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1

Heavy Metal.  

ERIC Educational Resources Information Center

Discusses the advantages, both functional and economic, of using a standing-seam metal roof in both new roof installations and reroofing projects of educational facilities. Structural versus non-structural standing-seam roofs are described as are the types of insulation that can be added and roof finishes used. (GR)

Shoemaker, W. Lee

1998-01-01

2

Plants absorb heavy metals  

Microsoft Academic Search

Decontamination of heavy metals-polluted soils remains one of the most intractable problems of cleanup technology. Currently available techniques include extraction of the metals by physical and chemical means, such as acid leaching and electroosmosis, or immobilization by vitrification. There are presently no techniques for cleanup which are low cost and retain soil fertility after metals removal. But a solution to

1995-01-01

3

PHYTOEXTRACTION OF HEAVY METALS  

E-print Network

of phytoextraction as a means for removing heavy metals from contaminated soils The use of plants to remove contaminants from soils Contaminants must be in harvestable portions of the plant (Wongkongkatep et al. 2003 Plants Chelating agents Pb hyperaccumulation Effects of pH on metal extraction Disposal options

Blouin-Demers, Gabriel

4

Hazards of heavy metal contamination  

Microsoft Academic Search

The main threats to human health from heavy metals are associated with exposure to lead, cadmium, mercury and arsenic. These metals have been extensively studied and their effects on human health regularly reviewed by international bodies such as the WHO. Heavy metals have been used by humans for thousands of years. Although several adverse health effects of heavy metals have

Lars Järup

2003-01-01

5

Microbial heavy-metal resistance  

Microsoft Academic Search

We are just beginning to understand the metabolism of heavy metals and to use their metabolic functions in biotechnology,\\u000a although heavy metals comprise the major part of the elements in the periodic table. Because they can form complex compounds,\\u000a some heavy metal ions are essential trace elements, but, essential or not, most heavy metals are toxic at higher concentrations.\\u000a This

D. H. Nies

1999-01-01

6

Biosorption of heavy metals  

SciTech Connect

Only within the past decade has the potential of metal biosorption by biomass materials been well established. For economic reasons, of particular interest are abundant biomass types generated as a waste byproduct of large-scale industrial fermentations or certain metal-binding algae found in large quantities in the sea. These biomass types serve as a basis for newly developed metal biosorption processes foreseen particularly as a very competitive means for the detoxification of metal-bearing industrial effluents. The assessment of the metal-building capacity of some new biosorbents is discussed. Lead and cadmium, for instance, have been effectively removed from very dilute solutions by the dried biomass of some ubiquitous species of brown marine algae such as Ascophyllum and Sargassum, which accumulate more than 30% of biomass dry weight in the metal. Mycelia of the industrial steroid-transforming fungi Rhizopus and Absidia are excellent biosorbents for lead, cadmium, copper, zinc, and uranium and also bind other heavy metals up to 25% of the biomass dry weight. Biosorption isotherm curves, derived from equilibrium batch sorption experiments, are used in the evaluation of metal uptake by different biosorbents. Further studies are focusing on the assessment of biosorbent performance in dynamic continuous-flow sorption systems. In the course of this work, new methodologies are being developed that are aimed at mathematical modeling of biosorption systems and their effective optimization. 115 refs., 7 figs., 3 tabs.

Volesky, B. [McGill Univ., Montreal (Canada)]|[B.V. Sorbex, Inc., Montreal (Canada); Holan, Z.R. [McGill Univ., Montreal (Canada)

1995-05-01

7

Plants absorb heavy metals  

SciTech Connect

Decontamination of heavy metals-polluted soils remains one of the most intractable problems of cleanup technology. Currently available techniques include extraction of the metals by physical and chemical means, such as acid leaching and electroosmosis, or immobilization by vitrification. There are presently no techniques for cleanup which are low cost and retain soil fertility after metals removal. But a solution to the problem could be on the horizon. A small but growing number of plants native to metalliferous soils are known to be capable of accumulating extremely high concentrations of metals in their aboveground portions. These hyperaccumulators, as they are called, contain up to 1,000 times larger metal concentrations in their aboveground parts than normal species. Their distribution is global, including many different families of flowering plants of varying growth forms, from herbaceous plants to trees. Hyperaccumulators absorb metals they do not need for their own nutrition. The metals are accumulated in the leaf and stem vacuoles, and to a lesser extent in the roots.

Parry, J.

1995-02-01

8

Microorganisms and heavy metal toxicity  

Microsoft Academic Search

The environmental and microbiological factors that can influence heavy metal toxicity are discussed with a view to understanding the mechanisms of microbial metal tolerance. It is apparent that metal toxicity can be heavily influenced by environmental conditions. Binding of metals to organic materials, precipitation, complexation, and ionic interactions are all important phenomena that must be considered carefully in laboratory and

Geoffrey M. Gadd; Alan J. Griffiths

1977-01-01

9

SULFIDE PRECIPITATION OF HEAVY METALS  

EPA Science Inventory

The research program was initiated with the objective of evaluating a new process, the sulfide precipitation of heavy metals from industrial wastewaters. The process was expected to effect a more complete removal of heavy metals than conventional lime processing because of the mu...

10

Heavy metals in water organisms  

Microsoft Academic Search

Chemical substances of anthropogenic origin polluting surface waters are dangerous to aquatic organisms and have varying effects on microbes, plants and animals. Living organisms frequently accumulate pollutants, signaling in this way their presence in the environment. Accumulation is particularly characteristic of heavy metals entering surface waters as industrial, agricultural and communal wastes. Heavy metals have come into the focus of

Salanki

1985-01-01

11

HEAVY METAL PUMPS IN PLANTS  

EPA Science Inventory

Plants have been proposed as a bioremediation tool to help remove toxic heavy metals from contaminated land and water. However, little is known about how plants take up heavy metals from the soil and transport them to different parts of the plant. An important long term goal is t...

12

STANDARD OPERATING PROCEDURE HEAVY METAL SALTS (selected)  

E-print Network

12.1 STANDARD OPERATING PROCEDURE for HEAVY METAL SALTS (selected) Location(s): ___________________________________________________ Chemical(s): heavy metal salts: acetates, chlorides, sulfates, nitrates, anhydrides, oxides, hydroxides procedures. Specific instructions: All solids and liquids containing heavy metals must be disposed

Pawlowski, Wojtek

13

Biosorption of heavy metals  

Microsoft Academic Search

Only within the past decade has the potential of metal biosorption by biomass materials been well established. For economic reasons, of particular interest are abundant biomass types generated as a waste byproduct of large-scale industrial fermentations or certain metal-binding algae found in large quantities in the sea. These biomass types serve as a basis for newly developed metal biosorption processes

B. Volesky; Z. R. Holant

1995-01-01

14

OXFORD BIBLIOGRAPHIES IN ECOLOGY "HEAVY METAL TOLERANCE"  

E-print Network

OXFORD BIBLIOGRAPHIES IN ECOLOGY "HEAVY METAL TOLERANCE" By Nishanta Rajakaruna and Robert S. BoydBibliographies@oup.com. #12;Introduction General Overviews Journals Defining Heavy Metal Tolerance Physiological Mechanisms and Restoration Phytoextraction of Heavy Metals Genetic Engineering for Metal Tolerance Model Organisms

Rajakaruna, Nishanta

15

Process for removing heavy metal compounds from heavy crude oil  

DOEpatents

A process is provided for removing heavy metal compounds from heavy crude oil by mixing the heavy crude oil with tar sand; preheating the mixture to a temperature of about 650.degree. F.; heating said mixture to up to 800.degree. F.; and separating tar sand from the light oils formed during said heating. The heavy metals removed from the heavy oils can be recovered from the spent sand for other uses.

Cha, Chang Y. (Golden, CO); Boysen, John E. (Laramie, WY); Branthaver, Jan F. (Laramie, WY)

1991-01-01

16

Heavy Metal Stars  

NASA Astrophysics Data System (ADS)

La Silla Telescope Detects Lots of Lead in Three Distant Binaries Summary Very high abundances of the heavy element Lead have been discovered in three distant stars in the Milky Way Galaxy . This finding strongly supports the long-held view that roughly half of the stable elements heavier than Iron are produced in common stars during a phase towards the end of their life when they burn their Helium - the other half results from supernova explosions. All the Lead contained in each of the three stars weighs about as much as our Moon. The observations show that these "Lead stars" - all members of binary stellar systems - have been more enriched with Lead than with any other chemical element heavier than Iron. This new result is in excellent agreement with predictions by current stellar models about the build-up of heavy elements in stellar interiors. The new observations are reported by a team of Belgian and French astronomers [1] who used the Coude Echelle Spectrometer on the ESO 3.6-m telescope at the La Silla Observatory (Chile). PR Photo 26a/01 : A photo of HD 196944 , one of the "Lead stars". PR Photo 26b/01 : A CES spectrum of HD 196944 . The build-up of heavy elements Astronomers and physicists denote the build-up of heavier elements from lighter ones as " nucleosynthesis ". Only the very lightest elements (Hydrogen, Helium and Lithium [2]) were created at the time of the Big Bang and therefore present in the early universe. All the other heavier elements we now see around us were produced at a later time by nucleosynthesis inside stars. In those "element factories", nuclei of the lighter elements are smashed together whereby they become the nuclei of heavier ones - this process is known as nuclear fusion . In our Sun and similar stars, Hydrogen is being fused into Helium. At some stage, Helium is fused into Carbon, then Oxygen, etc. The fusion process requires positively charged nuclei to move very close to each other before they can unite. But with increasing atomic mass and hence, increasing positive charge of the nuclei, the electric repulsion between the nuclei becomes stronger and stronger. In fact, the fusion process only works up to a certain mass limit, corresponding to the element Iron [2]. All elements that are heavier than Iron cannot be produced via this path. But then, how were those heavy elements we now find on the Earth produced in the first place? From where comes the Zirconium in artificial diamonds, the Barium that colours fireworks, the Tungsten in the filaments in electric bulbs? Which process made the Lead in your car battery? Beyond iron The production of elements heavier than Iron takes place by adding neutrons to the atomic nuclei . These neutral particles do not feel any electrical repulsion from the charged nuclei. They can therefore easily approach them and thereby create heavier nuclei. This is indeed the way the heaviest chemical elements are built up. There are actually two different stellar environments where this process of "neutron capture" can happen. One place where this process occurs is inside very massive stars when they explode as supernovae . In such a dramatic event, the build-up proceeds very rapidly, via the so-called "r-process" ( "r" for rapid ). The AGB stars But not all heavy elements are created in such an explosive way. A second possibility follows a more "peaceful" road. It takes place in rather normal stars, when they burn their Helium towards the end of their lives. In the so-called "s-process" ( "s" for slow ), heavier elements are then produced by a rather gentle addition of neutral neutrons to atomic nuclei. In fact, roughly half of all the elements heavier than Iron are believed to be synthesized by this process during the late evolutionary phases of stars. This process takes place during a specific stage of stellar evolution, known as the "AGB" phase [3]. It occurs just before an old star expels its gaseous envelope into the surrounding interstellar s

2001-08-01

17

Heavy Metals Precipitation in Sewage Sludge  

Microsoft Academic Search

There is a great need for heavy metal removal from strongly metal?polluted sewage sludges. One of the advantages of heavy metal removal from this type of sludge is the possibility of the sludge disposal to landfill with reduced risk of metals being leached to the surface and groundwater. Another advantage is the application of the sludge as soil improver. The

Marina Maya Marchioretto; Harry Bruning; Wim Rulkens

2005-01-01

18

Heavy metal pollution of urban soils  

NASA Astrophysics Data System (ADS)

The chemical properties of urban soils (southeastern administrative district, Moscow) affecting the behavior of heavy metals were studied. The current heavy metal pollution level of the soils was assessed. The use of different approaches for the pollution standardization is shown to produce different results. The fractional composition of the metal compounds in the soils and the factors affecting its formation under technogenic pollution were investigated. In the district studied, the distribution of heavy metals by the fractions primarily depended on the chemical properties of the heavy metals themselves; the pollution level; and, to a lesser degree, on the soil properties. Zinc and cadmium were the most mobile metals in the soils studied.

Plyaskina, O. V.; Ladonin, D. V.

2009-07-01

19

The Heavy Metal Subculture and Suicide.  

ERIC Educational Resources Information Center

Assessed relationship between heavy metal music and suicide with data on heavy metal magazine subscriptions and youth suicide in 50 states. Found that, controlling for other predictors of suicide, greater strength of metal subculture, higher youth suicide rate, suggests that music perhaps nurtures suicidal tendencies already present in subculture.…

Stack, Steven; And Others

1994-01-01

20

Industrial hygiene of selected heavy metals  

SciTech Connect

The industrial hygiene of heavy metals consists of recognition, evaluation, and control of exposures in the occupational environment. Several of these metals have been in use since ancient times. Reports of health effects and poisonings from overexposures also have a long history. This report discusses the industrial hygiene of the heavy metals, lead, cadmium, mercury, and manganese.

Woodring, J.L.

1993-08-01

21

Heavy metals in plants and phytoremediation  

Microsoft Academic Search

Goal, Scope and Background  In some cases, soil, water and food are heavily polluted by heavy metals in China. To use plants to remediate heavy metal\\u000a pollution would be an effective technique in pollution control. The accumulation of heavy metals in plants and die role of\\u000a plants in removing pollutants should be understood in order to implement phytoremediation, which makes use

Shuiping Cheng

2003-01-01

22

Heavy metals in Antarctic organisms  

SciTech Connect

To evaluate levels of essential (zinc and copper) and non-essential (mercury and cadmium) heavy metals, 34 species of organisms from different areas close to the Antarctic Peninsula were analysed. These included algae, filter-feeders, omnivorous invertebrates and vertebrates. Mercury was not detected, while cadmium was found in the majority of organisms analysed (detection limit was 0.05 ppm for both metals). The highest cadmium concentration was observed in the starfish Odontaster validus. Anthozoans, sipunculids and nudibranchs showed maximum levels of zinc, while the highest copper level was found in the gastropod Trophon brevispira. Mercury and cadmium levels in fishes were below the detection limit. Concentrations of essential and non-essential metals in birds were highest in liver followed by muscle and eggs. Cadmium and mercury levels in muscle of southern elephant seals were above the detection limit, whereas in Antarctic fur seals they were below it. The objective of the study was to gather baseline information for metals in Antarctic Ocean biota that may be needed to detect, measure and monitor future environmental changes. 46 refs., 7 figs., 8 tabs.

Moreno, J.E.A. de; Moreno, V.J. [Universidad Nacional de Mar del Plata (Argentina); Gerpe, M.S.; Vodopivez, C. [Instituto Antartico Argentino, Buenos Aires (Argentina)

1997-02-01

23

Bioremoval of heavy metals by bacterial biomass.  

PubMed

Heavy metals are among the most common pollutants found in the environment. Health problems due to the heavy metal pollution become a major concern throughout the world, and therefore, various treatment technologies such as reverse osmosis, ion exchange, solvent extraction, chemical precipitation, and adsorption are adopted to reduce or eliminate their concentration in the environment. Biosorption is a cost-effective and environmental friendly technique, and it can be used for detoxification of heavy metals in industrial effluents as an alternative treatment technology. Biosorption characteristics of various bacterial species are reviewed here with respect to the results reported so far. The role of physical, chemical, and biological modification of bacterial cells for heavy metal removal is presented. The paper evaluates the different kinetic, equilibrium, and thermodynamic models used in bacterial sorption of heavy metals. Biomass characterization and sorption mechanisms as well as elution of metal ions and regeneration of biomass are also discussed. PMID:25471624

Aryal, Mahendra; Liakopoulou-Kyriakides, Maria

2015-01-01

24

Inhibition of photosynthesis by heavy metals  

Microsoft Academic Search

Inhibition of photosynthesis by heavy metals is well documented. In this review the results are compared between in vitro experiments on isolated systems (chloroplasts, enzymes ­.), experiments on excised leaves and intact plants and algae in vivo. In vitro experiments suggest potential sites of heavy metal interaction with photosynthesis at several levels of organisation, which are not necessarily confirmed in

H. Clijsters; F. Assche

1985-01-01

25

Heavy Metal, Religiosity, and Suicide Acceptability.  

ERIC Educational Resources Information Center

Reports on data taken from the General Social Survey that found a link between "heavy metal" rock fanship and suicide acceptability. Finds that relationship becomes nonsignificant once level of religiosity is controlled. Heavy metal fans are low in religiosity, which contributes to greater suicide acceptability. (Author/JDM)

Stack, Steven

1998-01-01

26

Heavy Metal Music and Adolescent Suicidal Risk.  

ERIC Educational Resources Information Center

Studied differentiating characteristics of youth who prefer heavy metal music, worship music, and use music for vicarious release. Data for 275 secondary school students suggest that heavy metal music preference and worshipping is not related to suicidal risk when controlling for other suicide factors. Discusses findings in the context of…

Lacourse, Eric; Claes, Michel; Villeneuve, Martine

2001-01-01

27

Community Heavy Metal Exposure, San Francisco, California  

Microsoft Academic Search

Heavy metals are natural elements that generally occur in minute concentrations in the earth's crust. While some of these elements, in small quantities, are vital to life, most are harmful in larger doses. Various industrial and agricultural processes can result in dangerously high concentrations of heavy metals in our environment. Consequently, humans can be exposed to unsafe levels of these

A. Chavez; M. Devine; T. Ho; I. Zapata; M. Bissell; J. Neiss

2008-01-01

28

Effect of heavy metals on soil fungi  

NASA Astrophysics Data System (ADS)

Fungi constitute a high proportion of the microbial biomass in soil.Being widespread in soil their large surface-to-volume ratio and high metabolic activity, fungi can contribute significantly to heavy metal dynamics in soil. At neutral pH heavy metals in soils tend to be immobilized to precipitation and/or absorption to cation exchange sites of clay minerals. In the acidic soils, metals are more mobile and enter food webs easier. Microbial production of acids and chelating agents can mobilize to toxic metals. Mobilization is often by uptake and intracellular accumulation of the heavy metlas, and in this way, the bioavailability of metals towards other organisms can be more reduced. Fungi were isolated from soils from Upper Silesia in Poland and belonged to widespread genera: Aspergillus, Cladosporium, Penicillium and Trichoderma. Fungi from different taxonomic groups differ greatly in their tolerance to heavy metals. This could be related to their wall structure and chemistry as well as biochemical and physiological characteristics of fungi. Localization of metals in fungal cells was studied using electron microscopy analysis. Metal biosorption in the cell wall can be complex as melanin granules. Fungal vacuoles have an important role in the regulation of the cytosolic concentration of metal ions, and may contribute to heavy metal tolerance.In polluted soils with heavy metals, fungal species composition can be changed and their physiological activity can be changed, too.

Sosak-?widerska, Bo?ena

2010-05-01

29

Heavy metal pollution of urban soils  

Microsoft Academic Search

The chemical properties of urban soils (southeastern administrative district, Moscow) affecting the behavior of heavy metals\\u000a were studied. The current heavy metal pollution level of the soils was assessed. The use of different approaches for the pollution\\u000a standardization is shown to produce different results. The fractional composition of the metal compounds in the soils and\\u000a the factors affecting its formation

O. V. Plyaskina; D. V. Ladonin

2009-01-01

30

EDTA enhanced heavy metal phytoextraction: metal accumulation, leaching and toxicity  

Microsoft Academic Search

Synthetic chelates such as ethylene diamine tetraacetic acid (EDTA) have been shown to enhance phytoextraction of some heavy metals from contaminated soil. In a soil column study, we examined the effect of EDTA on the uptake of Pb, Zn and Cd by Chinese cabbage (Brassica rapa), mobilization and leaching of heavy metals and the toxicity effects of EDTA additions on

H. Gr?man; Š. Velikonja-Bolta; D. Vodnik; B. Kos; D. Leštan

2001-01-01

31

Heavy Metals Removal by Biosorption and Flotation  

Microsoft Academic Search

The removal of a mixture of heavy (toxic) metal cations (copper, nickeland zinc) from liquid effluents was investigated in this study at pilotscale, using counter-current contact mode. The innovative processinvolved the abstraction of metal ions onto fungal biosorbents, followedby the application of flotation for the subsequent solid\\/liquid separationof biomass particles. The ability of microorganisms to remove metal ionsfrom aqueous solutions

K. A. Matis; A. I. Zouboulis; N. K. Lazaridis

2003-01-01

32

Removal of heavy metals from waste streams  

SciTech Connect

A method for removing heavy metals from effluent water is described comprising performing sequentially the following steps: (a) adding from 7-333 ppm of an anionic surfactant to the effluent water to provide coagulatable heavy metal ion; (b) adjusting the effluent water pH to within the range of 8 to 10, (c) providing from 10-200 ppm of a cationic coagulant to coagulate the heavy metal ion, (d) providing from 0.3 to 5.0 ppm of a polymeric flocculant whereby a heavy metal containing floc is formed for removal from the effluent water, and, (e) then removing the floc from the effluent water, wherein the anionic surfactant is sodium lauryl ether sulfate. The cationic coagulant is selected from the group consisting of diallyl dimethylammonium chloride polymer, epichlorohydrin dimethylamine polymer, ethylene amine polymer, polyaluminum chloride, and alum; and the flocculant is an acrylamide/sodium acrylate copolymer having an RSV greater than 23.

Spence, M.D.; Kozaruk, J.M.; Melvin, M.; Gardocki, S.M.

1988-07-19

33

Heavy metal contamination from geothermal sources.  

PubMed Central

Liquid-dominated hydrothermal reservoirs, which contain saline fluids at high temperatures and pressures, have a significant potential for contamination of the environment by heavy metals. The design of the power conversion cycle in a liquid-dominated geothermal plant is a key factor in determining the impact of the installation. Reinjection of the fluid into the reservoir minimizes heavy metal effluents but is routinely practiced at few installations. Binary power cycles with reinjection would provide even cleaner systems but are not yet ready for commercial application. Vapor-dominated systems, which contain superheated steam, have less potential for contamination but are relatively uncommon. Field data on heavy metal effluents from geothermal plants are sparse and confounded by contributions from "natural" sources such as geysers and hot springs which often exist nearby. Insofar as geothermal power supplies are destined to multiply, much work is required on their environmental effects including those caused by heavy metals. PMID:1227849

Sabadell, J E; Axtmann, R C

1975-01-01

34

DECONTAMINATION OF HEAVY METALS WITH BACTERIA  

EPA Science Inventory

OBJECTIVES: To discover, improve, understand the mechanisms and use naturally occurring bacteria to decontiminate in situ heavy metals from the soils, sediments and waters to protect human health and the environment. ABSTRACT: Our laboratory (Vesper et al. ...

35

Heavy metal contamination from geothermal sources.  

PubMed

Liquid-dominated hydrothermal reservoirs, which contain saline fluids at high temperatures and pressures, have a significant potential for contamination of the environment by heavy metals. The design of the power conversion cycle in a liquid-dominated geothermal plant is a key factor in determining the impact of the installation. Reinjection of the fluid into the reservoir minimizes heavy metal effluents but is routinely practiced at few installations. Binary power cycles with reinjection would provide even cleaner systems but are not yet ready for commercial application. Vapor-dominated systems, which contain superheated steam, have less potential for contamination but are relatively uncommon. Field data on heavy metal effluents from geothermal plants are sparse and confounded by contributions from "natural" sources such as geysers and hot springs which often exist nearby. Insofar as geothermal power supplies are destined to multiply, much work is required on their environmental effects including those caused by heavy metals. PMID:1227849

Sabadell, J E; Axtmann, R C

1975-12-01

36

Heavy metals and living systems: An overview  

PubMed Central

Heavy metals are natural constituents of the earth's crust, but indiscriminate human activities have drastically altered their geochemical cycles and biochemical balance. This results in accumulation of metals in plant parts having secondary metabolites, which is responsible for a particular pharmacological activity. Prolonged exposure to heavy metals such as cadmium, copper, lead, nickel, and zinc can cause deleterious health effects in humans. Molecular understanding of plant metal accumulation has numerous biotechnological implications also, the long term effects of which might not be yet known. PMID:21713085

Singh, Reena; Gautam, Neetu; Mishra, Anurag; Gupta, Rajiv

2011-01-01

37

Heavy metal removal and recovery using microorganisms  

SciTech Connect

Microorganisms -- bacteria, fungi, and microalgae -- can accumulate relatively large amounts of toxic heavy metals and radionuclides from the environment. These organisms often exhibit specificity for particular metals. The metal content of microbial biomass can be a substantial fraction of total dry weight with concentration factors (metal in dry biomass to metal in solution) exceeding one million in some cases. Both living and inert (dead) microbial biomass can be used to reduce heavy metal concentrations in contaminated waters to very low levels -- parts per billion and even lower. In many respects (e.g. specificity, residual metal concentrations, accumulation factors, and economics) microbial bioremoval processes can be superior to conventional processes, such as ion exchange and caustic (lime or hydroxide) precipitation for heavy metals removal from waste and contaminated waters. Thus, bioremoval could be developed to contribute to the clean-up of wastes at the Savannah River Site (SRS) and other DOE facilities. However, the potential advantages of bioremoval processes must still be developed into practical operating systems. A detailed review of the literature suggests that appropriate bioremoval processes could be developed for the SRS. There is great variability from one biomass source to another in bioremoval capabilities. Bioremoval is affected by pH, other ions, temperature, and many other factors. The biological (living vs. dead) and physical (immobilized vs. dispersed) characteristics of the biomass also greatly affect metal binding. Even subtle differences in the microbial biomass, such as the conditions under which it was cultivated, can have major effects on heavy metal binding.

Wilde, E.W. (Westinghouse Savannah River Co., Aiken, SC (United States)); Benemann, J.R. (Benemann (J.R.), Pinole, CA (United States))

1991-02-01

38

Detection of Heavy Metal Ions Based on Quantum Point Contacts  

E-print Network

Detection of Heavy Metal Ions Based on Quantum Point Contacts Vasanth Rajagopalan, Salah Boussaad. The ability to detect trace amounts of metal ions is important because of the toxicity of heavy metal ions on many living organisms and the consequence of heavy metal ions not being biodegradable. To date, heavy

Zhang, Yanchao

39

Heavy Metal Risk Management: Case Analysis  

PubMed Central

To prepare measures for practical policy utilization and the control of heavy metals, hazard control related institutions by country, present states of control by country, and present states of control by heavy metals were examined. Hazard control cases by heavy metals in various countries were compared and analyzed. In certain countries (e.g., the U.S., the U.K., and Japan), hazardous substances found in foods (e.g., arsenic, lead, cadmium, and mercury) are controlled. In addition, the Joint FAO/WHO Expert Committee on Food Additives (JECFA) recommends calculating the provisional tolerable weekly intake (PTWI) of individual heavy metals instead of the acceptable daily intake (ADI) to compare their pollution levels considering their toxicity accumulated in the human body. In Korea, exposure assessments have been conducted, and in other countries, hazardous substances are controlled by various governing bodies. As such, in Korea and other countries, diverse food heavy metal monitoring and human body exposure assessments are conducted, and reducing measures are prepared accordingly. To reduce the danger of hazardous substances, many countries provide leaflets and guidelines, develop hazardous heavy metal intake recommendations, and take necessary actions. Hazard control case analyses can assist in securing consumer safety by establishing systematic and reliable hazard control methods. PMID:24278603

Kim, Ji Ae; Lee, Seung Ha; Choi, Seung Hyun; Jung, Ki Kyung; Park, Mi Sun; Jeong, Ji Yoon; Hwang, Myung Sil; Yoon, Hae Jung; Choi, Dal Woong

2012-01-01

40

Selective Separation of Heavy Metals from Industrial Wastewater Streams by Means of Heavy Metal Bonding Agents  

Microsoft Academic Search

Industrial wastewater is often contaminated with heavy metals and must undergo expensive and elaborate treatment. A new, environmentally\\u000a friendly process, which allows both metals and water to be reused, has been developed. It comprises the following three process\\u000a stages: firstly, a metal bonding agent (BA) is added to the wastewater to bind the heavy metal; secondly, the loaded BA is

V. Mavrov; T. Erwe; H. Chmiel

2004-01-01

41

Histochemical demonstration of heavy metals  

Microsoft Academic Search

The three steps of the sulphide silver method have been examined: 1) Transformation of metals to metal sulphides; 2) Fixation and embedding or freezing of the tissue for sectioning; and 3) Deposition of metallic silver on the metal sulphides in a physical developer. Based on the results, a revised method is described and discussed. It is particularly important 1) To

G. Danscher

1981-01-01

42

Gold Nanoparticle-Based Sensing of "Spectroscopically Silent" Heavy Metal  

E-print Network

Letters Gold Nanoparticle-Based Sensing of "Spectroscopically Silent" Heavy Metal Ions Youngjin Kim of aqueous heavy metal ions, including toxic metals such as lead, cadmium, and mercury, is described that by functionalizing metal nanoparticles with appropriate heavy-metal ion receptors, the particles might be coaxed

43

ANALYSIS OF HEAVY METALS IN STORMWATER  

EPA Science Inventory

Stormwater sampling for colloidal and dissolved metals and organic carbon has been initiated at six outfalls draining locally-designated, nonindustrial land uses in Monmouth County, NJ. Of the heavy metals, only Cu and Zn were found in all samples, mostly in dissolved form. Large...

44

Heavy metals in tropical Lake Kariba, Zimbabwe  

Microsoft Academic Search

Metal mining is carried out in the drainage basin of Lake Kariba, Zimbabwe. In an attempt to assess the distribution of heavy metals in the lake ecosystem, the concentrations of chromium (Cr), cadmium (Cd), copper (Cu), lead (Pb), manganese (Mn), nickel (Ni), zinc (Zn), and selenium (Se) were analysed in the following ecosystem components at different locations in the lake;

Håkan Berg; Martina Kiibus; Nils Kautsky

1995-01-01

45

Advances in the biosorption of heavy metals  

Microsoft Academic Search

The biosorption of heavy metals by certain types of non-living biomass is a highly cost-effective new alternative for the decontamination of metal-containing effluents. Our understanding of the mechanisms of metal biosorption now allows the process to be scaled up and used in field applications, with packed-bed sorption columns being perhaps the most efficient for this purpose. Regenerating the biosorbents increases

David Kratochvil; Bohumil Volesky

1998-01-01

46

Heavy metal monitoring in sea turtles using eggs  

Microsoft Academic Search

Heavy metals in the muscles, livers, kidneys and eggs of loggerhead turtles and green sea turtles were analysed to develop a non-killing method of heavy metal monitoring using eggs. Heavy metal concentrations were higher in the liver and kidney than in the muscle and eggs of loggerhead turtles. Within an egg, yolk contained the highest concentrations and burdens of heavy

Haruya Sakai; Hideki Ichihashi; Hiroyuki Suganuma; Ryo Tatsukawa

1995-01-01

47

Heavy metal contaminants in yerberia shop products.  

PubMed

Complementary and alternative medications, including the use of herbal medications, have become quite popular in the USA. Yerberias are found throughout the southwest and specialize in selling Hispanic herbal products. The products sold in these stores are not regulated by any governmental agency. Previous reports have found Ayurvedic medications contain high levels of lead, mercury, and arsenic. The primary purpose of this study is to examine the prevalence of heavy metal contaminants sold at Yerberia stores in the southwest. Yerberias in the Phoenix, Arizona area were identified via search of an on-line search engine using the words "Yerberia Phoenix." Every second store was selected, and products were purchased using a standard script. The products were subsequently analyzed for mercury, lead, and arsenic. The main outcome is the prevalence of heavy metal content in over-the-counter "cold" medications purchased at a Yerberia. Twenty-two samples were purchased. One product contained pure camphor (2-camphone) and was subsequently not further analyzed. Of the 21 samples analyzed, lead was found in 4/21 (19.4 %). Arsenic and mercury were in 1/21 (4.8 %) each. Because two samples contained two heavy metals, the total prevalence of heavy metals was 4/21 (19.4). Heavy metal contaminants are commonly encountered in over-the-counter herbal "cold" medications purchased at Yerberias in the southwest. PMID:22562238

Levine, Michael; Mihalic, Jason; Ruha, Anne-Michelle; French, Robert N E; Brooks, Daniel E

2013-03-01

48

Heavy Metal Poisoning and Cardiovascular Disease  

PubMed Central

Cardiovascular disease (CVD) is an increasing world health problem. Traditional risk factors fail to account for all deaths from CVD. It is mainly the environmental, dietary and lifestyle behavioral factors that are the control keys in the progress of this disease. The potential association between chronic heavy metal exposure, like arsenic, lead, cadmium, mercury, and CVD has been less well defined. The mechanism through which heavy metals act to increase cardiovascular risk factors may act still remains unknown, although impaired antioxidants metabolism and oxidative stress may play a role. However, the exact mechanism of CVD induced by heavy metals deserves further investigation either through animal experiments or through molecular and cellular studies. Furthermore, large-scale prospective studies with follow up on general populations using appropriate biomarkers and cardiovascular endpoints might be recommended to identify the factors that predispose to heavy metals toxicity in CVD. In this review, we will give a brief summary of heavy metals homeostasis, followed by a description of the available evidence for their link with CVD and the proposed mechanisms of action by which their toxic effects might be explained. Finally, suspected interactions between genetic, nutritional and environmental factors are discussed. PMID:21912545

Alissa, Eman M.; Ferns, Gordon A.

2011-01-01

49

Community Heavy Metal Exposure, San Francisco, California  

NASA Astrophysics Data System (ADS)

Heavy metals are natural elements that generally occur in minute concentrations in the earth's crust. While some of these elements, in small quantities, are vital to life, most are harmful in larger doses. Various industrial and agricultural processes can result in dangerously high concentrations of heavy metals in our environment. Consequently, humans can be exposed to unsafe levels of these elements via the air we breathe, the water and food we consume, and the many products we use. During a two week study we collected numerous samples of sediments, water, food, and household items from around the San Francisco Bay Area that represent industrial, agricultural, and urban/residential settings. We analyzed these samples for Mercury (Hg), Lead (Pb), and Arsenic (As). Our goal was to examine the extent of our exposure to heavy metals in our daily lives. We discovered that many of the common foods and materials in our lives have become contaminated with unhealthy concentrations of these metals. Of our food samples, many exceeded the EPA's Maximum Contaminant Levels (MCL) set for each metal. Meats (fish, chicken, and beef) had higher amounts of each metal than did non-meat items. Heavy metals were also prevalent in varying concentrations in the environment. While many of our samples exceeded the EPA's Sediment Screening Level (SSL) for As, only two other samples surpassed the SSL set for Pb, and zero of our samples exceeded the SSL for Hg. Because of the serious health effects that can result from over-exposure to heavy metals, the information obtained in this study should be used to influence our future dietary and recreational habits.

Chavez, A.; Devine, M.; Ho, T.; Zapata, I.; Bissell, M.; Neiss, J.

2008-12-01

50

Extractable heavy metals in Atlantic coast soils  

SciTech Connect

The analysis of soils, using 0.1 N HCl as an extractant for the heavy metals, Cd, Cr, Ni and Pb on fine textured North Shore and coarse textured Annapolis Valley soils was completed. Results show ranges of 0.012 to 0.469 ppM Cd, 0.102 to 2.90 ppM Cr, 0.16 to 29.25 ppM Ni, and 0.12 to 244.8 ppM Pb. Correlation studies indicate that the heavy metal content of fine textured soils is less influenced by changes in clay content and organic matter than are coarse textured soils. Generally the surface layers (0 to 15 cms) are higher in extractable heavy metal content than the lower layers (15 to 30 cms).

MacLean, K.S.; Langille, W.M.

1980-01-01

51

Transfer of heavy metals through terrestrial food webs: a review.  

PubMed

Heavy metals are released into the environment by both anthropogenic and natural sources. Highly reactive and often toxic at low concentrations, they may enter soils and groundwater, bioaccumulate in food webs, and adversely affect biota. Heavy metals also may remain in the environment for years, posing long-term risks to life well after point sources of heavy metal pollution have been removed. In this review, we compile studies of the community-level effects of heavy metal pollution, including heavy metal transfer from soils to plants, microbes, invertebrates, and to both small and large mammals (including humans). Many factors contribute to heavy metal accumulation in animals including behavior, physiology, and diet. Biotic effects of heavy metals are often quite different for essential and non-essential heavy metals, and vary depending on the specific metal involved. They also differ for adapted organisms, including metallophyte plants and heavy metal-tolerant insects, which occur in naturally high-metal habitats (such as serpentine soils) and have adaptations that allow them to tolerate exposure to relatively high concentrations of some heavy metals. Some metallophyte plants are hyperaccumulators of certain heavy metals and new technologies using them to clean metal-contaminated soil (phytoextraction) may offer economically attractive solutions to some metal pollution challenges. These new technologies provide incentive to catalog and protect the unique biodiversity of habitats that have naturally high levels of heavy metals. PMID:25800370

Gall, Jillian E; Boyd, Robert S; Rajakaruna, Nishanta

2015-04-01

52

Heavy metal displacement in chelate-irrigated soil during phytoremediation  

Microsoft Academic Search

Heavy metals in wastewater sewage sludge (biosolids), applied to land, contaminate soils. Phytoremediation, the use of plants to clean up toxic heavy metals, might remove them. Chelating agents are added to soil to solubilize the metals for enhanced phytoextraction. Yet no studies follow the displacement and leaching of heavy metals in soil with and without roots following solubilization with chelates.

M. S Liphadzi; M. B Kirkham

2003-01-01

53

Engineering TCE-Degrading Rhizobacteria for Heavy Metal  

E-print Network

Engineering TCE-Degrading Rhizobacteria for Heavy Metal Accumulation and Enhanced TCE Degradation are currently co-contami- nated with organic pollutants such as trichloroethene (TCE) and heavy metals that will survive and thrive in soil heavily polluted with heavy metals. In this work, a gene coding for the metal

Chen, Wilfred

54

Phytoremediation of heavy metals by Eichhornia crassipes  

Microsoft Academic Search

Eichhornia crassipes was tested for its ability to bioconcentrate 8 toxic metals (Ag, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) commonly found in wastewater\\u000a from industries. Young plants of equal size were grown hydroponically and amended with 0, 0.1, 0.3, 0.5, 1.0, 3.0, and 5.0\\u000a mM of each heavy metal individually for 21 days. The test plant had the lowest

Victor J. Odjegba; Ishola O. Fasidi

2007-01-01

55

ANALYSIS OF HEAVY METALS IN STORMWATER  

EPA Science Inventory

Sampling has been undertaken to determine the concentrations of heavy metals, both particle-associated and dissolved, in stormwater from several storm sewer outfalls in Monmouth County, NJ. This project is ongoing in concert with coordinated studies of pathogen and nutrient input...

56

Heavy metal transporters in Hemiascomycete yeasts.  

PubMed

We have compiled all known heavy metal transporters of the yeast Saccharomyces cerevisiae and identified their orthologs in four other species spanning the entire Hemiascomycete phylum. The 213 transporters belong to 27 distinct phylogenetic families distributed within the three classes: channels, secondary porters (permeases) and transport ATPases. They are present in all cellular membranes: plasma membranes, vacuoles, mitochondria, endoplasmic reticulum, nucleus, Golgi and various cytoplasmic vesicles. The major physiological heavy metals transported are: iron, manganese, zinc, copper, arsenite and cadmium. The major subfamilies that comprise the highest number of transporters are Siderophore-Iron Transporters (SIT) and CT2 (conjugated ABC transporters). They transport heavy metals (iron or cadmium, respectively) conjugated to organic chelators such as siderophores or glutathione. Both subfamilies are considerably amplified in the yeast Yarrowia lipolytica. The pattern of expansion and restriction of the subfamilies during the evolution of the different species is highly variable. The phylogenetic trees of the major transporters subfamilies distinguish homogenous clusters of transporters suggesting that possible different physiological or mechanistic functions evolved independently. We also validated the use of the Hemiascomycetes heavy metal transporters for identification of orthologs transporters in the pathogenic Basidiomycetes Cryptococcus neoformans. PMID:17011109

Diffels, J F; Seret, M-L; Goffeau, A; Baret, P V

2006-11-01

57

Heavy metal transporters in Hemiascomycete yeasts  

Microsoft Academic Search

We have compiled all known heavy metal transporters of the yeast Saccharomyces cerevisiae and identified their orthologs in four other species spanning the entire Hemiascomycete phylum. The 213 transporters belong to 27 distinct phylogenetic families distributed within the three classes: channels, secondary porters (permeases) and transport ATPases. They are present in all cellular membranes: plasma membranes, vacuoles, mitochondria, endoplasmic reticulum,

J. F. Diffels; M.-L. Seret; A. Goffeau; P. V. Baret

2006-01-01

58

Heavy Metals and Related Trace Elements.  

ERIC Educational Resources Information Center

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)

Leland, Harry V.; And Others

1978-01-01

59

Heavy metal biosorption sites in Aspergillus niger  

Microsoft Academic Search

Aspergillus niger is capable of removing heavy metals such as lead, cadmium and copper from aqueous solutions. The role played by various functional groups in the cell wall of A. niger in biosorption of lead, cadmium and copper was investigated. The biomass was subjected to chemical treatments to modify the functional groups, carboxyl, amino and phosphate, to study their role

Anoop Kapoor; T. Viraraghavan

1997-01-01

60

REMOVAL OF HEAVY METALS BY ARTIFICIAL WETLANDS  

EPA Science Inventory

Artificial wetlands have been operated successfully for treatment of municipal wastewater for a number of years at several locations in this country. However, the capability of these systems to treat heavy metal laden municipal wastewater had not previously been investigated. The...

61

Bacterial sorption of heavy metals.  

PubMed Central

Four bacteria, Bacillus cereus, B. subtilis, Escherichia coli, and Pseudomonas aeruginosa, were examined for the ability to remove Ag+, Cd2+, Cu2+, and La3+ from solution by batch equilibration methods. Cd and Cu sorption over the concentration range 0.001 to 1 mM was described by Freundlich isotherms. At 1 mM concentrations of both Cd2+ and Cu2+, P. aeruginosa and B. cereus were the most and least efficient at metal removal, respectively. Freundlich K constants indicated that E. coli was most efficient at Cd2+ removal and B. subtilis removed the most Cu2+. Removal of Ag+ from solution by bacteria was very efficient; an average of 89% of the total Ag+ was removed from the 1 mM solution, while only 12, 29, and 27% of the total Cd2+, Cu2+, and La3+, respectively, were sorbed from 1 mM solutions. Electron microscopy indicated that La3+ accumulated at the cell surface as needlelike, crystalline precipitates. Silver precipitated as discrete colloidal aggregates at the cell surface and occasionally in the cytoplasm. Neither Cd2+ nor Cu2+ provided enough electron scattering to identify the location of sorption. The affinity series for bacterial removal of these metals decreased in the order Ag greater than La greater than Cu greater than Cd. The results indicate that bacterial cells are capable of binding large quantities of different metals. Adsorption equations may be useful for describing bacterium-metal interactions with metals such as Cd and Cu; however, this approach may not be adequate when precipitation of metals occurs. Images PMID:2515800

Mullen, M D; Wolf, D C; Ferris, F G; Beveridge, T J; Flemming, C A; Bailey, G W

1989-01-01

62

Heavy metal tolerance in metal hyperaccumulator plant, Salvinia natans.  

PubMed

Metal tolerance capacity of Salvinia natans, a metal hyperaccumulator, was evaluated. Plants were exposed to 10, 30 and 50 mg L?¹ of Zn, Cd, Co, Cr, Fe, Cu, Pb, and Ni. Plant biomass, photosynthetic efficiency, quantum yield, photochemical quenching, electron transport rate and elemental (%C, H and N) constitution remained unaffected in Salvinia exposed to 30 mg L?¹ of heavy metals, except for Cu and Zn exposed plants, where significant reductions were noted in some of the measured parameters. However, a significant decline was noted in most of the measured parameters in plants exposed to 50 mg L?¹ of metal concentration. Results suggest that Salvinia has fairly high levels of tolerance to all the metals tested, but the level of tolerance varied from metal to metal. PMID:23553503

Dhir, B; Srivastava, S

2013-06-01

63

Heavy metals in the environment  

SciTech Connect

Concentration (Cd, Pb, Zn, and Cu) in soil and wildlife at the Palmerton zinc smelter site in eastern Pennsylvania were determined 6 yr after zinc smelting was terminated in 1980. Levels of the four metals were higher in litter (01 and 02 horizon) than in soil (A1 horizon), and the metals were at or near levels when the smelters were still in operation. Levels of metals in sod weft highest at sites close to the smelters and decreased as distances from the smelters increased. The relation of decreasing amounts of metals in body tissues with increasing distance from the smelters also held true for amphibians and mammals. An exception to this relation was higher level of Cu in red-lacked salamanders (Plethodon cinereus) captured {approx}17 km downwind than those captured {approx}12 km downwind. Levels of Zn, Pb, and Co in liver, kidney, and muscle tissue of white-footed mice (Peromyscus leucopus) were not different (P >0.05) among sites. Cadmium in kidneys in white-footed mice exceeded 10 mg&& which is reportedly considered an indication of environmental contamination. Levels of Cd in kidneys and liver of white-tailed deer (Odocoileus virginianus) at Palmerton were five times higher than those for white-tailed deer collected 180 km southwest of Palmerton in southcentral Pennsylvania. The abnormal amounts of metals in the tissues of terrestrial vertebrates, and the absence or low abundance of wildlife at Palmerton indicated that ecological processes within 5 km of the smelters were markedly influenced 6 yr after zinc smelting was discontinued. 41 refs., 5 figs., 4 tabs.

Storm, G.L. [Fish and Wildlife Service, University Park, PA (United States); Fosmire, G.J. [Dept. of Nutrition, University Park, PA (United States); Bellis, E.D. [Pennsylvania State Univ., University Park, PA (United States)

1994-05-01

64

Heavy metal fates in laboratory bioretention systems.  

PubMed

Key to managing heavy metals in bioretention is to understand their fates in bioretention facilities. In this study, pot prototypes filled with bioretention media were built to simulate the conditions of natural growth of plants. Synthetic runoff with different heavy metal loadings (copper, cadmium, lead, and zinc) was periodically applied. Metal accumulations in tissues of grasses -Panicum virgatum, Kentucky-31, and Bromus ciliatus, were investigated after 230d of growth and multiple runoff treatment events. After 183d of periodic runoff application, the concentrations of Zn, Cu, Pb and Cd with low and high loadings had the same trends in the plant tissues, Zn>Cu>Pb>Cd, following the trend of the input metal concentrations. The fates of input metals were 88-97% captured in soil media, 2.0-11.6% not captured by bioretention media, and 0.5-3.3% accumulated in plants. Compared to the metals retained by the soil, the percentages of input metals taken up by plants were relatively low due to the low plant biomass produced in this study. Greater biomass density would be required for the vegetation to have a valuable impact in prolonging the lifetime of a bioretention cell. PMID:17005239

Sun, Xueli; Davis, Allen P

2007-01-01

65

Toxicity assessment of heavy metal mixtures by Lemna minor L  

Microsoft Academic Search

The discharge of untreated electroplating wastewaters directly into the environment is a certain source of heavy metals in surface waters. Even though heavy metal discharge is regulated by environmental laws many small-scale electroplating facilities do not apply adequate protective measures. Electroplating wastewaters contain large amounts of various heavy metals (the composition depending on the facility) and the pH value often

Tea Horvat; Željka Vidakovi?-Cifrek; Višnja Oreš?anin; Mirta Tkalec; Branka Pevalek-Kozlina

2007-01-01

66

Biomonitoring Atmospheric Heavy Metals with Lichens: Theory and Application  

Microsoft Academic Search

Recent records of environmental contamination noted a moderate decrease of SO2 pollution, whereas the burden of atmospheric heavy metals is still considerable. The present review refers to the entrapment, uptake, and accumulation of heavy metals by lichen thalli, made apparent by parameters of lichen vitality and stress. The particulate nature of airborne heavy metals is made evident by parameters referring

J. Garty

2001-01-01

67

Tons of Heavy Metals in Mill Creek Sediments Heather Freeman  

E-print Network

objectives for this summer research were to: 1.) determine how much heavy metal pollution has accumulatedTons of Heavy Metals in Mill Creek Sediments Heather Freeman 8/30/99 Geology Department Advisors: Dr. Kees DeJong Dr. Barry Manyard Dr. David Nash #12;Tons of heavy metals in Mill Creek sediments

Maynard, J. Barry

68

Arbuscular Mycorrhizal Fungi Can Benefit Heavy Metal Tolerance and Phytoremediation  

ERIC Educational Resources Information Center

Sites contaminated by heavy metals, such as industrial waste sites, create unwelcoming environments for plant growth. Heavy metals can have a wide range of toxic effects such as replacing essential elements or disrupting enzyme function. While some heavy metals are essential to plant nutrition at low concentrations, high concentrations of any…

Forgy, David

2012-01-01

69

Differential responses of sweetpotato peroxidases to heavy metals  

Microsoft Academic Search

Oxidative stress is one of the major causes of damage in plants exposed to different types of environmental stress, including heavy metals. Accumulation of heavy metals in plants can disrupt many cellular functions and plant growth. To assess the contribution of oxidative stress to heavy metal toxicity in plants, young sweetpotato plants (Ipomoea batatas) were treated with increasing concentrations of

Yun-Hee Kim; Haeng-Soon Lee; Sang-Soo Kwak

2010-01-01

70

Enrichment of Heavy Metals in Sediment Resulting from Soil  

E-print Network

Enrichment of Heavy Metals in Sediment Resulting from Soil Erosion on Agricultural Fields J O H N N, Harpenden, Hertfordshire AL5 2JQ, U.K. Heavy metal pollution of soil and water is often associated concentrations of these heavy metals were up to 3.98 times higher in the sediment than in the parent soil

Quinton, John

71

Detection of Heavy Metal Ions in Drinking Water Using a  

E-print Network

Detection of Heavy Metal Ions in Drinking Water Using a High-Resolution Differential Surface-resolution differential surface plasmon resonance (SPR) sensor for heavy metal ion detection. The sensor surface using this sensor. Introduction The detection and quantification of heavy metal ions are important

Chen, Wilfred

72

REVIEW ARTICLE Heavy Metal Pollutants and Chemical Ecology: Exploring  

E-print Network

REVIEW ARTICLE Heavy Metal Pollutants and Chemical Ecology: Exploring New Frontiers Robert S. Boyd January 2010 # Springer Science+Business Media, LLC 2010 Abstract Heavy metals are an important class, as these may have harmful ecological outcomes. For example, recent explora- tions of heavy metals in freshwater

Boyd, Robert S.

