sorbent surface upon loading and regeneration cycles. Also manganese oxide is less readily reduced to the elemental state than iron hence the range of reduction potentials for oxygen is somewhat greater than for zinc ferrite. In addition, thermodynamic analysis of the manganese-oxygen-sulfur system shows it to be less amenable to sulfation than zinc ferrite. Potential also exists for utilization of manganese at higher temperatures than zinc ferrite or zinc titanate. This report documents progress in pelletizing and testing via thermogravimetric analysis of individual pellet formulations of manganese ore/alumina combinations and also manganese carbonate/alumina with two binders, dextrin and bentonite. Preliminary results indicate that the manganese carbonate material, being of higher purity than the manganese ore, has a higher degree of sulfur capacity and more rapid absorption kinetics. A 2-inch fixed-bed reactor has been fabricated and is now ready for subjecting pellets to cyclic loading and regeneration.

  8. Cadmium Transporters in the Kidney and Cadmium-Induced Nephrotoxicity

    PubMed Central

    Yang, Hong; Shu, Yan

    2015-01-01

    Among the organs in which the environmental pollutant cadmium causes toxicity, the kidney has gained the most attention in recent years. Numerous studies have sought to unravel the exact pathways by which cadmium enters the renal epithelial cells and the mechanisms by which it causes toxicity in the kidney. The purpose of this review is to present the progress made on the mechanisms of cadmium transport in the kidney and the role of transporter proteins in cadmium-induced nephrotoxicity. PMID:25584611

  9. Cadmium migration in aerospace nickel cadmium cells

    NASA Technical Reports Server (NTRS)

    Mcdermott, P. P.

    1976-01-01

    The effects of temperature, the nature of separator material, charge and discharge, carbonate contamination, and the mode of storage are studied with respect to the migration of active material from the negative toward the positive plate. A theoretical model is proposed which takes into account the solubility of cadmium in various concentrations of hydroxide and carbonate at different temperatures, the generation of the cadmiate ion, Cd(OH)3(-), during discharge, the migration of the cadmiate ion and particulate Cd(OH)2 due to electrophoretic effects and the movement of electrolyte in and out of the negative plate and, finally, the recrystallization of cadmiate ion in the separator as Cd(OH)2. Application of the theoretical model to observations of cadmium migration in cycled cells is also discussed.

  10. Extraction of manganese from electrolytic manganese residue by bioleaching.

    PubMed

    Xin, Baoping; Chen, Bing; Duan, Ning; Zhou, Changbo

    2011-01-01

    Extraction of manganese from electrolytic manganese residues using bioleaching was investigated in this paper. The maximum extraction efficiency of Mn was 93% by sulfur-oxidizing bacteria at 4.0 g/l sulfur after bioleaching of 9days, while the maximum extraction efficiency of Mn was 81% by pyrite-leaching bacteria at 4.0 g/l pyrite. The series bioleaching first by sulfur-oxidizing bacteria and followed by pyrite-leaching bacteria evidently promoted the extraction of manganese, witnessing the maximum extraction efficiency of 98.1%. In the case of sulfur-oxidizing bacteria, the strong dissolution of bio-generated sulfuric acid resulted in extraction of soluble Mn2+, while both the Fe2+ catalyzed reduction of Mn4+ and weak acidic dissolution of Mn2+ accounted for the extraction of manganese with pyrite-leaching bacteria. The chemical simulation of bioleaching process further confirmed that the acid dissolution of Mn2+ and Fe2+ catalyzed reduction of Mn4+ were the bioleaching mechanisms involved for Mn extraction from electrolytic manganese residues. PMID:21050747

  11. Cadmium Uptake by Aureobasidium pullulans

    Microsoft Academic Search

    J. L. Mowll; G. M. Gadd

    1984-01-01

    Yeast-like cells, mycelium and melanin-pigmented chlamydospores of Aureobasidium pulluluns accumulated cadmium from cadmium-containing medium. With chlamydospores, uptake was rapid and independent of temperature and the presence of glucose, and corresponded to binding of cadmium to cell surfaces. With yeast-like cells and mycelium, the initial rapid surface adsorption of cadmium was up to six times lower than that of chlamydospores, and

  12. Bio-dissolution of spent nickel–cadmium batteries using Thiobacillus ferrooxidans

    Microsoft Academic Search

    C Cerruti; G Curutchet; E Donati

    1998-01-01

    In this study, the production of sulphuric acid in bioreactors with Thiobacillus ferrooxidans attached on elemental sulphur was investigated. These bioreactors reached a maximum H+ productivity of 80 mmol kg?1 d?1 of support. This medium was used for the indirect dissolution of spent nickel–cadmium batteries recovering after 93 days 100% of cadmium, 96.5% of nickel and 95.0% of iron. Moreover,

  13. A manganese-dependent ribozyme in the 3'-untranslated region of Xenopus Vg1 mRNA

    Microsoft Academic Search

    Nikolay G. Kolev; Emilia I. Hartland; Paul W. Huber

    2008-01-01

    The smallest catalytic RNA identified to date is a manganese-dependent ribozyme that requires only a complex between GAAA and UUU to effect site- specific cleavage. We show here that this ribozyme occurs naturally in the 3'-UTR of Vg1 and b-actin mRNAs. In accord with earlier studies with model RNAs, cleavage occurs only in the presence of man- ganese or cadmium

  14. Cadmium biosorption by Saccharomyces cerevisiae

    Microsoft Academic Search

    B. Volesky; H. May; Z. R. Holan

    1993-01-01

    Cadmium uptake by nonliving and resting cells of Saccharomyces cerevisiae obtained from aerobic or anaerobic cultures from pure cadmium-bearing solutions was examined. The highest cadmium uptake exceeding 70 mg Cd\\/g was observed with aerobic baker's yeast biomass from the exponential growth phase. Nearly linear sorption isotherms featured by higher sorbing resting cells together with metal deposits localized exclusively in vacuoles

  15. 21 CFR 184.1449 - Manganese citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...It is obtained by precipitating manganese carbonate from manganese sulfate and sodium carbonate solutions. The filtered and washed precipitate...solution to form manganous citrate and then with sodium citrate to complete the reaction....

  16. 21 CFR 184.1449 - Manganese citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...It is obtained by precipitating manganese carbonate from manganese sulfate and sodium carbonate solutions. The filtered and washed precipitate...solution to form manganous citrate and then with sodium citrate to complete the reaction....

  17. 21 CFR 184.1449 - Manganese citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...It is obtained by precipitating manganese carbonate from manganese sulfate and sodium carbonate solutions. The filtered and washed precipitate...solution to form manganous citrate and then with sodium citrate to complete the reaction....

  18. 21 CFR 184.1449 - Manganese citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...It is obtained by precipitating manganese carbonate from manganese sulfate and sodium carbonate solutions. The filtered and washed precipitate...solution to form manganous citrate and then with sodium citrate to complete the reaction....

  19. 21 CFR 184.1449 - Manganese citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...It is obtained by precipitating manganese carbonate from manganese sulfate and sodium carbonate solutions. The filtered and washed precipitate...solution to form manganous citrate and then with sodium citrate to complete the reaction....

  20. 21 CFR 73.2775 - Manganese violet.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2775 Manganese violet. (a) Identity...Manganese violet is safe for use in coloring cosmetics generally, including cosmetics applied to the area of the eye, in...

  1. 21 CFR 73.2775 - Manganese violet.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2775 Manganese violet. (a) Identity...Manganese violet is safe for use in coloring cosmetics generally, including cosmetics applied to the area of the eye, in...

  2. 21 CFR 73.2775 - Manganese violet.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2775 Manganese violet. (a) Identity...Manganese violet is safe for use in coloring cosmetics generally, including cosmetics applied to the area of the eye, in...

  3. On the manganese content of cosmic flakes from deep-sea sediments

    NASA Technical Reports Server (NTRS)

    Utech, K.

    1973-01-01

    Cosmic flakes belong to the category of cosmic microparticles. They occur together with cosmic spherules in sediments. These flakes appear to represent ablation products of iron meteorites burnt away during the passage of a meteorite through the atmosphere by friction against air molecules. Microprobe analyses of flakes from deep sea deposits proved the particles to consist of magnetite which in most cases had been altered into maghemite in the outer zones. This is in agreement with the assumption that they represent fragments of fusion crust of iron meteorites. Most of the flakes, however, contained a small percentage of manganese. This element is not a common constituent of iron meteorites. An attempt is made to explain the presence of manganese in flakes and its absence in cosmic spherules.

  4. Nickel-cadmium battery recycling through the INMETCO{reg_sign} high temperature metals recovery process

    SciTech Connect

    Liotta, J.J.; Onuska, J.C.; Hanewald, R.H. [INMETCO, Ellwood City, PA (United States)

    1995-07-01

    INMETCO, a subsidiary of Inco Limited, is the only facility in North America that provides the High Temperature Metals Recovery (HTMR) process for nickel-cadmium batteries. In 1993, INMETCO recycled more than 2,200 tons of nickel-cadmium, nickel-iron and nickel metal hydride batteries. The paper describes Inco`s experience in metals recovery, traces the development and explains operation of the HTMR Process and outlines INMETCO`s plans for cadmium recovery at its facility in Ellwood City, Pennsylvania.

  5. Factors influencing intestinal cadmium uptake in pregnant Bangladeshi women-A prospective cohort study

    SciTech Connect

    Kippler, M. [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden)] [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden); Goessler, W. [Institut fuer Chemie-Analytische Chemie, Karl-Franzens-Universitaet, Universitaetsplatz 1, 8010 Graz (Austria)] [Institut fuer Chemie-Analytische Chemie, Karl-Franzens-Universitaet, Universitaetsplatz 1, 8010 Graz (Austria); Nermell, B. [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden)] [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden); Ekstroem, E.C. [Department of Women's and Children's Health, International Maternal and Child Health, Uppsala University, SE-751 85 Uppsala (Sweden)] [Department of Women's and Children's Health, International Maternal and Child Health, Uppsala University, SE-751 85 Uppsala (Sweden); Loennerdal, B. [Department of Nutrition, University of California, Davis, CA 95616 (United States)] [Department of Nutrition, University of California, Davis, CA 95616 (United States); El Arifeen, S. [International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), GPO Box 128, Dhaka 100 (Bangladesh)] [International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), GPO Box 128, Dhaka 100 (Bangladesh); Vahter, M., E-mail: Marie.Vahter@ki.se [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden)

    2009-10-15

    Experimental studies indicate that zinc (Zn) and calcium (Ca) status, in addition to iron (Fe) status, affect gastrointestinal absorption of cadmium (Cd), an environmental pollutant that is toxic to kidneys, bone and endocrine systems. The aim of this study was to evaluate how various nutritional factors influence the uptake of Cd in women, particularly during pregnancy. The study was carried out in a rural area of Bangladesh, where malnutrition is prevalent and exposure to Cd via food appears elevated. The uptake of Cd was evaluated by associations between erythrocyte Cd concentrations (Ery-Cd), a marker of ongoing Cd exposure, and concentrations of nutritional markers. Blood samples, collected in early pregnancy and 6 months postpartum, were analyzed by inductively coupled plasma mass spectrometry (ICPMS). Ery-Cd varied considerably (range: 0.31-5.4 {mu}g/kg) with a median of 1.1 {mu}g/kg (approximately 0.5 {mu}g/L in whole blood) in early pregnancy. Ery-Cd was associated with erythrocyte manganese (Ery-Mn; positively), plasma ferritin (p-Ft; negatively), and erythrocyte Ca (Ery-Ca; negatively) in decreasing order, indicating common transporters for Cd, Fe and Mn. There was no evidence of Cd uptake via Zn transporters, but the association between Ery-Cd and p-Ft seemed to be dependent on adequate Zn status. On average, Ery-Cd increased significantly by 0.2 {mu}g/kg from early pregnancy to 6 months postpartum, apparently due to up-regulated divalent metal transporter 1 (DMT1). In conclusion, intestinal uptake of Cd appears to be influenced either directly or indirectly by several micronutrients, in particular Fe, Mn and Zn. The negative association with Ca may suggest that Cd inhibits the transport of Ca to blood.

  6. Manganese abundances in Galactic bulge red giants

    NASA Astrophysics Data System (ADS)

    Barbuy, B.; Hill, V.; Zoccali, M.; Minniti, D.; Renzini, A.; Ortolani, S.; Gómez, A.; Trevisan, M.; Dutra, N.

