Science.gov

Sample records for essential trace metals

  1. Effect of metal chelators on excretion and tissue levels of essential trace elements

    SciTech Connect

    Tandon, S.K.; Jain, V.K.; Mathur, A.K.

    1984-10-01

    The influence of one, three, and six doses of ethylenediaminetetraacetic acid (EDTA) diethylenetriaminepentaacetic acid (DTPA), and triethylenetetramine (TETA) on the urinary excretion of Ca, Cu, Fe, and Zn, and on their levels in liver, kidneys, heart, and serum in rats, was investigated to ascertain their suitability in amelioration of metal intoxication. While excretion of all the essential trace metals examined was enhanced significantly, the tissue and serum levels of some of them either increased or decreased after administration of the chelators. The results suggest depletion of some of the endogenous trace metals from the body and their intertissue redistribution following treatment with these chelating agents.

  2. Characterization of metal-peptide complexes in feed supplements of essential trace elements.

    PubMed

    Yiannikouris, Alexandros; Connolly, Cathal; Power, Ronan; Lobinski, Ryszard

    2009-01-01

    Metal chelates with biomolecules are increasingly used in animal supplementation to increase the bioavailability of essential trace elements. However, the transfer of the chelates is not well understood and speciation studies may bring a comprehensive insight to further investigate the biological uptake mechanism(s) implicated. An analytical method was developed for the characterization of the water-soluble metal complexes in animal feed supplements obtained by reaction of a metal salt with a non-GMO soybean enzymatic digest. The method was based on fractionation of the extract by size-exclusion chromatography followed by the analysis of the metal-containing fraction by reversed-phase nanoHPLC with parallel ICP MS and electrospray MS/MS detection. The metal complexes were identified in the mass spectra owing to the Cu characteristic isotopic pattern; the complexation was corroborated by the presence of a peak corresponding to the non-metallated peptide. The study demonstrated the feasibility of SEC-ICP MS to produce characteristic metal (Cu, Zn, Mn, Fe) distribution patterns, which can be of interest to test batch-to-batch reproducibility and to determine the origin of the supplement. The use of the method could be extended to animal feeds prepared using the metal-chelated complexes. Electrospray MS/MS allowed the identification of a number of Cu complexes with peptides. Four different structure conformations were modeled by means of molecular mechanics investigations to assess the chelation stability. PMID:21305120

  3. HAIR HEAVY METAL AND ESSENTIAL TRACE ELEMENT CONCENTRATION IN CHILDREN WITH AUTISM SPECTRUM DISORDER.

    PubMed

    Tabatadze, T; Zhorzholiani, L; Kherkheulidze, M; Kandelaki, E; Ivanashvili, T

    2015-11-01

    Our study aims evaluation of level of essential trace elements and heavy metals in the hair samples of children with autistic spectrum disorder (ASD) and identification of changes that are associated with autistic spectrum disorders. Case-control study was conducted at Child Development Center of Iashvili Children's Central Hospital (LD).We studied 60 children aged from 4 to 5 years old. The concentrations of 28 elements among (Ca,Zn, K, Fe, Cu, Se, Mn, Cr, S, Br, Cl, Co, Ag, V, Ni, Rb, Mo, Sr, Ti, Ba, Pb, As, Hg, Cd, Sb, Zr, Sn, Bi) them trace elements and toxic metals) were determined in scalp hair samples of children (n=30) with autistic spectrum disorder (ASD) and from control group of healthy children (n=30) with matched sex and age. Micro-elemental status was detected in the hair, with roentgen-fluorescence spectrometer method (Method MBИ 081/12-4502-000, Apparatus ALVAX- CIP, USA - UKRAIN) .To achieve the similarity of study and control groups, pre and postnatal as well as family and social history were assessed and similar groups were selected. Children with genetic problems, malnourished children, children from families with social problems were excluded from the study. The diagnosis of ASD were performed by pediatrician and psychologist (using M-CHAT and ADOS) according to DSM IV (Diagnostic and Statistical Manual of Mental Disorders from the American Psychiatric association) criteria. The study was statistically analyzed using computer program SPSS 19. Deficiencies of essential trace microelements revealed in both group, but there was significant difference between control and studied groups. The most deficient element was zinc (92% in target and 20% in control), then - manganese (55% and 8%) and selenium (38% and 4%). In case of cooper study revealed excess concentration of this element only in target group in 50% of cases. The contaminations to heavy metals were detected in case of lead (78% and 16), mercury (43% and 10%) and cadmium (38% and 8%). The

  4. Blood concentration of essential trace elements and heavy metals in workers exposed to lead and cadmium.

    PubMed

    Wasowicz, W; Gromadzińska, J; Rydzyński, K

    2001-01-01

    The aim of the study was to determine blood concentration of essential trace elements (Se, Zn, Cu) and toxic metals (Pb, Cd), markers of antioxidant (activities of glutathione peroxidase (GPx), superoxidase dismutase and ceruloplasmin) and prooxidant processes (thiobarbituric acid reactive substances (TBARS)) in workers exposed to Pb and Cd. Forty three male workers of the lead-acid batteries department, aged 25-52 years, and twenty two workers, including 15 women, aged 36-51 years, exposed to Cd in the alkaline batteries department were examined. The reference group consisted of 52 healthy inhabitants of the same region. It was found that Se concentration and GPx activity in both erythrocytes and plasma of Cd exposed workers were significantly lower (p < 0.001) than in the reference group. We found an inverse linear correlation between blood Se and Cd concentrations in the workers exposed to Cd (r = -0.449; p < 0.01). Moreover, the activity of erythrocyte and plasma GPx was shown to be significantly lower in the study group of workers (p < 0.001). It was observed that TBARS concentration in plasma was significantly higher (p < 0.05) in the lead exposed workers than in the group without contact with Pb. Our results indicate that exposure to Pb and Cd affects the antioxidant potential of blood in workers exposed to heavy metals. PMID:11764849

  5. Subcellular partitioning of non-essential trace metals (Ag, As, Cd, Ni, Pb, and Tl) in livers of American (Anguilla rostrata) and European (Anguilla anguilla) yellow eels.

    PubMed

    Rosabal, Maikel; Pierron, Fabien; Couture, Patrice; Baudrimont, Magalie; Hare, Landis; Campbell, Peter G C

    2015-03-01

    We determined the intracellular compartmentalization of the trace metals Ag, As, Cd, Ni, Pb, and Tl in the livers of yellow eels collected from the Saint Lawrence River system in Canada (Anguilla rostrata) and in the area of the Gironde estuary in France (Anguilla anguilla). Differential centrifugation, NaOH digestion and thermal shock were used to separate eel livers into putative "sensitive" fractions (heat-denatured proteins, mitochondria and microsomes+lysosomes) and detoxified metal fractions (heat-stable peptides/proteins and granules). The cytosolic heat-stable fraction (HSP) was consistently involved in the detoxification of all trace metals. In addition, granule-like structures played a complementary role in the detoxification of Ni, Pb, and Tl in both eel species. However, these detoxification mechanisms were not completely effective because increasing trace metal concentrations in whole livers were accompanied by significant increases in the concentrations of most trace metals in "sensitive" subcellular fractions, that is, mitochondria, heat-denatured cytosolic proteins and microsomes+lysosomes. Among these "sensitive" fractions, mitochondria were the major binding sites for As, Cd, Pb, and Tl. This accumulation of non-essential metals in "sensitive" fractions likely represents a health risk for eels inhabiting the Saint Lawrence and Gironde environments. PMID:25635611

  6. New Perspectives on the Essential Trace Elements.

    ERIC Educational Resources Information Center

    Frieden, Earl

    1985-01-01

    Provides a comprehensive overview of the 19 essential trace elements, examining: the concept of essentiality; evolution of these elements; possible future essential elements; the lanthanides and actinides; how essential trace elements work; the metalloenzymes; the nonmetals; iodine and the thyroid hormones; and antagonism among these elements. (JN)

  7. Influence of essential trace minerals and micronutrient insufficiencies on harmful metal overload in a Mongolian patient with multiple sclerosis.

    PubMed

    Komatsu, Fumio; Kagawa, Yasuo; Kawabata, Terue; Kaneko, Yoshinori; Kudoh, Hideki; Purvee, Baatar; Otgon, Jugder; Chimedregzen, Ulziiburen

    2012-07-01

    Parkinson's disease and other neurological disorders are prevalent in Mongolia. Our previous studies revealed a significant correlation of these diseases with high oxidative stress due to a high body burden of harmful metals, such as manganese, iron, lead, cadmium, and aluminum. This report describes a 37-year-old male Mongolian patient with multiple sclerosis and essential micronutrient deficiency. This patient demonstrated high oxidative stress, as shown by high urinary 8-hydroxy-2'-deoxyguanosine levels of 14.7 and 14.3 ng/mg creatinine (crea), although his hair levels of these toxic metals were markedly lower than other Mongolians. In addition, this patient was deficient not only in various essential minerals, including selenium, magnesium, copper, cobalt, vanadium, and nickel, but also in micronutrients such as vitamin B6, C, E, folic acid, niacin, and β-carotene. Furthermore, after taking 2,3-dimercaptosuccinic acid, a chelating agent, urinary excretion of lead, cadmium, manganese, aluminum, iron, copper, and lithium were increased 156-, 8.4-, 7.6-, 4.3-, 3.3-, 2.1-, and 2.1-fold, respectively. These results suggest that this patient suffered from a deficiency in micronutrients such as essential minerals and vitamins, which resulted in a disturbance in the ability to excrete harmful metals into the urine and hair. It is possible that a deficiency of micronutrients and a high burden of heavy metals play a role in the pathogenesis of multiple sclerosis. Nutritional treatment may be an effective approach to this disease. PMID:21834785

  8. Limitation of productivity by trace metals in the sea

    SciTech Connect

    Morel, F.M.M.; Price, N.M. ); Hudson, R.J.M. )

    1991-12-01

    Some trace metals such as Fe, Ni, Cu, and Zn are essential for the growth of phytoplankton. The concentrations of these essential trace elements in seawater are so low as to limit their availability to aquatic microbiota. Trace element uptake is ultimately limited by kinetics of reaction with transport ligands or by diffusion to the cell. From what the authors know of the characteristics of the uptake systems of phytoplankton and their trace metal requirements they can estimate that Fe and Zn may at some times in some place limit phytoplankton productivity, which is in accord with available field data on trace metal enrichments.

  9. Trace metal transformations in gasification

    SciTech Connect

    Benson, S.A.; Erickson, T.A.; O`Keefe, C.A.; Katrinak, K.; Allan, S.E.; Hassett, D.J.; Hauserman, W.B.; Zygarlicke, C.J.

    1995-11-01

    The Energy and Environmental Research Center (EERC) is carrying out an investigation that will provide methods to predict the fate of selected trace elements in integrated gasification combined cycle (IGCC) and integrated gasification fuel cell (IGFC) systems to aid in the development of methods to control the emission of trace elements determined to be air toxics. The goal of this project is to identify the effects of critical chemical and physical transformations associated with trace element behavior in IGCC and IGFC systems. The trace elements included in this project are arsenic, chromium, cadmium, mercury, nickel, selenium, and lead. The research seeks to identify and fill, experimentally and/or theoretically, data gaps that currently exist on the fate and composition of trace elements. The specific objectives are to (1) review the existing literature to identify the type and quantity of trace elements from coal gasification systems; (2) perform laboratory-scale experimentation and computer modeling to enable prediction of trace element emissions; and (3) identify methods to control trace element emissions. Results are presented and discussed on the partitioning of trace metals and the model design for predicting trace metals behavior.

  10. Controls of Trace Metals in Seawater

    NASA Astrophysics Data System (ADS)

    Bruland, K. W.; Lohan, M. C.

    2003-12-01

    the impetus for such a program comes from the recognition of iron as an important micronutrient influencing global biogeochemical cycles in the oceans (Moore et al., 2002) and the potential role of other trace metals such as zinc. In particular, there is a pressing need for an expansion of the global database of dissolved iron distributions in the oceans. These measurements are needed to both initiate and verify models and to identify processes not contained in existing models.There have been a number of reviews of trace elements in seawater that form a foundation for this chapter. Among them are: Bruland (1983) on oceanographically consistent data sets; Burton and Statham (1990) on trace metals in seawater; and Donat and Bruland (1995) on trace elements in oceans. There are two reviews that deal with more of the biological role of trace metals: Bruland et al. (1991) on interactive influence of bioactive trace metals on biological production in ocean waters; and Hunter et al. (1997) on biological roles of trace metals in natural waters. A highly complementary chapter in this Treatise that deals with the influence of essential trace metals on biological processes has been written by Morel et al. (Chapter 6.05). Turning to "on-line" sources of information, Nozaki has done an excellent job perusing the available literature and compiling vertical profiles from the North Pacific for each element in a periodic table that makes an excellent figure (http://www.agu.org/eos_elec/97025e.html). Ken Johnson, a marine chemist at the Monterey Bay Aquarium Research Institute (MBARI), has a web site with a periodic table of the elements containing a brief review of information on each element (http://www.mbari.org/chemsensor/pteo.htm).

  11. Trace metal speciation and bioavailability in anaerobic digestion: A review.

    PubMed

    Thanh, Pham Minh; Ketheesan, Balachandran; Yan, Zhou; Stuckey, David

    2016-01-01

    Trace metals are essential for the growth of anaerobic microorganisms, however, in practice they are often added to anaerobic digesters in excessive amounts, which can lead to inhibition. The concept of bioavailability of metals in anaerobic digestion has been poorly understood in the past, and a lack of deep understanding of the relationship between trace metal speciation and bioavailability can result in ineffective metal dosing strategies for anaerobic digesters. Sequential extraction schemes are useful for fractionating trace metals into their different forms, and metal sulfides can serve as a store and source for trace metals during anaerobic digestion, while natural/synthetic chelating agents (soluble microbial products-SMPs, extracellular polysaccharides-EPS, and EDTA/NTA) are capable of controlling trace metal bioavailability. Nevertheless, more work is needed to: investigate the speciation and bioavailability of Ca, Mg, Mn, W, and Se; compare the bioavailability of different forms of trace metals e.g. carbonates, sulfides, phosphates to different anaerobic trophic groups; determine what factors influence metal sulfide dissolution; investigate whether chelating agents can increase trace metal bioavailability; develop and adapt specialized analytical techniques, and; determine how trace metal dynamics change in an anaerobic membrane bioreactor (AnMBR). PMID:26707985

  12. Heavy Metals and Related Trace Elements.

    ERIC Educational Resources Information Center

    Leland, Harry V.; And Others

    1978-01-01

    Presents a literature review of heavy metals and related trace elements in the environment, covering publications of 1976-77. This review includes: (1) trace treatment in natural water and in sediments; and (2) bioaccumulation and toxicity of trace elements. A list of 466 references is presented. (HM)

  13. Evaluation of metal trace detachment from dosing pumps using PIXE

    NASA Astrophysics Data System (ADS)

    Lozano, Omar; Mejia, Jorge; Laloy, Julie; Alpan, Lütfiye; Toussaint, Olivier; Dogné, Jean-Michel; Lucas, Stéphane

    2014-07-01

    Metal trace detachment evaluation is essential for instruments destined for pharmaceutical applications, such as pumps. Particle-Induced X-ray Emission (PIXE) was used to determine and quantify metal traces originated from stainless steel and ceramic dosing pumps. Metal traces were quantified from either distilled water samples or cellulose filters in two tests: a short-term test of 16 h mimicking a daily cycle of a dosing pump for industrial applications, and a long-term test of 9 days evaluating the pump wearing. The main result is that ceramic dosing pumps present lower metal detachment than stainless steel counterparts. Traces of Si and Al were found originating from pieces around the pumps (pipes and joints).

  14. TRACE METAL TRANSFORMATION MECHANISMS DURING COAL COMBUSTION

    EPA Science Inventory

    The article reviews mechanisms governing the fate of trace metals during coal combustion and presents new theoretical results that interpret existing data. Emphasis is on predicting the size-segregated speciation of trace metals in pulverized-coal-fired power plant effluents. Thi...

  15. TRACE METAL TRANSFORMATION MECHANISMS DURING COAL COMBUSTION

    EPA Science Inventory

    The article reviews mechanisms governing the fate of trace metals during coal combustion and presents new theoretical results that interpret existing data. mphasis is on predicting the size-segregated speciation of trace metals in pulverized-coal-fired power plant effluents. his ...

  16. Analytical Methods for Trace Metals. Training Manual.

    ERIC Educational Resources Information Center

    Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

    This training manual presents material on the theoretical concepts involved in the methods listed in the Federal Register as approved for determination of trace metals. Emphasis is on laboratory operations. This course is intended for chemists and technicians with little or no experience in analytical methods for trace metals. Students should have…

  17. Extraction of trace metals from fly ash

    DOEpatents

    Blander, Milton; Wai, Chien M.; Nagy, Zoltan

    1984-01-01

    A process for recovering silver, gallium and/or other trace metals from a fine grained industrial fly ash associated with a process for producing phosphorous, the fly ash having a silicate base and containing surface deposits of the trace metals as oxides, chlorides or the like, with the process being carried out by contacting the fly ash with AlCl.sub.3 in an alkali halide melt to react the trace metals with the AlCl.sub.3 to form compositions soluble in the melt and a residue containing the silicate and aluminum oxide or other aluminum precipitate, and separating the desired trace metal or metals from the melt by electrolysis or other separation techniques.

  18. Extraction of trace metals from fly ash

    DOEpatents

    Blander, M.; Wai, C.M.; Nagy, Z.

    1983-08-15

    A process is described for recovering silver, gallium and/or other trace metals from a fine grained industrial fly ash associated with a process for producing phosphorous. The fly ash has a silicate base and contains surface deposits of the trace metals as oxides, chlorides or the like. The process is carried out by contacting the fly ash with AlCl/sub 3/ in an alkali halide melt to react the trace metals with the AlCl/sub 3/ to form compositions soluble in the melt and a residue containing the silicate and aluminum oxide or other aluminum precipitate, and separating the desired trace metal or metals from the melt by electrolysis or other separation techniques.

  19. Trace metal transformations in gasification

    SciTech Connect

    Erickson, T.A.; Zygarlicke, C.J.; O`Keefe, C.A.

    1995-08-01

    The Energy & Environmental Research Center (EERC) is carrying out an investigation that will provide methods to predict the fate of selected trace elements in integrated gasification combined cycle (IGCC) and integrated gasification fuel cell (IGFC) systems to aid in the development of methods to control the emission of trace elements determined to be air toxics. The goal of this project is to identify the effects of critical chemical and physical transformations associated with trace element behavior in IGCC and IGFC systems. The trace elements included in this project are arsenic, chromium, cadmium, mercury, nickel, selenium, and lead. The research seeks to identify and fill, experimentally and/or theoretically, data gaps that currently exist on the fate and composition of trace elements. The specific objectives are to (1) review the existing literature to identify the type and quantity of trace elements from coal gasification systems, (2) perform laboratory-scale experimentation and computer modeling to enable prediction of trace element emissions, and (3) identify methods to control trace element emissions.

  20. Trace metal transformations in gasification

    SciTech Connect

    Benson, S.; Erickson, T.A.; Zygarlicke, C.J.

    1995-12-01

    The Energy & Environmental Research Center (EERC) is carrying out an investigation that will provide methods to predict the fate of selected trace elements in integrated gasification combined cycle (IGCC) and integrated gasification fuel cell (IGFC) systems to aid in the development of methods to control the emission of trace elements determined to be air toxics. The goal of this project is to identify the effects of critical chemical and physical transformations associated with trace element behavior in IGCC and IGFC systems. The trace elements included in this project are arsenic, chromium, cadmium, mercury, nickel, selenium, and lead. The research seeks to identify and fill, experimentally and/or theoretically, data gaps that currently exist on the fate and composition of trace elements. The specific objectives are to (1) review the existing literature to identify the type and quantity of trace elements from coal gasification systems, (2) perform laboratory-scale experimentation and computer modeling to enable prediction of trace element emissions, and (3) identify methods to control trace element emissions.

  1. Trace metal transformation in gasification

    SciTech Connect

    Benson, S.A.; Erickson, T.A.; Zygarlicke, C.J.; O`Keefe, C.A.; Katrinak, K.A.; Allen, S.E.; Hassett, D.J.; Hauserman, W.B.; Holcombe, N.T.

    1996-12-31

    The Energy & Environmental Research Center (EERC) is carrying out an investigation that will provide methods to predict the fate of selected trace elements in integrated gasification combined cycle (IGCC) and integrated gasification fuel cell (IGFC) systems to aid in the development of methods to control the emission of trace elements determined to be air toxics. The goal of this project is to identify the effects of critical chemical and physical transformations associated with trace element behavior in IGCC and IGFC systems. The trace elements included in this project are arsenic, chromium, cadmium, mercury, nickel, selenium, and lead. The research seeks to identify and fill, experimentally and/or theoretically, data gaps that currently exist on the fate and composition of trace elements. The specific objectives are to 1) review the existing literature to identify the type and quantity of trace elements from coal gasification systems, 2) perform laboratory-scale experimentation and computer modeling to enable prediction of trace element emissions, and 3) identify methods to control trace element emissions.

  2. Trace metals in marine sediments of Kuwait

    SciTech Connect

    Anderlini, V.C.; Mohammad, O.S.; Zarba, M.A.; Fowler, S.W.; Miramand, P.

    1982-01-01

    The report presents the results of analyses for ten trace metals (Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn) in marine surface sediments from Kuwait and discusses the effect of grain size and total organic content on the observed concentrations of these metals. (JMT)

  3. Metals essentials for plants: the nickel case.

    PubMed

    Pennazio, Sergio

    2012-01-01

    The long period of research that preceded the discovery of nickel (Ni) essentiality for plants constitutes a paradigmatic case of doubts and uncertainties that often occur in experimental biology. The history of the essentiality of chemical elements that are present as traces in the plant ash (micronutrients) began in the mid-Nineteenth, but it had blurred outlines until Daniel Arnon, towards the mid-twentieth century, fixed the now historic 'criteria of essentiality'. During this rather long time, seven micronutrients were recognised, step by step, as essential for higher plants, (iron, manganese, boron, Zinc, copper, molybdenum, and chloride), at first thanks to meticulous observations of deficiency symptoms and then to the culture of plant on aqueous solutions. The last element to be recognised as essential for plant nutrition was Ni, which was considered a very toxic element for more than a century. Towards the Thirties, Ni became to be regarded as a useful element by some researchers, but the ultimate proof of its essentiality was obtained only in the Eighties, when the American group of Ross M. Welch demonstrated that Ni is a cofactor of the enzyme urease. More recent research shows that Ni improves the nitrogen (N) metabolism and appears to be important for the efficiency of N fixation. PMID:23757955

  4. BIOLOGICAL MONITORING OF TOXIC TRACE METALS. VOLUME 2. TOXIC TRACE METALS IN PLANTS AND ANIMALS OF THE WORLD. PART III

    EPA Science Inventory

    The needs and priorities in using biological accumulator organisms for monitoring toxic trace metals in plants and animals are analyzed. The toxic trace metals selected for study are antimony, arsenic, beryllium, boron, cadmium, chromium, cobalt, copper, lead, mercury, nickel, se...

  5. BIOLOGICAL MONITORING OF TOXIC TRACE METALS. VOLUME 2. TOXIC TRACE METALS IN PLANTS AND ANIMALS OF THE WORLD. PART II

    EPA Science Inventory

    The needs and priorities in using biological accumulator organisms for monitoring toxic trace metals in plants and animals are analyzed. The toxic trace metals selected for study are antimony, arsenic, beryllium, boron, cadmium, chromium, cobalt, copper, lead, mercury, nickel, se...

  6. BIOLOGICAL MONITORING OF TOXIC TRACE METALS. VOLUME 2. TOXIC TRACE METALS IN PLANTS AND ANIMALS OF THE WORLD. PART I

    EPA Science Inventory

    The needs and priorities in using biological accumulator organisms for monitoring toxic trace metals in plants and animals are analyzed. The toxic trace metals selected for study are antimony, arsenic, beryllium, boron, cadmium, chromium, cobalt, copper, lead, mercury, nickel, se...

  7. Correlation between some selected trace metal concentrations in six species of fish from the Arabian Sea

    SciTech Connect

    Ashraf, M.; Jaffar, M.

    1988-07-01

    The role of trace metals in marine ecosystems has been keenly investigated during recent years. It is known that abundance of essential trace metals regulates the metal content in the organisms by homeostatic control mechanisms, which when cease to function cause essential trace metals to act in an either acutely or chronically toxic manner. Therefore, a correlation study based on essential and non-essential trace metal concentrations is imperative for extending the existing knowledge of bioaccumulation of trace metals in marine organisms. An attempt has been made in the present investigation to bring out quantitative correlations between the concentrations of iron, copper, lead and zinc in the edible muscle tissue of six species of marine fish: Salmon (salmon sole); tuna (thunnus thynnus); pomfret silver (pampus argenteus); Pomfret black (formioniger); long tail tuna (thynnus tonggel) and Indian oil sardine (sardinella longiceps). These fish are abundantly available in Pakistan along the coastal line of the Arabian Sea and have great commercial value. The computational analysis on the trace metal correlation was conducted using an MSTAT statistical package.

  8. Trace metal transport by marine microorganisms: implications of metal coordination kinetics

    NASA Astrophysics Data System (ADS)

    Hudson, Robert J. M.; Morel, François M. M.

    1993-01-01

    Marine microorganisms have transport systems capable of accumulating essential trace metals present at low oceanic concentrations—1 pM to 1 nM. In marine phytoplankton, Fe, Mn, Zn and Ni transport has been shown to involve complexation by membrane carriers. By analysing the kinetics of the transport process and accounting for the inherently slow coordination reactions of some of these metals, we predict optimum properties and minimum numbers of sites for the transport systems. Limits to trace metal uptake, and thereby to growth rates, may arise from finite space for these transport sites in the membrane, competition from other metals and the rate of diffusion to the cell. These types of nutrient limitation should exhibit different size dependencies and therefore be important in determining ecosystem structure. The concentrations of inorganically complexed species of nutrient metals remaining in the surface ocean appear to be correlated with predicted rates of metal complexation by trace metal transport sites, suggesting that kinetic liability controls the bioavailability of these metals and their rate of removal from the surface ocean.

  9. Trace metal concentrations in tropical mangrove sediments, NE Brazil.

    PubMed

    Miola, Brígida; Morais, Jáder Onofre de; Pinheiro, Lidriana de Souza

    2016-01-15

    Sediment cores were taken from the mangroves of the Coreaú River estuary off the northeast coast of Brazil. They were analyzed for grain size, CaCO3, organic matter, and trace metal (Cd, Pb, Zn, Cu, Al, and Fe) contents. Mud texture was the predominant texture. Levels of trace metals in surface sediments indicated strong influence of anthropogenic processes, and diagenetic processes controlled the trace metal enrichment of core sediments of this estuary. The positive relationships between trace metals and Al and Fe indicate that Cu, Zn, Pb, and Cd concentrations are associated mainly with Al and Fe oxy-hydroxides and have natural sources. PMID:26608507

  10. Statistical considerations for trace metal biomonitoring

    SciTech Connect

    Daskalakis, K.D.

    1995-12-31

    Collection and chemical analysis of oysters has been done by numerous programs, including the National Status and Trends (NS and T) program, as a convenient and relatively inexpensive method for monitoring contaminant inputs into aquatic environments. It was the goal of this work to quantify the within-site variability in oysters for concentrations of several trace metals. Oysters (Crassostrea virginica) were collected from three sites at the Potomac River and the soft tissue of each animal was analyzed for Ag, Cd, Cu, Fe, Ni, Pb, and Zn. The combined analytical+ within-site Percent Relative Standard Deviation (%RSD) for 20 to 23 individual samples from the same site was between 25 and 97, depending on metal. The order of increasing %RSD was Fe < Cd < Ni < Zn < Pb < Ag < Cu. Triplicate analyses of the samples revealed that the analytical error was significant relative to within-site variability only for Pb, presumably due to low concentrations of the metal. Bootstrap analysis with replacement, a statistical resampling procedure, was used to estimate population parameters for pooled samples. Simulated sampling of 10,000 pooled samples verified that the sampling error decreases exponentially with increasing number of individuals per pool. For 95 percent confidence limit the mean standard error for pooled samples of 20 oysters varied from 5% to 20%, depending on metal. The standard mean error increased by a factor of approximately 1.5 when 10 individuals were used instead of 20, and decreased by a factor of 0.6 when 50 oysters were used per pooled sample. Given these results a cost estimation of monitoring programs will be presented, and implications on trend assessments will be discussed.

  11. Consumer-producer relationships for trace metals in Chorthippus brunneus (Thunberg. )

    SciTech Connect

    Johnson, M.S.

    1986-08-01

    The behavior of trace metals in terrestrial food chains is a subject of ecological interest, particularly in polluted environments where the potential exists for bioconcentration of metals known to be essential in trace amounts for normal plant and animal metabolism, as well as those with no known metabolic function but recognized toxicological properties. Laboratory studies of food chain relationships afford a means by which direct comparisons can be made between trace metals as a basis for interpretation of data collected from wild plant and animal populations. This study compares the behavior of three trace elements, copper, zinc and cadmium, in terms of their assimilation under experimental conditions by the herbivorous common field grasshopper, Chorthippus brunneus (Thunberg.). This voracious orthopteran is widely distributed in Britain and is particularly prominent in the restricted invertebrate community of some metal smelter-affected grasslands where it forms important seasonal prey for insectivorous small mammals.

  12. TOXIC TRACE METALS IN MAMMALIAN HAIR AND NAILS

    EPA Science Inventory

    Data have been compiled from the available world literature on the accumulation and bioconcentration of selected toxic trace metals in human hair and nails and other mammalian hair, fur, nails, claws, and hoofs. The toxic trace metals and metalloids include antimony, arsenic, bor...

  13. TRACE METALS AND STATIONARY CONVENTIONAL COMBUSTION PROCESSES: VOLUME 2. BIBLIOGRAPHY

    EPA Science Inventory

    The report gives results of a search of U.S. literature to identify published information about trace metals and Stationary Conventional Combustion Processes (SCCPs). It summarizes what has been published about ambient trace metals in air, water, and soils, and reviews convention...

  14. Mobilization of trace metals and inorganic compounds during resuspension of anoxic sediments from Trepangier Bayou, Louisiana.

    PubMed

    Shipley, Heather J; Gao, Yan; Kan, Amy T; Tomson, Mason B

    2011-01-01

    The release of trace metals (Mn, Ni, Co, Cu, Zn, Pb, and Cd) and inorganic compounds (As) from initially anoxic Trepangier Bayou sediments, Louisiana and the sources of the released metals were investigated. After 1 to 2 d aeration, significant amounts of trace metals (Mn, Zn, Cd, Ni, and Co) were released to the aqueous phase with increased acidity, primarily due to the oxidation of acid-volatile sulfide and ferrous iron and iron sulfide minerals. The addition of a bacterial inhibitor, NaN,, to the Trepangier sediment during resuspension inhibited metal release, suggesting that microbial catalysis can regulate metal mobilization during sediment resuspension. In a well buffered system, oxidation of iron sulfides alone did not appear to induce trace metal release. Moreover, when Trepangier sediment was resuspended in anoxic conditions at neutral pH, <1% of the trace metal content was released, whereas a significant release of metal was observed under acidic anoxic conditions. Although oxidation of iron sulfide minerals is an essential prerequisite for the release of Zn, Co, Cd, and Ni, carbonates and oxides also play a role. The trace metals and inorganic compounds investigated could be classified into three groups according to their release characteristics: (i) Mn, Zn, Cd, Ni, and Co; (ii) Fe, Pb, and As; and (iii) Cu. The groupings appeared to depend on the sources of compounds and their relative affinity, after oxidation, to iron oxyhydroxides or organic matter. PMID:21520756

  15. Dissolved Trace metal distributions and speciation in Yellow Sea, China

    NASA Astrophysics Data System (ADS)

    Li, Li; Wang, Xiaojing; Zhang, Cuiqin; Liu, Jihua; Shi, Xuefa

    2016-04-01

    Trace metals play an important role in marine biogeochemical cycling processes. However, owing to the lack of trace-metal clean sampling and analytical techniques, high quality data for dissolved trace metals in coastal seawaters of China are scarce. In this study, by employing stringent trace-metal clean sampling and analytical techniques, we investigated spatial distribution patterns of several dissolved trace metals (Cu, Ni, Co, Pb, Cd, Zn, and Ag) in Yellow Sea and Bohai Sea of China, and discussed their potential sources and sinks. In general, the dissolved metal concentrations decreased from Bohai Sea to Yellow Sea, and from nearshore to offshore. Despite the severe contamination status reported in coastal seawaters of China, the trace metal concentrations found in seawater are comparable to the concentrations found in pristine coastal seawaters of the US and the EU. In the meantime, the speciation of several metals (Cu, Pb, Zn, Cd) were also studied with the electrochemical (ASV and CLE-CSV) methods in the Yellow Sea. Natural organic ligands were found in seawaters that strongly complexed with dissolved metals. The concentrations and binding constants of the complexing ligands for each metal were reported and compared with the ones found in other coastal seawaters.

  16. Sandhopper solar orientation as a behavioural biomarker of trace metals contamination.

    PubMed

    Ungherese, Giuseppe; Ugolini, Alberto

    2009-04-01

    Although many studies have focused on trace metals accumulation, investigations of talitrid amphipods as biomarkers are rare. This study explores the possibility of using the solar orientation capacity of Talitrus saltator as a behavioural marker of exposure to two essential (Cu and Zn) and two non-essential (Cd and Hg) metals. LC(50) analyses performed before the solar orientation tests showed that the 72 h LC(50) for Hg was 0.02 ppm while the 96 h LC(50) values for Cu, Cd and Zn were 13.28 ppm, 27.66 ppm, and 62.74 ppm, respectively. The presence of metals in seawater affects the solar orientation capacity of T. saltator in a concentration-dependent manner and according to the toxicity ranking of the metals (Hg > Cu > Cd > Zn). Therefore, the solar orientation capacity of T. saltator seems to be a promising behavioural marker for exposure to trace metals. PMID:19110350

  17. Trace metal concentrations in estuaries and coastal regions

    SciTech Connect

    Hunt, C.D.

    1994-12-31

    Estuaries and coastal regions are highly variable in the physical and hydrographic conditions. As a result of heavy urbanization and industrialization of the head waters of most estuaries, there are substantial localized inputs of contaminants to the estuary. These factors combined with the flushing characteristics of individual estuaries to create relatively unique features that result in variation in the typical levels of trace metals for these systems. This makes intercomparison of the estuaries difficult. Comparability among estuaries becomes even more difficult when metals analyses are conducted without proper control of field and laboratory contamination, now firmly established in the trace metal analytical literature as a prerequisite for reliable marine trace metals analysis. This paper compares the concentrations of selected trace metal (Ag, Cd, Cu, Ni, Pb, and Zn) concentrations in the waters of several major estuaries of the United States. The basis of comparison is that all samples war collected under rigid trace metal clean collection and analysis procedures. Generally, metal concentrations within the estuaries are similar. Metal concentrations in the higher salinity coastal regions are more similar in concentration. The comparison provides a baseline of typical concentrations of these trace metals in the coastal waters against which future analytical results can be compared.

  18. Effects of Trace Metal Concentrations on the Growth of the Coral Endosymbiont Symbiodinium kawagutii

    PubMed Central

    Rodriguez, Irene B.; Lin, Senjie; Ho, Jiaxuan; Ho, Tung-Yuan

    2016-01-01

    Symbiodinium is an indispensable endosymbiont in corals and the most important primary producer in coral reef ecosystems. During the past decades, coral bleaching attributed to the disruption of the symbiosis has frequently occurred resulting in reduction of coral reef coverage globally. Growth and proliferation of corals require some specific trace metals that are essential components of pertinent biochemical processes, such as in photosynthetic systems and electron transport chains. In addition, trace metals are vital in the survival of corals against oxidative stress because these metals serve as enzymatic cofactors in antioxidative defense mechanisms. The basic knowledge about trace metal requirements of Symbiodinium is lacking. Here we show that the requirement of Symbiodinium kawagutii for antioxidant-associated trace metals exhibits the following order: Fe >> Cu/Zn/Mn >> Ni. In growth media with Cu, Zn, Mn, and varying Fe concentrations, we observed that Cu, Zn, and Mn cellular quotas were inversely related to Fe concentrations. In the absence of Cu, Zn, and Mn, growth rates increased with increasing inorganic Fe concentrations up to 1250 pM, indicating the relatively high Fe requirement for Symbiodinium growth and potential functional complementarity of these metals. These results demonstrate the relative importance of trace metals to sustain Symbiodinium growth and a potential metal inter replacement strategy in Symbiodinium to ensure survival of coral reefs in an oligotrophic and stressful environment. PMID:26903964

  19. Effects of Trace Metal Concentrations on the Growth of the Coral Endosymbiont Symbiodinium kawagutii.

    PubMed

    Rodriguez, Irene B; Lin, Senjie; Ho, Jiaxuan; Ho, Tung-Yuan

    2016-01-01

    Symbiodinium is an indispensable endosymbiont in corals and the most important primary producer in coral reef ecosystems. During the past decades, coral bleaching attributed to the disruption of the symbiosis has frequently occurred resulting in reduction of coral reef coverage globally. Growth and proliferation of corals require some specific trace metals that are essential components of pertinent biochemical processes, such as in photosynthetic systems and electron transport chains. In addition, trace metals are vital in the survival of corals against oxidative stress because these metals serve as enzymatic cofactors in antioxidative defense mechanisms. The basic knowledge about trace metal requirements of Symbiodinium is lacking. Here we show that the requirement of Symbiodinium kawagutii for antioxidant-associated trace metals exhibits the following order: Fe > Cu/Zn/Mn > Ni. In growth media with Cu, Zn, Mn, and varying Fe concentrations, we observed that Cu, Zn, and Mn cellular quotas were inversely related to Fe concentrations. In the absence of Cu, Zn, and Mn, growth rates increased with increasing inorganic Fe concentrations up to 1250 pM, indicating the relatively high Fe requirement for Symbiodinium growth and potential functional complementarity of these metals. These results demonstrate the relative importance of trace metals to sustain Symbiodinium growth and a potential metal inter replacement strategy in Symbiodinium to ensure survival of coral reefs in an oligotrophic and stressful environment. PMID:26903964

  20. Arsenic and Associated Trace Metals in Texas Groundwater

    NASA Astrophysics Data System (ADS)

    Lee, L.; Herbert, B. E.