73

Heavy metal removal from a multi-metal solution and wastewater by Salvinia natans  

Microsoft Academic Search

Salvinia showed capacity to accumulate and hence remove more than one heavy metal from multi-metal solutions, though efficiency for heavy metal uptake varied for each metal present in different combinations. The pattern of heavy metal accumulation was confirmed by energy-dispersive X-ray fluorescence (EDXRF) analysis. There was a gradual decrease in heavy metal content in the wastewater samples when fresh biomass

Bhupinder Dhir; Sheela Srivastava

2011-01-01

74

Remediation processes for heavy metals contaminated soils  

SciTech Connect

This paper provides information on selected technologies available for remediation of metal contaminated soils and industrial effluent solutions. Because some of the industrial sites are contaminated with organics (solvents, gasolines and oils), an effort has been made to introduce the most frequently used cost-effective cleanup methods, such as {open_quotes}bioventing{close_quotes} and {open_quotes}composting.{close_quotes} The microorganisms involved in these processes are capable of degrading organic soil contaminants to environmentally harmless compounds: water and carbon dioxide. Heavy metals and radionuclides contaminated mining and industrial sites can be remediated by using adapted heap and dump leaching technologies, which can be chemical in nature or bio-assisted. The importance of volume reduction by physical separation is discussed. A special attention is devoted to the remediation of soils by leaching (soil washing) to remove heavy metal contaminants, such as chromium, lead, nickel and cadmium. Furthermore, the applicability of biosorption technology in the remediation of heavy metals and radionuclides contaminated industrial waste waters and acidic mining effluent solutions was indicated. 60 refs., 9 figs.

Torma, G.A.; Torma, A.E. [AMROT International, Rio Rancho, NM (United States); Hsu, Pei-Cheng [Mining and Waste Management, Arvado, CO (United States)

1996-12-31

75

Heavy Metal Removal Potential of Dried Salvinia Biomass  

Microsoft Academic Search

Investigations were carried out to evaluate heavy metal adsorption capacity of Salvinia. Batch experiments showed that dry plant biomass possess good potential to adsorb heavy metals such as Ni, Co, Cr, Fe, and Cd. The metal adsorption increased with increase in initial metal concentration. The data obtained fitted well with Freundlich equilibrium isotherm. Further characterization of plant biomass showed presence

Bhupinder Dhir; Sekh A. Nasim; P. Sharmila; P. Pardha Saradhi

2009-01-01

76

Cellular mechanisms for heavy metal detoxification and tolerance  

Microsoft Academic Search

Heavy metals such as Cu and Zn are essential for normal plant growth, although elevated concentra- tions of both essential and non-essential metals can result in growth inhibition and toxicity symptoms. Plants possess a range of potential cellular mech- anisms that may be involved in the detoxification of heavy metals and thus tolerance to metal stress. These include roles for

J. L. Hall

2002-01-01

77

Biomonitoring of heavy metal availability in the marine environment  

Microsoft Academic Search

Biomonitors can be used to establish geographical and\\/or temporal variations in the bioavailabilities of heavy metals in the marine environment, offering time-integrated measures of those portions of the total ambient metal load that are of direct ecotoxicological relevance. Heavy metal biomonitors need to conform to certain required characteristics, not least being metal accumulators. Use of a suite of biomonitors allows

Philip S. Rainbow

1995-01-01

78

Effect of heavy metals on bacterial transport  

NASA Astrophysics Data System (ADS)

Adsorption of metals onto bacteria and soil takes place as stormwater runoff infiltrates into the subsurface. Changes in both bacterial surfaces and soil elemental content have been observed, and may alter the attachment of bacteria to soil surfaces. In this study, scanning electron microscopy (SEM) and Energy Dispersive X-ray Spectrometry (EDS) analyses were performed on soil samples equilibrated with synthetic stormwater amended with copper, lead and zinc. The results demonstrate the presence of copper and zinc on soil surfaces. To investigate bacterial attachment behavior, sets of batch sorption experiments were conducted on Escherichia Coli (E. coli) under different chemical conditions by varying solution compositions (nutrient solution vs synthetic stormwater). The adsorption data is best described using theoretical linear isotherms. The equilibrium coefficient (Kd) of E. coli is higher in synthetic stormwater than in nutrient solution without heavy metals. The adsorption of heavy metals onto bacterial surfaces significantly decreases their negative surface charge as determined via zeta potential measurements (-17.0±5.96mv for E. coli equilibrated with synthetic stormwater vs -21.6±5.45mv for E. coli equilibrated with nutrient solution), indicating that bacterial attachment may increase due to the attachment of metals onto bacterial surfaces and their subsequent change in surface charge. The attachment efficiency (?) of bacteria was also calculated and compared for both solution chemistries. Bacterial attachment efficiency (?) in synthetic stormwater is 0.997, which is twice as high as that in nutrient solution(? 0.465). The ratio of bacterial diameter : collector diameter suggests minimal soil straining during bacterial transport. Results suggest that the presence of metals in synthetic stormwater leads to an increase in bacterial attachment to soil surfaces. In terms of designing stormwater infiltration basins, the presence of heavy metals seems to reduce the soil depth required to achieve certain levels of bacterial removal. This study demonstrates the effect of chemical constituents in stormwater runoff on bacterial transport in the subsurface.

Zhang, H.; Olson, M. S.

2010-12-01

79

Heavy metal transfer from atmosphere to plants  

NASA Astrophysics Data System (ADS)

Heavy metal contamination due to traffic was studied in the water basin of the Aiguebelette lake (Savoie, France) in the alpine chain. It is surrounded by mountains and crossed by a highway on a 6-km-distance. Contamination of lichens, mosses, barks and dead leaves litters were submitted to a comparative study. The quantities of six metals (Pb, Al, Cd, Zn, Mn, Ni) were estimated in each of these materials. Except for Al which was highly concentrated in Xanthoria parietina and to a lesser extent in mosses, all the matrices accumulated the metals in a relatively similar way. The hyperaccumulation factor varied from 2 to 258, depending on the sampling point on the studied metal and on the matrix. Bark represented a long-term accumulator and contained more lead than the other matrices. In the studied water basin, a specific atmospheric movement allowed to distribute the contaminants far away from the highway, especially on the west slope of the highest mountain.

Asta, J.; Guillard, E.; Tissut, M.; Gaude, T.; Ravanel, P.

2003-05-01

80

Plant rhamnogalacturonan II complexation of heavy metal cations  

DOEpatents

The present invention provides rhamnogalacturonan-II (RG-II) and relates to its ability to complex specific multivalent heavy metal cations. In the presence of boric acid, RG-II monomers form dimers that are cross-linked by a borate ester. The yield of such borate ester cross-linked dimers of RG-II is enhanced in the presence of specific heavy metal cations. The present invention further relates to the utility of RG-II in assays for the detection of specific heavy metal contamination; as a reagent useful in the removal of specific heavy metal cations contaminating foods and liquids, for example, fish, wines, etc.; as a pharmaceutical composition useful as an antidote in specific heavy metal cation poisoning; as a treatment for the detoxification of specific heavy metal cations from blood and/or tissues; and in a method of remediation of waters and soils contaminated with specific heavy metal cations.

O'Neill, Malcolm A. (Winterville, GA); Pellerin, Patrice J. M. (Montpellier, FR); Warrenfeltz, Dennis (Athens, GA); Vidal, Stephane (Combaillaux, FR); Darvill, Alan G. (Athens, GA); Albersheim, Peter (Athens, GA)

1999-01-01

81

Plant rhamnogalacturonan II complexation of heavy metal cations  

DOEpatents

The present invention provides rhamnogalacturonan-II (RG-II) and relates to its ability to complex specific multivalent heavy metal cations. In the presence of boric acid, RG-II monomers form dimers that are cross-linked by a borate ester. The yield of such borate ester cross-linked dimers of RG-II is enhanced in the presence of specific heavy metal cations. The present invention further relates to the utility of RG-II in assays for the detection of specific heavy metal contamination; as a reagent useful in the removal of specific heavy metal cations contaminating foods and liquids, for example, fish, wines, etc.; as a pharmaceutical composition useful as an antidote in specific heavy metal cation poisoning; as a treatment for the detoxification of specific heavy metal cations from blood and/or tissues; and in a method of remediation of waters and soils contaminated with specific heavy metal cations. 15 figs.

O`Neill, M.A.; Pellerin, P.J.M.; Warrenfeltz, D.; Vidal, S.; Darvill, A.G.; Albersheim, P.

1999-03-02

82

Quantum Criticality in Heavy Fermion Metals  

E-print Network

Quantum criticality describes the collective fluctuations of matter undergoing a second-order phase transition at zero temperature. Heavy fermion metals have in recent years emerged as prototypical systems to study quantum critical points. There have been considerable efforts, both experimental and theoretical, which use these magnetic systems to address problems that are central to the broad understanding of strongly correlated quantum matter. Here, we summarize some of the basic issues, including i) the extent to which the quantum criticality in heavy fermion metals goes beyond the standard theory of order-parameter fluctuations, ii) the nature of the Kondo effect in the quantum critical regime, iii) the non-Fermi liquid phenomena that accompany quantum criticality, and iv) the interplay between quantum criticality and unconventional superconductivity.

Philipp Gegenwart; Qimiao Si; Frank Steglich

2008-01-31

83

Extractable heavy metals in Atlantic coast soils  

Microsoft Academic Search

The analysis of soils, using 0.1 N HC1 as an extractant for the heavy metals, Cd, Cr, Ni and Pb on “fine”; textured North Shore and “coarse”; textured Annapolis Valley soils was completed. Results show ranges of 0.012 to 0.469 parts per million Cd; 0.102 to 2.90 parts per million Cr; 0.16 to 29.25 parts per million Ni and 0.12

Kenneth S. MacLean; Winston M. Langille

1980-01-01

84

Earthworm contamination by PCBs and heavy metals  

SciTech Connect

A comparison is made of soil and earthworm contamination by PCBs and heavy metals between a nature reserve and two sites conditioned by the addition of sewage sludge and compost. The tissues and gut content of the earthworms shows a higher PCB concentration than that of the surrounding soil and also a difference in the fingerprint of some single PCB compounds. Earthworms display a selective accumulation of cadmium and zinc in their tissues and gut content.

Diercxsens, P.; de Weck, D.; Borsinger, N.; Rosset, B.; Tarradellas, J.

1985-01-01

85

Heavy metal movement in metal-contaminated soil profiles  

SciTech Connect

Heavy metal movement in soil profiles is a major environmental concern because even slow transport through the soil may eventually lead to deterioration of groundwater quality. In this study, three metal-contaminated soil (Fuquay, Dothan, and Clarendon) were selected from cropland were a high-metal flue dust had been applied annually for 6 years to raise soil pH, with application ending 4 years before sampling. One uncontaminated soil (Tifton) from the same physiographic area was also sampled as a control. Soil samples were collected in 15-cm increments from the surface to 105 cm in depth. Total contents of Zn, Cd, and Pb in the soils samples were determined. To better understand metal movement in relation to metal fractions in the soil profile, soil samples were also extracted sequentially for exchangeable (EXC), organic matter (OM), Mn oxide (MNO), amorphous Fe oxide (AFEO), crystalline Fe oxide (CFEO), and residual (RES) fractions. 35 refs., 6 figs., 2 tabs.

Li, Zhenbin; Shuman, L.M. [Univ. of Georgia, Griffin, GA (United States)] [Univ. of Georgia, Griffin, GA (United States)

1996-10-01

86

Phytoaccumulation of heavy metals by aquatic plants.  

PubMed

Three aquatic plants were examined for their ability to remove heavy metals from contaminated water: parrot feather (Myriophylhum aquaticum), creeping primrose (Ludwigina palustris), and water mint (Mentha aquatic). The plants were obtained from a Solar Aquatic System treating municipal wastewater. All the three plants were able to remove Fe, Zn, Cu, and Hg from the contaminated water. The average removal efficiency for the three plant species was 99.8%, 76.7%, 41.62%, and 33.9% of Hg, Fe, Cu, and Zn, respectively. The removal rates of zinc and copper were constant (0.48 mg/l/day for Zn and 0.11 mg/l/day for Cu), whereas those of iron and mercury were dependent on the concentration of these elements in the contaminated water and ranged from 7.00 to 0.41 mg/l/day for Fe and 0.0787 to 0.0002 mg/l/day for Hg. Parrot feather showed greater tolerance to toxicity followed by water mint and creeping primrose. The growth of creeping primrose was significantly affected by heavy metal toxicity. The selectivity of heavy metals for the three plant species was the same (Hg>Fe>Cu>Zn). The mass balance preformed on the system showed that about 60.45-82.61% of the zinc and 38.96-60.75% of the copper were removed by precipitation as zinc phosphate and copper phosphate, respectively. PMID:14680885

Kamal, M; Ghaly, A E; Mahmoud, N; Côté, R

2004-02-01

87

Biosorption of heavy metals by Saccharomyces cerevisiae: A review  

Microsoft Academic Search

Heavy metal pollution has become one of the most serious environmental problems today. Biosorption, using biomaterials such as bacteria, fungi, yeast and algae, is regarded as a cost-effective biotechnology for the treatment of high volume and low concentration complex wastewaters containing heavy metal(s) in the order of 1 to 100 mg\\/L. Among the promising biosorbents for heavy metal removal which have

Jianlong Wang; Can Chen

2006-01-01

88

Heavy metal pollution and mineralisation of nitrogen in forest soils  

Microsoft Academic Search

LITTER decomposition and soil enzymatic activity in forests surrounding metal-processing industries are influenced by high concentrations of deposited heavy metals1-2. Very little seems to be known about the effects of heavy metal pollution on nitrogen mineralisation rates in natural soils. Reports on nitrogen mineralisation and nitrification rates after addition of heavy metal salts to mineral soils are not quite unanimous3-6.

Germund Tyler

1975-01-01

89

Assessment of Heavy Metal Pollution in Ibër River Sediment, Kosova  

Microsoft Academic Search

Natural environment which is polluting by heavy elements is considered as a universal problem. The heavy metals released in the environment as the result of human activities, atmospheric depositions and erosions would finally enter in to the aqua systems. Since, heavy metals are toxic, stable in the environment and potential to combine with the nutritive continuum. Thus, they are considered

Fatos Rexhepi; Ardian Rugova; Tahir Arbneshi

2010-01-01

90

Heavy Metal Pollution in Landfill Environment: A Malaysian Case Study  

Microsoft Academic Search

Heavy metal contamination of soil is of major concern from an ecological point of view. This study aims to characterize soil samples from different sites of two waste disposal grounds in Malaysia, to study heavy metal contamination in the landfill environment. The soil samples were obtained at different depths from 2m to 35m deep to find the possibility of heavy

P. Agamuthu; S. H. Fauziah

2010-01-01

91

Material Removes Heavy Metal Ions From Water  

NASA Technical Reports Server (NTRS)

New high capacity ion-exchange polymer material removes toxic metal cations from contaminated water. Offers several advantages. High sensitivities for such heavy metals as lead, cadmium, and copper and capable of reducing concentrations in aqueous solutions to parts-per-billion range. Removes cations even when calcium present. Material made into variety of forms, such as thin films, coatings, pellets, and fibers. As result, adapted to many applications to purify contaminated water, usually hard wherever found, whether in wastewater-treatment systems, lakes, ponds, industrial plants, or homes. Another important feature that adsorbed metals easily reclaimed by either destructive or nondestructive process. Other tests show ion-exchange polymer made inexpensively; easy to use; strong, flexible, not easily torn; and chemically stable in storage, in aqueous solutions, and in acidic or basic solution.

Philipp, Warren H., Jr.; Street, Kenneth W.; Hill, Carol; Savino, Joseph M.

1995-01-01

92

Heavy metals in common foodstuff: Daily intake  

SciTech Connect

Lately, toxic effects of some heavy metals (Pb, Cd) as well as desirable ones of some others (Ni, Mn, Zn) have been a field of thorough investigation. The main way of human body fortification in metals is through foodchain depending on the kind and quantity of the consumed food, according to dietary habits. The purpose of this study is the calculation of metals daily intake through common foodstuff of Greek inhabitants. The calculation is based on results from quantitative analysis of Pb, Cd, Ni, Mn, and Zn in common foodstuff from the market of the city of Thessaloniki. The daily food consumption data is derived from three sources: (a) answers to a questionnaire distributed to families of the city of Thessaloniki, (b) nutrition data provided by the Agricultural Bank of Greece and (c) nutrition data according to international bibliography.

Tsoumbaris, P.; Tsoukali-Papadopoulou, H. (Univ. of Thessaloniki (Greece))

1994-07-01

93

Biosorption of heavy metals from landfill leachate onto activated sludge.  

PubMed

The removal of various heavy metals was studied when activated sludge was exposed to heavy metals in landfill leachate. Batch uptake tests were conducted for this purpose. Adsorption was the main mechanism of removal when biomass was contacted with heavy metals. Activated sludge had a high biosorption capacity and equilibrium was reached in a short time with respect to copper, iron, manganese, zinc and chromium. Adsorption isotherms were generated for those heavy metals and the Freundlich constants were calculated. Among the metals studied, manganese became very concentrated on activated sludge with time. PMID:11501320

Ceçen, F; Gürsoy, G

2001-01-01

94

Ion exchange extraction of heavy metals from wastewater sludges.  

PubMed

Heavy metals are common contaminants of some industrial wastewater. They find their way to municipal wastewaters due to industrial discharges into the sewerage system or through household chemicals. The most common heavy metals found in wastewaters are lead, copper, nickel, cadmium, zinc, mercury, arsenic, and chromium. Such metals are toxic and pose serious threats to the environment and public health. In recent years, the ion exchange process has been increasingly used for the removal of heavy metals or the recovery of precious metals. It is a versatile separation process with the potential for broad applications in the water and wastewater treatment field. This article summarizes the results obtained from a laboratory study on the removal of heavy metals from municipal wastewater sludges obtained from Ardhiya plant in Kuwait. Data on heavy metal content of the wastewater and sludge samples collected from the plant are presented. The results obtained from laboratory experiments using a commercially available ion exchange resin to remove heavy metals from sludge were discussed. A technique was developed to solubilize such heavy metals from the sludge for subsequent treatment by the ion exchange process. The results showed high efficiency of extraction, almost 99.9%, of heavy metals in the concentration range bound in wastewater effluents and sludges. Selective removal of heavy metals from a contaminated wastewater/sludge combines the benefits of being economically prudent and providing the possibility of reuse/recycle of the treated wastewater effluents and sludges. PMID:15027828

Al-Enezi, G; Hamoda, M F; Fawzi, N

2004-01-01

95

Heavy Metal Tolerance Robert S. Boyd, Nishanta Rajakaruna  

E-print Network

on various metals (some of which are quite toxic) and these industries have resulted in pollution that can be useful to solve environmental problems caused by heavy metal pollution. General Overviews General and Kabata-Pendias 2010 provide useful summaries on specific heavy metals and their interactions with soils

Rajakaruna, Nishanta

96

BIOALGA reactor: preliminary studies for heavy metals removal  

Microsoft Academic Search

Microalgae have a high affinity for polyvalent metals, for that reason they could be used to reduce the concentration of heavy metals present in water and wastewater. In the present work an evaluation of a rotary biofilm reactor for algae immobilization (BIOALGA) with the subject of heavy metal removal was investigated. The BIOALGA reactor consisted of a pilot scale model

L Travieso; A Pellón; F Ben??tez; E Sánchez; R Borja; N O’Farrill; P Weiland

2002-01-01

97

Facultative hyperaccumulation of heavy metals and metalloids.  

PubMed

Approximately 500 species of plants are known to hyperaccumulate heavy metals and metalloids. The majority are obligate metallophytes, species that are restricted to metalliferous soils. However, a smaller but increasing list of plants are "facultative hyperaccumulators" that hyperaccumulate heavy metals when occurring on metalliferous soils, yet also occur commonly on normal, non-metalliferous soils. This paper reviews the biology of facultative hyperaccumulators and the opportunities they provide for ecological and evolutionary research. The existence of facultative hyperaccumulator populations across a wide edaphic range allows intraspecific comparisons of tolerance and uptake physiology. This approach has been used to study zinc and cadmium hyperaccumulation by Noccaea (Thlaspi) caerulescens and Arabidopsis halleri, and it will be instructive to make similar comparisons on species that are distributed even more abundantly on normal soil. Over 90% of known hyperaccumulators occur on serpentine (ultramafic) soil and accumulate nickel, yet there have paradoxically been few experimental studies of facultative nickel hyperaccumulation. Several hypotheses suggested to explain the evolution of hyperaccumulation seem unlikely when most populations of a species occur on normal soil, where plants cannot hyperaccumulate due to low metal availability. In such species, it may be that hyperaccumulation is an ancestral phylogenetic trait or an anomalous manifestation of physiological mechanisms evolved on normal soils, and may or may not have direct adaptive benefits. PMID:24467891

Pollard, A Joseph; Reeves, Roger D; Baker, Alan J M

2014-03-01

98

Heavy metal uptake by natural zeolite and metals partitioning in sewage sludge compost  

Microsoft Academic Search

A major limitation of land application of sewage sludge compost is the potential high heavy metal content due to the metal content of the original sludge. Zeolites may be useful as metal scavengers in metal-rich sludges. The natural zeolite, clinoptilolite has the ability to take up heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn). The aim of the

A. A Zorpas; T Constantinides; A. G Vlyssides; I Haralambous; M Loizidou

2000-01-01

99

Heavy metal retention of different embankments  

NASA Astrophysics Data System (ADS)

The accumulation and retention of heavy metals in roadside soils has been studied for at least over forty years, but it is still subject of major interest. The continuously increasing road traffic induces high heavy metal loadings in runoff and seepage water. Elevated concentrations of heavy metals are a potential environmental risk. Especially in the long term development there is an increasing problem of soil contamination and groundwater pollution. A significant rate of road runoff infiltrates into the hard and soft shoulder. They are usually built during road construction and located directly along the road edge. According to valid german law, newly constructed hard shoulders have to provide a specific bearing capacity to enable trafficability in emergency cases. Therefore the applicable materials consist of defined gravel-soil mixtures, which can fulfill this requirement. To determine and compare the concentration of Pb, Cd, Zn, Cu, Ni, Cr in the road runoff and seepage water of different hard shoulder substrates, we installed 6 lysimeters along the edge of the german highway A115. Three lysimeters were filled with different materials wich are commonly used for road construction in Germany and compacted afterwards. Surface runoff is sampled, as is seepage water in two depths in the three lysimeters. Furthermore three lysimeters where installed and filled with plain gravel, to observe the distribution, quantity and quality of road runoff. Additionally soil column experiments were carried out with the same construction material. Both, the measured seepage water concentrations from field and column experiments of Pb, Cd, Zn, Cu, Ni, Cr do not yet exceed the trigger values of the German Federal Soil Protection and Contamination Ordinance (BBodSchV). No significant differences in heavy metal concentrations of the three artificial hard shoulder lysimeters were determined so far. First analytical results of the road runoff show concentrations of up to 12.9 µg/l Pb, 0.1 µg/l Cd, 19.8 µg/l Cu, 3.9 µg/l Cr, and 49.6 µg/l Zn. They are in the same order of magnitude as literature values.

Werkenthin, Moritz; Kluge, Bjoern; Wessolek, Gerd

2013-04-01

100

A model for ph dependent equilibrium of heavy metal biosorption  

Microsoft Academic Search

Biosorption of heavy metals can be an effective process for the removal and recovery of heavy metal ions from aqueous solutions.\\u000a The biomass of marine macro algae has been reported to have high uptake capacities for a number of heavy metal ions and the\\u000a uptake capacities are strongly influenced by the value of the solution pH. In this paper, a

Qiming Yu; Pairat Kaewsarn

1999-01-01

101

Reduction of heavy metal load in food chain: technology assessment  

Microsoft Academic Search

Industrialization and urbanization activities lead to extensive environmental problems and one of the most challenging problems\\u000a is heavy metal contamination. Heavy metal is responsible for causing adverse effect on human health through food chain contamination.\\u000a To minimize the effect, different methods are being used for decreasing heavy metal load into the food chain. Most of the\\u000a traditional methods are either

Anita Singh; Sheo Mohan Prasad

102

Rehabilitation Methods for Exposure to Heavy Metals Under Environmental Conditions  

Microsoft Academic Search

\\u000a Heavy metals, anthropogenic toxicants, can penetrate into the human organism in tiny amounts through food and water and then\\u000a accumulate, promoting development of chronic poisonings and the reduction of human adaptability to the environment. Modeling\\u000a of heavy metal anthropogenic pollution makes it possible to study the mechanism and nature of heavy metals pathological effect\\u000a on humans and animals. The knowledge

A. R. Gutnikova; B. A. Saidkhanov; I. V. Kosnikova; I. M. Baybekov; K. O. Makhmudov; D. D. Ashurova; A. K. H. Islamov; M. I. Asrarov

103

Arbuscular Mycorrhiza, Heavy Metal,and Salt Tolerance  

Microsoft Academic Search

More than 80% of all higher plants are colonized by arbuscular mycorrhizal fungi (AMF) under diverse stress conditions. The\\u000a extent of mycorrhizal colonization in plants that grow in heavy metal soils (metallophytes) or salt marshes (halophytes) is\\u000a species dependent. Specially adapted AMF have repeatedly been reported to alleviate the toxicity of heavy metals to plants.\\u000a Factors governing the heavy metal

Hermann Bothe; Marjana Regvar; Katarzyna Turnau

104

Effects of Heavy metals on plants and resistance mechanisms  

Microsoft Academic Search

Goal, Scope and Background  As one of the consequences of heavy metal pollution in soil, water and air, plants are contaminated by heavy metals in some\\u000a parts of China. To understand the effects of heavy metals upon plants and the resistance mechanisms, would make it possible\\u000a to use plants for cleaning and remediating heavy metal-polluted sites.\\u000a \\u000a \\u000a \\u000a Methods  The research results on the

Shuiping Cheng

2003-01-01

105

Heavy metal atmospheric deposition and biomonitoring  

NASA Astrophysics Data System (ADS)

The atmospheric fluxes of heavy metals were measured continuously in the Paris area. The dry depositions were collected on quartz fiber filters, after comparison between clogging capacities and blank levels on commercial filters. Rain was collected in a polyethylene gauge. Two transplanted biomonitors, the epiphytic lichen Evernia prunastri, and the pleurocarpeous moss Scleropodium purum, were exposed simultaneously. These two common biomonitors have been used in previous passive biomonitoring campaigns [Galsomies 1999, Grasso 1999]. This work attempts to produce data on heavy metal exposure of this populated area near Paris, and to compare these two cryptogamic species behaviour. The results on bioaccumulation were compared to those given by a previous work in Italy [Bargagli, 2002] comparing the moss Hypnum cupressiforme and the lichen Parmelia caperata. In our study, the transplanted lichens were exposed in different conditions: to the rain or protected from rain, in vertical, horizontal or oblique position. Dry (filters) and wet (rain) depositions and biomonitors were analysed by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Neutron Activation Analysis (NAA) for more than 30elements [Ayrault, 2001]. The individual particle composition (on filters and cryptogams) was determined by nuclear microprobe (PIXE) and electron microprobe. The lichens displayed different accumulation rates, depending on exposition conditions. In particular, the inclination influenced the bulk concentrations in the lichen. Relation was made between fluxes and concentration accumulated by the biomonitors. The enrichment factors were spectacular for some elements, e.g. lead.

Ayrault, S.; Clocchiatti, R.; Carrot, F.; Michel, A.; Gaudry, A.; Moskura, M.

2003-05-01

106

Toxic Heavy Metals: Materials Cycle Optimization  

NASA Astrophysics Data System (ADS)

Long-term ecological sustainability is incompatible with an open materials cycle. The toxic heavy metals (arsenic, cadmium, chromium, copper, lead, mercury, silver, uranium/plutonium, zinc) exemplify the problem. These metals are being mobilized and dispersed into the environment by industrial activity at a rate far higher than by natural processes. Apart from losses to the environment resulting from mine wastes and primary processing, many of these metals are utilized in products that are inherently dissipative. Examples of such uses include fuels, lubricants, solvents, fire retardants, stabilizers, flocculants, pigments, biocides, and preservatives. To close the materials cycle, it will be necessary to accomplish two things. The first is to ban or otherwise discourage (e.g., by means of high severance taxes on virgin materials) dissipative uses of the above type. The second is to increase the efficiency of recycling of those materials that are not replaceable in principle. Here, also, economic instruments (such as returnable deposits) can be effective in some cases. A systems view of the problem is essential to assess the cost and effectiveness of alternative strategies.

Ayres, Robert U.

1992-02-01

107

Heavy Metals Toxicity and the Environment  

PubMed Central

Heavy metals are naturally occurring elements that have a high atomic weight and a density at least 5 times greater than that of water. Their multiple industrial, domestic, agricultural, medical and technological applications have led to their wide distribution in the environment; raising concerns over their potential effects on human health and the environment. Their toxicity depends on several factors including the dose, route of exposure, and chemical species, as well as the age, gender, genetics, and nutritional status of exposed individuals. Because of their high degree of toxicity, arsenic, cadmium, chromium, lead, and mercury rank among the priority metals that are of public health significance. These metallic elements are considered systemic toxicants that are known to induce multiple organ damage, even at lower levels of exposure. They are also classified as human carcinogens (known or probable) according to the U.S. Environmental Protection Agency, and the International Agency for Research on Cancer. This review provides an analysis of their environmental occurrence, production and use, potential for human exposure, and molecular mechanisms of toxicity, genotoxicity, and carcinogenicity. PMID:22945569

Tchounwou, Paul B; Yedjou, Clement G; Patlolla, Anita K; Sutton, Dwayne J

2013-01-01

108

Toxic heavy metals: materials cycle optimization.  

PubMed Central

Long-term ecological sustainability is incompatible with an open materials cycle. The toxic heavy metals (arsenic, cadmium, chromium, copper, lead, mercury, silver, uranium/plutonium, zinc) exemplify the problem. These metals are being mobilized and dispersed into the environment by industrial activity at a rate far higher than by natural processes. Apart from losses to the environment resulting from mine wastes and primary processing, many of these metals are utilized in products that are inherently dissipative. Examples of such uses include fuels, lubricants, solvents, fire retardants, stabilizers, flocculants, pigments, biocides, and preservatives. To close the materials cycle, it will be necessary to accomplish two things. The first is to ban or otherwise discourage (e.g., by means of high severance taxes on virgin materials) dissipative uses of the above type. The second is to increase the efficiency of recycling of those materials that are not replaceable in principle. Here, also, economic instruments (such as returnable deposits) can be effective in some cases. A systems view of the problem is essential to assess the cost and effectiveness of alternative strategies. PMID:11607259

Ayres, R U

1992-01-01

109

Heavy metal removal potential of dried Salvinia biomass.  

PubMed

Investigations were carried out to evaluate heavy metal adsorption capacity of Salvinia. Batch experiments showed that dry plant biomass possess good potential to adsorb heavy metals such as Ni, Co, Cr, Fe, and Cd. The metal adsorption increased with increase in initial metal concentration. The data obtained fitted well with Freundlich equilibrium isotherm. Further characterization of plant biomass showed presence of both acidic and basic surface functionalities that might facilitate binding of metal ions. Fourier transform infrared (FTIR) spectra of plant biomass suggested involvement of carbonyl (C=O), carboxyl (-COO), and hydroxyl (-OH) groups in binding heavy metals to plant biomass. The studies establish S. natans as an effective biosorbent for removing heavy metals from wastewater and further emphasize biomass utilization in wastewater treatment technologies. PMID:20734611

Dhir, Bhupinder; Nasim, Sekh A; Sharmila, P; Saradhi, P Pardha

2010-02-01

110

Aquatic insects as biological monitors of heavy metal pollution  

Microsoft Academic Search

A mayfly,Ephemerella grandis, and a stonefly,Pteronarcys californica, were exposed to lead, zinc, copper, and silver to determine the acute metal toxicities. The insects tested were found to be more tolerant of the heavy metals than most fish. They concentrated the metals in relative proportion to the occurrence of the metals in the stream by some predictable, reproducible factor. These data,

R. Barry Nehring

1976-01-01

111

Heavy metals in garden soils along roads in Szeged, Hungary  

Microsoft Academic Search

The soils of the urban environment, owing to the various anthropogenic activities, can be contaminated by heavy metals. The traffic is well-known for more decades to be main source of heavy metals mostly in cities. The accumulation of these elements can have different effects, either directly endangering the natural soil functions, or indirectly endangering the biosphere by bio-accumulation and inclusion

Zsuzsanna Szolnoki; Andrea Farsang

2010-01-01

112

HEAVY METAL TOXICITY OF RIVER RAVI AQUATIC ECOSYSTEM  

Microsoft Academic Search

The assessment of river water quality has been made by physico-chemical and biological analyses. The role ofplankton as indicators offreshwater contamination by heavy metals viz. zinc, iron, manganese, cadmium, lead and nickel has been studied through the computation ofregression models. Significant variations in the concentration of heavy metals in water were due to changes in the volume of untreated industrial

Muhammad Javed; S. Hayat

1999-01-01

113

REMOVAL OF HEAVY METALS USING ALUMINUM SALTS FOR PHOSPHORUS REMOVAL  

EPA Science Inventory

The use of aluminum salts to remove phosphorus is common practice. It has been shown that aluminum salts are also capable of removing heavy metals, but the dosages were much greater than normally applied for phosphorus removal. This study investigates the removal of heavy metals ...

114

Heavy Metal Music and Reckless Behavior among Adolescents.  

ERIC Educational Resources Information Center

Fifty-four male and 30 female adolescents who like heavy metal music were compared on various outcome variables to 56 male and 105 female peers who do not like it. Those who like heavy metal report a wider range of reckless behavior than those who do not like it. (SLD)

Arnett, Jeffrey

1991-01-01

115

Heavy Metal Music and Adolescent Suicidality: An Empirical Investigation.  

ERIC Educational Resources Information Center

Investigates the relationship between preference for heavy metal music and vulnerability to suicide among high school students. Results indicate that preference for heavy metal music among adolescents may be sign of increased suicidal vulnerability, but also suggests that the source of the problem may lie more in personal and familial…

Scheel, Karen R.; Westefeld, John S.

1999-01-01

116

Toxicity of heavy metals to thermophilic anaerobic digestion  

Microsoft Academic Search

The effects of heavy metals on the thermophilic digestion of sewage sludge was studied in three semicontinuous digesters step-fed with cadmium, copper and nickel, respectively. The daily gas production, gas composition, the quantitative accumulation of volatile fatty acids, and the distribution of the heavy metals were measured. The fermentations were carried out at 58°C with a retention time of 10

B. K. Ahring; P. Westermann

1983-01-01

117

STAINING OF TISSUE SECTIONS FOR ELECTRON MICROSCOPY WITH HEAVY METALS  

Microsoft Academic Search

ABS>Heavy metals may be incorporated from solution into tissue sections ; for electron microscopy. The resulting increase in density of the tissue ; provides greatly enhanced contrast with minimal distortion. Relative densities ; of various structures are found to depend on the heavy metal ions present and on ; the conditions of staining. Certain hitherto unobserved details are revealed and

M. L. Watson

1958-01-01

118

Permeable Reactive Biobarriers for the Containment of Heavy Metal  

E-print Network

and Environmental Engineering University of Arizona #12;What Is Acid Mine Drainage? Acid Mine Drainage (AMDPermeable Reactive Biobarriers for the Containment of Heavy Metal Contamination in Acid Mine) is defined as the presence heavy metals, increased acidity, and sulfate as a direct result of mining

Fay, Noah

119

Coal burning leaves toxic heavy metal legacy in the Arctic  

Microsoft Academic Search

Toxic heavy metals emitted by industrial activities in the midlatitudes are transported through the atmosphere and deposited in the polar regions; bioconcentration and biomagnification in the food chain mean that even low levels of atmospheric deposition may threaten human health and Arctic ecosystems. Little is known about sources and long-term trends of most heavy metals before ≈1980, when modern measurements

Joseph R. McConnell; Ross Edwards

2008-01-01

120

Heavy metal pollution of soils and crops in Northern Bohemia  

Microsoft Academic Search

Heavy metal contamination of agricultural crops and soils was investigated during 1987–1992 in 5 selected regions of the Czech Republic which are differently polluted by industrial emissions. The monitoring network included nearly 200 individual plots situated in the 5 above mentioned regions. Agrolandscapes, soils and crops typical of Bohemia, were investigated. Seven heavy metals (HM) (Cd, Pb, Hg, Co, Cr,

S. Ustyak; V. Petrikova

1996-01-01

121

Monitoring and preventive measures about heavy metal pollution  

Microsoft Academic Search

taking overmuch in toxic heavy metal elements will lead to reduce of personal immunity or become permanently disabled, even death. In local region, the soils and water bodies which persons rely for existence had been contaminated, which the toxic heavy metal elements had been accumulated over a long period of time because it is difficult to degradation by microorganism, and

Wenyuan Li

2011-01-01

122

BIOTESTING OF HEAVY METAL POLLUTION IN THE SOIL  

Microsoft Academic Search

Biotesting of heavy metal pollution in the soil. Chemical pollution of the environment increases sharply globally, and one of the most significant indicator of this increasing pollution is the accumulation of heavy metals in the soil. In mobile forms they can enter the food chain, damaging the environment seriously and posing a risk to human health. The subject of this

György FÜLEKY; Szilvia BARNA

2008-01-01

123

Heavy metals in wild rice from northern Wisconsin  

Microsoft Academic Search

Wild rice grain samples from various parts of the world have been found to have elevated concentrations of heavy metals, raising concern for potential effects on human health. It was hypothesized that wild rice from north-central Wisconsin could potentially have elevated concentrations of some heavy metals because of possible exposure to these elements from the atmosphere or from water and

James P. Bennett; Esteban Chiriboga; John Coleman; Donald M. Waller

2000-01-01

124

Heavy metal uptake by marsh plants in hydroponic solution cultures  

Microsoft Academic Search

Eight marsh plants were grown in chemically controlled hydroponic solutions containing three concentrations of heavy metals to evaluate the ability of each plant species to take up and accumulate heavy metals. The marsh plants studited were Cyperus esculentus, Scirpus validus, Spartina patens, Scirpus robustus, Distichiis spicata, Triglochin maritima, Spartina alterniflora, and Spartina foliosa. These species represented freshwater, brackish water, and

C. R. Lee; T. C. Sturgis; M. C. Landin

1981-01-01

125

BIOACCUMULATION OF HEAVY METALS BY LITTORAL AND PELAGIC MARINE ORGANISMS  

EPA Science Inventory

Marine organisms appear to be useful indicators of heavy metal pollution in the marine environment. In order to test this concept, research was performed to determine the levels of heavy metals in selected indicator organisms. Several approaches were used. The first was to select...

126

ENZYME-MEDIATED TRANSFORMATIONS OF HEAVY METALS/METALLOIDS  

Technology Transfer Automated Retrieval System (TEKTRAN)

A major emphasis has been placed on the bioremediation of organic compounds and their fate and transport throughout the environment. However, another important class of chemicals polluting our environment are inorganic, particularly heavy metals and metalloids. Heavy metals are elements of the Per...

127

SALINITY-HEAVY METAL INTERACTIONS IN FOUR SALTTOLERANT PLANT SPECIES  

Microsoft Academic Search

The concurrent effect of NaCl salinity and heavy metals [cadmium (Cd), chromium (Cr) and nickel (Ni)] on growth, sodium (Na), and heavy metal accumulation was assessed in four salt tolerant plant species. These were: barley (Hordeum vulgare L.), purslane (Portulaca oleracea L.), Inula crithmoides L., and Plantago coronopus L., all of which have documented potential for use in saline agriculture.

R. A. Zurayk; N. F. Khoury; S. N. Talhouk; R. Z. Baalbaki

2001-01-01

128

Biosorption: An eco-friendly alternative for heavy metal removal  

Microsoft Academic Search

Heavy metals occur in immobilized form in sediments and as ores in nature. However due to various human activities like ore mining and industrial processes the natural biogeochemical cycles are disrupted causing increased deposition of heavy metals in terrestrial and aquatic environment. Release of these pollutants without proper treatment poses a significant threat to both environment and public health, as

Srinivasa Reddy Ronda; Vijaya Saradhi Settalluri; Koneru Lakshmaiah

2007-01-01

129

Heavy Metal Resistance of Biofilm and Planktonic Pseudomonas aeruginosa  

Microsoft Academic Search

A study was undertaken to examine the effects of the heavy metals copper, lead, and zinc on biofilm and planktonic Pseudomonas aeruginosa. A rotating-disk biofilm reactor was used to generate biofilm and free- swimming cultures to test their relative levels of resistance to heavy metals. It was determined that biofilms were anywhere from 2 to 600 times more resistant to

Gail M. Teitzel; Matthew R. Parsek

2003-01-01

130

Remediation of contaminated land by formation of heavy metal phosphates  

Microsoft Academic Search

Phosphate compounds of Pb and Zn are highly insoluble and their formation in contaminated soils would aid immobilisation of heavy metals. In preliminary experiments to induce heavy metal phosphates in soils, two mine-waste contaminated soils were treated by the addition of soluble inorganic phosphate and the growth of Agrostis capillaris on soil amended with horticultural peat. After incubation for three

S. Caporn

1996-01-01

131

REVIEW ARTICLE FOCUS Quantum criticality in heavy-fermion metals  

E-print Network

REVIEW ARTICLE FOCUS Quantum criticality in heavy-fermion metals Quantum criticality describes the collective fluctuations of matter undergoing a second-order phase transition at zero temperature. Heavy-fermion metals have in recent years emerged as prototypical systems to study quantum critical points. There have

Loss, Daniel

132

Selective assay for heavy metal toxicity using a fluorogenic substrate  

SciTech Connect

Chromogenic substrates have been generally used in enzymatic assays for the specific determination of heavy metal toxicity. A toxicity assay based on the specific inhibition of {beta}-galactosidase by heavy metals and using a fluorogenic substrate was evaluated for its sensitivity to heavy metals and organic toxicants. The toxicity assay, FluoroMetPLATE, was specific for heavy metals and was more sensitive than the widely used Microtox assay. Except for lead, the assay displayed sensitivity similar to that of the 48-h acute Ceriodaphnia dubia assay. Monitoring of industrial samples showed that the FluoroMetPLATE assay gave similar results as the daphnid toxicity assay for 22 of 29 samples. For the remaining samples, for which there was no agreement between the two tests, it was found that the toxicity was mostly due to organic toxicants, confirming the specificity of FluoroMetPLATE for heavy metal toxicity.

Jung, K.; Bitton, G.; Koopman, B. [Univ. of Florida, Gainesville, FL (United States). Dept. of Environmental Engineering Sciences

1996-05-01

133

Contamination of heavy metals in mangroves: A comparison between Cao Martn Pea and  

E-print Network

Contamination of heavy metals in mangroves: A comparison between Caño that contamination of heavy metals in mangroves decrease their chlorophyll levels and how heavy metals contamination has affected them. The images utilized

Gilbes, Fernando

134

Novel synthetic phytochelatin-based capacitive biosensor for heavy metal ion detection  

E-print Network

Novel synthetic phytochelatin-based capacitive biosensor for heavy metal ion detection Ibolya on synthetic phytochelatins for sensitive detection of heavy metals is described. Synthetic phytochelatin (Glu: Biosensors; Heavy metals; Phytochelatins; Capacitance 1. Introduction Evolution of our society has lead

Chen, Wilfred

135

Hydroponic phytoremediation of heavy metals and radionuclides  

SciTech Connect

It is estimated that the Departments of Defense, Energy, and Agriculture will spend up to 300 billion federal dollars on environmental remediation during the next century. Current remediation processes can be expensive, non-aesthetic, and non-versatile. Therefore, the need exists for more innovative and cost effective solutions. Phytoremediation, the use of vegetation for the remediation of contaminated sediments, soils, and ground water, is an emerging technology for treating several categories of persistent, toxic contaminants. Although effective, phytoremediation is still in a developmental stage, and therefore is not a widely accepted technology by regulatory agencies and public groups. Research is currently being conducted to validate the processes effectiveness as well as increase regulatory and community acceptance. This research will focus on the ability of plants to treat an aquifer contaminated with heavy metals and radionuclides. Specifically, the effectiveness of hydroponically grown dwarf sunflowers and mustard seed will be investigated.

Hartong, J.; Szpak, J.; Hamric, T.; Cutright, T.

1998-07-01

136

Heavy metal retention of different roadside soils  

NASA Astrophysics Data System (ADS)

Emissions from major highways contain different kinds of contaminants such as heavy metals, polycyclic aromatic hydrocarbons and road salts which can occur in both particulate and dissolved form. Pollutants are transferred to the environment via aerial transport or the infiltration of road runoff and spray water. A significant rate of the road runoff infiltrates into the Embankment which is usually built during road construction and located next to the road edge. Especially in the long term development there is an increasing problem of soil contamination and groundwater pollution. According to valid German law, newly constructed hard shoulders have to provide a specific bear-ing capacity to enable trafficability in emergency cases. Therefore the applicable materials consist of accurately defined gravel-soil mixtures, which can fulfil this requirement. To determine and com-pare the total and dissolved concentrations of Pb, Cd, Zn, Cu, Ni, Cr in the road runoff and seep-age water of newly constructed embankments, we installed 6 Lysimeter along the edge of the German highway A115. Three lysimeter were filled with different materials which are recently used for embankment construction in Germany. Three further lysimeter where installed and filled with plain gravel, to observe the distribution, quantity and quality of road runoff. Fist results showed that heavy metal concentrations determined in the road runoff were compara-ble to literature values. The solute concentrations in the seepage water of the different embank-ment materials do not show considerable differences and exceed the trigger values of the German Federal Soil Protection & Contamination Ordinance (BBodSchV) only sporadically. Total concentra-tions of the seepage water are significantly higher than solute concentrations and clearly differ be-tween stable and non stable variant. In order to estimate the risk of groundwater pollution further monitoring of seepage water quality is necessary.

Werkenthin, Moritz; Kluge, Björn; Wessolek, Gerd

2014-05-01

137

Fate and effects of heavy metals on the Arkansas river  

SciTech Connect

The project examined fate and effects of heavy metals on biological communities in the upper Arkansas River Basin. The principal objectives of the research were: (1) to measure the impact of heavy metals (Cd, Cu, and Zn) on benthic invertebrate communities in the Arkansas River; (2) to delineate zones of high impact, moderate impact, and recovery based on the distribution and abundance of these organisms; (3) to examine seasonal variation in effects of metals on benthic communities; (4) to examine the potential transfer of heavy metals from benthic invertebrates to brown trout, Salmo trutta.

Clements, W.H.