    2013-11-01

    Context. Manganese is mainly produced in type II SNe during explosive silicon burning, in incomplete Si-burning regions, and depends on several nucleosynthesis environment conditions, such as mass cut between the matter ejected and falling back onto the remnant, electron and neutron excesses, mixing fallback, and explosion energy. Manganese is also produced in type Ia SNe. Aims: The aim of this work is the study of abundances of the iron-peak element Mn in 56 bulge giants, among which 13 are red clump stars. Four bulge fields along the minor axis are inspected. The study of abundances of Mn-over-Fe as a function of metallicity in the Galactic bulge may shed light on its production mechanisms. Methods: High-resolution spectra were obtained using the FLAMES+UVES spectrograph on the Very Large Telescope. The spectra were obtained within a program to observe 800 stars using the GIRAFFE spectrograph, together with the present UVES spectra. Results: We aim at identifying the chemical evolution of manganese, as a function of metallicity, in the Galactic bulge. We find [Mn/Fe] ~ -0.7 at [Fe/H] ~ -1.3, increasing to a solar value at metallicities close to solar, and showing a spread around - 0.7 ? [Fe/H] ? -0.2, in good agreement with other work on Mn in bulge stars. There is also good agreement with chemical evolution models. We find no clear difference in the behaviour of the four bulge fields. Whereas [Mn/Fe] vs. [Fe/H] could be identified with the behaviour of the thick disc stars, [Mn/O] vs. [O/H] has a behaviour running parallel, at higher metallicities, compared to thick disc stars, indicating that the bulge enrichment might have proceeded differently from that of the thick disc. Observations collected at the European Southern Observatory, Paranal, Chile (ESO programmes 71.B-0617A, 73.B0074A, and GTO 71.B-0196).Tables 1-6 and Figs. 1-6 are available in electronic form at http://www.aanda.org

  7. STRAIN AGING OF AUSTENITIC HADFIELD MANGANESE STEEL

    E-print Network

    Grujicic, Mica

    STRAIN AGING OF AUSTENITIC HADFIELD MANGANESE STEEL W. S. OWEN1 { and M. GRUJICIC2 1 Department. INTRODUCTION Had®eld manganese steel, here represented by the nominal composition Fe±12Mn±1.2C wt%, is a stable. Noting that manganese decreases the activity of carbon in austenite, they speculated that the relatively

  8. Heteroepitaxial Nucleation and Oriented Growth of Manganese

    E-print Network

    Heteroepitaxial Nucleation and Oriented Growth of Manganese Oxide Islands on Carbonate Minerals and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 Manganese redox cycling study, Mn2+(aq) is reacted with O2(aq) at circumneutral pH to form manganese oxide islands on the (101h4

  9. Original article Studies on differential manganese tolerance

    E-print Network

    Boyer, Edmond

    Original article Studies on differential manganese tolerance of mung bean and rice genotypes germinated and grown in the presence of manganese under controlled environmental conditions. Standard growth tested as markers of manganese toxicity. Measurements as early as 48 hours after the germination did

  10. Original article Intestinal transfer of manganese

    E-print Network

    Paris-Sud XI, Université de

    Original article Intestinal transfer of manganese: resemblance to and competition with calcium Y of calcium, phosphate and the sugars lactose and sorbitol on the intestinal absorption of manganese were / Ca lglucides / phosphates #12;INTRODUCTION The intestinal transport of manganese seems very similar

  11. Manganese depresses rat heart muscle respiration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It has previously been reported that moderately high dietary manganese (Mn) in combination with marginal magnesium (Mg) resulted in ultrastructural damage to heart mitochondria. Manganese may replace Mg in biological functions, including the role of enzyme cofactor. Manganese may accumulate and subs...

  12. Manganese oxide cathodes for rechargeable batteries

    Microsoft Academic Search

    Dongmin Im

    2002-01-01

    Manganese oxides are considered as promising cathodes for rechargeable batteries due to their low cost and low toxicity as well as the abundant natural resources. In this dissertation, manganese oxides have been investigated as cathodes for both rechargeable lithium and alkaline batteries. Nanostructured lithium manganese oxides designed for rechargeable lithium cells have been synthesized by reducing lithium permanganate with methanol

  13. Mortality of copper cadmium alloy workers with special reference to lung cancer and non-malignant diseases of the respiratory system, 1946-92

    Microsoft Academic Search

    T Sorahan; A Lister; M S Gilthorpe; J M Harrington

    1995-01-01

    OBJECTIVES--To identify and quantify any relations between occupational exposure to cadmium oxide fume and mortalities from lung cancer and from chronic non-malignant diseases of the respiratory system. METHODS--The mortality experience of 347 copper cadmium alloy workers, 624 workers employed in the vicinity of copper cadmium alloy work (vicinity workers), and 521 iron and brass foundry workers (all men) was investigated

  14. Mineral of the month: cadmium

    USGS Publications Warehouse

    Klimasauskas, Edward

    2005-01-01

    Cadmium, which was once used almost exclusively for pigments, now has many diverse applications. Cadmium’s low melting point, excellent electrical conductivity and resistance to corrosion make it valuable for many products including batteries, electroplated coatings, stabilizers for plastics, solar cells and nonferrous alloys. Today’s cadmium is primarily used in rechargeable batteries, accounting for about 78 percent of consumption in 2004. In 2000, an estimated 3.5 billion consumer batteries were sold in the United States, of which almost 10 percent were nickel-cadmium batteries.

  15. [Carcinogenic activity of nickel-containing welding aerosols in relation to their copper and manganese content].

    PubMed

    Gorba'n, L N; Novichenko, N L; Riazanov, A V; Cherednichenko, V M

    1989-01-01

    Chronic experiments on animals showed that aerosols formed during cast iron welding and facing due to the use of electrode nickel-based materials could produce blastomogenic effect that was mostly caused by the presence of copper-and manganese-containing aerosols in the particles of the solid component. Morphologic inhomogeneity of the particles of the solid component, qualitative composition and solubility of the compounds spatially arranged in the surface layer were of great importance for their carcinogenic and toxic effect. The capacity of copper- and manganese-containing compounds to suppress nickel carcinogenic effect should be taken into account when developing welding and facing materials with better hygienic characteristics. PMID:2630394

  16. Iron and Steel Phosphate Rock

    E-print Network

    Torgersen, Christian

    Abrasives Aluminum Antimony Arsenic Asbestos Barite Bauxite Beryllium Bismuth Boron Bromine Cadmium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Bromine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Cadmium

  17. [Acute and chronic cadmium poisoning].

    PubMed

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

    2010-02-01

    Cadmium is a metallic impurity in various minerals. The two main cadmium exposure sources in general population are food and tobacco smoking. Its industrial exploitation has grown in the early twentieth century. Cadmium is used in accumulators or alkaline batteries (80%) and in pigments for paints or plastics (10%), in electrolytic process by deposit or by cadmium plating on metals or to reduce melting points (welding rods...). Cadmium is a cumulative toxic substance whose half-time for elimination is about 20 to 40 years and it is mainly stored in the liver and kidneys. Inhalation of cadmium oxide fumes may cause inhalation fevers or chemical pneumonitis. Cadmium chronic poisoning causes mainly renal tubulopathy and could be the cause of osteomalacia and diffuse osteoporosis. Cadmium is classified as certain carcinogen agent for humans by International Agency for Research on Cancer (IARC). The most relevant biological index exposure is the urinary cadmium. According to literature, no chelating agent can be still used in human cadmium poisonings. In France, some diseases caused by occupational exposure to cadmium may be compensated. PMID:19709784

  18. Olfactory ferric and ferrous iron absorption in iron-deficient rats

    PubMed Central

    Ruvin Kumara, V. M.

    2012-01-01

    The absorption of metals from the nasal cavity to the blood and the brain initiates an important route of occupational exposures leading to health risks. Divalent metal transporter-1 (DMT1) plays a significant role in the absorption of intranasally instilled manganese, but whether iron uptake would be mediated by the same pathway is unknown. In iron-deficient rats, blood 59Fe levels after intranasal administration of the radioisotope in the ferrous form were significantly higher than those observed for iron-sufficient control rats. Similar results were obtained when ferric iron was instilled intranasally, and blood levels of 59Fe were even greater in the iron-deficient rats compared with the amount of ferrous iron absorbed. Experiments with Belgrade (b/b) rats showed that DMT1 deficiency limited ferric iron uptake from the nasal cavity to the blood compared with +/b controls matched for iron deficiency. These results indicate that olfactory uptake of ferric iron by iron-deficient rats involves DMT1. Western blot experiments confirmed that DMT1 levels are significantly higher in iron-deficient rats compared with iron-sufficient controls in olfactory tissue. Thus the molecular mechanism of olfactory iron absorption is regulated by body iron status and involves DMT1. PMID:22492739

  19. Process for removing and detoxifying cadmium from scrap metal including mixed waste

    SciTech Connect

    Kronberg, J.W.

    1994-07-01

    Cadmium-bearing scrap from nuclear applications, such as neutron shielding and reactor control and safety rods, must usually be handled as mixed waste since it is radioactive and the cadmium in it is both leachable and highly toxic. Removing the cadmium from this scrap, and converting it to a nonleachable and minimally radioactive form, would greatly simplify disposal or recycling. A process now under development will do this by shredding the scrap; leaching it with reagents which selectively dissolve out the cadmium; reprecipitating the cadmium as its highly insoluble sulfide; then fusing the sulfide into a glassy matrix to bring its leachability below EPA limits before disposal. Alternatively, the cadmium may be recovered for reuse. A particular advantage of the process is that all reagents (except the glass frit) can easily be recovered and reused in a nearly closed cycle, minimizing the risk of radioactive release. The process does not harm common metals such as aluminum, iron and stainless steel, and is also applicable to non-nuclear cadmium-bearing scrap such as nickel-cadmium batteries.

  20. Seafood intake and blood cadmium in a cohort of adult avid seafood consumers.

    PubMed

    Guan, Stanford; Palermo, Tia; Meliker, Jaymie

    2015-01-01

    Although the benefits of fish consumption are widely recognized, seafood may also be a source of exposure to heavy metals such as cadmium. Many types of seafood are rich in cadmium, but bioavailability and potential for toxicity after consumption is less clear. This study investigates the relationship between seafood intake and the level of cadmium (Cd) in the blood in a 252 person cohort of avid seafood consumers in the Long Island Study of Seafood Consumption (New York). Blood cadmium is an established biomarker of cadmium exposure, reflecting both recent and decade-long exposure. Data on the amounts and frequency of eating various types of seafood were self-reported by avid seafood consumers recruited in 2011-2012. After adjusting for age, BMI, sex, current smoking status, and income in a linear regression model, we found no association between regular seafood intake (?=-0.01; p=0.11) but did identify an association between salmon intake in cups/week (ln transformed) (?=0.20; p=0.001) and blood cadmium. After accounting for salmon, no other types of seafood were meaningfully associated with blood cadmium. No association was found between rice intake, blood zinc, or dietary iron or calcium and blood cadmium. Results suggest that seafood is not a major source of cadmium exposure, but that salmon intake does marginally increase blood cadmium levels. Given that cadmium levels in salmon are not higher than those in many other seafood species, the association with salmon intake is likely attributed to higher consumption of salmon in this population. PMID:25311854

  1. Cadmium plating replacements

    NASA Technical Reports Server (NTRS)

    Nelson, Mary J.; Groshart, Earl C.

    1995-01-01

    The Boeing Company has been searching for replacements to cadmium plate. Two alloy plating systems seem close to meeting the needs of a cadmium replacement. The two alloys, zinc-nickel and tin-zinc are from alloy plating baths; both baths are neutral pH. The alloys meet the requirements for salt fog corrosion resistance, and both alloys excel as a paint base. Currently, tests are being performed on standard fasteners to compare zinc-nickel and tin-zinc on threaded hardware where cadmium is heavily used. The Hydrogen embrittlement propensity of the zinc-nickel bath has been tested, and just beginning for the tin-zinc bath. Another area of interest is the electrical properties on aluminum for tin-zinc and will be discussed. The zinc-nickel alloy plating bath is in production in Boeing Commercial Airplane Group for non-critical low strength steels. The outlook is promising that these two coatings will help The Boeing Company significantly reduce its dependence on cadmium plating.

  2. Cadmium plating replacements

    SciTech Connect

    Nelson, M.J.; Groshart, E.C.

    1995-03-01

    The Boeing Company has been searching for replacements to cadmium plate. Two alloy plating systems seem close to meeting the needs of a cadmium replacement. The two alloys, zinc-nickel and tin-zinc are from alloy plating baths; both baths are neutral pH. The alloys meet the requirements for salt fog corrosion resistance, and both alloys excel as a paint base. Currently, tests are being performed on standard fasteners to compare zinc-nickel and tin-zinc on threaded hardware where cadmium is heavily used. The Hydrogen embrittlement propensity of the zinc-nickel bath has been tested, and just beginning for the tin-zinc bath. Another area of interest is the electrical properties on aluminum for tin-zinc and will be discussed. The zinc-nickel alloy plating bath is in production in Boeing Commercial Airplane Group for non-critical low strength steels. The outlook is promising that these two coatings will help The Boeing Company significantly reduce its dependence on cadmium plating.

  3. Essential and nonessential elements in nestling rooks Corvus frugilegus from eastern Poland with a special emphasis on their high cadmium contamination.

