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1

PHYTOEXTRACTION OF HEAVY METALS  

E-print Network

18/11/08 1 PHYTOEXTRACTION OF HEAVY METALS Stephanie Marshall Phytoextraction Hyperaccumulator of phytoextraction as a means for removing heavy metals from contaminated soils The use of plants to remove) Chelating Agents: desorb heavy metals from soil matrix and form water-soluble metal complexes (Shen et al

Blouin-Demers, Gabriel

2

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

3

Mutagenicity of heavy metals  

SciTech Connect

Certain heavy metals are required, as trace elements for normal cellular functions. However, heavy metals are toxic to cells once their levels exceed their low physiological values. The toxicity of heavy metals on microorganisms, and on animals has been well-documented. These interactions may induce the alteration of the primary as well as secondary structures of the DNA and result in mutation(s). The present communication reports the results in determining the mutagenicity and carcinogenicity of ten heavy metals commonly found in polluted areas by using the Salmonella/mammalian-microsome mutagenicity test.

Wong, P.K.

1988-04-01

4

Phytochelatins and heavy metal tolerance  

Microsoft Academic Search

The induction and heavy metal binding properties of phytochelatins in heavy metal tolerant (Silene vulgaris) and sensitive (tomato) cell cultures, in water cultures of these plants and in Silene vulgaris grown on a medieval copper mining dump were investigated. Application of heavy metals to cell suspension cultures and whole plants of Silene vulgaris and tomato induces the formation of heavy

I Leopold; D Günther; J Schmidt; D Neumann

1999-01-01

5

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

6

Heavy Metal Separator Funnel  

USGS Multimedia Gallery

This apparatus is known by various names: Separatory Funnel, Heavy Metal Separator, Sep Funnel and a few more. This is an example of antique lab equipment which can be found in the U.S. Geological Survey museum collection. Object ID: USGS-000239...

2009-07-22

7

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

8

Biosorption of heavy metals.  

PubMed

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-binding 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. Elucidation of mechanisms active in metal biosorption is essential for successful exploitation of the phenomenon and for regeneration of biosorbent materials in multiple reuse cycles. The complex nature of biosorbent materials makes this task particularly challenging. Discussion focuses on the composition of marine algae polysaccharide structures, which seem instrumental in metal uptake and binding. The state of the art in the field of biosorption is reviewed in this article, with many references to recent reviews and key individual contributions. PMID:7619394

Volesky, B; Holan, Z R

1995-01-01

9

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

10

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...

11

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

12

Heavy metal stabilization in municipal solid waste incineration flyash using heavy metal chelating agents  

Microsoft Academic Search

Heavy metal chemical stabilization with synthesized heavy metal chelating agent was assessed for flyash from municipal solid waste incinerator. Flyash can contain heavy metals (e.g. Pb, Cd) which can leach. A new kind of heavy metal chelating agent showed more attractive competition than inorganic chemicals in stabilizing flyash. The synthesizing method of this kind of heavy metal chelating agent was

Jiang Jianguo; Wang Jun; Xu Xin; Wang Wei; Deng Zhou; Zhang Yan

2004-01-01

13

The remediation of heavy metals contaminated sediment  

Microsoft Academic Search

Heavy metal contamination has become a worldwide problem through disturbing the normal functions of rivers and lakes. Sediment, as the largest storage and resources of heavy metal, plays a rather important role in metal transformations. This paper provides a review on the geochemical forms, affecting factors and remediation technologies of heavy metal in sediment. The in situ remediation of sediment

Jian-feng Peng; Yong-hui Song; Peng Yuan; Xiao-yu Cui; Guang-lei Qiu

2009-01-01

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

Heavy metals in Antarctic organisms  

Microsoft Academic Search

To evaluate levels of essential (zinc and copper) and non-essential (mercury and cadmium) heavy metals, 34 species of organisms\\u000a from different areas close to the Antarctic Peninsula were analysed. These included algae, filter-feeders, omnivorous invertebrates\\u000a and vertebrates. Mercury was not detected, while cadmium was found in the majority of organisms analysed (detection limit\\u000a was 0.05?ppm for both metals). The highest

J. E. A. de Moreno; M. S. Gerpe; V. J. Moreno; C. Vodopivez

1997-01-01

16

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

17

Heavy Metal Uptake by Rape  

Microsoft Academic Search

In pot experiments, the effect of single and combined pollution of soil by lead (Pb), cadmium (Cd), and zinc (Zn) and uptake of heavy metals in Brassica napus L. were investigated. There were two main factors that affected the assimilation of Pb, Cd, and Zn by rape: (i) level of soil pollution by the particular element and (ii) the combined

Violina Angelova; Radka Ivanova; Givko Todorov; Krasimir Ivanov

2008-01-01

18

Heavy metals extraction by microemulsions.  

PubMed

The objective of this study is the heavy metal extraction by microemulsion, using regional vegetable oils as surfactants. Firstly, the main parameters, which have influence in the microemulsion region, such as: nature of cosurfactant, influence of cosurfactant (C)/surfactant (S) ratio and salinity were studied, with the objective of choosing the best extraction system. The extraction/reextraction process by microemulsion consists of two stages. In the first one, the heavy metal ion present in the aqueous phase is extracted by the microemulsion. In a second step, the reextraction process occurs: the microemulsion phase, rich in metal, is acidified and the metal is recovered in a new aqueous phase, with higher concentration. The used system had the following parameters: surfactant-saponified coconut oil; cosurfactant-n-butanol; oil phase-kerosene; C/S ratio=4; salinity-2% (NaCl); temperature of 27+/-1 degrees C; water phase-aqueous solution that varied according to the heavy metal in study (Cr, Cu, Fe, Mn, Ni and Pb). A methodology of experimental planning was used (Scheffé Net) to study the behavior of the extraction in a chosen domain. The extraction was accomplished in one step and yielded extraction percentage higher than 98% for all metals. In the reextraction HCl-8M was used as reextraction agent and the influence of the pH and time were verified. This work showed the great efficiency of the microemulsion, indicating that it is possible to extract selectively the heavy metals from the aqueous phase. PMID:12753848

Dantas, T N Castro; Dantas Neto, A A; Moura, M C P A; Barros Neto, E L; Forte, K R; Leite, R H L

2003-06-01

19

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

20

Heavy metal fates in laboratory bioretention systems  

Microsoft Academic Search

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

Xueli Sun; Allen P. Davis

2007-01-01

21

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

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

Estimation of heavy metals in drinking water and development of heavy metal pollution index  

Microsoft Academic Search

Four heavy metals (Copper, Cadmium, Lead and Zinc) are monitored in drinking water at twelve important residential areas using DPASV Technique. The results indicate the water to free of heavy metal pollution. The data monitored have been used to compute Heavy metal pollution index (HPI) using weighted arithmetic mean method and the proposed Pollution Index (HPI) seems to be applicable

S. Venkata Mohan; P. Nithila; S. Jayarama Reddy

1996-01-01

24

FINAL REPORT. HEAVY METAL PUMPS IN PLANTS  

EPA Science Inventory

The long term goal of the funded research is to understand how heavy metals are taken up from the soil and translocated throughout the plant. The potential application of this research is to create plants with better heavy metal uptake systems and thereby improve the ability of t...

25

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

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

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

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 ions removal by chelating resin  

Microsoft Academic Search

Purpose – Preparation of chelating resin to be used in the removal of heavy metal ions from solutions. Design\\/methodology\\/approach – Chelating resin based on poly (glycidyl-methacrylate-co-N, N-methylene-bis-acrylamide) containing ethylenediamine was synthesised and used in removal of heavy metals from solutions. Findings – The optimal pH values for adsorption of different metal ions occur in the range 4.0-10.0 depending on the

N. M. Abd El-Moniem; M. R. El-Sourougy; D. A. F. Shaaban

2005-01-01

30

Chemistry 330 / Study Guide 217 Toxic Heavy Metals  

E-print Network

Chemistry 330 / Study Guide 217 Unit 7 Toxic Heavy Metals Overview In ancient Rome wine was stored. Metals--especially heavy metals--pose a unique environmental pollution problem. Heavy metals After completing this section, you should be able to 1. explain the difference between a heavy metal

Short, Daniel

31

Heavy metals--geochemical bogey men?  

PubMed

Heavy metals is a loose term usually used to indicate environmentally "bad" metals. It is poorly defined with a multitude of often contradictory definitions based on density, atomic weight, atomic number or other properties of the elements or their compounds. Alternative, scientifically rigorous definitions exist for subgroups of metals and should be used instead. PMID:15016455

Hodson, Mark E

2004-06-01

32

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

33

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. ...

34

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

35

Simultaneous removal of nitrate and heavy metals by iron metal*  

PubMed Central

Great attention should be paid now to simultaneously removing common pollutants, especially inorganic pollutants such as nitrate and heavy metals, as individual removal has been investigated extensively. Removing common pollutants simultaneously by iron metal is a very effective alternative method. Near neutral pH, heavy metals, such as copper and nickel, can be removed rapidly by iron metal, while nitrate removal very much slower than that of copper and nickel, and copper can accelerate nitrate removal when both are removed simultaneously. Even a little amount of copper can enhance nitrate removal efficiently. Different mechanisms of these contaminants removal by iron metal were also discussed. PMID:15822139

Hao, Zhi-wei; Xu, Xin-hua; Jin, Jian; He, Ping; Liu, Yong; Wang, Da-hui

2005-01-01

36

Heavy metal pollution in sediments of the Pasvik River drainage  

Microsoft Academic Search

The purpose of this paper is to study the regional impacts of heavy metals (Ni, Cu, Co, Zn, Cd, Pb, Hg) on the watershed of the Pasvik River. On the basis of sediment investigations at 27 stations of the watershed, background concentrations of the heavy metals, vertical distribution of heavy metals in sediments, heavy metal concentrations in surface sediments, contamination

Vladimir Dauvalter; Sigurd Rognerud

2001-01-01

37

Heavy Metal Tolerance Robert S. Boyd, Nishanta Rajakaruna  

E-print Network

Heavy Metal Tolerance Robert S. Boyd, Nishanta Rajakaruna Introduction The operation of biological processes (creating stress). Some heavy metals have important physiological roles, but high doses of these essential heavy metals or exposure to other heavy metals that lack physiological roles in organisms may

Rajakaruna, Nishanta

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

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

40

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

41

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

42

Design consideration for tungsten heavy metal  

SciTech Connect

Tungsten was rarely known to industry before 1909 when it was utilized as electric wire filament in the incandescent lamp. Up to 1927, tungsten was mainly employed in the manufacture of tool steels. In 1935, the first tungsten heavy metal pseudoalloys were produced by utilizing the powder metallurgy process of liquid-phase sintering. Tungsten is now the most economical material available for applications requiring the use of a high-density material. Some of the applications of tungsten heavy metal are related to aircraft counter-weights and missile ballast. A large increase in the tungsten provided by Canada and additional output from Mexico will make North America self-sufficient with respect to its needs for tungsten starting in 1985. Attention is given to heavy metal metallurgy, tungsten heavy metal alloy systems, and physical properties. In connection with the design of objects consisting of tungsten heavy metal, aspects of linear shrinkage have to be considered along with material density variations, and the maximum material condition concept.

Maurer, W.E.

1982-01-01

43

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

44

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

45

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

46

Heavy metals: sources and environmental presence.  

PubMed

The Istituto Superiore di Sanità has for many years been involved in the problem of environmental pollution caused by heavy metals. A brief review of the sources of this pollution is first presented which also includes the presence in nature of some heavy metals which are among the most dangerous. Data gathered by the authors is then presented from sampling of the emissions of urban solid waste (USW) incinerators and from environmental monitoring programs in different areas in Italy according to four categories: urban, industrial, rural and mixed. PMID:2624362

Ziemacki, G; Viviano, G; Merli, F

1989-01-01

47

Quantum criticality in heavy-fermion metals  

Microsoft Academic Search

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, that use these magnetic systems to address problems that are central to the broad understanding of strongly correlated quantum matter.

Philipp Gegenwart; Qimiao Si; Frank Steglich

2008-01-01

48

Partitioning of heavy metals in contaminated soils  

Microsoft Academic Search

Three soils and a sediment which had undergone massive prior additions of heavy metals were sequentially extracted so that Cd, Cu, Ni, and Zn could be partitioned into five operationally defined geochemical fractions: exchangeable, bound to carbonates, bound to Fe-Mn oxides, bound to organic matter, and residual. The highest amount of Cd (ca. 37%) was found in the exchangeable fraction,

Hickey

1982-01-01

49

Heavy metals content of canned tuna fish  

Microsoft Academic Search

In this study, five heavy metals in canned tuna fish were determined after digestion by the Association of Official Analytical Chemists methods. Mercury and arsenic levels in canned tuna fish were determined by hydride generation atomic absorption spectrophotometery while cadmium and lead levels were determined by graphite tube atomic absorption spectrophotometery and tin levels were determined by flame atomic absorption

F. Emami Khansari; M. Ghazi-Khansari; M. Abdollahi

2005-01-01

50

Acinetobacter bioreporter assessing heavy metals toxicity.  

PubMed

This work was conducted to employ a whole cell-based biosensor to monitor toxicity of heavy metals in water and wastewater. An isolate of industrial wastewater bacterium, Acinetobacter sp. DF4, was genetically modified with lux reporter gene to create a novel bioluminescent bacterial strain, designated as DF4/PUTK2. This bioreporter can investigate the toxicity through light inhibition due to cell death or metabolic burden and the specific stress effects of the tested soluble materials simultaneously. The use of Acinetobacter DF4/PUTK2 as a bioluminescent reporter for heavy metal toxicity testing and for the application of wastewater treatment influent toxicity screening is presented in this study. Among eight heavy metals tested, the bioluminescence of DF4/PUTK2 was most sensitive to Zn, Cd, Fe, Co, Cr followed by Cu in order of decreasing sensitivity. The same pattern of sensitivity was observed when several contaminated water and wastewater effluents were assayed. This work suggested that luxCDABE -marked Acinetobacter bacterium DF4/PUTK2 can be used to bioassay the ecotoxicity of wastewater and effluent samples contaminated with heavy metals. Using this assay, it is possible to pre-select the more toxic samples for further chemical analysis and to discard wastewater samples with low or no inhibition because they are not toxic to the environment. PMID:17009289

Abd-El-Haleem, Desouky; Zaki, Sahar; Abulhamd, Ashraf; Elbery, Hassan; Abu-Elreesh, Gadallah

2006-01-01

51

Heavy metal pollution in Wellington Harbour  

Microsoft Academic Search

Heavy metal analysis of the < 20 ?m fraction of marine sediments from Wellington Harbour and Waiwhetu Stream have shown that the Waiwhetu Stream is easily the most polluted area in the Wellington Harbour system with Pb and Zn in the extremely polluted category and Cu, Cd, and Hg in the moderately to strongly polluted category. These elements have different

P. Stoffers; G. P. Glasby; C. J. Wilson; K. R. Davis; P. Walter

1986-01-01

52

Heavy metal contamination in TIMS Branch sediments  

SciTech Connect

The objective of this memorandum is to summarize results of previous sediment studies on Tims Branch and Steed`s Pond conducted by Health Protection (HP) and by the Savannah River Laboratory (SRL) in conjunction with Reactor Materials Engineering & Technology (RMET). The results for other heavy metals, such as lead, nickel, copper, mercury, chromium, cadmium, zinc, and thorium are also summarized.

Pickett, J.B.

1990-06-25

53

Heavy metal contamination in TIMS Branch sediments  

SciTech Connect

The objective of this memorandum is to summarize results of previous sediment studies on Tims Branch and Steed's Pond conducted by Health Protection (HP) and by the Savannah River Laboratory (SRL) in conjunction with Reactor Materials Engineering Technology (RMET). The results for other heavy metals, such as lead, nickel, copper, mercury, chromium, cadmium, zinc, and thorium are also summarized.

Pickett, J.B.

1990-06-25

54

Heavy metals in MSW incineration fly ashes  

Microsoft Academic Search

Incineration is a common solution for dealing with the increasing amount of municipal solid waste (MSW). During the process, the heavy metals initially present in the waste go through several transformations, ending up in combustion products, such as fly ash. This article deals with some issues related to the combustion of MSW and the formation of fly ash, especially in

C. Ferreira; A. Ribeiro; L. Ottosen

2003-01-01

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 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

57

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

58

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

59

Heavy metal research in lacustrine sediment: a review  

Microsoft Academic Search

Heavy metals are released into environment from a wide range of natural and anthropogenic sources. Aquatic ecosystems are\\u000a normally at the receiving end and in many cases, with lakes as intermediaries. Lacustrine sediments are important sinks for\\u000a heavy metals and play a significant role in enrichment and remobilization of heavy metals in aquatic systems. Therefore, characteristics\\u000a of heavy metal in

Zhigang Yao; Pu Gao

2007-01-01

60

Minor heavy metal: A review on occupational and environmental intoxication  

PubMed Central

Heavy metal is widely used in industries and presents as a problematic environmental pollution. Some heavy metals, especially lead and mercury, are well described for their occupational and environmental intoxication whereas the other minor heavy metals are less concerned. In this article, the author will present the details of occupational and environmental minor heavy metal intoxication. This review focuses mainly on aluminum, tin, copper, manganese, chromium, cadmium and nickel. PMID:20040969

Wiwanitkit, Viroj

2008-01-01

61

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

62

How composting affects heavy metal content  

SciTech Connect

This paper describes ways in which a properly conducted composting process can alter the chemical forms of heavy metals and consequently the quality of the compost. This process is of particular interest in the Italian policy of waste management due to the low level of organic matter in Italian agricultural soils. Results of the studies show that the proper process of compost maturation seems to increase the concentrations of humic acids with respect to those of fulvic acids. These variations in the quantity and quality of humic substances influence the speciation of heavy metals with a large part of the metals complexed and reaching the soil in a less mobile form. The distribution of copper, cadmium, zinc, nickel, lead and chromium among humic fractions is compared in two composting procedures.

Canarutto, S.; Petruzzelli, G.; Lubrano, L.; Guidi, G.V.

1991-06-01

63

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

64

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

65

Contribution of Sulfonate Groups and Alginate to Heavy Metal  

E-print Network

Contribution of Sulfonate Groups and Alginate to Heavy Metal Biosorption by the Dry Biomass of heavy metal complexation by the dry biomass of the brown seaweed Sargassum fluitans was investigated. However, sulfonate groups can also contribute, to a lower extent, to heavy metal binding, particularly

Volesky, Bohumil

66

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

67

Tons of Heavy Metals in Mill Creek Sediments Heather Freeman  

E-print Network

Tons 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 Heavy metals may accumulate in the sediment of rivers or creeks. Precipitation results in urban runoff

Maynard, J. Barry

68

THERMODYNAMIC STUDY OF HEAVY METALS BEHAVIOUR DURING MUNICIPAL WASTE INCINERATION  

E-print Network

THERMODYNAMIC STUDY OF HEAVY METALS BEHAVIOUR DURING MUNICIPAL WASTE INCINERATION Y. ME´ NARD, A significantly to the presence of heavy metals in urban area aerosols. It is thus important to ascertain the quantities and chemical forms of the heavy metals (HM) that are emitted from the incineration plant stacks

Boyer, Edmond

69

A Fuzzy Model of Heavy Metal Loadings in Marine Environment  

E-print Network

A Fuzzy Model of Heavy Metal Loadings in Marine Environment L.I. Kuncheva1 , J. Wrench2 , L.C. Jain model of the loadings of heavy metals for two coastal areas of the Irish Sea (Liverpool Bay, Morecambe Bay, heavy metal concentrations, index of spa- tial distribution, spatial data analysis. 1

Kuncheva, Ludmila I.

70

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.

71

Enhanced Bioaccumulation of Heavy Metals by Bacterial Cells Displaying  

E-print Network

Enhanced Bioaccumulation of Heavy Metals by Bacterial Cells Displaying Synthetic Phytochelatins strategy for develop- ing high-affinity bioadsorbents suitable for heavy metal removal. © 2000 John Wiley & Sons, Inc. Biotechnol Bioeng 70: 518­524, 2000. Keywords: heavy metals; bioadsorbents; Lpp

Chen, Wilfred

72

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

73

Permeable Reactive Biobarriers for the Containment of Heavy Metal  

E-print Network

Permeable 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. Heavy metals are leached as ground water reaches the exposed ores. Arizona has a rich history

Fay, Noah

74

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 of heavy metals in these bays. Samples were collected from four different environments in the selected bays detection limits (BDL). This study shows concentrations of heavy metals in the selected bays were present

Gilbes, Fernando

75

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

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

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

78

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

79

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

80

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

81

Heavy Metal Removal in Cold Climate Bioretention  

Microsoft Academic Search

A bioretention media is a stormwater treatment option designed to reduce peak runoff volumes and improve water quality through\\u000a soil infiltration and plant mitigation. To investigate the heavy metal removal in a bioretention media in a cold climate setting,\\u000a a small pilot sized bioretention box was built in Trondheim, Norway. The system was sized using the Prince Georges County\\u000a bioretention

Tone M. Muthanna; Maria Viklander; Nina Gjesdahl; Sveinn T. Thorolfsson

2007-01-01

82

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

83

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

84

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

85

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

86

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

87

Efflux-mediated heavy metal resistance in prokaryotes.  

PubMed

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 that of the heavy metal resistant bacterium Ralstonia metallidurans. This comparison shows that heavy metal resistance is the result of multiple layers of resistance systems with overlapping substrate specificities, but unique functions. Some of these systems are widespread and serve in the basic defense of the cell against superfluous heavy metals, but some are highly specialized and occur only in a few bacteria. Possession of the latter systems makes a bacterium heavy metal resistant. PMID:12829273

Nies, Dietrich H

2003-06-01

88

Contamination of environment with heavy metals emitted from automotives  

SciTech Connect

Interest has arisen in heavy-metal contamination of the environment, mostly because of potential hazards to the health of animals and human (directly and/or indirectly). High levels of heavy metals in soil, plants, and the atmosphere are often related to industries, highways, chemical dumping, impure chemical fertilizers, and pesticides containing metals. An important source of heavy metals, especially lead, is from the combustion of leaded gasoline used for transportation. Other heavy metals associated with transportation include nickel, which is also added to gasoline and is contained in engine parts, zinc, and cadmium from tires, lubricating oils, and galvanized parts such as fuel tanks.

Falahi-Ardakani, A.

1984-04-01

89

Genetic engineering strategies for enhancing phytoremediation of heavy metals  

Microsoft Academic Search

The industrial revolution has increased the use of metals for various processes and operations. The waste containing heavy metals are transported to the environment; air, water and soil through the various sources which has increased the burden in the environment. Phytoremediation has been found a promising, cost-effective, aesthetically pleasing, in situ treatment technology for the remediation of heavy metal contaminants

M. H. Fulekar; Anamika Singh; Anwesha M. Bhaduri

2009-01-01

90

Heavy metals in MSW incineration fly ashes  

NASA Astrophysics Data System (ADS)

Incineration is a common solution for dealing with the increasing amount of municipal solid waste (MSW). During the process, the heavy metals initially present in the waste go through several transformations, ending up in combustion products, such as fly ash. This article deals with some issues related to the combustion of MSW and the formation of fly ash, especially in what concerns heavy metals. Treatment of the flue gas in air pollution control equipment plays an important role and the basic processes to accomplish this are explained. Fly ash from a semi-dry flue gas treatment system is characterized regarding its physical-chemical properties: pH, solubility, chemical composition, and leaching, amongst others. Results indicate a high alkalinity and the presence of large amounts of calcium, chlorides, sulfates, carbonates, sodium and potassium. Metal concentrations in fly ash are: 6,2g/kg for zinc, 2,4g/kg for lead, 1,7g/kg for iron, and 7,9g/kg for magnesium. Copper, manganese, chromium and cadmium are also present with 546, 338, 104 and 91mg/kg of fly ash, respectively. These results are extremely important in subsequent studies on the treatment of fly ash.

Ferreira, C.; Ribeiro, A.; Ottosen, L.

2003-05-01

91

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

92

Perspective on Phytoremediation for Improving Heavy Metal-Contaminated Soils  

Microsoft Academic Search

\\u000a Heavy metal pollution of soil is a significant environmental problem and has its negative potential impact on human health\\u000a and agriculture. Phytoremediation strategies with appropriate heavy metal-adapted rhizobacteria (for example, mycorrhizae)\\u000a have received more and more attention. Some plants possess a range of potential mechanisms that may be involved in the detoxification\\u000a of heavy metals, and they manage to survive

Hong-Bo Shao; Li-Ye Chu; Fu-Tai Ni; Dong-Gang Guo; Hua Li; Wei-Xiang Li

93

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

94

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

95

Fluorescent ion indicators for detecting heavy metals  

NASA Astrophysics Data System (ADS)

A series of fluorescent ion indicators were tested for their spectral response to submicromolar levels of 13 divalent and trivalent metal ions in aqueous solution. Upon binding their target ions, these fluorescent compounds exhibit changes in fluorescence emission intensity that are easily detectable, making them useful for direct the detection of soluble heavy metal ions including Hg2+, Cu2+, Ni2+ and Cd2+. The fluorescence response of these indicators to ion binding results from photoinduced electron transfer effects, fluorophore/quencher interactions, fluorescence quenching by heavy metal ions or a combination of these processes. The majority of the indicators we tested bind their target ions reversibly with dissociation constants (Kd) near 1 (mu) M (approximately 1 ppm) and detection limits near 100 nM (approximately 100 ppb) at pH 7. However, several indicators exhibit very high affinity for their target ion; for example, Magnesium GreenTM binds Zn2+ with a Kd near 20 nM. All the indicators synthesized and tested are based on water-soluble fluorophores that have high fluorescence quantum yields (from 0.3 to 0.7) and can be excited with an Ar laser, fluorometer or hand- held UV lamp. Furthermore, the excitation and emission spectra of these indicators are insensitive to pH changes over the range of 5 to 10, as well as to high concentrations of K+, Na+, Ca2+ and Mg2+. These properties make the indicators useful for the direct measurement of metal ions in solutions, such as biological fluids, sea water and waste streams, that contain high concentrations of salts.

Kuhn, Michael A.; Hoyland, Brian; Carter, Scott; Zhang, Cailan; Haugland, Richard P.

1995-05-01

96

MELIMEX, an experimental heavy metal pollution study: Oligochaetes and chironomid larvae in heavy metal loaded and control limno-corrals  

Microsoft Academic Search

In two limno-corrals loaded with heavy metals the density of tubificid worms and chironomid larvae was higher than in the\\u000a control. The better oxygen conditions observed in the heavy metal loaded corrals might explain this discrepancy. The higher\\u000a oxygen concentration at the sediment-water interface was due to lower organic sedimentation, consequence of the primary production\\u000a reduced by heavy metals. In

Claude Lang; Barbara Lang-Dobler

1979-01-01

97

SULFIDE PRECIPITATION OF HEAVY METALS: EFFECT OF COMPLEXING AGENTS  

EPA Science Inventory

Process wastewaters containing heavy metals result from metal finishing and production operations and certain inorganic chemical manufacturing operations. Depending on their origin, these process wastewaters may also contain chelating agents such as EDTA, citrate, etc. The effect...

98

Strategies of heavy metal uptake by three plant species growing near a metal smelter  

Microsoft Academic Search

Some higher plant species have developed heavy metal tolerance strategies which enable them to survive and reproduce in highly metal-contaminated soils. We have investigated such heavy metal uptake and accumulation strategies of two absolute metallophyte species (Armeria maritima ssp. halleri and Cardaminopsis halleri) and one pseudometallophyte (Agrostis tenuis) growing near a former metal smelter. Samples of plant parts and soil

H Dahmani-Muller; F van Oort; B Gélie; M Balabane

2000-01-01

99

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

100

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

101

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

102

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...