1991-12-15

138

Decomposition of heavy metal contaminated nettles ( Urtica dioica L.) in soils subjected to heavy metal pollution by river sediments  

Microsoft Academic Search

Two incubation experiments were conducted to evaluate differences in the microbial use of non-contaminated and heavy metal contaminated nettle (Urtica dioica L.) shoot residues in three soils subjected to heavy metal pollution (Zn, Pb, Cu, and Cd) by river sediments. The microbial use of shoot residues was monitored by changes in microbial biomass C, biomass N, biomass P, ergosterol, N

Khalid Saifullah Khan; Rainer Georg Joergensen

2006-01-01

139

Biomedical Implications of Heavy Metals Induced Imbalances in Redox Systems  

PubMed Central

Several workers have extensively worked out the metal induced toxicity and have reported the toxic and carcinogenic effects of metals in human and animals. It is well known that these metals play a crucial role in facilitating normal biological functions of cells as well. One of the major mechanisms associated with heavy metal toxicity has been attributed to generation of reactive oxygen and nitrogen species, which develops imbalance between the prooxidant elements and the antioxidants (reducing elements) in the body. In this process, a shift to the former is termed as oxidative stress. The oxidative stress mediated toxicity of heavy metals involves damage primarily to liver (hepatotoxicity), central nervous system (neurotoxicity), DNA (genotoxicity), and kidney (nephrotoxicity) in animals and humans. Heavy metals are reported to impact signaling cascade and associated factors leading to apoptosis. The present review illustrates an account of the current knowledge about the effects of heavy metals (mainly arsenic, lead, mercury, and cadmium) induced oxidative stress as well as the possible remedies of metal(s) toxicity through natural/synthetic antioxidants, which may render their effects by reducing the concentration of toxic metal(s). This paper primarily concerns the clinicopathological and biomedical implications of heavy metals induced oxidative stress and their toxicity management in mammals. PMID:25184144

Singh, Shweta; Siddiqi, Nikhat J.

2014-01-01

140

Remediation technologies for heavy metal contaminated groundwater.  

PubMed

The contamination of groundwater by heavy metal, originating either from natural soil sources or from anthropogenic sources is a matter of utmost concern to the public health. Remediation of contaminated groundwater is of highest priority since billions of people all over the world use it for drinking purpose. In this paper, thirty five approaches for groundwater treatment have been reviewed and classified under three large categories viz chemical, biochemical/biological/biosorption and physico-chemical treatment processes. Comparison tables have been provided at the end of each process for a better understanding of each category. Selection of a suitable technology for contamination remediation at a particular site is one of the most challenging job due to extremely complex soil chemistry and aquifer characteristics and no thumb-rule can be suggested regarding this issue. In the past decade, iron based technologies, microbial remediation, biological sulphate reduction and various adsorbents played versatile and efficient remediation roles. Keeping the sustainability issues and environmental ethics in mind, the technologies encompassing natural chemistry, bioremediation and biosorption are recommended to be adopted in appropriate cases. In many places, two or more techniques can work synergistically for better results. Processes such as chelate extraction and chemical soil washings are advisable only for recovery of valuable metals in highly contaminated industrial sites depending on economical feasibility. PMID:21708421

Hashim, M A; Mukhopadhyay, Soumyadeep; Sahu, Jaya Narayan; Sengupta, Bhaskar

2011-10-01

141

Heavy metals in Tuskegee Lake crayfish  

SciTech Connect

The crayfish, Onconectes virifis, is a bottom dweller and eats insect larvae, worms, crustaceans, small snails, fishes, and dead animal matter. They can be used to monitor the aquatic environment such as lakes, ponds and creeks. To monitor the environmental contamination of heavy metals (Hg, Pb, Cd, Cu, Co, Ni, and Zn) in Tuskegee Lake, Tuskegee, Alabama, adult crayfish were collected and analyzed for these metals. The Pb, Cd, Cu, Ni, and Zn concentrations were 3.91, 0.22, 8.06, 1.11, and 33.37 ppm in muscle and 28.98, 1.15, 9.86, 2.1 8, and 32.62 ppm in exoskeleton of crayfish, respectively. The concentrations of Pb and Cd were significantly higher in exoskeleton than those of muscle. However, the concentrations of Cu, Ni, and Zn did not show any significant difference between the muscle and the exoskeleton of the crayfish. The concentrations of Hg and Co were undetected in both the exoskeleton and muscle of the crayfish.

Khan, A.T. [Tuskegee Univ., AL (United States). School of Veterinary Medicine

1995-12-31

142

Effect of Heavy Metals on, and Handling by, the Kidney  

Microsoft Academic Search

Heavy metals such as cadmium (Cd), mercury (Hg), lead (Pb), chromium (Cr) and platinum (Pt) are a major environmental and occupational hazard. Unfortunately, these non-essential elements are toxic at very low doses and non-biodegradable with a very long biological half-life. Thus, exposure to heavy metals is potentially harmful. Because of its ability to reabsorb and accumulate divalent metals, the kidney

Olivier Barbier; Grégory Jacquillet; Michel Tauc; Marc Cougnon; Philippe Poujeol

2005-01-01

143

Kinetics of heavy-metal removal and recovery in sepiolite  

Microsoft Academic Search

Fixed beds of Mg-enriched sepiolite were percolated through Co2+, Cu2+, Zn2+, Cd2+ and Pb2+ single- and multicomponent heavy-metal solutions to study both the dynamic interactions between mineral and heavy-metal cations and the ion-sorption kinetics. The metal concentrations in the eluates were determined by atomic adsorption and\\/or inductively-coupled plasma and kinetics by the classical kinetic approach, using isothermal experiments at room

M. F Brigatti; C Lugli; L Poppi

2000-01-01

144

Efflux-mediated heavy metal resistance in prokaryotes  

Microsoft Academic Search

What makes a heavy metal resistant bacterium heavy metal resistant? The mechanisms of action, physiological functions, and distribution of metal-exporting proteins are outlined, namely: CBA efflux pumps driven by proteins of the resistance–nodulation–cell division superfamily, P-type ATPases, cation diffusion facilitator and chromate proteins, NreB- and CnrT-like resistance factors. The complement of efflux systems of 63 sequenced prokaryotes was compared with

Dietrich H Nies

2003-01-01

145

Heavy metal displacement in chelate-irrigated soil during phytoremediation  

NASA Astrophysics Data System (ADS)

Heavy metals in wastewater sewage sludge (biosolids), applied to land, contaminate soils. Phytoremediation, the use of plants to clean up toxic heavy metals, might remove them. Chelating agents are added to soil to solubilize the metals for enhanced phytoextraction. Yet no studies follow the displacement and leaching of heavy metals in soil with and without roots following solubilization with chelates. The objective of this work was to determine the mobility of heavy metals in biosolids applied to the surface of soil columns (76 cm long; 17 cm diam.) with or without plants (barley; Hordeum vulgare L.). Three weeks after barley was planted, all columns were irrigated with the disodium salt of the chelating agent, EDTA (ethylenediamine tetraacetic acid) (0.5 g/kg soil). Drainage water, soil, and plants were analyzed for heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, Zn). Total concentrations of the heavy metals in all columns at the end of the experiment generally were lower in the top 30 cm of soil with EDTA than without EDTA. The chelate increased concentrations of heavy metals in shoots. With or without plants, the EDTA mobilized Cd, Fe, Mn, Ni, Pb, and Zn, which leached to drainage water. Drainage water from columns without EDTA had concentrations of these heavy metals below detection limits. Only Cu did not leach in the presence of EDTA. Even though roots retarded the movement of Cd, Fe, Mn, Ni, Pb, and Zn through the EDTA-treated soil from 1 d (Cd) to 5 d (Fe), the drainage water from columns with EDTA had concentrations of Cd, Fe, Mn, and Pb that exceeded drinking water standards by 1.3, 500, 620, and 8.6 times, respectively. Because the chelate rendered Cd, Fe, Mn, Ni, Pb, and Zn mobile, it is suggested that the theory for leaching of soluble salts, put forward by Nielsen and associates in 1965, could be applied to control movement of the heavy metals for maximum uptake during chelate-assisted phytoremediation.

Madrid, F.; Liphadzi, M. S.; Kirkham, M. B.

2003-03-01

146

Heavy Metal Content in Plants from Family Lamiaceae Cultivated in an Industrially Polluted Region  

Microsoft Academic Search

Peppermint (Mentha × piperita L.), sage (Salvia officinalis L.), and clary sage (Salvia sclarea L.), cultivated at selected distances from a heavy metal pollution source (the Non-Ferrous Metal Works near Plovdiv, Bulgaria) were examined for heavy metal accumulation. The content of heavy metals in the roots, stems, leaves, and inflorescences, plus the heavy metal concentration in the essential oils obtained

V. Angelova; K. Ivanov; R. Ivanova

2006-01-01

147

Microalgae - A promising tool for heavy metal remediation.  

PubMed

Biotechnology of microalgae has gained popularity due to the growing need for novel environmental technologies and the development of innovative mass-production. Inexpensive growth requirements (solar light and CO2), and, the advantage of being utilized simultaneously for multiple technologies (e.g. carbon mitigation, biofuel production, and bioremediation) make microalgae suitable candidates for several ecofriendly technologies. Microalgae have developed an extensive spectrum of mechanisms (extracellular and intracellular) to cope with heavy metal toxicity. Their wide-spread occurrence along with their ability to grow and concentrate heavy metals, ascertains their suitability in practical applications of waste-water bioremediation. Heavy metal uptake by microalgae is affirmed to be superior to the prevalent physicochemical processes employed in the removal of toxic heavy metals. In order to evaluate their potential and to fill in the loopholes, it is essential to carry out a critical assessment of the existing microalgal technologies, and realize the need for development of commercially viable technologies involving strategic multidisciplinary approaches. This review summarizes several areas of heavy metal remediation from a microalgal perspective and provides an overview of various practical avenues of this technology. It particularly details heavy metals and microalgae which have been extensively studied, and provides a schematic representation of the mechanisms of heavy metal remediation in microalgae. PMID:25528489

Suresh Kumar, K; Dahms, Hans-Uwe; Won, Eun-Ji; Lee, Jae-Seong; Shin, Kyung-Hoon

2015-03-01

148

Aquatic insects as biological monitors of heavy metal pollution.  

PubMed

A mayfly, Ephemerella grandis, and a stonefly, Pteronarcys californica, were exposed to lead, zinc, copper, and silver to determine the acute metal toxicities. The insects tested were found to be more tolerant of the heavy metals than most fish. They concentrated the metals in relative proportion to the occurrence of the metals in the stream by some predictable, reproducible factor. These data, together with field tests, indicate aquatic insects may serve as effective biological monitors of heavy metal pollution where fish-kills are involved. PMID:1252629

Nehring, R B

1976-02-01

149

Biosorption of heavy metals and uranium from dilute solutions  

SciTech Connect

Eichhornia crassipes approaches being a scourge in many parts of the world, choking waterways and hindering transport upon them. At the same time it is known to readily abstract heavy metal ions from water and, thus, aids in the removal of heavy metals found in such waters. This paper considers the possibility of using specific parts of the plant as an inexpensive adsorbent for the removal of heavy metals from contaminated chemical and mining industry waste waters. In particular the root of the plant was found to be an excellent accumulator of heavy metal ions including uranium from solution. It is also suggested that dried roots of the plant might be placed in simple bags and used in a very low cost metal ion removal system.

Schneider, I.A.H. [Federal Univ. of Rio Grande do Sul (Brazil); Misra, M.; Smith, R.W. [Univ. of Nevada, Reno, NV (United States). Mackay School of Mines

1995-08-01

150

Bioavailability of heavy metals and decontamination of soils by plants  

Microsoft Academic Search

Bioavailability of heavy metals in metal-contaminated soils depends on physical, chemical and biological factors. Physical (structure, penetrability) and chemical factors (Eh, pH, speciation, concentration) give the framework in which biological factors can modify the metal availability by release of oxygen, protons, and organic acids and by association with mycorrhizal fungi. With these conditions in mind, the possibilities of the use

W. H. O. Ernst

1996-01-01

151

Heavy metal pollution in China: Origin, pattern and control  

Microsoft Academic Search

Goal, Scope and Background  Heavy metal is among one of the pollutants, which cause severe threats to humans and the environment in China. The aim of\\u000a the present review is to make information on the source of heavy metal pollution, distribution of heavy metals in the environment,\\u000a and measures of pollution control accessible internationally, which are mostly published in Chinese.\\u000a \\u000a \\u000a \\u000a Methods  Information

Shuiping Cheng

2003-01-01

152

Heavy metals in livers and kidneys of goats in Alabama  

SciTech Connect

The popularity of goat farming is increasing in the southeastern region of the United States. Baseline values of Hg, Pb, and Cd are not available in goat tissues in the United States. These values are needed when monitoring food for heavy metal contamination which may be associated with urbanization and industrialization. Due to human activities or anthropogenic sources of metals in the environment, high concentrations of these metals have been observed in herbage and animal tissues. It has also been reported that toxic heavy metals are concentrated mostly in kidneys and livers of animals. The risk of exposure of humans to heavy metals contained in edible organs of animals has received widespread concern. The objectives of this study were to (i) measure the levels of Hg,Pb, and Cd in livers and kidneys of goats; and (ii) determine whether accumulation of these metals is related to age and/or sex. 20 refs., 3 tabs.

Khan, A.T.; Diffay, B.C.; Datiri, B.C. [Tuskegee Univ., AL (United States)

1995-10-01

153

Adsorption behavior of heavy metals on biomaterials.  

PubMed

We have investigated adsorption of Cd(II) and Pb(II) at pH 2-6.7 onto the biomaterials chitosan, coffee, green tea, tea, yuzu, aloe, and Japanese coarse tea, and onto the inorganic adsorbents, activated carbon and zeolite. High adsorptive capabilities were observed for all of the biomaterials at pH 4 and 6.7. In the adsorption of Cd(II), blend coffee, tea, green tea, and coarse tea have comparable loading capacities to activated carbon and zeolite. Although activated carbon, zeolite, and chitosan are utilized in a variety of fields such as wastewater treatment, chemical and metallurgical engineering, and analytical chemistry, these adsorbents are costly. On the other hand, processing of the test biomaterials was inexpensive, and all the biomaterials except for chitosan were able to adsorb large amounts of Pb(II) and Cd(II) ions after a convenient pretreatment of washing with water followed by drying. The high adsorption capability of the biomaterials prepared from plant materials is promising in the development of a novel, low-cost adsorbent. From these results, it is concluded that heavy metal removal using biomaterials would be an effective method for the economic treatment of wastewater. The proposed adsorption method was applied to the determination of amounts of Cd(II) and Pb(II) in water samples. PMID:15373400

Minamisawa, Mayumi; Minamisawa, Hiroaki; Yoshida, Shoichiro; Takai, Nobuharu

2004-09-01

154

Transport processes in heavy metal fluoride glasses  

NASA Astrophysics Data System (ADS)

Na self-diffusion, Li self-diffusion, Na+ Li+ ion exchange, electrical conductivity, and mechanical relaxation have been studied below Tg on glasses of the system ZrF4 BaF2 LaF3 AF (A=Na, Li), with A=10, 20, 30 mol%. Compared to the transport mechanism in alkali-containing silicate glasses, the mechanisms in these non-oxide glasses are anomalous. Thus the self-diffusion coefficient of Na decreases with increasing NaF content, whereas that of Li increases with increasing LiF content. Both the electrical conductivity and the Na+ Li+ ion exchange reach a minimum at ? 20 mol% LiF, and the mechanical relaxation shows one peak for the 20 and 30 mol% LiF-glasses and two peaks for the glass with 10 mol% LiF, evidencing both a contribution of F- and Li+ ions to the transport. Moreover, the presence of the three partially interacting mobile species F-, Na+, Li+ obviously leads to an anionic cationic mixed ion effect. Applying the Nernst Einstein equation to the Li+ transport in LiF-containing glasses shows that its mechanism is dissimilar to that in oxide glasses. Calculated short jump distances possibly can be interpreted as an Li+ movement via energetically suitable sites near F- ions. Likewise the Nernst Planck model, successfully applied to the ionic transport in mixed alkali silicate glasses, obviously does also not hold for the present heavy metal fluoride glasses.

Frischat, G. H.; Buksak, A.; Heide, G.; Roling, B.

2007-05-01

155

Contamination of Polish national parks with heavy metals.  

PubMed

The paper presents results of screening analysis of all Polish national parks (23) contamination with Cd, Cu, Pb and Zn on the basis of a three-level characteristic of heavy metal presence in Norway spruce stands: accumulation on the needle surface, concentration of heavy metals in spruce needles and concentration of bioavailable heavy metals in the soil. Based on the obtained results, the classification of forest ecosystem hazard in national parks with heavy metals was made using synthetic indicators. It was found out that Babiogórski, Magurski, Ojcowski and Gorcza?ski National Parks, located in the southern part of the country, were the most polluted with heavy metals. It is probably due to a higher industrial activity in this part of Poland and the transboundary transport of air pollutants. A little lower level of pollution was observed in Kampinoski National Park located in the middle of the country. The concentration of heavy metals found in needles from national parks does not seem to be harmful for the health status of the trees. Statistically significant correlation between all parameters, which was found for cadmium--the most mobile of the analysed elements--shows that this metal can be proposed as a marker to reflect present effect of industrial emission on forests. PMID:21842164

Staszewski, Tomasz; ?ukasik, W?odzimierz; Kubiesa, Piotr

2012-07-01

156

Heavy metals and epigenetic alterations in brain tumors.  

PubMed

Heavy metals and their derivatives can cause various diseases. Numerous studies have evaluated the possible link between exposure to heavy metals and various cancers. Recent data show a correlation between heavy metals and aberration of genetic and epigenetic patterns. From a literature search we noticed few experimental and epidemiological studies that evaluate a possible correlation between heavy metals and brain tumors. Gliomas arise due to genetic and epigenetic alterations of glial cells. Changes in gene expression result in the alteration of the cellular division process. Epigenetic alterations in brain tumors include the hypermethylation of CpG group, hypomethylation of specific genes, aberrant activation of genes, and changes in the position of various histones. Heavy metals are capable of generating reactive oxygen assumes that key functions in various pathological mechanisms. Alteration of homeostasis of metals could cause the overproduction of reactive oxygen species and induce DNA damage, lipid peroxidation, and alteration of proteins. In this study we summarize the possible correlation between heavy metals, epigenetic alterations and brain tumors. We report, moreover, the review of relevant literature. PMID:25646073

Caffo, Maria; Caruso, Gerardo; Fata, Giuseppe La; Barresi, Valeria; Visalli, Maria; Venza, Mario; Venza, Isabella

2014-12-01

157

DETERMINATION OF HEAVY METALS AND PESTICIDES IN GINSENG PRODUCTS  

EPA Science Inventory

Medicinal plants may carry residuals of environmentally persistent pesticides or assimilate heavy metals in varying degrees. Several factors may influence contaminant accumulation, including species, level and duration of contaminant exposure, and topography. As part of a progra...

158

Heavy metal induced physiological alterations in Salvinia natans.  

PubMed

Salvinia possess inherent capacity to accumulate high levels of various heavy metals. Accumulation of Cr, Fe, Ni, Cu, Pb and Cd ranged between 6 and 9 mg g(-1)dry wt., while accumulation of Co, Zn and Mn was ?4 mg g(-1)dry wt. Heavy metal accumulation affected the physiological status of plants. Photosystem II activity noted to decline in Ni, Co, Cd, Pb, Zn and Cu exposed plants, while Photosystem I activity showed enhancement under heavy metal stress in comparison to control. The increase in PS I activity supported build up of transthylakoidal proton gradient (?pH), which subsequently helped in maintaining the photophosphorylation potential. Ribulose 1,5 dicarboxylase/oxygenase (Rubisco) activity noted a decline. Alterations in photosynthetic potential of Salvinia result primarily from changes in carbon assimilation efficiency with slight variations in primary photochemical activities and photophosphorylation potential. Studies suggest that Salvinia possess efficient photosynthetic machinery to withstand heavy metal stress. PMID:21724257

Dhir, Bhupinder; Sharmila, P; Pardha Saradhi, P; Sharma, S; Kumar, R; Mehta, Devinder

2011-09-01

159

Heavy Metal Tolerance in Plants J.ANTONOVIOS  

E-print Network

. Species Present on Contaminated Soils . 6 1. Vascular Plants . . . . . . . . . . 5 2. Mosses . . . . . . . . . . . 16 B. Community Studies on Contaminated Soils . 17 C. Factors determining Plant Distribution#12;Heavy Metal Tolerance in Plants J.ANTONOVIOS Department of Biology. University of Stirling

Antonovics, Janis

160

View of interior detail; in kitchen; builtiniron and heavy metal ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of interior detail; in kitchen; built-in-iron and heavy metal clock. - Mare Island Naval Shipyard, Quarters P, Walnut Avenue, northwest corner of Walnut Avenue & Fifth Street, Vallejo, Solano County, CA

161

Heavy metal content of a medicinal moss tea for hypertension.  

PubMed

The content of various heavy metals (arsenic, cadmium, chromium, copper, iron, lead, mercury, nickel, manganese and zinc) in the moss species Rhodobryum ontariense (Kindb.) Kindb. and its tea are presented in this study. Pursuant to the use of this tea in traditional Chinese medicine for hypertension, the aim of this study was to examine its safety in regard to the metals. All heavy metals were determined by adequate EPA methods. The concentrations of all metals for daily intake in its tea were below the safety levels for human consumption. These results indicate the importance of manganese in R. ontariense tea traditionally used for hypertension and other heart disorders. PMID:22236074

Pejin, Boris; Kien-Thai, Yong; Stanimirovic, Bojana; Vuckovic, Gordana; Belic, Danijela; Sabovljevic, Marko

2012-01-01

162

Heavy metal removal using peat/wetland treatment  

SciTech Connect

The purpose of this paper is to present an overview of the mechanisms and application of a peat/wetland treatment system for heavy metal removal from wastewater. The mechanisms involved in the removal of heavy metals are complex and difficult to predict, however, peat has been proven to be an effective medium to remove metals. The successful design of a peat/wetland treatment system for acid mine drainage is presented to emphasize the low cost and minimal maintenance involved in this passive metal removal technique.

Murawski, S. [Univ. of Wisconsin, Milwaukee, WI (United States); [STS Consultants Ltd., Milwaukee, WI (United States)

1994-12-31

163

Industrial age anthropogenic inputs of heavy metals into the pedosphere  

NASA Astrophysics Data System (ADS)

Heavy metals have been increasingly released into our environment. We present here, for the first time, the global industrial age production of Cd, Cu, Cr, Hg, Ni, Pb, and Zn, and their potential accumulation and environmental effects in the pedosphere. World soils have been seriously polluted by Pb and Cd and slightly by Zn. The potential industrial age anthropogenic Pb, Hg, and Cd inputs in the pedosphere are 9.6, 6.1, and 5.2 times those in the lithosphere, respectively. The potential anthropogenic heavy metal inputs in the pedosphere increased tremendously after the 1950s, especially for Cr and Ni. In 2000, the cumulative industrial age anthropogenic global production of Cd, Cr, Cu, Hg, Ni, Pb, and Zn was 1.1, 105, 451, 0.64, 36, 235, and 354 million tonnes, respectively. The global industrial age metal burdens per capita (in 2000) were 0.18, 17.3, 74.2, 0.10, 5.9, 38.6, and 58.2 kg for Cd, Cr, Cu, Hg, Ni, Pb, and Zn, respectively. Acidification may increase the bioavailability and toxicity of heavy metals in the pedosphere. The improvement of industrial processing technology reducing the metal dispersion rate, the recycling of metal-containing outdated products, by-products and wastes, and the development of new substitute materials for heavy metals are possible strategies to minimize the effects of heavy metals on our environment.

Han, Fengxiang; Banin, Amos; Su, Yi; Monts, David; Plodinec, John; Kingery, William; Triplett, Glover

2002-10-01

164

Heavy Metals Removal Using Adsorption and Nanofiltration Techniques  

Microsoft Academic Search

The removal of some heavy metals Cu (II), Cd(II), Mn(II), Pb(II) As(III), and As(V) from water solution using absorption and nanofiltration membrane techniques is presented. The influence of temperature, sorbent mass, solution pH, flow rate and sorbent chemical modification in the adsorption process are discussed. Among the listed sorbents the best performers for higher initial heavy metal concentration are: montmorillonite,

Badriya Al-Rashdi; Chris Somerfield; Nidal Hilal

2011-01-01

165

Natural radionuclides and heavy metals in bottled water in Greece  

Microsoft Academic Search

Natural radionuclides and heavy metals in bottled waters of the major brands in Greece were measured. Gross alpha- and beta-activities were evaluated first; subsequently 226Ra was measured by alpha spectroscopy. Tritium and uranium activities were assessed with liquid scintillation counting. Heavy metals were determined by X-ray fluorescence spectroscopy following pre-concentration. A correlation of activity concentrations with the chemical parameters of

D. Karamanis; K. Stamoulis; K. G. Ioannides

2007-01-01

166

Heavy metal induced physiological alterations in Salvinia natans  

Microsoft Academic Search

Salvinia possess inherent capacity to accumulate high levels of various heavy metals. Accumulation of Cr, Fe, Ni, Cu, Pb and Cd ranged between 6 and 9mgg?1dry wt., while accumulation of Co, Zn and Mn was ?4mgg?1dry wt. Heavy metal accumulation affected the physiological status of plants. Photosystem II activity noted to decline in Ni, Co, Cd, Pb, Zn and Cu

Bhupinder Dhir; P. Sharmila; P. Pardha Saradhi; S. Sharma; R. Kumar; Devinder Mehta

2011-01-01

167

Heavy metal removal from sewage sludge ash analyzed by thermogravimetry  

Microsoft Academic Search

A high temperature (1000 °C) thermochemical process for heavy metal removal from sewage sludge ash via the chloride pathway\\u000a was investigated by thermogravimetry\\/differential thermal analysis (TG\\/DTA). TG and DTA measurements gave information about\\u000a secession and evaporation of water, HCl, and heavy metal chlorides at different temperatures. Additionally, gaseous water\\u000a and hydrochloric acid which occurred in the process were detected by an

Christian Vogel; Christian Adam; Miriam Unger

2011-01-01

168

Heavy metal pollution of ambient air in Nagpur City  

Microsoft Academic Search

Heavy metals released from different sources in urban environment get adsorbed on respirable particulate matter less than\\u000a 10 ?m in size (PM10) and are important from public health point of view causing morbidity and mortality. Therefore, the ambient air quality monitoring\\u000a was carried out to study the temporal and special pattern in the distribution of PM10 and associated heavy metal content

Pramod R. Chaudhari; Rakhi Gupta; Daulat Ghilagi Gajghate; Satish R. Wate

169

Pollution Regionalization of Soil Heavy Metals in County Scale  

Microsoft Academic Search

The main objective of this study was to make a pollution regionalization of soil heavy metals in A city, an area with rapid economic development in Yangtze River Delta of China. Therefore, the spatial distribution of soil heavy metals was firstly estimated by optimal space method using 126 data points and performed using ArcGIS9.2 software. The areas of different content

Zhou Shenglu; Zhang Hongfu; Wu Shaohua; Cao Wei; Qi Shusi

2010-01-01

170

Removal of heavy metals using the fungus Aspergillus niger  

Microsoft Academic Search

There is a need to develop technologies that can remove toxic heavy metal ions found in wastewaters. Microorganisms are known to remove heavy metal ions from water. In this study the potential of the fungus Aspergillus niger to remove lead, cadmium, copper and nickel ions was evaluated. A. niger biomass pretreated by boiling in 0.1N NaOH solution for 15 min

Anoop Kapoor; T Viraraghavan; D. Roy Cullimore

1999-01-01

171

PHYTOCHELATINS AND METALLOTHIONEINS: Roles in Heavy Metal Detoxification and Homeostasis  

Microsoft Academic Search

? Abstract Among,the heavy metal-binding ligands in plant cells the phytochelatins (PCs) and metallothioneins,(MTs) are the best characterized. PCs and MTs are different classes of cysteine-rich, heavy metal-binding protein molecules. PCs are enzymatically synthesized peptides, whereas MTs are gene-encoded polypeptides. Recently, genes encoding,the enzyme,PC synthase have been identified in plants and other species while the completion,of the Arabidopsis genome,sequence,has allowed

Christopher Cobbett; Peter Goldsbrough

2002-01-01

172

COMPARATIVE ASSESSMENT OF HEAVY METALS IN Euphorbia helioscopia L  

Microsoft Academic Search

In order to ascertain accumulation of heavy metals including Fe, Co, Ni, Cu, Cr, Mn, Cd and Pb in Euphorbia helioscopia L. found in polluted and unpolluted sites of Peshawar city, investigations were performed by using atomic absorption spectrometry. Comparative assessment of heavy metal contents confirmed accumulation of iron in leaves (67.00 mg kg-1) and stem (13.50 mg kg-1) followed

Shad Ali Khan; Lajbar Khan; Iqbal Hussain; Haider Shah; Naveed Akhtar

173

Heavy metal contamination of agricultural soil and countermeasures in Japan  

Microsoft Academic Search

Many heavy metals exist in minute amounts in natural agricultural soil. However, when their amounts exceed a certain level\\u000a due to pollutants brought from outside, soil contamination occurs and agricultural products become contaminated. There have\\u000a been many cases in Japan of heavy metal contamination originating from old mines and smelters, and soil contamination of agricultural\\u000a land has become a social

Tomohito Arao; Satoru Ishikawa; Masaharu Murakami; Kaoru Abe; Yuji Maejima; Tomoyuki Makino

2010-01-01

174

Heavy Metals Removal in a Horizontal Rotating Tubular Bioreactor  

Microsoft Academic Search

Mixed microbial culture was isolated from heavy metal-contaminated ground soils located inside iron, vinyl and cement factory\\u000a area. Isolated mixed microbial culture was used for the heavy metal ions (Fe2+, Cu2+, Ni2+ and Zn2+) removal process in horizontal rotating tubular bioreactor (HRTB). In this research, the effect of bioreactor process parameters\\u000a on the bioprocess dynamics in the HRTB was studied.

Ton?i Rezi?; Michaela Zeiner; Božidar Šantek; Sr?an Novak

2011-01-01

175

Heavy metals in sediments from constructed wetlands treating municipal wastewater  

Microsoft Academic Search

Constructed wetlands are commonly used for treatment of municipal sewage. The treatment is usually aimed at removal of organics,\\u000a suspended solids, nutrients and microbial pollution. The information on removal and fate of heavy metals is very limited.\\u000a The purpose of this study was to evaluate the amount of sediments and heavy metal concentration in the sediments in filtration\\u000a beds of

Jan Vymazal; Jaroslav Švehla; Lenka Kröpfelová; Jana N?mcová; Vladimír Suchý

2010-01-01

176

A review of heavy metal adsorption by marine algae  

Microsoft Academic Search

Accumulation of heavy metals by algae had been studied extensively for biomonitoring or bioremediation purposes. Having the\\u000a advantages of low cost raw material, big adsorbing capacity, no secondary pollution, etc., algae may be used to treat industrial\\u000a water containing heavy metals. The adsorption processes were carried out in two steps: rapid physical adsorption first, and\\u000a then slow chemical adsorption. pH

Jin-Fen Pan; Rong-Gen Lin; Li Ma

2000-01-01

177

Phytoremediation for heavy metal?contaminated soils combined with bioenergy production  

Microsoft Academic Search

In June 2007, a project started in Flanders (Belgium) in which we will apply phytoremediation to clean soils that are diffusely polluted with heavy metals. Uptake ranges of heavy metals by rape seed, maize and wheat will be enhanced by increasing the bioavailability of these heavy metals by the addition of biodegradable physico?chemical agents and by stimulating the heavy?metal uptake

Luc Van Ginneken; Erik Meers; Ruben Guisson; Ann Ruttens; Kathy Elst; Filip M. G. Tack; Jaco Vangronsveld; Ludo Diels; Winnie Dejonghe

2007-01-01

178

Content of some heavy metals in soil and corn grain  

SciTech Connect

In an attempt to find causes for lower than expected corn (Zea mays L.) production along the bottomlands of the Green and Pond Rivers in western Kentucky, corn fields were sampled for soil and corn grain to determine heavy metal content. Samples from sixteen carefully selected fields were analyzed for Cd, Cr, Pb, and Ni content. Yield of corn was not related to either soil or grain content of these heavy metals. There was also not relationship between soil pH and heavy metal accumulation by grain or heavy metal accumulation by grain and soil and Ni were within the range of values reported in the literature for uncontaminated soils. However, soil content of Cd was near or above the upper end of the ranges reported in the literature, even on control samples taken upstream from sites of potential heavy metal pollution. Karnak soils (fine, montmorillonitic, nonacid, mesic Vertic Haplaquepts), which are high in montmorillonitic clay content and have high cation exchange capacities, had higher Cd content than the other soils sampled. Except for two sites, grain Cd content was similar to values reported in the literature. Corn yields were found to be generally lower on Karnak soils than on other soils, raising the possibility that observed lower than expected yields are related to the poor physical characteristics of these soils rather than heavy metal pollutants in floodwaters. 8 refs., 1 fig., 6 tabs.

Wells, K.L. (Univ. of Kentucky, Lexington (United States)); Henson, G.; Kelley, G. (McLean and Hopkins Counties, KY (United States))

1993-01-01

179

Evaluation of electrokinetic removal of heavy metals from sewage sludge.  

PubMed

The presence of heavy metals is one of the main obstacles for agricultural use of million tonnes of dewatered sewage sludge produced in wastewater treatment plants. Electrokinetic (EK) treatment can be applied to remove heavy metals from sludge. The aim of this study was to increase the efficiency of electrokinetic removal of heavy metals from dewatered sewage sludge. EK experiments were carried out with and without pH adjustment in cathode chamber of acidified sewage sludge. The selective sequential extraction (SSE) was used to determine the fractionation of heavy metals in sewage sludge. The mobility of heavy metals in sludge significantly increased after its acidification at pH 2.7 and followed the order: Ni, Zn, Cu, As, Cr, Pb. Removal efficiencies of heavy metals in the experiment with acidified sewage sludge and pH adjustment at cathode chamber at 2.0 were: 95% for Zn, 96% for Cu, 90% for Ni, 68% for Cr, 31% for As and 19% for Pb. The concentrations of Zn, Cu, Ni, Cr and Pb after EK treatment were below the United States Environmental Protection Agency limits for biosolids applied to agricultural land, forest, public contact sites or reclamation sites. PMID:15994006

Wang, Jing-Yuan; Zhang, Di-Song; Stabnikova, Olena; Tay, Joo-Hwa

2005-09-30

180

Heavy metal ions are potent inhibitors of protein folding  

SciTech Connect

Environmental and occupational exposure to heavy metals such as cadmium, mercury and lead results in severe health hazards including prenatal and developmental defects. The deleterious effects of heavy metal ions have hitherto been attributed to their interactions with specific, particularly susceptible native proteins. Here, we report an as yet undescribed mode of heavy metal toxicity. Cd{sup 2+}, Hg{sup 2+} and Pb{sup 2+} proved to inhibit very efficiently the spontaneous refolding of chemically denatured proteins by forming high-affinity multidentate complexes with thiol and other functional groups (IC{sub 50} in the nanomolar range). With similar efficacy, the heavy metal ions inhibited the chaperone-assisted refolding of chemically denatured and heat-denatured proteins. Thus, the toxic effects of heavy metal ions may result as well from their interaction with the more readily accessible functional groups of proteins in nascent and other non-native form. The toxic scope of heavy metals seems to be substantially larger than assumed so far.

Sharma, Sandeep K. [Biochemisches Institut, Universitaet Zuerich, CH-8057 Zuerich (Switzerland); Departement de Biologie Moleculaire Vegetale, Universite de Lausanne, CH-1015 Lausanne (Switzerland); Goloubinoff, Pierre [Departement de Biologie Moleculaire Vegetale, Universite de Lausanne, CH-1015 Lausanne (Switzerland); Christen, Philipp [Biochemisches Institut, Universitaet Zuerich, CH-8057 Zuerich (Switzerland)], E-mail: christen@bioc.uzh.ch

2008-07-25

181

Effects of heavy metals on insect immunocompetent cells.  

PubMed

The influence of the following heavy metals, copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb), on haemocytes of the house fly Musca domestica L. was studied under laboratory conditions. House fly larvae were exposed to low or high, semi-lethal concentrations of metals. These particular metals were selected because they are present in polluted environments in Poland. In addition, we studied expression of the stress proteins HSP70 and HSP72 in haemocytes collected from larvae that had been exposed to heavy metal. The obtained results showed changes in haemocytes morphology and phagocytotic plasticity in the experimental flies in comparison to control. The number of prohaemocytes, regarded as stem cells, increased, while granulocytes, responsible for phagocytosis, decreased. However, we have not detected any clear changes in expression of HSP70 or HSP72 in flies treated with low or high concentrations of the heavy metals. PMID:21419130

Borowska, Joanna; Pyza, El?bieta

2011-06-01

182

Biosurfactant of marine origin exhibiting heavy metal remediation properties.  

PubMed

The present study was aimed at elucidating the role of biosurfactant product isolated from a marine bacterium in removing heavy metals from heavy metal containing solutions. In this study, metal removal was biosurfactant-mediated. Efficiency of metal removal depended on the concentration of the metal as well as that of the biosurfactant. At a concentration 5x, the critical micelle concentration (CMC), almost complete removal of 100 ppm of lead and cadmium occurred. Atomic absorption spectroscopy (AAS) studies also showed metal removal at a concentration less than the CMC in contrast to earlier findings that only micelles are involved in metal removal. Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) equipped with energy dispersive X-ray spectroscopy (EDS) further substantiated these findings. PMID:19505818

Das, Palashpriya; Mukherjee, Soumen; Sen, Ramkrishna

2009-10-01

183

Effect of ultrasonic treatment on heavy metal decontamination in milk.  

PubMed

Ultrasound has been found useful in increasing the efficiency and consumer safety in food processing. Removal of heavy metal (lead, mercury, and arsenic) contamination in milk is extremely important in regions of poor ecological environment - urban areas with heavy motor traffic or well established metallurgical/cement industry. In this communication, we report on the preliminary studies on the application of low frequency (20kHz) ultrasound for heavy metal decontamination of milk without affecting its physical, chemical, and microbiological properties. PMID:24746508

Porova, Nataliya; Botvinnikova, Valentina; Krasulya, Olga; Cherepanov, Pavel; Potoroko, Irina

2014-11-01

184

[Carbonization of heavy metal Cu implanted sewage sludge and stability of heavy metal in the resulting char].  

PubMed

In this research, a new method for sewage sludge (SS) disposal was introduced, by which heavy metals were implanted into sewage sludge before pyrolysis. Cu was adopted as the representative of heavy metals to test this process and was implanted in the form of CuCl2. Effects of Cu implanting concentration and reaction temperature on the residual ratio and immobilization of heavy metals in pyrolysis char were studied. Meanwhile, two leaching methods were employed with the purpose to determine the maximum capacity of heavy metal immobilization in the char. The primary research results showed that when the Cu implanting concentration was 0.5% (mass fraction), more than 90% of Cu remained in the char after carbonization, and the leachability of heavy metals in the char was related to pyrolysis temperature. Cu leaching from the char increased with increasing pyrolysis temperature. There was also a limitation for Cu implanting concentration in the sewage sludge, which was determined by the destination of the pyrolyzed char. If it went to sanitary landfill, the limitation would be 0.5%. The primary results showed that sewage sludge could be kneaded with other wastes containing heavy metals before pyrolysis to achieve co-processing. PMID:25639117

Dou, Xiao-Min; Chen, De-Zhen; Dai, Xiao-Hu

2014-11-01

185

Endophytic bacteria and their potential to enhance heavy metal phytoextraction  

Microsoft Academic Search

Pollution of soils with heavy metals is becoming one of the most severe environmental and human health hazards. Due to its widespread contamination finding innovative ways to clean metal pollutant has become a priority in the remediation field. Phytoremediation, the use of plants for the restoration of environments contaminated with pollutants is a relatively new technology that is more benign

Mani Rajkumar; Noriharu Ae; Helena Freitas

2009-01-01

186

COUPLED TRANSPORT SYSTEMS FOR CONTROL OF HEAVY METAL POLLUTANTS  

EPA Science Inventory

This report describes a process for separating and concentrating heavy metals from electroplating rinse waters. Metal ions can be 'chemically pumped' across a coupled transport membrane against large concentration gradients by allowing the counterflow of a coupled ion such as hyd...

187

SOIL MICROBIAL EFFECTS ON HEAVY METAL UPTAKE INTO HYPERACCUMULATORS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Uptake of heavy metals into hyperaccumulators is influenced by a number of chemical, physical and biological factors. Of these, recent evidence has shown that microbes living within the rhizosphere of hyperaccumulators may have a significant effect on metal uptake. Much is known about the role my...

188

Heavy metal concentrations along the Louisiana coastal zone  

Microsoft Academic Search

Cores were taken from seven locations in southern Louisiana and analyzed for concentrations of heavy metals. Sedimentation rates for the locations were determined using the ¹³⁷Cs dating technique. Correlations of metals with depth were calculated using absolute, aluminum normalized, and iron normalized concentrations. Correlations indicated recent increases at several sites (Lake Palourde, Manchac Pass, and Wax Lake Outlet) for several

J. H. Pardue; R. D. DeLaune; C. J. Smith; W. H. Jr. Patrick

1988-01-01

189

The electric field gradient in heavy rare earth metals  

Microsoft Academic Search

Estimates of the electric field gradient in heavy rare earth metals have been evaluated from experimental hyperfine interaction data. In addition, the magnetic hyperfine fields are analyzed. In the metals the effective radial integrals r-3>4f of the magnetic and quadrupole hyperfine interaction are reduced at most by 10% compared with the free ion values. The electric field gradients due to

J. Pelzl; Fachbereich Physik

1972-01-01

190

Geochemical Assessment of Heavy Metals Pollution of Urban Soils  

Microsoft Academic Search

Metals associated with urban soils are of environmental concern because of their direct and indirect effects on human health. The main purposes of this study undertaken in the city of Poznan (Poland) were to identify heavy metals with dangerous environmental load and to define areas of their environmental impact. Measured concentrations of cadmium, lead, copper and zinc in surface horizon

W. Grzebisz; L. Cie?la; J. Komisarek; J. Potarzycki

191

Molecular mechanisms of heavy metal hyperaccumulation and phytoremediation  

Microsoft Academic Search

A relatively small group of hyperaccumulator plants is capable of sequestering heavy metals in their shoot tissues at high concentrations. In recent years, major scientific progress has been made in understanding the physiological mechanisms of metal uptake and transport in these plants. However, relatively little is known about the molecular bases of hyperaccumulation. In this paper, current progresses on understanding

Xiaoe Yang; Ying Feng; Zhenli He; Peter J. Stoffella

2005-01-01

192

Heavy metals in mangroves: methodology, monitoring and management  

Microsoft Academic Search

Mangroves occur widely throughout Australia and, at some sites, are exposed to elevated heavy metal loads. The value of mangrove communities, and particularly of mangrove forest sediments, as a buffer between potential sources of metalliferous pollutants and marine ecosystems has been noted previously (Harbison, 1981, 1986; Saenger et al., 1991). How mangroves respond to the metal load in their environment

Peter Saenger; David McConchie

2004-01-01

193

Heavy Metals Competing with Iron under Conditions Involving Phytoremediation  

Microsoft Academic Search

Heavy metals polluting the environment influence adsorption, uptake and translocation of iron in plants. Toxic metals are usually retained in the roots and there is little accumulation in the shoot, and plants suffer from different levels of stress due in many occasions to insufficient iron supply. However, there are certain plant species or varieties that can accumulate over a thousand

Ferenc Fodor

194

Analysis of heavy metals in road-deposited sediments.  

PubMed

Road-deposited sediments were analysed for heavy metal concentrations at three different landuses (residential, industrial, commercial) in Queensland State, Australia. The sediments were collected using a domestic vacuum cleaner which was proven to be highly efficient in collecting sub-micron particles. Five particle sizes were analysed separately for eight heavy metal elements (Zn, Fe, Pb, Cd, Cu, Cr, Al and Mn). At all sites, the maximum concentration of the heavy metals occurred in the 0.45-75 microm particle size range, which conventional street cleaning services do not remove efficiently. Multicriteria decision making methods (MCDM), PROMETHEE and GAIA, were employed in the data analysis. PROMETHEE, a non-parametric ranking analysis procedure, was used to rank the metal contents of the sediments sampled at each site. The most polluted site and particle size range were the industrial site and the 0.45-75 microm range, respectively. Although the industrial site displayed the highest metal concentrations, the highest heavy metal loading coincided with the highest sediment load, which occurred at the commercial site. GAIA, a special form of principal component analysis, was applied to determine correlations between the heavy metals and particle size ranges and also to assess possible correlation with total organic carbon (TOC). The GAIA-planes revealed that irrespective of the site, most of the heavy metals are adsorbed to sediments below 150 microm. A weak correlation was found between Zn, Mn and TOC at the commercial site. This could lead to higher bioavailability of these metals through complexation reactions with the organic species in the sediments. PMID:17723448

Herngren, Lars; Goonetilleke, Ashantha; Ayoko, Godwin A

2006-07-01

195

Magnetic process for removing heavy metals from water employing magnetites  

DOEpatents

A process for removing heavy metals from water is provided. The process includes the steps of introducing magnetite to a quantity of water containing heavy metal. The magnetite is mixed with the water such that at least a portion of, and preferably the majority of, the heavy metal in the water is bound to the magnetite. Once this occurs the magnetite and absorbed metal is removed from the water by application of a magnetic field. In most applications the process is achieved by flowing the water through a solid magnetized matrix, such as steel wool, such that the magnetite magnetically binds to the solid matrix. The magnetized matrix preferably has remnant magnetism, but may also be subject to an externally applied magnetic field. Once the magnetite and associated heavy metal is bound to the matrix, it can be removed and disposed of, such as by reverse water or air and water flow through the matrix. The magnetite may be formed in-situ by the addition of the necessary quantities of Fe(II) and Fe(III) ions, or pre-formed magnetite may be added, or a combination of seed and in-situ formation may be used. The invention also relates to an apparatus for performing the removal of heavy metals from water using the process outlined above.

Prenger, F. Coyne; Hill, Dallas D.; Padilla, Dennis D.; Wingo, Robert M.; Worl, Laura A.; Johnson, Michael D.

2003-07-22

196

Magnetic process for removing heavy metals from water employing magnetites  

DOEpatents

A process for removing heavy metals from water is provided. The process includes the steps of introducing magnetite to a quantity of water containing heavy metal. The magnetite is mixed with the water such that at least a portion of, and preferably the majority of, the heavy metal in the water is bound to the magnetite. Once this occurs the magnetite and absorbed metal is removed from the water by application of a magnetic field. In most applications the process is achieved by flowing the water through a solid magnetized matrix, such as steel wool, such that the magnetite magnetically binds to the solid matrix. The magnetized matrix preferably has remnant magnetism, but may also be subject to an externally applied magnetic field. Once the magnetite and associated heavy metal is bound to the matrix, it can be removed and disposed of, such as by reverse water or air and water flow through the matrix. The magnetite may be formed in-situ by the addition of the necessary quantities of Fe(II) and Fe(III) ions, or pre-formed magnetite may be added, or a combination of seed and in-situ formation may be used. The invention also relates to an apparatus for performing the removal of heavy metals from water using the process outlined above.

Prenger, F. Coyne; Hill, Dallas D.

2006-12-26

197

Heavy metals removal from automobile shredder residues (ASR).  

PubMed

The fate of heavy metals during a separation process for automobile shredder residues (ASR) was investigated. A washing method to remove heavy metals from the ASR was also investigated. Although the separation process was not designed for removal of heavy metals, but for the recovery of reusable materials, the heavy metal content in the ASR was efficiently decreased. The concentrations of Pb, Cr and Cd in ASR were effectively reduced by a nonferrous metals removal process, and the As concentration was reduced by the removal of light dusts during the separation process. Five heavy metals (As, Se, Pb, Cr, Cd) remaining in the ASR after the separation process satisfied the content criteria of the Environmental Quality Standards for Soil (EQSS), while the concentrations of As, Se, Pb in the leachate from the remaining ASR did not satisfy the elution criteria of the EQSS. After additional washing of the remaining ASR with a pH 1 acid buffer solution, the As, Se, and Pb concentrations satisfied the EQSS for elution. These results indicate that an ASR residue can be safely recycled after a separation process, followed by washing at acidic pH. PMID:16797833

Kurose, Keisuke; Okuda, Tetsuji; Nishijima, Wataru; Okada, Mitsumasa

2006-10-11

198

Screening Capsicum chinense fruits for heavy metals bioaccumulation.  