    PubMed

    Or?owski, Grzegorz; Kami?ski, Piotr; Kasprzykowski, Zbigniew; Zawada, Zbigniew; Koim-Puchowska, Beata; Szady-Grad, Ma?gorzata; Klawe, Jacek J

    2012-11-01

    Concentration of minerals (sodium, potassium, calcium [Ca], magnesium, iron [Fe], copper, zinc [Zn], manganese [Mn], and cobalt) as well as toxic metals (cadmium [Cd], lead [Pb]) were determined in five tissues (liver, lung, kidney, muscle, and bone) of nestling rooks (Corvus frugilegus; 1 to 13 days old) found dead in seven breeding colonies in eastern Poland. Cd concentration in all analyzed tissues was in the narrow range of 17.0-17.2 mg/kg dry weight (dw) Cd, which in the light of the literature data indicates acute contamination by this toxic metal. Similarly, we found increased levels of Pb, which in all tissues ranged between 5.0 and 6.2 mg/kg dw. Results of multivariate general linear model (GLM) testing of the effect of three variables (tissue type, colony, and nestling age) on tissue concentrations of various metals showed significance for Fe, Cu, Zn, and Mn. Only concentrations of Ca, Fe, and Zn differed significantly between the analyzed tissues. GLM analysis did not show any statistically significant differences in tissue levels of minerals and both toxic metals among examined rookeries, which indicates the widespread presence of nonpoint Cd and Pb pollution linked to agricultural activity and similar levels of these inorganic contaminants on crop fields (feeding grounds) around breeding colonies. We concluded that high levels of both toxic metals, Cd and Pb, probably resulting from the diet of nestling rooks, are based mainly on a diet of ground-dwelling beetles gathered on crop fields. PMID:22945854

  4. Manganese and chronic hepatic encephalopathy

    Microsoft Academic Search

    D Krieger; S Krieger; L Theilmann; O Jansen; P Gass; H Lichtnecker

    1995-01-01

    SummaryClinical observations and animal studies have raised the hypothesis that increased concentrations of manganese (Mn) in whole blood might lead to accumulation of this metal within the basal ganglia in patients with end-stage liver disease. We studied ten patients with liver failure (and ten controls) by magnetic resonance imaging (MRI) and measurement of Mn in brain tissue of three patients

  5. Action of manganese on puberty

    E-print Network

    Lee, Bo Yeon

    2007-09-17

    to Mn than adults, we wanted to determine the effects of Mn exposure on puberty-related hormones and the onset of puberty, and discern the site and mechanism of Mn action. We demonstrated that the central administration of manganese chloride (MnCl2...

  6. Manganese Pollution and Violent Crime

    Microsoft Academic Search

    Roger D. Masters

    Evidence of my scientific career and qualification to assess harmful effects of pollution with manganese (or other toxins like lead or hydrofluorosilicic acid) is available in Who's Who in America. In addition to peer reviewed publications on the harmful effects of toxins. I have given papers at the International Society of Neurotoxicology, the American Academy of Environmental Medicine, & other

  7. Synthesis, characterization, optical and sensing property of manganese oxide nanoparticles

    SciTech Connect

    Manigandan, R.; Suresh, R.; Giribabu, K.; Narayanan, V., E-mail: vnnara@yahoo.co.in [Department of Inorganic Chemistry, University of Madras, Guindy Campus, Chennai 600 025 (India); Vijayalakshmi, L. [Annai Veilankanni's College for Women (Arts and Science), Saidapet, Chennai 600015 (India); Stephen, A. [Department of Nuclear Physics, University of Madras, Guindy Campus, Chennai 600 025 (India)

    2014-01-28

    Manganese oxide nanoparticles were prepared by thermal decomposition of manganese oxalate. Manganese oxalate was synthesized by reacting 1:1 mole ratio of manganese acetate and ammonium oxalate along with sodium dodecyl sulfate (SDS). The structural characterization of manganese oxalate and manganese oxide nanoparticles was analyzed by XRD. The XRD spectrum confirms the crystal structure of the manganese oxide and manganese oxalate. In addition, the average grain size, lattice parameter values were also calculated using XRD spectrum. Moreover, the diffraction peaks were broadened due to the smaller size of the particle. The band gap of manganese oxide was calculated from optical absorption, which was carried out by DRS UV-Visible spectroscopy. The morphology of manganese oxide nanoparticles was analyzed by SEM images. The FT-IR analysis confirms the formation of the manganese oxide from manganese oxalate nanoparticles. The electrochemical sensing behavior of manganese oxide nanoparticles were investigated using hydrogen peroxide by cyclic voltammetry.

  8. Synthesis, characterization, optical and sensing property of manganese oxide nanoparticles

    NASA Astrophysics Data System (ADS)

    Manigandan, R.; Suresh, R.; Giribabu, K.; Vijayalakshmi, L.; Stephen, A.; Narayanan, V.

    2014-01-01

    Manganese oxide nanoparticles were prepared by thermal decomposition of manganese oxalate. Manganese oxalate was synthesized by reacting 1:1 mole ratio of manganese acetate and ammonium oxalate along with sodium dodecyl sulfate (SDS). The structural characterization of manganese oxalate and manganese oxide nanoparticles was analyzed by XRD. The XRD spectrum confirms the crystal structure of the manganese oxide and manganese oxalate. In addition, the average grain size, lattice parameter values were also calculated using XRD spectrum. Moreover, the diffraction peaks were broadened due to the smaller size of the particle. The band gap of manganese oxide was calculated from optical absorption, which was carried out by DRS UV-Visible spectroscopy. The morphology of manganese oxide nanoparticles was analyzed by SEM images. The FT-IR analysis confirms the formation of the manganese oxide from manganese oxalate nanoparticles. The electrochemical sensing behavior of manganese oxide nanoparticles were investigated using hydrogen peroxide by cyclic voltammetry.

  9. Method of epitaxially depositing cadmium sulfide

    NASA Technical Reports Server (NTRS)

    Hawrylo, Frank Z. (Inventor)

    1980-01-01

    A single crystal layer of either cadmium sulfide or an alloy of cadmium sulfide and indium phosphide is epitaxially deposited on a substrate of cadmium sulfide by liquid phase epitaxy using indium as the solvent.

  10. Induction of reactivation of herpes simplex virus in murine sensory ganglia in vivo by cadmium.

    PubMed

    Fawl, R L; Roizman, B

    1993-12-01

    Herpes simplex viruses maintained in a latent state in sensory neurons in mice do not reactivate spontaneously, and therefore the factors or procedures which cause the virus to reactivate serve as a clue to the mechanisms by which the virus is maintained in a latent state. We report that cadmium sulfate induces latent virus to reactivate in 75 to 100% of mice tested. The following specific findings are reported. (i) The highest frequency of induction was observed after two to four daily administrations of 100 micrograms of cadmium sulfate. (ii) Zinc, copper, manganese, or nickel sulfate administered in equimolar amounts under the same regimen did not induce viral reactivation; however, zinc sulfate in molar ratios 25-fold greater than those of cadmium induced viral replication in 2 of 16 ganglia tested. (iii) Administration of zinc, nickel, or manganese prior to the cadmium sulfate reduced the incidence of ganglia containing infectious virus. (iv) Administration of cadmium daily during the first week after infection and at 2-day intervals to 13 days after infection resulted in the recovery from ganglia of infectious virus in titers 10- to 100-fold higher than those obtained from animals given saline. Moreover, infectious virus was recovered as late as 11 days after infection compared with 6 days in mice administered saline. (v) Administration of cadmium immediately after infection or repeatedly after establishment of latency did not exhaust the latent virus harbored by sensory neurons, inasmuch as the fraction of ganglia of mice administered cadmium and yielding infectious virus was similar to that observed in mice treated with saline. We conclude that induction of cadmium tolerance precludes reactivation of latent virus. If the induction of metallothionein genes was the sole factor required to cause reactivation of latent virus, it would have been expected that all metals which induce metallothioneins would also induce reactivation, which was not observed. The results therefore raise the possibility that in addition to inducing the metallothionein genes, cadmium inactivates the factors which maintain the virus in latent state. PMID:8230427

  11. Isolation of iron bacteria from terrestrial and aquatic environments

    NASA Astrophysics Data System (ADS)

    Schmidt, Bertram; Szewzyk, Ulrich

    2010-05-01

    Bacteria, which are capable of iron oxidation or at least iron deposition are widely distributed in environments where zones of dissolved ferrous iron and oxygen gradients are overlapping [1]. They take part in the biological cycling of iron and influence other cycles of elements for example carbon [2]. Manganese can be used for similar metabolic purposes as iron, because it can be biologically oxidized by chemolithotrophs or can be reduced by respirating bacteria as well [3, 4]. Bacterial activity is responsible for the accumulation of ferric iron compounds in their surroundings. The formation of bog ore is a well known example for a soil horizon, with an extreme enrichment of biogenic ferric iron [5]. We focused on the isolation of neutrophilic iron bacteria and bacteria capable of manganese oxidation. We used samples from Tierra del Fuego (Argentina) the National Park "Unteres Odertal" (Germany) and Berlin ground water wells. Microscopic examination of the samples revealed a considerable diversity of iron encrusted structures of bacterial origin. Most of these morphologic types are already well known. The taxonomic classification of many of these organisms is based on morphologic features and is not reliable compared to recent methods of molecular biology. That is mainly due to the fact, that most of these bacteria are hardly culturable or do not show their characteristic morphologic features under culture conditions. We established a collection of more than 300 iron depositing strains. Phylogenetic analyses showed that we have many yet uncultured strains in pure culture. We obtained many isolates which form distinct branches within long known iron bacteria groups like the Sphaerotilus-Leptothrix cluster. But some of the strains belong to groups, which have not yet been associated with iron oxidation activity. The strains deposit high amounts of oxidized iron and manganese compounds under laboratory conditions. However it is unclear if these precipitations are due to biological oxidation or biological deposition of chemically oxidized iron. We examined the morphologic characteristics of selected isolates under near-natural conditions to assign them to morphologic structures which occur in native samples. Our aim for the future is to describe several strains. References: [1] Weber, K. A. ; Achenbach, L. A. ; Coates, J. D. : Microorganisms pumping iron: anaerobic microbial iron oxidation and reduction. In: Nature Reviews Microbiology 4 (2006) 752-764 [2] Van Capellen, P. ; Wang Y. : Cycling of iron and manganese in surface sediments: a general theory for the coupled transport and reaction of carbon, oxygen, nitrogen, sulfur, iron and manganese. In: American Journal of Science 296 (1996) 197-243 [3] Tebo, B. M. ; Bargar, J. R. ; Clement, B. G. ; Dick, G. J. ; Murray, K. J. ; Parker, D. Verity R. ; Webb, S. M. : Biogenic manganese oxides: properties and mechanisms of formation. In: Annual Reviews Earth Planet Science 32 (2004) 287-328 [4] Erlich, H. L. : Manganese oxide reduction as a form of anaerobic respiration. In: Geomicrobiology Journal 5 (1987) 423-431 [5] Ghiorse W. C. : Biology of iron- and manganese-depositing bacteria. In: Annual Reviews 38 (1984) 515-550

  12. Chemical and microbiological studies of sulfide?mediated manganese reduction

    Microsoft Academic Search

    David J. Burdige; Kenneth H. Nealson

    1986-01-01

    Laboratory studies of manganese reduction by naturally occurring reduced inorganic compounds were undertaken, both to study further possible in situ mechanisms of manganese reduction and to examine how manganese redox reactions might be coupled to other biogeochemical processes. Chemical manganese reduction by sulfide (in the presence of excess manganese oxide) was found to be rapid and complete, with all sulfide

  13. Effects of manganese waste on growth, nodulation, proline levels, and enzymatic activities in Vigna unguiculata (L.) Walp

    Microsoft Academic Search

    Jayesh Panchal; N. C. Aery

    2008-01-01

    Phytoremediation studies were carried out on the waste of Kalakhunta manganese (Mn) mines located in Banswara, Rajasthan, which is rich in Mn and iron. Various treatments, including the addition of soil, farmyard manure, sawdust, and biogas slurry, as well as differing quantities of NPK and capping with 10% soil were undertaken to ameliorate the effects of inhospitable waste. The effect

  14. Alteration at translational but not transcriptional level of transferrin receptor expression following manganese exposure at the blood-CSF barrier in vitro

    SciTech Connect

    Li, G. Jane [School of Health Sciences, Purdue University, 550 Stadium Mall Drive, Room 1163D, West Lafayette, IN 47907 (United States); Zhao Qiuqu [School of Health Sciences, Purdue University, 550 Stadium Mall Drive, Room 1163D, West Lafayette, IN 47907 (United States); Zheng Wei [School of Health Sciences, Purdue University, 550 Stadium Mall Drive, Room 1163D, West Lafayette, IN 47907 (United States)]. E-mail: wzheng@purdue.edu

    2005-06-01

    Manganese exposure alters iron homeostasis in blood and cerebrospinal fluid (CSF), possibly by acting on iron transport mechanisms localized at the blood-brain barrier and/or blood-CSF barrier. This study was designed to test the hypothesis that manganese exposure may change the binding affinity of iron regulatory proteins (IRPs) to mRNAs encoding transferrin receptor (TfR), thereby influencing iron transport at the blood-CSF barrier. A primary culture of choroidal epithelial cells was adapted to grow on a permeable membrane sandwiched between two culture chambers to mimic blood-CSF barrier. Trace {sup 59}Fe was used to determine the transepithelial transport of iron. Following manganese treatment (100 {mu}M for 24 h), the initial flux rate constant (K {sub i}) of iron was increased by 34%, whereas the storage of iron in cells was reduced by 58%, as compared to controls. A gel shift assay demonstrated that manganese exposure increased the binding of IRP1 and IRP2 to the stem loop-containing mRNAs. Consequently, the cellular concentrations of TfR proteins were increased by 84% in comparison to controls. Assays utilizing RT-PCR, quantitative real-time reverse transcriptase-PCR, and nuclear run off techniques showed that manganese treatment did not affect the level of heterogeneous nuclear RNA (hnRNA) encoding TfR, nor did it affect the level of nascent TfR mRNA. However, manganese exposure resulted in a significantly increased level of TfR mRNA and reduced levels of ferritin mRNA. Taken together, these results suggest that manganese exposure increases iron transport at the blood-CSF barrier; the effect is likely due to manganese action on translational events relevant to the production of TfR, but not due to its action on transcriptional, gene expression of TfR. The disrupted protein-TfR mRNA interaction in the choroidal epithelial cells may explain the toxicity of manganese at the blood-CSF barrier.