103

Heavy metals in edible seaweeds commercialised for human consumption  

Microsoft Academic Search

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

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

2009-01-01

104

Bioremediation of heavy metals using biostimulation in laboratory bioreactor.  

PubMed

The present research study investigates bioremediation potential of biostimulated microbial culture isolated from heavy metals waste disposal contaminated site located at Bhayander (east), Mumbai, India. The physicochemical and microbial characterization including heavy metal contaminants have been studied at waste disposal site. The microorganisms adapted at heavy metal-contaminated environment were isolated, cultured, and biostimulated in minimal salt medium under aerobic conditions in a designed and developed laboratory bioreactor. Heavy metals such as Fe, Cu, and Cd at a selected concentration of 25, 50, and 100 ?g/ml were taken in bioreactor wherein biostimulated microbial culture was added for bioremediation of heavy metals under aerobic conditions. The remediation of heavy metals was studied at an interval of 24 h for a period of 21 days. The biostimulated microbial consortium has been found effective for remediation of Cd, Cu, and Fe at higher concentration, i.e., 100 mg/l up to 98.5%, 99.6%, and 100%, respectively. Fe being a micronutrient was remediated completely compared to Cu and Cd. During the bioaccumulation of heavy metals by microorganisms, environmental parameters such as pH, total alkalinity, electronic conductivity, biological oxygen demand, chemical oxygen demand, etc. were monitored and assessed. The pilot scale study would be applicable to remediate heavy metals from waste disposal contaminated site to clean up the environment. PMID:22270588

Fulekar, M H; Sharma, Jaya; Tendulkar, Akalpita

2012-12-01

105

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 ...

106

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

107

Heavy metal pollution in Tianjin Bohai Bay, China  

Microsoft Academic Search

The contamination levels and distribution characters of heavy metals in coastal waters and sediments from Tianjin Bohai Bay, China were examined. Pb and Zn were found as the main heavy metal pollutants in the coastal waters of the bay. High levels of Pb and Zn appeared especially near the estuary, indicating that river discharge was the main pollution source. Moreover,

Wei MENG; Yanwen QIN; Binghui ZHENG; Lei ZHANG

2008-01-01

108

Soil Pollution by Heavy Metals and Remediation (Mazandaran-Iran)  

Microsoft Academic Search

Heavy metals and metalloids are an increasing environmental problem worldwide. Some industrial activities and agricultural practices increase their level in the substrate and the possible introduction of these elements in the food chain is an increasing human health concern. The protection and restoration of soils and water contaminated with heavy metals generate a great need to develop efficient adsorbents for

M. R. Kalantari; M. Shokrzadeh; A. G. Ebadi; C. Mohammadizadeh; M. I. Choudhary; Atta-Ur-Rahman

2006-01-01

109

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...

110

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

111

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

112

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

113

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

114

Plant productivity and heavy metal contamination  

SciTech Connect

This article describes the potential for use of composts from green waste and from municipal solid wastes for agricultural use in Italy. The accumulation of heavy metals in compost-amended soils and crops was evaluated and the influence of these composts on plant productivity was studied. Green compost was obtained from vegetable organic residues; municipal solid waste derived compost was obtained from the aerobic biostabilization of a mixture of the organic biodegradable fraction of municipal solid waste and sewage sludge. The two composts had good chemical characteristics and their use caused no pollution to soil and plants. The overall fertilizing effect was higher for green compost even though green compost and municipal solid waste derived compost had similar contents of primary elements of fertility.

Guidi, G.V.; Petruzzelli, G.; Vallini, G.; Pera, A.

1990-06-01

115

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

116

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

117

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

118

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

119

MELIMEX, an experimental heavy metal pollution study: Effects of increased heavy metal load on crustacea plankton  

Microsoft Academic Search

The crustacea plankton of three artificial model lakes in Lake Baldegg was observed during 15 months. Two were loaded continuously\\u000a with low concentrations of five heavy metals (Hg, Cu, Cd, Zn, Pb).\\u000a \\u000a It was attempted to explain the significant lower abundances of the loaded limno-corrals. The results suggest that the decrease\\u000a was not, or only partially, caused by the lower

Jacques Urech

1979-01-01

120

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

121

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

122

Content of heavy metals in the hair  

NASA Astrophysics Data System (ADS)

The aim of our investigation was to determine of HM content in the hair of people and animals. Two of the main essential elements-Zn and Cu and two of the supertoxical heavy metals- Pb and Cd were chosen. The investigations were conducted in Russian Federation and Belarus Republic in 2001-2002. About 500 hair samples of people, dogs, cats, cattle, horses, yaks, pigs, sheep goats and rabbits were studied by the stripping voltammetric analysis (SVA) method with TA- 2 analyzer to determine Zn, Cu, Pb and Cd concentrations. The hair samples were prepared according to the methods developed in Tomsk University (Russia) and improved by the authors. The essence of the methods is the multiconsecutive burning of hair samples to ashes and boiling them in concentrated acids to dissolve chemical combinations and transform their metals into ion forms. The zinc concentration was the highest in all hair samples (58.65 ... 195.15 mg/kg). The copper content was several times less (5.49 ... 22.63 mg/kg). Lead and cadmium were detected in relatively low amounts (0.32 ... 2.42 mg/kg and 0.04 ... 0.92 mg/kg respectively). The highest Pb and Cd levels were detected in cats and people hair.

Patrashkov, S. A.; Petukhov, V. L.; Korotkevich, O. S.; Petukhov, I. V.

2003-05-01

123

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

124

Heavy metal exposure from personal care products.  

PubMed

Numerous studies have described human exposure to heavy metals from diverse sources in Nigeria, but little is known about the exposure from personal care products, and few or no report is available on the personal care product concentrations of cadmium, chromium, copper and zinc, which have biotic effects. The levels of these elements were determined in 74 samples of 5 different classes of personal care products commonly used in Nigeria using atomic absorption spectrophotometry. Significant levels of Cd, Cr, Cu and Zn were found in all the products. The highest values of Cd (0.553 ppm) and Cu (0.783 ppm) were observed in hair cream, while medicated cream was mostly implicated for Cr (0.383 ppm) and Zn (0.793 ppm). Since no limit relating to cosmetic products is available, it is difficult to ascertain if the values of metals obtained in this study are too high or low; but Cd and Cr are prohibited in any amount in cosmetics. Prolonged use of soaps and creams containing these elements may pose threat to human health and the environment. PMID:19789830

Ayenimo, J G; Yusuf, A M; Adekunle, A S; Makinde, O W

2010-01-01

125

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

126

Heavy metals in the hydrological cycle: Trends and explanation  

NASA Astrophysics Data System (ADS)

This paper reviews the major sources and transport characteristics of heavy metals in the hydrological cycle. It is demonstrated that heavy metal releases to the environment have changed from 19th and early 20th century production-related activities to consumption-oriented factors in more recent times. The relative roles of particle size, sorption and desorption processes, partitioning and the chemical speciation of heavy metals on fine sediments are identified to understand the likely fate of heavy metals released into fluvial systems. It is argued that the spatial and temporal distribution of heavy metals in the river corridor depends not only on an understanding of metal solubility and speciation, but also on an understanding of sediment dynamics which control, for example, floodplain alluviation and the accumulation of metals in the bottom sediments of contaminated rivers, lakes and reservoirs. Existing long- and short-term records are examined to identify the current state of knowledge about the factors which affect heavy metal releases into aquatic environments. With limited exceptions, it is shown that few long-term studies of trends in heavy metal transport are available although, for some major rivers, limited data on trends in metal concentration exists. Palaeolimnological reconstruction techniques, based on an analysis of lake and reservoir sediments, are identified as a possible means of supplementing monitored records of heavy metal transport. Although numerous studies have suggested that trends in atmospheric contamination, mining and urbanization may be identified in the bottom sediment record, other research has shown that the radionuclide-based chronology and the heavy metal distribution within the sediment are more likely to be a function of post-depositional remobilization than the history of metal loading to the basin. Despite these limitations, it is shown that the incorporation of reservoir bottom sediment analysis into a heavy metal research programme, based in river corridors of Midland England, provides an opportunity to identify and quantify the relative contribution of point and non-point contributions to the heavy metal budget and to relate trends in metal contamination to specific periods of catchment disturbance.

Foster, I. D. L.; Charlesworth, S. M.

1996-02-01

127

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

128

Heavy metals in sediment cores from a NW Spain estuary  

SciTech Connect

Core samples have been used to describe the chronology of heavy metal inputs to aquatic systems. Metal concentration profiles have been investigated to detect pollution, to establish when the polluting event started, and to quantify its magnitude relative to [open quotes]precivilization[close quotes] background values. Less frequently, and mainly in studies of coastal systems, the heavy metal nonresidual fraction has been measured to estimate the portion of trace metals potentially available for the biota or remobilization processes, and to assist in identifying the origin of metal inputs. This work is part of a wider study of metal concentrations in organisms and superficial sediments from a small estuary in NW Spain. The aims of this research were to detect any potential pollutant input to the sediments of the estuary, and to establish the influence of postdepositional redistribution on the heavy metal concentrations of oxidized surface sediments. 17 refs., 1 fig.

Barreiro, R.; Real, C.; Carballeira, A. (Universidad de Santiago de Compostela (Spain))

1994-09-01

129

Selected aquatic plants as indicator species for heavy metal pollution  

Microsoft Academic Search

Heavy metal pollution of the aquatic environment is often responsible for depletion of fishery resources and sudden fish?kills. Some aquatic plants do selectively accumulate specific metals and can serve as biological monitors. Two vascular plants, Potamogeton and Equisetum and a blue algae Oscillatoria have proved useful for monitoring metal pollution.

S. Ray; W. White

1976-01-01

130

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

131

Heavy Metal Tolerance in Plants J.ANTONOVIOS  

E-print Network

#12;Heavy Metal Tolerance in Plants J.ANTONOVIOS Department of Biology. University of Stirling.K. I. Introduction . . . . . . . . . . . 2 I1. Ecology of Metal Tolerance . . . . . . . . . 4 A on Contaminated Soils . . 19 1. Metal Concentration and Type . . . . . . . 19 2. Other Soil Factors

Antonovics, Janis

132

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

133

Heavy Metals Stimulate Human LINE-1 Retrotransposition  

PubMed Central

L1 and Alu elements are among the most active retroposons (mobile elements) in the human genome. Several human diseases, including certain forms of breast cancer and leukemia, are associated with L1 and Alu insertions in functionally important areas of the genome. We present data demonstrating that environmental pollutants, such as heavy metals, can stimulate L1 retrotransposition in a tissue culture system using two different types of assays. The response to these agents was equivalent when using a cell line with a stably integrated L1 vector (genomic) or a by introducing the L1 vector by transient transfection (episomal) of the cell. Reproducible results showed that mercury (HgS), cadmium (CdS), and nickel (NiO) increase the activity of L1 by an average of three (3) fold p<0.001. This observation is the first to link several carcinogenic agents with the increased retrotransposition activity of L1 as an alternate mechanism of generating genomic instability contributing to the process of carcinogenesis. Our results demonstrate that mobile element activation must be considered as one of the mechanisms when evaluating genomic damage/instability in response to environmental agents. PMID:16705797

Kale, Shubha P.; Moore, Lakisha; Deininger, Prescott L.; Roy-Engel, Astrid M.

2005-01-01

134

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

135

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

136

Molecular mechanisms of heavy metal hyperaccumulation and phytoremediation.  

PubMed

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 cellular/molecular mechanisms of metal tolerance/hyperaccumulation by plants are reviewed. The major processes involved in hyperaccumulation of trace metals from the soil to the shoots by hyperaccumulators include: (a) bioactivation of metals in the rhizosphere through root-microbe interaction; (b) enhanced uptake by metal transporters in the plasma membranes; (c) detoxification of metals by distributing to the apoplasts like binding to cell walls and chelation of metals in the cytoplasm with various ligands, such as phytochelatins, metallothioneins, metal-binding proteins; (d) sequestration of metals into the vacuole by tonoplast-located transporters. The growing application of molecular-genetic technologies led to the well understanding of mechanisms of heavy metal tolerance/accumulation in plants, and subsequently many transgenic plants with increased resistance and uptake of heavy metals were developed for the purpose of phytoremediation. Once the rate-limiting steps for uptake, translocation, and detoxification of metals in hyperaccumulating plants are identified, more informed construction of transgenic plants would result in improved applicability of the phytoremediation technology. PMID:16028496

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

2005-01-01

137

NMR microscopy of heavy metal absorption in calcium alginate beads  

SciTech Connect

In recent years, heavy metal uptake by biopolymer gels, such as Cal-Alginate or chitosan, has been studied by various methods. This is of interest because such materials might be an alternative to synthetical ion-exchange resins in the treatment of industrial waste waters. Most of the work done in this field consisted of studies of equilibrium absorption of different heavy metal ions with dependence on various experimental parameters. In some publications, the kinetics of absorption were studied, too. However, no experiments on the spatial distribution of heavy metals during the absorption process are known to us. Using Cu as an example, it is demonstrated in this article that NMR microscopy is an appropriate tool for such studies. By the method presented here, it is possible to monitor the spatial distribution of heavy metal ions with a time resolution of about 5 min and a spatial resolution of 100 {mu}m or even better. 14 refs., 10 figs.

Nestle, N.; Kimmich, R. [Universitaet Ulm (Germany)

1996-01-01

138

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...

139

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

140

Use of Cladophora glomerata to monitor heavy metals in rivers  

Microsoft Academic Search

Methods were developed for the use ofCladophora glomerata to monitor heavy metal concentrations in flowing waters. At least under conditions without marked fluctuations in ambient\\u000a metal concentration, there was no detectable difference in the metal concentrations of young plants between terminal 2-cm\\u000a lengths of filament and whole plants. In order to establish the relationship between metal concentration in plant and

B. A. Whitton; I. G. Burrows; M. G. Kelly

1989-01-01

141

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

142

Heavy metal bioaccumulation and toxicity with special reference to microalgae  

Microsoft Academic Search

The bioaccumulation and toxicity of heavy metals were reviewed with special reference to microalgae, the key component of\\u000a the food web in aquatic ecosystems. Heavy metals enter algal cells either by means of active transport or by endocytosis through\\u000a chelating proteins and affect various physiological and biochemical processes of the algae. The toxicity primarily results\\u000a from their binding to the

K. K. I. U. Arunakumara; Xuecheng Zhang

2008-01-01

143

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

144

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

145

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

146

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

147

The Search for Novel Integron Expression Along a Heavy Metal Gradient , Anne Giblin2  

E-print Network

The Search for Novel Integron Expression Along a Heavy Metal Gradient Brian Suh1 , Anne Giblin2 in the form of heavy metals. Doing so would provide insight into the diversity of genes found in environmental inducing levels of heavy metals. As increased heavy metal concentrations should correlate with increased

Vallino, Joseph J.

148

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

149

Phytoremediation of heavy metals--concepts and applications.  

PubMed

The mobilization of heavy metals by man through extraction from ores and processing for different applications has led to the release of these elements into the environment. Since heavy metals are nonbiodegradable, they accumulate in the environment and subsequently contaminate the food chain. This contamination poses a risk to environmental and human health. Some heavy metals are carcinogenic, mutagenic, teratogenic and endocrine disruptors while others cause neurological and behavioral changes especially in children. Thus remediation of heavy metal pollution deserves due attention. Different physical and chemical methods used for this purpose suffer from serious limitations like high cost, intensive labor, alteration of soil properties and disturbance of soil native microflora. In contrast, phytoremediation is a better solution to the problem. Phytoremediation is the use of plants and associated soil microbes to reduce the concentrations or toxic effects of contaminants in the environments. It is a relatively recent technology and is perceived as cost-effective, efficient, novel, eco-friendly, and solar-driven technology with good public acceptance. Phytoremediation is an area of active current research. New efficient metal hyperaccumulators are being explored for applications in phytoremediation and phytomining. Molecular tools are being used to better understand the mechanisms of metal uptake, translocation, sequestration and tolerance in plants. This review article comprehensively discusses the background, concepts and future trends in phytoremediation of heavy metals. PMID:23466085

Ali, Hazrat; Khan, Ezzat; Sajad, Muhammad Anwar

2013-05-01

150

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

151

Determination of Heavy Metal Contents in Samples of Medicinal Herbs  

Microsoft Academic Search

The heavy metals Cd, Pb, Zn, Ni and Mo were determined in 27 samples of medicinal herbs taken from various places in Bielsko Biata and the neighbouring area. Samples were digested by the wet method in a microwave oven. Flame AAS and differential pulse polarography (anodic and stripping voltammetry) were used for determination of these metals. Oriental tobacco (CTA-ATL-1) as

I. Baranowska; K. Srogi; A. W?ochowicz; K. Szczepanik

152

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

153

The use of bird feathers for indicating heavy metal pollution  

Microsoft Academic Search

Feather material has been investigated as suitable indicating tissue for heavy metal pollution. At least three different routes are described through which trace metal content in the feathers can increase: internal deposition during growth, contamination by the bird's secretion and outside contamination.

A. A. Goede; M. DE BRUIN

1986-01-01

154

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

155

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

156

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...

157

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...

158

Heavy metal capture and accumulation in bioretention media.  

PubMed

Heavy metal capture and accumulation in bioretention media were investigated through the use of a one-dimensional filtration equation for particulate metals, advection/dispersion/adsorption transport equations for dissolved metals, and sequential extractions. Predicted spatial profiles and partitioning patterns of captured metals were compared to data derived from a bioretention cell in the District of Columbia. Zinc, lead, and copper profiles showed a high surface accumulation, significantly decreasing with the media depth. Surface street particle-enriched areas had the highest heavy metal levels, demonstrating a close relationship between capture of metals and runoff particles. Sequential extractions suggested that most captured metals were of anthropogenic origin. Soluble-exchangeable bound metals from the sequential extraction correlated well with predicted aqueous dissolved metals; the more strongly associated metal fractions correlated with modeled runoff and media particulate metals. A simple risk evaluation indicated thatlead isthe limiting metal in bioretention accumulation. On the basis of information collected in this study, a shallow bioretention cell design is suggested for systems with a focus on metal capture. PMID:18754376

Li, Houng; Davis, Allen P

2008-07-15

159

Physiological sensitivity of freshwater macroinvertebrates to heavy metals.  

PubMed

Macroinvertebrate species traits, such as physiological sensitivity, have successfully been introduced in trait-based bioassessment approaches and are important predictors of species sensitivity in the field. The authors ranked macroinvertebrate species according to their physiological sensitivity to heavy metals using toxicity data from acute laboratory assays. Rankings for each of the heavy metals, Cd, Cu, Cr, Ni, Pb, Zn, and Hg, were standardized based on all available species data. Rankings for different heavy metals on the species level showed no significant difference between compounds and were reasonably well correlated pairwise (0.50heavy metal ranking was developed, which assigns a single physiological sensitivity value (S(metal) ) to macroinvertebrate taxa. Considering the high variation, especially for higher taxonomic levels, that is, in the order level, it is recommended to use S values of the genus or species level for meaningful analyses. In terms of taxonomic ranking, crustaceans were overall the most sensitive taxonomic group, whereas insects were generally the most tolerant group. Species in the order of Cladocera were three orders of magnitude more sensitive than insects of the order of Trichoptera. By contrast, mollusks covered a wide range of sensitivities, with bivalves being on average one order of magnitude more sensitive than gastropods. The authors concluded that physiological sensitivity represents a promising trait for trait-based risk assessment that together with other demographic and recolonization traits may help to identify the effects of heavy metal pollution in aquatic ecosystems. PMID:22553143

Malaj, Egina; Grote, Matthias; Schäfer, Ralf B; Brack, Werner; von der Ohe, Peter Carsten

2012-08-01

160

Heavy Metals Contamination of Table Salt Consumed in Iran  

PubMed Central

Lead, cadmium, mercury and arsenic are the most important heavy metals which may cause health risks following consumption of contaminated foods. Table salt is one the mostly used food additive with unique place in food consumption. Although purified table salt is expected to have lower level of contamination, some Iranians still prefer to use rock salt. Use of rock salt for food purposes has been banned by Iranian health authorities. In this study, heavy metal contamination of table salt consumed in Iran has been investigated. One hundred samples of rock and refined table salts were analyzed using atomic absorption spectrophotometeric methods for the presence of toxic heavy metals. The mean concentration of tested tracer metals including Cd, Pb, Hg and As was 0.024, 0.438, 0.021 and 0.094 ?g/g, respectively. The concentrations of tested heavy metals were well below the maximum levels set by Codex. However, no statistically significant difference was found between contamination of rock salt and refined salt to heavy metals. PMID:24363718

Cheraghali, Abdol Majid; Kobarfard, Farzad; Faeizy, Noroldin

2010-01-01

161

Characterisation and distribution of heavy metals at Masaya volcano, Nicaragua  

NASA Astrophysics Data System (ADS)

Activity at Masaya volcano, Nicaragua, is characterised by periodic cycles of intense gas emission that last years to decades. The volcano entered its current phase of degassing in 1993, which resulted in a low-level persistent gas plume. As a result of this continuous emission, the substantial deposition of heavy metals onto the surrounding soils (andosols) is thought to be occurring (Delfosse et al., 2003). The deposition of these heavy metal plume components, and their incorporation into soil, is of key interest because once discharged to the environment they accumulate throughout the food chain and may pose a serious ecological threat (Alloway, 1995). Although many studies have focused on the impacts of volcanic gases on the environment, few have addressed the fate of the metals released by persistent gas plumes. This study therefore investigates the patterns of heavy metal transport, deposition and distribution at Masaya in order to provide additional information on the processes that govern the behaviour of volcanic heavy metals. A number of agricultural and non-agricultural soils at two horizons (A: 0-10 cm and B: 20-30 cm) were collected and their trace metal content analysed. Twenty sites were sampled from the active vent to ~5 km downwind, as well as two control sites upwind of the volcano. Preliminary data suggest that a rapid deposition of metals occurs close to the source, with metal concentrations in the soil generally decreasing with distance away from the active vent. Cr and As clearly follow this trend, with maximum concentrations of 20.71 and 7.61 mg/kg respectively occurring closest to the vent. Concentration peaks for Mn, Co, Ni, Cu, and Zn (959.30, 21.57, 13.44, 152.85, and 72.73 mg/kg respectively) occur slightly further away from the vent, implying that these metals are transported further. The concentration of Cr, Co, Al, Ni and Mn was found to increase from soil horizon A to B, whereas the abundance of Zn decreases with depth. Heavy metal concentrations in the soils from the control sites were generally lower than the sites downwind of the active vent, confirming that the plume is a contributing factor to the total metal content. Although the measured concentrations do not exceed soil guideline values, further studies are required in order to evaluate the impacts of the currently increasing gas emission at Masaya volcano on heavy metal accumulation in soils, and to determine the regions that are most at risk of reaching potentially toxic levels. Alloway (1995) Heavy Metals in Soils, Chapman and Hall, London Delfosse et al. (2003) AGU Fall Meeting, Abstract V21C-0525

Hinrichs, M.; Rymer, H.; Gillman, M.; Blake, S.

2011-12-01

162

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

163

Heavy metals in composts of separated municipal wastes  

SciTech Connect

This study is to examine the influence of the metal components on the contents of heavy metals in composts of Municipal Solid Wastes (MSW). Fresh MSW used in composting was obtained from the city landfill of Taichung in Taiwan. Compost 1 was from as-collected MSW; Compost 2 was from degradable fraction in MSW; Compost 3 was from MSW without metal. The results show that the total concentration of zinc is the highest among the five heavy metals examined. Paper wastes are main sources of lead and copper with average concentrations of 18.53 mg/kg and 26.92 mg/kg of compost on dry weight. The contents of nickel and cadmium are relatively low. The total concentrations of the five heavy metals in composts increase by typical ratios between 1.72 and 2.58 for Composts 2 and 3, but 3.16 to 4.69 for Compost 1. The increase of concentration around a ratio of 2.0 is due to the loss of degraded organic matter. For the ratios above 2.0, fractions of some heavy metals have corroded from the surfaces of metal components into the Compost 1 in the early phase of acidic fermentation.

Liao, W.P.; Huang, W.C.; Fan, W.H. [Chung-Hsing Univ., Taichung (Taiwan, Province of China). Dept. of Environmental Engineering; Hsu, C.C. [Ging Phone Engineering Co., Taoyuan (Taiwan, Province of China)

1997-12-31

164

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

165

Research on the Heavy Metal Recovery using the Electrokinetic Phenomenon  

NASA Astrophysics Data System (ADS)

Recently, the pollution of the soil by heavy metal elution from industrial effluents and so on becomes serious with the development of the industry. Until now, many techniques such as diffusion prevention and elution prevention, extraction and removal, decomposition and decontamination have been proposed in the method of processing of polluted soil. In recent years, especially the method for using the electrokinetic phenomenon is noticed. In this method, the paired electrode is inserted in the soil, and the DC voltage is applied. Then, the electrokinetic phenomenon by the procedure of the superscription, namely electrophoresis, electroendosmose, electrolysis, is utilized. However, in the conventional research, recovery quantity of the heavy metal ion is low, and the improvement in the recovery efficiency is desired in order to use this technique for the repair of the polluted soil. Following fact is mentioned as the reason why the recovery efficiency of the heavy metal ion lowers. When the heavy metal ion has moved from the anode to the cathode, it combines with hydroxide ion made by the electrolysis of the water at the cathode, and it has precipitated as a hydroxide. The purpose of this study is prevention of the alkalinization by adding the acid at the proper quantity, and improves the recovery efficiency of the heavy metal ion.

Suzuki, Masafumi; Shoji, Tomoyoshi; Yoshimura, Noboru

166

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

167

Pesticide and heavy metal residues in Louisiana river otter  

E-print Network

PESTICIDE AND HEAVY METAL RESIDUES IN LOUISIANA RIVER OTTER A Thesis by DFBRA LYNN BECK Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTFR OF SCIENCE May 1977 Mcjor... ABSTRACT Pesticide and Heavy Natal Residues in Louisiana River Otter. (Mav 1977) Debra Lvnn Beck, B. S. , Utah State University Chairman of Advt. sorv Committee: Dr. . Tames 0. Teer River otter (Lutra canadensis) trapped in six areas of southern...

Beck, Debra Lynn

2012-06-07

168

RESPONSES OF LEGUME AND NONLEGUME CROP SPECIES TO HEAVY METALS IN SOILS WITH MULTIPLE METAL CONTAMINATION  

Microsoft Academic Search

Field and glasshouse investigations were conducted on the responses of two legumes (field pea and fodder vetch) and three non-leguminous crops (maize, wheat and rapeseed) to the heavy metals Cd, Cr, Zn, Pb, Cu and Mn in soil with multiple metal contamination. In general, the results indicate that the two legumes and wheat were more susceptible to soil metals than

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

2002-01-01

169

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

170

Heavy metals intake by cultured mushrooms growing in model system.  

PubMed

Micro element and heavy metal contents of mushrooms were determined by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). It was seen an increase in the heavy metal contents (except Cu and Zn) of the mushrooms until the second dose. A decrease was seen in heavy metal intake of the mushroom in the application of the third dose. The highest accumulation occurred from the upper soils treated with the second dose. Amounts of Cd, Cr, Cu, Pb and Zn, which were accumulated in the mushroom after the application of this dose, were detected as 5.7, 23.1, 75.7, 62.8 and 99.3 ppm, respectively. PMID:23591676

Ozcan, Mehmet Musa; Dursun, Nesim; Al Juhaimi, Fahad Y

2013-10-01

171

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

172

Biotechnol. Prog. 1995,11, 235-250 235 Biosorption of Heavy Metals  

E-print Network

Biotechnol. Prog. 1995,11, 235-250 235 REVIEW Biosorption of Heavy Metals B. Volesky*,?,*and Z. R, and uranium and also bind other heavy metals up to 25% of the biomass dry weight. Biosorption isotherm curves dispersed sources of dissolved and/or leached metals, large proportions of heavy metal species are released

Volesky, Bohumil

173

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

174

Long-Term Retention and Loss of Heavy Metals from Experimental Salt Marsh Plots  

E-print Network

Long-Term Retention and Loss of Heavy Metals from Experimental Salt Marsh Plots Katie Harrold Sippewissett Marsh I have tested the long-term retention of heavy metals by the marsh. Beginning in the early of fertilization. This could be due to sorbtion to organic matter and metal-oxides. Key Words: heavy metals, salt

Vallino, Joseph J.