    2002-12-01

    The value of groundwater has increased substantially worldwide due to expanding human consumption. Both the quantity and quality of groundwater are important considerations when constructing policies on natural resource conservation. This study is focused on evaluating groundwater quality in the state of Texas. Historical data from the Texas Water Development Board and the National Uranium Resource Evaluation were collected into a GIS database for spatial and temporal analyses. Specific attentions were placed on arsenic and other trace metals in groundwater. Recent studies in the United States have focused on isolated incidences of high arsenic occurrence, ignoring possible connections between arsenic and other trace metals. Descriptive statistics revealed strong correlations in groundwater between arsenic and other oxyanions including vanadium, selenium and molybdenum. Arsenic and associated trace metals were clustered at three physiographic hotspots, the Southern High Plains, the Gulf Coastal Plains of Texas, and West Texas. A geologic survey showed that arsenic and other trace metals in Texas groundwater follow local geologic trends. Uranium deposits and associated mineralization were found to occur in the same physiographic locations. Uranium mineralization may be a significant natural source of arsenic and other trace metals in Texas groundwater. Recharge, evaporative concentration, and aquifer characteristics were also contributing factors to the occurrence of trace metals in Texas groundwater. Spatial statistics were used to delineate natural sources from anthropogenic inputs. Similarly, the natural background was estimated from the spatial distribution of trace metal observations in Texas groundwater.

  1. Laser-Induced Breakdown Spectroscopy of Trace Metals

    NASA Technical Reports Server (NTRS)

    Simons, Stephen (Technical Monitor); VanderWal, Randall L.; Ticich, Thomas M.; West, Joseph R., Jr.

    2004-01-01

    An alternative approach for laser-induced breakdown spectroscopy (LIBS) determination of trace metal determination in liquids is demonstrated. The limits of detection (LOD) for the technique ranged from 10 ppb to 10 ppm for 15 metals metals (Mg, Al, Si, Ca, Ti, Cr, Fe, Co, Ni, Cu, Zn, As, Cd, Hg, Pb) tested.

  2. Fate of biosolids trace metals in a dryland wheat agroecosystem

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biosolids land application for beneficial reuse applies varying amounts of trace metals to soils. Measuring plant-available or total soil metals is typically performed to ensure environmental protection, yet these techniques do not quantify which soil phases play important roles in terms of metal r...

  3. Trace metal enrichments in Lake Tanganyika sediments: Controls on trace metal burial in lacustrine systems

    NASA Astrophysics Data System (ADS)

    Poulson Brucker, Rebecca; McManus, James; Severmann, Silke; Owens, Jeremy; Lyons, Timothy W.

    2011-01-01

    We investigate the distributions of several key diagenetic reactants (C, S, Fe) and redox-sensitive trace metals (Mo, Cd, Re, U) in sediments from Lake Tanganyika, East Africa. This study includes modern sediments from a chemocline transect, which spans oxygenated shallow waters to sulfidic conditions at depth, as well as ancient sediments from a longer core (˜2 m) taken at ˜900 m water depth. Modern sediments from depths spanning ˜70-335 m are generally characterized by increasing enrichments of C, S, Mo, Cd, and U with increasing water depth but static Fe distributions. It appears that the sedimentary enrichments of these elements are, to varying degrees, influenced by a combination of organic carbon cycling and sulfur cycling. These modern lake characteristics contrast with a period of high total organic carbon (C org), total sulfur (S Tot), and trace metal concentrations observed in the 900 m core, a period which follows the most recent deglaciation (˜18-11 ky). This interval is followed abruptly by an interval (˜11-6 ky) that is characterized by lower C, S, U, and Mo. Consistent with other work we suspect that the low concentrations of S, Mo, and U may indicate a period of intense lake mixing, during which time the lake may have been less productive and less reducing as compared to the present. An alternative, but not mutually exclusive, hypothesis is that changes in the lake's chemical inventory, driven by significant hydrological changes, could be influencing the distribution of sedimentary trace elements through time.

  4. Separation of traces of metal ions from sodium matrices

    NASA Technical Reports Server (NTRS)

    Korkisch, J.; Orlandini, K. A.

    1969-01-01

    Method for isolating metal ion traces from sodium matrices consists of two extractions and an ion exchange step. Extraction is accomplished by using 2-thenoyltrifluoracetone and dithizone followed by cation exchange.

  5. Ecotoxicological risk assessment of trace metals in humid subtropical soil.

    PubMed

    Adhikari, Gopi; Bhattacharyya, Krishna G

    2015-11-01

    In this work, several physicochemical properties of sub-tropical soil (up to 20 cm depth) like water holding capacity, organic carbon content, cation exchange capacity, texture, pH, and electrical conductivity were determined along with the trace metals, Co, Cr, Cu, Mn, Ni, Pb and Zn, in order to evaluate inter-relations among the trace metals and the soil properties. The contribution of the trace metals to ecotoxicological risk was assessed using various tools. Cr, Cu, Mn and Zn contents were found to be lower than the world average, but Co, Ni, and Pb had higher contents. The trace metal concentrations were utilized to obtain the pollution index and the potential ecotoxicological aspects. The trace metals were shown to have come from similar origin and their retention in the soil was contributed by properties like organic carbon, cation exchange capacity, clay content and water holding capacity of the soil. The pollution index showed that the trace metals had the sequence of Pb (considerably polluted) > Co, Ni (moderately polluted) > Cr, Cu, Mn and Zn (unpolluted). The composite ecological risk index was the highest in agricultural land with irrigation and fertilizer use, and was the lowest in the forest land. PMID:26254205

  6. Influence of biochar amendments on marine sediment trace metal bioavailability

    NASA Astrophysics Data System (ADS)

    Gehrke, G. E.; Hsu-Kim, H.

    2014-12-01

    Biochar has become a desirable material for use in agricultural application to enhance soil quality and in-situ soil and sediment remediation to immobilize organic contaminants. We investigated the effects of biochar sediment amendments on the bioavailability of a suite of inorganic trace metals (Cr, Co, Ni, Cu, Zn, Pb) in contaminated sediments from multiple sites in Elizabeth River, VA. We incubated sediments in microcosms with a variety of water column redox and salinity conditions and compared sediments amended with two types of woody biochar to sediments amended with charcoal activated carbon and unamended sediments. We leached sediments in artificial gut fluid mimic of the benthic invertebrate Arenicola marina as a measure of bioavailability of the trace metals analyzed. In unamended anaerobic sediments, the gut fluid mimic leachable fraction of each trace metal is 1-4% of the total sediment concentration for each metal. Initial results indicate that in anaerobic microcosms, woody biochar sediment amendments (added to 5% dry wt) decrease the gut fluid mimic leachable fraction by 30-90% for all trace metals analyzed, and have comparable performance to charcoal activated carbon amendments. However, in microcosms without controlled redox conditions, woody biochar amendments increase the bioavailable fraction of Ni and Cu by up to 80%, while decreasing the bioavailable fraction of Co, Zn, and Pb by approximately 50%; charcoal activated carbon amendments decreased the bioavailability of all trace metals analyzed by approximately 20%. In microcosms without an overlying water column, biochar and activated carbon amendments had no significant effects on trace metal bioavailability. This research demonstrates that biochar can effectively decrease the bioavailability of trace metals in marine sediments, but its efficiency is metal-specific, and environmental conditions impact biochar performance.

  7. Hair concentration of essential trace elements in adult non-exposed Russian population.

    PubMed

    Skalny, Anatoly V; Skalnaya, Margarita G; Tinkov, Alexey A; Serebryansky, Eugeny P; Demidov, Vasily A; Lobanova, Yulia N; Grabeklis, Andrei R; Berezkina, Elena S; Gryazeva, Irina V; Skalny, Andrey A; Skalnaya, Oksana A; Zhivaev, Nikolay G; Nikonorov, Alexandr A

    2015-11-01

    Appropriate reference values of hair trace element content are required for correct interpretation of biomonitoring data. The primary objective of the current study was to estimate the reference values of selected essential trace elements in hair of adult Russian population. Involved in current investigation were 7256 occupationally non-exposed adults aged from 20 to 60 years and living in the European part of Russia. Occipital hair essential metal and metalloid (Co, Cr, Cu, Fe, Mn, Se, V, Zn) content was estimated using inductively coupled plasma mass spectrometry. The reference ranges were calculated in accordance with the International Union of Pure and Applied Chemistry (IUPAC) recommendations. Women were characterized by 55, 18, 58, and 7% higher values of hair Co, Cu, Mn, and Zn content as compared to the values observed in men. At the same time, hair Cr, Fe, Se, and V concentration in men significantly exceeded the respective female values by 65, 13, 20, and 56%. Consequently, the reference ranges of essential hair trace elements content should be separately calculated for both men and women. The obtained reference ranges for hair Co, Cr, Cu, Fe, Mn, Se, V, and Zn in men were 0.11-0.67, 0.007-0.045, 10.4-22.6, 11.1-40.5, 0.24-1.05, 0.089-0.480, 0.014-0.083, and 125.7-262.8 μg/g, respectively. The respective values estimated for women were 0.06-0.40, 0.011-0.085, 12.1-44.5, 8.9-25.6, 0.32-2.05, 0.094-0.504, 0.010-0.056, and 140.0-315.1 μg/g. The reference ranges for hair Co (0.07-0.50), Cr (0.009-0.073), Cu (11.8-29.2), Fe (9.6-31.5), Mn (0.29-1.76), Se (0.093-0.482), V (0.011-0.069), and Zn (134.7-301.9) content (μg/g) in the general cohort were also calculated. PMID:26446131

  8. Trace metal accumulation in carbonate biominerals of the Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Demina, L. L.; Oskina, N. S.; Galkin, S. V.

    2016-01-01

    New data on trace metal (As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb) distribution in carbonate biominerals formed in geochemically different oceanic environments are discussed. Calcite shells of shelf and deepwater hydrothermal vent mussels as well as planktic foraminifers and pteropods from the central Atlantic Ocean have been studied. The variability in concentrations of most trace elements between different groups of calcifying organisms are usually within one order of magnitude, except for Fe and Mn, the elevated contents of which in microfossils are caused by post-sedimentation interaction. Different groups of calcifying organisms demonstrate a biogeochemical uniformity in trace metal accumulation during the biomineralization processes.

  9. Physiology and metabolism of essential trace elements: an outline.

    PubMed

    Aggett, P J

    1985-08-01

    Man depends on at least nine trace elements--iron, zinc, copper, manganese, iodine, chromium, selenium, molybdenum and cobalt--for optimum metabolic function. These elements serve a variety of functions including catalytic, structural and regulatory activities in which they interact with macromolecules such as enzymes, pro-hormones, pre-secretory granules and biological membranes. These micronutrients are involved, therefore, in all major metabolic pathways at levels which are so fundamental that the features of deficiency of many of them are protean and non-specific. In considering the metabolism of the elements themselves, they fall into two groups: those which exist normally as cations and those present as anions. The latter group are absorbed relatively easily and whole-body homeostasis is mediated mainly by renal excretion. The cations need specific pathways for absorption and their homeostasis is effected by gastrointestinal and biliary secretion. Some elements are absorbed more efficiently as organic complexes. The net achievement of the metabolic pathways for each element is to deliver it to its functional site(s) by exploiting its physicochemical characteristics to avoid interactions with other inorganic nutrients. PMID:3905079

  10. The Little Penguin (Eudyptula minor) as an indicator of coastal trace metal pollution.

    PubMed

    Finger, Annett; Lavers, Jennifer L; Dann, Peter; Nugegoda, Dayanthi; Orbell, John D; Robertson, Bruce; Scarpaci, Carol

    2015-10-01

    Monitoring trace metal and metalloid concentrations in marine animals is important for their conservation and could also reliably reflect pollution levels in their marine ecosystems. Concentrations vary across tissue types, with implications for reliable monitoring. We sampled blood and moulted feathers of the Little Penguin (Eudyptula minor) from three distinct colonies, which are subject to varying levels of anthropogenic impact. Non-essential trace metal and metalloid concentrations in Little Penguins were clearly linked to the level of industrialisation adjacent to the respective foraging zones. This trend was more distinct in blood than in moulted feathers, although we found a clear correlation between blood and feathers for mercury, lead and iron. This study represents the first reported examination of trace metals and metalloids in the blood of any penguin species and demonstrates that this high trophic feeder is an effective bioindicator of coastal pollution. PMID:26160534

  11. A primer on trace metal-sediment chemistry

    USGS Publications Warehouse

    Horowitz, Arthur J.

    1985-01-01

    In most aquatic systems, concentrations of trace metals in suspended sediment and the top few centimeters of bottom sediment are far greater than concentrations of trace metals dissolved in the water column. Consequently, the distribution, transport, and availability of these constituents can not be intelligently evaluated, nor can their environmental impact be determined or predicted solely through the sampling and analysis of dissolved phases. This Primer is designed to acquaint the reader with the basic principles that govern the concentration and distribution of trace metals associated with bottom and suspended sediments. The sampling and analysis of suspended and bottom sediments are very important for monitoring studies, not only because trace metal concentrations associated with them are orders of magnitude higher than in the dissolved phase, but also because of several other factors. Riverine transport of trace metals is dominated by sediment. In addition, bottom sediments serve as a source for suspended sediment and can provide a historical record of chemical conditions. This record will help establish area baseline metal levels against which existing conditions can be compared. Many physical and chemical factors affect a sediment's capacity to collect and concentrate trace metals. The physical factors include grain size, surface area, surface charge, cation exchange capacity, composition, and so forth. Increases in metal concentrations are strongly correlated with decreasing grain size and increasing surface area, surface charge, cation exchange capacity, and increasing concentrations of iron and manganese oxides, organic matter, and clay minerals. Chemical factors are equally important, especially for differentiating between samples having similar bulk chemistries and for inferring or predicting environmental availability. Chemical factors entail phase associations (with such sedimentary components as interstitial water, sulfides, carbonates, and organic

  12. Control of Trace Metal Emissions During Coal Combustion

    SciTech Connect

    Thomas C. Ho

    1996-10-01

    Emissions of toxic trace metals in the form of metal fumes or submicron particulate from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDS) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor.

  13. Control of Trace Metal Emissions During Coal Combustion

    SciTech Connect

    Thomas C. Ho

    1997-10-01

    Emissions of toxic trace metals in the form of metal fumes or submicron particulates from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDs) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor. The project was started on July 1, 1994 and this is the thirteenth quarterly technical progress report. Specifically, the following progress has been made during this performance period from July 1, 1997 through September 30, 1997.

  14. Control of Trace Metal Emissions During Coal Combustion

    SciTech Connect

    Thomas C. Ho

    1997-01-01

    Emissions of toxic trace metals in the form of metal fumes or submicron particulates from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDs) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor.

  15. Control of Trace Metal Emissions During Coal Combustion

    SciTech Connect

    Thomas C. Ho

    1997-07-01

    Emissions of toxic trace metals in the form of metal fumes or submicron particulates from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDs) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor.

  16. Control of Trace Metal Emissions During Coal Combustion

    SciTech Connect

    Thomas C. Ho

    1997-04-01

    Emissions of toxic trace metals in the form of metal fumes or submicron particulates from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDs) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor.

  17. Sedimentary input of trace metals from the Chukchi Shelf

    NASA Astrophysics Data System (ADS)

    Aguilar-Islas, A. M.; Seguré, M.; Rember, R.; Nishino, S.

    2014-12-01

    The distribution of trace metals in the Arctic Ocean has implications for their global cycles, yet until recently few trace metal observations were available from this rapidly changing ocean. Profiles of dissolved Fe from recent Japanese field efforts in the Western Canada Basin (2008, 2010) indicate the broad Chukchi Shelf as a source of Fe to the halocline of the Western Canada Basin. Here we present dissolved and particulate data for crustal (Al, Mn, Fe) and non-crustal elements (Co, Cu, Zn) from the productive Chukchi Sea to characterize the sedimentary input of these metals to shelf waters contributing to the halocline layer of the Canada Basin. Water column profiles were collected in late summer 2013 onboard the R/V Mirai at 10 stations from the Bering Strait to the slope, and at a time-series (10 days) station located over the outer shelf. A narrow and variable (5-10 m) benthic boundary layer was sampled at the time-series station with highly elevated dissolved and suspended particulate metal concentrations. High metal concentrations were also observed in the subsurface at a station over Barrow Canyon where mixing is enhanced. Reactivity of suspended particulate metals was determined by the leachable vs. refractory fractions. Metal concentrations were determined by ICP-MS. Trace metal transport from the shelf to the interior will be discussed in context with shelf mechanisms contributing to this export, and to expected future changes in the Arctic Ocean.

  18. Equilibrium modeling of trace metal transport from Duluth complex rockpile

    SciTech Connect

    Kelsey, P.D.; Klusman, R.W.; Lapakko, K.

    1996-12-31

    Geochemical modeling was used to predict weathering processes and the formation of trace metal-adsorbing secondary phases in a waste rock stockpile containing Cu-Ni ore mined from the Duluth Complex, MN. Amorphous ferric hydroxide was identified as a secondary phase within the pile, from observation and geochemical modeling of the weathering process. Due to the high content of cobalt, copper, nickel, and zinc in the primary minerals of the waste rock and in the effluent, it was hypothesized that the predicted and observed precipitant ferric hydroxide would adsorb small quantities of these trace metals. This was verified using sequential extractions and simulated using adsorption geochemical modeling. It was concluded that the trace metals were adsorbed in small quantities, and adsorption onto the amorphous ferric hydroxide was in decreasing order of Cu > Ni > Zn > Co. The low degree of adsorption was due to low pH water and competition for adsorption sites with other ions in solution.

  19. Essential and toxic trace element concentrations in different commercial veal cuts in Spain.

    PubMed

    López-Alonso, M; Miranda, M; Benedito, J L; Pereira, V; García-Vaquero, M

    2016-11-01

    The aim of this study was to evaluate essential and toxic element concentration of ten commercially available veal cuts, together with diaphragm, cardiac muscle and liver tissue from 10 animals of "Galician Supreme Veal". Essential trace elements (Co, Cr, Cu, Fe, Mn, Mo, Ni, Se and Zn) and toxic elements (As, Cd, Hg and Pb) were determined by ICP-MS. Essential trace element concentrations ranged from 0.002-55.64mg/kg between muscles. Toxic element concentrations were very low, and high numbers of samples showed unquantifiable residues of Cd and Pb. Veal cuts including muscles with a high proportion of oxidative slow-twitch fibers (diaphragm and cardiac muscle) showed significantly higher essential trace element concentrations, the lower concentrations being found in veal cuts including glycolytic fast-twitch fibers (eye round). Our results suggest that essential and toxic trace element concentration could be used as a new meat quality parameter, or to add further value to certain products (i.e. livestock reared on extensive systems with high physical activity). PMID:27261950

  20. Clean Air Act requirements for trace-metals information

    SciTech Connect

    Pahl, D.; Hunt, W.; Evans, G.

    1992-01-01

    The Clean Air Act Amendments of 1990 have expanded the requirements for trace metal and air toxics information in urban areas and added new requirements for this information in rural areas and ecosystems. Specific provisions germane to trace metals and other air toxics compounds are found in Title III, Section 112 and in Title IX, Section 901. In response to these provisions, the United States Environmental Protection Agency (EPA) plans to conduct research in atmospheric monitoring networks in urban areas, in the Great Lakes watershed, and in regional components of a national Clean Air Act status and trends network.

  1. Biomonitor of Environmental Stress: Coral Trace Metal Analysis

    NASA Astrophysics Data System (ADS)

    Grumet, N.; Hughen, K.

    2006-12-01

    Tropical reef corals are extremely sensitive to changes in environmental conditions and, as a result of environmental degradation and global climate change, coral reefs around the globe are severely threatened. Increased human population and development in tropical regions is leading to higher turbidity and silt loading from terrestrial runoff, increased pesticides and nutrients from agricultural land-use and sewage, and the release of toxic trace metals to coastal waters from industrial pollution. The uptake of these metals and nutrients within the coral skeletal aragonite is a sensitive biomonitor of environmental stresses on coral health. We analyzed 18 trace metals from the surface of coral skeletons collected in Bermuda, Indonesia and Belize to assess a range of threats to coral reef health - including climate change, agricultural runoff and pesticides, and coastal development and tourism. This surface sample network also includes samples representing 4 different coral species. Trace metal analysis was performed on an inductively coupled plasma mass spectrometer (ICP-MS) to a high degree of accuracy and precision at extremely low (ppb) concentrations using a protocol we developed for samples less than 2 mg. Proper cleaning techniques were employed to minimize blank level concentrations for ultra-trace metal ICP-MS solution analysis. However, Zn/Ca and Ni/Ca concentrations remain below analytical detection limits. Initial results indicate that sea surface temperature proxies (e.g., Sr/Ca, B/Ca and Mg/Ca) display similar ratios between the different sites, whereas those metals associated with anthropogenic activities, such as Co, Pb and Cu, are site-specific and are linked to individual environmental stressors. Results from this study will be applied to down core trace metal records in the future. In doing so, we aim to understand the impacts of compounding environmental stresses on coral health, and to identify regional threshold values beyond which corals

  2. Trace metal contamination study on scalp hair of occupationally exposed workers

    SciTech Connect

    Ashraf, W.; Jaffar, M. ); Mohammad, D. )

    1994-10-01

    Scalp hair is a metabolic end product that incorporates metals into its structure during the growth process. The levels of trace elements in the hair are considered to be influenced in particular by food, air and occupational exposure, and in general by race, age, sex, metabolism, hygienic condition and geographical location of individuals. Recently, trace metal content of human hair has been explored as a tool for monitoring the impact of environmental pollution on the inhabitants of a community. In this respect, the endogenous and exogenous contents of metals in hair are understood to play important role towards exposure assessment. The exogenous metal content of hair reflects exposure to the occupational, domestic and recreational environments, provided the donor is not suffering from heavy metal poisoning and depressed endogenous levels arising from dietary deficiencies. Keeping this in view, the exogenous and endogenous metal contents of scalp hair of occupationally exposed workers from various workshops were determined in the present study, both in unwashed and washed hair samples to assess the extent of metal contamination. All donors, within the age group of 6-45 years, were full-time workers of various autoworkshops situated in the densely populated and industrialized city of Lahore. ICP atomic emission and atomic absorption spectrophotometric methods were used for determining the levels of five non-essential and three essential elements in the scalp hair. 20 refs., 6 tabs.

  3. Nutritional Aspects of Essential Trace Elements in Oral Health and Disease: An Extensive Review

    PubMed Central

    Hussain, Mohsina

    2016-01-01

    Human body requires certain essential elements in small quantities and their absence or excess may result in severe malfunctioning of the body and even death in extreme cases because these essential trace elements directly influence the metabolic and physiologic processes of the organism. Rapid urbanization and economic development have resulted in drastic changes in diets with developing preference towards refined diet and nutritionally deprived junk food. Poor nutrition can lead to reduced immunity, augmented vulnerability to various oral and systemic diseases, impaired physical and mental growth, and reduced efficiency. Diet and nutrition affect oral health in a variety of ways with influence on craniofacial development and growth and maintenance of dental and oral soft tissues. Oral potentially malignant disorders (OPMD) are treated with antioxidants containing essential trace elements like selenium but even increased dietary intake of trace elements like copper could lead to oral submucous fibrosis. The deficiency or excess of other trace elements like iodine, iron, zinc, and so forth has a profound effect on the body and such conditions are often diagnosed through their early oral manifestations. This review appraises the biological functions of significant trace elements and their role in preservation of oral health and progression of various oral diseases. PMID:27433374

  4. Nutritional Aspects of Essential Trace Elements in Oral Health and Disease: An Extensive Review.

    PubMed

    Bhattacharya, Preeti Tomar; Misra, Satya Ranjan; Hussain, Mohsina

    2016-01-01

    Human body requires certain essential elements in small quantities and their absence or excess may result in severe malfunctioning of the body and even death in extreme cases because these essential trace elements directly influence the metabolic and physiologic processes of the organism. Rapid urbanization and economic development have resulted in drastic changes in diets with developing preference towards refined diet and nutritionally deprived junk food. Poor nutrition can lead to reduced immunity, augmented vulnerability to various oral and systemic diseases, impaired physical and mental growth, and reduced efficiency. Diet and nutrition affect oral health in a variety of ways with influence on craniofacial development and growth and maintenance of dental and oral soft tissues. Oral potentially malignant disorders (OPMD) are treated with antioxidants containing essential trace elements like selenium but even increased dietary intake of trace elements like copper could lead to oral submucous fibrosis. The deficiency or excess of other trace elements like iodine, iron, zinc, and so forth has a profound effect on the body and such conditions are often diagnosed through their early oral manifestations. This review appraises the biological functions of significant trace elements and their role in preservation of oral health and progression of various oral diseases. PMID:27433374

  5. Elucidating the Composition and Distribution of Trace Metals in Corals

    NASA Astrophysics Data System (ADS)

    Farfan, G.; Webb, S. M.; Apprill, A.; Hansel, C. M.

    2014-12-01

    Coral reefs host a plethora of marine life and thereby provide a wealth of aesthetic and economic benefits to coastal countries. Anthropogenic influences, including local coastal water contamination, however threaten the health of these delicate ecosystems. Metal incorporation into carbonate minerals, the backbone of coral reefs, is known to have a large yet variable impact on carbonate structure and solubility. Yet, trace metal influences on the structure, porosity, composition, and solubility of coral skeletons is largely unknown. Here, we coupled synchrotron-based micro-X-ray fluorescence (u-XRF) mapping and X-ray absorption near edge structure (XANES) spectroscopy with micro-X-ray diffraction (XRD) to explore the distribution and speciation of trace metals associated with corals and their impact on the carbonate structure of corals obtained from reefs varying in anthropogenic influence - Florida Keys, FL USA and the Federated States of Micronesia. Iron and copper were the most abundant metals in the biological tissue, while in some areas zinc was observed in the tissue, overlapping with the skeleton. Trace metals were not detectable in the aragonite skeletons; in fact, the distributions of Ca and Fe were anti-correlated. XANES spectra show that the iron is primarily Fe(III), likely as the poorly crystalline iron oxide ferrihydrite structure or trapped within ferretin proteins. The same trace metals were observed in corals of different species and from different environments. This in situ investigation corroborates previous studies that corals tend to incorporate iron into the biological components but not into the aragonite skeleton. Given the dominant partitioning of metals within the biological tissue rather than the coral skeleton, the specific carbon molecules responsible for metal attenuation and their fate under changing geochemical conditions and following coral death require exploration.

  6. Pyritization of trace metals in anoxic marine sediments

    NASA Astrophysics Data System (ADS)

    Huerta-Diaz, Miguel A.; Morse, John W.

    1992-07-01

    The pyritization of reactive trace elements in different anoxic marine sediments was investigated to determine the importance of factors such as ∑H 2S, reactive-Fe, pyrite content and salinity in controlling this process. The areas studied included anoxic-sulfidic sediments (Baffin Bay, a hypersaline coastal lagoon from Texas and Green Canyon, a hemipelagic oil seepage area), anoxic-nonsulfidic sediments with high sedimentation rates (Atchafalaya Bay-Mississippi Delta system), hemipelagic anoxic-nonsulfidic sediments with low sedimentation rates (Gulf of Mexico shelf and slope and Orca Basin, an euxinic hypersaline basin) and organic-rich marsh sediments (Atchafalaya Bay). Results indicate that the degree of trace metal pyritization (DTMP) of all trace metals, except Cd, increased with increasing degree of pyritization (DOP), irrespective of the type of sedimentary environment involved. However, for As, Hg and Mo, the DTMP/DOP values were generally above the 1:1 ratio line, whereas the transition metals Co, Cu, Mn and Ni displayed a close to linear increase in DTMP with DOP and moderate incorporation into pyrite. Chromium and the class B metals Pb and Zn were also gradually incorporated into the pyrite phase but without reaching the DTMP levels exhibited by the transition metals. Cadmium was not incorporated to a significant extent. These results are consistent with the chemical attributes of these different classes of trace elements. Availability of dissolved trace metals and organic matter content are apparently important factors controlling the incorporation of Co, Cr, Cu and Ni into pyrite in anoxicsulfidic (Fe-poor and H 2S-rich) environments.

  7. Metal fractionation in sediments as a tool for assessing the availability of trace metals: The case of Apipucos Reservoir

    NASA Astrophysics Data System (ADS)

    Lima, V. L.; Souza, V. L. B.; Nascimento, R. K.; Santos, P. N. C.; Almeida, M. G. O.; Hazin, C. A.

    2014-02-01

    The worldwide concern about trace metal pollution has been increasing in recent years due to the increase in anthropogenic trace metal inputs to the various ecosystems. The quantification of the chemical species of metals in sediments is essential for estimating the bioavailability of the metals in the environment. The objective of this study was to characterize the present level of metal pollution in the Apipucos Reservoir, Brazil, and determine its degree of toxicity to plants and animals. For this purpose, sediment cores were collected and its metal content (Zn, Pb, Cd, Co, Mn, Fe, Cu) was analyzed by atomic absorption spectrometry after sequential extraction. The results showed that there is more Fe and Mn than other metals (Fe>Mn>Pb>Zn>Cu). Besides, the concentrations of Fe and Mn are very high in the exchangeable and available phases, which are mobile and available fractions in sediments. The results also indicate that Fe, Mn and Cu could be mobilized under oxidizing conditions. Lead was found mainly in the reducible phase whereas Zn was found on available and reducible phases. Cobalt and Cadmium, although included in the set of metals analyzed, were not found in the sampled sediments. Sediment dating showed that the first sedimentary layers are about 30 years old.

  8. Nanomolar Trace Metal Analysis of Copper at Gold Microband Arrays

    NASA Astrophysics Data System (ADS)

    Wahl, A.; Dawson, K.; Sassiat, N.; Quinn, A. J.; O'Riordan, A.

    2011-08-01

    This paper describes the fabrication and electrochemical characterization of gold microband electrode arrays designated as a highly sensitive sensor for trace metal detection of copper in drinking water samples. Gold microband electrodes have been routinely fabricated by standard photolithographic methods. Electrochemical characterization were conducted in 0.1 M H2SO4 and found to display characteristic gold oxide formation and reduction peaks. The advantages of gold microband electrodes as trace metal sensors over currently used methods have been investigated by employing under potential deposition anodic stripping voltammetry (UPD-ASV) in Cu2+ nanomolar concentrations. Linear correlations were observed for increasing Cu2+ concentrations from which the concentration of an unknown sample of drinking water was estimated. The results obtained for the estimation of the unknown trace copper concentration in drinking was in good agreement with expected values.

  9. Trace metals and cancer: The case of neuroblastoma

    NASA Astrophysics Data System (ADS)

    Gouget, B.; Sergeant, C.; Llabador, Y.; Devès, G.; Vesvres, M. H.; Simonoff, M.; Bénard, J.

    2001-07-01

    N- myc oncogene amplification is one of the most established prognostic factors in neuroblastoma (NB), a young children solid tumor. Amounts of ferritin, an iron storage protein, are abnormally increased in serum of patients with advanced stage disease. N- myc amplified NB cells can synthesize zinc metalloenzymes allowing tumor invasion and metastases formation. The aim of this study was to find a relationship between N- myc amplification and trace metals in human neuroblasts. Coupling PIXE and RBS techniques, nuclear microprobe allowed to analyze elemental distributions and to determine trace metal concentrations within cultured neuroblasts characterized by various degrees of N- myc amplification. They were compared to trace metal distributions and concentrations in tumor xenograft models of human NB, after injection of cells from the same lines in athymic nude mice. Our data allowed to establish a relation between trace metal contents and mechanisms of NB oncogenesis, amplified cell lines representing more aggressive phenotypes of the disease. They should be confirmed by analysis of cultured neuroblasts and tumors issued from a non-amplified cell line transfected with the N- myc oncogene.

  10. Trace metal enrichment in agricultural soils of Jianghan Plain

    NASA Astrophysics Data System (ADS)

    Zhao, R.; Ying, S.; Daniel, J. N.; Bu, J.; Gan, Y.; Wang, Y.; Schaefer, M.; Fendorf, S. E.

    2014-12-01

    Coal consumption in China is increasing annually due to constantly rising energy demand. As a result, a massive amount of coal combustion byproducts, particularly in the form of fly ash, are expelled from power plants and distributed through atmospheric transport. The fly ash is eventually deposited on to land, potentially contaminating agricultural soils. Coal fly ash contains high concentration of a suite of toxic trace metals including lead, chromium, and arsenic. In this study, we surveyed the concentration of trace metals in agricultural soils at 131 sites within a 20 km radius of Yangluo Power Plant, a 2400 MW plant within the highly populated Jianghan Plain of Central China. Using X-ray fluorecence (XRF) spectrometry, the total concentration of trace metals in homogenized surface and subsurface soil samples were measured to calculate the corresponding enrichment factor at each site. Our initial findings demonstrate that Pb is enriched in a majority of sites, independent of land use, whereas As and Cr are generally not enriched in this region. Further studies using Pb isotopes as a source-tracing tool will help determine the Pb pollution's origin. Ultimately, the results of this study may inform whether crops grown within the Jianghan Plain have the potential of being contaminated by metals emitted from coal power plants.

  11. Unexpected Consequences: Gold Mining in Peru and Trace Metal Mobilization

    NASA Astrophysics Data System (ADS)

    Wang, R. Z.; Pinedo-Gonzalez, P.; Clark, K. E.; West, A. J.

    2014-12-01

    Artisanal miners in the Peruvian Amazon, especially in the Madre de Dios region, are targeting fluvial deposits along riverbanks as part of a modern-day gold rush. These miners often use mercury, causing Hg pollution and ecological damage. Research on the environmental consequences of these mines has focused primarily on the fate of Hg, and to date little work has considered whether mining river sediments affects the release and cycling of other trace metals. This project measures trace metal concentrations in soil and vegetation samples developed on fluvial sediments at one mine site and two non-mine (control) sites across gradients in natural plant succession and riverbank composition. Some metals, including Pb and Mo, showed leachable metal concentrations (determined using EPA Method 2050B and ICP-MS analysis) that were lower in mine site soils than control site soils, but higher in mine site vegetation than control site vegetation. These results held across all gradients in natural plant succession and soil composition. This suggests that metals may be preferentially mobilized from the soil and taken up by surrounding vegetation as a result of mining activities. Soils were also treated with a sequential leach to separate metals that are exchangeable, bound to carbonates, bound to Fe and Mn oxides, bound to organic matter and in the residual phase. Initial data shows that trace metal concentrations are generally lower in all phases from mine soils vs. control soils, across all gradients in natural plant succession and soil composition. Trace metal mobilization due to mining is facilitated by changing pH or redox conditions - e.g., by exposing buried minerals to water and oxygen. Fluvial sediments at these studied sites were already exposed during their erosion and transport, but anoxic conditions following deposition may allow a build-up of metals that are mobilized once sediments are re-worked by mining. It is also possible that Hg affects the mobility of other

  12. Trace metal levels in sediments of Pearl Harbor (Hawaii)

    SciTech Connect

    Ashwood, T.L.; Olsen, C.R.; Larsen, I.L.; Tamura, T.

    1986-09-01

    This study was conducted to measure the distribution of lead and other trace metals in the sediments of Pearl Harbon (Hawaii) to determine whether paint chips from vessels of the US Navy's Inactive Fleet have affected the environmental quality of Middle Loch. Sediment cores (ranging from 0.5 to 3.0 m long) were collected from Middle Loch near the Naval Inactive Ships Maintenance Facility and in an area of West Loch that is relatively isolated and unaffected by naval operations. Concentrations of copper, lead, and zinc averaged 180 ..mu..g/g, 49 ..mu..g/g, and 272 ..mu..g/g, respectively, in recent Middle Loch sediments. These concentrations are significantly higher than those in either historical Middle Loch sediments or recent West Loch sediments. However, except for lead, the concentrations in recent Middle Loch sediments are similar to those of older Middle Loch sediments, which indicates that the increase in trace metal contamination began before the onset of Inactive Fleet operations (about 1946). Increased trace metal levels in recent Middle Loch sediments might be expected to result from two potential sources: (1) sewage discharges and (2) paint from inactive vessels. Since paint contains elevated levels of lead and zinc but little copper, the elevated copper levels in Middle Loch sediments tend to implicate sewage as the source of trace metal contamination. Moreover, the lead:zinc ratio of recent Middle Loch sediments (0.18:1) is a factor of 10 lower than that measured in paint (2.1:1), and the Middle Loch lead:zinc ratio is not significantly greater than that measured in recent West Loch sediments (0.21:1). Hence, we suggest that sewage rather than paint is the major source of trace metal contamination of Middle Loch. This is consistent with the findings of a previous study by US navy personnel.