  15. Hypercalciuria related to cadmium exposure.

    PubMed

    Scott, R; Patterson, P J; Burns, R; Ottoway, J M; Hussain, F E; Fell, G S; Dumbuya, S; Iqbal, M

    1978-05-01

    A work force has been investigated for possible cadmium intoxication. One group who are coppersmiths have an 18.5 per cent prevalence of upper urinary tract stone disease associated with a statistically highly significant hypercalciuria and reduced serum inorganic phosphate. Proof of exposure to cadmium has been confirmed in all workers. The trace element cadmium should be kept in mind when investigating stone formers who exhibit an unexplained hypercalciuria. PMID:209595

  16. Filling Narrow Trenches by Iodine-Catalyzed CVD of Copper and Manganese on Manganese Nitride Barrier/Adhesion Layers

    E-print Network

    Filling Narrow Trenches by Iodine-Catalyzed CVD of Copper and Manganese on Manganese Nitride). Conformally deposited manganese nitride serves as an underlayer that initially chemisorbs iodine. CVD of copper or copper-manganese alloy releases the adsorbed iodine atoms from the surface of the manganese

  17. Cadmium biosorption by Saccharomyces cerevisiae

    SciTech Connect

    Volesky, B.; May, H.; Holan, Z.R. (McGill Univ., Montreal, Quebec (Canada))

    1993-04-01

    Cadmium uptake by nonliving and resting cells of Saccharomyces cerevisiae obtained from aerobic or anaerobic cultures from pure cadmium-bearing solutions was examined. The highest cadmium uptake exceeding 70 mg Cd/g was observed with aerobic baker's yeast biomass from the exponential growth phase. Nearly linear sorption isotherms featured by higher sorbing resting cells together with metal deposits localized exclusively in vacuoles indicate the possibility of a different metal-sequestering mechanism when compared to dry nonliving yeasts which did not usually accumulate more than 20 mg Cd/g. The uptake of cadmium was relatively fast, 75% of the sorption completed in less than 5 min.

  18. Renal cadmium overload without nephrotoxicity.

    PubMed Central

    Ghose, R R; Morgan, W D; Cummins, P E

    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 saturation with cadmium. PMID:7236544

  19. Nickel-cadmium cells

    NASA Technical Reports Server (NTRS)

    Rubin, E. J.; Turchan, M. J.

    1974-01-01

    A high energy density nickel cadmium cell of aerospace quality was designed. The approach used was to utilize manufacturing techniques which produce highly uniform and controlled starting materials in addition to improvements in the overall design. Parameters controlling the production of plaque and both positive and negative plate were studied. Quantities of these materials were produced and prototype cells were assembled to test the proposed design.

  20. Dioxanates of Cadmium Chloride

    Microsoft Academic Search

    Martin G. Chasanov; Cecil C. Lynch

    1957-01-01

    DIOXANATES of cadmium chloride were precipitated from a solution of the anhydrous salts (certified purity) in acetal-free dioxane, prepared from Eastman Kodak technical 1,4-dioxane by the method of Eigenberger1. The crude dioxanate (that is, wet with dioxane) was placed in the bulb of the isotenoscope of Smith and Menzies2, and oil of paraffin, U.S.P., was employed as the levelling liquid.

  1. Blood and urine cadmium and bioelements profile in nickel-cadmium battery workers in Serbia.

    PubMed

    Bulat, Z Plamenac; Dukic-Cosic, D; Dokic, M; Bulat, P; Matovic, V

    2009-03-01

    Although cadmium (Cd) is extensively used for nickel-cadmium battery production, few recent reports are available on the effect of this toxic metal on the imbalance of biometals in occupational exposure. The current study was carried out to determine the Cd level and its effect on the content of bioelements: zinc, cooper, magnesium, and iron in blood and urine of workers exposed to Cd during nickel-cadmium battery production. beta(2)-microglobulins (beta(2)-MG), as indicators of kidney damage, were determined in urine.The study group comprised 32 male nickel-cadmium battery workers, and the control group had 15 male construction workers with no history of Cd exposure. Levels of Cd and bioelements were determined in blood and urine by atomic absorption spectrophotometry.Cd concentration in blood of exposed workers was around 10 microg/L and in urine ranged from 1.93 to 8.76 microg/g creatinine (cr). Urine Cd concentration was significantly higher in exposed workers than in the controls, although no statistical difference in beta(2)-MG content was observed in urine between the two groups. Blood Zn and Mg level were significantly reduced and urine Zn level was increased in Cd-exposed group when compared with controls.The mean Cd concentrations in blood and urine did not exceed the recommended reference values of 10 microg/L in blood and 10 microg/g cr in urine. Cd exposure resulted in disturbances of Zn in blood and urine and Mg in blood but had no effect on Cu and Fe content in biological fluids. PMID:19458135

  2. Photodisintegration of cadmium isotopes

    NASA Astrophysics Data System (ADS)

    Belyshev, S. S.; Ishkhanov, B. S.; Kuznetsov, A. A.; Orlin, V. N.; Stopani, K. A.; Khankin, V. V.; Shvedunov, N. V.

    2014-07-01

    The yields of photonucleon reactions having various multiplicities and occurring on a natural mixture of cadmium isotopes were measured. Bremsstrahlung whose spectrum had an endpoint energy of 55 MeV was used as a gamma-ray source. The reaction yields were determined with the aid of the induced-activity method. The yields of photonuclear reactions for several channels of decay of excited states of cadmium isotopes in the energy region extending up to 55MeV were obtained for the first time. A comparison of the results obtained experimentallywith the results of theoretical calculations reveals that, in the case of heavy cadmium isotopes, it is possible to obtain a reasonably good description of experimental data. In the case of the light isotope 106Cd, however, the results of the theoretical calculations are at odds with experimental data, and this is likely to be due to special features of the shell structure of the isotope 106Cd, which lies near the beta-stability boundary.

  3. Current status of cadmium as an environmental health problem

    SciTech Connect

    Jaerup, Lars [Department of Epidemiology and Public Health, Imperial College London (United Kingdom); Institute of Environmental Medicine, Karolinska Institutet, Stockholm (Sweden)], E-mail: l.jarup@imperial.ac.uk; Akesson, Agneta [Institute of Environmental Medicine, Karolinska Institutet, Stockholm (Sweden)

    2009-08-01

    Cadmium is a toxic metal occurring in the environment naturally and as a pollutant emanating from industrial and agricultural sources. Food is the main source of cadmium intake in the non-smoking population. The bioavailability, retention and toxicity are affected by several factors including nutritional status such as low iron status. Cadmium is efficiently retained in the kidney (half-time 10-30 years) and the concentration is proportional to that in urine (U-Cd). Cadmium is nephrotoxic, initially causing kidney tubular damage. Cadmium can also cause bone damage, either via a direct effect on bone tissue or indirectly as a result of renal dysfunction. After prolonged and/or high exposure the tubular injury may progress to glomerular damage with decreased glomerular filtration rate, and eventually to renal failure. Furthermore, recent data also suggest increased cancer risks and increased mortality in environmentally exposed populations. Dose-response assessment using a variety of early markers of kidney damage has identified U-Cd points of departure for early kidney effects between 0.5 and 3 {mu}g Cd/g creatinine, similar to the points of departure for effects on bone. It can be anticipated that a considerable proportion of the non-smoking adult population has urinary cadmium concentrations of 0.5 {mu}g/g creatinine or higher in non-exposed areas. For smokers this proportion is considerably higher. This implies no margin of safety between the point of departure and the exposure levels in the general population. Therefore, measures should be put in place to reduce exposure to a minimum, and the tolerably daily intake should be set in accordance with recent findings.

  4. Current status of cadmium as an environmental health problem.

    PubMed

    Järup, Lars; Akesson, Agneta

    2009-08-01

    Cadmium is a toxic metal occurring in the environment naturally and as a pollutant emanating from industrial and agricultural sources. Food is the main source of cadmium intake in the non-smoking population. The bioavailability, retention and toxicity are affected by several factors including nutritional status such as low iron status. Cadmium is efficiently retained in the kidney (half-time 10-30 years) and the concentration is proportional to that in urine (U-Cd). Cadmium is nephrotoxic, initially causing kidney tubular damage. Cadmium can also cause bone damage, either via a direct effect on bone tissue or indirectly as a result of renal dysfunction. After prolonged and/or high exposure the tubular injury may progress to glomerular damage with decreased glomerular filtration rate, and eventually to renal failure. Furthermore, recent data also suggest increased cancer risks and increased mortality in environmentally exposed populations. Dose-response assessment using a variety of early markers of kidney damage has identified U-Cd points of departure for early kidney effects between 0.5 and 3 microg Cd/g creatinine, similar to the points of departure for effects on bone. It can be anticipated that a considerable proportion of the non-smoking adult population has urinary cadmium concentrations of 0.5 microg/g creatinine or higher in non-exposed areas. For smokers this proportion is considerably higher. This implies no margin of safety between the point of departure and the exposure levels in the general population. Therefore, measures should be put in place to reduce exposure to a minimum, and the tolerably daily intake should be set in accordance with recent findings. PMID:19409405

  5. Structure and magnetic properties of manganese-zinc-ferrites prepared by spray pyrolysis method

    NASA Astrophysics Data System (ADS)

    Kotsikau, Dzmitry; Ivanovskaya, Maria; Pankov, Vladimir; Fedotova, Yulia

    2015-01-01

    A spray pyrolysis of a water solution of iron, manganese and iron nitrates is applied to prepare Zn0.5Mn0.5Fe2O4 single-phase ferrite with a spinel-type structure. The samples are characterized by means of differential scanning calorimetry, scanning and transmission electron microscopy, X-ray diffraction, infrared and 57Fe Mössbauer spectroscopy. The mass magnetization ? and the magnetic susceptibility 1/? of the ferrites are measured as a function of temperature over the range of 78-728 K. The obtained sample contains nanoparticles with an average diameter d ?7 nm possessing MnxZnyFe3-(x+y)O4 spinel-type structure with a uniform distribution of manganese and zinc atoms over the ferrite lattice. The Curie temperature is determined to be 375 ÷ 380 K.

  6. 40 CFR 721.10003 - Manganese heterocyclic tetraamine complex (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Manganese heterocyclic tetraamine complex (generic...Chemical Substances § 721.10003 Manganese heterocyclic tetraamine complex (generic...chemical substances identified generically as manganese heterocyclic tetraamine...

  7. 40 CFR 721.10003 - Manganese heterocyclic tetraamine complex (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Manganese heterocyclic tetraamine complex (generic...Chemical Substances § 721.10003 Manganese heterocyclic tetraamine complex (generic...chemical substances identified generically as manganese heterocyclic tetraamine...

  8. 40 CFR 721.10011 - Barium calcium manganese strontium oxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Barium calcium manganese strontium oxide. 721.10011 Section...Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance...substance identified as barium calcium manganese strontium oxide (PMN...

  9. 40 CFR 721.10011 - Barium calcium manganese strontium oxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Barium calcium manganese strontium oxide. 721.10011 Section...Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance...substance identified as barium calcium manganese strontium oxide (PMN...

  10. 40 CFR 721.10003 - Manganese heterocyclic tetraamine complex (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Manganese heterocyclic tetraamine complex (generic...Chemical Substances § 721.10003 Manganese heterocyclic tetraamine complex (generic...chemical substances identified generically as manganese heterocyclic tetraamine...

  11. 40 CFR 721.10003 - Manganese heterocyclic tetraamine complex (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Manganese heterocyclic tetraamine complex (generic...Chemical Substances § 721.10003 Manganese heterocyclic tetraamine complex (generic...chemical substances identified generically as manganese heterocyclic tetraamine...

  12. 40 CFR 721.10011 - Barium calcium manganese strontium oxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Barium calcium manganese strontium oxide. 721.10011 Section...Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance...substance identified as barium calcium manganese strontium oxide (PMN...

  13. 40 CFR 721.10011 - Barium calcium manganese strontium oxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Barium calcium manganese strontium oxide. 721.10011 Section...Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance...substance identified as barium calcium manganese strontium oxide (PMN...

  14. 40 CFR 721.10003 - Manganese heterocyclic tetraamine complex (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Manganese heterocyclic tetraamine complex (generic...Chemical Substances § 721.10003 Manganese heterocyclic tetraamine complex (generic...chemical substances identified generically as manganese heterocyclic tetraamine...

  15. 40 CFR 721.10201 - Cobalt lithium manganese nickel oxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...false Cobalt lithium manganese nickel oxide. 721.10201 Section...10201 Cobalt lithium manganese nickel oxide. (a) Chemical substance...as cobalt lithium manganese nickel oxide (PMN P-04-269...Requirements as specified in § 721.63 (a)(1),...

  16. 40 CFR 721.10201 - Cobalt lithium manganese nickel oxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...false Cobalt lithium manganese nickel oxide. 721.10201 Section...10201 Cobalt lithium manganese nickel oxide. (a) Chemical substance...as cobalt lithium manganese nickel oxide (PMN P-04-269...Requirements as specified in § 721.63 (a)(1),...

  17. 40 CFR 721.10201 - Cobalt lithium manganese nickel oxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...false Cobalt lithium manganese nickel oxide. 721.10201 Section...10201 Cobalt lithium manganese nickel oxide. (a) Chemical substance...as cobalt lithium manganese nickel oxide (PMN P-04-269...Requirements as specified in § 721.63 (a)(1),...