175

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

176

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

177

Heavy Metal Binding and Removal by Phormidium  

Microsoft Academic Search

Bioremediation is growing in importance for the clean up of contaminated soil and ground water. The technology of bioremediatio n is not only useful and economic, but also practicable. Among the different applications of bioremediation, this paper deals specifically with bioremediation of trace metals using Phormidium sp., an attached filamentous microalgae. The study was done mainly to identify metal adsorption

T. C. Wang; J. C. Weissman; G. Ramesh; R. Varadarajan; J. R. Benemann

1998-01-01

178

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

179

Heavy metal characterization of circulating fluidized bed derived biomass ash.  

PubMed

Although the direct combustion of biomass for energy that applies circulating fluidized bed (CFB) technology is steadily expanding worldwide, only few studies have conducted an environmental assessment of biomass ash thus far. Therefore, this study aims to integrate information on the environmental effects of biomass ash. We investigated the concentration of heavy metal in biomass ash samples (bottom ash, cyclone ash, and filter ash) derived from a CFB boiler that combusted agricultural and forest residues at a biomass power plant (2×12 MW) in China. Ash samples were gathered for the digestion and leaching test. The heavy metal content in the solution and the leachate was studied via an inductively coupled plasma-mass spectrometer and a Malvern Mastersizer 2000 mercury analyzer. Measurements for the chemical composition, particle size distribution, and the surface morphology were carried out. Most of the metals in cyclone ash particles were enriched, whereas Ti and Hg were enriched in filter ash. Residence time contributed most to heavy metal enrichment. Under HJ/T 300 conditions, the heavy metals showed serious leaching characteristics. Under EN 12457-2 conditions, leaching behavior was hardly detected. PMID:22840499

Li, Lianming; Yu, Chunjiang; Bai, Jisong; Wang, Qinhui; Luo, Zhongyang

2012-09-30

180

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

181

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

182

Susceptibility of Halobacteria to Heavy Metals  

PubMed Central

Sixty-eight halobacteria, including both culture collection strains and fresh isolates from widely differing geographical areas, were tested for susceptibility to arsenate, cadmium, chromium, cobalt, copper, lead, mercury, nickel, silver, and zinc ions by an agar dilution technique. The culture collection strains showed different susceptibilities, clustering into five groups. Halobacterium mediterranei and Halobacterium volcanii were the most metal tolerant, whereas Haloarcula californiae and Haloarcula sinaiiensis had the highest susceptibilities of the culture collection strains. Different patterns of metal susceptibility were found for all the halobacteria tested, and there was a uniform susceptibility to mercury and silver. All strains tested were multiply metal tolerant. PMID:16347350

Nieto, J. J.; Ventosa, A.; Ruiz-Berraquero, F.

1987-01-01

183

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

184

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

185

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

186

Heavy Metals Alter the Potency of Medicinal Plants  

Microsoft Academic Search

\\u000a Heavy metals, accumulated naturally in soil, surface water or through industrial and mining processes, pose a potential threat\\u000a to various terrestrial and aquatic organisms (Greeger 1999; Larison et al. 2000; Dwivedi and Dey 2002; Hsu et al. 2006; Dhir\\u000a et al. 2008). Exposure to high metal concentrations impinges on the growth and development of plants (Rout and Das 2003; Shanker

Sekh Abdul Nasim; Bhupinder Dhir

187

Biosorption of heavy metals by bacteria isolated from activated sludge  

Microsoft Academic Search

Twelve aerobic bacteria from activated sludge were isolated and identified. These included both Gram-positive (e.g., Bacillus) and Gram-negative (e.g., Pseudomonas) bacteria. The biosorption capacity of these strains for three different heavy metals (copper, nickel, and lead) was determined\\u000a at pH 5.0 and initial metal concentration of 100 mg\\/L. Among these 12 isolates, Pseudomonas pseudoalcaligenes was selected for further investigation owing

Wa C. Leung; Hong Chua; Waihung Lo

2001-01-01

188

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

189

Characterization of disposable optical sensors for heavy metal determination.  

PubMed

This paper presents the development, characterization and quality control of analytical methods based on the use of disposable optical sensors for determination of heavy metals. Chromogenic reagents such as 1-(2-pyridylazo)-2-naphthol, (2-pyridylazo)resorcinol, Zincon, Ferrozine, and Chromazurol S were used to develop optical sensors of heavy metal ions found as contaminants in pharmaceutical substances and products, such as Zn(II), Cu(II), Ni(II), Fe(II), and Fe(III). The chromogenic reagents were immobilized in polymeric membranes by spin-coating from cocktails containing all reagents needed. The methods were prevalidated using a comprehensive quality control strategy based on a system of mathematical/statistical testing and diagnosis of each prevalidation step. This system involved characterization of analytical groups; checking of two limiting groups; testing of data homogeneity; recognition of outliers; and determination of analytical functions, limiting values, precision and accuracy. The prevalidation strategy demonstrated the reliability of the proposed method and pointed out some limitations. Combining the optical sensors with multicomponent linear regression allowed simultaneous determination of multiple metals in synthetic mixtures with different compositions. Good agreement between experimental and theoretical amounts of heavy metals in the mixtures was obtained for the majority of sensors and metals. Even better agreement was obtained between the experimental and theoretical total amounts of metals in the mixtures. The proposed analytical methods were successfully applied to the determination of zinc in pharmaceutical preparations of insulin and the determination of metal mixtures in a commercial nasal spray of isotonic seawater. The reliable and sensitive individual optical sensors developed in this study may be useful for designing a multimembrane optical tongue that with appropriate further optimization can be used for screening heavy metals in various matrices. PMID:22608424

Vukovi?, Jadranka; Avidad, María Ariza; Capitán-Vallvey, Luis Fermín

2012-05-30

190

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

191

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

192

Chelate-Assisted Heavy Metal Movement Through the Root Zone  

NASA Astrophysics Data System (ADS)

Chelating agents are added to soil as a means to mobilize heavy metals for plant uptake during phytoremediation. Yet almost no studies follow the displacement of heavy metals through the vadose zone following solubilization with chelating agents. The objective of this work was to determine the movement of heavy metals through the soil profile and their absorption by barley (Hordeum vulgare L.) in a soil amended with biosolids and in the presence of a chelating agent (EDTA). Twelve columns 75 cm in height and 17 in diameter were packed with a Haynie very fine sandy loam (coarse-silty, mixed, calcareous, mesic Mollic Udifluvents) and watered with liquid biosolids applied at the surface at a rate of 120 kg N/ha. Three weeks after plants germinated, soil was irrigated with a solution of the disodium salt of EDTA added at a rate of 0.5 g/kg soil. Four treatments were imposed: columns with no plants and no EDTA; columns with no plants plus EDTA; columns with plants and no EDTA; and columns with plants and EDTA. Columns were watered intensively for 35 days until two pore volumes of water had been added, and the leachates were collected daily. With or without plants, columns with EDTA had lower total concentrations of Cu, Zn, Cd, Ni, and Pb in the surface 20 cm than columns without EDTA. Concentrations of the heavy metals in this layer were not afffected by the presence of roots. Iron in leachate was followed as an indicator metal for movement to groundwater. No iron appeared in the leachate without EDTA, either in the columns with plants or without plants. The peak concentration of iron in the leachate occurred three days earlier in the columns without plants and EDTA compared to the columns with plants and EDTA. The results indicated the importance of vegetation on retarding heavy metal leaching to groundwater during chelate-facilitated phytoremediation.

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

2001-12-01

193

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

194

Immunotoxicity of heavy metals in relation to Great Lakes.  

PubMed Central

Heavy metals including mercury, lead, and cadmium are present throughout the ecosystem and are detectable in small amounts in the Great Lakes water and fish. The main route of exposure of humans to these metals is via the ingestion of contaminated food, especially fish. Extensive experimental investigations indicated that heavy metals alter a number of parameters of the host's immune system and lead to increased susceptibility to infections, autoimmune diseases, and allergic manifestations. The existing limited epidemiologic data and data derived from in vitro systems in which human peripheral blood leukocytes were used suggested that the human immune system may also be at increased risk following exposure to these metals. The magnitude of the risk that the presence of such metals in the Great Lakes may pose to the human immune system, and consequently to their health, is not known. In this review, the available data with respect to potential adverse effects of heavy metals on the immune system of humans and experimental animals are discussed, and additional data requirements are suggested. PMID:8635436

Bernier, J; Brousseau, P; Krzystyniak, K; Tryphonas, H; Fournier, M

1995-01-01

195

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

196

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

197

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

198

Surfactin restores and enhances swarming motility under heavy metal stress.  

PubMed

The present work reports the importance of lipopeptide biosurfactant on swarming motility of multi-metal resistant (MMR) bacterium under heavy metal stress. The MMR bacteria strain CM100B, identified as Bacillus cereus, was isolated from the coal mine sample. The strain was able to grow and reduce several metals namely Cd(2+), Co(2+), Cu(2+), Ni(2+), Mn(2+) and Pb(2+) ions which are common environmental pollutants. Presence of toxic heavy metal ions in the swarming medium significantly altered the motility of CM100B. Presence of Cd(2+) and Pb(2+) ions inhibited development of peritrichous flagella, thus inhibiting swarming motility. However, the addition of anionic biosurfactant surfactin restored (in case of Cd(2+) and Pb(2+) ions) or enhanced (in case of Co(2+), Cu(2+), Ni(2+) and Mn(2+)) the swarming ability of CM100B. Zeta potential studies for determining bacterial cell surface charge indicated that surfactin provided a suitable swarming environment to bacteria even under metal stress by chelating to cationic metal ions. Non-ionic surfactant Triton X-100 was unable to restore swarming under Cd(2+) and Pb(2+) ion stress. Thus, suggesting that surfactin can aid in motility not only by reducing the surface tension of swarming medium but also by binding to metal ions in the presence of metal ions stress. PMID:24441179

Singh, Anil Kumar; Dhanjal, Soniya; Cameotra, Swaranjit Singh

2014-04-01

199

Effects of heavy metal pollution on the soil microbial activity  

Microsoft Academic Search

The effects of heavy metals on soil microbial processes were investigated over a period of six weeks. Analytical grade (Sigma) sulphate salts of copper, zinc and nickel were added individually and in combinations to soil samples and incubated in different plastic pots. Samples were taken from the pots forthnightly and the rates of microbial carbon and nitrogen mineralization, microbial biomass

C. O. Nwuche; E. O. Ugoji

2008-01-01

200

Heavy metal resistant strains are widespread along Streptomyces phylogeny.  

PubMed

The genus Streptomyces comprises a group of bacteria species with high economic importance. Several of these species are employed at industrial scale for the production of useful compounds. Other characteristic found in different strains within this genus is their capability to tolerate high level of substances toxic for humans, heavy metals among them. Although several studies have been conducted in different species of the genus in order to disentangle the mechanisms associated to heavy metal resistance, little is known about how they have evolved along Streptomyces phylogeny. In this study we built the largest Streptomyces phylogeny generated up to date comprising six genes, 113 species of Streptomyces and 27 outgroups. The parsimony-based phylogenetic analysis indicated that (i) Streptomyces is monophyletic and (ii) it appears as sister clade of a group formed by Kitasatospora and Streptacidiphilus species, both genera also monophyletic. Streptomyces strains resistant to heavy metals are not confined to a single lineage but widespread along Streptomyces phylogeny. Our result in combination with genomic, physiological and biochemical data suggest that the resistance to heavy metals originated several times and by different mechanisms in Streptomyces history. PMID:23247041

Alvarez, Analía; Catalano, Santiago A; Amoroso, María Julia

2013-03-01

201

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

202

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

203

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

204

Heavy metal distribution in sediments of Krishna River basin, India  

Microsoft Academic Search

Suspended and bed sediments collected from the entire region of the Krishna River and its major tributaries were analyzed for heavy metals (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and Pb) by the thin-film energy dispersive x-ray fluorescence technique. There is considerable variation in the concentration of elements towards downstream, which may be due to the variation in the

R. Ramesh; V. Subramanian; R. van Grieken

1990-01-01

205

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

206

Parasites as Accumulation Indicators of Heavy Metal Pollution  

Microsoft Academic Search

Parasites are attracting increasing interest from parasite ecologists as potential indicators of environmental quality because of the variety of ways in which they respond to anthropogenic pollution. However, until recently, little was known about the accumulation of toxins within parasites. Certain parasites, particularly intestinal acanthocephalans and cestodes of fish, can accumulate heavy metals at concentrations that are orders of magnitude

B. Sures; R. Siddall; H. Taraschewski

1999-01-01

207

Heavy metal pollution disturbs immune response in wild ant populations  

Microsoft Academic Search

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

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

2007-01-01

208

Heavy metal pollution of river Ganga in Mirzapur, India  

Microsoft Academic Search

A study on the heavy metal pollution of River Ganga in the Mirzapur region, India has revealed that the river is polluted. The samples were collected from both the confluence of sewers and the river and from midstream points. The river is the dumping ground for domestic, municipal and industrial effluents. All the samples were analysed for certain physiochemical parameters

Y. C. Sharma; G. Prasad; D. C. Rupainwar

1992-01-01

209

Assessment of Heavy Metals in a Municipal Solid Waste Dumpsite  

Microsoft Academic Search

Unorganized dumping of solid waste is predominant in developing countries like India and cause adverse impacts to the environment. Sources such as electronic goods, electro plating waste, painting waste, used batteries, etc., when dumped with municipal solid wastes increase the heavy metals in dumpsites. Similarly solid waste dumping without the separation of hazardous waste can raise toxic environmental effects. Slow

S. Esakku; K. Palanivelu; Kurian Joseph

210

Uptake of Heavy Metals in Landfill Leachate by Vetiver Grass  

Microsoft Academic Search

Many waste disposal sites in Thailand are sources of environmental pollution because waste is still largely disposed of at these places without effective and proper management control. Landfill leachate usually contains high concentrations of heavy metals that are seriously harmful to the environment and human health. The study was conducted using vetiver for phyto-remedying soil contaminated with landfill leachate. Surat

Nualchavee Roongtanakiat; Tanasun Nirunrach; Supitcha Chanyotha; Diti Hengchaovanich

2003-01-01

211

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...

212

Sorption of heavy metal cations on activated carbon  

Microsoft Academic Search

Activated carbon is used to remove trace amounts of organic compounds from waters and wastewaters. An experimental program was conducted to determine the kinetics of sorption of lead, copper, and zinc on the surface of the powdered activated carbon Nuchar SA, and on granular activated carbon Filtrasorb 400. The results of the experimental program showed that sorption of heavy metals

Wilczak

1988-01-01

213

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

214

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...

215

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

216

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

217

Fate of heavy metals and agrochemicals in biochar amended soils  

Technology Transfer Automated Retrieval System (TEKTRAN)

Heavy metals and agrochemicals are the key targets for biochar-induced mitigation of runoff/groundwater contamination. Inorganic and organic contaminants interact differently with biochars as well as soil components. Mechanistic understandings are needed on sorption, desorption, and competitive sor...

218

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

219

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

220

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

221

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 (>0.39mgkg(-1)) and Cu (>1981mgkg(-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

222

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, ...

223

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

224

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

225

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

226

Fractionation of heavy metals in pavement runoff  

Microsoft Academic Search

Abstract The transport of anthropogenic constituents by runoff from urban roadways can adversely impact the quality of adjacent receiving waters and soils. Metal elements are the most,persistent constituents found in pavement,runoff. A section of urban highway pavement in Cincinnati, Ohio, USA with an average daily traffic count of 150 000 vehicles was instrumented to sample lateral sheet flow from the

John J. Sansalone; Steven G. Buchberger; Souhail R. Al-abed

1996-01-01

227

Heavy metal pollution abatement using rock phosphate mineral.  

PubMed

The low-grade rock phosphate of Jhabua, Madhya Pradesh (India), was investigated for its possible application in the removal of lead, copper, zinc and cobalt ions from aqueous solutions. Effects of contact time, amount of adsorbent and initial concentration of metal ions were studied. Adsorption of heavy metal ions was found to follow the order: Pb2+ > Cu2+ > Zn2+ > Co2+. The probable mechanism of metal ions removal by rock phosphate was found to be by its dissolutions followed by subsequent precipitation. PMID:16229891

Saxena, Sona; D'Souza, S F

2006-02-01

228

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

229

Chemical binding of heavy metals in anoxic river sediments.  

PubMed

Acid volatile sulfides (AVS) in sediments are available for binding with divalent cationic metals through the formation of insoluble metal-sulfide complexes, thereby controlling the metal bioavailability and subsequent toxicity to benthic biocommunities. However, when the molar concentrations of simultaneously extracted metals (SEM) were greater than AVS, the unexpectedly low or nondetectable levels of metal in pore water could also be found. Thus, except AVS, additional binding phases in sediments were supposed to provide the binding sites for SEM. The aims of this study are to realize the spatial distribution of AVS, SEM, and other binding phases of heavy metals in anoxic sediments of the Ell-Ren river and to elucidate what may be the main additional binding phases except AVS in the anoxic river sediments. By comparing the spatial distributions of SEM/ AVS ratio with various binding phases in extremely anoxic sediments (redox potential was between -115 and -208 mV), both organic matter and carbonates could be considered to be the main additional binding phases of SEM other than AVS. In addition, AVS appeared to have the priority to bind with SEM. By comparing the binding phases of heavy metals before and after AVS extraction, it could be found that Fe-oxides could also be considered to be the main additional binding phase associated with Zn in slightly anoxic sediments (redox potential was between -50 and -130mV), while organic matter with Cu being the next. PMID:11791838

Yu, K C; Tsai, L J; Chen, S H; Ho, S T

2001-12-01

230

Heavy metals in medicinal and fodder plants of the negev desert  

Microsoft Academic Search

The concentrations of heavy metals (zinc, copper, iron, manganese, cadmium, lead and nickel) were measured in 51 desert plants, of which 42 are considered medicinal, three fodder and six common plant species. Accumulation of certain heavy metals in some plant species was 2 ? 260?fold higher than the available heavy metal content of the soil of the Negev desert.The highest

P. Sathiyamoorthy; P. Van Damme; M. Oven

1997-01-01

231

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

232

Assessment of heavy metal uptake and translocation in Dyera costulata for phytoremediation of cadmium contaminated soil  

Microsoft Academic Search

Heavy metal pollution is a widespread global problem causing serious environmental concern. Cadmium, one of the heavy metals, is water soluble and can be transferred from soil to plants and enter into the food chain. It is detrimental to human health because it accumulates in the body and can cause renal tubular dysfunction, pulmonary emphysema and osteoporosis. This heavy metal

Nik M. Majid; M. M. Islam; Redzuan Abdul Rauf; Parisa Ahmadpour; Arifin Abdu

2011-01-01

233

Assessment of heavy metal uptake and translocation in Dyera costulata for phytoremediation of cadmium contaminated soil  

Microsoft Academic Search

Heavy metal pollution is a widespread global problem causing serious environmental concern. Cadmium, one of the heavy metals, is water soluble and can be transferred from soil to plants and enter into the food chain. It is detrimental to human health because it accumulates in the body and can cause renal tubular dysfunction, pulmonary emphysema and osteoporosis. This heavy metal

Nik M. Majid; M. M. Islam; Redzuan Abdul Rauf; Parisa Ahmadpour; Arifin Abdu

2012-01-01

234

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

235

Temporal variation of heavy metal contamination in fish of the river lot in southern France  

E-print Network

July 2009 Keywords: Heavy metals Historical pollution Freshwater fish Muscle Liver Quality index a b of intense heavy metal pollution and has been the focus of studies dating back to the 1970s (Audry et al Lot is derived from anthropogenic origin. As such, the main sources of heavy metal pollution

Grenouillet, Gael

236

New Methods of Cleaning Up Heavy Metal in Soils and Water  

Microsoft Academic Search

There are several options for treating or cleaning up soils contaminated with heavy metals. This paper discusses three of those methods. Introduction At many sites around the nation, heavy metals have been mined, smelted, or used in other industrial processes. The waste (tailings, smelter slag, etc.) has sometimes been left behind to pollute surface and ground water. The heavy metals

Otto H. York

237

EVALUATION OF HEAVY METALS BIOSORPTION IN AQUEOUS EFFLUENT BY A BACTERIAL EXTRACELLULAR POLYMERIC SUBSTANCE  

Microsoft Academic Search

Bioremediation of heavy metal pollution remains a major challenge in environmental Biotechnology. Some industrial processes results in the release of heavy metals into aquatic systems. This has led to increasing concern about the effect of toxic heavy metals as environmental pollutants. One of the approaches considered for application involves biosorption either to biomass or to isolated biopolymers, as a more

Alexandre Fábio Azamor de Oliveira; José Pereira da Silva; Selma Gomes Ferreira Leite; Escola de Química

238

Root development and heavy metal phytoextraction efficiency: comparison of different plant species in the field  

Microsoft Academic Search

Heavy metal phytoextraction is a soil remediation technique which implies the optimal use of plants to remove contamination from soil. Plants must thus be tolerant to heavy metals, adapted to soil and climate characteristics and able to take up large amounts of heavy metals. Their roots must also fit the spatial distribution of pollution. Their different root systems allow plants

Catherine Keller; Daniel Hammer; Achim Kayser; Walter Richner; Michèle Brodbeck; Manfred Sennhauser

2003-01-01

239

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

240

Research on Institutional Innovations in Control of Soil Pollution by Heavy Metal in Zhejiang  

Microsoft Academic Search

With rapid development of economy, the heavy metal pollution in soil has been a serious environmental problem in Zhejiang. The typical events of heavy metal pollution happened in Taizhou, Changxing, Fuyang & Ningbo. Under background of environmental law, environmental taxes, remediation & development of Brownfield and environmental labeling, etc, the research focuses on the situation of heavy metal pollution in

Xiaohong Liu; Xijun Yu

2010-01-01

241

Integrated Vetiver Technique for Remediation of Heavy Metal Contamination: Potential and Practice  

Microsoft Academic Search

Metalliferous mining activities produce a large quantity of waste materials (such as tailings), which frequently contain excessive concentrations of heavy metals. These mining activities and waste materials have created heavy metal pollution problems through wind and water erosion. An integrated vetiver technique (IVT) for remediation of heavy metal contamination raised from mining activities is suggested in this paper. The remediation

Wensheng Shu; Hanping Xia

242

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

243

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

244

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 investigate the spatial distribution of anthropogenic pollutants. The concentrations of heavy metals, organic carbon and particle size were examined in all samples. Large spatial variations of heavy metals and particle size were observed. The highest concentrations of heavy metals were

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

2006-01-01

245

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

246

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

247

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

248

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

249

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.

250

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

251

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

E-print Network

IMPACT OF HEAVY METALS IN SEWAGE SLUDGE ON SOIL AND PLANTS (COLZA and WHEAT) Najla LASSOUED1@emse.fr Abstract We are testing the impact of heavy metals in sludge from urban and industrial wastewater treatment of heavy metals, however rape (colza) is a plant of the family Brassica napus, is an excellent bio

Paris-Sud XI, Université de

252

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

253

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.

254

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

255

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.

256

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

257

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

258

Do Heavy Metal Concentrations Pose a Threat to Marine Turtles from the  

E-print Network

Do Heavy Metal Concentrations Pose a Threat to Marine Turtles from the Mediterranean Sea? BRENDAN J Concentrations of heavy metals (Hg, Cd and Pb) were determined in internal organs and nest contents of green- sented here are consistent with inter-speci®c dierences in diet and trophic status. Heavy metal burdens

Exeter, University of

259

Executive Summary The remediation of radionuclides and heavy metals using current technology is generally  

E-print Network

vii Executive Summary The remediation of radionuclides and heavy metals using current technology stages of development of nanotechnology applications for remediation of radionuclides and heavy metals radionuclides and heavy metals is a promising development. Though a recently-emerged technology, the LOC device

260

Mercury and Other Heavy Metals Influence Bacterial Community Structure in Contaminated Streams  

E-print Network

Mercury and Other Heavy Metals Influence Bacterial Community Structure in Contaminated Streams.C. Brandt, and D.A. Elias. 2011. Mercury and other heavy metals influence bacterial community structure and Other Heavy Metals Influence Bacterial Community Structure in Contaminated Streams Contact: Dwayne A

261

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

262

Original article Mobility of heavy metals in soil and their uptake  

E-print Network

Original article Mobility of heavy metals in soil and their uptake by sunflowers grown at different) Abstract - A pot trial was carried out to study the effect of heavy metals on sunflowers (Helianthus annuus L.) grown on three different soils at different levels of heavy metal loading (added in 1987

Paris-Sud XI, Université de

263

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

264

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...

265

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

266

Heavy metals removal by sand filters inoculated with metal sorbing and precipitating bacteria  

Microsoft Academic Search

Large volumes of wastewater containing metals such as Cd, Zn, Cu, Pb, Hg, Ni or Co are mainly treated by precipitation processes. However, waters treated in such ways do not always meet regulatory standards. And in many cases, ecotaxes must be paid on the heavy metals load in the discharged water. Therefore, a second polishing treatment is often necessary. In

L. Diels; P. H. Spaans; S. Van Roy; L. Hooyberghs; A. Ryngaert; H. Wouters; E. Walter; J. Winters; L. Macaskie; J. Finlay; B. Pernfuss; H. Woebking; T. Pümpel; M. Tsezos

2003-01-01

267

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

268

Concentration of heavy metals in ash produced from Lithuanian forests  

NASA Astrophysics Data System (ADS)

Wood ash contains important amounts of heavy metals. This quantity depends on burned specie, temperature of exposition and heat duration time. Due the high mineralization imposed by the temperatures, ash is used as lime product in agriculture and forests. Also, after a forest fire large quantities of ash are produced and distributed in soil surface. This mineralized organic matter can induce important environmental problems, including soil toxicity provoked by heavy metals leachates from ash. There is an extensive literature about heavy metals contents on ash in different species. However, it recently highlighted that the same species placed in different environments can respond diversely to same temperatures. This question is of major importance because temperature effects on severity can be a function of the plant communities instead of specie characteristics. These findings add a higher degree of complexity in the understanding of temperature effects on ash composition and consequent availability of heavy metals. The aim of this study is to compare the ash chemical heavy metal composition, Cobalt (Co), Chromium (Cr), Cooper (Cu), Silver (Ag), Lead (Pb), Nickel (Ni), Manganese (Mn) and Zinc (Zn), from Pinus sylvestris and Betula pendula, collected in key and representative areas of Lithuanian forests, located in southern, coastal and central part. Samples were collected from alive trees, taken to laboratory and air dried. Subsequently were crushed and submitted to muffle furnace at temperature of 550°C during two hours. The ash samples were digested and in a HNO3-HCl solution and then analysed with AAS. Comparisons between species and sites were performed with a Non-parametric one-way ANOVA‘s on rank transformed data followed by Tukey‘s HSD, significant at a p<0.05. Results showed significant difference between Co and Ag concentrations between Pinus sylvestris and Betula pendula. Also, significantly different concentrations of Pb, Cu, Ni and Mn were determined among investigated sites. No significant difference was found for Zn and Cr among investigated sites. Variation of metals between sites and stands can be explained by their age, flammability difference between plant communities and anthropogenic heavy metal load. These and other aspects will be discussed with more detail in the communication.