PubMed

Elevated concentrations of heavy metals in edible plants could expose consumers to excessive levels of potentially hazardous chemicals. Sixty-three accessions (genotypes) of Capsicum chinense Jacq, collected from 8 countries of origin were grown in a silty-loam soil under field conditions. At maturity, fruits were collected and analyzed for seven heavy metals (Cd, Cr, Ni, Pb, Zn, Cu, and Mo) concentrations. The main objectives of this investigation were: 1) to determine the concentrations of seven heavy metals in the soil and monitor their accumulation in mature fruits, 2) to categorize the pepper accessions as low or high heavy metal accumulators, and 3) to determine if heavy metal content of the pepper fruit was lower than the permitted limits. Concentrations and relative proportions of heavy metals in pepper fruits of C. chinense varied among accessions. Fruits of Plant Introduction (PI) 355820 accumulated significant concentrations of Cd (0.47 ?g g(-1) dry fruit). PI-260522 accumulated the highest concentration of Pb (2.12 ?g g(-1) dry fruit) among the 63 accessions tested. This accession (PI-260522) contained about twice the Pb limit on a fresh weight basis. Among the 63 accessions analyzed, PI-238051 contained the highest levels of Ni (17.2 ?g g(-1)). We concluded that high accumulator genotypes may be useful for phytoremediation, while, low accumulator accessions might be appropriate selections for growing on Cd-, Pb-, or Ni-contaminated soils to prevent potential human exposure to heavy metals and health hazards through the food chain. PMID:20635296

Antonious, George F; Snyder, John C; Berke, Terry; Jarret, Robert L

2010-08-01

199

Molecular Indicators of Soil Humification and Interaction with Heavy Metals  

SciTech Connect

For stabilization of heavy metals at contaminated sites, interaction of soil organic matter (SOM) with heavy metal ions is critically important for long-term sustainability, a factor that is poorly understood at the molecular level. Using 13C- and 15N-labeled soil humates (HS), we investigated the turnover of five organic amendments (celluose, wheat straw, pine shavings, chitin and bone meal) in relation to heavy metal ion leaching in soil column experiments. The labeled molecular substructures in HS were examined by multinuclear 2-D NMR and pyrolysis GC-MS while the element profile in the leachates was analyzed by ICP-MS. Preliminary analysis revealed that peptidic and polysaccharidic structures were highly enriched, which suggests their microbial origin. Cd(II) leaching was significantly attenuated with humification of lignocellulosic materials. Correlation of 13C and 15N turnovers of HS substructures to metal leaching is underway.

Fan, Teresa W.-M.; Higashi, Richard M.; Cassel, Teresa; Green, Peter; Lane, Andrew N.

2003-03-26

200

The effect of plant cadmium and zinc status on root and shoot heavy metal accumulation in the heavy metal hyperaccumulator, Thlaspi caerulescens  

Technology Transfer Automated Retrieval System (TEKTRAN)

Thlaspi caerulescens is a plant species capable of tolerating and accumulating extremely high concentrations of the heavy metals, Zn and Cd, in the shoot. In this study, we investigated the impact of changes in plant heavy metal status (i.e. Zn and Cd) on the accumulation of heavy metals, including...

201

Chemical precipitation of heavy metals from acid mine drainage  

Microsoft Academic Search

The 1,3-benzenediamidoethanethiol dianion (BDET, known commercially as MetX) has been developed to selectively and irreversibly bind soft heavy metals from aqueous solution. In the present study BDET was found to remove >90% of several toxic or problematic metals from AMD samples taken from an abandoned mine in Pikeville, Kentucky. The concentrations of metals such as iron, may be reduced at

Matthew M Matlock; Brock S Howerton; David A Atwood

2002-01-01

202

Perspectives in endocrine toxicity of heavy metals--a review.  

PubMed

An attempt has been made to review the endocrine/hormonal implications of a few environmentally significant metals, viz, lead, mercury, cadmium, copper, arsenic and nickel, in man and animals. Special emphasis has been given to the adrenals, thyroid, testis, ovary and pancreas. Toxic metals can cause structural and functional changes in the adrenal glands. Their effects on steroidogenesis have been reviewed. It has been reported that thyroid hormone kinetics are affected by a number of metallic compounds. Occupational exposure to a few of these metals can cause testicular injury and sex hormone disturbances. Protective effects of a few antioxidants on their reproductive toxicity have also been discussed. Information gathered on female reproductive toxicity of heavy metals shows that exposure to these metals can lead to disturbances in reproductive performance in exposed subjects. Certain metals can cause injury to the endocrine pancreas. Exposure to them can cause diabetes mellitus and disturb insulin homeostasis. The need to develop molecular markers of endocrine toxicity of heavy metals has been suggested. Overall information described in this review is expected to be helpful in planning future studies on endocrine toxicity of heavy metals. PMID:24898714

Rana, S V S

2014-07-01

203

Source of atmospheric heavy metals in winter in Foshan, China.  

PubMed

Foshan is a ceramics manufacturing center in the world and the most polluted city in the Pearl River Delta (PRD) in southern China measured by the levels of atmospheric heavy metals. PM2.5 samples were collected in Foshan in winter 2008. Among the 22 elements and ions analyzed, 7 heavy metals (Zn, V, Mn, Cu, As, Cd and Pb) were studied in depth for their levels, spatiotemporal variations and sources. The ambient concentrations of the heavy metals were much higher than the reported average concentrations in China. The levels of Pb (675.7 ± 378.5 ng/m(3)), As (76.6 ± 49.1 ng/m(3)) and Cd (42.6 ± 45.2 ng/m(3)) exceeded the reference values of NAAQS (GB3095-2012) and the health guidelines of the World Health Organization. Generally, the levels of atmospheric heavy metals showed spatial distribution as: downtown site (CC, Chancheng District)>urban sites (NH and SD, Nanhai and Shunde Districts)>rural site (SS, Shanshui District). Two sources of heavy metals, the ceramic and aluminum industries, were identified during the sampling period. The large number of ceramic manufactures was responsible for the high levels of atmospheric Zn, Pb and As in Chancheng District. Transport from an aluminum industry park under light north-west winds contributed high levels of Cd to the SS site (Shanshui District). The average concentration of Cd under north-west wind was 220 ng/m(3), 20.5 times higher than those under other wind directions. The high daily maximum enrichment factors (EFs) of Cd, Pb, Zn, As and Cu at all four sites indicated extremely high contamination by local emissions. Back trajectory analysis showed that the heavy metals were also closely associated with the pathway of air mass. A positive matrix factorization (PMF) method was applied to determine the source apportionment of these heavy metals. Five factors (industry including the ceramic industry and coal combustion, vehicle emissions, dust, transportation and sea salt) were identified and industry was the most important source of atmospheric heavy metals. The present paper suggests a control policy on the four heavy metals Cd, Pb, Zn, and Cu, and suggests the inclusion of As in the ceramic industry emission standard in the future. PMID:24951884

Tan, Ji-Hua; Duan, Jing-Chun; Ma, Yong-Liang; Yang, Fu-Mo; Cheng, Yuan; He, Ke-Bin; Yu, Yong-Chang; Wang, Jie-Wen

2014-09-15

204

Implications of soil pollution with heavy metals for public health  

NASA Astrophysics Data System (ADS)

Soil of military grounds is often polluted with heavy metals. Their concentrations may be dosens of times higher in polluted regions. The affected soils are permeable, so the pollutions can get into water and spread to the environment. Into human and animal organisms they can get with food and water. Heavy metals are very dangerous for people's health, and we must know their accumulation places, intensity of scatter and integral risk for health. The purpose of this work was to establish links between zones polluted with heavy metals and morbidity caused by pollution with heavy metals. The morbidity caused by heavy metals (Pb, Cu, Zn, Ca and other) in the polluted regions is 1.4-1.5 times higher for adults and teenagers and 1.5-3.9 times higher for children aged under 14 years than the mean morbidity of the same diseases in Lithuania. Hypothetically, it is possible to prognosticate that this problem will grow in future because the ratio of the newly registered and the existing cases of morbidity for children aged under 14 years is 1.3-1.5 times higher than for adults.

Juozulynas, Algirdas; Jurgel?nas, Antanas; Butkien?, Birut?; Grei?i?t?, Kristina; Savi?i?t?, Rasa

2008-01-01

205

Effect of heavy metals on germination of seeds.  

PubMed

With the expansion of the world population, the environmental pollution and toxicity by chemicals raises concern. Rapid industrialization and urbanization processes has led to the incorporation of pollutants such as pesticides, petroleum products, acids and heavy metals in the natural resources like soil, water and air thus degrading not only the quality of the environment, but also affecting both plants and animals. Heavy metals including lead, nickel, cadmium, copper, cobalt, chromium and mercury are important environmental pollutants that cause toxic effects to plants; thus, lessening productivity and posing dangerous threats to the agro-ecosystems. They act as stress to plants and affect the plant physiology. In this review, we have summarized the effects of heavy metals on seeds of different plants affecting the germination process. Although reports exist on mechanisms by which the heavy metals act as stress and how plants have learnt to overcome, the future scope of this review remains in excavating the signaling mechanisms in germinating seeds in response to heavy metal stress. PMID:24082715

Sethy, Sunil Kumar; Ghosh, Shyamasree

2013-07-01

206

Cocoa shells for heavy metal removal from acidic solutions.  

PubMed

The development of economic and efficient processes for the removal of heavy metals present in acidic effluents from industrial sources or decontamination technologies has become a priority. The purpose of this work was to study the efficiency with which cocoa shells remove heavy metals from acidic solutions (pH 2) and to investigate how the composition of these solutions influences heavy metal uptake efficiency. Adsorption tests were conducted in agitated flasks with single-metal solutions (0.25 mM Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn), multi-metal solution (comprised of 0.25 mM of each of the cations above) and an effluent obtained from chemical leaching of metal-contaminated soil, in the presence of different cocoa shell concentrations (5-40 g/l). Results from the single-metal solution assays indicated that the fixation capacity of heavy metals by cocoa shells followed a specific order: Pb>Cr>Cd=Cu=Fe>Zn=Co>Mn=Ni=Al. Cocoa shells are particularly efficient in the removal of lead from very acidic solutions (q(max)=6.2 mg Pb/g, pH(i)=2.0 and T=22 degrees C). The presence of other metals and cations in solution did not seem to affect the recovery of lead. It was also observed that the maximum metal uptake was reached in less than 2 h. This research has also demonstrated that the removal of metals caused a decline in solution proton concentration (pH increase) and release of calcium, magnesium, potassium and sodium from the cocoa shells. PMID:14575948

Meunier, N; Laroulandie, J; Blais, J F; Tyagi, R D

2003-12-01

207

Heavy metal mobility in biosolids-amended glaciated soils.  

PubMed

The mobility of heavy metals from one-time application of biosolids (i.e., compost, pellet, and cement kiln dust stabilized biosolids) onto glaciated soils (Paxton soil) was studied because previous work on metal leachate characteristics from different biosolids is limited for glaciated soils. Two types of batch tests were performed: first, a pH-edge adsorption study to evaluate the effect of pH on heavy metal adsorption to Paxton soil and, second, a pH-edge leaching study to evaluate the effect of pH on the leaching potential of heavy metals from biosolids-amended Paxton soil. Finally, a semicontinuous soil column study was performed to assess the mobility of heavy metals from biosolids-amended Paxton soil. The pH-edge leaching results showed that the leaching potential of heavy metals was lower with the compost product. Desorption concentrations for arsenic, chromium, and lead were found to be greatest in the cement kiln dust stabilized product whereas cadmium, copper, and nickel were present at the greatest concentrations in the pellets. The total organic carbon results measured during the pH-edge leaching study indicated that there is a minimum leachable concentration in the pH range of 4 to 5 for all three biosolids. Overall, the column studies indicated that heavy metals were not readily leached from the three biosolids-amended Paxton soils. The results from this study suggest that a one-time land application of these biosolids will not adversely affect groundwater quality. PMID:11558307

Nikolaidis, N P; Chheda, P

2001-01-01

208

Sorption of heavy metal ions on new metal-ligand complexes chemically derived from Lycopodium clavatum  

SciTech Connect

Sorption of heavy metal ions from aqueous solution has been investigated as a function of pH using a novel exchanger system whereby Lycopodium clavatum is functionalized with carboxylate and glyoxime metal-ligand complexes. The new ligand exchangers were prepared using a reaction of diaminosporopollenin with various metal-ligand complexes of glyoxime and monocarboxylic acid. The sorptive behavior of these metal-ligand exchangers and the possibilities to remove and to recover selectively heavy metal cations using these systems are discussed on the basis of their chemical natures and their complexing properties.

Pehlivan, E.; Ersoz, M.; Yildiz, S. [Univ. of Selcuk, Konya (Turkey); Duncan, H.J. [Univ. of Glasgow, Scotland (United Kingdom)

1994-08-01

209

Coupling bioleaching and electrokinetics to remediate heavy metal contaminated soils.  

PubMed

In this study, bioleaching was coupled with electrokinetics (BE) to remove heavy metals (Cu, Zn, Cr and Pb) from contaminated soil. For comparison, bioleaching (BL), electrokinetics (EK), and the chemical extraction method were also applied alone to remove the metals. The results showed that the BE method removed more heavy metals from the contaminated soil than the BL method or the EK method alone. The BE method was able to achieve metal solubilization rates of more than 70 % for Cu, Zn and Cr and of more than 40 % for Pb. Within the range of low current densities (<1 mA cm(-2)), higher current density led to more metal removal. However, the metal solubilization rates did not increase with increasing current density when the current density was higher than 1 mA cm(-2). Therefore, it is suggested that bioleaching coupled with electrokinetics can effectively remediate heavy metal-contaminated soils and that preliminary tests should be conducted before field operation to detect the lowest current density for the greatest metal removal. PMID:25680933

Huang, Qingyun; Yu, Zhen; Pang, Ya; Wang, Yueqiang; Cai, Zhihong

2015-04-01

210

Beneficial effect of sesame oil on heavy metal toxicity.  

PubMed

Heavy metals become toxic when they are not metabolized by the body and accumulate in the soft tissue. Chelation therapy is mainly for the management of heavy metal-induced toxicity; however, it usually causes adverse effects or completely blocks the vital function of the particular metal chelated. Much attention has been paid to the development of chelating agents from natural sources to counteract lead- and iron-induced hepatic and renal damage. Sesame oil (a natural edible oil) and sesamol (an active antioxidant) are potently beneficial for treating lead- and iron-induced hepatic and renal toxicity and have no adverse effects. Sesame oil and sesamol significantly inhibit iron-induced lipid peroxidation by inhibiting the xanthine oxidase, nitric oxide, superoxide anion, and hydroxyl radical generation. In addition, sesame oil is a potent inhibitor of proinflammatory mediators, and it attenuates lead-induced hepatic damage by inhibiting nitric oxide, tumor necrosis factor-?, and interleukin-1? levels. Because metal chelating therapy is associated with adverse effects, treating heavy metal toxicity in addition with sesame oil and sesamol may be better alternatives. This review deals with the possible use and beneficial effects of sesame oil and sesamol during heavy metal toxicity treatment. PMID:23744838

Chandrasekaran, Victor Raj Mohan; Hsu, Dur-Zong; Liu, Ming-Yie

2014-02-01

211

Metal-binding proteins and peptides in bioremediation and phytoremediation of heavy metals  

Microsoft Academic Search

The expression of metal-binding proteins or peptides in microorganisms and plants in order to enhance heavy metal accumulation and\\/or tolerance has great potential. Several different peptides and proteins have been explored. This review focuses on cadmium (Cd) because of the significant importance of this metal and because of its global presence in many food materials.

Malin Mejáre; Leif Bülow

2001-01-01

212

Heavy metal pollution in Japanese seabirds.  

PubMed

It is reported that seabirds accumulate high levels of metals, prompting concerns regarding poisoning. The present study investigated the accumulation patterns of metals in tissues among four species of seabirds (Fratercula corniculata, Uria lomvia, Puffinus tenuirostris, and Fulmarus glacialis). Furthermore, we focused on Slaty-backed Gulls, which accumulated high levels of cadmium and mercury, and compared the areal differences. Geographic variation of metal levels could also contribute to differences in metal accumulation levels in these bird species. Therefore, the concentrations of metals in seabirds are considered to reflect their habitat. There are differences in the accumulation pattern among the seabird species. The high accumulation of metals could affect seabirds even if they do not show any symptoms. PMID:23631160

Ishii, Chihiro; Ikenaka, Yoshinori; Nakayama, Shouta M M; Suzuki, Yuya; Watanuki, Yutaka; Watanabe, Yuji; Fukuwaka, Masa-aki; Yohannes, Yared B; Kawai, Yusuke K; Ishizuka, Mayumi

2013-02-01

213

Baker's yeast assay procedure for testing heavy metal toxicity  

SciTech Connect

Baker's yeast (Saccharomyces cerevisiae) is microorganism which is commercially available and sold as packaged dry pellets in any food store at low cost. Studies have been undertaken on the effects of organic xenobiotics as well as heavy metals on yeast metabolism. This type of study has been generally useful in examining the mechanism(s) of chemical toxicity. However, a rapid and quantitative toxicity test using S. cerevisiae as the test organism has not been developed. The purpose of this study was to develop a toxicity assay for heavy metals, using commercial dry yeast as the test microorganism. This rapid and simple procedure is based on the reduction of 2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyltetrazolium chloride (INT) to INT-formazan by the yeast electron transport system. The scoring of active cells following exposure to heavy metals was undertaken according to the MINT (malachite green-INT) method developed by Bitton and Koopman.

Bitton, G.; Koopman, B.; Wang, H.D.

1984-01-01

214

Trace organic and heavy metal pollutants in the Mississippi River  

SciTech Connect

A study was conducted to characterize and measure organic and heavy metal pollutants in the Mississippi River. Water samples were collected along the entire length of the river, and were screened for semivolatile organics by capillary GC and for heavy metals by atomic absorption spectrophotometry. Four water samples were further examined for semivolatile organics by capillary GC/MS. Eight heavy metals and more than sixty distinct organic chemicals were identified including alkylbenzenes, various halogenated organics, five herbicides or derivates, plasticizers, polynuclear aromatic hydrocarbons (PAHs), saturated hydrocarbons, and three miscellaneous organics. All organic compounds were detected at the parts-per-trillion (pptr) level. In spite of the limited nature of the sampling effort, the large number of data derived from this study suggests the need for a more rigorous monitoring of the river for a wide spectrum of chemical pollutants.

DeLeon, I.R.; Byrne, C.J.; Peuler, E.A.; Antoine, S.R.; Schaeffer, J.; Murphy, R.C.

1986-01-01

215

Heavy metal pollution disturbs immune response in wild ant populations.  

PubMed

Concern about the effects of environmental contaminants on immune function in both humans and wildlife is growing and practically nothing is known about this impact on terrestrial invertebrates, even though they are known to easily accumulate pollutants. We studied the effect of industrial heavy metal contamination on immune defense of a free-living wood ant (Formica aquilonia). To find out whether ants show an adapted immune function in a polluted environment, we compared encapsulation responses between local and translocated colonies. Local colonies showed higher heavy metal levels than the translocated ones but the encapsulation response was similar between the two groups, indicating that the immune system of local ants has not adapted to high contamination level. The encapsulation response was elevated in moderate whereas suppressed in high heavy metal levels suggesting higher risk for infections in heavily polluted areas. PMID:16635539

Sorvari, Jouni; Rantala, Liisa M; Rantala, Markus J; Hakkarainen, Harri; Eeva, Tapio

2007-01-01

216

Heavy metal content of black teas consumed in Iran.  

PubMed

Tea (Camellia sinensis) is the most widely consumed beverage in several parts of the world. Tea consumption is a major component of the traditional Iranian diet; however, limited data are available indicating heavy metals content of this beverage. This study aimed to assess concentrations of heavy metals, including copper, lead, cadmium, chromium and mercury as well as minerals like zinc and iron in black tea samples. Atomic absorption spectrometry was used to determine the elements of interest in 20 brands of black tea that are widely consumed among Iranians. The mean concentrations were 28.8 for Zn, 135.2 for Fe, 15.9 for Cu and 8.2 for Cr (mg kg?¹) and 134.5 for Cd, 209.5 for Pb and 40 for Hg (µg kg?¹). It is concluded that tea consumption can be a possible source of some heavy metal intake for the Iranian population. PMID:24779877

Falahi, Ebrahim; Hedaiati, Roshanak

2013-01-01

217

Characterization of a heavy metal translocating P-type ATPase gene from an environmental heavy metal resistance Enterobacter sp. isolate.  

PubMed

Heavy metals are common contaminants found in polluted areas. We have identified a heavy metal translocating P-type ATPase gene (hmtp) via fosmid library and in vitro transposon mutagenesis from an Enterobacter sp. isolate. This gene is believed to participate in the bacterium's heavy metal resistance traits. The complete gene was identified, cloned, and expressed in a suitable Escherichia coli host cell. E. coli W3110, RW3110 (zntA::Km), GG48 (?zitB::Cm zntA::Km), and GG51 (?zitB::Cm) were used to study the possible effects of this gene for heavy metal (cadmium and zinc in particular) resistance. Among the E. coli strains tested, RW3110 and GG48 showed more sensitivity to cadmium and zinc compared to the wild-type E. coli W3110 and strain GG51. Therefore, strains RW3110 and GG48 were chosen for the reference hosts for further evaluation of the gene's effect. The results showed that expression of this heavy metal translocating P-type ATPase gene could increase the ability for zinc and cadmium resistance in the tested microorganisms. PMID:23344939

Chien, Chih-Ching; Huang, Chia-Hsuan; Lin, Yi-Wei

2013-03-01

218

Animal Hair as Biological Indicator for Heavy Metal Pollution in Urban and Rural Areas  

Microsoft Academic Search

Animal hair is a good biomonitoring tool for heavy metals assessment and reflects the content of heavy metals in the forage and soil. Heavy metals Fe, Mn, Co and Ni as well as toxic metals Cd and Pb were determined in goat, sheep and camel hair, forage and soil collected from four different environmental urban and rural regions. These regions

M. Nageeb Rashed; M. E. Soltan

2005-01-01

219

Phytoremediation of heavy metal-contaminated land by trees—a review  

Microsoft Academic Search

This paper reviews the potential for using trees for the phytoremediation of heavy metal-contaminated land. It considers the following aspects: metal tolerance in trees, heavy metal uptake by trees grown on contaminated substrates, heavy metal compartmentalisation within trees, phytoremediation using trees and the phytoremediation potential of willow (Salix spp.).

I. D. Pulford; C. Watson

2003-01-01

220

Heavy metal vaporization and abatement during thermal treatment of modified wastes  

Microsoft Academic Search

This study examines the vaporization percentage and partitioning of heavy metals Cd, Pb and Zn during thermal treatment of wastes with added PVC, heavy metals or phosphate, and the efficiency of sorbents for removal of these metallic compounds in flue gas of an industrial solid waste incinerator. Firstly, vaporization experiments were carried out to determine the behavior of heavy metals

S. Rio; C. Verwilghen; J. Ramaroson; A. Nzihou; P. Sharrock

2007-01-01

221

Tunable Biopolymers for Heavy Metal Removal Jan Kostal, Ashok Mulchandani, and Wilfred Chen*  

E-print Network

Tunable Biopolymers for Heavy Metal Removal Jan Kostal, Ashok Mulchandani, and Wilfred Chen synthesized for the removal of heavy metals from dilute waste streams. Protein-protein interaction persistent nature, heavy metal ions are major contributors to pollution of the biosphere.1,2 These metals

Chen, Wilfred

222

Detection of Heavy Metal Ions in Water by High-Resolution Surface Plasmon Resonance  

E-print Network

Detection of Heavy Metal Ions in Water by High-Resolution Surface Plasmon Resonance Spectroscopy voltammetry (ASV) capability has been demonstrated for detecting heavy metal ions in water. Metal ions in water from part-per-million to sub-part-per-billion levels with good linearity. Heavy metal poisoning

Zhang, Yanchao

223

Heavy metal geochemistry of the Pontchartrain-Maurepas estuarine complex  

SciTech Connect

The Pontchartrain-Maurepas estuarine complex has become the focus of an intense debate concerning hydraulic shell dredging and its effects. Besides disrupting the benthic community, it has been alleged by the opponents of shell dredging that the mining process releases harmful concentrations of heavy metals into the water column. Bottom sediment heavy metal data combined with ion-site partitioning analyses provide a basis for estimating heavy metal release during dredging. The concentrations of Cu, Cr, Ni, Fe, Zn, V, Co, Pb, and Ba were determined for bottom sediment samples collected during 1987. The areal distribution of metals in the complex is controlled largely by sediment texture. As the clay content of the sediment increases, so does metal content. This observation seems to hold for most estuaries along the northern Gulf of Mexico. The concentrations of all metals except Pb were found to be positively correlated with Fe-content. Comparison of average metal contents with data from other estuaries along the Gulf Coast indicates that the complex has not been heavily impacted by anthropogenic input of metals. Because dredging disrupts redox conditions in the sediment, the potential release of metals into the water column is a real concern. However, partitioning analyses indicate that the majority of metal present in the bottom sediments is in relatively stable phases. The metal content of the exchangeable and organic phases, which are most easily affected by redox changes, was found to be minor. The rapid process of hydraulic shell mining, the positive Eh of the lake water, and the fine-grained suspended sediments result in a minor impact of dredging on water quality. Released metals are rapidly scavenged by adsorption and coprecipitation reactions.

Flowers, G.C. (Tulane Univ., New Orleans, LA (USA)); Isphording, W.C. (Univ. of South Alabama, Mobile (USA))

1990-09-01

224

PHYTOEXTRACTION OF HEAVY METALS WITH HYPERACCUMULATOR PLANTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

When soils contain metals at high enough levels to comprise risk thru food-chain or soil ingestion, some methods must be applied to alleviate the risk, or the land use must be constrained. One approach to remediate risks from some metals is phytoextraction using hyperaccumulator plants. These remark...

225

Biosorbents for toxic heavy metals - A review  

Microsoft Academic Search

The present investigation shows that the agricultural by-products like bengal gram husk, tur dal husk, and tamarind husk can be used as an effective adsorbent for the treatment of wastewaters containing metals like chromium (VI), iron (III), nickel (II) and mercury (II). The term biosorption commonly refers to the passive binding of metal ions or radioactive elements by dead biomass.

S. Vijaya Priya; M. Arulmozhi

2012-01-01

226

Heavy metal concentrations along the Louisiana coastal zone  

SciTech Connect

Cores were taken from seven locations in southern Louisiana and analyzed for concentrations of heavy metals. Sedimentation rates for the locations were determined using the /sup 137/Cs dating technique. Correlations of metals with depth were calculated using absolute, aluminum normalized, and iron normalized concentrations. Correlations indicated recent increases at several sites (Lake Palourde, Manchac Pass, and Wax Lake Outlet) for several metals (Pb, Cd, Cr, Ni, Zn) when profiles were normalized to aluminum. Metal profiles from rapidly-accreting areas (Atchafalaya and Four league Bay) did not show historical increases comparable to areas accreting less rapidly (e.g., Wax Lake Outlet, Manchac Pass, and Lake Palourde).

Pardue, J.H.; DeLaune, R.D.; Smith, C.J.; Patrick, W.H. Jr.

1988-01-01

227

Oil palm biomass as an adsorbent for heavy metals.  

PubMed

Many industries discharge untreated wastewater into the environment. Heavy metals from many industrial processes end up as hazardous pollutants of wastewaters.Heavy metal pollution has increased in recent decades and there is a growing concern for the public health risk they may pose. To remove heavy metal ions from polluted waste streams, adsorption processes are among the most common and effective treatment methods. The adsorbents that are used to remove heavy metal ions from aqueous media have both advantages and disadvantages. Cost and effectiveness are two of the most prominent criteria for choosing adsorbents. Because cost is so important, great effort has been extended to study and find effective lower cost adsorbents.One class of adsorbents that is gaining considerable attention is agricultural wastes. Among many alternatives, palm oil biomasses have shown promise as effective adsorbents for removing heavy metals from wastewater. The palm oil industry has rapidly expanded in recent years, and a large amount of palm oil biomass is available. This biomass is a low-cost agricultural waste that exhibits, either in its raw form or after being processed, the potential for eliminating heavy metal ions from wastewater. In this article, we provide background information on oil palm biomass and describe studies that indicate its potential as an alternative adsorbent for removing heavy metal ions from wastewater. From having reviewed the cogent literature on this topic we are encouraged that low-cost oil-palm-related adsorbents have already demonstrated outstanding removal capabilities for various pollutants.Because cost is so important to those who choose to clean waste streams by using adsorbents, the use of cheap sources of unconventional adsorbents is increasingly being investigated. An adsorbent is considered to be inexpensive when it is readily available, is environmentally friendly, is cost-effective and be effectively used in economical processes. The advantages that oil palm biomass has includes the following:available and exists in abundance, appears to be effective technically, and can be integrated into existing processes. Despite these advantages, oil palm biomasses have disadvantages such as low adsorption capacity, increased COD, BOD and TOC. These disadvantages can be overcome by modifying the biomass either chemically or thermally. Such modification creates a charged surface and increases the heavy metal ion binding capacity of the adsorbent. PMID:24984835

Vakili, Mohammadtaghi; Rafatullah, Mohd; Ibrahim, Mahamad Hakimi; Abdullah, Ahmad Zuhairi; Salamatinia, Babak; Gholami, Zahra

2014-01-01

228

Crystallographic phases in heavy rare earth metals under megabar pressures  

NASA Astrophysics Data System (ADS)

Experiments aimed at understanding the crystallographic phases of heavy rare earth metals were carried out in a diamond anvil cell at the Advanced Photon Source, Argonne National Laboratory. Heavy rare earth metals dysprosium (Dy), holmium (Ho), erbium (Er) and thulium (Tm) were compressed to multi-megabar pressures. The rare earth crystal sequence hcp?Sm-type?dhcp?distorted-fcc (dfcc) is observed in all four elements. Upon further compression, a structural transformation to a monoclinic C2/m phase has been observed. We summarize the results from these experiments and present Rietveld structural refinements on high pressure phases for the specific case of dysprosium.

Samudrala, G. K.; Vohra, Y. K.

2012-07-01

229

Black Hole Thermodynamics and Heavy Fermion Metals  

E-print Network

Heavy fermion alloys at critical doping typically exhibit non-Fermi-liquid behavior at low temperatures, including a logarithmic or power law rise in the ratio of specific heat to temperature as the temperature is lowered. Anomalous specific heat of this type is also observed in a simple class of gravitational dual models that exhibit anisotropic scaling with dynamical critical exponent z > 1.

E. J. Brynjolfsson; U. H. Danielsson; L. Thorlacius; T. Zingg

2010-08-10

230

Transformation of heavy metal speciation during sludge drying: mechanistic insights.  

PubMed

Speciation can fundamentally affect on the stability and toxicity of heavy metals in sludge from wastewater treatment plants. This research investigated the speciation of heavy metals in sludge from both municipal and industrial sources, and metal speciation change as a result of drying process to reduce sludge volume. The changes in sludge properties including sludge moisture content, temperature, density, and electrical conductivity were also monitored to provide insights into the mechanisms causing the change in heavy metal speciation. The results show that the drying process generally stabilized Cr, Cu, Cd, and Pb in sludge by transforming acid-soluble, reducible, and oxidizable species into structurally stable forms. Such transformation and stabilization occurred regardless of the sludge source and type, and were primarily caused by the changes in sludge properties associated with decomposition of organic matter and sulfide. The results enhanced our understanding of the geochemical behavior of heavy metals in municipal sludge, and are useful for designing a treatment system for environment-friendly disposal of sludge. PMID:24342049

Weng, Huan-Xin; Ma, Xue-Wen; Fu, Feng-Xia; Zhang, Jin-Jun; Liu, Zan; Tian, Li-Xun; Liu, Chongxuan

2014-01-30

231

Coal burning leaves toxic heavy metal legacy in the Arctic  

SciTech Connect

Toxic heavy metals emitted by industrial activities in the midlatitudes are transported through the atmosphere and deposited in the polar regions; bioconcentration and biomagnification in the food chain mean that even low levels of atmospheric deposition may threaten human health and Arctic ecosystems. Little is known about sources and long-term trends of most heavy metals before approximate to 1980, when modern measurements began, although heavy-metal pollution in the Arctic was widespread during recent decades. Lacking detailed, long-term measurements until now, ecologists, health researchers, and policy makers generally have assumed that contamination was highest during the 1960s and 1970s peak of industrial activity in North America and Europe. We present continuous 1772-2003 monthly and annually averaged deposition records for highly toxic thallium, cadmium, and lead from a Greenland ice core showing that atmospheric deposition was much higher than expected in the early 20th century, with tenfold increases from preindustrial levels by the early 1900s that were two to five times higher than during recent decades. Tracer measurements indicate that coal burning in North America and Europe was the likely source of these metals in the Arctic after 1860. Although these results show that heavy-metal pollution in the North Atlantic sector of the Arctic is substantially lower today than a century ago, contamination of other sectors may be increasing because of the rapid coal-driven growth of Asian economies.

McConnell, J.R.; Edwards, R. [Desert Research Institute, Reno, NV (United States)

2008-08-26

232

Coal burning leaves toxic heavy metal legacy in the Arctic.  

PubMed

Toxic heavy metals emitted by industrial activities in the midlatitudes are transported through the atmosphere and deposited in the polar regions; bioconcentration and biomagnification in the food chain mean that even low levels of atmospheric deposition may threaten human health and Arctic ecosystems. Little is known about sources and long-term trends of most heavy metals before approximately 1980, when modern measurements began, although heavy-metal pollution in the Arctic was widespread during recent decades. Lacking detailed, long-term measurements until now, ecologists, health researchers, and policy makers generally have assumed that contamination was highest during the 1960s and 1970s peak of industrial activity in North America and Europe. We present continuous 1772-2003 monthly and annually averaged deposition records for highly toxic thallium, cadmium, and lead from a Greenland ice core showing that atmospheric deposition was much higher than expected in the early 20th century, with tenfold increases from preindustrial levels by the early 1900s that were two to five times higher than during recent decades. Tracer measurements indicate that coal burning in North America and Europe was the likely source of these metals in the Arctic after 1860. Although these results show that heavy-metal pollution in the North Atlantic sector of the Arctic is substantially lower today than a century ago, contamination of other sectors may be increasing because of the rapid coal-driven growth of Asian economies. PMID:18711138

McConnell, Joseph R; Edwards, Ross

2008-08-26

233

Transformation of heavy metal speciation during sludge drying: mechanistic insights  

SciTech Connect

Speciation can fundamentally affect on the stability and toxicity of heavy metals in sludge from wastewater treatment plants. This research investigated the speciation of heavy metals in sludge from both municipal and industrial sources, and metal speciation change as a result of drying process to reduce sludge volume. The changes in sludge properties including sludge moisture content, temperature, density, and electrical conductivity were also monitored to provide insights into the mechanisms causing the change in heavy metal speciation. The results show that the drying process generally stabilized the Cr, Cu, Cd and Pb in sludge by transforming acid-soluble, reducible and oxidizable species into structurally stable forms. Such transformation and stabilization occurred regardless of the sludge source and type, and were primarily caused by the changes in sludge properties associated with decomposition of organic matter and sulfide. The results enhanced our understanding of the geochemical behavior of heavy metals in municipal sludge, and are useful for designing a treatment system for environment-friendly disposal of sludge.

Weng, Huanxin; Ma, Xue-Wen; Fu, Feng-Xia; Zhang, Jin-Jun; Liu, Zan; Tian, Li-Xun; Liu, Chongxuan

2014-01-30

234

Heavy metals in stream sediments: Effects of human activities  

NASA Astrophysics Data System (ADS)

The content of 11 heavy metals in the sediments of a stream system was determined by atomic absorption analysis. Geochemical phases were investigated using a sequential extraction scheme, and bulk contents were assessed with a single HNO3 extraction. Certain heavy metals were associated with different geochemical phases. Co, Mn, and Ba concentrated primarily in the carbonate and Mn phases, while all the remaining metals concentrated in the Fe and remnant phases. Features located along the stream system influenced the content of heavy metals. Results from the geochemical phases indicated Cu, Pb, Zn, Cd and Ag were emitted by one landfill, while Cd, Ba, and Ag were emitted by a second landfill. A wastewater treatment facility appeared to emit Ni and Cu. A stream draining a reservoir and joining the study stream resulted in dilution of the heavy metals in the sediments. A populated area along the study stream appeared to emit Mn. The single HNO3 extraction procedure is quicker to perform than the sequential extraction but does not indicate the phase associations.

Mantei, Erwin J.; Foster, Melvin V.

1991-09-01

235

Effects of sediment geochemical properties on heavy metal bioavailability.  

PubMed

As the largest container and resource of metals, sediment has a special role in the fate of metals. Factors influencing bioavailability of heavy metals in sediment have never been comprehensively considered and the sediment properties still fail to understand and even controversial. In this review, the mechanisms of sediment properties such as acid-volatile sulfides (AVS), organic matter, texture (clay, silt or sand) and geology, organism behaviors as well as those influencing the bioavailability of metals were analyzed. Under anoxic condition, AVS mainly reduce the solubility and toxicity of metals, while organic matters, Fe-Mn oxides, clay or silt can stabilize heavy metals in elevated oxidative-reductive potential (ORP). Other factors including the variation of pH, redox potential, aging as well as nutrition and the behavior of benthic organism in sediment also largely alter metals mobility and distribution. These factors are often inter-related, and various toxicity assessment methods used to evaluate the bioavailability of trace metals have been also discussed. Additionally, we expect that some novel synthetic materials like polysulfides, nano-materials, provide the substantial amendments for metals pollution in sediment. PMID:25173943

Zhang, Chang; Yu, Zhi-gang; Zeng, Guang-ming; Jiang, Min; Yang, Zhong-zhu; Cui, Fang; Zhu, Meng-ying; Shen, Liu-qing; Hu, Liang

2014-12-01

236

Control of heavy metals during incineration using activated carbon fibers.  

PubMed

Activated carbon fibers (ACFs) were applied to control heavy metals in incineration flue gas. Three heavy metal species (Cr, Cd and Pb), three ACFs, various adsorption temperatures (150, 250 and 300 degrees C) and weights of ACFs were experimentally determined. The results indicated that the effects of the type of ACF and the weight of the ACFs on the solid-state Cr removal were insignificant. The extent of solid-state Cd and Pb removal was related to the knitting structure of ACFs and the physical characteristic of the metals. The removal efficiencies of the solid-state and gaseous metals at various reaction temperature followed the order 250>150>300 degrees C and 300>250>150 degrees C, respectively. PMID:17011121

Liu, Zhen Shu

2007-04-01

237

Phytoremediation of heavy metal contaminated soil by Jatropha curcas.  

PubMed

This study employed Jatropha curcas (bioenergy crop plant) to assist in the removal of heavy metals from contaminated field soils. Analyses were conducted on the concentrations of the individual metals in the soil and in the plants, and their differences over the growth periods of the plants were determined. The calculation of plant biomass after 2 years yielded the total amount of each metal that was removed from the soil. In terms of the absorption of heavy metal contaminants by the roots and their transfer to aerial plant parts, Cd, Ni, and Zn exhibited the greatest ease of absorption, whereas Cu, Cr, and Pb interacted strongly with the root cells and remained in the roots of the plants. J. curcas showed the best absorption capability for Cd, Cr, Ni, and Zn. This study pioneered the concept of combining both bioremediation and afforestation by J. curcas, demonstrated at a field scale. PMID:25236867

Chang, Fang-Chih; Ko, Chun-Han; Tsai, Ming-Jer; Wang, Ya-Nang; Chung, Chin-Yi

2014-12-01

238

Heavy metal concentration in bay sediments of Japan  

SciTech Connect

Because industry discharge wastes into the sea, marine sediments can be contaminated with various kinds of hazardous and toxic substances. This study discusses how the degree of pollution of heavy metals affects the marine sediments from Osaka Bay and Tokyo Bay. In this study, the concentrations of various metals, such as manganese, iron, aluminum, titanium, vanadium, copper, phosphorus, etc., were measured from sediment samples obtained from different sites in the bays. However, the results had to be corrected because background concentrations for each metal differ with site location and grain size characteristics. The large difference between background and individual concentrations at various soil depths indicates that the surface layers of the seabed are significantly polluted with some species of heavy metal and other elements.

Fukue, Masaharu; Kato, Yoshihisa; Nakamura, Takaaki [Tokai Univ., Shimizu (Japan); Yamasaki, Shoichi [Aoki Marine Ltd., Fukushima, Osaka (Japan)

1995-12-31

239

Heavy metal and abiotic stress inducible metallothionein isoforms from Prosopis juliflora (SW) D.C. show differences in binding to heavy metals in vitro  

Microsoft Academic Search

Prosopis juliflora is a tree species that grows well in heavy metal laden industrial sites and accumulates heavy metals. To understand the possible\\u000a contribution of metallothioneins (MTs) in heavy metal accumulation in P. juliflora, we isolated and compared the metal binding ability of three different types of MTs (PjMT1-3). Glutathione S-transferase fusions of PjMTs (GSTMT1-3) were purified from Escherichia coli

B. Usha; Gayatri Venkataraman; Ajay Parida

2009-01-01

240

Heavy metal biosorption by bacterial cells  

Microsoft Academic Search

Microbial biomass provides available ligand groups on which metal ions bind by different mechanisms. Biosorption of these\\u000a elements from aqueous solutions represents a remediation technology suitable for the treatment of metal-contaminated effluents.\\u000a The purpose of the present investigation was the assessment of the capability of Brevibacterium sp. cells to remove bivalent ions, when present alone or in pairs, from aqueous

A. Vecchio; Carlo Finoli; Damiano Di Simine; Vincenza Andreoni

1998-01-01

241

Movement of heavy metals below sewage disposal ponds  

Microsoft Academic Search

Coarse-textured soils below sludge and effluent disposal ponds at two sewage treatment plants were studied. The concentrations of Zn, Cd, Cu, Cr, and Ni in the soils at various depths were determined to investigate the downward movement of these heavy metals below the two types of disposal ponds. Concentrations of acid-extractable metals (4N HNOâ) were greater under disposal ponds than

L. J. Lund; A. L. Page; C. O. Nelson

1976-01-01

242

Heavy metal removal by biosorption using Phanerochaete chrysosporium  

Microsoft Academic Search

Biosorption using microbial cells as adsorbents is being seen as a cost-effective method for the removal of heavy metals from\\u000a wastewaters. Biosorption studies with Phanerochaete chrysosporium were performed for copper (II), lead (II), and cadmium (II) to evaluate the effectiveness and to optimize the operational\\u000a parameters using response surface methodology. The operational parameters chosen were initial metal ion concentration, pH,

M. Gopal; K. Pakshirajan; T. Swaminathan

2002-01-01

243

Heavy Metals Remediation of Water Using Plants and Lignocellulosic Agrowastes  

Microsoft Academic Search

Metals in the environment arise from natural sources or directly or indirectly from human activities such as rapid industrialization,\\u000a urbanization, and anthropogenic sources, threatening the environment and human health (Nriagu 1979). Mining and metallurgical activities produce wastewaters that can be considered as the major source of heavy metal contamination\\u000a of natural waters (Schalcsha and Ahumada 1998; Reddad et al. 2002a).

K. K. Krishnani; S. Ayyappan

244

Heavy metal accumulation by bacteria and other microorganisms  

Microsoft Academic Search

Summary Bacteria, and other microorganisms, exhibit a number of metabolism-dependent and-independent processes or the uptake and accumulation of heavy metals and radionuclides. The removal of such harmful substances from effluents and waste waters by microbe-based technologies may provide an alternative or additional means of metal\\/radionuclide recovery for economic reasons and\\/or environmental protection. Both living and dead cells as well as

G. M. Gadd

1990-01-01

245

Heavy metal detoxification in higher plants - a review  

Microsoft Academic Search

A set of heavy-metal-complexing peptides was isolated from plants and plant suspension cultures. The structure of these peptides was established as (?-glutamic acid-cysteine)n-glycine (n=2–11) [(?-Glu-Cys)n-Gly]. These peptides appear upon induction of plants with metals of the transition and main groups (Ib-Va, Z=29?83) of the periodic table of elements. These peptides, called phytochelatins (PC), are induced in all autotrophic plants so

Meinhart H. Zenk

1996-01-01

246

Sorption of Heavy Metal Ions on New Metal-Ligand Complexes Chemically Derived from Lycopodium clavatum  

Microsoft Academic Search

Sorption of heavy metal ions from aqueous solution has been investigated as a function of pH using a novel exchanger system whereby Lycopodium clavatum is functionalized with carboxylate and glyoxime metal-ligand complexes. The new ligand exchangers were prepared using a reaction of diaminosporopollenin with various metal-ligand complexes of glyoxime and monocarboxylic acid. The sorptive behavior of these metal-ligand exchangers and

Erol Pehlivan; Mustafa Ersoz; Salih Yildiz; Harry J. Duncan

1994-01-01

247

Mechanisms of heavy metal removal using microorganisms as biosorbent.  

PubMed

Release and distribution of heavy metals through industrial wastewaters has adverse affects on the environment via contamination of surface- and ground-water resources. Biosorption of heavy metals from aqueous solutions has been proved to be very promising, offering significant advantages such as low cost, availability, profitability, ease of operation, and high efficiency, especially when dealing with low concentrations. Residual biomasses of industrial microorganisms including bacteria, algae, fungi, and yeast have been found to be capable of efficiently accumulating heavy metals as biosorbent. This paper presents and investigates major mechanisms of biosorption and most of the functional groups involved. The biosorption process includes the following mechanisms: transport across cell membrane, complexation, ion exchange, precipitation, and physical adsorption. In order to understand how metals bind to the biomass, it is essential to identify the functional groups responsible for metal binding. Most of these groups have been characterized on the cell walls. The biosorbent contains a variety of functional sites including carboxyl, imidazole, sulfydryl, amino, phosphate, sulfate, thioether, phenol, carbonyl, amide, and hydroxyl moieties that are responsible for metal adsorption. These could be helpful to improve biosorbents through modification of surface reactive sites via surface grafting and/or exchange of functional groups. PMID:24804650

Javanbakht, Vahid; Alavi, Seyed Amir; Zilouei, Hamid

2014-01-01

248

Use of cestodes as indicator of heavy-metal pollution.  

PubMed

Thirty snakehead fish, Channa micropeltes (Cuvier, 1831) were collected at Lake Kenyir, Malaysia. Muscle, liver, intestine and kidney tissues were removed from each fish and the intestine was opened to reveal cestodes. In order to assess the concentration of heavy metal in the environment, samples of water in the surface layer and sediment were also collected. Tissues were digested and the concentrations of manganese (Mn), zinc (Zn), copper (Cu), cadmium (Cd) and lead (Pb) were analysed by using inductively-coupled plasma mass-spectrometry (ICP-MS) equipment. The results demonstrated that the cestode Senga parva (Fernando and Furtado, 1964) from fish hosts accumulated some heavy metals to a greater extent than the water and some fish tissues, but less than the sediment. In three (Pb, Zn and Mn) of the five elements measured, cestodes accumulated the highest metal concentrations, and in remaining two (Cu and Cd), the second highest metal accumulation was recorded in the cestodes when compared to host tissues. Therefore, the present study indicated that Senga parva accumulated metals and might have potential as a bioindicator of heavy-metal pollution. PMID:23146722

Yen Nhi, Tran Thi; Mohd Shazili, Noor Azhar; Shaharom-Harrison, Faizah

2013-01-01

249

Customizable biopolymers for heavy metal remediation Jan Kostal, Giridhar Prabhukumar, U. Loi Lao, Alin Chen, Mark Matsumoto, Ashok Mulchandani and  

E-print Network

Customizable biopolymers for heavy metal remediation Jan Kostal, Giridhar Prabhukumar, U. Loi Lao for heavy metals because conventional technologies are often inadequate to reduce concentrations properties for heavy metal removal is summarized. Several different strategies for the selective removal

Chen, Wilfred

250

Anaerobes into heavy metal: Dissimilatory metal reduction in anoxic environments  

USGS Publications Warehouse

Within the last decade, a novel form of microbial metabolism of major environmental significance has been elucidated. In this process, known as dissimilatory metal reduction, specialized microorganisms, living in anoxic aquatic sediments and ground water, oxidize organic compounds to carbon dioxide with metals serving as the oxidant. Recent studies have demonstrated that this metabolism explains a number of important geochemical phenomena in ancient and modern sedimentary environments, affecting not only the cycling of metals but also the fate of organic matter. Furthermore, this metabolism may have practical application in remediation of environments contaminated with toxic metals and/or organics.

Lovley, D.R.

1993-01-01

251

Bioaccumulation of heavy metals by green algae.  