  18. 40 CFR 721.10011 - Barium calcium manganese strontium oxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Barium calcium manganese strontium oxide. 721.10011...Chemical Substances § 721.10011 Barium calcium manganese strontium oxide. (a...chemical substance identified as barium calcium manganese strontium oxide (PMN...

  19. Removal of cadmium by combining deferasirox and desferrioxamine chelators in rats.

    PubMed

    Fatemi, S Jamilaldine; Saljooghi, Amir Shokooh; Balooch, Faezeh Dahooee; Iranmanesh, Marzieh; Golbafan, Mohammad Reza

    2012-02-01

    An investigation was conducted to evaluate the ability of two chelators, deferasirox and desferrioxamine (DFO), in removing cadmium from biological system. The potential efficiency of those chelators were investigated after cadmium administration for 60 days following two dose levels of 20 and 40 mg/kg body weight daily to male rats. However, abnormalities were observed in clinical signs after cadmium administration, such as yellowish discoloration of hair, flaccid and hypotonic muscles, irritability, weakness and loss of weight. The hypothesis that the two chelators might be more efficient as combined therapy than single therapy in removing metal ions from the body was considered. In this way, two known chelators, deferasirox and DFO were chosen and tested in the acute rat model. The chelation therapy results show that deferasirox and DFO are able (?)to remove cadmium ions from the body, while iron concentration returned to the normal level and symptoms are decreased. PMID:22134990

  20. Negative impact of manganese on honeybee foraging.

    PubMed

    Søvik, Eirik; Perry, Clint J; LaMora, Angie; Barron, Andrew B; Ben-Shahar, Yehuda

    2015-03-01

    Anthropogenic accumulation of metals such as manganese is a well-established health risk factor for vertebrates. By contrast, the long-term impact of these contaminants on invertebrates is mostly unknown. Here, we demonstrate that manganese ingestion alters brain biogenic amine levels in honeybees and fruit flies. Furthermore, we show that manganese exposure negatively affects foraging behaviour in the honeybee, an economically important pollinator. Our findings indicate that in addition to its direct impact on human health, the common industrial contaminant manganese might also have indirect environmental and economical impacts via the modulation of neuronal and behavioural functions in economically important insects. PMID:25808001

  1. Adsorptive removal of cadmium by natural red earth: equilibrium and kinetic studies

    Microsoft Academic Search

    Kushani Mahatantila; Meththika Vithanage; Yasushi Seike; Minoru Okumura

    2012-01-01

    Natural red earth (NRE), an iron-coated sand found in the north western part of Sri Lanka, was used to examine the retention behaviour of cadmium, a heavy metal postulated as a factor of chronic kidney disease in Sri Lanka. Adsorption studies were conducted as a function of pH, ionic strength, initial Cd loading and time. The Cd adsorption increased from

  2. Adsorptive removal of cadmium by natural red earth: equilibrium and kinetic studies

    Microsoft Academic Search

    Kushani Mahatantila; Meththika Vithanage; Yasushi Seike; Minoru Okumura

    2011-01-01

    Natural red earth (NRE), an iron-coated sand found in the north western part of Sri Lanka, was used to examine the retention behaviour of cadmium, a heavy metal postulated as a factor of chronic kidney disease in Sri Lanka. Adsorption studies were conducted as a function of pH, ionic strength, initial Cd loading and time. The Cd adsorption increased from

  3. High copper concentrations in squid livers in association with elevated levels of silver, cadmium, and zinc

    Microsoft Academic Search

    J. H. Martin; A. R. Flegal

    1975-01-01

    Livers from 43 Loligo opalescens, 14 Ommastrephes bartrami, and 7 Symplectoteuthis oualaniensis were analyzed for their silver, cadmium, copper, zinc and iron contents. Copper concentrations of up to 15,000 µg\\/g dry weight were found in L. opalescens in conjunction with significant correlations between this element and Ag, Cd and Zn. The latter elements are known to affect Cu metabolism in

  4. Effect of dietary calcium on cadmium absorption and retention in suckling rats.

    PubMed

    Sari?, Marijana Matek; Blanusa, Maja; Piasek, Martina; Varnai, Veda Marija; Juresa, Dijana; Kostial, Krista

    2002-06-01

    The effect of calcium supplementation on absorption and retention of cadmium in the suckling period was evaluated in Wistar rat pups of both sexes. Animals were maintained in the litters with the mother rats and supplemented with 1%, 3% or 6% calcium (as CaHPO4 x 2H2O) in cow's milk by artificial feeding from day of birth 6 through 14. All rats were exposed to cadmium (as CdCl2 x H2O) either orally or parenterally. Oral cadmium dose of 0.5 mg/kg body weight a day was administered through nine-day period of calcium supplementation and parenteral cadmium dose was injected subcutaneously in a single dose of 0.5 mg Cd/kg body weight prior to calcium supplementation. On experimental day 10 (at the age of pups of 15 days) all animals were killed and the liver, kidneys, brain and carcass (body without organs and skin) were removed for element analyses. Cadmium and essential elements calcium, zinc and iron were analysed in the tissues by atomic absorption spectrometry. Results showed that after oral exposure cadmium concentrations in all calcium-supplemented groups were significantly decreased in the organs and carcass and that the effect was dose-related. No such effect of calcium was found after parenteral cadmium exposure. Calcium supplementation per se significantly increased calcium concentration in the carcass and had no effect on iron in organs and zinc in carcass. It was concluded that calcium supplementation during the suckling period could be an efficient way of reducing oral cadmium absorption and retention without affecting tissue essential trace element concentrations. PMID:12046926

  5. Interactions of bacteria with cadmium

    Microsoft Academic Search

    Eliora Z. Ron; Dror Minz; N. P. Finkelstein; Eugene Rosenberg

    1992-01-01

    Cadmium pollution arises mainly from contamination of minerals used in agriculture and from industrial processes. The usual situation is of large volumes of soil and water that are contaminated with low — but significant — concentrations of cadmium. Therefore, detoxification of the polluted water and soil involves the concentration of the metal, or binding it in a way that makes

  6. Cadmium Toxicity in Glutathione Mutants of Escherichia coli? †

    PubMed Central

    Helbig, Kerstin; Grosse, Cornelia; Nies, Dietrich H.

    2008-01-01

    The higher affinity of Cd2+ for sulfur compounds than for nitrogen and oxygen led to the theoretical consideration that cadmium toxicity should result mainly from the binding of Cd2+ to sulfide, thiol groups, and sulfur-rich complex compounds rather than from Cd2+ replacement of transition-metal cations from nitrogen- or oxygen-rich biological compounds. This hypothesis was tested by using Escherichia coli for a global transcriptome analysis of cells synthesizing glutathione (GSH; wild type), ?-glutamylcysteine (?gshB mutant), or neither of the two cellular thiols (?gshA mutant). The resulting data, some of which were validated by quantitative reverse transcription-PCR, were sorted using the KEGG (Kyoto Encyclopedia of Genes and Genomes) orthology system, which groups genes hierarchically with respect to the cellular functions of their respective products. The main difference among the three strains concerned tryptophan biosynthesis, which was up-regulated in wild-type cells upon cadmium shock and strongly up-regulated in ?gshA cells but repressed in ?gshB cells containing ?-glutamylcysteine instead of GSH. Overall, however, all three E. coli strains responded to cadmium shock similarly, with the up-regulation of genes involved in protein, disulfide bond, and oxidative damage repair; cysteine and iron-sulfur cluster biosynthesis; the production of proteins containing sensitive iron-sulfur clusters; the storage of iron; and the detoxification of Cd2+ by efflux. General energy conservation pathways and iron uptake were down-regulated. These findings indicated that the toxic action of Cd2+ indeed results from the binding of the metal cation to sulfur, lending support to the hypothesis tested. PMID:18539742

  7. Single crystal EPR studies on Mn(II)-doped sarcosine cadmium chloride and sarcosine cadmium bromide: study of zero-field splitting tensor in iso-structural complexes.

    PubMed

    Pathinettam, Padiyan D; Muthukrishnan, C; Murugesan, R

    2002-02-01

    EPR spectra of single crystals of Mn(II)-doped sarcosine cadmium chloride and sarcosine cadmium bromide are studied in Q-band and in X-band at room temperature. Two magnetically inequivalent sites are observed in both the lattices in a distorted octahedral environment. The spin-Hamiltonian parameters are extracted and are found to have a rhombic symmetry. The angular variation of the zero-field transitions is simulated for one of the sites with an asymmetric zero-field tensor D = 480 x 10(-4) cm(-1), E = -115 x 10(-4) cm(-1) and a = 10 x 10(-4) cm(-1) for Mn(II) in sarcosine cadmium chloride and with D = 460 x 10(-4) cm(-1) E = -98 x 10(-4) cm(-1) and a = 10 x 10(-4) cm(-1) for Mn(II) in sarcosine cadmium bromide. The observed large value of zero-field tensor is due to the steric effects of the crystal packing caused by the ligands. Matumura's plot predicts an average covalency of 8.8 and 7.7% for the manganese-ligand bond in SCC and SCB lattices respectively. PMID:11905536

  8. Oxidation of antimony (III) by amorphous iron and manganese oxyhydroxides

    Microsoft Academic Search

    Nelson Belzile; Yu-Wei Chen; Zijian Wang

    2001-01-01

    Amorphous forms of natural and synthetic Fe oxyhydroxides and synthetic Mn oxyhydroxides were used to study the oxidation of antimonite, Sb(III), at different pH values. Sb species were measured by differential pulse adsorptive stripping voltametry (DPACSV). The oxidation of Sb(III) to Sb(V) was always rapid and completed after a few days following pseudo-first order rate laws. A slightly slower oxidation

  9. Interstellar iron and manganese - UV oscillator strengths and abundances

    NASA Technical Reports Server (NTRS)

    Lugger, P.; Barker, E.; York, D. G.; Oegerle, W.

    1982-01-01

    Observations of 16 UV resonance lines of Fe II and six of Mn II in five stars are used to derive new f-values for the lines of these species at wavelengths lower than 1300 A. Values of forbidden lines Fe/H and Mn/H are derived. These new values are used to reassess mean depletions and range of variations in depletions for several lines of sight. On an integrated line-of-sight basis, depletions of Fe and Mn show larger variations than P, Cl, or Zn. The mean local depletion forbidden line Fe/H is 1.65, in interstellar gas. One Fe II line, 2366.864 A, has never been detected. Its f-value is shown to be much lower than previously thought. This line is therefore not useful for interstellar studies at the present time. It is suggested that the true wavelength of 1142 A of Fe II, from UV multiplet 10, is 1142.285 A.

  10. Manganese inhibition of microbial iron reduction in anaerobic sediments

    Microsoft Academic Search

    Derek R. Lovley; Elizabeth J. P. Phillips

    1988-01-01

    Potential mechanisms for the lack of Fe(II) accumulation in Mn(IV)?con?taining anaerobic sediments were investigated. The addition of Mn(IV) to sediments in which Fe(III) reduction was the terminal electron?accepting process removed all the pore?water Fe(II), completely inhibited net Fe(III) reduction, and stimulated Mn(IV) reduction. In a solution buffered at pH 7, Mn(IV) oxidized Fe(II) to amorphic Fe(III) oxide. Mn(IV) naturally present

  11. Microbial reduction of manganese oxides - Interactions with iron and sulfur

    NASA Technical Reports Server (NTRS)

    Myers, Charles R.; Nealson, Kenneth H.

    1988-01-01

    Alteromonas putrefaciens (strain MR-1) is capable of rapid Mn(IV) reduction under conditions of neutral pH and temperatures characteristic of the Oneida Lake, New York, sediments from which it was isolated. MR-1 also reduces Fe(3+) to Fe(2+), and disproportionates thiosulfate to sulfide and sulfite; independently, the Fe(2+) and sulfide act as rapid reductants of Mn. The addition of Fe(3+) or thiosulfate to cultures of MR-1 in the presence of oxidized Mn increases the rate and the extent of Mn reduction relative to that observed in the absence of Fe(3+) or thiosulfate. Furthermore, when Fe(3+) and Mn oxides are present conjointly, Fe(2+) does not appear until the reduction of the oxidized Mn is complete. These results demonstrate that the observed rates of Fe(2+) and sulfide production may underestimate the total rates of Fe and sulfate reduction in those environments containing oxidized Mn. These results also demonstrate the potential impact that a single microbe can exert on sediment geochemistry, and provide the basis for preliminary models of the complexity of microbial and geochemical interactions that occur.