Baltrenaite, Edita; Pereira, Paulo; Butkus, Donatas; Úbeda, Xavier

2010-05-01

269

Interaction of heavy metals and pyrene on their fates in soil and tall fescue (Festuca arundinacea).  

PubMed

90-Day growth chamber experiments were performed to investigate the interactive effect of pyrene and heavy metals (Cu, Cd, and Pb) on the growth of tall fescue and its uptake, accumulation, and dissipation of heavy metals and pyrene. Results show that plant growth and phytomass production were impacted by the interaction of heavy metals and pyrene. They were significantly decreased with heavy metal additions (100-2000 mg/kg), but they were only slightly declined with pyrene spiked up to 100 mg/kg. The addition of a moderate dosage of pyrene (100 mg/kg) lessened heavy metal toxicity to plants, resulting in enhanced plant growth and increased metal accumulation in plant tissues, thus improving heavy metal removal by plants. In contrast, heavy metals always reduced both plant growth and pyrene dissipation in soils. The chemical forms of Cu, Cd, and Pb in plant organs varied with metal species and pyrene addition. The dissipation and mineralization of pyrene tended to decline in both planted soil and unplanted soils with the presence of heavy metals, whereas they were enhanced with planting. The results demonstrate the complex interactive effects of organic pollutants and heavy metals on phytoremediation in soils. It can be concluded that, to a certain extent, tall fescue may be useful for phytoremediation of pyrene-heavy metal-contaminated sites. Further work is needed to enhance methods for phytoremediation of heavy metal-organics co-contaminated soil. PMID:24383577

Lu, Mang; Zhang, Zhong-Zhi; Wang, Jing-Xiu; Zhang, Min; Xu, Yu-Xin; Wu, Xue-Jiao

2014-01-21

270

Environmental health implications of heavy metal pollution from car tires.  

PubMed

This paper reviews the potential for environmental pollution by heavy metals from the disposal of used car tires and describes laboratory work and field research exploring the magnitude of the problem. The metals considered here are cadmium, lead, and zinc; their respective mean concentrations for ten makes of tires used in the United Kingdom ranged from 0-3.0, 8.1-22.3, and 2524-6012 ppm. The metals were extracted from tires by simulated acid-rain solutions (pH 2.5); zinc concentrations of the leachate ranged from 169-463 ppm, but cadmium and lead concentrations were negligible. A significant increase in surface soil concentrations of all three metals was measured with increasing proximity to a tire dump in West London. The respective mean concentrations of cadmium, lead, and zinc in soil at the base of the dump were 22, 1160, and 1235 ppm, indicating contamination by each metal. PMID:9085433

Horner, J M

1996-01-01

271

Utilization of pulp and paper industrial wastes to remove heavy metals from metal finishing wastewater.  

PubMed

Two pulp and paper industrial wastes, lime mud (LM) and recovery boiler ash (RB), have low moisture contents, low heavy metal contaminations and contain various carbonate compounds which contribute to a high pH. Metal finishing wastewater (MF-WW) has a low pH, high levels of TDS and high contaminations from Cr, Cu, Pb and Zn. The heavy metals from MF-WW were removed by sorption and precipitation mechanisms. LM gave better results in removing heavy metals from MF-WW than RB. At a reaction time of 45min, the maximum removal efficiencies for Cr (93%) and Cu (99%) were obtained at 110gL(-1) of LM, but at 80gL(-1) for Pb (96%) and Zn (99%). Treatment with LM gives a higher sludge volume than with RB. However, the leachability of heavy metals from LM is lower. Leachability of heavy metals in the sediment for all selected treatment conditions is within government standards. PMID:19501952

Sthiannopkao, Suthipong; Sreesai, Siranee

2009-08-01

272

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

273

Effect of the militarily-relevant heavy metals, depleted uranium and heavy metal tungsten-alloy on gene expression in human liver carcinoma cells (HepG2)  

Microsoft Academic Search

Depleted uranium (DU) and heavy-metal tungsten alloys (HMTAs) are dense heavy-metals used primarily in military applications. Chemically similar to natural uranium, but depleted of the higher activity 235U and 234U isotopes, DU is a low specific activity, high-density heavy metal. In contrast, the non-radioactive HMTAs are composed of a mixture of tungsten (91–93%), nickel (3–5%), and cobalt (2–4%) particles. The

Alexandra C. Miller; Kia Brooks; Jan Smith; Natalie Page

2004-01-01

274

Contrasting effects of heavy metals on sponge cell behavior.  

PubMed

Mediterranean coastal areas are highly contaminated by heavy metals, which have been reported to produce harmful effects in marine organisms. Sponges are particularly vulnerable to waterborne metals because they are able to process large amounts of water. Dissociated sponge cells can move in response to external stimuli, and the cell body changes shape through production of pseudopodia and phylopodia. We studied for first time the effects of heavy metals (cadmium copper and mercury) on motility and aggregation of isolated sponge cells. Cell shape was assessed by using several shape indices. The three metals studied induced changes of different sign on cell shape. Mercury arrested movement of sponge cells, which tended to be rounded, without pseudopodia. In contrast, moderate concentrations of copper and cadmium enhanced pseudopodia formation and cell motility. On the other hand, the three metals enhanced cell aggregation at the concentrations assayed. Our results show that sponge cells respond to metal pollution in different ways and that these responses can be assessed by calculating several shape indices. PMID:17594047

Cebrian, Emma; Uriz, María Jesús

2007-11-01

275

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

276

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

277

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

278

Characterization of a Novel Plant Promoter Specifically Induced by Heavy Metal and Identification of the Promoter Regions Conferring Heavy Metal Responsiveness1  

PubMed Central

The bean (Phaseolus vulgaris) stress-related gene number 2 (PvSR2) gene responds to heavy metals but not to other forms of environmental stresses. To elucidate its heavy metal-regulatory mechanism at the transcriptional level, we isolated and characterized the promoter region (?1623/+48) of PvSR2. Deletions from the 5? end revealed that a sequence between ?222 and ?147 relative to the transcriptional start site was sufficient for heavy metal-specific induction of the promoter region of PvSR2. Detailed analysis of this 76-bp fragment indicated that heavy metal-responsive elements were localized in two regions (?222/?188 and ?187/?147), each of which could separately confer heavy metal-responsive expression on the ?-glucuronidase gene in the context of a minimal cauliflower mosaic virus 35S promoter. Region I (?222/?188) contains a motif (metal-regulatory element-like sequence) similar to the consensus metal-regulatory element of the animal metallothionein gene, and mutation of this motif eliminated the heavy metal-inducible function of region I. Region II (?187/?147) had no similarity to previously identified cis-acting elements involved in heavy metal induction, suggesting the presence of a novel heavy metal-responsive element. Transformed tobacco (Nicotiana tabacum) seedlings expressing ?-glucuronidase under control of the PvSR2 promoter region (?687/+48) showed heavy metal-specific responsive activity that depended on the type and concentration of the heavy metal and the type of organ. These findings further our understanding of the regulation of PvSR2 expression and provide a new heavy-metal-inducible promoter system in transgenic plants. PMID:16861574

Qi, Xiaoting; Zhang, Yuxiu; Chai, Tuanyao

2007-01-01

279

Bioremediation of heavy metals in liquid media through fungi isolated from contaminated sources.  

PubMed

Wastewater particularly from electroplating, paint, leather, metal and tanning industries contain enormous amount of heavy metals. Microorganisms including fungi have been reported to exclude heavy metals from wastewater through bioaccumulation and biosorption at low cost and in eco-friendly way. An attempt was, therefore, made to isolate fungi from sites contaminated with heavy metals for higher tolerance and removal of heavy metals from wastewater. Seventy-six fungal isolates tolerant to heavy metals like Pb, Cd, Cr and Ni were isolated from sewage, sludge and industrial effluents containing heavy metals. Four fungi (Phanerochaete chrysosporium, Aspegillus awamori, Aspergillus flavus, Trichoderma viride) also were included in this study. The majority of the fungal isolates were able to tolerate up to 400 ppm concentration of Pb, Cd, Cr and Ni. The most heavy metal tolerant fungi were studied for removal of heavy metals from liquid media at 50 ppm concentration. Results indicated removal of substantial amount of heavy metals by some of the fungi. With respect to Pb, Cd, Cr and Ni, maximum uptake of 59.67, 16.25, 0.55, and 0.55 mg/g was observed by fungi Pb3 (Aspergillus terreus), Trichoderma viride, Cr8 (Trichoderma longibrachiatum), and isolate Ni27 (A. niger) respectively. This indicated the potential of these fungi as biosorbent for removal of heavy metals from wastewater and industrial effluents containing higher concentration of heavy metals. PMID:23024411

Joshi, P K; Swarup, Anand; Maheshwari, Sonu; Kumar, Raman; Singh, Namita

2011-10-01

280

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

281

Heavy Metals Contamination in Coastal Sediments of Karachi, Pakistan  

NASA Astrophysics Data System (ADS)

Toxic compounds such as heavy metals exert chronic and lethal effects in animals, plants, and human health. With the rapid industrialization, urbanization, and economic development in Karachi, heavy metals are continuing to be introduced to estuarine and coastal environment through rivers, runoff and land-based point sources. Pollution in the Karachi coastal region (167 km long) is mainly attributed to Lyari and Malir Rivers flowing through the city of Karachi. Both rivers are served by various channels of domestic and industrial wastes carrying more than 300 million gallons per day untreated effluent of 6000 industries and ultimately drain into the beaches of Arabian Sea. Concentrations of selected heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in surface sediments from eighty-eight sites in Karachi coastal region were studied in order to understand metal contamination due to industrialization, urbanization, and economic development in Karachi. Sediment samples were collected in 2005 and 2006. We have found that heavy metal concentrations in surface sediments varied from 0.006 to 24.3 ug/g for Cd, 5.1 to 95 ug/g for Co, 2.9 to 571 ug/g for Cr, 6.9 to 272 ug/g for Cu, 0.55 to 6.5% for Fe, 1.2 to 318 ug/g for Mn, 7.5 to 75 ug/g for Ni, 6.3 to 121 ug/g for Pb, and 3.3 to 389 ug/g for Zn. Enrichment factors (EFs) were calculated to assess whether the concentrations observed represent background or contaminated levels. The highest levels of metals were found to be at the confluence of the Lyari and Malir River streams at the Arabian Sea, indicating the impact of the effluents of the highly urbanized and industrialized city of Karachi. Furthermore, this study assessed heavy metal toxicity risk with the application of Sediment Quality Guideline (SQG) indices (effect range low/effect range median values, ERL/ERM). Results indicated that the potential toxicity of marine environment can cause adverse biological effects to the biota directly and the human health indirectly through food web chain.

Siddique, A.; Mumtaz, M.; Zaigham, N. A.; Mallick, K. A.; Saied, S.; Khwaja, H. A.

2008-12-01

282

Occurrence of heavy metal binding phytochelatins in plants growing in a mining refuse area  

Microsoft Academic Search

Summary Phytochelatins were identified in roots of heavy metal-sensitiveAcer pseudoplatanus and-resistantSilene cucubalus plants grown in zinc-rich soil of a mine dump. Both plants, when collected from a metal-uncontaminated stand, located nearby, revealed no phytochelatins. Thus, we concluded that metal-binding phytochelatins are specifically induced in plants of heavy metal enriched ecosystems.

E. Grill; E.-L. Winnacker; M. H. Zenk

1988-01-01

283

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 ...

284

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

285

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

286

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

287

Heavy-electron metals - New highly correlated states of matter  

NASA Astrophysics Data System (ADS)

Conduction-electron masses two orders of magnitude greater than the free-electron mass have been noted in heavy-electron metals at liquid-He temperatures. Variously characterizable as normal, antiferromagnetic, or superconducting, this highly correlated electronic behavior stands in striking contrast with the ordinary metallic case. It is presently judged that the physical origin of these large-mass, superconducting, and magnetic properties lies in the strong coupling between the conduction electrons and the local f-electron moment fluctuations that are typical of these materials.

Fisk, Z.; Hess, D. W.; Pethick, C. J.; Pines, D.; Smith, J. L.

1988-01-01

288

Removal of trace heavy metals by solid?liquid separation  

Microsoft Academic Search

Highly sensitive and economical methods have been developed for the removal of trace heavy metal ions such as Cr(III), Fe(III), Co(II), Ni(II), Cu(II), Ru(III), Rh(III), Pd(II), Os(VIII), Ir(III) and Pt(IV), present in a large aqueous volume by absorption of their Phenanthrenequinone Monoximes (PQM) chelates on microcrystalline naphthalene in different pH ranges in a fluidized bed reactor. The above metal?PQM chelates

S. A. Wasay; B. K. Puri

1993-01-01

289

Adherent bacteria in heavy metal contaminated marine sediments.  

PubMed

The eubacterial communities adherent to sediment particles were studied in heavy metal contaminated coastal sediments. Six sampling sites on the Belgian continental plate and presenting various metal loads, granulometries, and organic matter content, were compared. The results indicated that the total microbial biomass (attached + free-living bacteria) was negatively correlated to HCl-extractable metal levels (p<0.05) and that the percentage of cells adherent to sediment particles was close to 100% in every site even in highly contaminated sediments. Consequently, it seems that heavy metal contamination does affect total bacterial biomass in marine sediments but that the ratio between attached and free living microorganisms is not affected. The composition of the eubacterial communities adherent to the fine fraction of the sediments (<150 microm) was determined using fluorescent in situ hybridisation (FISH). The FISH results indicated that the proportion of gamma- and delta-Proteobacteria, and Cytophaga-Flexibacter-Bacteroides (CFB) bacteria, was not related to the HCl extractable metal levels. Most of the 79 complete 16S rRNA sequences obtained from the attached microbial communities were classified in the gamma- and delta-Proteobacteria and in the CFB bacteria. A large proportion of the attached gamma-Proteobacterial sequences found in this study (56%) was included in the uncultivated GMS clades that are indigenous to marine sediments. PMID:17453724

Gillan, David C; Pernet, Philippe

2007-01-01

290

The proteomics of heavy metal hyperaccumulation by plants.  

PubMed

Hyperaccumulators are distinguished from non-hyperaccumulators on the basis of their capacity to extract heavy metal ions from the soil, their more efficient root-to-shoot translocation of these ions and their greater ability to detoxify and sequester heavy metals in the shoot. The understanding of the mechanisms underlying metal ion accumulation has progressed beyond the relevant biochemistry and physiology to encompass the genetic and molecular regulatory systems which differentiate hyperaccumulators from non-hyperaccumulators. This paper reviews the literature surrounding the application of proteomics technology to plant metal hyperaccumulation, in particular involving the elements As, Cd, Cu, Ni, Pb and Zn. The hyperaccumulation process across a number of unrelated plant species appears to be associated with proteins involved in energy metabolism, the oxidative stress response and abiotic and biotic stress. The relevance of transducers of the metal stress response to the phenomenon of hyperaccumulation is summarized. Proteomic data complement the more voluminous genomic and transcriptomic data sets in providing a more nuanced picture of the process, and should therefore help in the identification of the major genetic determinants of the hyperaccumulation phenomenon. PMID:23268120

Visioli, Giovanna; Marmiroli, Nelson

2013-02-21

291

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

292

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

293

Synthesis and heavy metal immobilization behaviors of slag based geopolymer.  

PubMed

In this paper, two aspects of studies are carried out: (1) synthesis of geopolymer by using slag and metakaolin; (2) immobilization behaviors of slag based geopolymer in a presence of Pb and Cu ions. As for the synthesis of slag based geopolymer, four different slag content (10%, 30%, 50%, 70%) and three types of curing regimes (standard curing, steam curing and autoclave curing) are investigated to obtain the optimum synthesis condition based on the compressive and flexural strength. The testing results showed that geopolymer mortar containing 50% slag that is synthesized at steam curing (80 degrees C for 8h), exhibits higher mechanical strengths. The compressive and flexural strengths of slag based geopolymer mortar are 75.2 MPa and 10.1 MPa, respectively. Additionally, Infrared (IR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques are used to characterize the microstructure of the slag based geopolymer paste. IR spectra show that the absorptive band at 1086 cm(-1) shifts to lower wave number around 1007 cm(-1), and some six-coordinated Als transforms into four-coordination during the synthesis of slag based geopolymer paste. The resulting slag based geopolymeric products are X-ray amorphous materials. SEM observation shows that it is possible to have geopolymeric gel and calcium silicate hydrate (C-S-H) gel forming simultaneously within slag based geopolymer paste. As for immobilization of heavy metals, the leaching tests are employed to investigate the immobilization behaviors of the slag based geopolymer mortar synthesized under the above optimum condition. The leaching tests show that slag based geopolymer mortar can effectively immobilize Cu and Pb heavy metal ions, and the immobilization efficiency reach 98.5% greater when heavy metals are incorporated in the slag geopolymeric matrix in the range of 0.1-0.3%. The Pb exhibits better immobilization efficiency than the Cu in the case of large dosages of heavy metals. PMID:17034943

Yunsheng, Zhang; Wei, Sun; Qianli, Chen; Lin, Chen

2007-05-01

294

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

295

Antioxidant, Heavy Metals and Elemental Analysis of Holoptelea integrifolia Planch  

PubMed Central

The ethanol crude extract of stem bark of Holoptelea integrifolia Planch. traditionally used in Indian system of medicine was screened for its antioxidant activity using ?-tocopherol as standard antioxidant. The free radical scavenging potential of the extract was evaluated by two different antioxidant methods; ferric thiocyanate and thiobarbituric acid method. The ethanol extract was found to exhibit good antioxidant property. Further physicochemical constants, elemental and heavy metal analysis of stem bark have been described. PMID:21394277

Saraswathy, A.; Devi, S. Nandini; Ramasamy, D.

2008-01-01

296

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

297

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

298

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

299

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

300

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

301

Ecophysiological responses of Empetrum nigrum to heavy metal pollution  

Microsoft Academic Search

Chlorophyll, organic (citric and malic acids) and abscisic acid (ABA) contents and stem water potential were measured to indicate possible physiological effects of heavy metal deposition on Empetrum nigrum L. (crowberry). The leaves and stems of E. nigrum were collected at distances of 0.5 and 8 km from the Cu–Ni smelter at Harjavalta, south-west Finland. All the investigated parameters were

S Monni; C Uhlig; E Hansen; E Magel

2001-01-01

302

Accumulation of Heavy Metals in Caspian Seals ( Phoca caspica )  

Microsoft Academic Search

Concentrations of heavy metals (Fe, Mn, Zn, Cu, Pb, Ni, Cd, Co, and Hg) were determined in the muscle, liver, and kidney of\\u000a 42 Caspian seals and fishes collected from the Caspian Sea in 1993. Higher Mn and lower Fe and Cu concentrations were found\\u000a in the liver in comparison with other marine pinnipeds. Lower Cu concentrations in the liver

I. Watanabe; T. Kunito; S. Tanabe; M. Amano; Y. Koyama; N. Miyazaki; E. A. Petrov; R. Tatsukawa

2002-01-01

303

Analysis of heavy metals in ecstasy tablets by electrochemical methods  

Microsoft Academic Search

Trace amounts of heavy metals have been analysed by electrochemical techniques in ecstasy tablets obtained from different police seizures in Spain. Lead, cadmium, copper and zinc were determined by differential-pulse anodic stripping voltammetry at a hanging mercury drop electrode, whereas nickel and cobalt were determined by adsorptive differential-pulse cathodic stripping voltammetry from their dimethylglyoxime complexes, M(DMG)2. The performance of the

Inmaculada Fierro; Rafael Pardo; Mariluz Tascón; Dolores Vázquez

2007-01-01

304

Heavy metal detection combining stripping electrochemistry and piezoelectric sensor technology  

NASA Astrophysics Data System (ADS)

Mercury and other toxic, heavy metals must be detected at part per billion levels in drinking water and environmental monitoring applications. No portable technology is presently capable of providing the required sensitivity, simplicity or reliability. Piezoelectric sensor technology and electrochemical technology have both offered sound approaches to the detection of these pollutants. Both exhibit limitations which prevent their widespread acceptance in water quality assurance and in environmental remediation.

French, Lester A.; Schweyer, Michael G.; Foley, Janet B.; Andle, Jeffrey C.; Watson, Charles; Bruce, Mitchell R.; Bruce, Alice E.; Vetelino, John F.

1998-12-01

305

Pentadienyl chemistry of the heavy alkaline-earth metals revisited.  

PubMed

Open-metallocenes of the heavy alkaline-earth metals [(?(5)-Pdl')2M(thf)n] (M = Ca (1), Sr (2), n = 1; M = Ba (3), n = 2; Pdl' = 2,4-tBu2C5H5) are readily prepared by salt-metathesis between MI2 and KPdl' and characterized by NMR spectroscopy and X-ray diffraction studies. PMID:24652227

Reiners, Matthias; Fecker, Ann Christin; Freytag, Matthias; Jones, Peter G; Walter, Marc D

2014-05-14

306

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

307

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

308

Thermal treatment of metal-enriched biomass produced from heavy metal phytoextraction.  

PubMed

Phytoextraction is an environmentally sound method for cleaning up sites that are contaminated with toxic heavy metals. However, the method has been questioned because it produces a biomass-rich secondary waste containing the extracted metals. Therefore, further treatment of this biomass is necessary. In this study, we investigated whether thermal treatment could be a feasible option for evaporatively separating metals from the plant residues. We used a laboratory scale reactor designed to simulate the volatilization behavior of heavy metals in a grate furnace. The evaporation of alkali and heavy metals from plant samples was investigated online, using a thermo-desorption spectrometer (TDS). Experiments were performed in the temperature range of 25-950 degrees C with leaves of the Cd and Zn hyperaccumulator Thlaspi caerulescens and of the high biomass plant Salix viminalis (willow), both grown on contaminated soils. Gasification (i.e., pyrolysis), which occurs under reducing conditions, was a better method than incineration under oxidizing conditions to increase volatilization and, hence subsequently recovery, of Cd and Zn from plants. It would also allow the recycling of the bottom ash as fertilizer. Thus, our investigations confirmed that incineration (or co-incineration) is a viable option for the treatment of the heavy metal-enriched plants. PMID:15926590

Keller, Catherine; Ludwig, Christian; Davoli, Frédéric; Wochele, Jörg

2005-05-01

309

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

310

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

311

Heavy Metals Concentrations in Groundwater Used for Irrigation  

PubMed Central

Background: The main objective of this study was characterization of selected heavy metals concentrations (Lead, cadmium, copper, zinc, nickel and chromium) in groundwater used for ir-rigation in Tabriz City's countryside. Methods: After consulting with the experts of agriculture department and site survey, 38 irriga-tion water samples were taken from different farms (34 wells) without primary coordination with farm owners. All of samples were acidified to achieve pH?2 and then were concentrated from 10 to 1 volume. The concentrations of Cd, Pb, Cu, Cr, Ni, and Zn in the samples (totally 228) were determined with a flame atomic absorption spectrophotometer. Results: In none of 38 farms, irrigation with surface runoff and industrial wastewater was ob-served. The average concentrations of Cd, Pb, Cu, Cr, Ni, and Zn in the irrigated water were de¬termined 6.55, 0.79, 16.23, 3.41, 4.49, and 49.33µg/L, respectively. The average and even maxi¬mum concentrations of heavy metals in the irrigation water at the studied area were less than toxicity threshold limits of agricultural water. Conclusion: Currently, not using of surface runoff and industrial wastewater as irrigation water by farmers indicates that the controlling efforts by authorities have been effective in the area. Water used for irrigation of the farms and groundwater of the studied area are not polluted with heavy metals and there is no risk from this viewpoint in the region. PMID:24688935

Taghipour, Hassan; Mosaferi, Mohammad; Pourakbar, Mojtaba; Armanfar, Feridoun

2012-01-01

312

Heavy metal analysis in commercial Spirulina products for human consumption.  

PubMed

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

2013-10-01

313

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

314

Smart responsive microcapsules capable of recognizing heavy metal ions.  

PubMed

Smart responsive microcapsules capable of recognizing heavy metal ions are successfully prepared with oil-in-water-in-oil double emulsions as templates for polymerization in this study. The microcapsules are featured with thin poly(N-isopropylacrylamide-co-benzo-18-crown-6-acrylamide) (P(NIPAM-co-BCAm)) membranes, and they can selectively recognize special heavy metal ions such as barium(II) or lead(II) ions very well due to the "host-guest" complexation between the BCAm receptors and barium(II) or lead(II) ions. The stable BCAm/Ba(2+) or BCAm/Pb(2+) complexes in the P(NIPAM-co-BCAm) membrane cause a positive shift of the volume phase transition temperature of the crosslinked P(NIPAM-co-BCAm) hydrogel to a higher temperature, and the repulsion among the charged BCAm/Ba(2+) or BCAm/Pb(2+) complexes and the osmotic pressure within the P(NIPAM-co-BCAm) membranes result in the swelling of microcapsules. Induced by recognizing barium(II) or lead(II) ions, the prepared microcapsules with P(NIPAM-co-BCAm) membranes exhibit isothermal and significant swelling not only in outer and inner diameters but also in the membrane thickness. The proposed microcapsules in this study are highly attractive for developing smart sensors and/or carriers for detection and/or elimination of heavy metal ions. PMID:20656104

Pi, Shuo-Wei; Ju, Xiao-Jie; Wu, Han-Guang; Xie, Rui; Chu, Liang-Yin

2010-09-15

315

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

316

Bacterial metal-resistance proteins and their use in biosensors for the detection of bioavailable heavy metals  

Microsoft Academic Search

We have expressed and purified metal-resistance and metal regulatory proteins from the bacterial determinants of resistance to heavy metals and utilised these in the development of biosensors for heavy metals. Both the metallothionein from the cyanobacterium Synechococcus PCC 7942 and the MerR regulatory protein from transposon Tn501 allow the detection of non-specific metal binding down to 10?15 M concentrations of

Ibolya Bontidean; Jon R Lloyd; Jon L Hobman; Jon R Wilson; Elisabeth Csöregi; Bo Mattiasson; Nigel L Brown

2000-01-01

317

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

318

Genotoxic effects of heavy metals: comparative investigation with plant bioassays.  