PubMed

The biosorption of metal ions (Cr(+3), Cr(2)O(7)(-2), Cu(+2), and Ni(+2)) on two algal blooms (designated HD-103 and HD-104) collected locally was investigated as a function of the initial metal ion concentration. The main constituent of HD-103 is Cladophora sp., while Spirulina sp. is present significantly in the bloom HD-104. Algal biomass HD-103 exhibited the highest Cu(+2) uptake capacity (819 mg/g). This bloom adsorbed Ni(+2) (504 mg/g), Cr(+3) (347 mg/g), and Cr(2)O(7)(-2), (168 mg/g). Maximum of Ni(+2) (1108 mg/g) is taken by HD-104. This species takes up 306, 202, and 576 mg/g Cr(+3), Cr(2)O(7)(-2), and Cu(+2), respectively. Equilibrium data fit very well to both the Langmuir and the Freundlich isotherm models. The sorption process followed the Freundlich model better. Pseudo-first-order kinetic model could describe the kinetic data. Infrared (IR) spectroscopic data were employed to identify the site(s) of bonding. It was found that phosphate and peptide moieties participate in the metal uptake by bloom HD-103. In the case of bloom HD-104, carboxylate and phosphate are responsible for the metal uptake. The role of protein in metal uptake by HD-103 was investigated using polyacrylamide gel electrophoresis. PMID:18167026

Doshi, Hiren; Seth, Chetan; Ray, Arabinda; Kothari, I L

2008-03-01

252

Using biopolymers to remove heavy metals from soil and water  

Microsoft Academic Search

Chemical remediation of soil may involve the use of harsh chemicals that generate waste streams, which may adversely affect the soil's integrity and ability to support vegetation. This article reviews the potential use of benign reagents, such as biopolymers, to extract heavy metals. The biopolymers discussed are chitin and chitosan, modified starch, cellulose, and polymer-containing algae. (Copyright (c) Remediation 1994.)

S. Krishnamurthy; R. M. Frederick

1993-01-01

253

HEAVY METAL CONTAMINATION IN THE TAIMYR PENINSULA, SIBERIAN ARCTIC  

EPA Science Inventory

The Taimyr Peninsula is directly north of the world's largest heavy metal smelting complex (Norilsk, Russia). Despite this proximity, there has been little research to examine the extent of contamination of the Taimyr Peninsula, primarily because of the remoteness of this area. W...

254

Standardisation of heavy metal biosorption tests: equilibrium and modelling study  

Microsoft Academic Search

The use of some microorganisms to remove heavy metals from contaminated industrial wastewaters may represent an innovative purification process. Several aspects must be taken into consideration for complete process development. Standardisation of the experimental procedures, equilibrium and kinetic modelling and related statistical data analysis represent in general the first steps of these studies. Screening experimental tests have to be performed

F. Vegliò; A. Esposito; A. P. Reverberi

2003-01-01

255

Organochlorines, heavy metals, and the biology of North American accipiters  

USGS Publications Warehouse

Analyses of eggs of three species of North American accipitrine hawks for organochlorines and heavy metals indicate that contamination with DDE may be the primary cause of recent population declines of two of the species, Cooper's hawk and sharp-shinned hawk.

Snyder, N.F.R.; Snyder, H.A.; Lincer, J.L.; Reynolds, R.T.

1973-01-01

256

Adolescents and Heavy Metal Music: From the Mouths of Metalheads.  

ERIC Educational Resources Information Center

Attitudes and characteristics of adolescents who like heavy metal music (HMM) were explored in a study of 52 adolescents (largely White males) who liked HMM and 123 who did not in suburban Atlanta (Georgia). HMM is discussed as a reflection of, rather than a cause of, adolescent alienation. (SLD)

Arnett, Jeffrey

1991-01-01

257

Using biopolymers to remove heavy metals from soil and water  

SciTech Connect

Chemical remediation of soil may involve the use of harsh chemicals that generate waste streams, which may adversely affect the soil's integrity and ability to support vegetation. This article reviews the potential use of benign reagents, such as biopolymers, to extract heavy metals. The biopolymers discussed are chitin and chitosan, modified starch, cellulose, and polymer-containing algae. (Copyright (c) Remediation 1994.)

Krishnamurthy, S.; Frederick, R.M.

1993-11-19

258

HEAVY METAL CONTENT OF AYURVEDIC HERBAL MEDICINE PRODUCTS  

EPA Science Inventory

Case reports of individuals taking Ayurvedic herbal medicine products (HMPs) suggest that they may contain lead, mercury, and/or arsenic. We analyzed the heavy metal content of Ayurvedic HMPs manufactured in India and Pakistan, available in South Asian grocery stores in the Bost...

259

MICROBIAL SEQUESTRATION OF LEAD AND OTHER HEAVY METALS  

EPA Science Inventory

Human activity resulting in heavy metal contamination is a worldwide concern. Lead is a potent neurotoxin that can cause heart problems, kidney damage, and mental retardation. Mercury causes toxicity based on its form and route of exposure. Effects range from allergic reactions t...

260

TREATMENT OF HEAVY METALS USING AN ORGANIC SULFATE REDUCING PRB  

EPA Science Inventory

A mpilot-scale permeable reactive wall consisting of a leaf-rich compost-pea gravel mixture was installed at a site in the Vancouver area, Canada to evaluate its potential use for treatment of a large dissolved heavy metal plume. The compost based permeable reactive wall promote...

261

Heavy Metal Accumulation in Wild Plants: Implications for Phytoremediation  

Microsoft Academic Search

This work addresses the issue of Zn, Cu, Pb, Cd, Ni and Cr accumulation in wildgrown plants in the context of their possible use for the sanitation of sludge and waste substrates. The highest contents of heavy metals were noted in Lactuca serriola, Chenopodium album, Artemisia vulgaris and Atriplex nitens. Assuming maxi- mum crop production which is to be obtained

G. Por?bska; A. Ostrowska

262

Heavy metals in composted municipal solid wastes for  

E-print Network

Heavy metals in composted municipal solid wastes for amendment of agricultural soils/ Métaux lourds dans le compost de déchets municipaux pour application agricole Valérie Duchesneau, #4634809 EVS4904 métaux lourds des compostes de déchets municipaux? http://www.ecometiers.com/fiche/images/43.jpg La

Blouin-Demers, Gabriel

263

Heavy Metal Pollution in Agricultural Soils of Changzhou, China  

Microsoft Academic Search

In order to investigate the environmental quality of agriculture in Changzhou, agricultural soils in 451 sampling points of six areas in Changzhou were sampled and tested for heavy metal concentrations. Single and compositive pollution indexes were used for the evaluation of the soils. The main results are listed below: (1) the soils were slightly polluted generally, and the compositive pollution

Jiakuan Xu; Tanyun Li; Meidi Ji; Jianguo Liu; Mingxin Wang

2011-01-01

264

Fraxinus excelsior as a Biomonitor of Heavy Metal Pollution  

Microsoft Academic Search

Fraxinus excelsior L. (Common Ash) is a deciduous tree that grows in wild and urban Turkey. Fraxinus excel- sior has been tested as a possible biomonitor of heavy metals in the city of Kayseri, Turkey. Forty-eight sites (urban road side, road side, urban park, industrial, suburban and rural sites) in and around the city of Kayseri were investi- gated. In

A. Aksoy; D. Demirezen

265

Lichens as Bioindicators of Atmospheric Heavy Metal Pollution in Singapore  

Microsoft Academic Search

Lichens have been used as bioindicators in various atmospheric pollution assessments in several countries. This study presents the first data on levels of heavy metals (As, Cd, Cu, Ni, Pb, and Zn) in lichens at different locations in Singapore, Southeast Asia. Singapore is a fully industrialised island nation, with a prevailing tropical climate and a population of 4 million people

O.-H. Ng; B. C. Tan; J. P. Obbard

2006-01-01

266

Characteristics on Soil Heavy Metals Pollution around Mine Waste Piles  

Microsoft Academic Search

Based on leaching experiment, the leaching of heavy metal in mine waste was brought out. The research showed that Zn, Cr, Pb and Cu concentrations are most in the leachate of weathered coal waste, and the concentration became stable rapidly; only Zn concentrations are found in fresh mine waste leachate in the beginning time. The soil around mine waste also

Mingliang Zhang; Haixia Wang

2009-01-01

267

HEAVY METALS CONTAMINATION IN TWO BIOLUMINESCENT BAYS OF PUERTO RICO  

E-print Network

HEAVY METALS CONTAMINATION IN TWO BIOLUMINESCENT BAYS OF PUERTO RICO Yadira Soto Viruet. The presence of arsenic, copper, iron, lead and mercury can affect Pyrodinium bahamense, which lives bioluminescent bays was high with respect to arsenic, and lead and mercury in most of the cases were below

Gilbes, Fernando

268

CONCENTRATION OF NINE HEAVY METALS IN SUEZ CANAL WATERS, EGYPT  

Microsoft Academic Search

The concentration of nine heavy metals (Cu, Zn, Cd, Pb, Ni, Cr, Co, Fe and Mn) in waters of the Suez Canal and in the nearby waters was measured seasonally during 1997 - 1998 in their dissolved (D) and particulate (P) forms. The results revealed that the northern part of the canal (at Port Said) recorded higher concentrations for most

EL SAMRA; ABD EL-AZIM

2005-01-01

269

Chemical methods and phytoremediation of soil contaminated with heavy metals  

Microsoft Academic Search

The effects of chemical amendments (calcium carbonate (CC), steel sludge (SS) and furnace slag (FS)) on the growth and uptake of cadmium (Cd) by wetland rice, Chinese cabbage and wheat grown in a red soil contaminated with Cd were investigated using a pot experiment. The phytoremediation of heavy metal contaminated soil with vetiver grass was also studied in a field

H. M Chen; C. R Zheng; C Tu; Z. G Shen

2000-01-01

270

Contribution of the arbuscular mycorrhizal symbiosis to heavy metal phytoremediation  

Microsoft Academic Search

High concentrations of heavy metals (HM) in the soil have detrimental effects on ecosystems and are a risk to human health as they can enter the food chain via agricultural products or contaminated drinking water. Phytoremediation, a sustainable and inexpensive technology based on the removal of pollutants from the environment by plants, is becoming an increasingly important objective in plant

Vera Göhre; Uta Paszkowski

2006-01-01

271

Optimization of heavy metals total emission, case study: Bor (Serbia)  

NASA Astrophysics Data System (ADS)

The town of Bor (Serbia) is one of the most polluted towns in southeastern Europe. The copper smelter which is situated in the centre of the town is the main pollutant, mostly because of its old technology, which leads to environmental pollution caused by higher concentrations of SO 2 and PM 10. These facts show that the word is about a very polluted region in Europe which, apart from harming human health in the region itself, poses a particular danger for wider area of southeastern Europe. Optimization of heavy metal's total emission was undertaken because years of long contamination of the soil with heavy metals of anthropogenic origin created a danger that those heavy metals may enter the food chains of animals and people, which can lead to disastrous consequences. This work represents the usage of Geographic Information System (GIS) for establishing a multifactor assessment model to quantitatively divide polluted zones and for selecting control sites in a linear programming model, combined with PROMETHEE/GAIA method, Screen View modeling system, and linear programming model. The results show that emissions at some control sites need to be cut for about 40%. In order to control the background of heavy metal pollution in Bor, the ecological environment must be improved.

Ili?, Ivana; Bogdanovi?, Dejan; Živkovi?, Dragana; Miloševi?, Novica; Todorovi?, Boban

2011-07-01

272

Heavy metal residues in tissues of marine turtles  

Microsoft Academic Search

Heavy metal concentrations in the tissues of marine turtles are presented. The most frequently monitored elements are mercury, cadmium and lead; and the tissues mainly analysed in nearly all the stranded individuals are muscle, liver and kidney. The highest mercury and cadmium levels were found in liver and kidney respectively; the majority of the lead burden existed in bones and

M. M Storelli; G. O Marcotrigiano

2003-01-01

273

Water Purification Using Functional Nanomaterials: Sequestering Toxic Heavy Metals  

Microsoft Academic Search

Water, and water quality, are issues of critical importance to the future of humankind. Our water supply has been contaminated by a wide variety of industrial, military and natural sources. There is a serious need for technologies to remove toxic heavy metals and radionuclides from the worlds water supplies. Surfactant templated synthesis of mesoporous ceramics provides a versatile foundation upon

Fryxell; Glen E

2008-01-01

274

Dendrochronology and heavy metal depsosition in tree rings of baldcypress  

Microsoft Academic Search

A chronology (1895-present) based on tree-ring increments was constructed for baldcypress (Taxodium distichum L.) trees in Bayou Trepagnier, in southern Louisiana. The best indicator of growth was precipitation in February of the preceding year and October of the 2 previous years. Crossdated cores were used to reconstruct large historical natural environmental perturbations (hurricanes). Heavy metals and organic pollutants from oil

Shane D. Latimer; E. G. Ellgaard; S. D. Kumar; Leonard B. Thien

1996-01-01

275

Situ formation of apatite for sequestering radionuclides and heavy metals  

Microsoft Academic Search

Methods for in situ formation in soil of a permeable reactive barrier or zone comprising a phosphate precipitate, such as apatite or hydroxyapatite, which is capable of selectively trapping and removing radionuclides and heavy metal contaminants from the soil, while allowing water or other compounds to pass through. A preparation of a phosphate reagent and a chelated calcium reagent is

Robert C

2003-01-01

276

Heavy Metal Transfer from Alkaline Soil to Forage Crops  

Microsoft Academic Search

In the Paso del Norte region along the Texas, U.S.-Mexico border, both rural and urban border communities are exposed to heavy metals from industry, copper smelting, combustion of petroleum products, and the reclamation of wastewaters for agricultural use (Fig. 1). The objectives of this study were to: i) investigate the chemistry of cadmium (Cd), chromium (Cr), nickel (Ni) and lead

Naomi Waissman Assadian; George Di Giovanni; Juan Pedro Margez Flores; Esaul Jaramillo Lopez

277

Screening Capsicum chinense fruits for heavy metals bioaccumulation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Elevated concentrations of heavy metals in edible plants could expose consumers to excessive levels of potentially hazardous chemicals. Sixty-three accessions (genotypes) of Capsicum chinense Jacq, collected from 8 countries of origin, were grown in a silty-loam soil under field conditions. At matur...

278

HEAVY METAL ADSORPTION BY MONTMORILLONITES MODIFIED WITH NATURAL ORGANIC CATIONS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Replacement of natural inorganic cations of clay minerals with organic cations has been proposed as a strategy to improve the adsorptive capacity of clay minerals for heavy metals. The organic cations most commonly used for this purpose have been quaternary ammonium ions containing alkyl or aryl cha...

279

Chelant extraction of heavy metals from contaminated soils  

Microsoft Academic Search

The current state of the art regarding the use of chelating agents to extract heavy metal contaminants has been addressed. Results are presented for treatability studies conducted as worst-case and representative soils from Aberdeen Proving Ground's J-Field for extraction of copper (Cu), lead (Pb), and zinc (Zn). The particle size distribution characteristics of the soils determined from hydrometer tests are

Robert W Peters

1999-01-01

280

The puzzling beat of heavy-metal stars  

NASA Astrophysics Data System (ADS)

A new group of low-mass chemically peculiar stars with helium-rich surfaces also seem to have layers of cloud rich in zirconium, strontium, yttrium and even lead. Simon Jeffery and colleagues are undertaking new observations in 2015 to understand the origin and unexplained pulsations of these heavy-metal stars.

Jeffery, Simon; Naslim, N.; Behara, Natalie; Hibbert, Alan

2015-04-01

281

Heavy metal contamination of soil and water in the vicinity of an abandoned e-waste recycling site: implications for dissemination of heavy metals.  

PubMed

Illegal e-waste recycling activity has caused heavy metal pollution in many developing countries, including China. In recent years, the Chinese government has strengthened enforcement to impede such activity; however, the heavy metals remaining in the abandoned e-waste recycling site can still pose ecological risk. The present study aimed to investigate the concentrations of heavy metals in soil and water in the vicinity of an abandoned e-waste recycling site in Longtang, South China. Results showed that the surface soil of the former burning and acid-leaching sites was still heavily contaminated with Cd (>0.39 mg kg(-1)) and Cu (>1981 mg kg(-1)), which exceeded their respective guideline levels. The concentration of heavy metals generally decreased with depth in both burning site and paddy field, which is related to the elevated pH and reduced TOM along the depth gradient. The pond water was seriously acidified and contaminated with heavy metals, while the well water was slightly contaminated since heavy metals were mostly retained in the surface soil. The use of pond water for irrigation resulted in considerable heavy metal contamination in the paddy soil. Compared with previous studies, the reduced heavy metal concentrations in the surface soil imply that heavy metals were transported to the other areas, such as pond. Therefore, immediate remediation of the contaminated soil and water is necessary to prevent dissemination of heavy metals and potential ecological disaster. PMID:25460954

Wu, Qihang; Leung, Jonathan Y S; Geng, Xinhua; Chen, Shejun; Huang, Xuexia; Li, Haiyan; Huang, Zhuying; Zhu, Libin; Chen, Jiahao; Lu, Yayin

2015-02-15

282

CONSTRUCTED WETLANDS FOR TREATMENT OF HEAVY METALS IN URBAN STORMWATER RUNOFF: CHEMICAL SPECIATION OF WETLAND SEDIMENTS  

EPA Science Inventory

Heavy metals in urban stormwater runoff are primarily removed by sedimentation in stormwater best management practices (BMPs) such as constructed wetlands. Heavy metals accumulated in wetland sediments may be potentially toxic to benthic invertebrates and aquatic microorganisms, ...

283

A sensitive rapid on-site immunoassay for heavy metal contamination  

SciTech Connect

This project concerns the development of immunoassays for heavy metals that will permit the rapid on-site analysis of specific heavy metals, including lead and chromium in water and soil samples. 2 refs.

Blake, R.; Blake, D.; Flowers, G.

1996-05-02

284

Characterisation of heavy metal tolerance and biosorption capacity of bacterium strain CPB4 (Bacillus spp.).  

PubMed

A heavy metal resistant bacterium Bacillus spp. strain CPB4 was isolated from heavy metal contaminated soil in Korea and further characterised. The CPB4 strain showed a high capacity for uptake of heavy metal Pb (Pb > Cd > Cu > Ni > Co > Mn > Cr > Zn) both in single and in mixed heavy metal solution. Optimal conditions for heavy metal uptakes of CPB4 strain were 20-40 degrees C culture temperature, 5-7 pH and 24 h pre-culture times. TEM showed that large amounts of the electron-dense granules (heavy metal complexes) were found mainly on the cell wall and cell membrane. Furthermore, more than 90% of adsorbed heavy metals were distributed both in cell wall and in cell membrane fractions. The amount of heavy metal uptake was remarkably decreased by reducing the crude protein contents when cells were treated by alkali solutions. Therefore, this study showed one of the possible examples for useful bioremediation. PMID:17305129

Kim, S U; Cheong, Y H; Seo, D C; Hur, J S; Heo, J S; Cho, J S

2007-01-01

285

The potential for heavy metal decontamination  

SciTech Connect

Preliminary trials to assess the ability of plant species to extract metals are presented. A range of zinc and nickel hyperaccumulator plants from the Brassicaceae family, collected from diverse populations in Europe, were grown on plots along with nonaccumulating crop plants from the same family. Extraction efficiencies and the number of croppings required to reduce the total zinc in the soil to a concentration of 300 mg/kg are tabulated. Zinc accumulation remained high over a wide range of soil metal concentration. However, the concentration of nickel in the hyperaccumulators increased in accordance with increasing total nickel concentrations in the soil. Calculations suggest that there is an excellent potential for using hyperaccumulator species to remove metals from the rhizosphere where remediation can be considered over a period of years and multiple cropping is a viable option.

Baker, A.J.M. [Univ. of Sheffield (United Kingdom); McGrath, S.P.; Sidoli, C.M.D. [AFRC Institute of Arable Crops Research, Harpenden (United Kingdom); Reeves, R.D. [Massey Univ., Palmerston North (New Zealand)

1996-12-31

286

Noninvasive Evaluation of Heavy Metal Uptake and Storage in Micoralgae Using a Fluorescence Resonance Energy Transfer-Based Heavy Metal Biosensor1[C][W][OPEN  

PubMed Central

We have developed a fluorescence resonance energy transfer (FRET)-based heavy metal biosensor for the quantification of bioavailable free heavy metals in the cytoplasm of the microalga Chlamydomonas reinhardtii. The biosensor is composed of an end-to-end fusion of cyan fluorescent protein (CFP), chicken metallothionein II (MT-II), and yellow fluorescent protein (YFP). In vitro measurements of YFP/CFP fluorescence emission ratios indicated that the addition of metals to the purified biosensor enhanced FRET between CFP and YFP, consistent with heavy metal-induced folding of MT-II. A maximum YFP/CFP FRET ratio of 2.8 was observed in the presence of saturating concentrations of heavy metals. The sensitivity of the biosensor was greatest for Hg2+ followed by Cd2+ ? Pb2+ > Zn2+ > Cu2+. The heavy metal biosensor was unresponsive to metals that do not bind to MT-II (Na+ and Mg2+). When expressed in C. reinhardtii, we observed a differential metal-dependent response to saturating external concentrations (1.6 mm) of heavy metals (Pb2+ > Cd2+) that was unlike that observed for the isolated biosensor (in vitro). Significantly, analysis of metal uptake kinetics indicated that equilibration of the cytoplasm with externally applied heavy metals occurred within seconds. Our results also indicated that algae have substantial buffering capacity for free heavy metals in their cytosol, even at high external metal concentrations. PMID:24368336

Rajamani, Sathish; Torres, Moacir; Falcao, Vanessa; Ewalt Gray, Jaime; Coury, Daniel A.; Colepicolo, Pio; Sayre, Richard

2014-01-01

287

Simultaneous heavy metal removal mechanism by dead macrophytes.  

PubMed

The use of dead, dried aquatic plants, for water removal of metals derived from industrial activities as a simple biosorbent material has been increasing in the last years. The mechanism of simultaneous metal removal (Cd2+, Ni2+, Cu2+, Zn2+ and Pb2+) by 3 macrophytes biomass (Spirodela intermedia, Lemna minor and Pistia stratiotes) was investigated. L. minor biomass presented the highest mean removal percentage and P. stratiotes the lowest for all metals tested. Pb2+ and Cd2+ were more efficiently removed by the three of them. The simultaneous metal sorption data were analysed according to Langmuir and Freundlich isotherms. Data fitted the Langmuir model only for Ni and Cd, but Freundlich isotherm for all metals tested, as it was expected. The K(F) values showed that Pb was the metal more efficiently removed from water solution. The adsorption process for the three species studied followed first order kinetics. The mechanism involved in biosorption resulted ion exchange between monovalent metals as counter ions present in the macrophytes biomass and heavy metal ions and protons taken up from water. No significant differences were observed in the metal exchange amounts while using multi-metal or individual metal solutions. PMID:15990152

Miretzky, Patricia; Saralegui, Andrea; Fernández Cirelli, Alicia

2006-01-01

288

Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops.  

PubMed

Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary toxicity. PMID:17173356

Islam, Ejaz ul; Yang, Xiao-e; He, Zhen-li; Mahmood, Qaisar

2007-01-01

289

Abolition of Heavy Metal Toxicity on Kirchneriella lunaris (Chlorophyta) by Calcium  

Microsoft Academic Search

The green alga Kirchneriella lunaris was incubated with various heavy metals (Cd2+, Co2+, Mn2+, Ni2+) in presence\\/absence of calcium (Ca2+). The uptake of heavy metal was affected by Ca2+. Growth rate was inhibited by all heavy metals applied. In all Ca2+-containing cultures Kirchneriella exhibited higher rates of growth than those containing heavy metal alone. Photosynthesis\\/respiration ratio of K. lunaris cells

A. A. Issa; R. Abdel-Basset; M. S. Adam

1995-01-01

290

Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops*  

PubMed Central

Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary toxicity. PMID:17173356

Islam, Ejaz ul; Yang, Xiao-e; He, Zhen-li; Mahmood, Qaisar

2007-01-01

291

Effects of heavy metals on microorganisms application to process design  

E-print Network

by Irvine and Schaezler (1) to show that plants receiving organic wastes with heavy metals present could possibly be controlled to provide optimum treatment at all times, It is shown that the four points listed below must be determined when considering... the formulation of unit growth rate for such wastes: (1) prediction of the functional rate form for biological growth; (2) rate as a function of metal, biomass, and substrate concentrations and pH; (3) effect of total metal concentration on growth rates; (4...

Heck, Robert Paul

1972-01-01

292

Succinylated machined corncobs: Titration and heavy metal ion binding characteristics  

SciTech Connect

The use of inexpensive natural materials for waste water treatment is economically attractive. In this study chemical modifications of an agricultural by-product, Lite-R-Cobs, were explored to increase its utility for reduction of metal ions in waste water effluent. Corn cob particles have been succinylated to increase their capacity for binding heavy metal ions. The carboxyl groups introduced into this cellulosic material were quantitated by base titration. Equilibrium metal ion binding characteristics of the material was studied for Cu{sup 2+}, Cd{sup 2+}, and Ni{sup 2+} ions.

McCall, R.C.; Getman, T.D.; Hunsley, J.R. [Southern Illinois Univ., Edwardsville, IL (United States)

1996-10-01

293

Heavy Metal Tolerance in Stenotrophomonas maltophilia  

PubMed Central

Stenotrophomonas maltophilia is an aerobic, non-fermentative Gram-negative bacterium widespread in the environment. S. maltophilia Sm777 exhibits innate resistance to multiple antimicrobial agents. Furthermore, this bacterium tolerates high levels (0.1 to 50 mM) of various toxic metals, such as Cd, Pb, Co, Zn, Hg, Ag, selenite, tellurite and uranyl. S. maltophilia Sm777 was able to grow in the presence of 50 mM selenite and 25 mM tellurite and to reduce them to elemental selenium (Se0) and tellurium (Te0) respectively. Transmission electron microscopy and energy dispersive X-ray analysis showed cytoplasmic nanometer-sized electron-dense Se0 granules and Te0 crystals. Moreover, this bacterium can withstand up to 2 mM CdCl2 and accumulate this metal up to 4% of its biomass. The analysis of soluble thiols in response to ten different metals showed eightfold increase of the intracellular pool of cysteine only in response to cadmium. Measurements by Cd K-edge EXAFS spectroscopy indicated the formation of Cd-S clusters in strain Sm777. Cysteine is likely to be involved in Cd tolerance and in CdS-clusters formation. Our data suggest that besides high tolerance to antibiotics by efflux mechanisms, S. maltophilia Sm777 has developed at least two different mechanisms to overcome metal toxicity, reduction of oxyanions to non-toxic elemental ions and detoxification of Cd into CdS. PMID:18253487

Pages, Delphine; Rose, Jerome; Conrod, Sandrine; Cuine, Stephane; Carrier, Patrick; Heulin, Thierry; Achouak, Wafa

2008-01-01

294

Phytoremediation of heavy metals from soils.  

PubMed

Phytoremediation offers owners and managers of metal-contaminated sites an innovative and cost-effective option to address recalcitrant environmental contaminants. The use of plants or plant products to restore or stabilize contaminated sites, collectively known as phytoremediation, takes advantage of the natural abilities of plants to take up, accumulate, store, or degrade organic and inorganic substances. Although not a new concept, phytoremediation is currently being re-examined as an environmentally friendly, cost-effective means of reducing metal contaminated soil and other substrates throughout North America and Europe. Processes include using plants that tolerate and accumulate metals at high levels (phytoextraction) and using plants that can grow under conditions that are toxic to other plants while preventing, for example, soil erosion (phytostabilization). Governments worldwide are establishing research and demonstration programs to use this potential. Environment Canada has developed a database (PHYTOREM) of 775 plants with capabilities to accumulate or hyperaccumulate one or several of 19 key metallic elements. This chapter addresses key research, potential benefits and limitations, and the potential future needs for phytoremediation. Issues related to intellectual property law, commercialization and public acceptance are touched on. PMID:12674400

McIntyre, Terry

2003-01-01

295

Simultaneous sorption of benzene and heavy metals onto two organoclays.  

PubMed

An experimental study was performed to determine the feasibility of using hexadecyltrimethylammonium bentonite clay (HDTMA-clay) and benzyltriethylammonium bentonite clay (BTEA-clay) for simultaneous sorption of benzene and one of four heavy metals (Pb, Cd, Zn and Hg). Specifically, the role of competition between benzene and each heavy metal was studied. The sorption of Pb, Cd, and Zn on both BTEA- and HDTMA-clay decreases in the presence of benzene relative to the sorption obtained without benzene present. This indicates that there is competition between Pb, Cd, and Zn and organic compounds during sorption onto both organoclays. On BTEA-clay, Cd, Pb and Zn sorption was reduced by 24, 37, and 51%, respectively. On HDTMA-clay, Cd, Pb, and Zn sorption was reduced by 25, 30, and 57%, respectively. Hg sorption was not affected either by the presence of benzene or by the organoclays used. The sorption of benzene onto BTEA-clay in the presence of Hg, Zn, Pb, and Cd was less than the sorption observed when no heavy metal was present. The presence of Hg resulted in the most significant decrease in sorption, causing a 59% reduction in benzene sorption. The presence of Zn, Pb, and Cd caused a 41, 35, and 31% reduction in benzene sorption, respectively. In general, sorption of benzene onto HDTMA-clay was not affected by the presence of the heavy metals, indicating there are no competitive effects observed with Zn, Cd, and Hg when HDTMA-clay was the sorbent. However, the presence of Pb did cause a 20% reduction in benzene sorption to HDTMA-clay. Both organoclays tested had dual sorptive properties for both heavy metals and an organic contaminant. While the competitive effects were greater for the BTEA clay, both organoclays are capable of simultaneously removing benzene and either Zn, Cd, Hg, or Pb from aqueous solution. PMID:17292377

Oyanedel-Craver, Vinka A; Fuller, Megan; Smith, James A

2007-05-15

296

Disposable cuvette test for enzymatic determination of heavy metals  

NASA Astrophysics Data System (ADS)

We report on an optical cuvette test for total heavy metals based on the inhibition of the enzyme urease by metals ions including silver(I), mercury(II), copper(II), nickel(II), cobalt(II), and cadmium(II). The enzymatic action is monitored using an optical ammonia transducer deposited on the wall of a disposable cuvette. This results in a rapid and inexpensive single-shot device for heavy metal sensing. A solution of urease and buffer is placed in the cuvette with the ammonium sensor membrane fixed on one of its walls. Enzymatic action starts after addition of a defined quantity of urea. This is indicated by the increase in the absorption of the ammonia sensor membrane whose color changes from yellow to blue. The slop of the increase in signal is the information for the un-inhibited reaction. After several minutes,the sample (containing the heavy metal) is added to the cuvette. Heavy metal ions inhibit the enzyme (by binding to the sulfhydryl groups) and cause a decrease in the slope. The ratio of slopes of un-inhibited and inhibited reactions is a direct parameter for detecting and calculating total heavy metals. The optimum pH was a trade-off between optimum enzyme activity (pH 7 at 25 degree(s)C) and the relative signal change of the ammonia-sensor (highest at pH 8). pH 7.5 was found to be optimal. The system was calibrated at optimized activities of urease (1.5 (mu) ) and an optimized urea concentration (0.5 mmol). Heavy metals inhibit in the following order: Ag(I) > Hg(II) > Cu(II) >> Ni(II) > Co(II) > Cd(II) > Fe(III) > Pb(II), Zn(II). The following concentrations that cause 50% inhibition were found: Ag(I) (0.1 ppm), Hg(II) (0.5 ppm), Cu(II) (0.5 ppm), Ni(II) (7 ppm), Co(II) (30 ppm), Cd(II) (95 ppm), Fe(III) (50 ppm), Zn(II) (85 ppm) and Pb(II) (210 ppm). We also studied the inhibitory effect of combinations of metal ions, the influence of ionic strength, and the effect of incubation time.

Wolfbeis, Otto S.; Preininger, Claudia

1995-10-01

297

Plasma polymer-functionalized silica particles for heavy metals removal.  

PubMed

Highly negatively charged particles were fabricated via an innovative plasma-assisted approach for the removal of heavy metal ions. Thiophene plasma polymerization was used to deposit sulfur-rich films onto silica particles followed by the introduction of oxidized sulfur functionalities, such as sulfonate and sulfonic acid, via water-plasma treatments. Surface chemistry analyses were conducted by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectroscopy. Electrokinetic measurements quantified the zeta potentials and isoelectric points (IEPs) of modified particles and indicated significant decreases of zeta potentials and IEPs upon plasma modification of particles. Plasma polymerized thiophene-coated particles treated with water plasma for 10 min exhibited an IEP of less than 3.5. The effectiveness of developed surfaces in the adsorption of heavy metal ions was demonstrated through copper (Cu) and zinc (Zn) removal experiments. The removal of metal ions was examined through changing initial pH of solution, removal time, and mass of particles. Increasing the water plasma treatment time to 20 min significantly increased the metal removal efficiency (MRE) of modified particles, whereas further increasing the plasma treatment time reduced the MRE due to the influence of an ablation mechanism. The developed particulate surfaces were capable of removing more than 96.7% of both Cu and Zn ions in 1 h. The combination of plasma polymerization and oxidative plasma treatment is an effective method for the fabrication of new adsorbents for the removal of heavy metals. PMID:25603034

Akhavan, Behnam; Jarvis, Karyn; Majewski, Peter

2015-02-25

298

A review of heavy metal adsorption by marine algae  

NASA Astrophysics Data System (ADS)

Accumulation of heavy metals by algae had been studied extensively for biomonitoring or bioremediation purposes. Having the advantages of low cost raw material, big adsorbing capacity, no secondary pollution, etc., algae may be used to treat industrial water containing heavy metals. The adsorption processes were carried out in two steps: rapid physical adsorption first, and then slow chemical adsorption. pH is the major factor influencing the adsorption. The Freundlich equation fitted very well the adsorption isotherms. The uptake decreased with increasing ionic strength. The principal mechanism of metallic cation sequestration involves the formation of complexes between a metal ion and functional groups on the surface or inside the porous structure of the biological material. The carboxyl groups of alginate play a major role in the complexation. Different species of algae and the algae of the same species may have different adsorption capacity. Their selection affinity for heavy metals was the major criterion for the screening of a biologic adsorbent to be used in water treatment. The surface complex formation model (SCFM) can solve the equilibrium and kinetic problems in the biosorption.

Jin-Fen, Pan; Rong-Gen, Lin; Li, Ma

2000-09-01

299

Trends and sources for heavy metals in urban atmosphere  

NASA Astrophysics Data System (ADS)

The concentrations of a number of heavy metals in the air in three Danish cities have been measured by means of PIXE for more than two decades. The well-known capability of PIXE for fast and efficient analysis of aerosol samples has been employed for analysis of daily samples from several sites during the whole period. The main sources are traffic, domestic heating and long-range transport. Source apportionment and trends for single metals are assessed by means of simple statistical methods. The most striking change has occurred for the Pb concentration, which is reduced by almost a factor of 100 following the reduction of the Pb content in petrol. The main source of Cu, Cr and Zn is the traffic. The concentrations of these elements have been slightly increasing. The concentrations for most of the other heavy metals, which originate mainly from sources outside the cities, have been decreasing.

Kemp, Kåre

2002-04-01

300

Heavy Metal Stress and Some Mechanisms of Plant Defense Response  

PubMed Central

Unprecedented bioaccumulation and biomagnification of heavy metals (HMs) in the environment have become a dilemma for all living organisms including plants. HMs at toxic levels have the capability to interact with several vital cellular biomolecules such as nuclear proteins and DNA, leading to excessive augmentation of reactive oxygen species (ROS). This would inflict serious morphological, metabolic, and physiological anomalies in plants ranging from chlorosis of shoot to lipid peroxidation and protein degradation. In response, plants are equipped with a repertoire of mechanisms to counteract heavy metal (HM) toxicity. The key elements of these are chelating metals by forming phytochelatins (PCs) or metallothioneins (MTs) metal complex at the intra- and intercellular level, which is followed by the removal of HM ions from sensitive sites or vacuolar sequestration of ligand-metal complex. Nonenzymatically synthesized compounds such as proline (Pro) are able to strengthen metal-detoxification capacity of intracellular antioxidant enzymes. Another important additive component of plant defense system is symbiotic association with arbuscular mycorrhizal (AM) fungi. AM can effectively immobilize HMs and reduce their uptake by host plants via binding metal ions to hyphal cell wall and excreting several extracellular biomolecules. Additionally, AM fungi can enhance activities of antioxidant defense machinery of plants. PMID:25688377

Emamverdian, Abolghassem; Ding, Yulong; Mokhberdoran, Farzad; Xie, Yinfeng

2015-01-01

301

The mediation of mutagenicity and clastogenicity of heavy metals by physicochemical factors  

Microsoft Academic Search

Heavy metals are an important class of environmental hazards, and as the use of heavy metals in industry continues to increase, larger segments of the biota, including human beings, will be exposed to increasing levels of these toxicants. Studies with microbes and representatives of the aquatic biota have shown that the toxicity of heavy metals is mediated by the physicochemical

H. Babich; M. A. Devanas; G. Stotzky

1985-01-01

302

Three profiles of heavy metal fans: A taste for sensation and a subculture of alienation  

Microsoft Academic Search

Profiles of three fans of heavy metal music are presented, in order to examine the definition and boundaries of the heavy metal subculture. It is suggested on the basis of these profiles that a high level of sensation seeking can lead to a liking for heavy metal music, because the music provides such high-intensity sensation. However, fans become part of

Jeffrey Arnett

1993-01-01

303

Heavy metals in organisms and sediments from Turkish Coast of the Black Sea, 1997–1998  

Microsoft Academic Search

During the period 1997–1998, macroalgae, sea snail, mussel, fish and sediment samples were collected at different stations of the Turkish Black Sea coast in order to establish the concentration of selected heavy metals. Heavy metals analyzed were Cd, Co, Cr, Ni, Zn, Fe, Mn, Pb and Cu. The results showed that the Turkish Black Sea coast is facing heavy metal

S Topcuo?lu; Ç K?rba?o?lu; N Güngör

2002-01-01

304

The Time Effect Research on Heavy Metal Elements Pollution of Urban Industrial Fire Coal  

Microsoft Academic Search

The heavy metal pollution made by industrial coal in city is receiving more and more attentions, but the time effect researches on fire coal capacity and heavy metal pollution after enterprise' relocation out of urban area are comparatively less. This paper studied the east Industrial zone, doing quantitative analysis on 5 types of heavy metal elements of coal samples, cinder,

Xiuhong Peng; Chengshi Qing; Bo Xu; Yongqin Ye; Shijun Ni; Hai Yang; Yuanwen Deng; Shishi Chen; Feng Cheng; Dong Yu; Jiangsu Zhang

2010-01-01

305

Simulated annealing and kriging method for identifying the spatial patterns and variability of soil heavy metal  

Microsoft Academic Search

Environmental data, including information regarding soil heavy metals, may contain significant uncertainty and exhibit a skewed distribution with a complex and unexplainable spatial variation. This study identified the spatial patterns and variations of soil heavy metals (Cu, Cd, Hg, and Pb) in the northern part of Changhua County in Taiwan to clarify the characteristics and pollution of soil heavy metals.

2000-01-01

306

Characteristics of Heavy Metal Pollution in the Soil around Lead-Zinc Mining Area  

Microsoft Academic Search

The environmental impact of heavy metal pollution from mining activities is of growing concern. Here we have carried out an environmental geochemical investigation to determine the concentrations of heavy metals (Cd, Pb, Zn, and Cu) in soils in and around lead-zinc mining and zinc smelting areas in Northeastern China, analyze the characteristics of heavy metal contamination and assess pollution level

Xiuyan Zhou; Zhe Zhao; Zhang Juanxia; Xiangxin Xue

2010-01-01

307

Colonization of heavy metal polluted soils by Collembola: preliminary1 experiments in compartmented boxes2  

E-print Network

1 Colonization of heavy metal polluted soils by Collembola: preliminary1 experiments;2 Keywords: Collembola, Acidophily, Heavy metals, Migration, Sensitivity.1 2 1. Introduction3 4 The sensitivity of Collembola (Hexapoda) to heavy metals has been the subject of recent5 investigations, pointing

Paris-Sud XI, Université de

308

Acute toxicity of lead, chromium, and other heavy metals to ciliates from activated sludge plants  

Microsoft Academic Search

Numerous papers deal with the occurrence of heavy metals in the various components of freshwater ecosystems and sewage treatment systems. However, few papers refer to the presence and effect of heavy metals in populations of aquatic cilated protozoa. In particular, the lethal concentrations (LC50) of heavy metals in ciliate populations that colonize the activated sludge or the biofilm of waste

P. Madoni; D. Davoli; G. Gorbi

1994-01-01

309

Soil Contamination and Plant Uptake of Heavy Metals at Polluted Sites in China  

Microsoft Academic Search

We investigated heavy metal contamination in soils and plants at polluted sites in China including some with heavy industries, metal mining, smelting and untreated wastewater irrigation areas. We report our main findings in this paper. The concentrations of heavy metals, including Cd and Zn, in the soils at the investigated sites were above the background levels, and generally exceeded the

Qing-Ren Wang; Yan-Shan Cui; Xiu-Mei Liu; Yi-Ting Dong; Peter Christie

2003-01-01

310

Chemical and Biological Parameters as Tools to Evaluate and Improve Heavy Metal Phytoremediation  

Microsoft Academic Search

In this review, chemical and biological parameters are discussed that strongly influence the speciation of heavy metals, their availability to biological systems and, consequently, the possibilities to use bioremediation as a cleanup tool for heavy metal polluted sites. In order to assess heavy metal availability, a need exists for rapid, cost-effective systems that reliably predict this parameter and, based on

Alexander A. Kamnev; Daniel van der Lelie

2000-01-01

311

Heavy Metal Phytoremediation from Aquatic Ecosystems with Special Reference to Macrophytes  

Microsoft Academic Search

The rapid pace of industrialization and urbanization has given birth to heavy metal pollution. Heavy metals are one of the most hazardous contaminants that may be present in the aquatic environment. It derives its origin from both natural and anthropogenic sources. Heavy metal pollution in aquatic ecosystem poses a serious threat to aquatic biodiversity, and drinking contaminated water poses severe

Prabhat Kumar Rai

2009-01-01

312

Ecological risk and pollution history of heavy metals in Nansha mangrove, South China.  

PubMed

Owing to the Industrial Revolution in the late 1970s, heavy metal pollution has been regarded as a serious threat to mangrove ecosystems in the region of the Pearl River Estuary, potentially affecting human health. The present study attempted to characterize the ecological risk of heavy metals (Cd, Cr, Cu, Mn, Ni, Pb and Zn) in Nansha mangrove, South China, by estimating their concentrations in the surface sediment. In addition, the pollution history of heavy metals was examined by determining the concentrations of heavy metals along the depth gradient. The phytoremediation potential of heavy metals by the dominant plants in Nansha mangrove, namely Sonneratia apetala and Cyperus malaccensis, was also studied. Results found that the surface sediment was severely contaminated with heavy metals, probably due to the discharge of industrial sewage into the Pearl River Estuary. Spatial variation of heavy metals was generally unobvious. The ecological risk of heavy metals was very high, largely due to Cd contamination. All heavy metals, except Mn, decreased with depth, indicating that heavy metal pollution has been deteriorating since 1979. Worse still, the dominant plants in Nansha mangrove had limited capability to remove the heavy metals from sediment. Therefore, we propose that immediate actions, such as regulation of discharge standards of industrial sewage, should be taken by the authorities concerned to mitigate the ecological risk posed by heavy metals. PMID:24675443

Wu, Qihang; Tam, Nora F Y; Leung, Jonathan Y S; Zhou, Xizhen; Fu, Jie; Yao, Bo; Huang, Xuexia; Xia, Lihua

2014-06-01

313

Heavy Metal Variations in Residential Soil Communities along an Urban to Rural Gradient  

E-print Network

Heavy Metal Variations in Residential Soil Communities along an Urban to Rural Gradient Christina P As Cd Pb Metals ppm Pre-1940 Post-1940 Spatial Variation Source: House Age Soil and Arthropod Heavy. Abstract Questions: 1) Do heavy metal concentrations (Cr, Ni, Cu, Zn, As, Cd and Pb) of residential soils

Hall, Sharon J.

314

HEAVY METALS IN THE NORTHERN FUR SEAL, CALLORHINUS URSIN US, AND  

E-print Network

HEAVY METALS IN THE NORTHERN FUR SEAL, CALLORHINUS URSIN US, AND HARBOR SEAL, PHOCA VITULINA of mercury were from southern California seals. Heavy metals are persistent contaminants that ultimately end resources, but some heavy metals are known to be harmful. One ppb (part pel' billion) of four commonly used

315

Macrobenthic Community in Tolo Harbour, Hong Kong and its Relations with Heavy Metals  

E-print Network

Macrobenthic Community in Tolo Harbour, Hong Kong and its Relations with Heavy Metals Kouping Chen study investigated the macrobenthic community in Tolo Harbour, Hong Kong, aiming at linking heavy metal and abun- dance of macrobenthos in areas with low heavy metal concentrations were recorded. Strong negative

Jiao, Jiu Jimmy

316

Trends in heavy metal concentrations in the Western and Central Baltic Sea waters detected by using  

E-print Network

Trends in heavy metal concentrations in the Western and Central Baltic Sea waters detected by using 2003; accepted 10 October 2003 Abstract Heavy metal concentrations from annual sampling in the period and the accumulation of, inter alia, heavy metals. At irregular intervals, major inflows provide large volumes

Dippner, Joachim W.

317

Independent Evolution of Heavy Metal-Associated Domains in Copper Chaperones and Copper-Transporting ATPases  

E-print Network

Independent Evolution of Heavy Metal-Associated Domains in Copper Chaperones and Copper and structure to the Cu- binding heavy metal-associated (HMA) domains of Cu- transporting ATPases (Cu to the Cu-binding heavy metal-associated (HMA) domains of Cu-transporting ATPases (Cu- ATPases) whose genes

Jordan, King

318

ORIGINAL ARTICLE Speciation and mobility of heavy metals in mud in coastal  

E-print Network

ORIGINAL ARTICLE Speciation and mobility of heavy metals in mud in coastal reclamation areas and the properties of the pore water in the mud may induce the release of some heavy metals into the mud. Field in different years indicate that most of the heavy metals in the mud decrease gradually with time

Jiao, Jiu Jimmy

319

A General Model for Kinetics of Heavy Metal Adsorption and Desorption on Soils  

E-print Network

A General Model for Kinetics of Heavy Metal Adsorption and Desorption on Soils Zhenqing Shi: In this study, we propose a general kinetics model for heavy metal adsorption and desorption reactions in soilsHs, and different flow rates. The kinetics model has been successfully applied to describe heavy metal adsorption

Sparks, Donald L.

320

ADVANCES IN BIOSORPTION OF HEAVY METALS David Kratochvil and Bohumil Volesky  

E-print Network

ADVANCES IN BIOSORPTION OF HEAVY METALS David Kratochvil and Bohumil Volesky Department of Chemical@chemeng.LAN.mcgill.ca SUMMARY Biosorption of heavy metals by various types of non-living (microbial) biomass appears as a very desorbing solutions facilitating a conventional follow-up metal recovery. ADVANCES IN BIOSORPTION OF HEAVY

Volesky, Bohumil

321

Characterization of sperm motility in sea bass: the effect of heavy metals and physicochemical  

E-print Network

Characterization of sperm motility in sea bass: the effect of heavy metals and physicochemical of several physicochemical variables and heavy metals on sperm swimming performance. Duration of sperm. Two of the heavy metals tested, Cu2þ and Pb2þ , did not affect sperm motility when the activating

Villefranche sur mer

322

Structural Basis for Heavy Metal Detoxification by an Atm1-Type  

E-print Network

Structural Basis for Heavy Metal Detoxification by an Atm1-Type ABC Exporter Jonas Y. Lee,1 Janet G), and plasma mem- branes (12). Other homologs have been impli- cated in heavy metal detoxification, including cadmium resistance by heavy metal tolerance factor­1 (HMT1) in Caenorhabditis elegans and Drosophila

Napp, Nils

323

Environmental Pollution (Series B) 6 (1983)309-318 Heavy Metals in the Centipede Lithobius variegatus  

E-print Network

Environmental Pollution (Series B) 6 (1983)309-318 Heavy Metals in the Centipede Lithobius) may accumulate considerable amounts of heavy metals. These authors have suggested that the high in this paper are, as far as is known, the first to be published on the concentrations of heavy metals

Hopkin, Steve

1983-01-01

324

ORIGINAL ARTICLE Spatio-temporal trends of heavy metals and source  

E-print Network

ORIGINAL ARTICLE Spatio-temporal trends of heavy metals and source apportionment in Tolo Harbour, Zn, As, Cd and Pb in bottom sediments of Tolo Harbour. The concentrations of the eight heavy metals. As, however, is not well correlated with the other seven heavy metals. The average concentrations

Jiao, Jiu Jimmy

325

Heavy Metal Stress. Activation of Distinct Mitogen-Activated Protein Kinase Pathways  

E-print Network

Heavy Metal Stress. Activation of Distinct Mitogen-Activated Protein Kinase Pathways by Copper, Vienna Biocenter, A­1030 Vienna, Austria Excessive amounts of heavy metals adversely affect plant growth and development. Whereas some regions naturally contain high levels of heavy metals, anthropogenic release

Hirt, Heribert

326

IMPACT OF HEAVY METALS IN SEWAGE SLUDGE ON SOIL AND PLANTS (COLZA and WHEAT)  

E-print Network

of heavy metals, however rape (colza) is a plant of the family Brassica napus, is an excellent bio of rape than wheat. Keywords: Mud, urban, industrial, heavy metals, rape, colza, wheat, bio accumulator is a small accumulator of heavy metals while rape is an accumulator of these elements. 45 hal-00788945

Paris-Sud XI, Université de

327

On the fate of heavy metals in municipal solid waste combustion Part I: devolatilisation of heavy metals on the grate  

Microsoft Academic Search

The aim of this study has been to investigate the chemistry and volatility of the heavy metals As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn on the grate of a MSW fired furnace, using equilibrium calculations. Focus has been on the influence of varying MSW composition and operational parameters such as air\\/fuel ratio and temperature. Equilibrium distributions at 950–1600

Lars Sørum; Flemming J. Frandsen; Johan E. Hustad

2003-01-01

328

Bacteria immobilisation on hydroxyapatite surface for heavy metals removal.  