  13. CONTROL OF TRACE METAL EMISSIONS DURING COAL COMBUSTION

    SciTech Connect

    THOMAS C. HO

    1998-02-18

    Emissions of toxic trace metals in the form of metal fumes or submicron particulates from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDs) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor. This final technical report details the work performed, the conclusions obtained, and the accomplishments achieved over the project performance period from July 1, 1994 through December 31, 1997. Specifically, this report consists of the following five chapters: Chapter 1. Executive Summary; Chapter 2. Metal Capture by Various Sorbents; Chapter 3. Simultaneous Metal and Sulfur Capture; Chapter 4. Sorption and Desorption of Mercury on Sorbents; and Chapter 5. Project Conclusions. In summary, the metals involved in the project were arsenic, cadmium, chromium, lead, mercury and selenium and the sorbents tested included bauxite, zeolite and calcined limestone. The three sorbents have been found to have various degree of metal capture capability on arsenic, cadmium, chromium and lead

  14. Trace metal source terms in carbon sequestration environments.

    PubMed

    Karamalidis, Athanasios K; Torres, Sharon G; Hakala, J Alexandra; Shao, Hongbo; Cantrell, Kirk J; Carroll, Susan

    2013-01-01

    Carbon dioxide sequestration in deep saline and depleted oil geologic formations is feasible and promising; however, possible CO(2) or CO(2)-saturated brine leakage to overlying aquifers may pose environmental and health impacts. The purpose of this study was to experimentally define a range of concentrations that can be used as the trace element source term for reservoirs and leakage pathways in risk simulations. Storage source terms for trace metals are needed to evaluate the impact of brines leaking into overlying drinking water aquifers. The trace metal release was measured from cements and sandstones, shales, carbonates, evaporites, and basalts from the Frio, In Salah, Illinois Basin, Decatur, Lower Tuscaloosa, Weyburn-Midale, Bass Islands, and Grand Ronde carbon sequestration geologic formations. Trace metal dissolution was tracked by measuring solution concentrations over time under conditions (e.g., pressures, temperatures, and initial brine compositions) specific to the sequestration projects. Existing metrics for maximum contaminant levels (MCLs) for drinking water as defined by the U.S. Environmental Protection Agency (U.S. EPA) were used to categorize the relative significance of metal concentration changes in storage environments because of the presence of CO(2). Results indicate that Cr and Pb released from sandstone reservoir and shale cap rocks exceed the MCLs by an order of magnitude, while Cd and Cu were at or below drinking water thresholds. In carbonate reservoirs As exceeds the MCLs by an order of magnitude, while Cd, Cu, and Pb were at or below drinking water standards. Results from this study can be used as a reasonable estimate of the trace element source term for reservoirs and leakage pathways in risk simulations to further evaluate the impact of leakage on groundwater quality. PMID:23215015

  15. Trace Metal Source Terms in Carbon Sequestration Environments

    SciTech Connect

    Karamalidis, Athanasios; Torres, Sharon G.; Hakala, Jacqueline A.; Shao, Hongbo; Cantrell, Kirk J.; Carroll, Susan A.

    2013-01-01

    ABSTRACT: Carbon dioxide sequestration in deep saline and depleted oil geologic formations is feasible and promising; however, possible CO2 or CO2-saturated brine leakage to overlying aquifers may pose environmental and health impacts. The purpose of this study was to experimentally define to provide a range of concentrations that can be used as the trace element source term for reservoirs and leakage pathways in risk simulations. Storage source terms for trace metals are needed to evaluate the impact of brines leaking into overlying drinking water aquifers. The trace metal release was measured from cements and sandstones, shales, carbonates, evaporites, and basalts from the Frio, In Salah, Illinois Basin, Decatur, Lower Tuscaloosa, Weyburn-Midale, Bass Islands, and Grand Ronde carbon sequestration geologic formations. Trace metal dissolution was tracked by measuring solution concentrations over time under conditions (e.g., pressures, temperatures, and initial brine compositions) specific to the sequestration projects. Existing metrics for maximum contaminant levels (MCLs) for drinking water as defined by the U.S. Environmental Protection Agency (U.S. EPA) were used to categorize the relative significance of metal concentration changes in storage environments because of the presence of CO2. Results indicate that Cr and Pb released from sandstone reservoir and shale cap rocks exceed the MCLs byan order of magnitude, while Cd and Cu were at or below drinking water thresholds. In carbonate reservoirs As exceeds the MCLs by an order of magnitude, while Cd, Cu, and Pb were at or below drinking water standards. Results from this study can be used as a reasonable estimate of the trace element source term for reservoirs and leakage pathways in risk simulations to further evaluate the impact of leakage on groundwater quality.

  16. Trace metal mapping by laser-induced breakdown spectroscopy

    SciTech Connect

    Kaiser, Jozef; Novotny, Dr. Karel; Hrdlicka, A; Malina, R; Hartl, M; Kizek, R; Adam, V

    2012-01-01

    Abstract: Laser-Induced Breakdown Spectroscopy (LIBS) is a sensitive optical technique capable of fast multi-elemental analysis of solid, gaseous and liquid samples. The potential applications of lasers for spectrochemical analysis were developed shortly after its invention; however the massive development of LIBS is connected with the availability of powerful pulsed laser sources. Since the late 80s of 20th century LIBS dominated the analytical atomic spectroscopy scene and its application are developed continuously. Here we review the utilization of LIBS for trace elements mapping in different matrices. The main emphasis is on trace metal mapping in biological samples.

  17. On nutrients and trace metals: Effects from Enhanced Weathering

    NASA Astrophysics Data System (ADS)

    Amann, T.; Hartmann, J.

    2015-12-01

    The application of rock flour on suitable land ("Enhanced Weathering") is one proposed strategy to reduce the increase of atmospheric CO2 concentrations. At the same time it is an old and established method to add fertiliser and influence soil properties. Investigations of this method focused on the impact on the carbonate system, as well as on engineering aspects of a large-scale application, but potential side effects were never discussed quantitatively. We analysed about 120,000 geochemically characterised volcanic rock samples from the literature. Applying basic statistics, theoretical release rates of nutrients and potential contaminants by Enhanced Weathering were evaluated for typical rock types. Applied rock material can contain significant amounts of essential or beneficial nutrients (potassium, phosphorus, micronutrients). Their release can partly cover the demand of major crops like wheat, rice or corn, thereby increasing crop yield on degraded soils. However, the concentrations of considered elements are variable within a specific rock type, depending on the geological setting. High heavy metal concentrations are found in (ultra-) basic rocks, the class with the highest CO2 drawdown potential. More acidic rocks contain less or no critical amounts, but sequester less CO2. Findings show that the rock selection determines the capability to supply significant amounts of nutrients, which could partly substitute industrial mineral fertiliser usage. At the same time, the release of harmful trace element has to be considered. Through careful selection of regionally available rocks, benefits could be maximised and drawbacks reduced. The deployment of Enhanced Weathering to sequester CO2 and to ameliorate soils necessitates an ecosystem management, considering the release and fate of weathered elements in plants, soils and water. Cropland with degraded soils would benefit while having a net negative CO2 effect, while other carbon dioxide removal strategies, like

  18. Monitoring of trace metals in coastal sediments around Korean Peninsula.

    PubMed

    Hwang, Dong-Woon; Kim, Seong-Gil; Choi, Minkyu; Lee, In-Seok; Kim, Seong-Soo; Choi, Hee-Gu

    2016-01-15

    Spatial distributions and temporal variations of trace metals in Korean coastal sediments were investigated by determining seven metals (As, Cd, Cr, Cu, Hg, Pb, and Zn) in sediment collected from 71 stations between 2004 and 2010 (n=491). High metal concentrations were found in the southeastern coast, where there are many cities and industrial complexes, indicating that metal concentrations in Korean coastal sediment are significantly influenced by human activities associated with urbanization and industrialization. However, metal concentrations in sediment did not markedly vary temporally, which was because the coast is managed sustainably and because of the characteristics of the sediment environments. Based on the sediment quality guidelines and geoaccumulation index, Korean coastal sediments are practically unpolluted with Cd, Cr, Cu, Hg, Pb and Zn but moderately polluted with As. More intensive monitoring is required to determine the potential As sources and to understand the As geochemical cycles in Korean coastal sediments. PMID:26639653

  19. BIOLOGICAL MONITORING OF TOXIC TRACE METALS. VOLUME 1. BIOLOGICAL MONITORING AND SURVEILLANCE

    EPA Science Inventory

    The needs and priorities in using biological accumulator organisms for monitoring toxic trace metals in plants and animals are analyzed. The toxic trace metals selected for study are antimony, arsenic, beryllium, boron, cadmium, chromium, cobalt, copper, lead, mercury, nickel, se...

  20. Trace metals in edible tissues of livestock and poultry

    SciTech Connect

    Coleman, M.E.; Elder, R.S.; Basu, P.; Koppenaal, G.P.

    1992-07-01

    Data from a random-sampling study are presented for trace metals in edible tissues of livestock (bovine including bull, steer, cow heifer, calf; ovine including bull, steer, cow, heifer, calf; ovine including mature sheep and lambs; porcine including market hogs, boar/stag, and slow) and poultry (including young and mature chicken, young turkey, and duck). Tissue homogenates were ashed, and residual materials were dissolved in hydrochloric acid for analysis by atomic absorption spectroscopy. Statistical summaries of data are provided for the trace metals lead, cadmium, cobalt, copper, iron, manganese, nickel, and zinc. The heavy metals of toxicological concern, lead and cadmium, are emphasized in this study. Lead and cadmium were rarely detected in muscle (0.2-0.5% positive among 2314 animals sampled). Lead was also infrequently detected in liver (1.8% positive) and kidney (2.4% positive). Nearly 46% of livers analyzed were positive for cadmium, and approximately 78 of kidney samples were positive for cadmium. No regulatory limits are established in the United States for the trace metals reported in this study, although restrictions on the use of kidneys from mature poultry as human food have been established because of concern about potential cadmium levels. Kidneys from this study, more frequently than livers, bore cadmium levels that exceeded the regulatory limits of other countries or organizations. Regulatory implications of the data are discussed. 23 refs., 7 tabs.

  1. Trace Metal Source Terms in Carbon Sequestration Environments

    SciTech Connect

    Karamalidis, Athanasios K; Torres, Sharon G; Hakala, J Alexandra; Shao, Hongbo; Cantrell, Kirk J; Carroll, Susan

    2012-02-05

    Carbon dioxide sequestration in deep saline and depleted oil geologic formations is feasible and promising, however, possible CO₂ or CO₂-saturated brine leakage to overlying aquifers may pose environmental and health impacts. The purpose of this study was to experimentally define trace metal source terms from the reaction of supercritical CO₂, storage reservoir brines, reservoir and cap rocks. Storage reservoir source terms for trace metals are needed to evaluate the impact of brines leaking into overlying drinking water aquifers. The trace metal release was measured from sandstones, shales, carbonates, evaporites, basalts and cements from the Frio, In Salah, Illinois Basin – Decatur, Lower Tuscaloosa, Weyburn-Midale, Bass Islands and Grand Ronde carbon sequestration geologic formations. Trace metal dissolution is tracked by measuring solution concentrations over time under conditions (e.g. pressures, temperatures, and initial brine compositions) specific to the sequestration projects. Existing metrics for Maximum Contaminant Levels (MCLs) for drinking water as defined by the U.S. Environmental Protection Agency (U.S. EPA) were used to categorize the relative significance of metal concentration changes in storage environments due to the presence of CO₂. Results indicate that Cr and Pb released from sandstone reservoir and shale cap rock exceed the MCLs by an order of magnitude while Cd and Cu were at or below drinking water thresholds. In carbonate reservoirs As exceeds the MCLs by an order of magnitude, while Cd, Cu, and Pb were at or below drinking water standards. Results from this study can be used as a reasonable estimate of the reservoir and caprock source term to further evaluate the impact of leakage on groundwater quality.

  2. Removal of trace metal contaminants from potable water by electrocoagulation.

    PubMed

    Heffron, Joe; Marhefke, Matt; Mayer, Brooke K

    2016-01-01

    This study investigated the effects of four operational and environmental variables on the removal of trace metal contaminants from drinking water by electrocoagulation (EC). Removal efficiencies for five metals (arsenic, cadmium, chromium, lead and nickel) were compared under varying combinations of electrode material, post-treatment, water composition and pH. Iron electrodes out-performed aluminum electrodes in removing chromium and arsenic. At pH 6.5, aluminum electrodes were slightly more effective at removing nickel and cadmium, while at pH 8.5, iron electrodes were more effective for these metals. Regardless of electrode, cadmium and nickel removal efficiencies were higher at pH 8.5 than at pH 6.5. Post-EC treatment using membrane filtration (0.45 μm) enhanced contaminant removal for all metals but nickel. With the exception of lead, all metals exhibited poorer removal efficiencies as the ionic strength of the background electrolyte increased, particularly in the very high-solids synthetic groundwaters. Residual aluminum concentrations were lowest at pH 6.5, while iron residuals were lowest in low ionic strength waters. Both aluminum and iron residuals required post-treatment filtration to meet drinking water standards. EC with post-treatment filtration appears to effectively remove trace metal contaminants to potable water standards, but both reactor and source water parameters critically impact removal efficiency. PMID:27324564

  3. Removal of trace metal contaminants from potable water by electrocoagulation

    NASA Astrophysics Data System (ADS)

    Heffron, Joe; Marhefke, Matt; Mayer, Brooke K.

    2016-06-01

    This study investigated the effects of four operational and environmental variables on the removal of trace metal contaminants from drinking water by electrocoagulation (EC). Removal efficiencies for five metals (arsenic, cadmium, chromium, lead and nickel) were compared under varying combinations of electrode material, post-treatment, water composition and pH. Iron electrodes out-performed aluminum electrodes in removing chromium and arsenic. At pH 6.5, aluminum electrodes were slightly more effective at removing nickel and cadmium, while at pH 8.5, iron electrodes were more effective for these metals. Regardless of electrode, cadmium and nickel removal efficiencies were higher at pH 8.5 than at pH 6.5. Post-EC treatment using membrane filtration (0.45 μm) enhanced contaminant removal for all metals but nickel. With the exception of lead, all metals exhibited poorer removal efficiencies as the ionic strength of the background electrolyte increased, particularly in the very high-solids synthetic groundwaters. Residual aluminum concentrations were lowest at pH 6.5, while iron residuals were lowest in low ionic strength waters. Both aluminum and iron residuals required post-treatment filtration to meet drinking water standards. EC with post-treatment filtration appears to effectively remove trace metal contaminants to potable water standards, but both reactor and source water parameters critically impact removal efficiency.

  4. Removal of trace metal contaminants from potable water by electrocoagulation

    PubMed Central

    Heffron, Joe; Marhefke, Matt; Mayer, Brooke K.

    2016-01-01

    This study investigated the effects of four operational and environmental variables on the removal of trace metal contaminants from drinking water by electrocoagulation (EC). Removal efficiencies for five metals (arsenic, cadmium, chromium, lead and nickel) were compared under varying combinations of electrode material, post-treatment, water composition and pH. Iron electrodes out-performed aluminum electrodes in removing chromium and arsenic. At pH 6.5, aluminum electrodes were slightly more effective at removing nickel and cadmium, while at pH 8.5, iron electrodes were more effective for these metals. Regardless of electrode, cadmium and nickel removal efficiencies were higher at pH 8.5 than at pH 6.5. Post-EC treatment using membrane filtration (0.45 μm) enhanced contaminant removal for all metals but nickel. With the exception of lead, all metals exhibited poorer removal efficiencies as the ionic strength of the background electrolyte increased, particularly in the very high-solids synthetic groundwaters. Residual aluminum concentrations were lowest at pH 6.5, while iron residuals were lowest in low ionic strength waters. Both aluminum and iron residuals required post-treatment filtration to meet drinking water standards. EC with post-treatment filtration appears to effectively remove trace metal contaminants to potable water standards, but both reactor and source water parameters critically impact removal efficiency. PMID:27324564

  5. Trace metal anomalies in bleached Porites coral at Meiji Reef, tropical South China Sea

    NASA Astrophysics Data System (ADS)

    Li, Shu; Yu, Kefu; Zhao, Jianxin; Feng, Yuexing; Chen, Tianran

    2016-04-01

    Coral bleaching has generally been recognized as the main reason for tropical coral reef degradation, but there are few long-term records of coral bleaching events. In this study, trace metals including chromium (Cr), copper (Cu), molybdenum (Mo), manganese (Mn), lead (Pb), tin (Sn), titanium (Ti), vanadium (V), and yttrium (Y), were analyzed in two Porites corals collected from Meiji Reef in the tropical South China Sea (SCS) to assess differences in trace metal concentrations in bleached compared with unbleached coral growth bands. Ti, V, Cr, and Mo generally showed irregular fluctuations in both corals. Bleached layers contained high concentrations of Mn, Cu, Sn, and Pb. Unbleached layers showed moderately high concentrations of Mn and Cu only. The different distribution of trace metals in Porites may be attributable to different selectivity on the basis of vital utility or toxicity. Ti, V, Cr, and Mo are discriminated against by both coral polyps and zooxanthellae, but Mn, Cu, Sn, and Pb are accumulated by zooxanthellae and only Mn and Cu are accumulated by polyps as essential elements. The marked increase in Cu, Mn, Pb, and Sn are associated with bleaching processes, including mucus secretion, tissue retraction, and zooxanthellae expulsion and occlusion. Variation in these trace elements within the coral skeleton can be used as potential tracers of short-lived bleaching events.

  6. The effect of solid metal composition on solid metal/ liquid metal partitioning of trace elements

    NASA Astrophysics Data System (ADS)

    Rai, N.; van Westrenen, W.

    2010-12-01

    Fundamental understanding of the partitioning behaviour of elements between different core and/or mantle phases is needed to constrain processes of planetary differentiation and evolution. The partitioning behaviour of elements between solid metal and liquid metal in the Fe-S system, of relevance to core crystallisation in planetesimals and the terrestrial planets, has been investigated by several workers [1-6], most of whom [1-5] conclude that variations in partition coefficients can be explained by variations in melt composition. However, recently Stewart et al. [6] showed that the crystal-lattice strain model commonly used to describe silicate mineral - silicate melt partitioning can be applied to partially molten metallic systems. This suggests the structure of the solid metal also plays a role in determining solid metal / molten metal partitioning. Here, we investigate the effect of the structure of the solid metal in the Fe-S system on solid/liquid metal partitioning by obtaining new element partitioning data at pressures between 0.5 and 3 GPa. The effect of the solid metal is isolated from pressure-temperature-melt composition effects by performing experiments at constant P and T with two Fe-S bulk compositions on either side of the eutectic composition. In addition to the effect of solid metal composition we investigate the effects of pressure and S content on trace element partitioning behaviour and the application of the lattice strain model to our results. Starting mixtures were doped with several hundred ppm levels of trace elements Ni, Co, W, Mo, V, Nb, Ta, Sn, Cu, Pb, Zn, Cr, Mn, P, Ge,. Experiments were performed using a QUICKPress piston cylinder apparatus at the VU University, Amsterdam using alumina capsules. Experiments were heated to 1073 K at pressure and allowed to sinter for a duration of 10 hours before the temperature was raised at a rate of 50 K / min to the target value. Preliminary EPMA data for a 1 GPa experiment with FeS as the solid

  7. Adsorption of humic acids and trace metals in natural waters

    NASA Technical Reports Server (NTRS)

    Leung, W. H.

    1982-01-01

    Studies concerning the interactions between suspended hydrous iron oxide and dissolved humic acids and trace metals are reported. As a major component of dissolved organic matters and its readiness for adsorption at the solid/water interface, humic acids may play a very important role in the organometallic geochemistry of suspended sediments and in determining the fate and distribution of trace metals, pesticides and anions in natural water systems. Most of the solid phases in natural waters contain oxides and hydroxides. The most simple promising theory to describe the interactions of hydrous iron oxide interface is the surface complex formation model. In this model, the adsorptions of humic acids on hydrous iron oxide may be interpreted as complex formation of the organic bases (humic acid oxyanions) with surface Fe ions. Measurements on adsorptions were made in both fresh water and seawater. Attempts have been made to fit our data to Langmuir adsorption isotherm. Adsorption equilibrium constants were determined.

  8. Behavior of trace metals in simulated gasification conditions

    SciTech Connect

    Benson, S.A.; Erickson, T.A.; Zygarlicke, C.J.

    1995-03-01

    The fate of trace metals is being investigated in two emerging coal gasification electric power-generating systems: integrated gasification combined cycle (IGCC) and integrated gasification fuel cell (IGFC). Some of the trace metals in coal are considered air toxics when released into the atmosphere and can also cause the degradation of fuel cell efficiency as a result of contamination. The fate of trace metals during coal conversion in GCC and IGFC systems is closely tied to how the trace metals are associated in the coal and gasification conditions. Bench- and pilot-scale gasification experiments were performed using Illinois No. 6 coal to determine the partitioning of mercury, selenium, arsenic, nickel, cadmium, lead, and chromium into gas, liquid, and solid phases as a function of gasification conditions and coal composition. Entrained ash was collected from the small-scale reactor using a multicyclone and impinger sampling train. Coal analysis revealed arsenic, mercury, nickel, lead, and selenium to be primarily associated with pyrite. Chromium was associated primarily with clay minerals, and cadmium appeared to have mostly an organic association. The partitioning during gasification indicated that chromium, lead, and nickel were enriched in the small ash particulate fraction (less than 1.5 {mu}m), while arsenic, selenium, and mercury were depleted in the particulate and more enriched in the vapor-phase fraction (collected in the impingers). Oxygen contents were varied to represent both combustion and gasification systems. Most of the work was conducted at lower oxygen-to-carbon ratios. Lower oxygen-to-carbon ratios resulted in more reducing environments in the gasification system, which appeared to drive more mercury to the vapor phase. Under constant oxygen-to-carbon ratios, mercury, selenium, and cadmium showed increasing volatility with increasing reaction zone temperature.

  9. Trace metals in fleece wool and correlations with yellowness.

    PubMed

    King, A L; Millington, K R

    2013-03-01

    The presence of copper and iron in metal-doped wool has been shown previously to be associated with the production of free radicals and yellowing in photo-irradiated wool. In this study, the yellowness and trace metal content of 700 wool samples was measured to determine if photoyellowing, catalysed by metals, is a major determinant of the colour of fleece wool. Iron and copper content did not positively correlate with yellowness and yellower wool tended to have lower levels of these metals. Instead, a strong positive correlation of yellowness with the calcium, manganese and magnesium content was observed in yellow wools. High levels of calcium and magnesium is consistent with biofilm formation by Pseudomonas bacteria that have previously been associated with non-scourable staining of wool. PMID:23292316

  10. Mobility of trace metals in retention pond sediments.

    PubMed

    Durand, C; Ruban, V; Amblès, A

    2004-08-01

    This paper presents the results of a study on trace metal mobility in the sediments of several road and urban infiltration/decantation ponds in France; the trace metal concentrations are indeed high. The potential mobility of trace metals (cadmium, nickel, chromium, copper, lead and zinc) was evaluated by application of the sequential extraction BCR protocol. Results have been compared with those from the IHSS protocol, which allows for the extraction of various forms of organic matter. Cadmium is the most easily exchangeable element in the case of variations in physical-chemical conditions (50% to 60% of Cd is exchangeable and 70% to 80% of Cd remains within the fulvic acid fraction) and is thus easily releasable within an acidic medium. Zinc is also potentially mobile and stays mainly concentrated in fulvic acids, except in the case of the Ronchin sediment (more than 50% in humin). In contrast, nickel and chromium are primarily present in the residual fraction and do not exhibit high mobility. Copper and lead are concentrated in both the humic acid fraction (IHSS protocol) and the organic phase (BCR scheme); consequently, their mobility is limited. PMID:15366555

  11. Trace metal/phytoplankton interactions in the Skagerrak

    NASA Astrophysics Data System (ADS)

    Croot, P. L.; Karlson, B.; Wulff, A.; Linares, F.; Andersson, K.

    2002-06-01

    Algal community species composition, as estimated by high performance liquid chromatography (HPLC) pigments and microscopy analysis, and trace metal speciation (Cu and Co) and distributions (Fe, Zn, Co and Cu) were measured along a summer transect across the Skagerrak. In waters of Baltic origin, with elevated trace metals levels, but very low macronutrients, a mix of dinoflagellates and haptophytes dominated the low biomass. In the Jutland current, which had high dissolved iron concentrations, a mixed bloom (4-6 μg/l chl a) of diatoms (major species— Leptocylindricus danica) and dinoflagellates ( Ceratium sp.) was present. In the waters of the central Skagerrak derived from the North Sea, below the low salinity Baltic water, a large diatom (major species— L. danica) bloom (7.7 μg/l) was present at 35 m. This bloom formed below the pycnocline, and was located at the nutricline for silicate. The lowest concentrations of trace metals were found in the water of North Sea origin. Synechococcus-like cyanobacteria were observed in the upper waters across the survey area, as were strong binding ligands for Cu, but no clear numerical relationship existed between them, as had been observed by Moffett [Deep-Sea Res. 42 (1995) 1273]in the Sargasso Sea. The [Co]/[Zn] hypothesis of Sunda and Huntsman [Limnol. Oceanogr. 40 (1995) 1404] for coccolithophorids and diatoms was examined using the field data collected.

  12. Source apportionment of trace metals in river sediments: A comparison of three methods.

    PubMed

    Chen, Haiyang; Teng, Yanguo; Li, Jiao; Wu, Jin; Wang, Jinsheng

    2016-04-01

    Increasing trace metal pollution in river sediment poses a significant threat to watershed ecosystem health. Identifying potential sources of sediment metals and apportioning their contributions are of key importance for proposing prevention and control strategies of river pollution. In this study, three advanced multivariate receptor models, factor analysis with nonnegative constraints (FA-NNC), positive matrix factorization (PMF), and multivariate curve resolution weighted-alternating least-squares (MCR-WALS), were comparatively employed for source apportionment of trace metals in river sediments and applied to the Le'an River, a main tributary of Poyang Lake which is the largest freshwater lake in China. The pollution assessment with contamination factor and geoaccumulation index suggested that the river sediments in Le'an River were contaminated severely by trace metals due to human activities. With the three apportionment tools, similar source profiles of trace metals in sediments were extracted. Especially, the MCR-WALS and PMF models produced essentially the same results. Comparatively speaking, the weighted schemes might give better solutions than the unweighted FA-NNC because the uncertainty information of environmental data was considered by PMF and MCR-WALS. Anthropogenic sources were apportioned as the most important pollution sources influencing the sediment metals in Le'an River with contributions of about 90%. Among them, copper tailings occupied the largest contribution (38.4-42.2%), followed by mining wastewater (29.0-33.5%), and agricultural activities (18.2-18.7%). To protect the ecosystem of Le'an River and Poyang Lake, special attention should be paid to the discharges of mining wastewater and the leachates of copper tailing ponds in that region. PMID:26736053

  13. Trace Metals in Urban Stormwater Runoff and their Management

    NASA Astrophysics Data System (ADS)

    Li, T.; Hall, K.; Li, L. Y.; Schreier, H.

    2009-04-01

    In past decades, due to the rapid urbanization, land development has replaced forests, fields and meadows with impervious surfaces such as roofs, parking lots and roads, significantly affecting watershed quality and having an impact on aquatic systems. In this study, non-point source pollution from a diesel bus loop was assessed for the extent of trace metal contamination of Cu, Mn, Fe, and Zn in the storm water runoff. The study was carried out at the University of British Columbia (UBC) in the Greater Vancouver Regional District (GVRD) of British Columbia, Canada. Fifteen storm events were monitored at 3 sites from the diesel bus loop to determine spatial and temporal variations of dissolved and total metal concentrations in the storm water runoff. The dissolved metal concentrations were compared with the provincial government discharge criteria and the bus loop storm water quality was also compared with previous studies conducted across the GVRD urban area. To prevent storm water with hazardous levels of contaminants from being discharged into the urban drainage system, a storm water catch basin filter was installed and evaluated for its efficiency of contaminants removal. The perlite filter media adsorption capacities for the trace metals, oil and grease were studied for better maintenance of the catch basin filter. Dissolved copper exceeded the discharge criteria limit in 2 out of 15 cases, whereas dissolved zinc exceeded the criteria in 4 out of 15 cases, and dissolved manganese was below the criteria in all of the events sampled. Dissolved Cu and Zn accounted for 36 and 45% of the total concentration, whereas Mn and Fe only accounted for 20 and 4% of their total concentration, respectively. Since they are more mobile and have higher bioaccumulation potentials, Zn and Cu are considered to be more hazardous to the aquatic environment than Fe and Mn. With high imperviousness (100%) and intensive traffic at the UBC diesel bus loop, trace metal concentrations

  14. Trace metals in heavy crude oils and tar sand bitumens

    SciTech Connect

    Reynolds, J.G.

    1990-11-28

    Fe, Ni, and V are considered trace impurities in heavy crude oils and tar sand bitumens. In order to understand the importance of these metals, we have examined several properties: (1) bulk metals levels, (2) distribution in separated fractions, (3) size behavior in feeds and during processing, (4) speciation as a function of size, and (5) correlations with rheological properties. Some of the results of these studies show: (1) V and Ni have roughly bimodal size distributions, (2) groupings were seen based on location, size distribution, and Ni/V ratio of the sample, (3) Fe profiles are distinctively different, having a unimodal distribution with a maximum at relatively large molecular size, (4) Fe concentrations in the tar sand bitumens suggest possible fines solubilization in some cases, (5) SARA separated fractions show possible correlations of metals with asphaltene properties suggesting secondary and tertiary structure interactions, and (6) ICP-MS examination for soluble ultra-trace metal impurities show the possibility of unexpected elements such as U, Th, Mo, and others at concentrations in the ppB to ppM range. 39 refs., 13 figs., 5 tabs.

  15. Physiological effects of essential metals on two detritivores: Atyaephyra desmarestii (Millet) and Echinogammarus meridionalis (Pinkster).

    PubMed

    Quintaneiro, Carla; Ranville, James F; Nogueira, António J A

    2016-06-01

    Freshwater ecosystems are essential for humans; however, input of several types of contamination has led to the degradation of these ecosystems. Thus, it is urgent to assess their health to allow actions for prevention and remediation. The level of trace metals can be enhanced by natural or anthropogenic sources. Essential metals, such as copper and zinc, become toxic when present in the environment above threshold concentrations. To evaluate the physiological effects of these 2 essential metals for 2 freshwater detritivores, the shrimp Atyaephyra desmarestii and the amphipod Echinogammarus meridionalis, acute tests were performed. Forty-eight hour median lethal concentration (LC50) values were estimated for these species using static bioassays with copper and zinc. Sublethal assays for both metals with several phases were also done to evaluate the effects on feeding behavior. The LC50 values of copper for the shrimp A. desmarestii and amphipod E. meridionalis were 0.128 mg/L and 0.050 mg/L and those of zinc were 7.951 mg/L and 11.860 mg/L, respectively. The results indicated that copper is more toxic to both species. Only E. meridionalis showed deleterious effects of copper on feeding rate. Zinc showed some tendency for feeding inhibition in both species. Environ Toxicol Chem 2016;35:1442-1448. © 2015 SETAC. PMID:26472099

  16. Essential helix interactions in the anion transporter domain of prestin revealed by evolutionary trace analysis.

    PubMed

    Rajagopalan, Lavanya; Patel, Nimish; Madabushi, Srinivasan; Goddard, Julie Anne; Anjan, Venkat; Lin, Feng; Shope, Cindy; Farrell, Brenda; Lichtarge, Olivier; Davidson, Amy L; Brownell, William E; Pereira, Fred A

    2006-12-01

    Prestin, a member of the SLC26A family of anion transporters, is a polytopic membrane protein found in outer hair cells (OHCs) of the mammalian cochlea. Prestin is an essential component of the membrane-based motor that enhances electromotility of OHCs and contributes to frequency sensitivity and selectivity in mammalian hearing. Mammalian cells expressing prestin display a nonlinear capacitance (NLC), widely accepted as the electrical signature of electromotility. The associated charge movement requires intracellular anions reflecting the membership of prestin in the SLC26A family. We used the computational approach of evolutionary trace analysis to identify candidate functional (trace) residues in prestin for mutational studies. We created a panel of mutations at each trace residue and determined membrane expression and nonlinear capacitance associated with each mutant. We observe that several residue substitutions near the conserved sulfate transporter domain of prestin either greatly reduce or eliminate NLC, and the effect is dependent on the size of the substituted residue. These data suggest that packing of helices and interactions between residues surrounding the "sulfate transporter motif" is essential for normal prestin activity. PMID:17151276

  17. Urinary Concentrations of Toxic and Essential Trace Elements among Rural Residents in Hainan Island, China

    PubMed Central

    Inoue, Yosuke; Umezaki, Masahiro; Jiang, Hongwei; Li, Dandan; Du, Jianwei; Jin, Yuming; Yang, Bin; Li, Bai; Li, Yufeng; Watanabe, Chiho

    2014-01-01

    Background: Toxic element exposure and essential trace element consumption may have changed after the Chinese economy transformed to a market-oriented system. The objectives of this study were to measure urinary concentrations of toxic (arsenic, cadmium, lead) and essential trace (selenium, zinc, copper) elements among rural residents in Hainan, China and to examine if variations in economic development are linked to differences in toxic and trace element exposure. Methods: We conducted a questionnaire-based survey and undertook anthropometric measurements of residents aged ≥20 years (n = 599). Urinary samples were collected and analyzed using inductively coupled plasma mass spectrometry. Results: The median (μg/g creatinine) element concentrations were: arsenic, 73.2; cadmium, 1.8; lead, 3.1; selenium, 36.5; zinc, 371; and copper, 11.0. Intra-community variation in element concentrations was explained by age (arsenic, cadmium, zinc and copper), sex (arsenic, cadmium and selenium: higher in females; zinc: higher in males), body mass index (cadmium) and individual involvement in the market economy as indexed by agrochemical use (lead and selenium). The degree of community-level economic development, which was determined by the proportion of people living in better housing among the study communities, was positively associated with cadmium concentration. Conclusions: The degree of community-level economic development was positively associated with urinary cadmium concentration while individual involvement in the market economy was positively associated with lead and selenium. PMID:25514155

  18. Trace metals geochemistry of Bengkulu river and estuary

    NASA Astrophysics Data System (ADS)

    Firdaus, M. Lutfi; Darti, Puspa; Alwi, Wiwit; Swistoro, Eko; Sundaryono, Agus; Ruyani, Aceng

    2015-09-01

    Unique feature of Indonesian archipelago in addition to its location that settled between the Pacific Ocean and the Indian Ocean has made Indonesian seas as important parts of the world ocean system. In contrast, research on Indonesian seas including its marine geochemistry is scarce. Research findings have proven that Indonesian seas and its characteristics, such as Indonesian throughflow, are important in the seawater thermohaline circulation that affect world's global climate. The transports of mass and heat from the Pacific into the Indian Ocean are crucial for the oceanic circulation and sea surface temperatures. It is only until recently known that water masses movement could be traced using chemical elements such as Zr and Hf. In modern ocean, sources of these chemicals are mostly from continents. Chemicals had been brought to the oceans through river, estuary, coastal and eventually open seawater. We have analyzed selected important trace metals of Bengkulu river and estuary starting from upper stream of Bengkulu River to coastal seawater of the Indian Ocean. Concentrations of trace metals in the sample were determined by inductively coupled plasma - optical emission spectrometry (ICP-OES). Dissolved and labile particulate concentrations of Al, Fe, Mn, V, Sr and Zn are reported in this study.

  19. Trace metal concentrations and their transfer from sediment to leaves of four common aquatic macrophytes.

    PubMed

    Łojko, Renata; Polechońska, Ludmiła; Klink, Agnieszka; Kosiba, Piotr

    2015-10-01

    In the present study, the concentrations of trace and alkali metals in leaves of four common helophytes, Sparganium erectum, Glyceria maxima, Phalaris arundinacea, and Phragmites australis, as well as in corresponding water and bottom sediments were investigated to ascertain plant bioaccumulation ability. Results showed that Mn and Fe were the most abundant trace metals in all plant species, while Co and Pb contents were the lowest. Leaves of species studied differed significantly in respect of element concentrations. The highest concentrations of Mg, Na, Fe, Mn, Cu, Pb, and Ni were noted in S. erectum while the highest contents of Co, Ca, Zn, and Cr in Phalaris arundinacea. Phragmites australis contained the lowest amounts of most elements. Concentrations of Co, Cr, Fe, and Mn in all species studied and Ni in all except for Phragmites australis were higher than natural for hydrophytes. The leaves/sediment ratio was more than unity for all alkali metals as well as for Cu and Mn in Phragmites australis; Cr, Co, and Zn in Phalaris arundinacea; Cr and Mn in S. erectum; and Cr in G. maxima. High enrichment factors and high levels of toxic metals in the species studied indicated a special ability of these plants to absorb and store certain non-essential metals and, consequently, their potential for phytoremediation of contaminated aquatic ecosystems. PMID:26004561

  20. First assessment of trace metal concentration in mangrove crab eggs and other tissues, SE Brazil.

    PubMed

    de Almeida, Eduardo Vianna; Kütter, Vinicius Tavares; Marques, Eduardo Duarte; da Silva-Filho, Emmanoel Vieira

    2016-07-01

    The mangrove crab Ucides cordatus is widespread in the Brazilian coast, which has an important role in nutrient cycling. This species reproduces in summer and females carry eggs about a month, when they maintain contact with water and sediments. It remains unclear if trace metals can be absorbed or adsorbed by the eggs during development. The present study aims to investigate, for the first time, trace metal concentrations in ovigerous female tissues and eggs of U. cordatus in two areas with different metal pollution levels in the Southeastern Brazil. Samples were collected in two different mangroves, Guanabara Bay (GB) highly polluted environment and Paraíba do Sul River (PSR). In both populations, we observed significant increase of V, Cr, and Mn concentrations along eggs maturation. The higher metals averages were found in PSR population. This trend was reported since the 1990s and lower concentrations in GB marine organisms were attributed to reducing conditions, high organic load, and the presence of sulfide ions. These conditions restrict the bioavailability of metals in the bay, with exception of Mn. No significant differences were observed in gills and muscles. In both populations of the present study, V, Zn, As, and Pb were higher in eggs of initial stage, whereas Mn, Ni, Cu, and Cd were higher in hepatopancreas. Beside this, V, Cr, Mn, As, and Pb showed an increase concerning egg development. Thus, V, As, and Pb in eggs come from two sources previous discussed: females and environment. Zinc came mainly from females due to essential function. Those new information should be considered as one of the mechanisms of trace metal transfer to the trophic chain, between benthonic and pelagic environment. PMID:27318940

  1. Contamination from an affluent of Furnas reservoir by trace metals.

    PubMed

    Cavalcanti, P P; Rodrigues, L C A; Beijo, L A; Barbosa, S; Xavier, T T; Magalhães, F

    2014-11-01

    This study aims to determine concentrations and characterize trace metals distribution in an affluent of Furnas reservoir, Alfenas-MG. Water and sediment samples were taken monthly, 2010/10-2011/07 in five sites of Córrego do Pântano for subsequent determination of Pb, Cd and Zn levels by chemical analysis. The stream studied is in disagreement with Brazilian legislation for Class II water bodies (CONAMA 357). The highlights are the unsuitable concentrations of Pb for human consumption, according to Ministry of Health 2914 decree, providing risk for population. PMID:25627598

  2. Spatial uncertainty of joint health risk of multiple trace metals in rice grain in Jiaxing city, China.

    PubMed

    Qu, Mingkai; Huang, Biao; Li, Weidong; Zhang, Chuanrong; Zhao, Yongcun

    2015-01-01

    Trace metals in rice may affect human health if their concentrations reach risk levels in the human body due to long-term ingestion. In this study, concentrations of five trace metals (Cd, Cr, Cu, Pb and Zn) in field-sampled rice grains were measured at 285 sampling sites in Jiaxing city, China. The objective was to map the spatial distribution and uncertainty of the potential human health risk of trace metals in local rice grains at a regional scale. The probability map of multiple trace metals that tend to be hazardous was produced based on the permissible limits in Chinese National Standards. It showed higher probabilities, which exceeded the national standards, for one or more of trace metals in rice grains were mainly located in several small subareas around the center of the study area. We used the Target Hazard Quotient (THQ) index and the Total THQ (TTHQ) index to represent the potential human health risks caused by individual and multiple trace metals in local rice grains. The TTHQ was essentially regarded as an integrative uniform rice quality index in this study. Stochastic simulation was then conducted to simulate the TTHQ for mapping the spatial distribution and uncertainty of the total potential health risk. Probability maps of different risk grades for TTHQ indicated that most places were in unsafe grades. In general, maps of site-specific health risks posed by trace metals in local rice grains and associated uncertainty information are valuable to spatial decision making in agricultural planning, rice uses, and environmental management. PMID:25418210

  3. Assessment of essential elements and heavy metals content on Mytilus galloprovincialis from river Tagus estuary.

    PubMed

    Santos, I; Diniz, M S; Carvalho, M L; Santos, J P

    2014-06-01

    Trace elemental content was analysed in edible tissues of Mytilus galloprovincialis collected in five different sampling areas near the mouth of river Tagus estuary in Lisbon. The concentrations of essential elements (S, K, Ca, Fe, Cu, Zn, As, Br and Sr) were determined by energy-dispersive X-ray fluorescence (EDXRF) spectrometry, while toxic elements (Cr, Cd, Hg, Se and Pb) were measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results show that the essential elements K and S are present at the highest concentrations in all the studied samples reaching 2,920 and 4,520 μg g(-1) (fresh weight), respectively. The highest levels of heavy metals found were in two areas close to the city for Pb and Cd, but below the maximum allowed values. PMID:24763710

  4. Distribution and partition of trace metals in the Amazon basin

    NASA Astrophysics Data System (ADS)

    Seyler, Patrick T.; Boaventura, Geraldo R.