PubMed

The potential use of micronucleus assays in plants for the detection of genotoxic effects of heavy-metal ions was investigated. Three different plant systems were comparatively investigated in micronucleus tests with Tradescantia pollen mother cells (Trad MCN) and micronucleus tests with meristematic root tip cells of Allium cepa and Vicia faba (Allium/ Vicia MCN). As3+, Pb2+, Cd2+, Zn2+ caused a dose-dependent increase of MCN frequencies in all three test systems. Cu2+ gave consistently negative responses in all three tests; Zn2+ caused only a moderate, statistically not significant increase of MCN frequencies in Vicia. The ranking of genotoxic potencies in all three tests was in the descending order: As3+ > Pb2+ > Cd2+ > Zn2+ Cu2+. In experiments with Tradescantia, induction of MCN was observed in a concentration range between 1 and 10 mM, whereas in tests with root tip cells, higher concentrations (10-1,000 mM) were required to show significant effects. Further increase of the exposure levels caused toxic effects (reduction of root growth), cell division delays, and a decrease of MCN frequencies. Comparisons by linear regression analyses indicated that the sensitivity of the three bioassays for heavy metals decreases in the order: Trad MCN > Vicia root MCN > Allium root MCN. In further experimental series, a soil sample which contained high concentrations of the five metals and a control soil were investigated. Aqueous soil extracts induced only weak effects in Trad MCN tests and no effects in the root tip assays, whereas cultivation of the plants in the soils resulted in a pronounced induction of MCN in the Tradescantia system and moderate effects in Vicia and Allium. In conclusion, the results of the study indicate that the Trad MCN assay detects the genotoxic effects of heavy metals and can be used for biomonitoring metal-contaminated soils. PMID:9544197

Steinkellner, H; Mun-Sik, K; Helma, C; Ecker, S; Ma, T H; Horak, O; Kundi, M; Knasmüller, S

1998-01-01

319

Analysis of heavy oils: Method development and application to Cerro Negro heavy petroleum: Topical report. [Metal content in Cerro Negro heavy petroleum  

Microsoft Academic Search

Nickel, vanadium, and iron were determined in distilled and chromatographically separated fractions from Cerro Negro heavy petroleum. Corresponding data were also obtained on two samples of Wilmington, California, heavy crude and one Mayan, Mexico, heavy oil for comparison. For the Cerro Negro crude, the ratio of porphyrinic to nonporphyrinic forms of metals was also determined on selected fractions using visible

C. D. Pearson; J. A. Green; J. B. Green

1988-01-01

320

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

321

Concentration and annual accumulation values of heavy metals in lake sediments: Their significance in studies of the history of heavy metal pollution  

Microsoft Academic Search

The first part of the paper discusses the significance of using either concentration or accumulation values for expressing the results of investigations of lake sediment cores aimed at studying the history of heavy metal pollution. Neither the values for heavy metal concentration in the lake sediment, whether expressed per gram dry sediment or per gram soluble (organic) sediment, nor the

Ingemar Renberg

1986-01-01

322

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

323

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

324

MELIMEX, an experimental heavy metal pollution study: Behaviour of heavy metals in an aquatic food chain  

Microsoft Academic Search

Phytoplankton, periphyton and zooplankton samples, chironomid andSialis sp. larvae, and fry of trout and bream collected from unpolluted and artificially metal-polluted limno-corrals were analyzed\\u000a for mercury, copper, cadmium, zinc and lead. The results indicate that these metals are not accumulated through the food chain\\u000a and suggest that increased metal concentrations in the environment favor the growth of phytoplankton organisms with

René Gächter; Wolfgang Geiger

1979-01-01

325

MELIMEX, an experimental heavy metal pollution study: Effects of increased heavy metal loads on phytoplankton communities  

Microsoft Academic Search

Long-term impacts of increased metal loading (Hg, Cu, Cd, Zn and Pb) on phytoplankton communities of large limno-corrals (diameter\\u000a 12 m, depth 10 m) were studied. Increased metal concentrations initially lowered phytoplankton biomass, as well as species\\u000a number and photosynthetic activity of phytoplankton. They caused changes in metal speciation and shifts in phytoplankton community\\u000a structure, favoring less susceptible species. Although

René Gächter; Antonín Máreš

1979-01-01

326

Effects of some trace heavy metals on Poecilia reticulata (Peters).  

PubMed

Three trace heavy metals viz., nickel, copper and zinc were studied for their toxic action against Poecilia retriculata (Peters). Among these, copper was found to be most active followed by zinc and nickel. Accumulations of these metals as well as behavioural studies were carried out after exposing fish to sub-lethal concentration of LC20. It was found that the highest quantity of nickel was accumulated in the fish body followed by zinc and copper. After exposure to sub-lethal concentration of metals some behavioural changes in fish were observed due to stress, such as mucus like secretion over gills, excessive excretion, anoretic condition and increased distance between gills and operculum. In all the cases fin movement was observed. Role and use of such changes as biological indicators or as biological early warning system in water quality assessment has been discussed. PMID:11500020

Khunyakari, R P; Tare, V; Sharma, R N

2001-04-01

327

Saccharomyces cerevisiae and Neurospora crassa contain heavy metal sequestering phytochelatin.  

PubMed

In fungi, cellular resistance to heavy metal cytotoxicity is mediated either by binding of metal ions to proteins of the metallothionein type or by chelation to phytochelatin-peptides of the general formula (gamma-Glu-Cys)n-Gly. Hitherto, only one fungus, Candida glabrata has been shown to contain both metal inactivating systems. Here we show by unambiguous FAB-MS analysis that both a metallothionein-free mutant of Saccharomyces cerevisiae as well as a wildtype strain synthesize phytochelatin (PC2) upon exposure to 250 microM Cd2+ ions. The presence of Zn and/or Cu ions in the nutrient broth also induces PC2 synthesis in this organism. By 109Cd exchange and subsequent monobromobimane fluorescence HPLC, it could be shown that the presence of Cd2+ in the growth medium also induces phytochelatin synthesis in Neurospora crassa, which contains metallothioneins. PMID:1534214

Kneer, R; Kutchan, T M; Hochberger, A; Zenk, M H

1992-01-01

328

Aligned nanogold assisted one step sensing and removal of heavy metal ions.  

PubMed

We depict a novel strategy exploiting the chemistry of metal ion adsorption for detection and sequestration of toxic heavy metal from processed water using gold nanoparticles capped with 4-aminothiophenol. The interaction between 4-aminothiophenol capped gold nanoparticles and heavy metal ions was studied as a function of time and concentration using TEM, HRTEM, SEM, EDS, and I-V characterization. Experiments confirmed that pH is one of the crucial controlling parameters. Adsorption capacity was monitored using AAS, UV-vis spectroscopy and I-V measurement. In the absence of any alloy formation between Au and heavy metal ions, the desorption of the heavy metal ions from 4-aminothiophenol capped gold nanoparticles surface by pH modulation serves as a mean of collection of heavy metal ions. Experiments revealed that the concentration of heavy metal ions in processed water after adsorption is below the maximum permissible limit set by the WHO. PMID:21851947

Chauhan, Neha; Gupta, Shweta; Singh, Nahar; Singh, Sukhvir; Islam, Saikh S; Sood, Kedar N; Pasricha, Renu

2011-11-01

329

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

330

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

2013-05-20

331

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

332

Chelant extraction of heavy metals from contaminated soils.  

PubMed

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 approximately 60% sand, 30% silt, and 10% clay. Sequential extractions were performed on the 'as-received' soils (worst case and representative) to determine the speciation of the metal forms. The technique speciates the heavy metal distribution into an easily extractable (exchangeable) form, carbonates, reducible oxides, organically-bound, and residual forms. The results indicated that most of the metals are in forms that are amenable to soil washing (i.e. exchangeable+carbonate+reducible oxides). The metals Cu, Pb, Zn, and Cr have greater than 70% of their distribution in forms amenable to soil washing techniques, while Cd, Mn, and Fe are somewhat less amenable to soil washing using chelant extraction. However, the concentrations of Cd and Mn are low in the contaminated soil. From the batch chelant extraction studies, ethylenediaminetetraacetic acid (EDTA), citric acid, and nitrilotriacetic acid (NTA) were all effective in removing copper, lead, and zinc from the J-Field soils. Due to NTA being a Class II carcinogen, it is not recommended for use in remediating contaminated soils. EDTA and citric acid appear to offer the greatest potential as chelating agents to use in soil washing the Aberdeen Proving Ground soils. The other chelating agents studied (gluconate, oxalate, Citranox, ammonium acetate, and phosphoric acid, along with pH-adjusted water) were generally ineffective in mobilizing the heavy metals from the soils. The chelant solution removes the heavy metals (Cd, Cu, Pb, Zn, Fe, Cr, As, and Hg) simultaneously. Using a multiple-stage batch extraction, the soil was successfully treated passing both the Toxicity Characteristics Leaching Procedure (TCLP) and EPA Total Extractable Metal Limit. The final residual Pb concentration was about 300 mg/kg, with a corresponding TCLP of 1.5 mg/l. Removal of the exchangeable and carbonate fractions for Cu and Zn was achieved during the first extraction stage, whereas it required two extraction stages for the same fractions for Pb. Removal of Pb, Cu, and Zn present as exchangeable, carbonates, and reducible oxides occurred between the fourth- and fifth-stage extractions. The overall removal of copper, lead, and zinc from the multiple-stage washing were 98.9%, 98.9%, and 97.2%, respectively. The concentration and operating conditions for the soil washing extractions were not necessarily optimized. If the conditions had been optimized and using a more representative Pb concentration (approximately 12000 mg/kg), it is likely that the TCLP and residual heavy metal soil concentrations could be achieved within two to three extractions. The results indicate that the J-Field contaminated soils can be successfully treated using a soil washing technique. PMID:10379036

Peters, R W

1999-04-23

333

Effect of heavy metal-solubilizing microorganisms on zinc and cadmium extractions from heavy metal contaminated soil with Tricholoma lobynsis.  

PubMed

The macrofungus, Tricholoma lobynsis, was chosen to remedy Zn-Cd-Pb contaminated soil. To enhance its metal-extracting efficiency, two heavy metal resistant microbes M6 and K1 were applied owing to their excellent abilities to solubilize heavy metal salts. The two isolated microbial strains could also produce indole acetic acid (IAA), siderophore and solubilize inorganic phosphate, but neither of them showed 1-aminocyclopropane-1-carboxylate deaminase activity. The strains M6 and K1 were identified as Serratia marcescens and Rhodotorula mucilaginosa based on 16S rDNA and ITS sequence analysis respectively. Pot experiment showed that spraying to T. lobynsis-inoculated soil with M6 and K1 respectively could increase total Cd accumulations of this mushroom by 216 and 61%, and Zn by 153 and 49% compared to the uninoculated control. Pb accumulation however, was too low (<1 mg kg(-1)) to be determined. The results illustrated that special microbes and macrofungi can work together to remedy polluted soil as plant and plant growth promoting microbes do, probably because of excellent metal-accumulating abilities of macrofungi and IAA-siderophore production, phosphate solubilization abilities of the assisted-microbes. This kind of macrofungi-microbe interaction can be developed into a novel bioremediation strategy. PMID:22806805

Ji, Ling-yun; Zhang, Wei-wei; Yu, Dong; Cao, Yan-ru; Xu, Heng

2012-01-01

334

Monitoring of metallic micronutrients and heavy metals in herbs, spices and medicinal plants from Austria  

Microsoft Academic Search

Medicinal, aromatic and spice plants grown in different regions of Austria were monitored as to their Cd, Cu, Fe, Mn, Pb and Zn contents. Since the plants were grown under common field conditions, the essential elements were within the usual ranges for plant material. The contamination level with the toxic heavy metals, Pb and Cd, can be classified as normally

Remigius Chizzola; Hanneliese Michitsch; Chlodwig Franz

2003-01-01

335

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

336

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

337

Seed Germination of Some Medicinal and Aromatic Plants in Heavy Metal Environment  

Microsoft Academic Search

The effect of heavy metals (Cd, Cu, Pb, Zn) on seed germination and root growth in Pimpinella anisum L. (anise), Carum carvi L. (caraway), and Foeniculum vulgare L. (fennel) was evaluated on randomly selected samples of 50 seeds in three replicates from each of the plant species. Heavy metal test solutions were prepared from each metal at two concentrations, the

E. A. Jeliazkova; L. E. Craker

2003-01-01

338

Analysis of Heavy Metal Content in Canabis Leaf and Seed Cultivated in Southern Part of Nigeria  

Microsoft Academic Search

The distribution of heavy metals content in cannabis leaf and seed were assayed \\/ carried, using an atomic absorption spectrometers model Perkin Elmer 3110. The heavy metals determined in bot h samples mean arsenic, cadmium, chromium, iron, nickel, lead mercury and manganese. The results obtained revealed that metal levels in cannabis leaf exceeded those of cannabis seed except in manganese,

2005-01-01

339

Assessment of heavy metal pollution in urban topsoils from the metropolitan area of Mexico City  

Microsoft Academic Search

This study reports the degree of heavy metal pollution (Cr, Cu, Ni, Pb, Zn and V) in 135 urban topsoil samples from the metropolitan area of Mexico City. Pollution indices (PI) were calculated to identify the metal accumulation with respect to the background values. The levels of heavy metals in the analyzed samples show a wide range of variation. Lead,

O. Morton-Bermea; E. Hernández-Álvarez; G. González-Hernández; F. Romero; R. Lozano; L. E. Beramendi-Orosco

2009-01-01

340

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

341

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...

342

Heavy metal levels in two fish species Leuciscus cephalus and Lepomis gibbosus  

Microsoft Academic Search

The concentrations of heavy metals (Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn) were measured in muscle, gill and liver of two fish species (Leuciscus cephalus and Lepomis gibbosus) caught from Saricay, South-West Anatolia. Levels of metals varied depending on different tissues in species. The mean concentrations (?gg?1 wet weight) of heavy metals in tissues of Leucis cephalus were as

Fevzi Y?lmaz; Nedim Özdemir; Ahmet Demirak; A. Levent Tuna

2007-01-01

343

Heavy Metals contamination in two bioluminescent bays of Puerto Rico Yadira Soto Viruet  

E-print Network

1 Heavy Metals contamination in two bioluminescent bays of Puerto Rico Yadira Soto Viruet #802 characteristics. The main purpose of this research was to evaluate the presence of heavy metals terminals and chemical, metal and paper facilities) (Hostetteler, 1999; van Geen and Louma, 1999). The earth

Gilbes, Fernando

344

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

345

The German heavy metal survey by means of mosses.  

PubMed

This is the first attempt to determine pollution with metals throughout the Federal Republic of Germany by analysing moss samples. Samples of Pleurozium schreberi, Scleropodium purum, Hypnum cupessiforme and Hylocomium splendens were collected at 593 sites and analysed by ICP-AES and AAS for the elements As, Cd, Cr, Cu, Fe, Ni, Pb, V and Zn. Citrus leaves and pine needles were used as reference materials to ensure the quality of the results. In many cases it was possible to trace the areas affected by known sources of heavy-metal emissions in addition to isolated local increases in the values. The moss monitoring programme showed up the highly industrialized and urban locations such as the Ruhr, parts of the Saarland and Baden-Wurttemberg and large areas of eastern Germany. Lower levels of many elements were found in wide stretches of Lower Saxony and Bavaria. The results largely reflect the pollution patterns found in these areas. On the other hand, expected correlations between the effects of traffic (e.g. Pb) and concentrations in moss could not be demonstrated with certainty. The element data yielded by this project are Germany's contribution to the European project 'Atmospheric Heavy Metal Deposition in Europe -- Estimations based on Moss Analysis'. PMID:8854944

Markert, B; Herpin, U; Siewers, U; Berlekamp, J; Lieth, H

1996-04-01

346

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

347

Simultaneous determination of heavy metals in cosmetic products.  

PubMed

An extremely small amount of several heavy metals have been detected in cosmetic products as impurities, which can cause skin allergies through percutaneous adsorption on the skin. We present here a fast, accurate, and highly sensitive method for simultaneous determination of Pb2+, Fe2+, Cu2+, Ni2+, Zn2+, Co2+, Cd2+ and Mn2+ in coloring agents and cosmetic products, to be evaluated by ion chromatography. All of these metals are well separated through a bifunctional ion-exchange column (IonPac CS5A) and detected by post-column reaction and spectrophotometric detection. The calibration graphs are linear (r2 > 0.999), in the range 0.1-1000 microg/ml. Detection limits for a 200-microl sample solution are at the mug/l level, which is sufficient for judging whether the product is safe or not. The relative standard deviations (RSDs) of the retention time and the peak area are less than 0.21% and 1.24%, respectively. The recovery rates are 97-104%. The result shows that the proposed determination method is more sensitive, more accurate, and faster than current methods such as HPLC, ICP-MS and Flame-AAS. The new method was applied to analyze the amount of heavy metals contained in 22 cosmetic products and 11 coloring agents. PMID:18841308

Lee, So-Mi; Jeong, Hye-Jin; Chang, Ih Seop

2008-01-01

348

Biomonitoring of heavy metals in fish from the Danube River.  

PubMed

The Croatian part of the Danube River extends over 188 km and comprises 58 % of the country's overall area used for commercial freshwater fishing. To date, the heavy metal contamination of fish in the Croatian part of the Danube has not been studied. The main purpose of this study was to determine heavy metal levels in muscle tissue of sampled fish species and to analyze the measured values according to feeding habits of particular groups. Lead ranged from 0.015 ?g(-1) dry weight in planktivorous to 0.039 ?g(-1) dry weight in herbivorous fish, cadmium from 0.013 ?g(-1) dry weight in herbivorous to 0.018 ?g(-1) dry weight in piscivorous fish, mercury from 0.191 ?g(-1) dry weight in omnivorous to 0.441 ?g(-1) dry weight in planktivorous fish and arsenic from 0.018 ?g(-1) dry weight in planktivorous to 0.039 ?g(-1) dry weight in omnivorous fish. Among the analyzed metals in muscle tissue of sampled fish, only mercury exceeded the maximal level (0.5 mg kg(-1)) permitted according to the national and EU regulations determining maximum levels for certain contaminants in foodstuffs, indicating a hazard for consumers of fish from the Danube River. PMID:22527460

Zrn?i?, Snježana; Orai?, Dražen; ?aleta, Marko; Mihaljevi?, Željko; Zanella, Davor; Bilandži?, Nina

2013-02-01

349

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

350

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

351

Hybrid process for heavy metal removal from wastewater sludge.  

PubMed

Bioleaching processes have been demonstrated to be effective technologies in removing heavy metals from wastewater sludge, but long hydraulic retention times are typically required to operate these bioprocesses. A hybrid process (coupling biological and chemical processes) has been explored in laboratory pilot-scale experiments for heavy metals (cadmium [Cd], copper [Cu], chromium [Cr], and zinc [Zn]) removal from three types of sludge (primary sludge, secondary activated sludge, and a mixture of primary and secondary sludge). The hybrid process consisted of producing a concentrate ferric ion solution followed by chemical treatment of sludges. Ferric iron solution was produced biologically via oxidation of ferrous iron by A. ferrooxidans in a continuous-flow stirred tank (5.2 L) reactor (CSTR). Wastewater sludge filtrate (WSF) containing nutrients (phosphorus and nitrogen) has been used as culture media to support the growth and activity of indigenous iron-oxidizing bacteria. Results showed that total organic carbon (TOC) concentrations of the culture media in excess of 235 mg/L were found to be inhibitory to bacterial growth. The oxidation rate increased as ferrous iron concentrations ranged from 10 to 40 g Fe2+/L. The percentage of ferrous iron (Fe2+) oxidized to ferric iron (Fe3+) increased as the hydraulic retention time (HRT) increased from 12 to 48 h. Successful and complete Fe2+ oxidation was recorded at a HRT of 48 h using 10 g Fe2+/L. Subsequently, ferric ion solution produced by A. ferrooxidans in sludge filtrate was used to solubilize heavy metals contained in wastewater sludge. The best solubilization was obtained with a mixture of primary and secondary sludge, demonstrating a removal efficiency of 63, 71, 49, and 80% for Cd, Cu, Cr, and Zn, respectively. PMID:16121505

Drogui, Patrick; Blais, Jean-François; Mercier, Guy

2005-01-01

352

[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

353

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

354

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

355

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

356

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

357

Using semivariogram scaled to the sample design of heavy metals  

NASA Astrophysics Data System (ADS)

The "sampling intensity" issue is of important application to precision agriculture. About 80%-85 % of the total error in precision in agriculture results from the field sampling preceding the application of fertilizers and corrective practices. The spatial sampling design used to characterize the spatial variability of soil attributes is crucial to science studies. The sample planning for interpolation of a regionalized variable may use several criteria, which could be best selected from the estimated semivariogram from a previously established grid. The objective of this study was to evaluate the use of the semivariogram scaled to improve the sample design of heavy metals in an experimental plot. The study area surface is 6 ha and is located at Castro Ribeiras de Lea, Lugo, Spain. The geographical coordinates of the study area are: latitude 43° 09 '49''N and longitude 7° 29' 47''W, with average elevation of 410 m and average slope of 2 %. The mean annual temperature is 11.2 °C and mean annual rainfall is 930 mm (data 1961-1990). The soil is classified with Cambisol and the parent material are sediments from tertiary and quaternary. Heavy metals were initially sampled at 40 points randomly distributed in the study area. The heavy metals analyzed in this study were: Pb, Cd, Cu and Ni. Data were initially analyzed using descriptive statistics and geostatistical tools. The scaled semivariogram was built with the aim of setting a single theoretical semivariogram all elements studied. Subsequently, the software SANOS was used to determine the sampling optimization of new sampling points of the heavy metals. The spatial variability analysis of the studied elements using the scaled semivariogram showed the existence of a relationship between the spatial variability of these elements. The gaussian model was adjusted for Pb, Cd and Ni, and spherical models for the Cu element. The semivariogram scaled theoretical adjusted to elements in four study was Gaussian, with a value range of 70 m, and this value range intermediate values found for the individual semivariograms. The scaled semivariogram and programs of simulation of sampling points based on the parameters of the semivariogram can be used to assist soil management.

Medeiros Bezerra, Joel; Machado Siqueira, Glécio; Dafonte Dafonte, Jorge; Vidal Vazquez, Eva; Paz González, Antonio

2013-04-01

358

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

359

Heavy Metal Content of Potato Chips and Biscuits from Nagpur City, India  

Microsoft Academic Search

Heavy metals composition of foods is of immense interest because of its essential or toxic nature. In view of this, we determined\\u000a concentrations of select heavy metals from food items such as, potato chips and biscuits that were obtained from Nagpur City,\\u000a India. The present study revealed preferred digestion method for different heavy metal recovery. The accumulation trend for\\u000a Potato

Meetu Gopalani; Mrunalini Shahare; Dilip S. Ramteke; Satish R. Wate

2007-01-01

360

Criteria of the technogenic nature of heavy metals and metalloids in soils: A review of publications  

Microsoft Academic Search

Both routine statistical methods (the compliance of the heavy metal content with the exponent or ruling out abnormally high\\u000a values of heavy metal concentrations in the Gaussian distribution) and new geostatistics based approaches are used as the\\u000a criteria of the technogenic nature of heavy metals. Methods are being developed that take into consideration the marker element\\u000a content (Al) in soil

Yu. N. Vodyanitskii; Dokuchaev Soil

2009-01-01

361

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

362

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

363

Molecular Mechanisms and Genetic Basis of Heavy Metal Toxicity and Tolerance in Plants  

Microsoft Academic Search

\\u000a Heavy metal pollutants are mainly derived from growing number of anthropogenic sources. As the environmental pollution with\\u000a heavy metals increases, some new technologies are being developed, one of these being phytoremediation. Hyperaccumulator plant\\u000a varieties can be achieved by using methods of genetic engineering. An uptake of excessive amounts of heavy metals by plants\\u000a from soil solution leads to range of

Nand Lal

364

Biomimetic metal-sorbing vesicles for continuous extraction of heavy metal ions from dilute solution  

SciTech Connect

Biomimetic vesicle media which can selectivity extract and concentrate heavy metals (e.g., Pb{sup 2+}) from dilute solutions of 5 ppm and less have been prepared. At a concentration of only 1% 2/v, these non-covalently assembled, unilamellar, surfactant vesicles provide approximately 1,000m{sup 2} of exposed membrane surface area per liter of suspension which gives rise to very rapid rates of metal ion extraction. To facilitate the selective transport of heavy metal ions through the ion impermeable vesicle wall, the vesicles are doped with lipophilic ionophores, both natural and synthetic. In addition, the metal chelating agent, nitrolotriacetate, is encapsulated in the aqueous vesicle core to provide the driving force for metal ion uptake and concentration. Concentration factors in excess of 1000 fold have been observed. Metal-sorbing surfactant vesicles measuring approximately 100 nm in diameter are stable and have been tested in a bench-scale metal ion extraction process where the vesicles are recircled continuously through a hollow-fiber ultrafiltration cartridge.

Monbouquette, H.G.; Chang, D.; Walsh, A.J.; van Zanten, J.H. [Univ. of California, Los Angeles, CA (United States)

1993-12-31

365

Genetic manipulation of a cyanobacterium for heavy metal detoxivication  

SciTech Connect

Increasing heavy metal contamination of soil and water has produced a need for economical and effective methods to reduce toxic buildup of these materials. Biological systems use metallothionein proteins to sequester such metals as Cu, Cd, and Zn. Studies are underway to genetically engineer a cyanobacteria strain with increased ability for metallothionein production and increased sequestration capacity. Cyanobacteria require only sunlight and CO{sub 2}. Vector constructs are being developed in a naturally competent, unicellular cyanobacterium Anacystis nidulans R2. Closed copies of a yeast copper metallothionein gene have been inserted into a cyanobacterial shuttle vector as well as a vector designed for genomic integration. Transformation studies have produced recombinant cyanobacteria from both of these systems, and work is currently underway to assess the organism`s ability to withstand increasing Cu, Cd, and Zn concentrations.

McCormick, P.; Cannon, G.; Heinhorst, S.

1995-12-31

366

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

367

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

368

Nonequilibrium transport of heavy metals in soils and its influence on soil remediation.  

E-print Network

??With increasing concern about soil and groundwater contamination, research on contaminant transport modeling and remediation technology has grown rapidly. Nonequilibrium transport of heavy metals resulting… (more)

Tsang, Chiu Wa

2006-01-01

369

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

370

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

371

Sources of heavy metals in urban wastewater in Stockholm.  

PubMed

The sources of heavy metals to a wastewater treatment plant was investigated. Sources can be actual goods, e.g. runoff from roofs, wear of tires, food, or activities, e.g. large enterprises, car washes. The sources were identified by knowing the metals content in various goods and the emissions from goods to sewage or stormwater. The sources of sewage water and stormwater were categorized to enable comparison with other research and measurements. The categories were households, drainage water, businesses, pipe sediment (all transported in sewage water), atmospheric deposition, traffic, building materials and pipe sediment (transported in stormwater). Results show that it was possible to track the sources of heavy metals for some metals such as Cu and Zn (110 and 100% found, respectively) as well as Ni and Hg (70% found). Other metals sources are still poorly understood or underestimated (Cd 60%, Pb 50%, Cr 20% known). The largest sources of Cu were tap water and roofs. For Zn the largest sources were galvanized material and car washes. In the case of Ni, the largest sources were chemicals used in the WTP and drinking water itself. And finally, for Hg the most dominant emission source was the amalgam in teeth. For Pb, Cr and Cd, where sources were more poorly understood, the largest contributors for all were car washes. Estimated results of sources from this study were compared with previously done measurements. The comparison shows that measured contribution from households is higher than that estimated (except Hg), leading to the conclusion that the sources of sewage water from households are still poorly understood or that known sources are underestimated. In the case of stormwater, the estimated contributions are rather well in agreement with measured contributions, although uncertainties are large for both estimations and measurements. Existing pipe sediments in the plumbing system, which release Hg and Pb, could be one explanation for the missing amount of these metals. Large enterprises were found to make a very small contribution, 4% or less for all metals studied. Smaller enterprises (with the exception of car washes) have been shown to make a small contribution in another city; the contribution in this case study is still unknown. PMID:12449334

Sörme, L; Lagerkvist, R

2002-10-21

372

Chelation: harnessing and enhancing heavy metal detoxification--a review.  

PubMed

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

373

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

374

[Immobilization of heavy metal Pb2+ with geopolymer].  