  12. Hydrogenation of carbon monoxide over Raney iron-manganese catalysts

    Microsoft Academic Search

    1983-01-01

    The Raney Fe and Raney Fe-Mn catalysts were prepared by leaching the aluminum from Al-Fe (50\\/50 wt%) and Al-Fe-Mn (59\\/38\\/3 wt%) alloys with an aqueous solution of sodium hydroxide (2 to 20 wt%) in the temperature range of 298 to 363 K by two different leaching modes, caustic or alloy addition. The major phase in all the Raney Fe and

  13. Solubilization of plutonium hydrous oxide by iron-reducing bacteria

    Microsoft Academic Search

    Patricia A. Rusin; Leticia Quintana; James R. Brainard; B. A. Strietelmeler; C. Drew Tait; Scott A. Ekberg; Phillip D. Palmer; Thomas W. Newton; David L. Clark

    1994-01-01

    The removal of plutonium from soils id challenging because of its strong sorption to soils and limited solubility, Microbial reduction of metals is known to affect the speciation and solubility of sparingly soluble metals in the environment, notably iron and manganese. The similarity in reduction potential for [alpha]-FeOOH(s) and hydrous PuO[sub 2](s) suggests that iron-reducing bacteria may also reduce and

  14. Manganese and Oxidative Damage in Cucumber

    Microsoft Academic Search

    Rajeev Gopal

    2008-01-01

    Micronutrients in low or high concentration can affect growth, respiration, photosynthesis, and reproduction in plants. Cucumber (Cucumis sativus, L.) is grown in India in areas low or high in manganese concentration in soils. A study was conducted to investigate the effects of manganese concentration on some metabolic activities affecting developmental responses in cucumber. Seed of cucumber, cv. Sonali, were grown

  15. Manganese regulates expression of manganese peroxide by Phanerochaete chrysosporium

    SciTech Connect

    Brown, J.A.; Glenn, J.K.; Gold, M.H. (Oregon Graduate Institute of Science and Technology, Beaverton (USA))

    1990-06-01

    The appearance of manganese peroxidase (MnP) activity in nitrogen-limited cultures of Phanerochaete chrysosporium is dependent on the presence of manganese. Cultures grown in the absence of Mn developed normally and produced normal levels of the secondary metabolite veratryl alcohol but produced no MnP activity. Immunoblot analysis indicated that appearance of MnP protein in the extracellular medium was also dependent on the presence of Mn. Intracellular MnP protein was detectable only in cells grown in the presence of Mn. MnP mRNA was detected by Northern (RNA) blot analysis only in cells grown in the presence of Mn. If Mn was added to 4-day-old nitrogen-limited Mn-deficient cultures, extracellular MnP activity appeared after 6 h and reached a maximum after 18 h. Both actinomycin D and cycloheximide inhibited the induction of MnP activity by Mn. These results indicate that Mn, the substrate of the enzyme, is involved in the transcriptional regulation of the MnP gene.

  16. Dinuclear manganese centers in the manganese-lead-tellurate glasses.

    PubMed

    Rada, S; Dehelean, A; Culea, M; Culea, E

    2011-07-01

    FTIR, UV-VIS and EPR spectra of manganese doped lead-tellurate glasses with composition xMnO·(100-x)[4TeO2·PbO2] where x=0, 1, 5, 10, 20, 30, 40mol% have been studied. The FTIR spectra show the formation of the Mn-O-Pb and Mn-O-Te bridging bonds by increasing of MnO concentration. The UV-VIS spectra show the Mn(+3) species exhibit pronounced absorption, which masks the Mn(+2) spin-forbidden absorption bands when Mn(+2) ions are in high concentrations in these glasses. The EPR spectra exhibit resonance signals characteristic of Mn(+2) ions. The resonance signal located at g?2 is due to Mn(+2) ions in an environment close to octahedral symmetry, whereas the resonance at g?4.3 and 3.3 are attributed to the rhombic surroundings of the Mn(+2) ions. The increase in the MnO content gives rise to absorption at g?2.4 and the paramagnetic ions are involved in dinuclear manganese centers. PMID:21498108

  17. Manganese borohydride; synthesis and characterization.

    PubMed

    Richter, Bo; Ravnsbæk, Dorthe B; Tumanov, Nikolay; Filinchuk, Yaroslav; Jensen, Torben R

    2015-02-17

    Solvent-based synthesis and characterization of ?-Mn(BH4)2 and a new nanoporous polymorph of manganese borohydride, ?-Mn(BH4)2, via a new solvate precursor, Mn(BH4)2·1/2S(CH3)2, is presented. Manganese chloride is reacted with lithium borohydride in a toluene/dimethylsulfide mixture at room temperature, which yields halide and solvent-free manganese borohydride after extraction with dimethylsulfide (DMS) and subsequent removal of residual solvent. This work constitutes the first example of establishing a successful, reproducible solvent-based synthesis route for a pure, crystalline, stable transition metal borohydride. The new polymorph, ?-Mn(BH4)2, is shown to be the manganese counterpart of the zeolite-like compound, ?-Mg(BH4)2 (cubic, a = 16.209(1) Å, space group Id3[combining macron]a). It is verified that large pores (diameter > 6.0 Å) exist in this structure. The solvate, Mn(BH4)2·1/2S(CH3)2, is subsequently shown to be the analogue of Mg(BH4)2·1/2S(CH3)2. As the structural analogies between Mg(BH4)2 and Mn(BH4)2 became evident a new polymorph of Mg(BH4)2 was identified and termed ?-Mg(BH4)2. ?-Mg(BH4)2 is the structural counterpart of ?-Mn(BH4)2. All synthesis products are characterized employing synchrotron radiation-powder X-ray diffraction, infrared spectroscopy and thermogravimetric analysis in combination with mass spectroscopy. Thermal analysis reveals the decomposition of Mn(BH4)2 to occur at 160 °C, accompanied by a mass loss of 14.8 wt%. A small quantity of the desorbed gaseous species is identified as diborane (?m(Mn(BH4)2) = 9.5 wt% H2), while the remaining majority is found to be hydrogen. PMID:25611294

  18. Manganese Transport via the Transferrin Mechanism

    PubMed Central

    Gunter, Thomas E.; Gerstner, Brent; Gunter, Karlene K.; Malecki, Jon; Gelein, Robert; Valentine, William M.; Aschner, Michael; Yule, David I.

    2013-01-01

    Excessive manganese (Mn) uptake by brain cells, particularly in regions like the basal ganglia, can lead to toxicity. Mn2+ is transported into cells via a number of mechanisms, while Mn3+ is believed to be transported similarly to iron (Fe) via the transferrin (Tf) mechanism. Cellular Mn uptake is therefore determined by the activity of the mechanisms transporting Mn into each type of cell and by the amounts of Mn2+, Mn3+ and their complexes to which these cells are exposed; this complicates understanding the contributions of each transporter to Mn toxicity. While uptake of Fe3+ via the Tf mechanism is well understood, uptake of Mn3+ via this mechanism has not been systematically studied. The stability of the Mn3+Tf complex allowed us to form and purify this complex and label it with a fluorescent (Alexa green) tag. Using purified and labeled Mn3+Tf and biophysical tools, we have developed a novel approach to study Mn3+Tf transport independently of other Mn transport mechanisms. This approach was used to compare the uptake of Mn3+Tf into neuronal cell lines with published descriptions of Fe3+ uptake via the Tf mechanism, and to obtain quantitative information on Mn uptake via the Tf mechanism. Results confirm that in these cell lines significant Mn3+ is transported by the Tf mechanism similarly to Fe3+Tf transport; although Mn3+Tf transport is markedly slower than other Mn transport mechanisms. This novel approach may prove useful for studying Mn toxicity in other systems and cell types. PMID:23146871

  19. Use of Iron and Manganese-Oxidizing Bacteria for the Combined Removal of Iron, Manganese and Arsenic from Contaminated Groundwater

    Microsoft Academic Search

    Ioannis A. Katsoyiannis; Anastasios I. Zouboulis

    2006-01-01

    The problem of groundwater contamination with arsenic has been under extensive discussion, especially in recent years, because of its adverse effects on human health and its widespread presence in groundwater throughout the world. Large drinking water plants in developed countries normally find alternative and arsenic-free water resources, or they apply con- ventional arsenic removal methods, such as coagulation\\/filtration, activated alumina

  20. Divalent metal transporter 1 in lead and cadmium transport.

    PubMed

    Bressler, Joseph P; Olivi, Luisa; Cheong, Jae Hoon; Kim, Yongbae; Bannona, Desmond

    2004-03-01

    The effect of exposure to cadmium (Cd) and lead (Pb) on human health has been recognized for many years and recent information suggests that minimal exposure levels are themselves too high. Common scenarios for Pb exposure include occupational, residential, and/or behavioral (hand-to-mouth activity) settings. The main source of Cd exposure for nonsmokers is dietary, through plants or animals that accumulate the metal. Specific cellular importers for Pb and Cd are unlikely as these metals are nonessential and toxic. Accordingly, in the intestine, the operational mechanism is assumed to be inadvertent uptake through pathways intended for essential nutrients such as iron. Results from experimental and epidemiological studies indicated that diets low in iron (Fe) result in increased absorption of Pb and Cd, suggesting common molecular mechanisms of Cd and Pb transport. Indeed, recent mechanistic studies found that the intestinal transporter for nonheme iron, divalent metal transporter 1 (DMT1), mediates the transport of Pb and Cd. DMT1 is regulated, in part, by dietary iron, and chemical species of Cd and Pb that are transported by DMT1 would be made available through digestion and are also found in plasma. Accordingly, the involvement of DMT1 in metal uptake offers a mechanistic explanation for why an iron-deficient diet is a risk factor for Pb and Cd poisoning. It also suggests that diets rich in iron-containing food could be protective against heavy metal poisoning. PMID:15105261

  1. Cadmium and mercury nephrotoxicity

    NASA Astrophysics Data System (ADS)

    Nicholson, J. K.

    1983-08-01

    Despite increasing attempts to control environmental pollution, changes in the distribution and bioavailability of toxic metals like mercury and cadmium are still occurring. Apart from natural processes, other contributory factors include the gradual spread of industrialization, the use of sewage sludge as a fertilizer and the acidification of Northern Hemisphere ground-water. Animals (including man and domestic varieties) can accumulate harmful concentrations of toxic metals1-5. We therefore looked for damage to the kidneys in seabirds contaminated with mercury and cadmium and made comparisons with kidneys from three other groups of animals: seabirds from an uncontaminated colony, metal-dosed birds and metal-dosed mice. We report here that, comparing all these groups of animals, invididuals with comparatively high levels of metals had nephrotoxic lesions of a similar type and severity. Moreover, the metal concentrations at which damage began and at which biochemical changes could be detected were below those presently considered as relatively safe for humans by the World Health Organization.

  2. New Vanadium and Manganese Oxides for Lithium Batteries

    NASA Astrophysics Data System (ADS)

    Whittingham, M. Stanley; Zavalij, Peter Y.; Chirayil, Thomas; Chen, Rongji

    1997-03-01

    Transition metal oxides, that can intercalate lithium ions in a reversible manner and with an energy in the range of 3 to 4 volts, are a critical link in the advancement of high energy density lithium batteries. Vanadium, manganese and iron oxides form the appropriate polyhedral structures that might intercalate small ions. Such structures have been formed at low temperatures under conditions of kinetic rather than thermodynamic control. In the case of vanadium six new compounds have been formed using the tetramethylammonium ion, TMA, as the structure directing agent. One of these is a new form of vanadium dioxide, a perfect form of the vanadium pentoxide structure, which is electrochemically active and can intercalate a wide range of molecular and ionic species. Others contain the TMA cation and have layered lattices. A new magnetically active form of nickel manganate has also been synthesized, as have several layered alkali metal manganese oxides with the titanium disulfide type lattice. Their structural characterization and property determination will be described. Supported by NSF-DMR.

  3. MANGANESE--2002 49.1 By Lisa A. Corathers

    E-print Network

    Torgersen, Christian

    MANGANESE--2002 49.1 MANGANESE By Lisa A. Corathers Domestic survey data and tables were prepared Logistics Agency issued on October 1, 2002, was the same with respect to manganese as in the revised fiscal year 2002 AMP issued on October 1, 2001, with the exception of the manganese ferrogroup. The AMP

  4. MANGANESE--2003 48.1 By Lisa A. Corathers

    E-print Network

    Torgersen, Christian

    MANGANESE--2003 48.1 MANGANESE By Lisa A. Corathers Domestic survey data and tables were prepared on December 23, 2002, was the same with respect to manganese as in the revised fiscal year 2002 AMP issued September 30, 2003. Under this AMP, the maximum disposal authority for manganese materials was 226

  5. Manganese oxidation by Leptothrix discophora.

    PubMed Central

    Boogerd, F C; de Vrind, J P

    1987-01-01

    Cells of Leptothrix discophora SS1 released Mn2+-oxidizing factors into the medium during growth in batch culture. Manganese was optimally oxidized when the medium was buffered with HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid) at pH 7.5. Manganese-oxidizing activity in the culture medium in which this strain had been grown previously was sensitive to heat, phosphate, Tris, NaN3, HgCl2 NaCl, sodium dodecyl sulfate, and pronase; 0.5 mol of O2 was consumed per mol of MnO2 formed. During Mn2+ oxidation, protons were liberated. With sodium dodecyl sulfate-polyacrylamide gel electrophoresis, two protein-containing bands were detected in the spent culture medium. One band had an apparent molecular weight of 110,000 and was predominant in Mn2+-oxidizing activity. The second product (Mr 85,000) was only detected in some cases and probably represents a proteolytic breakdown moiety of the 110,000-Mr protein. The Mn2+-oxidizing factors were associated with the MnO2 aggregates that had been formed in spent culture medium. After solubilization of this MnO2 with ascorbate, Mn2+-oxidizing activity could be recovered. Images PMID:3804969

  6. Iron overdose

    MedlinePLUS

    Iron is an ingredient in many mineral and vitamin supplements. Iron supplements are also sold by themselves. Types include: Ferrous sulfate (Feosol, Slow Fe) Ferrous gluconate (Fergon) Ferrous fumarate (Femiron, Feostat) Note: This list may not be all-inclusive.