    2003-05-01

    The distribution of trace metals (V, Cr, Mn, Co, Cu, Zn, As, Rb, Sr, Mo, Cd, Sb, Cs, Ba, U) was investigated in surface waters and associated particulates in the Amazon mainstream (Solimões and Amazon rivers). Dissolved V, Cu, As, Sr, Ba, U correlate with major ions and appear to be predominantly derived from soluble rocks occurring in the Amazon upper basin. These elements appear conservative in waters and are progressively diluted by less-concentrated waters coming from the lowland and shield areas. A monthly time series obtained at the Óbidos gauging station shows that temporal variability of trace element concentrations reflects the source, remobilization and/or biological processes occurring in the channel or in the surrounding floodplain lakes. The trace element concentrations in the particulate matter show a clear relationship with the location of the samples. V, Co, Cr, Mn, Sr, Cs and Ba concentrations are higher in the Solimões and the Rio Negro is enriched in Fe, Al and Zn. In the Rio Solimões, V, Cr, Mn, Co, Ni, Zn, Cs and Pb are almost entirely carried by the river particulate matter; Cu, Rb, Sr, Ba and U are transported mainly by the suspended particles, but a dissolved phase contributes to the transport. In the Rio Negro, the proportion of elements transported by the dissolved phase is higher for the whole set of elements. The implications of these results allow us to compute the fluxes from the Amazon River to the Atlantic Ocean.

  5. Contribution of trace metals in structuring in situ macroinvertebrate community composition along a salinity gradient

    SciTech Connect

    Peeters, E.T.H.M.; Gardeniers, J.J.P.; Koelmans, A.A.

    2000-04-01

    Macroinvertebrates were studied along a salinity gradient in the North Sea Canal, The Netherlands, to quantify the effect of trace metals (cadmium, copper, lead, zinc) on community composition. In addition, two methods for assessing metal bioavailability (normalizing metal concentrations on organic carbon and on the smallest sediment fraction) were compared. Factor analyses showed that normalizing trace metals resulted in an improved separation of trace metals from ecological factors (depth, organic carbon, granulometry, and chloride). The variation in the macroinvertebrate data was partitioned into four sources using partial canonical correspondence analysis, with the partitions being purely ecological factors, purely trace metals, mutual ecological factors and trace metals, and unexplained. Partial canonical correspondence analysis applied to total and normalized trace metal concentrations gave similar results in terms of unexplained variances. However, normalization on organic carbon resulted in the highest percentage of variation explained by purely ecological factors and purely trace metals. Accounting for bioavailability thus improves the identification of factors affecting the in situ community structure. Ecological factors explained 45.4% and trace metals 8.6% of the variation in the macroinvertebrate community composition in the ecosystem of the North Sea Canal. These contributions were significant, and it is concluded that trace metals significantly affected the community composition in an environment with multiple stressors. Variance partitioning is recommended for incorporation in further risk assessment studies.

  6. Baseline study on essential and trace elements in polished rice from South Korea.

    PubMed

    Jung, Myung Chae; Yun, Seong-Taek; Lee, Jin-Soo; Lee, Jong-Un

    2005-09-01

    In 2000, 63 (polished) white rice samples were collected in eight administrative areas all over South Korea and analyzed for 16 elements by inductively coupled plasma atomic emission spectrometry (ICP-AES). Potassium had the highest content, next to Mg, Ca, Si, Zn, Na, Al and Fe. Most of the samples contained worldwide average concentrations of essential and trace elements in rice grains reported by various researches. For inter-area differences in those elements in the rice, the statistical analysis showed no significant differences (p > 0.05) among the eight administrative areas, suggesting that inter-area differences were not substantial in most cases. Thus, the present data can be used as national background levels of elements in rice produced in South Korea. Using the published data on daily consumption of rice in South Korea, it was possible to estimate the daily intake of As, Cd, Cu, Pb and Zn via rice. The results showed that a regular consumption of rice produced in Korea plays an important role in accumulation of essential and trace elements in Korean, especially for farm-households consuming relatively large amounts of rice. PMID:16237601

  7. Trace metals in urban streams and detention ponds

    SciTech Connect

    Licsko, Z.J.; Struger, J.

    1995-12-31

    Trace metal levels were monitored over a nine month period in two urban creeks in the Hamilton Harbour watershed and in two urban stormwater retention ponds in Guelph, Ontario. Samples were collected both during dry or non-event periods and immediately after wet weather events. Both water and surficial sediment samples were collected and tested for cadmium, copper, lead, mercury, nickel, and zinc. In almost all cases during wet weather conditions, Canadian Water Quality Guidelines for the protection of freshwater aquatic life were exceeded in water for lead (>7 mg/L), copper (>4 mg/L), and zinc (>30 mg/L) . Both stormwater ponds accumulated trace metals in sediment to levels above the lowest effect level guideline for the protection and management of aquatic sediment in Ontario, and, in the case of zinc (> 820 ug/g), above the severe effect level guideline. These levels of contamination raise serious concerns about the use of these and similar facilities as habitat for biota.

  8. Effects of gypsum on trace metals in soils and earthworms.

    PubMed

    Chen, Liming; Kost, Dave; Tian, Yongqiang; Guo, Xiaolu; Watts, Dexter; Norton, Darrell; Wolkowski, Richard P; Dick, Warren A

    2014-01-01

    Mined gypsum has been beneficially used for many years as an agricultural amendment. A large amount of flue gas desulfurization (FGD) gypsum is produced by removal of SO from flue gas streams when fuels with high S content are burned. The FGD gypsum, similar to mined gypsum, can enhance crop production. However, information is lacking concerning the potential environmental impacts of trace metals, especially Hg, in the FGD gypsum. Flue gas desulfurization and mined gypsums were evaluated to determine their ability to affect concentrations of Hg and other trace elements in soils and earthworms. The study was conducted at four field sites across the United States (Ohio, Indiana, Alabama, and Wisconsin). The application rates of gypsums ranged from 2.2 Mg ha in Indiana to 20 Mg ha in Ohio and Alabama. These rates are 2 to 10 times higher than typically recommended. The lengths of time from gypsum application to soil and earthworm sampling were 5 and 18 mo in Ohio, 6 mo in Indiana, 11 mo in Alabama, and 4 mo in Wisconsin. Earthworm numbers and biomass were decreased by FGD and mined gypsums in Ohio. Among all the elements examined, Hg was slightly increased in soils and earthworms in the FGD gypsum treatments compared with the control and the mined gypsum treatments. The differences were not statistically significant except for the Hg concentration in the soil at the Wisconsin site. Selenium in earthworms in the FGD gypsum treatments was statistically higher than in the controls but not higher than in the mined gypsum treatments at the Indiana and Wisconsin sites. Bioaccumulation factors for nondepurated earthworms were statistically similar or lower for the FGD gypsum treatments compared with the controls for all elements. Use of FGD gypsum at normal recommended agricultural rates seems not to have a significant impact on concentrations of trace metals in earthworms and soils. PMID:25602559

  9. Daily intake of trace metals through coffee consumption in India.

    PubMed

    Suseela, B; Bhalke, S; Kumar, A V; Tripathi, R M; Sastry, V N

    2001-02-01

    The trace element contents of five varieties of instant coffee powder available in the Indian market have been analysed. Ca, Cr, Fe, K, Mg, Mn, Ni, Sr, Zn and Pb, Cd, Cu have been determined using atomic absorption spectrophotometry and differential pulse anodic stripping voltammetry, respectively. The metal levels in the coffee powders observed in this study are comparable with those reported for green coffe beans (Arabica and Robusta variety) reported worldwide with the exception of Sr and Zn, which were on the lower side of the reported values. Concentrations of these metals have been converted into intake figures based on coffee consumption. The daily intakes of the above metals through ingestion of coffee are 1.4 mg, 1.58 microg, 124 microg, 41.5 mg, 4.9 mg, 17.9 microg, 2.9 microg, 3.8 microg, 12.5 microg, 0.2 microg, 0.03 microg and 15.5 microg, respectively. The values, which were compared with the total dietary, intake of metals through ingestion by the Mumbai population, indicate that the contribution from coffee is less than or around 1% for most of the elements except for Cr and Ni which are around 3%. PMID:11288908

  10. Concentration levels of essential and non-essential metals in Ethiopian khat (Catha edulis Forsk).

    PubMed

    Atlabachew, Minaleshewa; Chandravanshi, Bhagwan Singh; Redi, Mesfin

    2010-12-01

    The levels of essential (Ca, Mg, Mn, Fe, Zn, Cr, Cu, and Co) and non-essential (Cd and Pb) metal in six different varieties of Ethiopian khat (Catha edulis Forsk, an evergreen stimulant plant) commonly consumed in the country and exported to the neighboring countries were determined by flame atomic absorption spectrometry. Known weight of oven-dried khat samples were wet-digested using 2 mL of (69-72%) HNO(3) and 2 mL of (70%) HClO(4) for 2 h and 30 min at variable temperature (120-270°C). The mineral contents in the digests were analyzed using flame atomic absorption spectrometer. The following concentrations ranges in fresh-weight basis were recorded in decreasing order: Ca (1,038-2,173 µg/g) > Mg (478.2-812.3 µg/g) > Fe (53.95-82.83 µg/g) >Zn (5.18-9.40 µg/g) >Mn (6.98-8.66 µg/g) >Cu (1.85-5.53 µg/g) > Cr (0.66-3.47 µg/g) >Co (0.41-0.80 µg/g). A wide variation in the mineral contents of khat from different region of Ethiopia was noticed. The toxic metals (Pb and Cd) were not detected in all the samples analyzed. PMID:20177815

  11. Contribution to biomonitoring of some trace metals by deciduous tree leaves in urban areas.

    PubMed

    Tomasević, M; Vukmirović, Z; Rajsić, S; Tasić, M; Stevanović, B

    2008-02-01

    Leaves of the deciduous tree species, horse chestnut (Aesculus hippocastanum L.) and Turkish hazel (Corylus colurna L.) were used as accumulative biomonitors of trace metal pollution in the urban area of Belgrade. Using differential pulse anodic stripping voltametry, trace metal concentrations (Pb, Cu, Zn, Cd) were determined at the single leaf level (ten leaves per species, per month), during two successive years with markedly different atmospheric level of trace metals. Increased trace metal concentrations in the leaves of A. hippocastanum reflected elevated atmospheric trace metal pollution, whereas C. colurna L. did not respond accordingly. The contents of Pb and Zn in soil over the same period also followed this trend. Anatomical analyses, in young as well as in old leaves of both species, indicated typical foliar injuries of plants exposed to stressful air conditions. Water relations that correspond to leaf age may have contributed to the considerable trace metal accumulation in leaves. PMID:17505898

  12. Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies.

    PubMed

    Jiann, Kuo-Tung; Wen, Liang-Saw; Santschi, Peter H

    2016-01-01

    Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination control. Developments of some techniques aiming to reduce trace metal contamination in the last couple of decades have resulted in concentrations reported now being orders of magnitude lower than those in the past. These low concentrations often necessitate preconcentration of water samples prior to instrumental analysis of samples. Since contamination can appear in all phases of trace metal analyses, including sample collection (and during preparation of sampling containers), storage and handling, pretreatments, and instrumental analysis, specific care needs to be taken in order to reduce contamination levels at all steps. The effort to develop and utilize "clean techniques" in trace metal studies allows scientists to investigate trace metal distributions and chemical and biological behavior in greater details. This advancement also provides the required accuracy and precision of trace metal data allowing for environmental conditions to be related to trace metal concentrations in aquatic environments. This protocol that is presented here details needed materials for sample preparation, sample collection, sample pretreatment including preconcentration, and instrumental analysis. By reducing contamination throughout all phases mentioned above for trace metal analysis, much lower detection limits and thus accuracy can be achieved. The effectiveness of "clean techniques" is further demonstrated using low field blanks and good recoveries for standard reference material. The data quality that can be obtained thus enables the assessment of trace metal distributions and their relationships to environmental parameters. PMID:27404762

  13. Anatomically-related variations in trace-metal concentrations in hair

    SciTech Connect

    DeAntonio, S.M.; Katz, S.A.; Scheiner, D.M.; Wood, J.D.

    1982-12-01

    Scalp-hair analysis is used as an indicator of trace-metal concentrations in the human body. The major shortcoming of this approach is the inability to differentiate between endogenous and exogenous trace metals. Our analyses show no correlation between the concentrations of calcium, magnesium, copper, iron, or zinc in scalp hair and pubic hair in 67 donor-matched hair samples. We interpret this as a strong indication that exogenous trace metals make a significant contribution to the results for trace metals in human hair.

  14. Regulation of essential heavy metals (Cu, Cr, and Zn) by the freshwater prawn macrobrachium malcolmsonii (Milne Edwards)

    SciTech Connect

    Vijayram, K.; Geraldine, P.

    1996-02-01

    Despite the low concentrations of heavy metals in the surrounding medium, aquatic organisms take them up and accumulate them in their soft tissues to concentrations several fold higher than those of ambient levels. Knowledge of accumulation patterns of a particular trace metal is a prerequisite for understanding the significance of an observed metal concentration in a particular animal, especially from the aspect of biomonitoring. Many marine invertebrates accumulate heavy metals without any regulation and the accumulation necessarily being associated with mechanisms to store the metals in a detoxified form. Two detoxification mechanisms have been described, both of which may occur in one specimen. Heavy metals can either be bound up in insoluble metalliferous {open_quote}granules{close_quote}, or are bound to soluble metal-binding ligands, such as metallothioneins. Some marine decapod crustaceans have an innate ability to regulate the internal concentrations of essential but potentially toxic metals within a constant level, presumably to meet their metabolic demands. However, at present, there is no such information relating to freshwater decapod crustaceans, especially shrimps which occupy a totally different environment. Macrobrachium malcolmsonii, a potential aquaculture species for freshwater is found in abundance in one of the major Indian rivers, the Cauvery. In the present study, an attempt was made to determine whether the freshwater prawn, M. malcolmsonlii, is able to regulate the three essential elements, copper, chromium and zinc, over a wide range of dissolved concentrations. These three metals were chosen because the Cauvery River receives pollutants containing these metals.

  15. Estimation of essential and trace elements in some medicinal plants by PIXE and PIGE techniques

    NASA Astrophysics Data System (ADS)

    Devi, K. Nomita; Sarma, H. Nandakumar; Kumar, Sanjiv

    2008-04-01

    Proton induced X-ray emission (PIXE) and proton induced γ-ray emission (PIGE) techniques are employed for the determination of essential and trace elements in some commonly used medicinal plants of north east India. Light elements such as Na, Mg, Al and P are determined by PIGE while medium Z elements such as K, Ca, Mn, Fe, Cu, Zn, Rb and Sr are determined by PIXE. Analysis is performed on pellets (thick targets) prepared using powders of the specimens which, in turn, are obtained following a series of processing steps. Plant based biological certified reference materials (CRMs) served as standards for quantification. These elements are found to be present in varying concentrations in the studied plants, with the contents of Mn and Zn being notably large in certain specimens. Medicinal properties possessed by these plants have been correlated with their elemental distribution.

  16. Blood levels of trace metals and amyotrophic lateral sclerosis.

    PubMed

    Peters, Tracy L; Beard, John D; Umbach, David M; Allen, Kelli; Keller, Jean; Mariosa, Daniela; Sandler, Dale P; Schmidt, Silke; Fang, Fang; Ye, Weimin; Kamel, Freya

    2016-05-01

    Some trace metals may increase risk of amyotrophic lateral sclerosis (ALS), whereas others may be beneficial. Our goal was to examine associations of ALS with blood levels of selenium (Se), zinc (Zn), copper (Cu), and manganese (Mn). We conducted a case-control study of 163 neurologist confirmed patients from the National Registry of Veterans with ALS and 229 frequency-matched veteran controls. We measured metal levels in blood using inductively coupled plasma mass spectrometry and estimated odds ratios (ORs) and 95% confidence intervals (CIs) for associations between ALS and a doubling of metal levels using unconditional logistic regression, adjusting for age, gender, and race/ethnicity. ALS was inversely associated with both Se (OR=0.4, 95% CI: 0.2-0.8) and Zn (OR=0.4, 95% CI: 0.2-0.8). Inverse associations with Se were stronger in patients with bulbar compared to spinal onset, worse function, longer diagnostic delay, and longer collection delay; inverse associations with Zn were stronger for those with worse function and longer collection delay. In contrast, ALS was positively associated with Cu (OR=3.4, 95% CI: 1.5-7.9). For Mn, no linear trend was evident (OR=0.9, 95% CI: 0.6-1.3, Ptrend=0.51). Associations of Se, Zn, Cu, and Mn with ALS were independent of one another. Adjustment for lead levels attenuated the positive association of ALS with Cu but did not change associations with Se, Zn, or Mn. In conclusion, Se and Zn were inversely associated with ALS, particularly among those with worse function, suggesting that supplementation with these metals may benefit such patients, while Cu was positively associated with ALS. Deficiencies of Se and Zn and excess Cu may have a role in ALS etiology. PMID:27085208

  17. Trace metals and radionuclides in macroalgae from Moroccan coastal waters.

    PubMed

    Benkdad, Azzouz; Laissaoui, Abdelmourhit; Tornero, Maria Victoria; Benmansour, Moncef; Chakir, ElMahjoub; Garrido, Ignacio Moreno; Moreno, Julian Blasco

    2011-11-01

    Macroalgae species Codium sp, Bangia atropurpurea, Membranoptera alata, Plocamium cartilagineum, Dictyota dichotoma, Fucus spiralis and Stypocaulon scoparia were collected from seven stations along the north coast of Morocco. Samples were analysed to determine activities of naturally occurring radionuclides ((210)Pb, U isotopes and (40)K) and concentrations of metals (Zn, Fe, Co, Cu, Ni, Mn, Pb, Cd, As and Cr) using radiometric and ICP-OES techniques, respectively. Metal concentrations were within ranges reported in the scientific literature, and concentrations of bio-essential elements were in the order Mn>Fe> Zn>Cu in all samples. Brown algae had the highest concentrations of almost all metals, and concentrations decreased in the order brown>red>green algae. With respect to radionuclides, the red alga P. cartilagineum had the highest activities of (210)Pb, in most cases an order of magnitude higher than for the green alga Codium sp. (234)U and (238)U activities in all algae samples were in the range 0.96- 7.61 and 1.16-6.14 Bq/kg dry weight, respectively. Our analyses of radionuclide activities and metal concentrations in marine macroalgae showed large differences among taxa. These results provide insights into which algal species should be used for biomonitoring programmes. PMID:21298402

  18. Admit One: How Essential and Nonessential Metals Gain Entrance into the Cell

    PubMed Central

    Martinez-Finley, Ebany J.; Chakraborty, Sudipta; Fretham, Stephanie; Aschner, Michael

    2016-01-01

    Metals can have a number of detrimental or beneficial effects in the cell, but first they must get in. Organisms have evolved transport mechanisms to get metals that are required, or essential into the cell. Nonessential metals often enter the cell through use of the machinery provided for essential metals. Much work has been done to advance our understanding of how these metals are transported across the plasma and organelle membranes. This review provides an overview of these metal transport processes. PMID:22337135

  19. Predicting the toxicity of sediment-associated trace metals with simultaneously extracted trace metal: Acid-volatile sulfide concentrations and dry weight-normalized concentrations: A critical comparison

    USGS Publications Warehouse

    Long, E.R.; MacDonald, D.D.; Cubbage, J.C.; Ingersoll, C.G.

    1998-01-01

    The relative abilities of sediment concentrations of simultaneously extracted trace metal: acid-volatile sulfide (SEM:AVS) and dry weight- normalized trace metals to correctly predict both toxicity and nontoxicity were compared by analysis of 77 field-collected samples. Relative to the SEM:AVS concentrations, sediment guidelines based upon dry weight-normalized concentrations were equally or slightly more accurate in predicting both nontoxic and toxic results in laboratory tests.

  20. Sources and Contents of Heavy Metals and Other Trace Elements in Animal Manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trace elements are natural and added components of livestock and poultry feeds. Appropriate amounts of these trace elements in the diet of livestock and poultry ensures both health and reproduction. Unfortunately, many times trace metals that are added to livestock diets by producers or feed compani...

  1. Trace metal concentrations in post-hatching cuttlefish Sepia officinalis and consequences of dissolved zinc exposure.

    PubMed

    Le Pabic, Charles; Caplat, Christelle; Lehodey, Jean-Paul; Milinkovitch, Thomas; Koueta, Noussithé; Cosson, Richard Philippe; Bustamante, Paco

    2015-02-01

    In this study, we investigated the changes of 13 trace metal and metalloid concentrations (i.e. Ag, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Se, V, Zn) and their subcellular fractionation in juvenile cuttlefish Sepia officinalis reared in controlled conditions between hatching and 2 months post-hatching. In parallel, metallothionein concentrations were determined. Our results highlighted contrasting changes of studied metals. Indeed, As and Fe concentrations measured in hatchlings suggested a maternal transfer of these elements in cuttlefish. The non-essential elements Ag and Cd presented the highest accumulation during our study, correlated with the digestive gland maturation. During the 6 first weeks of study, soluble fractions of most of essential trace metals (i.e. Co, Cr, Cu, Fe, Se, Zn) slowly increased consistently with the progressive needs of cuttlefish metabolism during this period. In order to determine for the first time in a cephalopod how metal concentrations and their subcellular distributions are impacted when the animals are trace metal-exposed, we studied previously described parameters in juveniles exposed to dissolved Zn at environmental (i.e. 50 μg l(-1)) and sublethal (i.e. 200 μg l(-1)) levels. Moreover, oxidative stress (i.e. glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase activities, and lipid peroxidation (LPO)) was assessed in digestive gland and gills after 1 and 2 months exposures. Our results highlighted no or low ability of this stage of life to regulate dissolved Zn accumulation during the studied period, consistently with high sensitivity of this organism. Notably, Zn exposures caused a concentration-dependent Mn depletion in juvenile cuttlefish, and an increase of soluble fraction of Ag, Cd, Cu without accumulation modifications, suggesting substitution of these elements (i.e. Mn, Ag, Cd, Cu) by Zn. In parallel, metallothionein concentrations decreased in individuals most exposed to Zn. Finally, no

  2. Genetic and geological imprints of evolutionary advance: A trace metal view

    NASA Astrophysics Data System (ADS)

    Rickaby, R. E.; Williams, B. J.

    2010-12-01

    known to increase generally in evolution. It appears that multiple organisms, from very diverse lineages were able to recognise, manage and ultimately make use of the newly available trace metals almost simultaneously. Indeed, the development of increasing use of both Cu and Zn was essential for the synthesis and management of both messengers and connective tissue, key evolutionary steps towards multicellularity. We consider that evolution was chemically constrained, and that average changes in availability of particularly Fe, Zn and Cu, were critical for the systematic development of organisms. Williams, R. J. P., and Frausto da Silva, JJR, The Chemistry of Evolution: The Development of our Ecosystem, Elsevier, The Netherlands, 2006. Williams, R. J. P., and R. E. M. Rickaby, Evolution’s Destiny, submitted.

  3. Inhibitive potentiometric detection of trace metals with ultrathin polypyrrole glucose oxidase biosensor.

    PubMed

    Ayenimo, Joseph G; Adeloju, Samuel B

    2015-05-01

    A method, based on the inhibition of an ultrathin polypyrrole-glucose oxidase (PPy-GOx) potentiometric biosensor response, is described for the detection of Cu(2+), Hg(2+), Cd(2+) and Pb(2+) ions. Based on experimental conditions (0.2 M pyrrole, 500 U mL(-1) GOx, and an applied current density of 0.05 mA cm(-2) and a polymerization period of 500s) previously published by us, PPy-GOx films of approximately 55 nm thick were used to demonstrate the inhibitive potentiometric detection of selected trace metals down to 0.079 μM Cu(2+), 0.025 μM Hg(2+), 0.024 μM Pb(2+) and 0.044 μM Cd(2+). Furthermore, good linear concentration ranges were achieved for Cu(2+) (0.079-16 μM), Hg(2+) (0.025-5 μM), Pb(2+) (0.10-15 μM) and Cd(2+) (0.04-62 μM). The analysis of the nature of the inhibition of glucose oxidase in the PPy-GOx biosensor by these metals was achieved by Dixon and Cornish-Bowden plots. The shapes of the curves (exponential decay, parabolic and linear) obtained for the inhibitors suggest that the inhibition by the metal ions may not be exclusively directed at the essential -SH group, but involve additional binding sites of the enzyme. Dixon and Cornish-Bowden plots suggest that the inhibition is competitive for Cd(2+), while non-competitive inhibition was observed for other metal ions. The ultra-thin PPy-GOx film enabled improved permeability to the metal inhibitors than possible with conventional biosensors with thicker films and, hence, better reflects the actual inhibition effect of the trace metals on the enzyme activity. The use of the ultra-thin film also eliminated the usual need for incubation of the enzyme electrode for a long period in the presence of the inhibitors. Furthermore, a rapid recovery of the enzyme activity was achieved by simply washing the electrode with water and storing in phosphate buffer for 10-15 min. The proposed biosensing approach was successfully used for the detection of individual trace metals in tap water, achieving a 98

  4. BENCH-SCALE TESTING OF SORBENT ADDITIVES FOR TRACE METAL CAPTURE AND RETENTION

    EPA Science Inventory

    The suitability of six minerals; silica, diatomaceous earth, kaolin, bauxite, alumina and attapulgite clay, as potential sorbents for the capture and immobilization of trace metals was evaluated. he behavior of five trace metals; arsenic, cadmium, chromium,, lead and nickel was t...

  5. Estimation of trace metal elements in oral mucosa specimens by using SR-XRF, PIXE, and XAFS.

    PubMed

    Sugiyama, Tomoko; Uo, Motohiro; Wada, Takahiro; Omagari, Daisuke; Komiyama, Kazuo; Noguchi, Tadahide; Jinbu, Yoshinori; Kusama, Mikio

    2015-02-01

    The effects of dissolved elements from metal dental restorations are a major concern in lesions of the oral mucosa, and the evaluation of accumulated metal elements, especially their distribution and chemical state, is essential for determining the precise effects of trace metals. In this study, X-ray fluorescence with synchrotron radiation (SR-XRF) and particle-induced X-ray emission (PIXE) were applied for distribution analysis of the trace metal elements contained in the oral mucosa, and the chemical states of the elements were estimated using X-ray absorption fine structure (XAFS) analysis. Appropriate combination of these analysis techniques, particularly SR-XRF and PIXE, to visualize the distributions of the elements in the oral mucosa allowed for the observation and evaluation of accumulated metal ions and debris. Importantly, the analyses in this study could be carried out using conventional histopathological specimens without damaging the specimens. Therefore, this method would be applicable for the detection of accumulated trace metal elements in biopsy specimens from the oral mucosa. PMID:25522792

  6. Trace metal content in distinct genotypes of human neuroblastoma cells: Preliminary results

    NASA Astrophysics Data System (ADS)

    Ortega, R.; Gouget, B.; Moretto, Ph.; Michelet, C.; Bénard, J.; Sergeant, C.; Llabador, Y.; Simonoff, M.

    1997-07-01

    Some transition metals play important regulatory roles in gene expression. The disturbance of their cellular levels could be involved in oncogene expression and tumorigenesis. Nuclear Microprobe Analysis (NMPA) was used to measure cellular trace metal levels (Mn, Fe, Cu, Zn) in two human neuroblastoma cell lines characterized by distinct genotypes. In this paper, a specific protocol established for sample preparation of neuronal cultured cells is described. Trace metal concentrations in SK-N-SH and IGR-N-91 cells exhibiting respectively a single copy, and 60 copies, of the N- myc oncogene are reported. A brief discussion on experiment design for NMPA of trace metal functions in gene expression is also presented.

  7. Final report on CCQM-K89: Trace and essential elements in Herba Ecliptae

    NASA Astrophysics Data System (ADS)

    Valiente, Liliana; Saxby, David; Merrick, Jeffrey; Kotzeva, Boriana; Mester, Zoltan; Yang, Lu; Willie, Scott; Feng, Liuxing; Wang, Jun; Labarraque, Guillaume; Rienitz, Olaf; Wai-mei Sin, Della; Mok, Chuen-sing; Wong, Siu-kay; Ng, Chi-shing; Fung, Wai-hong; Yau, Ho-pan; Zhu, Yanbei; Yim, Yong-Hyeon; Lee, Kyoung Seok; Kim, In Jung; Lim, Young Ran; Ramirez Cruz, Pedro; Mercader Trejo, Flora E.; Valle Moya, Edith; Santiago Castellanos, Itzel; del Rocio Arvizu Torres, Maria; Manzano, Judith Velina Lara; Konopelko, L. A.; Kustikov, Yu A.; Shin, Richard; Horvat, Milena; Jacimovic, Radojko; Milacic, Radmila; Yafa, Charun; Taebunpakul, Sutthinun; Kaewkhomdee, Nattikarn; Phukphatthanachai, Pranee; Cankur, Oktay; Gonca Coskun, F.; Turk, Gregory C.; Davis, W. Clay; Wood, Laura J.; Murphy, Karen E.; Entwisle, John

    2013-01-01

    The key comparison CCQM-K89 was undertaken to demonstrate the capability of participating NMIs and DIs in measuring the contents of incurred trace elements (total arsenic, cadmium and lead) and essential elements (calcium and zinc) at µg/g (for arsenic, cadmium, lead and zinc) and mg/g (for calcium) levels in a herb matrix sample by various analytical techniques. This key comparison was organized by the Government Laboratory of the Hong Kong Special Administrative Region (GLHK) and agreed at the Inorganic Analysis Working Group Meeting in Hindås, Sweden in October 2010 as a benchmarking exercise with arsenic (a trace element) and calcium (an essential element) chosen as the 'exemplary' elements. It was also agreed that a pilot study CCQM-P126 would be run in parallel with this key comparison. The key comparison serves to facilitate claims by participants on the Calibration and Measurement Capabilities (CMCs) as listed in Appendix C of the Key Comparison Database (KCDB) under the Mutual Recognition Arrangement of the International Committee for Weights and Measures (CIPM MRA). A total of 20 NMIs/DIs registered for this programme and 18 of them submitted their results. Most of the participants used microwave acid digestion methods for sample dissolution. For the instrumental determination, a variety of techniques like ICP-MS, AAS, INAA, ICP-AES were employed by the participants. For this key comparison, inorganic core capabilities have been demonstrated by concerned participants with respect to methods including ICP-MS (without isotope dilution), ID-ICP-MS, ICP-AES, INAA, AAS and ion chromatography with iteratively matrix-matched calibration on the determination of total arsenic, calcium, cadmium, lead and zinc in a matrix of herb. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for

  8. Advanced Gasification Mercury/Trace Metal Control with Monolith Traps

    SciTech Connect

    Musich, Mark; Swanson, Michael; Dunham, Grant; Stanislowski, Joshua

    2010-10-05

    Two Corning monoliths and a non-carbon-based material have been identified as potential additives for mercury capture in syngas at temperatures above 400°F and pressure of 600 psig. A new Corning monolith formulation, GR-F1-2189, described as an active sample appeared to be the best monolith tested to date. The Corning SR Liquid monolith concept continues to be a strong candidate for mercury capture. Both monolith types allowed mercury reduction to below 5-μg/m{sup 3} (~5 ppb), a current U.S. Department of Energy (DOE) goal for trace metal control. Preparation methods for formulating the SR Liquid monolith impacted the ability of the monolith to capture mercury. The Energy & Environmental Research Center (EERC)-prepared Noncarbon Sorbents 1 and 2 appeared to offer potential for sustained and significant reduction of mercury concentration in the simulated fuel gas. The Noncarbon Sorbent 1 allowed sustained mercury reduction to below 5-μg/m{sup 3} (~5 ppb). The non-carbon-based sorbent appeared to offer the potential for regeneration, that is, desorption of mercury by temperature swing (using nitrogen and steam at temperatures above where adsorption takes place). A Corning cordierite monolith treated with a Group IB metal offered limited potential as a mercury sorbent. However, a Corning carbon-based monolith containing prereduced metallic species similar to those found on the noncarbon sorbents did not exhibit significant or sustained mercury reduction. EERC sorbents prepared with Group IB and IIB selenide appeared to have some promise for mercury capture. Unfortunately, these sorbents also released Se, as was evidenced by the measurement of H2Se in the effluent gas. All sorbents tested with arsine or hydrogen selenide, including Corning monoliths and the Group IB and IIB metal-based materials, showed an ability to capture arsine or hydrogen selenide at 400°F and 600 psig. Based on current testing, the noncarbon metal-based sorbents appear to be the most

  9. ADVANCED GASIFICATION MERCURY/TRACE METAL CONTROL WITH MONOLITH TRAPS

    SciTech Connect

    Mark A. Musich; Michael L. Swanson; Grant E. Dunham; Joshua J. Stanislowski

    2010-07-31

    Two Corning monoliths and a non-carbon-based material have been identified as potential additives for mercury capture in syngas at temperatures above 400°F and pressure of 600 psig. A new Corning monolith formulation, GR-F1-2189, described as an active sample appeared to be the best monolith tested to date. The Corning SR Liquid monolith concept continues to be a strong candidate for mercury capture. Both monolith types allowed mercury reduction to below 5-μg/m3 (~5 ppb), a current U.S. Department of Energy (DOE) goal for trace metal control. Preparation methods for formulating the SR Liquid monolith impacted the ability of the monolith to capture mercury. The Energy & Environmental Research Center (EERC)-prepared Noncarbon Sorbents 1 and 2 appeared to offer potential for sustained and significant reduction of mercury concentration in the simulated fuel gas. The Noncarbon Sorbent 1 allowed sustained mercury reduction to below 5-μg/m3 (~5 ppb). The non-carbon-based sorbent appeared to offer the potential for regeneration, that is, desorption of mercury by temperature swing (using nitrogen and steam at temperatures above where adsorption takes place). A Corning cordierite monolith treated with a Group IB metal offered limited potential as a mercury sorbent. However, a Corning carbon-based monolith containing prereduced metallic species similar to those found on the noncarbon sorbents did not exhibit significant or sustained mercury reduction. EERC sorbents prepared with Group IB and IIB selenide appeared to have some promise for mercury capture. Unfortunately, these sorbents also released Se, as was evidenced by the measurement of H2Se in the effluent gas. All sorbents tested with arsine or hydrogen selenide, including Corning monoliths and the Group IB and IIB metal-based materials, showed an ability to capture arsine or hydrogen selenide at 400°F and 600 psig. Based on current testing, the noncarbon metal-based sorbents appear to be the most effective arsine

  10. Trace metal availability and effects on benthic community structure in floodplain lakes.

    PubMed

    van Griethuysen, Corine; van Baren, Joyce; Peeters, Edwin T H M; Koelmans, Albert A

    2004-03-01

    Effects of contaminants on communities are difficult to assess and poorly understood. We analyzed in situ effects of trace metals and common environmental variables on benthic macroinvertebrate communities in floodplain lakes. Alternative measures of trace metal availability were evaluated, including total metals, metals normalized on organic carbon (OC) or clay, simultaneously extracted metals (SEM), combinations of SEM and acid-volatile sulfide (AVS), and metals accumulated by detritivore invertebrates (Oligochaeta). Accumulated metal concentrations correlated positively with sediment trace metals and negatively with surface water dissolved OC. Sixty-eight percent of the variation in benthic community composition was explained by a combination of 11 environmental variables, including sediment, water, and morphological characteristics with trace metals. Metals explained 2 to 6% of the community composition when SEM-AVS or individual SEM concentrations were regarded. In contrast, total, normalized, and accumulated metals were not significantly linked to community composition. We conclude that examination of SEM or SEM - AVS concentrations is useful for risk assessment of trace metals on the community level. PMID:15285361

  11. Advanced Gasification Mercury/Trace Metal Control with Monolith Traps

    SciTech Connect

    Michael L. Swanson; Grant E. Dunham; Mark A. Musich

    2007-02-01

    Three potential additives for controlling mercury emissions from syngas at temperatures ranging from 350 to 500 F (177 to 260 C) were developed. Current efforts are being directed at increasing the effective working temperature for these sorbents and also being able to either eliminate any potential mercury desorption or trying to engineer a trace metal removal system that can utilize the observed desorption process to repeatedly regenerate the same sorbent monolith for extended use. Project results also indicate that one of these same sorbents can also successfully be utilized for arsenic removal. Capture of the hydrogen selenide in the passivated tubing at elevated temperatures has resulted in limited results on the effective control of hydrogen selenide with these current sorbents, although lower-temperature results are promising. Preliminary economic analysis suggests that these Corning monoliths potentially could be more cost-effective than the conventional cold-gas (presulfided activated carbon beds) technology currently being utilized. Recent Hg-loading results might suggest that the annualized costs might be as high as 2.5 times the cost of the conventional technology. However, this annualized cost does not take into account the significantly improved thermal efficiency of any plant utilizing the warm-gas monolith technology currently being developed.