PubMed

A series of geopolymers were synthesized by mixing metakaolinite, water glass, sodium hydroxide and water, and the lead ion solidification experiments were performed with the geopolymer. Then, the immobilization efficiency was characterized by monitoring the leaching concentration and compressive strength of solidified products. Additionally, the structure and properties of the solidified products were studied by X-ray diffraction (XRD), scan electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Furthermore, based on the analysis of immobilization efficiency, microstructure and mineral structure, the difference between geopolymer and cement on the performance of immobilizing heavy metals was discussed. The results of lead ion immobilization experiments showed that over 99.7% of heavy metal was captured by the geopolymer as the doping concentration of lead ion was less than 3%. Meanwhile, the compressive strength of the solidified product ranged from 40 MPa to 50 MPa. Furthermore, by using the same Pb2+ concentration, the geopolymer showed higher compressive strength and lower leaching concentration compared to the cement. Because lead ion participated in constitution of structure of geopolymer, or Pb2+ was adsorbed by the aluminium ions on the geopolymeric skeleton and held in geopolymer. However, cement mainly solidified lead ion by physical encapsulation and adsorption mechanism. Therefore, both from the compressive strength and leaching concentration and from the microstructure characterization as well as the mechanism of the geopolymerization reaction, the geopolymer has more advantages in immobilizing Pb2+ than the cement. PMID:21780604

Jin, Man-tong; Jin, Zan-fang; Huang, Cai-ju

2011-05-01

375

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

376

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

377

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

378

Mussel Shell Evaluation as Bioindicator For Heavy Metals  

NASA Astrophysics Data System (ADS)

Recently, in Brazil, it has appeared a new and unusual "plague" in lazer and commercial fishing. It is caused by the parasitic larval phase of certain native bivalve mollusks of fresh water known as "Naiades" and its involves the presence of big bivalve of fresh water, mainly Anodontites trapesialis, in the tanks and dams of the fish creation. These bivalve mollusks belong to the Unionoida Order, Mycetopodidae Family. The objective of the present work was to analyze the shells of these mollusks to verify the possibility of use as bioindicators for heavy metals in freshwater. The mollusks shells were collected in a commercial fishing at Londrina-PR. A qualitative analysis was made to determine the chemical composition of the shells and verify a possible correlation with existent heavy metals in the aquatic environment. In the inner part of the shells were identified the elements Ca, P, Fe, Mn and Sr and in the outer part were identified Ca, P, Fe, Mn, Sr and Cu. The Ca ratio of the outer part by inner part of the analyzed shells is around of 1, as expected, because Ca is the main compound of mollusks shells. The ratio of P, Fe, Mn, and Sr to the Ca were constant in all analyzed shells, being close to 0.015. The ratio Cu/Ca varied among the shells, showing that this mollusk is sensitive to concentration of this element in the aquatic environment.

Andrello, Avacir Casanova; Lopes, Fábio; Galvão, Tiago Dutra

2010-05-01

379

Perturbations in nucleosome structure from heavy metal association  

PubMed Central

Heavy metals have the potential to engage in strong bonding interactions and can thus function in essential as well as toxic or therapeutic capacities. We conducted crystallographic analyses of heavy cation binding to the nucleosome core particle and found that Co2+ and Ni2+ preferentially associate with the DNA major groove, in a sequence- and conformation-dependent manner. Conversely, Rb+ and Cs+ are found to bind only opportunistically to minor groove elements of the DNA, in particular at narrow AT dinucleotide sites. Furthermore, relative to Mn2+ the aggressive coordination of Co2+ and Ni2+ to guanine bases is observed to induce a shift in histone–DNA register around the nucleosome center by stabilizing DNA stretching over one region accompanied by expulsion of two bases at an opposing location. These ‘softer’ transition metals also associate with multiple histone protein sites, including inter-nucleosomal cross-linking, and display a proclivity for coordination to histidine. Sustained binding and the ability to induce structural perturbations at specific locations in the nucleosome may contribute to genetic and epigenetic mechanisms of carcinogenesis mediated by Co2+ and Ni2+. PMID:20494975

Mohideen, Kareem; Muhammad, Reyhan; Davey, Curt A.

2010-01-01

380

Heavy meals in urban roadside soils, part 1: effect of particle size fractions on heavy metals partitioning  

NASA Astrophysics Data System (ADS)

Urban roadside soils are important environmental media for assessing heavy metal concentrations in urban environment. However, among other things, heavy metal concentrations are controlled by soil particle grain size fractions. In this study, two roadside sites were chosen within the city of Xuzhou (China) to reflect differences in land use. Bulk soil samples were collected and then divided by particle diameter into five physical size fractions, 500-250, 250-125, 125-74, 74-45, < 45 ?m. Concentrations of metals (Ti, Cr, Al, Ga, Pb, Ba, Cd, Co, Cu, Mn, Ni, V, Zn, Mo, As, Sb, Se, Hg, Bi, Ag) were determined for each individual fraction. These metals could be roughly classified into two groups: anthropogenic element (Pb, Ba, Cd, Cu, Zn, Mo, As, Sb, Se, Hg, Bi, Ag) and lithophile element (Ti, Cr, Al, Ga, Co, Mn, Ni, V) in terms of values of enrichment factor. As expected, higher concentrations of anthropogenic heavy metals (Cu, Zn, Mo, As, Hg, Bi, Ag) are observed in the finest particle grain size fraction (i.e. < 45 ?m). However, heavy metals Se, Sb and Ba behave independently of selected grain size fractions. From the viewpoint of mass loading, more than 30% of the concentrations for all anthropogenic heavy metals are contributed by the particle grain size fractions of 45-74 ?m at site 1 and more than 70% of the concentrations for all heavy metals are contributed by the particle grain size fractions of 45-74 and 74-125 ?m at site 2. These results are important for transport of soil-bound heavy metals and pollution control by various remedial options.

Wang, Xue-Song; Qin, Yong; Chen, Yong-Kang

2006-08-01

381

TREATMENT OF HEAVY METALS IN STORMWATER RUNOFF USING RETENTION PONDS AND CONSTRUCTED WETLANDS  

EPA Science Inventory

Urban stormwater runoff is a significant source of suspended sediments and associated contaminants, including heavy metals, to receiving waterways. These metals are either dissolved or bound to particulates (coarse >75 µm; fine particulates ...

382

TREATMENT OF HEAVY METALS IN STORMWATER USING WET POND AND WETLAND MESOCOSMS  

EPA Science Inventory

Urban stormwater runoff is a significant source of suspended sediments and associated contaminants, including heavy metals, to receiving waterways. These metals are either dissolved or bound to particulates (coarse - >75 µm; fine particulates - ...

383

DEVELOPMENT OF LOCOMOTOR ACTIVITY OF RAT PUPS EXPOSED TO HEAVY METALS  

EPA Science Inventory

Cadmium (Cd), triethyltin (TET), and trimethyltin (TMT) are heavy metals which are neurotoxic to developing animals. In the present experiment, preweaning assessment of locomotor activity was used to detect and differentiate between the developmental toxicity of these metals. On ...

384

DRAFT The Common Vernacular of Power Relations in Heavy Metal and Christian Fundamentalist Performances  

Microsoft Academic Search

Wittgenstein's comment that what can be shown cannot be said has a special resonance with visual representations of power in both Heavy Metal and Fundamentalist Christian communities. Performances at metal shows, and performances of \\

Christine A. James

385

Analysis of heavy metal sources in soil using kriging interpolation on principal components.  

PubMed

Anniston, Alabama has a long history of operation of foundries and other heavy industry. We assessed the extent of heavy metal contamination in soils by determining the concentrations of 11 heavy metals (Pb, As, Cd, Cr, Co, Cu, Mn, Hg, Ni, V, and Zn) based on 2046 soil samples collected from 595 industrial and residential sites. Principal Component Analysis (PCA) was adopted to characterize the distribution of heavy metals in soil in this region. In addition, a geostatistical technique (kriging) was used to create regional distribution maps for the interpolation of nonpoint sources of heavy metal contamination using geographical information system (GIS) techniques. There were significant differences found between sampling zones in the concentrations of heavy metals, with the exception of the levels of Ni. Three main components explaining the heavy metal variability in soils were identified. The results suggest that Pb, Cd, Cu, and Zn were associated with anthropogenic activities, such as the operations of some foundries and major railroads, which released these heavy metals, whereas the presence of Co, Mn, and V were controlled by natural sources, such as soil texture, pedogenesis, and soil hydrology. In general terms, the soil levels of heavy metals analyzed in this study were higher than those reported in previous studies in other industrial and residential communities. PMID:24693925

Ha, Hoehun; Olson, James R; Bian, Ling; Rogerson, Peter A

2014-05-01

386

Attrition resistant catalysts and sorbents based on heavy metal poisoned FCC catalysts  

DOEpatents

A heavy metal poisoned, spent FCC catalyst is treated by chemically impregnating the poisoned catalyst with a new catalytic metal or metal salt to provide an attrition resistant catalyst or sorbent for a different catalytic or absorption process, such as catalysts for Fischer-Tropsh Synthesis, and sorbents for removal of sulfur gases from fuel gases and flue-gases. The heavy metal contaminated FCC catalyst is directly used as a support for preparing catalysts having new catalytic properties and sorbents having new sorbent properties, without removing or passivating the heavy metals on the spent FCC catalyst as an intermediate step.

Gangwal, S.; Jothimurugesan, K.

1999-07-27

387

SUPERCRITICAL FLUID EXTRACTION OF TOXIC HEAVY METALS FROM SOLID AND AQUEOUS MATRICES  

SciTech Connect

The feasibility of using dithiocarbamate chelating agents or sulfur-containing organophosphorus reagents for the supercritical fluid extraction (SFE) of toxic heavy metals from solid and aqueous matrices is investigated. Effective extraction of heavy metal ions from both sand matrix and water samples was demonstrated by using supercritical CO2 containing dithiocarbamatechelating agents. A commercially available sulfur-containing organophosphorus reagent, Cyanex 302, was used for the extraction of toxic heavy metals from wood samples. The extraction profiles were initially rapid followed by a very low level of metal extraction, indicating that the process is limited to extraction of leachable toxic metals.

Wang, S; Lin, Yuehe; Wai, C M.

2003-04-09

388

Attrition resistant catalysts and sorbents based on heavy metal poisoned FCC catalysts  

DOEpatents

A heavy metal poisoned, spent FCC catalyst is treated by chemically impregnating the poisoned catalyst with a new catalytic metal or metal salt to provide an attrition resistant catalyst or sorbent for a different catalytic or absorption processes, such as catalysts for Fischer-Tropsh Synthesis, and sorbents for removal of sulfur gasses from fuel gases and flue-gases. The heavy metal contaminated FCC catalyst is directly used as a support for preparing catalysts having new catalytic properties and sorbents having new sorbent properties, without removing or "passivating" the heavy metals on the spent FCC catalyst as an intermediate step.

Gangwal, Santosh (Cary, NC); Jothimurugesan, Kandaswamy (Hampton, VA)

1999-01-01

389

Neutralization of an extremely acidic sludge and stabilization of heavy metals in flyash aggregates.  

PubMed

An extremely acidic, heavy metal-rich sludge (pH=-1.2) was scrubbed with a Class-F fly ash in order to simultaneously neutralize the acidity and stabilize the heavy metals contained in both wastes. This paper outlines the leaching behavior of the aggregate material generated by scrubbing. For proper fly ash/sludge ratios, the fly ash acted as an outstanding neutralizer for the acidic waste. Leaching of heavy metals from the aggregate samples was below the environmental limits within a pH range between 3 and 9. Subsequent washing of the leached aggregate with acidic CALWET solutions did not result in an additional release of heavy metals. It is proposed that coordinative bonding of the metal cations onto neutral surface sites and electrostatic adsorption led to stabilization of the heavy metals within the aggregate structure below hydrolysis pHs. PMID:16677810

Polat, M; Guler, Erkan; Lederman, Eli; Cohen, Haim

2007-01-01

390

Arbuscular mycorrhizal fungal phylogenetic groups differ in affecting host plants along heavy metal levels.  

PubMed

Arbuscular mycorrhizal fungi (AMF) are important components of soil microbial communities, and play important role in plant growth. However, the effects of AMF phylogenetic groups (Glomeraceae and non-Glomeraceae) on host plant under various heavy metal levels are not clear. Here we conducted a meta-analysis to compare symbiotic relationship between AMF phylogenetic groups (Glomeraceae and non-Glomeraceae) and host plant functional groups (herbs vs. trees, and non-legumes vs. legumes) at three heavy metal levels. In the meta-analysis, we calculate the effect size (ln(RR)) by taking the natural logarithm of the response ratio of inoculated to non-inoculated shoot biomass from each study. We found that the effect size of Glomeraceae increased, but the effect size of non-Glomeraceae decreased under high level of heavy metal compared to low level. According to the effect size, both Glomeraceae and non-Glomeraceae promoted host plant growth, but had different effects under various heavy metal levels. Glomeraceae provided more benefit to host plants than non-Glomeraceae did under heavy metal condition, while non-Glomeraceae provided more benefit to host plants than Glomeraceae did under no heavy metal. AMF phylogenetic groups also differed in promoting plant functional groups under various heavy metal levels. Interacting with Glomeraceae, herbs and legumes grew better than trees and non-legumes did under high heavy metal level, while trees and legumes grew better than herbs and non-legumes did under medium heavy metal level. Interacting with non-Glomeraceae, herbs and legumes grew better than trees and non-legumes did under no heavy metal. We suggested that the combination of legume with Glomeraceae could be a useful way in the remediation of heavy metal polluted environment. PMID:25288547

He, Lei; Yang, Haishui; Yu, Zhenxing; Tang, Jianjun; Xu, Ligen; Chen, Xin

2014-10-01

391

Role of Phosphate in the Remediation and Reuse of Heavy Metal Polluted Wastes and Sites  

Microsoft Academic Search

Heavy metal pollution is a major environmental concern because of the toxicity to humans and plants. This toxicity is lethal\\u000a even in trace quantities and metals have a great tendency to bioaccumulate. The efficiency of phosphate and apatites M10(PO4)6(OH)2, M: Metal, in particular, in removing and immobilizing heavy metals from wastewater, groundwater (as permeable reactive barriers\\u000a for in situ site

Ange Nzihou; Patrick Sharrock

2010-01-01

392

Emission characteristics of heavy metals and their behavior during coking processes.  

PubMed

Besides organic pollutants, coke production generates emissions of toxic heavy metals. However, intensive studies on heavy metal emissions from the coking industry are still very scarce. The current work focuses on assessing the emission characteristics of heavy metals and their behavior during coking. Simultaneous sampling of coal, coke, residues from air pollution control devices (APCD), effluent from coke quenching, and fly ash from different processes before and after APCD has been performed. The total heavy metal concentration in the flue gas from coke pushing (CP) was significantly higher than that from coal charging (CC) and combustion of coke oven gases (CG). Emission factors of heavy metals for CP and CC were 378.692 and 42.783 ?g/kg, respectively. During coking, the heavy metals that were contained in the feedstock coal showed different partitioning patterns. For example, Cu, Zn, As, Pb, and Cr were obviously concentrated in the inlet fly ash compared to the coke; among these metals Cu, As, and Cr were concentrated in the outlet fly ash, whereas Zn and Pb were distributed equally between the outlet fly ash and APCD residue. Ni, Co, Cd, Fe, and V were partitioned equally between the inlet fly ash and the coke. Understanding the behavior of heavy metals during coking processes is helpful for the effective control of these heavy metals and the assessment of the potential impact of their emissions on the environment. PMID:22607524

Mu, Ling; Peng, Lin; Liu, Xiaofeng; Bai, Huiling; Song, Chongfang; Wang, Ying; Li, Zhen

2012-06-01

393

Heavy metals induce oxidative stress and genome-wide modulation in transcriptome of rice root.  

PubMed

Industrial growth, ecological disturbances and agricultural practices have contaminated the soil and water with many harmful compounds, including heavy metals. These heavy metals affect growth and development of plants as well as cause severe human health hazards through food chain contamination. In past, studies have been made to identify biochemical and molecular networks associated with heavy metal toxicity and uptake in plants. Studies suggested that most of the physiological and molecular processes affected by different heavy metals are similar to those affected by other abiotic stresses. To identify common and unique responses by different metals, we have studied biochemical and genome-wide modulation in transcriptome of rice (IR-64 cultivar) root after exposure to cadmium (Cd), arsenate [As(V)], lead (Pb) and chromium [Cr(VI)] in hydroponic condition. We observed that root tissue shows variable responses for antioxidant enzyme system for different heavy metals. Genome-wide expression analysis suggests variable number of genes differentially expressed in root in response to As(V), Cd, Pb and Cr(VI) stresses. In addition to unique genes, each heavy metal modulated expression of a large number of common genes. Study also identified cis-acting regions of the promoters which can be determinants for the modulated expression of the genes in response to different heavy metals. Our study advances understanding related to various processes and networks which might be responsible for heavy metal stresses, accumulation and detoxification. PMID:24553786

Dubey, Sonali; Shri, Manju; Misra, Prashant; Lakhwani, Deepika; Bag, Sumit Kumar; Asif, Mehar H; Trivedi, Prabodh Kumar; Tripathi, Rudro Deo; Chakrabarty, Debasis

2014-06-01

394

Native Australian species are effective in extracting multiple heavy metals from biosolids.  

PubMed

Selecting native plant species with characteristics suitable for extraction of heavy metals may have multiple advantages over non-native plants. Six Australian perennial woody plant species and one willow were grown in a pot trial in heavy metal-contaminated biosolids and a potting mix. The plants were harvested after fourteen months and above-ground parts were analysed for heavy metal concentrations and total metal contents. All native species were capable of growing in biosolids and extracted heavy metals to varying degrees. No single species was able to accumulate heavy metals at particularly high levels and metal extraction depended upon the bioavailability of the metal in the substrate. Metal extraction efficiency was driven by biomass accumulation, with the species extracting the most metals also having the greatest biomass yield. The study demonstrated that Grevillea robusta, Acacia mearnsii, Eucalyptus polybractea, and E. cladocalyx have the greatest potential as phytoextractor species in the remediation of heavy metal-contaminated biosolids. Species survival and growth were the main determinants of metal extraction efficiency and these traits will be important for future screening of native species. PMID:23819263

Mok, Hoi-Fei; Majumder, Ramaprasad; Laidlaw, W Scott; Gregory, David; Baker, Alan J M; Arndt, Stefan K

2013-01-01

395

Identification of Thlaspi caerulescens genes that may be involved in heavy metal hyperaccumulation and tolerance. Characterization of a novel heavy metal transporting ATPase.  

PubMed

Thlaspi caerulescens is a heavy metal hyperaccumulator plant species that is able to accumulate extremely high levels of zinc (Zn) and cadmium (Cd) in its shoots (30,000 microg g(-1) Zn and 10,000 microg g(-1) Cd), and has been the subject of intense research as a model plant to gain a better understanding of the mechanisms of heavy metal hyperaccumulation and tolerance and as a source of genes for developing plant species better suited for the phytoremediation of metal-contaminated soils. In this study, we report on the results of a yeast (Saccharomyces cerevisae) complementation screen aimed at identifying candidate heavy metal tolerance genes in T. caerulescens. A number of Thlaspi genes that conferred Cd tolerance to yeast were identified, including possible metal-binding ligands from the metallothionein gene family, and a P-type ATPase that is a member of the P1B subfamily of purported heavy metal-translocating ATPases. A detailed characterization of the Thlaspi heavy metal ATPase, TcHMA4, demonstrated that it mediates yeast metal tolerance via active efflux of a number of different heavy metals (Cd, Zn, lead [Pb], and copper [Cu]) out of the cell. However, in T. caerulescens, based on differences in tissue-specific and metal-responsive expression of this transporter compared with its homolog in Arabidopsis (Arabidopsis thaliana), we suggest that it may not be involved in metal tolerance. Instead, we hypothesize that it may play a role in xylem loading of metals and thus could be a key player in the hyperaccumulation phenotype expressed in T. caerulescens. Additionally, evidence is presented showing that the C terminus of the TcHMA4 protein, which contains numerous possible heavy metal-binding His and Cys repeats residues, participates in heavy metal binding. When partial peptides from this C-terminal domain were expressed in yeast, they conferred an extremely high level of Cd tolerance and Cd hyperaccumulation. The possibilities for enhancing the metal tolerance and phytoremediation potential of higher plants via expression of these metal-binding peptides are also discussed. PMID:15516513

Papoyan, Ashot; Kochian, Leon V

2004-11-01

396

Inducibility of a molecular bioreporter system by heavy metals  

SciTech Connect

The authors have developed a molecular bioreporter model for detecting an invertebrate response to heavy metals in streams. The bioreporter system, pMt2-luc, utilizes a Drosophila melanogaster metallothionein promoter to regulate luciferase expression in stably transformed mosquito cells.The LucC5 clone, which was isolated from pMt2-luc transformed, hygromycin-resistant C6/36 (Aedes albopictus) cells, demonstrated a 12-fold increase in luciferase-specific activity 48 h after exposure to 13 ppm copper (Cu). In addition to Cu, exposure of LucC5 cells to 19 ppm lead (Pb) or 3 ppm mercury (Hg) for 48 h induced luciferase expression threefold and fourfold, respectively. Exposures of up to 30 ppm arsenic (As), 8 ppm cadmium (Cd), 7 ppm chromium (Cr), or 5 ppm nickel (Ni) had no effect on luciferase induction. LucC5 cells exposed to metal mixtures of 13 ppm Cu and 19 ppm Pb yielded an additive response with a 14-fold increase in luciferase expression. When organic chemicals such as phenol (3 ppm) were mixed with 13 ppm Cu, 19 ppm Pb, or 3 ppm Hg a significant reduction in luciferase activity was noted. Additionally, atomic absorption spectroscopy suggested that two of the metals, Cu and Pb, show marked differences in accumulation within the LucC5 cell line.

Klimowski, L.; Rayms-Keller, A.; Olson, K.E.; Yang, R.S.H.; Tessari, J.; Carlson, J.; Beaty, B. [Colorado State Univ., Fort Collins, CO (United States)

1996-02-01

397

Magnetic properties of alluvial soils polluted with heavy metals  

NASA Astrophysics Data System (ADS)

Magnetic properties of soils, reflecting mineralogy, concentration and grain-size distribution of Fe-oxides, proved to be useful tool in assessing the soil properties in terms of various environmental conditions. Measurement of soil magnetic properties presents a convenient method to investigate the natural environmental changes in soils as well as the anthropogenic pollution of soils with several risk elements. The effect of fluvial pollution with Cd, Cu, Pb and Zn on magnetic soil properties was studied on highly contaminated alluvial soils from the mining/smelting district (P?íbram; CZ) using a combination of magnetic and geochemical methods. The basic soil characteristics, the content of heavy metals, oxalate, and dithionite extractable iron were determined in selected soil samples. Soil profiles were sampled using HUMAX soil corer and the magnetic susceptibility was measured in situ, further detailed magnetic analyses of selected distinct layers were carried out. Two types of variations of magnetic properties in soil profiles were observed corresponding to indentified soil types (Fluvisols, and Gleyic Fluvisols). Significantly higher values of topsoil magnetic susceptibility compared to underlying soil are accompanied with high concentration of heavy metals. Sequential extraction analysis proved the binding of Pb, Zn and Cd in Fe and Mn oxides. Concentration and size-dependent parameters (anhysteretic and isothermal magnetization) were measured on bulk samples in terms of assessing the origin of magnetic components. The results enabled to distinguish clearly topsoil layers enhanced with heavy metals from subsoil samples. The dominance of particles with pseudo-single domain behavior in topsoil and paramagnetic/antiferromagnetic contribution in subsoil were observed. These measurements were verified with room temperature hysteresis measurement carried out on bulk samples and magnetic extracts. Thermomagnetic analysis of magnetic susceptibility measured on magnetic extracts indicated the presence of magnetite/maghemite in the uppermost layers, and strong mineralogical transformation of iron oxyhydroxides during heating. Magnetic techniques give valuable information about the soil Fe oxides, which are useful for investigation of the environmental effects in soil. Key words: magnetic methods, Fe oxides, pollution, alluvial soils.

Dlouha, S.; Petrovsky, E.; Boruvka, L.; Kapicka, A.; Grison, H.

2012-04-01

398

Detection of heavy metal resistance bioluminescence bacteria using microplate bioassay method.  

PubMed

Effects of different heavy metals on Vibrio harveyi, V. fischeri, Photobacterium phosphoreum and P. leiognathi were examined. Checkerboard assay was used for the detection of the natural metal tolerance levels of a large number of marine luminous eubacteria. 57 strains of luminous bacteria were investigated for their natural patterns of heavy metal tolerance. The behaviors of these strains were not homogeneous with respect to all metals tested, even within the strains belonging to the same genus. At least 1 to 4 different MICs were detected for every metal except barium and cobalt. Isolated bacteria were tested for the presence of plasmids using the modified alkaline lysis method, was effective for identification of plasmids of different sizes. This study revealed the frequency of the occurrence of plasmids in heavy metal resistance bacteria and inferred that plasmids are highly ubiquitous and predominant in most heavy metal resistant bacteria. PMID:23741856

Ranjitha, P; Karthy, E S

2012-01-01

399

Structural Study of the Incorporation of Heavy Metals into Solid Phase  

E-print Network

Structural Study of the Incorporation of Heavy Metals into Solid Phase Formed during the Oxidation of these ligands with metal cations break down to release uncomplexed metal ions that pre- cipitate, coprecipitate by the reduction of permanganate at high pH play a crucial role in the removal of TRU and metals present

Frenkel, Anatoly

400

Heavy metals modify costs of reproduction and clonal growth in the stoloniferous herb Potentilla anserina  

Microsoft Academic Search

We examined costs of sexual reproduction and clonal propagation, and their consequences for resource allocation in the clonal stoloniferous herb, Potentilla anserina, a typical pioneer species in disturbed areas. We used heavy-metal treatment in soil to create unfavourable growing conditions, because costs of reproduction are more likely to be expressed when resources are limited. We also studied whether heavy metals

Sari Koivunen; Kari Saikkonen; Timo Vuorisalo; Pia Mutikainen

2004-01-01

401

Toxicity and DNA damage in tobacco and potato plants growing on soil polluted with heavy metals  

Microsoft Academic Search

Heterezygous tobacco (Nicotiana tabacum var. xanthi) and potato (Solanum tuberosum var. Korela) plants were cultivated on soil from the site St?imice which is highly polluted with heavy metals and on nonpolluted soil from the recreational site Jeze?í, both in North Bohemia, Czech Republic. The total content, the content of bioavailable, easily mobile, and potentially mobile components of heavy metals (Cd,

Tomáš Gichner; Zde?ka Patková; Ji?ina Száková; Kate?ina Demnerová

2006-01-01

402

Biosorption of heavy metal ions from aqueous solution by red macroalgae  

Microsoft Academic Search

Biosorption is an effective process for the removal and recovery of heavy metal ions from aqueous solutions. The biomass of marine algae has been reported to have high biosorption capacities for a number of heavy metal ions. In this study, four species of red seaweeds Corallina mediterranea, Galaxaura oblongata, Jania rubens and Pterocladia capillacea were examined to remove Co(II), Cd(II),

Wael M. Ibrahim

2011-01-01

403

Toenail as a biomarker of heavy metal exposure via drinking water: a systematic review.  

PubMed

Abstract Toenail is metabolic end product of the skin, which can provide information about heavy metal accumulation in human cells. Slow growth rates of toenail can represent heavy metal exposure from 2 to 12 months before the clipping. The toenail is a non-invasive biomarker that is easy to collect and store and is stable over time. In this systematic review, the suitability of toenail as a long-term biomarker was reviewed, along with the analysis and validation of toenail and confounders to heavy metal. This systematic review has included 30 articles chosen from a total of 132 articles searched from online electronic databases like Pubmed, Proquest, Science Direct, and SCOPUS. Keywords used in the search included "toenail", "biomarker", "heavy metal", and "drinking water". Heavy metal in toenail can be accurately analyzed using an ICP-MS instrument. The validation of toenail heavy metal concentration data is very crucial; however, the Certified Reference Material (CRM) for toenail is still unavailable. Usually, CRM for hair is used in toenail studies. Confounders that have major effects on heavy metal accumulation in toenail are dietary intake of food and supplement, smoking habit, and overall health condition. This review has identified the advantages and limitations of using toenail as a biomarker for long-term exposure, which can help future researchers design a study on heavy metal exposure using toenail. PMID:25332289

Ab Razak, Nurul Hafiza; Praveena, Sarva Mangala; Hashim, Zailina

2014-10-21

404

The distribution of the heavy metal accumulation rate in the biomass of three Daphnia species  

SciTech Connect

The difference in the accumulation rate of a mixture of heavy metals in aquatic organisms is of considerable interest because of its importance in the prediction of the effect of pollutants in aquatic systems. In this study the authors are making an effort to evaluate the accumulation patterns of pollutants in aquatic organisms by establishing a relation between the level of an accumulated mixture of heavy metals (Cd, Zn, Pb, As, Hg) in individuals of Daphnia magna, Daphnia pulicaria and Daphnia galeata and its dry weight with respect to the form of heavy metals in the aquatic environment. One age group of Daphnia species (10 day old) were exposed to 5 ppb, 10 ppb and 20 ppb of the mixture of heavy metals for 24 hours in three different experiments. In the first experiment the mixture of heavy metals was present exclusively in labelled algae (Scendesmus actus), in the second in an aquatic medium with non labelled algae, and in the third experiment the mixture of heavy metals was dissolved in the aquatic medium only without the addition of algae. The concentration of the heavy metal mixture in individuals of D.magna; D.pulicaria and D.galeata was determined using atomic absorption spectrometry. Results were statistically evaluated and the rate of accumulation and influence of various heavy metals in the biomass of three Daphnia species is discussed.