PubMed

Selected bacterial strains were immobilised on the surface of hydroxyapatite (Ca10(PO4)6(OH)2 - HAp) of natural origin (fish bones). The capacity of the material, alone and in combination with the bacterial strains to act as heavy metal removers from aqueous streams was assessed. Pseudomonas fluorescens (S3X), Microbacterium oxydans (EC29) and Cupriavidus sp. (1C2) were chosen based on their resistance to heavy metals and capacity of adsorbing the metals. These systems were tested using solutions of Zn(II), Cd(II) and in solutions containing both metals. A synergistic effect between the strains and HAp, which is effective in removing the target heavy metals on its own, was observed, as the combination of HAp with the bacterial strains led to higher adsorption capacity for both elements. For the solutions containing only one metal the synergistic effect was greater for higher metal concentrations; 1C2 and EC29 were the most effective strains for Zn(II) and Cd(II) respectively, while S3X was less effective. Overall, an almost four-fold increase was observed for the maximum adsorption capacity for Zn(II) when 1C2 was employed - 0.433 mmol/g in comparison of 0.121 mmol/g for the unmodified HAp. For Cd(II), on the other hand, an almost three-fold increase was registered with EC29 bacterial strain - 0.090 vs 0.036 mmol/g for the unmodified HAp. When the solutions containing both metals were tested, the effect was more marked for lower concentrations. PMID:23524400

Piccirillo, C; Pereira, S I A; Marques, A P G C; Pullar, R C; Tobaldi, D M; Pintado, M E; Castro, P M L

2013-05-30

329

SULFIDE PRECIPITATION OF NICKEL AND OTHER HEAVY METALS FROM SINGLE- AND MULTI-METAL SYSTEMS  

EPA Science Inventory

Precipitation behavior of heavy metals (Ni, Co, Cd, Cu, and Zn) was studied extensively in single- and multi-metal systems. Kinetic studies showed that NiS oxidation (as a function of pH, oxygen, and reaction time) caused the dissolution of NiS. CoS precipitation would require hi...

330

Phytoremediation of heavy metals and study of the metal coordination by X-ray absorption spectroscopy  

Microsoft Academic Search

Although traditional technologies for cleaning contaminated soils and waters have proven to be efficient, they are usually expensive, labor intensive, and in the case of soil, they produce severe disturbance. More recently, the use of plants in metal extraction (phytoremediation) has appeared as a promising alternative in the removal of heavy metal excess from soil and water. Phytoremediation of polluted

Jorge L. Gardea-Torresdey; Jose R. Peralta-Videa; G. de la Rosa; J. G. Parsons

2005-01-01

331

Introducing a new metal accumulator plant and the evaluation of its ability in removing heavy metals  

Microsoft Academic Search

A field study was conducted in a dried waste pool of a lead (Pb) mine in Arak (Iran) to find the accumulator plant(s) and to evaluate the amount of metal bioaccumulation in the root and shoot portion of the naturally growing vegetation. Concentrations of heavy metals were determined both in the soil and the plants that were grown in the

Abdolkarim Chehregani; Fariba Mohsenzade; Froogh Vaezi

2009-01-01

332

Biomonitoring Heavy Metal Pollution with Lichens  

Microsoft Academic Search

\\u000a Certain characteristics of lichens and bryophytes meet the specifications required for biological monitors. These include\\u000a large geographical ranges, allowing the comparison of metal content in diverse regions, and a morphology that does not vary\\u000a with season, thus enabling accumulation to occur throughout the year (Puckett 1988). Lichens integrate long-term deposition patterns and do not reflect necessarily short-term patterns, measured by

Jacob Garty

333

Use of Power Plant Ash to Remove and Solidify Heavy Metals from a Metal-finishing Wastewater  

Microsoft Academic Search

This laboratory-scale study investigated initially the potential of heavy metal removal from a metal-finishing wastewater\\u000a using fly and bottom ash from a power plant as coagulants. It was found that the maximum heavy metal content in the ash–sludge\\u000a mix was obtained at a fly ash-to-bottom ash ratio of 1.5:1 and a stirring time of 3 h, which resulted in heavy metal

P. Fongsatitkul; P. Elefsiniotis; N. Khuhasawan; R. Jindal

2009-01-01

334

Botanical plants could rid soil of heavy metals  

SciTech Connect

A new technology that is now emerging holds promise of revolutionizing the remediation of soils contaminated with heavy metals. Called phytoremediation, it would use green plants to remove the metals. Plants take up the metals in their roots and translocate them to their shoots, which are harvested, burned in a kiln, and the metals recovered and recycled. The challenge is finding or engineering plants that can absorb, translocate, and tolerate heavy metals while producing enough foliage to make the process efficient. All plants take up small amounts of metals, he notes. What he looks for are weird plants that can accumulate them. Such plants exist, he says, giving credence to the feasibility of phytoremediation. Naturally occurring plants with spectacular metal uptake have been found growing on ore outcroppings, he explains. Cunningham scouts waste repositories and mining and industrial sites for metal-accumulating plant species. So far, he has identified two common weeds - hemp dogbane and ragweed - as candidates for remediating lead-contaminated soils. Both plants accumulate lead, he says, but their abilities vary across soils because lead exists in several forms in soil, and not all of its forms are easily absorbed. He finds that lowering the pH and the phosphate and sulfate content of the soil enhances uptake of the metal. The downside is these changes can impair the plant's nutritional environment. So, the chemistry of the soil must be carefully manipulated to boost metal uptake without losing plant biomass, he emphasizes. Cunningham's scheme is being field-tested at Chambers Works, a Due Pont facility in New Jersey. If ragweed proves to be the species of choice for remediating weapons sites and other lead-contaminated sites, he says allergy sufferers needn't worry. Only mutants of the weed that don't pollinate will be grown.

Brennan, M.

1993-04-20

335

Leachability of Arsenic and Heavy Metals from Mine Tailings of Abandoned Metal Mines  

PubMed Central

Mine tailings from an abandoned metal mine in Korea contained high concentrations of arsenic (As) and heavy metals [e.g., As: 67,336, Fe: 137,180, Cu: 764, Pb: 3,572, and Zn: 12,420 (mg/kg)]. US EPA method 6010 was an effective method for analyzing total arsenic and heavy metals concentrations. Arsenic in the mine tailings showed a high residual fraction of 89% by a sequential extraction. In Toxicity Characteristic Leaching Procedure (TCLP) and Korean Standard Leaching Test (KSLT), leaching concentrations of arsenic and heavy metals were very low [e.g., As (mg/L): 0.4 for TCLP and 0.2 for KSLT; cf. As criteria (mg/L): 5.0 for TCLP and 1.5 for KSLT]. PMID:20049231

Lim, Mihee; Han, Gi-Chun; Ahn, Ji-Whan; You, Kwang-Suk; Kim, Hyung-Seok

2009-01-01

336

Characterization of heavy metal particles embedded in tire dust.  

PubMed

Tire dust is a significant pollutant, especially as a source of zinc in the urban environment. This study characterizes the morphology and chemical composition of heavy metal particles embedded in tire dust and traffic-related materials (brake dust, yellow paint, and tire tread) as measured by a field emission scanning electron microscope equipped with an energy dispersive X-ray spectrometer (FESEM/EDX). In 60 samples of tire dust, we detected 2288 heavy metal particles, which we classified into four groups using cluster analysis according to the following typical elements: cluster 1: Fe, cluster 2: Cr/Pb, cluster 3: multiple elements (Ti, Cr, Fe, Cu, Zn, Sr, Y, Zr, Sn, Sb, Ba, La, Ce, Pb), cluster 4: ZnO. According to their morphologies and chemical compositions, the possible sources of each cluster were as follows: (1) brake dust (particles rich in Fe and with trace Cu, Sb, and Ba), (2) yellow paint (CrPbO(4) particles), (3) brake dust (particulate Ti, Fe, Cu, Sb, Zr, and Ba) and heavy minerals (Y, Zr, La, and Ce), (4) tire tread (zinc oxide). When the chemical composition of tire dust was compared to that of tire tread, the tire dust was found to have greater concentrations of heavy metal elements as well as mineral or asphalt pavement material characterized by Al, Si, and Ca. We conclude that tire dust consists not only of the debris from tire wear but also of assimilated heavy metal particles emitted from road traffic materials such as brake lining and road paint. PMID:15337346

Adachi, Kouji; Tainosho, Yoshiaki

2004-10-01

337

Heavy metals in garden soils along roads in Szeged, Hungary  

NASA Astrophysics Data System (ADS)

The soils of the urban environment, owing to the various anthropogenic activities, can be contaminated by heavy metals. The traffic is well-known for more decades to be main source of heavy metals mostly in cities. The accumulation of these elements can have different effects, either directly endangering the natural soil functions, or indirectly endangering the biosphere by bio-accumulation and inclusion in the food chain. The hobby gardens and the vegetable gardens directly along roads can be potential risky for people since unknown amount of heavy metals can be accumulated into organization of local residents due to consumption of vegetables and fruits grown in their own garden. The aim of this study was to determine the heavy metal content of garden soils directly along roads with heavy traffic in order to assess possible risk for human health. The total content and the mobile content of Cd, Co, Cr, Cu, Ni, Pb and Zn have been determined in samples from garden soils along 5 busy roads of Szeged, South Hungary. Enrichment factor has been calculated with the help of control soil samples far from roads. The soil properties basically influencing on metal mobility have also been examined. Finally, the human health risk of these garden soils has been modelled by determination of health risk quotient (HRQ). As a result of our investigations, it can be claimed that mostly Cu, Zn and to a lesser degree the Ni, Cr and Pb accumulated in garden soils along roads depending on the traffic density. In general, the topsoils (0-10 cm) had higher amount of these metals rather than the subsoils (40-50 cm). Ni of these metals has approached; Cu has exceeded limit value while Pb is under it. Cd is very high in both soils along roads and control ones far from roads. Garden soils along the roads have such basic soil parameters (pH, mechanical soil type, humus content) that prove fairly high metal-binding capacity for these soils. Total risk of usage of these gardens (ingestion of soil, dermal contact, consumption of vegetables) has not exceeded the moderate level in normal case. However, the degree of risk has considerably increased if you consume exclusively vegetables in contaminated garden soils. In this case the risk can be relatively high for the more sensitive children.

Szolnoki, Zsuzsanna; Farsang, Andrea

2010-05-01

338

Heavy metals in aquatic macrophytes drifting in a large river  

USGS Publications Warehouse

Macrophytes drifting through the water column in the Detroit River were collected monthly from May to October 1985 to estimate the quantities of heavy metals being transported to Lake Erie by the plants. Most macrophytes (80-92% by weight) drifted at the water surface. Live submersed macrophytes made up the bulk of each sample. The most widely distributed submersed macrophyte in the river, American wildcelery (Vallisneria americana), occurred most frequently in the drift. A total of 151 tonnes (ash-free dry weight) of macrophytes drifted out of the Detroit River from May to October. The drift was greatest (37 tonnes) in May. Concentrations of heavy metals were significantly higher in macrophytes drifiting in the river than in those growing elsewhere in unpolluted waters. Annually, a maximum of 2796 kg (eight heavy metals combined) were transported into Lake Erie by drifting macrophytes. The enrichment of all metals was remarkably high in macrophytes, relative to their concentration in water of the Detroit River. Detroit River Macrophytes are thus a source of contaminated food for animals in the river and in Lake Erie.

Manny, Bruce A.; Nichols, Susan J.; Schloesser, Donald W.

1991-01-01

339

Diazotrophs-assisted phytoremediation of heavy metals: a novel approach.  

PubMed

Heavy metals, which have severe toxic effects on plants, animals, and human health, are serious pollutants of the modern world. Remediation of heavy metal pollution is utmost necessary. Among different approaches used for such remediation, phytoremediation is an emerging technology. Research is in progress to enhance the efficiency of this plant-based technology. In this regard, the role of rhizospheric and symbiotic microorganisms is important. It was assessed by enumeration of data from the current studies that efficiency of phytoremediation can be enhanced by assisting with diazotrophs. These bacteria are very beneficial because they bring metals to more bioavailable form by the processes of methylation, chelation, leaching, and redox reactions and the production of siderophores. Diazotrophs also posses growth-promoting traits including nitrogen fixation, phosphorous solubilization, phytohormones synthesis, siderophore production, and synthesis of ACC-deaminase which may facilitate plant growth and increase plant biomass, in turn facilitating phytoremediation technology. Thus, the aim of this review is to highlight the potential of diazotrophs in assisting phytoremediation of heavy metals in contaminated soils. The novel current assessment of literature suggests the winning combination of diazotroph with phytoremediation technology. PMID:25339525

Ullah, Abid; Mushtaq, Hafsa; Ali, Hazrat; Munis, Muhammad Farooq Hussain; Javed, Muhammad Tariq; Chaudhary, Hassan Javed

2015-02-01

340

Immobilization of heavy metals and phenol on altered bituminous coals  

SciTech Connect

This article evaluates adsorption ability of the altered bituminous coals to remove heavy metals and/or phenol from aqueous solutions. As for heavy metals, copper (II), cadmium (II) and lead (II) cations were used. In addition to phenol, cyclohexanol and 2-cyclohexen-1-ol were also examined. Adsorption experiments were conducted in the batch mode at room temperature and at pH 3 and 5. To characterize the texture of coal samples, adsorption isotherms of nitrogen at - 196{sup o}C, enthalpies of the immersion in water, and pH values in aqueous dispersions were measured. Coal hydrogen aromaticities were evaluated from the infrared spectrometric examinations (DRIFTS). Based on the investigations performed, cation exchange was confirmed as the principal mechanism to immobilize heavy metallic ions on coals. However, apart from carboxylic groups, other functionalities (hydroxyl groups) were found to be involved in the adsorption process. During adsorption of phenol, {pi}-{pi} interactions between {pi}-electrons of phenol and aromatic rings of coal proved to play the important role; however, no distinct correlation between adsorption capacities for phenol and hydrogen aromaticities of the coal was found. Probable involvement of oxygenated surface groups in the immobilization of phenol on coal was deduced. As a result, for waste water treatment, oxidative altered bituminous coal can be recommended as a suitable precursor, with the largest immobilization capacities both for metallic ions and phenol, as found in the studied samples.

Taraba, B.; Marsalek, R. [Technical University of Ostrava, Ostrava (Czech Republic). Dept. of Chemistry

2007-07-01

341

Sewage sludge effects on soil: heavy metal accumulation and movement  

SciTech Connect

Treated municipal sewage sludge at 0, 11.2, 33.6, and 67.2 metric tons/ha was applied each year for two consecutive years and incorporated into a Byler loam soil (Typic Fragiudalf) having an initial pH of 5.6. Sorghum (Sorghum vulgare L.) was grown in replicated plots (6.1m x 4.6m). Soil samples were taken at 0 to 20 cm and 20 to 40 cm depth at the end of each year and analyzed for DTPA-extractable Cu, Zn, Cd, and Ni. Surface soil exhibited significant increases in heavy metal concentrations in the first year at the 67.2 metric tons/ha rates. Heavy metal concentrations increased with continued sludge application. However, this increase was not in proportion to the amount of sludge applied, suggesting some immobilization of metals with time. After two years, downward movement and significiant increases in Cu, Zn, and Ni levels were noted at the 20 to 40 cm depth at the higher rates. Heavy metal levels in the surface soil did not appear to be phytotoxic as judged from sorghum grain and dry matter yields and comparisons with other similar studies. Sludge applications had little effect on soil pH.

Taylor, R.W.; Duseja, D.R.; Thangudu, P.R.

1982-01-01

342

[Bioaccumulation of sediment heavy metals in Bellamya aeruginosa and its relations with the metals geochemical fractions].  

PubMed

A 28-day sediment bioaccumulation test was conducted to study the bioaccumulation of river sediment heavy metals in Bellamya aeruginosa, and its relations with the geochemical fractions of the metals. A higher bioaccumulation of Cd, Pb, Cu, Cr, Zn, and Mn was found in the hepatopancreas of B. aeruginosa, with the greatest accumulation of Zn (84.32% +/- 4.36%), followed by Cu (7.67% +/- 2.84%), Pb (3.62% +/- 1.84%), Cr (2.22% +/- 1.03%), Mn (1.33% +/- 0.15%), and Cd (0.83% +/- 0.53%). No significant correlations were observed between the heavy metals accumulations in B. aeruginosa hepatopancreas, but the significant positive correlation between the metals pollution index of hepatopancreas and the Nemerow pollution index of sediments suggested that B. aeruginosa could be used as a potential bioindicator for sediment heavy metals pollution. The biota-sediment accumulation factors (BSAFs) for Cd, Cr, Zn, and Mn from different sediments showed a higher variability, while the BSAFs for Cu and Pb were relatively constant. The bioaccumulation of Cd had significant correlations with exchangeable Cd, weak acid soluble Cd, and oxidizable Cd; Pb bioaccumulation had significant correlation with reducible Pb; Cu bioaccumulation had significant correlation with oxidizable Cu; while Cr and Mn bioaccumulation had no correlations with the total concentrations and geochemical fractions of the two metals. Therefore, it would be inappropriate to use the BSAF as the indicator for the bioaccumulation of heavy metals in B. aeruginosa. PMID:20560332

Ma, Tao-Wu; Zhu, Cheng; Wang, Gui-Yan; Zhou, Ke; Peng, Jin-Ying; Liu, Jia

2010-03-01

343

Plants accumulating heavy metals in the Danube River wetlands  

PubMed Central

Background We present herein our results regarding the accumulation of four heavy metals (copper, cadmium, lead, and zinc) in four aquatic species plants (Ceratophyllum demersum, Potamogeton pectinatus, Potamogeton lucens, Potamogeton perfoliatus) collected from the Danube River, South-Western part of Romania and their possible use as indicators of aquatic ecosystems pollution with heavy metals. Methods Elements concentration from the vegetal material was determined through Inductively Coupled Plasma – Mass Spectrometry. Results The species were chosen based on their previous use as bioindicators in aquatic ecosystems and due to the fact they are one of the most frequent aquatic plant species of the Danube River ecosystems within the Iron Gates Natural Park. Highest amounts are recorded for Ceratophyllum demersum (3.52 ?g/g for Cd; 22.71 ?g/g for Cu; 20.06 ?g/g for Pb; 104.23 ?g/g for Zn). Among the Potamogeton species, the highest amounts of heavy metals are recorded in Potamogeton perfoliatus (1.88 ?g/g for Cd; 13.14 ?g/g for Cu; 13.32 ?g/g for Pb; 57.96 ?g/g for Zn). The sequence for the bioconcentration factors (BCFs) calculated in order to describe the accumulation of the four metals is Cd >> Zn > Pb > Cu. Increase of the zinc concentration determines an increase of the cadmium concentration (Spearman rho=0.40, p=0.02). Conclusions Despite the low ambiental levels of heavy metals, the four aquatic plants have the ability to accumulate significant amounts, which make them useful as biological indicators. BCF value for Ceratophyllum demersum indicated this species as a cadmium hyperaccumulator. PMID:24359799

2013-01-01

344

Sorption of heavy metals to Phormidium laminosum biomass  

SciTech Connect

The capacity to adsorb a number of heavy metals [Fe(II), Cr(III), Cd(II), Pb(II), Zn(II), Cu(II) and Ni(II)] by heat-dried biomass of the non-N{sub 2}-fixing cyanobacterium Phormidium laminosum was examined. Pretreatment of biomass with alkaline (1 M NaOH or Na{sub 2}CO{sub 3}) washes led to increased metal adsorption, whereas acid treatment was inadequate. Exopolysaccharides present in the mucilaginous layer covering nitrogen-starved cells did not improve the adsorption capacity of the biomass. Biosorption was a very fast and pH-dependent process for most metals investigated. Generally, binding showed a minimum at pH < 3, but increased clearly with pH and reached a maximum at about pH 6-7. In contrast, the amount of metal bound increased with the biomass and the amount of available metal. Constants from Langmuir isotherms were calculated and the order of relative affinities for the studied metals was established according to the sorption intensity. Far from being reduced, the biosorption of the tested metals, with the exception of Ni(II), was slightly enhanced in the presence of high concentrations of Ca{sup 2+} (up to 200 p.p.m.). Finally, desorption attempts with 0.1 M H{sub 2}SO{sub 4} succeeded to different degrees depending on the metal. Alkaline conditioned biomass of P. laminosum can constitute an interesting and novel biosorbent of heavy metals to depollute wastewaters, even in hard waters containing a high concentration of Ca{sup 2+}. 38 refs., 5 figs., 2 tabs.

Sampedro, M.A.; Blanco, A.; Llama, M.J.; Serra, J.L. [Universidad del Pais Vasco, Bilbao (Spain)

1995-12-01

345

[Antimony and other heavy metals in metallic kitchen ware].  

PubMed

The antimony in metallic kitchen ware was determined. The content of this element in metals used for the production or repairing of utensils, containers and packaging which come in contact with foods is regulated and should be less than 5% in under the Japanese Food Sanitation Law. In eight metallic samples, antimony was detected in solder used for the production of a can for green tea and an eggbeater. The contents were 1.30% in the former and 1.90% in the latter. No antimony was detected in solder used for a cookie cutter. A sample of solder used for electric work, not for food utensils, contained 0.81% of antimony. In other metallic utensils which come in contact with food such as aluminum foil, a brass spoon, a stainless steel fork, a wire netting, and an iron rock for vegetable color stabilizing, antimony was not detected at a 0.05% detection limit. A qualitative test using rhodamine B also showed positive results in only three solder samples. Lead concentrations in solder used for the kitchen ware were from 39.3 to 51.3%. These concentrations were higher than the limit (20%) of lead content by the Law. No cadmium was detected in any samples. PMID:2636916

Ishiwata, H; Sugita, T; Yoshihira, K

1989-01-01

346

Unveiling Satan's Wrath: Aesthetics and Ideology in AntiChristian Heavy Metal  

Microsoft Academic Search

Unlike many heavy metal bands that utilize blasphemy, sacrilege, and evil images for superficial shock value, the wrath of anti-Christian heavy metal bands is rooted in authentic sources. The anti-Christian aesthetic within the Black Metal and impious Death Metal scenes derives from the ideology of popular satanism and the subordinate structural position of the scene. In addition to the defiance

Jonathan Cordero

347

ACCUMULATION AND CELLULAR EFFECTS OF HEAVY METALS IN BENTHIC AND PLANKTONIC ALGAE  

EPA Science Inventory

These results suggest that in addition to metal exclusion, two other mechanisms are responsible for successful adaptation to heavy metals in Great Lakes algae. Heavy metals, especially Pb, Cd, and Zn can be incorporated in polyphosphate bodies. Metals incorporated in this manner ...

348

Effects of heavy metals on antioxidant activities of Atriplex hortensis and A. rosea  

Microsoft Academic Search

Oxidative stress is induced by a wide range of environmental factors including heavy metals stress. Therefore, antioxidant resistance mechanisms may provide a strategy to enhance metal tolerance, and processes underlying antioxidant responses to metal stress must be clearly understood. In the present study, the effects of heavy metals generating antioxidative defense systems (i.e. superoxide dismutase, ascorbate peroxydase, glutathione reductase and

S. Sai Kachout; A. Ben Mansoura; J. C. Leclerc; R. Mechergui; M. N. Rejeb; Z. Ouerghi

349

Photoelectron spectroscopy of group IV heavy metal dimers: Sn;, Pb;, and SnPb-  

E-print Network

Photoelectron spectroscopy of group IV heavy metal dimers: Sn;, Pb;, and SnPb- Joe Ho, Mark L The group IV heavy metal dimers Sn, and Pb, have attracted extensiveattention due to their interesting elec states, anionic electronic ground states,and the nature of the metal-metal bond of these dimersis far

Lineberger, W. Carl

350

Derivation and application of a new model for heavy metal biosorption by algae  

Microsoft Academic Search

An equilibrium model for describing the relationships between important parameters for heavy metal sorption by algae was derived through a thermodynamics approach. In this model, both the removal efficiency of heavy metal and metal adsorption per unit algal biomass are considered to be simple functions of the ratio of algal biomass concentration to the initial metal concentration for selected conditions,

Karina Yew-Hoong Gin; Ying-Zhong Tang; M. A. Aziz

2002-01-01

351

Humic acid-inspired hybrid materials as heavy metal absorbents.  

PubMed

Three SiO(2)-based materials were prepared via covalent immobilization of carboxyl groups (COOH), phenolic groups (GA), or humic acid on an SiO(2) surface. Their sorbing properties were evaluated for removal of heavy metals (Pb(2+), Cd(2+), Cu(2+), Zn(2+), and Mg(2+)) from aqueous solution. The data show a significant improvement for metal uptake, compared to unmodified silica that can be attributed to the adsorption of metals to the deprotonated form of functional groups (COOH, GA, HA). The metal-uptake capacity of the SiO(2)-HA material was 10 times higher that those of the other two materials. The present data provide direct experimental proof that HA can be viewed and modeled as a combination of -COO and R-OH functional groups. PMID:20705298

Stathi, Panagiota; Deligiannakis, Yiannis

2010-11-01

352

Wetland plants as indicators of heavy metal contamination.  

PubMed

In this study metal accumulating abilities of three emergent macrophytes (Phragmites australis, Typha capensis and Spartina maritima) were investigated in the urbanised Swartkops Estuary. Plants and sediment samples were collected at seven sites along the banks of the main channel and in adjacent canals. Sediments and plant organs were analysed, by means of atomic absorption spectrometry, for four elements (Cd, Cu, Pb, and Zn). Metal concentrations in the sediments of adjacent canals were found to be substantially higher than those at sites along the banks of the estuary. These differences were reflected in the plant organs for Pb and Zn, but not for Cu and Cd. All three species exhibited significantly higher concentrations of metals in their roots. These species are therefore suitable for use as indicators of the presence and level of heavy metal contaminants in estuaries. PMID:25599629

Phillips, D P; Human, L R D; Adams, J B

2015-03-15

353

Heavy metal transport in the hindon river basin, India.  

PubMed

Total mass transfers of heavy metal in dissolved and particulate form has been determined in the downstream section of river Hindon, an important tributary of river Yamuna (India). The contribution of different point sources to the river Hindon has also been assessed. The river Kali has the largest contribution to the river Hindon. The highest metal loads were related to the highest flow of the river and thereby increased both by surface runoff and sediment resuspension. The contribution of monsoon months to the total transported load was also calculated and it was observed that monsoon months contributes more than 40% of total loading annually for all the metals. The metal fluxes from the river Hindon were compared with other rivers of Indian sub-continent. PMID:16404544

Jain, C K; Sharma, M K

2006-01-01

354

Salinity-heavy metal interactions as evaluated by soil extraction and plant analysis  

SciTech Connect

Both heavy metal pollution and saline water irrigation are increasing in the dry areas, especially in developing countries. The effects of soil and water salinity on the transfer of heavy metals to crops are, however, not well understood. The uptake of Zn, Cu and Cd from a polluted desert soil from the north west of Egypt was therefore evaluated in pot experiments with maize, irrigated either with NaCl or with NaCl + CaCl{sub 2} solutions. NaCl accelerated root mortality and increased both the concentration of heavy metals in soil saturation extract and their uptake of heavy metals differently. While the solubility of heavy metals was enhanced by CaCl{sub 2}, both root mortality and the uptake of heavy metals were depressed. It was concluded that salinity of irrigation water affects heavy metal uptake at least partly by modifying root functions. 12 refs., 4 tabs.

Helal, H.M.; Haque, S.A.; Ramadan, A.B.; Schnug, E. [Institute of Plant Nutrition and Soil Science, Braunschweig (Germany)

1996-12-31

355

Role of soil rhizobacteria in phytoremediation of heavy metal contaminated soils*  

PubMed Central

Heavy metal pollution of soil is a significant environmental problem and has its negative impact on human health and agriculture. Rhizosphere, as an important interface of soil and plant, plays a significant role in phytoremediation of contaminated soil by heavy metals, in which, microbial populations are known to affect heavy metal mobility and availability to the plant through release of chelating agents, acidification, phosphate solubilization and redox changes, and therefore, have potential to enhance phytoremediation processes. Phytoremediation strategies with appropriate heavy metal-adapted rhizobacteria have received more and more attention. This article paper reviews some recent advances in effect and significance of rhizobacteria in phytoremediation of heavy metal contaminated soils. There is also a need to improve our understanding of the mechanisms involved in the transfer and mobilization of heavy metals by rhizobacteria and to conduct research on the selection of microbial isolates from rhizosphere of plants growing on heavy metal contaminated soils for specific restoration programmes. PMID:17323432

Jing, Yan-de; He, Zhen-li; Yang, Xiao-e

2007-01-01

356

Sublethal Heavy Metal Stress Stimulates Innate Immunity in Tomato  

PubMed Central

Effect of sublethal heavy metal stress as plant biotic elicitor for triggering innate immunity in tomato plant was investigated. Copper in in vivo condition induced accumulation of defense enzymes like peroxidase (PO), polyphenol oxidase (PPO), phenylalanine ammonia-lyase (PAL), and ?-1,3 glucanase along with higher accumulation of total phenol, antioxidative enzymes (catalase and ascorbate peroxidase), and total chlorophyll content. Furthermore, the treatment also induced nitric oxide (NO) production which was confirmed by realtime visualization of NO burst using a fluorescent probe 4,5-diaminofluorescein diacetate (DAF-2DA) and spectrophotometric analysis. The result suggested that the sublethal dose of heavy metal can induce an array of plant defense responses that lead to the improvement of innate immunity in plants. PMID:25729768

Chandra, Swarnendu; Acharya, Krishnendu

2015-01-01

357

Heavy metals in Ras Beirut prawns and sea urchin eggs.  

PubMed

Whole samples of Palaemon elegans Rathke, 1837 and eggs of Paracentrotus lividus Lamarck, 1816 were collected on the coast of Ras Beirut, Lebanon in the summer and fall of 1977 and the spring of 1978. All were analysed for lead, cadmium, copper and other heavy metals. Lead concentrations in both the prawns and sea urchin eggs appeared to be highest in the summer and lowest in the spring, whereas cadmium was low in all seasons with only a few elevated readings. The strongest tendency towards seasonal variation was seen in the copper levels of the prawns, which were high in summer, much lower in fall, and then high again in spring. Results of the analyses for nickel, iron, zinc and chromium are also discussed. Of the various possible sources of heavy metals in the Ras Beirut coastal area, untreated sewage, pesticide residues, and automobile exhaust are the most important. PMID:429762

Shiber, J G

1979-01-01

358

Situ formation of apatite for sequestering radionuclides and heavy metals  

DOEpatents

Methods for in situ formation in soil of a permeable reactive barrier or zone comprising a phosphate precipitate, such as apatite or hydroxyapatite, which is capable of selectively trapping and removing radionuclides and heavy metal contaminants from the soil, while allowing water or other compounds to pass through. A preparation of a phosphate reagent and a chelated calcium reagent is mixed aboveground and injected into the soil. Subsequently, the chelated calcium reagent biodegrades and slowly releases free calcium. The free calcium reacts with the phosphate reagent to form a phosphate precipitate. Under the proper chemical conditions, apatite or hydroxyapatite can form. Radionuclide and heavy metal contaminants, including lead, strontium, lanthanides, and uranium are then selectively sequestered by sorbing them onto the phosphate precipitate. A reducing agent can be added for reduction and selective sequestration of technetium or selenium contaminants.

Moore, Robert C. (Edgewood, NM)

2003-07-15

359

The adsorption behavior of heavy metals on anionic surfactant micelles  

SciTech Connect

The adsorption behaviors of monovalent metal ion (Na) and divalent metal ions (Cu, Cd and Pb,) on micelles composed of the anionic surfactant, dodecylsulfate (DS{sup {minus}}) were investigated in ultrafiltration experiments in this study. The anionic surfactant molecule consists of a polar moiety with negative charge and a nonpolar moiety with neutral charge. As the surfactant concentration is greater than the critical micelle concentration (cmc), a surfactant molecule will aggregate with other surfactant molecules to form micelles which surfaces are surrounded with negative charges. Due to columbic attraction, the heavy metals will be adsorbed on the micelle surface. The experimental results indicate that the anionic micelles have a higher affinity for divalent species than for the monovalent specie. However, a high concentration of Na{sup +} competes for surface area diminishing the ability of the DS{sup {minus}} to adsorb either divalent species. At experimental conditions from 0 to 100 mM NaCl addition, the percentage of Na, Cu, Cd and Pb, adsorbed on micelle surface are 17.4{approximately}3.7%, 77.8{approximately}31.1%, 85.7{approximately}10.0% and 83.4{approximately}19.4%, respectively. The results show that the removal of heavy metals by anionic surfactant micelles is practical as fewer monovalent metals are exists.

Yuan, C.; Hung, C.H.

1999-07-01

360

Heavy metals in an urban watershed in southeastern Michigan.  

PubMed

The occurrence of heavy metals in the soil was measured over a period of several years to determine background concentrations in a heavily urbanized watershed in southeastern Michigan. A spatially dispersed sample was collected to capture the inherent variability of the soils and historic land use. The analysis focused on 14 metals (antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, thallium, and zinc) that are part of the USEPA's list of the 129 most common pollutants. Metal concentrations were measured at three depths: near-surface (<0.5 m), shallow subsurface (0.5-10 m), and depths greater than 10 m across six soil units in glacial terrain. Additional analyses assessed the metal concentrations in each depth profile across three general land use categories: residential, commercial, and industrial. Metal concentrations were the highest in the near-surface with Pb present at concentrations averaging 15.5 times that of background in industrial areas and approximately 16 times background in residential areas. Cadmium, Hg, and Zn were also present in surface soils at levels of several times that of background. The highest concentrations of each of these metals were present in the clay-rich soils located in the eastern, more urbanized and industrialized part of the watershed. Metals detected at elevated concentrations decreased in concentration with increasing depth and distance from the urbanized and industrialized center of the watershed. Statistically significant differences in the concentrations of heavy metals were also noted between the land use categories, with Cd, Cr, Cu, Pb, Ni, and Zn observed within industrial areas at mean concentrations several times greater than background levels. PMID:14964371

Murray, Kent S; Rogers, Daniel T; Kaufman, Martin M

2004-01-01

361

Heavy Metal Toxicity: Effect on Plant Growth and Metal Uptake by Wheat, and on Free Living Azotobacter  

Microsoft Academic Search

A pot study was conducted to investigate the toxiceffects of certain heavy metals on the plant growth and grainyield of wheat (Triticum aestivum L.). The resultsrevealed that heavy metals brought about significant reductionsin both parameters, Cd being the most toxic metal followed by Cu,Ni, Zn, Pb and Cr. Moreover, the presence of Cd in the soilresulted in the maximum inhibition

Rana Athar; Masood Ahmad

2002-01-01

362

Acid mine drainage and heavy metal contamination in groundwater of metal sulfide mine at arid territory (BS mine, Western Australia)  

Microsoft Academic Search

The issues of acid mine drainage (AMD) and heavy metals contamination in the metal sulfide mine in the arid district were explored, through studying the acidification and the heavy metals distribution and evolution of groundwater in the black swan (BS) nickel sulfide mine (Western Australia). The groundwater samples were collected from the drilling holes situated in the vicinity of tailings

Liang-qi LEI; Ci-an SONG; Xiang-li XIE; Yan-hong LI; Fei WANG

2010-01-01

363

Heavy metal poisoning: the effects of cadmium on the kidney  

Microsoft Academic Search

The heavy metal cadmium (Cd) is known to be a widespread environmental contaminant and a potential toxin that may adversely\\u000a affect human health. Exposure is largely via the respiratory or gastrointestinal tracts; important non-industrial sources\\u000a of exposure are cigarette smoke and food (from contaminated soil and water). The kidney is the main organ affected by chronic\\u000a Cd exposure and toxicity.

Nikhil JohriGregory Jacquillet; Grégory Jacquillet; Robert Unwin

2010-01-01

364

Heavy metals in source-separated compost and digestates.  

PubMed

The production of compost and digestate from source-separated organic residues is well established in Europe. However, these products may be a source of pollutants when applied to soils. In order to assess this issue, composts, solid and liquid digestates from Switzerland were analyzed for heavy metals (Cd, Co, Cr, Cu, Ni, Pb and Zn) addressing factors which may influence the concentration levels: the treatment process, the composition, origin, particle size and impurity content of input materials, the season of input materials collection or the degree of organic matter degradation. Composts (n=81) showed mean contents being at 60% or less of the legal threshold values. Solid digestates (n=20) had 20-50% lower values for Cd, Co, Pb and Zn but similar values for Cr, Cu and Ni. Liquid digestates (n=5) exhibited mean concentrations which were approximately twice the values measured in compost for most elements. Statistical analyses did not reveal clear relationships between influencing factors and heavy metal contents. This suggests that the contamination was rather driven by factors not addressed in the present study. According to mass balance calculations related to Switzerland, the annual loads to agricultural soils resulting from the application of compost and digestates ranged between 2% (Cd) and 22% (Pb) of total heavy metal loads. At regional scale, composts and digestates are therefore minor sources of pollution compared to manure (Co, Cu, Ni, Zn), mineral fertilizer (Cd, Cr) and aerial deposition (Pb). However, for individual fields, fertilization with compost or digestates results in higher heavy metal loads than application of equivalent nutrient inputs through manure or mineral fertilizer. PMID:24613591

Kupper, Thomas; Bürge, Diane; Bachmann, Hans Jörg; Güsewell, Sabine; Mayer, Jochen

2014-05-01

365

Alginate Properties and Heavy Metal Biosorption by Marine Algae  

Microsoft Academic Search

The physical properties of the alginate component in four different brown seaweeds (Sargassumfluitans, Ascophyllum nodosum, Fucus vesiculo-sus, andLaminaria japonica) were characterized using potentiometric titration,13C-nuclear magnetic resonance (NMR), chemical analysis, and viscosity measurements. The heavy metal binding capacities of the\\u000a corresponding seaweeds were directly proportional to their respective total carboxyl group content, and related to the electronegativity\\u000a of the elements investigated

Eric Fourest; Bohumil Volesky

1997-01-01

366

Effects of Gravity on Processing Heavy Metal Fluoride Fibers  

NASA Technical Reports Server (NTRS)

The effects of gravity on the crystal nucleation of heavy metal fluoride fibers have been studied in preliminary experiments utilizing NASA's KC-135 reduced gravity aircraft and a microgravity sounding rocket flight. Commercially produced fibers were heated to the crystallization temperature in normal and reduced gravity. The fibers processed in normal gravity showed complete crystallization while the fibers processed in reduced gravity did not show signs of crystallization.

Tucker, Dennis S.; Workman, Gary L.; Smith, Guy A.

1997-01-01

367

Bioindication of Heavy Metals in Soil by Liverworts  

Microsoft Academic Search

.   Studies were made of the accumulation of the heavy metals Ba, Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb, Sr, V, and Zn and the macroelements\\u000a N, P, K, Ca, and Mg in liverworts Conocephalum conicum, Marchantia polymorphia, and Pellia epiphylla collected from 57 microhabitats in Poland (Lower Silesia, Tatry Mts., and Puszcza Augustowska forest) and one microhabitat\\u000a in

A. Samecka-Cymerman; A. Marczonek; A. J. Kempers

1997-01-01

368

Chemical changes in heavy metals in the leachates from Technosols.  

PubMed

A 2 month long column study was conducted to evaluate the mobility of heavy metals eluting from Technosols constituted from sewage sludges (aerobic or anaerobic) (as controls) or a mixture of different types of sewage sludges with green foundry sand (FS) or/and Linz-Donowitz slag (LD). The organic and inorganic wastes were mixed at a ratio of 56:44 (w/w). The mixtures and the controls were moistened to field capacity before adding them to the polypropylene columns (4.5 cm wide and 14 cm long). During the 8-week experimental period, the columns were watered, twice a week, with 100 mL of deionised water. The concentrations of heavy metals (Cu, Zn, Ni, Pb, Cd, and Cr) in the leachates were determined periodically. The concentrations of all the heavy metals were generally higher in the leachates from the Technosols containing anaerobic sewage sludge as a component. The concentration of Cu was strongly dependent on pH and was significantly higher (P<0.05) in the most alkaline leachates (pH>10) than in the other leachates. More Zn was mobilized in the most acidic leachates (pH<6) than in other leachates. The concentration of Ni in 80% of the leachates exceeded the EU drinking water limit for Ni (0.02 mgL(-1)). The concentrations of Pb were lower in the Technosols containing FS. The concentrations of Cd in the leachates from Technosols containing the conditioners were relatively high, while concentrations of Cr were higher in the controls. As far as the potential toxicity of heavy metals is concerned, the combination of aerobic sludge, inorganic conditioners able to buffer the pH to around neutrality, and reactive aluminosilicates, can be regarded as suitable choice for formulating Technosols from wastes. PMID:19580987

Yao, F X; Macías, F; Virgel, S; Blanco, F; Jiang, X; Camps Arbestain, M

2009-09-01

369

Algae sequester heavy metals via synthesis of phytochelatin complexes  

Microsoft Academic Search

A Cd-binding complex was isolated from Chlorella fusca and has been shown to be composed of phytochelating peptides, (?-Glu-Cys)n-Gly, n=2–5. Members of six of the ten classes of Phycophyta revealed phytochelatin synthesis after exposure to cadmium ions. Phytochelatin was also induced by ions of lead, zinc, silver, copper and mercury. These experiments uneqiovocally demonstrated that algae sequester heavy metals by

Walter Gekeler; Erwin Grill; Ernst-Ludwig Winnacker; Meinhart H. Zenk

1988-01-01

370

Micellar enhanced ultrafiltration of heavy metals using lecithin  

E-print Network

and costly. Micellar Enhanced Ultrafiltration (MEUF), which combines the advantages of both reverse osmosis and ultrafiltration, has been shown effective in the treatment of aqueous wastes for heavy metals with the use of synthetic surfactants.... These macromolecules will consist of an Figure 3. Micette Structure in Aqueous Solution often typical number of monomers, called an aggregation number. A micelle composed of ionic surfactants is highly charged. Due to electrostatic forces, these micelles...

Ahmadi, Saman Nameghi

1992-01-01

371

Effect of fertilizer application on soil heavy metal concentration  

Microsoft Academic Search

A large amount of chemicals is annually applied at the agricultural soils as fertilizers and pesticides. Such applications\\u000a may result in the increase of heavy metals particularly Cd, Pb, and As. The objective of this study was to investigate the\\u000a variability of chemical applications on Cd, Pb, and As concentrations of wheat-cultivated soils. Consequently, a study area\\u000a was designed and

Zahra Atafar; Alireza Mesdaghinia; Jafar Nouri; Mehdi Homaee; Masoud Yunesian; Mehdi Ahmadimoghaddam; Amir Hossein Mahvi

2010-01-01

372

DNA sequence analysis of bacterial toxic heavy metal resistances  

Microsoft Academic Search

Bacterial plasmids have genes that confer highly specific resistances to As, Bi, Cd, Cu, Cr, Hg, Pb, Te, Zn, and other toxic\\u000a heavy metals. For each toxic cation or anion, generally a different resistance system exists, and these systems may be “linked”\\u000a together on multiple resistance plasmids. For Cd2+, AsO2\\u000a ?, AsO4\\u000a 3?, Hg2+, and organomercurials, DNA sequence analysis has

Simon Silver; Tapan K. Misra; Richard A. Laddaga

1989-01-01

373

Heavy metal soil pollution cartography in northern France  

Microsoft Academic Search

This paper presents maps and analyses of soil contamination by lead and cadmium. Data are for soil samples from the Evin-Malmaison site (Nord Pas-de-Calais, France). The statistical method used to interpolate concentrations of heavy metals enables the drawing of maps and the associated errors. The instrumentation required to follow both the spatial and temporal evolution of these concentrations is discussed.

J.-P. Frangi; D. Richard

1997-01-01

374

Collective Motion of Moshers at Heavy Metal Concerts  

E-print Network

Human collective behavior can vary from calm to panicked depending on social context. Using videos publicly available online, we study the highly energized collective motion of attendees at heavy metal concerts. We find these extreme social gatherings generate similarly extreme behaviors: a disordered gas-like state called a mosh pit and an ordered vortex-like state called a circle pit. Both phenomena are reproduced in flocking simulations demonstrating that human collective behavior is consistent with the predictions of simplified models.

Silverberg, Jesse L; Sethna, James P; Cohen, Itai

2013-01-01

375

Heavy Metals in the Vegetables Collected from Production Sites  

PubMed Central

Background: Contamination of vegetable crops (as an important part of people's diet) with heavy metals is a health concern. Therefore, monitoring levels of heavy metals in vegetables can provide useful information for promoting food safety. The present study was carried out in north-west of Iran (Tabriz) on the content of heavy metals in vegetable crops. Methods: Samples of vegetables including kurrat (n=20) (Allium ampeloprasumssp. Persicum), onion (n=20) (Allium cepa) and tomato (n=18) (Lycopersiconesculentum var. esculentum), were collected from production sites in west of Tabriz and analyzed for presence of Cd, Cr, Cu, Ni, Pb and Zn by atomic absorption spectroscopy (AAS) after extraction by aqua regia method (drying, grounding and acid diges­tion). Results: Mean ± SD (mg/kg DW) concentrations of Cd, Cu, Cr, Ni and Zn were 0.32 ± 0.58, 28.86 ± 28.79, 1.75 ± 2.05, 6.37± 5.61 and 58.01 ± 27.45, respec­tively. Cr, Cu and Zn were present in all the samples and the highest concentra­tions were observed in kurrat (leek). Levels of Cd, Cr and Cu were higher than the acceptable limits. There was significant difference in levels of Cr (P<0.05) and Zn (P<0.001) among the studied vegetables. Positive correlation was observed be­tween Cd:Cu (R=0.659, P<0.001) Cr:Ni (R=0.326, P<0.05) and Cr:Zn (R=0.308, P<0.05).   Conclusion: Level of heavy metals in some of the analyzed vegetables, especially kurrat samples, was higher than the standard levels. Considering the possi­ble health outcomes due to the consumption of contaminated vegetables, it is re­quired to take proper actions for avoiding people's chronic exposure. PMID:24688968

Taghipour, Hassan; Mosaferi, Mohammad

2013-01-01

376

Kinetics and Mechanism of Explosive Decomposition of Heavy Metal Azides  

Microsoft Academic Search

The explosive decomposition of heavy metal azides initiated by a laser pulse was studied experimentally over a broad range\\u000a of action levels (from the threshold values to those exceeding the threshold ignition energy by a factor of 100) and in the\\u000a time interval including the induction period, and rapid explosive decomposition, and the expansion of detonation products.\\u000a The explosive glow

V. I. Korepanov; V. M. Lisitsyn; V. I. Oleshko; V. P. Tsipilev

2006-01-01

377

Electrokinetic Separation of Heavy Metals from Wastewater Treatment Sludge  

Microsoft Academic Search

In the study, a preliminary experiment on the removal of heavy metals from industrial wastewater sludge was carried out to evaluate the feasibility of electrokinetic separation. Four different types of processing fluid—tap water, ethylenediaminetetraacetic acid (EDTA), citric acid (CA), and 0.1 M nitric acid—were tested. EDTA was found to be the most effective agent within the set of chemicals tested for

Seon-Young Park; Geun-Yong Park; Do-Hyung Kim; Jung-Seok Yang; Kitae Baek

2010-01-01

378

Effect of Heavy Metals on Saprotrophic Soil Fungi  

Microsoft Academic Search

Heavy metals represent an important group of soil pollutants that contribute to the formation of specific “toxic” habitats\\u000a characterized by alterations in the relative abundances of soil bacteria and fungi, changes in fungal community composition,\\u000a and interference with environmental processes of soil organic matter transformation. They also contribute to the heterogeneity\\u000a of soil, forming microhabitats that are toxic to varying

Petr Baldrian

379

Effects of Heavy Metals on Soil Enzyme Activities  

Microsoft Academic Search

The pollution of the soil with heavy metals is one of the worst legacies of our intensive agricultural–industrial activities,\\u000a and it negatively affects various characteristics of the soil, including soil enzyme activities. Soil enzymes are natural\\u000a molecules that catalyze soil microbial reactions and mainly originate from microorganisms and plants. Since enzyme activities\\u000a play fundamental roles in soil chemical and biological

Ayten Karaca; Sema Camci Cetin; Oguz Can Turgay; Ridvan Kizilkaya

380

Surfactant biocatalyst for remediation of recalcitrant organics and heavy metals  

DOEpatents

Novel strains of isolated and purified bacteria have been identified which have the ability to degrade petroleum hydrocarbons including a variety of PAHs. Several isolates also exhibit the ability to produce a biosurfactant. The combination of the biosurfactant-producing ability along with the ability to degrade PAHs enhances the efficiency with which PAHs may be degraded. Additionally, the biosurfactant also provides an additional ability to bind heavy metal ions for removal from a soil or aquatic environment.