  12. Trace metal accumulation in sediments and benthic macroinvertebrates before and after maintenance of a constructed wetland.

    PubMed

    O'Connor, Thomas P; Muthukrishnan, Swarna; Barshatzky, Kristen; Wallace, William

    2012-04-01

    Stormwater best management practices (BMPs) require regular maintenance. The impact on trace metal concentrations in a constructed stormwater wetland BMP on Staten Island, New York, was investigated by analyzing sediment concentrations and tissue residues of the dominant macroinvertebrates (Tubifex tubifex) prior and subsequent to maintenance. Trace metal concentrations were assessed using standard serial extraction (for sediment) and acid digestion (for tissue burdens) techniques, followed by quantitative determination using graphite furnace atomic absorption spectrometry and inductively coupled plasma optical emission spectrometry, respectively. The results suggest that disturbance of sediment during maintenance of the BMP resulted in an increase in the most mobile fraction of trace metals, especially those associated with finer grained sediments (< 63 tm), and as a consequence, measured metal concentrations in macroinvertebrates increased. Regressions of a subset of metal concentrations (copper, lead, and zinc) in sediment and the macroinvertebrate tissue burden samples generally increased as a result of maintenance. A follow-up sampling event 9 months after maintenance demonstrated that the most readily available form of trace metal in the BMP was reduced, which supports (1) long-term sequestration of metals in the BMP and (2) that elevated bioavailability following maintenance was potentially a transient feature of the disturbance. This study suggests that in the long-term, performing sediment removal might help reduce bioavailability of trace metal concentrations in both the BMP and the receiving water to which a BMP discharges. However, alternative practices might need to be implemented to reduce trace metal bioavailability in the short-term. PMID:22834226

  13. Distribution and Potential Toxicity of Trace Metals in the Surface Sediments of Sundarban Mangrove Ecosystem, Bangladesh

    NASA Astrophysics Data System (ADS)

    Kumar, A.; Ramanathan, A.; Mathukumalli, B. K. P.; Datta, D. K.

    2014-12-01

    The distribution, enrichment and ecotoxocity potential of Bangladesh part of Sundarban mangrove was investigated for eight trace metals (As, Cd, Cr, Cu, Fe, Mn, Pb and Zn) using sediment quality assessment indices. The average concentration of trace metals in the sediments exceeded the crustal abundance suggesting sources other than natural in origin. Additionally, the trace metals profile may be a reflection of socio-economic development in the vicinity of Sundarban which further attributes trace metals abundance to the anthropogenic inputs. Geoaccumulation index suggests moderately polluted sediment quality w.r.t. Ni and As and background concentrations for Al, Fe, Mn, Cu, Zn, Pb, Co, As and Cd. Contamination factor analysis suggested low contamination by Zn, Cr, Co and Cd, moderate by Fe, Mn, Cu and Pb while Ni and As show considerable and high contamination, respectively. Enrichment factors for Ni, Pb and As suggests high contamination from either biota or anthropogenic inputs besides natural enrichment. As per the three sediment quality guidelines, Fe, Mn, Cu, Ni, Co and As would be more of a concern with respect to ecotoxicological risk in the Sundarban mangroves. The correlation between various physiochemical variables and trace metals suggested significant role of fine grained particles (clay) in trace metal distribution whereas owing to low organic carbon content in the region the organic complexation may not be playing significant role in trace metal distribution in the Sundarban mangroves.

  14. Trace and ultratrace metals in bottled waters: survey of sources worldwide and comparison with refillable metal bottles.

    PubMed

    Krachler, Michael; Shotyk, William

    2009-01-15

    Bottled waters from diverse natural and industrial sources are becoming increasingly popular worldwide. Several potentially harmful trace metals (Ag, Be, Li, Ge, Sb, Sc, Te, Th, U) are not monitored regularly in such waters. As a consequence, there is extremely limited data on the abundance and potential health impacts of many potentially toxic trace elements. Containers used for the storage of bottled waters might also increase trace metal levels above threshold limits established for human consumption by the EPA or WHO. Applying strict clean room techniques and sector field ICP-MS, 23 elements were determined in 132 brands of bottled water from 28 countries. In addition, leaching experiments with high purity water and various popular metal bottles investigated the release of trace metals from these containers. The threshold limits for elements such as Al, Be, Mn and U in drinking water were clearly exceeded in some waters. Several bottled waters had Li concentrations in the low mg/L range, a level which is comparable to blood plasma levels of patients treated against manic depression with Li-containing drugs. The rate of release of trace metals from metal bottles assessed after 13 days was generally low, with one exception: Substantial amounts of both Sb and Tl were released from a commercially available pewter pocket flask, exceeding international guidelines 5- and 11-fold, respectively. Trace metal levels of most bottled waters are below guideline levels currently considered harmful for human health. The few exceptions that exist, however, clearly reveal that health concerns are likely to manifest through prolonged use of such waters. The investigated coated aluminium and stainless steel bottles are harmless with respect to leaching of trace metals into drinking water. Pocket flasks, in turn, should be selected with great care to avoid contamination of beverages with harmful amounts of potentially toxic trace metals such as Sb and Tl. PMID:18990431

  15. Source and Cycling of Trace Metals and Nutrients in a Microbial Coalbed Methane System

    NASA Astrophysics Data System (ADS)

    Earll, M. M.; Barnhart, E. P.; Ritter, D.; Vinson, D. S.; Orem, W. H.; Vengosh, A.; McIntosh, J. C.

    2015-12-01

    The source and cycling of trace metals and nutrients in coalbed methane (CBM) systems are controlled by both geochemical processes, such as dissolution or precipitation, and biological mediation by microbial communities. CBM production by the microbes is influenced by trace metals and macronutrients such as nitrogen (N) and phosphate (P). Previous studies have shown the importance of these nutrients to both enhance and inhibit methane production; however, it's not clear whether they are sourced from coal via in-situ biodegradation of organic matter or transported into the seams with groundwater recharge. To address this knowledge gap, trace metal and nutrient geochemistry and the organic content of solid coal and associated groundwater will be investigated across a hydrologic gradient in CBM wells in the Powder River Basin, MT. Sequential dissolution experiments (chemical extraction of organic and inorganic constituents) using 8 core samples of coal and sandstone will provide insight into the presence of trace metals and nutrients in coalbeds, the associated minerals present, and their mobilization. If significant concentrations of N, P, and trace metals are present in core samples, in-situ sourcing of nutrients by microbes is highly probable. The biogeochemical evolution of groundwater, as it relates to trace metal and nutrient cycling by microbial consortia, will be investigated by targeting core-associated coal seams from shallow wells in recharge areas to depths of at least 165 m and across a 28 m vertical profile that include overburden, coal, and underburden. If microbial-limiting trace metals and nutrients are transported into coal seams with groundwater recharge, we would expect to see higher concentrations of trace metals and nutrients in recharge areas compared to deeper coalbeds. The results of this study will provide novel understanding of where trace metals and nutrients are sourced and how they are cycled in CBM systems.

  16. Trace metal retention in mangrove ecosystems in Guanabara Bay, SE Brazil.

    PubMed

    Machado, W; Silva-Filho, E V; Oliveira, R R; Lacerda, L D

    2002-11-01

    Along contrasting environmental conditions (e.g., degree of trace metal contamination and mangrove forest structural development), sediments of Laguncularia racemosa-dominated mangrove stands in Guanabara Bay (SE Brazil) presented a trend of trace metal accumulation in forms with low potential of remobilization and biotic uptake. Concurrently, a relatively low transfer of sediment-bound metals to L. racemosa leaves was observed, which may moderate the metal export from the forests via leaf litter transport and the metal availability to enter in food chains based on leaf consumption. PMID:12523527

  17. Trace and Essential Elements Analysis in Cymbopogon citratus (DC.) Stapf Samples by Graphite Furnace-Atomic Absorption Spectroscopy and Its Health Concern.

    PubMed

    Anal, Jasha Momo H

    2014-01-01

    Cymbopogon citratus (DC.) Stapf commonly known as lemon grass is used extensively as green tea and even as herbal tea ingredient across the world. Plants have the ability to uptake metals as nutrient from the soil and its environment which are so essential for their physiological and biochemical growth. Concentrations of these twelve trace elements, namely, Mg, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Mo, As, Cd, and Pb, are analysed by graphite furnace-atomic absorption spectroscopy (GF-AAS) and are compared with the permissible limits of FAO/WHO, ICMR, and NIH, USA, which are found to be within permissible limits. Toxic metals like As, Cd, and Pb, analysed are within the tolerable daily diet limit and at low concentration. PMID:25525430

  18. Trace and Essential Elements Analysis in Cymbopogon citratus (DC.) Stapf Samples by Graphite Furnace-Atomic Absorption Spectroscopy and Its Health Concern

    PubMed Central

    Anal, Jasha Momo H.

    2014-01-01

    Cymbopogon citratus (DC.) Stapf commonly known as lemon grass is used extensively as green tea and even as herbal tea ingredient across the world. Plants have the ability to uptake metals as nutrient from the soil and its environment which are so essential for their physiological and biochemical growth. Concentrations of these twelve trace elements, namely, Mg, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Mo, As, Cd, and Pb, are analysed by graphite furnace-atomic absorption spectroscopy (GF-AAS) and are compared with the permissible limits of FAO/WHO, ICMR, and NIH, USA, which are found to be within permissible limits. Toxic metals like As, Cd, and Pb, analysed are within the tolerable daily diet limit and at low concentration. PMID:25525430

  19. Microbial Influences on Trace Metal Cycling in a Meromictic Lake, Fayetteville Green Lake, NY

    NASA Astrophysics Data System (ADS)

    Zerkle, A. L.; House, C.; Kump, L.

    2002-12-01

    Microorganisms can exist in aquatic environments at very high cell densities of up to 1011 cells/L, and can accumulate significant quantities of trace metals. Bacteria actively take up bioactive trace metals, including Fe, Zn, Mn, Co, Ni, Cu, and Mo, which function as catalytic centers in metalloproteins and metal-activated enzymes involved in virtually all cellular functions. In addition, bacteria may catalyze the release of trace metals from inorganic substrates by processes such as the reduction of iron and manganese oxides, suggesting that trace metal distributions within a natural environment dominated by microbial processes may be controlled primarily by microbial ecology. Fayetteville Green Lake (FGL), NY, is a permanently stratified meromictic lake that has a well-oxygenated surface water mass (mixolimnion) overlying a relatively stagnant, anoxic deep water mass (monimolimnion). A chemocline separates the water masses at around 20m depth, where oxygen concentrations decrease and sulfate and methane concentrations increase. In addition, previous studies have indicated that trace metals such as V, Cr, Co, Mn, and Fe reach elevated concentrations at the chemocline. Using fluorescent in situ hybridization (FISH) of FGL samples from depths of up to 40m with bacterial and archaeal probes, we have shown that fluctuating redox conditions within the FGL water column correlate with significant variations in the composition and distribution of microbial populations with depth. The mixolimnion is dominated by Eubacteria, with increasing concentrations of Archaea in the lower anoxic zone. Increases in microbial cell densities coincide with increases in trace metals at the chemocline, suggesting microbial activity may be responsible for trace metal release at this boundary. 16S rRNA PCR cloning techniques are currently being used to identify dominant microbial populations at various levels within the FGL water column. Future studies will focus on the potential for these

  20. Geochronology and historical deposition of trace metals in three tropical estuaries in the Gulf of Guinea

    NASA Astrophysics Data System (ADS)

    Mahu, Edem; Nyarko, Elvis; Hulme, Samuel; Swarzenski, Peter; Asiedu, Daniel K.; Coale, Kenneth H.

    2016-08-01

    The depositional histories of trace metals (Pb, Cu, and Zn) in sediment cores from three Ghanaian estuaries were reconstructed using radioisotope-derived (210Pb and 137Cs) geochronologies. A core collected from each of the Amisa, Sakumo II and Volta estuaries was analyzed for trace metals and radionuclides. Lead-210 and 137Cs dating via gamma spectroscopy, and trace metal analysis via inductively coupled plasma mass spectrometry (ICP-MS) were used in deriving sedimentation rates, geochronologies and accumulation trends of trace metals. The sedimentation rates in all three estuaries (in the range of 0.54-0.83 cm yr-1) were greater than the predicted sea level rise (∼0.33 cm yr-1) for the Accra Coast of Ghana. The 210Pb depositional rates of 6.83 dpm cm-2 y-1, 2.74 dpm cm-2 y-1 and 1.75 dpm cm-2 y-1 estimated for the Amisa, Sakumo II and Volta estuaries, respectively, are higher than those recorded in other latitudes. Trace metal analysis revealed differences in the concentrations of Cu, Pb and Zn between deeper and surficial layers of each core to be in the range of 10-20%, which is well within the natural variations attributed to geochemical factors. Relative to the Amisa and Volta estuaries, the temporal profiles of Al-normalized metal concentrations and estimated fluxes suggest anthropogenic processes augmented the natural fluxes of trace metals, particularly Zn into the Sakumo II estuary during the last 7 years.

  1. Presence of trace metals in aquaculture marine ecosystems of the northwestern Mediterranean Sea (Italy).

    PubMed

    Squadrone, S; Brizio, P; Stella, C; Prearo, M; Pastorino, P; Serracca, L; Ercolini, C; Abete, M C

    2016-08-01

    Information regarding chemical pollutant levels in farmed fish and shellfish, along with the risks associated with their consumption is still scarce. This study was designed to assess levels of exposure to 21 trace elements in fish (Dicentrarchus labrax), mussels (Mytilus galloprovincialis) and oysters (Crassostrea gigas) collected from aquaculture marine ecosystems of the northwestern Mediterranean Sea. Metal concentrations showed great variability in the three species; the highest values of the nonessential elements As and Cd were found in oysters while the highest levels of Al, Pb and V were found in mussels. The essential elements Cu, Mn and Zn were highest in oysters, but Fe, Cr, Ni, Se, Co and Mo levels were highest in mussels. Fish had the lowest concentrations for all trace elements, which were at least one order of magnitude lower than in bivalves. The rare earth elements cerium and lanthanum were found at higher levels in mussels than in oysters, but undetectable in fish. The maximum values set by European regulations for Hg, Cd and Pb were never exceeded in the examined samples. However, comparing the estimated human daily intakes (EHDIs) with the suggested tolerable copper and zinc intakes suggested a potential risk for frequent consumers of oysters. Similarly, people who consume high quantities of mussels could be exposed to concentrations of Al that exceed the proposed TWI (tolerable weekly intake). PMID:27179326

  2. Trace metal distribution in sediments of northern continental shelf of Crete Island, Eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Poulos, S. E.; Dounas, C. G.; Alexandrakis, G.; Koulouri, P.; Drakopoulos, P.

    2009-08-01

    The present study investigates the distribution of trace metals (Zn, Hg, Cd, Cu, and Pb), as indicators of pollution, in the surficial offshore shelf sediments along the northern coast of Heraklion Prefecture (Crete, Mediterranean Sea). The concentrations and the spatial distribution of the different trace metals, in relation to the sedimentological characteristics and the water circulation pattern of the entire continental shelf, are associated with human inshore sources of pollutants located along the coastline of the study area. Although the trace metal concentrations measured are higher than the background values, they are not considered to be dangerous to human health, as they are lower than the standard values given by the World Health Organisation, with only a few localised exceptions. Furthermore, results reveal the important role of local hydrodynamism that moves fine-grained material and associated trace metals offshore (seawards to wave breaking zone) and then transports them eastwards by entrapping them in the prevailing offshore shelf-water circulation.

  3. EVALUATION OF SAMPLING AND FIELD FILTRATION METHODS FOR THE ANALYSIS OF TRACE METALS IN GROUND WATER

    EPA Science Inventory

    Selected groundwater sampling and filtering methods were evaluated to determine their effects on field parameters and trace metal concentrations in samples collected under several types of field conditions. he study focused on sampling in conventional standpipe monitoring wells u...

  4. Characterizing the Environmental Availability of Trace Metals in Savannah River Site Soils

    SciTech Connect

    Serkiz, S.M.

    1999-03-18

    An eight step sequential extraction technique was used to characterize the environmental availability of trace metals from background and waste site soil samples collected from the US Department of Energy's Savannah River Site (SRS).

  5. TRACE ELEMENT CHEMISTRY IN RESIDUAL-TREATED SOIL: KEY CONCEPTS AND METAL BIOAVAILABILITY

    EPA Science Inventory

    Trace element solubility and availability in land-applied residuals is governed by fundamental chemical reactions between metal constituents, soil, and residual components. Iron, aluminum, and manganese oxides; organic matter; and phosphates, carbonates, and sulfides are importan...

  6. Bioaccumulation and toxicity of heavy metals and related trace elements

    SciTech Connect

    Murphy, C.B.; Speigel, S.J.

    1983-06-01

    A literature review of bioaccumulation and toxicity of heavy metals is presented. The most common heavy metals studied were Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Ag, Cd, Sn, Hg, and Pb. The studies dealt with heavy metals in the environment, bioconcentration, toxicity, and detoxification of heavy metals. (JMT)

  7. Distribution of trace impurities of metals during their adsorption from solutions of phosphoric acid

    SciTech Connect

    Toranov, A.N.; Evseeva, N.K.; Kremenskaya, I.N.

    1986-09-01

    The phase distribution of trace impurities of metals between solutions of phosphoric acid and a polymer adsorbent based on a copolymer of styrene with divinylbenzene, impregnated with di-2-ethylhexyldithiophosphoric acid, was investigated. The influence of the composition of the aqueous and solid phases on the distribution coefficients of trace impurities of metals is discussed. It was shown that the coefficients of interfacial distribution in the case of adsorption by an impregnated adsorbent is higher than in the case of liquid extraction.

  8. Effects of trace metal ions on secondary metabolism and the morphological development of streptomycetes.

    PubMed

    Locatelli, Fabricio M; Goo, Kian-Sim; Ulanova, Dana

    2016-05-01

    Bacteria belonging to the Streptomyces genus are characterized by a complex life cycle and the production of many bioactive secondary metabolites. Trace metals play an important role in streptomycete metabolism and development, however, their mechanism of action is not fully understood. In this review, we summarize the present knowledge on metallosensing regulators and trace metal action, as well as discuss the possible application in natural product discovery. PMID:27110673

  9. Facilitation Drives the Positive Effects of Plant Richness on Trace Metal Removal in a Biodiversity Experiment

    PubMed Central

    Wang, Jiang; Ge, Yuan; Chen, Tong; Bai, Yi; Qian, Bao Ying; Zhang, Chong Bang

    2014-01-01

    Background Phytoextraction is an environmentally acceptable and inexpensive technique for mine tailing rehabilitation that uses metallophyte plants. These plants reduce the soil trace metal contents to environmentally acceptable levels by accumulating trace metals. Recently, whether more trace metals can be removed by species-rich communities of these plants received great attention, as species richness has been reported having positive effects on ecosystem functions. However, how the species richness affects trace metals removal of plant communities of mine tailing is rarely known. Methodology/Principal Findings We examined the effects of species richness on soil trace metal removal in both natural and experimental plant communities. The root lengths and stem heights of each plant species were measured in order to calculate the functional diversity indices. Our results showed that trace metal (Cu, Cd, Pb and Zn) concentrations in mine tailing soil declined as species richness increased in both the natural and experimental plant communities. Species richness, rather than functional diversity, positively affected the mineralomass of the experimental plant communities. The intensity of plant-plant facilitation increased with the species richness of experimental communities. Due to the incremental role of plant-plant facilitation, most of the species had higher biomasses, higher trace metal concentrations in their plant tissues and lower malondialdehyde concentrations in their leaves. Consequently, the positive effects of species richness on mineralomass were mostly attributable to facilitation among plants. Conclusions/Significance Our results provide clear evidence that, due to plant-plant facilitation, species richness positively affects the removal of trace metals from mine tailing soil through phytoextraction and provides further information on diversity conservation and environmental remediation in a mine tailing environment. PMID:24695538

  10. Essential, trace and toxic element concentrations in the liver of the world's largest bony fish, the ocean sunfish (Mola mola).

    PubMed

    Perrault, Justin R; Buchweitz, John P; Lehner, Andreas F

    2014-02-15

    No studies document essential (calcium, magnesium, phosphorus, potassium, sodium), trace (barium, boron, chromium, cobalt, copper, iron, manganese, molybdenum, selenium, zinc) or toxic element (antimony, arsenic, cadmium, lead, mercury, thallium) concentrations in any members of the family Molidae, including the world's largest bony fish, the ocean sunfish (Mola mola). Here, we analyzed 21 elements in the liver of one M. mola. These values were compared to liver concentrations in multiple species with spatial and dietary overlap. Concentrations of calcium (3339 ppm wet weight) and iron (2311 ppm wet weight) were extremely elevated in comparison to a number of other fish species, indicating that calcium and/or iron toxicity may have occurred in this animal. Concentrations of toxic elements were generally low, with the exception of cadmium (3.5 ppm). This study represents the first report of essential, trace and toxic elements in this species. PMID:24341944

  11. Trace metals in water, sediment and bivalves of a tropical estuary, west coast of India.

    PubMed

    Parvez Al-Usmani, S M; Jagtap, T G; Patil, D N

    2015-10-15

    Trace metal pollution was studied in water, sediment and three selected bivalves in Mandovi and Chapora estuaries of Goa. The trace metal in water and sediment of Mandovi was higher than in Chapora. The concentration in the tissues was in the range of 1205.2-2506.7 ppm for Paphia malabarica, 1906.2-2802.6 ppm for Perna viridis and 778.7-1607.5 ppm for Saccostrea cucullata in Mandovi estuary. Tha values for Chapora were 199.4-625.8 ppm for P. malabarica, 812.6-1220.2 for P. viridis and 392.5-418.6 ppm for S. cucullata. The anthropogenic input of metal in Mandovi estuary appears to be mainly responsible for the high accumulation of trace metals. These bivalves have potential to serve as indicator for metal contamination in seafood of Goa. PMID:26228069

  12. Insight of EDX analysis and EFTEM: are spherocrystals located in Strombidae digestive gland implied in detoxification of trace metals?

    PubMed

    Volland, Jean-Marie; Lechaire, Jean-Pierre; Frebourg, Ghislaine; Aranda, Dalila Aldana; Ramdine, Gaëlle; Gros, Olivier

    2012-04-01

    Digestive tubules of Strombidae are composed by three cell types: digestive cells, vacuolated cells, and crypt cells. The last one is characterized by the presence of intracellular granules identified as spherocrystals. Such structures are known to occur in basophilic cells of gastropod digestive gland, where they are supposed to be involved in the regulation of some minerals and in detoxification. In this study, energy-dispersive X-ray analysis (EDX) and energy filtered transmission electron microscopy (EFTEM) were used to determine the elemental content of spherocrystals in two Strombidae, Strombus gigas and Strombus pugilis. In freshly collected individuals of both species, the following elements were detected: Ca, Fe, Mg, P, and Zn. Aluminum and Mn were also detected in S. gigas. Their presence in spherocrystals indicates that, in Strombidae, spherocrystals are involved in the regulation of minerals and essential trace metals. In order to answer the question "are spherocrystals involved in nonessential trace metals scavenging?," artificial cadmium and lead exposure by both waterborne and dietary pathways was applied to S. pugilis. No evidence of cadmium (Cd(NO(3))(2)) or lead (Pb(NO(3))(2)) provided by food was found in spherocrystals. Cadmium provided in water (Cd(NO(3))(2) and CdCl(2)) causes structural modifications of the digestive gland; however, this element was not trapped in spherocrystals. These results suggest that spherocrystals are not involved in detoxification of such nonessential trace metals. PMID:21919125

  13. Determination of trace and heavy metals in some commonly used medicinal herbs in Ayurveda.

    PubMed

    Nema, Neelesh K; Maity, Niladri; Sarkar, Birendra K; Mukherjee, Pulok K

    2014-11-01

    Traditionally, the herbal drugs are well established for their therapeutic benefits. Depending upon their geographical sources sometimes the trace and heavy metals' content may differ, which may lead to severe toxicity. So, the toxicological and safety assessment of these herbal drugs are one of the major issues in recent days. Eight different plant species including Aloe vera, Centella asiatica, Calendula officinalis, Cucumis sativus, Camellia sinensis, Clitoria ternatea, Piper betel and Tagetes erecta were selected to determine their heavy and trace metals content and thereby to assure their safer therapeutic application. The trace and heavy metals were detected through atomic absorption spectrometry analysis. The selected medicinal plant materials were collected from the local cultivated regions of West Bengal, India, and were digested with nitric acid and hydrochloric acid as specified. Absorbance was measured through atomic absorption spectrometer (AA 303) and the concentration of different trace and heavy metals in the plant samples were calculated. The quantitative determinations were carried out using standard calibration curve obtained by the standard solutions of different metals. The contents of heavy metals were found to be within the prescribed limit. Other trace metals were found to be present in significant amount. Thus, on the basis of experimental outcome, it can be concluded that the plant materials collected from the specific region are safe and may not produce any harmful effect of metal toxicity during their therapeutic application. The investigated medicinal plants contain trace metals such as copper (Cu), chromium (Cr), manganese (Mn), iron (Fe) and nickel (Ni) as well as heavy metals such as arsenic (As), lead (Pb) and mercury (Hg), which were present within the permissible limit. PMID:23222691

  14. Assessment of diffuse trace metal inputs into surface waters - Combining empirical estimates with process based simulations

    NASA Astrophysics Data System (ADS)

    Schindewolf, Marcus; Steinz, André; Schmidt, Jürgen

    2015-04-01

    As a result of mining activities since the 13th century, surface waters of the German Mulde catchment suffer from deleterious dissolved and sediment attached lead (Pb) and zinc (Zn) inputs. The leaching rate of trace metals with drainage water is a significant criterion for assessing trace metal concentrations of soils and associated risks of ground water pollution. However, the vertical transport rates of trace metals in soils are difficult to quantify. Monitoring is restricted to small lysimeter plots, which limits the transferability of results. Additionally the solid-liquid-transfer conditions in soils are highly variable, primarily due to the fluctuating retention time of percolating soil water. In contrast, lateral sediment attached trace metal inputs are mostly associated with soil erosion and resulting sediment inputs into surface waters. Since soil erosion by water is related to rare single events, monitoring and empirical estimates reveal visible shortcomings. This gap in knowledge can only be closed by process based model calculations. Concerning these calculations it has to be considered, that Pb and Zn are predominantly attached to the fine-grained soil particles (<0.063 mm). The selective nature of soil erosion causes a preferential transport of these fine particles, while less contaminated larger particles remain on site. Consequently trace metals are enriched in the eroded sediment compared to the origin soil. This paper aims to introduce both, a new method that allows the assessment of trace metal leaching rates from contaminated top soils for standardised transfer conditions and a process based modelling approach for sediment attached trace metal inputs into surface waters. Pb and Zn leaching rates amounts to 20 Mg ha-1 yr-1 resp. 114 Mg ha-1 yr-1. Deviations to observed dissolved trace metal yields at the Bad Düben gauging station are caused by plant uptake and subsoil retention. Sediment attached Pb and Zn input rates amounts to 114 Mg ha-1 yr

  15. Depuration effects on trace metals in Anomalocardia brasiliana (Gmelin, 1791)

    SciTech Connect

    Wallner-Kersanach, M. ); Lobo, S.E.; Silva, E.M. da )

    1994-06-01

    Bivalves have been regarded as suitable bioindicators of metal pollution in the marine and estuarine environments. However, the metal concentrations of the soft parts of individual bivalves can vary considerably depending on size variations, geographic and genetic differences, individual variability in metal uptake, ingestion of sediment particles and induction of metal-binding proteins. Metal-containing particulate matter in the gut can also be significant. These authors showed that if deputation is not carried out, then large variations in metal concentrations are more likely to occur. In the Todos os Santos Bay on the northeastern coast of Brazil, the cockle A. brasiliana is the most abundant bivalve and is well adapted to area conditions. An important source of food for many local communities, this species has been frequently used as an indicator for heavy metals pollution; however, no data have been published on metal concentrations of A. brasiliana of different size classes and on the effects of deputation on overall concentration. It is therefore important to determine the metal concentrations in A. brasiliana both from the point of view of how the concentrations relate to metal loading of the area. The effect of size upon metal concentration of shellfish has been examined by Boyden, who found that zinc in Mytilus edulis was greater in smaller individuals while cadmium was independent of size. The objective of this study was to determine concentrations of copper, zinc, cadmium and lead in A. brasiliana collected from a site with a relatively low impact of heavy metal contamination, to examine metals in different size classes and to assess the effect of depuration on tissue concentration of the metals. These elements were selected due to their toxicity to marine organisms, when their excess as free metal may interact with cell structures and/or enzymes affecting metabolic activities. 22 refs., 2 figs., 2 tabs.

  16. In situ redeposition of trace metals mobilized by CO2-charged brines

    NASA Astrophysics Data System (ADS)

    Wigley, M.; Kampman, N.; Chapman, H. J.; Dubacq, B.; Bickle, M. J.

    2013-05-01

    Mobilization of contaminants by CO2-charged brines is one concern relating to injection of CO2 as part of carbon capture and storage projects. This study monitors the mobility of trace metals in an exhumed CO2-charged aquifer near the town of Green River, Utah (USA), where CO2-charged brines have bleached red sandstones, and concentrated trace metals at the bleaching reaction front. Mass balance calculations on the trace metal enrichments are used to calculate time-integrated fluid fluxes and show that a significant fraction of the metals mobilized by the CO2-rich brines are redeposited locally. A sequential extraction procedure on metal-enriched samples shows that these metals are incorporated into secondary carbonate and oxide phases which have been shown to grow at the CO2-promoted bleaching reaction front. We argue that while CO2-charged brines are capable of mobilizing trace metals, local metal redeposition implies that the potential for contamination of overlying freshwater aquifers is low.

  17. Trace Metals in the Early Ocean, Biological Implications, and Evolving Biospheric Redox

    NASA Astrophysics Data System (ADS)

    Lyons, T. W.; Scott, C.; Gill, B. C.; Anbar, A. D.

    2008-12-01

    Dissolved molybdenum abounds in modern, oxygen-rich seawater as the highly soluble molybdate ion. But this trace metal, also a nutrient essential to phytoplankton productivity, was not always so readily available. Several periods of the geologic past are noted for being euxinic (i.e., oxygen-poor and sulfide-rich) at regional or perhaps even global scales. During the Proterozoic in particular, numerous euxinic settings may have persisted in the ocean for a billion years or more following the initial rise of oxygen in the atmosphere. Under such conditions, Mo is sequestered efficiently, and corresponding limitation in the oceanic inventory may have impacted nitrogen fixation by prokaryotes, as well as uptake of fixed nitrogen by early eukaryotes. Mo is essential for nitrogen fixation and nitrate assimilation as a cofactor for nitrogenase and assimilatory nitrate reductase enzymes, respectively. Evidence for analogous limitations is emerging for portions of the Paleozoic and Mesozoic, but the potential impacts have not yet been considered. In each case, the critical arguments hang on our ability (1) to estimate oceanic extents of oxygen-poor, sulfide-rich settings for the time slice of interest and (2) to discriminate Mo drawdown in the global ocean from that occurring locally within individual basins. Traditional and emerging approaches for distinguishing local from global ancient anoxia/euxinia will be highlighted with an eye toward estimating the impact on availability of Mo and other bioessential, redox-sensitive transition metals. The context for this exploration will be the long history of evolving redox in the ocean and atmosphere from the Archean forward. The Phanerozoic examples are also associated with major biotic extinction events, and our understanding of the relationships among the primary drivers of extinction, widespread euxinic conditions, and the impact of micronutrient availability during extinction and recovery remains nascent.

  18. Distribution and pollution assessment of trace metals in seawater and sediment in Laizhou Bay

    NASA Astrophysics Data System (ADS)

    Lü, Dongwei; Zheng, Bing; Fang, Yan; Shen, Ge; Liu, Huijun

    2015-07-01

    Selected trace metals (Pb, Cd, Cu, Hg) and arsenic in seawater and surface sediments of Laizhou Bay were determined, to evaluate their spatial distribution, pollution risk and potential ecological risk. Concentrations of the elements were 0.56-2.07, 0.14-0.38, 12.70-18.40, 0.014-0.094, and 1.13-2.37 μg/L in the seawater and 8.94-32.2, 0.18-0.67, 4.51-30.5, 0.006-0.058, and 5.75-15.3 mg/kg in sediments for Pb, Cd, Cu, Hg and As, respectively. High concentrations of the trace metals and arsenic in seawater and surface sediments were generally observed near the river estuary. The pollution risk result of the elements showed that Cu was the prominent trace metal pollutant in seawater, followed by Hg, Pb, Cd and As. The metal complex pollution index in seawater was at a medium level. The most important trace metal pollutant in sediments was Cd, followed by As, Cu, Pb, and Hg. Our pollution assessment suggests that trace metal pollution in Laizhou Bay sediments was at a low level. The potential ecological risk was also low in surface sediment.

  19. Modelling of trace metal uptake by roots taking into account complexation by exogenous organic ligands

    NASA Astrophysics Data System (ADS)

    Jean-Marc, Custos; Christian, Moyne; Sterckeman, Thibault

    2010-05-01

    The context of this study is phytoextraction of soil trace metals such as Cd, Pb or Zn. Trace metal transfer from soil to plant depends on physical and chemical processes such as minerals alteration, transport, adsorption/desorption, reactions in solution and biological processes including the action of plant roots and of associated micro-flora. Complexation of metal ions by organic ligands is considered to play a role on the availability of trace metals for roots in particular in the event that synthetic ligands (EDTA, NTA, etc.) are added to the soil to increase the solubility of the contaminants. As this role is not clearly understood, we wanted to simulate it in order to quantify the effect of organic ligands on root uptake of trace metals and produce a tool which could help in optimizing the conditions of phytoextraction.We studied the effect of an aminocarboxilate ligand on the absorption of the metal ion by roots, both in hydroponic solution and in soil solution, for which we had to formalize the buffer power for the metal. We assumed that the hydrated metal ion is the only form which can be absorbed by the plants. Transport and reaction processes were modelled for a system made up of the metal M, a ligand L and the metal complex ML. The Tinker-Nye-Barber model was adapted to describe the transport of solutes M, L and ML in the soil and absorption of M by the roots. This allowed to represent the interactions between transport, chelating reactions, absorption of the solutes at the root surface, root growth with time, in order to simulate metal uptake by a whole root system.Several assumptions were tested such as i) absorption of the metal by an infinite sink and according to a Michaelis-Menten kinetics, solutes transport by diffusion with and without ii) mass flow and iii) soil buffer power for the ligand L. In hydroponic solution (without soil buffer power), ligands decreased the trace metal flux towards roots, as they reduced the concentration of hydrated

  20. ATMOSPHERIC INPUT OF TRACE METALS TO LAKE MICHIGAN

    EPA Science Inventory

    Atmospheric bulk deposition was collected on a monthly basis in the Lake Michigan basin from September 1975 through December 1976 to determine the atmospheric loading of trace elements to Lake Michigan. The sampling network consisted of bulk collectors located at 21 locations in ...

  1. Bioaccessibility of essential and non-essential metals in commercial shellfish from Western Europe and Asia.

    PubMed

    Amiard, Jean-Claude; Amiard-Triquet, Claude; Charbonnier, Laetitia; Mesnil, Aurélie; Rainbow, Philip S; Wang, Wen-Xiong

    2008-06-01

    Maximum acceptable concentrations of metals in food - based on total concentrations - have been established in many countries. To improve risk assessment, it would be better to take into account bioaccessible concentrations. A total of seven species of molluscs from France, UK and Hong Kong was examined in this study including clams, mussels, oysters, scallops and gastropods. The species which have total metal concentrations higher than the most severe food security limits are mainly oysters (all of the three studied species), the gastropod Buccinum undatum for cadmium and zinc, and scallops for cadmium. The lowest bioaccessibility (in % extractability with gut juices) was observed for silver (median for all of the species: 14%), it was moderate for lead (median: 33%) and higher for cadmium, zinc and copper (medians were respectively 54%, 65%, and 70%). In most cases, bioaccessible concentrations remained higher than the safety limits, except for cadmium in scallops and zinc in B. undatum. The influence of feeding habit (masticated or swallowed, addition of vinegar or lemon) on metal bioaccessibility in oysters is limited. On the contrary, cooking the gastropods decreased the bioaccessibility of metals, except silver. PMID:18329777

  2. Spectroscopic characterization of the uptake of essential and xenobiotic metal cations in cells of the soil bacterium Azospirillum brasilense.