Gajula, V.K.; Hovorka, J.; Stuchlik, E. [Charles Univ., Prague (Czech Republic)

1995-12-31

405

Heavy metals in coastal wetland sediments of the Pearl River Estuary, China  

Microsoft Academic Search

Sediment quality in coastal wetlands of the Pearl River Estuary was concerned since the wetlands were used for land reclamation, aquaculture and wildlife protection, and meanwhile served as one of the main ultimate sinks for large amount of heavy metals discharged from the rapidly developing Pearl River Delta. Total concentrations of heavy metal, such as Zn, Ni, Cr, Cu, Pb,

QuSheng Li; ZhiFeng Wu; Bei Chu; Na Zhang; ShaSha Cai; JianHong Fang

2007-01-01

406

Heavy metals balance in Polish and Dutch agronomy: Actual state and previsions for the future  

Microsoft Academic Search

This paper presents the state of agro-ecosystem contamination with heavy metals in relation to the level of agricultural development. For this, the Polish and Dutch agricultural situations were compared. The intensive animal and vegetable production observed in the Netherlands over the past 20–30 years was found to substantially contribute to the heavy metal input of these systems. Agriculture in Poland

Jacek Dach; Dick Starmans

2005-01-01

407

Plant responses to abiotic stresses: heavy metal-induced oxidative stress and protection by mycorrhization  

Microsoft Academic Search

The aim of this review is to assess the mode of action and role of antioxidants as protection from heavy metal stress in roots, mycorrhizal fungi and mycor- rhizae. Based on their chemical and physical proper- ties three different molecular mechanisms of heavy metal toxicity can be distinguished: (a) production of reactive oxygen species by autoxidation and Fenton reaction; this

Andres Schutzendubel; Andrea Polle

2002-01-01

408

Development of protein based bioremediation and drugs for heavy metal toxicity  

SciTech Connect

Structural studies were performed on several proteins of the bacterial detoxification system. These proteins are responsible for binding (MerP) and transport of heavy metals, including mercury, across membranes. The structural information obtained from NMR experiments provides insight into the selectivity and sequestration processes towards heavy metal toxins.

Opella, Stanley J.

2001-09-18

409

In situ detection of heavy metal substituted chlorophylls in water plants  

Microsoft Academic Search

The in vivo substitution of magnesium, the central atom of chlorophyll, by heavy metals (mercury, copper, cadmium, nickel, zinc, lead) leads to a breakdown in photosynthesis and is an important damage mechanism in heavy metal-stressed plants. In this study, a number of methods are presented for the efficient in situ detection of this substitution (i.e. in whole plants or in

Hendrik Küpper; Frithjof Küpper; Martin Spiller

1998-01-01

410

The use of vetiver grass ( Vetiveria zizanioides) in the phytoremediation of soils contaminated with heavy metals  

Microsoft Academic Search

Recent research has shown that phytoextraction approaches often require soil amendments, such as the application of EDTA, to increase the bioavailability of heavy metals in soils. However, EDTA and EDTA–heavy metal complexes can be toxic to plants and soil microorganisms and may leach into groundwater, causing further environmental pollution. In the present study, vetiver grass (Vetiveria zizanioides) was studied for

Yahua Chen; Zhenguo Shen; Xiangdong Li

2004-01-01

411

A Pyoverdin Siderophore Produced By Pseudomonas aeruginosa CHL-004 Binds Lead And Other Heavy Metals  

EPA Science Inventory

Heavy metal pollution in soils, sediments and wastewater poses a significant environmental and public health threat due to toxicity and the potential for bioaccumulation in both plant and animal tissues. Remediation of heavy metals in soils and sediments using solely physical or...

412

A Pyoverdin Siderophore Produced By Pseudomonas aeruginosa CHL-004 Binds Lead And Other Heavy Metals - (Poster)  

EPA Science Inventory

Heavy metal pollution in soils, sediments and wastewater poses a significant environmental and public health threat due to toxicity and the potential for bioaccumulation in both plant and animal tissues. Remediation of heavy metals in soils and sediments using solely physical or...

413

Assessment of heavy metal pollution in surface soils of urban parks in Beijing, China  

Microsoft Academic Search

Assessing the concentration of potentially harmful heavy metals in the soil of urban parks is imperative in order to evaluate the potential risks to residents and tourists. To date, little research on soil pollution in China’s urban parks has been conducted. To identify the concentrations and sources of heavy metals, and to assess the soil environmental quality, samples were collected

Tong-Bin Chen; Yuan-Ming Zheng; Mei Lei; Ze-Chun Huang; Hong-Tao Wu; Huang Chen; Ke-Ke Fan; Ke Yu; Xiao Wu; Qin-Zheng Tian

2005-01-01

414

Heavy Metal Pollution in Air-Water-Soil-Plant System of Zhuzhou City, Hunan Province, China  

Microsoft Academic Search

The sources, distribution and mobility of heavy metals in Zhuzhou City, Hunan Province, China were systematically studied based on environmental monitoring data and random sampling from fields and markets. The significant positive correlations between some pairs of heavy metals (total Cd–Hg, total Cu–Pb) within the Zhuzhou section of the Xiang River may indicate that they are coming from the same

Wang Haiyan; Arne O. Stuanes

2003-01-01

415

An Evaluation of Bivalves as Biomonitors of Heavy Metals Pollution in Marine Waters  

Microsoft Academic Search

Heavy metals (namely Cr, Cu, Zn, As, Hg, Pb, Ni, and Ag) that are present at concentrations common in ambient marine waters can cause adverse effects in shellfish. Such effects can significantly impact the trophic structure of a biological community. Heavy metals uptake is dependent on both geochemical and biological factors. In bivalves, the extent of accumulation is a function

Dean W. Boening

1999-01-01

416

Multivariate analysis of soil heavy metal pollution and landscape pattern in Changhua county in Taiwan  

Microsoft Academic Search

This study applied factor analysis and landscape indices of 55 sampling sites in Changhua county in Taiwan to characterize the factor patterns of eight soil heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) and the interrelation patterns of these soil heavy metals, landscape and human activities. The landscape analysis results indicated that landscape indices can elucidate spatial

Yu-Pin Lin; Tung-Po Teng; Tsun-Kuo Chang

2002-01-01

417

Heavy metals in sediments of two Chesapeake Bay tributaries — Wicomico and Pocomoke Rivers  

Microsoft Academic Search

Aquatic sediments can be both sinks and sources of heavy metals. The objective of this study was to measure the concentrations of heavy metals in sediments and sediment-porewaters of two Chesapeake Bay tributaries — Wicomico (WR) and Pocomoke (PR) Rivers so as to better understand the contributions of point (sewage treatment plant — STP) or non-point (agricultural runoff) sources of

Gian Gupta; Makesh Karuppiah

1996-01-01

418

Exploiting the genetic and biochemical capacities of bacteria for the remediation of heavy metal pollution  

Microsoft Academic Search

The threat of heavy metal pollution to public health and wildlife has led to an increased interest in developing systems that can remove or neutralise its toxic effects in soil, sediments and wastewater. Unlike organic contaminants, which can be degraded to harmless chemical species, heavy metals cannot be destroyed. Remediating the pollution they cause can therefore only be envisioned as

Marc Valls; V??ctor de Lorenzo

2002-01-01

419

HEAVY METAL POLLUTION OF SOIL AND A NEW APPROACH TO ITS REMEDIATION: RESEARCH EXPERIENCES IN JAPAN  

Microsoft Academic Search

Rapid industrialization in the 1960s caused heavy metals such as cadmium (Cd) to severely pollute soil in Japan. The Agricultural Land Soil Pollution Prevention Law was enacted in 1970 to cope with the heavy metal pollution. Cd, in particular, has been recognized as one of the most detrimental elements in Japan because of the so-called \\

Tomoyuki Makino

420

Research on Absorption of Heavy Metal in River Sediment by Lolium Perenne  

Microsoft Academic Search

In order to alleviate pollution of urban sewage river sediment, planting experiment is conducted to study phytoremediation of Lolium Perenne to heavy metal pollution in the circumstance of adding hydrogen peroxide before planting. Results show that after adding hydrogen peroxide before planting Lolium Perenne in sediment the accumulation number of heavy metal in root is more than the one in

Li Hong-xia

2011-01-01

421

Progress in the remediation of hazardous heavy metal-polluted soils by natural zeolite  

Microsoft Academic Search

Hazardous heavy metal pollution of soils is an increasingly urgent problem all over the world. The zeolite as a natural amendment has been studied extensively for the remediation of hazardous heavy metal-polluted soils with recycling. But its theory and application dose are not fully clear. This paper reviews the related aspects of theory and application progress for the remediation of

Wei-yu Shi; Hong-bo Shao; Hua Li; Ming-an Shao; Sheng Du

2009-01-01

422

Microorganism-Plant Combined Bioremediation on Heavy Metal Contaminated Soil In the Industrial District  

Microsoft Academic Search

Heavy metal contaminated soil problem has already become the global focus. With the increasing attention to the environment protection, scientist began to search new methods for remediation of contaminated soil. This paper mainly studied the effect of microorganism-plant combined bioremediation on contaminated soil in the industrial district, hoping to provide an effective bioremediation technique for heavy metal contaminated soil. In

Zhou Guoying; Li Lin; Li He; He Yuanhao

2009-01-01

423

Use of Sequential Extraction in the Study of Heavy Metal Retention by Silty Soils  

Microsoft Academic Search

This study focused on the capability of two silty soils (tills) having low clay contents and CEC to retain and release two heavy metals, Pb and Cu. Samples of two non contaminated till deposits from the Eastern Townships region of Quebec, Canada, were artificially contaminated with concentrated solutions of these heavy metals. The latter were later extracted from the various

Alexandre R. Cabral; Guy Lefebvre

1998-01-01

424

Experimental Assessment of Using Soluble Humic Substances for Remediation of Heavy Metal Polluted Soils  

Microsoft Academic Search

Since heavy metals are nondegradable and strongly bonded in soils, remediation of heavy metal polluted soils by extraction is difficult and current extraction techniques require harsh chemicals such as ethylenediaminetetraacetic acid (EDTA). However, use of EDTA is environmentally problematic because of costs, persistence, toxicity and deterioration of soil structure. Therefore, the potential of soluble natural humic substances (HS) to extract

O. K. Borggaard; H. C. B. Hansen; P. E. Holm; J. K. Jensen; S. B. Rasmussen; N. Sabiene; L. Steponkaite; B. W. Strobel

2009-01-01

425

Removal of Heavy Metals from Calcareous Contaminated Soils by EDTA Leaching  

Microsoft Academic Search

The performance of EDTA for the treatment of calcareous soils contaminated with heavy metals from mining and smelting activities was evaluated in this study. Soil samples containing variable levels of contamination, from 500 to 35 000 mg kg-1 Pb and 700 to 20 000 mg kg-1 Zn, were subjected to EDTA treatment and the extraction of heavy metals was found

N. Papassiopi; S. Tambouris; A. Kontopoulos

1999-01-01

426

Effect of Drying on Heavy Metal Fraction Distribution in Rice Paddy Soil  

PubMed Central

An understanding of how redox conditions affect soil heavy metal fractions in rice paddies is important due to its implications for heavy metal mobility and plant uptake. Rice paddy soil samples routinely undergo oxidation prior to heavy metal analysis. Fraction distribution of Cu, Pb, Ni, and Cd from paddy soil with a wide pH range was investigated. Samples were both dried according to standard protocols and also preserved under anaerobic conditions through the sampling and analysis process and heavy metals were then sequentially extracted for the exchangeable and carbonate bound fraction (acid soluble fraction), iron and manganese oxide bound fraction (reducible fraction), organic bound fraction (oxidizable fraction), and residual fraction. Fractions were affected by redox conditions across all pH ranges. Drying decreased reducible fraction of all heavy metals. Curesidual fraction, Pboxidizable fraction, Cdresidual fraction, and Niresidual fraction increased by 25%, 33%, 35%, and >60%, respectively. Pbresidual fraction, Niacid soluble fraction, and Cdoxidizable fraction decreased 33%, 25%, and 15%, respectively. Drying paddy soil prior to heavy metal analysis overestimated Pb and underestimated Cu, Ni, and Cd. In future studies, samples should be stored after injecting N2 gas to maintain the redox potential of soil prior to heavy metal analysis, and investigate the correlation between heavy metal fraction distribution under field conditions and air-dried samples. PMID:24823670

Qi, Yanbing; Huang, Biao; Darilek, Jeremy Landon

2014-01-01

427

[Mechanism of metallothionein gene activation mediated by heavy-metal dependent transcription factor MTF-1].  

PubMed

Transcriptional activation of metallothionein (MT) genes by heavy metals is a valuable system for understanding the functions of MT as well as the cellular response against heavy metals. Although it is now known that heavy metal signals culminating in MT induction converge upon a transcription factor MTF-1, the mechanism underlying the MTF-1 response to heavy metals has not been elucidated. To address this issue, we investigated various aspects of the in vivo response of MTF-1 against heavy metals. Chromatin immunoprecipitation assay showed that heavy metal-dependent DNA binding of MTF-1 is the critical step in vivo. MTF-1 is primarily localized in the nucleus so that heavy metal-dependent nuclear translocation demonstrated by other groups does not seem to be universal and hence may not be critical for activation of MTF-1. In the six Zn finger motifs, the hallmark of MTF-1, the third and the fourth fingers are essential for the nuclear localization of MTF-1. Furthermore, all fingers except the last are important for transcriptional activation function of MTF-1, suggesting their key role for MTF-1 function. Also, a cysteine cluster structure located in the C-terminal region of MTF-1 is critical for transactivating function of MTF-1. These results suggest a central role of the Zn-finger domain and intramolecular cooperation through a structural change of MTF-1 for its response to heavy metal challenge. PMID:17409697

Otsuka, Fuminori; Ohno, Shotaro; Suzuki, Kaoru; Takahashi, Kazuko; Ohsawa, Motoyasu; Koizumi, Shinji

2007-04-01

428

HEAVY METALS IN SELECTED EDIBLE VEGETABLES AND ESTIMATION OF THEIR DAILY INTAKE IN SANANDAJ, IRAN  

Microsoft Academic Search

The levels of four different heavy metals (cadmium (Cd), lead (Pb), chromium (Cr) and copper (Cu)) were determined in various vegetables (leek (Allium ampeloprasum), sweet basil (Ocimum basilicum), parsley (Petroselinum crispum), garden cress (Lepidium sativum) and tar- ragon (Artemisia dracunculus)) cultivated around Sanandaj City. The contributions of the veg- etables to the daily intake of heavy metals from vegetables were

Afshin Maleki; Masoud Alasvand Zarasvand

429

Study of the Chemical Interaction between Barks and Heavy Metal Cations in the Sorption Process  

Microsoft Academic Search

The chemical mechanism displayed in the sorption of heavy metal cations on barks was discussed through a modelling study of adsorption in relation to the nature of the ligand borne by the chemical components of the bark sorbent. The adsorption isotherms of five heavy metal cations (Cr, Cu, Ni, Pb, Zn) on five species of barks (Sweet chestnut, Oak, Douglas

FABIENNE MARTIN-DUPONT; VINCENT GLOAGUEN; MICHEL GUILLOTON; ROBERT GRANET; PIERRE KRAUSZ

2006-01-01

430

Effects of Listening to Heavy Metal Music on College Women: A Pilot Study  

ERIC Educational Resources Information Center

College students are typically very identified with popular music and spend many hours listening to their music of preference. To investigate the effects of heavy metal music, we compared the responses of 18 female undergraduate college students to a baseline silence condition (A) and a heavy metal music condition (B). Dependent measures included:…

Becknell, Milton E.; Firmin, Michael W.; Hwang, Chi-en; Fleetwood, David M.; Tate, Kristie L.; Schwab, Gregory D.

2008-01-01

431

ANALYSIS OF THE ELECTRON EXCITATION SPECTRA IN HEAVY RARE EARTH METALS, HYDRIDES AND OXIDES  

E-print Network

397 ANALYSIS OF THE ELECTRON EXCITATION SPECTRA IN HEAVY RARE EARTH METALS, HYDRIDES AND OXIDES C thin evaporated foils of heavy rare earths (Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) in three different chemical states (metal, hydride and oxide) exhibit two main peaks due to collective « plasmon » excitations

Boyer, Edmond

432

Toxicity of heavy metals to microorganisms and microbial processes in agricultural soils: a review  

Microsoft Academic Search

An increasing body of evidence suggests that microorganisms are far more sensitive to heavy metal stress than soil animals or plants growing on the same soils. Not surprisingly, most studies of heavy metal toxicity to soil microorganisms have concentrated on effects where loss of microbial function can be observed and yet such studies may mask underlying effects on biodiversity within

Ken E Giller; Ernst Witter; Steve P Mcgrath

1998-01-01

433

Retention of heavy metals by carboxyl functional groups of biochars in small arms range soil  

Technology Transfer Automated Retrieval System (TEKTRAN)

Long-term effectiveness of biochar for heavy metal stabilization depends upon biochar’s sorptive property and recalcitrance in soil. To understand the role of carboxyl functional groups on heavy metal stabilization, cottonseed hull biochar and flax shive steam activated biochar having low O/C ratio...

434

Environmental Pollution Studies in an Underdeveloped Country: (1) Heavy Metal Pollution in Ibadan, Nigeria.  

ERIC Educational Resources Information Center

Reviews research studies related to the monitoring of trace heavy metals in environmental samples such as plants, water, soils, and other natural resources in the city of Ibadan, Nigeria. Research results indicate a significant increase in toxic heavy metal levels has occurred, implying the need for environmental education. (Contains 31…

Onianwa, P. C.

1993-01-01

435

Studies on the accumulation of heavy metal elements in biological systems  

Microsoft Academic Search

Summary The selective accumulation of heavy metal ions byChlorella regularis was investigated. The amounts of heavy metal ions taken up byChlorella cells decreases in the following order:\\u000a$$\\\\begin{gathered} UO_2^{2 + } \\\\gg Cu^{2 + } \\\\gg Zn^{2 + } \\\\gtrsim Ba^{2 + } \\\\bar \\\\sim Mn^{2 + } \\\\gtrsim Co^{2 + } \\\\bar \\\\sim Cd^{2 + } \\\\hfill \\\\\\\\ \\\\gtrsim

Akira Nakajima; Takao Horikoshi; Takashi Sakaguchi

1981-01-01

436

A review of potentially low-cost sorbents for heavy metals  

Microsoft Academic Search

The use of low-cost sorbents has been investigated as a replacement for current costly methods of removing heavy metals from solution. Natural materials or waste products from certain industries with a high capacity for heavy metals can be obtained, employed, and disposed of with little cost. Modification of the sorbents can also improve adsorption capacity. In this review, an extensive

Susan E. Bailey; Trudy J. Olin; R. Mark Bricka; D. Dean Adrian

1999-01-01

437

Determination of mobile heavy metal fraction in soil: Results of a pot experiment with sewage sludge  

Microsoft Academic Search

The development of a method using a chelating resin to assess heavy metal mobility in soil and the first results obtained from a pot experiment with sewage sludge additions were studied. The resin was Chelex 100 with the calcium (Ca)?form of the resin proving to be best suited for the extraction. The efficiency of recovery of the heavy metals from

Enzo Lombi; Martin H. Gerzabek

1998-01-01

438

Bioaccumulation of heavy metals in pre-fledgling tree swallows, Tachycineta bicolor  

Microsoft Academic Search

Wetlands in urbanized areas are frequently degraded by human activity. The Hackensack River Estuary in Northeastern New Jersey is no exception. This estuary contains over 1,600 acres of landfill, and receives various levels of treated effluent from seven different sewage treatment plants. Heavy metals are a common pollutant in the Hackensack River Basin. Bioaccumulation of heavy metals in birds is

Mark L. Kraus

1989-01-01

439

40 CFR Appendix A to Part 191 - Table for Subpart B  

Code of Federal Regulations, 2010 CFR

...containing 1,000 metric tons of heavy metal (MTHM) exposed to a burnup between...megawatt-days per metric ton of heavy metal (MWd/MTHM) and 40,000 MWd...determine the original metric tons of heavy metal in the reactor fuel that...

2010-07-01

440

40 CFR Appendix A to Part 191 - Table for Subpart B  

Code of Federal Regulations, 2013 CFR

...containing 1,000 metric tons of heavy metal (MTHM) exposed to a burnup between...megawatt-days per metric ton of heavy metal (MWd/MTHM) and 40,000 MWd...determine the original metric tons of heavy metal in the reactor fuel that...

2013-07-01

441

40 CFR Appendix A to Part 191 - Table for Subpart B  

Code of Federal Regulations, 2012 CFR

...containing 1,000 metric tons of heavy metal (MTHM) exposed to a burnup between...megawatt-days per metric ton of heavy metal (MWd/MTHM) and 40,000 MWd...determine the original metric tons of heavy metal in the reactor fuel that...

2012-07-01

442

40 CFR Appendix A to Part 191 - Table for Subpart B  

Code of Federal Regulations, 2014 CFR

...containing 1,000 metric tons of heavy metal (MTHM) exposed to a burnup between...megawatt-days per metric ton of heavy metal (MWd/MTHM) and 40,000 MWd...determine the original metric tons of heavy metal in the reactor fuel that...

2014-07-01

443

40 CFR Appendix A to Part 191 - Table for Subpart B  

Code of Federal Regulations, 2011 CFR

...containing 1,000 metric tons of heavy metal (MTHM) exposed to a burnup between...megawatt-days per metric ton of heavy metal (MWd/MTHM) and 40,000 MWd...determine the original metric tons of heavy metal in the reactor fuel that...

2011-07-01

444

[Bioaccumulation of heavy metals in macrofungi and its application in ecological remediation].  

PubMed

As an important type of environmental biological resources, macrofungi are vitally useful in our life. Compared with green plants, macrofungi can accumulate high concentrations of heavy metals such as Cd, Pb and Hg. In this paper, the bioaccumulation of heavy metals in macrofungi and the advantages of using macrofungi in ecological remediation of heavy metals pollution were discussed. The main factors affecting the bioaccumulation of heavy metals in macrofungi, include the species, ecological types, bioaccumulation characteristics and genetic potentials of macrofungi, the morphologic traits, parts and lifetime of mycelium and fruiting bodies, the intervals between fructifications, and the ecological environments. It was suggested that to screen out the macrofungi with effective bioaccumulation of heavy metals, be prone to artificially cultured, better adjustable to environments and easily post-disposed would be the important domain to be explored in the future. PMID:17974263

An, Xin-Long; Zhou, Qi-Xing

2007-08-01

445

[Heavy metal pollution ecology of macro-fungi: research advances and expectation].  

PubMed

Macro-fungi are the main component of biosphere and one of the ecological resources, and play very important roles in matter cycling and in maintaining ecological balances. This paper summarized and reviewed the research advances in the eco-toxicological effects of heavy metals on macro-fungi, the bioaccumulation function of macro-fungi on heavy metals, the ecological adaptation mechanisms of macro-fungi to heavy metal pollution, the role of macro-fungi as a bio-indicator of heavy metal pollution, and the potential of macro-fungi in the ecological remediation of contaminated environment. To strengthen the researches on the heavy metal pollution ecology of macro-fungi would be of practical significance in the reasonable utilization of macro-fungi resources and in the ecological remediation of contaminated environment. PMID:18975768

Zhou, Qi-xing; An, Xin-long; Wei, Shu-he

2008-08-01

446

Ecological risk assessment and sources of heavy metals in sediment from Daling River basin.  

PubMed

To investigate the distribution, source, and ecological risk of heavy metals in Daling River basin, 28 surface sediments collected in this region were analyzed by experimental and theoretical methods. Seven heavy metals, including Pb, Cr, Hg, Cu, As, Cd, and Zn, were detected in all samples. Monte Carlo simulation was used to assess the ecological risks of these heavy metals. It was found that the pollution of Cd was the most serious; the ecological risks in Daling River and Bohai Bay were significantly higher than those in estuary, Bohai Sea, and wetland, but overall, the ecological risks of these heavy metals were low to aquatic organisms in Daling River basin at present. Correlation analysis, principal component analysis, and cluster analysis showed that these heavy metals might originate from the same pollution sources located near Daling River and Bohai Bay. PMID:25378031

Zhao, Lei; Mi, Dong; Chen, Yifu; Wang, Luo; Sun, Yeqing

2014-11-01

447

Bioleaching of heavy metal from woody biochar using Acidithiobacillus ferrooxidans and activation for adsorption.  

PubMed

A woody biochar which was the byproduct of gasification of sawdust was treated with bioleaching by Acidithiobacillus ferrooxidans. After bioleaching, most heavy metal was removed from biochar. Leaching efficiency of heavy metal was efficient in a wide pulp density range from 1% to 10% (w/v) and decreased only a little with the increase in pulp density. It made application of biochar free of heavy metal risk. Benefitting from the improvement in functional group composition and pore structure after bioleaching, adsorption capacity of biochar to methylene blue and heavy metal was enhanced greatly. Adsorption of methylene blue could be described by pseudo-second-order model and Langmuir equation and the enhancement was mainly caused by the modification of physical character of biochar. Adsorption of heavy metal could be described by Freundlich equation and was mainly determined by chemical character of biochar. PMID:23978608

Wang, Buyun; Li, Cuiping; Liang, Hui

2013-10-01

448

An artificial tongue fluorescent sensor array for identification and quantitation of various heavy metal ions.  

PubMed

Herein, a small-molecule fluorescent sensor array for rapid identification of seven heavy metal ions was designed and synthesized, with its sensing mechanism mimicking that of a tongue. The photoinduced electron transfer and intramolecular charge transfer mechanism result in combinatorial interactions between sensor array and heavy metal ions, which lead to diversified fluorescence wavelength shifts and emission intensity changes. Upon principle component analysis (PCA), this result renders clear identification of each heavy metal ion on a 3D spatial dispersion graph. Further exploration provides a concentration-dependent pattern, allowing both qualitative and quantitative measurements of heavy metal ions. On the basis of this information, a "safe-zone" concept was proposed, which provides rapid exclusion of versatile hazardous species from clean water samples based on toxicity characteristic leaching procedure standards. This type of small-molecule fluorescent sensor array could open a new avenue for multiple heavy metal ion detection and simplified water quality analysis. PMID:25144824

Xu, Wang; Ren, Changliang; Teoh, Chai Lean; Peng, Juanjuan; Gadre, Shubhankar Haribhau; Rhee, Hyun-Woo; Lee, Chi-Lik Ken; Chang, Young-Tae

2014-09-01

449

Use of regulatory documents for assessing the contamination of soils with heavy metals  

NASA Astrophysics Data System (ADS)

The chronological review and analysis of the existing regulatory documents relevant to the assessment of soil contamination with heavy metals have been presented. Attention has been given to the incorrect use of the term "total heavy metal content" and the method of its determination in a 5 M nitric acid solution recommended by some regulatory documents. The maximum permissible concentrations (MPCs) and tentatively permissible concentrations (TPCTPCs) for the total heavy metal contents are based on the above method; therefore, the conventional methods of determining the true total contents of heavy metals overestimate the degree of contamination. To avoid confusion, it has been proposed to call the content of a heavy metal in a 5 M nitric acid solution the "pseudototal" content and to compare the experimental results with the MPC or TPCTPC values only if the methods recommended by the regulatory documents were used.