Brigmon, Robin L. (North Augusta, SC); Story, Sandra (Greenville, SC); Altman, Denis (Evans, GA); Berry, Christopher J. (Aiken, SC)

2009-01-06

381

Surfactant biocatalyst for remediation of recalcitrant organics and heavy metals  

DOEpatents

Novel strains of isolated and purified bacteria have been identified which have the ability to degrade petroleum hydrocarbons including a variety of PAHs. Several isolates also exhibit the ability to produce a biosurfactant. The combination of the biosurfactant-producing ability along with the ability to degrade PAHs enhances the efficiency with which PAHs may be degraded. Additionally, the biosurfactant also provides an additional ability to bind heavy metal ions for removal from a soil or aquatic environment.

Brigmon, Robin L. (North Augusta, SC); Story, Sandra (Greenville, SC); Altman, Denis J. (Evans, GA); Berry, Christopher J. (Aiken, SC)

2011-05-03

382

Surfactant biocatalyst for remediation of recalcitrant organics and heavy metals  

DOEpatents

Novel strains of isolated and purified bacteria have been identified which have the ability to degrade petroleum hydrocarbons including a variety of PAHs. Several isolates also exhibit the ability to produce a biosurfactant. The combination of the biosurfactant-producing ability along with the ability to degrade PAHs enhances the efficiency with which PAHs may be degraded. Additionally, the biosurfactant also provides an additional ability to bind heavy metal ions for removal from a soil or aquatic environment.

Brigmon, Robin L. (North Augusta, SC); Story, Sandra (Greenville, SC); Altman; Denis J. (Evans, GA); Berry, Christopher J. (Aiken, SC)

2011-03-29

383

Surfactant biocatalyst for remediation of recalcitrant organics and heavy metals  

DOEpatents

Novel strains of isolated and purified bacteria have been identified which have the ability to degrade petroleum hydrocarbons including a variety of PAHs. Several isolates also exhibit the ability to produce a biosurfactant. The combination of the biosurfactant-producing ability along with the ability to degrade PAHs enhances the efficiency with which PAHs may be degraded. Additionally, the biosurfactant also provides an additional ability to bind heavy metal ions for removal from a soil or aquatic environment.

Brigmon, Robin L. (North Augusta, SC); Story, Sandra (Greenville, SC); Altman, Denis J. (Evans, GA); Berry, Christopher J. (Aiken, SC)

2011-03-15

384

Heavy Metal Distribution in Some Wild Birds from Korea  

Microsoft Academic Search

This study presents concentrations of heavy metals (manganese, zinc, lead, and cadmium) in tissues in six orders of Korean\\u000a wild birds (n = 37), 2000–2002. Zinc, manganese, lead, and cadmium concentrations in all tissues were highest in ancient murrelets (Synthliboramphus antiquus). Essential elements in Korean wild birds were within the normal range for wild birds and are maintained there by a normal

Jungsoo Kim; Ju-Ryul Shin; Tae-Hoe Koo

2009-01-01

385

Heavy metals leaching in Indian fly ash.  

PubMed

Fly ash is an industrial waste generated from thermal power plants. Fly ash constitutes 80-85% of the total ash produced. A small part of fly ash is utilised in some sectors such as construction materials, building engineering, road, back fill, agriculture, selective engineering and processing useful materials. A large part of fly ash produced is disposed of with very high environmental risk. In the present paper, laboratory leaching test has been used to determine the potential mobility of Pb, Cd, Cr, Cu, Zn, Fe, Mn and Ni in fly ash samples, collected from Chandrapura Thermal Power Plant, Jharkhand and Ramagundam Super Thermal Power Plant, Andhra Pradesh, in order to assess their leachability when these wastes are disposed of. A cascade-leaching test was used at liquid-to-solid ratio (L/S) ranging between 20 and 100. Both fly ash samples exhibited neutral reactions, as indicated by pH values <11.75 and >7.0 at L/S=10 and contact time of 10 minutes. The percentage of leached amounts found to follow the trend Zn>Fe>Mn>Cr>Pb>Cu>Ni>Cd for fly ash from Chandrapura and Fe>Zn>Cu>Mn>Cr>Ni>Pb>Cd for fly ash from Ramagundam. Effect of pH on metals released from ash surface in aqueous solution followed a predictable pattern of decreasing release with increasing pH. PMID:19295096

Prasad, Bably; Mondal, Kajal Kumar

2008-04-01

386

Heavy metal analysis in commercial Spirulina products for human consumption  

PubMed Central

For consumption of health foods of Spirulina, by the general public, health food stores are increasingly offering more exotic products. Though Spirulina consumption is growing worldwide, relatively few studies have reported on the quantities of heavy metals/minerals they contain and/or their potential effects on the population’s health. This study reveals the concentrations of six typical heavy metals/minerals (Ni, Zn, Hg, Pt, Mg, and Mn) in 25 Spirulina products commercialized worldwide for direct human consumption. Samples were ground, digested and quantified by Coupled Plasma Mass Spectroscopy (ICP–MS). The concentrations (mg/kg d.w.) were range from 0.001 to 0.012 (Pt) followed by 0.002–0.028 (Hg), 0.002–0.042 (Mg), 0.005–2.248 (Mn), 0.211–4.672 (Ni) and 0.533–6.225 (Zn). The inorganic elements of the present study were significantly lower than the recommended daily intake (RDI) level of heavy metal elements (mg/daily) Ni (0.4), Zn (13), Hg (0.01), Pt (0.002), Mg (400) and Mn (4). Based on this study the concentration of inorganic elements was not found to exceed the present regulation levels, and they can be considered as safe food. PMID:24235875

Al-Dhabi, Naif Abdullah

2013-01-01

387

Superhydrogels of nanotubes capable of capturing heavy-metal ions.  

PubMed

Self-assembly regulated by hydrogen bonds was successfully achieved in the system of lithocholic acid (LCA) mixed with three organic amines, ethanolamine (EA), diethanolamine (DEA), and triethanolamine (TEA), in aqueous solutions. The mixtures of DEA/LCA exhibit supergelation capability and the hydrogels consist of plenty of network nanotubes with uniform diameters of about 60 nm determined by cryogenic TEM. Interestingly, the sample with the same concentration in a system of EA and LCA is a birefringent solution, in which spherical vesicles and can be transformed into nanotubes as the amount of LCA increases. The formation of hydrogels could be driven by the delicate balance of diverse noncovalent interactions, including electrostatic interactions, hydrophobic interactions, steric effects, van der Waals forces, and mainly hydrogen bonds. The mechanism of self-assembly from spherical bilayer vesicles into nanotubes was proposed. The dried hydrogels with nanotubes were explored to exhibit the excellent capability for capturing heavy-metal ions, for example, Cu(2+), Co(2+), Ni(2+), Pb(2+), and Hg(2+). The superhydrogels of nanotubes from the self-assembly of low-molecular-weight gelators mainly regulated by hydrogen bonds used for the removal of heavy-metal ions is simple, green, and high efficiency, and provide a strategic approach to removing heavy-metal ions from industrial sewage. PMID:24136830

Song, Shasha; Wang, Haiqiao; Song, Aixin; Hao, Jingcheng

2014-01-01

388

Ecological risk assessment of soil pollution with heavy metals  

SciTech Connect

The structure and function of soil ecosystems in an area with a wide range of concentrations of heavy metals were studied in portions of the US Army`s Aberdeen Proving Ground, Maryland. The objective of this project was to develop and test the efficacy of a comprehensive methodology for assessing ecological impacts of soil contamination. A hierarchical approach which integrated biotic parameters and ecosystem processes was used to give insight into the mechanisms that lead to alterations in the structure and function of soil ecosystems in contaminated areas. This approach involved (1) a thorough survey of the soil biota to establish community structure, (2) laboratory and field tests on critical ecosystem processes, (3) toxicity trials, and (4) the use of spatial analyses to provide input in the decision making process. Soil invertebrate communities showed significant reductions in the abundance of several taxonomic and trophic groups in contaminated areas. The numbers of soil microorganisms were lower in areas of soil contamination. Ten-to-fifty fold reductions in enzyme activities were observed as heavy metal concentrations increased. These results suggest that soil contamination with heavy metals may have detrimental effects on soil biota and the rates of organic matter degradation and subsequent release of nutrients to aboveground communities in the area. The proposed methodology appears to offer an efficient and potentially cost saving tool for remedial investigations at contaminated sites.

Kuperman, R.G. [Argonne National Lab., IL (United States)

1995-12-31

389

Heavy metals and pain in the dysfunctional patient  

PubMed Central

Summary Aims The aim of this research is to verify the quality and quantity of heavy metals (HM) of dental origin in TMD patients. Methods A population of 100 subject was studied and divided in two homogeneous groups: Study Group (SG) and Control Group (CG). Organism heavy metals were tested by a spot sampling method in which the first urine of the day, through Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), were analyzed. The results obtained were compared with reference values (RV) of Italian people. Descriptive statistical analysis and student’s t-test has been applied (statistical significance for p > 0.05). Results The SG presented the absolute highest levels of HM compared to the CG (p=0.787). As regards the relation between pain and HM, the subjects that refer “severe/very severe” values of pain present the highest levels of HM in urines. Conclusions The obtained results seem to highlight a possible direct proportionality between the level of pain the increase of the concentration of heavy metals in all the examined groups and subgroups. PMID:25002917

Di Paolo, Carlo; Serritella, Emanuela; Panti, Fabrizio; Falisi, Giovanni; Manna, Fedele

2014-01-01

390

Heavy Metal Contamination in the Taimyr Peninsula, Siberian Arctic  

SciTech Connect

The Taimyr Peninsula is directly north of the world's largest heavy metal smelting complex (Norilsk, Russia). Despite this proximity, there has been little research to examine the extent of contamination of the Taimyr Peninsula. We analyzed heavy metal concentrations in lichen (Cetraria cucullata), moss (Hylocomium splendens), soils, lake sediment, freshwater fish (Salvelinus alpinus, Lota lota, and Coregonus spp.) and collared lemming (Dicrostonyx torquatus) from 13 sites between 30 and 300 km from Norilsk. Element concentrations were low in both C. cucullata and H. splendens, although concentrations of Al, Fe, Cu, Ni, and Pb were significantly higher than those in Arctic Alaska, probably due to natural differences in the geochemical environments. Inorganic surface soils had significantly higher concentrations of Cd, Zn, Pb, and Mg than inorganic soils at depth, although a lake sediment core from the eastern Taimyr Peninsula indicated no recent enrichment by atmospherically transported elements. Tissue concentrations of heavy metals in fish and lemming were not elevated relative to other Arctic sites. Our results show that the impact of the Norilsk smelting complex is primarily localized rather than regional, and does not extend northward beyond 100 km.

Allen-Gil, Susan M.; Ford, Jesse; Lasorsa, Brenda K.; Monetti, Matthew; Vlasova, Tamara; Landers, Dixon H.

2003-01-01

391

Water Purification Using Functional Nanomaterials: Sequestering Toxic Heavy Metals  

SciTech Connect

Water, and water quality, are issues of critical importance to the future of humankind. Our water supply has been contaminated by a wide variety of industrial, military and natural sources. There is a serious need for technologies to remove toxic heavy metals and radionuclides from the world’s water supplies. Surfactant templated synthesis of mesoporous ceramics provides a versatile foundation upon which to create high efficiency environmental sorbents. These nanoporous ceramics condense a huge amount of surface area into a very small volume. These mesoporous architectures can be subsequently functionalized through molecular self-assembly. These functional mesoporous materials offer significant capabilities in terms of removal of heavy metals and radionuclides from groundwater and other liquid media. They are highly efficient sorbents, whose interfacial chemistry can be fine-tuned to selectively sequester a specific target species, such as heavy metals, tetrahedral oxometallate anions and radionuclides. Their rigid, open pore structure allows for rapid, efficient sorption kinetics. This manuscript provides an overview of the design, synthesis and performance of the sorbent materials.

Fryxell, Glen E.

2008-02-01

392

Heavy metals in commercial fish in New Jersey  

SciTech Connect

Levels of contaminants in fish are of particular interest because of the potential risk to humans who consume them. While attention has focused on self-caught fish, most of the fish eaten by the American public comes from commercial sources. We sampled 11 types of fish and shellfish obtained from supermarkets and specialty fish markets in New Jersey and analyzed them for arsenic, cadmium, chromium, lead, manganese, mercury, and selenium. We test the null hypothesis that metal levels do not vary among fish types, and we consider whether the levels of any metals could harm the fish themselves or their predators or pose a health risk for human consumers. There were significant interspecific differences for all metals, and no fish types had the highest levels of more than two metals. There were few significant correlations (Kendall tau) among metals for the three most numerous fish (yellowfin tuna, bluefish, and flounder), the correlations were generally low (below 0.40), and many correlations were negative. Only manganese and lead positively were correlated for tuna, bluefish, and flounder. The levels of most metals were below those known to cause adverse effects in the fish themselves. However, the levels of arsenic, lead, mercury, and selenium in some fish were in the range known to cause some sublethal effects in sensitive predatory birds and mammals and in some fish exceeded health-based standards. The greatest risk from different metals resided in different fish; the species of fish with the highest levels of a given metal sometimes exceeded the human health guidance or standards for that metal. Thus, the risk information given to the public (mainly about mercury) does not present a complete picture. The potential of harm from other metals suggests that people not only should eat smaller quantities of fish known to accumulate mercury but also should eat a diversity of fish to avoid consuming unhealthy quantities of other heavy metals. However, consumers should bear in mind that standards have a margin of safety.

Burger, Joanna [Division of Life Sciences, 604 Allison Road, Piscataway, NJ 08854-8082 (United States) and Environmental and Occupational Health Sciences Institute and Consortium for Risk Evaluation with Stakeholder Participation, Piscataway, NJ 08854 (United States)]. E-mail: burger@biology.rutgers.edu; Gochfeld, Michael [Environmental and Occupational Health Sciences Institute and Consortium for Risk Evaluation with Stakeholder Participation, Piscataway, NJ 08854 (United States); Environmental and Occupational Medicine, UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ 08854 (United States)

2005-11-15

393

Chitosan removes toxic heavy metal ions from cigarette mainstream smoke  

NASA Astrophysics Data System (ADS)

This study investigated the removal of heavy metal ions from cigarette mainstream smoke using chitosan. Chitosan of various deacetylation degrees and molecular weights were manually added to cigarette filters in different dosages. The mainstream smoke particulate matter was collected by a Cambridge filter pad, digested by a microwave digestor, and then analyzed for contents of heavy metal ions, including As(III/V), Pb(II), Cd(II), Cr(III/VI) and Ni(II), by graphite furnace atomic absorption spectrometry (GFAAS). The results showed that chitosan had a removal effect on Pb(II), Cd(II), Cr(III/VI) and Ni(II). Of these, the percent removal of Ni(II) was elevated with an increasing dosage of chitosan. Chitosan of a high deace tylation degree exhibited good binding performance toward Cd(II), Cr(III/VI) and Ni(II), though with poor efficiency for Pb(II). Except As(III/V), all the tested metal ions showed similar tendencies in the growing contents with an increasing chitosan molecular weight. Nonetheless, the percent removal of Cr(III/VI) peaked with a chitosan molecular weight of 200 kDa, followed by a dramatic decrease with an increasing chitosan molecular weight. Generally, chitosan had different removal effects on four out of five tested metal ions, and the percent removal of Cd(II), Pb(II), Cr(III/VI) and Ni(II) was approximately 55%, 45%, 50%, and 16%, respectively. In a word, chitosan used in cigarette filter can remove toxic heavy metal ions in the mainstream smoke, improve cigarette safety, and reduce the harm to smokers.

Zhou, Wen; Xu, Ying; Wang, Dongfeng; Zhou, Shilu

2013-09-01

394

Bioaccumulation of heavy metals in macroinvertebrates living in stormwater wetlands  

SciTech Connect

The design of stormwater wetlands and ponds as wildlife habitats has prompted concern over the potential uptake of runoff contaminants by aquatic fauna. Stormwater wetlands provide a diverse array of habitat for aquatic macroinvertebrates. The importance of macroinvertebrates in aquatic communities has been well documented. Aquatic macroinvertebrates also serve as a major food source of many aquatic vertebrates, including fish and birds. The objectives of the study were to: (1) examine the responses of the macroinvertebrate community to water and sediment concentrations of heavy metals, and other water quality parameters; (2) determine whether macroinvertebrates living in stormwater wetlands bioaccumulate significant concentrations of heavy metals; (3) relate the concentrations of heavy metals in sediment, water and macroinvertebrates to land use in the surrounding watershed; (4) determine sediment and water toxicity to macroinvertebrates. Twenty stormwater wetlands, representing four land uses commercial, residential, highway and control, were monitored in this study. Water quality parameters, including pH, DO, turbidity, conductivity, hardness and metal concentrations were monitored bi-weekly for six months. Sediment samples were collected three times during the same period. Macroinvertebrate communities were sampled during alternate weeks after water collections. Ten-day sediment bioassays were conducted using the amphipod Hyalella azteca. Preliminary data analyses have indicated no significant difference in sediment and water metal concentrations between land uses. However, Zn concentrations in macroinvertebrates were significantly higher (p < 0.05) in wetlands serving commercial watersheds than in those serving the remaining three land uses. No differences have been detected in composition of invertebrate communities due to land use category.

Karouna, N.K.; Sparling, D.W. [National Biological Service, Laurel, MD (United States)

1995-12-31

395

Heavy metal tolerance and accumulation in metallicolous and non-metallicolous populations of Thlaspi caerulescens from continental Europe  

Microsoft Academic Search

In continental Europe, the heavy metal hyperaccumulator Thlaspi caerulescens occurs both on heavy-metal polluted soils (subsp. calaminare) and on soils with normal heavy metal content (subsp. caerulescens). In order to assess the extent and partitioning of variation in heavy metal tolerance and foliar mineral composition, twelve families from two populations of each subspecies were grown in pots in four soil

Pierre Meerts; Nathalie Van Isacker

1997-01-01

396

1. Coastal waters are often exposed to heavy metals (HM) introduced from point and diffusive sources. Chronic and  

E-print Network

1. Coastal waters are often exposed to heavy metals (HM) introduced from point and diffusive and ALF3-ALF6. Sampling during 04/2004 5. Heavy metals concentration in Amphistegina lobifera is far higher than in sea water. Heavy metals concentration in seawater 4. Most of the dissolved heavy metals

Einat, Aharonov

397

Heavy metals in sludge from the sewage treatment plant of Rio de Janeiro  

Microsoft Academic Search

The final disposal of sewage sludge on soils as a compost for agriculture increases heavy metal contamination in soils. This demands controlled use to avoid hazardous situations. This work measures the heavy metals content in sludge and its potential as a fertilizer in agriculture. Samples were collected from the Penha urban sewage plant, the largest in Rio de Janeiro. Heavy

Tomaz Langenbach; Wolfgang Pfeifer; Luiz Rodrigues Freire; Michele Sarpa; Sueli Paim

1994-01-01

398

Climate change impacts on the leaching of a heavy metal contamination in a small lowland catchment  

E-print Network

Climate change impacts on the leaching of a heavy metal contamination in a small lowland catchment was to assess the effects of future projected climate change on the hydrology and the leaching of heavy metals. As a result, lower concentrations of Cd and Zn in surface water are projected. The reduced leaching of heavy

Fowler, Hayley

399

Effects of Heavy Metal Pollution on Oak Leaf Microorganisms  

PubMed Central

During the growing season, comparisons were made of the leaf surface microflora of (i) two groups of mature oak trees, one in the vicinity of a smelting complex contaminated by heavy metals and the other at a relatively uncontaminated site, and (ii) two groups of oak saplings at the uncontaminated site, one of which was sprayed with zinc, lead, and cadmium to simulate the heavy metal pollution from the smelter without the complicating effects of other pollutants. Total viable counts of bacteria, yeasts, and filamentous fungi (isolated by leaf washing) were generally little affected by the spraying treatment, whereas polluted leaves of mature trees supported fewer bacteria compared with leaves of mature trees at the uncontaminated site. Numbers of pigmented yeasts were lower on polluted oaks and on metal-dosed saplings compared with their respective controls. Polluted leaves of mature trees supported both greater numbers of Aureobasidium pullulans and Cladosporium spp. and a greater percentage of metal-tolerant fungi compared with oak leaves at the uncontaminated site. There were no significant overall differences in the degree of mycelial growth between the two groups of saplings or the mature trees. PMID:16345669

Bewley, Richard J. F.

1980-01-01

400

Leaching of heavy metals in acid mine drainage.  

PubMed

Acid mine drainage is one of the most serious environmental problems that the coal and metal mining industry is currently facing. The generation of low pH drainage enhances the dissolution of heavy metals in water. The samples used in this research originated from three pits at mine dumps. In a study reported in this paper, three types of tests; namely static test, kinetic test and column test were conducted to estimate acid generation and acid neutralization reaction rates, and to predict the solubility of metals and their release rates. Static test showed that all samples had a pH of net acid generation (NAG pH) <4, a net acid producing potential (NAPP) >10 kg H2SO4tonne(-1), and a S-content >3%, which can be classified as a high acid-forming capacity. Simulated runoff in the column tests was equivalent to 5-year average rainfall in Indonesia, the resultant leachates showed acidic behaviour (pH < 3.5). Based on the results, it was found that high mobilization of heavy metals (Cr, Cu, Zn, Cd and Pb) takes place under strong acidic conditions (pH approximately equal 2). PMID:16634228

Saria, Lana; Shimaoka, Takayuki; Miyawaki, Kentaro

2006-04-01

401

Improving the sensitivity of bacterial bioreporters for heavy metals  

PubMed Central

Whole-cell bacterial bioreporters represent a convenient testing method for quantifying the bioavailability of contaminants in environmental samples. Despite the fact that several bioreporters have been constructed for measuring heavy metals, their application to environmental samples has remained minimal. The major drawbacks of the available bioreporters include a lack of sensitivity and specificity. Here, we report an improvement in the limit of detection of bacterial bioreporters by interfering with the natural metal homeostasis system of the host bacterium. The limit of detection of a Pseudomonas putida KT2440-based Zn/Cd/Pb-biosensor was improved by a factor of up to 45 by disrupting four main efflux transporters for Zn/Cd/Pb and thereby causing the metals to accumulate in the cell. The specificity of the bioreporter could be modified by changing the sensor element. A Zn-specific bioreporter was achieved by using the promoter of the cadA1 gene from P. putida as a sensor element. The constructed transporter-deficient P. putida reporter strain detected Zn2+ concentrations about 50 times lower than that possible with other available Zn-bioreporters. The achieved detection limits were significantly below the permitted limit values for Zn and Pb in water and in soil, allowing for reliable detection of heavy metals in the environment. PMID:21326938

Tönismann, Karmen; Virta, Marko

2010-01-01

402

Heavy metals and neurodegenerative diseases: an observational study.  

PubMed

In this study, we evaluated the levels of some of the most investigated metals (Cu, Se, Zn, Pb, and Hg) in the blood of patients affected by the most common chronic neurodegenerative diseases like Alzheimer's disease (AD) and multiple sclerosis (MS), in order to better clarify their involvement. For the first time, we investigated a Sicilian population living in an area exposed to a potentially contaminated environment from dust and fumes of volcano Etna and consumer of a considerable quantity of fish in their diet, so that this represents a good cohort to demonstrate a possible link between metals levels and development of neurodegenerative disorders. More specifically, 15 patients affected by AD, 41 patients affected by MS, 23 healthy controls, and 10 healthy elderly controls were recruited and subjected to a venous blood sampling. Quantification of heavy metals was performed by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). This technique has allowed us to establish that there is a concomitance of heavy metal unbalance associated with AD more than in other neurodegenerative pathologies, such as MS. Also, we can assess that the concentration of these elements is independent from the diet, especially from occasional or habitual consumption of fruits and vegetables, prevalence in the diet of meat or fish, possible exposure to contaminated environment due both to the occupation and place of residence. PMID:25107328

Giacoppo, Sabrina; Galuppo, Maria; Calabrò, Rocco Salvatore; D'Aleo, Giangaetano; Marra, Angela; Sessa, Edoardo; Bua, Daniel Giuseppe; Potortì, Angela Giorgia; Dugo, Giacomo; Bramanti, Placido; Mazzon, Emanuela

2014-11-01

403

Accumulation of heavy metals in the mole in Finland.  

PubMed

Metal concentrations (Cu, Ni, Zn, Cd, Cr, Hg, Pb and Mo) were analysed from the liver and kidneys of moles, Talpa europaea L. (Insectivora), trapped in southern Finland on both contaminated and rural areas. In rural areas the concentrations of Cd, Cu, Zn, Pb and Mo were lower in juveniles (individuals in their first summer), except for Zn in the liver, which was lower in adults. When the animals were divided into annual classes (0-6 years), Cd and Mo concentrations in the liver increased significantly with age, while concentrations of Cu, Zn and Cr tended to decrease. Female moles had higher Pb concentrations than males, especially adult females, which also had lower levels of Cu in the liver than adult males. Moles in the metropolitan area of Helsinki clearly differed from those in rural areas in that the concentrations of heavy metals in these moles were higher (especially for the most toxic metals: Cd, Pb and Hg), and their body weight was lower. The renal concentrations of Cd in most of the moles in Helsinki exceeded the threshold that has been shown to have a nephrotoxic effect in mammals. In one subsample from Helsinki, Pb and Zn concentrations in the mole liver decreased as the distance from the highway increased. Concentrations of Pb in earthworms and several heavy metals in soil also decreased similarly in the same area. Our data indicate that Pb accumulates in moles through their diet of earthworms. PMID:15091866

Pankakoski, E; Hyvärinen, H; Jalkanen, M; Koivisto, I

1993-01-01

404

Broom fibre PRB for heavy metals groundwater remediation  

NASA Astrophysics Data System (ADS)

Soil contamination by heavy metal and, though it, of groundwater represent a serious alteration of original geochemical levels owing to various human activities as: particular industrial processes and their non-correct treatment emission, urban traffic, use of phytosanitary product and mineral fertilizer. Heavy metals are genotoxic contaminants who can be found by environmental matrix analysis or by examination of the genetic damage inducted, after exposition, to sentry organism. In this last case we use a relative quantitation of the gene expression monitoring the mitochondrial oxidative metabolism hepatopancreas's gene of the organism used by bioindicator. This test is based on consideration that the hepatopancreas is the first internal organ affected by heavy metals or any other pollutant that the organism is exposed. In this work, the organism used by bioindicator to evalutate the pollutant contamination of waste water is Danio rerio (Zebrafish) that is a little tropical fish of 2-3 cm, native on asiatic south-east rivers. This organism has a large use in scientific field because its genoma is almost completely mapped and, above all, because the congenital gene cause in human, if it was mutated in zebrafish, similar damage or almost similar mutation that happens in human being so you can develop a dose - response curve. To do this, after prepared a cadmium solution with a concentration 10 times the Italian normative limit, the organisms have been put in the aquarium to recreate the optimal condition to survival of zebrafish observed by continuous monitoring by web-cam. After one month exposition, that we took little by little sample fish to analyzing, for different exposition time, the hepatopancreas's fish. First results shows considerable variation of the gene expression by interested gene in mitochondrial oxidative metabolism compared to control, highlighting the mutagenity caused by heavy metals on Danio rerio's hepatopancreas and, mutatis mutandis, also in human being. One of the most interesting techniques applied in contaminated aquifer by heavy metals is the PRBs (Troisi et al., 2002; Calvin et al., 2006), in particular broom fibers PRB (Troisi et al., 2008). The first results highlight an optimum removal capacity for contaminants underlined from following removal percentage: 98.01% (Cd), 99.95% (Cu), 97.35% (Pb) and 99.53% (Zn). A fundamental parameter for PRB design is the decay coefficient who indicates the removal capacity (degradation, transformation, adsorption/absorption, mass transport, etc.). This parameter has been determined for four heavy metals: Cadmium (Cd), Copper (Cu), Lead (Pb) and Zinc (Zn) carrying out column tests. Besides, for real use of broom fibers PRB same tests have been performed, using flow cells, to estimate a relation between hydraulic conductivity of fiber and its density. References Chien C. C., H. I. Inyang and L.G. Everett (2006). Barrier Systems for Environmental Contaminant Containment and Treatment. Taylor and Francis Group eds. Troisi S., C. Fallico, S. Straface S. e L. Mazzuca. (2008). Biodreni per la bonifica di siti contaminati realizzati con fibre naturali liberiane ad elevato sviluppo superficiale. CS2008A00018. Università della Calabria. Troisi S, E. Migliari and S. Straface (2002). Soil and groundwater contamination by heavy metals in the industrial area of Crotone. Third International Conference Risk Analysis III. Sintra, Ed. by C.A. Brebbia. WIT Press.

Molinari, A.; Troisi, S.; Fallico, C.; Paparella, A.; Straface, S.

2009-04-01

405

Flue-gas-influenced heavy metal bioaccumulation by the indigenous microalgae Desmodesmus communis LUCC 002.  

PubMed

Desmodesmus communis LUCC 002 was cultivated using flue gas originating from a coal-fired power plant as a carbon dioxide (CO2) source. The flue gas contains various heavy metals. For investigating the fate of flue-gas-introduced metals on the cultivation system, bioaccumulation was measured in the microalgal biomass and milieu. The accumulated biomass was found to contain eight heavy metals: arsenic, chromium, barium, lead, selenium, silver, cadmium, and mercury. High heavy metal accumulations were also found in the control group of algae grown without the addition of flue gas at the same location. Further testing revealed that some of the heavy metals originated from well water used in the cultivation. The flue-gas-influenced bioaccumulation pattern of different heavy metals was observed. The responses of individual heavy metals and the influence of well water microbial flora on the algal growth were investigated, this study showed that hormesis was developed by the D. communis LUCC 002. PMID:25184415

Palanisami, Swaminathan; Lee, Keesoo; Balakrishnan, Baskar; Nam, Paul Ki-Souk

2015-02-01

406

Kinetics of heavy metal inhibition of 1,2-dichloroethane biodegradation in co-contaminated water.  

PubMed

Sites co-contaminated with heavy metals and 1,2-DCA may pose a greater challenge for bioremediation, as the heavy metals could inhibit the activities of microbes involved in biodegradation. Therefore, this study was undertaken to quantitatively assess the effects of heavy metals (arsenic, cadmium, mercury, and lead) on 1,2-DCA biodegradation in co-contaminated water. The minimum inhibitory concentrations (MICs) and concentrations of the heavy metals that caused half-life doubling (HLDs) of 1,2-DCA as well as the degradation rate coefficient (k1 ) and half-life (t½ ) of 1,2-DCA were measured and used to predict the toxicity of the heavy metals in the water microcosms. An increase in heavy metal concentration resulted in a progressive increase in the t½ and relative t½ and a decrease in k1 . The MICs and HLDs of the heavy metals were found to vary, depending on the heavy metals type. In addition, the presence of heavy metals was shown to inhibit 1,2-DCA biodegradation in a dose-dependent manner, with the following order of decreasing inhibitory effect: Hg(2+) ?>?As(3+) ?>?Cd(2+) ?>?Pb(2+) . Findings from this study have significant implications for the development of bioremediation strategies for effective degradation of 1,2-DCA and other related compounds in wastewater co-contaminated with heavy metals. PMID:23687001

Arjoon, Ashmita; Olaniran, Ademola Olufolahan; Pillay, Balakrishna

2015-03-01

407

Water-soluble organophosphorus reagents for mineralization of heavy metals.  

SciTech Connect

In this report, we have described the principal stages of a two-step process for the in-situ stabilization of actinide ions in the environment. The combination of cation exchange and mineralization appears likely to provide a long-term solution to environments contaminated with heavy metals. Relying on a naturally occurring sequestering agent has obvious potential advantages from a regulatory standpoint. There are additional aspects of this technology requiring further elucidation, including the demonstration of the effect of these treatment protocols on the geohydrology of soil columns, further examination of the influence of humates and other colloidal species on cation uptake, and microbiological studies of phytate hydrolysis. We have learned during the course of this investigation that phytic acid is potentially available in large quantities. In the US alone, phytic acid is produced at an annual rate of several hundred thousand metric tons as a byproduct of fermentation processes (11). This material presently is not isolated for use. Instead, most of the insoluble phyate (as phytin) is being recycled along with the other solid fermentation residues for animal feed. This material is in fact considered undesirable in animal feed. The details of possible separation processes for phytate from these residues would have to be worked out before this untapped resource would be available for application to heavy metal sequestration. The results described emphasize the behavior of actinide and trivalent lanthanide metal ions, as these species are of primary interest to the Department of Energy for the cleanup of the former nuclear weapons production complex. While the specific demonstration includes this limited selection of metal ions, the technique should be readily applicable to any class of metal ions that form insoluble phosphate compounds under appropriate conditions. Further, though this demonstration has been conducted in the pH 5-8 range, it is conceivable that the basic concepts would apply equally well for the stabilization of waste metals in mill tailings piles, wherein conditions can be moderately acidic.

Nash, K. L.

1999-02-26

408

Heavy metal concentrations in edible barnacles exposed to natural contamination.  

PubMed

The giant barnacle Megabalanus azoricus is a popular seafood in the Azores. It is mainly caught in coastal environments and sold for domestic human consumption. This species is a filter feeder and can be used as a biomonitor of trace metal bioavailabilities. To investigate consumption safety, the concentrations of 10 trace metals - As, Cd, Cr, Cu, Mn, Pb, Rb, Se, Sr and Zn - were evaluated in 3 body tissues of M. azoricus from 3 sites on 2 islands. There were no significant differences between the metal loads of the barnacles from the different sites. However, the concentrations of the total trace metal loads revealed significant differences among the tissues (cirrus, muscles and ovaries). The concentrations of some metals in the body were not within the safety levels for consumers, based on the allowable standard levels for crustaceans issued by the European Union and of legislations in several countries. Alarming levels of As and Cd were found. Considering the absence of heavy industry in the region, a non-anthropogenic volcanic source was assumed to be the reason for the observed metal levels. Barnacles, in particular M. azoricus, seem to be useful as bioindicators in this peculiar environment. PMID:23380032

Dionísio, M; Costa, A; Rodrigues, A

2013-04-01

409

Factorial experimental design for recovering heavy metals from sludge with ion-exchange resin.  

PubMed

Wastewaters containing heavy metals are usually treated by chemical precipitation method in Taiwan. This method can remove heavy metals form wastewaters efficiently, but the resultant heavy metal sludge is classified as hazardous solid waste and becomes another environmental problem. If we can remove heavy metals from sludge, it becomes non-hazardous waste and the treatment cost can be greatly reduced. This study aims at using ion-exchange resin to remove heavy metals such as copper, zinc, cadmium, and chromium from sludge generated by a PCB manufacturing plant. Factorial experimental design methodology was used to study the heavy metal removal efficiency. The total metal concentrations in the sludge, resin, and solution phases were measured respectively after 30 min reaction with varying leaching agents (citric acid and nitric acid); ion-exchange resins (Amberlite IRC-718 and IR-120), and temperatures (50 and 70 degrees C). The experimental results and statistical analysis show that a stronger leaching acid and a higher temperature both favor lower heavy metal residues in the sludge. Two-factors and even three-factor interaction effects on the heavy metal sorption in the resin phase are not negligible. The ion-exchange resin plays an important role in the sludge extraction or metal recovery. Empirical regression models were also obtained and used to predict the heavy metal profiles with satisfactory results. PMID:16843592

Lee, I Hsien; Kuan, Yu-Chung; Chern, Jia-Ming

2006-12-01

410

The effects of fire temperatures on water soluble heavy metals.  

NASA Astrophysics Data System (ADS)

Fire ash are majority composed by base cations, however the mineralized organic matter, led also available to transport a higher quantity of heavy metals that potentially could increase a toxicity in soil and water resources. The amount availability of these elements depend on the environment were the fire took place, burning temperature and combusted tree specie. The soil and water contamination from fire ash has been neglected, because the majority of studies are focused on base cations dynamic. Our research, beside contemplate major elements, is focused in to study the behavior of heavy metals released from ash slurries created at several temperatures under laboratory environment, prescribed fires and wildland fires. The results presented in these communication are preliminary and study the presence of Aluminium (Al3+), Manganese (Mn2+), Iron (Fe2+) and Zinc (Zn2+) of ash slurries generated in laboratory environment at several temperatures (150°, 200°, 250°, 300°, 350°, 400°,450°, 500°, 550°C) from Quercus suber, Quercus robur, Pinus pinea and Pinus pinaster and from a low medium temperature prescribed fire in a forest dominated Quercus suber trees. We observed that ash produced at lower and medium temperatures (<300-400°C) released in water higher contents of Al3+ than unburned sample, especially in Quercus species and Mn2+ in Pinus ashes. Fe2+ and Zn2+ showed a reduced concentration in test solution in relation to unburned sample at all temperatures of exposition. In the results obtained from prescribed fire, we identify a higher release of Al3+ and a decrease of the remain elements. The solubilization of these elements are related with pH levels and ash calcite content, because their ability to capture ions in solution. Moreover, the amount and the type of ions released in relation to unburned sample vary in each specie. In this study Al3+ release is related with Quercus species and Mn2+ with Pinus species. Fire ashes can be an environmental problem, because at long term can increase soil acidity. After all base cations have being leached, pH values decrease, and the heavy metals remaining in the ash are easily transported with unknown impacts on soil and water resources. Research is needed in the study at long term of the effects of fire in metals accumulation in soil resources, and all these aspects will be discussed. Keywords: Fire ash, heavy metals, Quercus suber, Quercus robur, Pinus pinea, Pinus pinaster, prescribed fire, pH, Calcite

Pereira, P.; Ubeda, X.; Martin, D. A.

2009-04-01

411

Heavy metal toxicity: Effect on plant growth, biochemical parameters and metal accumulation by Brassica juncea L  

Microsoft Academic Search

Plant growth, pigment concentration, biochemical parameters and uptake of heavy metals were determined for Brassica juncea L. in response to cadmium and lead stress. The plant exhibited a decline in growth, chlorophyll content and carotenoids with Cd and Pb but Cd was found to be more detrimental than Pb treatment in B. juncea. The protein content was decreased by Cd

R. John; P. Ahmad; K. Gadgil; S. Sharma

412

Fungal biosorption – an alternative to meet the challenges of heavy metal pollution in aqueous solutions  

Microsoft Academic Search

The removal of heavy metal from the environment, especially wastewater, is now shifting from the use of conventional methods to the use of biosorption, which may be defined as the binding and concentration of selected heavy metal ions or other molecules on to certain biological material. Although most biosorption research concerns metal and related pollutants, including radionuclides, the term is

Rajesh Dhankhar; Anju Hooda

2011-01-01

413

Water Research 37 (2003) 43114330 A review of the biochemistry of heavy metal  

E-print Network

Water Research 37 (2003) 4311­4330 Review A review of the biochemistry of heavy metal biosorption, termed biosorption, requires that the substrate displays high metal uptake and selectivity, as well Biosorption is a term that describes the removal of heavy metals by the passive binding to non-living biomass

Long, Bernard

2003-01-01

414

EFFECTS OF HIGH TEMPERATURE MELTING ON FRACTIONATION OF HEAVY METALS IN SEWAGE SLUDGE  

Microsoft Academic Search

Sewage sludge from aerobic treatment plant was found to contain high amounts of heavy metals. Research was carried out to investigate the speciation and leaching behavior of heavy metals when using high temperature melting technology for treatment. This was achieved by conducting a sequential chemical extraction procedure and EP-TOX leaching test. The thermal treatment led to increased shift of metals

Azni Idris; Katayon Saed

2002-01-01

415

Mosses as bioindicators of heavy metal pollution in polish national parks  

Microsoft Academic Search

The concentrations of heavy metals (Cd, Co, Cr, Ni, Cu, Ph, Zn, Mn, Fe) and other elements (Mg, Na, K, Ca) were determined in the samples of Pleurozium schreberi and Hylocomium splendens from 12 Polish national parks. The significant differences in the concentrations of all heavy metals between particular parks were found. The lowest concentrations of these metals were recorded

Krystyna Grodzi?vska

1978-01-01

416

Fungal biosorption — an alternative treatment option for heavy metal bearing wastewaters: a review  

Microsoft Academic Search

The common filamentous fungi can sorb heavy metals from aqueous solutions. The sorption of heavy metals, Cu, Zn, Cd, Pb, Fe, Ni, Ag, Th, Ra and U, by fungal biomass has been observed to varying extents. Fungal biosorption largely depends on parameters such as pH, metal ion and biomass concentration, physical or chemical pre-treatment of biomass, presence of various ligands

A. Kapoor; T. Viraraghavan

1995-01-01

417

Biosorptton of heavy metal cations by non?viable yeast biomass  

Microsoft Academic Search

Granular biosorbent biomass was produced by treating yeast with hot alkali. The granular biomass was capable of accumulating a wide range of heavy metal cations (Fe, Cu, Cr, Hg, Pb, Cd, Co, Ag, Ni, and Fe) but not an anion (Cr2O7 ) or an alkaline?earth metal (Ca). Accumulation within the heavy metal group was selective (Cu > Cr > Cd

D. Brady; A. Stoll; J. R. Duncan

1994-01-01

418

THE SOURCES AND BEHAVIOR OF HEAVY METALS IN WASTEWATER AND SLUDGES  

EPA Science Inventory

A critical evaluation has been made of the literature regarding the sources of heavy metals in sludges from municipal wastewater treatment plants. Residential loadings of heavy metals as a percentage of total metal loads are highly variable with respect to both the particular ele...

419

Biomarkers of Renal Effects in Children and Adults with Low Environmental Exposure to Heavy Metals  

Microsoft Academic Search

The health effects of chronic exposure to heavy metals such as lead, cadmium, and mercury are widely documented, yet few data exist about the renal impact of low environmental exposure to these metals, particularly in children. The aim of this study was to assess renal parameters in children and adults living in an environment known for its past heavy metal

Claire de Burbure; Jean-Pierre Buchet; Alfred Bernard; Ariane Leroyer; Catherine Nisse; Jean-Marie Haguenoer; Enrico Bergamaschi; Antonio Mutti

2003-01-01

420

Spatial and temporal trends in heavy metal concentrations in mussels from Northern Ireland coastal waters  

Microsoft Academic Search

Data are presented on the heavy metal concentrations in mussels, Mytilus edulis (L), sampled over a 1 yr period (August 1980–August 1981) from Northern Ireland coastal waters. The study was aimed at investigating the spatial extent and temporal trends in heavy metal contamination and highlighting any areas with exceptionally high levels of toxic metals. With the exception of two sites

N. F. S. Gault; E. L. C. Tolland; J. G. Parker

1983-01-01

421

Assessment of heavy metal contamination and its mobilization from municipal solid waste open dumping site  

Microsoft Academic Search

Influence of heavy metals was investigated by conducting various tests on the samples collected from Nonthaburi dumpsite in Thailand. The heavy metal concentration in the solid waste and its mobility potential based on its binding forms was studied. The sequential extraction method was used to determine the binding forms of metals.From the analysis, Zn was found to be highest concentrated

Tawach Prechthai; Preeda Parkpian; Chettiyappan Visvanathan

2008-01-01

422

BIOAVAILABILITY AND SAFETY ISSUES OF HEAVY METALS IN PADDY SOIL-RICE CONTINUUM IN KOREA  

Microsoft Academic Search

There is an increasing concern over heavy metal contamination of agricultural soils and the successive translocation of metals to rice in Korea. Rice is one of the most important crops in the country. Thus, it is very important to monitor the status and trend of heavy metal contamination in paddy soils and rice periodically. It is also important to verify

Won-Il Kim; Jae E. Yang; Goo-Bok Jung; Byung-Jun Park; Sang-Won Park; Jin-Kyoung Kim; Oh-Kyung Kwon; Gab-Hee Ryu

423

Heavy Metal Contaminated Sediments of Lower Passaic River, New Jersey USA Victor Onwueme1  

E-print Network

Heavy Metal Contaminated Sediments of Lower Passaic River, New Jersey USA Victor Onwueme1 , Huan benchmarks and probable ecological stressors. Heavy metals remains chemicals of concern in the Passaic River and Geographic Information Systems (GIS) to study the spatial distributions of metals ( Ag, Cr,Hg, Pb, and Zn

Brookhaven National Laboratory

424

Heavy metals in urban soils of the Granada city (Spain)  

NASA Astrophysics Data System (ADS)

Urban soils (Anthrosols, Technosols, and the remaining natural patches) are essential components of the city ecosystems influencing the quality of life for people. Unfortunately, because of the high concentration of matter and energy that occurs in any city, these soils might accumulate potentially toxic pollutants such as heavy metals, organic compounds, pathogens, pharmaceuticals, and soluble salts. Contamination by heavy metals has been considered especially dangerous because they can affect human health via inhalation of dust, ingestion, or skin contact with soils. Children are the more exposed citizens in gardens and parks. Accordingly, our objective was to analyze the content of heavy metals in soils of the two most emblematic, extensive, and visited landscaped areas of the Granada city (Salón Garden, which dates back to 1612, and Federico García Lorca Park, opened since 1993) for assessing the health hazard. Using a composite sampling of 20-30 points chosen at random, we collected the upper soil (10 cm) of five representative plots for each landscaped area. We determined soil characteristics by routine procedures and metal elements using ICP-mass. From high to low concentration we found Mn, Ba, Pb, Zn, V, Sn, Cr, Cu, Ni, Sb, Y, As, Sc, Co, Th, Au, U, Mo, Be, Bi, Tl, Cd, and In; the first 10 metals ranging between 478 and 22 ppm. Mn, Ba, and other trace elements were strongly correlated with soil properties suggesting the inheritance as a possible source of metal variation, especially in the soils of younger Park, where the materials used to build gardens in the five sampled plots seemed to be more variable (carbonates: 10-40%, clay: 18-26%, pH: 7.6-7.9, organic matter: 3-7%, free iron 0.5-1.1%). The content of many other metals measured in the sampled plots, however, were independent of soil material and management. On the other hand, compared to agricultural and native soils of the surroundings, our urban soils had obviously greater content in organic matter and nutrients as a result of the garden management, but was unexpected the abundance of heavy metals of urban provenance. Especially the concentration in Pb (83-322 ppm) and Cu (37-48 ppm), common in the city fumes, was higher in the urban soils. Considering the total content of metals, the soils of Salón Gardens also had 200 ppm (45% in Pb) more than those of Federico García Lorca Park, with statistically significant differences (P<0.05) in Zn, Cd, and Pb, which could be explained by a longer metal accumulation time. In addition, it was noted that the Pb content in the ancient garden substantially increased from the inner parts (154 ppm) to the periphery (322 ppm) near streets with car traffic. This is noteworthy because the five Salón plots had soils extremely homogeneous (carbonates: 24-25%, clay: 18-19%, pH: 7.6-7.7, organic matter: 3-4%, free iron 0.6-0.7%). Despite this seeming soil contamination in Pb, Cr, Cu, Zn, and Cd from urban sources, there were no toxic levels according to European legislation and consequently, there should be no health risk.