    PubMed

    Kamnev, A A; Renou-Gonnord, M F; Antonyuk, L P; Colina, M; Chernyshev, A V; Frolov, I; Ignatov, V V

    1997-01-01

    The results of flame (FAAS) or graphite furnace atomic absorption spectrometric (GFAAS) analyses are presented and discussed on the accumulation of essential metals (Mg, Ca, Mn and Fe contained in the cultivation medium) and traces of each one of the conventionally xenobiotic elements from the group V, Co, Ni, Cu, Zn or Pb, added to the medium in concentrations (0.2 mM) which do not essentially suppress growth of the bacterial culture, in cells of the plant root-associated nitrogen-fixing bacterium Azospirillum brasilense. Along with the essential cations assimilated by the bacterium, Zn and Cu were found to effectively accumulate in the biomass from the environment. The uptake of Co and Ni was significantly less pronounced, whereas Pb and V appeared to be present in cells in much lower concentrations than in the cultivation medium evidently showing no tendency to be assimilated by azospirilla. The effect of the above xenobiotics on the uptake level of the four essential elements provided evidence that they may compete for the formation of biologically active complexes with substances of both intracellular and extracellular localization. The analytical data obtained are compared with Fourier transform infrared (FTIR) spectra of intact vacuum-dried bacterial cells grown in a standard medium and under the conditions of an increased metal uptake. PMID:9043641

  3. Trace Metal Acquisition by Marine Heterotrophic Bacterioplankton with Contrasting Trophic Strategies

    PubMed Central

    Barbeau, Katherine A.

    2016-01-01

    Heterotrophic bacteria in the SAR11 and Roseobacter lineages shape the marine carbon, nitrogen, phosphorous, and sulfur cycles, yet they do so having adopted divergent ecological strategies. Currently, it is unknown whether these globally significant groups partition into specific niches with respect to micronutrients (e.g., trace metals) and how that may affect marine trace metal cycling. Here, we used comparative genomics to identify diverse iron, cobalt, nickel, copper, and zinc uptake capabilities in SAR11 and Roseobacter genomes and uncover surprising unevenness within and between lineages. The strongest predictors for the extent of the metal uptake gene content are the total number of transporters per genome, genome size, total metal transporters, and GC content, but numerous exceptions exist in both groups. Taken together, our results suggest that SAR11 have strongly minimized their trace metal uptake versatility, with high-affinity zinc uptake being a unique exception. The larger Roseobacter genomes have greater trace metal uptake versatility on average, but they also appear to have greater plasticity, resulting in phylogenetically similar genomes having largely different capabilities. Ultimately, phylogeny is predictive of the diversity and extent of 20 to 33% of all metal uptake systems, suggesting that specialization in metal utilization mostly occurred independently from overall lineage diversification in both SAR11 and Roseobacter. We interpret these results as reflecting relatively recent trace metal niche partitioning in both lineages, suggesting that concentrations and chemical forms of metals in the marine environment are important factors shaping the gene content of marine heterotrophic Alphaproteobacteria of the SAR11 and Roseobacter lineages. PMID:26729720

  4. Trace Metal Acquisition by Marine Heterotrophic Bacterioplankton with Contrasting Trophic Strategies.

    PubMed

    Hogle, Shane L; Thrash, J Cameron; Dupont, Chris L; Barbeau, Katherine A

    2016-03-01

    Heterotrophic bacteria in the SAR11 and Roseobacter lineages shape the marine carbon, nitrogen, phosphorous, and sulfur cycles, yet they do so having adopted divergent ecological strategies. Currently, it is unknown whether these globally significant groups partition into specific niches with respect to micronutrients (e.g., trace metals) and how that may affect marine trace metal cycling. Here, we used comparative genomics to identify diverse iron, cobalt, nickel, copper, and zinc uptake capabilities in SAR11 and Roseobacter genomes and uncover surprising unevenness within and between lineages. The strongest predictors for the extent of the metal uptake gene content are the total number of transporters per genome, genome size, total metal transporters, and GC content, but numerous exceptions exist in both groups. Taken together, our results suggest that SAR11 have strongly minimized their trace metal uptake versatility, with high-affinity zinc uptake being a unique exception. The larger Roseobacter genomes have greater trace metal uptake versatility on average, but they also appear to have greater plasticity, resulting in phylogenetically similar genomes having largely different capabilities. Ultimately, phylogeny is predictive of the diversity and extent of 20 to 33% of all metal uptake systems, suggesting that specialization in metal utilization mostly occurred independently from overall lineage diversification in both SAR11 and Roseobacter. We interpret these results as reflecting relatively recent trace metal niche partitioning in both lineages, suggesting that concentrations and chemical forms of metals in the marine environment are important factors shaping the gene content of marine heterotrophic Alphaproteobacteria of the SAR11 and Roseobacter lineages. PMID:26729720

  5. Seawater-induced mobilization of trace metals from mackinawite-rich estuarine sediments.

    PubMed

    Wong, Vanessa N L; Johnston, Scott G; Burton, Edward D; Bush, Richard T; Sullivan, Leigh A; Slavich, Peter G

    2013-02-01

    Benthic sediments in coastal acid sulfate soil (CASS) drains can contain high concentrations (~1-5%) of acid volatile sulfide (AVS) as nano-particulate mackinawite. These sediments can sequester substantial quantities of trace metals. Because of their low elevation and the connectivity of drains to estuarine channels, these benthic sediments are vulnerable to rapid increases in ionic strength from seawater incursion by floodgate opening, floodgate failure, storm surge and seasonal migration of the estuarine salt wedge. This study examines the effect of increasing seawater concentration on trace metal mobilization from mackinawite-rich drain sediments (210-550 μmol g⁻¹ AVS) collected along an estuarine salinity gradient. Linear combination fitting of S K-edge XANES indicated mackinawite comprised 88-96% of sediment-bound S. Anoxic sediment suspensions were conducted with seawater concentrations ranging from 0% to 100%. We found that mobilization of some metals increased markedly with increasing ionic strength (Cu, Fe, Mn, Ni) whereas Al mobilization decreased. The largest proportion of metals mobilized from the labile metal pool, operationally defined as Σexchangeable + acid-extractable + organically-bound metals, occurred in sediments from relatively fresh upstream sites (up to 39% mobilized) compared to sediments sourced from brackish downstream sites (0-11% mobilized). The extent of relative trace metal desorption generally followed the sequence Mn > Ni ≈ Cu > Zn > Fe > Al. Trace metal mobilization from these mackinawite-rich sediments was attributed primarily to desorption of weakly-bound metals via competitive exchange with marine-derived cations and enhanced complexation with Cl⁻ and dissolved organic ligands. These results have important implications for trace metal mobilization from these sediments at near-neutral pH under current predicted sea-level rise and climate change scenarios. PMID:23199454

  6. Perirhinal and Postrhinal, but Not Lateral Entorhinal, Cortices Are Essential for Acquisition of Trace Eyeblink Conditioning

    ERIC Educational Resources Information Center

    Suter, Eugenie E.; Weiss, Craig; Disterhoft, John F.

    2013-01-01

    The acquisition of temporal associative tasks such as trace eyeblink conditioning is hippocampus-dependent, while consolidated performance is not. The parahippocampal region mediates much of the input and output of the hippocampus, and perirhinal (PER) and entorhinal (EC) cortices support persistent spiking, a possible mediator of temporal…

  7. Mechanisms of enhanced mobilisation of trace metals by anionic surfactants in soil.

    PubMed

    Hernández-Soriano, Maria del Carmen; Degryse, Fien; Smolders, Erik

    2011-03-01

    Long-term applications of small concentrations of surfactants in soil via wastewater irrigation or pesticide application may enhance trace metal solubility. Mechanisms by which anionic surfactants (Aerosol 22, SDS and Biopower) affect trace metal solubility were assessed using batch, incubation and column experiments. In batch experiments on seven soils, the concentrations of Cu, Cd, Ni and Zn in the dissolved fraction of soils increased up to 100-fold at the high application rates, but increased less than 1.5-fold below the critical micelle concentration. Dissolved metal concentrations were less than 20% affected by surfactants in long-term incubations (70 days) up to the largest dose of 200 mg C kg(-1) soil. Leaching soil columns with A22 (100-1000 mg C L(-1)) under unsaturated conditions increased trace metal concentrations in the leachates 2-4 fold over the control. Correlation analysis and speciation modelling showed that the increased solubility of metals upon surfactant application was more related to the solubilisation of soil organic matter from soil than to complexation of the metals with the surfactant. Organic matter from soil was solubilised in response to a decrease of solution Ca(2+) as a result of Ca-surfactant precipitation. At environmentally relevant concentrations, surfactant application is unlikely to have a significant effect on trace metal mobility. PMID:21163562

  8. N- myc oncogene amplification is correlated to trace metal concentrations in neuroblastoma cultured cells

    NASA Astrophysics Data System (ADS)

    Gouget, B.; Sergeant, C.; Benard, J.; Llabador, Y.; Simonoff, M.

    2000-10-01

    N- myc oncogene amplification is a powerful predictor of aggressive behavior of neuroblastoma (NB), the most common solid tumor of the early childhood. Since N- myc overexpression - subsequent to amplification - determines a phenotype of invasiveness and metastatic spreading, it is assumed that N- myc amplified neuroblasts synthesize zinc metalloenzymes leading to tumor invasion and formation of metastases. In order to test a possible relation between N- myc oncogene amplification and trace metal contents in human NB cells, Fe, Cu and Zn concentrations have been measured by nuclear microprobe analysis in three human neuroblastoma cell lines with various degrees of N- myc amplification. Elemental determinations show uniform distribution of trace metals within the cells, but variations of intracellular trace metal concentrations with respect to the degree of N- myc amplification are highly dependent on the nature of the element. Zinc concentration is higher in both N- myc amplified cell lines (IMR-32 and IGR-N-91) than in the non-amplified cells (SK-N-SH). In contrast, intracellular iron content is particularly low in N- myc amplified cell lines. Moreover, copper concentrations showed an increase with the degree of N- myc amplification. These results indicate that a relationship exists between intracellular trace metals and N- myc oncogene amplification. They further suggest that trace metals very probably play a determinant role in mechanisms of the neuroblastoma invasiveness.

  9. Preservation of NOM-metal complexes in a modern hyperalkaline stalagmite: Implications for speleothem trace element geochemistry

    NASA Astrophysics Data System (ADS)

    Hartland, Adam; Fairchild, Ian J.; Müller, Wolfgang; Dominguez-Villar, David

    2014-03-01

    We report the first quantitative study of the capture of colloidal natural organic matter (NOM) and NOM-complexed trace metals (V, Co, Cu, Ni) in speleothems. This study combines published NOM-metal dripwater speciation measurements with high-resolution laser ablation ICPMS (LA-ICPMS) and sub-annual stable isotope ratio (δ18O and δ13C), fluorescence and total organic carbon (TOC) analyses of a fast-growing hyperalkaline stalagmite (pH ˜11) from Poole’s Cavern, Derbyshire UK, which formed between 1997 and 2008 AD. We suggest that the findings reported here elucidate trace element variations arising from colloidal transport and calcite precipitation rate changes observed in multiple, natural speleothems deposited at ca. pH 7-8. We find that NOM-metal(aq) complexes on the boundary between colloidal and dissolved (˜1 nm diameter) show an annual cyclicity which is inversely correlated with the alkaline earth metals and is explained by calcite precipitation rate changes (as recorded by kinetically-fractionated stable isotopes). This relates to the strength of the NOM-metal complexation reaction, resulting in very strongly bound metals (Co in this system) essentially recording NOM co-precipitation (ternary complexation). More specifically, empirical partition coefficient (Kd) values between surface-reactive metals (V, Co, Cu, Ni) [expressed as ratio of trace element to Ca ratios in calcite and in solution] arise from variations in the ‘free’ fraction of total metal in aqueous solution (fm). Hence, differences in the preservation of each metal in calcite can be explained quantitatively by their complexation behaviour with aqueous NOM. Differences between inorganic Kd values and field measurements for metal partitioning into calcite occur where [free metal] ≪ [total metal] due to complexation reactions between metals and organic ligands (and potentially inorganic colloids). It follows that where fm ≈ 0, apparent inorganic Kd app values are also ≈0, but the

  10. Trace metal accumulation in soil and their phytoavailability as affected by greenhouse types in north China.

    PubMed

    Yang, Lanqin; Huang, Biao; Mao, Mingcui; Yao, Lipeng; Hickethier, Martina; Hu, Wenyou

    2015-05-01

    Long-term heavy organic fertilizer application has linked greenhouse vegetable production (GVP) with trace metal contamination in north China. Given that trace metals release from fertilizers and their availability may be affected by discrepant environmental conditions, especially temperature under different greenhouses, this study investigated Cd, Cu, Pb, and Zn accumulation and contamination extent in soil as well as their phytoavailability under two major greenhouses in Tongshan, north China, namely solar greenhouse (SG) and round-arched plastic greenhouse (RAPG), to evaluate their presumed difference. The results showed significant Cd, Cu, Pb, and Zn accumulation in GVP soil by comparing with those in open-field soil, but their accumulation extent and rates were generally greater in SG than those in RAPG. This may be related to more release of trace metals to soil due to the acceleration of decomposition and humification process of organic fertilizers under higher soil temperature in SG relative to that in RAPG. Overall, soil in both greenhouses was generally less polluted or moderately polluted by the study metals. Similarly, decreased soil pH and elevated soil available metals in SG caused higher trace metals in leaf vegetables in SG than those in RAPG, although there was no obvious risk via vegetable consumption under both greenhouses. Lower soil pH may be predominantly ascribed to more intensive farming practices in SG while elevated soil available metals may be attributed to more release of dissolved organic matter-metal complexes from soil under higher temperature in SG. The data provided in this study may assist in developing reasonable and sustainable fertilization strategies to abate trace metal contamination in both greenhouses. PMID:25422117

  11. Interaction Between Trace Metals, Sodium and Sorbents in Combustion.

    SciTech Connect

    Wendt, O.L.; Davis, S.

    1997-10-17

    The proposed research is directed at an understanding of how to exploit interactions between sodium, toxic metals and sorbents, in order to optimize sorbents injection procedures, which can be used to capture and transform these metals into environmentally benign forms. The research will use a 17kW downflow, laboratory combustor, to yield data that can be interpreted in terms of fundamental kinetic mechanisms. Metals to be considered are lead, cadmium, and arsenic. Sorbents will be kaolinite, bauxite, and limestone. The role of sulfur will also be determined.

  12. Trophic transfer of trace metals: Subcellular compartmentalization in a polychaete and assimilation by a decapod crustacean

    USGS Publications Warehouse

    Rainbow, P.S.; Poirier, L.; Smith, B.D.; Brix, K.V.; Luoma, S.N.

    2006-01-01

    The chemical form of accumulated trace metal in prey is important in controlling the bioavailataility of dietary metal to a predator. This study investigated the trophic transfer of radiolabelled Ag, Cd and Zn from the polychaete worm Nereis diversicolor to the decapod crustacean Palaemonetes varians. We used 2 populations of worms with different proportions of accumulated metals in different subcellular fractions as prey, and loaded the worms with radiolabelled metals either from sediment or from solution. Accumulated radiolabelled metals were fractionated into 5 components : metal-rich granules (MRG), cellular debris, organelles, metallothionein-like proteins (MTLP), and other (heat-sensitive) proteins (HSP). Assimilation efficiencies (AE) of the metals by P. varians were measured from the 4 categories of prey (i.e. 2 populations, radiolabelled from sediment or solution). There were significant differences for each metal between the AEs from the different prey categories, confirming that origin of prey and route of uptake of accumulated trace metal will cause intraspecific differences in subsequent metal assimilation. Correlations were sought between AEs and selected fractions or combinations of fractions of metals in the prey-MRG, Trophically Available Metal (TAM = MTLP + HSP + organelles) and total protein (MTLP + HSP). TAM explained 28% of the variance in AEs for Ag, but no consistent relationships emerged between AEs and TAM or total protein when the metals were considered separately. AEs did, however, show significant positive regressions with both TAM and total protein when the 3 metals were considered together, explaining only about 21 % of the variance in each case. A significant negative relationship was observed between MRG and AE for all metals combined. The predator (P. varians) can assimilate dietary metal from a range of the fractions binding metals in the prey (N. diversicolor), with different assimilation efficiencies summated across these

  13. Delonix regia and Casuarina equisetifolia as passive biomonitors and as bioaccumulators of atmospheric trace metals.

    PubMed

    Ukpebor, Emmanuel Ehiabhi; Ukpebor, Justina Ebehirieme; Aigbokhan, Emmanuel; Goji, Idris; Onojeghuo, Alex Okiemute; Okonkwo, Anthony Chinedum

    2010-01-01

    The suitability of two common and ubiquitously distributed and exotic ornamental plant species in Nigeria-Delonix regia and Casuarina equisetifolia as biomonitors and as effective bioaccumulators of atmospheric trace metals (Cd, Pb, Zn and Cu) has been evaluated. Bark and leaf samples from these plant species were collected in June and July 2006 at five locations in Benin City. Four of the sampling sites were in areas of high traffic density and commercial activities, the fifth site is a remote site, selected to act as a control and also to provide background information for the metals. The plant samples were collected and processed using standard procedures and trace metals were determined using atomic absorption spectrometer. The bark of the plants was able to bioaccumulate the trace metals, especially Pb which originates from anthropogenic contributions in the city. The Pb range of 20.00-70.00 microg/g measured for the bark samples of D. regia, exceeded the normal plant Pb concentration of 0.2-20.0 microg/g and most Pb data available in literature. The bark of the plants was observed to accumulate more metals compared to the leave, while D. regia was found to be slightly better than C. equisetifolia in trace metal uptake efficiency. Spatial variations in the distributions of Pb and Zn were significant (p < 0.05), and the continuous use of leaded fuel in Nigeria was identified as the predominant source of Pb in the atmosphere. PMID:21174998

  14. Trace Metals Affect Early Maternal Transfer of Immune Components in the Feral Pigeon.

    PubMed

    Chatelain, M; Gasparini, J; Haussy, C; Frantz, A

    2016-01-01

    Maternal early transfers of immune components influence eggs' hatching probability and nestlings' survival. They depend on females' own immunity and, because they are costly, on their physiological state. Therefore, trace metals, whether toxic and immunosuppressive (e.g., lead, cadmium, etc.) or necessary and immunostimulant (e.g., zinc, copper, iron, etc.), are likely to affect the amount of immune components transferred into the eggs. It may also vary with plumage eumelanin level, which is known to be linked to immunity, to transfer of antibodies, and to metal detoxification. In feral pigeons (Columba livia) injected with an antigen and experimentally exposed to lead and/or zinc (two highly abundant trace metals in urban areas), we measured specific antibody transfer and concentrations of two antimicrobial proteins (lysozyme and ovotransferrin) in eggs. As expected, lead had negative effects on specific antibody transfer, while zinc positively affected lysozyme egg concentrations. Moreover, eggs from lead-exposed females exhibited higher ovotransferrin concentrations; because it binds metal ions, ovotransferrin may enable egg detoxification and embryo protection. Finally, eggs' lysozyme concentrations increased with plumage darkness of females not exposed to zinc, while the relation was opposite among zinc-exposed females, suggesting that benefits and costs of plumage melanism depend on trace metal environmental levels. Overall, our study underlines the potential ecotoxicological effects of trace metals on maternal transfers of immune components and the role of plumage melanism in modulating these effects. PMID:27153130

  15. Trace metal fate in a rotary-kiln incinerator with an ionizing wet scrubber

    SciTech Connect

    Waterland, L.R.; Fournier, D.J.; Lee, J.W.; Carroll, G.J.

    1990-01-01

    A series of pilot-scale incineration tests was performed at EPA's Incineration Research Facility (IRF) in Jefferson, Arkansas, to evaluate the fate of trace metals fed to a rotary kiln incinerator equipped with an ionizing wet scrubber (IWS) for particulate and acid gas control. Test variables were kiln temperature, ranging from 816 to 927 C (1500 to 1700 F); afterburner temperature, ranging from 982 to 1204 C (1800 to 2200 F); and feed chlorine content, ranging from 0 to 8 percent. The test program evaluated the fate of five hazardous constituent trace metals (arsenic, barium, cadmium, chromium, and lead) and four nonhazardous constituent trace metals (bismuth, copper, magnesium, and strontium). The test results indicate that cadmium and bismuth were relatively volatile, with an average of less than 40 percent discharged with the kiln ash. Arsenic, barium, chromium, copper, lead, magnesium, and strontium were relatively nonvolatile, with an average of greater than 80 percent discharged with the kiln ash. Observed relative metal volatilities generally agreed with the volatilities predicted based on vapor pressure/temperature relationships, with the exception of arsenic which was much less volatile than predicted. The volatility of cadmium, bismuth, and lead increased as kiln temperature was increased; the discharge distributions of the remaining metals were not significantly affected by changes in kiln temperature. Apparent scrubber collection efficiencies for the metals averaged 22 to 71 percent, and were generally higher for the less volatile metals. The overall average metal collection efficiency was 43 percent.

  16. Trace metal distributions in the sediments of the Little Akaki River, Addis Ababa, Ethiopia.

    PubMed

    Akele, M L; Kelderman, P; Koning, C W; Irvine, K

    2016-07-01

    The levels and distribution of trace metals (Cr, Mn, Co, Ni, Cu, Zn, Cd and Pb) at eleven water and sediment stations on the Little Akaki River (LAR) in Addis Ababa, Ethiopia, were determined. The binding forms of the metals in various geochemical fractions of the sediments were also quantified. The molar ratio of the sum of the simultaneously extractable metals (∑SEM) and acid-volatile sulphide (AVS)-as a measure for predicting metal-induced toxicity-was estimated. LAR trace levels in water for Cu, Zn, and, particularly Mn were, in most instances, higher than the recommended guidelines for healthy aquatic ecosystems. Total trace metal (TTM) contents in the LAR sediments at certain stations exceeded "threshold effect concentrations" and even "probable effect concentrations", especially in the cases of Zn, Cu, Ni, Pb, and at all stations for Mn. This became more apparent after applying "normalizations" to the relatively lower TTM adsorption capacities of coarse-grained, organic-poor sediments. Sequential extraction of the sediments showed that trace metals generally have a higher affinity for Fe-Mn oxide and organic matter/sulphidic fractions, followed by the residual fraction. Mn was relatively strongly bound to the exchangeable, carbonate bound fractions, whereas a large proportion of Cr was found in the residual fraction. The Σ[SEM]/[AVS] ratio pointed to potential metal-induced toxicity of sediments collected from seven out of the eleven stations. The results indicate that trace metal pollution pose risks to the health of ecosystems, and to human communities that use the river for a range of different purposes. PMID:27260529

  17. BASELINE LEVELS OF TRACE METALS IN BLOOD OF CAPTIVE ASIAN ELEPHANTS (ELEPHAS MAXIMUS)

    PubMed Central

    Wiedner, Ellen B.; Takeuchi, Noel Y.; Isaza, Ramiro; Barber, David

    2013-01-01

    Whole blood from 33 healthy captive Asian elephants (Elephas maximus) was analyzed for 12 trace elements: aluminum, chromium, manganese, cobalt, nickel, copper, zinc, arsenic, selenium, cadmium, mercury, and lead for the purpose of estimating preliminary baseline population parameters for these minerals. Metals were quantified by inductively coupled plasma mass spectroscopy. Baseline ranges for all animals and for all trace elements were comparable to normal concentrations reported in other species. This is the first report of normal trace element levels in the blood of captive elephants. PMID:22946424

  18. Trace enrichment of metal ions in aquatic environments by Saccharomyces cerevisiae.

    PubMed

    Mapolelo, M; Torto, N

    2004-09-01

    Sorption properties of baker's yeast cells, characterised as Saccharomyces cerevisiae were evaluated for trace enrichment of metal ions: Cd(2+), Cr(3+), Cr(6+), Cu(2+), Pb(2+) and Zn(2+) from aqueous environments. Metal concentration was determined by flame atomic absorption spectrometry (FAAS). Parameters affecting metal uptake such as solution pH, incubation time, amount of yeast biomass and effect of glucose concentration (energy source) were optimised. Further studies were carried out to evaluate the effects on metal uptake after treating yeast with glucose as well as with an organic solvent. The results showed that trace enrichment of the metals under study with yeast, depends upon the amount of yeast biomass, pH and incubation time. Treatment of yeast cells with 10-20mM glucose concentration enhanced metal uptake with exception to Cr(6+), whose metal enrichment capacity decreased at glucose concentration of 60mM. Of the investigated organic solvents THF and DMSO showed the highest and lowest capacity, respectively, to enhance metal uptake by yeast cells. Trace enrichment of metal ions from stream water, dam water, treated wastewater from a sewage plant and wastewater from an electroplating plant achieved enrichment factors (EF) varying from 1 to 98, without pre-treatment of the sample. pH adjustment further enhanced the EF for all samples. The results from these studies demonstrate that yeast is a viable trace metal enrichment media that can be used freely suspended in solution to achieve very high EF in aquatic environments. PMID:18969566

  19. Health-risk assessment of incinerator stack emissions: Trace metals

    SciTech Connect

    Lee, Jinhong.

    1990-01-01

    The research presented in this dissertation centers on the development of a method for health risk assessment of incinerator stack emissions within the context of multiple exposure pathways and on its application to a problem of contemporary interest. The emphasis is on toxic metal emissions from municipal solid waste (MSW) incinerators. A comparison of the amount of metal emissions shows that toxic metal emissions from MSW incinerators are generally of the same order of magnitude as those from hazardous waste incinerators. A hazard index for stack emitted metals based on toxicity and quantity are developed in this dissertation to screen metals which are important from a risk view-point. From this hazard index, lead and mercury are added to the known carcinogenic metals, i.e., arsenic, beryllium, cadmium, chromium, and nickel as candidates for the assessment. The method presented in this dissertation consists of hazard identification and hazard quantification. If a substance is identified as a potential human carcinogen, the carcinogenicity may be related to the chemical form of a substance and the route of exposure. Regarding the carcinogenic potency of a pollutant, the chemical form of a substance and the route of exposure is investigated. This type of information with regard to carcinogenic uncertainty is incorporated into hazard quantification. The appropriate carcinogenic group of a pollutant is also identified. In order to quantify the human health risks for the 7 metals, the following are determined in this dissertation: emission factors; mass particle-size distributions; air dispersion models; exposure assessment models; population data; and unit risks or cancer potency factors.

  20. Trace metals partitioning among different sedimentary mineral phases and the deposit-feeding polychaete Armandia brevis.

    PubMed

    Díaz-de-Alba, Margarita; Huerta-Diaz, Miguel Angel; Delgadillo-Hinojosa, Francisco; Hare, Landis; Galindo-Riaño, M Dolores; Siqueiros-Valencia, Arturo

    2016-02-01

    Trace metals (Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn) were determined in two operationally defined fractions (HCl and pyrite) in sediments from Ensenada and El Sauzal harbors (Mexico). The HCl fraction had significantly higher metal concentrations relative to the pyrite fraction in both harbors, underlining the weak tendency of most trace metals to associate with pyrite. Exceptionally, Cu was highly pyritized, with degrees of trace metal pyritization (DTMP) >80% in both harbors. Dissolved Fe flux measurements combined with solid phase Fe sulfide data indicated that 98 mt of Fe are precipitated as iron sulfides every year in Ensenada Harbor. These Fe sulfides (and associated trace metals) will remain preserved in the sediments, unless they are perturbed by dredging or sediment resuspension. Calculations indicate that dredging activities could export to the open ocean 0.20±0.13 to (0.30±0.56)×10(3) mt of Cd and Cu, respectively, creating a potential threat to marine benthic organisms. Degrees of pyritization (DOP) values in Ensenada and El Sauzal harbors were relatively low (<25%) while degrees of sulfidization (DOS) were high (~50%) because of the contribution of acid volatile sulfide. DOP values correlated with DTMP values (p≤0.001), indicating that metals are gradually incorporated into pyrite as this mineral is formed. Significant correlations were also found between DTMP values and -log(Ksp(MeS)/Ksp(pyr)) for both harbors, indicating that incorporation of trace metals into the pyrite phase is a function of the solubility product of the corresponding metal sulfide. The order in which elements were pyritized in both harbors was Zn≈Mntrace metal concentrations and metal concentrations measured in Armandia brevis (a deposit-feeding Opheliid polychaete), suggesting that these labile sedimentary metals are preferentially accumulated by the polychaete, making it a

  1. Trace metals in gills of fish from the Arabian Gulf

    SciTech Connect

    Al-Yakoob, S.; Bahloul, M. ); Bou-Olayan, A.H.

    1994-11-01

    Complexation of metals by coordinate linkages with appropriate organic molecules in biological tissues is an important process involved in metal accumulation by aquatic organisms. Fish respiratory systems differ from all other systems because damage to gills has immediate impacts on the rest of the fish's body. Veer et al. observed significant correlation between gill-metal concentration and whole-body weight. More nickel is accumulated in gill tissue of the catfish (Clarias batrachus) than in the liver or intestine. More cadmium is accumulated in gill tissue of the fish Heteropneustes fossilis (Bloch) and Channa punctatus (Bloch) than in the liver or kidney. When exposed to lethal and sublethal concentrations of copper, gills of the freshwater fish Labeo rohita (Hamilton) showed the highest degree of copper accumulation. Petroleum and petrochemical industry wastes contribute significantly to metal enrichment of the Arabian Gulf marine environment. Because accumulation of metal ions is significant in gills, levels of Cd, Cr, Cu, Ni and Pb were investigated in gills of fish from potentially impacted areas along the western side of the Arabian Gulf after the 1991 oil-spill. 15 refs., 3 figs., 1 tab.

  2. Flexible digestion strategies and trace metal assimilation in marine bivalves

    USGS Publications Warehouse

    Decho, Alan W.; Luoma, Samuel N.

    1996-01-01

    Pulse-chase experiments show that two marine bivalves take optimal advantage of different types of particulate food by varying food retention time in a flexible two-phase digestive system. For example, carbon is efficiently assimilated from bacteria by subjecting nearly all the ingested bacteria to prolonged digestion. Prolonging digestion also enhances assimilation of metals, many of which are toxic in minute quantities if they are biologically available. Detritus-feeding aquatic organisms have always lived in environments naturally rich in particle-reactive metals. We suggest that avoiding excess assimilation of metals could be a factor in the evolution of digestion strategies. We tested that suggestion by studying digestion of particles containing different Cr concentrations. We show that bivalves are capable of modifying the digestive processing of food to reduce exposure to high, biologically available, Cr concentrations. The evolution of a mechanism in some species to avoid high concentrations of metals in food could influence how effects of modern metal pollution are manifested in marine ecosystems.

  3. Trace metals in estuarine sediments from the southwestern Spanish coast.

    PubMed

    Ruiz, F

    2001-06-01

    The impact of river-transported metal pollution and industrial wastes on the metal distribution (Cr, Cu, Zn, Pb) in estuarine sediments was studied in the southwestern Spanish estuaries. Intertidal and subtidal surface sediments of the Tinto-Odiel Estuary are very highly polluted by heavy metals, with geoaccumulation indices up to 4 in the three sedimentary environments studied (channel, channel border and salt marsh). The single exception is the Punta Umbria channel, very protected from the point sources by salt marsh deposits and hydraulic processes. In the remaining two estuaries, pollution (Pb, Cu) was only significant near the harbour situated in the Piedras river mouth, whereas very low values were found in the Guadiana Estuary. In these last rivers, the enrichment factor increases from the channel to the salt marsh sediments. PMID:11468926

  4. Lead Isotopic Composition and Trace Metals in Aerosols for Source Apportionment

    NASA Astrophysics Data System (ADS)

    Chien, C. T.; Paytan, A.

    2014-12-01

    Transported thousands of miles away from their source, aerosols can be dispersed and deposition throughout the Earth's surface. Aerosols from natural and industrial sources have different characteristics and health impacts thus it is important to identify their sources. The lead isotopic composition and trace metals in aerosol samples collected in different regions and periods around the world can help us better understand spatial and seasonal variation of aerosol sources. Aerosol samples collected in California, Bermuda, China and the Red Sea have been analyzed. The trace metal and Pb isotopes in these samples provide information regarding the various sources of aerosols to these sites.

  5. Trace metal content in aspirin and women's cosmetics via proton induced x-ray emission (PIXE)

    SciTech Connect

    Hichwa, B.P.; Pun, D.D.; Wang, D.

    1981-04-01

    A multielemental analysis to determine the trace metal content of generic and name-brand aspirins and name-brand lipsticks was done via proton induced x-ray (PIXE) measurements. The Hope College PIXE system is described as well as the target preparation methods. The trace metal content of twelve brands of aspirin and aspirin substitutes and fourteen brands of lipstick are reported. Detection limits for most elements are in the range of 100 parts per billion (ppb) to 10 parts per million (ppm).

  6. XFM of ``Trace Metals'' in Cultured Cells: Framing the Picture

    NASA Astrophysics Data System (ADS)

    Wolford, J.; Chishti, Y.; Ward, J.; Vogt, S.; Finney, L.

    2011-09-01

    Encouraged by our recent x-ray fluorescence microprobe analysis revealing subcellular metal relocation in two special cell types, we are working to identify the role of zinc and copper in these cells. In verifying that metal ion dynamics are not artifactual, particularly where some samples have been chemically fixed, a comparison of our past results with samples studied with cryofixation and immunofluorescence add validation to our previous findings. Our work demonstrating cryofixation in human microvascular endothelial cells and metallothionein immunofluorescence in stem cells is presented.

  7. Aquatic insects as biomonitors of trace metal contamination

    SciTech Connect

    Popp, C.J.; Lynch, T.R. ); Jacobi, G.Z. )

    1989-01-01

    The concentrations of 13 heavy metals in water, stream sediments, and a variety of aquatic insects in the Red River above and below the Molycorp mine and mill is reported. The mine-mill complex is located between the towns of Red River and Questa and is connected by a pipeline to a tailings disposal pond located about 8 km downstream of Questa. The pipeline is adjacent the Red River. Numerous breaks have occurred in the pipeline in the past resulting in processed milled tailings being discharged directly into the river. Atomic absorption was used for metal analysis. Experimental results are presented.

  8. Trace Metals and Metalloids in Forest Soils and Exotic Earthworms in Northern New England, USA

    PubMed Central

    Richardson, J.B.; Görres, J.H.; Jackson, B.P.; Friedland, A.J.

    2015-01-01

    Trace metals and metalloids (TMM) in forest soils and invasive earthworms were studied at 9 uncontaminated sites in northern New England, USA. Essential (Cu, Mo, Ni, Zn, Se) and toxic (As, Cd, Pb, Hg and U) TMM concentrations (mg kg-1) and pools (mg m-2) were quantified for organic horizons (forest floor), mineral soils and earthworm tissues. Essential TMM tissue concentrations were greatest for mineral soil-feeding earthworm Octolasion cyaneum. Toxic TMM tissue concentrations were highest for organic horizon-feeding earthworms Dendobaena octaedra, Aporrectodea rosea and Amynthas agrestis. Most earthworm species had attained tissue concentrations of Pb, Hg and Se potentially hazardous to predators. Bioaccumulation factors were Cd > Se > Hg > Zn > Pb > U > 1.0 > Cu > As > Mo > Ni. Only Cd, Se Hg and Zn were considered strongly bioaccumulated by earthworms because their average bioaccumulation factors were significantly greater than 1.0. Differences in bioaccumulation did not appear to be caused by soil concentrations as earthworm TMM tissue concentrations were poorly correlated with TMM soil concentrations. Instead, TMM bioaccumulation appears to be species and site dependent. The invasive Amynthas agrestis had the greatest tissue TMM pools, due to its large body mass and high abundance at our stands. We observed that TMM tissue pools in earthworms were comparable or exceeded organic horizon TMM pools; earthworm tissue pools of Cd were up 12 times greater than in the organic horizon. Thus, exotic earthworms may represent an unaccounted portion and flux of TMM in forests of the northeastern US. Our results highlight the importance of earthworms in TMM cycling in northern forests and warrant more research into their impact across the region. PMID:25883392

  9. Trace metal storage in recent floodplain sediments along the Dill River, central Germany

    NASA Astrophysics Data System (ADS)

    Martin, Charles W.

    2015-04-01

    Trace metals are stored in near-channel floodplain sediments along many rivers in industrial and mined watersheds of western European countries such as Germany. In this paper, I document the distribution of Cu, Pb, and Zn in 13 cores collected from near-channel floodplain sediments along a 25-km reach of the Dill River in central Germany. Mean concentrations of the three trace metals exceed background concentrations, an indication of anthropogenic enrichment along the study reach; many individual samples have concentrations several times the background levels and exceed standards for trace metals contained in the German Federal Soil Protection Act. Metal concentrations generally peak at depths of 0.2 to 0.7 m below the floodplain surface and are assumed to represent the period of maximum metal releases to the environment through upstream industrial activity, ore mining, or both. In eight of the cores, radiocarbon ages obtained below the depth of peak metal concentrations provide maximum dates for sediment accumulation of between 90 and 1700 years ago, with most ages clustering in the period of 90 to 300 years ago. The ages and depth to peak metal concentrations indicate 0.6 to 1.0 m of floodplain sedimentation over the last 150 to 300 years (0.3-0.4 cm y- 1), which exceed sedimentation amounts and rates found in surrounding watersheds. Surface sediments contain lower metal concentrations, suggesting deposition recently of cleaner sediments. Trace metals stored along the Dill River serve as a reminder that stores of contaminants exist in geomorphically sensitive locations of the fluvial system. These legacy sediments bear the chemical imprint of industrial or mining activities that no longer occur in the watershed.