Nesterova, O. V.; Tregubova, V. G.; Semal, V. A.

2014-11-01

450

Accumulation of heavy metals in water, sediments and wetland plants of kizilirmak delta (samsun, Turkey).  

PubMed

In this study, concentrations of heavy metals (Fe, Mn, Ni, Co, Zn, Cu, and Pb) were measured in water bodies including streams, bottom sediments and various wetland plants of K?z?l?rmak Delta. K?z?l?rmak Delta is one of the largest and the most important natural wetlands in Turkey and has been protected by Ramsar convention since 1993. The heavy metal concentrations in water were found lower than that of national standards for protected lakes and reserves. In bottom sediments and wetland plants, however, the accumulated amounts of different heavy metals varied in the following order: Fe>Mn>Zn>Ni>Co>Cu>Pb, and Fe>Mn>Zn>Ni>Co respectively. Heavy metal uptake of Hydrocharis morsus-ranae and Myriophyllum verticillatum plants among others were found far above the toxic levels and they might be used as bio-indicators and heavy metal accumulators in polluted natural areas. PMID:25174426

Engin, M S; Uyanik, A; Kutbay, H G

2015-01-01

451

Analysis of Accumulating Ability of Heavy Metals in Lotus (Nelumbo nucifera) Improved by Ion Implantation  

NASA Astrophysics Data System (ADS)

Heavy metals have seriously contaminated soil and water, and done harm to public health. Academician WANG Naiyan proposed that ion-implantation technique should be exploited for environmental bioremediation by mutating and breeding plants or microbes. By implanting N+ into Taikonglian No.1, we have selected and bred two lotus cultivars, Jingguang No.1 and Jingguang No.2. The present study aims at analyzing the feasibility that irradiation can be used for remediation of soil and water from heavy metals. Compared with parent Taikonglian No.1, the uptaking and accumulating ability of heavy metals in two mutated cultivars was obviously improved. So ion implantation technique can indeed be used in bioremediation of heavy metals in soil and water, but it is hard to select and breed a cultivar which can remedy the soil and water from all the heavy metals.

Zhang, Jianhua; Wang, Naiyan; Zhang, Fengshou

2012-05-01

452

Heavy metal levels in goats from Notasulga, Alabama  

SciTech Connect

Goat meat farming is increasing in popularity in southeastern region of United States. In order to monitor environmental contamination of heavy metals in goat meat, samples of liver, kidney, and muscle were collected from 20 goats on a goat farm in Notasulga, Alabama. These samples were analyzed by Inductively Coupled Plasma Atomic Emission Spectroscopy. The copper concentration was significantly higher in livers than the concentration in kidneys and muscles. Lead, cadmium, and zinc levels did not show any significant differences between liver, kidney, and muscle samples. The concentrations of lead and copper in livers and cadmium in kidneys were significantly different in males when compared to females. However, in muscle, the concentrations of lead, cadmium, copper, and zinc showed no significant difference between male and female or between young and old goats. Further, the concentrations of lead in livers and cadmium in kidneys showed a significant difference between young and old goats.

Khan, A.T.; Diffay, B.C.; Forester, D.M.; Thompson, S.J. [Tuskegee Univ., AL (United States). School of Veterinary Medicine; Mielke, H.W. [Xavier Univ. of Louisiana, New Orleans, LA (United States)

1994-12-31

453

Portable X-Ray, K-Edge Heavy Metal Detector  

SciTech Connect

The X-Ray, K-Edge Heavy Metal Detection System was designed and built by Ames Laboratory and the Center for Nondestructive Evaluation at Iowa State University. The system uses a C-frame inspection head with an X-ray tube mounted on one side of the frame and an imaging unit and a high purity germanium detector on the other side. the inspection head is portable and can be easily positioned around ventilation ducts and pipes up to 36 inches in diameter. Wide angle and narrow beam X-ray shots are used to identify the type of holdup material and the amount of the contaminant. Precise assay data can be obtained within minutes of the interrogation. A profile of the containerized holdup material and a permanent record of the measurement are immediately available.

Fricke, V.

1999-10-25

454

Investigation of heavy metal effects on immobilized paraoxanase by glutaraldehyde.  

PubMed

Serum paraoxonase 1 (PON1) was purified from bovine serum using hydrophobic interaction chromotography on Sepharose 4B-coupled l-tyrosine 1-naphthylamine gel, and monitored by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Paraoxonase enzyme was immobilized using different ratios of glutaraldehyde and the maximum activity was observed with 7% glutaraldehyde. The effects of inhibition by Mn(+2), Co(+2) and Cu(+2) heavy metals on the immobilized and free enzyme activities were studied. At the optimum pH and temperature, the K(m) and V(max) kinetic values for bovine serum paraoxonase and immobilized paraoxonase towards paraoxon substrate were determined as 0.296?×?10(-3) M & 37.04 EU vs. 0.727-10(-3) M & 36.36 EU, respectively. PMID:22233542

Bilen, Çi?dem; Beyazta?, Serap; Arslan, Oktay; Güler, Özen Özensoy

2013-06-01

455

Selenium and heavy metals in San Francisco Bay diving ducks  

USGS Publications Warehouse

We analyzed for selenium (Se) and heavy metals in greater scaups (Aythya marila) and surf scoters (Melanitta perspicillata) collected from southern San Francisco Bay in March and April 1982. There were no differences (P > 0.05) between species for liver concentrations of silver (Ag), mercury (Hg), or lead (Pb). Copper (Cu) (P 0.05) between the 2 species. The geometric mean cadmium (Cd) concentration in scoter kidneys (24.6 ppm, dry wt) was higher than in scaups (15.5 ppm) (0.1 > P > 0.05). Liver concentrations of Hg and Se were correlated (P < 0.01). The toxicological significance of some elements in these species is not known. However, Se levels in scoters (34.4 ppm, dry wt) were similar to those in livers of dabbling ducks (Anas spp.) in the nearby San Joaquin Valley where reproduction was impaired severely.

Ohlendorf, H.M.; Lowe, R.W.; Kelly, P.R.; Harvey, T.E.

1986-01-01

456

Heavy-metal concentrations in three owl species from Korea.  

PubMed

This study presents concentrations of heavy metals (iron, zinc, manganese, copper, lead, and cadmium) in livers of three owl species from Korea. Essential trace elements (iron, zinc, manganese, and copper) did not differ among the owl species. We suggest that the essential elements are within the normal range and are maintained by normal homeostatic mechanisms. Lead and cadmium concentrations in Eurasian Eagle Owls (Bubo bubo) were significantly lower than in Brown Hawk Owls (Nixos scutulata) and Collared Scops Owls (Otus lempiji). Lead and cadmium concentrations in Korean owl species were at background levels; lead concentrations in two Collared Scops Owls were above background concentrations. Lead and cadmium concentrations were similar to concentrations previously reported in owls from other parts of the world. We suggest that lead and cadmium concentrations in Korean owls are below toxic concentrations. PMID:17955366

Kim, Jungsoo; Lee, Hang; Koo, Tae-Hoe

2008-01-01

457

Dynamic strain aging in a tungsten heavy metal  

SciTech Connect

Tungsten heavy metal is a mostly two-phase tungsten-base alloy containing spherical tungsten grains embedded in a f.c.c. binder. Good ductility (a low ductile-brittle transition temperature) is guaranteed in contrast to pure tungsten. As measures to improve the strength, solid-solution as well as precipitation hardening of the binder have been applied. It was the intention of this investigation to explore the possibilities for a strengthening method which has so far not been taken into consideration, namely exploiting the possible capacity of the material for dynamic strain aging (DSA). Such strengthening was proved to be technically feasible in steels. DSA and the accompanying effect of serrated flow (the Portevin-Le Chatelier effect) has never been reported to occur in tungsten heavy alloys. One recent observation of another aspect of DSA, i.e., of a negative strain-rate sensitivity, around 200 C is ambiguous for two reasons: (a) this low temperature cannot indicate an interstitial effect in tungsten--only perhaps in a b.c.c. iron-alloy binder, but not in a binder phase of common composition with a f.c.c. lattice; and (b) the fracture elongation showed a maximum at this temperature which is contrary to the idea of DSA. However, it is still to be expected that substitutional DSA may occur at higher temperatures due to tungsten which should be present in the binder phase after having been dissolved during liquid-phase sintering.

Kumar, S.; Pink, E. [Oesterreichische Akademie der Wissenschaften, Leoben (Austria). Erich-Schmid-Inst. fuer Festkoerperphysik] [Oesterreichische Akademie der Wissenschaften, Leoben (Austria). Erich-Schmid-Inst. fuer Festkoerperphysik; Grill, R. [Technologie-Zentrum, Reutte (Austria). Plansee Aktiengesellschaft] [Technologie-Zentrum, Reutte (Austria). Plansee Aktiengesellschaft

1996-11-01

458

The use of a biodegradable chelator for enhanced phytoextraction of heavy metals by Festuca arundinacea from municipal solid waste compost and associated heavy metal leaching.  

PubMed

In a column experiment with horizontal permeable barriers, the effects of a biodegradable chelator-nitrilotriacetic acid (NTA) on the uptake of heavy metals from municipal solid waste (MSW) compost by Festuca arundinacea and metal leaching were investigated. The use of NTA was effective in increasing Cu, Pb, and Zn uptakes in shoots of two crops of F. arundinacea. In columns with barriers and treated with 20 mmol NTA per kg MSW compost, metal uptakes by the first and second crop of F. arundinacea were, respectively, 3.8 and 4.0 times for Pb, and 1.8 and 1.7 times for Zn greater with the added NTA than without it. Though NTA application mobilized metals, it caused only slight leaching of metals from MSW compost. Permeable barriers positioned between compost and soil effectively reduced metal leaching. NTA-assisted phytoextraction by turfgrass with permeable barriers to cleanup heavy metal contaminated MSW compost should be environmentally safe. PMID:23247507

Zhao, Shulan; Jia, Lina; Duo, Lian

2013-02-01

459

Heavy Metal Pollution in Urban Soils of Sopron  

NASA Astrophysics Data System (ADS)

Keywords: anthropogenic effects, land use types, heavy metal content, polluted urban soils, GIS methods Our aim was to identify the main feedback effects between the town and its environment. In the course of our investigation we have analysed the heavy metal contents of urban soil in Sopron town in Hungary. We collected 208 samples on 104 points from 0 to 10 and from 10 to 20 cm depth in a standard network and also at industrial territories. We have been represented our results in a GIS system. We analysed the soils with Lakanen-Erviö method and we measured 24 elements but we have been focused on Co, Cd, Cu, Pb and Zn. Using the data we observed the relationship between these elements in both layers. In the downtown the acidity of soils were alkaline by the greatest number of point, therefore the pollution of these soils is not leach in deeper layers yet. The lead was very high (> 100 mg Pb/kg) in both layers on the whole area of the town. Urban soils with high copper content (among 611 mg and 1221 mg Cu/kg) have been collected from garden and viticulture areas by us. Cadmium contents were the highest (6.14 mg Cd/kg) in traffic zones, where these values could be more than 3 mg Cd/kg according to the literature. The cobalt and zinc results were under the limits. According to our measurements we founded the highest average values in the soils of parks. This could be contamination of the lead from traffic, which bind in the soil of urban green spaces. Now we could continue our examinations with the investigations of these polluted green areas, which can effect to human health.

Horváth, Adrienn; Bidló, András

2014-05-01

460

Dendrochronology and heavy metal depsosition in tree rings of baldcypress  

SciTech Connect

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 refineries and other sources contaminated the bayou commencing in the early 1900s. The Pb and Zn content of 50 trees along Bayou Trepagnier, analyzed in the growth rings of tree cores using x-ray fluorescent spectrometry, produced an historical record of pollution. Highlevels of contamination of Pb, as well as Zn, could be correlated with establishment of petroleum refineries (1916) and dredging (1930-1950) of the area, which created spoil banks containing high levels (ca. 300-1600 mg/kg [ppm] Pb) of heavy metals. Concentrations of Pb, per tree, ranged form 0.6 to 14 mg/kg (ppm). Trees in the upper protion of the bayou (near the refiney) contained an average of 4.5 mg/kg (ppm) Pb; trees in the lower portion averaged 2.2 mg/kg (ppm). Concentrations of Zn per tree ranged from 1.7 to 14.8 mg/kg (ppm), but in contrast with Pb did not correlate with distance from pollution sources; trees averaged 5.5 and 5.4 mg/kg (ppm) Zn in the upper and lower portions, respectively, of Bayou Trepagnier. Levels of Pb and Zn in a control ecosystem, Stinking Bayou, were 1.0 and 5.2 mg/kg (ppm), respectively. 39 refs., 7 figs., 2 tabs.

Latimer, S.D.; Ellgaard, E.G.; Kumar, S.D. [Tulane Univ., New Orleans, LA (United States)] [and others

1996-11-01

461

Effects of different cleaning treatments on heavy metal removal of Panax notoginseng (Burk) F. H. Chen.  

PubMed

The quality and safety of Panax notoginseng products has become a focus of concern in recent years. Contamination with heavy metals is one of the important factors as to P. notoginseng safety. Cleaning treatments can remove dust, soil, impurities or even heavy metals and pesticide residues on agricultural products. But effects of cleaning treatments on the heavy metal content of P. notoginseng roots have still not been studied. In order to elucidate this issue, the effects of five different cleaning treatments (CK, no treatment; T1, warm water (50°C) washing; T2, tap water (10°C) washing; T3, drying followed by polishing; and T4, drying followed by tap water (10°C) washing) on P. notoginseng roots' heavy metal (Cu, Pb, Cd, As and Hg) contents were studied. The results showed that heavy metal (all five) content in the three parts all followed the order of hair root > rhizome > root tuber under the same treatment. Heavy metal removals were in the order of Hg > As > Pb > Cu > Cd. Removal efficiencies of the four treatments were in the order of T2 > T1 > T3 > T4. Treatments (T1-T4) could decrease the contents of heavy metal in P. notoginseng root significantly. Compared with the requirements of WM/T2-2004, P. notoginseng roots' heavy metal contents of Cu, Pb, As and Hg were safe under treatments T1 and T2. In conclusion, the cleaning process after production was necessary and could reduce the content of heavy metals significantly. Fresh P. notoginseng root washed with warm water (T2) was the most efficient treatment to remove heavy metal and should be applied in production. PMID:25315359

Dahui, Liu; Na, Xu; Li, Wang; Xiuming, Cui; Lanping, Guo; Zhihui, Zhang; Jiajin, Wang; Ye, Yang

2014-12-01

462

Immobilisation of heavy metal in cement-based solidification/stabilisation: a review.  

PubMed

Heavy metal-bearing waste usually needs solidification/stabilization (s/s) prior to landfill to lower the leaching rate. Cement is the most adaptable binder currently available for the immobilisation of heavy metals. The selection of cements and operating parameters depends upon an understanding of chemistry of the system. This paper discusses interactions of heavy metals and cement phases in the solidification/stabilisation process. It provides a clarification of heavy metal effects on cement hydration. According to the decomposition rate of minerals, heavy metals accelerate the hydration of tricalcium silicate (C3S) and Portland cement, although they retard the precipitation of portlandite due to the reduction of pH resulted from hydrolyses of heavy metal ions. The chemical mechanism relevant to the accelerating effect of heavy metals is considered to be H+ attacks on cement phases and the precipitation of calcium heavy metal double hydroxides, which consumes calcium ions and then promotes the decomposition of C3S. In this work, molecular models of calcium silicate hydrate gel are presented based on the examination of 29Si solid-state magic angle spinning/nuclear magnetic resonance (MAS/NMR). This paper also reviews immobilisation mechanisms of heavy metals in hydrated cement matrices, focusing on the sorption, precipitation and chemical incorporation of cement hydration products. It is concluded that further research on the phase development during cement hydration in the presence of heavy metals and thermodynamic modelling is needed to improve effectiveness of cement-based s/s and extend this waste management technique. PMID:18367391

Chen, Q Y; Tyrer, M; Hills, C D; Yang, X M; Carey, P

2009-01-01

463

Multivariate correlations of geochemical binding phases of heavy metals in contaminated river sediment.  

PubMed

Distributions of geochemical binding phases of seven heavy metals (Cr, Cu, Co, Zn, Ni, Pb, and Cd) in sediment cores taken from six heavily polluted sites of the Ell-Ren River in Southern Taiwan were studied. Sequential extraction procedures (SEP) were used to determine the variations of heavy metal binding phases (exchangeable, bound to carbonates, bound to manganese-oxides, bound to iron-oxides, and bound to organic matter) in different sediment depths. Multivariate analyses were used to explore the correlations among these geochemical binding phases of heavy metals. Results showed that the total amounts of various binding phases of heavy metals significantly varied with sediment depth, but their binding behaviors in various phases did not significantly change with depth. The organic matter content in the sediments increased with increasing Fe-oxide content. In addition, the binding affinities of carbonates with Zn, Pb, and Ni were higher than the affinities of carbonates with the other heavy metals. The binding affinity of Fe-oxides with Cr was higher than the affinities of Fe-oxides with the other heavy metals. Both correlation matrixes and principal component analyses demonstrated that distributions of Cu, Zn, Ni, and Cd had significant correlations with each other in both different depth horizons and various geochemical binding phases. The results indicate that these heavy metals might be discharged from the same pollution sources in the past, and also showed stable geochemical binding behaviors with the high silt sediment. However, Co had a poor correlation with the other six heavy metals in various binding phases, except with organic matter. Binding behaviors of Pb in the phases of bound to carbonates and exchangeable were different from the other six heavy metals. Cu was inversly correlated with the other six heavy metals in its binding behavior with reducible phases (Fe-/Mn-oxides). PMID:11381779

Yu, K C; Tsai, L J; Chen, S H; Chang, D J; Ho, S T

2001-01-01

464

Immobilisation of heavy metal in cement-based solidification/stabilisation: A review  

SciTech Connect

Heavy metal-bearing waste usually needs solidification/stabilization (s/s) prior to landfill to lower the leaching rate. Cement is the most adaptable binder currently available for the immobilisation of heavy metals. The selection of cements and operating parameters depends upon an understanding of chemistry of the system. This paper discusses interactions of heavy metals and cement phases in the solidification/stabilisation process. It provides a clarification of heavy metal effects on cement hydration. According to the decomposition rate of minerals, heavy metals accelerate the hydration of tricalcium silicate (C{sub 3}S) and Portland cement, although they retard the precipitation of portlandite due to the reduction of pH resulted from hydrolyses of heavy metal ions. The chemical mechanism relevant to the accelerating effect of heavy metals is considered to be H{sup +} attacks on cement phases and the precipitation of calcium heavy metal double hydroxides, which consumes calcium ions and then promotes the decomposition of C{sub 3}S. In this work, molecular models of calcium silicate hydrate gel are presented based on the examination of {sup 29}Si solid-state magic angle spinning/nuclear magnetic resonance (MAS/NMR). This paper also reviews immobilisation mechanisms of heavy metals in hydrated cement matrices, focusing on the sorption, precipitation and chemical incorporation of cement hydration products. It is concluded that further research on the phase development during cement hydration in the presence of heavy metals and thermodynamic modelling is needed to improve effectiveness of cement-based s/s and extend this waste management technique.

Chen, Q.Y. [School of Environmental Science and Engineering, Donghua University, Shanghai 200051 (China)], E-mail: qychen@dhu.edu.cn; Tyrer, M. [Department of Materials, Imperial College of Science, Technology and Medicine, London SW7 4AZ (United Kingdom); Hills, C.D. [Centre for Contaminated Land Remediation, Medway School of Science, University of Greenwich, Chatham Maritime, Kent ME4 4TB (United Kingdom); Yang, X.M. [School of Environmental Science and Engineering, Donghua University, Shanghai 200051 (China); Carey, P. [Centre for Contaminated Land Remediation, Medway School of Science, University of Greenwich, Chatham Maritime, Kent ME4 4TB (United Kingdom)

2009-01-15

465

HEAVY METAL, ORGANOCHLORINE PESTICIDE AND POLYCHLORINATED BIPHENYL CONTAMINATION IN ARCTIC GROUND SQUIRRELS (SPERMOPHILUS PARRYI) IN NORTHERN ALASKA  

EPA Science Inventory

Heavy metal and organochlorine (OC)concentrations, including organochlorine pesticides and polychlorinated biphenyl congeners (PCBs), were determined in arctic ground squirrels (Spermophilus parryi) from three sites in the Brooks Range of northern Alaska in 1991-93. Heavy metals ...

466

The use of Fontinalis antipyretica L. ex Hedw. as a bioindicator for heavy metals. 2. Heavy metal accumulation and physiological reaction of Fontinalis antipyretica L. ex Hedw. in active biomonitoring in the River Elbe  

Microsoft Academic Search

The aquatic moss Fontinalis antipyretica was studied for its ability to accumulate heavy metals. In an exposure test in the River Elbe it was possible to detect an accumulation of heavy metals at the measuring sites of the water monitoring network of the state of Saxonu-Anhalt (Germany). A correlation between these results and the degrees of heavy-metal pollution in the

I. Bruns; K. Friese; B. Markert; G.-J. Krauss

1997-01-01

467

Impact of Heavy metal toxicity and Constructed wetland system as a tool in remediation.  

PubMed

Abstract The objective of this review is to throw light upon the global concern of heavy metal contaminated sites and its remediation through an ecofriendly approach. Accumulated heavy metals in soil and water bodies gain entry through the food chain and pose serious threat to all forms of life. This has engendered interest in phytoremediation technique where hyperaccumulators are used. Constructed wetland has a pivotal role and is cost effective technique in the remediation of heavy metals. Metal availability and mobility is influenced by the addition of chelating agents which enhances the availability of metal uptake. It helps in identifying the critical knowledge gaps and areas to enhance research in future to develop strategies like genetic engineered hyper accumulators to attain an environment devoid of heavy metal contamination. PMID:25454352

Usharani, B; Vasudevan, N

2014-12-01

468

Heavy metal distribution of natural and reclaimed tidal riparian wetlands in south estuary, China.  

PubMed

We evaluated the distribution and accumulation of Cd, Cr, Cu, Ni, Pb and Zn in two plant species (Scirpus tripueter Linn. and Cyperus malaccensis Lam.), in water and soils sampled from the reclaimed tidal riparian wetlands (RTRWs) and the natural riparian wetlands (NRWs) in the Pearl River Estuary (PRE). The results showed that the concentrations of studied heavy metals in soils exceeded the eco-toxic threshold recommended by US EPA. The concentrations of Cd, Cr and Zn in plants may lead to toxic effects. The heavy metal concentrations were high in water and low in soils of RTRWs compared with that in the NRWs. The accumulation of heavy metals in the roots of plants was higher in NRWs than those in RTRWs while the opposite result was found for heavy metal accumulation in shoots. Based on the bioaccumulation and translocation factors, the plants in NRWs had a higher capacity to accumulate heavy metals while higher abilities to transport heavy metals from roots to shoots were observed in RTRWs. Heavy metal contaminations in RTRWs were dominated by anthropogenic sources from both side uplands and river water, whereas in NRWs, the metal accumulations were simultaneously affected by anthropogenic and natural factors PMID:22432322

Zhang, Honggang; Cui, Baoshan; Zhang, Kejiang

2011-01-01

469

Microbial links between sulfate reduction and metal retention in uranium- and heavy metal-contaminated soil.  

PubMed

Sulfate-reducing bacteria (SRB) can affect metal mobility either directly by reductive transformation of metal ions, e.g., uranium, into their insoluble forms or indirectly by formation of metal sulfides. This study evaluated in situ and biostimulated activity of SRB in groundwater-influenced soils from a creek bank contaminated with heavy metals and radionuclides within the former uranium mining district of Ronneburg, Germany. In situ activity of SRB, measured by the (35)SO(4)(2-) radiotracer method, was restricted to reduced soil horizons with rates of < or =142 +/- 20 nmol cm(-3) day(-1). Concentrations of heavy metals were enriched in the solid phase of the reduced horizons, whereas pore water concentrations were low. X-ray absorption near-edge structure (XANES) measurements demonstrated that approximately 80% of uranium was present as reduced uranium but appeared to occur as a sorbed complex. Soil-based dsrAB clone libraries were dominated by sequences affiliated with members of the Desulfobacterales but also the Desulfovibrionales, Syntrophobacteraceae, and Clostridiales. [(13)C]acetate- and [(13)C]lactate-biostimulated soil microcosms were dominated by sulfate and Fe(III) reduction. These processes were associated with enrichment of SRB and Geobacteraceae; enriched SRB were closely related to organisms detected in soils by using the dsrAB marker. Concentrations of soluble nickel, cobalt, and occasionally zinc declined < or =100% during anoxic soil incubations. In contrast to results in other studies, soluble uranium increased in carbon-amended treatments, reaching < or =1,407 nM in solution. Our results suggest that (i) ongoing sulfate reduction in contaminated soil resulted in in situ metal attenuation and (ii) the fate of uranium mobility is not predictable and may lead to downstream contamination of adjacent ecosystems. PMID:20363796

Sitte, Jana; Akob, Denise M; Kaufmann, Christian; Finster, Kai; Banerjee, Dipanjan; Burkhardt, Eva-Maria; Kostka, Joel E; Scheinost, Andreas C; Büchel, Georg; Küsel, Kirsten

2010-05-01

470

Heavy metals in three lakes in West Poland.  

PubMed

Concentrations of heavy metals (Ni, Cr, Co, Zn, Mn, Pb, Cd, Cu, Hg, Fe) as well as macronutrients (P, Ca, Mg) were measured in water, bottom sediments, and plants of three lakes in West Poland (southwest of Poznan). The plants collected were Nymphaea alba, Nuphar luteum, Ceratophyllum demersum, Phragmites communis, Typha latifolia, and Schoenoplectus lacustris. These plants contained elevated levels of Co, Zn, Pb, Cd, Cr, and Hg. Analyses of water and bottom sediments indicated that the lakes were polluted with Zn, Cd, Cu, and Pb and partly with Ni and Hg. Strong positive correlations were found between concentrations of Cd in water and in plants, between concentrations of Cd in bottom sediments and in plants, between concentrations of Cr in water and in plants, between concentrations of Cr in bottom sediments and in plants, and between concentrations of Fe in water and in plants, indicating the potential of plants for pollution monitoring for these metals. A negative correlation was found between biomass production and Pb and Mn content in water and Pb and Mn content in bottom sediments. Cr and Cd accumulated in plants at a higher rate from bottom sediments than from water. The accumulation rate of Fe in plant tissues was higher with an increase in Fe in water than with an increase in Fe in bottom sediments. PMID:10330316

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

1999-05-01

471

Spectroscopic study of heavy metals sorption on clinoptilolite  

NASA Astrophysics Data System (ADS)

Sorption of heavy metal cations (Pb(II), Cr(III), Cd(II), Ni(II)) from aqueous solutions on natural Na-clinoptilolite was studied using atomic absorption spectrometry (AAS) and FT-IR spectroscopy. It was found that the sorption capacity of clinoptilolite decreases in the following order: Pb(II) (22,600 mg/kg), Cr(III) (21,200 mg/kg), Cd(II) (10,400 mg/kg) and Ni(II) (6,200 mg/kg). In the FT-IR spectra of the samples, in the region of pseudolattice vibrations (500 800 cm-