Delgado, Gabriel; Sánchez-Marañón, Manuel; Bech, Jaume; Sartini, Alessandra; Martín-García, Juan Manuel; Delgado, Rafael

2013-04-01

425

Wastewaters at SRS where heavy metals are a potential problem  

SciTech Connect

The principal objective of this report is to identify and prioritize heavy metal-containing wastewaters at the Savannah River Site (SRS) in terms of their suitability for testing of and clean-up by a novel bioremediation process being developed by SRTC. This process involves the use of algal biomass for sequestering heavy metal and radionuclides from wastewaters. Two categories of SRS wastewaters were considered for this investigation: (1) waste sites (primarily non-contained wastes managed by Environmental Restoration), and (2) waste streams (primarily contained wastes managed by Waste Management). An attempt was made to evaluate all sources of both categories of waste throughout the site so that rational decisions could be made with regard to selecting the most appropriate wastewaters for present study and potential future treatment. The investigation included a review of information on surface and/or groundwater associated with all known SRS waste sites, as well as waters associated with all known SRS waste streams. Following the initial review, wastewaters known or suspected to contain potentially problematic concentrations of one or more of the toxic metals were given further consideration.

Wilde, E.W.; Radway, J.C.

1994-11-01

426

Heavy metals in edible seaweeds commercialised for human consumption  

NASA Astrophysics Data System (ADS)

Though seaweed consumption is growing steadily across Europe, relatively few studies have reported on the quantities of heavy metals they contain and/or their potential effects on the population's health. This study focuses on the first topic and analyses the concentrations of six typical heavy metals (Cd, Pb, Hg, Cu, Zn, total As and inorganic As) in 52 samples from 11 algae-based products commercialised in Spain for direct human consumption ( Gelidium spp.; Eisenia bicyclis; Himanthalia elongata; Hizikia fusiforme; Laminaria spp.; Ulva rigida; Chondrus crispus; Porphyra umbilicales and Undaria pinnatifida). Samples were ground, homogenised and quantified by atomic absorption spectrometry (Cu and Zn by flame AAS; Cd, Pb and total As by electrothermal AAS; total mercury by the cold vapour technique; and inorganic As by flame-hydride generation). Accuracy was assessed by participation in periodic QUASIMEME (Quality Assurance of Information in Marine Environmental Monitoring in Europe) and IAEA (International Atomic Energy Agency) intercalibration exercises. To detect any objective differences existing between the seaweeds' metal concentrations, univariate and multivariate studies (principal component analysis, cluster analysis and linear discriminant analysis) were performed. It is concluded that the Hizikia fusiforme samples contained the highest values of total and inorganic As and that most Cd concentrations exceeded the French Legislation. The two harvesting areas (Atlantic and Pacific oceans) were differentiated using both univariate studies (for Cu, total As, Hg and Zn) and a multivariate discriminant function (which includes Zn, Cu and Pb).

Besada, Victoria; Andrade, José Manuel; Schultze, Fernando; González, Juan José

2009-01-01

427

Magnetic mineralogy of heavy metals-contaminated soils  

NASA Astrophysics Data System (ADS)

Soils around mine and in urban areas are often contaminated by heavy metals derived from industrial and human activities [1, 2]. These contaminated soils are often characterized by a magnetic enhancement on topsoils. Many studies demonstrated that there are significant correlations between heavy metals and various magnetic parameters in contaminated soils, indicating a strong affinity of heavy metals to magnetic minerals. The magnetic particles in contaminated soils were separated by a magnetic separation technique. The rock magnetism, XRD, field emission scanning electron microscopy equiped with an energy-dispersive X-ray analyzer (FESEM/EDX) were used to characterize their magnetic mineralogy. Results of XRD analysis indicated that the magnetic particles separated from heavy metal-contaminated soils are composed of quartz, magnetite, and hematite. Based on the X-ray diffraction peak intensity, the Fe3O4 was identified as the predominant magnetic mineral phase. The high-temperature magnetization (Ms-T) curves of magnetic particles extracted from contaminated soils show a sharp Ms decrease at about 580C (the Curie temperature of magnetite), suggesting that magnetite is the dominant magnetic carrier. The hysteresis loops of contaminated soils are closed at about 100-200 mT which is consistent with the presence of a dominant ferrimagnetic mineral phase. The FESEM analysis showed a great variety of shapes of magnetic particles in contaminated soils. The most common morphology are observed in the form of spherules, with the sizes ranging from 20 to 100 um. The chemical composition of magnetic particles consist mainly of Fe, Si, Al, and Ca with minor heavy metal elements (Cu, Zn, Hg, and Cr). The semi-quantitative Fe content identified by FESEM/EDX ranged from 40 to 90%. Combined studies of rock magnetism, XRD, and FESEM/EDX indicated that magnetic mineral phases responsible for the magnetic enhancement of contaminated soils are anthropogenic origin which are coarse-grained multi-domain (MD) ferrimagnetic minerals. These spherical magnetic particles in contaminated soils are most likely related to airborne particles from coal combusition and industrial activities. Coal burning, metallurgical and industrial dusts contain a significant fraction of ferrimagnetic minerals. The magnetic particles in fly ash from coal-burning power plant have a typical spherical morphology, ranging from 10 to 100 ?m. Vehicle emissions have been suggested to be another source of magnetic particles. These anthropogenic ferrimagnetic mineral phases are directly responsible for the magnetic enhancement in the contaminated soils. Therefore, the strong magnetic signature in contaminated soils can be used as an effective tool for identifying pollution sources and quantifying pollution level of heavy metals. Acknowledgements: This research was supported by National Nature Science Foundation of China (No. 41171182 and 40971131) and the Ph.D. Programs Foundation of Ministry of Education of China (20090101110088). [1] Lu, S.G. & Bai, S.Q. (2006) J. Appl. Geophys., 60, 1-12. [2] Lu, S.G., Bai, S.Q. & Xue, Q.F. (2007) Geophys. J. Inter., 171, 568-580.

Shenggao, L.

2012-04-01

428

Heavy metal pollution and assessment in the tidal flat sediments of Haizhou Bay, China.  

PubMed

The heavy metal inventory and the ecological risk of the tidal flat sediments in Haizhou Bay were investigated. Results show that the average concentrations of heavy metals in the surface sediments exceeded the environment background values of Jiangsu Province coastal soil, suggesting that the surface sediments were mainly polluted by heavy metals (Cd, Cr, Cu, Mn, Pb and Zn). In addition, the profiles of heavy metals fluxes can reflect the socio-economic development of Lianyungang City, and heavy metals inputs were attributed to anthropogenic activities. Cr, Cu, Pb and Zn were mainly present in the non-bioavailable residual form in surface sediments, whereas Cd and Mn were predominantly in the highly mobile acid soluble and reducible fractions. The ecological risk of the polluted sediments stemmed mainly from Cd and Pb. According to the Sediment quality guidelines (SQGs), however, the adverse biological effects caused by the heavy metals occasionally occurred in tidal flat. PMID:23820195

Zhang, Rui; Zhou, Li; Zhang, Fan; Ding, Yingjun; Gao, Jinrong; Chen, Jing; Yan, Hongqiang; Shao, Wei

2013-09-15

429

Accumulation rates of airborne heavy metals in wetlands  

USGS Publications Warehouse

Accumulation rates of heavy metals (Cd, Cr, Cu, Mn, Pb, and Zn) retained in wetland sediments in northwest Indiana-downwind of the Chicago-Gary-Hammond industrial area-are quantified to assess anthropogenic influences on atmospheric fluxes. Metal concentrations for 22 sediment cores are determined by ICP-AES after ashing and strong acid extraction. Relations between organic content and metal concentrations at depth are used to separate natural and anthropogenic sources. Accumulation rates over the lifetime of the wetlands (???4500 years) have averaged 0.2 (Cd), 1.4 (Cu), 1.7 (Cr), 13.4 (Mn), 4.8 (Pb), and 18.7 (Zn) mg m-2 y-1. Rates for the last 100 years have increased on average by factors of 6 (Cd), 8 (Cu), 10 (Mn), 15 (Pb), and 30 (Zn), remaining effectively constant for Cr. Where the wetlands have been drained, metals have been lost from the sediments, owing to changes in organic content and local hydrochemistry (exposure to acidic rainfall). Sediment-based accumulation rates at the undrained sites are higher, though generally consistent, with measured and modeled atmospheric fluxes documented by short-term studies conducted over the last three decades. The fraction of the total metals in the wetlands estimated to be of anthropogenic origin ranges from approximately 3% for Cr, up to approximately 35% for Pb, and 70% for Zn. This historic legacy of contamination must be considered in land management decisions, particularly when wetlands are drained.

Souch, C.J.; Filippelli, G.M.; Dollar, N.; Perkins, S.; Mastalerz, M.

2002-01-01

430

[Heavy metal concentrations in mosses from Qiyi Glacier region].  

PubMed

Heavy metal (Cr, Fe, Cu, Zn, As, Cd and Pb) concentrations were measured in 17 moss samples which were collected at Qiyi Glacier Region in July, August and September, 2009 in a preliminary investigation of heavy metal pollution situation in this area. The results indicated that heavy metal concentrations in mosses were relatively high and concentrations of Fe were at the highest level (varied between 15 160.00 and 34 960.00 microg x g(-1)), followed by Zn, Cu, Cr, Pb, As, with average concentrations of 169.56, 134.81, 34.52, 26.16, 9.15 microg x g(-1). Enrichment factor analysis and correlation analysis indicated that Fe and Cr in mosses mainly stemmed from crustal dust, and concentrations of Cu, Pb, Zn and Cd were influenced by human activities; As was moderately enriched which means As in mosses was mainly originated from anthropogenic pollution. According to the Global Data Assimilation System (GDAS) meteorological data from the National Center for Environmental Prediction (NCEP) of 2009 and the simulation of the HYSPLIT v4.9 Model on 3-dimension back trajectories of air mass at Qiyi glacier district, several trajectories reflecting the main characteristics of air flow were obtained based on the classification of cluster analysis on the hundreds of back trajectories. The back trajectories revealed that atmospheric transport characteristics in the study area changed obviously by season. Compared to Spring and Autumn, atmospheric transmission sources were relatively more in Winter and Summer. The main sources of atmospheric pollutants in Qiyi Glacier region were transported from Jiuquan and Jiayuguan regions. PMID:25158478

Ma, Juan-Juan; Li, Zhen

2014-06-01

431

Heavy metals in wild rice from northern Wisconsin  

USGS Publications Warehouse

Wild rice grain samples from various parts of the world have been found to have elevated concentrations of heavy metals, raising concern for potential effects on human health. It was hypothesized that wild rice from north-central Wisconsin could potentially have elevated concentrations of some heavy metals because of possible exposure to these elements from the atmosphere or from water and sediments. In addition, no studies of heavy metals in wild rice from Wisconsin had been performed, and a baseline study was needed for future comparisons. Wild rice plants were collected from four areas in Bayfield, Forest, Langlade, Oneida, Sawyer and Wood Counties in September, 1997 and 1998 and divided into four plant parts for elemental analyses: roots, stems, leaves and seeds. A total of 194 samples from 51 plants were analyzed across the localities, with an average of 49 samples per part depending on the element. Samples were cleaned of soil, wet digested, and analyzed by ICP for Ag, As, Cd, Cr, Cu, Hg, Mg, Pb, Se and Zn. Roots contained the highest concentrations of Ag, As, Cd, Cr, Hg, Pb, and Se. Copper was highest in both roots and seeds, while Zn was highest just in seeds. Magnesium was highest in leaves. Seed baseline ranges for the 10 elements were established using the 95% confidence intervals of the medians. Wild rice plants from northern Wisconsin had normal levels of the nutritional elements Cu, Mg and Zn in the seeds. Silver, Cd, Hg, Cr, and Se were very low in concentration or within normal limits for food plants. Arsenic and Pb, however, were elevated and could pose a problem for human health. The pathway for As, Hg and Pb to the plants could be atmospheric.

Bennett, J.P.; Chiriboga, E.; Coleman, J.; Waller, D.M.

2000-01-01

432

Representing soil pollution by heavy metals using continuous limitation scores  

NASA Astrophysics Data System (ADS)

The paper suggests a methodology to represent overall soil pollution in a sampled area using continuous limitation scores. The interpolated heavy metal concentrations are first transformed to limitation scores using the exponential transfer function determined by using two threshold values: permissible concentration (0 limitation points) and seriously polluted soil (4 limitation points). The limitation scores can then be summed to produce the map of cumulative limitation scores and visualize the most critically polluted areas. The methodology was illustrated using the 784 soil samples analyzed for Cd, Cr, Cu, Ni, Pb and Zn in the central region of Croatia. The samples were taken at 1×1 and 2×2 km grids and at fixed depths of 20 cm. Heavy metal concentrations in soil were determined by ICP-OES after microwave assisted aqua regia digestion. The sampled concentrations were interpolated using block regression-kriging with geology and land cover maps, terrain parameters and industrialization parameters as auxiliary predictors. The results showed that the best auxiliary predictors are geological map, ground water depth, NDVI and slope map and distance to urban areas. The spatial prediction was satisfactory for Cd, Ni, Pb and Zn, and somewhat less satisfactory for Cu and Cr. The final map of cumulative limitation scores showed that 33.5% of the total area is suitable for organic agriculture and 7.2% of the total area is seriously polluted by one or more heavy metals. This procedure can be used to assess suitability of soils for agricultural production and as a basis for possible legal commitments to maintain the soil quality.

Romi?, Marija; Hengl, Tomislav; Romi?, Davor; Husnjak, Stjepan

2007-10-01

433

Heavy metal contamination of vegetables in Isfahan, Iran  

PubMed Central

Vegetables are an inevitable and important part of a healthy and balanced diet. They could be contaminated by heavy metals in many ways including irrigation by sewage water and industrial effluents sewage sludge, vehicular emissions, industrial waste and atmospheric deposition. In this study, we sought to determine if some vegetables (cucumbers, tomatoes, cabbage, lettuce, potatoes, onions, carrots, persian leeks, dill, spinach, coriander, parsley) grown locally in the suburban of Isfahan city and sold in the urban markets are contaminated with cadmium (Cd), chromium (Cr) and lead (Pb). Vegetables were sampled from August to October 2010. After washing, they were oven-dried and digested using three-acid mixture (70% HNO3, 65% HClO4 and 70% H2SO4). Analyzes of the heavy metals was performed using atomic absorption spectrophotometry. To validate the assay method, intra-day and inter-day variation studies were performed. The concentrations (?g/g) of heavy metals in the samples ranged from 0.00 to 3.66 for Cd, 0.00 to 6.00 for Cr and 0.00 to 7.14 for Pb. The highest concentration of heavy metals was for Pb. The results showed that the amount of Cd, Cr and Pb of some samples exceeded the recommended levels. The amount of Cd in cucumber, tomatoes, potatoes with skin, carrots, and spinach was significantly higher in the samples collected from Isfahanak, Dashti and Ilchi farms than those of Dorche farms. Also, the amount of Cr in onion, carrots, and spinach was significantly higher in samples collected from Isfahanak, Dashti and Ilchi farms than those of Dorche farms. However, the amount of Pb in the carrots and leek was significantly higher in the samples collected from Dorche farms than those of Isfahanak, Dashti and Ilchi farms. It can be concluded from the findings of this study that the amounts of Cd, Cr, and Pb were higher than the acceptable levels recommended by WHO/FAO. Also, higher amount of Cd and Cr in some samples collected from Isfahanak, Dashti and Ilchi farms compared to that of the samples collected from Dorche farms may indicate the influence of contaminants that enter ZayadeRood River as it passes Isfahan. PMID:24459476

Jafarian-Dehkordi, A.; Alehashem, M.

2013-01-01

434

Occurrence and toxicology of heavy metals in Chesapeake Bay waterfowl  

SciTech Connect

The goals of this study were to elucidate relationships between food habits and tissue accumulations of heavy metals in Chesapeake Bay waterfowl and to determine effects of chronic cadmium and lead ingestion on energy metabolism in waterfowl. In combination with an imposed food restriction, cadmium ingestion appeared to alter some indices of energy metabolism, such as plasma concentrations of free fatty acids and triiodothyronine, at dietary cadmium levels far below those eliciting similar responses in the absence of a food restriction. Those results suggest the importance of considering interactions with other stressors when examining potential effects of environmental contaminants on wild animals.

Di Giulio, R.T.

1982-01-01

435

Heavy metal contamination of vegetables in Isfahan, Iran.  

PubMed

Vegetables are an inevitable and important part of a healthy and balanced diet. They could be contaminated by heavy metals in many ways including irrigation by sewage water and industrial effluents sewage sludge, vehicular emissions, industrial waste and atmospheric deposition. In this study, we sought to determine if some vegetables (cucumbers, tomatoes, cabbage, lettuce, potatoes, onions, carrots, persian leeks, dill, spinach, coriander, parsley) grown locally in the suburban of Isfahan city and sold in the urban markets are contaminated with cadmium (Cd), chromium (Cr) and lead (Pb). Vegetables were sampled from August to October 2010. After washing, they were oven-dried and digested using three-acid mixture (70% HNO3, 65% HClO4 and 70% H2SO4). Analyzes of the heavy metals was performed using atomic absorption spectrophotometry. To validate the assay method, intra-day and inter-day variation studies were performed. The concentrations (?g/g) of heavy metals in the samples ranged from 0.00 to 3.66 for Cd, 0.00 to 6.00 for Cr and 0.00 to 7.14 for Pb. The highest concentration of heavy metals was for Pb. The results showed that the amount of Cd, Cr and Pb of some samples exceeded the recommended levels. The amount of Cd in cucumber, tomatoes, potatoes with skin, carrots, and spinach was significantly higher in the samples collected from Isfahanak, Dashti and Ilchi farms than those of Dorche farms. Also, the amount of Cr in onion, carrots, and spinach was significantly higher in samples collected from Isfahanak, Dashti and Ilchi farms than those of Dorche farms. However, the amount of Pb in the carrots and leek was significantly higher in the samples collected from Dorche farms than those of Isfahanak, Dashti and Ilchi farms. It can be concluded from the findings of this study that the amounts of Cd, Cr, and Pb were higher than the acceptable levels recommended by WHO/FAO. Also, higher amount of Cd and Cr in some samples collected from Isfahanak, Dashti and Ilchi farms compared to that of the samples collected from Dorche farms may indicate the influence of contaminants that enter ZayadeRood River as it passes Isfahan. PMID:24459476

Jafarian-Dehkordi, A; Alehashem, M

2013-01-01

436

Immobilization of heavy metals by calcium sulfoaluminate cement  

Microsoft Academic Search

Two types of calcium sulfoaluminate cement containing 20% and 30% phosphogypsum, respectively, were investigated for their ability in hazardous waste stabilization. Fourteen series of pastes were prepared, each containing the following soluble salt: NaâCrOâ.4HâO; NaâCrâOâ.2HâO; CrClâ.6HâO; Pb(NOâ)â; Zn(NOâ)â.6HâO; ZnSOâ.7HâO; and CdClâ.5H2O. The level of pollution was 0.069 mol of heavy metal per Kg of cement. The study has been carried

S. Peysson; J.. Pera; M. Chabannet

2005-01-01

437

Streptomyces communities in soils polluted with heavy metals  

NASA Astrophysics Data System (ADS)

The contents of differently mobile heavy metal compounds and their influence on the formation of microbial cenoses (particularly, streptomyces communities) in technogenically disturbed soils are considered. Elevated concentrations of mobile Cu, Zn, Ni, Cd, and Fe compounds are shown to determine structural-functional changes in microbial cenoses that are displayed in a decreasing number of microorganisms and a narrower spectrum of the streptomyces species. Some specific features of the formation of streptomyces communities in technogenic soils were revealed on the basis of the analysis of their species structure with the use of the Margalef, Berger-Parker, and Sorensen indices of biodiversity.

Grishko, V. N.; Syshchikova, O. V.

2009-02-01

438

Heavy metal tolerance and metal homeostasis in Pseudomonas putida as revealed by complete genome analysis.  

PubMed

The genome of Pseudomonas putida KT2440 encodes an unexpected capacity to tolerate heavy metals and metalloids. The availability of the complete chromosomal sequence allowed the categorization of 61 open reading frames likely to be involved in metal tolerance or homeostasis, plus seven more possibly involved in metal resistance mechanisms. Some systems appeared to be duplicated. These might perform redundant functions or be involved in tolerance to different metals. In total, P. putida was found to bear two systems for arsenic (arsRBCH), one for chromate (chrA), four to six systems for divalent cations (two cadA and two to four czc chemiosmotic antiporters), two systems for monovalent cations: pacS, cusCBA (plus one cryptic silP gene containing a frameshift mutation), two operons for Cu chelation (copAB), one metallothionein for metal(loid) binding, one system for Te/Se methylation (tpmT) and four ABC transporters for the uptake of essential Zn, Mn, Mo and Ni (one nikABCDE, two znuACB and one mobABC). Some of the metal-related clusters are located in gene islands with atypical genome signatures. The predicted capacity of P. putida to endure exposure to heavy metals is discussed from an evolutionary perspective. PMID:14641571

Cánovas, David; Cases, Ildefonso; de Lorenzo, Víctor

2003-12-01

439

Heavy metal contamination in a vulnerable mangrove swamp in South China.  

PubMed

Concentrations of six heavy metals (Cu, Ni, Zn, Cd, Cr, and Pb) in sediments and fine roots, thick roots, branches, and leaves of six mangrove plant species collected from the Futian mangrove forest, South China were measured. The results show that both the sediments and plants in Futian mangrove ecosystem are moderately contaminated by heavy metals, with the main contaminants being Zn and Cu. All investigated metals showed very similar distribution patterns in the sediments, implying that they had the same anthropogenic source(s). High accumulations of the heavy metals were observed in the root tissues, especially the fine roots, and much lower concentrations in the other organs. This indicates that the roots strongly immobilize the heavy metals and (hence) that mangrove plants possess mechanisms that limit the upward transport of heavy metals and exclude them from sensitive tissues. The growth performance of propagules and 6-month-old seedlings of Bruguiera gymnorhiza in the presence of contaminating Cu and Cd was also examined. The results show that this plant is not sufficiently sensitive to heavy metals after its propagule stage for its regeneration and growth to be significantly affected by heavy metal contamination in the Futian mangrove ecosystem. However, older mangrove seedlings appeared to be more metal-tolerant than the younger seedlings due to their more efficient exclusion mechanism. Thus, the effects of metal contamination on young seedlings should be assessed when evaluating the risks posed by heavy metals in an ecosystem. PMID:23203819

Wang, Yutao; Qiu, Qiu; Xin, Guorong; Yang, Zhongyi; Zheng, Jing; Ye, Zhihong; Li, Shaoshan

2013-07-01

440

[Effect of arbuscular mycorrhizae on growth, heavy metal uptake and accumulation of Zenia insignis Chun seedlings].  

PubMed

To solve the trace metal pollution of a Pd/Zn mine in Hunan province, a greenhouse pot experiment was conducted to investigate the effect of two arbuscular mycorrhizal fungi, Glomus mosseae (Gm) and Glomus intraradices (Gi), on the growth, heavy metal uptake and accumulation of Zenia insignis Chun, the pioneer plant there. The results showed that symbiotic associations were successfully established between the two isolates and Z. insignis in heavy metal contaminated soil. AM fungi improved P absorption, biomass and changed heavy metal uptake and distribution of Z. insignis. AM fungi-inoculated plants had significantly lower Fe, Cu, Zn, Pd concentrations and higher Fe, Cu, Zn, Pd accumulation than non-inoculated plants. However, Gm and Gi showed different mycorrhizal effects on the distribution of heavy metal in hosts, depending on the species of heavy metal. Gi-inoculated Z. insignis showed significantly lower TF values of Fe, Zn, Pd than Gm and non-inoculated plants, while both strains had no effect on TF value of Cu, which indicated that Gi enhanced trace metal accumulation in root system, playing a filtering/sequestering role in the presence of trace metals. The overall results demonstrated that AM fungi had positive effect on Z. insignis in enhancing the ability to adapt the heavy metal contaminated soil and played potential role in the revegetation of heavy metal contaminated soil. But in practical application, the combination of AM, hosts and heavy metal should be considered. PMID:25338391

Li, Xia; Peng, Xia-Wei; Wu, Song-Lin; Li, Zhi-Ru; Feng, Hong-Mei; Jiang, Ze-Ping

2014-08-01

441

Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops  

Microsoft Academic Search

Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in\\u000a areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious\\u000a problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health.\\u000a Heavy metals enter the human

Ejaz ul Islam; Xiao-e Yang; Zhen-li He; Qaisar Mahmood

2007-01-01

442

Application of synthetic principal component analysis model to mine area farmland heavy metal pollution assessment  

Microsoft Academic Search

Referring to GB5618-1995 about heavy metal pollution, and using statistical analysis SPSS, the major pollutants of mine area\\u000a farmland heavy metal pollution were identified by variable clustering analysis. Assessment and classification were done to\\u000a the mine area farmland heavy metal pollution situation by synthetic principal components analysis (PCA). The results show\\u000a that variable clustering analysis is efficient to identify the

Cong-lu Wang; Chao Wu; Wei-jun Wang

2008-01-01

443

Relationship between meteorological variables and total suspended and heavy metal particulates in Little Rock, Arkansas  

E-print Network

concentrations of heavy metals are also toxic to humans. Not only is there an effect on the respiratory system, but such toxicity may also cause brain, kidney, and liver damage (Hwang, 1972; TVA, 1983). Since heavy metals and other particulates may be health... of the requirements for the degree of MASTER OF SCIENCE May 1985 Major Subject: Meteorology RELATIONSHIP BETWEEN METEOROLOGICAL VARIABLES AND TOTAL SUSPENDED AND HEAVY METAL PARTICULATES IN LITTLE ROCK, ARKANSAS A Thesis MARY GWENDOLYN AVERY Approved...

Avery, Mary Gwendolyn

1985-01-01

444

Spatial distribution of heavy metals in surficial sediments from Guanabara Bay: Rio de Janeiro, Brazil  

Microsoft Academic Search

Ninety-two surface sediment samples were collected in Guanabara Bay, one of the most prominent urban bays in SE Brazil, to\\u000a investigate the spatial distribution of anthropogenic pollutants. The concentrations of heavy metals, organic carbon and particle\\u000a size were examined in all samples. Large spatial variations of heavy metals and particle size were observed. The highest concentrations\\u000a of heavy metals were

José Antônio Baptista Neto; Franz Xaver Gingele; Thomas Leipe; Isa Brehme

2006-01-01

445

Effect of heavy metal salts on the life history of Daphnia similis Claus (Crustacea: Cladocera)  

Microsoft Academic Search

The acute toxicity of heavy metal salts onDaphnia similis Claus is studied in terms of LC50. Copper is found to be the most toxic and zinc the least. Toxicity of the heavy metals is studied by observing changes in\\u000a the longevity, body length, fecundity and moulting frequency of the animal. The decreasing order of toxicity of heavy metals\\u000a on the

Sudha Soundrapandian; K Venkataraman

1990-01-01

446

An Effective Means of Biofiltration of Heavy Metal Contaminated Water Bodies Using Aquatic Weed Eichhornia crassipes  

Microsoft Academic Search

Various aquatic plant species are known to accumulate heavy metals through the process of bioaccumulation. World’s most troublesome\\u000a aquatic weed water hyacinth (Eichhornia crassipes) has been studied for its tendency to bio-accumulate and bio-magnify the heavy metal contaminants present in water bodies.\\u000a The chemical investigation of plant parts has shown that it accumulates heavy metals like lead (Pb), chromium (Cr),

Suchi Tiwari; Savita Dixit; Neelam Verma

2007-01-01

447

Effect of heavy metal pollution on mycorrhizal colonization and function: physiological, ecological and applied aspects  

Microsoft Academic Search

High concentrations of heavy metals in soil have an adverse effect on micro-organisms and microbial processes. Among soil\\u000a microorganisms, mycorrhizal fungi are the only ones providing a direct link between soil and roots, and can therefore be of\\u000a great importance in heavy metal availability and toxicity to plants. This review discusses various aspects of the interactions\\u000a between heavy metals and

C. Leyval; K. Turnau; K. Haselwandter

1997-01-01

448

Adsorption Behaviors of Heavy Metal Ions by Steel Slag-An Industrial Solidwaste  

Microsoft Academic Search

Batch experiments were carried out to investigate heavy metal ions adsorption properties of steel slag, the results showed that steel slag could be used as an effective adsorbent to removal heavy metals such as Cr3+,Cu2+,Pb2+and Zn2+ from the aqueous solution. For the heavy metal Cr3+, the removal yield increased with increasing contact time and reached the equilibrium state within lh;

Sheng-Yu Liu; Jin Gao; Bin Qu; Yi-jin Yang

2009-01-01

449

Heavy metal removal by combining anaerobic upflow packed bed reactors with water hyacinth ponds  

Microsoft Academic Search

The removal of four selected heavy metals (Cu, Cd, Pb and Zn) has been assessed in an upflow anaerobic packed bed reactor filled with porous volcanic rock as an adsorbent and an attachment surface for bacterial growth. Two different feeding regimes were applied using low (5 mg L of heavy metal each) and high (10 mg L of heavy metal each) strength wastewater. After

Christian Birame Sekomo; Vedaste Kagisha; Diederik Rousseau; Piet Lens

2012-01-01

450

Assessment of interference in biosorption of a heavy metal  

SciTech Connect

Biosorption of heavy metals by various biological materials has been studied extensively in the last decade due to its potential particularly in wastewater treatment. The presence of a large number of metals in industrial metal-bearing solutions makes it necessary to investigate their effect on the final metal uptake by individual biosorbent materials. Nonliving biomass of Sargassum, a brown marine alga, is capable of binding more than 10% of its dry weight in toxic cadmium ions. Although ubiquitous iron interferes with Cd uptake, only approximately 4.5% of it is sequestered (biomass dry weight). Biosorption of both metals at pH 4.5 could be described by Langmuir-type isotherms with b, the affinity-related coefficient (Cd: b = 0.015; Fe: b = 0.027). The interference of Fe with Cd uptake, and vice versa, was assessed by deriving three-dimensional equilibrium two-metal sorption isotherm surfaces, smoothed and cut to reveal the inhibition effect of Fe on biosorption of Cd: at the equilibrium concentration Cf[Cd] = 1.5 mM, the presence of Fe at 1.5 mM equilibrium concentration suppressed the Cd uptake to only 76% of the original value. For 50% Cd uptake reduction, a very high equilibrium Fe presence of 4.5 mM was required. The Cd presence affected the uptake of Fe very strongly. To obtain equal values of uptake for each metal in the biosorbent, the ratio of equilibrium concentrations of 0.42 Cd to 1 Fe is necessary in the liquid phase.

Figueira, M.M. [McGill Univ., Montreal, Quebec (Canada). Dept. of Chemical Engineering] [McGill Univ., Montreal, Quebec (Canada). Dept. of Chemical Engineering; [Univ. Federal de Minas Gerais, Belo Horizonte (Brazil). Dept. of Metallurgical Engineering; Volesky, B. [McGill Univ., Montreal, Quebec (Canada). Dept. of Chemical Engineering] [McGill Univ., Montreal, Quebec (Canada). Dept. of Chemical Engineering; Ciminelli, V.S.T. [Univ. Federal de Minas Gerais, Belo Horizonte (Brazil). Dept. of Metallurgical Engineering] [Univ. Federal de Minas Gerais, Belo Horizonte (Brazil). Dept. of Metallurgical Engineering

1997-05-20

451

An effective means of biofiltration of heavy metal contaminated water bodies using aquatic weed Eichhornia crassipes.  

PubMed

Various aquatic plant species are known to accumulate heavy metals through the process of bioaccumulation. World's most troublesome aquatic weed water hyacinth (Eichhornia crassipes) has been studied for its tendency to bio-accumulate and bio-magnify the heavy metal contaminants present in water bodies. The chemical investigation of plant parts has shown that it accumulates heavy metals like lead (Pb), chromium (Cr), zinc (Zn), manganese (Mn) and copper (Cu) to a large extent. Of all the heavy metals studied Pb, Zn and Mn tend to show greater affinity towards bioaccumulation. The higher concentration of metal in the aquatic weed signifies the biomagnification that lead to filtration of metallic ions from polluted water. The concept that E. crassipes can be used as a natural aquatic treatment system in the uptake of heavy metals is explored. PMID:17072557

Tiwari, Suchi; Dixit, Savita; Verma, Neelam

2007-06-01

452

Heavy metals contamination of soils surrounding waste deposits in Romania  

NASA Astrophysics Data System (ADS)

Soils contamination with heavy metals is one of the most severe aspects of environmental pollution in Romania, independently of the origin sources (domestic or industrial activities) or type of disposal (organised landfill or hazardous deposits)[l-2]. This fact is the consequence of the poor state of the existing waste deposits in Romania and of the significant costs involved by the establishing of a new landfill according with the international regulations. The present study is trying to emphasise the contamination of soils surrounding different categories of waste deposits (sewage sludge ponds, domestic and industrial waste landfills, hillocks, sterile deposits) from various regions of Romania. Some case studies show a special interest being localise in a protected area (Iron Gates Natural Park). In order to quantify the concentration of metals like Cd, Cr, Cu, Pb, Zn, Ni, Mo in soil samples, analysis were performed using Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES). Romanian standards were used as reference values[3].

Matache, M.; Rozylowicz, L.; Ropota, M.; Patroescu, C.

2003-05-01

453

Use of dried aquatic plant roots to adsorb heavy metals  

SciTech Connect

The removal of heavy metal ions by dried aquatic macrophytes was investigated. The ability of the biomass, Eichhornia crassipes (water hyacinth), Typha latifolia (cattail), Sparganium minimum (burr reed) and Menyanthes trifoliata to abstract lead and mercury ions is presented here, along with a conceptual filter design. This paper examines an alternative to both the traditional and recent systems designed for metal removal. It involves the use of dried aquatic macrophytes. There are numerous advantages for the use of dried macrophytes in the treatment of industrial wastewater. First, it is cost-effective. There are also funding opportunities through a variety of Environmental Protection Agency`s (EPA) programs. It is more environmentally conscious because a wetland, the harvesting pond, has been created. And, it creates public goodwill by providing a more appealing, less hardware-intensive, natural system.

Robichaud, K.D.

1996-12-31

454

Natural and technogenic compounds of heavy metals in soils  

NASA Astrophysics Data System (ADS)

The existing geological classification of heavy metals (HMs) is not suitable for their characterization in soils. The carriers of HMs in soils differ from those in the lithosphere. These are clay minerals; iron oxides, whose composition varies between the background and urban soils; various manganese oxides; and different groups of organic substances. The mineral composition of HM carriers can vary significantly. The main iron oxides are ferrihydrite, goethite, feroxyhyte, and lepidocrocite in the background soils and technogenic magnetite in the urban soils. The different structures of manganese oxides determine their affinity for specific HMs. Metallic iron and green rust are very efficient in artificial geochemical barriers, although they act as strong reducers there. HM compounds strongly vary in soils because of the unstable conditions.

Vodyanitskii, Yu. N.

2014-04-01

455

Handheld colorimeter for determination of heavy metal concentrations  

NASA Astrophysics Data System (ADS)

A portable instrument that measures heavy metal concentration from a colorimetric sensor array is presented. The use of eight sensing membranes, placed on a plastic support, allows to obtain the hue component of the HSV colour space of each one in order to determinate the concentration of metals present in a solution. The developed microcontroller-based system captures, in an ambient light environment, an image of the sensor array using an integrated micro-camera and shows the picture in a touch micro-LCD screen which acts as user interface. After image-processing of the regions of interest selected by the user, colour and concentration information are displayed on the screen.

López Ruiz, N.; Ariza, M.; Martínez Olmos, A.; Vukovic, J.; Palma, A. J.; Capitan-Vallvey, L. F.

2011-08-01

456

Determination of heavy metals in soil and different parts of Diplazium esculentum (medicinal fern)  

NASA Astrophysics Data System (ADS)

Diplazium esculentum is a widely used medicinal fern in Malaysia and other regions worldwide. Heavy metals in plants should be determined because prolonged human intake of toxic trace elements, even at low doses, results in organ malfunction and causes chronic toxicity. Hence, substantial information should be obtained from plants that grow on soils containing high concentrations of heavy metals. This study aimed to determine the physicochemical characteristics of soil and heavy metal concentrations (Pb, Cr, Mn, Cu, and Zn) in different parts of D. esculentum and soil, which were collected from the fern garden of Universiti Kebangsaan Malaysia. Results showed that heavy metals were highly accumulated in D. esculentum roots.

Jasim, Hind S.; Idris, Mushrifah; Abdullah, Aminah; Kadhum, A. A. H.

2014-09-01

457

BASELINE STUDY OF HEAVY METAL CONCENTRATIONS AND HUMAN ACTIVITY IMPACT ANALYSIS IN THE HAWAIIAN  

E-print Network

BASELINE STUDY OF HEAVY METAL CONCENTRATIONS AND HUMAN ACTIVITY IMPACT ANALYSIS IN THE HAWAIIAN.Continentalsilicatedustalsomakea lesscontributionto thevariationof elementalcompoaitiondowncore.Thebaselineof heavymetalsin theunimpactedHawaiian

Luther, Douglas S.

458

Method of removal of heavy metal from molten salt in IFR fuel pyroprocessing  

DOEpatents

An electrochemical method of separating heavy metal values from a radioactive molten salt including Li halide at temperatures of about 500.degree. C. The method comprises positioning a solid Li--Cd alloy anode in the molten salt containing the heavy metal values, positioning a Cd-containing cathode or a solid cathode positioned above a catch crucible in the molten salt to recover the heavy metal values, establishing a voltage drop between the anode and the cathode to deposit material at the cathode to reduce the concentration of heavy metals in the salt, and controlling the deposition rate at the cathode by controlling the current between the anode and cathode.

Gay, Eddie C. (Park Forest, IL)

1995-01-01

459

Changes of Heavy Metals in Pollutant Release and Transfer Registers (PRTRs) in Korea  

PubMed Central

Industrial effluent containing heavy metals discharged into streams may pose high toxicity risks to aquatic organisms and to human health. Therefore, it is important to understand how to change the amount of effluent with heavy metals discharged from industries into open aquatic ecosystems both for effective management of heavy metals and to foster sustainable ecosystems. This study was conducted to characterize the release of heavy metals from industries based on the Pollutant Release and Transfer Registers database in Korea from 1999 to 2010. From the database, we selected nine heavy metals (Pb, Cd, Mn, Sb, Cu, Zn, Cr, Sn, and Ni) and compared the differences in their effluent for different types of industries. The heavy metal effluents released into freshwater ecosystems were classified into four clusters through the learning process of the self-organizing map. Cluster 1 was characterized by the relatively higher effluent volumes of heavy metals, whereas cluster 4 had lower effluent volumes. The different patterns of the effluent volumes in heavy metals were closely associated with the differences of industrial types, and the changes of effluents of heavy metals reflected the changes in regulations and laws for aquatic ecosystem management. PMID:24577281

Kwon, Yong-Su; Bae, Mi-Jung; Park, Young-Seuk

2014-01-01

460

Heavy metals in water, sediments and submerged macrophytes in ponds around the Dianchi Lake, China.  

PubMed

Through retaining runoff and pollutants such as heavy metals from surrounding landscapes, ponds around a lake play an important role in mitigating the impacts of human activities on lake ecosystems. In order to determine the potential for heavy metal accumulation of submerged macrophytes, we investigated the concentrations of 10 heavy metals (i.e., As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in water, sediments, and submerged macrophytes collected from 37 ponds around the Dianchi Lake in China. Our results showed that both water and sediments of these ponds were polluted by Pb. Water and sediments heavy metal concentrations in ponds received urban and agricultural runoff were not significantly higher than those in ponds received forest runoff. This result indicates that a large portion of heavy metals in these ponds may originate from atmospheric deposition and weathering of background soils. Positive relationships were found among heavy metal concentrations in submerged macrophytes, probably due to the coaccumulation of heavy metals. For most heavy metals, no significant relationships were found between submerged macrophytes and their water and sediment environments. The maximum concentrations of Cr, Fe and Ni in Ceratophyllum demersum were 4242, 16,429 and 2662mgkg(-1), respectively. The result suggests that C. demersum is a good candidate species for removing heavy metals from polluted aquatic environments. PMID:25011115

Wang, Zhixiu; Yao, Lu; Liu, Guihua; Liu, Wenzhi

2014-09-01

461

Heavy metals processing near-net-forming summary progress report  

SciTech Connect

This study utilized a converging-diverging nozzle to spray-form an alloy having a weight percent composition of 49.6% iron, 49.6% tungsten, and 0.8% carbon into samples for analysis. The alloy was a surrogate that displayed metallurgical characteristics similar to the alloys used in the heavy metals processing industry. US DOE facilities are evaluating advanced technologies which can simplify component fabrication, reduce handling steps, and minimize final machining. The goal of producing net-shaped components can be approached from several directions. In spray forming, molten metal is converted by a nozzle into a plume of fine droplets which quickly cool in flight and solidify against a substrate. The near-final dimension product that is formed receives additional benefits from rapid solidification. This single-step processing approach would aid the heavy metals industry by streamlining fabrication, improving production yields, and minimizing the generation of processing wastes. This Program effort provided a large selection of as-sprayed specimens. These samples were sprayed with gas-to-metal mass ratios ranging from 0.8:1 to 4:1. Samples targeted for analysis were produced from different spray conditions. Metallography on some samples revealed areas that were fully dense and homogeneous at 5,000X. These areas averaged grain sizes of 1 micron diameter. Other samples when viewed at 2,000X were highly segregated in the 10 micron diameter range. Deposit efficiencies of greater than 90% were demonstrated using the untailored spray system. Discharge gases were analyzed and two categories of particles were identified. One category of particle had a chemical composition characteristic of the alloy being sprayed and the second type of particle had a chemical composition characteristic of the ceramics used in the spray system component fabrication. Particles ranged in size from 0.07 to 3 microns in diameter. 8 refs., 67 figs., 20 tabs.

Watson, L.D. [Custom Spray Technologies, Inc., Rigby, ID (United States); Thompson, J.E. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1994-09-01

462

Mapping of available heavy metals in Catamarca (Argentina)  

NASA Astrophysics Data System (ADS)

Copper, iron, manganese and zinc are four essential elements for plant growth. Mapping heavy metal migration and distribution in soils is a preliminary step in assessing heavy metal availability in soils. However, data of qualitative and quantitative trace elements composition of soils of Argentina are scarce. Despite the small amounts required by plants, agricultural soils are usually deficient in one or more micronutrients, therefore, their concentration in plant tissues falls below the levels that allow optimal growth. Soil nature plays a fundamental role in the availability of micronutrients and their behaviour at a soil-plant level. The aim of this study is to determine the plant availability and areas of deficiency in agricultural soils with risk of salinization. The presented maps have been elaborated on the basis of the information provided by the monochromatic aerial photographs, scale 1:7000 and projected using the topographic information of the National Topographic Maps. Soils were sampled according to the spatial variation of soil types and land use. Sampling points were geo-referenced. Soil samples were analyzed at the laboratory for complete physicochemical and mineralogical characteristics. The percentage of organic matter is the determining factor in the presence and distribution of the available metals in the soils of the studied area, being the top horizon the one of greatest accumulation. CuDTPA, FeDPTA and MnDPTA are mobile within the profile, whereas ZnDPTA remains adsorbed without vertical displacement. ZnDTPA is the only available metal which also shows differences due to soil salinity and textural classes. However, soil geochemical conditions imply low extractability and a certain difficulty for micronutrient absorption by plants.

Roca, N.; Pazos, M. S.; Bech, J.

2009-04-01

463

Chelation: Harnessing and Enhancing Heavy Metal Detoxification—A Review  

PubMed Central

Toxic metals such as arsenic, cadmium, lead, and mercury are ubiquitous, have no beneficial role in human homeostasis, and contribute to noncommunicable chronic diseases. While novel drug targets for chronic disease are eagerly sought, potentially helpful agents that aid in detoxification of toxic elements, chelators, have largely been restricted to overt acute poisoning. Chelation, that is multiple coordination bonds between organic molecules and metals, is very common in the body and at the heart of enzymes with a metal cofactor such as copper or zinc. Peptides glutathione and metallothionein chelate both essential and toxic elements as they are sequestered, transported, and excreted. Enhancing natural chelation detoxification pathways, as well as use of pharmaceutical chelators against heavy metals are reviewed. Historical adverse outcomes with chelators, lessons learned in the art of using them, and successes using chelation to ameliorate renal, cardiovascular, and neurological conditions highlight the need for renewed attention to simple, safe, inexpensive interventions that offer potential to stem the tide of debilitating, expensive chronic disease. PMID:23690738

Sears, Margaret E.

2013-01-01

464

Heavy metals in some soils of Western Georgia  

NASA Astrophysics Data System (ADS)

The results of studying the background content of heavy metals in some soils of Western Georgia are considered. The total contents of chromium, copper, manganese, nickel, lead, and zinc were measured in samples from soil pits located in accordance with a 5-km square grid. The results of the laboratory investigations, which were processed using the statistical methods suggested by Salminen and Baitse, were the basis for the calculation of the background characteristics. Both methods are based on the use of medians that do not reflect the influence of anomalous heavy metal concentrations resulting from the anthropogenic impact, which cannot be avoided even when the locations of the soil pits are carefully chosen. The statistical methods used are compared; the advantage of the Salminen method is shown for soils that are not directly exposed to the influence of pollution sources. The background characteristics obtained are compared to the published ones. A conclusion is reached concerning the possible use of the Salminen method for the soils of Georgia.

Gambashidze, G. O.; Urushadze, T. F.; Blum, W. E.; Mentler, A. F.

2014-08-01

465

Bioindication of heavy metals in soil by liverworts.  

PubMed

Studies were made of the accumulation of the heavy metals Ba, Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb, Sr, V, and Zn and the macroelements N, P, K, Ca, and Mg in liverworts Conocephalum conicum, Marchantia polymorphia, and Pellia epiphylla collected from 57 microhabitats in Poland (Lower Silesia, Tatry Mts., and Puszcza Augustowska forest) and one microhabitat in the Czech Republic (Moravsky Kras). Ecological differentiation of Conocephalum conicum, Marchantia polymorpha and Pellia epiphylla populations is closely correlated with the soil chemistry. The evidence for this assumption are the significant positive correlations between concentrations of elements in soil and in the examined liverworts. In particular, correlations between contents of chromium and cobalt in soil and in Conocephalum conicum and between nickel, chromium, copper, and barium in soil and in Pellia epiphylla prove that these plants can be useful in monitoring of contamination of soil with elements mentioned above. Concentrations of cobalt in almost all the examined liverworts surpass the average background values of this element established for terrestrial bryophytes what proves that these plants tolerate increased accumulated amounts of this element and may therefore act as bioindicator for this heavy metal. Cationic equilibrium of Conocephalum conicum, Marchantia polymorpha and Pellia epiphylla examined according to Czarnowski (1977) pointed to the existence of some disturbances in ionic balance of these plants caused probably by elevated concentrations of microelements (especially iron, cobalt, lead, and copper) in their tissues. PMID:9294244

Samecka-Cymerman, A; Marczonek, A; Kempers, A J

1997-08-01

466

Assessing fly ash treatment: remediation and stabilization of heavy metals.  

PubMed

Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. PMID:21167631

Lima, A T; Ottosen, Lisbeth M; Ribeiro, Alexandra B

2012-03-01

467

Quantum critical points and novel phases in heavy fermion metals  

NASA Astrophysics Data System (ADS)

Quantum criticality arises from competing interactions of correlated systems that favor rivaling ground states. It not only influences physical properties over a wide temperature and parameter ranges, but also gives rise to a plethora of new quantum phases. Magnetic heavy fermion metals represent a prototype system in this context, and have in particular provided the setting to study local quantum criticality that involves not only order-parameter fluctuations but also a Kondo breakdown [1]. Surprisingly, recent theoretical and experimental developments have revealed some unusual phases proximate to the heavy-fermion quantum critical points, thereby opening up an entirely new frontier on the relationship between quantum criticality and novel phases [1]. I will summarize the relevant recent experiments [2] and discuss them within the framework of a global phase diagram that was put forward several years ago [3] and has recently been discussed more extensively [4,5]. Our theoretical studies emphasize the interplay between two effects. One is the Kondo screening and its breakdown, and the other is the fluctuations in the quantum magnetism of local moments alone. The insights gained from these studies of the well-defined quantum criticality in heavy fermions may have broader relevance. Such implications will be discussed, in particular on the interplay between metallic antiferromagnetism, electronic localization and unconventional superconductivity. [4pt] [1] Q. Si and F. Steglich, Science 329, 1161 (2010).[0pt] [2] S. Friedemann et al., Nature Phys. 5, 465 (2009);[0pt] J. Custers et al., PRL 104, 186402 (2010).[0pt] [3] Q. Si, Physica B 378, 23 (2006); S. J. Yamamoto and Q. Si, PRL 99, 016401 (2007).[0pt] [4] Q. Si, Phys. Status Solidi B247, 631 (2010); S. J. Yamamoto and Q. Si, J. Low Temp. Phys. 161, 233 (2010).[0pt] [5] P. Coleman and A. H. Nevidomskyy, J. Low Temp. Phys. 161, 182 (2010).

Si, Qimiao

2011-03-01