  7. UPTAKE OF HEAVY METALS IN BATCH SYSTEMS BY A RECYCLED IRON-BEARING MATERIAL

    EPA Science Inventory

    An iron-bearing material deriving from surface finishing operations in the manufacturing of cast-iron components demonstrates potential for removal of heavy metals from aqueous waste streams. Batch isotherm and rate experiments were conducted for uptake of cadmium, zinc, and lead...

  8. The aluminosilicate fraction of North Pacific manganese nodules

    USGS Publications Warehouse

    Bischoff, J.L.; Piper, D.Z.; Leong, K.

    1981-01-01

    Nine nodules collected from throughout the deep North Pacific were analyzed for their mineralogy and major-element composition before and after leaching with Chester-Hughes solution. Data indicate that the mineral phillipsite accounts for the major part (> 75%) of the aluminosilicate fraction of all nodules. It is suggested that formation of phillipsite takes place on growing nodule surfaces coupled with the oxidation of absorbed manganous ion. All the nodules could be described as ternary mixtures of amorphous iron fraction (Fe-Ti-P), manganese oxide fraction (Mn-Mg Cu-Ni), and phillipsite fraction (Al-Si-K-Na), these fractions accounting for 96% of the variability of the chemical composition. ?? 1981.

  9. Manganese carbonate mineralization in the Molango district, Mexico

    USGS Publications Warehouse

    Okita, P.M.

    1992-01-01

    Mn carbonate mineralization is hosted by a finely laminated Upper Jurassic marine sedimentary sequence that forms the base of the Chipoco facies of the Taman Formation (Kimmeridgian). The carbonate ore bed consists of fine-grained rhodochrosite and dispersed organic matter, magnetite, and maghemite but generally only trace quantities of pyrite. Fine laminations and clotted textures suggest deposition in a restricted marine environment. Several geologic and geochemical processes resulted in the formation of Mn carbonate by the early diagenetic reduction of Mn oxides through the oxidation of organic matter and iron sulfide. The ultimate source of the manganese is uncertain but may have been fluvial-sediment loads or hydrothermal activity associated with the rifting of the Gulf of Mexico. -from Author

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

    SciTech Connect

    Recknagel, Sebastian, E-mail: sebastian.recknagel@bam.de [BAM Federal Institute for Materials Research and Testing, Department of Analytical Chemistry, Reference Materials, Richard-Willstätter-Straße 11, D-12489 Berlin (Germany); Radant, Hendrik [BAM Federal Institute for Materials Research and Testing, Department of Analytical Chemistry, Reference Materials, Richard-Willstätter-Straße 11, D-12489 Berlin (Germany); Kohlmeyer, Regina [German Federal Environment Agency (UBA), Section III 1.6 Extended Producer Responsibility, Wörlitzer Platz 1, D-06844 Dessau-Roßlau (Germany)

    2014-01-15

    Highlights: • A well selected sample of 146 batteries was analysed for its heavy metals content. • A comparison was made between heavy metals contents in batteries in 2006 and 2011. • No significant change after implementation of the new EU Batteries Directive. • Severe differences in heavy metal contents were found in different battery-types. - Abstract: The objective of this work was to provide updated information on the development of the potential impact of heavy metal containing batteries on municipal waste and battery recycling processes following transposition of the new EU Batteries Directive 2006/66/EC. A representative sample of 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.

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

    PubMed

    Recknagel, Sebastian; Radant, Hendrik; Kohlmeyer, Regina

    2014-01-01

    The objective of this work was to provide updated information on the development of the potential impact of heavy metal containing batteries on municipal waste and battery recycling processes following transposition of the new EU Batteries Directive 2006/66/EC. A representative sample of 146 different types of commercially available dry and button cells as well as lithium-ion accumulators for mobile phones were analysed for their mercury (Hg)-, cadmium (Cd)- and lead (Pb)-contents. The methods used for preparing the cells and analysing the heavy metals Hg, Cd, and Pb were either developed during a former study or newly developed. Several batteries contained higher mass fractions of mercury or cadmium than the EU limits. Only half of the batteries with mercury and/or lead fractions above the marking thresholds were labelled. Alkaline-manganese mono-cells and Li-ion accumulators, on average, contained the lowest heavy metal concentrations, while zinc-carbon batteries, on average, contained the highest levels. PMID:24139728

  12. Eat Iron?!!

    NSDL National Science Digital Library

    NSF GK-12 and Research Experience for Teachers (RET) Programs,

    To gain an understanding of mixtures and the concept of separation of mixtures, students use strong magnets to find the element of iron in iron-fortified breakfast cereal flakes. Through this activity, they see how the iron component of this heterogeneous mixture (cereal) retains its properties and can thus be separated by physical means.

  13. CADMIUM AS A RESPIRATORY TOXICANT

    EPA Science Inventory

    Cadmium is a major respiratory toxicant as evidenced by numerous human and animal studies. Controlled animal inhalation studies provide supporting evidence to the associations observed in epidemiological studies that Cd has the potential to cause lung fibrosis, emphysema, cancer,...

  14. Discovery of the Cadmium Isotopes

    E-print Network

    S. Amos; M. Thoennessen

    2009-10-22

    Thirty-seven cadmium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  15. The geomicrobiology of iron in deep-sea hydrothermal plumes (Invited)

    NASA Astrophysics Data System (ADS)

    Dick, G.; Li, M.; Toner, B. M.; Cron-Kamermans, B.; Baker, B. J.; Breier, J. A.; Sheik, C. S.

    2013-12-01

    Deep-sea hydrothermal vents are a significant source of iron and manganese to the oceans. Microorganisms in deep-sea hydrothermal plumes can influence the form and oceanic fate of vent-derived iron and manganese in several ways, including catalyzing the formation of iron and manganese oxides as well as binding and stabilizing iron with microbially-produced organic carbon. Although the potential role of organic ligands in dispersal of iron from vents is now well established, the nature and source of this organic matter is unknown. Here we present metagenomic, metatranscriptomic, and geochemical insights into the geomicrobiology of iron in deep-sea hydrothermal plumes of the Guaymas Basin (Gulf of California) and Mid-Cayman Rise (Caribbean). In the Guaymas Basin, genes involved in cellular iron uptake pathways, especially those involving siderophores, are among the most highly expressed genes in the plume microbial community. The nature of these microbial iron transporters, taken together with the low concentration of dissolved iron and abundance of particulate iron (mainly maghemite, lepidocrocite, and hematite) in the plume, indicates that iron minerals are the target for this microbial scavenging and uptake. All major Guaymas plume populations, including widespread methanotrophs, lithotrophs, and a particle-associated heterotroph, participate in iron uptake. At the Mid-Cayman Rise, an abundant plume population of Methylophaga has a cluster of genes involved in siderophore production and uptake that are expressed in the plume. These genes are not present in the genomes of other closely-related Methylophaga. Our findings indicate that the mobilization and cellular uptake of iron is a major process in deep-sea hydrothermal plume microbial communities and suggest new mechanisms for generating Fe-C complexes. This 'microbial iron pump' could represent an important yet previously overlooked mode of converting hydrothermal iron into bioavailable forms that can be dispersed through the oceans.

  16. OXIDATION AND SORPTION KINETICS OF ARSENIC ON A POORLY CRYSTALLINE MANGANESE OXIDE

    E-print Network

    Sparks, Donald L.

    OXIDATION AND SORPTION KINETICS OF ARSENIC ON A POORLY CRYSTALLINE MANGANESE OXIDE by Brandon J MANGANESE OXIDE by Brandon J. Lafferty Approved..........................................................................................................1 Manganese Oxides...................................

  17. Manganese peroxidase gene transcription in Phanerochaete chrysosporium: activation by manganese.

    PubMed Central

    Brown, J A; Alic, M; Gold, M H

    1991-01-01

    The expression of manganese peroxidase in nitrogen-limited cultures of Phanerochaete chrysosporium is dependent on Mn, and initial work suggested that Mn regulates transcription of the mnp gene. In this study, using Northern (RNA) blot analysis of kinetic, dose-response, and inhibitor experiments, we demonstrate unequivocally that Mn regulates mnp gene transcription. The amount of mnp mRNA in cells of 4-day-old nitrogen-limited cultures is a direct function of the concentration of Mn in the culture medium up to a maximum of 180 microM. Addition of Mn to nitrogen-limited Mn-deficient secondary metabolic (4-, 5-, and 6-day-old) cultures results in the appearance of mnp mRNA within 40 min. The appearance of this message is completely inhibited by the RNA synthesis inhibitor dactinomycin but not by the protein synthesis inhibitor cycloheximide. Furthermore, the amount of mnp mRNA produced is a direct function of the concentration of added Mn. In contrast, addition of Mn to low-nitrogen Mn-deficient 2- or 3-day-old cultures does not result in the appearance of mnp mRNA. Manganese peroxidase protein is detected by specific immunoprecipitation of the in vitro translation products of poly(A) RNA isolated from Mn-supplemented (but not from Mn-deficient) cells. All of these results demonstrate that Mn, the substrate for the enzyme, regulates mnp gene transcription via a growth-stage-specific and concentration-dependent mechanism. Images PMID:2061289

  18. Luminescence-based whole-cell-sensing systems for cadmium and lead using genetically engineered bacteria.

    PubMed

    Shetty, Ranjit S; Deo, Sapna K; Shah, Puja; Sun, Yan; Rosen, Barry P; Daunert, Sylvia

    2003-05-01

    Whole-cell-based sensing systems that respond to cadmium and lead ions have been designed and developed using genetically engineered bacteria. These systems take advantage of the ability of certain bacteria to survive in environments polluted with cadmium and lead ions. The bacteria used in this investigation have been genetically engineered to produce reporter proteins in response to the toxic ions. This was achieved by modifying a strain of Escherichia colito harbor plasmids pYSC1 and pYS2/pYSG1. In these dual-plasmid-based sensing systems, the expression of the reporters beta-galactosidase and red-shifted green fluorescent protein (rs-GFP) was controlled by CadC, the regulatory protein of the cad operon. Regulation of the expression of the reporter proteins is related to the amount of cadmium and lead ions employed to induce the bacteria. The bacterial sensing systems were found to respond to cadmium, lead, and zinc ions, and had no significant response to nickel, copper, manganese, and cobalt. PMID:12734613

  19. Manganese biosorption sites of Saccharomyces cerevisiae.

    PubMed

    Parvathi, K; Nareshkumar, R; Nagendran, R

    2007-07-01

    Experiments conducted by pre-treating the fermentation industrial waste biomass of Saccharomyces cerevisiae with laboratory grade chemicals like formaldehyde-formic acid, ethanol, triethyl phosphite-nitromethane, dithiopyridine and benzene helped in studying the roles played by amines, carboxylic acids, phosphates, sulfhydryl group and lipids present on the cell wall of the biomass in manganese biosorption. Potentiometric titration of S. cerevisiae revealed the presence of carboxyl, phosphate, amine groups. The extent of the contribution of the functional groups and lipids to manganese biosorption was in the order: carboxylic acids > amines > lipids > phosphates. Blocking of sulfhydryl group did not have any significant effect on manganese uptake. PMID:17674651

  20. Chronic manganese poisoning: A neuropathological study with determination of manganese distribution in the brain

    Microsoft Academic Search

    M. Yamada; S. Ohno; I. Okayasu; R. Okeda; S. Hatakeyama; H. Watanabe; K. Ushio; H. Tsukagoshi

    1986-01-01

    An autopsy case of a 52-year-old man suffering from chronic manganese poisoning (CMP) is reported with determination of the manganese distribution in the brain. The patient had been working in a manganese ore crushing plant since 1965. In 1967 he began to complain of difficulties in walking and diminished libido. Later, he developed various neuro-psychiatric symptoms including euphoria, emotional incontinence,

  1. Characterisation and Processing of Some Iron Ores of India

    NASA Astrophysics Data System (ADS)

    Krishna, S. J. G.; Patil, M. R.; Rudrappa, C.; Kumar, S. P.; Ravi, B. P.

    2013-10-01

    Lack of process characterization data of the ores based on the granulometry, texture, mineralogy, physical, chemical, properties, merits and limitations of process, market and local conditions may mislead the mineral processing entrepreneur. The proper implementation of process characterization and geotechnical map data will result in optimized sustainable utilization of resource by processing. A few case studies of process characterization of some Indian iron ores are dealt with. The tentative ascending order of process refractoriness of iron ores is massive hematite/magnetite < marine black iron oxide sands < laminated soft friable siliceous ore fines < massive banded magnetite quartzite < laminated soft friable clayey aluminous ore fines < massive banded hematite quartzite/jasper < massive clayey hydrated iron oxide ore < manganese bearing iron ores massive < Ti-V bearing magnetite magmatic ore < ferruginous cherty quartzite. Based on diagnostic process characterization, the ores have been classified and generic process have been adopted for some Indian iron ores.