  10. Seasonal variation and sources of dissolved trace metals in Maó Harbour, Minorca Island.

    PubMed

    Martínez-Soto, Marly C; Tovar-Sánchez, Antonio; Sánchez-Quiles, David; Rodellas, Valentí; Garcia-Orellana, Jordi; Basterretxea, Gotzon

    2016-09-15

    The environmental conditions of semi-enclosed coastal water-bodies are directly related to the catchment, human activities, and oceanographic setting in which they are located. As a result of low tidal forcing, and generally weak currents, waters in Mediterranean harbours are poorly renewed, leading to quality deterioration. Here, we characterise the seasonal variation of trace metals (i.e. Co, Cd, Cu, Fe, Mo, Ni, Pb, and Zn) in surface waters, and trace metal content in sediments from Maó Harbour, a semi-enclosed coastal ecosystem in the NW Mediterranean Sea. Our results show that most of the dissolved trace metals in the waters of Maó Harbour exhibit a marked inner-outer concentration gradient, suggesting a permanent input into the inner part of the harbour. In general, metal concentrations in the waters of Maó Harbour are higher than those in offshore waters. Concentration of Cu (21±8nM), Fe (9.2±3.2nM) and Pb (1.3±0.4nM) are particularly high when compared with other coastal areas of the Mediterranean Sea. The concentration of some metals such as Cu and Zn increases during summertime, when the human population and boat traffic increase during the tourism season, and when resuspension from the metal enriched sediments is higher. The evaluation of the metal sources in the harbour reveals that, compared with other putative sources such as runoff, aerosol deposition and fresh groundwater discharges, contaminated sediments are the main source of the metals found in the water column, most likely through vessel-driven resuspension events. This study contributes to the understanding of the processes that control the occurrence and distribution of trace metals in Maó Harbour, thus aiding in the effective management of the harbour, and enhancing the overall quality of the seawater ecosystem. PMID:27163484

  11. Estuaries as Filters: The Role of Tidal Marshes in Trace Metal Removal

    PubMed Central

    Teuchies, Johannes; Vandenbruwaene, Wouter; Carpentier, Roos; Bervoets, Lieven; Temmerman, Stijn; Wang, Chen; Maris, Tom; Cox, Tom J. S.; Van Braeckel, Alexander; Meire, Patrick

    2013-01-01

    Flux calculations demonstrate that many estuaries are natural filters for trace metals. Yet, the underlying processes are poorly investigated. In the present study, it was hypothesized that intertidal marshes contribute significantly to the contaminant filter function of estuaries. Trace metal concentrations and sediment characteristics were measured along a transect from the subtidal, over an intertidal flat and marsh to a restored marsh with controlled reduced tide. Metal concentrations in the intertidal and restored marsh were found to be a factor two to five higher than values in the subtidal and intertidal flat sediments. High metal concentrations and high accretion rates indicate a high metal accumulation capacity of the intertidal marshes. Overbank sedimentation in the tidal marshes of the entire estuary was calculated to remove 25% to 50% of the riverine metal influx, even though marshes comprise less than 8% of the total surface of the estuary. In addition, the large-scale implementation of planned tidal marsh restoration projects was estimated to almost double the trace metal storage capacity of the present natural tidal marshes in the estuary. PMID:23950927

  12. Fluxes and retention of trace metals in the Humber Estuary

    NASA Astrophysics Data System (ADS)

    Millward, G. E.; Glegg, G. A.

    1997-01-01

    The Humber Estuary is a physically dynamic system into which industrial wastes contaminated with heavy metals have been discharged for many years. The total fluxes of Cd, Cu, Fe, Ni, Pb and Zn from the Humber Estuary to the North Sea have been estimated for December 1988, May 1990 and August 1990. These fluxes have been compared to inputs into the estuary from rivers, sewage and industry as reported by the Paris Commission. A discrepancy exists between the estuarine inputs and the fluxes to the North Sea, which suggests that the estuary is acting as a trap for fine, metal-contaminated sediments. An alternative approach to flux assessment also indicates that metal retention by sediments is a major feature of the Humber Estuary. The results are discussed in the context of the recovery of the estuary from metal contamination and the consequences for the coastal zone. This critical review allows assessment of effectiveness of current management strategies and new directions for the future to be proposed.

  13. Reconstructing Early Industrial Contributions to Legacy Trace Metal Contamination in Southwestern Pennsylvania

    NASA Astrophysics Data System (ADS)

    Rossi, R.; Bain, D.; Hillman, A. L.; Pompeani, D. P.; Abbott, M. B.

    2015-12-01

    The remobilization of legacy contamination stored in floodplain sediments remains a threat to ecosystem and human health, particularly with potential changes in global precipitation patterns and flooding regimes. Vehicular and industrial emissions are often the dominant, recognized source of anthropogenic trace metal loadings to ecosystems today. However, loadings from early industrial activities are poorly characterized and potential sources of trace metal inputs. While potential trace metal contamination from these activities is recognized (e.g., the historical use of lead arsenate as a pesticide), the magnitude and distribution of legacy contamination is often unknown. This presentation reconstructs a lake sediment record of trace metal inputs from an oxbow lake in Southwestern Pennsylvania. Sediment cores were analyzed for major and trace metal chemistry, carbon to nitrogen ratios, bulk density, and magnetic susceptibility. Sediment trace metal chemistry in this approximately 250 year record (180 cm) record changes in land use and industry both in the 19th century and the 20th century. Of particular interest is early 19th century loadings of arsenic and calcium to the lake, likely attributable to pesticides and lime used in tanning processes near the lake. After this period of tanning dominated inputs, sediment barium concentrations rise, likely reflecting the onset of coal mining operations and resulting discharge of acid mine drainage to surface waters. In the 20th century portion of our record (70 -20 cm), patterns in sediment zinc, cadmium, and lead concentrations are dominated by the opening and closing of the nearby Donora Zinc Works and the American Steel & Wire Works, infamous facilities in the history of air quality regulation. The most recent sediment chemistry records periods include the enactment of air pollution legislation (~ 35 cm), and the phase out of tetraethyl leaded gasoline (~30 cm). Our study documents the impact of early industry in the

  14. Quantitative Trait Loci and Inter-Organ Partitioning for Essential Metal and Toxic Analogue Accumulation in Barley

    PubMed Central

    Reuscher, Stefan; Kolter, Andreas; Hoffmann, Astrid; Pillen, Klaus

    2016-01-01

    The concentrations of both essential nutrients and chemically similar toxic analogues accumulated in cereal grains have a major impact on the nutritional quality and safety of crops. Naturally occurring genetic diversity can be exploited for the breeding of improved varieties through introgression lines (ILs). In this study, multi-element analysis was conducted on vegetative leaves, senesced flag leaves and mature grains of a set of 54 ILs of the wild ancestral Hordeum vulgare ssp. spontaneum in the cultivated variety Hordeum vulgare ssp. vulgare cv. Scarlett. Plants were cultivated on an anthropogenically heavy metal-contaminated soil collected in an agricultural field, thus allowing simultaneous localization of quantitative trait loci (QTL) for the accumulation of both essential nutrients and toxic trace elements in barley as a model cereal crop. For accumulation of the micronutrients Fe and Zn and the interfering toxin Cd, we identified 25, 16 and 5 QTL, respectively. By examining the gene content of the introgressions, we associated QTL with candidate genes based on homology to known metal homeostasis genes of Arabidopsis and rice. Global comparative analyses suggested the preferential remobilization of Cu and Fe, over Cd, from the flag leaf to developing grains. Our data identifies grain micronutrient filling as a regulated and nutrient-specific process, which operates differently from vegetative micronutrient homoeostasis. In summary, this study provides novel QTL for micronutrient accumulation in the presence of toxic analogues and supports a higher degree of metal specificity of trace element partitioning during grain filling in barley than previously reported for other cereals. PMID:27078500

  15. Trace metal capture by various sorbents during fluidized bed coal combustion

    SciTech Connect

    Ho, T.C.; Ghebremeskel, A.; Wang, K.S.; Hopper, J.R.

    1997-07-01

    This study investigated the potential of employing suitable sorbents to capture toxic trace metallic substances during fluidized bed coal combustion. Metal capture experiments were carried out in a 25.4 mm (1 inch) quartz fluidized bed combustor enclosed in an electric furnace. The metals involved were cadmium, lead, chromium, arsenic and selenium, and the sorbents tested included bauxite, zeolite and lime. In addition to the experimental investigations, potential metal-sorbent reactions were also identified through chemical equilibrium calculations based on the minimization of system free energy. The observed experimental results indicated that metal capture by sorbents can be as high as 88% depending on the metal species and sorbent involved. Results from thermodynamic equilibrium simulations suggested the formation of metal-sorbent compounds such as Pb{sub 2}SiO{sub 4}(s), CdAl{sub 2}O{sub 4}(s) and CdSiO{sub 3}(s) under the combustion conditions.

  16. From waste water treatment to land management: Conversion of aquatic biomass to biochar for soil amelioration and the fortification of crops with essential trace elements.

    PubMed

    Roberts, David A; Paul, Nicholas A; Cole, Andrew J; de Nys, Rocky

    2015-07-01

    Macroalgae can be grown in industrial waste water to sequester metals and the resulting biomass used for biotechnological applications. We have previously cultivated the freshwater macroalga Oedogonium at a coal-fired power station to treat a metal-contaminated effluent from that facility. We then produced biochar from this biomass and determined the suitability of both the biomass and the biochar for soil amelioration. The dried biomass of Oedogonium cultivated in the waste water contained several elements for which there are terrestrial biosolids criteria (As, Cd, Cr, Cu, Pb, Ni, Se and Zn) and leached significant amounts of these elements into solution. Here, we demonstrate that these biomass leachates impair the germination and growth of radishes as a model crop. However, the biochar produced from this same biomass leaches negligible amounts of metal into solution and the leachates support high germination and growth of radishes. Biochar produced at 750 °C leaches the least metal and has the highest recalcitrant C content. When this biochar is added to a low-quality soil it improves the retention of nutrients (N, P, Ca, Mg, K and Mo) from fertilizer in the soil and the growth of radishes by 35-40%. Radishes grown in the soils amended with the biochar have equal or lower metal contents than radishes grown in soil without biochar, but much higher concentrations of essential trace elements (Mo) and macro nutrients (P, K, Ca and Mg). The cultivation of macroalgae is an effective waste water bioremediation technology that also produces biomass that can be used as a feedstock for conversion to biochar for soil amelioration. PMID:25881153

  17. Rapid and gradual modes of aerosol trace metal dissolution in seawater

    PubMed Central

    Mackey, Katherine R. M.; Chien, Chia-Te; Post, Anton F.; Saito, Mak A.; Paytan, Adina

    2015-01-01

    Atmospheric deposition is a major source of trace metals in marine surface waters and supplies vital micronutrients to phytoplankton, yet measured aerosol trace metal solubility values are operationally defined, and there are relatively few multi-element studies on aerosol-metal solubility in seawater. Here we measure the solubility of aluminum (Al), cadmium (Cd), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) from natural aerosol samples in seawater over a 7 days period to (1) evaluate the role of extraction time in trace metal dissolution behavior and (2) explore how the individual dissolution patterns could influence biota. Dissolution behavior occurs over a continuum ranging from rapid dissolution, in which the majority of soluble metal dissolved immediately upon seawater exposure (Cd and Co in our samples), to gradual dissolution, where metals dissolved slowly over time (Zn, Mn, Cu, and Al in our samples). Additionally, dissolution affected by interactions with particles was observed in which a decline in soluble metal concentration over time occurred (Fe and Pb in our samples). Natural variability in aerosol chemistry between samples can cause metals to display different dissolution kinetics in different samples, and this was particularly evident for Ni, for which samples showed a broad range of dissolution rates. The elemental molar ratio of metals in the bulk aerosols was 23,189Fe: 22,651Al: 445Mn: 348Zn: 71Cu: 48Ni: 23Pb: 9Co: 1Cd, whereas the seawater soluble molar ratio after 7 days of leaching was 11Fe: 620Al: 205Mn: 240Zn: 20Cu: 14Ni: 9Pb: 2Co: 1Cd. The different kinetics and ratios of aerosol metal dissolution have implications for phytoplankton nutrition, and highlight the need for unified extraction protocols that simulate aerosol metal dissolution in the surface ocean. PMID:25653645

  18. Adsorption of trace metals to plastic resin pellets in the marine environment.

    PubMed

    Holmes, Luke A; Turner, Andrew; Thompson, Richard C

    2012-01-01

    Plastic production pellets collected from beaches of south west England contain variable concentrations of trace metals (Cr, Co, Ni, Cu, Zn, Cd and Pb) that, in some cases, exceed concentrations reported for local estuarine sediments. The rates and mechanisms by which metals associate with virgin and beached polyethylene pellets were studied by adding a cocktail of 5 μg L(-1) of trace metals to 10 g L(-1) pellet suspensions in filtered seawater. Kinetic profiles were modelled using a pseudo-first-order equation and yielded response times of less than about 100 h and equilibrium partition coefficients of up to about 225 ml g(-1) that were consistently higher for beached pellets than virgin pellets. Adsorption isotherms conformed to both the Langmuir and Freundlich equations and adsorption capacities were greater for beached pellets than for virgin pellets. Results suggest that plastics may represent an important vehicle for the transport of metals in the marine environment. PMID:22035924

  19. Authigenesis of trace metals in energetic tropical shelf environments

    USGS Publications Warehouse

    Breckel, E.J.; Emerson, S.; Balistrieri, L.S.

    2005-01-01

    We evaluated authigenic changes of Fe, Mn, V, U, Mo, Cd and Re in suboxic, periodically remobilized, tropical shelf sediments from the Amazon continental shelf and the Gulf of Papua. The Cd/Al, Mo/Al, and U/Al ratios in Amazon shelf sediments were 82%, 37%, and 16% less than those in Amazon River suspended sediments, respectively. Very large depletions of U previously reported in this environment were not observed. The Cd/Al ratios in Gulf of Papua sediments were 76% lower than measurements made on several Papua New Guinea rivers, whereas U/Al ratios in the shelf sediments were enriched by approximately 20%. Other metal/Al ratios in the Papua New Guinea river suspended sediments and continental shelf sediments were not distinguishably different. Comparison of metal/Al ratios to grain size distributions in Gulf of Papua samples indicates that our observations cannot be attributed to differences in grain size between the river suspended sediments and continental shelf sediments. These two shelves constitute a source of dissolved Cd to the world ocean equal to 29-100% of the dissolved Cd input from rivers, but only 3% of the dissolved Mo input and 4% of the dissolved U input. Release of Cd, Mo, and U in tropical shelf sediments is likely a result of intense Fe and Mn oxide reduction in pore waters and resuspension of the sediments. Since we do not observe depletions of particulate Fe and Mn in the shelf sediments most of these dissolved metals must reoxidize in the overlying waters and reprecipitate. As Cd exhibits the largest losses on these tropical shelves, we examined the ability of newly formed Fe and Mn oxides to adsorb dissolved Cd using a geochemical diffuse double-layer surface complexation model and found the oxide surfaces are relatively ineffective at readsorbing Cd in seawater due to surface-site competition by Mg and Ca. If the remobilization and reoxidation of Fe and Mn occurs frequently enough before sediment is buried significant amounts of Cd may be

  20. Water and acid soluble trace metals in atmospheric particles

    NASA Technical Reports Server (NTRS)

    Lindberg, S. E.; Harriss, R. C.

    1983-01-01

    Continental aerosols are collected above a deciduous forest in eastern Tennessee and subjected to selective extractions to determine the water-soluble and acid-leachable concentrations of Cd, Mn, Pb, and Zn. The combined contributions of these metals to the total aerosol mass is 0.5 percent, with approximately 70 percent of this attributable to Pb alone. A substantial fraction (approximately 50 percent or more) of the acid-leachable metals is soluble in distilled water. In general, this water-soluble fraction increases with decreasing particle size and with increasing frequency of atmospheric water vapor saturation during the sampling period. The pattern of relative solubilities (Zn being greater than Mn, which is approximately equal to Cd, which is greater than Pb) is found to be similar to the general order of the thermodynamic solubilities of the most probable salts of these elements in continental aerosols with mixed fossil fuel and soil sources.

  1. Assessment of essential and nonessential metals and different metal exposure biomarkers in the human placenta in a population from the south of Portugal.

    PubMed

    Serafim, A; Company, R; Lopes, B; Rosa, J; Cavaco, A; Castela, G; Castela, E; Olea, N; Bebianno, M J

    2012-01-01

    The general population is exposed to metals as trace amounts of metallic compounds are present in air, water, and food. Information on background exposures and biomarker concentrations of environmental chemicals in the general Portuguese population is limited. Therefore, the purpose of this study was to determine the levels of important nonessential metals with recognized toxicity cadmium (Cd) and lead (Pb) and essential metals copper (Cu), nickel (Ni), chromium (Cr), and zinc (Zn) in placentas of mothers living in south Portugal (Algarve). Due to the difficulty in establishing the effects of chemicals in a complex and variable environment, this study also aimed to examine the response of biomarkers, such as biochemical changes that occurs at subcellular levels in the presence of contaminants. The investigated biomarkers in placentas indicative of metal exposure or damage included the metallothioneins (MT), delta-aminolevulinic acid dehydratase (ALAD) (specific for Pb), and lipid peroxidation (LPO) as an index of oxidative stress damage. Moreover, HJ-BIPLOT was applied in order to identify and categorize mothers vulnerable to environmental contamination in this region. Metal concentrations in the placenta were not excessive but within the range found in most European studies. In general, the biomarkers MT and LPO were positively correlated with metal levels, while with ALAD the opposite occurred, indicating the selected battery of biomarkers were suitable to study the effects of metals on human placenta. Further, the application of multivariate analysis with HJ-BIPLOT showed that most significant factors contributing to maternal and fetal exposures via placenta were dietary and smoking habits. PMID:22788373

  2. Trace metal preconcentration using a thioglycolate chelating resin

    SciTech Connect

    Howard, A.G.; Danilona-Mirzaians, R.

    1989-01-01

    A styrene-divinyl benzene copolymer resin (Amberlite XAD-4), modified with thioglycolate complexing groups, has been employed for the preconcentration of cadmium, zinc, lead and nickel from natural waters. The resin exhibits its strongest affinity for cadmium and lead but can be used to quantitatively remove all four metals from non-saline waters. With seawater samples, the resin is best only employed for the enrichment of cadmium and lead as the recovery of nickel and zinc from this medium is poor.

  3. Atmospherically deposited trace metals from bulk mineral concentrate port operations.

    PubMed

    Taylor, Mark Patrick

    2015-05-15

    Although metal exposures in the environment have declined over the last two decades, certain activities and locations still present a risk of harm to human health. This study examines environmental dust metal and metalloid hazards (arsenic, cadmium, lead and nickel) associated with bulk mineral transport, loading and unloading port operations in public locations and children's playgrounds in the inner city of Townsville, northern Queensland. The mean increase in lead on post-play hand wipes (965 μg/m(2)/day) across all sites was more than 10-times the mean pre-play loadings (95 μg/m(2)/day). Maximum loading values after a 10-minute play period were 3012 μg/m(2), more than seven times the goal of 400 μg/m(2) used by the Government of Western Australia (2011). Maximum daily nickel post-play hand loadings (404 μg/m(2)) were more than 26 times above the German Federal Immission Control Act 2002 annual benchmark of 15 μg/m(2)/day. Repeat sampling over the 5-day study period showed that hands and surfaces were re-contaminated daily from the deposition of metal-rich atmospheric dusts. Lead isotopic composition analysis of dust wipes ((208)Pb/(207)Pb and (206)Pb/(207)Pb) showed that surface dust lead was similar to Mount Isa type ores, which are exported through the Port of Townsville. While dust metal contaminant loadings are lower than other mining and smelting towns in Australia, they exceeded national and international benchmarks for environmental quality. The lessons from this study are clear - even where operations are considered acceptable by managing authorities, targeted assessment and monitoring can be used to evaluate whether current management practices are truly best practice. Reassessment can identify opportunities for improvement and maximum environmental and human health protection. PMID:25706750

  4. Trace metal dynamics in floodplain soils of the river Elbe: a review.

    PubMed

    Schulz-Zunkel, Christiane; Krueger, Frank

    2009-01-01

    This paper reviews trace metal dynamics in floodplain soils using the Elbe floodplains in Germany as an example of extraordinary importance because of the pollution level of its sediments and soils. Trace metal dynamics are determined by processes of retention and release, which are influenced by a number of soil properties including pH value, redox potential, organic matter, type and amount of clay minerals, iron-, manganese- and aluminum-oxides. Today floodplains act as important sinks for contaminants but under changing hydraulic and geochemical conditions they may also act as sources for pollutants. In floodplains such changes may be extremes in flooding or dry periods that particularly lead to altered redox potentials and that in turn influence the pH value, the mineralization of organic matter as well as the charge of the pedogenic oxides. Such reactions may affect the bioavailability of trace metals in soils and it can be clearly seen that the bioavailability of metals is an important factor for estimating trace metal remobilization in floodplain soils. However as bioavailability is not a constant factor, there is still a lack of quantification of metal mobilization particularly on the basis of changing geochemical conditions. Moreover, mobile amounts of metals in the soil solution do not indicate to which extent remobilized metals will be transported to water bodies or plants and therefore potentially have toxicological effects. Consequently, floodplain areas still need to be taken into consideration when studying the role and behavior of sediments and soils for transporting pollutants within river systems, particularly concerning the Water Framework Directive. PMID:19465710

  5. High concentrations of trace metals in oysters from the Patuxent River, Maryland

    SciTech Connect

    Riedel, G.; Sanders, J.; Abbe, G.

    1995-12-31

    Oyster (Crassostrea virginica) populations from the Patuxent River have been analyzed for trace metals by a number of organizations over at least the past 19 years. During that period, high concentrations of Cu (200--500 {micro}g/g dry weight), Cd (3--7 {micro}g/g) and Ag (2--8 /{micro}g/g) have been found in oysters from the oyster bars furthest up river. In particular, Cd values in oysters from this region have had concentrations approaching or exceeding current FDA warning levels throughout the period. In previous studies it was suggested that a coal-burning power plant located in that region, Chalk Point Steam Electric Station, was responsible for the copper enrichment due to the corrosion of Cu/Ni alloy condenser tubes. However, a monthly survey of trace elements in the nearby oyster populations from 1986 to the present showed only a small decline in copper concentrations after the plant switched from Cu/Ni to Ti alloy condenser tubes in 1987. Other potential sources for trace metals in the region include municipal and industrial discharges, atmospheric deposition, and biocides (anti-fouling paint in particular). The very rapid rise in trace element concentrations in oysters with position up river, and the lack of such a response by another local bivalve, the hooked mussel (Ischadium recurvum), suggests that a physiological effect of low salinity stress on oysters may be in part responsible for the high concentrations of trace metals in oysters in this region.

  6. Airborne trace metals and organochlorine compounds in arctic Alaska and Siberia: How important?

    SciTech Connect

    Landers, D.H.; Allen-Gil, S.; Gubala, C.P.; Ford, J.

    1995-12-31

    Metal contaminants of anthropogenic origin identified in the arctic atmosphere and the presence of organochlorines in arctic marine mammal tissues has raised the question of the importance of long-range transport of contaminants to the Arctic. Research focused on arctic regions in Alaska and the Taimyr peninsula of north central Russia. Inland watersheds were examined for evidence of increases in trace metal flux during the past 150 years and the presence of organochlorine compounds. Fish and ground squirrels were examined for body burdens of organic contaminants and plasma biomarkers were examined to evaluate biological effects. Sediment data from several lakes suggest that over broad regions, trace metal fluxes have increased only slightly (< 10%), if at all, since the pre-industrial era. The highest metal concentrations in lake sediments are associated with known elevated geologic sources of metals within the respective watersheds. Organochlorines are present in remote inland arctic ecosystems and are most concentrated in the tissues (e.g. liver) of organisms representing higher trophic levels. Arctic Siberia and Alaska (Taimyr peninsula) are similar with regard to contaminant concentrations. However, lichen and moss data suggest that Pb from Eurasian sources does not reach arctic Alaska. The results indicate that long range, transpolar transport and deposition of trace metals is not a large scale current phenomena in the two study regions. The transport and deposition of organochlorine compounds, however, is occurring but at relatively low levels.

  7. Evaluating three trace metal contaminated sites: a field and laboratory investigation.

    PubMed

    Murray, P; Ge, Y; Hendershot, W H

    2000-01-01

    Selecting guidelines to evaluate elevated metals in urban brownfields is hindered by the lack of information for these sites on ecosystem structure and function. A study was performed to compare three trace metal-contaminated sites in the metropolitan Montreal area. The goal was to obtain an idea of the organisms that may be present on urban brownfields and to measure if elevated metals alter the presence and activity of the indigenous biota. Field and laboratory studies were conducted using simple methodologies to determine the extent to which microbial activity affected by trace metal content, to assess diversity of plant and soil invertebrate communities and to measure phytoaccumulation of trace metals. It was found that microbial activity, as measured by substrate-induced respiration (SIR) and nitrification, was not affected by the levels of soil Cd, Cu, Ni, Pb and Zn recorded on the sites. Seven of the 12 invertebrate groups collected were sampled on soils with similar Cd, Cu, Ni, Pb and Zn concentrations. Diversity of plant species increased as a function of the length of time the sites had been inactive. Levels of metals in plant tissue were influenced by soil characteristics and not by total soil Cd, Cu, Ni, Pb and Zn. PMID:15093016

  8. Trace metal levels in fruit juices and carbonated beverages in Nigeria.

    PubMed

    Williams, Akan B; Ayejuyo, Olusegun O; Ogunyale, Adekunle F

    2009-09-01

    Trace metal levels in selected fruit juices and carbonated beverages purchased in Lagos, Nigeria were determined using atomic absorption spectrophotometer (Unicam model 969) equipped with SOLAAR 32 windows software. Fruit juices analysed were grape, pineapple, apple, orange, lemon juices and their brand names were used. Some carbonated drinks were also evaluated for metal levels. Trace metals investigated were Cr, Cu, Pb, Mn, Ni, Zn, Sn, Fe, Cd and Co. Trace metal contents of fruit juices were found to be more than the metallic contents of carbonated beverages. Pb level in the fruit juices ranged from 0.08 to 0.57 mg/l but was not detected in the carbonated drinks. Concentrations of Pb in lemon juice and Mn in pineapple juice were relatively high. Cd and Co were not detected in the selected juices and beverages. Additionally, Pb, Cu, Cr and Fe were not detected in canned beverages but were present in bottled beverages. However, the metal levels of selected fruit juices and carbonated beverages were within permissible levels except for Mn in pineapple juice and Pb in lemon juice. PMID:18704729

  9. Trace metal geochemistry in mangrove sediments and their transfer to mangrove plants (New Caledonia).

    PubMed

    Marchand, C; Fernandez, J-M; Moreton, B

    2016-08-15

    Because of their physico-chemical inherent properties, mangrove sediments may act as a sink for pollutants coming from catchments. The main objective of this study was to assess the distribution of some trace metals in the tissues of various mangrove plants developing downstream highly weathered ferralsols, taking into account metals partitioning in the sediment. In New Caledonia, mangroves act as a buffer between open-cast mines and the world's largest lagoon. As a result of the erosion of lateritic soils, Ni and Fe concentrations in the sediment were substantially higher than the world average. Whatever the mangrove stand and despite low bioaccumulation and translocations factors, Fe and Ni were also the most abundant metals in the different plant tissues. This low bioaccumulation may be explained by: i) the low availability of metals, which were mainly present in the form of oxides or sulfur minerals, and ii) the root systems acting as barriers towards the transfer of metals to the plant. Conversely, Cu and Zn metals had a greater mobility in the plant, and were characterized by high bioconcentration and translocation factors compared to the other metals. Cu and Zn were also more mobile in the sediment as a result of their association with organic matter. Whatever the metal, a strong decrease of trace metal stock was observed from the landside to the seaside of the mangrove, probably as a result of the increased reactivity of the sediment due to OM enrichment. This reactivity lead to higher dissolution of bearing phases, and thus to the export of dissolved trace metals trough the tidal action. Cu and Zn were the less concerned by the phenomenon probably as a result of higher plant uptake and their restitution to the sediment with litter fall in stands where tidal flushing is limited. PMID:27100002

  10. TRACE METAL FATE IN A ROTARY KILN INCINERATOR WITH AN IONIZING WET SCRUBBER

    EPA Science Inventory

    A series of pilot-scale incineration tests performed at EPA's Incineration Research Facility (IRF) in Jefferson, Arkansas, to evaluate the fate of trace metals fed to a rotary kiln incinerator equipped with an ionizing wet scrubber (IWS) for particulate and acid gas control. est ...

  11. Changes in trace metals in hemolymph of baculovirus infected noctuid larvae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We studied how biologically relevant trace metals (i.e., micronutrients) in the plasma of larvae of Heliothis virescens and Helicoverpa zea (Lepidoptera: Noctuidae) changed in response to per os baculovirus infection, larval development, and injection of heat-killed bacteria. Concentrations of plas...

  12. NOVEL MODEL DESCRIBING TRACE METAL CONCENTRATIONS IN THE EARTHWORM, EISENIA ANDREI: JOURNAL ARTICLE

    EPA Science Inventory

    NRMRL-CIN-1707 Sake, J.K., Impellitteri**, C.A., Peijnenburg, W., and Allen, H.E. Novel Model Describing Trace Metal Concentrations in the Earthworm, Eisenia andrei. Environmental Science & Technology (American Chemical Society) 35 (22):4522-4529 (2001). EPA/600/J-01/364. 12/12/2...

  13. Quantitative Ultrasound-Assisted Extraction for Trace-Metal Determination: An Experiment for Analytical Chemistry

    ERIC Educational Resources Information Center

    Lavilla, Isela; Costas, Marta; Pena-Pereira, Francisco; Gil, Sandra; Bendicho, Carlos

    2011-01-01

    Ultrasound-assisted extraction (UAE) is introduced to upper-level analytical chemistry students as a simple strategy focused on sample preparation for trace-metal determination in biological tissues. Nickel extraction in seafood samples and quantification by electrothermal atomic absorption spectrometry (ETAAS) are carried out by a team of four…

  14. TRACE METAL RETENTION WHEN FIRING HAZARDOUS WASTE IN A FLUIDIZED-BED INCINERATOR

    EPA Science Inventory

    The report describes a bench-scale fluidized-bed incinerator that will capture trace metals on the bed material when firing hazardous waste. The design is based on limited tests at an existing laboratory facility. Operating conditions, operating procedures, and equipment design a...

  15. Assessment of trace metal pollution in sediments and intertidal fauna at the coast of Cameroon.

    PubMed

    Ngeve, Magdalene N; Leermakers, Martine; Elskens, Marc; Kochzius, Marc

    2015-06-01

    Coastal systems act as a boundary between land and sea. Therefore, assessing pollutant concentrations at the coast will provide information on the impact that land-based anthropogenic activities have on marine ecosystems. Sediment and fauna samples from 13 stations along the whole coast of Cameroon were analyzed to assess the level of trace metal pollution in sediments and intertidal fauna. Sediments showed enrichment of As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn. However, pollution of greater concern was observed for Cd, Cr, Cu, Ni, and Zn at the northern stations. Some sites recorded trace metal levels higher than recommended in sediment quality guidelines. Species diversity was low, and high bioaccumulation of trace metals was observed in biological samples. Some edible gastropod species accumulated trace metals above the safety limits of the World Health Organization, European Medicine Agency, and the US Environment Protection Agency. Although industrial pollution is significant along Cameroon's coast, natural pollution from the volcano Mount Cameroon is also of concern. PMID:25957194

  16. Levels of PCBs and trace metals in Crab Orchard Lake sediment, benthos, zooplankton, and fish

    SciTech Connect

    Kohler, C.C.; Heidinger, R.C.; Call, T.

    1990-02-01

    Concentrations of trace metals and PCBs in six species of fish, zooplankton, macrobenthos, sediment, and water were studied in Crab Orchard Lake, Williamson County, Illinois. Eleven sites were chosen throughout the lake, including one site (site 10) near an abandoned dumpsite of a former electrical transformer manufacturing facility. PCB levels in the selected components from site 10 were considerably higher than the other sites. Thirty-eight percent (17/45) of fish fillets from various species at this site exceeded the 2.00 mg/kg FDA guideline for PCBs. PCB concentrations in fish were variable, and little relationship existed between age or size and PCB concentrations in most species. Common carp and channel catfish had higher PCB levels than the other species examined. Trace metals were low in fish and other components analyzed and were comparable to literature values for the midwestern United States. Mercury was the only trace metal to exhibit a significant positive relationship with age or size of fish. Mercury was also the only trace metal to exhibit biomagnification.

  17. TRACE METALS AND STATIONARY CONVENTIONAL COMBUSTION PROCESSES: VOLUME 1. TECHNICAL REPORT

    EPA Science Inventory

    The report gives results of a search of U.S. literature to identify published information about trace metals and Stationary Conventional Combustion Processes (SCCPs). The report summarizes the information found in the literature and includes specific references. It summarizes wha...

  18. Trace Metal Accumulation in Sediments and Benthic Macroinvertebrates before and after Maintenance of a Constructed Wetland

    EPA Science Inventory

    Periodic maintenance of stormwater best management practices (BMP) includes the removal of accumulated sediment. The resulting impact on trace metal concentrations of copper (Cu), lead (Pb), and zinc (Zn) in a constructed stormwater wetland BMP on Staten Island, NY was investiga...

  19. FATE AND TRANSPORT OF EMISSIONS FOR SEVERAL TRACE METALS OVER THE UNITED STATES

    EPA Science Inventory

    A regional model for atmospheric photochemistry and particulate matter is used to predict the fate and transport of five trace metals: lead, manganese, total chromium, nickel, and cadmium over the continental United States during January and July 2001. Predicted concentrations of...

  20. Continuous renal replacement therapy amino acid, trace metal and folate clearance in critically ill children

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We hypothesized that continuous veno-venous hemodialysis (CVVHD) results in amino acid, trace metals, and folate losses, thereby adversely impacting nutrient balance. Critically ill children receiving CVVHD were studied prospectively for 5 days. Blood concentrations, amino acids, copper, zinc, man...

  1. Record of the accumulation of sediment and trace metals in a Connecticut salt marsh

    SciTech Connect

    McCaffrey, R.J.; Thomson, J.

    1980-12-01

    The possibility that a useful, historical record of deposition might be found in a salt marsh is investigated by considering a record of the accumulation of sediment and trace metals in a Connecticut salt marsh. Evidence of salt-marsh deposition dominated by riverine runoff is presented.

  2. MARSH PLANTS AS VECTORS IN TRACE METAL TRANSPORT IN OREGON TIDAL MARSHES

    EPA Science Inventory

    The role of Pacific coast marsh plants as vectors in the flux of trace metals was studied in natural and perturbated situations. The flux of Cr, Cu, Fe, Mg, Sr, and Zn were studied in natural stands of Carex lyngbyei, Distichlis spicata, Potentilla pacifica, and Salicornia virgin...

  3. Complexation of trace metals by adsorbed natural organic matter

    USGS Publications Warehouse

    Davis, J.A.

    1984-01-01

    The adsorption behavior and solution speciation of Cu(II) and Cd(II) were studied in model systems containing colloidal alumina particles and dissolved natural organic matter. At equilibrium a significant fraction of the alumina surface was covered by adsorbed organic matter. Cu(II) was partitioned primarily between the surface-bound organic matter and dissolved Cu-organic complexes in the aqueous phase. Complexation of Cu2+ with the functional groups of adsorbed organic matter was stronger than complexation with uncovered alumina surface hydroxyls. It is shown that the complexation of Cu(II) by adsorbed organic matter can be described by an apparent stability constant approximately equal to the value found for solution phase equilibria. In contrast, Cd(II) adsorption was not significantly affected by the presence of organic matter at the surface, due to weak complex formation with the organic ligands. The results demonstrate that general models of trace element partitioning in natural waters must consider the presence of adsorbed organic matter. ?? 1984.

  4. Trends in trace organic and metal concentrations in the Pechora and Kara Seas and adjacent rivers

    SciTech Connect

    Brooks, J.M.; Champ, M.A.; Wade, T.L.; Kennicutt, M.C. II; Chambers, L.; Davis, T.

    1995-12-31

    Trace organic (pesticides, PCBs, PAHs and dioxin/furan) and trace metal concentrations have been measured in surficial sediment and tissue (i.e., clam, fish liver and flesh) samples from the Pechora and Kara Seas and their adjacent rivers -- Pechora, Ob and Yenisey Rivers. Total PAH, PCB and total DDT and chlordane concentrations ranged in surficial sediments from n.d. to 810 ppb, n.d.--8.7 ppb, n.d.--1.2 ppb, and n.d.--1.2 ppb, respectively, in a suite of 40 samples from the Kara Sea and its adjacent rivers. The highest concentrations of many of the trace organic and metal contaminants were found in the lower part of the Yenisey River below the salt wedge. Some trace metals (As for example) were elevated in the Pechora River dispositional plume region. Dioxin ranged from 1.36 to 413 ppt in a subset of 20 sediment samples. Higher trace organic contaminant concentrations compared to sediments were found in tissue samples from the region, especially fish liver samples. Concentrations as high as 1,114 ppb total PAHs, 89 ppb chlordane, 1,011 ppb for total DDT and 663 ppb PCBs were found in some fish liver samples. Dioxin concentrations in tissue samples ranged from 11.7 to 61 ppt. Concentrations of many trace organic and metal contaminants in these Russian marginal seas are influenced by inputs from these large Arctic rivers. Many organic contaminant concentrations in sediments are low, however detecting these compounds in tissue show they are bioavailable.

  5. Development of functional trait biomarkers for trace metal exposure in freshwater clams (Musculium spp.).

    PubMed

    Schoonover, Cody M; Wieker, Jessica; Pope, Rachelle; Brown, Chelsea; Cooper, Emily; DeWitt, Jariel; Gunselman, Samuel; Jensen, Cory; Stevens, Whitney; Yri, Jenae; Nezat, Carmen; Joyner-Matos, Joanna

    2016-10-01

    Exposure to trace metals typically causes oxidative stress; these consequences are better-characterized in estuarine and marine species than in freshwater species. How cellular-level responses to metal pollution influence whole-organism and population-level traits is poorly understood. We tested whether exposure to single metals (zinc and cadmium) and to metal mixtures (water in equilibrium with sediment from a highly polluted lake) alters two ecologically-relevant traits in freshwater clams, locomotion and reproduction. Fingernail clams (Musculium spp.) from unimpacted habitats were exposed to single metals and the metal mixture for up to 49days. The single metal doses (≤5mg/L Zn and ≤20μg/L Cd) were not toxicologically meaningful as clam survival, burial, and climbing activity did not differ across treatments. Water in equilibrium with the lake sediment contained cadmium, copper, lead, and zinc. Clams exposed to this metal mixture had decreased climbing activity but no change in burial activity. Metal-exposed clams had lower fecundity (number of shelled juveniles extruded by adult clams) and patterns in metal accumulation corresponded with lake sediment dose and clam activity. In contrast to the functional traits, stress protein expression and whole-clam glycogen content did not vary across treatment groups. These results indicate that fingernail clams of the genus Musculium are appropriate for development as sentinel species for metal pollution and can serve as a model for determining how metal pollution alters metabolic allocation patterns in freshwater organisms. PMID:27085374

  6. Sedimentary Trace Metal-Organic Interactions as Proxies for Oceanic Redox Conditions

    NASA Astrophysics Data System (ADS)

    Cruse, A. M.; Lyons, T. W.; Hannigan, R.