  2. Galactoglucomannan oligosaccharides alleviate cadmium stress in Arabidopsis.

    PubMed

    Ku?erová, Danica; Kollárová, Karin; Zelko, Ivan; Vatehová, Zuzana; Lišková, Desana

    2014-04-15

    Our study focused on the mediatory role of galactoglucomannan oligosaccharides (GGMOs) in plant protection against cadmium stress, examined mainly on the primary root growth of Arabidopsis thaliana. The application of GGMOs diminished the negative effect of cadmium on root length, root growth dynamics and also on photosynthetic pigment content. We tested the hypothesis that the effect of GGMOs is associated with decreased cadmium accumulation or its modified distribution. Cadmium distribution was observed chronologically from the first day of plant culture and depended on the duration of cadmium treatment. First, cadmium was stored in the root and hypocotyl and later transported by xylem to the leaves and stored there in trichomes. The protective effect of GGMOs was not based on modified cadmium distribution or its decreased accumulation. In cadmium and GGMOs+cadmium-treated plants, the formation of suberin lamellae was shifted closer to the root apex compared to the control and GGMOs. No significant changes between cadmium and GGMOs+cadmium variants in suberin lamellae development corresponded with any differences in cadmium uptake. GGMOs also stimulated Arabidopsis root growth under non-stress conditions. In this case, suberin lamellae were developed more distantly from the root apex in comparison with the control. Faster solute and water transport could explain the faster plant growth induced by GGMOs. Our results suggest that, in cadmium-stressed plants, GGMOs' protective action is associated with the response at the metabolic level. PMID:24655387

  3. Dietary exposure to cadmium and health effects: impact of environmental changes.

    PubMed Central

    Piscator, M

    1985-01-01

    Cadmium exposure, metabolism, and effects are described especially in relation to dietary intakes. Data on dietary intakes in several countries have been complied from studies using the duplicate diet method or fecal analysis. These two methods seem to give more accurate data than estimates based on cadmium concentrations in food classes and food consumption (composite method). The present data on absorption and retention of ingested cadmium indicate that normally less than 5% is ingested, but absorption may increase in women who have iron deficiency. Earlier estimates of the critical concentration in renal cortex being about 200 mg/kg wet weight still seem to be valid. New information is available on present renal levels and their distribution in the general population. The present margin of safety with regard to risk for renal effects is small. To predict future health risks from increases in dietary cadmium due to environmental changes such as acid deposition, it is necessary that the models used are based on correct assumptions. Of interest are the distributions of dietary intake, gastrointestinal absorption, and renal cadmium concentrations. These distributions are normal or lognormal, and since standard deviations are used when estimating risks, it is of paramount importance that the standard deviations are estimated as accurately as possible. At present it is not possible to quantify the effects attributed to acid rain only; account must be also be taken of cadmium added to, e.g., soil by use of sewage sludge and other fertilizers. In addition to risks to human health, cadmium also poses a threat to horses, which generally have renal cadmium concentrations several times higher than adult humans. It is recommended that horses should be monitored in areas when acid deposition is high. Such monitoring might provide valuable information about impact of acid rain. PMID:4076079

  4. Cadmium detoxification processes in the digestive gland of cephalopods in relation to accumulated cadmium concentrations

    Microsoft Academic Search

    P Bustamante; R. P Cosson; I Gallien; F Caurant; P Miramand

    2002-01-01

    The high concentrations of cadmium recorded in the digestive gland of cephalopods from various temperate and subpolar waters suggest that these molluscs have developed efficient cadmium detoxification mechanisms. The subcellular distribution of cadmium in the digestive gland cells was investigated in seven cephalopod species from the Bay of Biscay (France) and the Faroe Islands. In most species, cadmium was mainly

  5. Cadmium uptake from cadmium-spiked sediments by four freshwater invertebrates

    Microsoft Academic Search

    Bruce W. Kilgour

    1991-01-01

    In an attempt to identify other organisms that may be useful for assessing the pollution status of freshwater sediments, cadmium concentrations of four common benthic organisms exposed to cadmium-spiked sediments were examined. Organisms that accumulate cadmium to relatively higher levels are the most useful for analysis and detection. Further, organisms that have body concentrations of cadmium that are more highly

  6. 21 CFR 73.2775 - Manganese violet.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Identity. The color additive manganese violet...be avoided by good manufacturing practice: Ash...filtrate of 10 grams color additive (shaken occasionally...consistent with good manufacturing practice. (d) Labeling. The color additive and any mixture...

  7. 21 CFR 184.1446 - Manganese chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...ore (MnO2 ), or reduced manganese ore in hydrochloric acid. The resulting solution is neutralized to precipitate heavy metals, filtered, concentrated, and crystallized. (b) The ingredient meets the specifications of the Food...

  8. 21 CFR 184.1446 - Manganese chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...ore (MnO2 ), or reduced manganese ore in hydrochloric acid. The resulting solution is neutralized to precipitate heavy metals, filtered, concentrated, and crystallized. (b) The ingredient meets the specifications of the Food...

  9. 21 CFR 184.1446 - Manganese chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...ore (MnO2 ), or reduced manganese ore in hydrochloric acid. The resulting solution is neutralized to precipitate heavy metals, filtered, concentrated, and crystallized. (b) The ingredient meets the specifications of the Food...

  10. HEALTH ASSESSMENT DOCUMENT FOR MANGANESE. FINAL REPORT

    EPA Science Inventory

    The document evaluates data on occurrence, sources, and transport of manganese in the environment and data on metabolism, pharmacokinetics, laboratory toxicological and epidemiologic studies to determine the nature and dose response relationship of potential health effects on hum...

  11. Cadmium mobility in sediments and soils from a coal mining area on Tibagi River watershed: environmental risk assessment.

    PubMed

    Galunin, Evgeny; Ferreti, Jeferson; Zapelini, Iago; Vieira, Isadora; Ricardo Teixeira Tarley, César; Abrão, Taufik; Santos, Maria Josefa

    2014-01-30

    The risk of cadmium contamination in the Tibagi River watershed (Parana State, Brazil) affected by past coal mining activities was assessed through sorption-desorption modeling for sediment and soil samples. The acidic character of the samples resulted in more competition between the cadmium ions and protons, thereby influencing the cadmium sorption-desorption. The sorption isotherms were fitted to the Langmuir and Freundlich single models and to the dual-site Langmuir-Freundlich (or Sips) model. The single-site models indicated a low-energy character of sorption sites on the sample sorption sites, whereas the dual-site model explained the availability of higher-affinity and lower-affinity non-specific sites. The correlation of the sorption and desorption constants with the physicochemical and mineralogical characteristics of the samples showed that the cadmium sorption behavior was significantly affected by the pH, point of zero charge, and also by the magnesium, aluminum, calcium and manganese amounts. Besides, the desorption rate and hysteresis index suggested a high risk of cadmium mobilization along the Tibagi River basin. PMID:24326121

  12. Toenail, Blood and Urine as Biomarkers of Manganese Exposure

    PubMed Central

    Laohaudomchok, Wisanti; Lin, Xihong; Herrick, Robert F.; Fang, Shona C.; Cavallari, Jennifer M.; Christiani, David C.; Weisskopf, Marc G.

    2011-01-01

    Objective This study examined the correlation between manganese exposure and manganese concentrations in different biomarkers. Methods Air measurement data and work histories were used to determine manganese exposure over a workshift and cumulative exposure. Toenail samples (n=49), as well as blood and urine before (n=27) and after (urine, n=26; blood, n=24) a workshift were collected. Results Toenail manganese, adjusted for age and dietary manganese, was significantly correlated with cumulative exposure in months 7-9, 10-12, and 7-12 before toenail clipping date, but not months 1-6. Manganese exposure over a work shift was not correlated with changes in blood nor urine manganese. Conclusions Toenails appeared to be a valid measure of cumulative manganese exposure 7 to 12 months earlier. Neither change in blood nor urine manganese appeared to be suitable indicators of exposure over a typical workshift. PMID:21494156

  13. Zinc, cadmium and manganese uptake by soybean from two zinc- and cadmium-amended Coastal Plain soils

    Microsoft Academic Search

    M. C. White; R. L. Chaney

    1980-01-01

    Two Coastal Plain soils were used to evaluate the effects of organic matter and Fe and Mn hydrous oxides on Zn phytotoxicity, and on Zn, Cd, and Mn uptake by soybean seedlings. Fertilized Pocomoke sl and Sassafras sl were limed to pH 5.5 and 6.3 with CaCOâ when adding Zn (six levens between 1.3 and 196 mg\\/kg at pH 5.5;

  14. Autonomic function in manganese alloy workers

    SciTech Connect

    Barrington, W.W.; Angle, C.R.; Willcockson, N.K.; Padula, M.A. [Univ. of Nebraska Medical Center, Omaha, NE (United States)] [Univ. of Nebraska Medical Center, Omaha, NE (United States); Korn, T.

    1998-07-01

    The observation of orthostatic hypotension in an index case of manganese toxicity lead to this prospective attempt to evaluate cardiovascular autonomic function and cognitive and emotional neurotoxicity in eight manganese alloy welders and machinists. The subjects consisted of a convenience sample consisting of an index case of manganese dementia, his four co-workers in a frog shop for gouging, welding, and grinding repair of high manganese railway track and a convenience sample of three mild steel welders with lesser manganese exposure also referred because of cognitive or autonomic symptoms. Frog shop air manganese samples 9.6--10 years before and 1.2--3.4 years after the diagnosis of the index case exceeded 1.0 mg/m{sup 3} in 29% and 0.2 mg/m{sup 3} in 62%. Twenty-four-hour electrocardiographic (Holter) monitoring was used to determine the temporal variability of the heartrate (RR{prime} interval) and the rates of change at low frequency and high frequency. MMPI and MCMI personality assessment and short-term memory, figure copy, controlled oral word association, and symbol digit tests were used.

  15. Magnesium and manganese content of halophilic bacteria.

    PubMed

    Médicis, E D; Paquette, J; Gauthier, J J; Shapcott, D

    1986-09-01

    Magnesium and manganese contents were measured by atomic absorption spectrophotometry in bacteria of several halophilic levels, in Vibrio costicola, a moderately halophilic eubacterium growing in 1 M NaCl, Halobacterium volcanii, a halophilic archaebacterium growing in 2.5 M NaCl, Halobacterium cutirubrum, an extremely halophilic archaebacterium growing in 4 M NaCl, and Escherichia coli, a nonhalophilic eubacterium growing in 0.17 M NaCl. Magnesium and manganese contents varied with the growth phase, being maximal at the early log phase. Magnesium and manganese molalities in cell water were shown to increase with the halophilic character of the logarithmically growing bacteria, from 30 mmol of Mg per kg of cell water and 0.37 mmol of Mn per kg of cell water for E. coli to 102 mmol of Mg per kg of cell water and 1.6 mmol of Mn per kg of cell water for H. cutirubrum. The intracellular concentrations of manganese were determined independently by a radioactive tracer technique in V. costicola and H. volcanii. The values obtained by Mn loading represented about 70% of the values obtained by atomic absorption. The increase of magnesium and manganese contents associated with the halophilic character of the bacteria suggests that manganese and magnesium play a role in haloadaptation. PMID:16347151

  16. Manganese and copper in the root plaque of Phragmites australis (cav. ) trin. ex steudel

    SciTech Connect

    St-Cyr, L.; Crowder, A.A. (Queen's Univ., Kingston, Ontario (Canada))

    1990-04-01

    Manganese and copper were found in the iron oxide plaque on roots of Phragmites australis collected at six sampling sites in southern Quebec and Ontario, Canada. Manganese concentration in the plaque, like that of Fe, is correlated with Mn-bound-to-carbonates fraction of the soil/sediment. The Fe:Mn ratio of the plaque resemble the same ratio of Fe:Mn-bound-to-carbonates in the substrate. The ratio changes with environmental conditions, increasing with percentage of water and decreasing with pH. Plants located near flowing water accumulate more Mn (and Fe) in the plaque than plants in other habitats through the summer. Copper concentration in the plaque than plants in other habitats through the summer. Copper concentration in the plaque is pH-dependent and is positively correlated with the amount of Fe and Mn of the plaque, but appears to be related more closely to Mn.

  17. Cadmium biosorption by Sphingomonas paucimobilis biomass

    Microsoft Academic Search

    J. Tangaromsuk; P. Pokethitiyook; M. Kruatrachue; E. S. Upatham

    2002-01-01

    Among microorganisms isolated in Bangkok, the gram-negative bacterium Sphingomonas paucimobilis exhibited the greatest cadmium tolerance. It was able to survive in the medium containing cadmium as high as 200 mg\\/l. However, concentrations of cadmium at 25–200 mg\\/l inhibited its growth. The biosorption properties for cadmium of this bacterial biomass and the effects of environmental factors (i.e., biosorbent type, initial pH

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

    SciTech Connect

    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.

  19. Cadmium Removal from Contaminated Soil by Tunable

    E-print Network

    Chen, Wilfred

    , cadmium, nickel, zinc, and copper (2). Unlike most other organic pollutants, heavy metals cannotCadmium Removal from Contaminated Soil by Tunable Biopolymers G I R I D H A R P R A B H U K U M A R-binding biopolymer with high affinity toward cadmium. By taking advantage of the property of ELPH12 to undergo

  20. Cadmium uptake by Emiliania huxleyi (Prymnesiophyceae)

    E-print Network

    Peng, Chieh

    1990-01-01

    to test the relationship with planktonic cultures, uptake of cadmium by Emi liani a huxleyi (Prymnesiophyceae), a calcareous-shelled phytoplankton, was studied. The study of uptake and release of cadmium by coccolithophorids may provide some.... Behavior in seawater. Bioaccumulation. MATERIALS AND METHODS. . Materials. Cultures, Seawater Media. Radioactive 109Cd solution. Methods. General methods. . . Specific methods. . RESULTS. . . . . Growth experiment. . Cadmium uptake...