    2007-12-01

    Knowledge of trace-metal partitioning in oceanic sediments (e.g., Fe, Mo, U, Zn) are requisite to the construction of accurate models of geochemical cycling in modern and ancient waters. Factors such as oxygen penetration depth and bottom-water redox; sedimentation rate; and supply of reactants, such as dissolved sulfide, are known to affect metal sequestration in and remobilization from coastal sediments. In addition to these factors, the flux of organic carbon (OC) and the composition of this carbon are also a key in the sequestration of these metals. Currently, however, there is an absence of quantitative information on the mass balance of metals fixed in coastal sediments through direct interactions with OC, how OC remineralization affects this mass balance, and the specific nature of the metal-OC relationship. To address these issues, we have undertaken a field-based study to test the hypothesis that porewater redox conditions are recorded in the concentrations of trace metals bound in the sedimentary OC pool. We have collected sediments from several modern anoxic/euxinic basins: the central Black Sea, the Orca Basin, the Cariaco Basin, and Effingham Inlet (Vancouver Island). These environments vary in terms of dissolved sulfide concentrations and sedimentary iron sulfide geochemistry. Additionally, the sediments are characterized by a range in OC concentrations, and proximity to terrestrial sources. Extractable organic carbon was characterized with gas chromatography, and OC-bound metals are quantified using high-performance liquid chromatography- inductively coupled mass spectrometry. The preliminary results suggest that variations in the ratios of aromatic to saturate hydrocarbons may control the speciation of metals in the organic carbon pool. Bottomwater redox may be one factor controlling this relationship, although it is currently unclear if this is due to variations in metal speciation or the direct involvement of S in the OC-metal reaction mechanism

  7. Trace metal concentrations are higher in cartilage than in bones of scaup and pochard wintering in Poland.

    PubMed

    Kalisińska, Elzbieta; Salicki, Wiesław; Kavetska, Katarzyna M; Ligocki, Marek

    2007-12-15

    Bones and cartilage of two species of diving ducks: the scaup Aythya marila (n=24) and the pochard A. ferina (n=24) were studied. Scaup is protected in Poland where it spends only the winter, while pochard is a game bird, abundant and breeding in Poland. In winter, the two species form large flocks off the southern coast of the Baltic, particularly in the Szczecin Lagoon where they were collected for this study. The bones and cartilage (trachea) were assayed for concentrations (dry weight-based) of three essential metals: iron (Fe), copper (Cu), and zinc (Zn); concentrations of the two toxic metals: lead (Pb) and cadmium (Cd) were assayed as well. These hard tissues of the two species showed the following order of metal concentrations Zn>Fe>Pb>Cu>Cd. In scaup and pochard bones, the respective geometric mean concentrations of Zn, Fe, Pb, Cu, and Cd were 94.4 and 102.0; 20.2 and 24.7; 6.2 and 9.6; 0.19 and 0.26; 0.114 and 0.162 mg/kg. The levels of all the metals in cartilage (Zn 149.1 and 165.8; Fe 58.4 and 116.3; Pb 10.6 and 14.9; Cu 1.41 and 3.31; Cd 0.144 and 0.175 mg/kg, respectively) were higher than in the bones of A. marila and A. ferina. However, statistically significant differences were found in respect to the essential metals only (Zn, Fe, Cu). The inter-species comparisons showed the two species to differ in their cartilage concentrations of Fe, Cu, Zn, and Cd and in their bone concentrations of Pb and Cd. In each case, the pochard exhibited higher concentrations of metals. This study showed distinct differences between trace element accumulation by two heavily mineralised avian body parts: leg bones (tarsometatarsus) and cartilage (trachea). The results are in agreement with data reported by other workers who analysed trace metals in cartilaginous and bone components of the femoral head in homoiotherm vertebrates, including humans. Therefore it is important that intra- and inter-species comparisons of hard biological components be based on corresponding

  8. Contamination characteristics and source apportionment of trace metals in soils around Miyun Reservoir.

    PubMed

    Chen, Haiyang; Teng, Yanguo; Chen, Ruihui; Li, Jiao; Wang, Jinsheng

    2016-08-01

    Due to their toxicity and bioaccumulation, trace metals in soils can result in a wide range of toxic effects on animals, plants, microbes, and even humans. Recognizing the contamination characteristics of soil metals and especially apportioning their potential sources are the necessary preconditions for pollution prevention and control. Over the past decades, several receptor models have been developed for source apportionment. Among them, positive matrix factorization (PMF) has gained popularity and was recommended by the US Environmental Protection Agency as a general modeling tool. In this study, an extended chemometrics model, multivariate curve resolution-alternating least squares based on maximum likelihood principal component analysis (MCR-ALS/MLPCA), was proposed for source apportionment of soil metals and applied to identify the potential sources of trace metals in soils around Miyun Reservoir. Similar to PMF, the MCR-ALS/MLPCA model can incorporate measurement error information and non-negativity constraints in its calculation procedures. Model validation with synthetic dataset suggested that the MCR-ALS/MLPCA could extract acceptable recovered source profiles even considering relatively larger error levels. When applying to identify the sources of trace metals in soils around Miyun Reservoir, the MCR-ALS/MLPCA model obtained the highly similar profiles with PMF. On the other hand, the assessment results of contamination status showed that the soils around reservoir were polluted by trace metals in slightly moderate degree but potentially posed acceptable risks to the public. Mining activities, fertilizers and agrochemicals, and atmospheric deposition were identified as the potential anthropogenic sources with contributions of 24.8, 14.6, and 13.3 %, respectively. In order to protect the drinking water source of Beijing, special attention should be paid to the metal inputs to soils from mining and agricultural activities. PMID:27107989

  9. Assessment of trace metals in four bird species from Korea.

    PubMed

    Kim, Jungsoo; Oh, Jong-Min

    2013-08-01

    In birds, heavy metal concentrations are influenced by diet intake, migratory pattern, and residence time. In the present study, heavy metal concentrations (in microgram per gram dry weight) were measured in livers of four bird species from Korea. Iron concentrations were greater in Eurasian Woodcocks (Scolopax rusticola) than in Grey Herons (Ardea cinerea), Little Egrets (Egretta garzetta), and Schrenck's Bitterns (Ixobrychus eurhythmus). Copper concentrations in Grey Herons were significantly higher than in other species. Lead concentrations were greater in Schrenck's Bitterns and Eurasian Woodcocks than in Grey Herons and Little Egrets. Eurasian Woodcocks had higher cadmium concentrations than in other species. Zinc and manganese concentrations did not differ among species. Iron, zinc, manganese, and copper concentrations from this study were within the range of other Korean bird studies, and these concentrations were far below toxic levels. Cadmium and lead accumulation trends in each species were different, and the results might be associated with their migration pattern and residence time in Korea. Grey Herons, Little Egrets, and Schrenck's Bitterns are usually summer visitors, and Eurasian Woodcocks are passage migrants. But herons and egrets were collected in spring, autumn, and winter, but not during breeding season. They might be residents, so they could more reflect Korean cadmium and lead contaminations than Schrenck's Bitterns. However, Eurasian Woodcocks could more reflect habitats outside Korea because of their short staying time in Korea. PMID:23430066

  10. Trace metals dynamics in surface sediments investigated by DGT micro-scale measurements

    NASA Astrophysics Data System (ADS)

    Motelica-Heino, M.; Davison, W.

    2003-05-01

    In surface sediments, metal mobility is controlled by the recruitment and turn-over of organic matter whereas sulphide is thought to control the concentration of metals in sediment pore water by removing them from the solution. DGT is a dynamic probe that measures the kinetically available fraction of metals or sulphide. DGT uses a credit card size probe inserted into the sediment that provides a snapshot of the metal distribution in the sediment, which can be uncovered by spectrochemical analytical techniques. In-situ vertical profiles and horizontal maps of trace metals at high (mm scale) and ultra-high resolution (100 μm) together with Fe, Mn and sulphide were generated from DGT probes deployed in surface sediments. Collectively, the results showed that besides vertical gradients, associated with the depletion of oxygen with depth and the degradation of organic matter by a succession of electron acceptors, small scale remobilisation of metals associated with sediment heterogeneity take place.

  11. Biogeochemical and hydrological controls on fate and distribution of trace metals in oiled Gulf salt marshes

    NASA Astrophysics Data System (ADS)

    Keevan, J.; Natter, M.; Lee, M.; Keimowitz, A.; Okeke, B.; Savrda, C.; Saunders, J.

    2011-12-01

    On April 20, 2010, the drilling rig Deepwater Horizon exploded in the Gulf of Mexico, resulting in the release of approximately 5 million barrels of crude oil into the environment. Oil and its associated trace metals have been demonstrated to have a detrimental effect on coastal wetland ecosystems. Wetlands are particularly susceptible to oil contamination because they are composed largely of fine-grained sediments, which have a high capacity to adsorb organic matter and metals. The biogeochemical cycling of trace metals can be strongly influenced by microbial activity, specifically those of sulfate- and iron-reducing bacteria. Microbial activity may be enhanced by an increase in amounts of organic matter such as oil. This research incorporates an assessment of levels of trace metals and associated biogeochemical changes from ten coastal marshes in Alabama, Mississippi, and Louisiana. These sampling sites range in their pollution levels from pristine to highly contaminated. A total digestion analysis of wetland sediments shows higher concentrations of certain trace metals (e.g., Ni, Cu, Pb, Zn, Sr, Co, V, Ba, Hg, As) in heavily-oiled areas compared to less-affected and pristine sites. Due to chemical complexation among organic compounds and metals, crude oils often contain elevated levels (up to hundreds of mg/kg) of trace metals At the heavily-oiled Louisiana sites (e.g., Bay Jimmy, Bayou Dulac, Bay Batiste), elevated levels of metals and total organic carbon have been found in sediments down to depths of 30 cm. Clearly the contamination is not limited to shallow sediments and oil, along with various associated metals, may be invading into deeper (pre-industrial) portions of the marsh sediments. Pore-waters extracted from contaminated sediments are characterized by very high levels of reduced sulfur (up to 80 mg/kg), in contrast to fairly low ferrous iron concentrations (<0.02 mg/kg). The influx of oil into the wetlands might provide the initial substrate and

  12. The Effect of Helicobacter pylori Eradication on the Levels of Essential Trace Elements

    PubMed Central

    Wu, Meng-Chieh; Huang, Chun-Yi; Kuo, Fu-Chen; Hsu, Wen-Hung; Wang, Sophie S. W.; Shih, Hsiang-Yao; Liu, Chung-Jung; Chen, Yen-Hsu; Wu, Deng-Chyang; Huang, Yeou-Lih; Lu, Chien-Yu

    2014-01-01

    Objective. This study was designed to compare the effect of Helicobacter pylori (H. pylori) infection treatment on serum zinc, copper, and selenium levels. Patients and Methods. We measured the serum zinc, copper, and selenium levels in H. pylori-positive and H. pylori-negative patients. We also evaluated the serum levels of these trace elements after H. pylori eradication. These serum copper, zinc, and selenium levels were determined by inductively coupled plasma mass spectrometry. Results. Sixty-three H. pylori-positive patients and thirty H. pylori-negative patients were studied. Serum copper, zinc, and selenium levels had no significant difference between H. pylori-positive and H. pylori-negative groups. There were 49 patients with successful H. pylori eradication. The serum selenium levels were lower after successful H. pylori eradication, but not significantly (P = 0.06). There were 14 patients with failed H. pylori eradication. In this failed group, the serum selenium level after H. pylori eradication therapy was significantly lower than that before H. pylori eradication therapy (P < 0.05). The serum zinc and copper levels had no significant difference between before and after H. pylori eradication therapies. Conclusion. H pylori eradication regimen appears to influence the serum selenium concentration (IRB number: KMUH-IRB-20120327). PMID:25548772

  13. Speciation and Distribution of Trace Metals Associated with Iron Sulfides in the Marcellus Shale

    NASA Astrophysics Data System (ADS)

    Singer, D. M.; Cahill, M.

    2014-12-01

    Black shales underlying the areas from Eastern Ohio, through Pennsylvania, and into Central New York State have become of economic interest lately due to the recent economic viability of shale gas extraction. Sulfide minerals such as pyrite and marcasite occurring in these shales are often the primary phases that trace metals are associated with. Trace metals can be incorporated into these sulfides via various pathways during initial shale deposition and secondary diagenesis including substitution for Fe (Co and Ni), substitution for S (As and Se), and excluded to form other sulfide phases (Cu and Zn). The manner in which these trace metals are incorporated directly influences how they are released into the environment during sulfide oxidation following shale weathering or hydraulic fracturing. The aim of this research is to examine the distribution of trace metals in iron sulfides from black shales using Synchrotron-based X-ray microprobe techniques including micro-X-ray fluorescence and micro-X-ray diffraction of shale thin sections. Marcellus Shale samples were collected from: (1) outcrops from the Oatka member in Leroy, NY and Jersey Shore, PA and the Union Springs member in Lewiston, PA, and (2) drilling core sample from Beaver Meadow, NY and Hancock Co, TN (Chattanooga shale). Analyses have shown that the sulfide grains are a combination of pyrite and marcasite. As and Se are spatially correlated with each other and within the pyrite grains. Ni is spatially correlated with larger euhedral pyrite, as well as smaller non-iron sulfide grains. Cu and Zn are not spatially correlated with the pyrite and form separate Cu- and Zn- sulfides. During iron sulfide oxidative dissolution, these differences in distribution of trace metals will affect the order and rate in which they are released into the environment.

  14. Sediment properties and trace metal pollution assessment in surface sediments of the Laizhou Bay, China.

    PubMed

    Xu, Gang; Liu, Jian; Pei, Shaofeng; Gao, Maosheng; Hu, Gang; Kong, Xianghuai

    2015-08-01

    Spatial distribution, ecological risk, pollutant source, and transportation of trace metals in surface sediments, as well as the sediment properties, were analyzed in this study to assess the pollution status of trace metal in the Laizhou Bay, China. Results of provenance analyses indicate that surface sediments were primarily from weathering products carried by the surrounding short rivers and partially from loess matters carried by the Yellow River. Variations of trace metal concentrations were mostly controlled by the accumulation of weathering products, organic matters, and the hydrodynamics. Geoaccumulation index suggests that no Cr pollution occurred in the study area, and Cu, Pb, and Zn pollutions appeared only at a few stations. Comparatively, Cd and As pollutions were at noticeably weak to moderate level at many stations. The combination of six trace metals in this study had a 21% probability of being toxic in our study area based on sediment quality guidelines. Enrichment factors (EFs) and statistical analyses indicate that Cu, Pb, and Zn were primarily derived from the natural process of weathering. By contrast, Cd, As, and Cr (especially Cd and As) were provided by the anthropogenic activities to a large extent. Due to the dilution of coarse-grained sediments, there was even no contamination at some of stations that were obviously influenced by humans. Based on the current study of transportation process of fine-grained sediments in combination with the spatial distribution of EFs, it is found that the migration of anthropogenic trace metals was mainly controlled by the tide in the Laizhou Bay. The study suggests that an effective strategies and remedial measures should be designed and undertaken to prevent further anthropogenic Cd and As pollutions in this area in the future. PMID:25847442

  15. The geochemistry of redox sensitive trace metals in sediments

    SciTech Connect

    Morford, J.L.; Emerson, S.

    1999-06-01

    The authors analyzed the redox sensitive elements V, Mo, U, Re and Cd in surface sediments from the Northwest African margin, the US Northwest margin and the Arabian Sea to determine their response under a range of redox conditions. Where oxygen penetrates 1 cm or less into the sediments, Mo and V diffuse to the overlying water as Mn is reduced and remobilized. Authigenic enrichments of U, Re and Cd are evident under these redox conditions. With the onset of sulfate reduction, all of the metals accumulate authigenically with Re being by far the most enriched. General trends in authigenic metal accumulation are described by calculating authigenic fluxes for the 3 main redox regimes: oxic, reducing where oxygen penetrates {le} 1 cm, and anoxic conditions. Using a simple diagenesis model and global estimates of organic carbon rain rate and bottom water oxygen concentrations, the authors calculate the area of sediments below 1,000 m water depth in which oxygen penetration is {le} 1 cm to be 4% of the ocean floor. They conclude that sediments where oxygen penetrates {le} 1 cm release Mn, V and Mo to seawater at rates of 140%--260%, 60%--150% and 5%--10% of their respective riverine fluxes, using the authigenic metal concentrations and accumulation rates from this work and other literature. These sediments are sinks for Re, Cd and U, with burial fluxes of 70%--140%, 30%--80% and 20%--40%, respectively, of their dissolved riverine inputs. They modeled the sensitivity of the response of seawater Re, Cd and V concentrations to changes in the area of reducing sediments where oxygen penetrates {le} 1 cm. The analysis suggests a negligible change in seawater Re concentration, whereas seawater concentrations of Cd and V could have decreased and increased, respectively, by 5%--10% over 20 kyr if the area of reducing sediments increased by a factor of 2 and by 10%--20% if the area increased by a factor of 3. The concentration variations for a factor of 2 increase in the area of

  16. Sediment concentrations of trace metals in the Berre lagoon (France): an assessment of contamination.

    PubMed

    Accornero, Alessandra; Gnerre, Rossella; Manfra, Loredana

    2008-04-01

    This paper reports the concentrations of eight trace metals (Cr, Zn, Cu, Pb, Ni, As, Cd, and Hg) in the surficial sediments of the Berre lagoon. This is a typical Mediterranean lagoon, seriously affected by human activities since the 1930s, when it became one of the most important industrial sites in France. The overall range of concentrations is 38-428 mg kg(-1) for chromium, 50-151 mg kg(-1) for zinc, 11-48 mg kg(-1) for copper, 18-82 mg kg(-1) for lead, 18-56 mg kg(-1) for nickel, 4-10 mg kg(-1) for arsenic, 0.2-1.6 mg kg(-1) for cadmium, and 0.15-0.40 mg kg(-1) for mercury. The spatial distribution of concentrations largely mirrors the localization of major impact sources, with the most affected area restricted to a radius of a few kilometers from point sources, due to the environmental conditions of the outfall zone (fine sediments, low hydrodynamic regime, confinement), which favor the in situ accumulation of pollutants. The extent of contamination from trace metals in the lagoon sediments is evaluated through a three-pronged approach: (i) by comparison with other areas (see Table 3 for an up-to-date review of trace metal concentrations in lagoon systems and coastal regions of the world ocean); (ii) by evaluating the metal enrichment in the sediments through the calculation of concentration factors (CF) for each trace metal and by combining the CFs to estimate a Metal Pollution Index (MPI) taking into account the differences in toxicity of trace metals; and (iii) by defining a potential level of biological risk by the use of quality criteria such as the Threshold Effect Level (TEL) and Effects Range-Low (ER-L) benchmarks. On the basis of the calculated CFs, sediments appear as particularly enriched with Pb and Cd throughout the lagoon and with Cr and Zn at some sites. Although no site can be classified as "unpolluted" when looking at the calculated MPIs, two regions--the Vaïne pond and the southwestern area--have been identified as critical points of

  17. Trace metals and otolith defects in mocha mice.

    PubMed

    Rolfsen, R M; Erway, L C

    1984-01-01

    Mocha mice with pigment anomalies of the coat, eyes, and inner ears also have congenital otolith defects, and they exhibit progressive cochlear degeneration. Mocha mice were first reported to exhibit otolith defects comparable to those of pallid mice. Since manganese supplementation is effective in preventing the otolith defects in pallid mice and in pastel mink, we sought to establish whether or not manganese also might be effective in mocha mice. The otolith defects of mocha mice were prevented or reduced by supplementing the pregnant dams with manganese and/or zinc. The mocha mice also exhibited high perinatal mortality that was not reduced by the supplementary metals. Surviving mocha mice have behavioral anomalies associated with their inner ear defects. Preliminary observations of auditory-evoked brainstem responses and of cochlear degeneration in the mocha mice are discussed. PMID:6736600

  18. Relationship between gastric cancer and blood trace metal levels

    SciTech Connect

    Saito, K.; Fujimoto, S.; Sasaki, T.; Kurasaki, M.; Kaji, H.

    1981-06-01

    The metal concentrations in whole blood, blood plasma and blood cells of the patients were compared with those of normal subjects. Significantly lower levels of Cd, Mn, Pb and Zn in whole blood of the patients were found. The Cu levels in the blood cells and Zn levels in the blood plasma of patients were of definitely lower levels than those of the normal subjects. Superoxide dismutase (SOD), catale (CAT), glutathione peroxidase (GPX) and delta aminolevulinic dehydratase (ALAD) metal enzymes were assayed in the 30 patients and in 24 normal subjects matches in age to the patients. SOD levels in blood cells of the patients were definitely lower than those of the normal subjects. The CAT activities showed a significantly higher level in the stage II and a significantly lower level in the stage IV and metastatic groups. The activities of GPX and ALAD did not show any significant difference between the patients with gastric cancer and the normal subjects. There were significant negative correlations between CAT activity in whole blood and Cu level in whole blood and blood plasma; also, positive correlations between Zn level and in whole blood and CAT activity, and between Zn level and GPX activity in patients with gastric cancer. Moreover there were positive correlations between Zn level and SOD level in the blood cells and also a negative correlation between Zn level in blood cells and GPX activity in whole blood. These correlations suggested that there may be some important relationship between the metabolism of superoxide anion in gastric cancer patients and advanced cancer.

  19. Sensitivity of juvenile freshwater crayfish Cherax destructor (Decapoda: Parastacidae) to trace metals.

    PubMed

    Khan, Shahnaz; Nugegoda, Dayanthi

    2007-11-01

    Juvenile Cherax destructor was investigated as a potential test species for toxicity testing of trace metals in Australian freshwater systems. Adult male and female C. destructor were bred in the laboratory to obtain 4-week old juveniles, which were used in the toxicity tests. Animals were exposed to a range of concentrations of the trace metals ions copper (377-1275 microg/L), cadmium (377-1275 microg/L), nickel (300-1013 mg/L) and iron (36-168 mg/L) in static-renewal 96-h bioassays. The 96-h LC50 value for cadmium was 379, 494 microg/L for copper, 50 mg/L for iron and 327 mg/L for nickel demonstrating a decreasing toxicity of these metals to C. destructor. Comparison of LC50 values for metals for this species with those for other aquatic organisms reveals that C. destructor is less sensitive to trace metals than most other tested species. PMID:17011034

  20. Trace metal partitioning in caustic calcined magnesia produced from natural magnesite.

    PubMed

    Chimenos, J M; Fernández, A I; Haurie, L; Calaf, M

    2012-01-01

    Caustic calcined magnesia from natural magnesite has been widely employed as a source of magnesium. This mineral, depending on the origin, may contain heavy metals and metalloids that can exceed the regulatory limits in some applications. In most cases, heavy metals and metalloids form solid solutions with the mineral phases of the main impurities, or even magnesium oxide itself, replacing other ions in the crystal lattice. Compared with magnesium oxide, most of these impurities such as silica and silicates are much more chemically stable even in concentrated mineral acids under normal temperature and pressure conditions. In this study, the partitioning of the trace metals was monitored using a sequential extraction procedure (SEP), and their potential solubility was determined using the pH-static leaching test. Only a small fraction of magnesium oxide derived from heavily calcined magnesia is soluble in slightly acidic media. The release of the trace metals and metalloids contained in the soluble fractions was less than 40% as determined by total digestion. It can be concluded that SEP is more accurate than total chemical digestion for setting the maximum limits of the undesirable trace metals. PMID:22217087

  1. Transplanted aquatic mosses for monitoring trace metal mobilization in acidified streams of the Vosges Mountains, France

    SciTech Connect

    Mersch, J.; Guerold, F.; Rousselle, P.; Pihan, J.C. )

    1993-08-01

    As a result of acid depositions, trace metals are mobilized from the soils to the aquatic environment. Especially in poorly mineralized waters, elevated metal concentrations may rapidly have adverse effects on aquatic organisms. In particular, it has been shown that aluminium, a key element in the acidification process, is a toxic cofactor for fish and other biota. An accurate assessment of this specific form of water pollution may not be possible when only based on analyses of single water samples. On the one hand, water metal concentrations are often close to the detection limit of usual analytical techniques, and on the other hand, levels in acidified streams undergo strong temporal variations caused by acid pulses following meteorological events such as heavy rainfall and snowmelt. Compared to water analyses, indirect monitoring methods provide undeniable advantages for assessing water contamination. Aquatic bryophytes, in particular, have been regarded as interesting indicator organisms for trace metal pollution. However, their use has mainly been restricted to the lower course of streams for evaluating the impact of industrial discharges. The purpose of this study was to test the suitability of transplanted aquatic mosses for monitoring aluminium and four other trace metals (copper, iron, lead and zinc) in the particular context of acidifed streams draining a forested headwater catchment. 15 refs., 2 figs., 2 tabs.

  2. Source Evaluation and Trace Metal Contamination in Benthic Sediments from Equatorial Ecosystems Using Multivariate Statistical Techniques

    PubMed Central

    Benson, Nsikak U.; Asuquo, Francis E.; Williams, Akan B.; Essien, Joseph P.; Ekong, Cyril I.; Akpabio, Otobong; Olajire, Abaas A.

    2016-01-01

    Trace metals (Cd, Cr, Cu, Ni and Pb) concentrations in benthic sediments were analyzed through multi-step fractionation scheme to assess the levels and sources of contamination in estuarine, riverine and freshwater ecosystems in Niger Delta (Nigeria). The degree of contamination was assessed using the individual contamination factors (ICF) and global contamination factor (GCF). Multivariate statistical approaches including principal component analysis (PCA), cluster analysis and correlation test were employed to evaluate the interrelationships and associated sources of contamination. The spatial distribution of metal concentrations followed the pattern Pb>Cu>Cr>Cd>Ni. Ecological risk index by ICF showed significant potential mobility and bioavailability for Cu, Cu and Ni. The ICF contamination trend in the benthic sediments at all studied sites was Cu>Cr>Ni>Cd>Pb. The principal component and agglomerative clustering analyses indicate that trace metals contamination in the ecosystems was influenced by multiple pollution sources. PMID:27257934

  3. Assessment of trace metal toxicity in soils of Raniganj Coalfield, India.

    PubMed

    Das, Supriyo Kumar; Chakrapani, Govind J

    2011-06-01

    Soil, rock and water samples were collected from India's oldest coalfield Raniganj to investigate trace metal contamination from mining activity. Our data reveal that trace metal concentration in soil samples lies above the average world soil composition; especially, Cr, Cu, Ni and Zn concentrations exceed the maximum allowable concentration proposed by the European Commission for agricultural soils. In particular, Cr, Cu and Ni exceed the ecotoxicological limit, and Ni exceeds the typical value for cultivated soils. Mineral dissolution from overburden material and high adsorption capacity of laterite soil are responsible for the elevated concentrations. This is evident from enrichment factor (E (f)), geoaccumulation index (I (geo)) and metal pollution index values. Sediment quality guideline index indicates toxicity to local biota although enrichment index suggests no threat from consuming crops cultivated in the contaminated soil. PMID:20661770

  4. Depth profiling (ICP-MS) study of trace metal 'grains' in solid asphaltenes.

    PubMed

    Pillay, Avin E; Bassioni, Ghada; Stephen, Sasi; Kühn, Fritz E

    2011-08-01

    Knowledge of trace metal 'grains' in asphaltenes could play a significant role in enhancing refining and processing of crudes and also in providing useful information on mechanistic and migratory features linked to asphaltenes. These metals originate directly from interaction of oils with source-rock, mineral matter, and formation water and their accumulation in asphaltene matrices could vary from oil well to oil well. Suitable asphaltene samples were subjected to high-performance ICP-MS laser depth profiling (213 nm) to depths of 50 μm at 5 μm intervals. The study was conducted in the absence of standardization and characteristic intensities originating from the metals of interest were measured. Ten metal profiles were investigated (Na, Mg, Al, Mn, Fe, Zn, Sr, Pb, V, and Ni). The experimental results showed non-uniform distribution of trace metals and identified areas where such metals agglomerate. The data suggested that certain chemical and physical conditions within the structure of asphaltenes are favorable for metal 'grain' formation at specific points. The exact mechanism for this behavior is not clear at this stage, and has considerable scope for future studies, including mathematical modeling simulations of asphaltenes. We also found that solid asphaltenes could be a useful forerunner of scale formation. PMID:21953195

  5. Bioavailability of Sodium and Trace Metals under Direct and Indirect Effects of Compost in Urban Soils.

    PubMed

    Kargar, Maryam; Clark, O Grant; Hendershot, William H; Jutras, Pierre; Prasher, Shiv O

    2016-05-01

    The contamination of urban soil with sodium (Na) and trace metals can be one of the major concerns for groundwater contamination and street tree health. The bioavailability of Na, copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb) in urban soil amended with 0, 5, and 10% w/w compost was evaluated at none, medium, and high contamination levels of soil mixtures. The relationship between soil properties, compost addition, contamination level and metal uptake by barley ( L.) was determined using multivariate linear regression and path analysis. The results indicated the direct negative effect of compost on metal absorption possibly through specific complexation for Cu, Zn, Cd, and Pb. Compost can also affect the absorption of Na and Cd indirectly by means of cation exchange capacity (CEC) and pH. The degree of soil contamination with metals can affect the competition of cations for the complexing sites of the soil mixtures and, therefore, can induce changes in metal availability for plants. Compost addition to the soil also increased nutrient availability, except for ammonium (NH) and nitrate (NO). We concluded that in the short term, the addition of compost significantly reduced metal bioavailability and improved nutrient availability. However, more studies are required to monitor the long-term ability of the compost to reduce Na and trace metal bioavailability in urban soil. PMID:27136168

  6. Mercury and trace metal partitioning and fluxes in suburban Southwest Ohio watersheds.

    PubMed

    Naik, Avani P; Hammerschmidt, Chad R

    2011-10-15

    Many natural watersheds are increasingly affected by changes in land use associated with suburban sprawl and such alterations may influence concentrations, partitioning, and fluxes of toxic trace metals in fluvial ecosystems. We investigated the cycling of mercury (Hg), monomethylmercury, cadmium, copper, lead, nickel, and zinc in three watersheds at the urban fringe of Dayton, Ohio, over a 13-month period. Metal concentrations were related positively to discharge in each stream, with each metal having a high affinity for suspended particles and Hg also having a noticeable association with dissolved organic carbon. Although not observed for the other metals, levels of Hg in river water varied seasonally and among streams. Yields of Hg from two of the catchments were comparable to that predicted for runoff of atmospherically deposited Hg (∼25% of wet atmospheric flux), whereas the third watershed had a significantly greater annual flux associated with greater particle-specific and filtered water Hg concentrations, presumably from a point source. Fluxes of metals other than Hg were similar among each watershed and suggestive of a ubiquitous source, which could be either atmospheric deposition or weathering. Results of this study indicate that, with the exception of Hg being increased in one watershed, processes affecting metal partitioning and loadings are similar among southwest Ohio streams and comparable to other North American rivers that are equally or less impacted by urban development. Relative differences in land use, catchment area, and presence or absence of waste water treatment facilities had little or no detectable effect on most trace metal concentrations and fluxes. This suggests that suburban encroachment on agricultural and undeveloped lands has either similarly or not substantially impacted trace metal cycling in streams at the urban fringe of Dayton and, by extension, other comparable metropolitan areas. PMID:21827962

  7. Evaluation of Toxic Metals and Essential Elements in Children with Learning Disabilities from a Rural Area of Southern Brazil

    PubMed Central

    do Nascimento, Sabrina Nunes; Charão, Mariele Feiffer; Moro, Angela Maria; Roehrs, Miguel; Paniz, Clovis; Baierle, Marília; Brucker, Natália; Gioda, Adriana; Barbosa, Fernando; Bohrer, Denise; Ávila, Daiana Silva; Garcia, Solange Cristina

    2014-01-01

    Children’s exposure to metals can result in adverse effects such as cognitive function impairments. This study aimed to evaluate some toxic metals and levels of essential trace elements in blood, hair, and drinking water in children from a rural area of Southern Brazil. Cognitive ability and δ-aminolevulinate dehydratase (ALA-D) activity were evaluated. Oxidative stress was evaluated as a main mechanism of metal toxicity, through the quantification of malondialdehyde (MDA) levels. This study included 20 children from a rural area and 20 children from an urban area. Our findings demonstrated increase in blood lead (Pb) levels (BLLs). Also, increased levels of nickel (Ni) in blood and increase of aluminum (Al) levels in hair and drinking water in rural children were found. Deficiency in selenium (Se) levels was observed in rural children as well. Rural children with visual-motor immaturity presented Pb levels in hair significantly increased in relation to rural children without visual-motor immaturity (p < 0.05). Negative correlations between BLLs and ALA-D activity and positive correlations between BLLs and ALA-RE activity were observed. MDA was significantly higher in rural compared to urban children (p < 0.05). Our findings suggest that rural children were co-exposed to toxic metals, especially Al, Pb and Ni. Moreover, a slight deficiency of Se was observed. Low performance on cognitive ability tests and ALA-D inhibition can be related to metal exposure in rural children. Oxidative stress was suggested as a main toxicological mechanism involved in metal exposure. PMID:25329533

  8. Trace metals in Antarctica related to climate change and increasing human impact.

    PubMed

    Bargagli, R

    2000-01-01

    Metals are natural constituents of the abiotic and biotic components of all ecosystems, and under natural conditions they are cycled within and between the geochemical spheres--the atmosphere, lithosphere, hydrosphere, and biosphere--at quite steady fluxes. In the second half of the twentieth century, the huge increase in energy and mineral consumption determined anthropogenic emissions of several metals exceeding those from natural sources, e.g., volcanoes and windborne soil particles. In the Northern Hemisphere, the biogeochemical cycles of Pb, Cd, Zn, Cu, and other metals were significantly altered, even in Arctic regions. On the contrary, available data on trace metal concentrations in abiotic matrices from continental Antarctica, summarized in this review, suggest that the biogeochemical cycle of Pb is probably the only one that has been significantly altered by anthropogenic emissions in Antarctica and elsewhere in the Southern Hemisphere, especially in the period 1950-1975. Environmental contamination by other metals from anthropogenic sources in Antarctica itself can generally only be detected in snow samples taken within a range of a few kilometers or several hundred meters from scientific stations. Local metal pollution from human activities in Antarctica may compromise studies aimed at assessing the biogeochemical cycle of trace elements and the effects of global climate change. Thus, this review focuses on concentrations of metals in atmospheric particulate, snow, surface soils, and freshwater from the Antarctic continent and surface sediments and seawater from the Southern Ocean, which can plausibly be regarded as global background values of trace elements. These baselines are also necessary in view of the construction of new stations, the expansion of existing facilities to support research, and the growth of tourism and fisheries. Despite difficulties in making comparisons with data from other remote areas of the world, concentrations of trace metals

  9. Geographic distribution of arsenic and trace metals in lotic ecosystems of the Pampa Plain, Argentina.

    PubMed

    Rosso, Juan José; Troncoso, Juan José; Fernández Cirelli, Alicia

    2011-01-01

    In this paper, the geographic distribution of arsenic and other trace elements in surface waters of 39 lotic ecosystems of central Argentina was evaluated. Manganese and arsenic were the most conspicuous elements, being present in 82% and 59% of the sampled ecosystems of this region, respectively. As concentration averaged 113.69 μg L⁻¹ varying between 55 and 198 μg L⁻¹, other trace elements were hardly detected or not detected at all. It was remarkable the absence of detectable concentrations of anthropogenically derived metals as lead (Pb) and cadmium (Cd). PMID:21153802

  10. Distribution of dissolved and particulate trace metals in Arctic sea ice

    NASA Astrophysics Data System (ADS)

    Taylor, M.; Hendy, I. L.; Aciego, S.; Meyer, K.

    2014-12-01

    Iron (Fe) is an essential biolimiting micronutrient, however, the bioavailablility of Fe is dependent on source and speciation. In a high nutrient/low chlorophyll region of the ocean such as the Arctic, sea ice is an important aggregator of dissolved and particulate Fe from aerosol, lithogenic, and biogenic sources. While particulate Fe is less bioavailable than dissolved Fe, it is far more abundant in sea ice. As a result, sea ice directly enhances productivity by ice entrapment of mineral dust particulates containing Fe, which can be released into the surface ocean waters during melting. In seawater underlying sea ice, Fe can be concentrated up to two orders of magnitude higher than in the ice-free open ocean (Lannuzel et al., 2011). A transect of sea ice cores were collected in the spring of 2014 offshore of Barrow, AK, and the Canadian Arctic Archipelago to capture a gradient of sediment contributions from shelf sediments to aeolian sediments. At Barrow, AK, land fast first year ice was sampled. In the Canadian Arctic, both multi-year (pack ice) and first year (land fast) ice cores were retrieved. First year ice cores were between 100-150 cm thick and the multi year core was 195 cm thick. Cores were subsampled by depth and filtered. The resulting ice core sediments were analyzed for elemental composition, and multistep Fe-leaching experiments were conducted to determine the fraction of soluble Fe. Thus we have ascertained the solubility of particulate Fe prior to onset of melt season. Dissolved trace metals were also analyzed to ascertain changes in concentration with ice core depth of lithogenic elements (Mn, Al) and biologically important elements (Si, Mo, Cu, Zn). Preliminary results show some enrichment of lithogenic inputs near surface, indicating dust deposition, and lower portions of the cores, suggesting resuspended sediments from the continental shelf. Concentrations of some biologically important elements decrease with depth, suggesting possible